7031 lines
276 KiB
Plaintext
7031 lines
276 KiB
Plaintext
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Bundle of old SSLeay documentation files [OBSOLETE!]
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*** WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! ***
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OBSOLETE means that nothing in this document should be trusted. This
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document is provided mostly for historical purposes (it wasn't even up
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to date at the time SSLeay 0.8.1 was released) and as inspiration. If
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you copy some snippet of code from this document, please _check_ that
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it really is correct from all points of view. For example, you can
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check with the other documents in this directory tree, or by comparing
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with relevant parts of the include files.
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People have done the mistake of trusting what's written here. Please
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don't do that.
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*** WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! ***
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==== readme ========================================================
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This is the old 0.6.6 docuementation. Most of the cipher stuff is still
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relevent but I'm working (very slowly) on new docuemtation.
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The current version can be found online at
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http://www.cryptsoft.com/ssleay/doc
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==== API.doc ========================================================
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SSL - SSLv2/v3/v23 etc.
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BIO - methods and how they plug together
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MEM - memory allocation callback
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CRYPTO - locking for threads
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EVP - Ciphers/Digests/signatures
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RSA - methods
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X509 - certificate retrieval
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X509 - validation
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X509 - X509v3 extensions
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Objects - adding object identifiers
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ASN.1 - parsing
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PEM - parsing
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==== ssl/readme =====================================================
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22 Jun 1996
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This file belongs in ../apps, but I'll leave it here because it deals
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with SSL :-) It is rather dated but it gives you an idea of how
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things work.
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===
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17 Jul 1995
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I have been changing things quite a bit and have not fully updated
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this file, so take what you read with a grain of salt
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eric
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===
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The s_client and s_server programs can be used to test SSL capable
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IP/port addresses and the verification of the X509 certificates in use
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by these services. I strongly advise having a look at the code to get
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an idea of how to use the authentication under SSLeay. Any feedback
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on changes and improvements would be greatly accepted.
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This file will probably be gibberish unless you have read
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rfc1421, rfc1422, rfc1423 and rfc1424 which describe PEM
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authentication.
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A Brief outline (and examples) how to use them to do so.
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NOTE:
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The environment variable SSL_CIPER is used to specify the prefered
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cipher to use, play around with setting it's value to combinations of
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RC4-MD5, EXP-RC4-MD5, CBC-DES-MD5, CBC3-DES-MD5, CFB-DES-NULL
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in a : separated list.
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This directory contains 3 X509 certificates which can be used by these programs.
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client.pem: a file containing a certificate and private key to be used
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by s_client.
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server.pem :a file containing a certificate and private key to be used
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by s_server.
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eay1024.pem:the certificate used to sign client.pem and server.pem.
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This would be your CA's certificate. There is also a link
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from the file a8556381.0 to eay1024.PEM. The value a8556381
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is returned by 'x509 -hash -noout <eay1024.pem' and is the
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value used by X509 verification routines to 'find' this
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certificte when search a directory for it.
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[the above is not true any more, the CA cert is
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../certs/testca.pem which is signed by ../certs/mincomca.pem]
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When testing the s_server, you may get
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bind: Address already in use
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errors. These indicate the port is still being held by the unix
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kernel and you are going to have to wait for it to let go of it. If
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this is the case, remember to use the port commands on the s_server and
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s_client to talk on an alternative port.
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=====
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s_client.
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This program can be used to connect to any IP/hostname:port that is
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talking SSL. Once connected, it will attempt to authenticate the
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certificate it was passed and if everything works as expected, a 2
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directional channel will be open. Any text typed will be sent to the
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other end. type Q<cr> to exit. Flags are as follows.
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-host arg : Arg is the host or IP address to connect to.
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-port arg : Arg is the port to connect to (https is 443).
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-verify arg : Turn on authentication of the server certificate.
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: Arg specifies the 'depth', this will covered below.
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-cert arg : The optional certificate to use. This certificate
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: will be returned to the server if the server
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: requests it for client authentication.
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-key arg : The private key that matches the certificate
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: specified by the -cert option. If this is not
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: specified (but -cert is), the -cert file will be
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: searched for the Private key. Both files are
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: assumed to be in PEM format.
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-CApath arg : When to look for certificates when 'verifying' the
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: certificate from the server.
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-CAfile arg : A file containing certificates to be used for
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: 'verifying' the server certificate.
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-reconnect : Once a connection has been made, drop it and
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: reconnect with same session-id. This is for testing :-).
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The '-verify n' parameter specifies not only to verify the servers
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certificate but to also only take notice of 'n' levels. The best way
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to explain is to show via examples.
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Given
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s_server -cert server.PEM is running.
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s_client
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CONNECTED
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depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo server
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issuer= /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA
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verify error:num=1:unable to get issuer certificate
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verify return:1
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CIPHER is CBC-DES-MD5
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What has happened is that the 'SSLeay demo server' certificate's
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issuer ('CA') could not be found but because verify is not on, we
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don't care and the connection has been made anyway. It is now 'up'
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using CBC-DES-MD5 mode. This is an unauthenticate secure channel.
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You may not be talking to the right person but the data going to them
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is encrypted.
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s_client -verify 0
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CONNECTED
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depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo server
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issuer= /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA
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verify error:num=1:unable to get issuer certificate
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verify return:1
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CIPHER is CBC-DES-MD5
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We are 'verifying' but only to depth 0, so since the 'SSLeay demo server'
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certificate passed the date and checksum, we are happy to proceed.
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s_client -verify 1
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CONNECTED
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depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo server
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issuer= /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA
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verify error:num=1:unable to get issuer certificate
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verify return:0
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ERROR
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verify error:unable to get issuer certificate
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In this case we failed to make the connection because we could not
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authenticate the certificate because we could not find the
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'CA' certificate.
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s_client -verify 1 -CAfile eay1024.PEM
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CONNECTED
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depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo server
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verify return:1
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depth=1 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA
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verify return:1
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CIPHER is CBC-DES-MD5
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We loaded the certificates from the file eay1024.PEM. Everything
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checked out and so we made the connection.
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s_client -verify 1 -CApath .
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CONNECTED
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depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo server
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verify return:1
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depth=1 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA
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verify return:1
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CIPHER is CBC-DES-MD5
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We looked in out local directory for issuer certificates and 'found'
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a8556381.0 and so everything is ok.
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It is worth noting that 'CA' is a self certified certificate. If you
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are passed one of these, it will fail to 'verify' at depth 0 because
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we need to lookup the certifier of a certificate from some information
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that we trust and keep locally.
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SSL_CIPHER=CBC3-DES-MD5:RC4-MD5
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export SSL_CIPHER
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s_client -verify 10 -CApath . -reconnect
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CONNECTED
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depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo server
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verify return:1
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depth=1 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA
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verify return:1
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drop the connection and reconnect with the same session id
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CIPHER is CBC3-DES-MD5
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This has done a full connection and then re-estabished it with the
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same session id but a new socket. No RSA stuff occures on the second
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connection. Note that we said we would prefer to use CBC3-DES-MD5
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encryption and so, since the server supports it, we are.
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=====
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s_server
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This program accepts SSL connections on a specified port
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Once connected, it will estabish an SSL connection and optionaly
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attempt to authenticate the client. A 2 directional channel will be
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open. Any text typed will be sent to the other end. Type Q<cr> to exit.
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Flags are as follows.
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-port arg : Arg is the port to listen on.
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-verify arg : Turn on authentication of the client if they have a
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: certificate. Arg specifies the 'depth'.
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-Verify arg : Turn on authentication of the client. If they don't
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: have a valid certificate, drop the connection.
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-cert arg : The certificate to use. This certificate
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: will be passed to the client. If it is not
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: specified, it will default to server.PEM
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-key arg : The private key that matches the certificate
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: specified by the -cert option. If this is not
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: specified (but -cert is), the -cert file will be
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: searched for the Private key. Both files are
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: assumed to be in PEM format. Default is server.PEM
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-CApath arg : When to look for certificates when 'verifying' the
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: certificate from the client.
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-CAfile arg : A file containing certificates to be used for
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: 'verifying' the client certificate.
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For the following 'demo' I will specify the s_server command and
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the s_client command and then list the output from the s_server.
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s_server
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s_client
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CONNECTED
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CIPHER is CBC-DES-MD5
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Everything up and running
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s_server -verify 0
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s_client
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CONNECTED
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CIPHER is CBC-DES-MD5
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Ok since no certificate was returned and we don't care.
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s_server -verify 0
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./s_client -cert client.PEM
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CONNECTED
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depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo client
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issuer= /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA
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verify error:num=1:unable to get issuer certificate
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verify return:1
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CIPHER is CBC-DES-MD5
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Ok since we were only verifying to level 0
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s_server -verify 4
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s_client -cert client.PEM
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CONNECTED
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depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo client
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issuer= /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA
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verify error:num=1:unable to get issuer certificate
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verify return:0
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ERROR
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verify error:unable to get issuer certificate
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Bad because we could not authenticate the returned certificate.
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s_server -verify 4 -CApath .
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s_client -cert client.PEM
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CONNECTED
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depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo client
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verify return:1
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depth=1 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA
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verify return:1
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CIPHER is CBC-DES-MD5
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Ok because we could authenticate the returned certificate :-).
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s_server -Verify 0 -CApath .
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s_client
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CONNECTED
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ERROR
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SSL error:function is:REQUEST_CERTIFICATE
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:error is :client end did not return a certificate
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Error because no certificate returned.
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s_server -Verify 4 -CApath .
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s_client -cert client.PEM
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CONNECTED
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depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo client
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verify return:1
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depth=1 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA
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verify return:1
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CIPHER is CBC-DES-MD5
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Full authentication of the client.
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So in summary to do full authentication of both ends
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s_server -Verify 9 -CApath .
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s_client -cert client.PEM -CApath . -verify 9
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From the server side
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CONNECTED
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depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo client
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verify return:1
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depth=1 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA
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verify return:1
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CIPHER is CBC-DES-MD5
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From the client side
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CONNECTED
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depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo server
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verify return:1
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depth=1 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA
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verify return:1
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CIPHER is CBC-DES-MD5
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For general probing of the 'internet https' servers for the
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distribution area, run
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s_client -host www.netscape.com -port 443 -verify 4 -CApath ../rsa/hash
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Then enter
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GET /
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and you should be talking to the https server on that host.
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www.rsa.com was refusing to respond to connections on 443 when I was
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testing.
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have fun :-).
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eric
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==== a_verify.doc ========================================================
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From eay@mincom.com Fri Oct 4 18:29:06 1996
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Received: by orb.mincom.oz.au id AA29080
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(5.65c/IDA-1.4.4 for eay); Fri, 4 Oct 1996 08:29:07 +1000
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Date: Fri, 4 Oct 1996 08:29:06 +1000 (EST)
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From: Eric Young <eay@mincom.oz.au>
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X-Sender: eay@orb
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To: wplatzer <wplatzer@iaik.tu-graz.ac.at>
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Cc: Eric Young <eay@mincom.oz.au>, SSL Mailing List <ssl-users@mincom.com>
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Subject: Re: Netscape's Public Key
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In-Reply-To: <19961003134837.NTM0049@iaik.tu-graz.ac.at>
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Message-Id: <Pine.SOL.3.91.961004081346.8018K-100000@orb>
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Mime-Version: 1.0
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Content-Type: TEXT/PLAIN; charset=US-ASCII
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Status: RO
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X-Status:
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On Thu, 3 Oct 1996, wplatzer wrote:
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> I get Public Key from Netscape (Gold 3.0b4), but cannot do anything
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> with it... It looks like (asn1parse):
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>
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> 0:d=0 hl=3 l=180 cons: SEQUENCE
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> 3:d=1 hl=2 l= 96 cons: SEQUENCE
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> 5:d=2 hl=2 l= 92 cons: SEQUENCE
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> 7:d=3 hl=2 l= 13 cons: SEQUENCE
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> 9:d=4 hl=2 l= 9 prim: OBJECT :rsaEncryption
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> 20:d=4 hl=2 l= 0 prim: NULL
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> 22:d=3 hl=2 l= 75 prim: BIT STRING
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> 99:d=2 hl=2 l= 0 prim: IA5STRING :
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> 101:d=1 hl=2 l= 13 cons: SEQUENCE
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> 103:d=2 hl=2 l= 9 prim: OBJECT :md5withRSAEncryption
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> 114:d=2 hl=2 l= 0 prim: NULL
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> 116:d=1 hl=2 l= 65 prim: BIT STRING
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>
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> The first BIT STRING is the public key and the second BIT STRING is
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> the signature.
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> But a public key consists of the public exponent and the modulus. Are
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> both numbers in the first BIT STRING?
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> Is there a document simply describing this coding stuff (checking
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> signature, get the public key, etc.)?
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Minimal in SSLeay. If you want to see what the modulus and exponent are,
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try asn1parse -offset 25 -length 75 <key.pem
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asn1parse will currently stuff up on the 'length 75' part (fixed in next
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release) but it will print the stuff. If you are after more
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documentation on ASN.1, have a look at www.rsa.com and get their PKCS
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documents, most of my initial work on SSLeay was done using them.
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As for SSLeay,
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util/crypto.num and util/ssl.num are lists of all exported functions in
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the library (but not macros :-(.
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The ones for extracting public keys from certificates and certificate
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requests are EVP_PKEY * X509_REQ_extract_key(X509_REQ *req);
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EVP_PKEY * X509_extract_key(X509 *x509);
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To verify a signature on a signed ASN.1 object
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int X509_verify(X509 *a,EVP_PKEY *key);
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int X509_REQ_verify(X509_REQ *a,EVP_PKEY *key);
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int X509_CRL_verify(X509_CRL *a,EVP_PKEY *key);
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int NETSCAPE_SPKI_verify(NETSCAPE_SPKI *a,EVP_PKEY *key);
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I should mention that EVP_PKEY can be used to hold a public or a private key,
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since for things like RSA and DSS, a public key is just a subset of what
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is stored for the private key.
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To sign any of the above structures
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int X509_sign(X509 *a,EVP_PKEY *key,EVP_MD *md);
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int X509_REQ_sign(X509_REQ *a,EVP_PKEY *key,EVP_MD *md);
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int X509_CRL_sign(X509_CRL *a,EVP_PKEY *key,EVP_MD *md);
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int NETSCAPE_SPKI_sign(NETSCAPE_SPKI *a,EVP_PKEY *key,EVP_MD *md);
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where md is the message digest to sign with.
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There are all defined in x509.h and all the _sign and _verify functions are
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actually macros to the ASN1_sign() and ASN1_verify() functions.
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These functions will put the correct algorithm identifiers in the correct
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places in the structures.
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eric
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--
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Eric Young | BOOL is tri-state according to Bill Gates.
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AARNet: eay@mincom.oz.au | RTFM Win32 GetMessage().
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==== x509 =======================================================
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X509_verify()
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X509_sign()
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X509_get_version()
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X509_get_serialNumber()
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X509_get_issuer()
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X509_get_subject()
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X509_get_notBefore()
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X509_get_notAfter()
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X509_get_pubkey()
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X509_set_version()
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X509_set_serialNumber()
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X509_set_issuer()
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X509_set_subject()
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X509_set_notBefore()
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X509_set_notAfter()
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X509_set_pubkey()
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X509_get_extensions()
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X509_set_extensions()
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X509_EXTENSIONS_clear()
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X509_EXTENSIONS_retrieve()
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X509_EXTENSIONS_add()
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X509_EXTENSIONS_delete()
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==== x509 attribute ================================================
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PKCS7
|
|
STACK of X509_ATTRIBUTES
|
|
ASN1_OBJECT
|
|
STACK of ASN1_TYPE
|
|
|
|
So it is
|
|
|
|
p7.xa[].obj
|
|
p7.xa[].data[]
|
|
|
|
get_obj_by_nid(STACK , nid)
|
|
get_num_by_nid(STACK , nid)
|
|
get_data_by_nid(STACK , nid, index)
|
|
|
|
X509_ATTRIBUTE *X509_ATTRIBUTE_new(void );
|
|
void X509_ATTRIBUTE_free(X509_ATTRIBUTE *a);
|
|
|
|
X509_ATTRIBUTE *X509_ATTRIBUTE_create_by_NID(X509_ATTRIBUTE **ex,
|
|
int nid, STACK *value);
|
|
|
|
X509_ATTRIBUTE *X509_ATTRIBUTE_create_by_OBJ(X509_ATTRIBUTE **ex,
|
|
int nid, STACK *value);
|
|
|
|
int X509_ATTRIBUTE_set_object(X509_ATTRIBUTE *ex,ASN1_OBJECT *obj);
|
|
int X509_ATTRIBUTE_add_data(X509_ATTRIBUTE *ex, int index,
|
|
ASN1_TYPE *value);
|
|
|
|
ASN1_OBJECT * X509_ATTRIBUTE_get_object(X509_ATTRIBUTE *ex);
|
|
int X509_ATTRIBUTE_get_num(X509_ATTRIBUTE *ne);
|
|
ASN1_TYPE * X509_ATTRIBUTE_get_data(X509_ATTRIBUTE *ne,int index);
|
|
|
|
ASN1_TYPE * X509_ATTRIBUTE_get_data_by_NID(X509_ATTRIBUTE *ne,
|
|
ASN1_OBJECT *obj);
|
|
|
|
X509_ATTRIBUTE *PKCS7_get_s_att_by_NID(PKCS7 *p7,int nid);
|
|
X509_ATTRIBUTE *PKCS7_get_u_att_by_NID(PKCS7 *p7,int nid);
|
|
|
|
==== x509 v3 ========================================================
|
|
|
|
The 'new' system.
|
|
|
|
The X509_EXTENSION_METHOD includes extensions and attributes and/or names.
|
|
Basically everthing that can be added to an X509 with an OID identifying it.
|
|
|
|
It operates via 2 methods per object id.
|
|
int a2i_XXX(X509 *x,char *str,int len);
|
|
int i2a_XXX(BIO *bp,X509 *x);
|
|
|
|
The a2i_XXX function will add the object with a value converted from the
|
|
string into the X509. Len can be -1 in which case the length is calculated
|
|
via strlen(str). Applications can always use direct knowledge to load and
|
|
unload the relevent objects themselves.
|
|
|
|
i2a_XXX will print to the passed BIO, a text representation of the
|
|
relevet object. Use a memory BIO if you want it printed to a buffer :-).
|
|
|
|
X509_add_by_NID(X509 *x,int nid,char *str,int len);
|
|
X509_add_by_OBJ(X509 *x,ASN1_OBJECT *obj,char *str,int len);
|
|
|
|
X509_print_by_name(BIO *bp,X509 *x);
|
|
X509_print_by_NID(BIO *bp,X509 *x);
|
|
X509_print_by_OBJ(BIO *bp,X509 *x);
|
|
|
|
==== verify ========================================================
|
|
|
|
X509_verify_cert_chain(
|
|
CERT_STORE *cert_store,
|
|
STACK /* X509 */ *certs,
|
|
int *verify_result,
|
|
int (*verify_error_callback)()
|
|
char *argument_to_callback, /* SSL */
|
|
|
|
app_verify_callback(
|
|
char *app_verify_arg, /* from SSL_CTX */
|
|
STACK /* X509 */ *certs,
|
|
int *verify_result,
|
|
int (*verify_error_callback)()
|
|
SSL *s,
|
|
|
|
int X509_verify_cert(
|
|
CERT_STORE *cert_store,
|
|
X509 *x509,
|
|
int *verify_result,
|
|
int (*verify_error_callback)(),
|
|
char *arg,
|
|
|
|
==== apps.doc ========================================================
|
|
|
|
The applications
|
|
|
|
Ok, where to begin....
|
|
In the begining, when SSLeay was small (April 1995), there
|
|
were but few applications, they did happily cohabit in
|
|
the one bin directory. Then over time, they did multiply and grow,
|
|
and they started to look like microsoft software; 500k to print 'hello world'.
|
|
A new approach was needed. They were coalessed into one 'Monolithic'
|
|
application, ssleay. This one program is composed of many programs that
|
|
can all be compiled independantly.
|
|
|
|
ssleay has 3 modes of operation.
|
|
1) If the ssleay binaray has the name of one of its component programs, it
|
|
executes that program and then exits. This can be achieve by using hard or
|
|
symbolic links, or failing that, just renaming the binary.
|
|
2) If the first argument to ssleay is the name of one of the component
|
|
programs, that program runs that program and then exits.
|
|
3) If there are no arguments, ssleay enters a 'command' mode. Each line is
|
|
interpreted as a program name plus arguments. After each 'program' is run,
|
|
ssleay returns to the comand line.
|
|
|
|
dgst - message digests
|
|
enc - encryption and base64 encoding
|
|
|
|
ans1parse - 'pulls' appart ASN.1 encoded objects like certificates.
|
|
|
|
dh - Diffle-Hellman parameter manipulation.
|
|
rsa - RSA manipulations.
|
|
crl - Certificate revokion list manipulations
|
|
x509 - X509 cert fiddles, including signing.
|
|
pkcs7 - pkcs7 manipulation, only DER versions right now.
|
|
|
|
genrsa - generate an RSA private key.
|
|
gendh - Generate a set of Diffle-Hellman parameters.
|
|
req - Generate a PKCS#10 object, a certificate request.
|
|
|
|
s_client - SSL client program
|
|
s_server - SSL server program
|
|
s_time - A SSL protocol timing program
|
|
s_mult - Another SSL server, but it multiplexes
|
|
connections.
|
|
s_filter - under development
|
|
|
|
errstr - Convert SSLeay error numbers to strings.
|
|
ca - Sign certificate requests, and generate
|
|
certificate revokion lists
|
|
crl2pkcs7 - put a crl and certifcates into a pkcs7 object.
|
|
speed - Benchmark the ciphers.
|
|
verify - Check certificates
|
|
hashdir - under development
|
|
|
|
[ there a now a few more options, play with the program to see what they
|
|
are ]
|
|
|
|
==== asn1.doc ========================================================
|
|
|
|
The ASN.1 Routines.
|
|
|
|
ASN.1 is a specification for how to encode structured 'data' in binary form.
|
|
The approach I have take to the manipulation of structures and their encoding
|
|
into ASN.1 is as follows.
|
|
|
|
For each distinct structure there are 4 function of the following form
|
|
TYPE *TYPE_new(void);
|
|
void TYPE_free(TYPE *);
|
|
TYPE *d2i_TYPE(TYPE **a,unsigned char **pp,long length);
|
|
long i2d_TYPE(TYPE *a,unsigned char **pp); /* CHECK RETURN VALUE */
|
|
|
|
where TYPE is the type of the 'object'. The TYPE that have these functions
|
|
can be in one of 2 forms, either the internal C malloc()ed data structure
|
|
or in the DER (a variant of ASN.1 encoding) binary encoding which is just
|
|
an array of unsigned bytes. The 'i2d' functions converts from the internal
|
|
form to the DER form and the 'd2i' functions convert from the DER form to
|
|
the internal form.
|
|
|
|
The 'new' function returns a malloc()ed version of the structure with all
|
|
substructures either created or left as NULL pointers. For 'optional'
|
|
fields, they are normally left as NULL to indicate no value. For variable
|
|
size sub structures (often 'SET OF' or 'SEQUENCE OF' in ASN.1 syntax) the
|
|
STACK data type is used to hold the values. Have a read of stack.doc
|
|
and have a look at the relevant header files to see what I mean. If there
|
|
is an error while malloc()ing the structure, NULL is returned.
|
|
|
|
The 'free' function will free() all the sub components of a particular
|
|
structure. If any of those sub components have been 'removed', replace
|
|
them with NULL pointers, the 'free' functions are tolerant of NULL fields.
|
|
|
|
The 'd2i' function copies a binary representation into a C structure. It
|
|
operates as follows. 'a' is a pointer to a pointer to
|
|
the structure to populate, 'pp' is a pointer to a pointer to where the DER
|
|
byte string is located and 'length' is the length of the '*pp' data.
|
|
If there are no errors, a pointer to the populated structure is returned.
|
|
If there is an error, NULL is returned. Errors can occur because of
|
|
malloc() failures but normally they will be due to syntax errors in the DER
|
|
encoded data being parsed. It is also an error if there was an
|
|
attempt to read more that 'length' bytes from '*p'. If
|
|
everything works correctly, the value in '*p' is updated
|
|
to point at the location just beyond where the DER
|
|
structure was read from. In this way, chained calls to 'd2i' type
|
|
functions can be made, with the pointer into the 'data' array being
|
|
'walked' along the input byte array.
|
|
Depending on the value passed for 'a', different things will be done. If
|
|
'a' is NULL, a new structure will be malloc()ed and returned. If '*a' is
|
|
NULL, a new structure will be malloc()ed and put into '*a' and returned.
|
|
If '*a' is not NULL, the structure in '*a' will be populated, or in the
|
|
case of an error, free()ed and then returned.
|
|
Having these semantics means that a structure
|
|
can call a 'd2i' function to populate a field and if the field is currently
|
|
NULL, the structure will be created.
|
|
|
|
The 'i2d' function type is used to copy a C structure to a byte array.
|
|
The parameter 'a' is the structure to convert and '*p' is where to put it.
|
|
As for the 'd2i' type structure, 'p' is updated to point after the last
|
|
byte written. If p is NULL, no data is written. The function also returns
|
|
the number of bytes written. Where this becomes useful is that if the
|
|
function is called with a NULL 'p' value, the length is returned. This can
|
|
then be used to malloc() an array of bytes and then the same function can
|
|
be recalled passing the malloced array to be written to. e.g.
|
|
|
|
int len;
|
|
unsigned char *bytes,*p;
|
|
len=i2d_X509(x,NULL); /* get the size of the ASN1 encoding of 'x' */
|
|
if ((bytes=(unsigned char *)malloc(len)) == NULL)
|
|
goto err;
|
|
p=bytes;
|
|
i2d_X509(x,&p);
|
|
|
|
Please note that a new variable, 'p' was passed to i2d_X509. After the
|
|
call to i2d_X509 p has been incremented by len bytes.
|
|
|
|
Now the reason for this functional organisation is that it allows nested
|
|
structures to be built up by calling these functions as required. There
|
|
are various macros used to help write the general 'i2d', 'd2i', 'new' and
|
|
'free' functions. They are discussed in another file and would only be
|
|
used by some-one wanting to add new structures to the library. As you
|
|
might be able to guess, the process of writing ASN.1 files can be a bit CPU
|
|
expensive for complex structures. I'm willing to live with this since the
|
|
simpler library code make my life easier and hopefully most programs using
|
|
these routines will have their execution profiles dominated by cipher or
|
|
message digest routines.
|
|
What follows is a list of 'TYPE' values and the corresponding ASN.1
|
|
structure and where it is used.
|
|
|
|
TYPE ASN.1
|
|
ASN1_INTEGER INTEGER
|
|
ASN1_BIT_STRING BIT STRING
|
|
ASN1_OCTET_STRING OCTET STRING
|
|
ASN1_OBJECT OBJECT IDENTIFIER
|
|
ASN1_PRINTABLESTRING PrintableString
|
|
ASN1_T61STRING T61String
|
|
ASN1_IA5STRING IA5String
|
|
ASN1_UTCTIME UTCTime
|
|
ASN1_TYPE Any of the above mentioned types plus SEQUENCE and SET
|
|
|
|
Most of the above mentioned types are actualled stored in the
|
|
ASN1_BIT_STRING type and macros are used to differentiate between them.
|
|
The 3 types used are
|
|
|
|
typedef struct asn1_object_st
|
|
{
|
|
/* both null if a dynamic ASN1_OBJECT, one is
|
|
* defined if a 'static' ASN1_OBJECT */
|
|
char *sn,*ln;
|
|
int nid;
|
|
int length;
|
|
unsigned char *data;
|
|
} ASN1_OBJECT;
|
|
This is used to store ASN1 OBJECTS. Read 'objects.doc' for details ono
|
|
routines to manipulate this structure. 'sn' and 'ln' are used to hold text
|
|
strings that represent the object (short name and long or lower case name).
|
|
These are used by the 'OBJ' library. 'nid' is a number used by the OBJ
|
|
library to uniquely identify objects. The ASN1 routines will populate the
|
|
'length' and 'data' fields which will contain the bit string representing
|
|
the object.
|
|
|
|
typedef struct asn1_bit_string_st
|
|
{
|
|
int length;
|
|
int type;
|
|
unsigned char *data;
|
|
} ASN1_BIT_STRING;
|
|
This structure is used to hold all the other base ASN1 types except for
|
|
ASN1_UTCTIME (which is really just a 'char *'). Length is the number of
|
|
bytes held in data and type is the ASN1 type of the object (there is a list
|
|
in asn1.h).
|
|
|
|
typedef struct asn1_type_st
|
|
{
|
|
int type;
|
|
union {
|
|
char *ptr;
|
|
ASN1_INTEGER * integer;
|
|
ASN1_BIT_STRING * bit_string;
|
|
ASN1_OCTET_STRING * octet_string;
|
|
ASN1_OBJECT * object;
|
|
ASN1_PRINTABLESTRING * printablestring;
|
|
ASN1_T61STRING * t61string;
|
|
ASN1_IA5STRING * ia5string;
|
|
ASN1_UTCTIME * utctime;
|
|
ASN1_BIT_STRING * set;
|
|
ASN1_BIT_STRING * sequence;
|
|
} value;
|
|
} ASN1_TYPE;
|
|
This structure is used in a few places when 'any' type of object can be
|
|
expected.
|
|
|
|
X509 Certificate
|
|
X509_CINF CertificateInfo
|
|
X509_ALGOR AlgorithmIdentifier
|
|
X509_NAME Name
|
|
X509_NAME_ENTRY A single sub component of the name.
|
|
X509_VAL Validity
|
|
X509_PUBKEY SubjectPublicKeyInfo
|
|
The above mentioned types are declared in x509.h. They are all quite
|
|
straight forward except for the X509_NAME/X509_NAME_ENTRY pair.
|
|
A X509_NAME is a STACK (see stack.doc) of X509_NAME_ENTRY's.
|
|
typedef struct X509_name_entry_st
|
|
{
|
|
ASN1_OBJECT *object;
|
|
ASN1_BIT_STRING *value;
|
|
int set;
|
|
int size; /* temp variable */
|
|
} X509_NAME_ENTRY;
|
|
The size is a temporary variable used by i2d_NAME and set is the set number
|
|
for the particular NAME_ENTRY. A X509_NAME is encoded as a sequence of
|
|
sequence of sets. Normally each set contains only a single item.
|
|
Sometimes it contains more. Normally throughout this library there will be
|
|
only one item per set. The set field contains the 'set' that this entry is
|
|
a member of. So if you have just created a X509_NAME structure and
|
|
populated it with X509_NAME_ENTRYs, you should then traverse the X509_NAME
|
|
(which is just a STACK) and set the 'set/' field to incrementing numbers.
|
|
For more details on why this is done, read the ASN.1 spec for Distinguished
|
|
Names.
|
|
|
|
X509_REQ CertificateRequest
|
|
X509_REQ_INFO CertificateRequestInfo
|
|
These are used to hold certificate requests.
|
|
|
|
X509_CRL CertificateRevocationList
|
|
These are used to hold a certificate revocation list
|
|
|
|
RSAPrivateKey PrivateKeyInfo
|
|
RSAPublicKey PublicKeyInfo
|
|
Both these 'function groups' operate on 'RSA' structures (see rsa.doc).
|
|
The difference is that the RSAPublicKey operations only manipulate the m
|
|
and e fields in the RSA structure.
|
|
|
|
DSAPrivateKey DSS private key
|
|
DSAPublicKey DSS public key
|
|
Both these 'function groups' operate on 'DSS' structures (see dsa.doc).
|
|
The difference is that the RSAPublicKey operations only manipulate the
|
|
XXX fields in the DSA structure.
|
|
|
|
DHparams DHParameter
|
|
This is used to hold the p and g value for The Diffie-Hellman operation.
|
|
The function deal with the 'DH' strucure (see dh.doc).
|
|
|
|
Now all of these function types can be used with several other functions to give
|
|
quite useful set of general manipulation routines. Normally one would
|
|
not uses these functions directly but use them via macros.
|
|
|
|
char *ASN1_dup(int (*i2d)(),char *(*d2i)(),char *x);
|
|
'x' is the input structure case to a 'char *', 'i2d' is the 'i2d_TYPE'
|
|
function for the type that 'x' is and d2i is the 'd2i_TYPE' function for the
|
|
type that 'x' is. As is obvious from the parameters, this function
|
|
duplicates the strucutre by transforming it into the DER form and then
|
|
re-loading it into a new strucutre and returning the new strucutre. This
|
|
is obviously a bit cpu intensive but when faced with a complex dynamic
|
|
structure this is the simplest programming approach. There are macros for
|
|
duplicating the major data types but is simple to add extras.
|
|
|
|
char *ASN1_d2i_fp(char *(*new)(),char *(*d2i)(),FILE *fp,unsigned char **x);
|
|
'x' is a pointer to a pointer of the 'desired type'. new and d2i are the
|
|
corresponding 'TYPE_new' and 'd2i_TYPE' functions for the type and 'fp' is
|
|
an open file pointer to read from. This function reads from 'fp' as much
|
|
data as it can and then uses 'd2i' to parse the bytes to load and return
|
|
the parsed strucutre in 'x' (if it was non-NULL) and to actually return the
|
|
strucutre. The behavior of 'x' is as per all the other d2i functions.
|
|
|
|
char *ASN1_d2i_bio(char *(*new)(),char *(*d2i)(),BIO *fp,unsigned char **x);
|
|
The 'BIO' is the new IO type being used in SSLeay (see bio.doc). This
|
|
function is the same as ASN1_d2i_fp() except for the BIO argument.
|
|
ASN1_d2i_fp() actually calls this function.
|
|
|
|
int ASN1_i2d_fp(int (*i2d)(),FILE *out,unsigned char *x);
|
|
'x' is converted to bytes by 'i2d' and then written to 'out'. ASN1_i2d_fp
|
|
and ASN1_d2i_fp are not really symetric since ASN1_i2d_fp will read all
|
|
available data from the file pointer before parsing a single item while
|
|
ASN1_i2d_fp can be used to write a sequence of data objects. To read a
|
|
series of objects from a file I would sugest loading the file into a buffer
|
|
and calling the relevent 'd2i' functions.
|
|
|
|
char *ASN1_d2i_bio(char *(*new)(),char *(*d2i)(),BIO *fp,unsigned char **x);
|
|
This function is the same as ASN1_i2d_fp() except for the BIO argument.
|
|
ASN1_i2d_fp() actually calls this function.
|
|
|
|
char * PEM_ASN1_read(char *(*d2i)(),char *name,FILE *fp,char **x,int (*cb)());
|
|
This function will read the next PEM encoded (base64) object of the same
|
|
type as 'x' (loaded by the d2i function). 'name' is the name that is in
|
|
the '-----BEGIN name-----' that designates the start of that object type.
|
|
If the data is encrypted, 'cb' will be called to prompt for a password. If
|
|
it is NULL a default function will be used to prompt from the password.
|
|
'x' is delt with as per the standard 'd2i' function interface. This
|
|
function can be used to read a series of objects from a file. While any
|
|
data type can be encrypted (see PEM_ASN1_write) only RSA private keys tend
|
|
to be encrypted.
|
|
|
|
char * PEM_ASN1_read_bio(char *(*d2i)(),char *name,BIO *fp,
|
|
char **x,int (*cb)());
|
|
Same as PEM_ASN1_read() except using a BIO. This is called by
|
|
PEM_ASN1_read().
|
|
|
|
int PEM_ASN1_write(int (*i2d)(),char *name,FILE *fp,char *x,EVP_CIPHER *enc,
|
|
unsigned char *kstr,int klen,int (*callback)());
|
|
|
|
int PEM_ASN1_write_bio(int (*i2d)(),char *name,BIO *fp,
|
|
char *x,EVP_CIPHER *enc,unsigned char *kstr,int klen,
|
|
int (*callback)());
|
|
|
|
int ASN1_sign(int (*i2d)(), X509_ALGOR *algor1, X509_ALGOR *algor2,
|
|
ASN1_BIT_STRING *signature, char *data, RSA *rsa, EVP_MD *type);
|
|
int ASN1_verify(int (*i2d)(), X509_ALGOR *algor1,
|
|
ASN1_BIT_STRING *signature,char *data, RSA *rsa);
|
|
|
|
int ASN1_BIT_STRING_cmp(ASN1_BIT_STRING *a, ASN1_BIT_STRING *b);
|
|
ASN1_BIT_STRING *ASN1_BIT_STRING_type_new(int type );
|
|
|
|
int ASN1_UTCTIME_check(ASN1_UTCTIME *a);
|
|
void ASN1_UTCTIME_print(BIO *fp,ASN1_UTCTIME *a);
|
|
ASN1_UTCTIME *ASN1_UTCTIME_dup(ASN1_UTCTIME *a);
|
|
|
|
ASN1_BIT_STRING *d2i_asn1_print_type(ASN1_BIT_STRING **a,unsigned char **pp,
|
|
long length,int type);
|
|
|
|
int i2d_ASN1_SET(STACK *a, unsigned char **pp,
|
|
int (*func)(), int ex_tag, int ex_class);
|
|
STACK * d2i_ASN1_SET(STACK **a, unsigned char **pp, long length,
|
|
char *(*func)(), int ex_tag, int ex_class);
|
|
|
|
int i2a_ASN1_OBJECT(BIO *bp,ASN1_OBJECT *object);
|
|
int i2a_ASN1_INTEGER(BIO *bp, ASN1_INTEGER *a);
|
|
int a2i_ASN1_INTEGER(BIO *bp,ASN1_INTEGER *bs,char *buf,int size);
|
|
|
|
int ASN1_INTEGER_set(ASN1_INTEGER *a, long v);
|
|
long ASN1_INTEGER_get(ASN1_INTEGER *a);
|
|
ASN1_INTEGER *BN_to_ASN1_INTEGER(BIGNUM *bn, ASN1_INTEGER *ai);
|
|
BIGNUM *ASN1_INTEGER_to_BN(ASN1_INTEGER *ai,BIGNUM *bn);
|
|
|
|
/* given a string, return the correct type. Max is the maximum number
|
|
* of bytes to parse. It stops parsing when 'max' bytes have been
|
|
* processed or a '\0' is hit */
|
|
int ASN1_PRINTABLE_type(unsigned char *s,int max);
|
|
|
|
void ASN1_parse(BIO *fp,unsigned char *pp,long len);
|
|
|
|
int i2d_ASN1_bytes(ASN1_BIT_STRING *a, unsigned char **pp, int tag, int class);
|
|
ASN1_BIT_STRING *d2i_ASN1_bytes(ASN1_OCTET_STRING **a, unsigned char **pp,
|
|
long length, int Ptag, int Pclass);
|
|
|
|
/* PARSING */
|
|
int asn1_Finish(ASN1_CTX *c);
|
|
|
|
/* SPECIALS */
|
|
int ASN1_get_object(unsigned char **pp, long *plength, int *ptag,
|
|
int *pclass, long omax);
|
|
int ASN1_check_infinite_end(unsigned char **p,long len);
|
|
void ASN1_put_object(unsigned char **pp, int constructed, int length,
|
|
int tag, int class);
|
|
int ASN1_object_size(int constructed, int length, int tag);
|
|
|
|
X509 * X509_get_cert(CERTIFICATE_CTX *ctx,X509_NAME * name,X509 *tmp_x509);
|
|
int X509_add_cert(CERTIFICATE_CTX *ctx,X509 *);
|
|
|
|
char * X509_cert_verify_error_string(int n);
|
|
int X509_add_cert_file(CERTIFICATE_CTX *c,char *file, int type);
|
|
char * X509_gmtime (char *s, long adj);
|
|
int X509_add_cert_dir (CERTIFICATE_CTX *c,char *dir, int type);
|
|
int X509_load_verify_locations (CERTIFICATE_CTX *ctx,
|
|
char *file_env, char *dir_env);
|
|
int X509_set_default_verify_paths(CERTIFICATE_CTX *cts);
|
|
X509 * X509_new_D2i_X509(int len, unsigned char *p);
|
|
char * X509_get_default_cert_area(void );
|
|
char * X509_get_default_cert_dir(void );
|
|
char * X509_get_default_cert_file(void );
|
|
char * X509_get_default_cert_dir_env(void );
|
|
char * X509_get_default_cert_file_env(void );
|
|
char * X509_get_default_private_dir(void );
|
|
X509_REQ *X509_X509_TO_req(X509 *x, RSA *rsa);
|
|
int X509_cert_verify(CERTIFICATE_CTX *ctx,X509 *xs, int (*cb)());
|
|
|
|
CERTIFICATE_CTX *CERTIFICATE_CTX_new();
|
|
void CERTIFICATE_CTX_free(CERTIFICATE_CTX *c);
|
|
|
|
void X509_NAME_print(BIO *fp, X509_NAME *name, int obase);
|
|
int X509_print_fp(FILE *fp,X509 *x);
|
|
int X509_print(BIO *fp,X509 *x);
|
|
|
|
X509_INFO * X509_INFO_new(void);
|
|
void X509_INFO_free(X509_INFO *a);
|
|
|
|
char * X509_NAME_oneline(X509_NAME *a);
|
|
|
|
#define X509_verify(x,rsa)
|
|
#define X509_REQ_verify(x,rsa)
|
|
#define X509_CRL_verify(x,rsa)
|
|
|
|
#define X509_sign(x,rsa,md)
|
|
#define X509_REQ_sign(x,rsa,md)
|
|
#define X509_CRL_sign(x,rsa,md)
|
|
|
|
#define X509_dup(x509)
|
|
#define d2i_X509_fp(fp,x509)
|
|
#define i2d_X509_fp(fp,x509)
|
|
#define d2i_X509_bio(bp,x509)
|
|
#define i2d_X509_bio(bp,x509)
|
|
|
|
#define X509_CRL_dup(crl)
|
|
#define d2i_X509_CRL_fp(fp,crl)
|
|
#define i2d_X509_CRL_fp(fp,crl)
|
|
#define d2i_X509_CRL_bio(bp,crl)
|
|
#define i2d_X509_CRL_bio(bp,crl)
|
|
|
|
#define X509_REQ_dup(req)
|
|
#define d2i_X509_REQ_fp(fp,req)
|
|
#define i2d_X509_REQ_fp(fp,req)
|
|
#define d2i_X509_REQ_bio(bp,req)
|
|
#define i2d_X509_REQ_bio(bp,req)
|
|
|
|
#define RSAPrivateKey_dup(rsa)
|
|
#define d2i_RSAPrivateKey_fp(fp,rsa)
|
|
#define i2d_RSAPrivateKey_fp(fp,rsa)
|
|
#define d2i_RSAPrivateKey_bio(bp,rsa)
|
|
#define i2d_RSAPrivateKey_bio(bp,rsa)
|
|
|
|
#define X509_NAME_dup(xn)
|
|
#define X509_NAME_ENTRY_dup(ne)
|
|
|
|
void X509_REQ_print_fp(FILE *fp,X509_REQ *req);
|
|
void X509_REQ_print(BIO *fp,X509_REQ *req);
|
|
|
|
RSA *X509_REQ_extract_key(X509_REQ *req);
|
|
RSA *X509_extract_key(X509 *x509);
|
|
|
|
int X509_issuer_and_serial_cmp(X509 *a, X509 *b);
|
|
unsigned long X509_issuer_and_serial_hash(X509 *a);
|
|
|
|
X509_NAME * X509_get_issuer_name(X509 *a);
|
|
int X509_issuer_name_cmp(X509 *a, X509 *b);
|
|
unsigned long X509_issuer_name_hash(X509 *a);
|
|
|
|
X509_NAME * X509_get_subject_name(X509 *a);
|
|
int X509_subject_name_cmp(X509 *a,X509 *b);
|
|
unsigned long X509_subject_name_hash(X509 *x);
|
|
|
|
int X509_NAME_cmp (X509_NAME *a, X509_NAME *b);
|
|
unsigned long X509_NAME_hash(X509_NAME *x);
|
|
|
|
|
|
==== bio.doc ========================================================
|
|
|
|
BIO Routines
|
|
|
|
This documentation is rather sparse, you are probably best
|
|
off looking at the code for specific details.
|
|
|
|
The BIO library is a IO abstraction that was originally
|
|
inspired by the need to have callbacks to perform IO to FILE
|
|
pointers when using Windows 3.1 DLLs. There are two types
|
|
of BIO; a source/sink type and a filter type.
|
|
The source/sink methods are as follows:
|
|
- BIO_s_mem() memory buffer - a read/write byte array that
|
|
grows until memory runs out :-).
|
|
- BIO_s_file() FILE pointer - A wrapper around the normal
|
|
'FILE *' commands, good for use with stdin/stdout.
|
|
- BIO_s_fd() File descriptor - A wrapper around file
|
|
descriptors, often used with pipes.
|
|
- BIO_s_socket() Socket - Used around sockets. It is
|
|
mostly in the Microsoft world that sockets are different
|
|
from file descriptors and there are all those ugly winsock
|
|
commands.
|
|
- BIO_s_null() Null - read nothing and write nothing.; a
|
|
useful endpoint for filter type BIO's specifically things
|
|
like the message digest BIO.
|
|
|
|
The filter types are
|
|
- BIO_f_buffer() IO buffering - does output buffering into
|
|
larger chunks and performs input buffering to allow gets()
|
|
type functions.
|
|
- BIO_f_md() Message digest - a transparent filter that can
|
|
be asked to return a message digest for the data that has
|
|
passed through it.
|
|
- BIO_f_cipher() Encrypt or decrypt all data passing
|
|
through the filter.
|
|
- BIO_f_base64() Base64 decode on read and encode on write.
|
|
- BIO_f_ssl() A filter that performs SSL encryption on the
|
|
data sent through it.
|
|
|
|
Base BIO functions.
|
|
The BIO library has a set of base functions that are
|
|
implemented for each particular type. Filter BIOs will
|
|
normally call the equivalent function on the source/sink BIO
|
|
that they are layered on top of after they have performed
|
|
some modification to the data stream. Multiple filter BIOs
|
|
can be 'push' into a stack of modifers, so to read from a
|
|
file, unbase64 it, then decrypt it, a BIO_f_cipher,
|
|
BIO_f_base64 and a BIO_s_file would probably be used. If a
|
|
sha-1 and md5 message digest needed to be generated, a stack
|
|
two BIO_f_md() BIOs and a BIO_s_null() BIO could be used.
|
|
The base functions are
|
|
- BIO *BIO_new(BIO_METHOD *type); Create a new BIO of type 'type'.
|
|
- int BIO_free(BIO *a); Free a BIO structure. Depending on
|
|
the configuration, this will free the underlying data
|
|
object for a source/sink BIO.
|
|
- int BIO_read(BIO *b, char *data, int len); Read upto 'len'
|
|
bytes into 'data'.
|
|
- int BIO_gets(BIO *bp,char *buf, int size); Depending on
|
|
the BIO, this can either be a 'get special' or a get one
|
|
line of data, as per fgets();
|
|
- int BIO_write(BIO *b, char *data, int len); Write 'len'
|
|
bytes from 'data' to the 'b' BIO.
|
|
- int BIO_puts(BIO *bp,char *buf); Either a 'put special' or
|
|
a write null terminated string as per fputs().
|
|
- long BIO_ctrl(BIO *bp,int cmd,long larg,char *parg); A
|
|
control function which is used to manipulate the BIO
|
|
structure and modify it's state and or report on it. This
|
|
function is just about never used directly, rather it
|
|
should be used in conjunction with BIO_METHOD specific
|
|
macros.
|
|
- BIO *BIO_push(BIO *new_top, BIO *old); new_top is apped to the
|
|
top of the 'old' BIO list. new_top should be a filter BIO.
|
|
All writes will go through 'new_top' first and last on read.
|
|
'old' is returned.
|
|
- BIO *BIO_pop(BIO *bio); the new topmost BIO is returned, NULL if
|
|
there are no more.
|
|
|
|
If a particular low level BIO method is not supported
|
|
(normally BIO_gets()), -2 will be returned if that method is
|
|
called. Otherwise the IO methods (read, write, gets, puts)
|
|
will return the number of bytes read or written, and 0 or -1
|
|
for error (or end of input). For the -1 case,
|
|
BIO_should_retry(bio) can be called to determine if it was a
|
|
genuine error or a temporary problem. -2 will also be
|
|
returned if the BIO has not been initalised yet, in all
|
|
cases, the correct error codes are set (accessible via the
|
|
ERR library).
|
|
|
|
|
|
The following functions are convenience functions:
|
|
- int BIO_printf(BIO *bio, char * format, ..); printf but
|
|
to a BIO handle.
|
|
- long BIO_ctrl_int(BIO *bp,int cmd,long larg,int iarg); a
|
|
convenience function to allow a different argument types
|
|
to be passed to BIO_ctrl().
|
|
- int BIO_dump(BIO *b,char *bytes,int len); output 'len'
|
|
bytes from 'bytes' in a hex dump debug format.
|
|
- long BIO_debug_callback(BIO *bio, int cmd, char *argp, int
|
|
argi, long argl, long ret) - a default debug BIO callback,
|
|
this is mentioned below. To use this one normally has to
|
|
use the BIO_set_callback_arg() function to assign an
|
|
output BIO for the callback to use.
|
|
- BIO *BIO_find_type(BIO *bio,int type); when there is a 'stack'
|
|
of BIOs, this function scan the list and returns the first
|
|
that is of type 'type', as listed in buffer.h under BIO_TYPE_XXX.
|
|
- void BIO_free_all(BIO *bio); Free the bio and all other BIOs
|
|
in the list. It walks the bio->next_bio list.
|
|
|
|
|
|
|
|
Extra commands are normally implemented as macros calling BIO_ctrl().
|
|
- BIO_number_read(BIO *bio) - the number of bytes processed
|
|
by BIO_read(bio,.).
|
|
- BIO_number_written(BIO *bio) - the number of bytes written
|
|
by BIO_write(bio,.).
|
|
- BIO_reset(BIO *bio) - 'reset' the BIO.
|
|
- BIO_eof(BIO *bio) - non zero if we are at the current end
|
|
of input.
|
|
- BIO_set_close(BIO *bio, int close_flag) - set the close flag.
|
|
- BIO_get_close(BIO *bio) - return the close flag.
|
|
BIO_pending(BIO *bio) - return the number of bytes waiting
|
|
to be read (normally buffered internally).
|
|
- BIO_flush(BIO *bio) - output any data waiting to be output.
|
|
- BIO_should_retry(BIO *io) - after a BIO_read/BIO_write
|
|
operation returns 0 or -1, a call to this function will
|
|
return non zero if you should retry the call later (this
|
|
is for non-blocking IO).
|
|
- BIO_should_read(BIO *io) - we should retry when data can
|
|
be read.
|
|
- BIO_should_write(BIO *io) - we should retry when data can
|
|
be written.
|
|
- BIO_method_name(BIO *io) - return a string for the method name.
|
|
- BIO_method_type(BIO *io) - return the unique ID of the BIO method.
|
|
- BIO_set_callback(BIO *io, long (*callback)(BIO *io, int
|
|
cmd, char *argp, int argi, long argl, long ret); - sets
|
|
the debug callback.
|
|
- BIO_get_callback(BIO *io) - return the assigned function
|
|
as mentioned above.
|
|
- BIO_set_callback_arg(BIO *io, char *arg) - assign some
|
|
data against the BIO. This is normally used by the debug
|
|
callback but could in reality be used for anything. To
|
|
get an idea of how all this works, have a look at the code
|
|
in the default debug callback mentioned above. The
|
|
callback can modify the return values.
|
|
|
|
Details of the BIO_METHOD structure.
|
|
typedef struct bio_method_st
|
|
{
|
|
int type;
|
|
char *name;
|
|
int (*bwrite)();
|
|
int (*bread)();
|
|
int (*bputs)();
|
|
int (*bgets)();
|
|
long (*ctrl)();
|
|
int (*create)();
|
|
int (*destroy)();
|
|
} BIO_METHOD;
|
|
|
|
The 'type' is the numeric type of the BIO, these are listed in buffer.h;
|
|
'Name' is a textual representation of the BIO 'type'.
|
|
The 7 function pointers point to the respective function
|
|
methods, some of which can be NULL if not implemented.
|
|
The BIO structure
|
|
typedef struct bio_st
|
|
{
|
|
BIO_METHOD *method;
|
|
long (*callback)(BIO * bio, int mode, char *argp, int
|
|
argi, long argl, long ret);
|
|
char *cb_arg; /* first argument for the callback */
|
|
int init;
|
|
int shutdown;
|
|
int flags; /* extra storage */
|
|
int num;
|
|
char *ptr;
|
|
struct bio_st *next_bio; /* used by filter BIOs */
|
|
int references;
|
|
unsigned long num_read;
|
|
unsigned long num_write;
|
|
} BIO;
|
|
|
|
- 'Method' is the BIO method.
|
|
- 'callback', when configured, is called before and after
|
|
each BIO method is called for that particular BIO. This
|
|
is intended primarily for debugging and of informational feedback.
|
|
- 'init' is 0 when the BIO can be used for operation.
|
|
Often, after a BIO is created, a number of operations may
|
|
need to be performed before it is available for use. An
|
|
example is for BIO_s_sock(). A socket needs to be
|
|
assigned to the BIO before it can be used.
|
|
- 'shutdown', this flag indicates if the underlying
|
|
comunication primative being used should be closed/freed
|
|
when the BIO is closed.
|
|
- 'flags' is used to hold extra state. It is primarily used
|
|
to hold information about why a non-blocking operation
|
|
failed and to record startup protocol information for the
|
|
SSL BIO.
|
|
- 'num' and 'ptr' are used to hold instance specific state
|
|
like file descriptors or local data structures.
|
|
- 'next_bio' is used by filter BIOs to hold the pointer of the
|
|
next BIO in the chain. written data is sent to this BIO and
|
|
data read is taken from it.
|
|
- 'references' is used to indicate the number of pointers to
|
|
this structure. This needs to be '1' before a call to
|
|
BIO_free() is made if the BIO_free() function is to
|
|
actually free() the structure, otherwise the reference
|
|
count is just decreased. The actual BIO subsystem does
|
|
not really use this functionality but it is useful when
|
|
used in more advanced applicaion.
|
|
- num_read and num_write are the total number of bytes
|
|
read/written via the 'read()' and 'write()' methods.
|
|
|
|
BIO_ctrl operations.
|
|
The following is the list of standard commands passed as the
|
|
second parameter to BIO_ctrl() and should be supported by
|
|
all BIO as best as possible. Some are optional, some are
|
|
manditory, in any case, where is makes sense, a filter BIO
|
|
should pass such requests to underlying BIO's.
|
|
- BIO_CTRL_RESET - Reset the BIO back to an initial state.
|
|
- BIO_CTRL_EOF - return 0 if we are not at the end of input,
|
|
non 0 if we are.
|
|
- BIO_CTRL_INFO - BIO specific special command, normal
|
|
information return.
|
|
- BIO_CTRL_SET - set IO specific parameter.
|
|
- BIO_CTRL_GET - get IO specific parameter.
|
|
- BIO_CTRL_GET_CLOSE - Get the close on BIO_free() flag, one
|
|
of BIO_CLOSE or BIO_NOCLOSE.
|
|
- BIO_CTRL_SET_CLOSE - Set the close on BIO_free() flag.
|
|
- BIO_CTRL_PENDING - Return the number of bytes available
|
|
for instant reading
|
|
- BIO_CTRL_FLUSH - Output pending data, return number of bytes output.
|
|
- BIO_CTRL_SHOULD_RETRY - After an IO error (-1 returned)
|
|
should we 'retry' when IO is possible on the underlying IO object.
|
|
- BIO_CTRL_RETRY_TYPE - What kind of IO are we waiting on.
|
|
|
|
The following command is a special BIO_s_file() specific option.
|
|
- BIO_CTRL_SET_FILENAME - specify a file to open for IO.
|
|
|
|
The BIO_CTRL_RETRY_TYPE needs a little more explanation.
|
|
When performing non-blocking IO, or say reading on a memory
|
|
BIO, when no data is present (or cannot be written),
|
|
BIO_read() and/or BIO_write() will return -1.
|
|
BIO_should_retry(bio) will return true if this is due to an
|
|
IO condition rather than an actual error. In the case of
|
|
BIO_s_mem(), a read when there is no data will return -1 and
|
|
a should retry when there is more 'read' data.
|
|
The retry type is deduced from 2 macros
|
|
BIO_should_read(bio) and BIO_should_write(bio).
|
|
Now while it may appear obvious that a BIO_read() failure
|
|
should indicate that a retry should be performed when more
|
|
read data is available, this is often not true when using
|
|
things like an SSL BIO. During the SSL protocol startup
|
|
multiple reads and writes are performed, triggered by any
|
|
SSL_read or SSL_write.
|
|
So to write code that will transparently handle either a
|
|
socket or SSL BIO,
|
|
i=BIO_read(bio,..)
|
|
if (I == -1)
|
|
{
|
|
if (BIO_should_retry(bio))
|
|
{
|
|
if (BIO_should_read(bio))
|
|
{
|
|
/* call us again when BIO can be read */
|
|
}
|
|
if (BIO_should_write(bio))
|
|
{
|
|
/* call us again when BIO can be written */
|
|
}
|
|
}
|
|
}
|
|
|
|
At this point in time only read and write conditions can be
|
|
used but in the future I can see the situation for other
|
|
conditions, specifically with SSL there could be a condition
|
|
of a X509 certificate lookup taking place and so the non-
|
|
blocking BIO_read would require a retry when the certificate
|
|
lookup subsystem has finished it's lookup. This is all
|
|
makes more sense and is easy to use in a event loop type
|
|
setup.
|
|
When using the SSL BIO, either SSL_read() or SSL_write()s
|
|
can be called during the protocol startup and things will
|
|
still work correctly.
|
|
The nice aspect of the use of the BIO_should_retry() macro
|
|
is that all the errno codes that indicate a non-fatal error
|
|
are encapsulated in one place. The Windows specific error
|
|
codes and WSAGetLastError() calls are also hidden from the
|
|
application.
|
|
|
|
Notes on each BIO method.
|
|
Normally buffer.h is just required but depending on the
|
|
BIO_METHOD, ssl.h or evp.h will also be required.
|
|
|
|
BIO_METHOD *BIO_s_mem(void);
|
|
- BIO_set_mem_buf(BIO *bio, BUF_MEM *bm, int close_flag) -
|
|
set the underlying BUF_MEM structure for the BIO to use.
|
|
- BIO_get_mem_ptr(BIO *bio, char **pp) - if pp is not NULL,
|
|
set it to point to the memory array and return the number
|
|
of bytes available.
|
|
A read/write BIO. Any data written is appended to the
|
|
memory array and any read is read from the front. This BIO
|
|
can be used for read/write at the same time. BIO_gets() is
|
|
supported in the fgets() sense.
|
|
BIO_CTRL_INFO can be used to retrieve pointers to the memory
|
|
buffer and it's length.
|
|
|
|
BIO_METHOD *BIO_s_file(void);
|
|
- BIO_set_fp(BIO *bio, FILE *fp, int close_flag) - set 'FILE *' to use.
|
|
- BIO_get_fp(BIO *bio, FILE **fp) - get the 'FILE *' in use.
|
|
- BIO_read_filename(BIO *bio, char *name) - read from file.
|
|
- BIO_write_filename(BIO *bio, char *name) - write to file.
|
|
- BIO_append_filename(BIO *bio, char *name) - append to file.
|
|
This BIO sits over the normal system fread()/fgets() type
|
|
functions. Gets() is supported. This BIO in theory could be
|
|
used for read and write but it is best to think of each BIO
|
|
of this type as either a read or a write BIO, not both.
|
|
|
|
BIO_METHOD *BIO_s_socket(void);
|
|
BIO_METHOD *BIO_s_fd(void);
|
|
- BIO_sock_should_retry(int i) - the underlying function
|
|
used to determine if a call should be retried; the
|
|
argument is the '0' or '-1' returned by the previous BIO
|
|
operation.
|
|
- BIO_fd_should_retry(int i) - same as the
|
|
- BIO_sock_should_retry() except that it is different internally.
|
|
- BIO_set_fd(BIO *bio, int fd, int close_flag) - set the
|
|
file descriptor to use
|
|
- BIO_get_fd(BIO *bio, int *fd) - get the file descriptor.
|
|
These two methods are very similar. Gets() is not
|
|
supported, if you want this functionality, put a
|
|
BIO_f_buffer() onto it. This BIO is bi-directional if the
|
|
underlying file descriptor is. This is normally the case
|
|
for sockets but not the case for stdio descriptors.
|
|
|
|
BIO_METHOD *BIO_s_null(void);
|
|
Read and write as much data as you like, it all disappears
|
|
into this BIO.
|
|
|
|
BIO_METHOD *BIO_f_buffer(void);
|
|
- BIO_get_buffer_num_lines(BIO *bio) - return the number of
|
|
complete lines in the buffer.
|
|
- BIO_set_buffer_size(BIO *bio, long size) - set the size of
|
|
the buffers.
|
|
This type performs input and output buffering. It performs
|
|
both at the same time. The size of the buffer can be set
|
|
via the set buffer size option. Data buffered for output is
|
|
only written when the buffer fills.
|
|
|
|
BIO_METHOD *BIO_f_ssl(void);
|
|
- BIO_set_ssl(BIO *bio, SSL *ssl, int close_flag) - the SSL
|
|
structure to use.
|
|
- BIO_get_ssl(BIO *bio, SSL **ssl) - get the SSL structure
|
|
in use.
|
|
The SSL bio is a little different from normal BIOs because
|
|
the underlying SSL structure is a little different. A SSL
|
|
structure performs IO via a read and write BIO. These can
|
|
be different and are normally set via the
|
|
SSL_set_rbio()/SSL_set_wbio() calls. The SSL_set_fd() calls
|
|
are just wrappers that create socket BIOs and then call
|
|
SSL_set_bio() where the read and write BIOs are the same.
|
|
The BIO_push() operation makes the SSLs IO BIOs the same, so
|
|
make sure the BIO pushed is capable of two directional
|
|
traffic. If it is not, you will have to install the BIOs
|
|
via the more conventional SSL_set_bio() call. BIO_pop() will retrieve
|
|
the 'SSL read' BIO.
|
|
|
|
BIO_METHOD *BIO_f_md(void);
|
|
- BIO_set_md(BIO *bio, EVP_MD *md) - set the message digest
|
|
to use.
|
|
- BIO_get_md(BIO *bio, EVP_MD **mdp) - return the digest
|
|
method in use in mdp, return 0 if not set yet.
|
|
- BIO_reset() reinitializes the digest (EVP_DigestInit())
|
|
and passes the reset to the underlying BIOs.
|
|
All data read or written via BIO_read() or BIO_write() to
|
|
this BIO will be added to the calculated digest. This
|
|
implies that this BIO is only one directional. If read and
|
|
write operations are performed, two separate BIO_f_md() BIOs
|
|
are reuqired to generate digests on both the input and the
|
|
output. BIO_gets(BIO *bio, char *md, int size) will place the
|
|
generated digest into 'md' and return the number of bytes.
|
|
The EVP_MAX_MD_SIZE should probably be used to size the 'md'
|
|
array. Reading the digest will also reset it.
|
|
|
|
BIO_METHOD *BIO_f_cipher(void);
|
|
- BIO_reset() reinitializes the cipher.
|
|
- BIO_flush() should be called when the last bytes have been
|
|
output to flush the final block of block ciphers.
|
|
- BIO_get_cipher_status(BIO *b), when called after the last
|
|
read from a cipher BIO, returns non-zero if the data
|
|
decrypted correctly, otherwise, 0.
|
|
- BIO_set_cipher(BIO *b, EVP_CIPHER *c, unsigned char *key,
|
|
unsigned char *iv, int encrypt) This function is used to
|
|
setup a cipher BIO. The length of key and iv are
|
|
specified by the choice of EVP_CIPHER. Encrypt is 1 to
|
|
encrypt and 0 to decrypt.
|
|
|
|
BIO_METHOD *BIO_f_base64(void);
|
|
- BIO_flush() should be called when the last bytes have been output.
|
|
This BIO base64 encodes when writing and base64 decodes when
|
|
reading. It will scan the input until a suitable begin line
|
|
is found. After reading data, BIO_reset() will reset the
|
|
BIO to start scanning again. Do not mix reading and writing
|
|
on the same base64 BIO. It is meant as a single stream BIO.
|
|
|
|
Directions type
|
|
both BIO_s_mem()
|
|
one/both BIO_s_file()
|
|
both BIO_s_fd()
|
|
both BIO_s_socket()
|
|
both BIO_s_null()
|
|
both BIO_f_buffer()
|
|
one BIO_f_md()
|
|
one BIO_f_cipher()
|
|
one BIO_f_base64()
|
|
both BIO_f_ssl()
|
|
|
|
It is easy to mix one and two directional BIOs, all one has
|
|
to do is to keep two separate BIO pointers for reading and
|
|
writing and be careful about usage of underlying BIOs. The
|
|
SSL bio by it's very nature has to be two directional but
|
|
the BIO_push() command will push the one BIO into the SSL
|
|
BIO for both reading and writing.
|
|
|
|
The best example program to look at is apps/enc.c and/or perhaps apps/dgst.c.
|
|
|
|
|
|
==== blowfish.doc ========================================================
|
|
|
|
The Blowfish library.
|
|
|
|
Blowfish is a block cipher that operates on 64bit (8 byte) quantities. It
|
|
uses variable size key, but 128bit (16 byte) key would normally be considered
|
|
good. It can be used in all the modes that DES can be used. This
|
|
library implements the ecb, cbc, cfb64, ofb64 modes.
|
|
|
|
Blowfish is quite a bit faster that DES, and much faster than IDEA or
|
|
RC2. It is one of the faster block ciphers.
|
|
|
|
For all calls that have an 'input' and 'output' variables, they can be the
|
|
same.
|
|
|
|
This library requires the inclusion of 'blowfish.h'.
|
|
|
|
All of the encryption functions take what is called an BF_KEY as an
|
|
argument. An BF_KEY is an expanded form of the Blowfish key.
|
|
For all modes of the Blowfish algorithm, the BF_KEY used for
|
|
decryption is the same one that was used for encryption.
|
|
|
|
The define BF_ENCRYPT is passed to specify encryption for the functions
|
|
that require an encryption/decryption flag. BF_DECRYPT is passed to
|
|
specify decryption.
|
|
|
|
Please note that any of the encryption modes specified in my DES library
|
|
could be used with Blowfish. I have only implemented ecb, cbc, cfb64 and
|
|
ofb64 for the following reasons.
|
|
- ecb is the basic Blowfish encryption.
|
|
- cbc is the normal 'chaining' form for block ciphers.
|
|
- cfb64 can be used to encrypt single characters, therefore input and output
|
|
do not need to be a multiple of 8.
|
|
- ofb64 is similar to cfb64 but is more like a stream cipher, not as
|
|
secure (not cipher feedback) but it does not have an encrypt/decrypt mode.
|
|
- If you want triple Blowfish, thats 384 bits of key and you must be totally
|
|
obsessed with security. Still, if you want it, it is simple enough to
|
|
copy the function from the DES library and change the des_encrypt to
|
|
BF_encrypt; an exercise left for the paranoid reader :-).
|
|
|
|
The functions are as follows:
|
|
|
|
void BF_set_key(
|
|
BF_KEY *ks;
|
|
int len;
|
|
unsigned char *key;
|
|
BF_set_key converts an 'len' byte key into a BF_KEY.
|
|
A 'ks' is an expanded form of the 'key' which is used to
|
|
perform actual encryption. It can be regenerated from the Blowfish key
|
|
so it only needs to be kept when encryption or decryption is about
|
|
to occur. Don't save or pass around BF_KEY's since they
|
|
are CPU architecture dependent, 'key's are not. Blowfish is an
|
|
interesting cipher in that it can be used with a variable length
|
|
key. 'len' is the length of 'key' to be used as the key.
|
|
A 'len' of 16 is recomended by me, but blowfish can use upto
|
|
72 bytes. As a warning, blowfish has a very very slow set_key
|
|
function, it actually runs BF_encrypt 521 times.
|
|
|
|
void BF_encrypt(unsigned long *data, BF_KEY *key);
|
|
void BF_decrypt(unsigned long *data, BF_KEY *key);
|
|
These are the Blowfish encryption function that gets called by just
|
|
about every other Blowfish routine in the library. You should not
|
|
use this function except to implement 'modes' of Blowfish.
|
|
I say this because the
|
|
functions that call this routine do the conversion from 'char *' to
|
|
long, and this needs to be done to make sure 'non-aligned' memory
|
|
access do not occur.
|
|
Data is a pointer to 2 unsigned long's and key is the
|
|
BF_KEY to use.
|
|
|
|
void BF_ecb_encrypt(
|
|
unsigned char *in,
|
|
unsigned char *out,
|
|
BF_KEY *key,
|
|
int encrypt);
|
|
This is the basic Electronic Code Book form of Blowfish (in DES this
|
|
mode is called Electronic Code Book so I'm going to use the term
|
|
for blowfish as well.
|
|
Input is encrypted into output using the key represented by
|
|
key. Depending on the encrypt, encryption or
|
|
decryption occurs. Input is 8 bytes long and output is 8 bytes.
|
|
|
|
void BF_cbc_encrypt(
|
|
unsigned char *in,
|
|
unsigned char *out,
|
|
long length,
|
|
BF_KEY *ks,
|
|
unsigned char *ivec,
|
|
int encrypt);
|
|
This routine implements Blowfish in Cipher Block Chaining mode.
|
|
Input, which should be a multiple of 8 bytes is encrypted
|
|
(or decrypted) to output which will also be a multiple of 8 bytes.
|
|
The number of bytes is in length (and from what I've said above,
|
|
should be a multiple of 8). If length is not a multiple of 8, bad
|
|
things will probably happen. ivec is the initialisation vector.
|
|
This function updates iv after each call so that it can be passed to
|
|
the next call to BF_cbc_encrypt().
|
|
|
|
void BF_cfb64_encrypt(
|
|
unsigned char *in,
|
|
unsigned char *out,
|
|
long length,
|
|
BF_KEY *schedule,
|
|
unsigned char *ivec,
|
|
int *num,
|
|
int encrypt);
|
|
This is one of the more useful functions in this Blowfish library, it
|
|
implements CFB mode of Blowfish with 64bit feedback.
|
|
This allows you to encrypt an arbitrary number of bytes,
|
|
you do not require 8 byte padding. Each call to this
|
|
routine will encrypt the input bytes to output and then update ivec
|
|
and num. Num contains 'how far' we are though ivec.
|
|
'Encrypt' is used to indicate encryption or decryption.
|
|
CFB64 mode operates by using the cipher to generate a stream
|
|
of bytes which is used to encrypt the plain text.
|
|
The cipher text is then encrypted to generate the next 64 bits to
|
|
be xored (incrementally) with the next 64 bits of plain
|
|
text. As can be seen from this, to encrypt or decrypt,
|
|
the same 'cipher stream' needs to be generated but the way the next
|
|
block of data is gathered for encryption is different for
|
|
encryption and decryption.
|
|
|
|
void BF_ofb64_encrypt(
|
|
unsigned char *in,
|
|
unsigned char *out,
|
|
long length,
|
|
BF_KEY *schedule,
|
|
unsigned char *ivec,
|
|
int *num);
|
|
This functions implements OFB mode of Blowfish with 64bit feedback.
|
|
This allows you to encrypt an arbitrary number of bytes,
|
|
you do not require 8 byte padding. Each call to this
|
|
routine will encrypt the input bytes to output and then update ivec
|
|
and num. Num contains 'how far' we are though ivec.
|
|
This is in effect a stream cipher, there is no encryption or
|
|
decryption mode.
|
|
|
|
For reading passwords, I suggest using des_read_pw_string() from my DES library.
|
|
To generate a password from a text string, I suggest using MD5 (or MD2) to
|
|
produce a 16 byte message digest that can then be passed directly to
|
|
BF_set_key().
|
|
|
|
=====
|
|
For more information about the specific Blowfish modes in this library
|
|
(ecb, cbc, cfb and ofb), read the section entitled 'Modes of DES' from the
|
|
documentation on my DES library. What is said about DES is directly
|
|
applicable for Blowfish.
|
|
|
|
|
|
==== bn.doc ========================================================
|
|
|
|
The Big Number library.
|
|
|
|
#include "bn.h" when using this library.
|
|
|
|
This big number library was written for use in implementing the RSA and DH
|
|
public key encryption algorithms. As such, features such as negative
|
|
numbers have not been extensively tested but they should work as expected.
|
|
This library uses dynamic memory allocation for storing its data structures
|
|
and so there are no limit on the size of the numbers manipulated by these
|
|
routines but there is always the requirement to check return codes from
|
|
functions just in case a memory allocation error has occurred.
|
|
|
|
The basic object in this library is a BIGNUM. It is used to hold a single
|
|
large integer. This type should be considered opaque and fields should not
|
|
be modified or accessed directly.
|
|
typedef struct bignum_st
|
|
{
|
|
int top; /* Index of last used d. */
|
|
BN_ULONG *d; /* Pointer to an array of 'BITS2' bit chunks. */
|
|
int max; /* Size of the d array. */
|
|
int neg;
|
|
} BIGNUM;
|
|
The big number is stored in a malloced array of BN_ULONG's. A BN_ULONG can
|
|
be either 16, 32 or 64 bits in size, depending on the 'number of bits'
|
|
specified in bn.h.
|
|
The 'd' field is this array. 'max' is the size of the 'd' array that has
|
|
been allocated. 'top' is the 'last' entry being used, so for a value of 4,
|
|
bn.d[0]=4 and bn.top=1. 'neg' is 1 if the number is negative.
|
|
When a BIGNUM is '0', the 'd' field can be NULL and top == 0.
|
|
|
|
Various routines in this library require the use of 'temporary' BIGNUM
|
|
variables during their execution. Due to the use of dynamic memory
|
|
allocation to create BIGNUMs being rather expensive when used in
|
|
conjunction with repeated subroutine calls, the BN_CTX structure is
|
|
used. This structure contains BN_CTX BIGNUMs. BN_CTX
|
|
is the maximum number of temporary BIGNUMs any publicly exported
|
|
function will use.
|
|
|
|
#define BN_CTX 12
|
|
typedef struct bignum_ctx
|
|
{
|
|
int tos; /* top of stack */
|
|
BIGNUM *bn[BN_CTX]; /* The variables */
|
|
} BN_CTX;
|
|
|
|
The functions that follow have been grouped according to function. Most
|
|
arithmetic functions return a result in the first argument, sometimes this
|
|
first argument can also be an input parameter, sometimes it cannot. These
|
|
restrictions are documented.
|
|
|
|
extern BIGNUM *BN_value_one;
|
|
There is one variable defined by this library, a BIGNUM which contains the
|
|
number 1. This variable is useful for use in comparisons and assignment.
|
|
|
|
Get Size functions.
|
|
|
|
int BN_num_bits(BIGNUM *a);
|
|
This function returns the size of 'a' in bits.
|
|
|
|
int BN_num_bytes(BIGNUM *a);
|
|
This function (macro) returns the size of 'a' in bytes.
|
|
For conversion of BIGNUMs to byte streams, this is the number of
|
|
bytes the output string will occupy. If the output byte
|
|
format specifies that the 'top' bit indicates if the number is
|
|
signed, so an extra '0' byte is required if the top bit on a
|
|
positive number is being written, it is upto the application to
|
|
make this adjustment. Like I said at the start, I don't
|
|
really support negative numbers :-).
|
|
|
|
Creation/Destruction routines.
|
|
|
|
BIGNUM *BN_new();
|
|
Return a new BIGNUM object. The number initially has a value of 0. If
|
|
there is an error, NULL is returned.
|
|
|
|
void BN_free(BIGNUM *a);
|
|
Free()s a BIGNUM.
|
|
|
|
void BN_clear(BIGNUM *a);
|
|
Sets 'a' to a value of 0 and also zeros all unused allocated
|
|
memory. This function is used to clear a variable of 'sensitive'
|
|
data that was held in it.
|
|
|
|
void BN_clear_free(BIGNUM *a);
|
|
This function zeros the memory used by 'a' and then free()'s it.
|
|
This function should be used to BN_free() BIGNUMS that have held
|
|
sensitive numeric values like RSA private key values. Both this
|
|
function and BN_clear tend to only be used by RSA and DH routines.
|
|
|
|
BN_CTX *BN_CTX_new(void);
|
|
Returns a new BN_CTX. NULL on error.
|
|
|
|
void BN_CTX_free(BN_CTX *c);
|
|
Free a BN_CTX structure. The BIGNUMs in 'c' are BN_clear_free()ed.
|
|
|
|
BIGNUM *bn_expand(BIGNUM *b, int bits);
|
|
This is an internal function that should not normally be used. It
|
|
ensures that 'b' has enough room for a 'bits' bit number. It is
|
|
mostly used by the various BIGNUM routines. If there is an error,
|
|
NULL is returned. if not, 'b' is returned.
|
|
|
|
BIGNUM *BN_copy(BIGNUM *to, BIGNUM *from);
|
|
The 'from' is copied into 'to'. NULL is returned if there is an
|
|
error, otherwise 'to' is returned.
|
|
|
|
BIGNUM *BN_dup(BIGNUM *a);
|
|
A new BIGNUM is created and returned containing the value of 'a'.
|
|
NULL is returned on error.
|
|
|
|
Comparison and Test Functions.
|
|
|
|
int BN_is_zero(BIGNUM *a)
|
|
Return 1 if 'a' is zero, else 0.
|
|
|
|
int BN_is_one(a)
|
|
Return 1 is 'a' is one, else 0.
|
|
|
|
int BN_is_word(a,w)
|
|
Return 1 if 'a' == w, else 0. 'w' is a BN_ULONG.
|
|
|
|
int BN_cmp(BIGNUM *a, BIGNUM *b);
|
|
Return -1 if 'a' is less than 'b', 0 if 'a' and 'b' are the same
|
|
and 1 is 'a' is greater than 'b'. This is a signed comparison.
|
|
|
|
int BN_ucmp(BIGNUM *a, BIGNUM *b);
|
|
This function is the same as BN_cmp except that the comparison
|
|
ignores the sign of the numbers.
|
|
|
|
Arithmetic Functions
|
|
For all of these functions, 0 is returned if there is an error and 1 is
|
|
returned for success. The return value should always be checked. eg.
|
|
if (!BN_add(r,a,b)) goto err;
|
|
Unless explicitly mentioned, the 'return' value can be one of the
|
|
'parameters' to the function.
|
|
|
|
int BN_add(BIGNUM *r, BIGNUM *a, BIGNUM *b);
|
|
Add 'a' and 'b' and return the result in 'r'. This is r=a+b.
|
|
|
|
int BN_sub(BIGNUM *r, BIGNUM *a, BIGNUM *b);
|
|
Subtract 'a' from 'b' and put the result in 'r'. This is r=a-b.
|
|
|
|
int BN_lshift(BIGNUM *r, BIGNUM *a, int n);
|
|
Shift 'a' left by 'n' bits. This is r=a*(2^n).
|
|
|
|
int BN_lshift1(BIGNUM *r, BIGNUM *a);
|
|
Shift 'a' left by 1 bit. This form is more efficient than
|
|
BN_lshift(r,a,1). This is r=a*2.
|
|
|
|
int BN_rshift(BIGNUM *r, BIGNUM *a, int n);
|
|
Shift 'a' right by 'n' bits. This is r=int(a/(2^n)).
|
|
|
|
int BN_rshift1(BIGNUM *r, BIGNUM *a);
|
|
Shift 'a' right by 1 bit. This form is more efficient than
|
|
BN_rshift(r,a,1). This is r=int(a/2).
|
|
|
|
int BN_mul(BIGNUM *r, BIGNUM *a, BIGNUM *b);
|
|
Multiply a by b and return the result in 'r'. 'r' must not be
|
|
either 'a' or 'b'. It has to be a different BIGNUM.
|
|
This is r=a*b.
|
|
|
|
int BN_sqr(BIGNUM *r, BIGNUM *a, BN_CTX *ctx);
|
|
Multiply a by a and return the result in 'r'. 'r' must not be
|
|
'a'. This function is alot faster than BN_mul(r,a,a). This is r=a*a.
|
|
|
|
int BN_div(BIGNUM *dv, BIGNUM *rem, BIGNUM *m, BIGNUM *d, BN_CTX *ctx);
|
|
Divide 'm' by 'd' and return the result in 'dv' and the remainder
|
|
in 'rem'. Either of 'dv' or 'rem' can be NULL in which case that
|
|
value is not returned. 'ctx' needs to be passed as a source of
|
|
temporary BIGNUM variables.
|
|
This is dv=int(m/d), rem=m%d.
|
|
|
|
int BN_mod(BIGNUM *rem, BIGNUM *m, BIGNUM *d, BN_CTX *ctx);
|
|
Find the remainder of 'm' divided by 'd' and return it in 'rem'.
|
|
'ctx' holds the temporary BIGNUMs required by this function.
|
|
This function is more efficient than BN_div(NULL,rem,m,d,ctx);
|
|
This is rem=m%d.
|
|
|
|
int BN_mod_mul(BIGNUM *r, BIGNUM *a, BIGNUM *b, BIGNUM *m,BN_CTX *ctx);
|
|
Multiply 'a' by 'b' and return the remainder when divided by 'm'.
|
|
'ctx' holds the temporary BIGNUMs required by this function.
|
|
This is r=(a*b)%m.
|
|
|
|
int BN_mod_exp(BIGNUM *r, BIGNUM *a, BIGNUM *p, BIGNUM *m,BN_CTX *ctx);
|
|
Raise 'a' to the 'p' power and return the remainder when divided by
|
|
'm'. 'ctx' holds the temporary BIGNUMs required by this function.
|
|
This is r=(a^p)%m.
|
|
|
|
int BN_reciprocal(BIGNUM *r, BIGNUM *m, BN_CTX *ctx);
|
|
Return the reciprocal of 'm'. 'ctx' holds the temporary variables
|
|
required. This function returns -1 on error, otherwise it returns
|
|
the number of bits 'r' is shifted left to make 'r' into an integer.
|
|
This number of bits shifted is required in BN_mod_mul_reciprocal().
|
|
This is r=(1/m)<<(BN_num_bits(m)+1).
|
|
|
|
int BN_mod_mul_reciprocal(BIGNUM *r, BIGNUM *x, BIGNUM *y, BIGNUM *m,
|
|
BIGNUM *i, int nb, BN_CTX *ctx);
|
|
This function is used to perform an efficient BN_mod_mul()
|
|
operation. If one is going to repeatedly perform BN_mod_mul() with
|
|
the same modulus is worth calculating the reciprocal of the modulus
|
|
and then using this function. This operation uses the fact that
|
|
a/b == a*r where r is the reciprocal of b. On modern computers
|
|
multiplication is very fast and big number division is very slow.
|
|
'x' is multiplied by 'y' and then divided by 'm' and the remainder
|
|
is returned. 'i' is the reciprocal of 'm' and 'nb' is the number
|
|
of bits as returned from BN_reciprocal(). Normal usage is as follows.
|
|
bn=BN_reciprocal(i,m);
|
|
for (...)
|
|
{ BN_mod_mul_reciprocal(r,x,y,m,i,bn,ctx); }
|
|
This is r=(x*y)%m. Internally it is approximately
|
|
r=(x*y)-m*(x*y/m) or r=(x*y)-m*((x*y*i) >> bn)
|
|
This function is used in BN_mod_exp() and BN_is_prime().
|
|
|
|
Assignment Operations
|
|
|
|
int BN_one(BIGNUM *a)
|
|
Set 'a' to hold the value one.
|
|
This is a=1.
|
|
|
|
int BN_zero(BIGNUM *a)
|
|
Set 'a' to hold the value zero.
|
|
This is a=0.
|
|
|
|
int BN_set_word(BIGNUM *a, unsigned long w);
|
|
Set 'a' to hold the value of 'w'. 'w' is an unsigned long.
|
|
This is a=w.
|
|
|
|
unsigned long BN_get_word(BIGNUM *a);
|
|
Returns 'a' in an unsigned long. Not remarkably, often 'a' will
|
|
be biger than a word, in which case 0xffffffffL is returned.
|
|
|
|
Word Operations
|
|
These functions are much more efficient that the normal bignum arithmetic
|
|
operations.
|
|
|
|
BN_ULONG BN_mod_word(BIGNUM *a, unsigned long w);
|
|
Return the remainder of 'a' divided by 'w'.
|
|
This is return(a%w).
|
|
|
|
int BN_add_word(BIGNUM *a, unsigned long w);
|
|
Add 'w' to 'a'. This function does not take the sign of 'a' into
|
|
account. This is a+=w;
|
|
|
|
Bit operations.
|
|
|
|
int BN_is_bit_set(BIGNUM *a, int n);
|
|
This function return 1 if bit 'n' is set in 'a' else 0.
|
|
|
|
int BN_set_bit(BIGNUM *a, int n);
|
|
This function sets bit 'n' to 1 in 'a'.
|
|
This is a&= ~(1<<n);
|
|
|
|
int BN_clear_bit(BIGNUM *a, int n);
|
|
This function sets bit 'n' to zero in 'a'. Return 0 if less
|
|
than 'n' bits in 'a' else 1. This is a&= ~(1<<n);
|
|
|
|
int BN_mask_bits(BIGNUM *a, int n);
|
|
Truncate 'a' to n bits long. This is a&= ~((~0)<<n)
|
|
|
|
Format conversion routines.
|
|
|
|
BIGNUM *BN_bin2bn(unsigned char *s, int len,BIGNUM *ret);
|
|
This function converts 'len' bytes in 's' into a BIGNUM which
|
|
is put in 'ret'. If ret is NULL, a new BIGNUM is created.
|
|
Either this new BIGNUM or ret is returned. The number is
|
|
assumed to be in bigendian form in 's'. By this I mean that
|
|
to 'ret' is created as follows for 'len' == 5.
|
|
ret = s[0]*2^32 + s[1]*2^24 + s[2]*2^16 + s[3]*2^8 + s[4];
|
|
This function cannot be used to convert negative numbers. It
|
|
is always assumed the number is positive. The application
|
|
needs to diddle the 'neg' field of th BIGNUM its self.
|
|
The better solution would be to save the numbers in ASN.1 format
|
|
since this is a defined standard for storing big numbers.
|
|
Look at the functions
|
|
|
|
ASN1_INTEGER *BN_to_ASN1_INTEGER(BIGNUM *bn, ASN1_INTEGER *ai);
|
|
BIGNUM *ASN1_INTEGER_to_BN(ASN1_INTEGER *ai,BIGNUM *bn);
|
|
int i2d_ASN1_INTEGER(ASN1_INTEGER *a,unsigned char **pp);
|
|
ASN1_INTEGER *d2i_ASN1_INTEGER(ASN1_INTEGER **a,unsigned char **pp,
|
|
long length;
|
|
|
|
int BN_bn2bin(BIGNUM *a, unsigned char *to);
|
|
This function converts 'a' to a byte string which is put into
|
|
'to'. The representation is big-endian in that the most
|
|
significant byte of 'a' is put into to[0]. This function
|
|
returns the number of bytes used to hold 'a'. BN_num_bytes(a)
|
|
would return the same value and can be used to determine how
|
|
large 'to' needs to be. If the number is negative, this
|
|
information is lost. Since this library was written to
|
|
manipulate large positive integers, the inability to save and
|
|
restore them is not considered to be a problem by me :-).
|
|
As for BN_bin2bn(), look at the ASN.1 integer encoding funtions
|
|
for SSLeay. They use BN_bin2bn() and BN_bn2bin() internally.
|
|
|
|
char *BN_bn2ascii(BIGNUM *a);
|
|
This function returns a malloc()ed string that contains the
|
|
ascii hexadecimal encoding of 'a'. The number is in bigendian
|
|
format with a '-' in front if the number is negative.
|
|
|
|
int BN_ascii2bn(BIGNUM **bn, char *a);
|
|
The inverse of BN_bn2ascii. The function returns the number of
|
|
characters from 'a' were processed in generating a the bignum.
|
|
error is inticated by 0 being returned. The number is a
|
|
hex digit string, optionally with a leading '-'. If *bn
|
|
is null, a BIGNUM is created and returned via that variable.
|
|
|
|
int BN_print_fp(FILE *fp, BIGNUM *a);
|
|
'a' is printed to file pointer 'fp'. It is in the same format
|
|
that is output from BN_bn2ascii(). 0 is returned on error,
|
|
1 if things are ok.
|
|
|
|
int BN_print(BIO *bp, BIGNUM *a);
|
|
Same as BN_print except that the output is done to the SSLeay libraries
|
|
BIO routines. BN_print_fp() actually calls this function.
|
|
|
|
Miscellaneous Routines.
|
|
|
|
int BN_rand(BIGNUM *rnd, int bits, int top, int bottom);
|
|
This function returns in 'rnd' a random BIGNUM that is bits
|
|
long. If bottom is 1, the number returned is odd. If top is set,
|
|
the top 2 bits of the number are set. This is useful because if
|
|
this is set, 2 'n; bit numbers multiplied together will return a 2n
|
|
bit number. If top was not set, they could produce a 2n-1 bit
|
|
number.
|
|
|
|
BIGNUM *BN_mod_inverse(BIGNUM *a, BIGNUM *n,BN_CTX *ctx);
|
|
This function create a new BIGNUM and returns it. This number
|
|
is the inverse mod 'n' of 'a'. By this it is meant that the
|
|
returned value 'r' satisfies (a*r)%n == 1. This function is
|
|
used in the generation of RSA keys. 'ctx', as per usual,
|
|
is used to hold temporary variables that are required by the
|
|
function. NULL is returned on error.
|
|
|
|
int BN_gcd(BIGNUM *r,BIGNUM *a,BIGNUM *b,BN_CTX *ctx);
|
|
'r' has the greatest common divisor of 'a' and 'b'. 'ctx' is
|
|
used for temporary variables and 0 is returned on error.
|
|
|
|
int BN_is_prime(BIGNUM *p,int nchecks,void (*callback)(),BN_CTX *ctx,
|
|
char *cb_arg);
|
|
This function is used to check if a BIGNUM ('p') is prime.
|
|
It performs this test by using the Miller-Rabin randomised
|
|
primality test. This is a probalistic test that requires a
|
|
number of rounds to ensure the number is prime to a high
|
|
degree of probability. Since this can take quite some time, a
|
|
callback function can be passed and it will be called each
|
|
time 'p' passes a round of the prime testing. 'callback' will
|
|
be called as follows, callback(1,n,cb_arg) where n is the number of
|
|
the round, just passed. As per usual 'ctx' contains temporary
|
|
variables used. If ctx is NULL, it does not matter, a local version
|
|
will be malloced. This parameter is present to save some mallocing
|
|
inside the function but probably could be removed.
|
|
0 is returned on error.
|
|
'ncheck' is the number of Miller-Rabin tests to run. It is
|
|
suggested to use the value 'BN_prime_checks' by default.
|
|
|
|
BIGNUM *BN_generate_prime(
|
|
int bits,
|
|
int strong,
|
|
BIGNUM *a,
|
|
BIGNUM *rems,
|
|
void (*callback)());
|
|
char *cb_arg
|
|
This function is used to generate prime numbers. It returns a
|
|
new BIGNUM that has a high probability of being a prime.
|
|
'bits' is the number of bits that
|
|
are to be in the prime. If 'strong' is true, the returned prime
|
|
will also be a strong prime ((p-1)/2 is also prime).
|
|
While searching for the prime ('p'), we
|
|
can add the requirement that the prime fill the following
|
|
condition p%a == rem. This can be used to help search for
|
|
primes with specific features, which is required when looking
|
|
for primes suitable for use with certain 'g' values in the
|
|
Diffie-Hellman key exchange algorithm. If 'a' is NULL,
|
|
this condition is not checked. If rem is NULL, rem is assumed
|
|
to be 1. Since this search for a prime
|
|
can take quite some time, if callback is not NULL, it is called
|
|
in the following situations.
|
|
We have a suspected prime (from a quick sieve),
|
|
callback(0,sus_prime++,cb_arg). Each item to be passed to BN_is_prime().
|
|
callback(1,round++,cb_arg). Each successful 'round' in BN_is_prime().
|
|
callback(2,round,cb_arg). For each successful BN_is_prime() test.
|
|
|
|
Hints
|
|
-----
|
|
|
|
DSA wants 64*32 to use word mont mul, but RSA wants to use full.
|
|
|
|
==== callback.doc ========================================================
|
|
|
|
Callback functions used in SSLeay.
|
|
|
|
--------------------------
|
|
The BIO library.
|
|
|
|
Each BIO structure can have a callback defined against it. This callback is
|
|
called 2 times for each BIO 'function'. It is passed 6 parameters.
|
|
BIO_debug_callback() is an example callback which is defined in
|
|
crypto/buffer/bio_cb.c and is used in apps/dgst.c This is intended mostly
|
|
for debuging or to notify the application of IO.
|
|
|
|
long BIO_debug_callback(BIO *bio,int cmd,char *argp,int argi,long argl,
|
|
long ret);
|
|
bio is the BIO being called, cmd is the type of BIO function being called.
|
|
Look at the BIO_CB_* defines in buffer.h. Argp and argi are the arguments
|
|
passed to BIO_read(), BIO_write, BIO_gets(), BIO_puts(). In the case of
|
|
BIO_ctrl(), argl is also defined. The first time the callback is called,
|
|
before the underlying function has been executed, 0 is passed as 'ret', and
|
|
if the return code from the callback is not > 0, the call is aborted
|
|
and the returned <= 0 value is returned.
|
|
The second time the callback is called, the 'cmd' value also has
|
|
BIO_CB_RETURN logically 'or'ed with it. The 'ret' value is the value returned
|
|
from the actuall function call and whatever the callback returns is returned
|
|
from the BIO function.
|
|
|
|
BIO_set_callback(b,cb) can be used to set the callback function
|
|
(b is a BIO), and BIO_set_callback_arg(b,arg) can be used to
|
|
set the cb_arg argument in the BIO strucutre. This field is only intended
|
|
to be used by application, primarily in the callback function since it is
|
|
accessable since the BIO is passed.
|
|
|
|
--------------------------
|
|
The PEM library.
|
|
|
|
The pem library only really uses one type of callback,
|
|
static int def_callback(char *buf, int num, int verify);
|
|
which is used to return a password string if required.
|
|
'buf' is the buffer to put the string in. 'num' is the size of 'buf'
|
|
and 'verify' is used to indicate that the password should be checked.
|
|
This last flag is mostly used when reading a password for encryption.
|
|
|
|
For all of these functions, a NULL callback will call the above mentioned
|
|
default callback. This default function does not work under Windows 3.1.
|
|
For other machines, it will use an application defined prompt string
|
|
(EVP_set_pw_prompt(), which defines a library wide prompt string)
|
|
if defined, otherwise it will use it's own PEM password prompt.
|
|
It will then call EVP_read_pw_string() to get a password from the console.
|
|
If your application wishes to use nice fancy windows to retrieve passwords,
|
|
replace this function. The callback should return the number of bytes read
|
|
into 'buf'. If the number of bytes <= 0, it is considered an error.
|
|
|
|
Functions that take this callback are listed below. For the 'read' type
|
|
functions, the callback will only be required if the PEM data is encrypted.
|
|
|
|
For the Write functions, normally a password can be passed in 'kstr', of
|
|
'klen' bytes which will be used if the 'enc' cipher is not NULL. If
|
|
'kstr' is NULL, the callback will be used to retrieve a password.
|
|
|
|
int PEM_do_header (EVP_CIPHER_INFO *cipher, unsigned char *data,long *len,
|
|
int (*callback)());
|
|
char *PEM_ASN1_read_bio(char *(*d2i)(),char *name,BIO *bp,char **x,int (*cb)());
|
|
char *PEM_ASN1_read(char *(*d2i)(),char *name,FILE *fp,char **x,int (*cb)());
|
|
int PEM_ASN1_write_bio(int (*i2d)(),char *name,BIO *bp,char *x,
|
|
EVP_CIPHER *enc,unsigned char *kstr,int klen,int (*callback)());
|
|
int PEM_ASN1_write(int (*i2d)(),char *name,FILE *fp,char *x,
|
|
EVP_CIPHER *enc,unsigned char *kstr,int klen,int (*callback)());
|
|
STACK *PEM_X509_INFO_read(FILE *fp, STACK *sk, int (*cb)());
|
|
STACK *PEM_X509_INFO_read_bio(BIO *fp, STACK *sk, int (*cb)());
|
|
|
|
#define PEM_write_RSAPrivateKey(fp,x,enc,kstr,klen,cb)
|
|
#define PEM_write_DSAPrivateKey(fp,x,enc,kstr,klen,cb)
|
|
#define PEM_write_bio_RSAPrivateKey(bp,x,enc,kstr,klen,cb)
|
|
#define PEM_write_bio_DSAPrivateKey(bp,x,enc,kstr,klen,cb)
|
|
#define PEM_read_SSL_SESSION(fp,x,cb)
|
|
#define PEM_read_X509(fp,x,cb)
|
|
#define PEM_read_X509_REQ(fp,x,cb)
|
|
#define PEM_read_X509_CRL(fp,x,cb)
|
|
#define PEM_read_RSAPrivateKey(fp,x,cb)
|
|
#define PEM_read_DSAPrivateKey(fp,x,cb)
|
|
#define PEM_read_PrivateKey(fp,x,cb)
|
|
#define PEM_read_PKCS7(fp,x,cb)
|
|
#define PEM_read_DHparams(fp,x,cb)
|
|
#define PEM_read_bio_SSL_SESSION(bp,x,cb)
|
|
#define PEM_read_bio_X509(bp,x,cb)
|
|
#define PEM_read_bio_X509_REQ(bp,x,cb)
|
|
#define PEM_read_bio_X509_CRL(bp,x,cb)
|
|
#define PEM_read_bio_RSAPrivateKey(bp,x,cb)
|
|
#define PEM_read_bio_DSAPrivateKey(bp,x,cb)
|
|
#define PEM_read_bio_PrivateKey(bp,x,cb)
|
|
#define PEM_read_bio_PKCS7(bp,x,cb)
|
|
#define PEM_read_bio_DHparams(bp,x,cb)
|
|
int i2d_Netscape_RSA(RSA *a, unsigned char **pp, int (*cb)());
|
|
RSA *d2i_Netscape_RSA(RSA **a, unsigned char **pp, long length, int (*cb)());
|
|
|
|
Now you will notice that macros like
|
|
#define PEM_write_X509(fp,x) \
|
|
PEM_ASN1_write((int (*)())i2d_X509,PEM_STRING_X509,fp, \
|
|
(char *)x, NULL,NULL,0,NULL)
|
|
Don't do encryption normally. If you want to PEM encrypt your X509 structure,
|
|
either just call PEM_ASN1_write directly or just define you own
|
|
macro variant. As you can see, this macro just sets all encryption related
|
|
parameters to NULL.
|
|
|
|
|
|
--------------------------
|
|
The SSL library.
|
|
|
|
#define SSL_set_info_callback(ssl,cb)
|
|
#define SSL_CTX_set_info_callback(ctx,cb)
|
|
void callback(SSL *ssl,int location,int ret)
|
|
This callback is called each time around the SSL_connect()/SSL_accept()
|
|
state machine. So it will be called each time the SSL protocol progresses.
|
|
It is mostly present for use when debugging. When SSL_connect() or
|
|
SSL_accept() return, the location flag is SSL_CB_ACCEPT_EXIT or
|
|
SSL_CB_CONNECT_EXIT and 'ret' is the value about to be returned.
|
|
Have a look at the SSL_CB_* defines in ssl.h. If an info callback is defined
|
|
against the SSL_CTX, it is called unless there is one set against the SSL.
|
|
Have a look at
|
|
void client_info_callback() in apps/s_client() for an example.
|
|
|
|
Certificate verification.
|
|
void SSL_set_verify(SSL *s, int mode, int (*callback) ());
|
|
void SSL_CTX_set_verify(SSL_CTX *ctx,int mode,int (*callback)());
|
|
This callback is used to help verify client and server X509 certificates.
|
|
It is actually passed to X509_cert_verify(), along with the SSL structure
|
|
so you have to read about X509_cert_verify() :-). The SSL_CTX version is used
|
|
if the SSL version is not defined. X509_cert_verify() is the function used
|
|
by the SSL part of the library to verify certificates. This function is
|
|
nearly always defined by the application.
|
|
|
|
void SSL_CTX_set_cert_verify_cb(SSL_CTX *ctx, int (*cb)(),char *arg);
|
|
int callback(char *arg,SSL *s,X509 *xs,STACK *cert_chain);
|
|
This call is used to replace the SSLeay certificate verification code.
|
|
The 'arg' is kept in the SSL_CTX and is passed to the callback.
|
|
If the callback returns 0, the certificate is rejected, otherwise it
|
|
is accepted. The callback is replacing the X509_cert_verify() call.
|
|
This feature is not often used, but if you wished to implement
|
|
some totally different certificate authentication system, this 'hook' is
|
|
vital.
|
|
|
|
SSLeay keeps a cache of session-ids against each SSL_CTX. These callbacks can
|
|
be used to notify the application when a SSL_SESSION is added to the cache
|
|
or to retrieve a SSL_SESSION that is not in the cache from the application.
|
|
#define SSL_CTX_sess_set_get_cb(ctx,cb)
|
|
SSL_SESSION *callback(SSL *s,char *session_id,int session_id_len,int *copy);
|
|
If defined, this callback is called to return the SESSION_ID for the
|
|
session-id in 'session_id', of 'session_id_len' bytes. 'copy' is set to 1
|
|
if the server is to 'take a copy' of the SSL_SESSION structure. It is 0
|
|
if the SSL_SESSION is being 'passed in' so the SSLeay library is now
|
|
responsible for 'free()ing' the structure. Basically it is used to indicate
|
|
if the reference count on the SSL_SESSION structure needs to be incremented.
|
|
|
|
#define SSL_CTX_sess_set_new_cb(ctx,cb)
|
|
int callback(SSL *s, SSL_SESSION *sess);
|
|
When a new connection is established, if the SSL_SESSION is going to be added
|
|
to the cache, this callback is called. Return 1 if a 'copy' is required,
|
|
otherwise, return 0. This return value just causes the reference count
|
|
to be incremented (on return of a 1), this means the application does
|
|
not need to worry about incrementing the refernece count (and the
|
|
locking that implies in a multi-threaded application).
|
|
|
|
void SSL_CTX_set_default_passwd_cb(SSL_CTX *ctx,int (*cb)());
|
|
This sets the SSL password reading function.
|
|
It is mostly used for windowing applications
|
|
and used by PEM_read_bio_X509() and PEM_read_bio_RSAPrivateKey()
|
|
calls inside the SSL library. The only reason this is present is because the
|
|
calls to PEM_* functions is hidden in the SSLeay library so you have to
|
|
pass in the callback some how.
|
|
|
|
#define SSL_CTX_set_client_cert_cb(ctx,cb)
|
|
int callback(SSL *s,X509 **x509, EVP_PKEY **pkey);
|
|
Called when a client certificate is requested but there is not one set
|
|
against the SSL_CTX or the SSL. If the callback returns 1, x509 and
|
|
pkey need to point to valid data. The library will free these when
|
|
required so if the application wants to keep these around, increment
|
|
their reference counts. If 0 is returned, no client cert is
|
|
available. If -1 is returned, it is assumed that the callback needs
|
|
to be called again at a later point in time. SSL_connect will return
|
|
-1 and SSL_want_x509_lookup(ssl) returns true. Remember that
|
|
application data can be attached to an SSL structure via the
|
|
SSL_set_app_data(SSL *ssl,char *data) call.
|
|
|
|
--------------------------
|
|
The X509 library.
|
|
|
|
int X509_cert_verify(CERTIFICATE_CTX *ctx,X509 *xs, int (*cb)(),
|
|
int *error,char *arg,STACK *cert_chain);
|
|
int verify_callback(int ok,X509 *xs,X509 *xi,int depth,int error,char *arg,
|
|
STACK *cert_chain);
|
|
|
|
X509_cert_verify() is used to authenticate X509 certificates. The 'ctx' holds
|
|
the details of the various caches and files used to locate certificates.
|
|
'xs' is the certificate to verify and 'cb' is the application callback (more
|
|
detail later). 'error' will be set to the error code and 'arg' is passed
|
|
to the 'cb' callback. Look at the VERIFY_* defines in crypto/x509/x509.h
|
|
|
|
When ever X509_cert_verify() makes a 'negative' decision about a
|
|
certitificate, the callback is called. If everything checks out, the
|
|
callback is called with 'VERIFY_OK' or 'VERIFY_ROOT_OK' (for a self
|
|
signed cert that is not the passed certificate).
|
|
|
|
The callback is passed the X509_cert_verify opinion of the certificate
|
|
in 'ok', the certificate in 'xs', the issuer certificate in 'xi',
|
|
the 'depth' of the certificate in the verification 'chain', the
|
|
VERIFY_* code in 'error' and the argument passed to X509_cert_verify()
|
|
in 'arg'. cert_chain is a list of extra certs to use if they are not
|
|
in the cache.
|
|
|
|
The callback can be used to look at the error reason, and then return 0
|
|
for an 'error' or '1' for ok. This will override the X509_cert_verify()
|
|
opinion of the certificates validity. Processing will continue depending on
|
|
the return value. If one just wishes to use the callback for informational
|
|
reason, just return the 'ok' parameter.
|
|
|
|
--------------------------
|
|
The BN and DH library.
|
|
|
|
BIGNUM *BN_generate_prime(int bits,int strong,BIGNUM *add,
|
|
BIGNUM *rem,void (*callback)(int,int));
|
|
int BN_is_prime(BIGNUM *p,int nchecks,void (*callback)(int,int),
|
|
|
|
Read doc/bn.doc for the description of these 2.
|
|
|
|
DH *DH_generate_parameters(int prime_len,int generator,
|
|
void (*callback)(int,int));
|
|
Read doc/bn.doc for the description of the callback, since it is just passed
|
|
to BN_generate_prime(), except that it is also called as
|
|
callback(3,0) by this function.
|
|
|
|
--------------------------
|
|
The CRYPTO library.
|
|
|
|
void CRYPTO_set_locking_callback(void (*func)(int mode,int type,char *file,
|
|
int line));
|
|
void CRYPTO_set_add_lock_callback(int (*func)(int *num,int mount,
|
|
int type,char *file, int line));
|
|
void CRYPTO_set_id_callback(unsigned long (*func)(void));
|
|
|
|
Read threads.doc for info on these ones.
|
|
|
|
|
|
==== cipher.doc ========================================================
|
|
|
|
The Cipher subroutines.
|
|
|
|
These routines require "evp.h" to be included.
|
|
|
|
These functions are a higher level interface to the various cipher
|
|
routines found in this library. As such, they allow the same code to be
|
|
used to encrypt and decrypt via different ciphers with only a change
|
|
in an initial parameter. These routines also provide buffering for block
|
|
ciphers.
|
|
|
|
These routines all take a pointer to the following structure to specify
|
|
which cipher to use. If you wish to use a new cipher with these routines,
|
|
you would probably be best off looking an how an existing cipher is
|
|
implemented and copying it. At this point in time, I'm not going to go
|
|
into many details. This structure should be considered opaque
|
|
|
|
typedef struct pem_cipher_st
|
|
{
|
|
int type;
|
|
int block_size;
|
|
int key_len;
|
|
int iv_len;
|
|
void (*enc_init)(); /* init for encryption */
|
|
void (*dec_init)(); /* init for decryption */
|
|
void (*do_cipher)(); /* encrypt data */
|
|
} EVP_CIPHER;
|
|
|
|
The type field is the object NID of the cipher type
|
|
(read the section on Objects for an explanation of what a NID is).
|
|
The cipher block_size is how many bytes need to be passed
|
|
to the cipher at a time. Key_len is the
|
|
length of the key the cipher requires and iv_len is the length of the
|
|
initialisation vector required. enc_init is the function
|
|
called to initialise the ciphers context for encryption and dec_init is the
|
|
function to initialise for decryption (they need to be different, especially
|
|
for the IDEA cipher).
|
|
|
|
One reason for specifying the Cipher via a pointer to a structure
|
|
is that if you only use des-cbc, only the des-cbc routines will
|
|
be included when you link the program. If you passed an integer
|
|
that specified which cipher to use, the routine that mapped that
|
|
integer to a set of cipher functions would cause all the ciphers
|
|
to be link into the code. This setup also allows new ciphers
|
|
to be added by the application (with some restrictions).
|
|
|
|
The thirteen ciphers currently defined in this library are
|
|
|
|
EVP_CIPHER *EVP_des_ecb(); /* DES in ecb mode, iv=0, block=8, key= 8 */
|
|
EVP_CIPHER *EVP_des_ede(); /* DES in ecb ede mode, iv=0, block=8, key=16 */
|
|
EVP_CIPHER *EVP_des_ede3(); /* DES in ecb ede mode, iv=0, block=8, key=24 */
|
|
EVP_CIPHER *EVP_des_cfb(); /* DES in cfb mode, iv=8, block=1, key= 8 */
|
|
EVP_CIPHER *EVP_des_ede_cfb(); /* DES in ede cfb mode, iv=8, block=1, key=16 */
|
|
EVP_CIPHER *EVP_des_ede3_cfb();/* DES in ede cfb mode, iv=8, block=1, key=24 */
|
|
EVP_CIPHER *EVP_des_ofb(); /* DES in ofb mode, iv=8, block=1, key= 8 */
|
|
EVP_CIPHER *EVP_des_ede_ofb(); /* DES in ede ofb mode, iv=8, block=1, key=16 */
|
|
EVP_CIPHER *EVP_des_ede3_ofb();/* DES in ede ofb mode, iv=8, block=1, key=24 */
|
|
EVP_CIPHER *EVP_des_cbc(); /* DES in cbc mode, iv=8, block=8, key= 8 */
|
|
EVP_CIPHER *EVP_des_ede_cbc(); /* DES in cbc ede mode, iv=8, block=8, key=16 */
|
|
EVP_CIPHER *EVP_des_ede3_cbc();/* DES in cbc ede mode, iv=8, block=8, key=24 */
|
|
EVP_CIPHER *EVP_desx_cbc(); /* DES in desx cbc mode,iv=8, block=8, key=24 */
|
|
EVP_CIPHER *EVP_rc4(); /* RC4, iv=0, block=1, key=16 */
|
|
EVP_CIPHER *EVP_idea_ecb(); /* IDEA in ecb mode, iv=0, block=8, key=16 */
|
|
EVP_CIPHER *EVP_idea_cfb(); /* IDEA in cfb mode, iv=8, block=1, key=16 */
|
|
EVP_CIPHER *EVP_idea_ofb(); /* IDEA in ofb mode, iv=8, block=1, key=16 */
|
|
EVP_CIPHER *EVP_idea_cbc(); /* IDEA in cbc mode, iv=8, block=8, key=16 */
|
|
EVP_CIPHER *EVP_rc2_ecb(); /* RC2 in ecb mode, iv=0, block=8, key=16 */
|
|
EVP_CIPHER *EVP_rc2_cfb(); /* RC2 in cfb mode, iv=8, block=1, key=16 */
|
|
EVP_CIPHER *EVP_rc2_ofb(); /* RC2 in ofb mode, iv=8, block=1, key=16 */
|
|
EVP_CIPHER *EVP_rc2_cbc(); /* RC2 in cbc mode, iv=8, block=8, key=16 */
|
|
EVP_CIPHER *EVP_bf_ecb(); /* Blowfish in ecb mode,iv=0, block=8, key=16 */
|
|
EVP_CIPHER *EVP_bf_cfb(); /* Blowfish in cfb mode,iv=8, block=1, key=16 */
|
|
EVP_CIPHER *EVP_bf_ofb(); /* Blowfish in ofb mode,iv=8, block=1, key=16 */
|
|
EVP_CIPHER *EVP_bf_cbc(); /* Blowfish in cbc mode,iv=8, block=8, key=16 */
|
|
|
|
The meaning of the compound names is as follows.
|
|
des The base cipher is DES.
|
|
idea The base cipher is IDEA
|
|
rc4 The base cipher is RC4-128
|
|
rc2 The base cipher is RC2-128
|
|
ecb Electronic Code Book form of the cipher.
|
|
cbc Cipher Block Chaining form of the cipher.
|
|
cfb 64 bit Cipher Feedback form of the cipher.
|
|
ofb 64 bit Output Feedback form of the cipher.
|
|
ede The cipher is used in Encrypt, Decrypt, Encrypt mode. The first
|
|
and last keys are the same.
|
|
ede3 The cipher is used in Encrypt, Decrypt, Encrypt mode.
|
|
|
|
All the Cipher routines take a EVP_CIPHER_CTX pointer as an argument.
|
|
The state of the cipher is kept in this structure.
|
|
|
|
typedef struct EVP_CIPHER_Ctx_st
|
|
{
|
|
EVP_CIPHER *cipher;
|
|
int encrypt; /* encrypt or decrypt */
|
|
int buf_len; /* number we have left */
|
|
unsigned char buf[8];
|
|
union {
|
|
.... /* cipher specific stuff */
|
|
} c;
|
|
} EVP_CIPHER_CTX;
|
|
|
|
Cipher is a pointer the the EVP_CIPHER for the current context. The encrypt
|
|
flag indicates encryption or decryption. buf_len is the number of bytes
|
|
currently being held in buf.
|
|
The 'c' union holds the cipher specify context.
|
|
|
|
The following functions are to be used.
|
|
|
|
int EVP_read_pw_string(
|
|
char *buf,
|
|
int len,
|
|
char *prompt,
|
|
int verify,
|
|
This function is the same as des_read_pw_string() (des.doc).
|
|
|
|
void EVP_set_pw_prompt(char *prompt);
|
|
This function sets the 'default' prompt to use to use in
|
|
EVP_read_pw_string when the prompt parameter is NULL. If the
|
|
prompt parameter is NULL, this 'default prompt' feature is turned
|
|
off. Be warned, this is a global variable so weird things
|
|
will happen if it is used under Win16 and care must be taken
|
|
with a multi-threaded version of the library.
|
|
|
|
char *EVP_get_pw_prompt();
|
|
This returns a pointer to the default prompt string. NULL
|
|
if it is not set.
|
|
|
|
int EVP_BytesToKey(
|
|
EVP_CIPHER *type,
|
|
EVP_MD *md,
|
|
unsigned char *salt,
|
|
unsigned char *data,
|
|
int datal,
|
|
int count,
|
|
unsigned char *key,
|
|
unsigned char *iv);
|
|
This function is used to generate a key and an initialisation vector
|
|
for a specified cipher from a key string and a salt. Type
|
|
specifies the cipher the 'key' is being generated for. Md is the
|
|
message digest algorithm to use to generate the key and iv. The salt
|
|
is an optional 8 byte object that is used to help seed the key
|
|
generator.
|
|
If the salt value is NULL, it is just not used. Datal is the
|
|
number of bytes to use from 'data' in the key generation.
|
|
This function returns the key size for the specified cipher, if
|
|
data is NULL, this value is returns and no other
|
|
computation is performed. Count is
|
|
the number of times to loop around the key generator. I would
|
|
suggest leaving it's value as 1. Key and iv are the structures to
|
|
place the returning iv and key in. If they are NULL, no value is
|
|
generated for that particular value.
|
|
The algorithm used is as follows
|
|
|
|
/* M[] is an array of message digests
|
|
* MD() is the message digest function */
|
|
M[0]=MD(data . salt);
|
|
for (i=1; i<count; i++) M[0]=MD(M[0]);
|
|
|
|
i=1
|
|
while (data still needed for key and iv)
|
|
{
|
|
M[i]=MD(M[i-1] . data . salt);
|
|
for (i=1; i<count; i++) M[i]=MD(M[i]);
|
|
i++;
|
|
}
|
|
|
|
If the salt is NULL, it is not used.
|
|
The digests are concatenated together.
|
|
M = M[0] . M[1] . M[2] .......
|
|
|
|
For key= 8, iv=8 => key=M[0.. 8], iv=M[ 9 .. 16].
|
|
For key=16, iv=0 => key=M[0..16].
|
|
For key=16, iv=8 => key=M[0..16], iv=M[17 .. 24].
|
|
For key=24, iv=8 => key=M[0..24], iv=M[25 .. 32].
|
|
|
|
This routine will produce DES-CBC keys and iv that are compatible
|
|
with the PKCS-5 standard when md2 or md5 are used. If md5 is
|
|
used, the salt is NULL and count is 1, this routine will produce
|
|
the password to key mapping normally used with RC4.
|
|
I have attempted to logically extend the PKCS-5 standard to
|
|
generate keys and iv for ciphers that require more than 16 bytes,
|
|
if anyone knows what the correct standard is, please inform me.
|
|
When using sha or sha1, things are a bit different under this scheme,
|
|
since sha produces a 20 byte digest. So for ciphers requiring
|
|
24 bits of data, 20 will come from the first MD and 4 will
|
|
come from the second.
|
|
|
|
I have considered having a separate function so this 'routine'
|
|
can be used without the requirement of passing a EVP_CIPHER *,
|
|
but I have decided to not bother. If you wish to use the
|
|
function without official EVP_CIPHER structures, just declare
|
|
a local one and set the key_len and iv_len fields to the
|
|
length you desire.
|
|
|
|
The following routines perform encryption and decryption 'by parts'. By
|
|
this I mean that there are groups of 3 routines. An Init function that is
|
|
used to specify a cipher and initialise data structures. An Update routine
|
|
that does encryption/decryption, one 'chunk' at a time. And finally a
|
|
'Final' function that finishes the encryption/decryption process.
|
|
All these functions take a EVP_CIPHER pointer to specify which cipher to
|
|
encrypt/decrypt with. They also take a EVP_CIPHER_CTX object as an
|
|
argument. This structure is used to hold the state information associated
|
|
with the operation in progress.
|
|
|
|
void EVP_EncryptInit(
|
|
EVP_CIPHER_CTX *ctx,
|
|
EVP_CIPHER *type,
|
|
unsigned char *key,
|
|
unsigned char *iv);
|
|
This function initialise a EVP_CIPHER_CTX for encryption using the
|
|
cipher passed in the 'type' field. The cipher is initialised to use
|
|
'key' as the key and 'iv' for the initialisation vector (if one is
|
|
required). If the type, key or iv is NULL, the value currently in the
|
|
EVP_CIPHER_CTX is reused. So to perform several decrypt
|
|
using the same cipher, key and iv, initialise with the cipher,
|
|
key and iv the first time and then for subsequent calls,
|
|
reuse 'ctx' but pass NULL for type, key and iv. You must make sure
|
|
to pass a key that is large enough for a particular cipher. I
|
|
would suggest using the EVP_BytesToKey() function.
|
|
|
|
void EVP_EncryptUpdate(
|
|
EVP_CIPHER_CTX *ctx,
|
|
unsigned char *out,
|
|
int *outl,
|
|
unsigned char *in,
|
|
int inl);
|
|
This function takes 'inl' bytes from 'in' and outputs bytes
|
|
encrypted by the cipher 'ctx' was initialised with into 'out'. The
|
|
number of bytes written to 'out' is put into outl. If a particular
|
|
cipher encrypts in blocks, less or more bytes than input may be
|
|
output. Currently the largest block size used by supported ciphers
|
|
is 8 bytes, so 'out' should have room for 'inl+7' bytes. Normally
|
|
EVP_EncryptInit() is called once, followed by lots and lots of
|
|
calls to EVP_EncryptUpdate, followed by a single EVP_EncryptFinal
|
|
call.
|
|
|
|
void EVP_EncryptFinal(
|
|
EVP_CIPHER_CTX *ctx,
|
|
unsigned char *out,
|
|
int *outl);
|
|
Because quite a large number of ciphers are block ciphers, there is
|
|
often an incomplete block to write out at the end of the
|
|
encryption. EVP_EncryptFinal() performs processing on this last
|
|
block. The last block in encoded in such a way that it is possible
|
|
to determine how many bytes in the last block are valid. For 8 byte
|
|
block size ciphers, if only 5 bytes in the last block are valid, the
|
|
last three bytes will be filled with the value 3. If only 2 were
|
|
valid, the other 6 would be filled with sixes. If all 8 bytes are
|
|
valid, a extra 8 bytes are appended to the cipher stream containing
|
|
nothing but 8 eights. These last bytes are output into 'out' and
|
|
the number of bytes written is put into 'outl' These last bytes
|
|
are output into 'out' and the number of bytes written is put into
|
|
'outl'. This form of block cipher finalisation is compatible with
|
|
PKCS-5. Please remember that even if you are using ciphers like
|
|
RC4 that has no blocking and so the function will not write
|
|
anything into 'out', it would still be a good idea to pass a
|
|
variable for 'out' that can hold 8 bytes just in case the cipher is
|
|
changed some time in the future. It should also be remembered
|
|
that the EVP_CIPHER_CTX contains the password and so when one has
|
|
finished encryption with a particular EVP_CIPHER_CTX, it is good
|
|
practice to zero the structure
|
|
(ie. memset(ctx,0,sizeof(EVP_CIPHER_CTX)).
|
|
|
|
void EVP_DecryptInit(
|
|
EVP_CIPHER_CTX *ctx,
|
|
EVP_CIPHER *type,
|
|
unsigned char *key,
|
|
unsigned char *iv);
|
|
This function is basically the same as EVP_EncryptInit() accept that
|
|
is prepares the EVP_CIPHER_CTX for decryption.
|
|
|
|
void EVP_DecryptUpdate(
|
|
EVP_CIPHER_CTX *ctx,
|
|
unsigned char *out,
|
|
int *outl,
|
|
unsigned char *in,
|
|
int inl);
|
|
This function is basically the same as EVP_EncryptUpdate()
|
|
except that it performs decryption. There is one
|
|
fundamental difference though. 'out' can not be the same as
|
|
'in' for any ciphers with a block size greater than 1 if more
|
|
than one call to EVP_DecryptUpdate() will be made. This
|
|
is because this routine can hold a 'partial' block between
|
|
calls. When a partial block is decrypted (due to more bytes
|
|
being passed via this function, they will be written to 'out'
|
|
overwriting the input bytes in 'in' that have not been read
|
|
yet. From this it should also be noted that 'out' should
|
|
be at least one 'block size' larger than 'inl'. This problem
|
|
only occurs on the second and subsequent call to
|
|
EVP_DecryptUpdate() when using a block cipher.
|
|
|
|
int EVP_DecryptFinal(
|
|
EVP_CIPHER_CTX *ctx,
|
|
unsigned char *out,
|
|
int *outl);
|
|
This function is different to EVP_EncryptFinal in that it 'removes'
|
|
any padding bytes appended when the data was encrypted. Due to the
|
|
way in which 1 to 8 bytes may have been appended when encryption
|
|
using a block cipher, 'out' can end up with 0 to 7 bytes being put
|
|
into it. When decoding the padding bytes, it is possible to detect
|
|
an incorrect decryption. If the decryption appears to be wrong, 0
|
|
is returned. If everything seems ok, 1 is returned. For ciphers
|
|
with a block size of 1 (RC4), this function would normally not
|
|
return any bytes and would always return 1. Just because this
|
|
function returns 1 does not mean the decryption was correct. It
|
|
would normally be wrong due to either the wrong key/iv or
|
|
corruption of the cipher data fed to EVP_DecryptUpdate().
|
|
As for EVP_EncryptFinal, it is a good idea to zero the
|
|
EVP_CIPHER_CTX after use since the structure contains the key used
|
|
to decrypt the data.
|
|
|
|
The following Cipher routines are convenience routines that call either
|
|
EVP_EncryptXxx or EVP_DecryptXxx depending on weather the EVP_CIPHER_CTX
|
|
was setup to encrypt or decrypt.
|
|
|
|
void EVP_CipherInit(
|
|
EVP_CIPHER_CTX *ctx,
|
|
EVP_CIPHER *type,
|
|
unsigned char *key,
|
|
unsigned char *iv,
|
|
int enc);
|
|
This function take arguments that are the same as EVP_EncryptInit()
|
|
and EVP_DecryptInit() except for the extra 'enc' flag. If 1, the
|
|
EVP_CIPHER_CTX is setup for encryption, if 0, decryption.
|
|
|
|
void EVP_CipherUpdate(
|
|
EVP_CIPHER_CTX *ctx,
|
|
unsigned char *out,
|
|
int *outl,
|
|
unsigned char *in,
|
|
int inl);
|
|
Again this function calls either EVP_EncryptUpdate() or
|
|
EVP_DecryptUpdate() depending on state in the 'ctx' structure.
|
|
As noted for EVP_DecryptUpdate(), when this routine is used
|
|
for decryption with block ciphers, 'out' should not be the
|
|
same as 'in'.
|
|
|
|
int EVP_CipherFinal(
|
|
EVP_CIPHER_CTX *ctx,
|
|
unsigned char *outm,
|
|
int *outl);
|
|
This routine call EVP_EncryptFinal() or EVP_DecryptFinal()
|
|
depending on the state information in 'ctx'. 1 is always returned
|
|
if the mode is encryption, otherwise the return value is the return
|
|
value of EVP_DecryptFinal().
|
|
|
|
==== cipher.m ========================================================
|
|
|
|
Date: Tue, 15 Oct 1996 08:16:14 +1000 (EST)
|
|
From: Eric Young <eay@mincom.com>
|
|
X-Sender: eay@orb
|
|
To: Roland Haring <rharing@tandem.cl>
|
|
Cc: ssl-users@mincom.com
|
|
Subject: Re: Symmetric encryption with ssleay
|
|
In-Reply-To: <m0vBpyq-00001aC@tandemnet.tandem.cl>
|
|
Message-Id: <Pine.SOL.3.91.961015075623.11394A-100000@orb>
|
|
Mime-Version: 1.0
|
|
Content-Type: TEXT/PLAIN; charset=US-ASCII
|
|
Sender: ssl-lists-owner@mincom.com
|
|
Precedence: bulk
|
|
Status: RO
|
|
X-Status:
|
|
|
|
On Fri, 11 Oct 1996, Roland Haring wrote:
|
|
> THE_POINT:
|
|
> Would somebody be so kind to give me the minimum basic
|
|
> calls I need to do to libcrypto.a to get some text encrypted
|
|
> and decrypted again? ...hopefully with code included to do
|
|
> base64 encryption and decryption ... e.g. that sign-it.c code
|
|
> posted some while ago was a big help :-) (please, do not point
|
|
> me to apps/enc.c where I suspect my Heissenbug to be hidden :-)
|
|
|
|
Ok, the base64 encoding stuff in 'enc.c' does the wrong thing sometimes
|
|
when the data is less than a line long (this is for decoding). I'll dig
|
|
up the exact fix today and post it. I am taking longer on 0.6.5 than I
|
|
intended so I'll just post this patch.
|
|
|
|
The documentation to read is in
|
|
doc/cipher.doc,
|
|
doc/encode.doc (very sparse :-).
|
|
and perhaps
|
|
doc/digest.doc,
|
|
|
|
The basic calls to encrypt with say triple DES are
|
|
|
|
Given
|
|
char key[EVP_MAX_KEY_LENGTH];
|
|
char iv[EVP_MAX_IV_LENGTH];
|
|
EVP_CIPHER_CTX ctx;
|
|
unsigned char out[512+8];
|
|
int outl;
|
|
|
|
/* optional generation of key/iv data from text password using md5
|
|
* via an upward compatable verson of PKCS#5. */
|
|
EVP_BytesToKey(EVP_des_ede3_cbc,EVP_md5,NULL,passwd,strlen(passwd),
|
|
key,iv);
|
|
|
|
/* Initalise the EVP_CIPHER_CTX */
|
|
EVP_EncryptInit(ctx,EVP_des_ede3_cbc,key,iv);
|
|
|
|
while (....)
|
|
{
|
|
/* This is processing 512 bytes at a time, the bytes are being
|
|
* copied into 'out', outl bytes are output. 'out' should not be the
|
|
* same as 'in' for reasons mentioned in the documentation. */
|
|
EVP_EncryptUpdate(ctx,out,&outl,in,512);
|
|
}
|
|
|
|
/* Output the last 'block'. If the cipher is a block cipher, the last
|
|
* block is encoded in such a way so that a wrong decryption will normally be
|
|
* detected - again, one of the PKCS standards. */
|
|
|
|
EVP_EncryptFinal(ctx,out,&outl);
|
|
|
|
To decrypt, use the EVP_DecryptXXXXX functions except that EVP_DecryptFinal()
|
|
will return 0 if the decryption fails (only detectable on block ciphers).
|
|
|
|
You can also use
|
|
EVP_CipherInit()
|
|
EVP_CipherUpdate()
|
|
EVP_CipherFinal()
|
|
which does either encryption or decryption depending on an extra
|
|
parameter to EVP_CipherInit().
|
|
|
|
|
|
To do the base64 encoding,
|
|
EVP_EncodeInit()
|
|
EVP_EncodeUpdate()
|
|
EVP_EncodeFinal()
|
|
|
|
EVP_DecodeInit()
|
|
EVP_DecodeUpdate()
|
|
EVP_DecodeFinal()
|
|
|
|
where the encoding is quite simple, but the decoding can be a bit more
|
|
fun (due to dud input).
|
|
|
|
EVP_DecodeUpdate() returns -1 for an error on an input line, 0 if the
|
|
'last line' was just processed, and 1 if more lines should be submitted.
|
|
|
|
EVP_DecodeFinal() returns -1 for an error or 1 if things are ok.
|
|
|
|
So the loop becomes
|
|
EVP_DecodeInit(....)
|
|
for (;;)
|
|
{
|
|
i=EVP_DecodeUpdate(....);
|
|
if (i < 0) goto err;
|
|
|
|
/* process the data */
|
|
|
|
if (i == 0) break;
|
|
}
|
|
EVP_DecodeFinal(....);
|
|
/* process the data */
|
|
|
|
The problem in 'enc.c' is that I was stuff the processing up after the
|
|
EVP_DecodeFinal(...) when the for(..) loop was not being run (one line of
|
|
base64 data) and this was because 'enc.c' tries to scan over a file until
|
|
it hits the first valid base64 encoded line.
|
|
|
|
hope this helps a bit.
|
|
eric
|
|
--
|
|
Eric Young | BOOL is tri-state according to Bill Gates.
|
|
AARNet: eay@mincom.oz.au | RTFM Win32 GetMessage().
|
|
|
|
==== conf.doc ========================================================
|
|
|
|
The CONF library.
|
|
|
|
The CONF library is a simple set of routines that can be used to configure
|
|
programs. It is a superset of the genenv() function with some extra
|
|
structure.
|
|
|
|
The library consists of 5 functions.
|
|
|
|
LHASH *CONF_load(LHASH *config,char *file);
|
|
This function is called to load in a configuration file. Multiple
|
|
configuration files can be loaded, with each subsequent 'load' overwriting
|
|
any already defined 'variables'. If there is an error, NULL is returned.
|
|
If config is NULL, a new LHASH structure is created and returned, otherwise
|
|
the new data in the 'file' is loaded into the 'config' structure.
|
|
|
|
void CONF_free(LHASH *config);
|
|
This function free()s the data in config.
|
|
|
|
char *CONF_get_string(LHASH *config,char *section,char *name);
|
|
This function returns the string found in 'config' that corresponds to the
|
|
'section' and 'name' specified. Classes and the naming system used will be
|
|
discussed later in this document. If the variable is not defined, an NULL
|
|
is returned.
|
|
|
|
long CONF_get_long(LHASH *config,char *section, char *name);
|
|
This function is the same as CONF_get_string() except that it converts the
|
|
string to an long and returns it. If variable is not a number or the
|
|
variable does not exist, 0 is returned. This is a little problematic but I
|
|
don't know of a simple way around it.
|
|
|
|
STACK *CONF_get_section(LHASH *config, char *section);
|
|
This function returns a 'stack' of CONF_VALUE items that are all the
|
|
items defined in a particular section. DO NOT free() any of the
|
|
variable returned. They will disappear when CONF_free() is called.
|
|
|
|
The 'lookup' model.
|
|
The configuration file is divided into 'sections'. Each section is started by
|
|
a line of the form '[ section ]'. All subsequent variable definitions are
|
|
of this section. A variable definition is a simple alpha-numeric name
|
|
followed by an '=' and then the data. A section or variable name can be
|
|
described by a regular expression of the following form '[A-Za-z0-9_]+'.
|
|
The value of the variable is the text after the '=' until the end of the
|
|
line, stripped of leading and trailing white space.
|
|
At this point I should mention that a '#' is a comment character, \ is the
|
|
escape character, and all three types of quote can be used to stop any
|
|
special interpretation of the data.
|
|
Now when the data is being loaded, variable expansion can occur. This is
|
|
done by expanding any $NAME sequences into the value represented by the
|
|
variable NAME. If the variable is not in the current section, the different
|
|
section can be specified by using the $SECTION::NAME form. The ${NAME} form
|
|
also works and is very useful for expanding variables inside strings.
|
|
|
|
When a variable is looked up, there are 2 special section. 'default', which
|
|
is the initial section, and 'ENV' which is the processes environment
|
|
variables (accessed via getenv()). When a variable is looked up, it is
|
|
first 'matched' with it's section (if one was specified), if this fails, the
|
|
'default' section is matched.
|
|
If the 'lhash' variable passed was NULL, the environment is searched.
|
|
|
|
Now why do we bother with sections? So we can have multiple programs using
|
|
the same configuration file, or multiple instances of the same program
|
|
using different variables. It also provides a nice mechanism to override
|
|
the processes environment variables (eg ENV::HOME=/tmp). If there is a
|
|
program specific variable missing, we can have default values.
|
|
Multiple configuration files can be loaded, with each new value clearing
|
|
any predefined values. A system config file can provide 'default' values,
|
|
and application/usr specific files can provide overriding values.
|
|
|
|
Examples
|
|
|
|
# This is a simple example
|
|
SSLEAY_HOME = /usr/local/ssl
|
|
ENV::PATH = $SSLEAY_HOME/bin:$PATH # override my path
|
|
|
|
[X509]
|
|
cert_dir = $SSLEAY_HOME/certs # /usr/local/ssl/certs
|
|
|
|
[SSL]
|
|
CIPHER = DES-EDE-MD5:RC4-MD5
|
|
USER_CERT = $HOME/${USER}di'r 5' # /home/eay/eaydir 5
|
|
USER_CERT = $HOME/\${USER}di\'r # /home/eay/${USER}di'r
|
|
USER_CERT = "$HOME/${US"ER}di\'r # $HOME/${USER}di'r
|
|
|
|
TEST = 1234\
|
|
5678\
|
|
9ab # TEST=123456789ab
|
|
TTT = 1234\n\n # TTT=1234<nl><nl>
|
|
|
|
|
|
|
|
==== des.doc ========================================================
|
|
|
|
The DES library.
|
|
|
|
Please note that this library was originally written to operate with
|
|
eBones, a version of Kerberos that had had encryption removed when it left
|
|
the USA and then put back in. As such there are some routines that I will
|
|
advise not using but they are still in the library for historical reasons.
|
|
For all calls that have an 'input' and 'output' variables, they can be the
|
|
same.
|
|
|
|
This library requires the inclusion of 'des.h'.
|
|
|
|
All of the encryption functions take what is called a des_key_schedule as an
|
|
argument. A des_key_schedule is an expanded form of the des key.
|
|
A des_key is 8 bytes of odd parity, the type used to hold the key is a
|
|
des_cblock. A des_cblock is an array of 8 bytes, often in this library
|
|
description I will refer to input bytes when the function specifies
|
|
des_cblock's as input or output, this just means that the variable should
|
|
be a multiple of 8 bytes.
|
|
|
|
The define DES_ENCRYPT is passed to specify encryption, DES_DECRYPT to
|
|
specify decryption. The functions and global variable are as follows:
|
|
|
|
int des_check_key;
|
|
DES keys are supposed to be odd parity. If this variable is set to
|
|
a non-zero value, des_set_key() will check that the key has odd
|
|
parity and is not one of the known weak DES keys. By default this
|
|
variable is turned off;
|
|
|
|
void des_set_odd_parity(
|
|
des_cblock *key );
|
|
This function takes a DES key (8 bytes) and sets the parity to odd.
|
|
|
|
int des_is_weak_key(
|
|
des_cblock *key );
|
|
This function returns a non-zero value if the DES key passed is a
|
|
weak, DES key. If it is a weak key, don't use it, try a different
|
|
one. If you are using 'random' keys, the chances of hitting a weak
|
|
key are 1/2^52 so it is probably not worth checking for them.
|
|
|
|
int des_set_key(
|
|
des_cblock *key,
|
|
des_key_schedule schedule);
|
|
Des_set_key converts an 8 byte DES key into a des_key_schedule.
|
|
A des_key_schedule is an expanded form of the key which is used to
|
|
perform actual encryption. It can be regenerated from the DES key
|
|
so it only needs to be kept when encryption or decryption is about
|
|
to occur. Don't save or pass around des_key_schedule's since they
|
|
are CPU architecture dependent, DES keys are not. If des_check_key
|
|
is non zero, zero is returned if the key has the wrong parity or
|
|
the key is a weak key, else 1 is returned.
|
|
|
|
int des_key_sched(
|
|
des_cblock *key,
|
|
des_key_schedule schedule);
|
|
An alternative name for des_set_key().
|
|
|
|
int des_rw_mode; /* defaults to DES_PCBC_MODE */
|
|
This flag holds either DES_CBC_MODE or DES_PCBC_MODE (default).
|
|
This specifies the function to use in the enc_read() and enc_write()
|
|
functions.
|
|
|
|
void des_encrypt(
|
|
unsigned long *data,
|
|
des_key_schedule ks,
|
|
int enc);
|
|
This is the DES encryption function that gets called by just about
|
|
every other DES routine in the library. You should not use this
|
|
function except to implement 'modes' of DES. I say this because the
|
|
functions that call this routine do the conversion from 'char *' to
|
|
long, and this needs to be done to make sure 'non-aligned' memory
|
|
access do not occur. The characters are loaded 'little endian',
|
|
have a look at my source code for more details on how I use this
|
|
function.
|
|
Data is a pointer to 2 unsigned long's and ks is the
|
|
des_key_schedule to use. enc, is non zero specifies encryption,
|
|
zero if decryption.
|
|
|
|
void des_encrypt2(
|
|
unsigned long *data,
|
|
des_key_schedule ks,
|
|
int enc);
|
|
This functions is the same as des_encrypt() except that the DES
|
|
initial permutation (IP) and final permutation (FP) have been left
|
|
out. As for des_encrypt(), you should not use this function.
|
|
It is used by the routines in my library that implement triple DES.
|
|
IP() des_encrypt2() des_encrypt2() des_encrypt2() FP() is the same
|
|
as des_encrypt() des_encrypt() des_encrypt() except faster :-).
|
|
|
|
void des_ecb_encrypt(
|
|
des_cblock *input,
|
|
des_cblock *output,
|
|
des_key_schedule ks,
|
|
int enc);
|
|
This is the basic Electronic Code Book form of DES, the most basic
|
|
form. Input is encrypted into output using the key represented by
|
|
ks. If enc is non zero (DES_ENCRYPT), encryption occurs, otherwise
|
|
decryption occurs. Input is 8 bytes long and output is 8 bytes.
|
|
(the des_cblock structure is 8 chars).
|
|
|
|
void des_ecb3_encrypt(
|
|
des_cblock *input,
|
|
des_cblock *output,
|
|
des_key_schedule ks1,
|
|
des_key_schedule ks2,
|
|
des_key_schedule ks3,
|
|
int enc);
|
|
This is the 3 key EDE mode of ECB DES. What this means is that
|
|
the 8 bytes of input is encrypted with ks1, decrypted with ks2 and
|
|
then encrypted again with ks3, before being put into output;
|
|
C=E(ks3,D(ks2,E(ks1,M))). There is a macro, des_ecb2_encrypt()
|
|
that only takes 2 des_key_schedules that implements,
|
|
C=E(ks1,D(ks2,E(ks1,M))) in that the final encrypt is done with ks1.
|
|
|
|
void des_cbc_encrypt(
|
|
des_cblock *input,
|
|
des_cblock *output,
|
|
long length,
|
|
des_key_schedule ks,
|
|
des_cblock *ivec,
|
|
int enc);
|
|
This routine implements DES in Cipher Block Chaining mode.
|
|
Input, which should be a multiple of 8 bytes is encrypted
|
|
(or decrypted) to output which will also be a multiple of 8 bytes.
|
|
The number of bytes is in length (and from what I've said above,
|
|
should be a multiple of 8). If length is not a multiple of 8, I'm
|
|
not being held responsible :-). ivec is the initialisation vector.
|
|
This function does not modify this variable. To correctly implement
|
|
cbc mode, you need to do one of 2 things; copy the last 8 bytes of
|
|
cipher text for use as the next ivec in your application,
|
|
or use des_ncbc_encrypt().
|
|
Only this routine has this problem with updating the ivec, all
|
|
other routines that are implementing cbc mode update ivec.
|
|
|
|
void des_ncbc_encrypt(
|
|
des_cblock *input,
|
|
des_cblock *output,
|
|
long length,
|
|
des_key_schedule sk,
|
|
des_cblock *ivec,
|
|
int enc);
|
|
For historical reasons, des_cbc_encrypt() did not update the
|
|
ivec with the value requires so that subsequent calls to
|
|
des_cbc_encrypt() would 'chain'. This was needed so that the same
|
|
'length' values would not need to be used when decrypting.
|
|
des_ncbc_encrypt() does the right thing. It is the same as
|
|
des_cbc_encrypt accept that ivec is updates with the correct value
|
|
to pass in subsequent calls to des_ncbc_encrypt(). I advise using
|
|
des_ncbc_encrypt() instead of des_cbc_encrypt();
|
|
|
|
void des_xcbc_encrypt(
|
|
des_cblock *input,
|
|
des_cblock *output,
|
|
long length,
|
|
des_key_schedule sk,
|
|
des_cblock *ivec,
|
|
des_cblock *inw,
|
|
des_cblock *outw,
|
|
int enc);
|
|
This is RSA's DESX mode of DES. It uses inw and outw to
|
|
'whiten' the encryption. inw and outw are secret (unlike the iv)
|
|
and are as such, part of the key. So the key is sort of 24 bytes.
|
|
This is much better than cbc des.
|
|
|
|
void des_3cbc_encrypt(
|
|
des_cblock *input,
|
|
des_cblock *output,
|
|
long length,
|
|
des_key_schedule sk1,
|
|
des_key_schedule sk2,
|
|
des_cblock *ivec1,
|
|
des_cblock *ivec2,
|
|
int enc);
|
|
This function is flawed, do not use it. I have left it in the
|
|
library because it is used in my des(1) program and will function
|
|
correctly when used by des(1). If I removed the function, people
|
|
could end up unable to decrypt files.
|
|
This routine implements outer triple cbc encryption using 2 ks and
|
|
2 ivec's. Use des_ede2_cbc_encrypt() instead.
|
|
|
|
void des_ede3_cbc_encrypt(
|
|
des_cblock *input,
|
|
des_cblock *output,
|
|
long length,
|
|
des_key_schedule ks1,
|
|
des_key_schedule ks2,
|
|
des_key_schedule ks3,
|
|
des_cblock *ivec,
|
|
int enc);
|
|
This function implements outer triple CBC DES encryption with 3
|
|
keys. What this means is that each 'DES' operation
|
|
inside the cbc mode is really an C=E(ks3,D(ks2,E(ks1,M))).
|
|
Again, this is cbc mode so an ivec is requires.
|
|
This mode is used by SSL.
|
|
There is also a des_ede2_cbc_encrypt() that only uses 2
|
|
des_key_schedule's, the first being reused for the final
|
|
encryption. C=E(ks1,D(ks2,E(ks1,M))). This form of triple DES
|
|
is used by the RSAref library.
|
|
|
|
void des_pcbc_encrypt(
|
|
des_cblock *input,
|
|
des_cblock *output,
|
|
long length,
|
|
des_key_schedule ks,
|
|
des_cblock *ivec,
|
|
int enc);
|
|
This is Propagating Cipher Block Chaining mode of DES. It is used
|
|
by Kerberos v4. It's parameters are the same as des_ncbc_encrypt().
|
|
|
|
void des_cfb_encrypt(
|
|
unsigned char *in,
|
|
unsigned char *out,
|
|
int numbits,
|
|
long length,
|
|
des_key_schedule ks,
|
|
des_cblock *ivec,
|
|
int enc);
|
|
Cipher Feedback Back mode of DES. This implementation 'feeds back'
|
|
in numbit blocks. The input (and output) is in multiples of numbits
|
|
bits. numbits should to be a multiple of 8 bits. Length is the
|
|
number of bytes input. If numbits is not a multiple of 8 bits,
|
|
the extra bits in the bytes will be considered padding. So if
|
|
numbits is 12, for each 2 input bytes, the 4 high bits of the
|
|
second byte will be ignored. So to encode 72 bits when using
|
|
a numbits of 12 take 12 bytes. To encode 72 bits when using
|
|
numbits of 9 will take 16 bytes. To encode 80 bits when using
|
|
numbits of 16 will take 10 bytes. etc, etc. This padding will
|
|
apply to both input and output.
|
|
|
|
|
|
void des_cfb64_encrypt(
|
|
unsigned char *in,
|
|
unsigned char *out,
|
|
long length,
|
|
des_key_schedule ks,
|
|
des_cblock *ivec,
|
|
int *num,
|
|
int enc);
|
|
This is one of the more useful functions in this DES library, it
|
|
implements CFB mode of DES with 64bit feedback. Why is this
|
|
useful you ask? Because this routine will allow you to encrypt an
|
|
arbitrary number of bytes, no 8 byte padding. Each call to this
|
|
routine will encrypt the input bytes to output and then update ivec
|
|
and num. num contains 'how far' we are though ivec. If this does
|
|
not make much sense, read more about cfb mode of DES :-).
|
|
|
|
void des_ede3_cfb64_encrypt(
|
|
unsigned char *in,
|
|
unsigned char *out,
|
|
long length,
|
|
des_key_schedule ks1,
|
|
des_key_schedule ks2,
|
|
des_key_schedule ks3,
|
|
des_cblock *ivec,
|
|
int *num,
|
|
int enc);
|
|
Same as des_cfb64_encrypt() accept that the DES operation is
|
|
triple DES. As usual, there is a macro for
|
|
des_ede2_cfb64_encrypt() which reuses ks1.
|
|
|
|
void des_ofb_encrypt(
|
|
unsigned char *in,
|
|
unsigned char *out,
|
|
int numbits,
|
|
long length,
|
|
des_key_schedule ks,
|
|
des_cblock *ivec);
|
|
This is a implementation of Output Feed Back mode of DES. It is
|
|
the same as des_cfb_encrypt() in that numbits is the size of the
|
|
units dealt with during input and output (in bits).
|
|
|
|
void des_ofb64_encrypt(
|
|
unsigned char *in,
|
|
unsigned char *out,
|
|
long length,
|
|
des_key_schedule ks,
|
|
des_cblock *ivec,
|
|
int *num);
|
|
The same as des_cfb64_encrypt() except that it is Output Feed Back
|
|
mode.
|
|
|
|
void des_ede3_ofb64_encrypt(
|
|
unsigned char *in,
|
|
unsigned char *out,
|
|
long length,
|
|
des_key_schedule ks1,
|
|
des_key_schedule ks2,
|
|
des_key_schedule ks3,
|
|
des_cblock *ivec,
|
|
int *num);
|
|
Same as des_ofb64_encrypt() accept that the DES operation is
|
|
triple DES. As usual, there is a macro for
|
|
des_ede2_ofb64_encrypt() which reuses ks1.
|
|
|
|
int des_read_pw_string(
|
|
char *buf,
|
|
int length,
|
|
char *prompt,
|
|
int verify);
|
|
This routine is used to get a password from the terminal with echo
|
|
turned off. Buf is where the string will end up and length is the
|
|
size of buf. Prompt is a string presented to the 'user' and if
|
|
verify is set, the key is asked for twice and unless the 2 copies
|
|
match, an error is returned. A return code of -1 indicates a
|
|
system error, 1 failure due to use interaction, and 0 is success.
|
|
|
|
unsigned long des_cbc_cksum(
|
|
des_cblock *input,
|
|
des_cblock *output,
|
|
long length,
|
|
des_key_schedule ks,
|
|
des_cblock *ivec);
|
|
This function produces an 8 byte checksum from input that it puts in
|
|
output and returns the last 4 bytes as a long. The checksum is
|
|
generated via cbc mode of DES in which only the last 8 byes are
|
|
kept. I would recommend not using this function but instead using
|
|
the EVP_Digest routines, or at least using MD5 or SHA. This
|
|
function is used by Kerberos v4 so that is why it stays in the
|
|
library.
|
|
|
|
char *des_fcrypt(
|
|
const char *buf,
|
|
const char *salt
|
|
char *ret);
|
|
This is my fast version of the unix crypt(3) function. This version
|
|
takes only a small amount of space relative to other fast
|
|
crypt() implementations. This is different to the normal crypt
|
|
in that the third parameter is the buffer that the return value
|
|
is written into. It needs to be at least 14 bytes long. This
|
|
function is thread safe, unlike the normal crypt.
|
|
|
|
char *crypt(
|
|
const char *buf,
|
|
const char *salt);
|
|
This function calls des_fcrypt() with a static array passed as the
|
|
third parameter. This emulates the normal non-thread safe semantics
|
|
of crypt(3).
|
|
|
|
void des_string_to_key(
|
|
char *str,
|
|
des_cblock *key);
|
|
This function takes str and converts it into a DES key. I would
|
|
recommend using MD5 instead and use the first 8 bytes of output.
|
|
When I wrote the first version of these routines back in 1990, MD5
|
|
did not exist but I feel these routines are still sound. This
|
|
routines is compatible with the one in MIT's libdes.
|
|
|
|
void des_string_to_2keys(
|
|
char *str,
|
|
des_cblock *key1,
|
|
des_cblock *key2);
|
|
This function takes str and converts it into 2 DES keys.
|
|
I would recommend using MD5 and using the 16 bytes as the 2 keys.
|
|
I have nothing against these 2 'string_to_key' routines, it's just
|
|
that if you say that your encryption key is generated by using the
|
|
16 bytes of an MD5 hash, every-one knows how you generated your
|
|
keys.
|
|
|
|
int des_read_password(
|
|
des_cblock *key,
|
|
char *prompt,
|
|
int verify);
|
|
This routine combines des_read_pw_string() with des_string_to_key().
|
|
|
|
int des_read_2passwords(
|
|
des_cblock *key1,
|
|
des_cblock *key2,
|
|
char *prompt,
|
|
int verify);
|
|
This routine combines des_read_pw_string() with des_string_to_2key().
|
|
|
|
void des_random_seed(
|
|
des_cblock key);
|
|
This routine sets a starting point for des_random_key().
|
|
|
|
void des_random_key(
|
|
des_cblock ret);
|
|
This function return a random key. Make sure to 'seed' the random
|
|
number generator (with des_random_seed()) before using this function.
|
|
I personally now use a MD5 based random number system.
|
|
|
|
int des_enc_read(
|
|
int fd,
|
|
char *buf,
|
|
int len,
|
|
des_key_schedule ks,
|
|
des_cblock *iv);
|
|
This function will write to a file descriptor the encrypted data
|
|
from buf. This data will be preceded by a 4 byte 'byte count' and
|
|
will be padded out to 8 bytes. The encryption is either CBC of
|
|
PCBC depending on the value of des_rw_mode. If it is DES_PCBC_MODE,
|
|
pcbc is used, if DES_CBC_MODE, cbc is used. The default is to use
|
|
DES_PCBC_MODE.
|
|
|
|
int des_enc_write(
|
|
int fd,
|
|
char *buf,
|
|
int len,
|
|
des_key_schedule ks,
|
|
des_cblock *iv);
|
|
This routines read stuff written by des_enc_read() and decrypts it.
|
|
I have used these routines quite a lot but I don't believe they are
|
|
suitable for non-blocking io. If you are after a full
|
|
authentication/encryption over networks, have a look at SSL instead.
|
|
|
|
unsigned long des_quad_cksum(
|
|
des_cblock *input,
|
|
des_cblock *output,
|
|
long length,
|
|
int out_count,
|
|
des_cblock *seed);
|
|
This is a function from Kerberos v4 that is not anything to do with
|
|
DES but was needed. It is a cksum that is quicker to generate than
|
|
des_cbc_cksum(); I personally would use MD5 routines now.
|
|
=====
|
|
Modes of DES
|
|
Quite a bit of the following information has been taken from
|
|
AS 2805.5.2
|
|
Australian Standard
|
|
Electronic funds transfer - Requirements for interfaces,
|
|
Part 5.2: Modes of operation for an n-bit block cipher algorithm
|
|
Appendix A
|
|
|
|
There are several different modes in which DES can be used, they are
|
|
as follows.
|
|
|
|
Electronic Codebook Mode (ECB) (des_ecb_encrypt())
|
|
- 64 bits are enciphered at a time.
|
|
- The order of the blocks can be rearranged without detection.
|
|
- The same plaintext block always produces the same ciphertext block
|
|
(for the same key) making it vulnerable to a 'dictionary attack'.
|
|
- An error will only affect one ciphertext block.
|
|
|
|
Cipher Block Chaining Mode (CBC) (des_cbc_encrypt())
|
|
- a multiple of 64 bits are enciphered at a time.
|
|
- The CBC mode produces the same ciphertext whenever the same
|
|
plaintext is encrypted using the same key and starting variable.
|
|
- The chaining operation makes the ciphertext blocks dependent on the
|
|
current and all preceding plaintext blocks and therefore blocks can not
|
|
be rearranged.
|
|
- The use of different starting variables prevents the same plaintext
|
|
enciphering to the same ciphertext.
|
|
- An error will affect the current and the following ciphertext blocks.
|
|
|
|
Cipher Feedback Mode (CFB) (des_cfb_encrypt())
|
|
- a number of bits (j) <= 64 are enciphered at a time.
|
|
- The CFB mode produces the same ciphertext whenever the same
|
|
plaintext is encrypted using the same key and starting variable.
|
|
- The chaining operation makes the ciphertext variables dependent on the
|
|
current and all preceding variables and therefore j-bit variables are
|
|
chained together and can not be rearranged.
|
|
- The use of different starting variables prevents the same plaintext
|
|
enciphering to the same ciphertext.
|
|
- The strength of the CFB mode depends on the size of k (maximal if
|
|
j == k). In my implementation this is always the case.
|
|
- Selection of a small value for j will require more cycles through
|
|
the encipherment algorithm per unit of plaintext and thus cause
|
|
greater processing overheads.
|
|
- Only multiples of j bits can be enciphered.
|
|
- An error will affect the current and the following ciphertext variables.
|
|
|
|
Output Feedback Mode (OFB) (des_ofb_encrypt())
|
|
- a number of bits (j) <= 64 are enciphered at a time.
|
|
- The OFB mode produces the same ciphertext whenever the same
|
|
plaintext enciphered using the same key and starting variable. More
|
|
over, in the OFB mode the same key stream is produced when the same
|
|
key and start variable are used. Consequently, for security reasons
|
|
a specific start variable should be used only once for a given key.
|
|
- The absence of chaining makes the OFB more vulnerable to specific attacks.
|
|
- The use of different start variables values prevents the same
|
|
plaintext enciphering to the same ciphertext, by producing different
|
|
key streams.
|
|
- Selection of a small value for j will require more cycles through
|
|
the encipherment algorithm per unit of plaintext and thus cause
|
|
greater processing overheads.
|
|
- Only multiples of j bits can be enciphered.
|
|
- OFB mode of operation does not extend ciphertext errors in the
|
|
resultant plaintext output. Every bit error in the ciphertext causes
|
|
only one bit to be in error in the deciphered plaintext.
|
|
- OFB mode is not self-synchronising. If the two operation of
|
|
encipherment and decipherment get out of synchronism, the system needs
|
|
to be re-initialised.
|
|
- Each re-initialisation should use a value of the start variable
|
|
different from the start variable values used before with the same
|
|
key. The reason for this is that an identical bit stream would be
|
|
produced each time from the same parameters. This would be
|
|
susceptible to a ' known plaintext' attack.
|
|
|
|
Triple ECB Mode (des_ecb3_encrypt())
|
|
- Encrypt with key1, decrypt with key2 and encrypt with key3 again.
|
|
- As for ECB encryption but increases the key length to 168 bits.
|
|
There are theoretic attacks that can be used that make the effective
|
|
key length 112 bits, but this attack also requires 2^56 blocks of
|
|
memory, not very likely, even for the NSA.
|
|
- If both keys are the same it is equivalent to encrypting once with
|
|
just one key.
|
|
- If the first and last key are the same, the key length is 112 bits.
|
|
There are attacks that could reduce the key space to 55 bit's but it
|
|
requires 2^56 blocks of memory.
|
|
- If all 3 keys are the same, this is effectively the same as normal
|
|
ecb mode.
|
|
|
|
Triple CBC Mode (des_ede3_cbc_encrypt())
|
|
- Encrypt with key1, decrypt with key2 and then encrypt with key3.
|
|
- As for CBC encryption but increases the key length to 168 bits with
|
|
the same restrictions as for triple ecb mode.
|
|
|
|
==== digest.doc ========================================================
|
|
|
|
|
|
The Message Digest subroutines.
|
|
|
|
These routines require "evp.h" to be included.
|
|
|
|
These functions are a higher level interface to the various message digest
|
|
routines found in this library. As such, they allow the same code to be
|
|
used to digest via different algorithms with only a change in an initial
|
|
parameter. They are basically just a front-end to the MD2, MD5, SHA
|
|
and SHA1
|
|
routines.
|
|
|
|
These routines all take a pointer to the following structure to specify
|
|
which message digest algorithm to use.
|
|
typedef struct evp_md_st
|
|
{
|
|
int type;
|
|
int pkey_type;
|
|
int md_size;
|
|
void (*init)();
|
|
void (*update)();
|
|
void (*final)();
|
|
|
|
int required_pkey_type; /*EVP_PKEY_xxx */
|
|
int (*sign)();
|
|
int (*verify)();
|
|
} EVP_MD;
|
|
|
|
If additional message digest algorithms are to be supported, a structure of
|
|
this type needs to be declared and populated and then the Digest routines
|
|
can be used with that algorithm. The type field is the object NID of the
|
|
digest type (read the section on Objects for an explanation). The pkey_type
|
|
is the Object type to use when the a message digest is generated by there
|
|
routines and then is to be signed with the pkey algorithm. Md_size is
|
|
the size of the message digest returned. Init, update
|
|
and final are the relevant functions to perform the message digest function
|
|
by parts. One reason for specifying the message digest to use via this
|
|
mechanism is that if you only use md5, only the md5 routines will
|
|
be included in you linked program. If you passed an integer
|
|
that specified which message digest to use, the routine that mapped that
|
|
integer to a set of message digest functions would cause all the message
|
|
digests functions to be link into the code. This setup also allows new
|
|
message digest functions to be added by the application.
|
|
|
|
The six message digests defined in this library are
|
|
|
|
EVP_MD *EVP_md2(void); /* RSA sign/verify */
|
|
EVP_MD *EVP_md5(void); /* RSA sign/verify */
|
|
EVP_MD *EVP_sha(void); /* RSA sign/verify */
|
|
EVP_MD *EVP_sha1(void); /* RSA sign/verify */
|
|
EVP_MD *EVP_dss(void); /* DSA sign/verify */
|
|
EVP_MD *EVP_dss1(void); /* DSA sign/verify */
|
|
|
|
All the message digest routines take a EVP_MD_CTX pointer as an argument.
|
|
The state of the message digest is kept in this structure.
|
|
|
|
typedef struct pem_md_ctx_st
|
|
{
|
|
EVP_MD *digest;
|
|
union {
|
|
unsigned char base[4]; /* this is used in my library as a
|
|
* 'pointer' to all union elements
|
|
* structures. */
|
|
MD2_CTX md2;
|
|
MD5_CTX md5;
|
|
SHA_CTX sha;
|
|
} md;
|
|
} EVP_MD_CTX;
|
|
|
|
The Digest functions are as follows.
|
|
|
|
void EVP_DigestInit(
|
|
EVP_MD_CTX *ctx,
|
|
EVP_MD *type);
|
|
This function is used to initialise the EVP_MD_CTX. The message
|
|
digest that will associated with 'ctx' is specified by 'type'.
|
|
|
|
void EVP_DigestUpdate(
|
|
EVP_MD_CTX *ctx,
|
|
unsigned char *data,
|
|
unsigned int cnt);
|
|
This function is used to pass more data to the message digest
|
|
function. 'cnt' bytes are digested from 'data'.
|
|
|
|
void EVP_DigestFinal(
|
|
EVP_MD_CTX *ctx,
|
|
unsigned char *md,
|
|
unsigned int *len);
|
|
This function finishes the digestion and puts the message digest
|
|
into 'md'. The length of the message digest is put into len;
|
|
EVP_MAX_MD_SIZE is the size of the largest message digest that
|
|
can be returned from this function. Len can be NULL if the
|
|
size of the digest is not required.
|
|
|
|
|
|
==== encode.doc ========================================================
|
|
|
|
|
|
void EVP_EncodeInit(EVP_ENCODE_CTX *ctx);
|
|
void EVP_EncodeUpdate(EVP_ENCODE_CTX *ctx,unsigned char *out,
|
|
int *outl,unsigned char *in,int inl);
|
|
void EVP_EncodeFinal(EVP_ENCODE_CTX *ctx,unsigned char *out,int *outl);
|
|
int EVP_EncodeBlock(unsigned char *t, unsigned char *f, int n);
|
|
|
|
void EVP_DecodeInit(EVP_ENCODE_CTX *ctx);
|
|
int EVP_DecodeUpdate(EVP_ENCODE_CTX *ctx,unsigned char *out,int *outl,
|
|
unsigned char *in, int inl);
|
|
int EVP_DecodeFinal(EVP_ENCODE_CTX *ctx, unsigned
|
|
char *out, int *outl);
|
|
int EVP_DecodeBlock(unsigned char *t, unsigned
|
|
char *f, int n);
|
|
|
|
|
|
==== envelope.doc ========================================================
|
|
|
|
The following routines are use to create 'digital' envelopes.
|
|
By this I mean that they perform various 'higher' level cryptographic
|
|
functions. Have a read of 'cipher.doc' and 'digest.doc' since those
|
|
routines are used by these functions.
|
|
cipher.doc contains documentation about the cipher part of the
|
|
envelope library and digest.doc contatins the description of the
|
|
message digests supported.
|
|
|
|
To 'sign' a document involves generating a message digest and then encrypting
|
|
the digest with an private key.
|
|
|
|
#define EVP_SignInit(a,b) EVP_DigestInit(a,b)
|
|
#define EVP_SignUpdate(a,b,c) EVP_DigestUpdate(a,b,c)
|
|
Due to the fact this operation is basically just an extended message
|
|
digest, the first 2 functions are macro calls to Digest generating
|
|
functions.
|
|
|
|
int EVP_SignFinal(
|
|
EVP_MD_CTX *ctx,
|
|
unsigned char *md,
|
|
unsigned int *s,
|
|
EVP_PKEY *pkey);
|
|
This finalisation function finishes the generation of the message
|
|
digest and then encrypts the digest (with the correct message digest
|
|
object identifier) with the EVP_PKEY private key. 'ctx' is the message digest
|
|
context. 'md' will end up containing the encrypted message digest. This
|
|
array needs to be EVP_PKEY_size(pkey) bytes long. 's' will actually
|
|
contain the exact length. 'pkey' of course is the private key. It is
|
|
one of EVP_PKEY_RSA or EVP_PKEY_DSA type.
|
|
If there is an error, 0 is returned, otherwise 1.
|
|
|
|
Verify is used to check an signed message digest.
|
|
|
|
#define EVP_VerifyInit(a,b) EVP_DigestInit(a,b)
|
|
#define EVP_VerifyUpdate(a,b,c) EVP_DigestUpdate(a,b,c)
|
|
Since the first step is to generate a message digest, the first 2 functions
|
|
are macros.
|
|
|
|
int EVP_VerifyFinal(
|
|
EVP_MD_CTX *ctx,
|
|
unsigned char *md,
|
|
unsigned int s,
|
|
EVP_PKEY *pkey);
|
|
This function finishes the generation of the message digest and then
|
|
compares it with the supplied encrypted message digest. 'md' contains the
|
|
's' bytes of encrypted message digest. 'pkey' is used to public key decrypt
|
|
the digest. It is then compared with the message digest just generated.
|
|
If they match, 1 is returned else 0.
|
|
|
|
int EVP_SealInit(EVP_CIPHER_CTX *ctx, EVP_CIPHER *type, unsigned char **ek,
|
|
int *ekl, unsigned char *iv, EVP_PKEY **pubk, int npubk);
|
|
Must have at least one public key, error is 0. I should also mention that
|
|
the buffers pointed to by 'ek' need to be EVP_PKEY_size(pubk[n]) is size.
|
|
|
|
#define EVP_SealUpdate(a,b,c,d,e) EVP_EncryptUpdate(a,b,c,d,e)
|
|
void EVP_SealFinal(EVP_CIPHER_CTX *ctx,unsigned char *out,int *outl);
|
|
|
|
|
|
int EVP_OpenInit(EVP_CIPHER_CTX *ctx,EVP_CIPHER *type,unsigned char *ek,
|
|
int ekl,unsigned char *iv,EVP_PKEY *priv);
|
|
0 on failure
|
|
|
|
#define EVP_OpenUpdate(a,b,c,d,e) EVP_DecryptUpdate(a,b,c,d,e)
|
|
|
|
int EVP_OpenFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl);
|
|
Decrypt final return code
|
|
|
|
|
|
==== error.doc ========================================================
|
|
|
|
The error routines.
|
|
|
|
The 'error' system I've implemented is intended to server 2 purpose, to
|
|
record the reason why a command failed and to record where in the libraries
|
|
the failure occurred. It is more or less setup to record a 'trace' of which
|
|
library components were being traversed when the error occurred.
|
|
|
|
When an error is recorded, it is done so a as single unsigned long which is
|
|
composed of three parts. The top byte is the 'library' number, the middle
|
|
12 bytes is the function code, and the bottom 12 bits is the 'reason' code.
|
|
|
|
Each 'library', or should a say, 'section' of the SSLeay library has a
|
|
different unique 'library' error number. Each function in the library has
|
|
a number that is unique for that library. Each 'library' also has a number
|
|
for each 'error reason' that is only unique for that 'library'.
|
|
|
|
Due to the way these error routines record a 'error trace', there is an
|
|
array per thread that is used to store the error codes.
|
|
The various functions in this library are used to access
|
|
and manipulate this array.
|
|
|
|
void ERR_put_error(int lib, int func,int reason);
|
|
This routine records an error in library 'lib', function 'func'
|
|
and reason 'reason'. As errors get 'put' into the buffer, they wrap
|
|
around and overwrite old errors if too many are written. It is assumed
|
|
that the last errors are the most important.
|
|
|
|
unsigned long ERR_get_error(void );
|
|
This function returns the last error added to the error buffer.
|
|
In effect it is popping the value off the buffer so repeated calls will
|
|
continue to return values until there are no more errors to return in which
|
|
case 0 is returned.
|
|
|
|
unsigned long ERR_peek_error(void );
|
|
This function returns the value of the last error added to the
|
|
error buffer but does not 'pop' it from the buffer.
|
|
|
|
void ERR_clear_error(void );
|
|
This function clears the error buffer, discarding all unread
|
|
errors.
|
|
|
|
While the above described error system obviously produces lots of different
|
|
error number, a method for 'reporting' these errors in a human readable
|
|
form is required. To achieve this, each library has the option of
|
|
'registering' error strings.
|
|
|
|
typedef struct ERR_string_data_st
|
|
{
|
|
unsigned long error;
|
|
char *string;
|
|
} ERR_STRING_DATA;
|
|
|
|
The 'ERR_STRING_DATA' contains an error code and the corresponding text
|
|
string. To add new function error strings for a library, the
|
|
ERR_STRING_DATA needs to be 'registered' with the library.
|
|
|
|
void ERR_load_strings(unsigned long lib,ERR_STRING_DATA *err);
|
|
This function 'registers' the array of ERR_STRING_DATA pointed to by
|
|
'err' as error text strings for the error library 'lib'.
|
|
|
|
void ERR_free_strings(void);
|
|
This function free()s all the loaded error strings.
|
|
|
|
char *ERR_error_string(unsigned long error,char *buf);
|
|
This function returns a text string that is a human readable
|
|
version of the error represented by 'error'. Buff should be at least 120
|
|
bytes long and if it is NULL, the return value is a pointer to a static
|
|
variable that will contain the error string, otherwise 'buf' is returned.
|
|
If there is not a text string registered for a particular error, a text
|
|
string containing the error number is returned instead.
|
|
|
|
void ERR_print_errors(BIO *bp);
|
|
void ERR_print_errors_fp(FILE *fp);
|
|
This function is a convenience routine that prints the error string
|
|
for each error until all errors have been accounted for.
|
|
|
|
char *ERR_lib_error_string(unsigned long e);
|
|
char *ERR_func_error_string(unsigned long e);
|
|
char *ERR_reason_error_string(unsigned long e);
|
|
The above three functions return the 3 different components strings for the
|
|
error 'e'. ERR_error_string() uses these functions.
|
|
|
|
void ERR_load_ERR_strings(void );
|
|
This function 'registers' the error strings for the 'ERR' module.
|
|
|
|
void ERR_load_crypto_strings(void );
|
|
This function 'register' the error strings for just about every
|
|
library in the SSLeay package except for the SSL routines. There is no
|
|
need to ever register any error text strings and you will probably save in
|
|
program size. If on the other hand you do 'register' all errors, it is
|
|
quite easy to determine why a particular routine failed.
|
|
|
|
As a final footnote as to why the error system is designed as it is.
|
|
1) I did not want a single 'global' error code.
|
|
2) I wanted to know which subroutine a failure occurred in.
|
|
3) For Windows NT etc, it should be simple to replace the 'key' routines
|
|
with code to pass error codes back to the application.
|
|
4) I wanted the option of meaningful error text strings.
|
|
|
|
Late breaking news - the changes to support threads.
|
|
|
|
Each 'thread' has an 'ERR_STATE' state associated with it.
|
|
ERR_STATE *ERR_get_state(void ) will return the 'state' for the calling
|
|
thread/process.
|
|
|
|
ERR_remove_state(unsigned long pid); will 'free()' this state. If pid == 0
|
|
the current 'thread/process' will have it's error state removed.
|
|
If you do not remove the error state of a thread, this could be considered a
|
|
form of memory leak, so just after 'reaping' a thread that has died,
|
|
call ERR_remove_state(pid).
|
|
|
|
Have a read of thread.doc for more details for what is required for
|
|
multi-threading support. All the other error routines will
|
|
work correctly when using threads.
|
|
|
|
|
|
==== idea.doc ========================================================
|
|
|
|
The IDEA library.
|
|
IDEA is a block cipher that operates on 64bit (8 byte) quantities. It
|
|
uses a 128bit (16 byte) key. It can be used in all the modes that DES can
|
|
be used. This library implements the ecb, cbc, cfb64 and ofb64 modes.
|
|
|
|
For all calls that have an 'input' and 'output' variables, they can be the
|
|
same.
|
|
|
|
This library requires the inclusion of 'idea.h'.
|
|
|
|
All of the encryption functions take what is called an IDEA_KEY_SCHEDULE as an
|
|
argument. An IDEA_KEY_SCHEDULE is an expanded form of the idea key.
|
|
For all modes of the IDEA algorithm, the IDEA_KEY_SCHEDULE used for
|
|
decryption is different to the one used for encryption.
|
|
|
|
The define IDEA_ENCRYPT is passed to specify encryption for the functions
|
|
that require an encryption/decryption flag. IDEA_DECRYPT is passed to
|
|
specify decryption. For some mode there is no encryption/decryption
|
|
flag since this is determined by the IDEA_KEY_SCHEDULE.
|
|
|
|
So to encrypt you would do the following
|
|
idea_set_encrypt_key(key,encrypt_ks);
|
|
idea_ecb_encrypt(...,encrypt_ks);
|
|
idea_cbc_encrypt(....,encrypt_ks,...,IDEA_ENCRYPT);
|
|
|
|
To Decrypt
|
|
idea_set_encrypt_key(key,encrypt_ks);
|
|
idea_set_decrypt_key(encrypt_ks,decrypt_ks);
|
|
idea_ecb_encrypt(...,decrypt_ks);
|
|
idea_cbc_encrypt(....,decrypt_ks,...,IDEA_DECRYPT);
|
|
|
|
Please note that any of the encryption modes specified in my DES library
|
|
could be used with IDEA. I have only implemented ecb, cbc, cfb64 and
|
|
ofb64 for the following reasons.
|
|
- ecb is the basic IDEA encryption.
|
|
- cbc is the normal 'chaining' form for block ciphers.
|
|
- cfb64 can be used to encrypt single characters, therefore input and output
|
|
do not need to be a multiple of 8.
|
|
- ofb64 is similar to cfb64 but is more like a stream cipher, not as
|
|
secure (not cipher feedback) but it does not have an encrypt/decrypt mode.
|
|
- If you want triple IDEA, thats 384 bits of key and you must be totally
|
|
obsessed with security. Still, if you want it, it is simple enough to
|
|
copy the function from the DES library and change the des_encrypt to
|
|
idea_encrypt; an exercise left for the paranoid reader :-).
|
|
|
|
The functions are as follows:
|
|
|
|
void idea_set_encrypt_key(
|
|
unsigned char *key;
|
|
IDEA_KEY_SCHEDULE *ks);
|
|
idea_set_encrypt_key converts a 16 byte IDEA key into an
|
|
IDEA_KEY_SCHEDULE. The IDEA_KEY_SCHEDULE is an expanded form of
|
|
the key which can be used to perform IDEA encryption.
|
|
An IDEA_KEY_SCHEDULE is an expanded form of the key which is used to
|
|
perform actual encryption. It can be regenerated from the IDEA key
|
|
so it only needs to be kept when encryption is about
|
|
to occur. Don't save or pass around IDEA_KEY_SCHEDULE's since they
|
|
are CPU architecture dependent, IDEA keys are not.
|
|
|
|
void idea_set_decrypt_key(
|
|
IDEA_KEY_SCHEDULE *encrypt_ks,
|
|
IDEA_KEY_SCHEDULE *decrypt_ks);
|
|
This functions converts an encryption IDEA_KEY_SCHEDULE into a
|
|
decryption IDEA_KEY_SCHEDULE. For all decryption, this conversion
|
|
of the key must be done. In some modes of IDEA, an
|
|
encryption/decryption flag is also required, this is because these
|
|
functions involve block chaining and the way this is done changes
|
|
depending on which of encryption of decryption is being done.
|
|
Please note that there is no quick way to generate the decryption
|
|
key schedule other than generating the encryption key schedule and
|
|
then converting it.
|
|
|
|
void idea_encrypt(
|
|
unsigned long *data,
|
|
IDEA_KEY_SCHEDULE *ks);
|
|
This is the IDEA encryption function that gets called by just about
|
|
every other IDEA routine in the library. You should not use this
|
|
function except to implement 'modes' of IDEA. I say this because the
|
|
functions that call this routine do the conversion from 'char *' to
|
|
long, and this needs to be done to make sure 'non-aligned' memory
|
|
access do not occur.
|
|
Data is a pointer to 2 unsigned long's and ks is the
|
|
IDEA_KEY_SCHEDULE to use. Encryption or decryption depends on the
|
|
IDEA_KEY_SCHEDULE.
|
|
|
|
void idea_ecb_encrypt(
|
|
unsigned char *input,
|
|
unsigned char *output,
|
|
IDEA_KEY_SCHEDULE *ks);
|
|
This is the basic Electronic Code Book form of IDEA (in DES this
|
|
mode is called Electronic Code Book so I'm going to use the term
|
|
for idea as well :-).
|
|
Input is encrypted into output using the key represented by
|
|
ks. Depending on the IDEA_KEY_SCHEDULE, encryption or
|
|
decryption occurs. Input is 8 bytes long and output is 8 bytes.
|
|
|
|
void idea_cbc_encrypt(
|
|
unsigned char *input,
|
|
unsigned char *output,
|
|
long length,
|
|
IDEA_KEY_SCHEDULE *ks,
|
|
unsigned char *ivec,
|
|
int enc);
|
|
This routine implements IDEA in Cipher Block Chaining mode.
|
|
Input, which should be a multiple of 8 bytes is encrypted
|
|
(or decrypted) to output which will also be a multiple of 8 bytes.
|
|
The number of bytes is in length (and from what I've said above,
|
|
should be a multiple of 8). If length is not a multiple of 8, bad
|
|
things will probably happen. ivec is the initialisation vector.
|
|
This function updates iv after each call so that it can be passed to
|
|
the next call to idea_cbc_encrypt().
|
|
|
|
void idea_cfb64_encrypt(
|
|
unsigned char *in,
|
|
unsigned char *out,
|
|
long length,
|
|
des_key_schedule ks,
|
|
des_cblock *ivec,
|
|
int *num,
|
|
int enc);
|
|
This is one of the more useful functions in this IDEA library, it
|
|
implements CFB mode of IDEA with 64bit feedback.
|
|
This allows you to encrypt an arbitrary number of bytes,
|
|
you do not require 8 byte padding. Each call to this
|
|
routine will encrypt the input bytes to output and then update ivec
|
|
and num. Num contains 'how far' we are though ivec.
|
|
Enc is used to indicate encryption or decryption.
|
|
One very important thing to remember is that when decrypting, use
|
|
the encryption form of the key.
|
|
CFB64 mode operates by using the cipher to
|
|
generate a stream of bytes which is used to encrypt the plain text.
|
|
The cipher text is then encrypted to generate the next 64 bits to
|
|
be xored (incrementally) with the next 64 bits of plain
|
|
text. As can be seen from this, to encrypt or decrypt,
|
|
the same 'cipher stream' needs to be generated but the way the next
|
|
block of data is gathered for encryption is different for
|
|
encryption and decryption. What this means is that to encrypt
|
|
idea_set_encrypt_key(key,ks);
|
|
idea_cfb64_encrypt(...,ks,..,IDEA_ENCRYPT)
|
|
do decrypt
|
|
idea_set_encrypt_key(key,ks)
|
|
idea_cfb64_encrypt(...,ks,...,IDEA_DECRYPT)
|
|
Note: The same IDEA_KEY_SCHEDULE but different encryption flags.
|
|
For idea_cbc or idea_ecb, idea_set_decrypt_key() would need to be
|
|
used to generate the IDEA_KEY_SCHEDULE for decryption.
|
|
The reason I'm stressing this point is that I just wasted 3 hours
|
|
today trying to decrypt using this mode and the decryption form of
|
|
the key :-(.
|
|
|
|
void idea_ofb64_encrypt(
|
|
unsigned char *in,
|
|
unsigned char *out,
|
|
long length,
|
|
des_key_schedule ks,
|
|
des_cblock *ivec,
|
|
int *num);
|
|
This functions implements OFB mode of IDEA with 64bit feedback.
|
|
This allows you to encrypt an arbitrary number of bytes,
|
|
you do not require 8 byte padding. Each call to this
|
|
routine will encrypt the input bytes to output and then update ivec
|
|
and num. Num contains 'how far' we are though ivec.
|
|
This is in effect a stream cipher, there is no encryption or
|
|
decryption mode. The same key and iv should be used to
|
|
encrypt and decrypt.
|
|
|
|
For reading passwords, I suggest using des_read_pw_string() from my DES library.
|
|
To generate a password from a text string, I suggest using MD5 (or MD2) to
|
|
produce a 16 byte message digest that can then be passed directly to
|
|
idea_set_encrypt_key().
|
|
|
|
=====
|
|
For more information about the specific IDEA modes in this library
|
|
(ecb, cbc, cfb and ofb), read the section entitled 'Modes of DES' from the
|
|
documentation on my DES library. What is said about DES is directly
|
|
applicable for IDEA.
|
|
|
|
|
|
==== legal.doc ========================================================
|
|
|
|
From eay@mincom.com Thu Jun 27 00:25:45 1996
|
|
Received: by orb.mincom.oz.au id AA15821
|
|
(5.65c/IDA-1.4.4 for eay); Wed, 26 Jun 1996 14:25:45 +1000
|
|
Date: Wed, 26 Jun 1996 14:25:45 +1000 (EST)
|
|
From: Eric Young <eay@mincom.oz.au>
|
|
X-Sender: eay@orb
|
|
To: Ken Toll <ktoll@ren.digitalage.com>
|
|
Cc: Eric Young <eay@mincom.oz.au>, ssl-talk@netscape.com
|
|
Subject: Re: Unidentified subject!
|
|
In-Reply-To: <9606261950.ZM28943@ren.digitalage.com>
|
|
Message-Id: <Pine.SOL.3.91.960626131156.28573K-100000@orb>
|
|
Mime-Version: 1.0
|
|
Content-Type: TEXT/PLAIN; charset=US-ASCII
|
|
Status: O
|
|
X-Status:
|
|
|
|
|
|
This is a little off topic but since SSLeay is a free implementation of
|
|
the SSLv2 protocol, I feel it is worth responding on the topic of if it
|
|
is actually legal for Americans to use free cryptographic software.
|
|
|
|
On Wed, 26 Jun 1996, Ken Toll wrote:
|
|
> Is the U.S the only country that SSLeay cannot be used commercially
|
|
> (because of RSAref) or is that going to be an issue with every country
|
|
> that a client/server application (non-web browser/server) is deployed
|
|
> and sold?
|
|
|
|
>From what I understand, the software patents that apply to algorithms
|
|
like RSA and DH only apply in the USA. The IDEA algorithm I believe is
|
|
patened in europe (USA?), but considing how little it is used by other SSL
|
|
implementations, it quite easily be left out of the SSLeay build
|
|
(this can be done with a compile flag).
|
|
|
|
Actually if the RSA patent did apply outside the USA, it could be rather
|
|
interesting since RSA is not alowed to let RSA toolkits outside of the USA
|
|
[1], and since these are the only forms that they will alow the algorithm
|
|
to be used in, it would mean that non-one outside of the USA could produce
|
|
public key software which would be a very strong statment for
|
|
international patent law to make :-). This logic is a little flawed but
|
|
it still points out some of the more interesting permutations of USA
|
|
patent law and ITAR restrictions.
|
|
|
|
Inside the USA there is also the unresolved issue of RC4/RC2 which were
|
|
made public on sci.crypt in Sep 1994 (RC4) and Feb 1996 (RC2). I have
|
|
copies of the origional postings if people are interested. RSA I believe
|
|
claim that they were 'trade-secrets' and that some-one broke an NDA in
|
|
revealing them. Other claim they reverse engineered the algorithms from
|
|
compiled binaries. If the algorithms were reverse engineered, I belive
|
|
RSA had no legal leg to stand on. If an NDA was broken, I don't know.
|
|
Regardless, RSA, I belive, is willing to go to court over the issue so
|
|
licencing is probably the best idea, or at least talk to them.
|
|
If there are people who actually know more about this, pease let me know, I
|
|
don't want to vilify or spread miss-information if I can help it.
|
|
|
|
If you are not producing a web browser, it is easy to build SSLeay with
|
|
RC2/RC4 removed. Since RC4 is the defacto standard cipher in
|
|
all web software (and it is damn fast) it is more or less required for
|
|
www use. For non www use of SSL, especially for an application where
|
|
interoperability with other vendors is not critical just leave it out.
|
|
|
|
Removing IDEA, RC2 and RC4 would only leave DES and Triple DES but
|
|
they should be ok. Considing that Triple DES can encrypt at rates of
|
|
410k/sec on a pentium 100, and 940k/sec on a P6/200, this is quite
|
|
reasonable performance. Single DES clocks in at 1160k/s and 2467k/s
|
|
respectivly is actually quite fast for those not so paranoid (56 bit key).[1]
|
|
|
|
> Is it possible to get a certificate for commercial use outside of the U.S.?
|
|
yes.
|
|
|
|
Thawte Consulting issues certificates (they are the people who sell the
|
|
Sioux httpd server and are based in South Africa)
|
|
Verisign will issue certificates for Sioux (sold from South Africa), so this
|
|
proves that they will issue certificate for OS use if they are
|
|
happy with the quality of the software.
|
|
|
|
(The above mentioned companies just the ones that I know for sure are issuing
|
|
certificates outside the USA).
|
|
|
|
There is always the point that if you are using SSL for an intra net,
|
|
SSLeay provides programs that can be used so you can issue your own
|
|
certificates. They need polishing but at least it is a good starting point.
|
|
|
|
I am not doing anything outside Australian law by implementing these
|
|
algorithms (to the best of my knowedge). It is another example of how
|
|
the world legal system does not cope with the internet very well.
|
|
|
|
I may start making shared libraries available (I have now got DLL's for
|
|
Windows). This will mean that distributions into the usa could be
|
|
shipped with a version with a reduced cipher set and the versions outside
|
|
could use the DLL/shared library with all the ciphers (and without RSAref).
|
|
|
|
This could be completly hidden from the application, so this would not
|
|
even require a re-linking.
|
|
|
|
This is the reverse of what people were talking about doing to get around
|
|
USA export regulations :-)
|
|
|
|
eric
|
|
|
|
[1]: The RSAref2.0 tookit is available on at least 3 ftp sites in Europe
|
|
and one in South Africa.
|
|
|
|
[2]: Since I always get questions when I post benchmark numbers :-),
|
|
DES performace figures are in 1000's of bytes per second in cbc
|
|
mode using an 8192 byte buffer. The pentium 100 was running Windows NT
|
|
3.51 DLLs and the 686/200 was running NextStep.
|
|
I quote pentium 100 benchmarks because it is basically the
|
|
'entry level' computer that most people buy for personal use.
|
|
Windows 95 is the OS shipping on those boxes, so I'll give
|
|
NT numbers (the same Win32 runtime environment). The 686
|
|
numbers are present as an indication of where we will be in a
|
|
few years.
|
|
--
|
|
Eric Young | BOOL is tri-state according to Bill Gates.
|
|
AARNet: eay@mincom.oz.au | RTFM Win32 GetMessage().
|
|
|
|
|
|
|
|
==== lhash.doc ========================================================
|
|
|
|
The LHASH library.
|
|
|
|
I wrote this library in 1991 and have since forgotten why I called it lhash.
|
|
It implements a hash table from an article I read at the
|
|
time from 'Communications of the ACM'. What makes this hash
|
|
table different is that as the table fills, the hash table is
|
|
increased (or decreased) in size via realloc().
|
|
When a 'resize' is done, instead of all hashes being redistributed over
|
|
twice as many 'buckets', one bucket is split. So when an 'expand' is done,
|
|
there is only a minimal cost to redistribute some values. Subsequent
|
|
inserts will cause more single 'bucket' redistributions but there will
|
|
never be a sudden large cost due to redistributing all the 'buckets'.
|
|
|
|
The state for a particular hash table is kept in the LHASH structure.
|
|
The LHASH structure also records statistics about most aspects of accessing
|
|
the hash table. This is mostly a legacy of my writing this library for
|
|
the reasons of implementing what looked like a nice algorithm rather than
|
|
for a particular software product.
|
|
|
|
Internal stuff you probably don't want to know about.
|
|
The decision to increase or decrease the hash table size is made depending
|
|
on the 'load' of the hash table. The load is the number of items in the
|
|
hash table divided by the size of the hash table. The default values are
|
|
as follows. If (hash->up_load < load) => expand.
|
|
if (hash->down_load > load) => contract. The 'up_load' has a default value of
|
|
1 and 'down_load' has a default value of 2. These numbers can be modified
|
|
by the application by just playing with the 'up_load' and 'down_load'
|
|
variables. The 'load' is kept in a form which is multiplied by 256. So
|
|
hash->up_load=8*256; will cause a load of 8 to be set.
|
|
|
|
If you are interested in performance the field to watch is
|
|
num_comp_calls. The hash library keeps track of the 'hash' value for
|
|
each item so when a lookup is done, the 'hashes' are compared, if
|
|
there is a match, then a full compare is done, and
|
|
hash->num_comp_calls is incremented. If num_comp_calls is not equal
|
|
to num_delete plus num_retrieve it means that your hash function is
|
|
generating hashes that are the same for different values. It is
|
|
probably worth changing your hash function if this is the case because
|
|
even if your hash table has 10 items in a 'bucked', it can be searched
|
|
with 10 'unsigned long' compares and 10 linked list traverses. This
|
|
will be much less expensive that 10 calls to you compare function.
|
|
|
|
LHASH *lh_new(
|
|
unsigned long (*hash)(),
|
|
int (*cmp)());
|
|
This function is used to create a new LHASH structure. It is passed
|
|
function pointers that are used to store and retrieve values passed
|
|
into the hash table. The 'hash'
|
|
function is a hashing function that will return a hashed value of
|
|
it's passed structure. 'cmp' is passed 2 parameters, it returns 0
|
|
is they are equal, otherwise, non zero.
|
|
If there are any problems (usually malloc failures), NULL is
|
|
returned, otherwise a new LHASH structure is returned. The
|
|
hash value is normally truncated to a power of 2, so make sure
|
|
that your hash function returns well mixed low order bits.
|
|
|
|
void lh_free(
|
|
LHASH *lh);
|
|
This function free()s a LHASH structure. If there is malloced
|
|
data in the hash table, it will not be freed. Consider using the
|
|
lh_doall function to deallocate any remaining entries in the hash
|
|
table.
|
|
|
|
char *lh_insert(
|
|
LHASH *lh,
|
|
char *data);
|
|
This function inserts the data pointed to by data into the lh hash
|
|
table. If there is already and entry in the hash table entry, the
|
|
value being replaced is returned. A NULL is returned if the new
|
|
entry does not clash with an entry already in the table (the normal
|
|
case) or on a malloc() failure (perhaps I should change this....).
|
|
The 'char *data' is exactly what is passed to the hash and
|
|
comparison functions specified in lh_new().
|
|
|
|
char *lh_delete(
|
|
LHASH *lh,
|
|
char *data);
|
|
This routine deletes an entry from the hash table. The value being
|
|
deleted is returned. NULL is returned if there is no such value in
|
|
the hash table.
|
|
|
|
char *lh_retrieve(
|
|
LHASH *lh,
|
|
char *data);
|
|
If 'data' is in the hash table it is returned, else NULL is
|
|
returned. The way these routines would normally be uses is that a
|
|
dummy structure would have key fields populated and then
|
|
ret=lh_retrieve(hash,&dummy);. Ret would now be a pointer to a fully
|
|
populated structure.
|
|
|
|
void lh_doall(
|
|
LHASH *lh,
|
|
void (*func)(char *a));
|
|
This function will, for every entry in the hash table, call function
|
|
'func' with the data item as parameters.
|
|
This function can be quite useful when used as follows.
|
|
void cleanup(STUFF *a)
|
|
{ STUFF_free(a); }
|
|
lh_doall(hash,cleanup);
|
|
lh_free(hash);
|
|
This can be used to free all the entries, lh_free() then
|
|
cleans up the 'buckets' that point to nothing. Be careful
|
|
when doing this. If you delete entries from the hash table,
|
|
in the call back function, the table may decrease in size,
|
|
moving item that you are
|
|
currently on down lower in the hash table. This could cause
|
|
some entries to be skipped. The best solution to this problem
|
|
is to set lh->down_load=0 before you start. This will stop
|
|
the hash table ever being decreased in size.
|
|
|
|
void lh_doall_arg(
|
|
LHASH *lh;
|
|
void(*func)(char *a,char *arg));
|
|
char *arg;
|
|
This function is the same as lh_doall except that the function
|
|
called will be passed 'arg' as the second argument.
|
|
|
|
unsigned long lh_strhash(
|
|
char *c);
|
|
This function is a demo string hashing function. Since the LHASH
|
|
routines would normally be passed structures, this routine would
|
|
not normally be passed to lh_new(), rather it would be used in the
|
|
function passed to lh_new().
|
|
|
|
The next three routines print out various statistics about the state of the
|
|
passed hash table. These numbers are all kept in the lhash structure.
|
|
|
|
void lh_stats(
|
|
LHASH *lh,
|
|
FILE *out);
|
|
This function prints out statistics on the size of the hash table,
|
|
how many entries are in it, and the number and result of calls to
|
|
the routines in this library.
|
|
|
|
void lh_node_stats(
|
|
LHASH *lh,
|
|
FILE *out);
|
|
For each 'bucket' in the hash table, the number of entries is
|
|
printed.
|
|
|
|
void lh_node_usage_stats(
|
|
LHASH *lh,
|
|
FILE *out);
|
|
This function prints out a short summary of the state of the hash
|
|
table. It prints what I call the 'load' and the 'actual load'.
|
|
The load is the average number of data items per 'bucket' in the
|
|
hash table. The 'actual load' is the average number of items per
|
|
'bucket', but only for buckets which contain entries. So the
|
|
'actual load' is the average number of searches that will need to
|
|
find an item in the hash table, while the 'load' is the average number
|
|
that will be done to record a miss.
|
|
|
|
==== md2.doc ========================================================
|
|
|
|
The MD2 library.
|
|
MD2 is a message digest algorithm that can be used to condense an arbitrary
|
|
length message down to a 16 byte hash. The functions all need to be passed
|
|
a MD2_CTX which is used to hold the MD2 context during multiple MD2_Update()
|
|
function calls. The normal method of use for this library is as follows
|
|
|
|
MD2_Init(...);
|
|
MD2_Update(...);
|
|
...
|
|
MD2_Update(...);
|
|
MD2_Final(...);
|
|
|
|
This library requires the inclusion of 'md2.h'.
|
|
|
|
The main negative about MD2 is that it is slow, especially when compared
|
|
to MD5.
|
|
|
|
The functions are as follows:
|
|
|
|
void MD2_Init(
|
|
MD2_CTX *c);
|
|
This function needs to be called to initiate a MD2_CTX structure for
|
|
use.
|
|
|
|
void MD2_Update(
|
|
MD2_CTX *c;
|
|
unsigned char *data;
|
|
unsigned long len);
|
|
This updates the message digest context being generated with 'len'
|
|
bytes from the 'data' pointer. The number of bytes can be any
|
|
length.
|
|
|
|
void MD2_Final(
|
|
unsigned char *md;
|
|
MD2_CTX *c;
|
|
This function is called when a message digest of the data digested
|
|
with MD2_Update() is wanted. The message digest is put in the 'md'
|
|
array and is MD2_DIGEST_LENGTH (16) bytes long.
|
|
|
|
unsigned char *MD2(
|
|
unsigned long n;
|
|
unsigned char *d;
|
|
unsigned char *md;
|
|
This function performs a MD2_Init(), followed by a MD2_Update()
|
|
followed by a MD2_Final() (using a local MD2_CTX).
|
|
The resulting digest is put into 'md' if it is not NULL.
|
|
Regardless of the value of 'md', the message
|
|
digest is returned from the function. If 'md' was NULL, the message
|
|
digest returned is being stored in a static structure.
|
|
|
|
==== md5.doc ========================================================
|
|
|
|
The MD5 library.
|
|
MD5 is a message digest algorithm that can be used to condense an arbitrary
|
|
length message down to a 16 byte hash. The functions all need to be passed
|
|
a MD5_CTX which is used to hold the MD5 context during multiple MD5_Update()
|
|
function calls. This library also contains random number routines that are
|
|
based on MD5
|
|
|
|
The normal method of use for this library is as follows
|
|
|
|
MD5_Init(...);
|
|
MD5_Update(...);
|
|
...
|
|
MD5_Update(...);
|
|
MD5_Final(...);
|
|
|
|
This library requires the inclusion of 'md5.h'.
|
|
|
|
The functions are as follows:
|
|
|
|
void MD5_Init(
|
|
MD5_CTX *c);
|
|
This function needs to be called to initiate a MD5_CTX structure for
|
|
use.
|
|
|
|
void MD5_Update(
|
|
MD5_CTX *c;
|
|
unsigned char *data;
|
|
unsigned long len);
|
|
This updates the message digest context being generated with 'len'
|
|
bytes from the 'data' pointer. The number of bytes can be any
|
|
length.
|
|
|
|
void MD5_Final(
|
|
unsigned char *md;
|
|
MD5_CTX *c;
|
|
This function is called when a message digest of the data digested
|
|
with MD5_Update() is wanted. The message digest is put in the 'md'
|
|
array and is MD5_DIGEST_LENGTH (16) bytes long.
|
|
|
|
unsigned char *MD5(
|
|
unsigned char *d;
|
|
unsigned long n;
|
|
unsigned char *md;
|
|
This function performs a MD5_Init(), followed by a MD5_Update()
|
|
followed by a MD5_Final() (using a local MD5_CTX).
|
|
The resulting digest is put into 'md' if it is not NULL.
|
|
Regardless of the value of 'md', the message
|
|
digest is returned from the function. If 'md' was NULL, the message
|
|
digest returned is being stored in a static structure.
|
|
|
|
|
|
==== memory.doc ========================================================
|
|
|
|
In the interests of debugging SSLeay, there is an option to compile
|
|
using some simple memory leak checking.
|
|
|
|
All malloc(), free() and realloc() calls in SSLeay now go via
|
|
Malloc(), Free() and Realloc() (except those in crypto/lhash).
|
|
|
|
If CRYPTO_MDEBUG is defined, these calls are #defined to
|
|
CRYPTO_malloc(), CRYPTO_free() and CRYPTO_realloc().
|
|
If it is not defined, they are #defined to malloc(), free() and realloc().
|
|
|
|
the CRYPTO_malloc() routines by default just call the underlying library
|
|
functons.
|
|
|
|
If CRYPTO_mem_ctrl(CRYPTO_MEM_CHECK_ON) is called, memory leak detection is
|
|
turned on. CRYPTO_mem_ctrl(CRYPTO_MEM_CHECK_OFF) turns it off.
|
|
|
|
When turned on, each Malloc() or Realloc() call is recored along with the file
|
|
and line number from where the call was made. (This is done using the
|
|
lhash library which always uses normal system malloc(3) routines).
|
|
|
|
void CRYPTO_mem_leaks(BIO *b);
|
|
void CRYPTO_mem_leaks_fp(FILE *fp);
|
|
These both print out the list of memory that has not been free()ed.
|
|
This will probably be rather hard to read, but if you look for the 'top level'
|
|
structure allocation, this will often give an idea as to what is not being
|
|
free()ed. I don't expect people to use this stuff normally.
|
|
|
|
==== ca.1 ========================================================
|
|
|
|
From eay@orb.mincom.oz.au Thu Dec 28 23:56:45 1995
|
|
Received: by orb.mincom.oz.au id AA07374
|
|
(5.65c/IDA-1.4.4 for eay); Thu, 28 Dec 1995 13:56:45 +1000
|
|
Date: Thu, 28 Dec 1995 13:56:45 +1000 (EST)
|
|
From: Eric Young <eay@mincom.oz.au>
|
|
X-Sender: eay@orb
|
|
To: sameer <sameer@c2.org>
|
|
Cc: ssleay@mincom.oz.au
|
|
Subject: Re: 'ca'
|
|
In-Reply-To: <199512230440.UAA23410@infinity.c2.org>
|
|
Message-Id: <Pine.SOL.3.91.951228133525.7269A-100000@orb>
|
|
Mime-Version: 1.0
|
|
Content-Type: TEXT/PLAIN; charset=US-ASCII
|
|
Status: RO
|
|
X-Status:
|
|
|
|
On Fri, 22 Dec 1995, sameer wrote:
|
|
> I could use documentation on 'ca'. Thanks.
|
|
|
|
Very quickly.
|
|
The ca program uses the ssleay.conf file for most of its configuration
|
|
|
|
./ca -help
|
|
|
|
-verbose - Talk alot while doing things
|
|
-config file - A config file. If you don't want to use the
|
|
default config file
|
|
-name arg - The particular CA definition to use
|
|
In the config file, the section to use for parameters. This lets
|
|
multiple setups to be contained in the one file. By default, the
|
|
default_ca variable is looked up in the [ ca ] section. So in the
|
|
shipped ssleay.conf, the CA definition used is CA_default. It could be
|
|
any other name.
|
|
-gencrl days - Generate a new CRL, days is when the next CRL is due
|
|
This will generate a new certificate revocion list.
|
|
-days arg - number of days to certify the certificate for
|
|
When certifiying certificates, this is the number of days to use.
|
|
-md arg - md to use, one of md2, md5, sha or sha1
|
|
-policy arg - The CA 'policy' to support
|
|
I'll describe this later, but there are 2 policies definied in the
|
|
shipped ssleay.conf
|
|
-keyfile arg - PEM RSA private key file
|
|
-key arg - key to decode the RSA private key if it is encrypted
|
|
since we need to keep the CA's RSA key encrypted
|
|
-cert - The CA certificate
|
|
-in file - The input PEM encoded certificate request(s)
|
|
-out file - Where to put the output file(s)
|
|
-outdir dir - Where to put output certificates
|
|
The -out options concatinates all the output certificied
|
|
certificates to one file, -outdir puts them in a directory,
|
|
named by serial number.
|
|
-infiles .... - The last argument, requests to process
|
|
The certificate requests to process, -in is the same.
|
|
|
|
Just about all the above have default values defined in ssleay.conf.
|
|
|
|
The key variables in ssleay.conf are (for the pariticular '-name' being
|
|
used, in the default, it is CA_default).
|
|
|
|
dir is where all the CA database stuff is kept.
|
|
certs is where all the previously issued certificates are kept.
|
|
The database is a simple text database containing the following tab separated
|
|
fields.
|
|
status: a value of 'R' - revoked, 'E' -expired or 'V' valid.
|
|
issued date: When the certificate was certified.
|
|
revoked date: When it was revoked, blank if not revoked.
|
|
serial number: The certificate serial number.
|
|
certificate: Where the certificate is located.
|
|
CN: The name of the certificate.
|
|
|
|
The demo file has quite a few made up values it it. The last 2 were
|
|
added by the ca program and are acurate.
|
|
The CA program does not update the 'certificate' file correctly right now.
|
|
The serial field should be unique as should the CN/status combination.
|
|
The ca program checks these at startup. What still needs to be
|
|
wrtten is a program to 'regenerate' the data base file from the issued
|
|
certificate list (and a CRL list).
|
|
|
|
Back to the CA_default variables.
|
|
|
|
Most of the variables are commented.
|
|
|
|
policy is the default policy.
|
|
|
|
Ok for policies, they define the order and which fields must be present
|
|
in the certificate request and what gets filled in.
|
|
|
|
So a value of
|
|
countryName = match
|
|
means that the country name must match the CA certificate.
|
|
organizationalUnitName = optional
|
|
The org.Unit,Name does not have to be present and
|
|
commonName = supplied
|
|
commonName must be supplied in the certificate request.
|
|
|
|
For the 'policy_match' polocy, the order of the attributes in the
|
|
generated certiticate would be
|
|
countryName
|
|
stateOrProvinceName
|
|
organizationName
|
|
organizationalUnitName
|
|
commonName
|
|
emailAddress
|
|
|
|
Have a play, it sort of makes sense. If you think about how the persona
|
|
requests operate, it is similar to the 'policy_match' policy and the
|
|
'policy_anything' is similar to what versign is doing.
|
|
|
|
I hope this helps a bit. Some backend scripts are definitly needed to
|
|
update the database and to make certificate revocion easy. All
|
|
certificates issued should also be kept forever (or until they expire?)
|
|
|
|
hope this helps
|
|
eric (who has to run off an buy some cheap knee pads for the caving in 4
|
|
days time :-)
|
|
|
|
--
|
|
Eric Young | Signature removed since it was generating
|
|
AARNet: eay@mincom.oz.au | more followups than the message contents :-)
|
|
|
|
|
|
==== ms3-ca.doc ========================================================
|
|
|
|
Date: Mon, 9 Jun 97 08:00:33 +0200
|
|
From: Holger.Reif@PrakInf.TU-Ilmenau.DE (Holger Reif)
|
|
Subject: ms3-ca.doc
|
|
Organization: TU Ilmenau, Fak. IA, FG Telematik
|
|
Content-Length: 14575
|
|
Status: RO
|
|
X-Status:
|
|
|
|
Loading client certs into MSIE 3.01
|
|
===================================
|
|
|
|
This document conatains all the information necessary to succesfully set up
|
|
some scripts to issue client certs to Microsoft Internet Explorer. It
|
|
includes the required knowledge about the model MSIE uses for client
|
|
certification and includes complete sample scripts ready to play with. The
|
|
scripts were tested against a modified ca program of SSLeay 0.6.6 and should
|
|
work with the regular ca program that comes with version 0.8.0. I haven't
|
|
tested against MSIE 4.0
|
|
|
|
You can use the information contained in this document in either way you
|
|
want. However if you feel it saved you a lot of time I ask you to be as fair
|
|
as to mention my name: Holger Reif <reif@prakinf.tu-ilmenau.de>.
|
|
|
|
1.) The model used by MSIE
|
|
--------------------------
|
|
|
|
The Internet Explorer doesn't come with a embedded engine for installing
|
|
client certs like Netscape's Navigator. It rather uses the CryptoAPI (CAPI)
|
|
defined by Microsoft. CAPI comes with WindowsNT 4.0 or is installed together
|
|
with Internet Explorer since 3.01. The advantage of this approach is a higher
|
|
flexibility because the certificates in the (per user) system open
|
|
certificate store may be used by other applications as well. The drawback
|
|
however is that you need to do a bit more work to get a client cert issued.
|
|
|
|
CAPI defines functions which will handle basic cryptographic work, eg.
|
|
generating keys, encrypting some data, signing text or building a certificate
|
|
request. The procedure is as follows: A CAPI function generates you a key
|
|
pair and saves it into the certificate store. After that one builds a
|
|
Distinguished Name. Together with that key pair another CAPI function forms a
|
|
PKCS#10 request which you somehow need to submit to a CA. Finally the issued
|
|
cert is given to a yet another CAPI function which saves it into the
|
|
certificate store.
|
|
|
|
The certificate store with the user's keys and certs is in the registry. You
|
|
will find it under HKEY_CURRENT_USER/Software/Microsoft/Cryptography/ (I
|
|
leave it to you as a little exercise to figure out what all the entries mean
|
|
;-). Note that the keys are protected only with the user's usual Windows
|
|
login password.
|
|
|
|
2.) The practical usage
|
|
-----------------------
|
|
|
|
Unfortunatly since CAPI is a system API you can't access its functions from
|
|
HTML code directly. For this purpose Microsoft provides a wrapper called
|
|
certenr3.dll. This DLL accesses the CAPI functions and provides an interface
|
|
usable from Visual Basic Script. One needs to install that library on the
|
|
computer which wants to have client cert. The easiest way is to load it as an
|
|
ActiveX control (certenr3.dll is properly authenticode signed by MS ;-). If
|
|
you have ever enrolled e cert request at a CA you will have installed it.
|
|
|
|
At time of writing certenr3.dll is contained in
|
|
http://www.microsoft.com/workshop/prog/security/csa/certenr3.exe. It comes
|
|
with an README file which explains the available functions. It is labeled
|
|
beta but every CA seems to use it anyway. The license.txt allows you the
|
|
usage for your own purposes (as far as I understood) and a somehow limited
|
|
distribution.
|
|
|
|
The two functions of main interest are GenerateKeyPair and AcceptCredentials.
|
|
For complete explanation of all possible parameters see the README file. Here
|
|
are only minimal required parameters and their values.
|
|
|
|
GenerateKeyPair(sessionID, FASLE, szName, 0, "ClientAuth", TRUE, FALSE, 1)
|
|
- sessionID is a (locally to that computer) unique string to correlate the
|
|
generated key pair with a cert installed later.
|
|
- szName is the DN of the form "C=DE; S=Thueringen; L=Ilmenau; CN=Holger
|
|
Reif; 1.2.840.113549.1.9.1=reif@prakinf.tu-ilmenau.de". Note that S is the
|
|
abreviation for StateOrProvince. The recognized abreviation include CN, O, C,
|
|
OU, G, I, L, S, T. If the abreviation is unknown (eg. for PKCS#9 email addr)
|
|
you need to use the full object identifier. The starting point for searching
|
|
them could be crypto/objects.h since all OIDs know to SSLeay are listed
|
|
there.
|
|
- note: the possible ninth parameter which should give a default name to the
|
|
certificate storage location doesn't seem to work. Changes to the constant
|
|
values in the call above doesn't seem to make sense. You can't generate
|
|
PKCS#10 extensions with that function.
|
|
|
|
The result of GenerateKeyPair is the base64 encoded PKCS#10 request. However
|
|
it has a little strange format that SSLeay doesn't accept. (BTW I feel the
|
|
decision of rejecting that format as standard conforming.) It looks like
|
|
follows:
|
|
1st line with 76 chars
|
|
2nd line with 76 chars
|
|
...
|
|
(n-2)th line with 76 chars
|
|
(n-1)th line contains a multiple of 4 chars less then 76 (possible
|
|
empty)
|
|
(n)th line has zero or 4 chars (then with 1 or 2 equal signs - the
|
|
original text's lenght wasn'T a multiple of 3)
|
|
The line separator has two chars: 0x0d 0x0a
|
|
|
|
AcceptCredentials(sessionID, credentials, 0, FALSE)
|
|
- sessionID needs to be the same as while generating the key pair
|
|
- credentials is the base64 encoded PKCS#7 object containing the cert.
|
|
|
|
CRL's and CA certs are not required simply just the client cert. (It seems to
|
|
me that both are not even checked somehow.) The only format of the base64
|
|
encoded object I succesfully used was all characters in a very long string
|
|
without line feeds or carriage returns. (Hey, it doesn't matter, only a
|
|
computer reads it!)
|
|
|
|
The result should be S_OK. For error handling see the example that comes with
|
|
certenr3.dll.
|
|
|
|
A note about ASN.1 character encodings. certenr3.dll seems to know only about
|
|
2 of them: UniversalString and PrintableString. First it is definitely wrong
|
|
for an email address which is IA5STRING (checked by ssleay's ca). Second
|
|
unfortunately MSIE (at least until version 3.02) can't handle UniversalString
|
|
correctly - they just blow up you cert store! Therefore ssleay's ca (starting
|
|
from version 0.8.0) tries to convert the encodings automatically to IA5STRING
|
|
or TeletexString. The beef is it will work only for the latin-1 (western)
|
|
charset. Microsoft still has to do abit of homework...
|
|
|
|
3.) An example
|
|
--------------
|
|
|
|
At least you need two steps: generating the key & request and then installing
|
|
the certificate. A real world CA would have some more steps involved, eg.
|
|
accepting some license. Note that both scripts shown below are just
|
|
experimental state without any warrenty!
|
|
|
|
First how to generate a request. Note that we can't use a static page because
|
|
of the sessionID. I generate it from system time plus pid and hope it is
|
|
unique enough. Your are free to feed it through md5 to get more impressive
|
|
ID's ;-) Then the intended text is read in with sed which inserts the
|
|
sessionID.
|
|
|
|
-----BEGIN ms-enroll.cgi-----
|
|
#!/bin/sh
|
|
SESSION_ID=`date '+%y%m%d%H%M%S'`$$
|
|
echo Content-type: text/html
|
|
echo
|
|
sed s/template_for_sessId/$SESSION_ID/ <<EOF
|
|
<HTML><HEAD>
|
|
<TITLE>Certificate Enrollment Test Page</TITLE>
|
|
</HEAD><BODY>
|
|
|
|
<OBJECT
|
|
classid="clsid:33BEC9E0-F78F-11cf-B782-00C04FD7BF43"
|
|
codebase=certenr3.dll
|
|
id=certHelper
|
|
>
|
|
</OBJECT>
|
|
|
|
<CENTER>
|
|
<H2>enrollment for a personal cert</H2>
|
|
<BR><HR WIDTH=50%><BR><P>
|
|
<FORM NAME="MSIE_Enrollment" ACTION="ms-gencert.cgi" ENCTYPE=x-www-form-
|
|
encoded METHOD=POST>
|
|
<TABLE>
|
|
<TR><TD>Country</TD><TD><INPUT NAME="Country" VALUE=""></TD></TR>
|
|
<TR><TD>State</TD><TD><INPUT NAME="StateOrProvince" VALUE=""></TD></TR>
|
|
<TR><TD>Location</TD><TD><INPUT NAME="Location" VALUE=""></TD></TR>
|
|
<TR><TD>Organization</TD><TD><INPUT NAME="Organization"
|
|
VALUE=""></TD></TR>
|
|
<TR><TD>Organizational Unit</TD>
|
|
<TD><INPUT NAME="OrganizationalUnit" VALUE=""></TD></TR>
|
|
<TR><TD>Name</TD><TD><INPUT NAME="CommonName" VALUE=""></TD></TR>
|
|
<TR><TD>eMail Address</TD>
|
|
<TD><INPUT NAME="EmailAddress" VALUE=""></TD></TR>
|
|
<TR><TD></TD>
|
|
<TD><INPUT TYPE="BUTTON" NAME="submit" VALUE="Beantragen"></TD></TR>
|
|
</TABLE>
|
|
<INPUT TYPE="hidden" NAME="SessionId" VALUE="template_for_sessId">
|
|
<INPUT TYPE="hidden" NAME="Request" VALUE="">
|
|
</FORM>
|
|
<BR><HR WIDTH=50%><BR><P>
|
|
</CENTER>
|
|
|
|
<SCRIPT LANGUAGE=VBS>
|
|
Dim DN
|
|
|
|
Sub Submit_OnClick
|
|
Dim TheForm
|
|
Set TheForm = Document.MSIE_Enrollment
|
|
sessionId = TheForm.SessionId.value
|
|
reqHardware = FALSE
|
|
C = TheForm.Country.value
|
|
SP = TheForm.StateOrProvince.value
|
|
L = TheForm.Location.value
|
|
O = TheForm.Organization.value
|
|
OU = TheForm.OrganizationalUnit.value
|
|
CN = TheForm.CommonName.value
|
|
Email = TheForm.EmailAddress.value
|
|
szPurpose = "ClientAuth"
|
|
doAcceptanceUINow = FALSE
|
|
doOnline = TRUE
|
|
|
|
DN = ""
|
|
|
|
Call Add_RDN("C", C)
|
|
Call Add_RDN("S", SP)
|
|
Call Add_RDN("L", L)
|
|
Call Add_RDN("O", O)
|
|
Call Add_RDN("OU", OU)
|
|
Call Add_RDN("CN", CN)
|
|
Call Add_RDN("1.2.840.113549.1.9.1", Email)
|
|
' rsadsi
|
|
' pkcs
|
|
' pkcs9
|
|
' eMailAddress
|
|
On Error Resume Next
|
|
sz10 = certHelper.GenerateKeyPair(sessionId, _
|
|
FALSE, DN, 0, ClientAuth, FASLE, TRUE, 1)_
|
|
theError = Err.Number
|
|
On Error Goto 0
|
|
if (sz10 = Empty OR theError <> 0) Then
|
|
sz = "The error '" & Hex(theError) & "' occurred." & chr(13) & _
|
|
chr(10) & "Your credentials could not be generated."
|
|
result = MsgBox(sz, 0, "Credentials Enrollment")
|
|
Exit Sub
|
|
else
|
|
TheForm.Request.value = sz10
|
|
TheForm.Submit
|
|
end if
|
|
End Sub
|
|
|
|
Sub Add_RDN(sn, value)
|
|
if (value <> "") then
|
|
if (DN <> "") then
|
|
DN = DN & "; "
|
|
end if
|
|
DN = DN & sn & "=" & value
|
|
end if
|
|
End Sub
|
|
</SCRIPT>
|
|
</BODY>
|
|
</HTML>
|
|
EOF
|
|
-----END ms-enroll.cgi-----
|
|
|
|
Second, how to extract the request and feed the certificate back? We need to
|
|
"normalize" the base64 encoding of the PKCS#10 format which means
|
|
regenerating the lines and wrapping with BEGIN and END line. This is done by
|
|
gawk. The request is taken by ca the normal way. Then the cert needs to be
|
|
packed into a PKCS#7 structure (note: the use of a CRL is necessary for
|
|
crl2pkcs7 as of version 0.6.6. Starting with 0.8.0 it it might probably be
|
|
ommited). Finally we need to format the PKCS#7 object and generate the HTML
|
|
text. I use two templates to have a clearer script.
|
|
|
|
1st note: postit2 is slightly modified from a program I found at ncsa's ftp
|
|
site. Grab it from http://www.easterngraphics.com/certs/IX9704/postit2.c. You
|
|
need utils.c from there too.
|
|
|
|
2nd note: I'm note quite sure wether the gawk script really handles all
|
|
possible inputs for the request right! Today I don't use this construction
|
|
anymore myself.
|
|
|
|
3d note: the cert must be of version 3! This could be done with the nsComment
|
|
line in ssleay.cnf...
|
|
|
|
------BEGIN ms-gencert.cgi-----
|
|
#!/bin/sh
|
|
FILE="/tmp/"`date '+%y%m%d%H%M%S'-`$$
|
|
rm -f "$FILE".*
|
|
|
|
HOME=`pwd`; export HOME # as ssleay.cnf insists on having such an env var
|
|
cd /usr/local/ssl #where demoCA (as named in ssleay.conf) is located
|
|
|
|
postit2 -s " " -i 0x0d > "$FILE".inp # process the FORM vars
|
|
|
|
SESSION_ID=`gawk '$1 == "SessionId" { print $2; exit }' "$FILE".inp`
|
|
|
|
gawk \
|
|
'BEGIN { \
|
|
OFS = ""; \
|
|
print "-----BEGIN CERTIFICATE REQUEST-----"; \
|
|
req_seen=0 \
|
|
} \
|
|
$1 == "Request" { \
|
|
req_seen=1; \
|
|
if (length($2) == 72) print($2); \
|
|
lastline=$2; \
|
|
next; \
|
|
} \
|
|
{ \
|
|
if (req_seen == 1) { \
|
|
if (length($1) >= 72) print($1); \
|
|
else if (length(lastline) < 72) { \
|
|
req_seen=0; \
|
|
print (lastline,$1); \
|
|
} \
|
|
lastline=$1; \
|
|
} \
|
|
} \
|
|
END { \
|
|
print "-----END CERTIFICATE REQUEST-----"; \
|
|
}' > "$FILE".pem < "$FILE".inp
|
|
|
|
ssleay ca -batch -in "$FILE".pem -key passwd -out "$FILE".out
|
|
ssleay crl2pkcs7 -certfile "$FILE".out -out "$FILE".pkcs7 -in demoCA/crl.pem
|
|
|
|
sed s/template_for_sessId/$SESSION_ID/ <ms-enroll2a.html >"$FILE".cert
|
|
/usr/local/bin/gawk \
|
|
'BEGIN { \
|
|
OFS = ""; \
|
|
dq = sprintf("%c",34); \
|
|
} \
|
|
$0 ~ "PKCS7" { next; } \
|
|
{ \
|
|
print dq$0dq" & _"; \
|
|
}' <"$FILE".pkcs7 >> "$FILE".cert
|
|
cat ms-enroll2b.html >>"$FILE".cert
|
|
|
|
echo Content-type: text/html
|
|
echo Content-length: `wc -c "$FILE".cert`
|
|
echo
|
|
cat "$FILE".cert
|
|
rm -f "$FILE".*
|
|
-----END ms-gencert.cgi-----
|
|
|
|
----BEGIN ms-enroll2a.html----
|
|
<HTML><HEAD><TITLE>Certificate Acceptance Test Page</TITLE></HEAD><BODY>
|
|
|
|
<OBJECT
|
|
classid="clsid:33BEC9E0-F78F-11cf-B782-00C04FD7BF43"
|
|
codebase=certenr3.dll
|
|
id=certHelper
|
|
>
|
|
</OBJECT>
|
|
|
|
<CENTER>
|
|
<H2>Your personal certificate</H2>
|
|
<BR><HR WIDTH=50%><BR><P>
|
|
Press the button!
|
|
<P><INPUT TYPE=BUTTON VALUE="Nimm mich!" NAME="InstallCert">
|
|
</CENTER>
|
|
<BR><HR WIDTH=50%><BR>
|
|
|
|
<SCRIPT LANGUAGE=VBS>
|
|
Sub InstallCert_OnClick
|
|
|
|
sessionId = "template_for_sessId"
|
|
credentials = "" & _
|
|
----END ms-enroll2a.html----
|
|
|
|
----BEGIN ms-enroll2b.html----
|
|
""
|
|
On Error Resume Next
|
|
result = certHelper.AcceptCredentials(sessionId, credentials, 0,
|
|
FALSE)
|
|
if (IsEmpty(result)) Then
|
|
sz = "The error '" & Err.Number & "' occurred." & chr(13) &
|
|
chr(10) & "This Digital ID could not be registered."
|
|
msgOut = MsgBox(sz, 0, "Credentials Registration Error")
|
|
navigate "error.html"
|
|
else
|
|
sz = "Digital ID successfully registered."
|
|
msgOut = MsgBox(sz, 0, "Credentials Registration")
|
|
navigate "success.html"
|
|
end if
|
|
Exit Sub
|
|
End Sub
|
|
</SCRIPT>
|
|
</BODY>
|
|
</HTML>
|
|
----END ms-enroll2b.html----
|
|
|
|
4.) What do do with the cert?
|
|
-----------------------------
|
|
|
|
The cert is visible (without restarting MSIE) under the following menu:
|
|
View->Options->Security->Personal certs. You can examine it's contents at
|
|
least partially.
|
|
|
|
To use it for client authentication you need to use SSL3.0 (fortunately
|
|
SSLeay supports it with 0.8.0). Furthermore MSIE is told to only supports a
|
|
kind of automatic selection of certs (I personally wasn't able to test it
|
|
myself). But there is a requirement that the issuer of the server cert and
|
|
the issuer of the client cert needs to be the same (according to a developer
|
|
from MS). Which means: you need may more then one cert to talk to all
|
|
servers...
|
|
|
|
I'm sure we will get a bit more experience after ApacheSSL is available for
|
|
SSLeay 0.8.8.
|
|
|
|
|
|
I hope you enjoyed reading and that in future questions on this topic will
|
|
rarely appear on ssl-users@moncom.com ;-)
|
|
|
|
Ilmenau, 9th of June 1997
|
|
Holger Reif <reif@prakinf.tu-ilmenau.de>
|
|
--
|
|
read you later - Holger Reif
|
|
---------------------------------------- Signaturprojekt Deutsche Einheit
|
|
TU Ilmenau - Informatik - Telematik (Verdamp lang her)
|
|
Holger.Reif@PrakInf.TU-Ilmenau.DE Alt wie ein Baum werden, um ueber
|
|
http://Remus.PrakInf.TU-Ilmenau.DE/Reif/ alle 7 Bruecken gehen zu koennen
|
|
|
|
|
|
==== ns-ca.doc ========================================================
|
|
|
|
The following documentation was supplied by Jeff Barber, who provided the
|
|
patch to the CA program to add this functionality.
|
|
|
|
eric
|
|
--
|
|
Jeff Barber Email: jeffb@issl.atl.hp.com
|
|
|
|
Hewlett Packard Phone: (404) 648-9503
|
|
Internet and System Security Lab Fax: (404) 648-9516
|
|
|
|
oo
|
|
---------------------cut /\ here for ns-ca.doc ------------------------------
|
|
|
|
This document briefly describes how to use SSLeay to implement a
|
|
certificate authority capable of dynamically serving up client
|
|
certificates for version 3.0 beta 5 (and presumably later) versions of
|
|
the Netscape Navigator. Before describing how this is done, it's
|
|
important to understand a little about how the browser implements its
|
|
client certificate support. This is documented in some detail in the
|
|
URLs based at <URL:http://home.netscape.com/eng/security/certs.html>.
|
|
Here's a brief overview:
|
|
|
|
- The Navigator supports a new HTML tag "KEYGEN" which will cause
|
|
the browser to generate an RSA key pair when you submit a form
|
|
containing the tag. The public key, along with an optional
|
|
challenge (supposedly provided for use in certificate revocation
|
|
but I don't use it) is signed, DER-encoded, base-64 encoded
|
|
and sent to the web server as the value of the variable
|
|
whose NAME is provided in the KEYGEN tag. The private key is
|
|
stored by the browser in a local key database.
|
|
|
|
This "Signed Public Key And Challenge" (SPKAC) arrives formatted
|
|
into 64 character lines (which are of course URL-encoded when
|
|
sent via HTTP -- i.e. spaces, newlines and most punctuatation are
|
|
encoded as "%HH" where HH is the hex equivalent of the ASCII code).
|
|
Note that the SPKAC does not contain the other usual attributes
|
|
of a certificate request, especially the subject name fields.
|
|
These must be otherwise encoded in the form for submission along
|
|
with the SPKAC.
|
|
|
|
- Either immediately (in response to this form submission), or at
|
|
some later date (a real CA will probably verify your identity in
|
|
some way before issuing the certificate), a web server can send a
|
|
certificate based on the public key and other attributes back to
|
|
the browser by encoding it in DER (the binary form) and sending it
|
|
to the browser as MIME type:
|
|
"Content-type: application/x-x509-user-cert"
|
|
|
|
The browser uses the public key encoded in the certificate to
|
|
associate the certificate with the appropriate private key in
|
|
its local key database. Now, the certificate is "installed".
|
|
|
|
- When a server wants to require authentication based on client
|
|
certificates, it uses the right signals via the SSL protocol to
|
|
trigger the Navigator to ask you which certificate you want to
|
|
send. Whether the certificate is accepted is dependent on CA
|
|
certificates and so forth installed in the server and is beyond
|
|
the scope of this document.
|
|
|
|
|
|
Now, here's how the SSLeay package can be used to provide client
|
|
certficates:
|
|
|
|
- You prepare a file for input to the SSLeay ca application.
|
|
The file contains a number of "name = value" pairs that identify
|
|
the subject. The names here are the same subject name component
|
|
identifiers used in the CA section of the lib/ssleay.conf file,
|
|
such as "emailAddress", "commonName" "organizationName" and so
|
|
forth. Both the long version and the short version (e.g. "Email",
|
|
"CN", "O") can be used.
|
|
|
|
One more name is supported: this one is "SPKAC". Its value
|
|
is simply the value of the base-64 encoded SPKAC sent by the
|
|
browser (with all the newlines and other space charaters
|
|
removed -- and newline escapes are NOT supported).
|
|
|
|
[ As of SSLeay 0.6.4, multiple lines are supported.
|
|
Put a \ at the end of each line and it will be joined with the
|
|
previous line with the '\n' removed - eay ]
|
|
|
|
Here's a sample input file:
|
|
|
|
C = US
|
|
SP = Georgia
|
|
O = Some Organization, Inc.
|
|
OU = Netscape Compatibility Group
|
|
CN = John X. Doe
|
|
Email = jxdoe@someorg.com
|
|
SPKAC = MIG0MGAwXDANBgkqhkiG9w0BAQEFAANLADBIAkEAwmk6FMJ4uAVIYbcvIOx5+bDGTfvL8X5gE+R67ccMk6rCSGbVQz2cetyQtnI+VIs0NwdD6wjuSuVtVFbLoHonowIDAQABFgAwDQYJKoZIhvcNAQEEBQADQQBFZDUWFl6BJdomtN1Bi53mwijy1rRgJ4YirF15yBEDM3DjAQkKXHYOIX+qpz4KXKnl6EYxTnGSFL5wWt8X2iyx
|
|
|
|
- You execute the ca command (either from a CGI program run out of
|
|
the web server, or as a later manual task) giving it the above
|
|
file as input. For example, if the file were named /tmp/cert.req,
|
|
you'd run:
|
|
$SSLDIR/bin/ca -spkac /tmp/cert.req -out /tmp/cert
|
|
|
|
The output is in DER format (binary) if a -out argument is
|
|
provided, as above; otherwise, it's in the PEM format (base-64
|
|
encoded DER). Also, the "-batch" switch is implied by the
|
|
"-spkac" so you don't get asked whether to complete the signing
|
|
(probably it shouldn't work this way but I was only interested
|
|
in hacking together an online CA that could be used for issuing
|
|
test certificates).
|
|
|
|
The "-spkac" capability doesn't support multiple files (I think).
|
|
|
|
Any CHALLENGE provided in the SPKAC is simply ignored.
|
|
|
|
The interactions between the identification fields you provide
|
|
and those identified in your lib/ssleay.conf are the same as if
|
|
you did an ordinary "ca -in infile -out outfile" -- that is, if
|
|
something is marked as required in the ssleay.conf file and it
|
|
isn't found in the -spkac file, the certificate won't be issued.
|
|
|
|
- Now, you pick up the output from /tmp/cert and pass it back to
|
|
the Navigator prepending the Content-type string described earlier.
|
|
|
|
- In order to run the ca command out of a CGI program, you must
|
|
provide a password to decrypt the CA's private key. You can
|
|
do this by using "echo MyKeyPassword | $SSLDIR/bin/ca ..."
|
|
I think there's a way to not encrypt the key file in the first
|
|
place, but I didn't see how to do that, so I made a small change
|
|
to the library that allows the password to be accepted from a pipe.
|
|
Either way is UTTERLY INSECURE and a real CA would never do that.
|
|
|
|
[ You can use the 'ssleay rsa' command to remove the password
|
|
from the private key, or you can use the '-key' option to the
|
|
ca command to specify the decryption key on the command line
|
|
or use the -nodes option when generating the key.
|
|
ca will try to clear the command line version of the password
|
|
but for quite a few operating systems, this is not possible.
|
|
- eric ]
|
|
|
|
So, what do you have to do to make use of this stuff to create an online
|
|
demo CA capability with SSLeay?
|
|
|
|
1 Create an HTML form for your users. The form should contain
|
|
fields for all of the required or optional fields in ssleay.conf.
|
|
The form must contain a KEYGEN tag somewhere with at least a NAME
|
|
attribute.
|
|
|
|
2 Create a CGI program to process the form input submitted by the
|
|
browser. The CGI program must URL-decode the variables and create
|
|
the file described above, containing subject identification info
|
|
as well as the SPKAC block. It should then run the the ca program
|
|
with the -spkac option. If it works (check the exit status),
|
|
return the new certificate with the appropriate MIME type. If not,
|
|
return the output of the ca command with MIME type "text/plain".
|
|
|
|
3 Set up your web server to accept connections signed by your demo
|
|
CA. This probably involves obtaining the PEM-encoded CA certificate
|
|
(ordinarily in $SSLDIR/CA/cacert.pem) and installing it into a
|
|
server database. See your server manual for instructions.
|
|
|
|
|
|
==== obj.doc ========================================================
|
|
|
|
The Object library.
|
|
|
|
As part of my Crypto library, I found I required a method of identifying various
|
|
objects. These objects normally had 3 different values associated with
|
|
them, a short text name, a long (or lower case) text name, and an
|
|
ASN.1 Object Identifier (which is a sequence of numbers).
|
|
This library contains a static list of objects and functions to lookup
|
|
according to one type and to return the other types.
|
|
|
|
To use these routines, 'Object.h' needs to be included.
|
|
|
|
For each supported object, #define entries are defined as follows
|
|
#define SN_Algorithm "Algorithm"
|
|
#define LN_algorithm "algorithm"
|
|
#define NID_algorithm 38
|
|
#define OBJ_algorithm 1L,3L,14L,3L,2L
|
|
|
|
SN_ stands for short name.
|
|
LN_ stands for either long name or lowercase name.
|
|
NID_ stands for Numeric ID. I each object has a unique NID and this
|
|
should be used internally to identify objects.
|
|
OBJ_ stands for ASN.1 Object Identifier or ASN1_OBJECT as defined in the
|
|
ASN1 routines. These values are used in ASN1 encoding.
|
|
|
|
The following functions are to be used to return pointers into a static
|
|
definition of these types. What this means is "don't try to free() any
|
|
pointers returned from these functions.
|
|
|
|
ASN1_OBJECT *OBJ_nid2obj(
|
|
int n);
|
|
Return the ASN1_OBJECT that corresponds to a NID of n.
|
|
|
|
char *OBJ_nid2ln(
|
|
int n);
|
|
Return the long/lower case name of the object represented by the
|
|
NID of n.
|
|
|
|
char *OBJ_nid2sn(
|
|
int n);
|
|
Return the short name for the object represented by the NID of n.
|
|
|
|
ASN1_OBJECT *OBJ_dup(
|
|
ASN1_OBJECT *o);
|
|
Duplicate and return a new ASN1_OBJECT that is the same as the
|
|
passed parameter.
|
|
|
|
int OBJ_obj2nid(
|
|
ASN1_OBJECT *o);
|
|
Given ASN1_OBJECT o, return the NID that corresponds.
|
|
|
|
int OBJ_ln2nid(
|
|
char *s);
|
|
Given the long/lower case name 's', return the NID of the object.
|
|
|
|
int OBJ_sn2nid(
|
|
char *s);
|
|
Given the short name 's', return the NID of the object.
|
|
|
|
char *OBJ_bsearch(
|
|
char *key,
|
|
char *base,
|
|
int num,
|
|
int size,
|
|
int (*cmp)());
|
|
Since I have come across a few platforms that do not have the
|
|
bsearch() function, OBJ_bsearch is my version of that function.
|
|
Feel free to use this function, but you may as well just use the
|
|
normal system bsearch(3) if it is present. This version also
|
|
has tolerance of being passed NULL pointers.
|
|
|
|
==== keys ===========================================================
|
|
|
|
EVP_PKEY_DSA
|
|
EVP_PKEY_DSA2
|
|
EVP_PKEY_DSA3
|
|
EVP_PKEY_DSA4
|
|
|
|
EVP_PKEY_RSA
|
|
EVP_PKEY_RSA2
|
|
|
|
valid DSA pkey types
|
|
NID_dsa
|
|
NID_dsaWithSHA
|
|
NID_dsaWithSHA1
|
|
NID_dsaWithSHA1_2
|
|
|
|
valid RSA pkey types
|
|
NID_rsaEncryption
|
|
NID_rsa
|
|
|
|
NID_dsaWithSHA NID_dsaWithSHA DSA SHA
|
|
NID_dsa NID_dsaWithSHA1 DSA SHA1
|
|
NID_md2 NID_md2WithRSAEncryption RSA-pkcs1 MD2
|
|
NID_md5 NID_md5WithRSAEncryption RSA-pkcs1 MD5
|
|
NID_mdc2 NID_mdc2WithRSA RSA-none MDC2
|
|
NID_ripemd160 NID_ripemd160WithRSA RSA-pkcs1 RIPEMD160
|
|
NID_sha NID_shaWithRSAEncryption RSA-pkcs1 SHA
|
|
NID_sha1 NID_sha1WithRSAEncryption RSA-pkcs1 SHA1
|
|
|
|
==== rand.doc ========================================================
|
|
|
|
My Random number library.
|
|
|
|
These routines can be used to generate pseudo random numbers and can be
|
|
used to 'seed' the pseudo random number generator (RNG). The RNG make no
|
|
effort to reproduce the same random number stream with each execution.
|
|
Various other routines in the SSLeay library 'seed' the RNG when suitable
|
|
'random' input data is available. Read the section at the end for details
|
|
on the design of the RNG.
|
|
|
|
void RAND_bytes(
|
|
unsigned char *buf,
|
|
int num);
|
|
This routine puts 'num' random bytes into 'buf'. One should make
|
|
sure RAND_seed() has been called before using this routine.
|
|
|
|
void RAND_seed(
|
|
unsigned char *buf,
|
|
int num);
|
|
This routine adds more 'seed' data the RNG state. 'num' bytes
|
|
are added to the RNG state, they are taken from 'buf'. This
|
|
routine can be called with sensitive data such as user entered
|
|
passwords. This sensitive data is in no way recoverable from
|
|
the RAND library routines or state. Try to pass as much data
|
|
from 'random' sources as possible into the RNG via this function.
|
|
Also strongly consider using the RAND_load_file() and
|
|
RAND_write_file() routines.
|
|
|
|
void RAND_cleanup();
|
|
When a program has finished with the RAND library, if it so
|
|
desires, it can 'zero' all RNG state.
|
|
|
|
The following 3 routines are convenience routines that can be used to
|
|
'save' and 'restore' data from/to the RNG and it's state.
|
|
Since the more 'random' data that is feed as seed data the better, why not
|
|
keep it around between executions of the program? Of course the
|
|
application should pass more 'random' data in via RAND_seed() and
|
|
make sure no-one can read the 'random' data file.
|
|
|
|
char *RAND_file_name(
|
|
char *buf,
|
|
int size);
|
|
This routine returns a 'default' name for the location of a 'rand'
|
|
file. The 'rand' file should keep a sequence of random bytes used
|
|
to initialise the RNG. The filename is put in 'buf'. Buf is 'size'
|
|
bytes long. Buf is returned if things go well, if they do not,
|
|
NULL is returned. The 'rand' file name is generated in the
|
|
following way. First, if there is a 'RANDFILE' environment
|
|
variable, it is returned. Second, if there is a 'HOME' environment
|
|
variable, $HOME/.rand is returned. Third, NULL is returned. NULL
|
|
is also returned if a buf would overflow.
|
|
|
|
int RAND_load_file(
|
|
char *file,
|
|
long number);
|
|
This function 'adds' the 'file' into the RNG state. It does this by
|
|
doing a RAND_seed() on the value returned from a stat() system call
|
|
on the file and if 'number' is non-zero, upto 'number' bytes read
|
|
from the file. The number of bytes passed to RAND_seed() is returned.
|
|
|
|
int RAND_write_file(
|
|
char *file),
|
|
RAND_write_file() writes N random bytes to the file 'file', where
|
|
N is the size of the internal RND state (currently 1k).
|
|
This is a suitable method of saving RNG state for reloading via
|
|
RAND_load_file().
|
|
|
|
What follows is a description of this RNG and a description of the rational
|
|
behind it's design.
|
|
|
|
It should be noted that this RNG is intended to be used to generate
|
|
'random' keys for various ciphers including generation of DH and RSA keys.
|
|
|
|
It should also be noted that I have just created a system that I am happy with.
|
|
It may be overkill but that does not worry me. I have not spent that much
|
|
time on this algorithm so if there are glaring errors, please let me know.
|
|
Speed has not been a consideration in the design of these routines.
|
|
|
|
First up I will state the things I believe I need for a good RNG.
|
|
1) A good hashing algorithm to mix things up and to convert the RNG 'state'
|
|
to random numbers.
|
|
2) An initial source of random 'state'.
|
|
3) The state should be very large. If the RNG is being used to generate
|
|
4096 bit RSA keys, 2 2048 bit random strings are required (at a minimum).
|
|
If your RNG state only has 128 bits, you are obviously limiting the
|
|
search space to 128 bits, not 2048. I'm probably getting a little
|
|
carried away on this last point but it does indicate that it may not be
|
|
a bad idea to keep quite a lot of RNG state. It should be easier to
|
|
break a cipher than guess the RNG seed data.
|
|
4) Any RNG seed data should influence all subsequent random numbers
|
|
generated. This implies that any random seed data entered will have
|
|
an influence on all subsequent random numbers generated.
|
|
5) When using data to seed the RNG state, the data used should not be
|
|
extractable from the RNG state. I believe this should be a
|
|
requirement because one possible source of 'secret' semi random
|
|
data would be a private key or a password. This data must
|
|
not be disclosed by either subsequent random numbers or a
|
|
'core' dump left by a program crash.
|
|
6) Given the same initial 'state', 2 systems should deviate in their RNG state
|
|
(and hence the random numbers generated) over time if at all possible.
|
|
7) Given the random number output stream, it should not be possible to determine
|
|
the RNG state or the next random number.
|
|
|
|
|
|
The algorithm is as follows.
|
|
|
|
There is global state made up of a 1023 byte buffer (the 'state'), a
|
|
working message digest ('md') and a counter ('count').
|
|
|
|
Whenever seed data is added, it is inserted into the 'state' as
|
|
follows.
|
|
The input is chopped up into units of 16 bytes (or less for
|
|
the last block). Each of these blocks is run through the MD5
|
|
message digest. The data passed to the MD5 digest is the
|
|
current 'md', the same number of bytes from the 'state'
|
|
(the location determined by in incremented looping index) as
|
|
the current 'block' and the new key data 'block'. The result
|
|
of this is kept in 'md' and also xored into the 'state' at the
|
|
same locations that were used as input into the MD5.
|
|
I believe this system addresses points 1 (MD5), 3 (the 'state'),
|
|
4 (via the 'md'), 5 (by the use of MD5 and xor).
|
|
|
|
When bytes are extracted from the RNG, the following process is used.
|
|
For each group of 8 bytes (or less), we do the following,
|
|
Input into MD5, the top 8 bytes from 'md', the byte that are
|
|
to be overwritten by the random bytes and bytes from the
|
|
'state' (incrementing looping index). From this digest output
|
|
(which is kept in 'md'), the top (upto) 8 bytes are
|
|
returned to the caller and the bottom (upto) 8 bytes are xored
|
|
into the 'state'.
|
|
Finally, after we have finished 'generation' random bytes for the
|
|
called, 'count' (which is incremented) and 'md' are fed into MD5 and
|
|
the results are kept in 'md'.
|
|
I believe the above addressed points 1 (use of MD5), 6 (by
|
|
hashing into the 'state' the 'old' data from the caller that
|
|
is about to be overwritten) and 7 (by not using the 8 bytes
|
|
given to the caller to update the 'state', but they are used
|
|
to update 'md').
|
|
|
|
So of the points raised, only 2 is not addressed, but sources of
|
|
random data will always be a problem.
|
|
|
|
|
|
==== rc2.doc ========================================================
|
|
|
|
The RC2 library.
|
|
|
|
RC2 is a block cipher that operates on 64bit (8 byte) quantities. It
|
|
uses variable size key, but 128bit (16 byte) key would normally be considered
|
|
good. It can be used in all the modes that DES can be used. This
|
|
library implements the ecb, cbc, cfb64, ofb64 modes.
|
|
|
|
I have implemented this library from an article posted to sci.crypt on
|
|
11-Feb-1996. I personally don't know how far to trust the RC2 cipher.
|
|
While it is capable of having a key of any size, not much reseach has
|
|
publically been done on it at this point in time (Apr-1996)
|
|
since the cipher has only been public for a few months :-)
|
|
It is of a similar speed to DES and IDEA, so unless it is required for
|
|
meeting some standard (SSLv2, perhaps S/MIME), it would probably be advisable
|
|
to stick to IDEA, or for the paranoid, Tripple DES.
|
|
|
|
Mind you, having said all that, I should mention that I just read alot and
|
|
implement ciphers, I'm a 'babe in the woods' when it comes to evaluating
|
|
ciphers :-).
|
|
|
|
For all calls that have an 'input' and 'output' variables, they can be the
|
|
same.
|
|
|
|
This library requires the inclusion of 'rc2.h'.
|
|
|
|
All of the encryption functions take what is called an RC2_KEY as an
|
|
argument. An RC2_KEY is an expanded form of the RC2 key.
|
|
For all modes of the RC2 algorithm, the RC2_KEY used for
|
|
decryption is the same one that was used for encryption.
|
|
|
|
The define RC2_ENCRYPT is passed to specify encryption for the functions
|
|
that require an encryption/decryption flag. RC2_DECRYPT is passed to
|
|
specify decryption.
|
|
|
|
Please note that any of the encryption modes specified in my DES library
|
|
could be used with RC2. I have only implemented ecb, cbc, cfb64 and
|
|
ofb64 for the following reasons.
|
|
- ecb is the basic RC2 encryption.
|
|
- cbc is the normal 'chaining' form for block ciphers.
|
|
- cfb64 can be used to encrypt single characters, therefore input and output
|
|
do not need to be a multiple of 8.
|
|
- ofb64 is similar to cfb64 but is more like a stream cipher, not as
|
|
secure (not cipher feedback) but it does not have an encrypt/decrypt mode.
|
|
- If you want triple RC2, thats 384 bits of key and you must be totally
|
|
obsessed with security. Still, if you want it, it is simple enough to
|
|
copy the function from the DES library and change the des_encrypt to
|
|
RC2_encrypt; an exercise left for the paranoid reader :-).
|
|
|
|
The functions are as follows:
|
|
|
|
void RC2_set_key(
|
|
RC2_KEY *ks;
|
|
int len;
|
|
unsigned char *key;
|
|
int bits;
|
|
RC2_set_key converts an 'len' byte key into a RC2_KEY.
|
|
A 'ks' is an expanded form of the 'key' which is used to
|
|
perform actual encryption. It can be regenerated from the RC2 key
|
|
so it only needs to be kept when encryption or decryption is about
|
|
to occur. Don't save or pass around RC2_KEY's since they
|
|
are CPU architecture dependent, 'key's are not. RC2 is an
|
|
interesting cipher in that it can be used with a variable length
|
|
key. 'len' is the length of 'key' to be used as the key.
|
|
A 'len' of 16 is recomended. The 'bits' argument is an
|
|
interesting addition which I only found out about in Aug 96.
|
|
BSAFE uses this parameter to 'limit' the number of bits used
|
|
for the key. To use the 'key' unmodified, set bits to 1024.
|
|
This is what old versions of my RC2 library did (SSLeay 0.6.3).
|
|
RSAs BSAFE library sets this parameter to be 128 if 128 bit
|
|
keys are being used. So to be compatable with BSAFE, set it
|
|
to 128, if you don't want to reduce RC2's key length, leave it
|
|
at 1024.
|
|
|
|
void RC2_encrypt(
|
|
unsigned long *data,
|
|
RC2_KEY *key,
|
|
int encrypt);
|
|
This is the RC2 encryption function that gets called by just about
|
|
every other RC2 routine in the library. You should not use this
|
|
function except to implement 'modes' of RC2. I say this because the
|
|
functions that call this routine do the conversion from 'char *' to
|
|
long, and this needs to be done to make sure 'non-aligned' memory
|
|
access do not occur.
|
|
Data is a pointer to 2 unsigned long's and key is the
|
|
RC2_KEY to use. Encryption or decryption is indicated by 'encrypt'.
|
|
which can have the values RC2_ENCRYPT or RC2_DECRYPT.
|
|
|
|
void RC2_ecb_encrypt(
|
|
unsigned char *in,
|
|
unsigned char *out,
|
|
RC2_KEY *key,
|
|
int encrypt);
|
|
This is the basic Electronic Code Book form of RC2 (in DES this
|
|
mode is called Electronic Code Book so I'm going to use the term
|
|
for rc2 as well.
|
|
Input is encrypted into output using the key represented by
|
|
key. Depending on the encrypt, encryption or
|
|
decryption occurs. Input is 8 bytes long and output is 8 bytes.
|
|
|
|
void RC2_cbc_encrypt(
|
|
unsigned char *in,
|
|
unsigned char *out,
|
|
long length,
|
|
RC2_KEY *ks,
|
|
unsigned char *ivec,
|
|
int encrypt);
|
|
This routine implements RC2 in Cipher Block Chaining mode.
|
|
Input, which should be a multiple of 8 bytes is encrypted
|
|
(or decrypted) to output which will also be a multiple of 8 bytes.
|
|
The number of bytes is in length (and from what I've said above,
|
|
should be a multiple of 8). If length is not a multiple of 8, bad
|
|
things will probably happen. ivec is the initialisation vector.
|
|
This function updates iv after each call so that it can be passed to
|
|
the next call to RC2_cbc_encrypt().
|
|
|
|
void RC2_cfb64_encrypt(
|
|
unsigned char *in,
|
|
unsigned char *out,
|
|
long length,
|
|
RC2_KEY *schedule,
|
|
unsigned char *ivec,
|
|
int *num,
|
|
int encrypt);
|
|
This is one of the more useful functions in this RC2 library, it
|
|
implements CFB mode of RC2 with 64bit feedback.
|
|
This allows you to encrypt an arbitrary number of bytes,
|
|
you do not require 8 byte padding. Each call to this
|
|
routine will encrypt the input bytes to output and then update ivec
|
|
and num. Num contains 'how far' we are though ivec.
|
|
'Encrypt' is used to indicate encryption or decryption.
|
|
CFB64 mode operates by using the cipher to generate a stream
|
|
of bytes which is used to encrypt the plain text.
|
|
The cipher text is then encrypted to generate the next 64 bits to
|
|
be xored (incrementally) with the next 64 bits of plain
|
|
text. As can be seen from this, to encrypt or decrypt,
|
|
the same 'cipher stream' needs to be generated but the way the next
|
|
block of data is gathered for encryption is different for
|
|
encryption and decryption.
|
|
|
|
void RC2_ofb64_encrypt(
|
|
unsigned char *in,
|
|
unsigned char *out,
|
|
long length,
|
|
RC2_KEY *schedule,
|
|
unsigned char *ivec,
|
|
int *num);
|
|
This functions implements OFB mode of RC2 with 64bit feedback.
|
|
This allows you to encrypt an arbitrary number of bytes,
|
|
you do not require 8 byte padding. Each call to this
|
|
routine will encrypt the input bytes to output and then update ivec
|
|
and num. Num contains 'how far' we are though ivec.
|
|
This is in effect a stream cipher, there is no encryption or
|
|
decryption mode.
|
|
|
|
For reading passwords, I suggest using des_read_pw_string() from my DES library.
|
|
To generate a password from a text string, I suggest using MD5 (or MD2) to
|
|
produce a 16 byte message digest that can then be passed directly to
|
|
RC2_set_key().
|
|
|
|
=====
|
|
For more information about the specific RC2 modes in this library
|
|
(ecb, cbc, cfb and ofb), read the section entitled 'Modes of DES' from the
|
|
documentation on my DES library. What is said about DES is directly
|
|
applicable for RC2.
|
|
|
|
|
|
==== rc4.doc ========================================================
|
|
|
|
The RC4 library.
|
|
RC4 is a stream cipher that operates on a byte stream. It can be used with
|
|
any length key but I would recommend normally using 16 bytes.
|
|
|
|
This library requires the inclusion of 'rc4.h'.
|
|
|
|
The RC4 encryption function takes what is called an RC4_KEY as an argument.
|
|
The RC4_KEY is generated by the RC4_set_key function from the key bytes.
|
|
|
|
RC4, being a stream cipher, does not have an encryption or decryption mode.
|
|
It produces a stream of bytes that the input stream is xor'ed against and
|
|
so decryption is just a case of 'encrypting' again with the same key.
|
|
|
|
I have only put in one 'mode' for RC4 which is the normal one. This means
|
|
there is no initialisation vector and there is no feedback of the cipher
|
|
text into the cipher. This implies that you should not ever use the
|
|
same key twice if you can help it. If you do, you leave yourself open to
|
|
known plain text attacks; if you know the plain text and
|
|
corresponding cipher text in one message, all messages that used the same
|
|
key can have the cipher text decoded for the corresponding positions in the
|
|
cipher stream.
|
|
|
|
The main positive feature of RC4 is that it is a very fast cipher; about 4
|
|
times faster that DES. This makes it ideally suited to protocols where the
|
|
key is randomly chosen, like SSL.
|
|
|
|
The functions are as follows:
|
|
|
|
void RC4_set_key(
|
|
RC4_KEY *key;
|
|
int len;
|
|
unsigned char *data);
|
|
This function initialises the RC4_KEY structure with the key passed
|
|
in 'data', which is 'len' bytes long. The key data can be any
|
|
length but 16 bytes seems to be a good number.
|
|
|
|
void RC4(
|
|
RC4_KEY *key;
|
|
unsigned long len;
|
|
unsigned char *in;
|
|
unsigned char *out);
|
|
Do the actual RC4 encryption/decryption. Using the 'key', 'len'
|
|
bytes are transformed from 'in' to 'out'. As mentioned above,
|
|
decryption is the operation as encryption.
|
|
|
|
==== ref.doc ========================================================
|
|
|
|
I have lots more references etc, and will update this list in the future,
|
|
30 Aug 1996 - eay
|
|
|
|
|
|
SSL The SSL Protocol - from Netscapes.
|
|
|
|
RC4 Newsgroups: sci.crypt
|
|
From: sterndark@netcom.com (David Sterndark)
|
|
Subject: RC4 Algorithm revealed.
|
|
Message-ID: <sternCvKL4B.Hyy@netcom.com>
|
|
|
|
RC2 Newsgroups: sci.crypt
|
|
From: pgut01@cs.auckland.ac.nz (Peter Gutmann)
|
|
Subject: Specification for Ron Rivests Cipher No.2
|
|
Message-ID: <4fk39f$f70@net.auckland.ac.nz>
|
|
|
|
MD2 RFC1319 The MD2 Message-Digest Algorithm
|
|
MD5 RFC1321 The MD5 Message-Digest Algorithm
|
|
|
|
X509 Certificates
|
|
RFC1421 Privacy Enhancement for Internet Electronic Mail: Part I
|
|
RFC1422 Privacy Enhancement for Internet Electronic Mail: Part II
|
|
RFC1423 Privacy Enhancement for Internet Electronic Mail: Part III
|
|
RFC1424 Privacy Enhancement for Internet Electronic Mail: Part IV
|
|
|
|
RSA and various standard encoding
|
|
PKCS#1 RSA Encryption Standard
|
|
PKCS#5 Password-Based Encryption Standard
|
|
PKCS#7 Cryptographic Message Syntax Standard
|
|
A Layman's Guide to a Subset of ASN.1, BER, and DER
|
|
An Overview of the PKCS Standards
|
|
Some Examples of the PKCS Standards
|
|
|
|
IDEA Chapter 3 The Block Cipher IDEA
|
|
|
|
RSA, prime number generation and bignum algorithms
|
|
Introduction To Algorithms,
|
|
Thomas Cormen, Charles Leiserson, Ronald Rivest,
|
|
Section 29 Arithmetic Circuits
|
|
Section 33 Number-Theoretic Algorithms
|
|
|
|
Fast Private Key algorithm
|
|
Fast Decipherment Algorithm for RSA Public-Key Cryptosystem
|
|
J.-J. Quisquater and C. Couvreur, Electronics Letters,
|
|
14th October 1982, Vol. 18 No. 21
|
|
|
|
Prime number generation and bignum algorithms.
|
|
PGP-2.3a
|
|
|
|
==== rsa.doc ========================================================
|
|
|
|
The RSA encryption and utility routines.
|
|
|
|
The RSA routines are built on top of a big number library (the BN library).
|
|
There are support routines in the X509 library for loading and manipulating
|
|
the various objects in the RSA library. When errors are returned, read
|
|
about the ERR library for how to access the error codes.
|
|
|
|
All RSA encryption is done according to the PKCS-1 standard which is
|
|
compatible with PEM and RSAref. This means that any values being encrypted
|
|
must be less than the size of the modulus in bytes, minus 10, bytes long.
|
|
|
|
This library uses RAND_bytes()() for it's random data, make sure to feed
|
|
RAND_seed() with lots of interesting and varied data before using these
|
|
routines.
|
|
|
|
The RSA library has one specific data type, the RSA structure.
|
|
It is composed of 8 BIGNUM variables (see the BN library for details) and
|
|
can hold either a private RSA key or a public RSA key.
|
|
Some RSA libraries have different structures for public and private keys, I
|
|
don't. For my libraries, a public key is determined by the fact that the
|
|
RSA->d value is NULL. These routines will operate on any size RSA keys.
|
|
While I'm sure 4096 bit keys are very very secure, they take a lot longer
|
|
to process that 1024 bit keys :-).
|
|
|
|
The function in the RSA library are as follows.
|
|
|
|
RSA *RSA_new();
|
|
This function creates a new RSA object. The sub-fields of the RSA
|
|
type are also malloced so you should always use this routine to
|
|
create RSA variables.
|
|
|
|
void RSA_free(
|
|
RSA *rsa);
|
|
This function 'frees' an RSA structure. This routine should always
|
|
be used to free the RSA structure since it will also 'free' any
|
|
sub-fields of the RSA type that need freeing.
|
|
|
|
int RSA_size(
|
|
RSA *rsa);
|
|
This function returns the size of the RSA modulus in bytes. Why do
|
|
I need this you may ask, well the reason is that when you encrypt
|
|
with RSA, the output string will be the size of the RSA modulus.
|
|
So the output for the RSA_encrypt and the input for the RSA_decrypt
|
|
routines need to be RSA_size() bytes long, because this is how many
|
|
bytes are expected.
|
|
|
|
For the following 4 RSA encryption routines, it should be noted that
|
|
RSA_private_decrypt() should be used on the output from
|
|
RSA_public_encrypt() and RSA_public_decrypt() should be used on
|
|
the output from RSA_private_encrypt().
|
|
|
|
int RSA_public_encrypt(
|
|
int from_len;
|
|
unsigned char *from
|
|
unsigned char *to
|
|
RSA *rsa);
|
|
This function implements RSA public encryption, the rsa variable
|
|
should be a public key (but can be a private key). 'from_len'
|
|
bytes taken from 'from' and encrypted and put into 'to'. 'to' needs
|
|
to be at least RSA_size(rsa) bytes long. The number of bytes
|
|
written into 'to' is returned. -1 is returned on an error. The
|
|
operation performed is
|
|
to = from^rsa->e mod rsa->n.
|
|
|
|
int RSA_private_encrypt(
|
|
int from_len;
|
|
unsigned char *from
|
|
unsigned char *to
|
|
RSA *rsa);
|
|
This function implements RSA private encryption, the rsa variable
|
|
should be a private key. 'from_len' bytes taken from
|
|
'from' and encrypted and put into 'to'. 'to' needs
|
|
to be at least RSA_size(rsa) bytes long. The number of bytes
|
|
written into 'to' is returned. -1 is returned on an error. The
|
|
operation performed is
|
|
to = from^rsa->d mod rsa->n.
|
|
|
|
int RSA_public_decrypt(
|
|
int from_len;
|
|
unsigned char *from
|
|
unsigned char *to
|
|
RSA *rsa);
|
|
This function implements RSA public decryption, the rsa variable
|
|
should be a public key (but can be a private key). 'from_len'
|
|
bytes are taken from 'from' and decrypted. The decrypted data is
|
|
put into 'to'. The number of bytes encrypted is returned. -1 is
|
|
returned to indicate an error. The operation performed is
|
|
to = from^rsa->e mod rsa->n.
|
|
|
|
int RSA_private_decrypt(
|
|
int from_len;
|
|
unsigned char *from
|
|
unsigned char *to
|
|
RSA *rsa);
|
|
This function implements RSA private decryption, the rsa variable
|
|
should be a private key. 'from_len' bytes are taken
|
|
from 'from' and decrypted. The decrypted data is
|
|
put into 'to'. The number of bytes encrypted is returned. -1 is
|
|
returned to indicate an error. The operation performed is
|
|
to = from^rsa->d mod rsa->n.
|
|
|
|
int RSA_mod_exp(
|
|
BIGNUM *n;
|
|
BIGNUM *p;
|
|
RSA *rsa);
|
|
Normally you will never use this routine.
|
|
This is really an internal function which is called by
|
|
RSA_private_encrypt() and RSA_private_decrypt(). It performs
|
|
n=n^p mod rsa->n except that it uses the 5 extra variables in the
|
|
RSA structure to make this more efficient.
|
|
|
|
RSA *RSA_generate_key(
|
|
int bits;
|
|
unsigned long e;
|
|
void (*callback)();
|
|
char *cb_arg;
|
|
This routine is used to generate RSA private keys. It takes
|
|
quite a period of time to run and should only be used to
|
|
generate initial private keys that should then be stored
|
|
for later use. The passed callback function
|
|
will be called periodically so that feedback can be given
|
|
as to how this function is progressing.
|
|
'bits' is the length desired for the modulus, so it would be 1024
|
|
to generate a 1024 bit private key.
|
|
'e' is the value to use for the public exponent 'e'. Traditionally
|
|
it is set to either 3 or 0x10001.
|
|
The callback function (if not NULL) is called in the following
|
|
situations.
|
|
when we have generated a suspected prime number to test,
|
|
callback(0,num1++,cb_arg). When it passes a prime number test,
|
|
callback(1,num2++,cb_arg). When it is rejected as one of
|
|
the 2 primes required due to gcd(prime,e value) != 0,
|
|
callback(2,num3++,cb_arg). When finally accepted as one
|
|
of the 2 primes, callback(3,num4++,cb_arg).
|
|
|
|
|
|
==== rsaref.doc ========================================================
|
|
|
|
This package can be compiled to use the RSAref library.
|
|
This library is not allowed outside of the USA but inside the USA it is
|
|
claimed by RSA to be the only RSA public key library that can be used
|
|
besides BSAFE..
|
|
|
|
There are 2 files, rsaref/rsaref.c and rsaref/rsaref.h that contain the glue
|
|
code to use RSAref. These files were written by looking at the PGP
|
|
source code and seeing which routines it used to access RSAref.
|
|
I have also been sent by some-one a copy of the RSAref header file that
|
|
contains the library error codes.
|
|
|
|
[ Jun 1996 update - I have recently gotten hold of RSAref 2.0 from
|
|
South Africa and have been doing some performace tests. ]
|
|
|
|
They have now been tested against the recently announced RSAEURO
|
|
library.
|
|
|
|
There are 2 ways to use SSLeay and RSAref. First, to build so that
|
|
the programs must be linked with RSAref, add '-DRSAref' to CFLAG in the top
|
|
level makefile and -lrsaref (or where ever you are keeping RSAref) to
|
|
EX_LIBS.
|
|
|
|
To build a makefile via util/mk1mf.pl to do this, use the 'rsaref' option.
|
|
|
|
The second method is to build as per normal and link applications with
|
|
the RSAglue library. The correct library order would be
|
|
cc -o cmd cmd.o -lssl -lRSAglue -lcrypto -lrsaref -ldes
|
|
The RSAglue library is built in the rsa directory and is NOT
|
|
automatically installed.
|
|
|
|
Be warned that the RSAEURO library, that is claimed to be compatible
|
|
with RSAref contains a different value for the maximum number of bits
|
|
supported. This changes structure sizes and so if you are using
|
|
RSAEURO, change the value of RSAref_MAX_BITS in rsa/rsaref.h
|
|
|
|
|
|
==== s_mult.doc ========================================================
|
|
|
|
s_mult is a test program I hacked up on a Sunday for testing non-blocking
|
|
IO. It has a select loop at it's centre that handles multiple readers
|
|
and writers.
|
|
|
|
Try the following command
|
|
ssleay s_mult -echo -nbio -ssl -v
|
|
echo - sends any sent text back to the sender
|
|
nbio - turns on non-blocking IO
|
|
ssl - accept SSL connections, default is normal text
|
|
v - print lots
|
|
type Q<cr> to quit
|
|
|
|
In another window, run the following
|
|
ssleay s_client -pause </etc/termcap
|
|
|
|
The pause option puts in a 1 second pause in each read(2)/write(2) call
|
|
so the other end will have read()s fail.
|
|
|
|
==== session.doc ========================================================
|
|
|
|
I have just checked over and re-worked the session stuff.
|
|
The following brief example will ignore all setup information to do with
|
|
authentication.
|
|
|
|
Things operate as follows.
|
|
|
|
The SSL environment has a 'context', a SSL_CTX structure. This holds the
|
|
cached SSL_SESSIONS (which can be reused) and the certificate lookup
|
|
information. Each SSL structure needs to be associated with a SSL_CTX.
|
|
Normally only one SSL_CTX structure is needed per program.
|
|
|
|
SSL_CTX *SSL_CTX_new(void );
|
|
void SSL_CTX_free(SSL_CTX *);
|
|
These 2 functions create and destroy SSL_CTX structures
|
|
|
|
The SSL_CTX has a session_cache_mode which is by default,
|
|
in SSL_SESS_CACHE_SERVER mode. What this means is that the library
|
|
will automatically add new session-id's to the cache apon sucsessful
|
|
SSL_accept() calls.
|
|
If SSL_SESS_CACHE_CLIENT is set, then client certificates are also added
|
|
to the cache.
|
|
SSL_set_session_cache_mode(ctx,mode) will set the 'mode' and
|
|
SSL_get_session_cache_mode(ctx) will get the cache 'mode'.
|
|
The modes can be
|
|
SSL_SESS_CACHE_OFF - no caching
|
|
SSL_SESS_CACHE_CLIENT - only SSL_connect()
|
|
SSL_SESS_CACHE_SERVER - only SSL_accept()
|
|
SSL_SESS_NO_CACHE_BOTH - Either SSL_accept() or SSL_connect().
|
|
If SSL_SESS_CACHE_NO_AUTO_CLEAR is set, old timed out sessions are
|
|
not automatically removed each 255, SSL_connect()s or SSL_accept()s.
|
|
|
|
By default, apon every 255 successful SSL_connect() or SSL_accept()s,
|
|
the cache is flush. Please note that this could be expensive on
|
|
a heavily loaded SSL server, in which case, turn this off and
|
|
clear the cache of old entries 'manually' (with one of the functions
|
|
listed below) every few hours. Perhaps I should up this number, it is hard
|
|
to say. Remember, the '255' new calls is just a mechanims to get called
|
|
every now and then, in theory at most 255 new session-id's will have been
|
|
added but if 100 are added every minute, you would still have
|
|
500 in the cache before any would start being flushed (assuming a 3 minute
|
|
timeout)..
|
|
|
|
int SSL_CTX_sess_hits(SSL_CTX *ctx);
|
|
int SSL_CTX_sess_misses(SSL_CTX *ctx);
|
|
int SSL_CTX_sess_timeouts(SSL_CTX *ctx);
|
|
These 3 functions return statistics about the SSL_CTX. These 3 are the
|
|
number of session id reuses. hits is the number of reuses, misses are the
|
|
number of lookups that failed, and timeouts is the number of cached
|
|
entries ignored because they had timeouted.
|
|
|
|
ctx->new_session_cb is a function pointer to a function of type
|
|
int new_session_callback(SSL *ssl,SSL_SESSION *new);
|
|
This function, if set in the SSL_CTX structure is called whenever a new
|
|
SSL_SESSION is added to the cache. If the callback returns non-zero, it
|
|
means that the application will have to do a SSL_SESSION_free()
|
|
on the structure (this is
|
|
to do with the cache keeping the reference counts correct, without the
|
|
application needing to know about it.
|
|
The 'active' parameter is the current SSL session for which this connection
|
|
was created.
|
|
|
|
void SSL_CTX_sess_set_new_cb(SSL_CTX *ctx,int (*cb)());
|
|
to set the callback,
|
|
int (*cb)() SSL_CTX_sess_get_new_cb(SSL_CTX *ctx)
|
|
to get the callback.
|
|
|
|
If the 'get session' callback is set, when a session id is looked up and
|
|
it is not in the session-id cache, this callback is called. The callback is
|
|
of the form
|
|
SSL_SESSION *get_session_callback(unsigned char *sess_id,int sess_id_len,
|
|
int *copy);
|
|
|
|
The get_session_callback is intended to return null if no session id is found.
|
|
The reference count on the SSL_SESSION in incremented by the SSL library,
|
|
if copy is 1. Otherwise, the reference count is not modified.
|
|
|
|
void SSL_CTX_sess_set_get_cb(ctx,cb) sets the callback and
|
|
int (*cb)()SSL_CTX_sess_get_get_cb(ctx) returns the callback.
|
|
|
|
These callbacks are basically indended to be used by processes to
|
|
send their session-id's to other processes. I currently have not implemented
|
|
non-blocking semantics for these callbacks, it is upto the appication
|
|
to make the callbacks effiecent if they require blocking (perhaps
|
|
by 'saving' them and then 'posting them' when control returns from
|
|
the SSL_accept().
|
|
|
|
LHASH *SSL_CTX_sessions(SSL_CTX *ctx)
|
|
This returns the session cache. The lhash strucutre can be accessed for
|
|
statistics about the cache.
|
|
|
|
void lh_stats(LHASH *lh, FILE *out);
|
|
void lh_node_stats(LHASH *lh, FILE *out);
|
|
void lh_node_usage_stats(LHASH *lh, FILE *out);
|
|
|
|
can be used to print details about it's activity and current state.
|
|
You can also delve directly into the lhash structure for 14 different
|
|
counters that are kept against the structure. When I wrote the lhash library,
|
|
I was interested in gathering statistics :-).
|
|
Have a read of doc/lhash.doc in the SSLeay distribution area for more details
|
|
on the lhash library.
|
|
|
|
Now as mentioned ealier, when a SSL is created, it needs a SSL_CTX.
|
|
SSL * SSL_new(SSL_CTX *);
|
|
|
|
This stores a session. A session is secret information shared between 2
|
|
SSL contexts. It will only be created if both ends of the connection have
|
|
authenticated their peer to their satisfaction. It basically contains
|
|
the information required to use a particular secret key cipher.
|
|
|
|
To retrieve the SSL_CTX being used by a SSL,
|
|
SSL_CTX *SSL_get_SSL_CTX(SSL *s);
|
|
|
|
Now when a SSL session is established between to programs, the 'session'
|
|
information that is cached in the SSL_CTX can me manipulated by the
|
|
following functions.
|
|
int SSL_set_session(SSL *s, SSL_SESSION *session);
|
|
This will set the SSL_SESSION to use for the next SSL_connect(). If you use
|
|
this function on an already 'open' established SSL connection, 'bad things
|
|
will happen'. This function is meaning-less when used on a ssl strucutre
|
|
that is just about to be used in a SSL_accept() call since the
|
|
SSL_accept() will either create a new session or retrieve one from the
|
|
cache.
|
|
|
|
SSL_SESSION *SSL_get_session(SSL *s);
|
|
This will return the SSL_SESSION for the current SSL, NULL if there is
|
|
no session associated with the SSL structure.
|
|
|
|
The SSL sessions are kept in the SSL_CTX in a hash table, to remove a
|
|
session
|
|
void SSL_CTX_remove_session(SSL_CTX *,SSL_SESSION *c);
|
|
and to add one
|
|
int SSL_CTX_add_session(SSL_CTX *s, SSL_SESSION *c);
|
|
SSL_CTX_add_session() returns 1 if the session was already in the cache (so it
|
|
was not added).
|
|
Whenever a new session is created via SSL_connect()/SSL_accept(),
|
|
they are automatically added to the cache, depending on the session_cache_mode
|
|
settings. SSL_set_session()
|
|
does not add it to the cache. Just call SSL_CTX_add_session() if you do want the
|
|
session added. For a 'client' this would not normally be the case.
|
|
SSL_CTX_add_session() is not normally ever used, except for doing 'evil' things
|
|
which the next 2 funtions help you do.
|
|
|
|
int i2d_SSL_SESSION(SSL_SESSION *in,unsigned char **pp);
|
|
SSL_SESSION *d2i_SSL_SESSION(SSL_SESSION **a,unsigned char **pp,long length);
|
|
These 2 functions are in the standard ASN1 library form and can be used to
|
|
load and save to a byte format, the SSL_SESSION structure.
|
|
With these functions, you can save and read these structures to a files or
|
|
arbitary byte string.
|
|
The PEM_write_SSL_SESSION(fp,x) and PEM_read_SSL_SESSION(fp,x,cb) will
|
|
write to a file pointer in base64 encoding.
|
|
|
|
What you can do with this, is pass session information between separate
|
|
processes. Please note, that you will probably also need to modify the
|
|
timeout information on the SSL_SESSIONs.
|
|
|
|
long SSL_get_time(SSL_SESSION *s)
|
|
will return the 'time' that the session
|
|
was loaded. The timeout is relative to this time. This information is
|
|
saved when the SSL_SESSION is converted to binarary but it is stored
|
|
in as a unix long, which is rather OS dependant, but easy to convert back.
|
|
|
|
long SSL_set_time(SSL_SESSION *s,long t) will set the above mentioned time.
|
|
The time value is just the value returned from time(3), and should really
|
|
be defined by be to be time_t.
|
|
|
|
long SSL_get_timeout(SSL_SESSION *s);
|
|
long SSL_set_timeout(SSL_SESSION *s,long t);
|
|
These 2 retrieve and set the timeout which is just a number of secconds
|
|
from the 'SSL_get_time()' value. When this time period has elapesed,
|
|
the session will no longer be in the cache (well it will actually be removed
|
|
the next time it is attempted to be retrieved, so you could 'bump'
|
|
the timeout so it remains valid).
|
|
The 'time' and 'timeout' are set on a session when it is created, not reset
|
|
each time it is reused. If you did wish to 'bump it', just after establishing
|
|
a connection, do a
|
|
SSL_set_time(ssl,time(NULL));
|
|
|
|
You can also use
|
|
SSL_CTX_set_timeout(SSL_CTX *ctx,unsigned long t) and
|
|
SSL_CTX_get_timeout(SSL_CTX *ctx) to manipulate the default timeouts for
|
|
all SSL connections created against a SSL_CTX. If you set a timeout in
|
|
an SSL_CTX, all new SSL's created will inherit the timeout. It can be over
|
|
written by the SSL_set_timeout(SSL *s,unsigned long t) function call.
|
|
If you 'set' the timeout back to 0, the system default will be used.
|
|
|
|
SSL_SESSION *SSL_SESSION_new();
|
|
void SSL_SESSION_free(SSL_SESSION *ses);
|
|
These 2 functions are used to create and dispose of SSL_SESSION functions.
|
|
You should not ever normally need to use them unless you are using
|
|
i2d_SSL_SESSION() and/or d2i_SSL_SESSION(). If you 'load' a SSL_SESSION
|
|
via d2i_SSL_SESSION(), you will need to SSL_SESSION_free() it.
|
|
Both SSL_set_session() and SSL_CTX_add_session() will 'take copies' of the
|
|
structure (via reference counts) when it is passed to them.
|
|
|
|
SSL_CTX_flush_sessions(ctx,time);
|
|
The first function will clear all sessions from the cache, which have expired
|
|
relative to 'time' (which could just be time(NULL)).
|
|
|
|
SSL_CTX_flush_sessions(ctx,0);
|
|
This is a special case that clears everything.
|
|
|
|
As a final comment, a 'session' is not enough to establish a new
|
|
connection. If a session has timed out, a certificate and private key
|
|
need to have been associated with the SSL structure.
|
|
SSL_copy_session_id(SSL *to,SSL *from); will copy not only the session
|
|
strucutre but also the private key and certificate associated with
|
|
'from'.
|
|
|
|
EXAMPLES.
|
|
|
|
So lets play at being a weird SSL server.
|
|
|
|
/* setup a context */
|
|
ctx=SSL_CTX_new();
|
|
|
|
/* Lets load some session from binary into the cache, why one would do
|
|
* this is not toally clear, but passing between programs does make sense
|
|
* Perhaps you are using 4096 bit keys and are happy to keep them
|
|
* valid for a week, to avoid the RSA overhead of 15 seconds, I'm not toally
|
|
* sure, perhaps this is a process called from an SSL inetd and this is being
|
|
* passed to the application. */
|
|
session=d2i_SSL_SESSION(....)
|
|
SSL_CTX_add_session(ctx,session);
|
|
|
|
/* Lets even add a session from a file */
|
|
session=PEM_read_SSL_SESSION(....)
|
|
SSL_CTX_add_session(ctx,session);
|
|
|
|
/* create a new SSL structure */
|
|
ssl=SSL_new(ctx);
|
|
|
|
/* At this point we want to be able to 'create' new session if
|
|
* required, so we need a certificate and RSAkey. */
|
|
SSL_use_RSAPrivateKey_file(ssl,...)
|
|
SSL_use_certificate_file(ssl,...)
|
|
|
|
/* Now since we are a server, it make little sence to load a session against
|
|
* the ssl strucutre since a SSL_accept() will either create a new session or
|
|
* grab an existing one from the cache. */
|
|
|
|
/* grab a socket descriptor */
|
|
fd=accept(...);
|
|
|
|
/* associated it with the ssl strucutre */
|
|
SSL_set_fd(ssl,fd);
|
|
|
|
SSL_accept(ssl); /* 'do' SSL using out cert and RSA key */
|
|
|
|
/* Lets print out the session details or lets save it to a file,
|
|
* perhaps with a secret key cipher, so that we can pass it to the FBI
|
|
* when they want to decode the session :-). While we have RSA
|
|
* this does not matter much but when I do SSLv3, this will allow a mechanism
|
|
* for the server/client to record the information needed to decode
|
|
* the traffic that went over the wire, even when using Diffie-Hellman */
|
|
PEM_write_SSL_SESSION(SSL_get_session(ssl),stdout,....)
|
|
|
|
Lets 'connect' back to the caller using the same session id.
|
|
|
|
ssl2=SSL_new(ctx);
|
|
fd2=connect(them);
|
|
SSL_set_fd(ssl2,fd2);
|
|
SSL_set_session(ssl2,SSL_get_session(ssl));
|
|
SSL_connect(ssl2);
|
|
|
|
/* what the hell, lets accept no more connections using this session */
|
|
SSL_CTX_remove_session(SSL_get_SSL_CTX(ssl),SSL_get_session(ssl));
|
|
|
|
/* we could have just as easily used ssl2 since they both are using the
|
|
* same session.
|
|
* You will note that both ssl and ssl2 are still using the session, and
|
|
* the SSL_SESSION structure will be free()ed when both ssl and ssl2
|
|
* finish using the session. Also note that you could continue to initiate
|
|
* connections using this session by doing SSL_get_session(ssl) to get the
|
|
* existing session, but SSL_accept() will not be able to find it to
|
|
* use for incoming connections.
|
|
* Of corse, the session will timeout at the far end and it will no
|
|
* longer be accepted after a while. The time and timeout are ignored except
|
|
* by SSL_accept(). */
|
|
|
|
/* Since we have had our server running for 10 weeks, and memory is getting
|
|
* short, perhaps we should clear the session cache to remove those
|
|
* 100000 session entries that have expired. Some may consider this
|
|
* a memory leak :-) */
|
|
|
|
SSL_CTX_flush_sessions(ctx,time(NULL));
|
|
|
|
/* Ok, after a bit more time we wish to flush all sessions from the cache
|
|
* so that all new connections will be authenticated and incure the
|
|
* public key operation overhead */
|
|
|
|
SSL_CTX_flush_sessions(ctx,0);
|
|
|
|
/* As a final note, to copy everything to do with a SSL, use */
|
|
SSL_copy_session_id(SSL *to,SSL *from);
|
|
/* as this also copies the certificate and RSA key so new session can
|
|
* be established using the same details */
|
|
|
|
|
|
==== sha.doc ========================================================
|
|
|
|
The SHA (Secure Hash Algorithm) library.
|
|
SHA is a message digest algorithm that can be used to condense an arbitrary
|
|
length message down to a 20 byte hash. The functions all need to be passed
|
|
a SHA_CTX which is used to hold the SHA context during multiple SHA_Update()
|
|
function calls. The normal method of use for this library is as follows
|
|
This library contains both SHA and SHA-1 digest algorithms. SHA-1 is
|
|
an update to SHA (which should really be called SHA-0 now) which
|
|
tweaks the algorithm slightly. The SHA-1 algorithm is used by simply
|
|
using SHA1_Init(), SHA1_Update(), SHA1_Final() and SHA1() instead of the
|
|
SHA*() calls
|
|
|
|
SHA_Init(...);
|
|
SHA_Update(...);
|
|
...
|
|
SHA_Update(...);
|
|
SHA_Final(...);
|
|
|
|
This library requires the inclusion of 'sha.h'.
|
|
|
|
The functions are as follows:
|
|
|
|
void SHA_Init(
|
|
SHA_CTX *c);
|
|
This function needs to be called to initiate a SHA_CTX structure for
|
|
use.
|
|
|
|
void SHA_Update(
|
|
SHA_CTX *c;
|
|
unsigned char *data;
|
|
unsigned long len);
|
|
This updates the message digest context being generated with 'len'
|
|
bytes from the 'data' pointer. The number of bytes can be any
|
|
length.
|
|
|
|
void SHA_Final(
|
|
unsigned char *md;
|
|
SHA_CTX *c;
|
|
This function is called when a message digest of the data digested
|
|
with SHA_Update() is wanted. The message digest is put in the 'md'
|
|
array and is SHA_DIGEST_LENGTH (20) bytes long.
|
|
|
|
unsigned char *SHA(
|
|
unsigned char *d;
|
|
unsigned long n;
|
|
unsigned char *md;
|
|
This function performs a SHA_Init(), followed by a SHA_Update()
|
|
followed by a SHA_Final() (using a local SHA_CTX).
|
|
The resulting digest is put into 'md' if it is not NULL.
|
|
Regardless of the value of 'md', the message
|
|
digest is returned from the function. If 'md' was NULL, the message
|
|
digest returned is being stored in a static structure.
|
|
|
|
|
|
==== speed.doc ========================================================
|
|
|
|
To get an idea of the performance of this library, use
|
|
ssleay speed
|
|
|
|
perl util/sp-diff.pl file1 file2
|
|
|
|
will print out the relative differences between the 2 files which are
|
|
expected to be the output from the speed program.
|
|
|
|
The performace of the library is very dependant on the Compiler
|
|
quality and various flags used to build.
|
|
|
|
---
|
|
|
|
These are some numbers I did comparing RSAref and SSLeay on a Pentium 100.
|
|
[ These numbers are all out of date, as of SSL - 0.6.1 the RSA
|
|
operations are about 2 times faster, so check the version number ]
|
|
|
|
RSA performance.
|
|
|
|
SSLeay 0.6.0
|
|
Pentium 100, 32meg, Windows NT Workstation 3.51
|
|
linux - gcc v 2.7.0 -O3 -fomit-frame-pointer -m486
|
|
and
|
|
Windows NT - Windows NT 3.51 - Visual C++ 4.1 - 586 code + 32bit assember
|
|
Windows 3.1 - Windows NT 3.51 - Visual C++ 1.52c - 286 code + 32bit assember
|
|
NT Dos Shell- Windows NT 3.51 - Visual C++ 1.52c - 286 code + 16bit assember
|
|
|
|
Times are how long it takes to do an RSA private key operation.
|
|
|
|
512bits 1024bits
|
|
-------------------------------
|
|
SSLeay NT dll 0.042s 0.202s see above
|
|
SSLeay linux 0.046s 0.218s Assember inner loops (normal build)
|
|
SSLeay linux 0.067s 0.380s Pure C code with BN_LLONG defined
|
|
SSLeay W3.1 dll 0.108s 0.478s see above
|
|
SSLeay linux 0.109s 0.713s C without BN_LLONG.
|
|
RSAref2.0 linux 0.149s 0.936s
|
|
SSLeay MS-DOS 0.197s 1.049s see above
|
|
|
|
486DX66, 32meg, Windows NT Server 3.51
|
|
512bits 1024bits
|
|
-------------------------------
|
|
SSLeay NT dll 0.084s 0.495s <- SSLeay 0.6.3
|
|
SSLeay NT dll 0.154s 0.882s
|
|
SSLeay W3.1 dll 0.335s 1.538s
|
|
SSLeay MS-DOS 0.490s 2.790s
|
|
|
|
What I find cute is that I'm still faster than RSAref when using standard C,
|
|
without using the 'long long' data type :-), %35 faster for 512bit and we
|
|
scale up to 3.2 times faster for the 'default linux' build. I should mention
|
|
that people should 'try' to use either x86-lnx.s (elf), x86-lnxa.s or
|
|
x86-sol.s for any x86 based unix they are building on. The only problems
|
|
with be with syntax but the performance gain is quite large, especially for
|
|
servers. The code is very simple, you just need to modify the 'header'.
|
|
|
|
The message is, if you are stuck using RSAref, the RSA performance will be
|
|
bad. Considering the code was compiled for a pentium, the 486DX66 number
|
|
would indicate 'Use RSAref and turn you Pentium 100 into a 486DX66' :-).
|
|
[ As of verson 0.6.1, it would be correct to say 'turn you pentium 100
|
|
into a 486DX33' :-) ]
|
|
|
|
I won't tell people if the DLL's are using RSAref or my stuff if no-one
|
|
asks :-).
|
|
|
|
eric
|
|
|
|
PS while I know I could speed things up further, I will probably not do
|
|
so due to the effort involved. I did do some timings on the
|
|
SSLeay bignum format -> RSAref number format conversion that occurs
|
|
each time RSAref is used by SSLeay, and the numbers are trivial.
|
|
0.00012s a call for 512bit vs 0.149s for the time spent in the function.
|
|
0.00018s for 1024bit vs 0.938s. Insignificant.
|
|
So the 'way to go', to support faster RSA libraries, if people are keen,
|
|
is to write 'glue' code in a similar way that I do for RSAref and send it
|
|
to me :-).
|
|
My base library still has the advantage of being able to operate on
|
|
any size numbers, and is not that far from the performance from the
|
|
leaders in the field. (-%30?)
|
|
[ Well as of 0.6.1 I am now the leader in the filed on x86 (we at
|
|
least very close :-) ]
|
|
|
|
I suppose I should also mention some other numbers RSAref numbers, again
|
|
on my Pentium.
|
|
DES CBC EDE-DES MD5
|
|
RSAref linux 830k/s 302k/s 4390k/s
|
|
SSLeay linux 855k/s 319k/s 10025k/s
|
|
SSLeay NT 1158k/s 410k/s 10470k/s
|
|
SSLeay w31 378k/s 143k/s 2383k/s (fully 16bit)
|
|
|
|
Got to admit that Visual C++ 4.[01] is a damn fine compiler :-)
|
|
--
|
|
Eric Young | BOOL is tri-state according to Bill Gates.
|
|
AARNet: eay@cryptsoft.com | RTFM Win32 GetMessage().
|
|
|
|
|
|
|
|
|
|
==== ssl-ciph.doc ========================================================
|
|
|
|
This is a quick high level summery of how things work now.
|
|
|
|
Each SSLv2 and SSLv3 cipher is composed of 4 major attributes plus a few extra
|
|
minor ones.
|
|
|
|
They are 'The key exchange algorithm', which is RSA for SSLv2 but can also
|
|
be Diffle-Hellman for SSLv3.
|
|
|
|
An 'Authenticion algorithm', which can be RSA, Diffle-Helman, DSS or
|
|
none.
|
|
|
|
The cipher
|
|
|
|
The MAC digest.
|
|
|
|
A cipher can also be an export cipher and is either an SSLv2 or a
|
|
SSLv3 ciphers.
|
|
|
|
To specify which ciphers to use, one can either specify all the ciphers,
|
|
one at a time, or use 'aliases' to specify the preference and order for
|
|
the ciphers.
|
|
|
|
There are a large number of aliases, but the most importaint are
|
|
kRSA, kDHr, kDHd and kEDH for key exchange types.
|
|
|
|
aRSA, aDSS, aNULL and aDH for authentication
|
|
DES, 3DES, RC4, RC2, IDEA and eNULL for ciphers
|
|
MD5, SHA0 and SHA1 digests
|
|
|
|
Now where this becomes interesting is that these can be put together to
|
|
specify the order and ciphers you wish to use.
|
|
|
|
To speed this up there are also aliases for certian groups of ciphers.
|
|
The main ones are
|
|
SSLv2 - all SSLv2 ciphers
|
|
SSLv3 - all SSLv3 ciphers
|
|
EXP - all export ciphers
|
|
LOW - all low strngth ciphers (no export ciphers, normally single DES)
|
|
MEDIUM - 128 bit encryption
|
|
HIGH - Triple DES
|
|
|
|
These aliases can be joined in a : separated list which specifies to
|
|
add ciphers, move them to the current location and delete them.
|
|
|
|
A simpler way to look at all of this is to use the 'ssleay ciphers -v' command.
|
|
The default library cipher spec is
|
|
!ADH:RC4+RSA:HIGH:MEDIUM:LOW:EXP:+SSLv2:+EXP
|
|
which means, first, remove from consideration any ciphers that do not
|
|
authenticate. Next up, use ciphers using RC4 and RSA. Next include the HIGH,
|
|
MEDIUM and the LOW security ciphers. Finish up by adding all the export
|
|
ciphers on the end, then 'pull' all the SSLv2 and export ciphers to
|
|
the end of the list.
|
|
|
|
The results are
|
|
$ ssleay ciphers -v '!ADH:RC4+RSA:HIGH:MEDIUM:LOW:EXP:+SSLv2:+EXP'
|
|
|
|
RC4-SHA SSLv3 Kx=RSA Au=RSA Enc=RC4(128) Mac=SHA1
|
|
RC4-MD5 SSLv3 Kx=RSA Au=RSA Enc=RC4(128) Mac=MD5
|
|
EDH-RSA-DES-CBC3-SHA SSLv3 Kx=DH Au=RSA Enc=3DES(168) Mac=SHA1
|
|
EDH-DSS-DES-CBC3-SHA SSLv3 Kx=DH Au=DSS Enc=3DES(168) Mac=SHA1
|
|
DES-CBC3-SHA SSLv3 Kx=RSA Au=RSA Enc=3DES(168) Mac=SHA1
|
|
IDEA-CBC-MD5 SSLv3 Kx=RSA Au=RSA Enc=IDEA(128) Mac=SHA1
|
|
EDH-RSA-DES-CBC-SHA SSLv3 Kx=DH Au=RSA Enc=DES(56) Mac=SHA1
|
|
EDH-DSS-DES-CBC-SHA SSLv3 Kx=DH Au=DSS Enc=DES(56) Mac=SHA1
|
|
DES-CBC-SHA SSLv3 Kx=RSA Au=RSA Enc=DES(56) Mac=SHA1
|
|
DES-CBC3-MD5 SSLv2 Kx=RSA Au=RSA Enc=3DES(168) Mac=MD5
|
|
DES-CBC-MD5 SSLv2 Kx=RSA Au=RSA Enc=DES(56) Mac=MD5
|
|
IDEA-CBC-MD5 SSLv2 Kx=RSA Au=RSA Enc=IDEA(128) Mac=MD5
|
|
RC2-CBC-MD5 SSLv2 Kx=RSA Au=RSA Enc=RC2(128) Mac=MD5
|
|
RC4-MD5 SSLv2 Kx=RSA Au=RSA Enc=RC4(128) Mac=MD5
|
|
EXP-EDH-RSA-DES-CBC SSLv3 Kx=DH(512) Au=RSA Enc=DES(40) Mac=SHA1 export
|
|
EXP-EDH-DSS-DES-CBC-SHA SSLv3 Kx=DH(512) Au=DSS Enc=DES(40) Mac=SHA1 export
|
|
EXP-DES-CBC-SHA SSLv3 Kx=RSA(512) Au=RSA Enc=DES(40) Mac=SHA1 export
|
|
EXP-RC2-CBC-MD5 SSLv3 Kx=RSA(512) Au=RSA Enc=RC2(40) Mac=MD5 export
|
|
EXP-RC4-MD5 SSLv3 Kx=RSA(512) Au=RSA Enc=RC4(40) Mac=MD5 export
|
|
EXP-RC2-CBC-MD5 SSLv2 Kx=RSA(512) Au=RSA Enc=RC2(40) Mac=MD5 export
|
|
EXP-RC4-MD5 SSLv2 Kx=RSA(512) Au=RSA Enc=RC4(40) Mac=MD5 export
|
|
|
|
I would recoment people use the 'ssleay ciphers -v "text"'
|
|
command to check what they are going to use.
|
|
|
|
Anyway, I'm falling asleep here so I'll do some more tomorrow.
|
|
|
|
eric
|
|
|
|
==== ssl.doc ========================================================
|
|
|
|
SSL_CTX_sessions(SSL_CTX *ctx) - the session-id hash table.
|
|
|
|
/* Session-id cache stats */
|
|
SSL_CTX_sess_number
|
|
SSL_CTX_sess_connect
|
|
SSL_CTX_sess_connect_good
|
|
SSL_CTX_sess_accept
|
|
SSL_CTX_sess_accept_good
|
|
SSL_CTX_sess_hits
|
|
SSL_CTX_sess_cb_hits
|
|
SSL_CTX_sess_misses
|
|
SSL_CTX_sess_timeouts
|
|
|
|
/* Session-id application notification callbacks */
|
|
SSL_CTX_sess_set_new_cb
|
|
SSL_CTX_sess_get_new_cb
|
|
SSL_CTX_sess_set_get_cb
|
|
SSL_CTX_sess_get_get_cb
|
|
|
|
/* Session-id cache operation mode */
|
|
SSL_CTX_set_session_cache_mode
|
|
SSL_CTX_get_session_cache_mode
|
|
|
|
/* Set default timeout values to use. */
|
|
SSL_CTX_set_timeout
|
|
SSL_CTX_get_timeout
|
|
|
|
/* Global SSL initalisation informational callback */
|
|
SSL_CTX_set_info_callback
|
|
SSL_CTX_get_info_callback
|
|
SSL_set_info_callback
|
|
SSL_get_info_callback
|
|
|
|
/* If the SSL_accept/SSL_connect returned with -1, these indicate when
|
|
* we should re-call *.
|
|
SSL_want
|
|
SSL_want_nothing
|
|
SSL_want_read
|
|
SSL_want_write
|
|
SSL_want_x509_lookup
|
|
|
|
/* Where we are in SSL initalisation, used in non-blocking, perhaps
|
|
* have a look at ssl/bio_ssl.c */
|
|
SSL_state
|
|
SSL_is_init_finished
|
|
SSL_in_init
|
|
SSL_in_connect_init
|
|
SSL_in_accept_init
|
|
|
|
/* Used to set the 'inital' state so SSL_in_connect_init and SSL_in_accept_init
|
|
* can be used to work out which function to call. */
|
|
SSL_set_connect_state
|
|
SSL_set_accept_state
|
|
|
|
/* Where to look for certificates for authentication */
|
|
SSL_set_default_verify_paths /* calles SSL_load_verify_locations */
|
|
SSL_load_verify_locations
|
|
|
|
/* get info from an established connection */
|
|
SSL_get_session
|
|
SSL_get_certificate
|
|
SSL_get_SSL_CTX
|
|
|
|
SSL_CTX_new
|
|
SSL_CTX_free
|
|
SSL_new
|
|
SSL_clear
|
|
SSL_free
|
|
|
|
SSL_CTX_set_cipher_list
|
|
SSL_get_cipher
|
|
SSL_set_cipher_list
|
|
SSL_get_cipher_list
|
|
SSL_get_shared_ciphers
|
|
|
|
SSL_accept
|
|
SSL_connect
|
|
SSL_read
|
|
SSL_write
|
|
|
|
SSL_debug
|
|
|
|
SSL_get_read_ahead
|
|
SSL_set_read_ahead
|
|
SSL_set_verify
|
|
|
|
SSL_pending
|
|
|
|
SSL_set_fd
|
|
SSL_set_rfd
|
|
SSL_set_wfd
|
|
SSL_set_bio
|
|
SSL_get_fd
|
|
SSL_get_rbio
|
|
SSL_get_wbio
|
|
|
|
SSL_use_RSAPrivateKey
|
|
SSL_use_RSAPrivateKey_ASN1
|
|
SSL_use_RSAPrivateKey_file
|
|
SSL_use_PrivateKey
|
|
SSL_use_PrivateKey_ASN1
|
|
SSL_use_PrivateKey_file
|
|
SSL_use_certificate
|
|
SSL_use_certificate_ASN1
|
|
SSL_use_certificate_file
|
|
|
|
ERR_load_SSL_strings
|
|
SSL_load_error_strings
|
|
|
|
/* human readable version of the 'state' of the SSL connection. */
|
|
SSL_state_string
|
|
SSL_state_string_long
|
|
/* These 2 report what kind of IO operation the library was trying to
|
|
* perform last. Probably not very usefull. */
|
|
SSL_rstate_string
|
|
SSL_rstate_string_long
|
|
|
|
SSL_get_peer_certificate
|
|
|
|
SSL_SESSION_new
|
|
SSL_SESSION_print_fp
|
|
SSL_SESSION_print
|
|
SSL_SESSION_free
|
|
i2d_SSL_SESSION
|
|
d2i_SSL_SESSION
|
|
|
|
SSL_get_time
|
|
SSL_set_time
|
|
SSL_get_timeout
|
|
SSL_set_timeout
|
|
SSL_copy_session_id
|
|
SSL_set_session
|
|
SSL_CTX_add_session
|
|
SSL_CTX_remove_session
|
|
SSL_CTX_flush_sessions
|
|
|
|
BIO_f_ssl
|
|
|
|
/* used to hold information as to why a certificate verification failed */
|
|
SSL_set_verify_result
|
|
SSL_get_verify_result
|
|
|
|
/* can be used by the application to associate data with an SSL structure.
|
|
* It needs to be 'free()ed' by the application */
|
|
SSL_set_app_data
|
|
SSL_get_app_data
|
|
|
|
/* The following all set values that are kept in the SSL_CTX but
|
|
* are used as the default values when an SSL session is created.
|
|
* They are over writen by the relevent SSL_xxxx functions */
|
|
|
|
/* SSL_set_verify */
|
|
void SSL_CTX_set_default_verify
|
|
|
|
/* This callback, if set, totaly overrides the normal SSLeay verification
|
|
* functions and should return 1 on sucesss and 0 on failure */
|
|
void SSL_CTX_set_cert_verify_callback
|
|
|
|
/* The following are the same as the equivilent SSL_xxx functions.
|
|
* Only one copy of this information is kept and if a particular
|
|
* SSL structure has a local override, it is totally separate structure.
|
|
*/
|
|
int SSL_CTX_use_RSAPrivateKey
|
|
int SSL_CTX_use_RSAPrivateKey_ASN1
|
|
int SSL_CTX_use_RSAPrivateKey_file
|
|
int SSL_CTX_use_PrivateKey
|
|
int SSL_CTX_use_PrivateKey_ASN1
|
|
int SSL_CTX_use_PrivateKey_file
|
|
int SSL_CTX_use_certificate
|
|
int SSL_CTX_use_certificate_ASN1
|
|
int SSL_CTX_use_certificate_file
|
|
|
|
|
|
==== ssl_ctx.doc ========================================================
|
|
|
|
This is now a bit dated, quite a few of the SSL_ functions could be
|
|
SSL_CTX_ functions. I will update this in the future. 30 Aug 1996
|
|
|
|
From eay@orb.mincom.oz.au Mon Dec 11 21:37:08 1995
|
|
Received: by orb.mincom.oz.au id AA00696
|
|
(5.65c/IDA-1.4.4 for eay); Mon, 11 Dec 1995 11:37:08 +1000
|
|
Date: Mon, 11 Dec 1995 11:37:08 +1000 (EST)
|
|
From: Eric Young <eay@mincom.oz.au>
|
|
X-Sender: eay@orb
|
|
To: sameer <sameer@c2.org>
|
|
Cc: Eric Young <eay@mincom.oz.au>
|
|
Subject: Re: PEM_readX509 oesn't seem to be working
|
|
In-Reply-To: <199512110102.RAA12521@infinity.c2.org>
|
|
Message-Id: <Pine.SOL.3.91.951211112115.28608D-100000@orb>
|
|
Mime-Version: 1.0
|
|
Content-Type: TEXT/PLAIN; charset=US-ASCII
|
|
Status: RO
|
|
X-Status:
|
|
|
|
On Sun, 10 Dec 1995, sameer wrote:
|
|
> OK, that's solved. I've found out that it is saying "no
|
|
> certificate set" in SSL_accept because s->conn == NULL
|
|
> so there is some place I need to initialize s->conn that I am
|
|
> not initializing it.
|
|
|
|
The full order of things for a server should be.
|
|
|
|
ctx=SSL_CTX_new();
|
|
|
|
/* The next line should not really be using ctx->cert but I'll leave it
|
|
* this way right now... I don't want a X509_ routine to know about an SSL
|
|
* structure, there should be an SSL_load_verify_locations... hmm, I may
|
|
* add it tonight.
|
|
*/
|
|
X509_load_verify_locations(ctx->cert,CAfile,CApath);
|
|
|
|
/* Ok now for each new connection we do the following */
|
|
con=SSL_new(ctx);
|
|
SSL_set_fd(con,s);
|
|
SSL_set_verify(con,verify,verify_callback);
|
|
|
|
/* set the certificate and private key to use. */
|
|
SSL_use_certificate_ASN1(con,X509_certificate);
|
|
SSL_use_RSAPrivateKey_ASN1(con,RSA_private_key);
|
|
|
|
SSL_accept(con);
|
|
|
|
SSL_read(con)/SSL_write(con);
|
|
|
|
There is a bit more than that but that is basically the structure.
|
|
|
|
Create a context and specify where to lookup certificates.
|
|
|
|
foreach connection
|
|
{
|
|
create a SSL structure
|
|
set the certificate and private key
|
|
do a SSL_accept
|
|
|
|
we should now be ok
|
|
}
|
|
|
|
eric
|
|
--
|
|
Eric Young | Signature removed since it was generating
|
|
AARNet: eay@mincom.oz.au | more followups than the message contents :-)
|
|
|
|
|
|
|
|
==== ssleay.doc ========================================================
|
|
|
|
SSLeay: a cryptographic kitchen sink.
|
|
|
|
1st December 1995
|
|
Way back at the start of April 1995, I was looking for a mindless
|
|
programming project. A friend of mine (Tim Hudson) said "why don't you do SSL,
|
|
it has DES encryption in it and I would not mind using it in a SSL telnet".
|
|
While it was true I had written a DES library in previous years, litle
|
|
did I know what an expansive task SSL would turn into.
|
|
|
|
First of all, the SSL protocol contains DES encryption. Well and good. My
|
|
DES library was fast and portable. It also contained the RSA's RC4 stream
|
|
cipher. Again, not a problem, some-one had just posted to sci.crypt
|
|
something that was claimed to be RC4. It also contained IDEA, I had the
|
|
specifications, not a problem to implement. MD5, an RFC, trivial, at most
|
|
I could spend a week or so trying to see if I could speed up the
|
|
implementation. All in all a nice set of ciphers.
|
|
Then the first 'expantion of the scope', RSA public key
|
|
encryption. Since I did not knowing a thing about public key encryption
|
|
or number theory, this appeared quite a daunting task. Just writing a
|
|
big number library would be problomatic in itself, let alone making it fast.
|
|
At this point the scope of 'implementing SSL' expands eponentialy.
|
|
First of all, the RSA private keys were being kept in ASN.1 format.
|
|
Thankfully the RSA PKCS series of documents explains this format. So I now
|
|
needed to be able to encode and decode arbitary ASN.1 objects. The Public
|
|
keys were embeded in X509 certificates. Hmm... these are not only
|
|
ASN.1 objects but they make up a heirachy of authentication. To
|
|
authenticate a X509 certificate one needs to retrieve it's issuers
|
|
certificate etc etc. Hmm..., so I also need to implement some kind
|
|
of certificate management software. I would also have to implement
|
|
software to authenticate certificates. At this point the support code made
|
|
the SSL part of my library look quite small.
|
|
Around this time, the first version of SSLeay was released.
|
|
|
|
Ah, but here was the problem, I was not happy with the code so far. As may
|
|
have become obvious, I had been treating all of this as a learning
|
|
exersize, so I have completely written the library myself. As such, due
|
|
to the way it had grown like a fungus, much of the library was not
|
|
'elagent' or neat. There were global and static variables all over the
|
|
place, the SSL part did not even handle non-blocking IO.
|
|
The Great rewrite began.
|
|
|
|
As of this point in time, the 'Great rewrite' has almost finished. So what
|
|
follows is an approximate list of what is actually SSLeay 0.5.0
|
|
|
|
/********* This needs to be updated for 0.6.0+ *************/
|
|
|
|
---
|
|
The library contains the following routines. Please note that most of these
|
|
functions are not specfic for SSL or any other particular cipher
|
|
implementation. I have tried to make all the routines as general purpose
|
|
as possible. So you should not think of this library as an SSL
|
|
implemtation, but rather as a library of cryptographic functions
|
|
that also contains SSL. I refer to each of these function groupings as
|
|
libraries since they are often capable of functioning as independant
|
|
libraries
|
|
|
|
First up, the general ciphers and message digests supported by the library.
|
|
|
|
MD2 rfc???, a standard 'by parts' interface to this algorithm.
|
|
MD5 rfc???, the same type of interface as for the MD2 library except a
|
|
different algorithm.
|
|
SHA THe Secure Hash Algorithm. Again the same type of interface as
|
|
MD2/MD5 except the digest is 20 bytes.
|
|
SHA1 The 'revised' version of SHA. Just about identical to SHA except
|
|
for one tweak of an inner loop.
|
|
DES This is my libdes library that has been floating around for the last
|
|
few years. It has been enhanced for no other reason than completeness.
|
|
It now supports ecb, cbc, cfb, ofb, cfb64, ofb64 in normal mode and
|
|
triple DES modes of ecb, cbc, cfb64 and ofb64. cfb64 and ofb64 are
|
|
functional interfaces to the 64 bit modes of cfb and ofb used in
|
|
such a way thay they function as single character interfaces.
|
|
RC4 The RSA Inc. stream cipher.
|
|
RC2 The RSA Inc. block cipher.
|
|
IDEA An implmentation of the IDEA cipher, the library supports ecb, cbc,
|
|
cfb64 and ofb64 modes of operation.
|
|
|
|
Now all the above mentioned ciphers and digests libraries support high
|
|
speed, minimal 'crap in the way' type interfaces. For fastest and
|
|
lowest level access, these routines should be used directly.
|
|
|
|
Now there was also the matter of public key crypto systems. These are
|
|
based on large integer arithmatic.
|
|
|
|
BN This is my large integer library. It supports all the normal
|
|
arithmentic operations. It uses malloc extensivly and as such has
|
|
no limits of the size of the numbers being manipulated. If you
|
|
wish to use 4000 bit RSA moduli, these routines will handle it.
|
|
This library also contains routines to 'generate' prime numbers and
|
|
to test for primality. The RSA and DH libraries sit on top of this
|
|
library. As of this point in time, I don't support SHA, but
|
|
when I do add it, it will just sit on top of the routines contained
|
|
in this library.
|
|
RSA This implements the RSA public key algorithm. It also contains
|
|
routines that will generate a new private/public key pair.
|
|
All the RSA functions conform to the PKCS#1 standard.
|
|
DH This is an implementation of the
|
|
Diffie-Hellman protocol. There are all the require routines for
|
|
the protocol, plus extra routines that can be used to generate a
|
|
strong prime for use with a specified generator. While this last
|
|
routine is not generally required by applications implementing DH,
|
|
It is present for completeness and because I thing it is much
|
|
better to be able to 'generate' your own 'magic' numbers as oposed
|
|
to using numbers suplied by others. I conform to the PKCS#3
|
|
standard where required.
|
|
|
|
You may have noticed the preceeding section mentions the 'generation' of
|
|
prime numbers. Now this requries the use of 'random numbers'.
|
|
|
|
RAND This psuedo-random number library is based on MD5 at it's core
|
|
and a large internal state (2k bytes). Once you have entered enough
|
|
seed data into this random number algorithm I don't feel
|
|
you will ever need to worry about it generating predictable output.
|
|
Due to the way I am writing a portable library, I have left the
|
|
issue of how to get good initial random seed data upto the
|
|
application but I do have support routines for saving and loading a
|
|
persistant random number state for use between program runs.
|
|
|
|
Now to make all these ciphers easier to use, a higher level
|
|
interface was required. In this form, the same function would be used to
|
|
encrypt 'by parts', via any one of the above mentioned ciphers.
|
|
|
|
EVP The Digital EnVeloPe library is quite large. At it's core are
|
|
function to perform encryption and decryption by parts while using
|
|
an initial parameter to specify which of the 17 different ciphers
|
|
or 4 different message digests to use. On top of these are implmented
|
|
the digital signature functions, sign, verify, seal and open.
|
|
Base64 encoding of binary data is also done in this library.
|
|
|
|
PEM rfc???? describe the format for Privacy Enhanced eMail.
|
|
As part of this standard, methods of encoding digital enveloped
|
|
data is an ascii format are defined. As such, I use a form of these
|
|
to encode enveloped data. While at this point in time full support
|
|
for PEM has not been built into the library, a minimal subset of
|
|
the secret key and Base64 encoding is present. These reoutines are
|
|
mostly used to Ascii encode binary data with a 'type' associated
|
|
with it and perhaps details of private key encryption used to
|
|
encrypt the data.
|
|
|
|
PKCS7 This is another Digital Envelope encoding standard which uses ASN.1
|
|
to encode the data. At this point in time, while there are some
|
|
routines to encode and decode this binary format, full support is
|
|
not present.
|
|
|
|
As Mentioned, above, there are several different ways to encode
|
|
data structures.
|
|
|
|
ASN1 This library is more a set of primatives used to encode the packing
|
|
and unpacking of data structures. It is used by the X509
|
|
certificate standard and by the PKCS standards which are used by
|
|
this library. It also contains routines for duplicating and signing
|
|
the structures asocisated with X509.
|
|
|
|
X509 The X509 library contains routines for packing and unpacking,
|
|
verifying and just about every thing else you would want to do with
|
|
X509 certificates.
|
|
|
|
PKCS7 PKCS-7 is a standard for encoding digital envelope data
|
|
structures. At this point in time the routines will load and save
|
|
DER forms of these structees. They need to be re-worked to support
|
|
the BER form which is the normal way PKCS-7 is encoded. If the
|
|
previous 2 sentances don't make much sense, don't worry, this
|
|
library is not used by this version of SSLeay anyway.
|
|
|
|
OBJ ASN.1 uses 'object identifiers' to identify objects. A set of
|
|
functions were requred to translate from ASN.1 to an intenger, to a
|
|
character string. This library provieds these translations
|
|
|
|
Now I mentioned an X509 library. X509 specified a hieachy of certificates
|
|
which needs to be traversed to authenticate particular certificates.
|
|
|
|
METH This library is used to push 'methods' of retrieving certificates
|
|
into the library. There are some supplied 'methods' with SSLeay
|
|
but applications can add new methods if they so desire.
|
|
This library has not been finished and is not being used in this
|
|
version.
|
|
|
|
Now all the above are required for use in the initial point of this project.
|
|
|
|
SSL The SSL protocol. This is a full implmentation of SSL v 2. It
|
|
support both server and client authentication. SSL v 3 support
|
|
will be added when the SSL v 3 specification is released in it's
|
|
final form.
|
|
|
|
Now quite a few of the above mentioned libraries rely on a few 'complex'
|
|
data structures. For each of these I have a library.
|
|
|
|
Lhash This is a hash table library which is used extensivly.
|
|
|
|
STACK An implemetation of a Stack data structure.
|
|
|
|
BUF A simple character array structure that also support a function to
|
|
check that the array is greater that a certain size, if it is not,
|
|
it is realloced so that is it.
|
|
|
|
TXT_DB A simple memory based text file data base. The application can specify
|
|
unique indexes that will be enforced at update time.
|
|
|
|
CONF Most of the programs written for this library require a configuration
|
|
file. Instead of letting programs constantly re-implment this
|
|
subsystem, the CONF library provides a consistant and flexable
|
|
interface to not only configuration files but also environment
|
|
variables.
|
|
|
|
But what about when something goes wrong?
|
|
The one advantage (and perhaps disadvantage) of all of these
|
|
functions being in one library was the ability to implement a
|
|
single error reporting system.
|
|
|
|
ERR This library is used to report errors. The error system records
|
|
library number, function number (in the library) and reason
|
|
number. Multiple errors can be reported so that an 'error' trace
|
|
is created. The errors can be printed in numeric or textual form.
|
|
|
|
|
|
==== ssluse.doc ========================================================
|
|
|
|
We have an SSL_CTX which contains global information for lots of
|
|
SSL connections. The session-id cache and the certificate verificate cache.
|
|
It also contains default values for use when certificates are used.
|
|
|
|
SSL_CTX
|
|
default cipher list
|
|
session-id cache
|
|
certificate cache
|
|
default session-id timeout period
|
|
New session-id callback
|
|
Required session-id callback
|
|
session-id stats
|
|
Informational callback
|
|
Callback that is set, overrides the SSLeay X509 certificate
|
|
verification
|
|
The default Certificate/Private Key pair
|
|
Default read ahead mode.
|
|
Default verify mode and verify callback. These are not used
|
|
if the over ride callback mentioned above is used.
|
|
|
|
Each SSL can have the following defined for it before a connection is made.
|
|
|
|
Certificate
|
|
Private key
|
|
Ciphers to use
|
|
Certificate verify mode and callback
|
|
IO object to use in the comunication.
|
|
Some 'read-ahead' mode information.
|
|
A previous session-id to re-use.
|
|
|
|
A connection is made by using SSL_connect or SSL_accept.
|
|
When non-blocking IO is being used, there are functions that can be used
|
|
to determin where and why the SSL_connect or SSL_accept did not complete.
|
|
This information can be used to recall the functions when the 'error'
|
|
condition has dissapeared.
|
|
|
|
After the connection has been made, information can be retrived about the
|
|
SSL session and the session-id values that have been decided apon.
|
|
The 'peer' certificate can be retrieved.
|
|
|
|
The session-id values include
|
|
'start time'
|
|
'timeout length'
|
|
|
|
|
|
|
|
==== stack.doc ========================================================
|
|
|
|
The stack data structure is used to store an ordered list of objects.
|
|
It is basically misnamed to call it a stack but it can function that way
|
|
and that is what I originally used it for. Due to the way element
|
|
pointers are kept in a malloc()ed array, the most efficient way to use this
|
|
structure is to add and delete elements from the end via sk_pop() and
|
|
sk_push(). If you wish to do 'lookups' sk_find() is quite efficient since
|
|
it will sort the stack (if required) and then do a binary search to lookup
|
|
the requested item. This sorting occurs automatically so just sk_push()
|
|
elements on the stack and don't worry about the order. Do remember that if
|
|
you do a sk_find(), the order of the elements will change.
|
|
|
|
You should never need to 'touch' this structure directly.
|
|
typedef struct stack_st
|
|
{
|
|
unsigned int num;
|
|
char **data;
|
|
int sorted;
|
|
|
|
unsigned int num_alloc;
|
|
int (*comp)();
|
|
} STACK;
|
|
|
|
'num' holds the number of elements in the stack, 'data' is the array of
|
|
elements. 'sorted' is 1 is the list has been sorted, 0 if not.
|
|
|
|
num_alloc is the number of 'nodes' allocated in 'data'. When num becomes
|
|
larger than num_alloc, data is realloced to a larger size.
|
|
If 'comp' is set, it is a function that is used to compare 2 of the items
|
|
in the stack. The function should return -1, 0 or 1, depending on the
|
|
ordering.
|
|
|
|
#define sk_num(sk) ((sk)->num)
|
|
#define sk_value(sk,n) ((sk)->data[n])
|
|
|
|
These 2 macros should be used to access the number of elements in the
|
|
'stack' and to access a pointer to one of the values.
|
|
|
|
STACK *sk_new(int (*c)());
|
|
This creates a new stack. If 'c', the comparison function, is not
|
|
specified, the various functions that operate on a sorted 'stack' will not
|
|
work (sk_find()). NULL is returned on failure.
|
|
|
|
void sk_free(STACK *);
|
|
This function free()'s a stack structure. The elements in the
|
|
stack will not be freed so one should 'pop' and free all elements from the
|
|
stack before calling this function or call sk_pop_free() instead.
|
|
|
|
void sk_pop_free(STACK *st; void (*func)());
|
|
This function calls 'func' for each element on the stack, passing
|
|
the element as the argument. sk_free() is then called to free the 'stack'
|
|
structure.
|
|
|
|
int sk_insert(STACK *sk,char *data,int where);
|
|
This function inserts 'data' into stack 'sk' at location 'where'.
|
|
If 'where' is larger that the number of elements in the stack, the element
|
|
is put at the end. This function tends to be used by other 'stack'
|
|
functions. Returns 0 on failure, otherwise the number of elements in the
|
|
new stack.
|
|
|
|
char *sk_delete(STACK *st,int loc);
|
|
Remove the item a location 'loc' from the stack and returns it.
|
|
Returns NULL if the 'loc' is out of range.
|
|
|
|
char *sk_delete_ptr(STACK *st, char *p);
|
|
If the data item pointed to by 'p' is in the stack, it is deleted
|
|
from the stack and returned. NULL is returned if the element is not in the
|
|
stack.
|
|
|
|
int sk_find(STACK *st,char *data);
|
|
Returns the location that contains a value that is equal to
|
|
the 'data' item. If the comparison function was not set, this function
|
|
does a linear search. This function actually qsort()s the stack if it is not
|
|
in order and then uses bsearch() to do the initial search. If the
|
|
search fails,, -1 is returned. For mutliple items with the same
|
|
value, the index of the first in the array is returned.
|
|
|
|
int sk_push(STACK *st,char *data);
|
|
Append 'data' to the stack. 0 is returned if there is a failure
|
|
(due to a malloc failure), else 1. This is
|
|
sk_insert(st,data,sk_num(st));
|
|
|
|
int sk_unshift(STACK *st,char *data);
|
|
Prepend 'data' to the front (location 0) of the stack. This is
|
|
sk_insert(st,data,0);
|
|
|
|
char *sk_shift(STACK *st);
|
|
Return and delete from the stack the first element in the stack.
|
|
This is sk_delete(st,0);
|
|
|
|
char *sk_pop(STACK *st);
|
|
Return and delete the last element on the stack. This is
|
|
sk_delete(st,sk_num(sk)-1);
|
|
|
|
void sk_zero(STACK *st);
|
|
Removes all items from the stack. It does not 'free'
|
|
pointers but is a quick way to clear a 'stack of references'.
|
|
|
|
==== threads.doc ========================================================
|
|
|
|
How to compile SSLeay for multi-threading.
|
|
|
|
Well basically it is quite simple, set the compiler flags and build.
|
|
I have only really done much testing under Solaris and Windows NT.
|
|
If you library supports localtime_r() and gmtime_r() add,
|
|
-DTHREADS to the makefile parameters. You can probably survive with out
|
|
this define unless you are going to have multiple threads generating
|
|
certificates at once. It will not affect the SSL side of things.
|
|
|
|
The approach I have taken to doing locking is to make the application provide
|
|
callbacks to perform locking and so that the SSLeay library can distinguish
|
|
between threads (for the error state).
|
|
|
|
To have a look at an example program, 'cd mt; vi mttest.c'.
|
|
To build under solaris, sh solaris.sh, for Windows NT or Windows 95,
|
|
win32.bat
|
|
|
|
This will build mttest which will fire up 10 threads that talk SSL
|
|
to each other 10 times.
|
|
To enable everything to work, the application needs to call
|
|
|
|
CRYPTO_set_id_callback(id_function);
|
|
CRYPTO_set_locking_callback(locking_function);
|
|
|
|
before any multithreading is started.
|
|
id_function does not need to be defined under Windows NT or 95, the
|
|
correct function will be called if it is not. Under unix, getpid()
|
|
is call if the id_callback is not defined, for Solaris this is wrong
|
|
(since threads id's are not pid's) but under Linux it is correct
|
|
(threads are just processes sharing the data segement).
|
|
|
|
The locking_callback is used to perform locking by the SSLeay library.
|
|
eg.
|
|
|
|
void solaris_locking_callback(mode,type,file,line)
|
|
int mode;
|
|
int type;
|
|
char *file;
|
|
int line;
|
|
{
|
|
if (mode & CRYPTO_LOCK)
|
|
mutex_lock(&(lock_cs[type]));
|
|
else
|
|
mutex_unlock(&(lock_cs[type]));
|
|
}
|
|
|
|
Now in this case I have used mutexes instead of read/write locks, since they
|
|
are faster and there are not many read locks in SSLeay, you may as well
|
|
always use write locks. file and line are __FILE__ and __LINE__ from
|
|
the compile and can be usefull when debugging.
|
|
|
|
Now as you can see, 'type' can be one of a range of values, these values are
|
|
defined in crypto/crypto.h
|
|
CRYPTO_get_lock_name(type) will return a text version of what the lock is.
|
|
There are CRYPTO_NUM_LOCKS locks required, so under solaris, the setup
|
|
for multi-threading can be
|
|
|
|
static mutex_t lock_cs[CRYPTO_NUM_LOCKS];
|
|
|
|
void thread_setup()
|
|
{
|
|
int i;
|
|
|
|
for (i=0; i<CRYPTO_NUM_LOCKS; i++)
|
|
mutex_init(&(lock_cs[i]),USYNC_THREAD,NULL);
|
|
CRYPTO_set_id_callback((unsigned long (*)())solaris_thread_id);
|
|
CRYPTO_set_locking_callback((void (*)())solaris_locking_callback);
|
|
}
|
|
|
|
As a final note, under Windows NT or Windows 95, you have to be careful
|
|
not to mix the various threaded, unthreaded and debug libraries.
|
|
Normally if they are mixed incorrectly, mttest will crash just after printing
|
|
out some usage statistics at the end. This is because the
|
|
different system libraries use different malloc routines and if
|
|
data is malloc()ed inside crypt32.dll or ssl32.dll and then free()ed by a
|
|
different library malloc, things get very confused.
|
|
|
|
The default SSLeay DLL builds use /MD, so if you use this on your
|
|
application, things will work as expected. If you use /MDd,
|
|
you will probably have to rebuild SSLeay using this flag.
|
|
I should modify util/mk1mf.pl so it does all this correctly, but
|
|
this has not been done yet.
|
|
|
|
One last warning. Because locking overheads are actually quite large, the
|
|
statistics collected against the SSL_CTX for successfull connections etc
|
|
are not locked when updated. This does make it possible for these
|
|
values to be slightly lower than they should be, if you are
|
|
running multithreaded on a multi-processor box, but this does not really
|
|
matter much.
|
|
|
|
|
|
==== txt_db.doc ========================================================
|
|
|
|
TXT_DB, a simple text based in memory database.
|
|
|
|
It holds rows of ascii data, for which the only special character is '\0'.
|
|
The rows can be of an unlimited length.
|
|
|
|
==== why.doc ========================================================
|
|
|
|
This file is more of a note for other people who wish to understand why
|
|
the build environment is the way it is :-).
|
|
|
|
The include files 'depend' as follows.
|
|
Each of
|
|
crypto/*/*.c includes crypto/cryptlib.h
|
|
ssl/*.c include ssl/ssl_locl.h
|
|
apps/*.c include apps/apps.h
|
|
crypto/cryptlib.h, ssl/ssl_locl.h and apps/apps.h
|
|
all include e_os.h which contains OS/environment specific information.
|
|
If you need to add something todo with a particular environment,
|
|
add it to this file. It is worth remembering that quite a few libraries,
|
|
like lhash, des, md, sha etc etc do not include crypto/cryptlib.h. This
|
|
is because these libraries should be 'independantly compilable' and so I
|
|
try to keep them this way.
|
|
e_os.h is not so much a part of SSLeay, as the placing in one spot all the
|
|
evil OS dependant muck.
|
|
|
|
I wanted to automate as many things as possible. This includes
|
|
error number generation. A
|
|
make errors
|
|
will scan the source files for error codes, append them to the correct
|
|
header files, and generate the functions to print the text version
|
|
of the error numbers. So don't even think about adding error numbers by
|
|
hand, put them in the form
|
|
XXXerr(XXXX_F_XXXX,YYYY_R_YYYY);
|
|
on line and it will be automatically picked up my a make errors.
|
|
|
|
In a similar vein, programs to be added into ssleay in the apps directory
|
|
just need to have an entry added to E_EXE in makefile.ssl and
|
|
everthing will work as expected. Don't edit progs.h by hand.
|
|
|
|
make links re-generates the symbolic links that are used. The reason why
|
|
I keep everything in its own directory, and don't put all the
|
|
test programs and header files in 'test' and 'include' is because I want
|
|
to keep the 'sub-libraries' independant. I still 'pull' out
|
|
indervidual libraries for use in specific projects where the code is
|
|
required. I have used the 'lhash' library in just about every software
|
|
project I have worked on :-).
|
|
|
|
make depend generates dependancies and
|
|
make dclean removes them.
|
|
|
|
You will notice that I use perl quite a bit when I could be using 'sed'.
|
|
The reason I decided to do this was to just stick to one 'extra' program.
|
|
For Windows NT, I have perl and no sed.
|
|
|
|
The util/mk1mf.pl program can be used to generate a single makefile.
|
|
I use this because makefiles under Microsoft are horrific.
|
|
Each C compiler seems to have different linker formats, which have
|
|
to be used because the retarted C compilers explode when you do
|
|
cl -o file *.o.
|
|
|
|
Now some would argue that I should just use the single makefile. I don't
|
|
like it during develoment for 2 reasons. First, the actuall make
|
|
command takes a long time. For my current setup, if I'm in
|
|
crypto/bn and I type make, only the crypto/bn directory gets rebuilt,
|
|
which is nice when you are modifying prototypes in bn.h which
|
|
half the SSLeay depends on. The second is that to add a new souce file
|
|
I just plonk it in at the required spot in the local makefile. This
|
|
then alows me to keep things local, I don't need to modify a 'global'
|
|
tables (the make for unix, the make for NT, the make for w31...).
|
|
When I am ripping apart a library structure, it is nice to only
|
|
have to worry about one directory :-).
|
|
|
|
Having said all this, for the hell of it I put together 2 files that
|
|
#include all the souce code (generated by doing a ls */*.o after a build).
|
|
crypto.c takes only 30 seconds to build under NT and 2 minutes under linux
|
|
for my pentium100. Much faster that the normal build :-).
|
|
Again, the problem is that when using libraries, every program linked
|
|
to libcrypto.a would suddenly get 330k of library when it may only need
|
|
1k. This technique does look like a nice way to do shared libraries though.
|
|
|
|
Oh yes, as a final note, to 'build' a distribution, I just type
|
|
make dist.
|
|
This cleans and packages everything. The directory needs to be called
|
|
SSLeay since the make does a 'cd ..' and renames and tars things up.
|
|
|
|
==== req.1 ========================================================
|
|
|
|
The 'req' command is used to manipulate and deal with pkcs#10
|
|
certificate requests.
|
|
|
|
It's default mode of operation is to load a certificate and then
|
|
write it out again.
|
|
|
|
By default the 'req' is read from stdin in 'PEM' format.
|
|
The -inform option can be used to specify 'pem' format or 'der'
|
|
format. PEM format is the base64 encoding of the DER format.
|
|
|
|
By default 'req' then writes the request back out. -outform can be used
|
|
to indicate the desired output format, be it 'pem' or 'der'.
|
|
|
|
To specify an input file, use the '-in' option and the '-out' option
|
|
can be used to specify the output file.
|
|
|
|
If you wish to perform a command and not output the certificate
|
|
request afterwards, use the '-noout' option.
|
|
|
|
When a certificate is loaded, it can be printed in a human readable
|
|
ascii format via the '-text' option.
|
|
|
|
To check that the signature on a certificate request is correct, use
|
|
the '-verify' option to make sure that the private key contained in the
|
|
certificate request corresponds to the signature.
|
|
|
|
Besides the default mode, there is also the 'generate a certificate
|
|
request' mode. There are several flags that trigger this mode.
|
|
|
|
-new will generate a new RSA key (if required) and then prompts
|
|
the user for details for the certificate request.
|
|
-newkey has an argument that is the number of bits to make the new
|
|
key. This function also triggers '-new'.
|
|
|
|
The '-new' option can have a key to use specified instead of having to
|
|
load one, '-key' is used to specify the file containg the key.
|
|
-keyform can be used to specify the format of the key. Only
|
|
'pem' and 'der' formats are supported, later, 'netscape' format may be added.
|
|
|
|
Finally there is the '-x509' options which makes req output a self
|
|
signed x509 certificate instead of a certificate request.
|
|
|
|
Now as you may have noticed, there are lots of default options that
|
|
cannot be specified via the command line. They are held in a 'template'
|
|
or 'configuration file'. The -config option specifies which configuration
|
|
file to use. See conf.doc for details on the syntax of this file.
|
|
|
|
The req command uses the 'req' section of the config file.
|
|
|
|
---
|
|
# The following variables are defined. For this example I will populate
|
|
# the various values
|
|
[ req ]
|
|
default_bits = 512 # default number of bits to use.
|
|
default_keyfile = testkey.pem # Where to write the generated keyfile
|
|
# if not specified.
|
|
distinguished_name= req_dn # The section that contains the
|
|
# information about which 'object' we
|
|
# want to put in the DN.
|
|
attributes = req_attr # The objects we want for the
|
|
# attributes field.
|
|
encrypt_rsa_key = no # Should we encrypt newly generated
|
|
# keys. I strongly recommend 'yes'.
|
|
|
|
# The distinguished name section. For the following entries, the
|
|
# object names must exist in the SSLeay header file objects.h. If they
|
|
# do not, they will be silently ignored. The entries have the following
|
|
# format.
|
|
# <object_name> => string to prompt with
|
|
# <object_name>_default => default value for people
|
|
# <object_name>_value => Automatically use this value for this field.
|
|
# <object_name>_min => minimum number of characters for data (def. 0)
|
|
# <object_name>_max => maximum number of characters for data (def. inf.)
|
|
# All of these entries are optional except for the first one.
|
|
[ req_dn ]
|
|
countryName = Country Name (2 letter code)
|
|
countryName_default = AU
|
|
|
|
stateOrProvinceName = State or Province Name (full name)
|
|
stateOrProvinceName_default = Queensland
|
|
|
|
localityName = Locality Name (eg, city)
|
|
|
|
organizationName = Organization Name (eg, company)
|
|
organizationName_default = Mincom Pty Ltd
|
|
|
|
organizationalUnitName = Organizational Unit Name (eg, section)
|
|
organizationalUnitName_default = MTR
|
|
|
|
commonName = Common Name (eg, YOUR name)
|
|
commonName_max = 64
|
|
|
|
emailAddress = Email Address
|
|
emailAddress_max = 40
|
|
|
|
# The next section is the attributes section. This is exactly the
|
|
# same as for the previous section except that the resulting objects are
|
|
# put in the attributes field.
|
|
[ req_attr ]
|
|
challengePassword = A challenge password
|
|
challengePassword_min = 4
|
|
challengePassword_max = 20
|
|
|
|
unstructuredName = An optional company name
|
|
|
|
----
|
|
Also note that the order that attributes appear in this file is the
|
|
order they will be put into the distinguished name.
|
|
|
|
Once this request has been generated, it can be sent to a CA for
|
|
certifying.
|
|
|
|
----
|
|
A few quick examples....
|
|
|
|
To generate a new request and a new key
|
|
req -new
|
|
|
|
To generate a new request and a 1058 bit key
|
|
req -newkey 1058
|
|
|
|
To generate a new request using a pre-existing key
|
|
req -new -key key.pem
|
|
|
|
To generate a self signed x509 certificate from a certificate
|
|
request using a supplied key, and we want to see the text form of the
|
|
output certificate (which we will put in the file selfSign.pem
|
|
req -x509 -in req.pem -key key.pem -text -out selfSign.pem
|
|
|
|
Verify that the signature is correct on a certificate request.
|
|
req -verify -in req.pem
|
|
|
|
Verify that the signature was made using a specified public key.
|
|
req -verify -in req.pem -key key.pem
|
|
|
|
Print the contents of a certificate request
|
|
req -text -in req.pem
|
|
|
|
==== danger ========================================================
|
|
|
|
If you specify a SSLv2 cipher, and the mode is SSLv23 and the server
|
|
can talk SSLv3, it will claim there is no cipher since you should be
|
|
using SSLv3.
|
|
|
|
When tracing debug stuff, remember BIO_s_socket() is different to
|
|
BIO_s_connect().
|
|
|
|
BSD/OS assember is not working
|
|
|