101 lines
3.3 KiB
Plaintext
101 lines
3.3 KiB
Plaintext
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One of the nice things of S/Key is that it still leaves you the option
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to use regular UNIX passwords. In fact, the presence of S/Key support
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is completely invisible for a user until she has set up a password with
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the keyinit command. You can permit regular UNIX passwords for local
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logins, while at the same time insisting on S/Key passwords for logins
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from outside.
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ORIGIN
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These files are modified versions of the s/key files found on
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thumper.bellcore.com at 21 oct 1993. They have been fixed to
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run on top of SunOS 4.1.3 and Solaris 2.3.
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Installation is described at the end of this file.
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USAGE
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Use the keyinit command to set up a new series of s/key passwords.
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wzv_6% keyinit
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Updating wietse:
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Old key: wz173500
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Reminder - Only use this method if you are direct connected.
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If you are using telnet or dial-in exit with no password and use keyinit -s.
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Enter secret password:
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Again secret password:
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ID wietse s/key is 99 wz173501
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BLAH BLA BLAH BLAH BLAH BLA
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Be sure to make your secret password sufficiently long. Try using a
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full sentence instead of just one single word.
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You will have to do a "keyinit" on every system that you want to login
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on using one-time passwords.
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Whenever you log into an s/key protected system you will see
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something like:
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login: wietse
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s/key 98 wz173501
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Password:
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In this case you can either enter your regular UNIX password or
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your one-time s/key password. For example, I open a local window
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to compute the password:
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local% key 98 wz173501
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Reminder - Do not use key while logged in via telnet or rlogin.
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Enter secret password:
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BLAH BLA BLAH BLAH BLAH BLA
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The "BLAH BLA BLAH BLAH BLAH BLA" is the one-time s/key password.
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If you have to type the one-time password in by hand, it is convenient
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to have echo turned on so that you can correct typing errors. Just type
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a newline at the "Password:" prompt:
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login: wietse
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s/key 98 wz173501
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Password: (turning echo on)
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Password:BLAH BLA BLAH BLAH BLAH BLA
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The 98 in the challenge will be 97 the next time, and so on. You'll get
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a warning when you are about to run out of s/key passwords, so that you
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will have to run the keyinit command again.
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Sometimes it is more practical to carry a piece of paper with a small
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series of one-time passwords. You can generate the list with:
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% key -n 10 98 wz173501
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98: BLAH BLA BLAH BLAH BLAH BLA
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97: ...
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96: ...
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Be careful when printing material like this!
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INSTALLATION
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To install, do: make sunos4 (or whatever), then: make install.
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The UNIX password is always permitted with non-network logins. By
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default, UNIX passwords are always permitted (the Bellcore code by
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default disallows UNIX passwords but I think that is too painful). In
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order to permit UNIX passwords only with logins from specific networks,
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create a file /etc/skey.access. For example,
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# First word says if UNIX passwords are to be permitted or denied.
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# remainder of the rule is a networknumber and mask. A rule matches a
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# host if any of its addresses satisfies:
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#
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# network = (address & mask)
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#
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#what network mask
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permit 131.155.210.0 255.255.255.0
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deny 0.0.0.0 0.0.0.0
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This particular example will permit UNIX passwords with logins from any
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host on network 131.155.210, but will insist on one-time passwords in
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all other cases.
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