The way Secure RPC is set up, the ecb_crypt() routine is expected to
be able to encrypt a buffer of any size up to 8192 bytes. However, the
des_ecb_encrypt() routine in libdes only encrypts 8 bytes (64 bits) at a
time. The rpc_enc.c module should compensate for this by calling
des_ecb_encrypt() repeatedly until it has encrypted the entire supplied
buffer, but it does not do this.
As a workaround, keyserv now handles this itself: if we're using DES
encryption, and the caller requested ECB mode, keyserv will do the right
thing.
Also changed all references to 'rc4' into 'arcfour' just in case some
litigious bastard from RSA is watching.
Note that I discovered and fixed this problem while trying to get
a part of NIS+ working: rpc.nisd signs directory objects with a 16-byte
MD5 digest that is encrypted with ecb_crypt(). Previously, only the
first 8 bytes of the digest were being properly encrypted, which caused
the Sun nis_cachemgr to reject the signatures as invalid. I failed to
notice this before since Secure RPC usually never has to encrypt more
than 8 bytes of data during normal operations.
This version supports both the keyserv v1 and v2 protocols. It uses the
new AF_LOCAL transport so that only local processes can use it for
storing/retrieving keys, and it uses the SCM_CREDS kernel hack for
authentication. With these two modifications, we don't need the keyenvoy
program normally used with RPC 4.0.
Note that if libdes.so.3.x is present on the system when keyserv
is started, Secure RPC will run with normal DES encryption. If not,
everything falls back to RC4 with a 40 bit key.
