[REBOL] Re: From the Crypt
From: holger:rebol at: 28-Aug-2001 16:00
On Tue, Aug 28, 2001 at 02:25:55PM -0700, Ryan Cole wrote:
> Worst case, here is a link to the source:
>
> http://www.ecst.csuchico.edu/~atman/Crypto/code/crypt-c.html
That does not look like the source code to crypt(). I don't see the
function crypt() in it anywhere, and the method seems all wrong.
The exact implementation of crypt() varies widely across Unix versions.
The most common variant uses DES with a fixed "cleartext" and a variable
key
for one-way encryption. This is what programs that transfer
crypt()ed passwords across TCP links (e.g. CVS) usually use.
There are variations on the length and kind of "salt" used for that.
One other variation of crypt() use MD5, another one uses a combination
of base-64 encoding, Blowfish and ARCFOUR. Most Unix versions have
kernel options or other flags to enable one of these different methods
for their password database.
REBOL/Command supports all of these algorithms, so it should be possible
to use REBOL/Command to encrypt data in a compatible manner. Decryption
is impossible because of the one-way nature of crypt().
One source of Unix encryption C source code (crypt() and others) is
/pub/OpenBSD/src/lib/libc/crypt
on "ftp.openbsd.org".
--
Holger Kruse
[holger--rebol--com]
