UNIX MD5 CRYPT

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5 comments, last by nes8bit 22 years, 5 months ago
What is the difference between MD5 and UNIX MD5 CRYPT? What is the salt parameter for? --------------------------------------------- My useless posts have been viewed gotta view images to view the couNter times TIM: God@totalim.com
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I have no idea what the UNIX MD5 CRYPT is... I''d think they''d be the same thing though seeing as MD5 is an algorithm and all...

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Commander M
http://www.usenix.org/events/usenix99/provos/provos_html/node10.html

The crypt() function on *nix systems takes two parameters, the word to encrypt and a two-byte salt, and returns an encrypted string. The function traditionally uses the DES algorithm, which is perturbed one of 4096 ways based on the salt. The MD5 crypt was designed for FreeBSD because of export restrictions on encryption software and to allow for longer passwords. The actual salt you provide it has no effect on the actual hash the MD5 part generates (according to the above page); apparently it''s just concatenated into the result. In any case, MD5 is a standard algorithm; the "UNIX MD5 crypt" refers the the UNIX crypt() function (or crypt executable) that''s built to use MD5 rather than DES.

Gaah!
So tell me scott, how do I use it?

...you know why I''m asking also...

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My useless posts have been viewed gotta view images to view the couNter times
TIM: God@totalim.com
it's actually no more secure than a normal MD5 encryption scheme... if I remember its output is like this:

$(version)$(salt)$(MD5 hash)

so, for example:

$1$sa$a0b2c3d4e5f6a0b2c3d4e5f6

EDIT: Notice that the last part might be actual byte values rather than a hex representation of the hash. I'd have to play around with an actual implementation to check this.

Not really much more secure at all, I don't think. Remember, the UNIX MD5 CRYPT is an application of MD5 for encrypting/hashing passwords, it's not a new algorithm that's any more secure than MD5.

Gaah!

Edited by - SHilbert on November 6, 2001 3:01:13 PM
Is someone making a yahoo messenger client?

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good question

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My useless posts have been viewed gotta view images to view the couNter times
TIM: God@totalim.com

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