Re: [GENERAL] SHA1 on postgres 8.3

On Thu, Apr 03, 2008 at 07:07:56PM +0200, Svenne Krap wrote:
> I currently save only md5(id || username || 'password')*  into password, 
> if I had access to sha1 (for example) i would add another password 
> column so, having for example
> 
> ID serial
> Username varchar
> Password_md5 varchar
> Password_sha1 varchar
> 
> No matter how you see it, I get more bits of hash to check against.

Are you a cryptanalyst and are you sure that this doesn't actually make
things worse?  I'm sure it gives you a warm fuzzy feeling that it's
*got* to be better, but unless someone has done some hard maths I'm not
sure how you can be so sure.

Why not just use SHA-512, you get many more quality bits that way.

> I would drop md5 totally and use sha1 and ripemd-160 if possible.. but 
> currently i use only md5 as it is the only available one..  Loading 
> pgcrypto is overkill for something as simple as hash-functions.

Sounds like a good reason for moving the current md5 function out into
pgcrypto as well! :)

> * I prepend the id and the username to guard users with weak passwords 
> against known hashvalues (rainbow tables) should the box ever get 
> comprised ... 

I take it your threat model doesn't include the attacker logging
incoming queries to look for the clear-text password.

 Sam