Ovid,

I would argue that having a static salt is bad no matter where it is (with the password or seperated and stored someplace). Just as the salt is useful in avoiding collisions, that same property is useful in preventing dictionary attacks. If a bad guy knows the static salt, he would then need to only one-way hash his dictionary once with the static salt. Then it's just a matter of strcmp'ing the hashed dictionary with the hashed password. With a pseudo-random salt, things become a little more difficult (but not impossible), the bad guy now needs to have X number of hashed dictionaries where X is the range of your pseudo-random salt. Granted, it's still feasible to try and brute force crack a password but given the poor choices most people use for passwords, a dictionary attack is more useful.

So I would conclude storage of the salt is a way secondary issue to having a really good pseudo-random number generator and a salt that provides a large yet feasible domain.

-derby

In reply to Re: Too Convenient Security? by derby
in thread Too Convenient Security? by Ovid

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