Tom Lane <tgl@sss.pgh.pa.us> writes:
> Christopher Kings-Lynne <chriskl@familyhealth.com.au> writes:
> > AndrewSN can't post at the moment, but asked me to post this for him:
> > "Knowing the md5 hash is enough to authenticate via the 'md5' method in
> > pg_hba.conf, even if you don't know the original password.
>
> If you know the md5 hash, you know everything the postmaster does, so
> it's hard to see where such an attacker is going to be stopped.
Eh? Just because you know everything the postmaster does doesn't mean you
can't be stopped. In the traditional unix password file scheme the crypt
string is public knowledge but it's not enough to log in. You need the
original password that crypts to that value.
> The entire point here is not to expose the cleartext password, and that
> really has nothing to do with whether you're going to break into the PG
> database. It's about protecting users who are foolish enough to use the same
> cleartext password for multiple services.
Well that's a fine goal but it's not as good as an authentication scheme that
doesn't store a password equivalent in the database.
--
greg