Re: Encrypting pg_shadow passwords - Mailing list pgsql-hackers

> On Mon, Jun 25, 2001 at 11:27:42PM -0400, Bruce Momjian wrote:
> > I am replying to the original message because it has all the relevant
> > information.  The problem with 'password' authentication is that the
> > password goes across the wire in plaintext.  Now, if we start to ship
> > encrypted passwords across the wire, but use the same salt for every
> > authentication request, we are really no more secure than if we sent it
> > in the clear.
> >
> > If a user specifies 'crypt' in pg_hba.conf, they should be assured that
> > the password is safe in case someone snoops it.  Encrypting pg_shadow
> > and comparing that with the same salt every time is not secure from
> > snooping so we don't allow it.
> > 
> > Am I missing something?
> 
> i don't disagree that sending plaintext across the wire, if possible, it
> should be avoided.
> 
> however, i look at it this way.
> 
> many _existing_ implementations send plaintext across the wire, telnet,
> ftp, .htaccess, imap and pop (non-ssl).
> 
> i would much rather risk a single plain-text password being snooped on the
> wire, rather than having an entire database of plain-text passwords for
> someone to scoop.
> 
> many people re-use passwords for multiple purposes, thus reducing the bio-core
> required to keep track of a bazillion passwords.
> 
> in my opinion, storing plain-text passwords in any media is just plain wrong,
> and a far greater security risk than having a password sniffed.
> 
> in my applications, i have SSL covering the client->app (browser->PHP code),
> so the sniffing would need to be on the wire from the app-server -> database
> server, which in many cases is the same machine.
> 
> my mods don't alter the operation of the server in any respect.
> 
> they do, however, allow people the choice of using a traditional
> telnetd/binlogin authentication scheme without resorting to external password
> files.

OK, I get you now.  Why not ask the client to do a crypt and compare
that to pg_shadow.  It is better than what we have now for 'password'
authentication because it encrypts pg_shadow.

The big problem is that you can't do 'crypt' authentication once you
encrypt pg_shadow, unless we do the double-encription thing, and I think
it is a bigger win for them to use crypt-authentication than to encrypt
pg_shadow.  The wire is clearly less secure than pg_shadow.

--  Bruce Momjian                        |  http://candle.pha.pa.us pgman@candle.pha.pa.us               |  (610)
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