On Wed, Feb 11, 2015 at 3:26 PM, Robert Haas <robertmh...@gmail.com> wrote:
> On Wed, Feb 11, 2015 at 9:14 AM, Magnus Hagander <mag...@hagander.net> > wrote: > > On Wed, Feb 11, 2015 at 3:10 PM, José Luis Tallón > > <jltal...@adv-solutions.net> wrote: > >> > >> On 02/11/2015 02:31 PM, Magnus Hagander wrote: > >> > >> > >>> In any case, my larger point was that given the pain that we're going > to > >>> incur here, and the certainly years-long transition interval involved, > >>> it would be foolish to think only about replacing the MD5 algorithm and > >>> not about reconsidering the context we use it in. Stuff like > >>> unreasonably > >>> short salt values should be dealt with at the same time. > >> > >> > >> > >> All discussion seems to be about the protocol, which is also the harder > >> problem, isn't it? > >> > >> ISTM that the more *important* thing to fix is the on-disk storage in > >> pg_authid. > >> > >> > >> At least, looks like it would be the most urgent (and with no need for > >> clients breaking in the process, AFAICT) > >> > >> [snip] > >> Seems the risk of someone either lifting pg_authid from disk or by > hacking > >> the system and being postgres, thereby accessing passwords stored > somewhere > >> else, is actually the bigger problem. But also one that should be > reasonably > >> easy (TM) to fix in a backwards compatible way? (just rewrite with a new > >> hash whenever the password is changed, but keep reading md5 until they > are > >> all replaced. > >> > >> > >> Adding a new system column with a text or enum representing the > algorithm > >> that created the "hash" would go a lot towards fixing this situation. > >> When/If the column isn't there, just assume "md5". This would allow for > >> transparent pg_upgrade. > > > > > > The hash value in pg_authid already contains "md5" as a prefix. No need > for > > another column. > > How do we distinguish that from a password that actually starts with md5? > > You mean one stored in cleatext? I don't know offhand :) If it's actually stored with md5 (which it really should be) it's still the hash, but prefixed with the constant md5. -- Magnus Hagander Me: http://www.hagander.net/ Work: http://www.redpill-linpro.com/
