Tom Lane wrote:
> BTW, I just thought of a small improvement to your patch that eliminates
> some of the ugliness. Suppose that when we recognize an attempt to
> connect as a global user (ie, feature flag is on and last character of
> username is '@'), we strip off the '@' before proceeding. Then we would
> have:
> global users appear in pg_shadow as foo
> local users appear in pg_shadow as foo@db
> and what this would mean is that you can flip between feature-enabled
> and feature-disabled states without breaking your global logins. So you
> don't need the extra step of creating a "postgres@" before turning on
> the feature. (Which was pretty ugly anyway, since even though postgres@
> could be made a superuser, he wouldn't be the same user as postgres ---
> this affects table ownership, for example, and would be a serious issue
> if you wanted any non-superuser global users.)
>
> I suppose some might argue that having to say postgres@ to log in,
> when your username is really just postgres as far as you can see in the
> database, is a tad confusing. But the whole thing is an acknowledged
> wart anyway, and I think getting rid of the two problems mentioned above
> is worth it.
Sure. If I can get one more 'yes' I will submit a new patch with the
change. It does prevent the namespace collision without mucking up
pg_shadow. We only need to tell people that global users need to supply
their username to the client as user@. Is that cleaner?
> Also, if we do this then it's important to strip a trailing '@' only
> if it's the *only* one in the given username. Else a local user
> 'foo@db1' could cheat to log into db2 by saying username = 'foo@db1@'
> with requested database db2. But I can't see any other security hole.
Ewe, I didn't think of that. Good point.
-- Bruce Momjian | http://candle.pha.pa.us pgman@candle.pha.pa.us | (610)
359-1001+ If your life is a hard drive, | 13 Roberts Road + Christ can be your backup. | Newtown Square,
Pennsylvania19073
