Re: Roles with empty password (probably bug in libpq and in psql as well).

2012/7/24 Guillaume Lelarge <guillaume(at)lelarge(dot)info>

> On Tue, 2012-07-24 at 17:36 +0400, Dmitriy Igrishin wrote:
> > Hey Guillaume,
> >
> > 2012/7/24 Guillaume Lelarge <guillaume(at)lelarge(dot)info>
> > On Tue, 2012-07-24 at 16:41 +0400, Dmitriy Igrishin wrote:
> > > Hey all,
> > >
> > > According to
> > http://www.postgresql.org/docs/9.2/static/sql-alterrole.html
> > >
> > > A query:
> > > ALTER ROLE davide WITH PASSWORD NULL;
> > > removes a role's password.
> > >
> > > But it's impossible to pass empty (NULL) password to the
> > backend
> > > by using libpq, because connectOptions2() defined the
> > fe-connect.c
> > > reads a password from the ~/.pgpass even when a password
> > > specified as an empty string literal ("").
> > >
> > > Also, when connecting to the server via psql(1) by using a
> > role
> > > with removed password psql exists with status 2 and prints
> > the error
> > > message:
> > > psql: fe_sendauth: no password supplied
> > >
> >
> >
> > Yes, and? I don't see how this could be a bug. If your
> > authentication
> > method asks for a password, you need to have one.
> > Yes, I need. I just want to have empty password ("").
> >
> > If you have resetted
> > it, well, you shouldn't have. Or you really want that your
> > users could
> > connect without a password, and then you need to change your
> > authentication method with trust. But no-one will encourage
> > you to do
> > that.
> > Why I need to change an auth. method? If I've used a \password command
> > in psql(1) and specified an empty password for my role I need to ask
> > a database admin to change an auth. method? :-) Cool!
> > Please note, psql(1) allow to do it as well as SQL - too.
> >
>
> If your admin sets PostgreSQL so that a password needs to be given while
> trying to connect, a "simple user" shouldn't be able to bypass that by
> setting no password for his role.
>

> So, yes, if you want to be able to not use a password, you need to
> change your authentification method.
>
dmitigr=> CREATE USER test ENCRYPTED PASSWORD 'test';
CREATE ROLE
dmitigr=> \c dmitigr test
Password for user test:
You are now connected to database "dmitigr" as user "test".
dmitigr=> \password
Enter new password:
Enter it again:

Now the user "test" will not be able to connect to the server.
This behaviour is incorrect.

--
// Dmitriy.