Re: dblink connection security

Tom Lane wrote:
> Here's a straw-man proposal that we could perhaps do for 8.3:
>
> 1. Invent a libpq connection-status function
>
> bool PQconnectionUsedPassword(const PGconn *conn);
>
> This returns true if the server had demanded a password during the
> authentication phase. Aside from solving the immediate problem, this
> can be useful for regular clients such as psql: it could be applied to a
> failed connection object to decide whether to prompt for a password
> (replacing the current egregious hack of strcmp'ing the error message).
>
> 2. Make dblink close the connection and throw error if called by a
> non-superuser and PQconnectionUsedPassword returns false.

Attached patch implements this proposal, including documentation
changes. I'll work separately on the back-branch version.

Any comments/objections?

Joe