Re: pg_hba.conf host name wildcard support

Peter Eisentraut <peter_e@gmx.net> writes:
> So, as previously indicated, let's add some wildcard support to the
> pg_hba.conf host name feature.  After looking around a bit, two syntaxes
> appear to be on offer:

> 1. TCP Wrappers style, leading dot indicates suffix match.
> So .example.com matches anything.example.com.  Not sure how useful that
> would be, but it could be implemented in about 3 lines of code.

> 2. Full regular expressions.  I'd suggest the pg_ident.conf style, where
> a leading slash indicates a regex.  An example could be /^dbserver\d\.
> With some code refactoring, this would also only take a few extra lines
> of code.

I'd lean to #1 myself.  Regexes would be a perpetual foot-gun because
(a) dot is a metacharacter to a regex and (b) a non-anchored pattern
is default but would be insecure in most usages.

There is a SQL-ish solution to those two objections: use LIKE or SIMILAR
TO pattern language not standard regex.  But #1 would be far more
familiar to most admin types.
        regards, tom lane