Date: Thu, 15 Apr 2021 18:40:04 -0700
From: Noah Misch <noah@leadboat.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Robert Haas <robertmhaas@gmail.com>,
	PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>,
	Peter Eisentraut <peter.eisentraut@enterprisedb.com>
Subject: Re: Converting contrib SQL functions to new style
Message-ID: <20210416014004.GA1365702@rfd.leadboat.com>
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On Wed, Apr 14, 2021 at 02:03:56PM -0400, Tom Lane wrote:
> Robert Haas <robertmhaas@gmail.com> writes:
> > On Wed, Apr 14, 2021 at 1:41 PM Tom Lane <tgl@sss.pgh.pa.us> wrote:
> >> Could we hack things so that extension scripts are only allowed to
> >> reference objects created (a) by the system, (b) earlier in the
> >> same script, or (c) owned by one of the declared prerequisite
> >> extensions?  Seems like that might provide a pretty bulletproof
> >> defense against trojan-horse objects, though I'm not sure how much
> >> of a pain it'd be to implement.

Good idea.

> > That doesn't seem like a crazy idea, but the previous idea of having
> > some magic syntax that means "the schema where extension FOO is" seems
> > like it might be easier to implement and more generally useful.
> 
> I think that's definitely useful, but it's not a fix for the
> reference-capture problem unless you care to assume that the other
> extension's schema is free of trojan-horse objects.

I could see using that, perhaps in a non-SQL-language function.  I agree it
solves different problems.