From: Jan Wieck <janwieck@Yahoo.com>
To: CMVV <cmvilaverde@mail.telepac.pt>
Cc: pgsql-interfaces@postgreSQL.org
Subject: Re: pl/perl and security
Date: Thu, 8 Feb 2001 07:10:08 -0500 (EST)
Message-ID: <200102081210.HAA03543@jupiter.greatbridge.com> (raw)
In-Reply-To: <95otpc$hj4$1@news.tht.net>
CMVV wrote:
> Hi,
>
> I have discovered that in pl/perl we cannot make use of file handling.
> The README file in ../pl/plperl give us an hint with an example of a
> badfunc().
> What are the security reasons to do so, since with postgresql extensions
> (functions) written in C language we can do anything with flat files ?
> Can this security issue with pl/perl be overrided ?
> If so, how can i hack it ?
> It will be so nice to manage files from server-based functions written in
> pl/perl.
> Thanx
The security issue is that PL/Perl is designed to be a
trusted procedural language. Meaning, any unprivileged user
can create functions in it. Having file access, which is done
under the UNIX-userid running the postmaster process, any
user could modify your pg_hba.conf ...
The same applies for PL/Tcl, why there will be an untrusted
PL/TclU in 7.1, where only DB superusers can define functions
in it.
I'm not a Perl guy, but AFAIK you can modify the command mask
used for the perl interpreter in the PL handler. But be sure
to restrict your patched version of PL/Perl to superusers, or
accept that you created a big security hole.
Jan
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To: pgsql-interfaces@postgresql.org
Cc: janwieck@Yahoo.com, cmvilaverde@mail.telepac.pt
Subject: Re: pl/perl and security
In-Reply-To: <200102081210.HAA03543@jupiter.greatbridge.com>
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