Thread: Re: pgsql: Allow 'sslkey' and 'sslcert' in postgres_fdw user mappings

On Thu, Jan 9, 2020 at 3:11 AM Andrew Dunstan <andrew@dunslane.net> wrote:
> Allow 'sslkey' and 'sslcert' in postgres_fdw user mappings
>
> This allows different users to authenticate with different certificates.
>
> Author: Craig Ringer
>
> https://git.postgresql.org/pg/commitdiff/f5fd995a1a24e6571d26b1e29c4dc179112b1003

Does this mean that a non-superuser can induce postgres_fdw to read an
arbitrary file from the local filesystem?

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company

Re: Robert Haas 2020-01-09 <CA+TgmoZEjyv_PD=2cinkbDA_chyLNAcBPL_9bKJQ6bc=nw+FHA@mail.gmail.com>
> Does this mean that a non-superuser can induce postgres_fdw to read an
> arbitrary file from the local filesystem?

Yes, see my comments in the "Allow 'sslkey' and 'sslcert' in
postgres_fdw user mappings" thread.

Christoph

On 1/20/20 2:48 AM, Craig Ringer wrote:
> On Thu, 9 Jan 2020 at 22:38, Christoph Berg <myon@debian.org
> <mailto:myon@debian.org>> wrote:
>
>     Re: Robert Haas 2020-01-09
>     <CA+TgmoZEjyv_PD=2cinkbDA_chyLNAcBPL_9bKJQ6bc=nw+FHA@mail.gmail.com
>     <mailto:nw%2BFHA@mail.gmail.com>>
>     > Does this mean that a non-superuser can induce postgres_fdw to
>     read an
>     > arbitrary file from the local filesystem?
>
>     Yes, see my comments in the "Allow 'sslkey' and 'sslcert' in
>     postgres_fdw user mappings" thread.
>
>
> Ugh, I misread your comment.
>
> You raise a sensible concern.
>
> These options should be treated the same as the proposed option to
> allow passwordless connections: disallow creation or alteration of FDW
> connection strings that use them by non-superusers. So a superuser can
> define a user mapping that uses these options, but normal users may not.
>
>


Already done.


cheers


andrew


-- 
Andrew Dunstan                https://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services