pg.ddx.io  pgsql-committers@postgresql.org mailing list archive  
help / color / mirror / Atom feed
From: Nathan Bossart <nathan@postgresql.org>
To: pgsql-committers@lists.postgresql.org
Subject: pgsql: Restrict password hash length.
Date: Mon, 07 Oct 2024 15:56:59 +0000
Message-ID: <E1sxq6V-002ZDJ-Go@gemulon.postgresql.org> (raw)

Restrict password hash length.

Commit 6aa44060a3 removed pg_authid's TOAST table because the only
varlena column is rolpassword, which cannot be de-TOASTed during
authentication because we haven't selected a database yet and
cannot read pg_class.  Since that change, attempts to set password
hashes that require out-of-line storage will fail with a "row is
too big" error.  This error message might be confusing to users.

This commit places a limit on the length of password hashes so that
attempts to set long password hashes will fail with a more
user-friendly error.  The chosen limit of 512 bytes should be
sufficient to avoid "row is too big" errors independent of BLCKSZ,
but it should also be lenient enough for all reasonable use-cases
(or at least all the use-cases we could imagine).

Reviewed-by: Tom Lane, Jonathan Katz, Michael Paquier, Jacob Champion
Discussion: https://postgr.es/m/89e8649c-eb74-db25-7945-6d6b23992394%40gmail.com

Branch
------
master

Details
-------
https://git.postgresql.org/pg/commitdiff/8275325a06ed91c053e046422a193dc6d56a70c5

Modified Files
--------------
src/backend/libpq/crypt.c              | 60 ++++++++++++++++++++++++----------
src/include/libpq/crypt.h              | 10 ++++++
src/test/regress/expected/password.out |  7 ++++
src/test/regress/sql/password.sql      |  4 +++
4 files changed, 63 insertions(+), 18 deletions(-)



Message-ID: <E1sxq6V-002ZDJ-Go@gemulon.postgresql.org>
Permalink:  ../E1sxq6V-002ZDJ-Go@gemulon.postgresql.org/
Also on:    postgresql.org/message-id/E1sxq6V-002ZDJ-Go@gemulon.postgresql.org

 · 

reply

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Reply to all the recipients using the --to and --cc options:
  reply via email

  To: pgsql-committers@postgresql.org
  Cc: nathan@postgresql.org, pgsql-committers@lists.postgresql.org
  Subject: Re: pgsql: Restrict password hash length.
  In-Reply-To: <E1sxq6V-002ZDJ-Go@gemulon.postgresql.org>

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox