From: Tom Lane <tgl@sss.pgh.pa.us>
To: Nathan Bossart <nathandbossart@gmail.com>
cc: Alexander Lakhin <exclusion@gmail.com>,
        pgsql-hackers <pgsql-hackers@postgresql.org>
Subject: Re: Should rolpassword be toastable?
In-reply-to: <ZuydAj4nrt4cpGU5@nathan>
References: <89e8649c-eb74-db25-7945-6d6b23992394@gmail.com> <1284094.1695479962@sss.pgh.pa.us> <67793ae1-3adc-a6e0-0bb3-c23a28c0627a@gmail.com> <a9524f94-316c-349a-6e4d-79b878706f82@gmail.com> <Zuwzp09o9uiG0f0F@nathan> <1986859.1726756275@sss.pgh.pa.us> <ZuxjAIOJ4GSa34KC@nathan> <ZuydAj4nrt4cpGU5@nathan>
Comments: In-reply-to Nathan Bossart <nathandbossart@gmail.com>
	message dated "Thu, 19 Sep 2024 16:52:02 -0500"
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Date: Thu, 19 Sep 2024 18:14:34 -0400
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Nathan Bossart <nathandbossart@gmail.com> writes:
> Oh, actually, I see that we are already validating the hash, but you can
> create valid SCRAM-SHA-256 hashes that are really long.  So putting an
> arbitrary limit (patch attached) is probably the correct path forward.  I'd
> also remove pg_authid's TOAST table while at it.

Shouldn't we enforce the limit in every case in encrypt_password,
not just this one?  (I do agree that encrypt_password is an okay
place to enforce it.)

I think you will get pushback from a limit of 256 bytes --- I seem
to recall discussion of actual use-cases where people were using
strings of a couple of kB.  Whatever the limit is, the error message
had better cite it explicitly.

Also, the ereport call needs an errcode.
ERRCODE_PROGRAM_LIMIT_EXCEEDED is probably suitable.

			regards, tom lane