From: Tom Lane <tgl@sss.pgh.pa.us>
To: Daniel Gustafsson <daniel@yesql.se>
cc: Aleksander Alekseev <aleksander@timescale.com>,
        Postgres hackers <pgsql-hackers@lists.postgresql.org>,
        Bowen Shi <zxwsbg12138@gmail.com>
Subject: Re: [PATCH] Add CHECK_FOR_INTERRUPTS in scram_SaltedPassword loop.
In-reply-to: <C4DE43E8-AEC6-4ED2-8520-01C490F751AC@yesql.se>
References: <CAM_vCueV6xfr08KczfaCEk5J_qeTZtgqN7+orkNLx=g+phE82Q@mail.gmail.com> <CAJ7c6TMdDdC5f1qmS=UVx22Bvjqz=PhY=aeefwoXxGc_bK+WKQ@mail.gmail.com> <C4DE43E8-AEC6-4ED2-8520-01C490F751AC@yesql.se>
Comments: In-reply-to Daniel Gustafsson <daniel@yesql.se>
	message dated "Wed, 22 Nov 2023 14:59:07 +0100"
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Date: Wed, 22 Nov 2023 10:04:07 -0500
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Daniel Gustafsson <daniel@yesql.se> writes:
>> On 22 Nov 2023, at 14:30, Aleksander Alekseev <aleksander@timescale.com=
> wrote:
>> It sort of makes sense. I wonder though if we should limit the maximum
>> number of iterations instead. If somebody specified 1_000_000+
>> iteration this could also indicate a user error.

> I don't think it would be useful to limit this at an arbitrary point, it=
eration
> count can be set per password and if someone want a specific password to=
 be
> super-hard to brute force then why should we limit that?

Maybe because it could be used to construct a DOS scenario?  In
particular, since CHECK_FOR_INTERRUPTS doesn't work on the frontend
side, a situation like this wouldn't be interruptible there.

I agree with Aleksander that such cases are much more likely to
indicate user error than anything else.

			regards, tom lane