Re: better page-level checksums

From: Bruce Momjian <bruce(at)momjian(dot)us>
To: Robert Haas <robertmhaas(at)gmail(dot)com>
Cc: Matthias van de Meent <boekewurm+postgres(at)gmail(dot)com>, PostgreSQL Hackers <pgsql-hackers(at)lists(dot)postgresql(dot)org>
Subject: Re: better page-level checksums
Date: 2022-06-16 23:24:43
Views: Raw Message | Whole Thread | Download mbox | Resend email
Lists: pgsql-hackers

On Tue, Jun 14, 2022 at 01:42:55PM -0400, Robert Haas wrote:
> Hmm, but on the other hand, if you imagine a scenario in which the
> "storage system extra blob" is actually a nonce for TDE, you need to
> be able to find it before you've decrypted the rest of the page. If
> pd_checksum gives you the offset of that data, you need to exclude it
> from what gets encrypted, which means that you need encrypt three
> separate non-contiguous areas of the page whose combined size is
> unlikely to be a multiple of the encryption algorithm's block size.
> That kind of sucks (and putting it at the end of the page makes it way
> better).

I continue to believe that a nonce is not needed for XTS encryption
mode, and that adding a tamper-detection GCM hash is of limited
usefulness since malicious writes can be done to other critical files
and can be used to find the cluster or encryption keys

Bruce Momjian <bruce(at)momjian(dot)us>

Indecision is a decision. Inaction is an action. Mark Batterson

In response to

Browse pgsql-hackers by date

  From Date Subject
Next Message Andres Freund 2022-06-16 23:31:30 PG 15 (and to a smaller degree 14) regression due to ExprEvalStep size
Previous Message Mark Wong 2022-06-16 22:56:50 Re: real/float example for testlibpq3