Horton

Re: storing an explicit nonce

Ants Aasma <ants@cybertec.at>

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From: Ants Aasma <ants@cybertec.at>
To: Stephen Frost <sfrost@snowman.net>
Cc: Bruce Momjian <bruce@momjian.us>, Sasasu <i@sasa.su>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Date: 2021-10-07T18:59:31Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. Rethink method for assigning OIDs to the template0 and postgres DBs.

  2. pg_upgrade: Preserve database OIDs.

  3. pg_upgrade: Preserve relfilenodes and tablespace OIDs.

  4. Fix for new Boolean node

  5. Improve error handling of HMAC computations

  6. Add macro RelationIsPermanent() to report relation permanence

  7. Enhance nbtree index tuple deletion.

On Thu, 7 Oct 2021 at 21:52, Stephen Frost <sfrost@snowman.net> wrote:

> With XTS this isn't actually the case though, is it..?  Part of the
> point of XTS is that the last block doesn't have to be a full 16 bytes.
> What you're saying is true for XEX, but that's also why XEX isn't used
> for FDE in a lot of cases, because disk sectors aren't typically
> divisible by 16.
>
> https://en.wikipedia.org/wiki/Disk_encryption_theory
>
> Assuming that's correct, and I don't see any reason to doubt it, then
> perhaps it would make sense to have the LSN be unencrypted and include
> it in the tweak as that would limit the risk from re-use of the same
> tweak over time.
>

Right, my thought was to leave the first 8 bytes of pages, the LSN,
unencrypted and include the value in the tweak. Just tested that OpenSSL
aes-256-xts handles non multiple-of-16 messages just fine.

-- 

Ants Aasma
Senior Database Engineerwww.cybertec-postgresql.com