Horton

Re: [Proposal] Table-level Transparent Data Encryption (TDE) and Key Management Service (KMS)

Joe Conway <mail@joeconway.com>

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From: Joe Conway <mail@joeconway.com>
To: Stephen Frost <sfrost@snowman.net>, Bruce Momjian <bruce@momjian.us>
Cc: Masahiko Sawada <sawada.mshk@gmail.com>, Tomas Vondra <tomas.vondra@2ndquadrant.com>, Robert Haas <robertmhaas@gmail.com>, Antonin Houska <ah@cybertec.at>, Haribabu Kommi <kommi.haribabu@gmail.com>, "Moon, Insung" <Moon_Insung_i3@lab.ntt.co.jp>, Ibrar Ahmed <ibrar.ahmad@gmail.com>, PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2019-07-08T22:24:40Z
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. Revamp the WAL record format.

On 7/8/19 6:04 PM, Stephen Frost wrote:
> * Bruce Momjian (bruce@momjian.us) wrote:
>> Uh, well, renaming the user was a big problem, but that is the only case
>> I can think of.  I don't see that as an issue for block or WAL sequence
>> numbers.  If we want to use a different nonce, we have to find a way to
>> store it or look it up efficiently.  Considering the nonce size, I don't
>> see how that is possible.
> 
> No, this also meant that, as an attacker, I *knew* the salt ahead of
> time and therefore could build rainbow tables specifically for that
> salt.  I could also use those *same* tables for any system where that
> user had an account, even if they used different passwords on different
> systems...
> 
> I appreciate that *some* of this might not be completely relevant for
> the way a nonce is used in cryptography, but I'd be very surprised to
> have a cryptographer tell me that a deterministic nonce didn't have
> similar issues or didn't reduce the value of the nonce significantly.

I have worked side by side on projects with bona fide cryptographers and
I can assure you that they recommended random nonces. Granted, that was
in the early 2000s, but I don't think "modern cryptography" has changed
that any more than "web scale" has made Postgres irrelevant in the
intervening years.

Related links:

https://defuse.ca/cbcmodeiv.htm
https://www.cryptofails.com/post/70059609995/crypto-noobs-1-initialization-vectors


Joe

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