On Wed, Jul 10, 2019 at 12:38:02PM -0600, Ryan Lambert wrote:
>
> what is it that gets stored in the page for
> decryption use, the nonce or the IV derived from it?
>
>
> I believe storing the IV is preferable and still secure per [1]: "The IV need
> not be secret"
>
> Beyond needing the database oid, if every decrypt function has to regenerate
> the IV from the nonce that will affect performance. I don't know how expensive
> the forward hash is but it won't be free.
Well, I think we have three options. We have 3 4-byte integers
(pg_class.oid, LSN, page-number) that could be concatenated to be the
IV, we could run those through a hash, or we could run them through the
encryption function with the secret.
--
Bruce Momjian <bruce@momjian.us> http://momjian.us
EnterpriseDB http://enterprisedb.com
+ As you are, so once was I. As I am, so you will be. +
+ Ancient Roman grave inscription +
