On Tue, Jul 09, 2019 at 05:31:49PM -0400, Alvaro Herrera wrote:
On 2019-Jul-09, Tomas Vondra wrote:
On Tue, Jul 09, 2019 at 05:06:45PM -0400, Alvaro Herrera wrote:
> On 2019-Jul-09, Joe Conway wrote:
>
> > > Ot you could just encrypt them with a different key, and you would not
> > > need to make database OID part of the nonce.
> >
> > Yeah that was pretty much exactly what I was trying to say above ;-)
>
> So you need to decrypt each file and encrypt again when doing CREATE
> DATABASE?
The question is whether we actually need to do that?
I mean if the new database is supposed to be encrypted with key B, you
can't just copy the files from the other database, since they are
encrypted with key A, right? Even if you consider that both copies of
each table have the same OID and each block has the same nonce.
Sure, if the databases are supposed to be encrypted with different keys,
then we may need to re-encrypt the files. I don't see a way around that,
but maybe we could use the scheme with master key somehow.
Do we change OIDs of relations when creating the database? If not, we
don't need to re-encrypt because having copies of the same block
encrypted with the same nonce is not an issue (just like copying
encrypted files is not an issue).
Are you thinking that the files can be decrypted by the two keys
somehow?
No, I was kinda assuming the database will start with the same key, but
that might have been a silly idea.
regards
--
Tomas Vondra http://www.2ndQuadrant.com
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