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

On 7/10/19 3:53 PM, Alvaro Herrera wrote:
> On 2019-Jul-10, Bruce Momjian wrote:
> 
>> Good, so I think we all now agree we have to put the nonce
>> (pg_class.oid, LSN, page-number) though the cipher using the secret.

(been traveling -- just trying to get caught up on this thread)

> Actually, why do you need the page number in the nonce?  The LSN already
> distinguishes pages -- you can't have two pages with the same LSN, can
> you?  (I do think you can have multiple writes of the same page with
> different LSNs, if you change hint bits and don't write WAL about it,

Do you mean "multiple writes of the same page without..."?

> but maybe we should force CRC enabled in encrypted tables, which I think
> closes this hole?)

If we can use the LSN (perhaps with CRC) without the page number that
would seem to be a good idea.

Joe

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