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

On Wed, Jul 10, 2019 at 03:53:55PM -0400, 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.
> 
> 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,
> but maybe we should force CRC enabled in encrypted tables, which I think
> closes this hole?)

Uh, what if a transaction modifies page 0 and page 1 of the same table
--- don't those pages have the same LSN.

-- 
  Bruce Momjian  <bruce@momjian.us>        http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

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