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

Bruce Momjian <bruce@momjian.us>

From: Bruce Momjian <bruce@momjian.us>
To: Tomas Vondra <tomas.vondra@2ndquadrant.com>
Cc: Stephen Frost <sfrost@snowman.net>, Alvaro Herrera <alvherre@2ndquadrant.com>, Ryan Lambert <ryan@rustprooflabs.com>, Joe Conway <mail@joeconway.com>, Antonin Houska <ah@cybertec.at>, Masahiko Sawada <sawada.mshk@gmail.com>, Robert Haas <robertmhaas@gmail.com>, 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: 2019-07-11T00:07:49Z
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 Thu, Jul 11, 2019 at 12:18:47AM +0200, Tomas Vondra wrote:
> On Wed, Jul 10, 2019 at 06:04:30PM -0400, Stephen Frost wrote:
> > Greetings,
> > 
> > * Tomas Vondra (tomas.vondra@2ndquadrant.com) wrote:
> > > On Wed, Jul 10, 2019 at 04:11:21PM -0400, Alvaro Herrera wrote:
> > > >On 2019-Jul-10, Bruce Momjian wrote:
> > > >
> > > >>Uh, what if a transaction modifies page 0 and page 1 of the same table
> > > >>--- don't those pages have the same LSN.
> > > >
> > > >No, because WAL being a physical change log, each page gets its own
> > > >WAL record with its own LSN.
> > > >
> > > 
> > > What if you have wal_log_hints=off? AFAIK that won't change the page LSN.
> > 
> > Alvaro suggested elsewhere that we require checksums for these, which
> > would also force wal_log_hints to be on, and therefore the LSN would
> > change.
> > 
> 
> Oh, I see - yes, that would solve the hint bits issue. Not sure we want
> to combine the features like this, though, as it increases the costs of
> TDE. But maybe it's the best solution.

Uh, why can't we just force log_hint_bits for encrypted tables?  Why
would we need to use checksums as well?

Why is page-number not needed in the nonce?  Because it is duplicative
of the LSN?  Can we use just LSN?  Do we need pg_class.oid too?

-- 
  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 +