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

On Thu, Jul 25, 2019 at 01:18:44PM -0400, Bruce Momjian wrote:
> > Key Management
> > ==============
> > We will use 3-tier key architecture as Joe proposed.
> > 
> >   1. A master key encryption key (KEK): this is the ley supplied by the
> >      database admin using something akin to ssl_passphrase_command
> > 
> >   2. A master data encryption key (MDEK): this is a generated key using a
> >      cryptographically secure pseudo-random number generator. It is
> >      encrypted using the KEK, probably with Key Wrap (KW):
> >      or maybe better Key Wrap with Padding (KWP):
> > 
> >   3a. Per table data encryption keys (TDEK): use MDEK and HKDF to generate
> >       table specific keys.
> 
> What is the value of a per-table encryption key?  How is HKDF derived?
> Are we still unclear if the 68GB limit is per encryption key or per
> encryption key/IV combination?

Oh, I see you got this from Joe Conway's email.  Let me reply to that
now.  (I am obviously having problems keeping this thread in my head as
well.)

-- 
  Bruce Momjian          http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

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