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

On Sat, Aug 17, 2019 at 08:16:06AM +0200, Antonin Houska wrote:
> Bruce Momjian <bruce(at)momjian(dot)us> wrote:
>
> > On Thu, Aug 15, 2019 at 09:01:05PM -0400, Stephen Frost wrote:
> > > * Bruce Momjian (bruce(at)momjian(dot)us) wrote:
> > > > Why would it not be simpler to have the cluster_passphrase_command run
> > > > whatever command-line program it wants? If you don't want to use a
> > > > shell command, create an executable and call that.
> > >
> > > Having direct integration with a KMS would certainly be valuable, and I
> > > don't see a reason to deny users that option if someone would like to
> > > spend time implementing it- in addition to a simpler mechanism such as a
> > > passphrase command, which I believe is what was being suggested here.
> >
> > OK, I am just trying to see why we would not use the
> > cluster_passphrase_command-like interface to do that.
>
> One problem that occurs to me is that PG may need to send some sort of
> credentials to the KMS. If it runs a separate process to execute the command,
> it needs to pass those credentials to it. Whether it does so via parameters or
> environment variables, both can be seen by other users.

Yes, that would be a good reason to use an external library, if we can't
figure out a clean API like opening a pipe into the command-line tool
and piping in the secret.

--
Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://enterprisedb.com

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