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

On 2019-Jul-05, Bruce Momjian wrote:

> On Fri, Jul  5, 2019 at 05:00:42PM -0400, Bruce Momjian wrote:
> > On Fri, Jul  5, 2019 at 04:24:54PM -0400, Alvaro Herrera wrote:

> > > Oh, is that the idea?  I was kinda assuming that the data was kept
> > > as-stored in shared buffers, ie. it would be decrypted on access, not on
> > > read from disk.  The system seems very prone to leakage if you have it
> > > decrypted in shared memory.
> > 
> > Well, the overhead of decrypting on every access will make the slowdown
> > huge, and I don't know what security value that would have.  I am not
> > sure what security value TDE itself has, but I think encrypting shared
> > buffer contents has even less.
> 
> Sorry I didn't answer your question directly.  Since the shared buffers
> are in memory, if the decryption key is also unlocked in memory, there
> isn't much value to encrypting shared buffers, and the overhead would be
> huge.

Oh, I get your point now.

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
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