Re: Transparent column encryption

> On Jan 25, 2023, at 10:44 AM, Peter Eisentraut <peter(dot)eisentraut(at)enterprisedb(dot)com> wrote:
>
> Here is a new patch. Changes since v14:
>
> - Fixed some typos (review by Justin Pryzby)
> - Fixed backward compat. psql and pg_dump (review by Justin Pryzby)
> - Doc additions (review by Jacob Champion)
> - Validate column_encryption option in libpq (review by Jacob Champion)
> - Handle column encryption in inheritance
> - Change CEKs and CMKs to live inside schemas<v15-0001-Transparent-column-encryption.patch>

Thanks Peter. Here are some observations about the documentation in patch version 15.

In acronyms.sgml, the CEK and CMK entries should link to documentation, perhaps linkend="glossary-column-encryption-key" and linkend="glossary-column-master-key". These glossary entries should in turn link to linkend="ddl-column-encryption".

In ddl.sgml, the sentence "forcing encryption of certain parameters in the client library (see its documentation)" should link to linkend="libpq-connect-column-encryption".

Did you intend the use of "transparent data encryption" (rather than "transparent column encryption") in datatype.sgml? If so, what's the difference?

Is this feature intended to be available from ecpg? If so, can we maybe include an example in 36.3.4. Prepared Statements showing how to pass the encrypted values securely. If not, can we include verbiage about that limitation, so folks don't waste time trying to figure out how to do it?

The documentation for pg_dump (and pg_dumpall) now includes a --decrypt-encrypted-columns option, which I suppose requires cmklookup to first be configured, and for PGCMKLOOKUP to be exported. There isn't anything in the pg_dump docs about this, though, so maybe a link to section 5.5.3 with a warning about not running pg_dump this way on the database server itself?

How does a psql user mark a parameter as having forced encryption? A libpq user can specify this in the paramFormats array, but I don't see any syntax for doing this from psql. None of the perl tap tests you've included appear to do this (except indirectly when calling test_client); grep'ing for the libpq error message "parameter with forced encryption is not to be encrypted" in the tests has no matches. Is it just not possible? I thought you'd mentioned some syntax for this when we spoke in person, but I don't see it now.

—
Mark Dilger
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