KEYS: PGP-based public key signature verification

Provide handlers for PGP-based public-key algorithm signature verification.
This does most of the work involved in signature verification as most of it is
public-key algorithm agnostic.  The public-key verification algorithm itself
is just the last little bit and is supplied the complete hash data to process.

This requires glue logic putting on top to make use of it - something the next
patch provides.

Signed-off-by: David Howells <dhowells@redhat.com>
3 files changed