gpg: Print PGP-2 fingerprint instead of all zeroes.
* g10/keyid.c (fingerprint_from_pk): Allow PGP-2 fingerprints. * g10/keylist.c (print_fingerprint): Print a warning after a PGP-2 fingerprint.
Printing all zeroes for a PGP-2 (v3 key) fingerprint has the problem
that frontends (or the user) may use that fingerprint to lookup a key
and gpg will return all PGP2 keys. They may then show a different
PGP-2 key than the one actually used for a signature. This is worse
than displaying a weak fingerprint.
- GnuPG-bug-id: T2000
- Signed-off-by: Werner Koch <email@example.com>