gpg: expand GPG groups when resolving a key
* g10/expand-group.c: New * g10/pkclist.c: Extract expand_group and expand_id into expand-group.c. * g10/keydb.h: Add prototypes of expand_id and expand_group. * g10/getkey.c: Use expand_group before resolving key references. * g10/Makefile.am: Compile expand-group.c.
When searching a key by its name, try to expand the provided name in
case it is a GPG group reference. This GPG group resolution is performed
before the individual keys are verified.
This allows key listing using a GPG group reference. In particular, this
modification fixes the encryption to group support in KDE's Kmail which
is broken since version 18.04.
- Changed new filename to use a dash instead of an underscore.
- Indendation changes.
- Signed-off-by: Werner Koch <email@example.com>