gpg: Add experimental support for an issuer fpr.

* common/openpgpdefs.h (SIGSUBPKT_ISSUER_FPR): New.
* g10/build-packet.c (build_sig_subpkt_from_sig): Add arg PKSK and
insert the issuer fpr if needed.
* g10/sign.c (write_signature_packets): Pass signing key.
(make_keysig_packet): Ditto.
(update_keysig_packet): Ditto.
* g10/parse-packet.c (dump_sig_subpkt): Print issuer fpr.
(parse_one_sig_subpkt): Detect issuer fpr.
(can_handle_critical): Add issuer fpr.
* g10/mainproc.c (check_sig_and_print): Try to get key via fingerprint.
* g10/gpgv.c (keyserver_import_fprint): New stub.
* g10/test-stubs.c (keyserver_import_fprint): New stub.
--

This support is enabled with the --rfc4880bis option and intended to
test to recently proposed issuer fpr.

Signed-off-by: Werner Koch <wk@gnupg.org>

1 files changed, 11 insertions, 0 deletions

diff --git a/g10/test-stubs.c b/g10/test-stubs.c
index 42c91f869..f4d952665 100644
--- a/g10/test-stubs.c
+++ b/g10/test-stubs.c
@@ -177,6 +177,17 @@ keyserver_import_keyid (u32 *keyid, void *dummy)
 }
 
 int
+keyserver_import_fprint (ctrl_t ctrl, const byte *fprint,size_t fprint_len,
+			 struct keyserver_spec *keyserver)
+{
+  (void)ctrl;
+  (void)fprint;
+  (void)fprint_len;
+  (void)keyserver;
+  return -1;
+}
+
+int
 keyserver_import_cert (const char *name)
 {
   (void)name;