gpg: Prepare revocation keys for use with v5 keys.

* g10/packet.h (struct revocation_key): Add field 'fprlen'.
* g10/parse-packet.c (parse_revkeys): Set fprlen and allow for v5
keys.  Also fix reading of unitialized data at place where
MAX_FINGERPRINT_LEN is used.
* g10/revoke.c (gen_desig_revoke): Allow for v5 keys and use fprlen.
Do an explicit compare to avoid reading unitialized data.
* g10/sig-check.c (check_revocation_keys): Use the fprlen.
* g10/getkey.c (merge_selfsigs_main): Do an explicit copy to avoid
reading unitialized data.
* g10/import.c (revocation_present): Use fprlen.
* g10/keyedit.c (show_key_with_all_names): Use fprlen.
(menu_addrevoker): Use fprlen.  Allow for v5 keys.
* g10/keygen.c (keygen_add_revkey): Use fprlen.
(parse_revocation_key): Allow for v5 keys.
* g10/keyid.c (keyid_from_fingerprint): Allow for v5 keys.  Print a
better error message in case of bogus fingerprints.
* g10/keylist.c (print_revokers): Use fprlen.
--

The reading of uninitialized data is harmless but we better fix it to
make valgrind happy.  More serious was that we always passed
MAX_FINGERPRINT_LEN but we will need to support 20 and 32 octet
fingerprints and MAX_FINGERPRINT_LEN would be too large for a v4.

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

1 files changed, 16 insertions, 4 deletions

diff --git a/g10/getkey.c b/g10/getkey.c
index c776a6100..039a5edb5 100644
--- a/g10/getkey.c
+++ b/g10/getkey.c
@@ -2577,10 +2577,22 @@ merge_selfsigs_main (ctrl_t ctrl, kbnode_t keyblock, int *r_revoked,
 			xrealloc (pk->revkey, sizeof (struct revocation_key) *
 				  (pk->numrevkeys + sig->numrevkeys));
 
-		      for (i = 0; i < sig->numrevkeys; i++)
-			memcpy (&pk->revkey[pk->numrevkeys++],
-				&sig->revkey[i],
-				sizeof (struct revocation_key));
+		      for (i = 0; i < sig->numrevkeys; i++, pk->numrevkeys++)
+                        {
+                          pk->revkey[pk->numrevkeys].class
+                            = sig->revkey[i].class;
+                          pk->revkey[pk->numrevkeys].algid
+                            = sig->revkey[i].algid;
+                          pk->revkey[pk->numrevkeys].fprlen
+                            = sig->revkey[i].fprlen;
+                          memcpy (pk->revkey[pk->numrevkeys].fpr,
+                                  sig->revkey[i].fpr, sig->revkey[i].fprlen);
+                          memset (pk->revkey[pk->numrevkeys].fpr
+                                  + sig->revkey[i].fprlen,
+                                  0,
+                                  sizeof (sig->revkey[i].fpr)
+                                  - sig->revkey[i].fprlen);
+                        }
 		    }
 
 		  if (sig->timestamp >= sigdate)