gpg: New option --force-sign-key

* g10/gpg.c (oForceSignKey,opts): New option "--force-sign-key".
(main): Set it.
* g10/options.h (opt): New flag flags.force_sign_key.
* g10/keyedit.c (sign_uids): Use new flag.
--

GnuPG-bug-id: 4584

g10/gpg.c

@@ -430,6 +430,7 @@ enum cmd_and_opt_values
     oUseOnlyOpenPGPCard,
     oIncludeKeyBlock,
     oNoIncludeKeyBlock,
+    oForceSignKey,
 
     oNoop
   };
@@ -838,6 +839,7 @@ static ARGPARSE_OPTS opts[] = {
   ARGPARSE_s_s (oWeakDigest, "weak-digest","@"),
   ARGPARSE_s_n (oUnwrap, "unwrap", "@"),
   ARGPARSE_s_n (oOnlySignTextIDs, "only-sign-text-ids", "@"),
+  ARGPARSE_s_n (oForceSignKey,    "force-sign-key", "@"),
 
   /* Aliases.  I constantly mistype these, and assume other people do
      as well. */
@@ -2674,6 +2676,9 @@ main (int argc, char **argv)
 
 	  case oAnswerYes: opt.answer_yes = 1; break;
 	  case oAnswerNo: opt.answer_no = 1; break;
+
+          case oForceSignKey: opt.flags.force_sign_key = 1; break;
+
 	  case oKeyring: append_to_strlist( &nrings, pargs.r.ret_str); break;
 	  case oPrimaryKeyring:
 	    sl = append_to_strlist (&nrings, pargs.r.ret_str);

g10/keyedit.c

@@ -751,10 +751,11 @@ sign_uids (ctrl_t ctrl, estream_t fp,
                                 _("\"%s\" was already signed by key %s\n"),
 				user, keystr_from_pk (pk));
 
-		  if (opt.expert && !quick
-		      && cpr_get_answer_is_yes ("sign_uid.dupe_okay",
-						_("Do you want to sign it "
-						  "again anyway? (y/N) ")))
+		  if (opt.flags.force_sign_key
+                      || (opt.expert && !quick
+                          && cpr_get_answer_is_yes ("sign_uid.dupe_okay",
+                                                    _("Do you want to sign it "
+                                                      "again anyway? (y/N) "))))
 		    {
 		      /* Don't delete the old sig here since this is
 		         an --expert thing. */

g10/options.h

@@ -241,6 +241,8 @@ struct
     /* Force the use of the OpenPGP card and do not allow the use of
      * another card.  */
     unsigned int use_only_openpgp_card:1;
+    /* Force signing keys even if a key signature already exists.  */
+    unsigned int force_sign_key:1;
   } flags;
 
   /* Linked list of ways to find a key if the key isn't on the local