gpg: New command --quick-add-adsk

* g10/gpg.c (enum cmd_and_opt_values): Add aQuickAddADSK.
(opts): Add --quick-add-adsk.
(main): Call the actual function.
* g10/keyedit.c (keyedit_quick_addadsk): New.
(menu_addadsk): Add arg adskfpr and change caller.
--

GnuPG-bug-id: 6395

doc/gpg.texi

@@ -770,6 +770,15 @@ specifying a value, or using ``-'' results in a key expiring in a
 reasonable default interval.  The values ``never'', ``none'' can be
 used for no expiration date.
 
+@item --quick-add-adsk @var{fpr} @var{adskfpr}
+@opindex quick-add-adsk
+Directly add an Additional Decryption Subkey to the key identified by
+the fingerprint @var{fpr}.  @var{adskfpr} is the fingerprint of
+another key's encryption subkey.  A subkey is commonly used here
+because by default a primary key has no encryption capability.  Use
+the option @option{--with-subkey-fingerprint} with a list command to
+display the subkey fingerprints.
+
 @item --generate-key
 @opindex generate-key
 @itemx --gen-key

g10/gpg.c

@@ -130,6 +130,7 @@ enum cmd_and_opt_values
     aQuickRevSig,
     aQuickAddUid,
     aQuickAddKey,
+    aQuickAddADSK,
     aQuickRevUid,
     aQuickSetExpire,
     aQuickSetPrimaryUid,
@@ -486,6 +487,7 @@ static gpgrt_opt_t opts[] = {
   ARGPARSE_c (aQuickAddUid,  "quick-adduid", "@"),
   ARGPARSE_c (aQuickAddKey,  "quick-add-key", "@"),
   ARGPARSE_c (aQuickAddKey,  "quick-addkey", "@"),
+  ARGPARSE_c (aQuickAddADSK, "quick-add-adsk", "@"),
   ARGPARSE_c (aQuickRevUid,  "quick-revoke-uid",
               N_("quickly revoke a user-id")),
   ARGPARSE_c (aQuickRevUid,  "quick-revuid", "@"),
@@ -2691,6 +2693,7 @@ main (int argc, char **argv)
 	  case aQuickKeygen:
 	  case aQuickAddUid:
 	  case aQuickAddKey:
+	  case aQuickAddADSK:
 	  case aQuickRevUid:
 	  case aQuickSetExpire:
 	  case aQuickSetPrimaryUid:
@@ -4302,6 +4305,7 @@ main (int argc, char **argv)
       case aQuickKeygen:
       case aQuickAddUid:
       case aQuickAddKey:
+      case aQuickAddADSK:
       case aQuickRevUid:
       case aQuickSetPrimaryUid:
       case aQuickUpdatePref:
@@ -4769,6 +4773,17 @@ main (int argc, char **argv)
         }
 	break;
 
+      case aQuickAddADSK:
+        {
+          if (argc != 2)
+            wrong_args ("--quick-add-adsk FINGERPRINT ADSK-FINGERPRINT");
+          if (mopt.forbid_gen_key)
+            gen_key_forbidden ();
+          else
+            keyedit_quick_addadsk (ctrl, argv[0], argv[1]);
+        }
+	break;
+
       case aQuickRevUid:
         {
           const char *uid, *uidtorev;

g10/keyedit.c

@@ -73,7 +73,8 @@ static int menu_delsig (ctrl_t ctrl, kbnode_t pub_keyblock);
 static int menu_clean (ctrl_t ctrl, kbnode_t keyblock, int self_only);
 static void menu_delkey (KBNODE pub_keyblock);
 static int menu_addrevoker (ctrl_t ctrl, kbnode_t pub_keyblock, int sensitive);
-static int menu_addadsk (ctrl_t ctrl, kbnode_t pub_keyblock);
+static int menu_addadsk (ctrl_t ctrl, kbnode_t pub_keyblock,
+                         const char *adskfpr);
 static gpg_error_t menu_expire (ctrl_t ctrl, kbnode_t pub_keyblock,
                                 int unattended, u32 newexpiration);
 static int menu_changeusage (ctrl_t ctrl, kbnode_t keyblock);
@@ -1310,7 +1311,7 @@ static struct
   { "addrevoker", cmdADDREVOKER,  KEYEDIT_NEED_SK,
     N_("add a revocation key")},
   { "addadsk", cmdADDADSK,  KEYEDIT_NEED_SK,
-    N_("add additional decryption subkeys")},
+    N_("add an additional decryption subkey")},
   { "delsig", cmdDELSIG, 0,
     N_("delete signatures from the selected user IDs")},
   { "expire", cmdEXPIRE,  KEYEDIT_NEED_SK | KEYEDIT_NEED_SUBSK,
@@ -2016,7 +2017,7 @@ keyedit_menu (ctrl_t ctrl, const char *username, strlist_t locusr,
 	  break;
 
 	case cmdADDADSK:
-          if (menu_addadsk (ctrl, keyblock))
+          if (menu_addadsk (ctrl, keyblock, NULL))
             {
               redisplay = 1;
               modified = 1;
@@ -3247,6 +3248,69 @@ keyedit_quick_addkey (ctrl_t ctrl, const char *fpr, const char *algostr,
 }
 
 
+/* Unattended ADSK setup function.
+ *
+ * FPR is the fingerprint of our key.  ADSKFPR is the fingerprint of
+ * another subkey which we want to add as ADSK to our key.
+ */
+void
+keyedit_quick_addadsk (ctrl_t ctrl, const char *fpr, const char *adskfpr)
+{
+  gpg_error_t err;
+  kbnode_t keyblock;
+  KEYDB_HANDLE kdbhd;
+  int modified = 0;
+  PKT_public_key *pk;
+
+#ifdef HAVE_W32_SYSTEM
+  /* See keyedit_menu for why we need this.  */
+  check_trustdb_stale (ctrl);
+#endif
+
+  /* We require a fingerprint because only this uniquely identifies a
+   * key and may thus be used to select a key for unattended adsk
+   * adding. */
+  if (find_by_primary_fpr (ctrl, fpr, &keyblock, &kdbhd))
+    goto leave;
+
+  if (fix_keyblock (ctrl, &keyblock))
+    modified++;
+
+  pk = keyblock->pkt->pkt.public_key;
+  if (pk->flags.revoked)
+    {
+      if (!opt.verbose)
+        show_key_with_all_names (ctrl, es_stdout, keyblock, 0, 0, 0, 0, 0, 1);
+      log_error ("%s%s", _("Key is revoked."), "\n");
+      goto leave;
+    }
+
+  /* Locate and add the ADSK.  Note that the called function already
+   * prints error messages. */
+  if (menu_addadsk (ctrl, keyblock, adskfpr))
+    modified = 1;
+  else
+    log_inc_errorcount ();  /* (We use log_info in menu_adsk) */
+
+  es_fflush (es_stdout);
+
+  /* Store.  */
+  if (modified)
+    {
+      err = keydb_update_keyblock (ctrl, kdbhd, keyblock);
+      if (err)
+        {
+          log_error (_("update failed: %s\n"), gpg_strerror (err));
+          goto leave;
+        }
+    }
+
+ leave:
+  release_kbnode (keyblock);
+  keydb_release (kdbhd);
+}
+
+
 /* Unattended expiration setting function for the main key.  If
  * SUBKEYFPRS is not NULL and SUBKEYSFPRS[0] is neither NULL, it is
  * expected to be an array of fingerprints for subkeys to change. It
@@ -4691,11 +4755,12 @@ fail:
 
 /*
  * Ask for a new additional decryption subkey and add it to the key
- * block.  Returns true if the keybloxk was changed and false
- * otherwise.
+ * block.  Returns true if the keyblock was changed and false
+ * otherwise.  If ADSKFPR is not NULL, this fucntion has been called
+ * by quick_addadsk and gives the fingerprint of the to be added key.
  */
 static int
-menu_addadsk (ctrl_t ctrl, kbnode_t pub_keyblock)
+menu_addadsk (ctrl_t ctrl, kbnode_t pub_keyblock, const char *adskfpr)
 {
   PKT_public_key *pk;
   PKT_public_key *sub_pk;
@@ -4718,6 +4783,10 @@ menu_addadsk (ctrl_t ctrl, kbnode_t pub_keyblock)
   for (;;)
     {
       xfree (answer);
+      if (adskfpr)
+        answer = xstrdup (adskfpr);
+      else
+        {
           answer = cpr_get_utf8
             ("keyedit.addadsk",
              _("Enter the fingerprint of the additional decryption subkey: "));
@@ -4726,10 +4795,14 @@ menu_addadsk (ctrl_t ctrl, kbnode_t pub_keyblock)
               err = gpg_error (GPG_ERR_CANCELED);
               goto leave;
             }
+        }
       if (classify_user_id (answer, &desc, 1)
           || desc.mode != KEYDB_SEARCH_MODE_FPR)
         {
           log_info (_("\"%s\" is not a fingerprint\n"), answer);
+          err = gpg_error (GPG_ERR_INV_USER_ID);
+          if (adskfpr)
+            goto leave;
           continue;
         }
 
@@ -4744,8 +4817,11 @@ menu_addadsk (ctrl_t ctrl, kbnode_t pub_keyblock)
         {
           log_info (_("key \"%s\" not found: %s\n"), answer,
                     gpg_strerror (err));
-          if (!opt.batch && gpg_err_code (err) == GPG_ERR_UNUSABLE_PUBKEY)
+          if ((!opt.batch || adskfpr) && !opt.quiet
+              && gpg_err_code (err) == GPG_ERR_UNUSABLE_PUBKEY)
             log_info (_("Did you specify the fingerprint of a subkey?\n"));
+          if (adskfpr)
+            goto leave;
 	  continue;
 	}
 
@@ -4767,8 +4843,10 @@ menu_addadsk (ctrl_t ctrl, kbnode_t pub_keyblock)
           err = gpg_error (GPG_ERR_WRONG_KEY_USAGE);
           log_info (_("key \"%s\" not found: %s\n"), answer,
                     gpg_strerror (err));
-          if (!opt.batch)
+          if ((!opt.batch || adskfpr) && !opt.quiet)
             log_info (_("Did you specify the fingerprint of a subkey?\n"));
+          if (adskfpr)
+            goto leave;
 	  continue;
         }
 
@@ -4788,6 +4866,9 @@ menu_addadsk (ctrl_t ctrl, kbnode_t pub_keyblock)
       if (node2)
         {
           log_info (_("key \"%s\" is already on this keyblock\n"), answer);
+          err = gpg_error (GPG_ERR_DUP_KEY);
+          if (adskfpr)
+            goto leave;
           continue;
         }
 

g10/keyedit.h

@@ -44,6 +44,7 @@ void keyedit_quick_adduid (ctrl_t ctrl, const char *username,
                            const char *newuid);
 void keyedit_quick_addkey (ctrl_t ctrl, const char *fpr, const char *algostr,
                            const char *usagestr, const char *expirestr);
+void keyedit_quick_addadsk (ctrl_t ctrl, const char *fpr, const char *adskfpr);
 void keyedit_quick_revuid (ctrl_t ctrl, const char *username,
                            const char *uidtorev);
 void keyedit_quick_sign (ctrl_t ctrl, const char *fpr,