gpg: New options import-drop-uids and export-drop-uids.

* g10/options.h (IMPORT_DROP_UIDS): New.
(EXPORT_DROP_UIDS): New.
* g10/import.c (parse_import_options): Add option "import-drop-uids".
(import_one): Don't bail out with that options and no uids found.
Also remove all uids.
(remove_all_uids): New.
* g10/export.c (parse_export_options): Add option "export-drop-uids".
(do_export_one_keyblock): Implement option.
--

These options are required for experiments with changes to the
keyserver infrastructure.

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

doc/gpg.texi

@@ -2342,6 +2342,11 @@ opposite meaning. The options are:
   on the keyring. This option is the same as running the @option{--edit-key}
   command "clean" after import. Defaults to no.
 
+  @item import-drop-uids
+  Do not import any user ids or their binding signatures.  This option
+  can be used to update only the subkeys or other non-user id related
+  information.
+
   @item repair-keys.  After import, fix various problems with the
   keys.  For example, this reorders signatures, and strips duplicate
   signatures.  Defaults to yes.
@@ -2506,6 +2511,11 @@ opposite meaning.  The options are:
   running the @option{--edit-key} command "minimize" before export except
   that the local copy of the key is not modified. Defaults to no.
 
+  @item export-drop-uids
+  Do no export any user id or attribute packets or their associates
+  signatures.  Note that due to missing user ids the resulting output is
+  not strictly RFC-4880 compliant.
+
   @item export-pka
   Instead of outputting the key material output PKA records suitable
   to put into DNS zone files.  An ORIGIN line is printed before each

g10/export.c

@@ -97,7 +97,7 @@ cleanup_export_globals (void)
 }
 
 
-/* Option parser for export options.  See parse_options fro
+/* Option parser for export options.  See parse_options for
    details.  */
 int
 parse_export_options(char *str,unsigned int *options,int noisy)
@@ -114,6 +114,8 @@ parse_export_options(char *str,unsigned int *options,int noisy)
        N_("remove unusable parts from key during export")},
       {"export-minimal",EXPORT_MINIMAL|EXPORT_CLEAN,NULL,
        N_("remove as much as possible from key during export")},
+      {"export-drop-uids", EXPORT_DROP_UIDS, NULL,
+       N_("Do not export user id or attribute packets")},
 
       {"export-pka", EXPORT_PKA_FORMAT, NULL, NULL },
       {"export-dane", EXPORT_DANE_FORMAT, NULL, NULL },
@@ -136,14 +138,20 @@ parse_export_options(char *str,unsigned int *options,int noisy)
   int rc;
 
   rc = parse_options (str, options, export_opts, noisy);
-  if (rc && (*options & EXPORT_BACKUP))
+  if (!rc)
+    return 0;
+
+  /* Alter other options we want or don't want for restore.  */
+  if ((*options & EXPORT_BACKUP))
     {
-      /* Alter other options we want or don't want for restore.  */
       *options |= (EXPORT_LOCAL_SIGS | EXPORT_ATTRIBUTES
                    | EXPORT_SENSITIVE_REVKEYS);
       *options &= ~(EXPORT_CLEAN | EXPORT_MINIMAL
                     | EXPORT_PKA_FORMAT | EXPORT_DANE_FORMAT);
     }
+  /* Dropping uids also means to drop attributes.  */
+  if ((*options & EXPORT_DROP_UIDS))
+    *options &= ~(EXPORT_ATTRIBUTES);
   return rc;
 }
 
@@ -1575,7 +1583,7 @@ do_export_one_keyblock (ctrl_t ctrl, kbnode_t keyblock, u32 *keyid,
       if (node->pkt->pkttype == PKT_COMMENT)
         continue;
 
-      /* Skip ring trust packets - they should not ne here anyway.  */
+      /* Skip ring trust packets - they should not be here anyway.  */
       if (node->pkt->pkttype == PKT_RING_TRUST)
         continue;
 
@@ -1650,6 +1658,19 @@ do_export_one_keyblock (ctrl_t ctrl, kbnode_t keyblock, u32 *keyid,
             }
         }
 
+      /* Don't export user ids (and attributes)?  This is not RFC-4880
+       * compliant but we allow it anyway.  */
+      if ((options & EXPORT_DROP_UIDS)
+          && node->pkt->pkttype == PKT_USER_ID)
+        {
+          /* Skip until we get to something that is not a user id (or
+           * attrib) or a signature on it.  */
+          while (kbctx->next && kbctx->next->pkt->pkttype == PKT_SIGNATURE)
+            kbctx = kbctx->next;
+
+          continue;
+        }
+
       /* Don't export attribs? */
       if (!(options & EXPORT_ATTRIBUTES)
           && node->pkt->pkttype == PKT_USER_ID

g10/import.c

@@ -121,6 +121,7 @@ static int chk_self_sigs (ctrl_t ctrl, kbnode_t keyblock, u32 *keyid,
 static int delete_inv_parts (ctrl_t ctrl, kbnode_t keyblock,
                              u32 *keyid, unsigned int options);
 static int any_uid_left (kbnode_t keyblock);
+static int remove_all_uids (kbnode_t *keyblock);
 static int merge_blocks (ctrl_t ctrl, unsigned int options,
                          kbnode_t keyblock_orig,
 			 kbnode_t keyblock, u32 *keyid,
@@ -181,6 +182,9 @@ parse_import_options(char *str,unsigned int *options,int noisy)
       {"import-minimal",IMPORT_MINIMAL|IMPORT_CLEAN,NULL,
        N_("remove as much as possible from key after import")},
 
+      {"import-drop-uids", IMPORT_DROP_UIDS, NULL,
+       N_("Do not import user id or attribute packets")},
+
       {"import-export", IMPORT_EXPORT, NULL,
        N_("run import filters and export key immediately")},
 
@@ -1728,7 +1732,9 @@ import_one (ctrl_t ctrl,
     }
 
 
-  if (!uidnode )
+  /* Unless import-drop-uids has been requested we don't allow import
+   * of a key without UIDs.  */
+  if (!uidnode && !(options & IMPORT_DROP_UIDS))
     {
       if (!silent)
         log_error( _("key %s: no user ID\n"), keystr_from_pk(pk));
@@ -1755,7 +1761,11 @@ import_one (ctrl_t ctrl,
         return 0;
     }
 
-  collapse_uids(&keyblock);
+  /* Remove or collapse the user ids.  */
+  if ((options & IMPORT_DROP_UIDS))
+    remove_all_uids (&keyblock);
+  else
+    collapse_uids (&keyblock);
 
   /* Clean the key that we're about to import, to cut down on things
      that we have to clean later.  This has no practical impact on the
@@ -1802,7 +1812,10 @@ import_one (ctrl_t ctrl,
 	  }
     }
 
-  if (!delete_inv_parts (ctrl, keyblock, keyid, options ) )
+  /* Delete invalid parts and without the drop otions bail out if
+   * there are no user ids.  */
+  if (!delete_inv_parts (ctrl, keyblock, keyid, options)
+      && !(options & IMPORT_DROP_UIDS) )
     {
       if (!silent)
         {
@@ -3417,14 +3430,51 @@ any_uid_left (kbnode_t keyblock)
 
 
 
-/****************
+/* Delete all user ids from KEYBLOCK.
+ * Returns: True if the keyblock has changed.  */
+static int
+remove_all_uids (kbnode_t *keyblock)
+{
+  kbnode_t node;
+  int any = 0;
+
+  for (node = *keyblock; node; node = node->next)
+    {
+      if (is_deleted_kbnode (node))
+	continue;
+
+      if (node->pkt->pkttype != PKT_USER_ID)
+	continue;
+
+      /* We are at the first user id.  Delete everything up to the
+       * first subkey.  */
+      for (; node; node = node->next)
+	{
+	  if (is_deleted_kbnode (node))
+	    continue;
+
+	  if (node->pkt->pkttype == PKT_PUBLIC_SUBKEY
+              || node->pkt->pkttype == PKT_SECRET_SUBKEY)
+	    break;
+          delete_kbnode (node);
+          any = 1;
+	}
+      break;  /* All done.  */
+    }
+
+  commit_kbnode (keyblock);
+  return any;
+}
+
+
+/*
  * It may happen that the imported keyblock has duplicated user IDs.
  * We check this here and collapse those user IDs together with their
  * sigs into one.
  * Returns: True if the keyblock has changed.
  */
 int
-collapse_uids( kbnode_t *keyblock )
+collapse_uids (kbnode_t *keyblock)
 {
   kbnode_t uid1;
   int any=0;

g10/misc.c

@@ -1521,6 +1521,8 @@ optlen(const char *s)
     return strlen(s);
 }
 
+
+/* Note: This function returns true on success.  */
 int
 parse_options(char *str,unsigned int *options,
 	      struct parse_options *opts,int noisy)

g10/options.h

@@ -360,6 +360,7 @@ EXTERN_UNLESS_MAIN_MODULE int memory_stat_debug_mode;
 #define IMPORT_RESTORE                   (1<<10)
 #define IMPORT_REPAIR_KEYS               (1<<11)
 #define IMPORT_DRY_RUN                   (1<<12)
+#define IMPORT_DROP_UIDS                 (1<<13)
 
 #define EXPORT_LOCAL_SIGS                (1<<0)
 #define EXPORT_ATTRIBUTES                (1<<1)
@@ -370,6 +371,7 @@ EXTERN_UNLESS_MAIN_MODULE int memory_stat_debug_mode;
 #define EXPORT_PKA_FORMAT                (1<<6)
 #define EXPORT_DANE_FORMAT               (1<<7)
 #define EXPORT_BACKUP                    (1<<10)
+#define EXPORT_DROP_UIDS                 (1<<13)
 
 #define LIST_SHOW_PHOTOS                 (1<<0)
 #define LIST_SHOW_POLICY_URLS            (1<<1)