gpg: Implement the LDAP AKL method.

* g10/keyserver.c (keyserver_import_mbox): Add arg flags and change
callers.
(keyserver_import_ldap): Remove.  It has always returned a not
implemented error since 2.1.
* g10/getkey.c (get_pubkey_byname): Repurpose LDAP to do basically the
same as KEYSERVER.
--

The old LDAP mechanism to locate a server via SRV records has long
been gone (since 2014) due to the dropping of the keyserver helpers.
The new purpose better reflects reality and can be used in
environments where keys are provided by an in-house LDAP server.

1 files changed, 22 insertions, 6 deletions

diff --git a/g10/getkey.c b/g10/getkey.c
index 3e5d32e01..e0d99311a 100644
--- a/g10/getkey.c
+++ b/g10/getkey.c
@@ -1,7 +1,7 @@
 /* getkey.c -  Get a key from the database
  * Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006,
  *               2007, 2008, 2010  Free Software Foundation, Inc.
- * Copyright (C) 2015, 2016 g10 Code GmbH
+ * Copyright (C) 2015, 2016, 2024 g10 Code GmbH
  *
  * This file is part of GnuPG.
  *
@@ -17,6 +17,7 @@
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, see <https://www.gnu.org/licenses/>.
+ * SPDX-License-Identifier: GPL-3.0-or-later
  */
 
 #include <config.h>
@@ -1176,16 +1177,31 @@ get_pubkey_byname (ctrl_t ctrl, enum get_pubkey_modes mode,
 	      break;
 
 	    case AKL_LDAP:
-              if (is_fpr)
+	      if (!keyserver_any_configured (ctrl))
                 {
                   mechanism_string = "";
                   rc = GPG_ERR_NO_PUBKEY;
                 }
               else
                 {
-                  mechanism_string = "LDAP";
+                  mechanism_string = is_fpr? "ldap/fpr":"ldap/mbox";
                   glo_ctrl.in_auto_key_retrieve++;
-                  rc = keyserver_import_ldap (ctrl, name, &fpr, &fpr_len);
+                  if (is_fpr)
+                    rc = keyserver_import_fpr (ctrl,
+                                               fprbuf.u.fpr, fprbuf.fprlen,
+                                               opt.keyserver,
+                                               KEYSERVER_IMPORT_FLAG_LDAP);
+                  else
+                    rc = keyserver_import_mbox (ctrl, name, &fpr, &fpr_len,
+                                                opt.keyserver,
+                                                KEYSERVER_IMPORT_FLAG_LDAP);
+                  /* Map error codes because Dirmngr returns NO DATA
+                   * if the keyserver does not have the requested key.
+                   * It returns NO KEYSERVER if no LDAP keyservers are
+                   * configured.  */
+                  if (gpg_err_code (rc) == GPG_ERR_NO_DATA
+                      || gpg_err_code (rc) == GPG_ERR_NO_KEYSERVER)
+                    rc = gpg_error (GPG_ERR_NO_PUBKEY);
                   glo_ctrl.in_auto_key_retrieve--;
                 }
               break;
@@ -1227,7 +1243,7 @@ get_pubkey_byname (ctrl_t ctrl, enum get_pubkey_modes mode,
                   else
                     {
                       rc = keyserver_import_mbox (ctrl, name, &fpr, &fpr_len,
-                                                  opt.keyserver);
+                                                  opt.keyserver, 0);
                     }
 		  glo_ctrl.in_auto_key_retrieve--;
 		}
@@ -1258,7 +1274,7 @@ get_pubkey_byname (ctrl_t ctrl, enum get_pubkey_modes mode,
                 else
                   {
                     rc = keyserver_import_mbox (ctrl, name,
-                                                &fpr, &fpr_len, keyserver);
+                                                &fpr, &fpr_len, keyserver, 0);
                   }
 		glo_ctrl.in_auto_key_retrieve--;
 	      }