dirmngr: Support new gpgNtds parameter in LDAP keyserver URLs.

* dirmngr/ldap-parse-uri.c (ldap_parse_uri): Support a new gpgNtds
extension.
* dirmngr/ks-engine-ldap.c (my_ldap_connect): Do ldap_init always with
hostname - which is NULL and thus the same if not given.  Fix minor
error in error code handling.
--

Note that "gpgNtds" is per RFC-4512 case insensitive and has not yet
been officially regisetered.  Thus for correctness the OID can be
used:

  1.3.6.1.4.1.11591.2.5          LDAP URL extensions
  1.3.6.1.4.1.11591.2.5.1          gpgNtds=1 (auth. with current user)

Note that the value must be 1; all other values won't enable AD
authentication and are resevered for future use.

This has been cherry-picked from the 2.2 branch,
commit 55f46b33df08e8e0ea520ade5f73b321bc01d705

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

1 files changed, 16 insertions, 2 deletions

diff --git a/dirmngr/ldap-parse-uri.c b/dirmngr/ldap-parse-uri.c
index 41633acf0..573bcc77f 100644
--- a/dirmngr/ldap-parse-uri.c
+++ b/dirmngr/ldap-parse-uri.c
@@ -71,6 +71,7 @@ ldap_parse_uri (parsed_uri_t *purip, const char *uri)
   char *dn = NULL;
   char *bindname = NULL;
   char *password = NULL;
+  char *gpg_ntds = NULL;
 
   char **s;
 
@@ -107,6 +108,15 @@ ldap_parse_uri (parsed_uri_t *purip, const char *uri)
 	  else
 	    password = *s + 9;
 	}
+      else if (!ascii_strncasecmp (*s, "gpgNtds=", 8)
+              || !strncmp (*s, "1.3.6.1.4.1.11591.2.5.1=", 24))
+	{
+	  if (gpg_ntds)
+	    log_error ("gpgNtds given multiple times in URL '%s', ignoring.\n",
+		       uri);
+	  else
+	    gpg_ntds = *s + (**s == 'g'? 8 : 24);
+	}
       else
 	log_error ("Unhandled extension (%s) in URL '%s', ignoring.",
 		   *s, uri);
@@ -167,10 +177,14 @@ ldap_parse_uri (parsed_uri_t *purip, const char *uri)
   puri->port = lud->lud_port;
 
   /* On Windows detect whether this is ldap:// or ldaps:// to indicate
-   * that authentication via AD and the current user is requested.  */
+   * that authentication via AD and the current user is requested.
+   * This is shortform of adding "gpgNtDs=1" as extension parameter to
+   * the URL.  */
   puri->ad_current = 0;
+  if (gpg_ntds && atoi (gpg_ntds) == 1)
+    puri->ad_current = 1;
 #ifdef HAVE_W32_SYSTEM
-  if ((!puri->host || !*puri->host)
+  else if ((!puri->host || !*puri->host)
       && (!puri->path || !*puri->path)
       && (!puri->auth || !*puri->auth)
       && !password