A new server config option "fqdn-reply" specifies whether the server

should send out option 81 (FQDN).  Defaults to "on".  If set to "off",
the FQDN option is not sent, even if the client requested it.  This is
needed because some clients misbehave otherwise. [rt16624]

server/ddns.c

@@ -34,7 +34,7 @@
 
 #ifndef lint
 static char copyright[] =
-"$Id: ddns.c,v 1.25 2007/04/03 16:46:03 dhankins Exp $ Copyright (c) 2004-2007 Internet Systems Consortium.  All rights reserved.\n";
+"$Id: ddns.c,v 1.26 2007/04/27 22:48:00 each Exp $ Copyright (c) 2004-2007 Internet Systems Consortium.  All rights reserved.\n";
 #endif /* not lint */
 
 #include "dhcpd.h"
@@ -597,6 +597,21 @@ int ddns_updates (struct packet *packet,
 	}
 
       noerror:
+	/*
+	 * If fqdn-reply option is disabled in dhcpd.conf, then don't
+	 * send the client an FQDN option at all, even if one was requested.
+	 * (WinXP clients allegedly misbehave if the option is present,
+	 * refusing to handle PTR updates themselves).
+	 */
+	if ((oc = lookup_option (&server_universe, state->options,
+  				 SV_FQDN_REPLY)) &&
+  	    !evaluate_boolean_option_cache (&ignorep, packet, lease,
+  					    (struct client_state *)0,
+  					    packet->options,
+  					    state->options,
+  					    &lease->scope, oc, MDL)) {
+  	    	goto badfqdn;
+
 	/* If we're ignoring client updates, then we tell a sort of 'white
 	 * lie'.  We've already updated the name the server wants (per the
 	 * config written by the server admin).  Now let the client do as
@@ -605,7 +620,7 @@ int ddns_updates (struct packet *packet,
 	 * We only form an FQDN option this way if the client supplied an
 	 * FQDN option that had FQDN_SERVER_UPDATE set false.
 	 */
-	if (client_ignorep &&
+	} else if (client_ignorep &&
 	    (oc = lookup_option(&fqdn_universe, packet->options,
 				FQDN_SERVER_UPDATE)) &&
 	    !evaluate_boolean_option_cache(&ignorep, packet, lease, NULL,