Really ripngd should either leave groups on down interfaces, or keep

track of on which interfaces joins have occurred.  This is complicated
by the possible lack of a clear behavior spec on whether interfaces
keep their joined group lists across a down/up/down transition.  (On
NetBSD, they do.)

2004-01-03  Greg Troxel  <gdt@ahi.ir.bbn.com>

        * ripng_interface.c (ripng_multicast_join): If IPV6_JOIN_GROUP
        returns EADDRINUSE, consider the join successful.  This happens
        when an interface goes down and comes back because
        ripng_multicast_leave does not invoke the LEAVE_GROUP operation if
        the interface is down.  Solves problem of ripng stopping working
        on an interface which goes down and then comes back up (on NetBSD).

diff --git a/ripngd/ChangeLog b/ripngd/ChangeLog
index fa1351030d72b9b89d46ebd60403499ba38dee1d..f5a3078755368efb47cf999cff4730f8a236843b 100644 (file)
--- a/ripngd/ChangeLog
+++ b/ripngd/ChangeLog
@@ -1,3 +1,12 @@
+2004-01-03  Greg Troxel  <gdt@ahi.ir.bbn.com>
+
+       * ripng_interface.c (ripng_multicast_join): If IPV6_JOIN_GROUP
+       returns EADDRINUSE, consider the join successful.  This happens
+       when an interface goes down and comes back because
+       ripng_multicast_leave does not invoke the LEAVE_GROUP operation if
+       the interface is down.  Solves problem of ripng stopping working
+       on an interface which goes down and then comes back up (on NetBSD).
+
 2003-05-25 Hasso Tepper <hasso@estpak.ee>
   
   * Revert ripng_ifrmap stuff because ripd uses it now as well.

diff --git a/ripngd/ripng_interface.c b/ripngd/ripng_interface.c
index b4299eb07af9025bd4fe520189bc895347c82c35..7437f70fa5d6e0af6c080c655db8a9f04bf21240 100644 (file)
--- a/ripngd/ripng_interface.c
+++ b/ripngd/ripng_interface.c
@@ -67,6 +67,18 @@ ripng_multicast_join (struct interface *ifp)
 
     ret = setsockopt (ripng->sock, IPPROTO_IPV6, IPV6_JOIN_GROUP,
                      (char *) &mreq, sizeof (mreq));
+
+    if (ret < 0 && errno == EADDRINUSE)
+      {
+       /*
+        * Group is already joined.  This occurs due to sloppy group
+        * management, in particular declining to leave the group on
+        * an interface that has just gone down.
+        */
+       zlog_warn ("ripng join on %s EADDRINUSE (ignoring)\n", ifp->name);
+       return 0;               /* not an error */
+      }
+
     if (ret < 0)
       zlog_warn ("can't setsockopt IPV6_JOIN_GROUP: %s", strerror (errno));