[Patch 2of2] IPv6 routers don't join/leave the all routers group

["David Stevens" <dlstevens@xxxxxxxxxx>]

This is a patch to join the "all routers" multicast group when forwarding
is
turned on for an interface, and to leave it when forwarding is turned off.
It
requires the addrconf_sysctl_forward() patch I posted previously, as well.
Patch is relative to 2.4.9.
                                   +-DLS


--- linux-2.4.9P1/net/ipv6/addrconf.c    Tue Aug 28 15:05:54 2001
+++ linux-2.4.9NEW/net/ipv6/addrconf.c   Tue Aug 28 15:45:45 2001
@@ -298,12 +298,33 @@
     return idev;
 }

+static void dev_forward_change(struct inet6_dev *idev)
+{
+    struct net_device *dev;
+    struct in6_addr addr;
+
+    if (!idev)
+         return;
+    dev = idev->dev;
+    if (!dev || !(dev->flags & IFF_MULTICAST))
+         return;
+
+    ipv6_addr_all_routers(&addr);
+
+    if (idev->cnf.forwarding)
+         ipv6_dev_mc_inc(dev, &addr);
+    else
+         ipv6_dev_mc_dec(dev, &addr);
+}
+
 static void addrconf_forward_change(struct inet6_dev *idev)
 {
     struct net_device *dev;

-    if (idev)
+    if (idev) {
+         dev_forward_change(idev);
          return;
+    }

     read_lock(&dev_base_lock);
     for (dev=dev_base; dev; dev=dev->next) {
@@ -312,6 +333,7 @@
          if (idev)
               idev->cnf.forwarding = ipv6_devconf.forwarding;
          read_unlock(&addrconf_lock);
+         dev_forward_change(idev);
     }
     read_unlock(&dev_base_lock);
 }