IPv6: Fix multicast routing bugs.

This patch addresses the IPv6 multicast routing issues described
below.  It was tested with XORP 1.4/1.5 as the IPv6 PIM-SM routing
daemon against FreeBSD peers.

net/ipv6/ip6_input.c:

  - Don't try to forward link-local multicast packets.

  - Don't reset skb2->dev before calling ip6_mr_input() so packets can
    be identified as coming from the PIM register vif properly.

net/ipv6/ip6mr.c:

  - Fix incoming PIM register messages processing:

    * The IPv6 pseudo-header should be included when checksumming PIM
      messages (RFC 4601 section 4.9; RFC 3973 section 4.7.1).

    * Packets decapsulated from PIM register messages should have
      skb->protocol ETH_P_IPV6.

  - Enable/disable IPv6 multicast forwarding on the corresponding
    interface when a routing daemon adds/removes a multicast virtual
    interface.

  - Remove incorrect skb_pull() to fix userspace signaling.

  - Enable/disable global IPv6 multicast forwarding when an IPv6
    multicast routing socket is opened/closed.

net/ipv6/route.c:

  - Don't use strict routing logic for packets decapsulated from PIM
    register messages (similar to disabling rp_filter for the IPv4
    case).

Signed-off-by: Thomas Goff <thomas.goff@boeing.com>
Reviewed-by: Fred Templin <fred.l.templin@boeing.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 1 insertions, 1 deletions

diff --git a/net/ipv6/ip6_input.c b/net/ipv6/ip6_input.c
index 936f48946e20..f171e8dbac91 100644
--- a/net/ipv6/ip6_input.c
+++ b/net/ipv6/ip6_input.c
@@ -255,6 +255,7 @@ int ip6_mc_input(struct sk_buff *skb)
          *      IPv6 multicast router mode is now supported ;)
          */
         if (dev_net(skb->dev)->ipv6.devconf_all->mc_forwarding &&
+            !(ipv6_addr_type(&hdr->daddr) & IPV6_ADDR_LINKLOCAL) &&
             likely(!(IP6CB(skb)->flags & IP6SKB_FORWARDED))) {
                 /*
                  * Okay, we try to forward - split and duplicate
@@ -316,7 +317,6 @@ int ip6_mc_input(struct sk_buff *skb)
                 }
 
                 if (skb2) {
-                        skb2->dev = skb2->dst->dev;
                         ip6_mr_input(skb2);
                 }
         }