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>
diff --git a/net/ipv6/ip6_input.c b/net/ipv6/ip6_input.c
index 936f489..f171e8d 100644
--- a/net/ipv6/ip6_input.c
+++ b/net/ipv6/ip6_input.c
@@ -255,6 +255,7 @@
* 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 @@
}
if (skb2) {
- skb2->dev = skb2->dst->dev;
ip6_mr_input(skb2);
}
}
diff --git a/net/ipv6/ip6mr.c b/net/ipv6/ip6mr.c
index 3c51b2d..d19a84b 100644
--- a/net/ipv6/ip6mr.c
+++ b/net/ipv6/ip6mr.c
@@ -365,7 +365,9 @@
pim = (struct pimreghdr *)skb_transport_header(skb);
if (pim->type != ((PIM_VERSION << 4) | PIM_REGISTER) ||
(pim->flags & PIM_NULL_REGISTER) ||
- (ip_compute_csum((void *)pim, sizeof(*pim)) != 0 &&
+ (csum_ipv6_magic(&ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
+ sizeof(*pim), IPPROTO_PIM,
+ csum_partial((void *)pim, sizeof(*pim), 0)) &&
csum_fold(skb_checksum(skb, 0, skb->len, 0))))
goto drop;
@@ -392,7 +394,7 @@
skb_pull(skb, (u8 *)encap - skb->data);
skb_reset_network_header(skb);
skb->dev = reg_dev;
- skb->protocol = htons(ETH_P_IP);
+ skb->protocol = htons(ETH_P_IPV6);
skb->ip_summed = 0;
skb->pkt_type = PACKET_HOST;
dst_release(skb->dst);
@@ -481,6 +483,7 @@
{
struct mif_device *v;
struct net_device *dev;
+ struct inet6_dev *in6_dev;
if (vifi < 0 || vifi >= net->ipv6.maxvif)
return -EADDRNOTAVAIL;
@@ -513,6 +516,10 @@
dev_set_allmulti(dev, -1);
+ in6_dev = __in6_dev_get(dev);
+ if (in6_dev)
+ in6_dev->cnf.mc_forwarding--;
+
if (v->flags & MIFF_REGISTER)
unregister_netdevice(dev);
@@ -622,6 +629,7 @@
int vifi = vifc->mif6c_mifi;
struct mif_device *v = &net->ipv6.vif6_table[vifi];
struct net_device *dev;
+ struct inet6_dev *in6_dev;
int err;
/* Is vif busy ? */
@@ -662,6 +670,10 @@
return -EINVAL;
}
+ in6_dev = __in6_dev_get(dev);
+ if (in6_dev)
+ in6_dev->cnf.mc_forwarding++;
+
/*
* Fill in the VIF structures
*/
@@ -838,8 +850,6 @@
skb->dst = dst_clone(pkt->dst);
skb->ip_summed = CHECKSUM_UNNECESSARY;
-
- skb_pull(skb, sizeof(struct ipv6hdr));
}
if (net->ipv6.mroute6_sk == NULL) {
@@ -1222,8 +1232,10 @@
rtnl_lock();
write_lock_bh(&mrt_lock);
- if (likely(net->ipv6.mroute6_sk == NULL))
+ if (likely(net->ipv6.mroute6_sk == NULL)) {
net->ipv6.mroute6_sk = sk;
+ net->ipv6.devconf_all->mc_forwarding++;
+ }
else
err = -EADDRINUSE;
write_unlock_bh(&mrt_lock);
@@ -1242,6 +1254,7 @@
if (sk == net->ipv6.mroute6_sk) {
write_lock_bh(&mrt_lock);
net->ipv6.mroute6_sk = NULL;
+ net->ipv6.devconf_all->mc_forwarding--;
write_unlock_bh(&mrt_lock);
mroute_clean_tables(net);
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index c4a5982..9c57423 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -794,7 +794,7 @@
.proto = iph->nexthdr,
};
- if (rt6_need_strict(&iph->daddr))
+ if (rt6_need_strict(&iph->daddr) && skb->dev->type != ARPHRD_PIMREG)
flags |= RT6_LOOKUP_F_IFACE;
skb->dst = fib6_rule_lookup(net, &fl, flags, ip6_pol_route_input);