Re: netfilter6: ICMPv6 type 143 doesn't match

[Patrick McHardy <kaber@xxxxxxxxx>]

David S. Miller wrote:
> On Fri, 06 May 2005 00:32:31 +0200
> Patrick McHardy <kaber@xxxxxxxxx> wrote:
> 
>>Is there a reason why these packets never hit the POST_ROUTING hook?
> 
> I think it is an oversight rather than intentional.
> 
> The NDISC lookup stuff wrt. routing went back and forth
> implementation wise.  We used to use a seperate routing
> table for NDISC entries, but that caused all kinds of
> problems wrt. IPSEC (which the seperate routing table
> was ironically meant to fix) so that got undone and now
> NDISC routes and normal routes exist in one table.
> 
> So I think this oversight is just fallout from all of
> those changes.

Thanks, I've added a call to NF_HOOK(NF_IP6_POST_ROUTING) to the patch.

Index: net/ipv6/mcast.c
===================================================================
--- 2cfdb1827d9c176f4df42619c693e7b990a61963/net/ipv6/mcast.c  (mode:100644 
sha1:393b6e6f50a9626e2894c9a5abd8dafd903e5eba)
+++ uncommitted/net/ipv6/mcast.c  (mode:100644)
@@ -1280,15 +1280,6 @@
                return NULL;
 
        skb_reserve(skb, LL_RESERVED_SPACE(dev));
-       if (dev->hard_header) {
-               unsigned char ha[MAX_ADDR_LEN];
-
-               ndisc_mc_map(&mld2_all_mcr, ha, dev, 1);
-               if (dev->hard_header(skb, dev, ETH_P_IPV6,ha,NULL,size) < 0) {
-                       kfree_skb(skb);
-                       return NULL;
-               }
-       }
 
        if (ipv6_get_lladdr(dev, &addr_buf)) {
                /* <draft-ietf-magma-mld-source-05.txt>:
@@ -1312,6 +1303,31 @@
        return skb;
 }
 
+static inline int mld_dev_queue_xmit2(struct sk_buff *skb)
+{
+       struct net_device *dev = skb->dev;
+
+       if (dev->hard_header) {
+               unsigned char ha[MAX_ADDR_LEN];
+               int err;
+
+               ndisc_mc_map(&skb->nh.ipv6h->daddr, ha, dev, 1);
+               err = dev->hard_header(skb, dev, ETH_P_IPV6, ha, NULL, 
skb->len);
+               if (err < 0) {
+                       IP6_INC_STATS(IPSTATS_MIB_OUTDISCARDS);
+                       kfree_skb(skb);
+                       return err;
+               }
+       }
+       return dev_queue_xmit(skb);
+}
+
+static inline int mld_dev_queue_xmit(struct sk_buff *skb)
+{
+       return NF_HOOK(PF_INET6, NF_IP6_POST_ROUTING, skb, NULL, skb->dev,
+                      mld_dev_queue_xmit2);
+}
+
 static void mld_sendpack(struct sk_buff *skb)
 {
        struct ipv6hdr *pip6 = skb->nh.ipv6h;
@@ -1329,7 +1345,7 @@
        pmr->csum = csum_ipv6_magic(&pip6->saddr, &pip6->daddr, mldlen,
                IPPROTO_ICMPV6, csum_partial(skb->h.raw, mldlen, 0));
        err = NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, skb->dev,
-               dev_queue_xmit);
+               mld_dev_queue_xmit);
        if (!err) {
                ICMP6_INC_STATS(idev,ICMP6_MIB_OUTMSGS);
                IP6_INC_STATS(IPSTATS_MIB_OUTMCASTPKTS);
@@ -1635,12 +1651,6 @@
        }
 
        skb_reserve(skb, LL_RESERVED_SPACE(dev));
-       if (dev->hard_header) {
-               unsigned char ha[MAX_ADDR_LEN];
-               ndisc_mc_map(snd_addr, ha, dev, 1);
-               if (dev->hard_header(skb, dev, ETH_P_IPV6, ha, NULL, full_len) 
< 0)
-                       goto out;
-       }
 
        if (ipv6_get_lladdr(dev, &addr_buf)) {
                /* <draft-ietf-magma-mld-source-05.txt>:
@@ -1668,7 +1678,7 @@
        idev = in6_dev_get(skb->dev);
 
        err = NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, skb->dev,
-               dev_queue_xmit);
+               mld_dev_queue_xmit);
        if (!err) {
                if (type == ICMPV6_MGM_REDUCTION)
                        ICMP6_INC_STATS(idev, ICMP6_MIB_OUTGROUPMEMBREDUCTIONS);
@@ -1682,10 +1692,6 @@
        if (likely(idev != NULL))
                in6_dev_put(idev);
        return;
-
-out:
-       IP6_INC_STATS(IPSTATS_MIB_OUTDISCARDS);
-       kfree_skb(skb);
 }
 
 static int ip6_mc_del1_src(struct ifmcaddr6 *pmc, int sfmode,