ipv4: initialise the itag variable in __mkroute_input

[pandora-kernel.git] / net / ipv4 / ip_forward.c

diff --git a/net/ipv4/ip_forward.c b/net/ipv4/ip_forward.c
index 3b34d1c..7593f3a 100644 (file)
--- a/net/ipv4/ip_forward.c
+++ b/net/ipv4/ip_forward.c
@@ -39,6 +39,68 @@
 #include <net/route.h>
 #include <net/xfrm.h>
 
+static bool ip_may_fragment(const struct sk_buff *skb)
+{
+       return unlikely((ip_hdr(skb)->frag_off & htons(IP_DF)) == 0) ||
+               skb->local_df;
+}
+
+static bool ip_exceeds_mtu(const struct sk_buff *skb, unsigned int mtu)
+{
+       if (skb->len <= mtu)
+               return false;
+
+       if (skb_is_gso(skb) && skb_gso_network_seglen(skb) <= mtu)
+               return false;
+
+       return true;
+}
+
+static bool ip_gso_exceeds_dst_mtu(const struct sk_buff *skb)
+{
+       unsigned int mtu;
+
+       if (skb->local_df || !skb_is_gso(skb))
+               return false;
+
+       mtu = dst_mtu(skb_dst(skb));
+
+       /* if seglen > mtu, do software segmentation for IP fragmentation on
+        * output.  DF bit cannot be set since ip_forward would have sent
+        * icmp error.
+        */
+       return skb_gso_network_seglen(skb) > mtu;
+}
+
+/* called if GSO skb needs to be fragmented on forward */
+static int ip_forward_finish_gso(struct sk_buff *skb)
+{
+       struct sk_buff *segs;
+       int ret = 0;
+
+       segs = skb_gso_segment(skb, 0);
+       if (IS_ERR(segs)) {
+               kfree_skb(skb);
+               return -ENOMEM;
+       }
+
+       consume_skb(skb);
+
+       do {
+               struct sk_buff *nskb = segs->next;
+               int err;
+
+               segs->next = NULL;
+               err = dst_output(segs);
+
+               if (err && ret == 0)
+                       ret = err;
+               segs = nskb;
+       } while (segs);
+
+       return ret;
+}
+
 static int ip_forward_finish(struct sk_buff *skb)
 {
        struct ip_options * opt = &(IPCB(skb)->opt);
@@ -48,6 +110,9 @@ static int ip_forward_finish(struct sk_buff *skb)
        if (unlikely(opt->optlen))
                ip_forward_options(skb);
 
+       if (ip_gso_exceeds_dst_mtu(skb))
+               return ip_forward_finish_gso(skb);
+
        return dst_output(skb);
 }
 
@@ -84,11 +149,10 @@ int ip_forward(struct sk_buff *skb)
 
        rt = skb_rtable(skb);
 
-       if (opt->is_strictroute && ip_hdr(skb)->daddr != rt->rt_gateway)
+       if (opt->is_strictroute && opt->nexthop != rt->rt_gateway)
                goto sr_failed;
 
-       if (unlikely(skb->len > dst_mtu(&rt->dst) && !skb_is_gso(skb) &&
-                    (ip_hdr(skb)->frag_off & htons(IP_DF))) && !skb->local_df) {
+       if (!ip_may_fragment(skb) && ip_exceeds_mtu(skb, dst_mtu(&rt->dst))) {
                IP_INC_STATS(dev_net(rt->dst.dev), IPSTATS_MIB_FRAGFAILS);
                icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
                          htonl(dst_mtu(&rt->dst)));