ipvs: SIP fragment handling

Use the nfct_reasm SKB if available.

Based on part of a patch from: Hans Schillstrom
I have left Hans'es comment in the patch (marked /HS)

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
[ horms@verge.net.au: Fix comment style ]
Signed-off-by: Simon Horman <horms@verge.net.au>

1 files changed, 12 insertions, 4 deletions

diff --git a/net/netfilter/ipvs/ip_vs_pe_sip.c b/net/netfilter/ipvs/ip_vs_pe_sip.c
index ee4e2e3cc086..12475ef88daf 100644
--- a/net/netfilter/ipvs/ip_vs_pe_sip.c
+++ b/net/netfilter/ipvs/ip_vs_pe_sip.c
@@ -68,6 +68,7 @@ static int get_callid(const char *dptr, unsigned int dataoff,
 static int
 ip_vs_sip_fill_param(struct ip_vs_conn_param *p, struct sk_buff *skb)
 {
+        struct sk_buff *reasm = skb_nfct_reasm(skb);
         struct ip_vs_iphdr iph;
         unsigned int dataoff, datalen, matchoff, matchlen;
         const char *dptr;
@@ -78,13 +79,20 @@ ip_vs_sip_fill_param(struct ip_vs_conn_param *p, struct sk_buff *skb)
         /* Only useful with UDP */
         if (iph.protocol != IPPROTO_UDP)
                 return -EINVAL;
+        /* todo: IPv6 fragments:
+         *       I think this only should be done for the first fragment. /HS
+         */
+        if (reasm) {
+                skb = reasm;
+                dataoff = iph.thoff_reasm + sizeof(struct udphdr);
+        } else
+                dataoff = iph.len + sizeof(struct udphdr);
 
-        /* No Data ? */
-        dataoff = iph.len + sizeof(struct udphdr);
         if (dataoff >= skb->len)
                 return -EINVAL;
-
-        if ((retc=skb_linearize(skb)) < 0)
+        /* todo: Check if this will mess-up the reasm skb !!! /HS */
+        retc = skb_linearize(skb);
+        if (retc < 0)
                 return retc;
         dptr = skb->data + dataoff;
         datalen = skb->len - dataoff;