[IPV6]: Add ip6_local_out

Most callers of the LOCAL_OUT chain will set the IP packet length
before doing so.  They also share the same output function dst_output.

This patch creates a new function called ip6_local_out which does all
of that and converts the appropriate users over to it.

Apart from removing duplicate code, it will also help in merging the
IPsec output path.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 30 insertions, 18 deletions

diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index 387030d2483c..bd121f9ae0a7 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -29,7 +29,7 @@
  */
 
 #include <linux/errno.h>
-#include <linux/types.h>
+#include <linux/kernel.h>
 #include <linux/string.h>
 #include <linux/socket.h>
 #include <linux/net.h>
@@ -70,6 +70,31 @@ static __inline__ void ipv6_select_ident(struct sk_buff *skb, struct frag_hdr *f
         spin_unlock_bh(&ip6_id_lock);
 }
 
+int __ip6_local_out(struct sk_buff *skb)
+{
+        int len;
+
+        len = skb->len - sizeof(struct ipv6hdr);
+        if (len > IPV6_MAXPLEN)
+                len = 0;
+        ipv6_hdr(skb)->payload_len = htons(len);
+
+        return nf_hook(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, skb->dst->dev,
+                       dst_output);
+}
+
+int ip6_local_out(struct sk_buff *skb)
+{
+        int err;
+
+        err = __ip6_local_out(skb);
+        if (likely(err == 1))
+                err = dst_output(skb);
+
+        return err;
+}
+EXPORT_SYMBOL_GPL(ip6_local_out);
+
 static int ip6_output_finish(struct sk_buff *skb)
 {
         struct dst_entry *dst = skb->dst;
@@ -1403,10 +1428,6 @@ int ip6_push_pending_frames(struct sock *sk)
         *(__be32*)hdr = fl->fl6_flowlabel |
                      htonl(0x60000000 | ((int)np->cork.tclass << 20));
 
-        if (skb->len <= sizeof(struct ipv6hdr) + IPV6_MAXPLEN)
-                hdr->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
-        else
-                hdr->payload_len = 0;
         hdr->hop_limit = np->cork.hop_limit;
         hdr->nexthdr = proto;
         ipv6_addr_copy(&hdr->saddr, &fl->fl6_src);
@@ -1423,7 +1444,7 @@ int ip6_push_pending_frames(struct sock *sk)
                 ICMP6_INC_STATS_BH(idev, ICMP6_MIB_OUTMSGS);
         }
 
-        err = NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, skb->dst->dev, dst_output);
+        err = ip6_local_out(skb);
         if (err) {
                 if (err > 0)
                         err = np->recverr ? net_xmit_errno(err) : 0;
diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c
index a4051afaf776..29b5321e39c3 100644
--- a/net/ipv6/ip6_tunnel.c
+++ b/net/ipv6/ip6_tunnel.c
@@ -910,15 +910,13 @@ static int ip6_tnl_xmit2(struct sk_buff *skb,
         *(__be32*)ipv6h = fl->fl6_flowlabel | htonl(0x60000000);
         dsfield = INET_ECN_encapsulate(0, dsfield);
         ipv6_change_dsfield(ipv6h, ~INET_ECN_MASK, dsfield);
-        ipv6h->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
         ipv6h->hop_limit = t->parms.hop_limit;
         ipv6h->nexthdr = proto;
         ipv6_addr_copy(&ipv6h->saddr, &fl->fl6_src);
         ipv6_addr_copy(&ipv6h->daddr, &fl->fl6_dst);
         nf_reset(skb);
         pkt_len = skb->len;
-        err = NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL,
-                      skb->dst->dev, dst_output);
+        err = ip6_local_out(skb);
 
         if (net_xmit_eval(err) == 0) {
                 stats->tx_bytes += pkt_len;
diff --git a/net/ipv6/netfilter/ip6t_REJECT.c b/net/ipv6/netfilter/ip6t_REJECT.c
index 1a7d2917545d..c1c663482837 100644
--- a/net/ipv6/netfilter/ip6t_REJECT.c
+++ b/net/ipv6/netfilter/ip6t_REJECT.c
@@ -121,7 +121,6 @@ static void send_reset(struct sk_buff *oldskb)
         ip6h->version = 6;
         ip6h->hop_limit = dst_metric(dst, RTAX_HOPLIMIT);
         ip6h->nexthdr = IPPROTO_TCP;
-        ip6h->payload_len = htons(sizeof(struct tcphdr));
         ipv6_addr_copy(&ip6h->saddr, &oip6h->daddr);
         ipv6_addr_copy(&ip6h->daddr, &oip6h->saddr);
 
@@ -159,8 +158,7 @@ static void send_reset(struct sk_buff *oldskb)
 
         nf_ct_attach(nskb, oldskb);
 
-        NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, nskb, NULL, nskb->dst->dev,
-                dst_output);
+        ip6_local_out(nskb);
 }
 
 static inline void
diff --git a/net/ipv6/xfrm6_output.c b/net/ipv6/xfrm6_output.c
index c45050cfe72b..0f0ff51f6dba 100644
--- a/net/ipv6/xfrm6_output.c
+++ b/net/ipv6/xfrm6_output.c
@@ -75,16 +75,12 @@ EXPORT_SYMBOL(xfrm6_prepare_output);
 
 static inline int xfrm6_output_one(struct sk_buff *skb)
 {
-        struct ipv6hdr *iph;
         int err;
 
         err = xfrm_output(skb);
         if (err)
                 goto error_nolock;
 
-        iph = ipv6_hdr(skb);
-        iph->payload_len = htons(skb->len - sizeof(*iph));
-
         IP6CB(skb)->flags |= IP6SKB_XFRM_TRANSFORMED;
         err = 0;
 
@@ -102,8 +98,7 @@ static int xfrm6_output_finish2(struct sk_buff *skb)
         while (likely((err = xfrm6_output_one(skb)) == 0)) {
                 nf_reset(skb);
 
-                err = nf_hook(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL,
-                              skb->dst->dev, dst_output);
+                err = __ip6_local_out(skb);
                 if (unlikely(err != 1))
                         break;