[IPSEC]: Merge most of the output path

As part of the work on asynchrnous cryptographic operations, we need
to be able to resume from the spot where they occur.  As such, it
helps if we isolate them to one spot.

This patch moves most of the remaining family-specific processing into
the common output code.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index ac70e2d..4ef2cfa 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -113,6 +113,7 @@
 	.negative_advice	=	ip6_negative_advice,
 	.link_failure		=	ip6_link_failure,
 	.update_pmtu		=	ip6_rt_update_pmtu,
+	.local_out		=	ip6_local_out,
 	.entry_size		=	sizeof(struct rt6_info),
 };
 
diff --git a/net/ipv6/xfrm6_output.c b/net/ipv6/xfrm6_output.c
index 0f0ff51..a0a9249 100644
--- a/net/ipv6/xfrm6_output.c
+++ b/net/ipv6/xfrm6_output.c
@@ -66,6 +66,9 @@
 		return err;
 
 	memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
+#ifdef CONFIG_NETFILTER
+	IP6CB(skb)->flags |= IP6SKB_XFRM_TRANSFORMED;
+#endif
 
 	skb->protocol = htons(ETH_P_IPV6);
 
@@ -73,80 +76,14 @@
 }
 EXPORT_SYMBOL(xfrm6_prepare_output);
 
-static inline int xfrm6_output_one(struct sk_buff *skb)
-{
-	int err;
-
-	err = xfrm_output(skb);
-	if (err)
-		goto error_nolock;
-
-	IP6CB(skb)->flags |= IP6SKB_XFRM_TRANSFORMED;
-	err = 0;
-
-out_exit:
-	return err;
-error_nolock:
-	kfree_skb(skb);
-	goto out_exit;
-}
-
-static int xfrm6_output_finish2(struct sk_buff *skb)
-{
-	int err;
-
-	while (likely((err = xfrm6_output_one(skb)) == 0)) {
-		nf_reset(skb);
-
-		err = __ip6_local_out(skb);
-		if (unlikely(err != 1))
-			break;
-
-		if (!skb->dst->xfrm)
-			return dst_output(skb);
-
-		err = nf_hook(PF_INET6, NF_IP6_POST_ROUTING, skb, NULL,
-			      skb->dst->dev, xfrm6_output_finish2);
-		if (unlikely(err != 1))
-			break;
-	}
-
-	return err;
-}
-
 static int xfrm6_output_finish(struct sk_buff *skb)
 {
-	struct sk_buff *segs;
-
-	if (!skb_is_gso(skb))
-		return xfrm6_output_finish2(skb);
+#ifdef CONFIG_NETFILTER
+	IP6CB(skb)->flags |= IP6SKB_XFRM_TRANSFORMED;
+#endif
 
 	skb->protocol = htons(ETH_P_IPV6);
-	segs = skb_gso_segment(skb, 0);
-	kfree_skb(skb);
-	if (unlikely(IS_ERR(segs)))
-		return PTR_ERR(segs);
-
-	do {
-		struct sk_buff *nskb = segs->next;
-		int err;
-
-		segs->next = NULL;
-		err = xfrm6_output_finish2(segs);
-
-		if (unlikely(err)) {
-			while ((segs = nskb)) {
-				nskb = segs->next;
-				segs->next = NULL;
-				kfree_skb(segs);
-			}
-			return err;
-		}
-
-		segs = nskb;
-	} while (segs);
-
-	return 0;
+	return xfrm_output(skb);
 }
 
 int xfrm6_output(struct sk_buff *skb)
diff --git a/net/ipv6/xfrm6_policy.c b/net/ipv6/xfrm6_policy.c
index 63932c5..a31dd53 100644
--- a/net/ipv6/xfrm6_policy.c
+++ b/net/ipv6/xfrm6_policy.c
@@ -252,6 +252,7 @@
 	.update_pmtu =		xfrm6_update_pmtu,
 	.destroy =		xfrm6_dst_destroy,
 	.ifdown =		xfrm6_dst_ifdown,
+	.local_out =		__ip6_local_out,
 	.gc_thresh =		1024,
 	.entry_size =		sizeof(struct xfrm_dst),
 };
diff --git a/net/ipv6/xfrm6_state.c b/net/ipv6/xfrm6_state.c
index 90fef0a..bb09e85 100644
--- a/net/ipv6/xfrm6_state.c
+++ b/net/ipv6/xfrm6_state.c
@@ -14,6 +14,7 @@
 #include <net/xfrm.h>
 #include <linux/pfkeyv2.h>
 #include <linux/ipsec.h>
+#include <linux/netfilter_ipv6.h>
 #include <net/dsfield.h>
 #include <net/ipv6.h>
 #include <net/addrconf.h>
@@ -189,6 +190,7 @@
 	.family			= AF_INET6,
 	.proto			= IPPROTO_IPV6,
 	.eth_proto		= htons(ETH_P_IPV6),
+	.nf_post_routing	= NF_IP6_POST_ROUTING,
 	.owner			= THIS_MODULE,
 	.init_tempsel		= __xfrm6_init_tempsel,
 	.tmpl_sort		= __xfrm6_tmpl_sort,