[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>

4 files changed, 8 insertions, 72 deletions

diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 137b8eb666b7..94ef788a2ac6 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -166,6 +166,7 @@ static struct dst_ops ipv4_dst_ops = {
         .negative_advice =      ipv4_negative_advice,
         .link_failure =         ipv4_link_failure,
         .update_pmtu =          ip_rt_update_pmtu,
+        .local_out =            ip_local_out,
         .entry_size =           sizeof(struct rtable),
 };
 
diff --git a/net/ipv4/xfrm4_output.c b/net/ipv4/xfrm4_output.c
index 0ffc3d078489..2fb4efa3ff2c 100644
--- a/net/ipv4/xfrm4_output.c
+++ b/net/ipv4/xfrm4_output.c
@@ -59,7 +59,7 @@ int xfrm4_prepare_output(struct xfrm_state *x, struct sk_buff *skb)
                 return err;
 
         memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
-        IPCB(skb)->flags |= IPSKB_XFRM_TUNNEL_SIZE;
+        IPCB(skb)->flags |= IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED;
 
         skb->protocol = htons(ETH_P_IP);
 
@@ -67,87 +67,19 @@ int xfrm4_prepare_output(struct xfrm_state *x, struct sk_buff *skb)
 }
 EXPORT_SYMBOL(xfrm4_prepare_output);
 
-static inline int xfrm4_output_one(struct sk_buff *skb)
-{
-        int err;
-
-        err = xfrm_output(skb);
-        if (err)
-                goto error_nolock;
-
-        IPCB(skb)->flags |= IPSKB_XFRM_TRANSFORMED;
-        err = 0;
-
-out_exit:
-        return err;
-error_nolock:
-        kfree_skb(skb);
-        goto out_exit;
-}
-
-static int xfrm4_output_finish2(struct sk_buff *skb)
-{
-        int err;
-
-        while (likely((err = xfrm4_output_one(skb)) == 0)) {
-                nf_reset(skb);
-
-                err = __ip_local_out(skb);
-                if (unlikely(err != 1))
-                        break;
-
-                if (!skb->dst->xfrm)
-                        return dst_output(skb);
-
-                err = nf_hook(PF_INET, NF_IP_POST_ROUTING, skb, NULL,
-                              skb->dst->dev, xfrm4_output_finish2);
-                if (unlikely(err != 1))
-                        break;
-        }
-
-        return err;
-}
-
 static int xfrm4_output_finish(struct sk_buff *skb)
 {
-        struct sk_buff *segs;
-
 #ifdef CONFIG_NETFILTER
         if (!skb->dst->xfrm) {
                 IPCB(skb)->flags |= IPSKB_REROUTED;
                 return dst_output(skb);
         }
-#endif
 
-        if (!skb_is_gso(skb))
-                return xfrm4_output_finish2(skb);
+        IPCB(skb)->flags |= IPSKB_XFRM_TRANSFORMED;
+#endif
 
         skb->protocol = htons(ETH_P_IP);
-        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 = xfrm4_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 xfrm4_output(struct sk_buff *skb)
diff --git a/net/ipv4/xfrm4_policy.c b/net/ipv4/xfrm4_policy.c
index 1d7524375b49..b4948c170b3e 100644
--- a/net/ipv4/xfrm4_policy.c
+++ b/net/ipv4/xfrm4_policy.c
@@ -237,6 +237,7 @@ static struct dst_ops xfrm4_dst_ops = {
         .update_pmtu =          xfrm4_update_pmtu,
         .destroy =              xfrm4_dst_destroy,
         .ifdown =               xfrm4_dst_ifdown,
+        .local_out =            __ip_local_out,
         .gc_thresh =            1024,
         .entry_size =           sizeof(struct xfrm_dst),
 };
diff --git a/net/ipv4/xfrm4_state.c b/net/ipv4/xfrm4_state.c
index 85f04b7b237f..80292fbf221a 100644
--- a/net/ipv4/xfrm4_state.c
+++ b/net/ipv4/xfrm4_state.c
@@ -11,6 +11,7 @@
 #include <net/xfrm.h>
 #include <linux/pfkeyv2.h>
 #include <linux/ipsec.h>
+#include <linux/netfilter_ipv4.h>
 
 static struct xfrm_state_afinfo xfrm4_state_afinfo;
 
@@ -66,6 +67,7 @@ static struct xfrm_state_afinfo xfrm4_state_afinfo = {
         .family                 = AF_INET,
         .proto                  = IPPROTO_IPIP,
         .eth_proto              = htons(ETH_P_IP),
+        .nf_post_routing        = NF_IP_POST_ROUTING,
         .owner                  = THIS_MODULE,
         .init_flags             = xfrm4_init_flags,
         .init_tempsel           = __xfrm4_init_tempsel,