1 files changed, 113 insertions, 0 deletions

diff --git a/net/xfrm/xfrm_input.c b/net/xfrm/xfrm_input.c
index 4c803f7e74e5..b980095be935 100644
--- a/net/xfrm/xfrm_input.c
+++ b/net/xfrm/xfrm_input.c
@@ -9,6 +9,8 @@
 
 #include <linux/slab.h>
 #include <linux/module.h>
+#include <linux/netdevice.h>
+#include <net/dst.h>
 #include <net/ip.h>
 #include <net/xfrm.h>
 
@@ -94,6 +96,117 @@ int xfrm_prepare_input(struct xfrm_state *x, struct sk_buff *skb)
 }
 EXPORT_SYMBOL(xfrm_prepare_input);
 
+int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
+{
+        int err;
+        __be32 seq;
+        struct xfrm_state *xfrm_vec[XFRM_MAX_DEPTH];
+        struct xfrm_state *x;
+        int xfrm_nr = 0;
+        int decaps = 0;
+        unsigned int nhoff = XFRM_SPI_SKB_CB(skb)->nhoff;
+        unsigned int daddroff = XFRM_SPI_SKB_CB(skb)->daddroff;
+
+        seq = 0;
+        if (!spi && (err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) != 0)
+                goto drop;
+
+        do {
+                if (xfrm_nr == XFRM_MAX_DEPTH)
+                        goto drop;
+
+                x = xfrm_state_lookup((xfrm_address_t *)
+                                      (skb_network_header(skb) + daddroff),
+                                      spi, nexthdr, AF_INET);
+                if (x == NULL)
+                        goto drop;
+
+                spin_lock(&x->lock);
+                if (unlikely(x->km.state != XFRM_STATE_VALID))
+                        goto drop_unlock;
+
+                if ((x->encap ? x->encap->encap_type : 0) != encap_type)
+                        goto drop_unlock;
+
+                if (x->props.replay_window && xfrm_replay_check(x, seq))
+                        goto drop_unlock;
+
+                if (xfrm_state_check_expire(x))
+                        goto drop_unlock;
+
+                nexthdr = x->type->input(x, skb);
+                if (nexthdr <= 0)
+                        goto drop_unlock;
+
+                skb_network_header(skb)[nhoff] = nexthdr;
+
+                /* only the first xfrm gets the encap type */
+                encap_type = 0;
+
+                if (x->props.replay_window)
+                        xfrm_replay_advance(x, seq);
+
+                x->curlft.bytes += skb->len;
+                x->curlft.packets++;
+
+                spin_unlock(&x->lock);
+
+                xfrm_vec[xfrm_nr++] = x;
+
+                if (x->inner_mode->input(x, skb))
+                        goto drop;
+
+                if (x->outer_mode->flags & XFRM_MODE_FLAG_TUNNEL) {
+                        decaps = 1;
+                        break;
+                }
+
+                err = xfrm_parse_spi(skb, nexthdr, &spi, &seq);
+                if (err < 0)
+                        goto drop;
+        } while (!err);
+
+        /* Allocate new secpath or COW existing one. */
+
+        if (!skb->sp || atomic_read(&skb->sp->refcnt) != 1) {
+                struct sec_path *sp;
+                sp = secpath_dup(skb->sp);
+                if (!sp)
+                        goto drop;
+                if (skb->sp)
+                        secpath_put(skb->sp);
+                skb->sp = sp;
+        }
+        if (xfrm_nr + skb->sp->len > XFRM_MAX_DEPTH)
+                goto drop;
+
+        memcpy(skb->sp->xvec + skb->sp->len, xfrm_vec,
+               xfrm_nr * sizeof(xfrm_vec[0]));
+        skb->sp->len += xfrm_nr;
+
+        nf_reset(skb);
+
+        if (decaps) {
+                dst_release(skb->dst);
+                skb->dst = NULL;
+                netif_rx(skb);
+                return 0;
+        } else {
+                return x->inner_mode->afinfo->transport_finish(skb, 0);
+        }
+
+drop_unlock:
+        spin_unlock(&x->lock);
+        xfrm_state_put(x);
+drop:
+        while (--xfrm_nr >= 0)
+                xfrm_state_put(xfrm_vec[xfrm_nr]);
+
+        kfree_skb(skb);
+        return 0;
+}
+EXPORT_SYMBOL(xfrm_input);
+
 void __init xfrm_input_init(void)
 {
         secpath_cachep = kmem_cache_create("secpath_cache",