extern int xfrm_prepare_input(struct xfrm_state *x, struct sk_buff *skb);
 extern int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi,
                      int encap_type);
+extern int xfrm_input_resume(struct sk_buff *skb, int nexthdr);
 extern int xfrm_output_resume(struct sk_buff *skb, int err);
 extern int xfrm_output(struct sk_buff *skb);
 extern int xfrm4_extract_header(struct sk_buff *skb);
 
        int err;
        __be32 seq;
        struct xfrm_state *x;
+       xfrm_address_t *daddr;
        int decaps = 0;
-       unsigned int daddroff = XFRM_SPI_SKB_CB(skb)->daddroff;
+       int async = 0;
+
+       /* A negative encap_type indicates async resumption. */
+       if (encap_type < 0) {
+               async = 1;
+               x = skb->sp->xvec[skb->sp->len - 1];
+               seq = XFRM_SKB_CB(skb)->seq;
+               goto resume;
+       }
 
        /* Allocate new secpath or COW existing one. */
        if (!skb->sp || atomic_read(&skb->sp->refcnt) != 1) {
                skb->sp = sp;
        }
 
+       daddr = (xfrm_address_t *)(skb_network_header(skb) +
+                                  XFRM_SPI_SKB_CB(skb)->daddroff);
+
        seq = 0;
        if (!spi && (err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) != 0)
                goto drop;
                if (skb->sp->len == XFRM_MAX_DEPTH)
                        goto drop;
 
-               x = xfrm_state_lookup((xfrm_address_t *)
-                                     (skb_network_header(skb) + daddroff),
-                                     spi, nexthdr, AF_INET);
+               x = xfrm_state_lookup(daddr, spi, nexthdr, AF_INET);
                if (x == NULL)
                        goto drop;
 
 
                spin_unlock(&x->lock);
 
+               XFRM_SKB_CB(skb)->seq = seq;
+
                nexthdr = x->type->input(x, skb);
 
+               if (nexthdr == -EINPROGRESS)
+                       return 0;
+
+resume:
                spin_lock(&x->lock);
                if (nexthdr <= 0) {
                        if (nexthdr == -EBADMSG)
                        break;
                }
 
+               /*
+                * We need the inner address.  However, we only get here for
+                * transport mode so the outer address is identical.
+                */
+               daddr = &x->id.daddr;
+
                err = xfrm_parse_spi(skb, nexthdr, &spi, &seq);
                if (err < 0)
                        goto drop;
                netif_rx(skb);
                return 0;
        } else {
-               return x->inner_mode->afinfo->transport_finish(skb, 0);
+               return x->inner_mode->afinfo->transport_finish(skb, async);
        }
 
 drop_unlock:
 }
 EXPORT_SYMBOL(xfrm_input);
 
+int xfrm_input_resume(struct sk_buff *skb, int nexthdr)
+{
+       return xfrm_input(skb, nexthdr, 0, -1);
+}
+EXPORT_SYMBOL(xfrm_input_resume);
+
 void __init xfrm_input_init(void)
 {
        secpath_cachep = kmem_cache_create("secpath_cache",