ipv4: tcp: dont cache output dst for syncookies

[linux-2.6-block.git] / net / ipv4 / tcp_ipv4.c

diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index a43b87dfe800c043c7fcc65af316b4d193ab3455..b52934f5334e2f56089d61d288af07108acc6104 100644 (file)
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -824,7 +824,9 @@ static void tcp_v4_reqsk_send_ack(struct sock *sk, struct sk_buff *skb,
  */
 static int tcp_v4_send_synack(struct sock *sk, struct dst_entry *dst,
                              struct request_sock *req,
-                             struct request_values *rvp)
+                             struct request_values *rvp,
+                             u16 queue_mapping,
+                             bool nocache)
 {
        const struct inet_request_sock *ireq = inet_rsk(req);
        struct flowi4 fl4;
@@ -832,7 +834,7 @@ static int tcp_v4_send_synack(struct sock *sk, struct dst_entry *dst,
        struct sk_buff * skb;
 
        /* First, grab a route. */
-       if (!dst && (dst = inet_csk_route_req(sk, &fl4, req)) == NULL)
+       if (!dst && (dst = inet_csk_route_req(sk, &fl4, req, nocache)) == NULL)
                return -1;
 
        skb = tcp_make_synack(sk, dst, req, rvp);
@@ -840,13 +842,13 @@ static int tcp_v4_send_synack(struct sock *sk, struct dst_entry *dst,
        if (skb) {
                __tcp_v4_send_check(skb, ireq->loc_addr, ireq->rmt_addr);
 
+               skb_set_queue_mapping(skb, queue_mapping);
                err = ip_build_and_send_pkt(skb, sk, ireq->loc_addr,
                                            ireq->rmt_addr,
                                            ireq->opt);
                err = net_xmit_eval(err);
        }
 
-       dst_release(dst);
        return err;
 }
 
@@ -854,7 +856,7 @@ static int tcp_v4_rtx_synack(struct sock *sk, struct request_sock *req,
                              struct request_values *rvp)
 {
        TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_RETRANSSEGS);
-       return tcp_v4_send_synack(sk, NULL, req, rvp);
+       return tcp_v4_send_synack(sk, NULL, req, rvp, 0, false);
 }
 
 /*
@@ -1387,7 +1389,7 @@ int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
                 */
                if (tmp_opt.saw_tstamp &&
                    tcp_death_row.sysctl_tw_recycle &&
-                   (dst = inet_csk_route_req(sk, &fl4, req)) != NULL &&
+                   (dst = inet_csk_route_req(sk, &fl4, req, want_cookie)) != NULL &&
                    fl4.daddr == saddr &&
                    (peer = rt_get_peer((struct rtable *)dst, fl4.daddr)) != NULL) {
                        inet_peer_refcheck(peer);
@@ -1422,7 +1424,9 @@ int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
        tcp_rsk(req)->snt_synack = tcp_time_stamp;
 
        if (tcp_v4_send_synack(sk, dst, req,
-                              (struct request_values *)&tmp_ext) ||
+                              (struct request_values *)&tmp_ext,
+                              skb_get_queue_mapping(skb),
+                              want_cookie) ||
            want_cookie)
                goto drop_and_free;
 
@@ -1669,6 +1673,58 @@ csum_err:
 }
 EXPORT_SYMBOL(tcp_v4_do_rcv);
 
+int tcp_v4_early_demux(struct sk_buff *skb)
+{
+       struct net *net = dev_net(skb->dev);
+       const struct iphdr *iph;
+       const struct tcphdr *th;
+       struct net_device *dev;
+       struct sock *sk;
+       int err;
+
+       err = -ENOENT;
+       if (skb->pkt_type != PACKET_HOST)
+               goto out_err;
+
+       if (!pskb_may_pull(skb, ip_hdrlen(skb) + sizeof(struct tcphdr)))
+               goto out_err;
+
+       iph = ip_hdr(skb);
+       th = (struct tcphdr *) ((char *)iph + ip_hdrlen(skb));
+
+       if (th->doff < sizeof(struct tcphdr) / 4)
+               goto out_err;
+
+       if (!pskb_may_pull(skb, ip_hdrlen(skb) + th->doff * 4))
+               goto out_err;
+
+       dev = skb->dev;
+       sk = __inet_lookup_established(net, &tcp_hashinfo,
+                                      iph->saddr, th->source,
+                                      iph->daddr, th->dest,
+                                      dev->ifindex);
+       if (sk) {
+               skb->sk = sk;
+               skb->destructor = sock_edemux;
+               if (sk->sk_state != TCP_TIME_WAIT) {
+                       struct dst_entry *dst = sk->sk_rx_dst;
+                       if (dst)
+                               dst = dst_check(dst, 0);
+                       if (dst) {
+                               struct rtable *rt = (struct rtable *) dst;
+
+                               if (rt->rt_iif == dev->ifindex) {
+                                       skb_dst_set_noref(skb, dst);
+                                       err = 0;
+                               }
+                       }
+               }
+       }
+
+out_err:
+       return err;
+}
+
 /*
  *     From tcp_input.c
  */
@@ -1818,40 +1874,25 @@ do_time_wait:
        goto discard_it;
 }
 
-struct inet_peer *tcp_v4_get_peer(struct sock *sk, bool *release_it)
+struct inet_peer *tcp_v4_get_peer(struct sock *sk)
 {
        struct rtable *rt = (struct rtable *) __sk_dst_get(sk);
        struct inet_sock *inet = inet_sk(sk);
-       struct inet_peer *peer;
 
-       if (!rt ||
-           inet->cork.fl.u.ip4.daddr != inet->inet_daddr) {
-               peer = inet_getpeer_v4(inet->inet_daddr, 1);
-               *release_it = true;
-       } else {
-               if (!rt->peer)
-                       rt_bind_peer(rt, inet->inet_daddr, 1);
-               peer = rt->peer;
-               *release_it = false;
-       }
-
-       return peer;
+       /* If we don't have a valid cached route, or we're doing IP
+        * options which make the IPv4 header destination address
+        * different from our peer's, do not bother with this.
+        */
+       if (!rt || inet->cork.fl.u.ip4.daddr != inet->inet_daddr)
+               return NULL;
+       return rt_get_peer_create(rt, inet->inet_daddr);
 }
 EXPORT_SYMBOL(tcp_v4_get_peer);
 
-void *tcp_v4_tw_get_peer(struct sock *sk)
-{
-       const struct inet_timewait_sock *tw = inet_twsk(sk);
-
-       return inet_getpeer_v4(tw->tw_daddr, 1);
-}
-EXPORT_SYMBOL(tcp_v4_tw_get_peer);
-
 static struct timewait_sock_ops tcp_timewait_sock_ops = {
        .twsk_obj_size  = sizeof(struct tcp_timewait_sock),
        .twsk_unique    = tcp_twsk_unique,
        .twsk_destructor= tcp_twsk_destructor,
-       .twsk_getpeer   = tcp_v4_tw_get_peer,
 };
 
 const struct inet_connection_sock_af_ops ipv4_specific = {