1 files changed, 76 insertions, 161 deletions

diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 229239ad96b1..29964c3d363c 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -198,6 +198,8 @@ static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
         sk->sk_v6_daddr = usin->sin6_addr;
         np->flow_label = fl6.flowlabel;
 
+        ip6_set_txhash(sk);
+
         /*
          *      TCP over IPv4
          */
@@ -470,13 +472,14 @@ out:
 
 
 static int tcp_v6_send_synack(struct sock *sk, struct dst_entry *dst,
-                              struct flowi6 *fl6,
+                              struct flowi *fl,
                               struct request_sock *req,
                               u16 queue_mapping,
                               struct tcp_fastopen_cookie *foc)
 {
         struct inet_request_sock *ireq = inet_rsk(req);
         struct ipv6_pinfo *np = inet6_sk(sk);
+        struct flowi6 *fl6 = &fl->u.ip6;
         struct sk_buff *skb;
         int err = -ENOMEM;
 
@@ -503,18 +506,6 @@ done:
         return err;
 }
 
-static int tcp_v6_rtx_synack(struct sock *sk, struct request_sock *req)
-{
-        struct flowi6 fl6;
-        int res;
-
-        res = tcp_v6_send_synack(sk, NULL, &fl6, req, 0, NULL);
-        if (!res) {
-                TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_RETRANSSEGS);
-                NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPSYNRETRANS);
-        }
-        return res;
-}
 
 static void tcp_v6_reqsk_destructor(struct request_sock *req)
 {
@@ -676,7 +667,8 @@ clear_hash_noput:
         return 1;
 }
 
-static int tcp_v6_inbound_md5_hash(struct sock *sk, const struct sk_buff *skb)
+static int __tcp_v6_inbound_md5_hash(struct sock *sk,
+                                     const struct sk_buff *skb)
 {
         const __u8 *hash_location = NULL;
         struct tcp_md5sig_key *hash_expected;
@@ -716,24 +708,80 @@ static int tcp_v6_inbound_md5_hash(struct sock *sk, const struct sk_buff *skb)
         }
         return 0;
 }
+
+static int tcp_v6_inbound_md5_hash(struct sock *sk, const struct sk_buff *skb)
+{
+        int ret;
+
+        rcu_read_lock();
+        ret = __tcp_v6_inbound_md5_hash(sk, skb);
+        rcu_read_unlock();
+
+        return ret;
+}
+
 #endif
 
+static void tcp_v6_init_req(struct request_sock *req, struct sock *sk,
+                            struct sk_buff *skb)
+{
+        struct inet_request_sock *ireq = inet_rsk(req);
+        struct ipv6_pinfo *np = inet6_sk(sk);
+
+        ireq->ir_v6_rmt_addr = ipv6_hdr(skb)->saddr;
+        ireq->ir_v6_loc_addr = ipv6_hdr(skb)->daddr;
+
+        ireq->ir_iif = sk->sk_bound_dev_if;
+
+        /* So that link locals have meaning */
+        if (!sk->sk_bound_dev_if &&
+            ipv6_addr_type(&ireq->ir_v6_rmt_addr) & IPV6_ADDR_LINKLOCAL)
+                ireq->ir_iif = inet6_iif(skb);
+
+        if (!TCP_SKB_CB(skb)->when &&
+            (ipv6_opt_accepted(sk, skb) || np->rxopt.bits.rxinfo ||
+             np->rxopt.bits.rxoinfo || np->rxopt.bits.rxhlim ||
+             np->rxopt.bits.rxohlim || np->repflow)) {
+                atomic_inc(&skb->users);
+                ireq->pktopts = skb;
+        }
+}
+
+static struct dst_entry *tcp_v6_route_req(struct sock *sk, struct flowi *fl,
+                                          const struct request_sock *req,
+                                          bool *strict)
+{
+        if (strict)
+                *strict = true;
+        return inet6_csk_route_req(sk, &fl->u.ip6, req);
+}
+
 struct request_sock_ops tcp6_request_sock_ops __read_mostly = {
         .family         =       AF_INET6,
         .obj_size       =       sizeof(struct tcp6_request_sock),
-        .rtx_syn_ack    =       tcp_v6_rtx_synack,
+        .rtx_syn_ack    =       tcp_rtx_synack,
         .send_ack       =       tcp_v6_reqsk_send_ack,
         .destructor     =       tcp_v6_reqsk_destructor,
         .send_reset     =       tcp_v6_send_reset,
         .syn_ack_timeout =      tcp_syn_ack_timeout,
 };
 
-#ifdef CONFIG_TCP_MD5SIG
 static const struct tcp_request_sock_ops tcp_request_sock_ipv6_ops = {
+        .mss_clamp      =       IPV6_MIN_MTU - sizeof(struct tcphdr) -
+                                sizeof(struct ipv6hdr),
+#ifdef CONFIG_TCP_MD5SIG
         .md5_lookup     =       tcp_v6_reqsk_md5_lookup,
         .calc_md5_hash  =       tcp_v6_md5_hash_skb,
-};
 #endif
+        .init_req       =       tcp_v6_init_req,
+#ifdef CONFIG_SYN_COOKIES
+        .cookie_init_seq =      cookie_v6_init_sequence,
+#endif
+        .route_req      =       tcp_v6_route_req,
+        .init_seq       =       tcp_v6_init_sequence,
+        .send_synack    =       tcp_v6_send_synack,
+        .queue_hash_add =       inet6_csk_reqsk_queue_hash_add,
+};
 
 static void tcp_v6_send_response(struct sk_buff *skb, u32 seq, u32 ack, u32 win,
                                  u32 tsval, u32 tsecr, int oif,
@@ -973,153 +1021,17 @@ static struct sock *tcp_v6_hnd_req(struct sock *sk, struct sk_buff *skb)
         return sk;
 }
 
-/* FIXME: this is substantially similar to the ipv4 code.
- * Can some kind of merge be done? -- erics
- */
 static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
 {
-        struct tcp_options_received tmp_opt;
-        struct request_sock *req;
-        struct inet_request_sock *ireq;
-        struct ipv6_pinfo *np = inet6_sk(sk);
-        struct tcp_sock *tp = tcp_sk(sk);
-        __u32 isn = TCP_SKB_CB(skb)->when;
-        struct dst_entry *dst = NULL;
-        struct tcp_fastopen_cookie foc = { .len = -1 };
-        bool want_cookie = false, fastopen;
-        struct flowi6 fl6;
-        int err;
-
         if (skb->protocol == htons(ETH_P_IP))
                 return tcp_v4_conn_request(sk, skb);
 
         if (!ipv6_unicast_destination(skb))
                 goto drop;
 
-        if ((sysctl_tcp_syncookies == 2 ||
-             inet_csk_reqsk_queue_is_full(sk)) && !isn) {
-                want_cookie = tcp_syn_flood_action(sk, skb, "TCPv6");
-                if (!want_cookie)
-                        goto drop;
-        }
-
-        if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1) {
-                NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
-                goto drop;
-        }
-
-        req = inet6_reqsk_alloc(&tcp6_request_sock_ops);
-        if (req == NULL)
-                goto drop;
-
-#ifdef CONFIG_TCP_MD5SIG
-        tcp_rsk(req)->af_specific = &tcp_request_sock_ipv6_ops;
-#endif
-
-        tcp_clear_options(&tmp_opt);
-        tmp_opt.mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) - sizeof(struct ipv6hdr);
-        tmp_opt.user_mss = tp->rx_opt.user_mss;
-        tcp_parse_options(skb, &tmp_opt, 0, want_cookie ? NULL : &foc);
-
-        if (want_cookie && !tmp_opt.saw_tstamp)
-                tcp_clear_options(&tmp_opt);
-
-        tmp_opt.tstamp_ok = tmp_opt.saw_tstamp;
-        tcp_openreq_init(req, &tmp_opt, skb);
-
-        ireq = inet_rsk(req);
-        ireq->ir_v6_rmt_addr = ipv6_hdr(skb)->saddr;
-        ireq->ir_v6_loc_addr = ipv6_hdr(skb)->daddr;
-        if (!want_cookie || tmp_opt.tstamp_ok)
-                TCP_ECN_create_request(req, skb, sock_net(sk));
-
-        ireq->ir_iif = sk->sk_bound_dev_if;
-        ireq->ir_mark = inet_request_mark(sk, skb);
-
-        /* So that link locals have meaning */
-        if (!sk->sk_bound_dev_if &&
-            ipv6_addr_type(&ireq->ir_v6_rmt_addr) & IPV6_ADDR_LINKLOCAL)
-                ireq->ir_iif = inet6_iif(skb);
-
-        if (!isn) {
-                if (ipv6_opt_accepted(sk, skb) ||
-                    np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo ||
-                    np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim ||
-                    np->repflow) {
-                        atomic_inc(&skb->users);
-                        ireq->pktopts = skb;
-                }
+        return tcp_conn_request(&tcp6_request_sock_ops,
+                                &tcp_request_sock_ipv6_ops, sk, skb);
 
-                if (want_cookie) {
-                        isn = cookie_v6_init_sequence(sk, skb, &req->mss);
-                        req->cookie_ts = tmp_opt.tstamp_ok;
-                        goto have_isn;
-                }
-
-                /* VJ's idea. We save last timestamp seen
-                 * from the destination in peer table, when entering
-                 * state TIME-WAIT, and check against it before
-                 * accepting new connection request.
-                 *
-                 * If "isn" is not zero, this request hit alive
-                 * timewait bucket, so that all the necessary checks
-                 * are made in the function processing timewait state.
-                 */
-                if (tmp_opt.saw_tstamp &&
-                    tcp_death_row.sysctl_tw_recycle &&
-                    (dst = inet6_csk_route_req(sk, &fl6, req)) != NULL) {
-                        if (!tcp_peer_is_proven(req, dst, true)) {
-                                NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_PAWSPASSIVEREJECTED);
-                                goto drop_and_release;
-                        }
-                }
-                /* Kill the following clause, if you dislike this way. */
-                else if (!sysctl_tcp_syncookies &&
-                         (sysctl_max_syn_backlog - inet_csk_reqsk_queue_len(sk) <
-                          (sysctl_max_syn_backlog >> 2)) &&
-                         !tcp_peer_is_proven(req, dst, false)) {
-                        /* Without syncookies last quarter of
-                         * backlog is filled with destinations,
-                         * proven to be alive.
-                         * It means that we continue to communicate
-                         * to destinations, already remembered
-                         * to the moment of synflood.
-                         */
-                        LIMIT_NETDEBUG(KERN_DEBUG "TCP: drop open request from %pI6/%u\n",
-                                       &ireq->ir_v6_rmt_addr, ntohs(tcp_hdr(skb)->source));
-                        goto drop_and_release;
-                }
-
-                isn = tcp_v6_init_sequence(skb);
-        }
-have_isn:
-
-        if (security_inet_conn_request(sk, skb, req))
-                goto drop_and_release;
-
-        if (!dst && (dst = inet6_csk_route_req(sk, &fl6, req)) == NULL)
-                goto drop_and_free;
-
-        tcp_rsk(req)->snt_isn = isn;
-        tcp_rsk(req)->snt_synack = tcp_time_stamp;
-        tcp_openreq_init_rwin(req, sk, dst);
-        fastopen = !want_cookie &&
-                   tcp_try_fastopen(sk, skb, req, &foc, dst);
-        err = tcp_v6_send_synack(sk, dst, &fl6, req,
-                                 skb_get_queue_mapping(skb), &foc);
-        if (!fastopen) {
-                if (err || want_cookie)
-                        goto drop_and_free;
-
-                tcp_rsk(req)->listener = NULL;
-                inet6_csk_reqsk_queue_hash_add(sk, req, TCP_TIMEOUT_INIT);
-        }
-        return 0;
-
-drop_and_release:
-        dst_release(dst);
-drop_and_free:
-        reqsk_free(req);
 drop:
         NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS);
         return 0; /* don't send reset */
@@ -1235,6 +1147,8 @@ static struct sock *tcp_v6_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
         newsk->sk_v6_rcv_saddr = ireq->ir_v6_loc_addr;
         newsk->sk_bound_dev_if = ireq->ir_iif;
 
+        ip6_set_txhash(newsk);
+
         /* Now IPv6 options...
 
            First: no IPv4 options.
@@ -1346,11 +1260,6 @@ static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
         if (skb->protocol == htons(ETH_P_IP))
                 return tcp_v4_do_rcv(sk, skb);
 
-#ifdef CONFIG_TCP_MD5SIG
-        if (tcp_v6_inbound_md5_hash(sk, skb))
-                goto discard;
-#endif
-
         if (sk_filter(sk, skb))
                 goto discard;
 
@@ -1523,6 +1432,11 @@ process:
         if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
                 goto discard_and_relse;
 
+#ifdef CONFIG_TCP_MD5SIG
+        if (tcp_v6_inbound_md5_hash(sk, skb))
+                goto discard_and_relse;
+#endif
+
         if (sk_filter(sk, skb))
                 goto discard_and_relse;
 
@@ -1681,6 +1595,7 @@ static const struct inet_connection_sock_af_ops ipv6_specific = {
         .compat_setsockopt = compat_ipv6_setsockopt,
         .compat_getsockopt = compat_ipv6_getsockopt,
 #endif
+        .mtu_reduced       = tcp_v6_mtu_reduced,
 };
 
 #ifdef CONFIG_TCP_MD5SIG
@@ -1711,6 +1626,7 @@ static const struct inet_connection_sock_af_ops ipv6_mapped = {
         .compat_setsockopt = compat_ipv6_setsockopt,
         .compat_getsockopt = compat_ipv6_getsockopt,
 #endif
+        .mtu_reduced       = tcp_v4_mtu_reduced,
 };
 
 #ifdef CONFIG_TCP_MD5SIG
@@ -1950,7 +1866,6 @@ struct proto tcpv6_prot = {
         .sendpage               = tcp_sendpage,
         .backlog_rcv            = tcp_v6_do_rcv,
         .release_cb             = tcp_release_cb,
-        .mtu_reduced            = tcp_v6_mtu_reduced,
         .hash                   = tcp_v6_hash,
         .unhash                 = inet_unhash,
         .get_port               = inet_csk_get_port,