tcp: add route_req method to tcp_request_sock_ops

Create wrappers with same signature for the IPv4/IPv6 request routing
calls and use these wrappers (via route_req method from
tcp_request_sock_ops) in tcp_v4_conn_request and tcp_v6_conn_request
with the purpose of unifying the two functions in a later patch.

We can later drop the wrapper functions and modify inet_csk_route_req
and inet6_cks_route_req to use the same signature.

Signed-off-by: Octavian Purdila <octavian.purdila@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/tcp.h b/include/net/tcp.h
index 086d00ec6d8bea41183bf9db8b290b6ec3254316..59fcc5934c79f3a8d7e16718154cb7a76bdfe3d4 100644 (file)
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -1605,6 +1605,9 @@ struct tcp_request_sock_ops {
        __u32 (*cookie_init_seq)(struct sock *sk, const struct sk_buff *skb,
                                 __u16 *mss);
 #endif
+       struct dst_entry *(*route_req)(struct sock *sk, struct flowi *fl,
+                                      const struct request_sock *req,
+                                      bool *strict);
 };
 
 #ifdef CONFIG_SYN_COOKIES

diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 8c69e44c287bacf71a9eaba9cc611a53456be6ea..54fbbd8b4fcda88fadd8399245995e9e40fbf77a 100644 (file)
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -1248,6 +1248,22 @@ static void tcp_v4_init_req(struct request_sock *req, struct sock *sk,
        ireq->opt = tcp_v4_save_options(skb);
 }
 
+static struct dst_entry *tcp_v4_route_req(struct sock *sk, struct flowi *fl,
+                                         const struct request_sock *req,
+                                         bool *strict)
+{
+       struct dst_entry *dst = inet_csk_route_req(sk, &fl->u.ip4, req);
+
+       if (strict) {
+               if (fl->u.ip4.daddr == inet_rsk(req)->ir_rmt_addr)
+                       *strict = true;
+               else
+                       *strict = false;
+       }
+
+       return dst;
+}
+
 struct request_sock_ops tcp_request_sock_ops __read_mostly = {
        .family         =       PF_INET,
        .obj_size       =       sizeof(struct tcp_request_sock),
@@ -1267,6 +1283,7 @@ static const struct tcp_request_sock_ops tcp_request_sock_ipv4_ops = {
 #ifdef CONFIG_SYN_COOKIES
        .cookie_init_seq =      cookie_v4_init_sequence,
 #endif
+       .route_req      =       tcp_v4_route_req,
 };
 
 int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
@@ -1346,11 +1363,13 @@ int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
                 * 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 = inet_csk_route_req(sk, &fl4, req)) != NULL &&
-                   fl4.daddr == saddr) {
-                       if (!tcp_peer_is_proven(req, dst, true)) {
+               if (tmp_opt.saw_tstamp && tcp_death_row.sysctl_tw_recycle) {
+                       bool strict;
+
+                       dst = af_ops->route_req(sk, (struct flowi *)&fl4, req,
+                                               &strict);
+                       if (dst && strict &&
+                           !tcp_peer_is_proven(req, dst, true)) {
                                NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_PAWSPASSIVEREJECTED);
                                goto drop_and_release;
                        }
@@ -1374,8 +1393,11 @@ int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
 
                isn = tcp_v4_init_sequence(skb);
        }
-       if (!dst && (dst = inet_csk_route_req(sk, &fl4, req)) == NULL)
-               goto drop_and_free;
+       if (!dst) {
+               dst = af_ops->route_req(sk, (struct flowi *)&fl4, req, NULL);
+               if (!dst)
+                       goto drop_and_free;
+       }
 
        tcp_rsk(req)->snt_isn = isn;
        tcp_openreq_init_rwin(req, sk, dst);

diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 17710cffddaa651dc7d182eb75f872200d19cae2..d780d88085664b70d08e2c7caf7e34881a9f3cb8 100644 (file)
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -745,6 +745,16 @@ static void tcp_v6_init_req(struct request_sock *req, struct sock *sk,
        }
 }
 
+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),
@@ -764,6 +774,7 @@ static const struct tcp_request_sock_ops tcp_request_sock_ipv6_ops = {
 #ifdef CONFIG_SYN_COOKIES
        .cookie_init_seq =      cookie_v6_init_sequence,
 #endif
+       .route_req      =       tcp_v6_route_req,
 };
 
 static void tcp_v6_send_response(struct sk_buff *skb, u32 seq, u32 ack, u32 win,
@@ -1078,10 +1089,10 @@ static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
                 * 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)) {
+               if (tmp_opt.saw_tstamp && tcp_death_row.sysctl_tw_recycle) {
+                       dst = af_ops->route_req(sk, (struct flowi *)&fl6, req,
+                                               NULL);
+                       if (dst && !tcp_peer_is_proven(req, dst, true)) {
                                NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_PAWSPASSIVEREJECTED);
                                goto drop_and_release;
                        }
@@ -1110,8 +1121,11 @@ 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;
+       if (!dst) {
+               dst = af_ops->route_req(sk, (struct flowi *)&fl6, req, NULL);
+               if (!dst)
+                       goto drop_and_free;
+       }
 
        tcp_rsk(req)->snt_isn = isn;
        tcp_openreq_init_rwin(req, sk, dst);