timewait_sock: Create and use getpeer op.

The only thing AF-specific about remembering the timestamp
for a time-wait TCP socket is getting the peer.

Abstract that behind a new timewait_sock_ops vector.

Support for real IPV6 sockets is not filled in yet, but
curiously this makes timewait recycling start to work
for v4-mapped ipv6 sockets.

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 19 insertions, 7 deletions

diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index e394d0029d8..5f73a1808e3 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -906,12 +906,6 @@ static const struct tcp_request_sock_ops tcp_request_sock_ipv6_ops = {
 };
 #endif
 
-static struct timewait_sock_ops tcp6_timewait_sock_ops = {
-        .twsk_obj_size  = sizeof(struct tcp6_timewait_sock),
-        .twsk_unique    = tcp_twsk_unique,
-        .twsk_destructor= tcp_twsk_destructor,
-};
-
 static void __tcp_v6_send_check(struct sk_buff *skb,
                                 struct in6_addr *saddr, struct in6_addr *daddr)
 {
@@ -1818,12 +1812,30 @@ do_time_wait:
         goto discard_it;
 }
 
-struct inet_peer *tcp_v6_get_peer(struct sock *sk, bool *release_it)
+static struct inet_peer *tcp_v6_get_peer(struct sock *sk, bool *release_it)
+{
+        /* Alas, not yet... */
+        return NULL;
+}
+
+static void *tcp_v6_tw_get_peer(struct sock *sk)
 {
+        struct inet_timewait_sock *tw = inet_twsk(sk);
+
+        if (tw->tw_family == AF_INET)
+                return tcp_v4_tw_get_peer(sk);
+
         /* Alas, not yet... */
         return NULL;
 }
 
+static struct timewait_sock_ops tcp6_timewait_sock_ops = {
+        .twsk_obj_size  = sizeof(struct tcp6_timewait_sock),
+        .twsk_unique    = tcp_twsk_unique,
+        .twsk_destructor= tcp_twsk_destructor,
+        .twsk_getpeer   = tcp_v6_tw_get_peer,
+};
+
 static const struct inet_connection_sock_af_ops ipv6_specific = {
         .queue_xmit        = inet6_csk_xmit,
         .send_check        = tcp_v6_send_check,