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>

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>
David S. Miller
1 parent 4399ce402c
Showing 5 changed files with 63 additions and 37 deletions Side-by-side Diff
include/net/tcp.h
include/net/timewait_sock.h
net/ipv4/tcp_ipv4.c
net/ipv4/tcp_minisocks.c
net/ipv6/tcp_ipv6.c
@@ -313,6 +313,7 @@
 extern int tcp_v4_rcv(struct sk_buff *skb);
  
 extern struct inet_peer *tcp_v4_get_peer(struct sock *sk, bool *release_it);
+extern void *tcp_v4_tw_get_peer(struct sock *sk);
 extern int tcp_v4_tw_remember_stamp(struct inet_timewait_sock *tw);
 extern int tcp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 		       size_t size);
@@ -21,6 +21,7 @@
 	int		(*twsk_unique)(struct sock *sk,
 				       struct sock *sktw, void *twp);
 	void		(*twsk_destructor)(struct sock *sk);
+	void		*(*twsk_getpeer)(struct sock *sk);
 };
  
 static inline int twsk_unique(struct sock *sk, struct sock *sktw, void *twp)
@@ -37,6 +38,13 @@
 	BUG_ON(sk->sk_prot->twsk_prot == NULL);
 	if (sk->sk_prot->twsk_prot->twsk_destructor != NULL)
 		sk->sk_prot->twsk_prot->twsk_destructor(sk);
+}
+
+static inline void *twsk_getpeer(struct sock *sk)
+{
+	if (sk->sk_prot->twsk_prot->twsk_getpeer)
+		return sk->sk_prot->twsk_prot->twsk_getpeer(sk);
+	return NULL;
 }
  
 #endif /* _TIMEWAIT_SOCK_H */
@@ -1210,12 +1210,6 @@
 };
 #endif
  
-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,
-};
-
 int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
 {
 	struct tcp_extend_values tmp_ext;
  
  
  
@@ -1783,25 +1777,20 @@
 }
 EXPORT_SYMBOL(tcp_v4_get_peer);
  
-int tcp_v4_tw_remember_stamp(struct inet_timewait_sock *tw)
+void *tcp_v4_tw_get_peer(struct sock *sk)
 {
-	struct inet_peer *peer = inet_getpeer_v4(tw->tw_daddr, 1);
+	struct inet_timewait_sock *tw = inet_twsk(sk);
  
-	if (peer) {
-		const struct tcp_timewait_sock *tcptw = tcp_twsk((struct sock *)tw);
-
-		if ((s32)(peer->tcp_ts - tcptw->tw_ts_recent) <= 0 ||
-		    ((u32)get_seconds() - peer->tcp_ts_stamp > TCP_PAWS_MSL &&
-		     peer->tcp_ts_stamp <= (u32)tcptw->tw_ts_recent_stamp)) {
-			peer->tcp_ts_stamp = (u32)tcptw->tw_ts_recent_stamp;
-			peer->tcp_ts	   = tcptw->tw_ts_recent;
-		}
-		inet_putpeer(peer);
-		return 1;
-	}
-
-	return 0;
+	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 = {
 	.queue_xmit	   = ip_queue_xmit,
@@ -78,6 +78,27 @@
 	return 0;
 }
  
+static int tcp_tw_remember_stamp(struct inet_timewait_sock *tw)
+{
+	struct sock *sk = (struct sock *) tw;
+	struct inet_peer *peer;
+
+	peer = twsk_getpeer(sk);
+	if (peer) {
+		const struct tcp_timewait_sock *tcptw = tcp_twsk(sk);
+
+		if ((s32)(peer->tcp_ts - tcptw->tw_ts_recent) <= 0 ||
+		    ((u32)get_seconds() - peer->tcp_ts_stamp > TCP_PAWS_MSL &&
+		     peer->tcp_ts_stamp <= (u32)tcptw->tw_ts_recent_stamp)) {
+			peer->tcp_ts_stamp = (u32)tcptw->tw_ts_recent_stamp;
+			peer->tcp_ts	   = tcptw->tw_ts_recent;
+		}
+		inet_putpeer(peer);
+		return 1;
+	}
+	return 0;
+}
+
 static __inline__ int tcp_in_window(u32 seq, u32 end_seq, u32 s_win, u32 e_win)
 {
 	if (seq == s_win)
@@ -178,14 +199,9 @@
 			tcptw->tw_ts_recent	  = tmp_opt.rcv_tsval;
 		}
  
-		/* I am shamed, but failed to make it more elegant.
-		 * Yes, it is direct reference to IP, which is impossible
-		 * to generalize to IPv6. Taking into account that IPv6
-		 * do not understand recycling in any case, it not
-		 * a big problem in practice. --ANK */
-		if (tw->tw_family == AF_INET &&
-		    tcp_death_row.sysctl_tw_recycle && tcptw->tw_ts_recent_stamp &&
-		    tcp_v4_tw_remember_stamp(tw))
+		if (tcp_death_row.sysctl_tw_recycle &&
+		    tcptw->tw_ts_recent_stamp &&
+		    tcp_tw_remember_stamp(tw))
 			inet_twsk_schedule(tw, &tcp_death_row, tw->tw_timeout,
 					   TCP_TIMEWAIT_LEN);
 		else
@@ -906,12 +906,6 @@
 };
 #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)
 {
  
@@ -1818,11 +1812,29 @@
 	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,
...	...	@@ -313,6 +313,7 @@
313	313	extern int tcp_v4_rcv(struct sk_buff *skb);
314	314
315	315	extern struct inet_peer tcp_v4_get_peer(struct sock sk, bool *release_it);
	316	+extern void tcp_v4_tw_get_peer(struct sock sk);
316	317	extern int tcp_v4_tw_remember_stamp(struct inet_timewait_sock *tw);
317	318	extern int tcp_sendmsg(struct kiocb iocb, struct sock sk, struct msghdr *msg,
318	319	size_t size);
...	...	@@ -21,6 +21,7 @@
21	21	int (twsk_unique)(struct sock sk,
22	22	struct sock sktw, void twp);
23	23	void (twsk_destructor)(struct sock sk);
	24	+ void (twsk_getpeer)(struct sock *sk);
24	25	};
25	26
26	27	static inline int twsk_unique(struct sock sk, struct sock sktw, void *twp)
...	...	@@ -37,6 +38,13 @@
37	38	BUG_ON(sk->sk_prot->twsk_prot == NULL);
38	39	if (sk->sk_prot->twsk_prot->twsk_destructor != NULL)
39	40	sk->sk_prot->twsk_prot->twsk_destructor(sk);
	41	+}
	42	+
	43	+static inline void twsk_getpeer(struct sock sk)
	44	+{
	45	+ if (sk->sk_prot->twsk_prot->twsk_getpeer)
	46	+ return sk->sk_prot->twsk_prot->twsk_getpeer(sk);
	47	+ return NULL;
40	48	}
41	49
42	50	#endif /* _TIMEWAIT_SOCK_H */
...	...	@@ -1210,12 +1210,6 @@
1210	1210	};
1211	1211	#endif
1212	1212
1213		-static struct timewait_sock_ops tcp_timewait_sock_ops = {
1214		- .twsk_obj_size = sizeof(struct tcp_timewait_sock),
1215		- .twsk_unique = tcp_twsk_unique,
1216		- .twsk_destructor= tcp_twsk_destructor,
1217		-};
1218		-
1219	1213	int tcp_v4_conn_request(struct sock sk, struct sk_buff skb)
1220	1214	{
1221	1215	struct tcp_extend_values tmp_ext;
1222	1216
1223	1217
1224	1218
...	...	@@ -1783,25 +1777,20 @@
1783	1777	}
1784	1778	EXPORT_SYMBOL(tcp_v4_get_peer);
1785	1779
1786		-int tcp_v4_tw_remember_stamp(struct inet_timewait_sock *tw)
	1780	+void tcp_v4_tw_get_peer(struct sock sk)
1787	1781	{
1788		- struct inet_peer *peer = inet_getpeer_v4(tw->tw_daddr, 1);
	1782	+ struct inet_timewait_sock *tw = inet_twsk(sk);
1789	1783
1790		- if (peer) {
1791		- const struct tcp_timewait_sock tcptw = tcp_twsk((struct sock )tw);
1792		-
1793		- if ((s32)(peer->tcp_ts - tcptw->tw_ts_recent) <= 0 \|\|
1794		- ((u32)get_seconds() - peer->tcp_ts_stamp > TCP_PAWS_MSL &&
1795		- peer->tcp_ts_stamp <= (u32)tcptw->tw_ts_recent_stamp)) {
1796		- peer->tcp_ts_stamp = (u32)tcptw->tw_ts_recent_stamp;
1797		- peer->tcp_ts = tcptw->tw_ts_recent;
1798		- }
1799		- inet_putpeer(peer);
1800		- return 1;
1801		- }
1802		-
1803		- return 0;
	1784	+ return inet_getpeer_v4(tw->tw_daddr, 1);
1804	1785	}
	1786	+EXPORT_SYMBOL(tcp_v4_tw_get_peer);
	1787	+
	1788	+static struct timewait_sock_ops tcp_timewait_sock_ops = {
	1789	+ .twsk_obj_size = sizeof(struct tcp_timewait_sock),
	1790	+ .twsk_unique = tcp_twsk_unique,
	1791	+ .twsk_destructor= tcp_twsk_destructor,
	1792	+ .twsk_getpeer = tcp_v4_tw_get_peer,
	1793	+};
1805	1794
1806	1795	const struct inet_connection_sock_af_ops ipv4_specific = {
1807	1796	.queue_xmit = ip_queue_xmit,
...	...	@@ -78,6 +78,27 @@
78	78	return 0;
79	79	}
80	80
	81	+static int tcp_tw_remember_stamp(struct inet_timewait_sock *tw)
	82	+{
	83	+ struct sock sk = (struct sock ) tw;
	84	+ struct inet_peer *peer;
	85	+
	86	+ peer = twsk_getpeer(sk);
	87	+ if (peer) {
	88	+ const struct tcp_timewait_sock *tcptw = tcp_twsk(sk);
	89	+
	90	+ if ((s32)(peer->tcp_ts - tcptw->tw_ts_recent) <= 0 \|\|
	91	+ ((u32)get_seconds() - peer->tcp_ts_stamp > TCP_PAWS_MSL &&
	92	+ peer->tcp_ts_stamp <= (u32)tcptw->tw_ts_recent_stamp)) {
	93	+ peer->tcp_ts_stamp = (u32)tcptw->tw_ts_recent_stamp;
	94	+ peer->tcp_ts = tcptw->tw_ts_recent;
	95	+ }
	96	+ inet_putpeer(peer);
	97	+ return 1;
	98	+ }
	99	+ return 0;
	100	+}
	101	+
81	102	static __inline__ int tcp_in_window(u32 seq, u32 end_seq, u32 s_win, u32 e_win)
82	103	{
83	104	if (seq == s_win)
...	...	@@ -178,14 +199,9 @@
178	199	tcptw->tw_ts_recent = tmp_opt.rcv_tsval;
179	200	}
180	201
181		- /* I am shamed, but failed to make it more elegant.
182		- * Yes, it is direct reference to IP, which is impossible
183		- * to generalize to IPv6. Taking into account that IPv6
184		- * do not understand recycling in any case, it not
185		- * a big problem in practice. --ANK */
186		- if (tw->tw_family == AF_INET &&
187		- tcp_death_row.sysctl_tw_recycle && tcptw->tw_ts_recent_stamp &&
188		- tcp_v4_tw_remember_stamp(tw))
	202	+ if (tcp_death_row.sysctl_tw_recycle &&
	203	+ tcptw->tw_ts_recent_stamp &&
	204	+ tcp_tw_remember_stamp(tw))
189	205	inet_twsk_schedule(tw, &tcp_death_row, tw->tw_timeout,
190	206	TCP_TIMEWAIT_LEN);
191	207	else
...	...	@@ -906,12 +906,6 @@
906	906	};
907	907	#endif
908	908
909		-static struct timewait_sock_ops tcp6_timewait_sock_ops = {
910		- .twsk_obj_size = sizeof(struct tcp6_timewait_sock),
911		- .twsk_unique = tcp_twsk_unique,
912		- .twsk_destructor= tcp_twsk_destructor,
913		-};
914		-
915	909	static void __tcp_v6_send_check(struct sk_buff *skb,
916	910	struct in6_addr saddr, struct in6_addr daddr)
917	911	{
918	912
...	...	@@ -1818,11 +1812,29 @@
1818	1812	goto discard_it;
1819	1813	}
1820	1814
1821		-struct inet_peer tcp_v6_get_peer(struct sock sk, bool *release_it)
	1815	+static struct inet_peer tcp_v6_get_peer(struct sock sk, bool *release_it)
1822	1816	{
1823	1817	/* Alas, not yet... */
1824	1818	return NULL;
1825	1819	}
	1820	+
	1821	+static void tcp_v6_tw_get_peer(struct sock sk)
	1822	+{
	1823	+ struct inet_timewait_sock *tw = inet_twsk(sk);
	1824	+
	1825	+ if (tw->tw_family == AF_INET)
	1826	+ return tcp_v4_tw_get_peer(sk);
	1827	+
	1828	+ /* Alas, not yet... */
	1829	+ return NULL;
	1830	+}
	1831	+
	1832	+static struct timewait_sock_ops tcp6_timewait_sock_ops = {
	1833	+ .twsk_obj_size = sizeof(struct tcp6_timewait_sock),
	1834	+ .twsk_unique = tcp_twsk_unique,
	1835	+ .twsk_destructor= tcp_twsk_destructor,
	1836	+ .twsk_getpeer = tcp_v6_tw_get_peer,
	1837	+};
1826	1838
1827	1839	static const struct inet_connection_sock_af_ops ipv6_specific = {
1828	1840	.queue_xmit = inet6_csk_xmit,