Commit ccb7c410 authored by David S. Miller's avatar David S. Miller
Browse files

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: default avatarDavid S. Miller <davem@davemloft.net>
parent 4399ce40

include/net/tcp.h

+1 −0
Original line number Diff line number Diff line
@@ -313,6 +313,7 @@ extern void tcp_shutdown (struct sock *sk, int how); 
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);

include/net/timewait_sock.h

+8 −0
Original line number Diff line number Diff line
@@ -21,6 +21,7 @@ struct timewait_sock_ops { 
	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)
@@ -39,4 +40,11 @@ static inline void twsk_destructor(struct sock *sk) 
		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 */

net/ipv4/tcp_ipv4.c

+11 −22
Original line number Diff line number Diff line
@@ -1210,12 +1210,6 @@ static const struct tcp_request_sock_ops tcp_request_sock_ipv4_ops = { 
};

#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 @@ struct inet_peer *tcp_v4_get_peer(struct sock *sk, bool *release_it) 
}

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);



	if (peer) {

		const struct tcp_timewait_sock *tcptw = tcp_twsk((struct sock *)tw);

	struct inet_timewait_sock *tw = inet_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 inet_getpeer_v4(tw->tw_daddr, 1);

}

EXPORT_SYMBOL(tcp_v4_tw_get_peer);



	return 0;

}

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,

net/ipv4/tcp_minisocks.c

+24 −8
Original line number Diff line number Diff line
@@ -78,6 +78,27 @@ static int tcp_remember_stamp(struct sock *sk) 
	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 @@ kill_with_rst: 
			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

net/ipv6/tcp_ipv6.c

+19 −7
Original line number Diff line number Diff line
@@ -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,

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