tcp_ipv6.c 52.9 KB
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/*
 *	TCP over IPv6
 *	Linux INET6 implementation 
 *
 *	Authors:
 *	Pedro Roque		<roque@di.fc.ul.pt>	
 *
 *	$Id: tcp_ipv6.c,v 1.144 2002/02/01 22:01:04 davem Exp $
 *
 *	Based on: 
 *	linux/net/ipv4/tcp.c
 *	linux/net/ipv4/tcp_input.c
 *	linux/net/ipv4/tcp_output.c
 *
 *	Fixes:
 *	Hideaki YOSHIFUJI	:	sin6_scope_id support
 *	YOSHIFUJI Hideaki @USAGI and:	Support IPV6_V6ONLY socket option, which
 *	Alexey Kuznetsov		allow both IPv4 and IPv6 sockets to bind
 *					a single port at the same time.
 *	YOSHIFUJI Hideaki @USAGI:	convert /proc/net/tcp6 to seq_file.
 *
 *	This program is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU General Public License
 *      as published by the Free Software Foundation; either version
 *      2 of the License, or (at your option) any later version.
 */

#include <linux/module.h>
#include <linux/config.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/socket.h>
#include <linux/sockios.h>
#include <linux/net.h>
#include <linux/jiffies.h>
#include <linux/in.h>
#include <linux/in6.h>
#include <linux/netdevice.h>
#include <linux/init.h>
#include <linux/jhash.h>
#include <linux/ipsec.h>
#include <linux/times.h>

#include <linux/ipv6.h>
#include <linux/icmpv6.h>
#include <linux/random.h>

#include <net/tcp.h>
#include <net/ndisc.h>
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#include <net/inet6_hashtables.h>
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#include <net/ipv6.h>
#include <net/transp_v6.h>
#include <net/addrconf.h>
#include <net/ip6_route.h>
#include <net/ip6_checksum.h>
#include <net/inet_ecn.h>
#include <net/protocol.h>
#include <net/xfrm.h>
#include <net/addrconf.h>
#include <net/snmp.h>
#include <net/dsfield.h>

#include <asm/uaccess.h>

#include <linux/proc_fs.h>
#include <linux/seq_file.h>

static void	tcp_v6_send_reset(struct sk_buff *skb);
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static void	tcp_v6_reqsk_send_ack(struct sk_buff *skb, struct request_sock *req);
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static void	tcp_v6_send_check(struct sock *sk, struct tcphdr *th, int len, 
				  struct sk_buff *skb);

static int	tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb);
static int	tcp_v6_xmit(struct sk_buff *skb, int ipfragok);

static struct tcp_func ipv6_mapped;
static struct tcp_func ipv6_specific;

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static inline int tcp_v6_bind_conflict(const struct sock *sk,
				       const struct inet_bind_bucket *tb)
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{
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	const struct sock *sk2;
	const struct hlist_node *node;
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	/* We must walk the whole port owner list in this case. -DaveM */
	sk_for_each_bound(sk2, node, &tb->owners) {
		if (sk != sk2 &&
		    (!sk->sk_bound_dev_if ||
		     !sk2->sk_bound_dev_if ||
		     sk->sk_bound_dev_if == sk2->sk_bound_dev_if) &&
		    (!sk->sk_reuse || !sk2->sk_reuse ||
		     sk2->sk_state == TCP_LISTEN) &&
		     ipv6_rcv_saddr_equal(sk, sk2))
			break;
	}

	return node != NULL;
}

/* Grrr, addr_type already calculated by caller, but I don't want
 * to add some silly "cookie" argument to this method just for that.
 * But it doesn't matter, the recalculation is in the rarest path
 * this function ever takes.
 */
static int tcp_v6_get_port(struct sock *sk, unsigned short snum)
{
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	struct inet_bind_hashbucket *head;
	struct inet_bind_bucket *tb;
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	struct hlist_node *node;
	int ret;

	local_bh_disable();
	if (snum == 0) {
		int low = sysctl_local_port_range[0];
		int high = sysctl_local_port_range[1];
		int remaining = (high - low) + 1;
		int rover;

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		spin_lock(&tcp_hashinfo.portalloc_lock);
		if (tcp_hashinfo.port_rover < low)
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			rover = low;
		else
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			rover = tcp_hashinfo.port_rover;
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		do {	rover++;
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			if (rover > high)
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				rover = low;
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			head = &tcp_hashinfo.bhash[inet_bhashfn(rover, tcp_hashinfo.bhash_size)];
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			spin_lock(&head->lock);
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			inet_bind_bucket_for_each(tb, node, &head->chain)
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				if (tb->port == rover)
					goto next;
			break;
		next:
			spin_unlock(&head->lock);
		} while (--remaining > 0);
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		tcp_hashinfo.port_rover = rover;
		spin_unlock(&tcp_hashinfo.portalloc_lock);
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		/* Exhausted local port range during search?  It is not
		 * possible for us to be holding one of the bind hash
		 * locks if this test triggers, because if 'remaining'
		 * drops to zero, we broke out of the do/while loop at
		 * the top level, not from the 'break;' statement.
		 */
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		ret = 1;
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		if (unlikely(remaining <= 0))
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			goto fail;

		/* OK, here is the one we will use. */
		snum = rover;
	} else {
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		head = &tcp_hashinfo.bhash[inet_bhashfn(snum, tcp_hashinfo.bhash_size)];
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		spin_lock(&head->lock);
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		inet_bind_bucket_for_each(tb, node, &head->chain)
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			if (tb->port == snum)
				goto tb_found;
	}
	tb = NULL;
	goto tb_not_found;
tb_found:
	if (tb && !hlist_empty(&tb->owners)) {
		if (tb->fastreuse > 0 && sk->sk_reuse &&
		    sk->sk_state != TCP_LISTEN) {
			goto success;
		} else {
			ret = 1;
			if (tcp_v6_bind_conflict(sk, tb))
				goto fail_unlock;
		}
	}
tb_not_found:
	ret = 1;
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	if (tb == NULL) {
	       	tb = inet_bind_bucket_create(tcp_hashinfo.bind_bucket_cachep, head, snum);
		if (tb == NULL)
			goto fail_unlock;
	}
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	if (hlist_empty(&tb->owners)) {
		if (sk->sk_reuse && sk->sk_state != TCP_LISTEN)
			tb->fastreuse = 1;
		else
			tb->fastreuse = 0;
	} else if (tb->fastreuse &&
		   (!sk->sk_reuse || sk->sk_state == TCP_LISTEN))
		tb->fastreuse = 0;

success:
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	if (!inet_csk(sk)->icsk_bind_hash)
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		inet_bind_hash(sk, tb, snum);
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	BUG_TRAP(inet_csk(sk)->icsk_bind_hash == tb);
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	ret = 0;

fail_unlock:
	spin_unlock(&head->lock);
fail:
	local_bh_enable();
	return ret;
}

static __inline__ void __tcp_v6_hash(struct sock *sk)
{
	struct hlist_head *list;
	rwlock_t *lock;

	BUG_TRAP(sk_unhashed(sk));

	if (sk->sk_state == TCP_LISTEN) {
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		list = &tcp_hashinfo.listening_hash[inet_sk_listen_hashfn(sk)];
		lock = &tcp_hashinfo.lhash_lock;
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		inet_listen_wlock(&tcp_hashinfo);
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	} else {
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		sk->sk_hashent = inet6_sk_ehashfn(sk, tcp_hashinfo.ehash_size);
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		list = &tcp_hashinfo.ehash[sk->sk_hashent].chain;
		lock = &tcp_hashinfo.ehash[sk->sk_hashent].lock;
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		write_lock(lock);
	}

	__sk_add_node(sk, list);
	sock_prot_inc_use(sk->sk_prot);
	write_unlock(lock);
}


static void tcp_v6_hash(struct sock *sk)
{
	if (sk->sk_state != TCP_CLOSE) {
		struct tcp_sock *tp = tcp_sk(sk);

		if (tp->af_specific == &ipv6_mapped) {
			tcp_prot.hash(sk);
			return;
		}
		local_bh_disable();
		__tcp_v6_hash(sk);
		local_bh_enable();
	}
}

/*
 * Open request hash tables.
 */

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static u32 tcp_v6_synq_hash(const struct in6_addr *raddr, const u16 rport, const u32 rnd)
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{
	u32 a, b, c;

	a = raddr->s6_addr32[0];
	b = raddr->s6_addr32[1];
	c = raddr->s6_addr32[2];

	a += JHASH_GOLDEN_RATIO;
	b += JHASH_GOLDEN_RATIO;
	c += rnd;
	__jhash_mix(a, b, c);

	a += raddr->s6_addr32[3];
	b += (u32) rport;
	__jhash_mix(a, b, c);

	return c & (TCP_SYNQ_HSIZE - 1);
}

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static struct request_sock *tcp_v6_search_req(const struct sock *sk,
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					      struct request_sock ***prevp,
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					      __u16 rport,
					      struct in6_addr *raddr,
					      struct in6_addr *laddr,
					      int iif)
{
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	const struct inet_connection_sock *icsk = inet_csk(sk);
	struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt;
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	struct request_sock *req, **prev;  
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	for (prev = &lopt->syn_table[tcp_v6_synq_hash(raddr, rport, lopt->hash_rnd)];
	     (req = *prev) != NULL;
	     prev = &req->dl_next) {
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		const struct tcp6_request_sock *treq = tcp6_rsk(req);

		if (inet_rsk(req)->rmt_port == rport &&
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		    req->rsk_ops->family == AF_INET6 &&
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		    ipv6_addr_equal(&treq->rmt_addr, raddr) &&
		    ipv6_addr_equal(&treq->loc_addr, laddr) &&
		    (!treq->iif || treq->iif == iif)) {
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			BUG_TRAP(req->sk == NULL);
			*prevp = prev;
			return req;
		}
	}

	return NULL;
}

static __inline__ u16 tcp_v6_check(struct tcphdr *th, int len,
				   struct in6_addr *saddr, 
				   struct in6_addr *daddr, 
				   unsigned long base)
{
	return csum_ipv6_magic(saddr, daddr, len, IPPROTO_TCP, base);
}

static __u32 tcp_v6_init_sequence(struct sock *sk, struct sk_buff *skb)
{
	if (skb->protocol == htons(ETH_P_IPV6)) {
		return secure_tcpv6_sequence_number(skb->nh.ipv6h->daddr.s6_addr32,
						    skb->nh.ipv6h->saddr.s6_addr32,
						    skb->h.th->dest,
						    skb->h.th->source);
	} else {
		return secure_tcp_sequence_number(skb->nh.iph->daddr,
						  skb->nh.iph->saddr,
						  skb->h.th->dest,
						  skb->h.th->source);
	}
}

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static int __tcp_v6_check_established(struct sock *sk, const __u16 lport,
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				      struct inet_timewait_sock **twp)
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{
	struct inet_sock *inet = inet_sk(sk);
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	const struct ipv6_pinfo *np = inet6_sk(sk);
	const struct in6_addr *daddr = &np->rcv_saddr;
	const struct in6_addr *saddr = &np->daddr;
	const int dif = sk->sk_bound_dev_if;
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	const u32 ports = INET_COMBINED_PORTS(inet->dport, lport);
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	const int hash = inet6_ehashfn(daddr, inet->num, saddr, inet->dport,
				       tcp_hashinfo.ehash_size);
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	struct inet_ehash_bucket *head = &tcp_hashinfo.ehash[hash];
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	struct sock *sk2;
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	const struct hlist_node *node;
	struct inet_timewait_sock *tw;
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	write_lock(&head->lock);

	/* Check TIME-WAIT sockets first. */
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	sk_for_each(sk2, node, &(head + tcp_hashinfo.ehash_size)->chain) {
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		const struct tcp6_timewait_sock *tcp6tw = tcp6_twsk(sk2);

		tw = inet_twsk(sk2);
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		if(*((__u32 *)&(tw->tw_dport))	== ports	&&
		   sk2->sk_family		== PF_INET6	&&
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		   ipv6_addr_equal(&tcp6tw->tw_v6_daddr, saddr)	&&
		   ipv6_addr_equal(&tcp6tw->tw_v6_rcv_saddr, daddr)	&&
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		   sk2->sk_bound_dev_if == sk->sk_bound_dev_if) {
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			const struct tcp_timewait_sock *tcptw = tcp_twsk(sk2);
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			struct tcp_sock *tp = tcp_sk(sk);

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			if (tcptw->tw_ts_recent_stamp &&
			    (!twp ||
			     (sysctl_tcp_tw_reuse &&
			      xtime.tv_sec - tcptw->tw_ts_recent_stamp > 1))) {
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				/* See comment in tcp_ipv4.c */
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				tp->write_seq = tcptw->tw_snd_nxt + 65535 + 2;
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				if (!tp->write_seq)
					tp->write_seq = 1;
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				tp->rx_opt.ts_recent	   = tcptw->tw_ts_recent;
				tp->rx_opt.ts_recent_stamp = tcptw->tw_ts_recent_stamp;
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				sock_hold(sk2);
				goto unique;
			} else
				goto not_unique;
		}
	}
	tw = NULL;

	/* And established part... */
	sk_for_each(sk2, node, &head->chain) {
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		if (INET6_MATCH(sk2, saddr, daddr, ports, dif))
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			goto not_unique;
	}

unique:
	BUG_TRAP(sk_unhashed(sk));
	__sk_add_node(sk, &head->chain);
	sk->sk_hashent = hash;
	sock_prot_inc_use(sk->sk_prot);
	write_unlock(&head->lock);

	if (twp) {
		*twp = tw;
		NET_INC_STATS_BH(LINUX_MIB_TIMEWAITRECYCLED);
	} else if (tw) {
		/* Silly. Should hash-dance instead... */
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		inet_twsk_deschedule(tw, &tcp_death_row);
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		NET_INC_STATS_BH(LINUX_MIB_TIMEWAITRECYCLED);

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		inet_twsk_put(tw);
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	}
	return 0;

not_unique:
	write_unlock(&head->lock);
	return -EADDRNOTAVAIL;
}

static inline u32 tcpv6_port_offset(const struct sock *sk)
{
	const struct inet_sock *inet = inet_sk(sk);
	const struct ipv6_pinfo *np = inet6_sk(sk);

	return secure_tcpv6_port_ephemeral(np->rcv_saddr.s6_addr32,
					   np->daddr.s6_addr32,
					   inet->dport);
}

static int tcp_v6_hash_connect(struct sock *sk)
{
	unsigned short snum = inet_sk(sk)->num;
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 	struct inet_bind_hashbucket *head;
 	struct inet_bind_bucket *tb;
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	int ret;

 	if (!snum) {
 		int low = sysctl_local_port_range[0];
 		int high = sysctl_local_port_range[1];
		int range = high - low;
 		int i;
		int port;
		static u32 hint;
		u32 offset = hint + tcpv6_port_offset(sk);
		struct hlist_node *node;
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 		struct inet_timewait_sock *tw = NULL;
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 		local_bh_disable();
		for (i = 1; i <= range; i++) {
			port = low + (i + offset) % range;
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 			head = &tcp_hashinfo.bhash[inet_bhashfn(port, tcp_hashinfo.bhash_size)];
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 			spin_lock(&head->lock);

 			/* Does not bother with rcv_saddr checks,
 			 * because the established check is already
 			 * unique enough.
 			 */
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			inet_bind_bucket_for_each(tb, node, &head->chain) {
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 				if (tb->port == port) {
 					BUG_TRAP(!hlist_empty(&tb->owners));
 					if (tb->fastreuse >= 0)
 						goto next_port;
 					if (!__tcp_v6_check_established(sk,
									port,
									&tw))
 						goto ok;
 					goto next_port;
 				}
 			}

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 			tb = inet_bind_bucket_create(tcp_hashinfo.bind_bucket_cachep, head, port);
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 			if (!tb) {
 				spin_unlock(&head->lock);
 				break;
 			}
 			tb->fastreuse = -1;
 			goto ok;

 		next_port:
 			spin_unlock(&head->lock);
 		}
 		local_bh_enable();

 		return -EADDRNOTAVAIL;

ok:
		hint += i;

 		/* Head lock still held and bh's disabled */
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 		inet_bind_hash(sk, tb, port);
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		if (sk_unhashed(sk)) {
 			inet_sk(sk)->sport = htons(port);
 			__tcp_v6_hash(sk);
 		}
 		spin_unlock(&head->lock);

 		if (tw) {
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 			inet_twsk_deschedule(tw, &tcp_death_row);
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 			inet_twsk_put(tw);
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 		}

		ret = 0;
		goto out;
 	}

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 	head = &tcp_hashinfo.bhash[inet_bhashfn(snum, tcp_hashinfo.bhash_size)];
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 	tb   = inet_csk(sk)->icsk_bind_hash;
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	spin_lock_bh(&head->lock);

	if (sk_head(&tb->owners) == sk && !sk->sk_bind_node.next) {
		__tcp_v6_hash(sk);
		spin_unlock_bh(&head->lock);
		return 0;
	} else {
		spin_unlock(&head->lock);
		/* No definite answer... Walk to established hash table */
		ret = __tcp_v6_check_established(sk, snum, NULL);
out:
		local_bh_enable();
		return ret;
	}
}

static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr, 
			  int addr_len)
{
	struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr;
	struct inet_sock *inet = inet_sk(sk);
	struct ipv6_pinfo *np = inet6_sk(sk);
	struct tcp_sock *tp = tcp_sk(sk);
	struct in6_addr *saddr = NULL, *final_p = NULL, final;
	struct flowi fl;
	struct dst_entry *dst;
	int addr_type;
	int err;

	if (addr_len < SIN6_LEN_RFC2133) 
		return -EINVAL;

	if (usin->sin6_family != AF_INET6) 
		return(-EAFNOSUPPORT);

	memset(&fl, 0, sizeof(fl));

	if (np->sndflow) {
		fl.fl6_flowlabel = usin->sin6_flowinfo&IPV6_FLOWINFO_MASK;
		IP6_ECN_flow_init(fl.fl6_flowlabel);
		if (fl.fl6_flowlabel&IPV6_FLOWLABEL_MASK) {
			struct ip6_flowlabel *flowlabel;
			flowlabel = fl6_sock_lookup(sk, fl.fl6_flowlabel);
			if (flowlabel == NULL)
				return -EINVAL;
			ipv6_addr_copy(&usin->sin6_addr, &flowlabel->dst);
			fl6_sock_release(flowlabel);
		}
	}

	/*
  	 *	connect() to INADDR_ANY means loopback (BSD'ism).
  	 */
  	
  	if(ipv6_addr_any(&usin->sin6_addr))
		usin->sin6_addr.s6_addr[15] = 0x1; 

	addr_type = ipv6_addr_type(&usin->sin6_addr);

	if(addr_type & IPV6_ADDR_MULTICAST)
		return -ENETUNREACH;

	if (addr_type&IPV6_ADDR_LINKLOCAL) {
		if (addr_len >= sizeof(struct sockaddr_in6) &&
		    usin->sin6_scope_id) {
			/* If interface is set while binding, indices
			 * must coincide.
			 */
			if (sk->sk_bound_dev_if &&
			    sk->sk_bound_dev_if != usin->sin6_scope_id)
				return -EINVAL;

			sk->sk_bound_dev_if = usin->sin6_scope_id;
		}

		/* Connect to link-local address requires an interface */
		if (!sk->sk_bound_dev_if)
			return -EINVAL;
	}

	if (tp->rx_opt.ts_recent_stamp &&
	    !ipv6_addr_equal(&np->daddr, &usin->sin6_addr)) {
		tp->rx_opt.ts_recent = 0;
		tp->rx_opt.ts_recent_stamp = 0;
		tp->write_seq = 0;
	}

	ipv6_addr_copy(&np->daddr, &usin->sin6_addr);
	np->flow_label = fl.fl6_flowlabel;

	/*
	 *	TCP over IPv4
	 */

	if (addr_type == IPV6_ADDR_MAPPED) {
		u32 exthdrlen = tp->ext_header_len;
		struct sockaddr_in sin;

		SOCK_DEBUG(sk, "connect: ipv4 mapped\n");

		if (__ipv6_only_sock(sk))
			return -ENETUNREACH;

		sin.sin_family = AF_INET;
		sin.sin_port = usin->sin6_port;
		sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3];

		tp->af_specific = &ipv6_mapped;
		sk->sk_backlog_rcv = tcp_v4_do_rcv;

		err = tcp_v4_connect(sk, (struct sockaddr *)&sin, sizeof(sin));

		if (err) {
			tp->ext_header_len = exthdrlen;
			tp->af_specific = &ipv6_specific;
			sk->sk_backlog_rcv = tcp_v6_do_rcv;
			goto failure;
		} else {
			ipv6_addr_set(&np->saddr, 0, 0, htonl(0x0000FFFF),
				      inet->saddr);
			ipv6_addr_set(&np->rcv_saddr, 0, 0, htonl(0x0000FFFF),
				      inet->rcv_saddr);
		}

		return err;
	}

	if (!ipv6_addr_any(&np->rcv_saddr))
		saddr = &np->rcv_saddr;

	fl.proto = IPPROTO_TCP;
	ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
	ipv6_addr_copy(&fl.fl6_src,
		       (saddr ? saddr : &np->saddr));
	fl.oif = sk->sk_bound_dev_if;
	fl.fl_ip_dport = usin->sin6_port;
	fl.fl_ip_sport = inet->sport;

	if (np->opt && np->opt->srcrt) {
		struct rt0_hdr *rt0 = (struct rt0_hdr *)np->opt->srcrt;
		ipv6_addr_copy(&final, &fl.fl6_dst);
		ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
		final_p = &final;
	}

	err = ip6_dst_lookup(sk, &dst, &fl);
	if (err)
		goto failure;
	if (final_p)
		ipv6_addr_copy(&fl.fl6_dst, final_p);

	if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0) {
		dst_release(dst);
		goto failure;
	}

	if (saddr == NULL) {
		saddr = &fl.fl6_src;
		ipv6_addr_copy(&np->rcv_saddr, saddr);
	}

	/* set the source address */
	ipv6_addr_copy(&np->saddr, saddr);
	inet->rcv_saddr = LOOPBACK4_IPV6;

	ip6_dst_store(sk, dst, NULL);
	sk->sk_route_caps = dst->dev->features &
		~(NETIF_F_IP_CSUM | NETIF_F_TSO);

	tp->ext_header_len = 0;
	if (np->opt)
		tp->ext_header_len = np->opt->opt_flen + np->opt->opt_nflen;

	tp->rx_opt.mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) - sizeof(struct ipv6hdr);

	inet->dport = usin->sin6_port;

	tcp_set_state(sk, TCP_SYN_SENT);
	err = tcp_v6_hash_connect(sk);
	if (err)
		goto late_failure;

	if (!tp->write_seq)
		tp->write_seq = secure_tcpv6_sequence_number(np->saddr.s6_addr32,
							     np->daddr.s6_addr32,
							     inet->sport,
							     inet->dport);

	err = tcp_connect(sk);
	if (err)
		goto late_failure;

	return 0;

late_failure:
	tcp_set_state(sk, TCP_CLOSE);
	__sk_dst_reset(sk);
failure:
	inet->dport = 0;
	sk->sk_route_caps = 0;
	return err;
}

static void tcp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
		int type, int code, int offset, __u32 info)
{
	struct ipv6hdr *hdr = (struct ipv6hdr*)skb->data;
691
	const struct tcphdr *th = (struct tcphdr *)(skb->data+offset);
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	struct ipv6_pinfo *np;
	struct sock *sk;
	int err;
	struct tcp_sock *tp; 
	__u32 seq;

698 699
	sk = inet6_lookup(&tcp_hashinfo, &hdr->daddr, th->dest, &hdr->saddr,
			  th->source, skb->dev->ifindex);
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	if (sk == NULL) {
		ICMP6_INC_STATS_BH(__in6_dev_get(skb->dev), ICMP6_MIB_INERRORS);
		return;
	}

	if (sk->sk_state == TCP_TIME_WAIT) {
707
		inet_twsk_put((struct inet_timewait_sock *)sk);
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		return;
	}

	bh_lock_sock(sk);
	if (sock_owned_by_user(sk))
		NET_INC_STATS_BH(LINUX_MIB_LOCKDROPPEDICMPS);

	if (sk->sk_state == TCP_CLOSE)
		goto out;

	tp = tcp_sk(sk);
	seq = ntohl(th->seq); 
	if (sk->sk_state != TCP_LISTEN &&
	    !between(seq, tp->snd_una, tp->snd_nxt)) {
		NET_INC_STATS_BH(LINUX_MIB_OUTOFWINDOWICMPS);
		goto out;
	}

	np = inet6_sk(sk);

	if (type == ICMPV6_PKT_TOOBIG) {
		struct dst_entry *dst = NULL;

		if (sock_owned_by_user(sk))
			goto out;
		if ((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE))
			goto out;

		/* icmp should have updated the destination cache entry */
		dst = __sk_dst_check(sk, np->dst_cookie);

		if (dst == NULL) {
			struct inet_sock *inet = inet_sk(sk);
			struct flowi fl;

			/* BUGGG_FUTURE: Again, it is not clear how
			   to handle rthdr case. Ignore this complexity
			   for now.
			 */
			memset(&fl, 0, sizeof(fl));
			fl.proto = IPPROTO_TCP;
			ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
			ipv6_addr_copy(&fl.fl6_src, &np->saddr);
			fl.oif = sk->sk_bound_dev_if;
			fl.fl_ip_dport = inet->dport;
			fl.fl_ip_sport = inet->sport;

			if ((err = ip6_dst_lookup(sk, &dst, &fl))) {
				sk->sk_err_soft = -err;
				goto out;
			}

			if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0) {
				sk->sk_err_soft = -err;
				goto out;
			}

		} else
			dst_hold(dst);

		if (tp->pmtu_cookie > dst_mtu(dst)) {
			tcp_sync_mss(sk, dst_mtu(dst));
			tcp_simple_retransmit(sk);
		} /* else let the usual retransmit timer handle it */
		dst_release(dst);
		goto out;
	}

	icmpv6_err_convert(type, code, &err);

778
	/* Might be for an request_sock */
L
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	switch (sk->sk_state) {
780
		struct request_sock *req, **prev;
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	case TCP_LISTEN:
		if (sock_owned_by_user(sk))
			goto out;

785
		req = tcp_v6_search_req(sk, &prev, th->dest, &hdr->daddr,
786
					&hdr->saddr, inet6_iif(skb));
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		if (!req)
			goto out;

		/* ICMPs are not backlogged, hence we cannot get
		 * an established socket here.
		 */
		BUG_TRAP(req->sk == NULL);

795
		if (seq != tcp_rsk(req)->snt_isn) {
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			NET_INC_STATS_BH(LINUX_MIB_OUTOFWINDOWICMPS);
			goto out;
		}

800
		inet_csk_reqsk_queue_drop(sk, req, prev);
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		goto out;

	case TCP_SYN_SENT:
	case TCP_SYN_RECV:  /* Cannot happen.
			       It can, it SYNs are crossed. --ANK */ 
		if (!sock_owned_by_user(sk)) {
			TCP_INC_STATS_BH(TCP_MIB_ATTEMPTFAILS);
			sk->sk_err = err;
			sk->sk_error_report(sk);		/* Wake people up to see the error (see connect in sock.c) */

			tcp_done(sk);
		} else
			sk->sk_err_soft = err;
		goto out;
	}

	if (!sock_owned_by_user(sk) && np->recverr) {
		sk->sk_err = err;
		sk->sk_error_report(sk);
	} else
		sk->sk_err_soft = err;

out:
	bh_unlock_sock(sk);
	sock_put(sk);
}


829
static int tcp_v6_send_synack(struct sock *sk, struct request_sock *req,
L
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			      struct dst_entry *dst)
{
832
	struct tcp6_request_sock *treq = tcp6_rsk(req);
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	struct ipv6_pinfo *np = inet6_sk(sk);
	struct sk_buff * skb;
	struct ipv6_txoptions *opt = NULL;
	struct in6_addr * final_p = NULL, final;
	struct flowi fl;
	int err = -1;

	memset(&fl, 0, sizeof(fl));
	fl.proto = IPPROTO_TCP;
842 843
	ipv6_addr_copy(&fl.fl6_dst, &treq->rmt_addr);
	ipv6_addr_copy(&fl.fl6_src, &treq->loc_addr);
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	fl.fl6_flowlabel = 0;
845 846
	fl.oif = treq->iif;
	fl.fl_ip_dport = inet_rsk(req)->rmt_port;
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	fl.fl_ip_sport = inet_sk(sk)->sport;

	if (dst == NULL) {
		opt = np->opt;
		if (opt == NULL &&
		    np->rxopt.bits.srcrt == 2 &&
853 854
		    treq->pktopts) {
			struct sk_buff *pktopts = treq->pktopts;
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			struct inet6_skb_parm *rxopt = IP6CB(pktopts);
			if (rxopt->srcrt)
				opt = ipv6_invert_rthdr(sk, (struct ipv6_rt_hdr*)(pktopts->nh.raw + rxopt->srcrt));
		}

		if (opt && opt->srcrt) {
			struct rt0_hdr *rt0 = (struct rt0_hdr *) opt->srcrt;
			ipv6_addr_copy(&final, &fl.fl6_dst);
			ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
			final_p = &final;
		}

		err = ip6_dst_lookup(sk, &dst, &fl);
		if (err)
			goto done;
		if (final_p)
			ipv6_addr_copy(&fl.fl6_dst, final_p);
		if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0)
			goto done;
	}

	skb = tcp_make_synack(sk, dst, req);
	if (skb) {
		struct tcphdr *th = skb->h.th;

		th->check = tcp_v6_check(th, skb->len,
881
					 &treq->loc_addr, &treq->rmt_addr,
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					 csum_partial((char *)th, skb->len, skb->csum));

884
		ipv6_addr_copy(&fl.fl6_dst, &treq->rmt_addr);
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		err = ip6_xmit(sk, skb, &fl, opt, 0);
		if (err == NET_XMIT_CN)
			err = 0;
	}

done:
	dst_release(dst);
        if (opt && opt != np->opt)
		sock_kfree_s(sk, opt, opt->tot_len);
	return err;
}

897
static void tcp_v6_reqsk_destructor(struct request_sock *req)
L
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{
899 900
	if (tcp6_rsk(req)->pktopts)
		kfree_skb(tcp6_rsk(req)->pktopts);
L
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}

903
static struct request_sock_ops tcp6_request_sock_ops = {
L
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	.family		=	AF_INET6,
905
	.obj_size	=	sizeof(struct tcp6_request_sock),
L
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	.rtx_syn_ack	=	tcp_v6_send_synack,
907 908
	.send_ack	=	tcp_v6_reqsk_send_ack,
	.destructor	=	tcp_v6_reqsk_destructor,
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	.send_reset	=	tcp_v6_send_reset
};

static int ipv6_opt_accepted(struct sock *sk, struct sk_buff *skb)
{
	struct ipv6_pinfo *np = inet6_sk(sk);
	struct inet6_skb_parm *opt = IP6CB(skb);

	if (np->rxopt.all) {
		if ((opt->hop && np->rxopt.bits.hopopts) ||
		    ((IPV6_FLOWINFO_MASK&*(u32*)skb->nh.raw) &&
		     np->rxopt.bits.rxflow) ||
		    (opt->srcrt && np->rxopt.bits.srcrt) ||
		    ((opt->dst1 || opt->dst0) && np->rxopt.bits.dstopts))
			return 1;
	}
	return 0;
}


static void tcp_v6_send_check(struct sock *sk, struct tcphdr *th, int len, 
			      struct sk_buff *skb)
{
	struct ipv6_pinfo *np = inet6_sk(sk);

	if (skb->ip_summed == CHECKSUM_HW) {
		th->check = ~csum_ipv6_magic(&np->saddr, &np->daddr, len, IPPROTO_TCP,  0);
		skb->csum = offsetof(struct tcphdr, check);
	} else {
		th->check = csum_ipv6_magic(&np->saddr, &np->daddr, len, IPPROTO_TCP, 
					    csum_partial((char *)th, th->doff<<2, 
							 skb->csum));
	}
}


static void tcp_v6_send_reset(struct sk_buff *skb)
{
	struct tcphdr *th = skb->h.th, *t1; 
	struct sk_buff *buff;
	struct flowi fl;

	if (th->rst)
		return;

	if (!ipv6_unicast_destination(skb))
		return; 

	/*
	 * We need to grab some memory, and put together an RST,
	 * and then put it into the queue to be sent.
	 */

	buff = alloc_skb(MAX_HEADER + sizeof(struct ipv6hdr) + sizeof(struct tcphdr),
			 GFP_ATOMIC);
	if (buff == NULL) 
	  	return;

	skb_reserve(buff, MAX_HEADER + sizeof(struct ipv6hdr) + sizeof(struct tcphdr));

	t1 = (struct tcphdr *) skb_push(buff,sizeof(struct tcphdr));

	/* Swap the send and the receive. */
	memset(t1, 0, sizeof(*t1));
	t1->dest = th->source;
	t1->source = th->dest;
	t1->doff = sizeof(*t1)/4;
	t1->rst = 1;
  
	if(th->ack) {
	  	t1->seq = th->ack_seq;
	} else {
		t1->ack = 1;
		t1->ack_seq = htonl(ntohl(th->seq) + th->syn + th->fin
				    + skb->len - (th->doff<<2));
	}

	buff->csum = csum_partial((char *)t1, sizeof(*t1), 0);

	memset(&fl, 0, sizeof(fl));
	ipv6_addr_copy(&fl.fl6_dst, &skb->nh.ipv6h->saddr);
	ipv6_addr_copy(&fl.fl6_src, &skb->nh.ipv6h->daddr);

	t1->check = csum_ipv6_magic(&fl.fl6_src, &fl.fl6_dst,
				    sizeof(*t1), IPPROTO_TCP,
				    buff->csum);

	fl.proto = IPPROTO_TCP;
997
	fl.oif = inet6_iif(skb);
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	fl.fl_ip_dport = t1->dest;
	fl.fl_ip_sport = t1->source;

	/* sk = NULL, but it is safe for now. RST socket required. */
	if (!ip6_dst_lookup(NULL, &buff->dst, &fl)) {

		if ((xfrm_lookup(&buff->dst, &fl, NULL, 0)) < 0) {
			dst_release(buff->dst);
			return;
		}

		ip6_xmit(NULL, buff, &fl, NULL, 0);
		TCP_INC_STATS_BH(TCP_MIB_OUTSEGS);
		TCP_INC_STATS_BH(TCP_MIB_OUTRSTS);
		return;
	}

	kfree_skb(buff);
}

static void tcp_v6_send_ack(struct sk_buff *skb, u32 seq, u32 ack, u32 win, u32 ts)
{
	struct tcphdr *th = skb->h.th, *t1;
	struct sk_buff *buff;
	struct flowi fl;
	int tot_len = sizeof(struct tcphdr);

	if (ts)
		tot_len += 3*4;

	buff = alloc_skb(MAX_HEADER + sizeof(struct ipv6hdr) + tot_len,
			 GFP_ATOMIC);
	if (buff == NULL)
		return;

	skb_reserve(buff, MAX_HEADER + sizeof(struct ipv6hdr) + tot_len);

	t1 = (struct tcphdr *) skb_push(buff,tot_len);

	/* Swap the send and the receive. */
	memset(t1, 0, sizeof(*t1));
	t1->dest = th->source;
	t1->source = th->dest;
	t1->doff = tot_len/4;
	t1->seq = htonl(seq);
	t1->ack_seq = htonl(ack);
	t1->ack = 1;
	t1->window = htons(win);
	
	if (ts) {
		u32 *ptr = (u32*)(t1 + 1);
		*ptr++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) |
			       (TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP);
		*ptr++ = htonl(tcp_time_stamp);
		*ptr = htonl(ts);
	}

	buff->csum = csum_partial((char *)t1, tot_len, 0);

	memset(&fl, 0, sizeof(fl));
	ipv6_addr_copy(&fl.fl6_dst, &skb->nh.ipv6h->saddr);
	ipv6_addr_copy(&fl.fl6_src, &skb->nh.ipv6h->daddr);

	t1->check = csum_ipv6_magic(&fl.fl6_src, &fl.fl6_dst,
				    tot_len, IPPROTO_TCP,
				    buff->csum);

	fl.proto = IPPROTO_TCP;
1066
	fl.oif = inet6_iif(skb);
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	fl.fl_ip_dport = t1->dest;
	fl.fl_ip_sport = t1->source;

	if (!ip6_dst_lookup(NULL, &buff->dst, &fl)) {
		if ((xfrm_lookup(&buff->dst, &fl, NULL, 0)) < 0) {
			dst_release(buff->dst);
			return;
		}
		ip6_xmit(NULL, buff, &fl, NULL, 0);
		TCP_INC_STATS_BH(TCP_MIB_OUTSEGS);
		return;
	}

	kfree_skb(buff);
}

static void tcp_v6_timewait_ack(struct sock *sk, struct sk_buff *skb)
{
1085 1086
	struct inet_timewait_sock *tw = inet_twsk(sk);
	const struct tcp_timewait_sock *tcptw = tcp_twsk(sk);
L
Linus Torvalds 已提交
1087

1088 1089 1090
	tcp_v6_send_ack(skb, tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt,
			tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale,
			tcptw->tw_ts_recent);
L
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1091

1092
	inet_twsk_put(tw);
L
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1093 1094
}

1095
static void tcp_v6_reqsk_send_ack(struct sk_buff *skb, struct request_sock *req)
L
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1096
{
1097
	tcp_v6_send_ack(skb, tcp_rsk(req)->snt_isn + 1, tcp_rsk(req)->rcv_isn + 1, req->rcv_wnd, req->ts_recent);
L
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1098 1099 1100 1101 1102
}


static struct sock *tcp_v6_hnd_req(struct sock *sk,struct sk_buff *skb)
{
1103
	struct request_sock *req, **prev;
1104
	const struct tcphdr *th = skb->h.th;
L
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1105 1106 1107
	struct sock *nsk;

	/* Find possible connection requests. */
1108
	req = tcp_v6_search_req(sk, &prev, th->source, &skb->nh.ipv6h->saddr,
1109
				&skb->nh.ipv6h->daddr, inet6_iif(skb));
L
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1110 1111 1112
	if (req)
		return tcp_check_req(sk, skb, req, prev);

1113 1114 1115
	nsk = __inet6_lookup_established(&tcp_hashinfo, &skb->nh.ipv6h->saddr,
					 th->source, &skb->nh.ipv6h->daddr,
					 ntohs(th->dest), inet6_iif(skb));
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	if (nsk) {
		if (nsk->sk_state != TCP_TIME_WAIT) {
			bh_lock_sock(nsk);
			return nsk;
		}
1122
		inet_twsk_put((struct inet_timewait_sock *)nsk);
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		return NULL;
	}

#if 0 /*def CONFIG_SYN_COOKIES*/
	if (!th->rst && !th->syn && th->ack)
		sk = cookie_v6_check(sk, skb, &(IPCB(skb)->opt));
#endif
	return sk;
}

1133
static void tcp_v6_synq_add(struct sock *sk, struct request_sock *req)
L
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{
1135 1136 1137
	struct inet_connection_sock *icsk = inet_csk(sk);
	struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt;
	const u32 h = tcp_v6_synq_hash(&tcp6_rsk(req)->rmt_addr, inet_rsk(req)->rmt_port, lopt->hash_rnd);
L
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1139 1140
	reqsk_queue_hash_req(&icsk->icsk_accept_queue, h, req, TCP_TIMEOUT_INIT);
	inet_csk_reqsk_queue_added(sk, TCP_TIMEOUT_INIT);
L
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}


/* 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)
{
1149
	struct tcp6_request_sock *treq;
L
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	struct ipv6_pinfo *np = inet6_sk(sk);
	struct tcp_options_received tmp_opt;
	struct tcp_sock *tp = tcp_sk(sk);
1153
	struct request_sock *req = NULL;
L
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	__u32 isn = TCP_SKB_CB(skb)->when;

	if (skb->protocol == htons(ETH_P_IP))
		return tcp_v4_conn_request(sk, skb);

	if (!ipv6_unicast_destination(skb))
		goto drop; 

	/*
	 *	There are no SYN attacks on IPv6, yet...	
	 */
1165
	if (inet_csk_reqsk_queue_is_full(sk) && !isn) {
L
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		if (net_ratelimit())
			printk(KERN_INFO "TCPv6: dropping request, synflood is possible\n");
		goto drop;		
	}

1171
	if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1)
L
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		goto drop;

1174
	req = reqsk_alloc(&tcp6_request_sock_ops);
L
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	if (req == NULL)
		goto drop;

	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);

	tmp_opt.tstamp_ok = tmp_opt.saw_tstamp;
	tcp_openreq_init(req, &tmp_opt, skb);

1187 1188 1189
	treq = tcp6_rsk(req);
	ipv6_addr_copy(&treq->rmt_addr, &skb->nh.ipv6h->saddr);
	ipv6_addr_copy(&treq->loc_addr, &skb->nh.ipv6h->daddr);
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	TCP_ECN_create_request(req, skb->h.th);
1191
	treq->pktopts = NULL;
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	if (ipv6_opt_accepted(sk, skb) ||
	    np->rxopt.bits.rxinfo ||
	    np->rxopt.bits.rxhlim) {
		atomic_inc(&skb->users);
1196
		treq->pktopts = skb;
L
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	}
1198
	treq->iif = sk->sk_bound_dev_if;
L
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	/* So that link locals have meaning */
	if (!sk->sk_bound_dev_if &&
1202
	    ipv6_addr_type(&treq->rmt_addr) & IPV6_ADDR_LINKLOCAL)
1203
		treq->iif = inet6_iif(skb);
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	if (isn == 0) 
		isn = tcp_v6_init_sequence(sk,skb);

1208
	tcp_rsk(req)->snt_isn = isn;
L
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	if (tcp_v6_send_synack(sk, req, NULL))
		goto drop;

	tcp_v6_synq_add(sk, req);

	return 0;

drop:
	if (req)
1219
		reqsk_free(req);
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	TCP_INC_STATS_BH(TCP_MIB_ATTEMPTFAILS);
	return 0; /* don't send reset */
}

static struct sock * tcp_v6_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
1226
					  struct request_sock *req,
L
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					  struct dst_entry *dst)
{
1229
	struct tcp6_request_sock *treq = tcp6_rsk(req);
L
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	struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
	struct tcp6_sock *newtcp6sk;
	struct inet_sock *newinet;
	struct tcp_sock *newtp;
	struct sock *newsk;
	struct ipv6_txoptions *opt;

	if (skb->protocol == htons(ETH_P_IP)) {
		/*
		 *	v6 mapped
		 */

		newsk = tcp_v4_syn_recv_sock(sk, skb, req, dst);

		if (newsk == NULL) 
			return NULL;

		newtcp6sk = (struct tcp6_sock *)newsk;
		inet_sk(newsk)->pinet6 = &newtcp6sk->inet6;

		newinet = inet_sk(newsk);
		newnp = inet6_sk(newsk);
		newtp = tcp_sk(newsk);

		memcpy(newnp, np, sizeof(struct ipv6_pinfo));

		ipv6_addr_set(&newnp->daddr, 0, 0, htonl(0x0000FFFF),
			      newinet->daddr);

		ipv6_addr_set(&newnp->saddr, 0, 0, htonl(0x0000FFFF),
			      newinet->saddr);

		ipv6_addr_copy(&newnp->rcv_saddr, &newnp->saddr);

		newtp->af_specific = &ipv6_mapped;
		newsk->sk_backlog_rcv = tcp_v4_do_rcv;
		newnp->pktoptions  = NULL;
		newnp->opt	   = NULL;
1268
		newnp->mcast_oif   = inet6_iif(skb);
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		newnp->mcast_hops  = skb->nh.ipv6h->hop_limit;

1271 1272 1273 1274
		/*
		 * No need to charge this sock to the relevant IPv6 refcnt debug socks count
		 * here, tcp_create_openreq_child now does this for us, see the comment in
		 * that function for the gory details. -acme
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		 */

		/* It is tricky place. Until this moment IPv4 tcp
		   worked with IPv6 af_tcp.af_specific.
		   Sync it now.
		 */
		tcp_sync_mss(newsk, newtp->pmtu_cookie);

		return newsk;
	}

	opt = np->opt;

	if (sk_acceptq_is_full(sk))
		goto out_overflow;

	if (np->rxopt.bits.srcrt == 2 &&
1292 1293
	    opt == NULL && treq->pktopts) {
		struct inet6_skb_parm *rxopt = IP6CB(treq->pktopts);
L
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		if (rxopt->srcrt)
1295
			opt = ipv6_invert_rthdr(sk, (struct ipv6_rt_hdr *)(treq->pktopts->nh.raw + rxopt->srcrt));
L
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	}

	if (dst == NULL) {
		struct in6_addr *final_p = NULL, final;
		struct flowi fl;

		memset(&fl, 0, sizeof(fl));
		fl.proto = IPPROTO_TCP;
1304
		ipv6_addr_copy(&fl.fl6_dst, &treq->rmt_addr);
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		if (opt && opt->srcrt) {
			struct rt0_hdr *rt0 = (struct rt0_hdr *) opt->srcrt;
			ipv6_addr_copy(&final, &fl.fl6_dst);
			ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
			final_p = &final;
		}
1311
		ipv6_addr_copy(&fl.fl6_src, &treq->loc_addr);
L
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		fl.oif = sk->sk_bound_dev_if;
1313
		fl.fl_ip_dport = inet_rsk(req)->rmt_port;
L
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		fl.fl_ip_sport = inet_sk(sk)->sport;

		if (ip6_dst_lookup(sk, &dst, &fl))
			goto out;

		if (final_p)
			ipv6_addr_copy(&fl.fl6_dst, final_p);

		if ((xfrm_lookup(&dst, &fl, sk, 0)) < 0)
			goto out;
	} 

	newsk = tcp_create_openreq_child(sk, req, skb);
	if (newsk == NULL)
		goto out;

1330 1331 1332 1333 1334
	/*
	 * No need to charge this sock to the relevant IPv6 refcnt debug socks
	 * count here, tcp_create_openreq_child now does this for us, see the
	 * comment in that function for the gory details. -acme
	 */
L
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	ip6_dst_store(newsk, dst, NULL);
	newsk->sk_route_caps = dst->dev->features &
		~(NETIF_F_IP_CSUM | NETIF_F_TSO);

	newtcp6sk = (struct tcp6_sock *)newsk;
	inet_sk(newsk)->pinet6 = &newtcp6sk->inet6;

	newtp = tcp_sk(newsk);
	newinet = inet_sk(newsk);
	newnp = inet6_sk(newsk);

	memcpy(newnp, np, sizeof(struct ipv6_pinfo));

1349 1350 1351 1352
	ipv6_addr_copy(&newnp->daddr, &treq->rmt_addr);
	ipv6_addr_copy(&newnp->saddr, &treq->loc_addr);
	ipv6_addr_copy(&newnp->rcv_saddr, &treq->loc_addr);
	newsk->sk_bound_dev_if = treq->iif;
L
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	/* Now IPv6 options... 

	   First: no IPv4 options.
	 */
	newinet->opt = NULL;

	/* Clone RX bits */
	newnp->rxopt.all = np->rxopt.all;

	/* Clone pktoptions received with SYN */
	newnp->pktoptions = NULL;
1365 1366 1367 1368
	if (treq->pktopts != NULL) {
		newnp->pktoptions = skb_clone(treq->pktopts, GFP_ATOMIC);
		kfree_skb(treq->pktopts);
		treq->pktopts = NULL;
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		if (newnp->pktoptions)
			skb_set_owner_r(newnp->pktoptions, newsk);
	}
	newnp->opt	  = NULL;
1373
	newnp->mcast_oif  = inet6_iif(skb);
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	newnp->mcast_hops = skb->nh.ipv6h->hop_limit;

	/* Clone native IPv6 options from listening socket (if any)

	   Yes, keeping reference count would be much more clever,
	   but we make one more one thing there: reattach optmem
	   to newsk.
	 */
	if (opt) {
		newnp->opt = ipv6_dup_options(newsk, opt);
		if (opt != np->opt)
			sock_kfree_s(sk, opt, opt->tot_len);
	}

	newtp->ext_header_len = 0;
	if (newnp->opt)
		newtp->ext_header_len = newnp->opt->opt_nflen +
					newnp->opt->opt_flen;

	tcp_sync_mss(newsk, dst_mtu(dst));
	newtp->advmss = dst_metric(dst, RTAX_ADVMSS);
	tcp_initialize_rcv_mss(newsk);

	newinet->daddr = newinet->saddr = newinet->rcv_saddr = LOOPBACK4_IPV6;

	__tcp_v6_hash(newsk);
1400
	inet_inherit_port(&tcp_hashinfo, sk, newsk);
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	return newsk;

out_overflow:
	NET_INC_STATS_BH(LINUX_MIB_LISTENOVERFLOWS);
out:
	NET_INC_STATS_BH(LINUX_MIB_LISTENDROPS);
	if (opt && opt != np->opt)
		sock_kfree_s(sk, opt, opt->tot_len);
	dst_release(dst);
	return NULL;
}

static int tcp_v6_checksum_init(struct sk_buff *skb)
{
	if (skb->ip_summed == CHECKSUM_HW) {
		skb->ip_summed = CHECKSUM_UNNECESSARY;
		if (!tcp_v6_check(skb->h.th,skb->len,&skb->nh.ipv6h->saddr,
				  &skb->nh.ipv6h->daddr,skb->csum))
			return 0;
1421
		LIMIT_NETDEBUG(KERN_DEBUG "hw tcp v6 csum failed\n");
L
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1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547
	}
	if (skb->len <= 76) {
		if (tcp_v6_check(skb->h.th,skb->len,&skb->nh.ipv6h->saddr,
				 &skb->nh.ipv6h->daddr,skb_checksum(skb, 0, skb->len, 0)))
			return -1;
		skb->ip_summed = CHECKSUM_UNNECESSARY;
	} else {
		skb->csum = ~tcp_v6_check(skb->h.th,skb->len,&skb->nh.ipv6h->saddr,
					  &skb->nh.ipv6h->daddr,0);
	}
	return 0;
}

/* The socket must have it's spinlock held when we get
 * here.
 *
 * We have a potential double-lock case here, so even when
 * doing backlog processing we use the BH locking scheme.
 * This is because we cannot sleep with the original spinlock
 * held.
 */
static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
{
	struct ipv6_pinfo *np = inet6_sk(sk);
	struct tcp_sock *tp;
	struct sk_buff *opt_skb = NULL;

	/* Imagine: socket is IPv6. IPv4 packet arrives,
	   goes to IPv4 receive handler and backlogged.
	   From backlog it always goes here. Kerboom...
	   Fortunately, tcp_rcv_established and rcv_established
	   handle them correctly, but it is not case with
	   tcp_v6_hnd_req and tcp_v6_send_reset().   --ANK
	 */

	if (skb->protocol == htons(ETH_P_IP))
		return tcp_v4_do_rcv(sk, skb);

	if (sk_filter(sk, skb, 0))
		goto discard;

	/*
	 *	socket locking is here for SMP purposes as backlog rcv
	 *	is currently called with bh processing disabled.
	 */

	/* Do Stevens' IPV6_PKTOPTIONS.

	   Yes, guys, it is the only place in our code, where we
	   may make it not affecting IPv4.
	   The rest of code is protocol independent,
	   and I do not like idea to uglify IPv4.

	   Actually, all the idea behind IPV6_PKTOPTIONS
	   looks not very well thought. For now we latch
	   options, received in the last packet, enqueued
	   by tcp. Feel free to propose better solution.
	                                       --ANK (980728)
	 */
	if (np->rxopt.all)
		opt_skb = skb_clone(skb, GFP_ATOMIC);

	if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */
		TCP_CHECK_TIMER(sk);
		if (tcp_rcv_established(sk, skb, skb->h.th, skb->len))
			goto reset;
		TCP_CHECK_TIMER(sk);
		if (opt_skb)
			goto ipv6_pktoptions;
		return 0;
	}

	if (skb->len < (skb->h.th->doff<<2) || tcp_checksum_complete(skb))
		goto csum_err;

	if (sk->sk_state == TCP_LISTEN) { 
		struct sock *nsk = tcp_v6_hnd_req(sk, skb);
		if (!nsk)
			goto discard;

		/*
		 * Queue it on the new socket if the new socket is active,
		 * otherwise we just shortcircuit this and continue with
		 * the new socket..
		 */
 		if(nsk != sk) {
			if (tcp_child_process(sk, nsk, skb))
				goto reset;
			if (opt_skb)
				__kfree_skb(opt_skb);
			return 0;
		}
	}

	TCP_CHECK_TIMER(sk);
	if (tcp_rcv_state_process(sk, skb, skb->h.th, skb->len))
		goto reset;
	TCP_CHECK_TIMER(sk);
	if (opt_skb)
		goto ipv6_pktoptions;
	return 0;

reset:
	tcp_v6_send_reset(skb);
discard:
	if (opt_skb)
		__kfree_skb(opt_skb);
	kfree_skb(skb);
	return 0;
csum_err:
	TCP_INC_STATS_BH(TCP_MIB_INERRS);
	goto discard;


ipv6_pktoptions:
	/* Do you ask, what is it?

	   1. skb was enqueued by tcp.
	   2. skb is added to tail of read queue, rather than out of order.
	   3. socket is not in passive state.
	   4. Finally, it really contains options, which user wants to receive.
	 */
	tp = tcp_sk(sk);
	if (TCP_SKB_CB(opt_skb)->end_seq == tp->rcv_nxt &&
	    !((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN))) {
		if (np->rxopt.bits.rxinfo)
1548
			np->mcast_oif = inet6_iif(opt_skb);
L
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1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602
		if (np->rxopt.bits.rxhlim)
			np->mcast_hops = opt_skb->nh.ipv6h->hop_limit;
		if (ipv6_opt_accepted(sk, opt_skb)) {
			skb_set_owner_r(opt_skb, sk);
			opt_skb = xchg(&np->pktoptions, opt_skb);
		} else {
			__kfree_skb(opt_skb);
			opt_skb = xchg(&np->pktoptions, NULL);
		}
	}

	if (opt_skb)
		kfree_skb(opt_skb);
	return 0;
}

static int tcp_v6_rcv(struct sk_buff **pskb, unsigned int *nhoffp)
{
	struct sk_buff *skb = *pskb;
	struct tcphdr *th;	
	struct sock *sk;
	int ret;

	if (skb->pkt_type != PACKET_HOST)
		goto discard_it;

	/*
	 *	Count it even if it's bad.
	 */
	TCP_INC_STATS_BH(TCP_MIB_INSEGS);

	if (!pskb_may_pull(skb, sizeof(struct tcphdr)))
		goto discard_it;

	th = skb->h.th;

	if (th->doff < sizeof(struct tcphdr)/4)
		goto bad_packet;
	if (!pskb_may_pull(skb, th->doff*4))
		goto discard_it;

	if ((skb->ip_summed != CHECKSUM_UNNECESSARY &&
	     tcp_v6_checksum_init(skb) < 0))
		goto bad_packet;

	th = skb->h.th;
	TCP_SKB_CB(skb)->seq = ntohl(th->seq);
	TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin +
				    skb->len - th->doff*4);
	TCP_SKB_CB(skb)->ack_seq = ntohl(th->ack_seq);
	TCP_SKB_CB(skb)->when = 0;
	TCP_SKB_CB(skb)->flags = ipv6_get_dsfield(skb->nh.ipv6h);
	TCP_SKB_CB(skb)->sacked = 0;

1603 1604 1605
	sk = __inet6_lookup(&tcp_hashinfo, &skb->nh.ipv6h->saddr, th->source,
			    &skb->nh.ipv6h->daddr, ntohs(th->dest),
			    inet6_iif(skb));
L
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1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659

	if (!sk)
		goto no_tcp_socket;

process:
	if (sk->sk_state == TCP_TIME_WAIT)
		goto do_time_wait;

	if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb))
		goto discard_and_relse;

	if (sk_filter(sk, skb, 0))
		goto discard_and_relse;

	skb->dev = NULL;

	bh_lock_sock(sk);
	ret = 0;
	if (!sock_owned_by_user(sk)) {
		if (!tcp_prequeue(sk, skb))
			ret = tcp_v6_do_rcv(sk, skb);
	} else
		sk_add_backlog(sk, skb);
	bh_unlock_sock(sk);

	sock_put(sk);
	return ret ? -1 : 0;

no_tcp_socket:
	if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
		goto discard_it;

	if (skb->len < (th->doff<<2) || tcp_checksum_complete(skb)) {
bad_packet:
		TCP_INC_STATS_BH(TCP_MIB_INERRS);
	} else {
		tcp_v6_send_reset(skb);
	}

discard_it:

	/*
	 *	Discard frame
	 */

	kfree_skb(skb);
	return 0;

discard_and_relse:
	sock_put(sk);
	goto discard_it;

do_time_wait:
	if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
1660
		inet_twsk_put((struct inet_timewait_sock *)sk);
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		goto discard_it;
	}

	if (skb->len < (th->doff<<2) || tcp_checksum_complete(skb)) {
		TCP_INC_STATS_BH(TCP_MIB_INERRS);
1666
		inet_twsk_put((struct inet_timewait_sock *)sk);
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		goto discard_it;
	}

1670 1671
	switch (tcp_timewait_state_process((struct inet_timewait_sock *)sk,
					   skb, th)) {
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	case TCP_TW_SYN:
	{
		struct sock *sk2;

1676 1677 1678
		sk2 = inet6_lookup_listener(&tcp_hashinfo,
					    &skb->nh.ipv6h->daddr,
					    ntohs(th->dest), inet6_iif(skb));
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		if (sk2 != NULL) {
1680 1681 1682
			struct inet_timewait_sock *tw = inet_twsk(sk);
			inet_twsk_deschedule(tw, &tcp_death_row);
			inet_twsk_put(tw);
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			sk = sk2;
			goto process;
		}
		/* Fall through to ACK */
	}
	case TCP_TW_ACK:
		tcp_v6_timewait_ack(sk, skb);
		break;
	case TCP_TW_RST:
		goto no_tcp_socket;
	case TCP_TW_SUCCESS:;
	}
	goto discard_it;
}

static int tcp_v6_rebuild_header(struct sock *sk)
{
	int err;
	struct dst_entry *dst;
	struct ipv6_pinfo *np = inet6_sk(sk);

	dst = __sk_dst_check(sk, np->dst_cookie);

	if (dst == NULL) {
		struct inet_sock *inet = inet_sk(sk);
		struct in6_addr *final_p = NULL, final;
		struct flowi fl;

		memset(&fl, 0, sizeof(fl));
		fl.proto = IPPROTO_TCP;
		ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
		ipv6_addr_copy(&fl.fl6_src, &np->saddr);
		fl.fl6_flowlabel = np->flow_label;
		fl.oif = sk->sk_bound_dev_if;
		fl.fl_ip_dport = inet->dport;
		fl.fl_ip_sport = inet->sport;

		if (np->opt && np->opt->srcrt) {
			struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt;
			ipv6_addr_copy(&final, &fl.fl6_dst);
			ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
			final_p = &final;
		}

		err = ip6_dst_lookup(sk, &dst, &fl);
		if (err) {
			sk->sk_route_caps = 0;
			return err;
		}
		if (final_p)
			ipv6_addr_copy(&fl.fl6_dst, final_p);

		if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0) {
			sk->sk_err_soft = -err;
			dst_release(dst);
			return err;
		}

		ip6_dst_store(sk, dst, NULL);
		sk->sk_route_caps = dst->dev->features &
			~(NETIF_F_IP_CSUM | NETIF_F_TSO);
	}

	return 0;
}

static int tcp_v6_xmit(struct sk_buff *skb, int ipfragok)
{
	struct sock *sk = skb->sk;
	struct inet_sock *inet = inet_sk(sk);
	struct ipv6_pinfo *np = inet6_sk(sk);
	struct flowi fl;
	struct dst_entry *dst;
	struct in6_addr *final_p = NULL, final;

	memset(&fl, 0, sizeof(fl));
	fl.proto = IPPROTO_TCP;
	ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
	ipv6_addr_copy(&fl.fl6_src, &np->saddr);
	fl.fl6_flowlabel = np->flow_label;
	IP6_ECN_flow_xmit(sk, fl.fl6_flowlabel);
	fl.oif = sk->sk_bound_dev_if;
	fl.fl_ip_sport = inet->sport;
	fl.fl_ip_dport = inet->dport;

	if (np->opt && np->opt->srcrt) {
		struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt;
		ipv6_addr_copy(&final, &fl.fl6_dst);
		ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
		final_p = &final;
	}

	dst = __sk_dst_check(sk, np->dst_cookie);

	if (dst == NULL) {
		int err = ip6_dst_lookup(sk, &dst, &fl);

		if (err) {
			sk->sk_err_soft = -err;
			return err;
		}

		if (final_p)
			ipv6_addr_copy(&fl.fl6_dst, final_p);

		if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0) {
			sk->sk_route_caps = 0;
			dst_release(dst);
			return err;
		}

		ip6_dst_store(sk, dst, NULL);
		sk->sk_route_caps = dst->dev->features &
			~(NETIF_F_IP_CSUM | NETIF_F_TSO);
	}

	skb->dst = dst_clone(dst);

	/* Restore final destination back after routing done */
	ipv6_addr_copy(&fl.fl6_dst, &np->daddr);

	return ip6_xmit(sk, skb, &fl, np->opt, 0);
}

static void v6_addr2sockaddr(struct sock *sk, struct sockaddr * uaddr)
{
	struct ipv6_pinfo *np = inet6_sk(sk);
	struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) uaddr;

	sin6->sin6_family = AF_INET6;
	ipv6_addr_copy(&sin6->sin6_addr, &np->daddr);
	sin6->sin6_port	= inet_sk(sk)->dport;
	/* We do not store received flowlabel for TCP */
	sin6->sin6_flowinfo = 0;
	sin6->sin6_scope_id = 0;
	if (sk->sk_bound_dev_if &&
	    ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
		sin6->sin6_scope_id = sk->sk_bound_dev_if;
}

static int tcp_v6_remember_stamp(struct sock *sk)
{
	/* Alas, not yet... */
	return 0;
}

static struct tcp_func ipv6_specific = {
	.queue_xmit	=	tcp_v6_xmit,
	.send_check	=	tcp_v6_send_check,
	.rebuild_header	=	tcp_v6_rebuild_header,
	.conn_request	=	tcp_v6_conn_request,
	.syn_recv_sock	=	tcp_v6_syn_recv_sock,
	.remember_stamp	=	tcp_v6_remember_stamp,
	.net_header_len	=	sizeof(struct ipv6hdr),

	.setsockopt	=	ipv6_setsockopt,
	.getsockopt	=	ipv6_getsockopt,
	.addr2sockaddr	=	v6_addr2sockaddr,
	.sockaddr_len	=	sizeof(struct sockaddr_in6)
};

/*
 *	TCP over IPv4 via INET6 API
 */

static struct tcp_func ipv6_mapped = {
	.queue_xmit	=	ip_queue_xmit,
	.send_check	=	tcp_v4_send_check,
1851
	.rebuild_header	=	inet_sk_rebuild_header,
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	.conn_request	=	tcp_v6_conn_request,
	.syn_recv_sock	=	tcp_v6_syn_recv_sock,
	.remember_stamp	=	tcp_v4_remember_stamp,
	.net_header_len	=	sizeof(struct iphdr),

	.setsockopt	=	ipv6_setsockopt,
	.getsockopt	=	ipv6_getsockopt,
	.addr2sockaddr	=	v6_addr2sockaddr,
	.sockaddr_len	=	sizeof(struct sockaddr_in6)
};



/* NOTE: A lot of things set to zero explicitly by call to
 *       sk_alloc() so need not be done here.
 */
static int tcp_v6_init_sock(struct sock *sk)
{
1870
	struct inet_connection_sock *icsk = inet_csk(sk);
L
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	struct tcp_sock *tp = tcp_sk(sk);

	skb_queue_head_init(&tp->out_of_order_queue);
	tcp_init_xmit_timers(sk);
	tcp_prequeue_init(tp);

1877
	icsk->icsk_rto = TCP_TIMEOUT_INIT;
L
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	tp->mdev = TCP_TIMEOUT_INIT;

	/* So many TCP implementations out there (incorrectly) count the
	 * initial SYN frame in their delayed-ACK and congestion control
	 * algorithms that we must have the following bandaid to talk
	 * efficiently to them.  -DaveM
	 */
	tp->snd_cwnd = 2;

	/* See draft-stevens-tcpca-spec-01 for discussion of the
	 * initialization of these values.
	 */
	tp->snd_ssthresh = 0x7fffffff;
	tp->snd_cwnd_clamp = ~0;
1892
	tp->mss_cache = 536;
L
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	tp->reordering = sysctl_tcp_reordering;

	sk->sk_state = TCP_CLOSE;

	tp->af_specific = &ipv6_specific;
1899
	icsk->icsk_ca_ops = &tcp_init_congestion_ops;
L
Linus Torvalds 已提交
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	sk->sk_write_space = sk_stream_write_space;
	sock_set_flag(sk, SOCK_USE_WRITE_QUEUE);

	sk->sk_sndbuf = sysctl_tcp_wmem[1];
	sk->sk_rcvbuf = sysctl_tcp_rmem[1];

	atomic_inc(&tcp_sockets_allocated);

	return 0;
}

static int tcp_v6_destroy_sock(struct sock *sk)
{
	tcp_v4_destroy_sock(sk);
	return inet6_destroy_sock(sk);
}

/* Proc filesystem TCPv6 sock list dumping. */
static void get_openreq6(struct seq_file *seq, 
1919
			 struct sock *sk, struct request_sock *req, int i, int uid)
L
Linus Torvalds 已提交
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{
	struct in6_addr *dest, *src;
	int ttd = req->expires - jiffies;

	if (ttd < 0)
		ttd = 0;

1927 1928
	src = &tcp6_rsk(req)->loc_addr;
	dest = &tcp6_rsk(req)->rmt_addr;
L
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1929 1930 1931 1932 1933 1934 1935 1936 1937
	seq_printf(seq,
		   "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
		   "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %p\n",
		   i,
		   src->s6_addr32[0], src->s6_addr32[1],
		   src->s6_addr32[2], src->s6_addr32[3],
		   ntohs(inet_sk(sk)->sport),
		   dest->s6_addr32[0], dest->s6_addr32[1],
		   dest->s6_addr32[2], dest->s6_addr32[3],
1938
		   ntohs(inet_rsk(req)->rmt_port),
L
Linus Torvalds 已提交
1939 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957
		   TCP_SYN_RECV,
		   0,0, /* could print option size, but that is af dependent. */
		   1,   /* timers active (only the expire timer) */  
		   jiffies_to_clock_t(ttd), 
		   req->retrans,
		   uid,
		   0,  /* non standard timer */  
		   0, /* open_requests have no inode */
		   0, req);
}

static void get_tcp6_sock(struct seq_file *seq, struct sock *sp, int i)
{
	struct in6_addr *dest, *src;
	__u16 destp, srcp;
	int timer_active;
	unsigned long timer_expires;
	struct inet_sock *inet = inet_sk(sp);
	struct tcp_sock *tp = tcp_sk(sp);
1958
	const struct inet_connection_sock *icsk = inet_csk(sp);
L
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	struct ipv6_pinfo *np = inet6_sk(sp);

	dest  = &np->daddr;
	src   = &np->rcv_saddr;
	destp = ntohs(inet->dport);
	srcp  = ntohs(inet->sport);
1965 1966

	if (icsk->icsk_pending == ICSK_TIME_RETRANS) {
L
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		timer_active	= 1;
1968 1969
		timer_expires	= icsk->icsk_timeout;
	} else if (icsk->icsk_pending == ICSK_TIME_PROBE0) {
L
Linus Torvalds 已提交
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		timer_active	= 4;
1971
		timer_expires	= icsk->icsk_timeout;
L
Linus Torvalds 已提交
1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991
	} else if (timer_pending(&sp->sk_timer)) {
		timer_active	= 2;
		timer_expires	= sp->sk_timer.expires;
	} else {
		timer_active	= 0;
		timer_expires = jiffies;
	}

	seq_printf(seq,
		   "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
		   "%02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %p %u %u %u %u %d\n",
		   i,
		   src->s6_addr32[0], src->s6_addr32[1],
		   src->s6_addr32[2], src->s6_addr32[3], srcp,
		   dest->s6_addr32[0], dest->s6_addr32[1],
		   dest->s6_addr32[2], dest->s6_addr32[3], destp,
		   sp->sk_state, 
		   tp->write_seq-tp->snd_una, tp->rcv_nxt-tp->copied_seq,
		   timer_active,
		   jiffies_to_clock_t(timer_expires - jiffies),
1992
		   icsk->icsk_retransmits,
L
Linus Torvalds 已提交
1993
		   sock_i_uid(sp),
1994
		   icsk->icsk_probes_out,
L
Linus Torvalds 已提交
1995 1996
		   sock_i_ino(sp),
		   atomic_read(&sp->sk_refcnt), sp,
1997 1998 1999
		   icsk->icsk_rto,
		   icsk->icsk_ack.ato,
		   (icsk->icsk_ack.quick << 1 ) | icsk->icsk_ack.pingpong,
L
Linus Torvalds 已提交
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		   tp->snd_cwnd, tp->snd_ssthresh>=0xFFFF?-1:tp->snd_ssthresh
		   );
}

static void get_timewait6_sock(struct seq_file *seq, 
2005
			       struct inet_timewait_sock *tw, int i)
L
Linus Torvalds 已提交
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{
	struct in6_addr *dest, *src;
	__u16 destp, srcp;
2009
	struct tcp6_timewait_sock *tcp6tw = tcp6_twsk((struct sock *)tw);
L
Linus Torvalds 已提交
2010 2011 2012 2013 2014
	int ttd = tw->tw_ttd - jiffies;

	if (ttd < 0)
		ttd = 0;

2015 2016
	dest = &tcp6tw->tw_v6_daddr;
	src  = &tcp6tw->tw_v6_rcv_saddr;
L
Linus Torvalds 已提交
2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090
	destp = ntohs(tw->tw_dport);
	srcp  = ntohs(tw->tw_sport);

	seq_printf(seq,
		   "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
		   "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %p\n",
		   i,
		   src->s6_addr32[0], src->s6_addr32[1],
		   src->s6_addr32[2], src->s6_addr32[3], srcp,
		   dest->s6_addr32[0], dest->s6_addr32[1],
		   dest->s6_addr32[2], dest->s6_addr32[3], destp,
		   tw->tw_substate, 0, 0,
		   3, jiffies_to_clock_t(ttd), 0, 0, 0, 0,
		   atomic_read(&tw->tw_refcnt), tw);
}

#ifdef CONFIG_PROC_FS
static int tcp6_seq_show(struct seq_file *seq, void *v)
{
	struct tcp_iter_state *st;

	if (v == SEQ_START_TOKEN) {
		seq_puts(seq,
			 "  sl  "
			 "local_address                         "
			 "remote_address                        "
			 "st tx_queue rx_queue tr tm->when retrnsmt"
			 "   uid  timeout inode\n");
		goto out;
	}
	st = seq->private;

	switch (st->state) {
	case TCP_SEQ_STATE_LISTENING:
	case TCP_SEQ_STATE_ESTABLISHED:
		get_tcp6_sock(seq, v, st->num);
		break;
	case TCP_SEQ_STATE_OPENREQ:
		get_openreq6(seq, st->syn_wait_sk, v, st->num, st->uid);
		break;
	case TCP_SEQ_STATE_TIME_WAIT:
		get_timewait6_sock(seq, v, st->num);
		break;
	}
out:
	return 0;
}

static struct file_operations tcp6_seq_fops;
static struct tcp_seq_afinfo tcp6_seq_afinfo = {
	.owner		= THIS_MODULE,
	.name		= "tcp6",
	.family		= AF_INET6,
	.seq_show	= tcp6_seq_show,
	.seq_fops	= &tcp6_seq_fops,
};

int __init tcp6_proc_init(void)
{
	return tcp_proc_register(&tcp6_seq_afinfo);
}

void tcp6_proc_exit(void)
{
	tcp_proc_unregister(&tcp6_seq_afinfo);
}
#endif

struct proto tcpv6_prot = {
	.name			= "TCPv6",
	.owner			= THIS_MODULE,
	.close			= tcp_close,
	.connect		= tcp_v6_connect,
	.disconnect		= tcp_disconnect,
2091
	.accept			= inet_csk_accept,
L
Linus Torvalds 已提交
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	.ioctl			= tcp_ioctl,
	.init			= tcp_v6_init_sock,
	.destroy		= tcp_v6_destroy_sock,
	.shutdown		= tcp_shutdown,
	.setsockopt		= tcp_setsockopt,
	.getsockopt		= tcp_getsockopt,
	.sendmsg		= tcp_sendmsg,
	.recvmsg		= tcp_recvmsg,
	.backlog_rcv		= tcp_v6_do_rcv,
	.hash			= tcp_v6_hash,
	.unhash			= tcp_unhash,
	.get_port		= tcp_v6_get_port,
	.enter_memory_pressure	= tcp_enter_memory_pressure,
	.sockets_allocated	= &tcp_sockets_allocated,
	.memory_allocated	= &tcp_memory_allocated,
	.memory_pressure	= &tcp_memory_pressure,
2108
	.orphan_count		= &tcp_orphan_count,
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	.sysctl_mem		= sysctl_tcp_mem,
	.sysctl_wmem		= sysctl_tcp_wmem,
	.sysctl_rmem		= sysctl_tcp_rmem,
	.max_header		= MAX_TCP_HEADER,
	.obj_size		= sizeof(struct tcp6_sock),
2114
	.twsk_obj_size		= sizeof(struct tcp6_timewait_sock),
2115
	.rsk_prot		= &tcp6_request_sock_ops,
L
Linus Torvalds 已提交
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};

static struct inet6_protocol tcpv6_protocol = {
	.handler	=	tcp_v6_rcv,
	.err_handler	=	tcp_v6_err,
	.flags		=	INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
};

static struct inet_protosw tcpv6_protosw = {
	.type		=	SOCK_STREAM,
	.protocol	=	IPPROTO_TCP,
	.prot		=	&tcpv6_prot,
	.ops		=	&inet6_stream_ops,
	.capability	=	-1,
	.no_check	=	0,
	.flags		=	INET_PROTOSW_PERMANENT,
};

void __init tcpv6_init(void)
{
	/* register inet6 protocol */
	if (inet6_add_protocol(&tcpv6_protocol, IPPROTO_TCP) < 0)
		printk(KERN_ERR "tcpv6_init: Could not register protocol\n");
	inet6_register_protosw(&tcpv6_protosw);
}