tcp_ipv6.c 55.9 KB
Newer Older
L
Linus Torvalds 已提交
1 2
/*
 *	TCP over IPv6
3
 *	Linux INET6 implementation
L
Linus Torvalds 已提交
4 5
 *
 *	Authors:
6
 *	Pedro Roque		<roque@di.fc.ul.pt>
L
Linus Torvalds 已提交
7
 *
8
 *	Based on:
L
Linus Torvalds 已提交
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
 *	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.
 */

H
Herbert Xu 已提交
26
#include <linux/bottom_half.h>
L
Linus Torvalds 已提交
27 28 29 30 31 32 33 34 35 36 37 38 39 40
#include <linux/module.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>
41
#include <linux/slab.h>
L
Linus Torvalds 已提交
42 43 44 45 46 47 48

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

#include <net/tcp.h>
#include <net/ndisc.h>
49
#include <net/inet6_hashtables.h>
50
#include <net/inet6_connection_sock.h>
L
Linus Torvalds 已提交
51 52 53 54 55 56 57 58 59 60
#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/snmp.h>
#include <net/dsfield.h>
61
#include <net/timewait_sock.h>
62
#include <net/netdma.h>
63
#include <net/inet_common.h>
L
Linus Torvalds 已提交
64 65 66 67 68 69

#include <asm/uaccess.h>

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

70 71 72 73
#include <linux/crypto.h>
#include <linux/scatterlist.h>

static void	tcp_v6_send_reset(struct sock *sk, struct sk_buff *skb);
74 75
static void	tcp_v6_reqsk_send_ack(struct sock *sk, struct sk_buff *skb,
				      struct request_sock *req);
L
Linus Torvalds 已提交
76 77

static int	tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb);
78 79 80
static void	__tcp_v6_send_check(struct sk_buff *skb,
				    struct in6_addr *saddr,
				    struct in6_addr *daddr);
L
Linus Torvalds 已提交
81

82 83
static const struct inet_connection_sock_af_ops ipv6_mapped;
static const struct inet_connection_sock_af_ops ipv6_specific;
84
#ifdef CONFIG_TCP_MD5SIG
85 86
static const struct tcp_sock_af_ops tcp_sock_ipv6_specific;
static const struct tcp_sock_af_ops tcp_sock_ipv6_mapped_specific;
87 88 89 90 91 92
#else
static struct tcp_md5sig_key *tcp_v6_md5_do_lookup(struct sock *sk,
						   struct in6_addr *addr)
{
	return NULL;
}
93
#endif
L
Linus Torvalds 已提交
94 95 96 97

static void tcp_v6_hash(struct sock *sk)
{
	if (sk->sk_state != TCP_CLOSE) {
98
		if (inet_csk(sk)->icsk_af_ops == &ipv6_mapped) {
L
Linus Torvalds 已提交
99 100 101 102
			tcp_prot.hash(sk);
			return;
		}
		local_bh_disable();
103
		__inet6_hash(sk, NULL);
L
Linus Torvalds 已提交
104 105 106 107
		local_bh_enable();
	}
}

H
Herbert Xu 已提交
108
static __inline__ __sum16 tcp_v6_check(int len,
109 110
				   struct in6_addr *saddr,
				   struct in6_addr *daddr,
111
				   __wsum base)
L
Linus Torvalds 已提交
112 113 114 115
{
	return csum_ipv6_magic(saddr, daddr, len, IPPROTO_TCP, base);
}

116
static __u32 tcp_v6_init_sequence(struct sk_buff *skb)
L
Linus Torvalds 已提交
117
{
118 119
	return secure_tcpv6_sequence_number(ipv6_hdr(skb)->daddr.s6_addr32,
					    ipv6_hdr(skb)->saddr.s6_addr32,
120 121
					    tcp_hdr(skb)->dest,
					    tcp_hdr(skb)->source);
L
Linus Torvalds 已提交
122 123
}

124
static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
L
Linus Torvalds 已提交
125 126 127
			  int addr_len)
{
	struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr;
128
	struct inet_sock *inet = inet_sk(sk);
129
	struct inet_connection_sock *icsk = inet_csk(sk);
L
Linus Torvalds 已提交
130 131 132 133 134 135 136 137
	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;

138
	if (addr_len < SIN6_LEN_RFC2133)
L
Linus Torvalds 已提交
139 140
		return -EINVAL;

141
	if (usin->sin6_family != AF_INET6)
L
Linus Torvalds 已提交
142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159
		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);
		}
	}

	/*
160 161 162 163 164
	 *	connect() to INADDR_ANY means loopback (BSD'ism).
	 */

	if(ipv6_addr_any(&usin->sin6_addr))
		usin->sin6_addr.s6_addr[15] = 0x1;
L
Linus Torvalds 已提交
165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203

	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) {
204
		u32 exthdrlen = icsk->icsk_ext_hdr_len;
L
Linus Torvalds 已提交
205 206 207 208 209 210 211 212 213 214 215
		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];

216
		icsk->icsk_af_ops = &ipv6_mapped;
L
Linus Torvalds 已提交
217
		sk->sk_backlog_rcv = tcp_v4_do_rcv;
218 219 220
#ifdef CONFIG_TCP_MD5SIG
		tp->af_specific = &tcp_sock_ipv6_mapped_specific;
#endif
L
Linus Torvalds 已提交
221 222 223 224

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

		if (err) {
225 226
			icsk->icsk_ext_hdr_len = exthdrlen;
			icsk->icsk_af_ops = &ipv6_specific;
L
Linus Torvalds 已提交
227
			sk->sk_backlog_rcv = tcp_v6_do_rcv;
228 229 230
#ifdef CONFIG_TCP_MD5SIG
			tp->af_specific = &tcp_sock_ipv6_specific;
#endif
L
Linus Torvalds 已提交
231 232
			goto failure;
		} else {
E
Eric Dumazet 已提交
233 234 235
			ipv6_addr_set_v4mapped(inet->inet_saddr, &np->saddr);
			ipv6_addr_set_v4mapped(inet->inet_rcv_saddr,
					       &np->rcv_saddr);
L
Linus Torvalds 已提交
236 237 238 239 240 241 242 243 244 245 246 247 248
		}

		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;
B
Brian Haley 已提交
249
	fl.mark = sk->sk_mark;
L
Linus Torvalds 已提交
250
	fl.fl_ip_dport = usin->sin6_port;
E
Eric Dumazet 已提交
251
	fl.fl_ip_sport = inet->inet_sport;
L
Linus Torvalds 已提交
252 253 254 255 256 257 258 259

	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;
	}

V
Venkat Yekkirala 已提交
260 261
	security_sk_classify_flow(sk, &fl);

L
Linus Torvalds 已提交
262 263 264 265 266 267
	err = ip6_dst_lookup(sk, &dst, &fl);
	if (err)
		goto failure;
	if (final_p)
		ipv6_addr_copy(&fl.fl6_dst, final_p);

A
Alexey Dobriyan 已提交
268 269
	err = __xfrm_lookup(sock_net(sk), &dst, &fl, sk, XFRM_LOOKUP_WAIT);
	if (err < 0) {
270 271 272 273 274
		if (err == -EREMOTE)
			err = ip6_dst_blackhole(sk, &dst, &fl);
		if (err < 0)
			goto failure;
	}
L
Linus Torvalds 已提交
275 276 277 278 279 280 281 282

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

	/* set the source address */
	ipv6_addr_copy(&np->saddr, saddr);
E
Eric Dumazet 已提交
283
	inet->inet_rcv_saddr = LOOPBACK4_IPV6;
L
Linus Torvalds 已提交
284

H
Herbert Xu 已提交
285
	sk->sk_gso_type = SKB_GSO_TCPV6;
286
	__ip6_dst_store(sk, dst, NULL, NULL);
L
Linus Torvalds 已提交
287

288
	icsk->icsk_ext_hdr_len = 0;
L
Linus Torvalds 已提交
289
	if (np->opt)
290 291
		icsk->icsk_ext_hdr_len = (np->opt->opt_flen +
					  np->opt->opt_nflen);
L
Linus Torvalds 已提交
292 293 294

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

E
Eric Dumazet 已提交
295
	inet->inet_dport = usin->sin6_port;
L
Linus Torvalds 已提交
296 297

	tcp_set_state(sk, TCP_SYN_SENT);
298
	err = inet6_hash_connect(&tcp_death_row, sk);
L
Linus Torvalds 已提交
299 300 301 302 303 304
	if (err)
		goto late_failure;

	if (!tp->write_seq)
		tp->write_seq = secure_tcpv6_sequence_number(np->saddr.s6_addr32,
							     np->daddr.s6_addr32,
E
Eric Dumazet 已提交
305 306
							     inet->inet_sport,
							     inet->inet_dport);
L
Linus Torvalds 已提交
307 308 309 310 311 312 313 314 315 316 317

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

	return 0;

late_failure:
	tcp_set_state(sk, TCP_CLOSE);
	__sk_dst_reset(sk);
failure:
E
Eric Dumazet 已提交
318
	inet->inet_dport = 0;
L
Linus Torvalds 已提交
319 320 321 322 323
	sk->sk_route_caps = 0;
	return err;
}

static void tcp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
324
		u8 type, u8 code, int offset, __be32 info)
L
Linus Torvalds 已提交
325 326
{
	struct ipv6hdr *hdr = (struct ipv6hdr*)skb->data;
327
	const struct tcphdr *th = (struct tcphdr *)(skb->data+offset);
L
Linus Torvalds 已提交
328 329 330
	struct ipv6_pinfo *np;
	struct sock *sk;
	int err;
331
	struct tcp_sock *tp;
L
Linus Torvalds 已提交
332
	__u32 seq;
333
	struct net *net = dev_net(skb->dev);
L
Linus Torvalds 已提交
334

335
	sk = inet6_lookup(net, &tcp_hashinfo, &hdr->daddr,
336
			th->dest, &hdr->saddr, th->source, skb->dev->ifindex);
L
Linus Torvalds 已提交
337 338

	if (sk == NULL) {
339 340
		ICMP6_INC_STATS_BH(net, __in6_dev_get(skb->dev),
				   ICMP6_MIB_INERRORS);
L
Linus Torvalds 已提交
341 342 343 344
		return;
	}

	if (sk->sk_state == TCP_TIME_WAIT) {
345
		inet_twsk_put(inet_twsk(sk));
L
Linus Torvalds 已提交
346 347 348 349 350
		return;
	}

	bh_lock_sock(sk);
	if (sock_owned_by_user(sk))
351
		NET_INC_STATS_BH(net, LINUX_MIB_LOCKDROPPEDICMPS);
L
Linus Torvalds 已提交
352 353 354 355 356

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

	tp = tcp_sk(sk);
357
	seq = ntohl(th->seq);
L
Linus Torvalds 已提交
358 359
	if (sk->sk_state != TCP_LISTEN &&
	    !between(seq, tp->snd_una, tp->snd_nxt)) {
360
		NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS);
L
Linus Torvalds 已提交
361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389
		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;
B
Brian Haley 已提交
390
			fl.mark = sk->sk_mark;
E
Eric Dumazet 已提交
391 392
			fl.fl_ip_dport = inet->inet_dport;
			fl.fl_ip_sport = inet->inet_sport;
V
Venkat Yekkirala 已提交
393
			security_skb_classify_flow(skb, &fl);
L
Linus Torvalds 已提交
394 395 396 397 398 399

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

A
Alexey Dobriyan 已提交
400
			if ((err = xfrm_lookup(net, &dst, &fl, sk, 0)) < 0) {
L
Linus Torvalds 已提交
401 402 403 404 405 406 407
				sk->sk_err_soft = -err;
				goto out;
			}

		} else
			dst_hold(dst);

408
		if (inet_csk(sk)->icsk_pmtu_cookie > dst_mtu(dst)) {
L
Linus Torvalds 已提交
409 410 411 412 413 414 415 416 417
			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);

418
	/* Might be for an request_sock */
L
Linus Torvalds 已提交
419
	switch (sk->sk_state) {
420
		struct request_sock *req, **prev;
L
Linus Torvalds 已提交
421 422 423 424
	case TCP_LISTEN:
		if (sock_owned_by_user(sk))
			goto out;

425 426
		req = inet6_csk_search_req(sk, &prev, th->dest, &hdr->daddr,
					   &hdr->saddr, inet6_iif(skb));
L
Linus Torvalds 已提交
427 428 429 430 431 432
		if (!req)
			goto out;

		/* ICMPs are not backlogged, hence we cannot get
		 * an established socket here.
		 */
433
		WARN_ON(req->sk != NULL);
L
Linus Torvalds 已提交
434

435
		if (seq != tcp_rsk(req)->snt_isn) {
436
			NET_INC_STATS_BH(net, LINUX_MIB_OUTOFWINDOWICMPS);
L
Linus Torvalds 已提交
437 438 439
			goto out;
		}

440
		inet_csk_reqsk_queue_drop(sk, req, prev);
L
Linus Torvalds 已提交
441 442 443 444
		goto out;

	case TCP_SYN_SENT:
	case TCP_SYN_RECV:  /* Cannot happen.
445
			       It can, it SYNs are crossed. --ANK */
L
Linus Torvalds 已提交
446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467
		if (!sock_owned_by_user(sk)) {
			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);
}


468 469
static int tcp_v6_send_synack(struct sock *sk, struct request_sock *req,
			      struct request_values *rvp)
L
Linus Torvalds 已提交
470
{
471
	struct inet6_request_sock *treq = inet6_rsk(req);
L
Linus Torvalds 已提交
472 473 474 475 476
	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;
477
	struct dst_entry *dst;
L
Linus Torvalds 已提交
478 479 480 481
	int err = -1;

	memset(&fl, 0, sizeof(fl));
	fl.proto = IPPROTO_TCP;
482 483
	ipv6_addr_copy(&fl.fl6_dst, &treq->rmt_addr);
	ipv6_addr_copy(&fl.fl6_src, &treq->loc_addr);
L
Linus Torvalds 已提交
484
	fl.fl6_flowlabel = 0;
485
	fl.oif = treq->iif;
B
Brian Haley 已提交
486
	fl.mark = sk->sk_mark;
487
	fl.fl_ip_dport = inet_rsk(req)->rmt_port;
488
	fl.fl_ip_sport = inet_rsk(req)->loc_port;
489
	security_req_classify_flow(req, &fl);
L
Linus Torvalds 已提交
490

491 492 493 494 495 496
	opt = np->opt;
	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;
L
Linus Torvalds 已提交
497 498
	}

499 500 501 502 503
	err = ip6_dst_lookup(sk, &dst, &fl);
	if (err)
		goto done;
	if (final_p)
		ipv6_addr_copy(&fl.fl6_dst, final_p);
A
Alexey Dobriyan 已提交
504
	if ((err = xfrm_lookup(sock_net(sk), &dst, &fl, sk, 0)) < 0)
505 506
		goto done;

507
	skb = tcp_make_synack(sk, dst, req, rvp);
L
Linus Torvalds 已提交
508
	if (skb) {
509
		__tcp_v6_send_check(skb, &treq->loc_addr, &treq->rmt_addr);
L
Linus Torvalds 已提交
510

511
		ipv6_addr_copy(&fl.fl6_dst, &treq->rmt_addr);
L
Linus Torvalds 已提交
512
		err = ip6_xmit(sk, skb, &fl, opt, 0);
513
		err = net_xmit_eval(err);
L
Linus Torvalds 已提交
514 515 516
	}

done:
517
	if (opt && opt != np->opt)
L
Linus Torvalds 已提交
518
		sock_kfree_s(sk, opt, opt->tot_len);
519
	dst_release(dst);
L
Linus Torvalds 已提交
520 521 522
	return err;
}

523 524 525 526 527 528 529
static int tcp_v6_rtx_synack(struct sock *sk, struct request_sock *req,
			     struct request_values *rvp)
{
	TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_RETRANSSEGS);
	return tcp_v6_send_synack(sk, req, rvp);
}

530 531 532 533 534 535 536 537 538 539 540 541 542 543
static inline void syn_flood_warning(struct sk_buff *skb)
{
#ifdef CONFIG_SYN_COOKIES
	if (sysctl_tcp_syncookies)
		printk(KERN_INFO
		       "TCPv6: Possible SYN flooding on port %d. "
		       "Sending cookies.\n", ntohs(tcp_hdr(skb)->dest));
	else
#endif
		printk(KERN_INFO
		       "TCPv6: Possible SYN flooding on port %d. "
		       "Dropping request.\n", ntohs(tcp_hdr(skb)->dest));
}

544
static void tcp_v6_reqsk_destructor(struct request_sock *req)
L
Linus Torvalds 已提交
545
{
546
	kfree_skb(inet6_rsk(req)->pktopts);
L
Linus Torvalds 已提交
547 548
}

549 550 551 552 553 554 555 556 557 558 559 560 561
#ifdef CONFIG_TCP_MD5SIG
static struct tcp_md5sig_key *tcp_v6_md5_do_lookup(struct sock *sk,
						   struct in6_addr *addr)
{
	struct tcp_sock *tp = tcp_sk(sk);
	int i;

	BUG_ON(tp == NULL);

	if (!tp->md5sig_info || !tp->md5sig_info->entries6)
		return NULL;

	for (i = 0; i < tp->md5sig_info->entries6; i++) {
562
		if (ipv6_addr_equal(&tp->md5sig_info->keys6[i].addr, addr))
563
			return &tp->md5sig_info->keys6[i].base;
564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583
	}
	return NULL;
}

static struct tcp_md5sig_key *tcp_v6_md5_lookup(struct sock *sk,
						struct sock *addr_sk)
{
	return tcp_v6_md5_do_lookup(sk, &inet6_sk(addr_sk)->daddr);
}

static struct tcp_md5sig_key *tcp_v6_reqsk_md5_lookup(struct sock *sk,
						      struct request_sock *req)
{
	return tcp_v6_md5_do_lookup(sk, &inet6_rsk(req)->rmt_addr);
}

static int tcp_v6_md5_do_add(struct sock *sk, struct in6_addr *peer,
			     char *newkey, u8 newkeylen)
{
	/* Add key to the list */
584
	struct tcp_md5sig_key *key;
585 586 587
	struct tcp_sock *tp = tcp_sk(sk);
	struct tcp6_md5sig_key *keys;

588
	key = tcp_v6_md5_do_lookup(sk, peer);
589 590
	if (key) {
		/* modify existing entry - just update that one */
591 592 593
		kfree(key->key);
		key->key = newkey;
		key->keylen = newkeylen;
594 595 596 597 598 599 600 601
	} else {
		/* reallocate new list if current one is full. */
		if (!tp->md5sig_info) {
			tp->md5sig_info = kzalloc(sizeof(*tp->md5sig_info), GFP_ATOMIC);
			if (!tp->md5sig_info) {
				kfree(newkey);
				return -ENOMEM;
			}
602
			sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
603
		}
604
		if (tcp_alloc_md5sig_pool(sk) == NULL) {
605 606 607
			kfree(newkey);
			return -ENOMEM;
		}
608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629
		if (tp->md5sig_info->alloced6 == tp->md5sig_info->entries6) {
			keys = kmalloc((sizeof (tp->md5sig_info->keys6[0]) *
				       (tp->md5sig_info->entries6 + 1)), GFP_ATOMIC);

			if (!keys) {
				tcp_free_md5sig_pool();
				kfree(newkey);
				return -ENOMEM;
			}

			if (tp->md5sig_info->entries6)
				memmove(keys, tp->md5sig_info->keys6,
					(sizeof (tp->md5sig_info->keys6[0]) *
					 tp->md5sig_info->entries6));

			kfree(tp->md5sig_info->keys6);
			tp->md5sig_info->keys6 = keys;
			tp->md5sig_info->alloced6++;
		}

		ipv6_addr_copy(&tp->md5sig_info->keys6[tp->md5sig_info->entries6].addr,
			       peer);
630 631
		tp->md5sig_info->keys6[tp->md5sig_info->entries6].base.key = newkey;
		tp->md5sig_info->keys6[tp->md5sig_info->entries6].base.keylen = newkeylen;
632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650

		tp->md5sig_info->entries6++;
	}
	return 0;
}

static int tcp_v6_md5_add_func(struct sock *sk, struct sock *addr_sk,
			       u8 *newkey, __u8 newkeylen)
{
	return tcp_v6_md5_do_add(sk, &inet6_sk(addr_sk)->daddr,
				 newkey, newkeylen);
}

static int tcp_v6_md5_do_del(struct sock *sk, struct in6_addr *peer)
{
	struct tcp_sock *tp = tcp_sk(sk);
	int i;

	for (i = 0; i < tp->md5sig_info->entries6; i++) {
651
		if (ipv6_addr_equal(&tp->md5sig_info->keys6[i].addr, peer)) {
652
			/* Free the key */
653
			kfree(tp->md5sig_info->keys6[i].base.key);
654 655 656 657 658
			tp->md5sig_info->entries6--;

			if (tp->md5sig_info->entries6 == 0) {
				kfree(tp->md5sig_info->keys6);
				tp->md5sig_info->keys6 = NULL;
659
				tp->md5sig_info->alloced6 = 0;
660 661 662 663 664 665 666 667
			} else {
				/* shrink the database */
				if (tp->md5sig_info->entries6 != i)
					memmove(&tp->md5sig_info->keys6[i],
						&tp->md5sig_info->keys6[i+1],
						(tp->md5sig_info->entries6 - i)
						* sizeof (tp->md5sig_info->keys6[0]));
			}
668 669
			tcp_free_md5sig_pool();
			return 0;
670 671 672 673 674 675 676 677 678 679 680 681
		}
	}
	return -ENOENT;
}

static void tcp_v6_clear_md5_list (struct sock *sk)
{
	struct tcp_sock *tp = tcp_sk(sk);
	int i;

	if (tp->md5sig_info->entries6) {
		for (i = 0; i < tp->md5sig_info->entries6; i++)
682
			kfree(tp->md5sig_info->keys6[i].base.key);
683 684 685 686 687 688 689 690 691 692
		tp->md5sig_info->entries6 = 0;
		tcp_free_md5sig_pool();
	}

	kfree(tp->md5sig_info->keys6);
	tp->md5sig_info->keys6 = NULL;
	tp->md5sig_info->alloced6 = 0;

	if (tp->md5sig_info->entries4) {
		for (i = 0; i < tp->md5sig_info->entries4; i++)
693
			kfree(tp->md5sig_info->keys4[i].base.key);
694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721
		tp->md5sig_info->entries4 = 0;
		tcp_free_md5sig_pool();
	}

	kfree(tp->md5sig_info->keys4);
	tp->md5sig_info->keys4 = NULL;
	tp->md5sig_info->alloced4 = 0;
}

static int tcp_v6_parse_md5_keys (struct sock *sk, char __user *optval,
				  int optlen)
{
	struct tcp_md5sig cmd;
	struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&cmd.tcpm_addr;
	u8 *newkey;

	if (optlen < sizeof(cmd))
		return -EINVAL;

	if (copy_from_user(&cmd, optval, sizeof(cmd)))
		return -EFAULT;

	if (sin6->sin6_family != AF_INET6)
		return -EINVAL;

	if (!cmd.tcpm_keylen) {
		if (!tcp_sk(sk)->md5sig_info)
			return -ENOENT;
B
Brian Haley 已提交
722
		if (ipv6_addr_v4mapped(&sin6->sin6_addr))
723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738
			return tcp_v4_md5_do_del(sk, sin6->sin6_addr.s6_addr32[3]);
		return tcp_v6_md5_do_del(sk, &sin6->sin6_addr);
	}

	if (cmd.tcpm_keylen > TCP_MD5SIG_MAXKEYLEN)
		return -EINVAL;

	if (!tcp_sk(sk)->md5sig_info) {
		struct tcp_sock *tp = tcp_sk(sk);
		struct tcp_md5sig_info *p;

		p = kzalloc(sizeof(struct tcp_md5sig_info), GFP_KERNEL);
		if (!p)
			return -ENOMEM;

		tp->md5sig_info = p;
739
		sk->sk_route_caps &= ~NETIF_F_GSO_MASK;
740 741
	}

A
Arnaldo Carvalho de Melo 已提交
742
	newkey = kmemdup(cmd.tcpm_key, cmd.tcpm_keylen, GFP_KERNEL);
743 744
	if (!newkey)
		return -ENOMEM;
B
Brian Haley 已提交
745
	if (ipv6_addr_v4mapped(&sin6->sin6_addr)) {
746 747 748 749 750 751
		return tcp_v4_md5_do_add(sk, sin6->sin6_addr.s6_addr32[3],
					 newkey, cmd.tcpm_keylen);
	}
	return tcp_v6_md5_do_add(sk, &sin6->sin6_addr, newkey, cmd.tcpm_keylen);
}

752 753 754
static int tcp_v6_md5_hash_pseudoheader(struct tcp_md5sig_pool *hp,
					struct in6_addr *daddr,
					struct in6_addr *saddr, int nbytes)
755 756
{
	struct tcp6_pseudohdr *bp;
757
	struct scatterlist sg;
758

759 760 761 762
	bp = &hp->md5_blk.ip6;
	/* 1. TCP pseudo-header (RFC2460) */
	ipv6_addr_copy(&bp->saddr, saddr);
	ipv6_addr_copy(&bp->daddr, daddr);
763
	bp->protocol = cpu_to_be32(IPPROTO_TCP);
A
Adam Langley 已提交
764
	bp->len = cpu_to_be32(nbytes);
765

766 767 768
	sg_init_one(&sg, bp, sizeof(*bp));
	return crypto_hash_update(&hp->md5_desc, &sg, sizeof(*bp));
}
769

770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790
static int tcp_v6_md5_hash_hdr(char *md5_hash, struct tcp_md5sig_key *key,
			       struct in6_addr *daddr, struct in6_addr *saddr,
			       struct tcphdr *th)
{
	struct tcp_md5sig_pool *hp;
	struct hash_desc *desc;

	hp = tcp_get_md5sig_pool();
	if (!hp)
		goto clear_hash_noput;
	desc = &hp->md5_desc;

	if (crypto_hash_init(desc))
		goto clear_hash;
	if (tcp_v6_md5_hash_pseudoheader(hp, daddr, saddr, th->doff << 2))
		goto clear_hash;
	if (tcp_md5_hash_header(hp, th))
		goto clear_hash;
	if (tcp_md5_hash_key(hp, key))
		goto clear_hash;
	if (crypto_hash_final(desc, md5_hash))
791 792 793 794
		goto clear_hash;

	tcp_put_md5sig_pool();
	return 0;
795

796 797 798 799
clear_hash:
	tcp_put_md5sig_pool();
clear_hash_noput:
	memset(md5_hash, 0, 16);
800
	return 1;
801 802
}

803 804 805
static int tcp_v6_md5_hash_skb(char *md5_hash, struct tcp_md5sig_key *key,
			       struct sock *sk, struct request_sock *req,
			       struct sk_buff *skb)
806 807
{
	struct in6_addr *saddr, *daddr;
808 809 810
	struct tcp_md5sig_pool *hp;
	struct hash_desc *desc;
	struct tcphdr *th = tcp_hdr(skb);
811 812 813 814

	if (sk) {
		saddr = &inet6_sk(sk)->saddr;
		daddr = &inet6_sk(sk)->daddr;
815
	} else if (req) {
816 817
		saddr = &inet6_rsk(req)->loc_addr;
		daddr = &inet6_rsk(req)->rmt_addr;
818 819 820 821
	} else {
		struct ipv6hdr *ip6h = ipv6_hdr(skb);
		saddr = &ip6h->saddr;
		daddr = &ip6h->daddr;
822
	}
823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850

	hp = tcp_get_md5sig_pool();
	if (!hp)
		goto clear_hash_noput;
	desc = &hp->md5_desc;

	if (crypto_hash_init(desc))
		goto clear_hash;

	if (tcp_v6_md5_hash_pseudoheader(hp, daddr, saddr, skb->len))
		goto clear_hash;
	if (tcp_md5_hash_header(hp, th))
		goto clear_hash;
	if (tcp_md5_hash_skb_data(hp, skb, th->doff << 2))
		goto clear_hash;
	if (tcp_md5_hash_key(hp, key))
		goto clear_hash;
	if (crypto_hash_final(desc, md5_hash))
		goto clear_hash;

	tcp_put_md5sig_pool();
	return 0;

clear_hash:
	tcp_put_md5sig_pool();
clear_hash_noput:
	memset(md5_hash, 0, 16);
	return 1;
851 852 853 854 855 856
}

static int tcp_v6_inbound_md5_hash (struct sock *sk, struct sk_buff *skb)
{
	__u8 *hash_location = NULL;
	struct tcp_md5sig_key *hash_expected;
857
	struct ipv6hdr *ip6h = ipv6_hdr(skb);
858
	struct tcphdr *th = tcp_hdr(skb);
859 860 861 862
	int genhash;
	u8 newhash[16];

	hash_expected = tcp_v6_md5_do_lookup(sk, &ip6h->saddr);
863
	hash_location = tcp_parse_md5sig_option(th);
864

865 866 867 868 869 870
	/* We've parsed the options - do we have a hash? */
	if (!hash_expected && !hash_location)
		return 0;

	if (hash_expected && !hash_location) {
		NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND);
871 872 873
		return 1;
	}

874 875
	if (!hash_expected && hash_location) {
		NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPMD5UNEXPECTED);
876 877 878 879
		return 1;
	}

	/* check the signature */
880 881 882 883
	genhash = tcp_v6_md5_hash_skb(newhash,
				      hash_expected,
				      NULL, NULL, skb);

884 885
	if (genhash || memcmp(hash_location, newhash, 16) != 0) {
		if (net_ratelimit()) {
886
			printk(KERN_INFO "MD5 Hash %s for [%pI6c]:%u->[%pI6c]:%u\n",
887
			       genhash ? "failed" : "mismatch",
888 889
			       &ip6h->saddr, ntohs(th->source),
			       &ip6h->daddr, ntohs(th->dest));
890 891 892 893 894 895 896
		}
		return 1;
	}
	return 0;
}
#endif

897
struct request_sock_ops tcp6_request_sock_ops __read_mostly = {
L
Linus Torvalds 已提交
898
	.family		=	AF_INET6,
899
	.obj_size	=	sizeof(struct tcp6_request_sock),
900
	.rtx_syn_ack	=	tcp_v6_rtx_synack,
901 902
	.send_ack	=	tcp_v6_reqsk_send_ack,
	.destructor	=	tcp_v6_reqsk_destructor,
903 904
	.send_reset	=	tcp_v6_send_reset,
	.syn_ack_timeout = 	tcp_syn_ack_timeout,
L
Linus Torvalds 已提交
905 906
};

907
#ifdef CONFIG_TCP_MD5SIG
908
static const struct tcp_request_sock_ops tcp_request_sock_ipv6_ops = {
909
	.md5_lookup	=	tcp_v6_reqsk_md5_lookup,
910
	.calc_md5_hash	=	tcp_v6_md5_hash_skb,
911
};
912
#endif
913

914 915 916
static struct timewait_sock_ops tcp6_timewait_sock_ops = {
	.twsk_obj_size	= sizeof(struct tcp6_timewait_sock),
	.twsk_unique	= tcp_twsk_unique,
917
	.twsk_destructor= tcp_twsk_destructor,
918 919
};

920 921
static void __tcp_v6_send_check(struct sk_buff *skb,
				struct in6_addr *saddr, struct in6_addr *daddr)
L
Linus Torvalds 已提交
922
{
923
	struct tcphdr *th = tcp_hdr(skb);
L
Linus Torvalds 已提交
924

925
	if (skb->ip_summed == CHECKSUM_PARTIAL) {
926
		th->check = ~tcp_v6_check(skb->len, saddr, daddr, 0);
927
		skb->csum_start = skb_transport_header(skb) - skb->head;
A
Al Viro 已提交
928
		skb->csum_offset = offsetof(struct tcphdr, check);
L
Linus Torvalds 已提交
929
	} else {
930 931 932
		th->check = tcp_v6_check(skb->len, saddr, daddr,
					 csum_partial(th, th->doff << 2,
						      skb->csum));
L
Linus Torvalds 已提交
933 934 935
	}
}

936 937 938 939 940 941 942
static void tcp_v6_send_check(struct sock *sk, int len, struct sk_buff *skb)
{
	struct ipv6_pinfo *np = inet6_sk(sk);

	__tcp_v6_send_check(skb, &np->saddr, &np->daddr);
}

943 944 945 946 947 948 949 950
static int tcp_v6_gso_send_check(struct sk_buff *skb)
{
	struct ipv6hdr *ipv6h;
	struct tcphdr *th;

	if (!pskb_may_pull(skb, sizeof(*th)))
		return -EINVAL;

951
	ipv6h = ipv6_hdr(skb);
952
	th = tcp_hdr(skb);
953 954

	th->check = 0;
955
	skb->ip_summed = CHECKSUM_PARTIAL;
956
	__tcp_v6_send_check(skb, &ipv6h->saddr, &ipv6h->daddr);
957 958
	return 0;
}
L
Linus Torvalds 已提交
959

H
Herbert Xu 已提交
960 961
static struct sk_buff **tcp6_gro_receive(struct sk_buff **head,
					 struct sk_buff *skb)
H
Herbert Xu 已提交
962
{
H
Herbert Xu 已提交
963
	struct ipv6hdr *iph = skb_gro_network_header(skb);
H
Herbert Xu 已提交
964 965 966

	switch (skb->ip_summed) {
	case CHECKSUM_COMPLETE:
967
		if (!tcp_v6_check(skb_gro_len(skb), &iph->saddr, &iph->daddr,
H
Herbert Xu 已提交
968 969 970 971 972 973 974 975 976 977 978 979 980 981
				  skb->csum)) {
			skb->ip_summed = CHECKSUM_UNNECESSARY;
			break;
		}

		/* fall through */
	case CHECKSUM_NONE:
		NAPI_GRO_CB(skb)->flush = 1;
		return NULL;
	}

	return tcp_gro_receive(head, skb);
}

H
Herbert Xu 已提交
982
static int tcp6_gro_complete(struct sk_buff *skb)
H
Herbert Xu 已提交
983 984 985 986 987 988 989 990 991 992 993
{
	struct ipv6hdr *iph = ipv6_hdr(skb);
	struct tcphdr *th = tcp_hdr(skb);

	th->check = ~tcp_v6_check(skb->len - skb_transport_offset(skb),
				  &iph->saddr, &iph->daddr, 0);
	skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6;

	return tcp_gro_complete(skb);
}

994 995
static void tcp_v6_send_response(struct sk_buff *skb, u32 seq, u32 ack, u32 win,
				 u32 ts, struct tcp_md5sig_key *key, int rst)
L
Linus Torvalds 已提交
996
{
997
	struct tcphdr *th = tcp_hdr(skb), *t1;
L
Linus Torvalds 已提交
998 999
	struct sk_buff *buff;
	struct flowi fl;
E
Eric Dumazet 已提交
1000
	struct net *net = dev_net(skb_dst(skb)->dev);
1001
	struct sock *ctl_sk = net->ipv6.tcp_sk;
1002
	unsigned int tot_len = sizeof(struct tcphdr);
E
Eric Dumazet 已提交
1003
	struct dst_entry *dst;
1004
	__be32 *topt;
L
Linus Torvalds 已提交
1005

1006 1007
	if (ts)
		tot_len += TCPOLEN_TSTAMP_ALIGNED;
1008 1009 1010 1011 1012 1013
#ifdef CONFIG_TCP_MD5SIG
	if (key)
		tot_len += TCPOLEN_MD5SIG_ALIGNED;
#endif

	buff = alloc_skb(MAX_HEADER + sizeof(struct ipv6hdr) + tot_len,
L
Linus Torvalds 已提交
1014
			 GFP_ATOMIC);
1015 1016
	if (buff == NULL)
		return;
L
Linus Torvalds 已提交
1017

1018
	skb_reserve(buff, MAX_HEADER + sizeof(struct ipv6hdr) + tot_len);
L
Linus Torvalds 已提交
1019

1020
	t1 = (struct tcphdr *) skb_push(buff, tot_len);
1021
	skb_reset_transport_header(skb);
L
Linus Torvalds 已提交
1022 1023 1024 1025 1026

	/* Swap the send and the receive. */
	memset(t1, 0, sizeof(*t1));
	t1->dest = th->source;
	t1->source = th->dest;
1027
	t1->doff = tot_len / 4;
1028 1029 1030 1031 1032
	t1->seq = htonl(seq);
	t1->ack_seq = htonl(ack);
	t1->ack = !rst || !th->ack;
	t1->rst = rst;
	t1->window = htons(win);
L
Linus Torvalds 已提交
1033

1034 1035
	topt = (__be32 *)(t1 + 1);

1036 1037 1038 1039 1040 1041 1042
	if (ts) {
		*topt++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) |
				(TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP);
		*topt++ = htonl(tcp_time_stamp);
		*topt++ = htonl(ts);
	}

1043 1044
#ifdef CONFIG_TCP_MD5SIG
	if (key) {
1045 1046 1047
		*topt++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) |
				(TCPOPT_MD5SIG << 8) | TCPOLEN_MD5SIG);
		tcp_v6_md5_hash_hdr((__u8 *)topt, key,
1048 1049
				    &ipv6_hdr(skb)->saddr,
				    &ipv6_hdr(skb)->daddr, t1);
1050 1051 1052
	}
#endif

1053
	buff->csum = csum_partial(t1, tot_len, 0);
L
Linus Torvalds 已提交
1054 1055

	memset(&fl, 0, sizeof(fl));
1056 1057
	ipv6_addr_copy(&fl.fl6_dst, &ipv6_hdr(skb)->saddr);
	ipv6_addr_copy(&fl.fl6_src, &ipv6_hdr(skb)->daddr);
L
Linus Torvalds 已提交
1058

1059
	__tcp_v6_send_check(buff, &fl.fl6_src, &fl.fl6_dst);
L
Linus Torvalds 已提交
1060 1061

	fl.proto = IPPROTO_TCP;
1062
	fl.oif = inet6_iif(skb);
L
Linus Torvalds 已提交
1063 1064
	fl.fl_ip_dport = t1->dest;
	fl.fl_ip_sport = t1->source;
V
Venkat Yekkirala 已提交
1065
	security_skb_classify_flow(skb, &fl);
L
Linus Torvalds 已提交
1066

1067 1068 1069 1070
	/* Pass a socket to ip6_dst_lookup either it is for RST
	 * Underlying function will use this to retrieve the network
	 * namespace
	 */
E
Eric Dumazet 已提交
1071 1072 1073
	if (!ip6_dst_lookup(ctl_sk, &dst, &fl)) {
		if (xfrm_lookup(net, &dst, &fl, NULL, 0) >= 0) {
			skb_dst_set(buff, dst);
1074
			ip6_xmit(ctl_sk, buff, &fl, NULL, 0);
1075
			TCP_INC_STATS_BH(net, TCP_MIB_OUTSEGS);
1076 1077
			if (rst)
				TCP_INC_STATS_BH(net, TCP_MIB_OUTRSTS);
L
Linus Torvalds 已提交
1078
			return;
A
Arnaldo Carvalho de Melo 已提交
1079
		}
L
Linus Torvalds 已提交
1080 1081 1082 1083 1084
	}

	kfree_skb(buff);
}

1085
static void tcp_v6_send_reset(struct sock *sk, struct sk_buff *skb)
L
Linus Torvalds 已提交
1086
{
1087 1088
	struct tcphdr *th = tcp_hdr(skb);
	u32 seq = 0, ack_seq = 0;
1089
	struct tcp_md5sig_key *key = NULL;
L
Linus Torvalds 已提交
1090

1091
	if (th->rst)
L
Linus Torvalds 已提交
1092 1093
		return;

1094 1095
	if (!ipv6_unicast_destination(skb))
		return;
L
Linus Torvalds 已提交
1096

1097
#ifdef CONFIG_TCP_MD5SIG
1098 1099
	if (sk)
		key = tcp_v6_md5_do_lookup(sk, &ipv6_hdr(skb)->daddr);
1100 1101
#endif

1102 1103 1104 1105 1106
	if (th->ack)
		seq = ntohl(th->ack_seq);
	else
		ack_seq = ntohl(th->seq) + th->syn + th->fin + skb->len -
			  (th->doff << 2);
L
Linus Torvalds 已提交
1107

1108 1109
	tcp_v6_send_response(skb, seq, ack_seq, 0, 0, key, 1);
}
L
Linus Torvalds 已提交
1110

1111 1112 1113 1114
static void tcp_v6_send_ack(struct sk_buff *skb, u32 seq, u32 ack, u32 win, u32 ts,
			    struct tcp_md5sig_key *key)
{
	tcp_v6_send_response(skb, seq, ack, win, ts, key, 0);
L
Linus Torvalds 已提交
1115 1116 1117 1118
}

static void tcp_v6_timewait_ack(struct sock *sk, struct sk_buff *skb)
{
1119
	struct inet_timewait_sock *tw = inet_twsk(sk);
1120
	struct tcp_timewait_sock *tcptw = tcp_twsk(sk);
L
Linus Torvalds 已提交
1121

1122
	tcp_v6_send_ack(skb, tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt,
1123
			tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale,
1124
			tcptw->tw_ts_recent, tcp_twsk_md5_key(tcptw));
L
Linus Torvalds 已提交
1125

1126
	inet_twsk_put(tw);
L
Linus Torvalds 已提交
1127 1128
}

1129 1130
static void tcp_v6_reqsk_send_ack(struct sock *sk, struct sk_buff *skb,
				  struct request_sock *req)
L
Linus Torvalds 已提交
1131
{
1132
	tcp_v6_send_ack(skb, tcp_rsk(req)->snt_isn + 1, tcp_rsk(req)->rcv_isn + 1, req->rcv_wnd, req->ts_recent,
1133
			tcp_v6_md5_do_lookup(sk, &ipv6_hdr(skb)->daddr));
L
Linus Torvalds 已提交
1134 1135 1136 1137 1138
}


static struct sock *tcp_v6_hnd_req(struct sock *sk,struct sk_buff *skb)
{
1139
	struct request_sock *req, **prev;
1140
	const struct tcphdr *th = tcp_hdr(skb);
L
Linus Torvalds 已提交
1141 1142 1143
	struct sock *nsk;

	/* Find possible connection requests. */
1144
	req = inet6_csk_search_req(sk, &prev, th->source,
1145 1146
				   &ipv6_hdr(skb)->saddr,
				   &ipv6_hdr(skb)->daddr, inet6_iif(skb));
L
Linus Torvalds 已提交
1147 1148 1149
	if (req)
		return tcp_check_req(sk, skb, req, prev);

1150
	nsk = __inet6_lookup_established(sock_net(sk), &tcp_hashinfo,
1151 1152
			&ipv6_hdr(skb)->saddr, th->source,
			&ipv6_hdr(skb)->daddr, ntohs(th->dest), inet6_iif(skb));
L
Linus Torvalds 已提交
1153 1154 1155 1156 1157 1158

	if (nsk) {
		if (nsk->sk_state != TCP_TIME_WAIT) {
			bh_lock_sock(nsk);
			return nsk;
		}
1159
		inet_twsk_put(inet_twsk(nsk));
L
Linus Torvalds 已提交
1160 1161 1162
		return NULL;
	}

1163
#ifdef CONFIG_SYN_COOKIES
L
Linus Torvalds 已提交
1164
	if (!th->rst && !th->syn && th->ack)
1165
		sk = cookie_v6_check(sk, skb);
L
Linus Torvalds 已提交
1166 1167 1168 1169 1170 1171 1172 1173 1174
#endif
	return sk;
}

/* 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)
{
1175
	struct tcp_extend_values tmp_ext;
1176
	struct tcp_options_received tmp_opt;
1177
	u8 *hash_location;
1178
	struct request_sock *req;
1179
	struct inet6_request_sock *treq;
L
Linus Torvalds 已提交
1180 1181
	struct ipv6_pinfo *np = inet6_sk(sk);
	struct tcp_sock *tp = tcp_sk(sk);
1182
	__u32 isn = TCP_SKB_CB(skb)->when;
1183 1184 1185 1186 1187
#ifdef CONFIG_SYN_COOKIES
	int want_cookie = 0;
#else
#define want_cookie 0
#endif
L
Linus Torvalds 已提交
1188 1189 1190 1191 1192

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

	if (!ipv6_unicast_destination(skb))
1193
		goto drop;
L
Linus Torvalds 已提交
1194

1195
	if (inet_csk_reqsk_queue_is_full(sk) && !isn) {
L
Linus Torvalds 已提交
1196
		if (net_ratelimit())
1197 1198 1199 1200 1201 1202
			syn_flood_warning(skb);
#ifdef CONFIG_SYN_COOKIES
		if (sysctl_tcp_syncookies)
			want_cookie = 1;
		else
#endif
1203
		goto drop;
L
Linus Torvalds 已提交
1204 1205
	}

1206
	if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1)
L
Linus Torvalds 已提交
1207 1208
		goto drop;

1209
	req = inet6_reqsk_alloc(&tcp6_request_sock_ops);
L
Linus Torvalds 已提交
1210 1211 1212
	if (req == NULL)
		goto drop;

1213 1214 1215 1216
#ifdef CONFIG_TCP_MD5SIG
	tcp_rsk(req)->af_specific = &tcp_request_sock_ipv6_ops;
#endif

L
Linus Torvalds 已提交
1217 1218 1219
	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;
1220
	tcp_parse_options(skb, &tmp_opt, &hash_location, 0);
1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251

	if (tmp_opt.cookie_plus > 0 &&
	    tmp_opt.saw_tstamp &&
	    !tp->rx_opt.cookie_out_never &&
	    (sysctl_tcp_cookie_size > 0 ||
	     (tp->cookie_values != NULL &&
	      tp->cookie_values->cookie_desired > 0))) {
		u8 *c;
		u32 *d;
		u32 *mess = &tmp_ext.cookie_bakery[COOKIE_DIGEST_WORDS];
		int l = tmp_opt.cookie_plus - TCPOLEN_COOKIE_BASE;

		if (tcp_cookie_generator(&tmp_ext.cookie_bakery[0]) != 0)
			goto drop_and_free;

		/* Secret recipe starts with IP addresses */
		d = &ipv6_hdr(skb)->daddr.s6_addr32[0];
		*mess++ ^= *d++;
		*mess++ ^= *d++;
		*mess++ ^= *d++;
		*mess++ ^= *d++;
		d = &ipv6_hdr(skb)->saddr.s6_addr32[0];
		*mess++ ^= *d++;
		*mess++ ^= *d++;
		*mess++ ^= *d++;
		*mess++ ^= *d++;

		/* plus variable length Initiator Cookie */
		c = (u8 *)mess;
		while (l-- > 0)
			*c++ ^= *hash_location++;
L
Linus Torvalds 已提交
1252

1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265
#ifdef CONFIG_SYN_COOKIES
		want_cookie = 0;	/* not our kind of cookie */
#endif
		tmp_ext.cookie_out_never = 0; /* false */
		tmp_ext.cookie_plus = tmp_opt.cookie_plus;
	} else if (!tp->rx_opt.cookie_in_always) {
		/* redundant indications, but ensure initialization. */
		tmp_ext.cookie_out_never = 1; /* true */
		tmp_ext.cookie_plus = 0;
	} else {
		goto drop_and_free;
	}
	tmp_ext.cookie_in_always = tp->rx_opt.cookie_in_always;
L
Linus Torvalds 已提交
1266

1267
	if (want_cookie && !tmp_opt.saw_tstamp)
1268 1269
		tcp_clear_options(&tmp_opt);

L
Linus Torvalds 已提交
1270 1271 1272
	tmp_opt.tstamp_ok = tmp_opt.saw_tstamp;
	tcp_openreq_init(req, &tmp_opt, skb);

1273
	treq = inet6_rsk(req);
1274 1275
	ipv6_addr_copy(&treq->rmt_addr, &ipv6_hdr(skb)->saddr);
	ipv6_addr_copy(&treq->loc_addr, &ipv6_hdr(skb)->daddr);
1276 1277 1278 1279 1280
	if (!want_cookie)
		TCP_ECN_create_request(req, tcp_hdr(skb));

	if (want_cookie) {
		isn = cookie_v6_init_sequence(sk, skb, &req->mss);
1281
		req->cookie_ts = tmp_opt.tstamp_ok;
1282 1283 1284 1285 1286 1287 1288 1289
	} else if (!isn) {
		if (ipv6_opt_accepted(sk, skb) ||
		    np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo ||
		    np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) {
			atomic_inc(&skb->users);
			treq->pktopts = skb;
		}
		treq->iif = sk->sk_bound_dev_if;
L
Linus Torvalds 已提交
1290

1291 1292 1293 1294
		/* So that link locals have meaning */
		if (!sk->sk_bound_dev_if &&
		    ipv6_addr_type(&treq->rmt_addr) & IPV6_ADDR_LINKLOCAL)
			treq->iif = inet6_iif(skb);
L
Linus Torvalds 已提交
1295

1296
		isn = tcp_v6_init_sequence(skb);
1297
	}
1298
	tcp_rsk(req)->snt_isn = isn;
L
Linus Torvalds 已提交
1299

1300 1301
	security_inet_conn_request(sk, skb, req);

1302 1303 1304
	if (tcp_v6_send_synack(sk, req,
			       (struct request_values *)&tmp_ext) ||
	    want_cookie)
1305
		goto drop_and_free;
L
Linus Torvalds 已提交
1306

1307 1308
	inet6_csk_reqsk_queue_hash_add(sk, req, TCP_TIMEOUT_INIT);
	return 0;
L
Linus Torvalds 已提交
1309

1310 1311
drop_and_free:
	reqsk_free(req);
L
Linus Torvalds 已提交
1312 1313 1314 1315 1316
drop:
	return 0; /* don't send reset */
}

static struct sock * tcp_v6_syn_recv_sock(struct sock *sk, struct sk_buff *skb,
1317
					  struct request_sock *req,
L
Linus Torvalds 已提交
1318 1319
					  struct dst_entry *dst)
{
1320
	struct inet6_request_sock *treq;
L
Linus Torvalds 已提交
1321 1322 1323 1324 1325 1326
	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;
1327 1328 1329
#ifdef CONFIG_TCP_MD5SIG
	struct tcp_md5sig_key *key;
#endif
L
Linus Torvalds 已提交
1330 1331 1332 1333 1334 1335 1336 1337

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

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

1338
		if (newsk == NULL)
L
Linus Torvalds 已提交
1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349
			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));

E
Eric Dumazet 已提交
1350
		ipv6_addr_set_v4mapped(newinet->inet_daddr, &newnp->daddr);
L
Linus Torvalds 已提交
1351

E
Eric Dumazet 已提交
1352
		ipv6_addr_set_v4mapped(newinet->inet_saddr, &newnp->saddr);
L
Linus Torvalds 已提交
1353 1354 1355

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

1356
		inet_csk(newsk)->icsk_af_ops = &ipv6_mapped;
L
Linus Torvalds 已提交
1357
		newsk->sk_backlog_rcv = tcp_v4_do_rcv;
1358 1359 1360 1361
#ifdef CONFIG_TCP_MD5SIG
		newtp->af_specific = &tcp_sock_ipv6_mapped_specific;
#endif

L
Linus Torvalds 已提交
1362 1363
		newnp->pktoptions  = NULL;
		newnp->opt	   = NULL;
1364
		newnp->mcast_oif   = inet6_iif(skb);
1365
		newnp->mcast_hops  = ipv6_hdr(skb)->hop_limit;
L
Linus Torvalds 已提交
1366

1367 1368 1369 1370
		/*
		 * 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
Linus Torvalds 已提交
1371 1372 1373
		 */

		/* It is tricky place. Until this moment IPv4 tcp
1374
		   worked with IPv6 icsk.icsk_af_ops.
L
Linus Torvalds 已提交
1375 1376
		   Sync it now.
		 */
1377
		tcp_sync_mss(newsk, inet_csk(newsk)->icsk_pmtu_cookie);
L
Linus Torvalds 已提交
1378 1379 1380 1381

		return newsk;
	}

1382
	treq = inet6_rsk(req);
L
Linus Torvalds 已提交
1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393
	opt = np->opt;

	if (sk_acceptq_is_full(sk))
		goto out_overflow;

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

		memset(&fl, 0, sizeof(fl));
		fl.proto = IPPROTO_TCP;
1394
		ipv6_addr_copy(&fl.fl6_dst, &treq->rmt_addr);
L
Linus Torvalds 已提交
1395 1396 1397 1398 1399 1400
		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;
		}
1401
		ipv6_addr_copy(&fl.fl6_src, &treq->loc_addr);
L
Linus Torvalds 已提交
1402
		fl.oif = sk->sk_bound_dev_if;
B
Brian Haley 已提交
1403
		fl.mark = sk->sk_mark;
1404
		fl.fl_ip_dport = inet_rsk(req)->rmt_port;
1405
		fl.fl_ip_sport = inet_rsk(req)->loc_port;
1406
		security_req_classify_flow(req, &fl);
L
Linus Torvalds 已提交
1407 1408 1409 1410 1411 1412 1413

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

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

A
Alexey Dobriyan 已提交
1414
		if ((xfrm_lookup(sock_net(sk), &dst, &fl, sk, 0)) < 0)
L
Linus Torvalds 已提交
1415
			goto out;
1416
	}
L
Linus Torvalds 已提交
1417 1418 1419 1420 1421

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

1422 1423 1424 1425 1426
	/*
	 * 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
Linus Torvalds 已提交
1427

1428
	newsk->sk_gso_type = SKB_GSO_TCPV6;
1429
	__ip6_dst_store(newsk, dst, NULL, NULL);
L
Linus Torvalds 已提交
1430 1431 1432 1433 1434 1435 1436 1437 1438 1439

	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));

1440 1441 1442 1443
	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
Linus Torvalds 已提交
1444

1445
	/* Now IPv6 options...
L
Linus Torvalds 已提交
1446 1447 1448 1449

	   First: no IPv4 options.
	 */
	newinet->opt = NULL;
1450
	newnp->ipv6_fl_list = NULL;
L
Linus Torvalds 已提交
1451 1452 1453 1454 1455 1456

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

	/* Clone pktoptions received with SYN */
	newnp->pktoptions = NULL;
1457 1458 1459 1460
	if (treq->pktopts != NULL) {
		newnp->pktoptions = skb_clone(treq->pktopts, GFP_ATOMIC);
		kfree_skb(treq->pktopts);
		treq->pktopts = NULL;
L
Linus Torvalds 已提交
1461 1462 1463 1464
		if (newnp->pktoptions)
			skb_set_owner_r(newnp->pktoptions, newsk);
	}
	newnp->opt	  = NULL;
1465
	newnp->mcast_oif  = inet6_iif(skb);
1466
	newnp->mcast_hops = ipv6_hdr(skb)->hop_limit;
L
Linus Torvalds 已提交
1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479

	/* 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);
	}

1480
	inet_csk(newsk)->icsk_ext_hdr_len = 0;
L
Linus Torvalds 已提交
1481
	if (newnp->opt)
1482 1483
		inet_csk(newsk)->icsk_ext_hdr_len = (newnp->opt->opt_nflen +
						     newnp->opt->opt_flen);
L
Linus Torvalds 已提交
1484

J
John Heffner 已提交
1485
	tcp_mtup_init(newsk);
L
Linus Torvalds 已提交
1486 1487 1488 1489
	tcp_sync_mss(newsk, dst_mtu(dst));
	newtp->advmss = dst_metric(dst, RTAX_ADVMSS);
	tcp_initialize_rcv_mss(newsk);

E
Eric Dumazet 已提交
1490 1491
	newinet->inet_daddr = newinet->inet_saddr = LOOPBACK4_IPV6;
	newinet->inet_rcv_saddr = LOOPBACK4_IPV6;
L
Linus Torvalds 已提交
1492

1493 1494 1495 1496 1497 1498 1499 1500
#ifdef CONFIG_TCP_MD5SIG
	/* Copy over the MD5 key from the original socket */
	if ((key = tcp_v6_md5_do_lookup(sk, &newnp->daddr)) != NULL) {
		/* We're using one, so create a matching key
		 * on the newsk structure. If we fail to get
		 * memory, then we end up not copying the key
		 * across. Shucks.
		 */
A
Arnaldo Carvalho de Melo 已提交
1501 1502
		char *newkey = kmemdup(key->key, key->keylen, GFP_ATOMIC);
		if (newkey != NULL)
1503
			tcp_v6_md5_do_add(newsk, &newnp->daddr,
1504 1505 1506 1507
					  newkey, key->keylen);
	}
#endif

1508
	__inet6_hash(newsk, NULL);
1509
	__inet_inherit_port(sk, newsk);
L
Linus Torvalds 已提交
1510 1511 1512 1513

	return newsk;

out_overflow:
1514
	NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
L
Linus Torvalds 已提交
1515
out:
1516
	NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_LISTENDROPS);
L
Linus Torvalds 已提交
1517 1518 1519 1520 1521 1522
	if (opt && opt != np->opt)
		sock_kfree_s(sk, opt, opt->tot_len);
	dst_release(dst);
	return NULL;
}

1523
static __sum16 tcp_v6_checksum_init(struct sk_buff *skb)
L
Linus Torvalds 已提交
1524
{
1525
	if (skb->ip_summed == CHECKSUM_COMPLETE) {
H
Herbert Xu 已提交
1526
		if (!tcp_v6_check(skb->len, &ipv6_hdr(skb)->saddr,
1527
				  &ipv6_hdr(skb)->daddr, skb->csum)) {
1528
			skb->ip_summed = CHECKSUM_UNNECESSARY;
L
Linus Torvalds 已提交
1529
			return 0;
1530
		}
L
Linus Torvalds 已提交
1531
	}
1532

H
Herbert Xu 已提交
1533
	skb->csum = ~csum_unfold(tcp_v6_check(skb->len,
1534 1535
					      &ipv6_hdr(skb)->saddr,
					      &ipv6_hdr(skb)->daddr, 0));
1536

L
Linus Torvalds 已提交
1537
	if (skb->len <= 76) {
1538
		return __skb_checksum_complete(skb);
L
Linus Torvalds 已提交
1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567
	}
	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);

1568 1569 1570 1571 1572
#ifdef CONFIG_TCP_MD5SIG
	if (tcp_v6_inbound_md5_hash (sk, skb))
		goto discard;
#endif

1573
	if (sk_filter(sk, skb))
L
Linus Torvalds 已提交
1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591
		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.
1592
					       --ANK (980728)
L
Linus Torvalds 已提交
1593 1594 1595 1596 1597 1598
	 */
	if (np->rxopt.all)
		opt_skb = skb_clone(skb, GFP_ATOMIC);

	if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */
		TCP_CHECK_TIMER(sk);
1599
		if (tcp_rcv_established(sk, skb, tcp_hdr(skb), skb->len))
L
Linus Torvalds 已提交
1600 1601 1602 1603 1604 1605 1606
			goto reset;
		TCP_CHECK_TIMER(sk);
		if (opt_skb)
			goto ipv6_pktoptions;
		return 0;
	}

1607
	if (skb->len < tcp_hdrlen(skb) || tcp_checksum_complete(skb))
L
Linus Torvalds 已提交
1608 1609
		goto csum_err;

1610
	if (sk->sk_state == TCP_LISTEN) {
L
Linus Torvalds 已提交
1611 1612 1613 1614 1615 1616 1617 1618 1619
		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..
		 */
1620
		if(nsk != sk) {
L
Linus Torvalds 已提交
1621 1622 1623 1624 1625 1626 1627 1628 1629
			if (tcp_child_process(sk, nsk, skb))
				goto reset;
			if (opt_skb)
				__kfree_skb(opt_skb);
			return 0;
		}
	}

	TCP_CHECK_TIMER(sk);
1630
	if (tcp_rcv_state_process(sk, skb, tcp_hdr(skb), skb->len))
L
Linus Torvalds 已提交
1631 1632 1633 1634 1635 1636 1637
		goto reset;
	TCP_CHECK_TIMER(sk);
	if (opt_skb)
		goto ipv6_pktoptions;
	return 0;

reset:
1638
	tcp_v6_send_reset(sk, skb);
L
Linus Torvalds 已提交
1639 1640 1641 1642 1643 1644
discard:
	if (opt_skb)
		__kfree_skb(opt_skb);
	kfree_skb(skb);
	return 0;
csum_err:
1645
	TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_INERRS);
L
Linus Torvalds 已提交
1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659
	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))) {
1660
		if (np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo)
1661
			np->mcast_oif = inet6_iif(opt_skb);
1662
		if (np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim)
1663
			np->mcast_hops = ipv6_hdr(opt_skb)->hop_limit;
L
Linus Torvalds 已提交
1664 1665 1666 1667 1668 1669 1670 1671 1672
		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);
		}
	}

1673
	kfree_skb(opt_skb);
L
Linus Torvalds 已提交
1674 1675 1676
	return 0;
}

1677
static int tcp_v6_rcv(struct sk_buff *skb)
L
Linus Torvalds 已提交
1678
{
1679
	struct tcphdr *th;
L
Linus Torvalds 已提交
1680 1681
	struct sock *sk;
	int ret;
1682
	struct net *net = dev_net(skb->dev);
L
Linus Torvalds 已提交
1683 1684 1685 1686 1687 1688 1689

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

	/*
	 *	Count it even if it's bad.
	 */
1690
	TCP_INC_STATS_BH(net, TCP_MIB_INSEGS);
L
Linus Torvalds 已提交
1691 1692 1693 1694

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

1695
	th = tcp_hdr(skb);
L
Linus Torvalds 已提交
1696 1697 1698 1699 1700 1701

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

1702
	if (!skb_csum_unnecessary(skb) && tcp_v6_checksum_init(skb))
L
Linus Torvalds 已提交
1703 1704
		goto bad_packet;

1705
	th = tcp_hdr(skb);
L
Linus Torvalds 已提交
1706 1707 1708 1709 1710
	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;
1711
	TCP_SKB_CB(skb)->flags = ipv6_get_dsfield(ipv6_hdr(skb));
L
Linus Torvalds 已提交
1712 1713
	TCP_SKB_CB(skb)->sacked = 0;

1714
	sk = __inet6_lookup_skb(&tcp_hashinfo, skb, th->source, th->dest);
L
Linus Torvalds 已提交
1715 1716 1717 1718 1719 1720 1721 1722 1723 1724
	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;

1725
	if (sk_filter(sk, skb))
L
Linus Torvalds 已提交
1726 1727 1728 1729
		goto discard_and_relse;

	skb->dev = NULL;

1730
	bh_lock_sock_nested(sk);
L
Linus Torvalds 已提交
1731 1732
	ret = 0;
	if (!sock_owned_by_user(sk)) {
C
Chris Leech 已提交
1733
#ifdef CONFIG_NET_DMA
1734
		struct tcp_sock *tp = tcp_sk(sk);
1735
		if (!tp->ucopy.dma_chan && tp->ucopy.pinned_list)
1736
			tp->ucopy.dma_chan = dma_find_channel(DMA_MEMCPY);
1737 1738 1739
		if (tp->ucopy.dma_chan)
			ret = tcp_v6_do_rcv(sk, skb);
		else
C
Chris Leech 已提交
1740 1741 1742 1743 1744
#endif
		{
			if (!tcp_prequeue(sk, skb))
				ret = tcp_v6_do_rcv(sk, skb);
		}
1745
	} else if (unlikely(sk_add_backlog(sk, skb))) {
Z
Zhu Yi 已提交
1746
		bh_unlock_sock(sk);
1747
		NET_INC_STATS_BH(net, LINUX_MIB_TCPBACKLOGDROP);
Z
Zhu Yi 已提交
1748 1749
		goto discard_and_relse;
	}
L
Linus Torvalds 已提交
1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760
	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:
1761
		TCP_INC_STATS_BH(net, TCP_MIB_INERRS);
L
Linus Torvalds 已提交
1762
	} else {
1763
		tcp_v6_send_reset(NULL, skb);
L
Linus Torvalds 已提交
1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780
	}

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)) {
1781
		inet_twsk_put(inet_twsk(sk));
L
Linus Torvalds 已提交
1782 1783 1784 1785
		goto discard_it;
	}

	if (skb->len < (th->doff<<2) || tcp_checksum_complete(skb)) {
1786
		TCP_INC_STATS_BH(net, TCP_MIB_INERRS);
1787
		inet_twsk_put(inet_twsk(sk));
L
Linus Torvalds 已提交
1788 1789 1790
		goto discard_it;
	}

1791
	switch (tcp_timewait_state_process(inet_twsk(sk), skb, th)) {
L
Linus Torvalds 已提交
1792 1793 1794 1795
	case TCP_TW_SYN:
	{
		struct sock *sk2;

1796
		sk2 = inet6_lookup_listener(dev_net(skb->dev), &tcp_hashinfo,
1797
					    &ipv6_hdr(skb)->daddr,
1798
					    ntohs(th->dest), inet6_iif(skb));
L
Linus Torvalds 已提交
1799
		if (sk2 != NULL) {
1800 1801 1802
			struct inet_timewait_sock *tw = inet_twsk(sk);
			inet_twsk_deschedule(tw, &tcp_death_row);
			inet_twsk_put(tw);
L
Linus Torvalds 已提交
1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823
			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_remember_stamp(struct sock *sk)
{
	/* Alas, not yet... */
	return 0;
}

1824
static const struct inet_connection_sock_af_ops ipv6_specific = {
1825 1826 1827 1828 1829 1830 1831 1832 1833 1834 1835
	.queue_xmit	   = inet6_csk_xmit,
	.send_check	   = tcp_v6_send_check,
	.rebuild_header	   = inet6_sk_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	   = inet6_csk_addr2sockaddr,
	.sockaddr_len	   = sizeof(struct sockaddr_in6),
1836
	.bind_conflict	   = inet6_csk_bind_conflict,
1837
#ifdef CONFIG_COMPAT
1838 1839
	.compat_setsockopt = compat_ipv6_setsockopt,
	.compat_getsockopt = compat_ipv6_getsockopt,
1840
#endif
L
Linus Torvalds 已提交
1841 1842
};

1843
#ifdef CONFIG_TCP_MD5SIG
1844
static const struct tcp_sock_af_ops tcp_sock_ipv6_specific = {
1845
	.md5_lookup	=	tcp_v6_md5_lookup,
1846
	.calc_md5_hash	=	tcp_v6_md5_hash_skb,
1847 1848 1849
	.md5_add	=	tcp_v6_md5_add_func,
	.md5_parse	=	tcp_v6_parse_md5_keys,
};
1850
#endif
1851

L
Linus Torvalds 已提交
1852 1853 1854 1855
/*
 *	TCP over IPv4 via INET6 API
 */

1856
static const struct inet_connection_sock_af_ops ipv6_mapped = {
1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867
	.queue_xmit	   = ip_queue_xmit,
	.send_check	   = tcp_v4_send_check,
	.rebuild_header	   = inet_sk_rebuild_header,
	.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	   = inet6_csk_addr2sockaddr,
	.sockaddr_len	   = sizeof(struct sockaddr_in6),
1868
	.bind_conflict	   = inet6_csk_bind_conflict,
1869
#ifdef CONFIG_COMPAT
1870 1871
	.compat_setsockopt = compat_ipv6_setsockopt,
	.compat_getsockopt = compat_ipv6_getsockopt,
1872
#endif
L
Linus Torvalds 已提交
1873 1874
};

1875
#ifdef CONFIG_TCP_MD5SIG
1876
static const struct tcp_sock_af_ops tcp_sock_ipv6_mapped_specific = {
1877
	.md5_lookup	=	tcp_v4_md5_lookup,
1878
	.calc_md5_hash	=	tcp_v4_md5_hash_skb,
1879 1880 1881
	.md5_add	=	tcp_v6_md5_add_func,
	.md5_parse	=	tcp_v6_parse_md5_keys,
};
1882
#endif
1883

L
Linus Torvalds 已提交
1884 1885 1886 1887 1888
/* 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)
{
1889
	struct inet_connection_sock *icsk = inet_csk(sk);
L
Linus Torvalds 已提交
1890 1891 1892 1893 1894 1895
	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);

1896
	icsk->icsk_rto = TCP_TIMEOUT_INIT;
L
Linus Torvalds 已提交
1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908
	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.
	 */
I
Ilpo Järvinen 已提交
1909
	tp->snd_ssthresh = TCP_INFINITE_SSTHRESH;
L
Linus Torvalds 已提交
1910
	tp->snd_cwnd_clamp = ~0;
1911
	tp->mss_cache = TCP_MSS_DEFAULT;
L
Linus Torvalds 已提交
1912 1913 1914 1915 1916

	tp->reordering = sysctl_tcp_reordering;

	sk->sk_state = TCP_CLOSE;

1917
	icsk->icsk_af_ops = &ipv6_specific;
1918
	icsk->icsk_ca_ops = &tcp_init_congestion_ops;
1919
	icsk->icsk_sync_mss = tcp_sync_mss;
L
Linus Torvalds 已提交
1920 1921 1922
	sk->sk_write_space = sk_stream_write_space;
	sock_set_flag(sk, SOCK_USE_WRITE_QUEUE);

1923 1924 1925 1926
#ifdef CONFIG_TCP_MD5SIG
	tp->af_specific = &tcp_sock_ipv6_specific;
#endif

1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939
	/* TCP Cookie Transactions */
	if (sysctl_tcp_cookie_size > 0) {
		/* Default, cookies without s_data_payload. */
		tp->cookie_values =
			kzalloc(sizeof(*tp->cookie_values),
				sk->sk_allocation);
		if (tp->cookie_values != NULL)
			kref_init(&tp->cookie_values->kref);
	}
	/* Presumed zeroed, in order of appearance:
	 *	cookie_in_always, cookie_out_never,
	 *	s_data_constant, s_data_in, s_data_out
	 */
L
Linus Torvalds 已提交
1940 1941 1942
	sk->sk_sndbuf = sysctl_tcp_wmem[1];
	sk->sk_rcvbuf = sysctl_tcp_rmem[1];

H
Herbert Xu 已提交
1943
	local_bh_disable();
1944
	percpu_counter_inc(&tcp_sockets_allocated);
H
Herbert Xu 已提交
1945
	local_bh_enable();
L
Linus Torvalds 已提交
1946 1947 1948 1949

	return 0;
}

1950
static void tcp_v6_destroy_sock(struct sock *sk)
L
Linus Torvalds 已提交
1951
{
1952 1953 1954 1955 1956
#ifdef CONFIG_TCP_MD5SIG
	/* Clean up the MD5 key list */
	if (tcp_sk(sk)->md5sig_info)
		tcp_v6_clear_md5_list(sk);
#endif
L
Linus Torvalds 已提交
1957
	tcp_v4_destroy_sock(sk);
1958
	inet6_destroy_sock(sk);
L
Linus Torvalds 已提交
1959 1960
}

1961
#ifdef CONFIG_PROC_FS
L
Linus Torvalds 已提交
1962
/* Proc filesystem TCPv6 sock list dumping. */
1963
static void get_openreq6(struct seq_file *seq,
1964
			 struct sock *sk, struct request_sock *req, int i, int uid)
L
Linus Torvalds 已提交
1965 1966
{
	int ttd = req->expires - jiffies;
1967 1968
	struct in6_addr *src = &inet6_rsk(req)->loc_addr;
	struct in6_addr *dest = &inet6_rsk(req)->rmt_addr;
L
Linus Torvalds 已提交
1969 1970 1971 1972 1973 1974 1975 1976 1977 1978

	if (ttd < 0)
		ttd = 0;

	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],
1979
		   ntohs(inet_rsk(req)->loc_port),
L
Linus Torvalds 已提交
1980 1981
		   dest->s6_addr32[0], dest->s6_addr32[1],
		   dest->s6_addr32[2], dest->s6_addr32[3],
1982
		   ntohs(inet_rsk(req)->rmt_port),
L
Linus Torvalds 已提交
1983 1984
		   TCP_SYN_RECV,
		   0,0, /* could print option size, but that is af dependent. */
1985 1986
		   1,   /* timers active (only the expire timer) */
		   jiffies_to_clock_t(ttd),
L
Linus Torvalds 已提交
1987 1988
		   req->retrans,
		   uid,
1989
		   0,  /* non standard timer */
L
Linus Torvalds 已提交
1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001
		   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);
2002
	const struct inet_connection_sock *icsk = inet_csk(sp);
L
Linus Torvalds 已提交
2003 2004 2005 2006
	struct ipv6_pinfo *np = inet6_sk(sp);

	dest  = &np->daddr;
	src   = &np->rcv_saddr;
E
Eric Dumazet 已提交
2007 2008
	destp = ntohs(inet->inet_dport);
	srcp  = ntohs(inet->inet_sport);
2009 2010

	if (icsk->icsk_pending == ICSK_TIME_RETRANS) {
L
Linus Torvalds 已提交
2011
		timer_active	= 1;
2012 2013
		timer_expires	= icsk->icsk_timeout;
	} else if (icsk->icsk_pending == ICSK_TIME_PROBE0) {
L
Linus Torvalds 已提交
2014
		timer_active	= 4;
2015
		timer_expires	= icsk->icsk_timeout;
L
Linus Torvalds 已提交
2016 2017 2018 2019 2020 2021 2022 2023 2024 2025
	} 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 "
2026
		   "%02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %p %lu %lu %u %u %d\n",
L
Linus Torvalds 已提交
2027 2028 2029 2030 2031
		   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,
2032
		   sp->sk_state,
2033 2034
		   tp->write_seq-tp->snd_una,
		   (sp->sk_state == TCP_LISTEN) ? sp->sk_ack_backlog : (tp->rcv_nxt - tp->copied_seq),
L
Linus Torvalds 已提交
2035 2036
		   timer_active,
		   jiffies_to_clock_t(timer_expires - jiffies),
2037
		   icsk->icsk_retransmits,
L
Linus Torvalds 已提交
2038
		   sock_i_uid(sp),
2039
		   icsk->icsk_probes_out,
L
Linus Torvalds 已提交
2040 2041
		   sock_i_ino(sp),
		   atomic_read(&sp->sk_refcnt), sp,
2042 2043
		   jiffies_to_clock_t(icsk->icsk_rto),
		   jiffies_to_clock_t(icsk->icsk_ack.ato),
2044
		   (icsk->icsk_ack.quick << 1 ) | icsk->icsk_ack.pingpong,
I
Ilpo Järvinen 已提交
2045 2046
		   tp->snd_cwnd,
		   tcp_in_initial_slowstart(tp) ? -1 : tp->snd_ssthresh
L
Linus Torvalds 已提交
2047 2048 2049
		   );
}

2050
static void get_timewait6_sock(struct seq_file *seq,
2051
			       struct inet_timewait_sock *tw, int i)
L
Linus Torvalds 已提交
2052 2053 2054
{
	struct in6_addr *dest, *src;
	__u16 destp, srcp;
2055
	struct inet6_timewait_sock *tw6 = inet6_twsk((struct sock *)tw);
L
Linus Torvalds 已提交
2056 2057 2058 2059 2060
	int ttd = tw->tw_ttd - jiffies;

	if (ttd < 0)
		ttd = 0;

2061 2062
	dest = &tw6->tw_v6_daddr;
	src  = &tw6->tw_v6_rcv_saddr;
L
Linus Torvalds 已提交
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 2091 2092 2093 2094 2095 2096 2097 2098 2099 2100 2101 2102 2103 2104 2105 2106 2107 2108 2109 2110 2111 2112
	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);
}

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 tcp_seq_afinfo tcp6_seq_afinfo = {
	.name		= "tcp6",
	.family		= AF_INET6,
2113 2114 2115
	.seq_fops	= {
		.owner		= THIS_MODULE,
	},
2116 2117 2118
	.seq_ops	= {
		.show		= tcp6_seq_show,
	},
L
Linus Torvalds 已提交
2119 2120
};

2121
int __net_init tcp6_proc_init(struct net *net)
L
Linus Torvalds 已提交
2122
{
2123
	return tcp_proc_register(net, &tcp6_seq_afinfo);
L
Linus Torvalds 已提交
2124 2125
}

2126
void tcp6_proc_exit(struct net *net)
L
Linus Torvalds 已提交
2127
{
2128
	tcp_proc_unregister(net, &tcp6_seq_afinfo);
L
Linus Torvalds 已提交
2129 2130 2131 2132 2133 2134 2135 2136 2137
}
#endif

struct proto tcpv6_prot = {
	.name			= "TCPv6",
	.owner			= THIS_MODULE,
	.close			= tcp_close,
	.connect		= tcp_v6_connect,
	.disconnect		= tcp_disconnect,
2138
	.accept			= inet_csk_accept,
L
Linus Torvalds 已提交
2139 2140 2141 2142 2143 2144 2145 2146 2147
	.ioctl			= tcp_ioctl,
	.init			= tcp_v6_init_sock,
	.destroy		= tcp_v6_destroy_sock,
	.shutdown		= tcp_shutdown,
	.setsockopt		= tcp_setsockopt,
	.getsockopt		= tcp_getsockopt,
	.recvmsg		= tcp_recvmsg,
	.backlog_rcv		= tcp_v6_do_rcv,
	.hash			= tcp_v6_hash,
2148 2149
	.unhash			= inet_unhash,
	.get_port		= inet_csk_get_port,
L
Linus Torvalds 已提交
2150 2151 2152 2153
	.enter_memory_pressure	= tcp_enter_memory_pressure,
	.sockets_allocated	= &tcp_sockets_allocated,
	.memory_allocated	= &tcp_memory_allocated,
	.memory_pressure	= &tcp_memory_pressure,
2154
	.orphan_count		= &tcp_orphan_count,
L
Linus Torvalds 已提交
2155 2156 2157 2158 2159
	.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),
2160
	.slab_flags		= SLAB_DESTROY_BY_RCU,
2161
	.twsk_prot		= &tcp6_timewait_sock_ops,
2162
	.rsk_prot		= &tcp6_request_sock_ops,
2163
	.h.hashinfo		= &tcp_hashinfo,
2164 2165 2166 2167
#ifdef CONFIG_COMPAT
	.compat_setsockopt	= compat_tcp_setsockopt,
	.compat_getsockopt	= compat_tcp_getsockopt,
#endif
L
Linus Torvalds 已提交
2168 2169
};

2170
static const struct inet6_protocol tcpv6_protocol = {
L
Linus Torvalds 已提交
2171 2172
	.handler	=	tcp_v6_rcv,
	.err_handler	=	tcp_v6_err,
2173
	.gso_send_check	=	tcp_v6_gso_send_check,
H
Herbert Xu 已提交
2174
	.gso_segment	=	tcp_tso_segment,
H
Herbert Xu 已提交
2175 2176
	.gro_receive	=	tcp6_gro_receive,
	.gro_complete	=	tcp6_gro_complete,
L
Linus Torvalds 已提交
2177 2178 2179 2180 2181 2182 2183 2184 2185
	.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,
	.no_check	=	0,
2186 2187
	.flags		=	INET_PROTOSW_PERMANENT |
				INET_PROTOSW_ICSK,
L
Linus Torvalds 已提交
2188 2189
};

2190
static int __net_init tcpv6_net_init(struct net *net)
2191
{
2192 2193
	return inet_ctl_sock_create(&net->ipv6.tcp_sk, PF_INET6,
				    SOCK_RAW, IPPROTO_TCP, net);
2194 2195
}

2196
static void __net_exit tcpv6_net_exit(struct net *net)
2197
{
2198
	inet_ctl_sock_destroy(net->ipv6.tcp_sk);
E
Eric W. Biederman 已提交
2199 2200
}

2201
static void __net_exit tcpv6_net_exit_batch(struct list_head *net_exit_list)
E
Eric W. Biederman 已提交
2202 2203
{
	inet_twsk_purge(&tcp_hashinfo, &tcp_death_row, AF_INET6);
2204 2205 2206
}

static struct pernet_operations tcpv6_net_ops = {
E
Eric W. Biederman 已提交
2207 2208 2209
	.init	    = tcpv6_net_init,
	.exit	    = tcpv6_net_exit,
	.exit_batch = tcpv6_net_exit_batch,
2210 2211
};

2212
int __init tcpv6_init(void)
L
Linus Torvalds 已提交
2213
{
2214 2215 2216 2217 2218 2219
	int ret;

	ret = inet6_add_protocol(&tcpv6_protocol, IPPROTO_TCP);
	if (ret)
		goto out;

L
Linus Torvalds 已提交
2220
	/* register inet6 protocol */
2221 2222 2223 2224
	ret = inet6_register_protosw(&tcpv6_protosw);
	if (ret)
		goto out_tcpv6_protocol;

2225
	ret = register_pernet_subsys(&tcpv6_net_ops);
2226 2227 2228 2229
	if (ret)
		goto out_tcpv6_protosw;
out:
	return ret;
2230

2231 2232 2233 2234 2235 2236 2237
out_tcpv6_protocol:
	inet6_del_protocol(&tcpv6_protocol, IPPROTO_TCP);
out_tcpv6_protosw:
	inet6_unregister_protosw(&tcpv6_protosw);
	goto out;
}

2238
void tcpv6_exit(void)
2239
{
2240
	unregister_pernet_subsys(&tcpv6_net_ops);
2241 2242
	inet6_unregister_protosw(&tcpv6_protosw);
	inet6_del_protocol(&tcpv6_protocol, IPPROTO_TCP);
L
Linus Torvalds 已提交
2243
}