datagram.c 20.0 KB
Newer Older
L
Linus Torvalds 已提交
1 2
/*
 *	common UDP/RAW code
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 9 10 11 12 13
 *
 *	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.
 */

14
#include <linux/capability.h>
L
Linus Torvalds 已提交
15 16 17 18 19 20 21 22 23
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/socket.h>
#include <linux/sockios.h>
#include <linux/in6.h>
#include <linux/ipv6.h>
#include <linux/route.h>
24
#include <linux/slab.h>
25
#include <linux/export.h>
L
Linus Torvalds 已提交
26 27 28 29 30 31

#include <net/ipv6.h>
#include <net/ndisc.h>
#include <net/addrconf.h>
#include <net/transp_v6.h>
#include <net/ip6_route.h>
32
#include <net/tcp_states.h>
L
Linus Torvalds 已提交
33 34 35 36

#include <linux/errqueue.h>
#include <asm/uaccess.h>

37
static bool ipv6_mapped_addr_any(const struct in6_addr *a)
38
{
39
	return ipv6_addr_v4mapped(a) && (a->s6_addr32[3] == 0);
40 41
}

L
Linus Torvalds 已提交
42 43 44 45 46
int ip6_datagram_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);
47
	struct in6_addr		*daddr, *final_p, final;
L
Linus Torvalds 已提交
48
	struct dst_entry	*dst;
49
	struct flowi6		fl6;
L
Linus Torvalds 已提交
50
	struct ip6_flowlabel	*flowlabel = NULL;
51
	struct ipv6_txoptions   *opt;
L
Linus Torvalds 已提交
52 53 54 55 56 57 58 59 60 61 62
	int			addr_type;
	int			err;

	if (usin->sin6_family == AF_INET) {
		if (__ipv6_only_sock(sk))
			return -EAFNOSUPPORT;
		err = ip4_datagram_connect(sk, uaddr, addr_len);
		goto ipv4_connected;
	}

	if (addr_len < SIN6_LEN_RFC2133)
63
		return -EINVAL;
L
Linus Torvalds 已提交
64

65 66
	if (usin->sin6_family != AF_INET6)
		return -EAFNOSUPPORT;
L
Linus Torvalds 已提交
67

68
	memset(&fl6, 0, sizeof(fl6));
L
Linus Torvalds 已提交
69
	if (np->sndflow) {
70 71 72
		fl6.flowlabel = usin->sin6_flowinfo&IPV6_FLOWINFO_MASK;
		if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
			flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
L
Linus Torvalds 已提交
73 74
			if (flowlabel == NULL)
				return -EINVAL;
A
Alexey Dobriyan 已提交
75
			usin->sin6_addr = flowlabel->dst;
L
Linus Torvalds 已提交
76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100
		}
	}

	addr_type = ipv6_addr_type(&usin->sin6_addr);

	if (addr_type == IPV6_ADDR_ANY) {
		/*
		 *	connect to self
		 */
		usin->sin6_addr.s6_addr[15] = 0x01;
	}

	daddr = &usin->sin6_addr;

	if (addr_type == IPV6_ADDR_MAPPED) {
		struct sockaddr_in sin;

		if (__ipv6_only_sock(sk)) {
			err = -ENETUNREACH;
			goto out;
		}
		sin.sin_family = AF_INET;
		sin.sin_addr.s_addr = daddr->s6_addr32[3];
		sin.sin_port = usin->sin6_port;

101
		err = ip4_datagram_connect(sk,
102
					   (struct sockaddr *) &sin,
L
Linus Torvalds 已提交
103 104 105 106 107
					   sizeof(sin));

ipv4_connected:
		if (err)
			goto out;
108

E
Eric Dumazet 已提交
109
		ipv6_addr_set_v4mapped(inet->inet_daddr, &np->daddr);
L
Linus Torvalds 已提交
110

111 112
		if (ipv6_addr_any(&np->saddr) ||
		    ipv6_mapped_addr_any(&np->saddr))
E
Eric Dumazet 已提交
113
			ipv6_addr_set_v4mapped(inet->inet_saddr, &np->saddr);
B
Brian Haley 已提交
114

115 116
		if (ipv6_addr_any(&np->rcv_saddr) ||
		    ipv6_mapped_addr_any(&np->rcv_saddr)) {
E
Eric Dumazet 已提交
117 118
			ipv6_addr_set_v4mapped(inet->inet_rcv_saddr,
					       &np->rcv_saddr);
E
Eric Dumazet 已提交
119 120 121
			if (sk->sk_prot->rehash)
				sk->sk_prot->rehash(sk);
		}
L
Linus Torvalds 已提交
122 123 124 125 126 127 128 129 130 131 132 133 134 135 136

		goto out;
	}

	if (addr_type&IPV6_ADDR_LINKLOCAL) {
		if (addr_len >= sizeof(struct sockaddr_in6) &&
		    usin->sin6_scope_id) {
			if (sk->sk_bound_dev_if &&
			    sk->sk_bound_dev_if != usin->sin6_scope_id) {
				err = -EINVAL;
				goto out;
			}
			sk->sk_bound_dev_if = usin->sin6_scope_id;
		}

137 138 139
		if (!sk->sk_bound_dev_if && (addr_type & IPV6_ADDR_MULTICAST))
			sk->sk_bound_dev_if = np->mcast_oif;

L
Linus Torvalds 已提交
140 141 142 143 144 145 146
		/* Connect to link-local address requires an interface */
		if (!sk->sk_bound_dev_if) {
			err = -EINVAL;
			goto out;
		}
	}

A
Alexey Dobriyan 已提交
147
	np->daddr = *daddr;
148
	np->flow_label = fl6.flowlabel;
L
Linus Torvalds 已提交
149

E
Eric Dumazet 已提交
150
	inet->inet_dport = usin->sin6_port;
L
Linus Torvalds 已提交
151 152 153 154 155 156

	/*
	 *	Check for a route to destination an obtain the
	 *	destination cache for it.
	 */

157
	fl6.flowi6_proto = sk->sk_protocol;
A
Alexey Dobriyan 已提交
158 159
	fl6.daddr = np->daddr;
	fl6.saddr = np->saddr;
160 161
	fl6.flowi6_oif = sk->sk_bound_dev_if;
	fl6.flowi6_mark = sk->sk_mark;
162 163
	fl6.fl6_dport = inet->inet_dport;
	fl6.fl6_sport = inet->inet_sport;
L
Linus Torvalds 已提交
164

165 166
	if (!fl6.flowi6_oif && (addr_type&IPV6_ADDR_MULTICAST))
		fl6.flowi6_oif = np->mcast_oif;
L
Linus Torvalds 已提交
167

168
	security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
V
Venkat Yekkirala 已提交
169

170
	opt = flowlabel ? flowlabel->opt : np->opt;
171
	final_p = fl6_update_dst(&fl6, opt, &final);
L
Linus Torvalds 已提交
172

173
	dst = ip6_dst_lookup_flow(sk, &fl6, final_p, true);
174 175 176
	err = 0;
	if (IS_ERR(dst)) {
		err = PTR_ERR(dst);
L
Linus Torvalds 已提交
177
		goto out;
178
	}
L
Linus Torvalds 已提交
179 180 181 182

	/* source address lookup done in ip6_dst_lookup */

	if (ipv6_addr_any(&np->saddr))
A
Alexey Dobriyan 已提交
183
		np->saddr = fl6.saddr;
L
Linus Torvalds 已提交
184 185

	if (ipv6_addr_any(&np->rcv_saddr)) {
A
Alexey Dobriyan 已提交
186
		np->rcv_saddr = fl6.saddr;
E
Eric Dumazet 已提交
187
		inet->inet_rcv_saddr = LOOPBACK4_IPV6;
E
Eric Dumazet 已提交
188 189
		if (sk->sk_prot->rehash)
			sk->sk_prot->rehash(sk);
L
Linus Torvalds 已提交
190 191 192
	}

	ip6_dst_store(sk, dst,
193
		      ipv6_addr_equal(&fl6.daddr, &np->daddr) ?
194 195
		      &np->daddr : NULL,
#ifdef CONFIG_IPV6_SUBTREES
196
		      ipv6_addr_equal(&fl6.saddr, &np->saddr) ?
197 198 199
		      &np->saddr :
#endif
		      NULL);
L
Linus Torvalds 已提交
200 201 202 203 204 205

	sk->sk_state = TCP_ESTABLISHED;
out:
	fl6_sock_release(flowlabel);
	return err;
}
206
EXPORT_SYMBOL_GPL(ip6_datagram_connect);
L
Linus Torvalds 已提交
207

208
void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
A
Al Viro 已提交
209
		     __be16 port, u32 info, u8 *payload)
L
Linus Torvalds 已提交
210 211
{
	struct ipv6_pinfo *np  = inet6_sk(sk);
212
	struct icmp6hdr *icmph = icmp6_hdr(skb);
L
Linus Torvalds 已提交
213 214 215 216 217 218 219 220 221
	struct sock_exterr_skb *serr;

	if (!np->recverr)
		return;

	skb = skb_clone(skb, GFP_ATOMIC);
	if (!skb)
		return;

222 223
	skb->protocol = htons(ETH_P_IPV6);

L
Linus Torvalds 已提交
224 225 226
	serr = SKB_EXT_ERR(skb);
	serr->ee.ee_errno = err;
	serr->ee.ee_origin = SO_EE_ORIGIN_ICMP6;
227
	serr->ee.ee_type = icmph->icmp6_type;
L
Linus Torvalds 已提交
228 229 230 231
	serr->ee.ee_code = icmph->icmp6_code;
	serr->ee.ee_pad = 0;
	serr->ee.ee_info = info;
	serr->ee.ee_data = 0;
232 233
	serr->addr_offset = (u8 *)&(((struct ipv6hdr *)(icmph + 1))->daddr) -
				  skb_network_header(skb);
L
Linus Torvalds 已提交
234 235 236
	serr->port = port;

	__skb_pull(skb, payload - skb->data);
237
	skb_reset_transport_header(skb);
L
Linus Torvalds 已提交
238 239 240 241 242

	if (sock_queue_err_skb(sk, skb))
		kfree_skb(skb);
}

243
void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info)
L
Linus Torvalds 已提交
244 245 246 247 248 249 250 251 252 253 254 255 256
{
	struct ipv6_pinfo *np = inet6_sk(sk);
	struct sock_exterr_skb *serr;
	struct ipv6hdr *iph;
	struct sk_buff *skb;

	if (!np->recverr)
		return;

	skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
	if (!skb)
		return;

257 258
	skb->protocol = htons(ETH_P_IPV6);

259 260
	skb_put(skb, sizeof(struct ipv6hdr));
	skb_reset_network_header(skb);
261
	iph = ipv6_hdr(skb);
A
Alexey Dobriyan 已提交
262
	iph->daddr = fl6->daddr;
L
Linus Torvalds 已提交
263 264 265 266

	serr = SKB_EXT_ERR(skb);
	serr->ee.ee_errno = err;
	serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
267
	serr->ee.ee_type = 0;
L
Linus Torvalds 已提交
268 269 270 271
	serr->ee.ee_code = 0;
	serr->ee.ee_pad = 0;
	serr->ee.ee_info = info;
	serr->ee.ee_data = 0;
272
	serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
273
	serr->port = fl6->fl6_dport;
L
Linus Torvalds 已提交
274

275
	__skb_pull(skb, skb_tail_pointer(skb) - skb->data);
276
	skb_reset_transport_header(skb);
L
Linus Torvalds 已提交
277 278 279 280 281

	if (sock_queue_err_skb(sk, skb))
		kfree_skb(skb);
}

282
void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu)
283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298
{
	struct ipv6_pinfo *np = inet6_sk(sk);
	struct ipv6hdr *iph;
	struct sk_buff *skb;
	struct ip6_mtuinfo *mtu_info;

	if (!np->rxopt.bits.rxpmtu)
		return;

	skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
	if (!skb)
		return;

	skb_put(skb, sizeof(struct ipv6hdr));
	skb_reset_network_header(skb);
	iph = ipv6_hdr(skb);
A
Alexey Dobriyan 已提交
299
	iph->daddr = fl6->daddr;
300 301 302 303 304 305 306

	mtu_info = IP6CBMTU(skb);

	mtu_info->ip6m_mtu = mtu;
	mtu_info->ip6m_addr.sin6_family = AF_INET6;
	mtu_info->ip6m_addr.sin6_port = 0;
	mtu_info->ip6m_addr.sin6_flowinfo = 0;
307
	mtu_info->ip6m_addr.sin6_scope_id = fl6->flowi6_oif;
A
Alexey Dobriyan 已提交
308
	mtu_info->ip6m_addr.sin6_addr = ipv6_hdr(skb)->daddr;
309 310 311 312 313 314 315 316

	__skb_pull(skb, skb_tail_pointer(skb) - skb->data);
	skb_reset_transport_header(skb);

	skb = xchg(&np->rxpmtu, skb);
	kfree_skb(skb);
}

317
/*
L
Linus Torvalds 已提交
318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352
 *	Handle MSG_ERRQUEUE
 */
int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len)
{
	struct ipv6_pinfo *np = inet6_sk(sk);
	struct sock_exterr_skb *serr;
	struct sk_buff *skb, *skb2;
	struct sockaddr_in6 *sin;
	struct {
		struct sock_extended_err ee;
		struct sockaddr_in6	 offender;
	} errhdr;
	int err;
	int copied;

	err = -EAGAIN;
	skb = skb_dequeue(&sk->sk_error_queue);
	if (skb == NULL)
		goto out;

	copied = skb->len;
	if (copied > len) {
		msg->msg_flags |= MSG_TRUNC;
		copied = len;
	}
	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
	if (err)
		goto out_free_skb;

	sock_recv_timestamp(msg, sk, skb);

	serr = SKB_EXT_ERR(skb);

	sin = (struct sockaddr_in6 *)msg->msg_name;
	if (sin) {
353
		const unsigned char *nh = skb_network_header(skb);
L
Linus Torvalds 已提交
354 355
		sin->sin6_family = AF_INET6;
		sin->sin6_flowinfo = 0;
356
		sin->sin6_port = serr->port;
L
Linus Torvalds 已提交
357
		sin->sin6_scope_id = 0;
358
		if (skb->protocol == htons(ETH_P_IPV6)) {
A
Alexey Dobriyan 已提交
359 360
			sin->sin6_addr =
				*(struct in6_addr *)(nh + serr->addr_offset);
L
Linus Torvalds 已提交
361
			if (np->sndflow)
362 363 364
				sin->sin6_flowinfo =
					(*(__be32 *)(nh + serr->addr_offset - 24) &
					 IPV6_FLOWINFO_MASK);
L
Linus Torvalds 已提交
365 366 367
			if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
				sin->sin6_scope_id = IP6CB(skb)->iif;
		} else {
B
Brian Haley 已提交
368 369
			ipv6_addr_set_v4mapped(*(__be32 *)(nh + serr->addr_offset),
					       &sin->sin6_addr);
L
Linus Torvalds 已提交
370 371 372 373 374 375 376 377 378 379
		}
	}

	memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
	sin = &errhdr.offender;
	sin->sin6_family = AF_UNSPEC;
	if (serr->ee.ee_origin != SO_EE_ORIGIN_LOCAL) {
		sin->sin6_family = AF_INET6;
		sin->sin6_flowinfo = 0;
		sin->sin6_scope_id = 0;
380
		if (skb->protocol == htons(ETH_P_IPV6)) {
A
Alexey Dobriyan 已提交
381
			sin->sin6_addr = ipv6_hdr(skb)->saddr;
L
Linus Torvalds 已提交
382 383 384 385 386 387 388
			if (np->rxopt.all)
				datagram_recv_ctl(sk, msg, skb);
			if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
				sin->sin6_scope_id = IP6CB(skb)->iif;
		} else {
			struct inet_sock *inet = inet_sk(sk);

B
Brian Haley 已提交
389 390
			ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
					       &sin->sin6_addr);
L
Linus Torvalds 已提交
391 392 393 394 395 396 397 398 399 400 401 402 403
			if (inet->cmsg_flags)
				ip_cmsg_recv(msg, skb);
		}
	}

	put_cmsg(msg, SOL_IPV6, IPV6_RECVERR, sizeof(errhdr), &errhdr);

	/* Now we could try to dump offended packet options */

	msg->msg_flags |= MSG_ERRQUEUE;
	err = copied;

	/* Reset and regenerate socket error */
404
	spin_lock_bh(&sk->sk_error_queue.lock);
L
Linus Torvalds 已提交
405 406 407
	sk->sk_err = 0;
	if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
		sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
408
		spin_unlock_bh(&sk->sk_error_queue.lock);
L
Linus Torvalds 已提交
409 410
		sk->sk_error_report(sk);
	} else {
411
		spin_unlock_bh(&sk->sk_error_queue.lock);
L
Linus Torvalds 已提交
412 413
	}

414
out_free_skb:
L
Linus Torvalds 已提交
415 416 417 418
	kfree_skb(skb);
out:
	return err;
}
419
EXPORT_SYMBOL_GPL(ipv6_recv_error);
L
Linus Torvalds 已提交
420

421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456
/*
 *	Handle IPV6_RECVPATHMTU
 */
int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len)
{
	struct ipv6_pinfo *np = inet6_sk(sk);
	struct sk_buff *skb;
	struct sockaddr_in6 *sin;
	struct ip6_mtuinfo mtu_info;
	int err;
	int copied;

	err = -EAGAIN;
	skb = xchg(&np->rxpmtu, NULL);
	if (skb == NULL)
		goto out;

	copied = skb->len;
	if (copied > len) {
		msg->msg_flags |= MSG_TRUNC;
		copied = len;
	}
	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
	if (err)
		goto out_free_skb;

	sock_recv_timestamp(msg, sk, skb);

	memcpy(&mtu_info, IP6CBMTU(skb), sizeof(mtu_info));

	sin = (struct sockaddr_in6 *)msg->msg_name;
	if (sin) {
		sin->sin6_family = AF_INET6;
		sin->sin6_flowinfo = 0;
		sin->sin6_port = 0;
		sin->sin6_scope_id = mtu_info.ip6m_addr.sin6_scope_id;
A
Alexey Dobriyan 已提交
457
		sin->sin6_addr = mtu_info.ip6m_addr.sin6_addr;
458 459 460 461 462 463 464 465 466 467 468
	}

	put_cmsg(msg, SOL_IPV6, IPV6_PATHMTU, sizeof(mtu_info), &mtu_info);

	err = copied;

out_free_skb:
	kfree_skb(skb);
out:
	return err;
}
L
Linus Torvalds 已提交
469 470 471 472 473 474


int datagram_recv_ctl(struct sock *sk, struct msghdr *msg, struct sk_buff *skb)
{
	struct ipv6_pinfo *np = inet6_sk(sk);
	struct inet6_skb_parm *opt = IP6CB(skb);
475
	unsigned char *nh = skb_network_header(skb);
L
Linus Torvalds 已提交
476 477 478 479 480

	if (np->rxopt.bits.rxinfo) {
		struct in6_pktinfo src_info;

		src_info.ipi6_ifindex = opt->iif;
A
Alexey Dobriyan 已提交
481
		src_info.ipi6_addr = ipv6_hdr(skb)->daddr;
L
Linus Torvalds 已提交
482 483 484 485
		put_cmsg(msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info);
	}

	if (np->rxopt.bits.rxhlim) {
486
		int hlim = ipv6_hdr(skb)->hop_limit;
L
Linus Torvalds 已提交
487 488 489
		put_cmsg(msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
	}

490
	if (np->rxopt.bits.rxtclass) {
J
Jiri Benc 已提交
491
		int tclass = ipv6_tclass(ipv6_hdr(skb));
492 493 494
		put_cmsg(msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
	}

495 496
	if (np->rxopt.bits.rxflow && (*(__be32 *)nh & IPV6_FLOWINFO_MASK)) {
		__be32 flowinfo = *(__be32 *)nh & IPV6_FLOWINFO_MASK;
L
Linus Torvalds 已提交
497 498
		put_cmsg(msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
	}
499 500

	/* HbH is allowed only once */
L
Linus Torvalds 已提交
501
	if (np->rxopt.bits.hopopts && opt->hop) {
502
		u8 *ptr = nh + opt->hop;
L
Linus Torvalds 已提交
503 504
		put_cmsg(msg, SOL_IPV6, IPV6_HOPOPTS, (ptr[1]+1)<<3, ptr);
	}
505 506 507 508 509 510 511 512

	if (opt->lastopt &&
	    (np->rxopt.bits.dstopts || np->rxopt.bits.srcrt)) {
		/*
		 * Silly enough, but we need to reparse in order to
		 * report extension headers (except for HbH)
		 * in order.
		 *
513
		 * Also note that IPV6_RECVRTHDRDSTOPTS is NOT
514 515 516 517
		 * (and WILL NOT be) defined because
		 * IPV6_RECVDSTOPTS is more generic. --yoshfuji
		 */
		unsigned int off = sizeof(struct ipv6hdr);
518
		u8 nexthdr = ipv6_hdr(skb)->nexthdr;
519 520

		while (off <= opt->lastopt) {
521
			unsigned int len;
522
			u8 *ptr = nh + off;
523

524
			switch (nexthdr) {
525 526 527 528 529 530 531 532 533 534 535 536 537 538
			case IPPROTO_DSTOPTS:
				nexthdr = ptr[0];
				len = (ptr[1] + 1) << 3;
				if (np->rxopt.bits.dstopts)
					put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, len, ptr);
				break;
			case IPPROTO_ROUTING:
				nexthdr = ptr[0];
				len = (ptr[1] + 1) << 3;
				if (np->rxopt.bits.srcrt)
					put_cmsg(msg, SOL_IPV6, IPV6_RTHDR, len, ptr);
				break;
			case IPPROTO_AH:
				nexthdr = ptr[0];
539
				len = (ptr[1] + 2) << 2;
540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555
				break;
			default:
				nexthdr = ptr[0];
				len = (ptr[1] + 1) << 3;
				break;
			}

			off += len;
		}
	}

	/* socket options in old style */
	if (np->rxopt.bits.rxoinfo) {
		struct in6_pktinfo src_info;

		src_info.ipi6_ifindex = opt->iif;
A
Alexey Dobriyan 已提交
556
		src_info.ipi6_addr = ipv6_hdr(skb)->daddr;
557 558 559
		put_cmsg(msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
	}
	if (np->rxopt.bits.rxohlim) {
560
		int hlim = ipv6_hdr(skb)->hop_limit;
561 562 563
		put_cmsg(msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
	}
	if (np->rxopt.bits.ohopopts && opt->hop) {
564
		u8 *ptr = nh + opt->hop;
565 566 567
		put_cmsg(msg, SOL_IPV6, IPV6_2292HOPOPTS, (ptr[1]+1)<<3, ptr);
	}
	if (np->rxopt.bits.odstopts && opt->dst0) {
568
		u8 *ptr = nh + opt->dst0;
569
		put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
L
Linus Torvalds 已提交
570
	}
571
	if (np->rxopt.bits.osrcrt && opt->srcrt) {
572
		struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(nh + opt->srcrt);
573
		put_cmsg(msg, SOL_IPV6, IPV6_2292RTHDR, (rthdr->hdrlen+1) << 3, rthdr);
L
Linus Torvalds 已提交
574
	}
575
	if (np->rxopt.bits.odstopts && opt->dst1) {
576
		u8 *ptr = nh + opt->dst1;
577
		put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
L
Linus Torvalds 已提交
578
	}
579 580
	if (np->rxopt.bits.rxorigdstaddr) {
		struct sockaddr_in6 sin6;
E
Eric Dumazet 已提交
581
		__be16 *ports = (__be16 *) skb_transport_header(skb);
582 583 584 585 586 587 588 589

		if (skb_transport_offset(skb) + 4 <= skb->len) {
			/* All current transport protocols have the port numbers in the
			 * first four bytes of the transport header and this function is
			 * written with this assumption in mind.
			 */

			sin6.sin6_family = AF_INET6;
A
Alexey Dobriyan 已提交
590
			sin6.sin6_addr = ipv6_hdr(skb)->daddr;
591 592 593 594 595 596 597
			sin6.sin6_port = ports[1];
			sin6.sin6_flowinfo = 0;
			sin6.sin6_scope_id = 0;

			put_cmsg(msg, SOL_IPV6, IPV6_ORIGDSTADDR, sizeof(sin6), &sin6);
		}
	}
L
Linus Torvalds 已提交
598 599 600
	return 0;
}

601
int datagram_send_ctl(struct net *net, struct sock *sk,
602
		      struct msghdr *msg, struct flowi6 *fl6,
L
Linus Torvalds 已提交
603
		      struct ipv6_txoptions *opt,
604
		      int *hlimit, int *tclass, int *dontfrag)
L
Linus Torvalds 已提交
605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624
{
	struct in6_pktinfo *src_info;
	struct cmsghdr *cmsg;
	struct ipv6_rt_hdr *rthdr;
	struct ipv6_opt_hdr *hdr;
	int len;
	int err = 0;

	for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
		int addr_type;

		if (!CMSG_OK(msg, cmsg)) {
			err = -EINVAL;
			goto exit_f;
		}

		if (cmsg->cmsg_level != SOL_IPV6)
			continue;

		switch (cmsg->cmsg_type) {
625 626
		case IPV6_PKTINFO:
		case IPV6_2292PKTINFO:
627 628 629
		    {
			struct net_device *dev = NULL;

630
			if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct in6_pktinfo))) {
L
Linus Torvalds 已提交
631 632 633 634 635
				err = -EINVAL;
				goto exit_f;
			}

			src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
636

L
Linus Torvalds 已提交
637
			if (src_info->ipi6_ifindex) {
638 639
				if (fl6->flowi6_oif &&
				    src_info->ipi6_ifindex != fl6->flowi6_oif)
L
Linus Torvalds 已提交
640
					return -EINVAL;
641
				fl6->flowi6_oif = src_info->ipi6_ifindex;
L
Linus Torvalds 已提交
642 643
			}

644
			addr_type = __ipv6_addr_type(&src_info->ipi6_addr);
L
Linus Torvalds 已提交
645

646
			rcu_read_lock();
647 648
			if (fl6->flowi6_oif) {
				dev = dev_get_by_index_rcu(net, fl6->flowi6_oif);
649 650
				if (!dev) {
					rcu_read_unlock();
651
					return -ENODEV;
652 653 654
				}
			} else if (addr_type & IPV6_ADDR_LINKLOCAL) {
				rcu_read_unlock();
655
				return -EINVAL;
656
			}
657

658 659
			if (addr_type != IPV6_ADDR_ANY) {
				int strict = __ipv6_addr_src_scope(addr_type) <= IPV6_ADDR_SCOPE_LINKLOCAL;
660
				if (!(inet_sk(sk)->freebind || inet_sk(sk)->transparent) &&
661
				    !ipv6_chk_addr(net, &src_info->ipi6_addr,
662 663 664
						   strict ? dev : NULL, 0))
					err = -EINVAL;
				else
A
Alexey Dobriyan 已提交
665
					fl6->saddr = src_info->ipi6_addr;
L
Linus Torvalds 已提交
666
			}
667

668
			rcu_read_unlock();
L
Linus Torvalds 已提交
669

670 671 672
			if (err)
				goto exit_f;

L
Linus Torvalds 已提交
673
			break;
674
		    }
L
Linus Torvalds 已提交
675 676

		case IPV6_FLOWINFO:
677
			if (cmsg->cmsg_len < CMSG_LEN(4)) {
L
Linus Torvalds 已提交
678 679 680 681
				err = -EINVAL;
				goto exit_f;
			}

682 683
			if (fl6->flowlabel&IPV6_FLOWINFO_MASK) {
				if ((fl6->flowlabel^*(__be32 *)CMSG_DATA(cmsg))&~IPV6_FLOWINFO_MASK) {
L
Linus Torvalds 已提交
684 685 686 687
					err = -EINVAL;
					goto exit_f;
				}
			}
688
			fl6->flowlabel = IPV6_FLOWINFO_MASK & *(__be32 *)CMSG_DATA(cmsg);
L
Linus Torvalds 已提交
689 690
			break;

691
		case IPV6_2292HOPOPTS:
L
Linus Torvalds 已提交
692
		case IPV6_HOPOPTS:
693
			if (opt->hopopt || cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
L
Linus Torvalds 已提交
694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711
				err = -EINVAL;
				goto exit_f;
			}

			hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
			len = ((hdr->hdrlen + 1) << 3);
			if (cmsg->cmsg_len < CMSG_LEN(len)) {
				err = -EINVAL;
				goto exit_f;
			}
			if (!capable(CAP_NET_RAW)) {
				err = -EPERM;
				goto exit_f;
			}
			opt->opt_nflen += len;
			opt->hopopt = hdr;
			break;

712
		case IPV6_2292DSTOPTS:
713
			if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
L
Linus Torvalds 已提交
714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735
				err = -EINVAL;
				goto exit_f;
			}

			hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
			len = ((hdr->hdrlen + 1) << 3);
			if (cmsg->cmsg_len < CMSG_LEN(len)) {
				err = -EINVAL;
				goto exit_f;
			}
			if (!capable(CAP_NET_RAW)) {
				err = -EPERM;
				goto exit_f;
			}
			if (opt->dst1opt) {
				err = -EINVAL;
				goto exit_f;
			}
			opt->opt_flen += len;
			opt->dst1opt = hdr;
			break;

736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762
		case IPV6_DSTOPTS:
		case IPV6_RTHDRDSTOPTS:
			if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
				err = -EINVAL;
				goto exit_f;
			}

			hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
			len = ((hdr->hdrlen + 1) << 3);
			if (cmsg->cmsg_len < CMSG_LEN(len)) {
				err = -EINVAL;
				goto exit_f;
			}
			if (!capable(CAP_NET_RAW)) {
				err = -EPERM;
				goto exit_f;
			}
			if (cmsg->cmsg_type == IPV6_DSTOPTS) {
				opt->opt_flen += len;
				opt->dst1opt = hdr;
			} else {
				opt->opt_nflen += len;
				opt->dst0opt = hdr;
			}
			break;

		case IPV6_2292RTHDR:
L
Linus Torvalds 已提交
763
		case IPV6_RTHDR:
764
			if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_rt_hdr))) {
L
Linus Torvalds 已提交
765 766 767 768 769 770
				err = -EINVAL;
				goto exit_f;
			}

			rthdr = (struct ipv6_rt_hdr *)CMSG_DATA(cmsg);

771
			switch (rthdr->type) {
772
#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
773
			case IPV6_SRCRT_TYPE_2:
B
Brian Haley 已提交
774 775 776 777 778
				if (rthdr->hdrlen != 2 ||
				    rthdr->segments_left != 1) {
					err = -EINVAL;
					goto exit_f;
				}
779
				break;
780
#endif
781
			default:
L
Linus Torvalds 已提交
782 783 784 785 786 787
				err = -EINVAL;
				goto exit_f;
			}

			len = ((rthdr->hdrlen + 1) << 3);

788
			if (cmsg->cmsg_len < CMSG_LEN(len)) {
L
Linus Torvalds 已提交
789 790 791 792 793 794 795 796 797 798 799 800 801
				err = -EINVAL;
				goto exit_f;
			}

			/* segments left must also match */
			if ((rthdr->hdrlen >> 1) != rthdr->segments_left) {
				err = -EINVAL;
				goto exit_f;
			}

			opt->opt_nflen += len;
			opt->srcrt = rthdr;

802
			if (cmsg->cmsg_type == IPV6_2292RTHDR && opt->dst1opt) {
L
Linus Torvalds 已提交
803 804 805 806 807 808 809 810 811 812
				int dsthdrlen = ((opt->dst1opt->hdrlen+1)<<3);

				opt->opt_nflen += dsthdrlen;
				opt->dst0opt = opt->dst1opt;
				opt->dst1opt = NULL;
				opt->opt_flen -= dsthdrlen;
			}

			break;

813
		case IPV6_2292HOPLIMIT:
L
Linus Torvalds 已提交
814 815 816 817 818 819 820
		case IPV6_HOPLIMIT:
			if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
				err = -EINVAL;
				goto exit_f;
			}

			*hlimit = *(int *)CMSG_DATA(cmsg);
821 822 823 824 825
			if (*hlimit < -1 || *hlimit > 0xff) {
				err = -EINVAL;
				goto exit_f;
			}

L
Linus Torvalds 已提交
826 827
			break;

828 829 830 831 832
		case IPV6_TCLASS:
		    {
			int tc;

			err = -EINVAL;
833
			if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
834 835 836
				goto exit_f;

			tc = *(int *)CMSG_DATA(cmsg);
837
			if (tc < -1 || tc > 0xff)
838 839 840 841 842
				goto exit_f;

			err = 0;
			*tclass = tc;

843 844 845 846 847 848 849 850
			break;
		    }

		case IPV6_DONTFRAG:
		    {
			int df;

			err = -EINVAL;
851
			if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
852 853 854 855 856 857 858 859 860
				goto exit_f;

			df = *(int *)CMSG_DATA(cmsg);
			if (df < 0 || df > 1)
				goto exit_f;

			err = 0;
			*dontfrag = df;

861 862
			break;
		    }
L
Linus Torvalds 已提交
863
		default:
864
			LIMIT_NETDEBUG(KERN_DEBUG "invalid cmsg type: %d\n",
865
				       cmsg->cmsg_type);
L
Linus Torvalds 已提交
866
			err = -EINVAL;
867
			goto exit_f;
868
		}
L
Linus Torvalds 已提交
869 870 871 872 873
	}

exit_f:
	return err;
}
874
EXPORT_SYMBOL_GPL(datagram_send_ctl);