Linux Audio

Check our new training course

Loading...
v3.15
  1/*
  2 *	common UDP/RAW code
  3 *	Linux INET6 implementation
  4 *
  5 *	Authors:
  6 *	Pedro Roque		<roque@di.fc.ul.pt>
  7 *
  8 *	This program is free software; you can redistribute it and/or
  9 *      modify it under the terms of the GNU General Public License
 10 *      as published by the Free Software Foundation; either version
 11 *      2 of the License, or (at your option) any later version.
 12 */
 13
 14#include <linux/capability.h>
 15#include <linux/errno.h>
 16#include <linux/types.h>
 17#include <linux/kernel.h>
 18#include <linux/interrupt.h>
 19#include <linux/socket.h>
 20#include <linux/sockios.h>
 21#include <linux/in6.h>
 22#include <linux/ipv6.h>
 23#include <linux/route.h>
 24#include <linux/slab.h>
 25#include <linux/export.h>
 26
 27#include <net/ipv6.h>
 28#include <net/ndisc.h>
 29#include <net/addrconf.h>
 30#include <net/transp_v6.h>
 31#include <net/ip6_route.h>
 32#include <net/tcp_states.h>
 33#include <net/dsfield.h>
 34
 35#include <linux/errqueue.h>
 36#include <asm/uaccess.h>
 37
 38static bool ipv6_mapped_addr_any(const struct in6_addr *a)
 39{
 40	return ipv6_addr_v4mapped(a) && (a->s6_addr32[3] == 0);
 41}
 42
 43int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 44{
 45	struct sockaddr_in6	*usin = (struct sockaddr_in6 *) uaddr;
 46	struct inet_sock      	*inet = inet_sk(sk);
 47	struct ipv6_pinfo      	*np = inet6_sk(sk);
 48	struct in6_addr		*daddr, *final_p, final;
 49	struct dst_entry	*dst;
 50	struct flowi6		fl6;
 51	struct ip6_flowlabel	*flowlabel = NULL;
 52	struct ipv6_txoptions   *opt;
 53	int			addr_type;
 54	int			err;
 55
 56	if (usin->sin6_family == AF_INET) {
 57		if (__ipv6_only_sock(sk))
 58			return -EAFNOSUPPORT;
 59		err = ip4_datagram_connect(sk, uaddr, addr_len);
 60		goto ipv4_connected;
 61	}
 62
 63	if (addr_len < SIN6_LEN_RFC2133)
 64		return -EINVAL;
 65
 66	if (usin->sin6_family != AF_INET6)
 67		return -EAFNOSUPPORT;
 68
 69	memset(&fl6, 0, sizeof(fl6));
 70	if (np->sndflow) {
 71		fl6.flowlabel = usin->sin6_flowinfo&IPV6_FLOWINFO_MASK;
 72		if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
 73			flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
 74			if (flowlabel == NULL)
 75				return -EINVAL;
 76		}
 77	}
 78
 79	addr_type = ipv6_addr_type(&usin->sin6_addr);
 80
 81	if (addr_type == IPV6_ADDR_ANY) {
 82		/*
 83		 *	connect to self
 84		 */
 85		usin->sin6_addr.s6_addr[15] = 0x01;
 
 
 
 
 86	}
 87
 
 
 88	daddr = &usin->sin6_addr;
 89
 90	if (addr_type == IPV6_ADDR_MAPPED) {
 91		struct sockaddr_in sin;
 92
 93		if (__ipv6_only_sock(sk)) {
 94			err = -ENETUNREACH;
 95			goto out;
 96		}
 97		sin.sin_family = AF_INET;
 98		sin.sin_addr.s_addr = daddr->s6_addr32[3];
 99		sin.sin_port = usin->sin6_port;
100
101		err = ip4_datagram_connect(sk,
102					   (struct sockaddr *) &sin,
103					   sizeof(sin));
104
105ipv4_connected:
106		if (err)
107			goto out;
108
109		ipv6_addr_set_v4mapped(inet->inet_daddr, &sk->sk_v6_daddr);
110
111		if (ipv6_addr_any(&np->saddr) ||
112		    ipv6_mapped_addr_any(&np->saddr))
113			ipv6_addr_set_v4mapped(inet->inet_saddr, &np->saddr);
114
115		if (ipv6_addr_any(&sk->sk_v6_rcv_saddr) ||
116		    ipv6_mapped_addr_any(&sk->sk_v6_rcv_saddr)) {
117			ipv6_addr_set_v4mapped(inet->inet_rcv_saddr,
118					       &sk->sk_v6_rcv_saddr);
119			if (sk->sk_prot->rehash)
120				sk->sk_prot->rehash(sk);
121		}
122
123		goto out;
124	}
125
126	if (__ipv6_addr_needs_scope_id(addr_type)) {
127		if (addr_len >= sizeof(struct sockaddr_in6) &&
128		    usin->sin6_scope_id) {
129			if (sk->sk_bound_dev_if &&
130			    sk->sk_bound_dev_if != usin->sin6_scope_id) {
131				err = -EINVAL;
132				goto out;
133			}
134			sk->sk_bound_dev_if = usin->sin6_scope_id;
135		}
136
137		if (!sk->sk_bound_dev_if && (addr_type & IPV6_ADDR_MULTICAST))
138			sk->sk_bound_dev_if = np->mcast_oif;
139
140		/* Connect to link-local address requires an interface */
141		if (!sk->sk_bound_dev_if) {
142			err = -EINVAL;
143			goto out;
144		}
145	}
146
147	sk->sk_v6_daddr = *daddr;
148	np->flow_label = fl6.flowlabel;
 
 
149
 
 
150	inet->inet_dport = usin->sin6_port;
151
152	/*
153	 *	Check for a route to destination an obtain the
154	 *	destination cache for it.
155	 */
156
157	fl6.flowi6_proto = sk->sk_protocol;
158	fl6.daddr = sk->sk_v6_daddr;
159	fl6.saddr = np->saddr;
160	fl6.flowi6_oif = sk->sk_bound_dev_if;
161	fl6.flowi6_mark = sk->sk_mark;
162	fl6.fl6_dport = inet->inet_dport;
163	fl6.fl6_sport = inet->inet_sport;
164
165	if (!fl6.flowi6_oif && (addr_type&IPV6_ADDR_MULTICAST))
166		fl6.flowi6_oif = np->mcast_oif;
167
168	security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
169
170	opt = flowlabel ? flowlabel->opt : np->opt;
171	final_p = fl6_update_dst(&fl6, opt, &final);
172
173	dst = ip6_dst_lookup_flow(sk, &fl6, final_p);
174	err = 0;
175	if (IS_ERR(dst)) {
176		err = PTR_ERR(dst);
177		goto out;
178	}
179
180	/* source address lookup done in ip6_dst_lookup */
181
182	if (ipv6_addr_any(&np->saddr))
183		np->saddr = fl6.saddr;
184
185	if (ipv6_addr_any(&sk->sk_v6_rcv_saddr)) {
186		sk->sk_v6_rcv_saddr = fl6.saddr;
187		inet->inet_rcv_saddr = LOOPBACK4_IPV6;
188		if (sk->sk_prot->rehash)
189			sk->sk_prot->rehash(sk);
190	}
191
192	ip6_dst_store(sk, dst,
193		      ipv6_addr_equal(&fl6.daddr, &sk->sk_v6_daddr) ?
194		      &sk->sk_v6_daddr : NULL,
195#ifdef CONFIG_IPV6_SUBTREES
196		      ipv6_addr_equal(&fl6.saddr, &np->saddr) ?
197		      &np->saddr :
198#endif
199		      NULL);
200
201	sk->sk_state = TCP_ESTABLISHED;
 
202out:
203	fl6_sock_release(flowlabel);
204	return err;
205}
 
 
 
 
 
 
 
 
 
 
 
206EXPORT_SYMBOL_GPL(ip6_datagram_connect);
207
208int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *uaddr,
209				 int addr_len)
210{
211	DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, uaddr);
212	if (sin6->sin6_family != AF_INET6)
213		return -EAFNOSUPPORT;
214	return ip6_datagram_connect(sk, uaddr, addr_len);
215}
216EXPORT_SYMBOL_GPL(ip6_datagram_connect_v6_only);
217
218void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
219		     __be16 port, u32 info, u8 *payload)
220{
221	struct ipv6_pinfo *np  = inet6_sk(sk);
222	struct icmp6hdr *icmph = icmp6_hdr(skb);
223	struct sock_exterr_skb *serr;
224
225	if (!np->recverr)
226		return;
227
228	skb = skb_clone(skb, GFP_ATOMIC);
229	if (!skb)
230		return;
231
232	skb->protocol = htons(ETH_P_IPV6);
233
234	serr = SKB_EXT_ERR(skb);
235	serr->ee.ee_errno = err;
236	serr->ee.ee_origin = SO_EE_ORIGIN_ICMP6;
237	serr->ee.ee_type = icmph->icmp6_type;
238	serr->ee.ee_code = icmph->icmp6_code;
239	serr->ee.ee_pad = 0;
240	serr->ee.ee_info = info;
241	serr->ee.ee_data = 0;
242	serr->addr_offset = (u8 *)&(((struct ipv6hdr *)(icmph + 1))->daddr) -
243				  skb_network_header(skb);
244	serr->port = port;
245
246	__skb_pull(skb, payload - skb->data);
247	skb_reset_transport_header(skb);
248
249	if (sock_queue_err_skb(sk, skb))
250		kfree_skb(skb);
251}
252
253void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info)
254{
255	struct ipv6_pinfo *np = inet6_sk(sk);
256	struct sock_exterr_skb *serr;
257	struct ipv6hdr *iph;
258	struct sk_buff *skb;
259
260	if (!np->recverr)
261		return;
262
263	skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
264	if (!skb)
265		return;
266
267	skb->protocol = htons(ETH_P_IPV6);
268
269	skb_put(skb, sizeof(struct ipv6hdr));
270	skb_reset_network_header(skb);
271	iph = ipv6_hdr(skb);
272	iph->daddr = fl6->daddr;
273
274	serr = SKB_EXT_ERR(skb);
275	serr->ee.ee_errno = err;
276	serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
277	serr->ee.ee_type = 0;
278	serr->ee.ee_code = 0;
279	serr->ee.ee_pad = 0;
280	serr->ee.ee_info = info;
281	serr->ee.ee_data = 0;
282	serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
283	serr->port = fl6->fl6_dport;
284
285	__skb_pull(skb, skb_tail_pointer(skb) - skb->data);
286	skb_reset_transport_header(skb);
287
288	if (sock_queue_err_skb(sk, skb))
289		kfree_skb(skb);
290}
291
292void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu)
293{
294	struct ipv6_pinfo *np = inet6_sk(sk);
295	struct ipv6hdr *iph;
296	struct sk_buff *skb;
297	struct ip6_mtuinfo *mtu_info;
298
299	if (!np->rxopt.bits.rxpmtu)
300		return;
301
302	skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
303	if (!skb)
304		return;
305
306	skb_put(skb, sizeof(struct ipv6hdr));
307	skb_reset_network_header(skb);
308	iph = ipv6_hdr(skb);
309	iph->daddr = fl6->daddr;
310
311	mtu_info = IP6CBMTU(skb);
312
313	mtu_info->ip6m_mtu = mtu;
314	mtu_info->ip6m_addr.sin6_family = AF_INET6;
315	mtu_info->ip6m_addr.sin6_port = 0;
316	mtu_info->ip6m_addr.sin6_flowinfo = 0;
317	mtu_info->ip6m_addr.sin6_scope_id = fl6->flowi6_oif;
318	mtu_info->ip6m_addr.sin6_addr = ipv6_hdr(skb)->daddr;
319
320	__skb_pull(skb, skb_tail_pointer(skb) - skb->data);
321	skb_reset_transport_header(skb);
322
323	skb = xchg(&np->rxpmtu, skb);
324	kfree_skb(skb);
325}
326
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
327/*
328 *	Handle MSG_ERRQUEUE
329 */
330int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
331{
332	struct ipv6_pinfo *np = inet6_sk(sk);
333	struct sock_exterr_skb *serr;
334	struct sk_buff *skb, *skb2;
335	DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name);
336	struct {
337		struct sock_extended_err ee;
338		struct sockaddr_in6	 offender;
339	} errhdr;
340	int err;
341	int copied;
342
343	err = -EAGAIN;
344	skb = skb_dequeue(&sk->sk_error_queue);
345	if (skb == NULL)
346		goto out;
347
348	copied = skb->len;
349	if (copied > len) {
350		msg->msg_flags |= MSG_TRUNC;
351		copied = len;
352	}
353	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
354	if (err)
355		goto out_free_skb;
356
 
357	sock_recv_timestamp(msg, sk, skb);
358
359	serr = SKB_EXT_ERR(skb);
360
361	if (sin) {
362		const unsigned char *nh = skb_network_header(skb);
363		sin->sin6_family = AF_INET6;
364		sin->sin6_flowinfo = 0;
365		sin->sin6_port = serr->port;
366		if (skb->protocol == htons(ETH_P_IPV6)) {
367			const struct ipv6hdr *ip6h = container_of((struct in6_addr *)(nh + serr->addr_offset),
368								  struct ipv6hdr, daddr);
369			sin->sin6_addr = ip6h->daddr;
370			if (np->sndflow)
371				sin->sin6_flowinfo = ip6_flowinfo(ip6h);
372			sin->sin6_scope_id =
373				ipv6_iface_scope_id(&sin->sin6_addr,
374						    IP6CB(skb)->iif);
375		} else {
376			ipv6_addr_set_v4mapped(*(__be32 *)(nh + serr->addr_offset),
377					       &sin->sin6_addr);
378			sin->sin6_scope_id = 0;
379		}
380		*addr_len = sizeof(*sin);
381	}
382
383	memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
384	sin = &errhdr.offender;
385	sin->sin6_family = AF_UNSPEC;
386	if (serr->ee.ee_origin != SO_EE_ORIGIN_LOCAL) {
 
387		sin->sin6_family = AF_INET6;
388		sin->sin6_flowinfo = 0;
389		sin->sin6_port = 0;
390		if (np->rxopt.all)
391			ip6_datagram_recv_common_ctl(sk, msg, skb);
392		if (skb->protocol == htons(ETH_P_IPV6)) {
393			sin->sin6_addr = ipv6_hdr(skb)->saddr;
394			if (np->rxopt.all)
395				ip6_datagram_recv_specific_ctl(sk, msg, skb);
396			sin->sin6_scope_id =
397				ipv6_iface_scope_id(&sin->sin6_addr,
398						    IP6CB(skb)->iif);
399		} else {
400			struct inet_sock *inet = inet_sk(sk);
401
402			ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
403					       &sin->sin6_addr);
404			sin->sin6_scope_id = 0;
405			if (inet->cmsg_flags)
406				ip_cmsg_recv(msg, skb);
407		}
408	}
409
410	put_cmsg(msg, SOL_IPV6, IPV6_RECVERR, sizeof(errhdr), &errhdr);
411
412	/* Now we could try to dump offended packet options */
413
414	msg->msg_flags |= MSG_ERRQUEUE;
415	err = copied;
416
417	/* Reset and regenerate socket error */
418	spin_lock_bh(&sk->sk_error_queue.lock);
419	sk->sk_err = 0;
420	if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
421		sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
422		spin_unlock_bh(&sk->sk_error_queue.lock);
423		sk->sk_error_report(sk);
424	} else {
425		spin_unlock_bh(&sk->sk_error_queue.lock);
426	}
427
428out_free_skb:
429	kfree_skb(skb);
430out:
431	return err;
432}
433EXPORT_SYMBOL_GPL(ipv6_recv_error);
434
435/*
436 *	Handle IPV6_RECVPATHMTU
437 */
438int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len,
439		     int *addr_len)
440{
441	struct ipv6_pinfo *np = inet6_sk(sk);
442	struct sk_buff *skb;
443	struct ip6_mtuinfo mtu_info;
444	DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name);
445	int err;
446	int copied;
447
448	err = -EAGAIN;
449	skb = xchg(&np->rxpmtu, NULL);
450	if (skb == NULL)
451		goto out;
452
453	copied = skb->len;
454	if (copied > len) {
455		msg->msg_flags |= MSG_TRUNC;
456		copied = len;
457	}
458	err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
459	if (err)
460		goto out_free_skb;
461
462	sock_recv_timestamp(msg, sk, skb);
463
464	memcpy(&mtu_info, IP6CBMTU(skb), sizeof(mtu_info));
465
466	if (sin) {
467		sin->sin6_family = AF_INET6;
468		sin->sin6_flowinfo = 0;
469		sin->sin6_port = 0;
470		sin->sin6_scope_id = mtu_info.ip6m_addr.sin6_scope_id;
471		sin->sin6_addr = mtu_info.ip6m_addr.sin6_addr;
472		*addr_len = sizeof(*sin);
473	}
474
475	put_cmsg(msg, SOL_IPV6, IPV6_PATHMTU, sizeof(mtu_info), &mtu_info);
476
477	err = copied;
478
479out_free_skb:
480	kfree_skb(skb);
481out:
482	return err;
483}
484
485
486void ip6_datagram_recv_common_ctl(struct sock *sk, struct msghdr *msg,
487				 struct sk_buff *skb)
488{
489	struct ipv6_pinfo *np = inet6_sk(sk);
490	bool is_ipv6 = skb->protocol == htons(ETH_P_IPV6);
491
492	if (np->rxopt.bits.rxinfo) {
493		struct in6_pktinfo src_info;
494
495		if (is_ipv6) {
496			src_info.ipi6_ifindex = IP6CB(skb)->iif;
497			src_info.ipi6_addr = ipv6_hdr(skb)->daddr;
498		} else {
499			src_info.ipi6_ifindex =
500				PKTINFO_SKB_CB(skb)->ipi_ifindex;
501			ipv6_addr_set_v4mapped(ip_hdr(skb)->daddr,
502					       &src_info.ipi6_addr);
503		}
504		put_cmsg(msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info);
 
 
 
505	}
506}
507
508void ip6_datagram_recv_specific_ctl(struct sock *sk, struct msghdr *msg,
509				    struct sk_buff *skb)
510{
511	struct ipv6_pinfo *np = inet6_sk(sk);
512	struct inet6_skb_parm *opt = IP6CB(skb);
513	unsigned char *nh = skb_network_header(skb);
514
515	if (np->rxopt.bits.rxhlim) {
516		int hlim = ipv6_hdr(skb)->hop_limit;
517		put_cmsg(msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
518	}
519
520	if (np->rxopt.bits.rxtclass) {
521		int tclass = ipv6_get_dsfield(ipv6_hdr(skb));
522		put_cmsg(msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
523	}
524
525	if (np->rxopt.bits.rxflow) {
526		__be32 flowinfo = ip6_flowinfo((struct ipv6hdr *)nh);
527		if (flowinfo)
528			put_cmsg(msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
529	}
530
531	/* HbH is allowed only once */
532	if (np->rxopt.bits.hopopts && opt->hop) {
533		u8 *ptr = nh + opt->hop;
534		put_cmsg(msg, SOL_IPV6, IPV6_HOPOPTS, (ptr[1]+1)<<3, ptr);
535	}
536
537	if (opt->lastopt &&
538	    (np->rxopt.bits.dstopts || np->rxopt.bits.srcrt)) {
539		/*
540		 * Silly enough, but we need to reparse in order to
541		 * report extension headers (except for HbH)
542		 * in order.
543		 *
544		 * Also note that IPV6_RECVRTHDRDSTOPTS is NOT
545		 * (and WILL NOT be) defined because
546		 * IPV6_RECVDSTOPTS is more generic. --yoshfuji
547		 */
548		unsigned int off = sizeof(struct ipv6hdr);
549		u8 nexthdr = ipv6_hdr(skb)->nexthdr;
550
551		while (off <= opt->lastopt) {
552			unsigned int len;
553			u8 *ptr = nh + off;
554
555			switch (nexthdr) {
556			case IPPROTO_DSTOPTS:
557				nexthdr = ptr[0];
558				len = (ptr[1] + 1) << 3;
559				if (np->rxopt.bits.dstopts)
560					put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, len, ptr);
561				break;
562			case IPPROTO_ROUTING:
563				nexthdr = ptr[0];
564				len = (ptr[1] + 1) << 3;
565				if (np->rxopt.bits.srcrt)
566					put_cmsg(msg, SOL_IPV6, IPV6_RTHDR, len, ptr);
567				break;
568			case IPPROTO_AH:
569				nexthdr = ptr[0];
570				len = (ptr[1] + 2) << 2;
571				break;
572			default:
573				nexthdr = ptr[0];
574				len = (ptr[1] + 1) << 3;
575				break;
576			}
577
578			off += len;
579		}
580	}
581
582	/* socket options in old style */
583	if (np->rxopt.bits.rxoinfo) {
584		struct in6_pktinfo src_info;
585
586		src_info.ipi6_ifindex = opt->iif;
587		src_info.ipi6_addr = ipv6_hdr(skb)->daddr;
588		put_cmsg(msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
589	}
590	if (np->rxopt.bits.rxohlim) {
591		int hlim = ipv6_hdr(skb)->hop_limit;
592		put_cmsg(msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
593	}
594	if (np->rxopt.bits.ohopopts && opt->hop) {
595		u8 *ptr = nh + opt->hop;
596		put_cmsg(msg, SOL_IPV6, IPV6_2292HOPOPTS, (ptr[1]+1)<<3, ptr);
597	}
598	if (np->rxopt.bits.odstopts && opt->dst0) {
599		u8 *ptr = nh + opt->dst0;
600		put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
601	}
602	if (np->rxopt.bits.osrcrt && opt->srcrt) {
603		struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(nh + opt->srcrt);
604		put_cmsg(msg, SOL_IPV6, IPV6_2292RTHDR, (rthdr->hdrlen+1) << 3, rthdr);
605	}
606	if (np->rxopt.bits.odstopts && opt->dst1) {
607		u8 *ptr = nh + opt->dst1;
608		put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
609	}
610	if (np->rxopt.bits.rxorigdstaddr) {
611		struct sockaddr_in6 sin6;
612		__be16 *ports = (__be16 *) skb_transport_header(skb);
613
614		if (skb_transport_offset(skb) + 4 <= skb->len) {
615			/* All current transport protocols have the port numbers in the
616			 * first four bytes of the transport header and this function is
617			 * written with this assumption in mind.
618			 */
619
620			sin6.sin6_family = AF_INET6;
621			sin6.sin6_addr = ipv6_hdr(skb)->daddr;
622			sin6.sin6_port = ports[1];
623			sin6.sin6_flowinfo = 0;
624			sin6.sin6_scope_id =
625				ipv6_iface_scope_id(&ipv6_hdr(skb)->daddr,
626						    opt->iif);
627
628			put_cmsg(msg, SOL_IPV6, IPV6_ORIGDSTADDR, sizeof(sin6), &sin6);
629		}
630	}
 
 
 
 
 
631}
632
633void ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg,
634			  struct sk_buff *skb)
635{
636	ip6_datagram_recv_common_ctl(sk, msg, skb);
637	ip6_datagram_recv_specific_ctl(sk, msg, skb);
638}
639EXPORT_SYMBOL_GPL(ip6_datagram_recv_ctl);
640
641int ip6_datagram_send_ctl(struct net *net, struct sock *sk,
642			  struct msghdr *msg, struct flowi6 *fl6,
643			  struct ipv6_txoptions *opt,
644			  int *hlimit, int *tclass, int *dontfrag)
645{
646	struct in6_pktinfo *src_info;
647	struct cmsghdr *cmsg;
648	struct ipv6_rt_hdr *rthdr;
649	struct ipv6_opt_hdr *hdr;
 
650	int len;
651	int err = 0;
652
653	for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
654		int addr_type;
655
656		if (!CMSG_OK(msg, cmsg)) {
657			err = -EINVAL;
658			goto exit_f;
659		}
660
 
 
 
 
 
 
 
661		if (cmsg->cmsg_level != SOL_IPV6)
662			continue;
663
664		switch (cmsg->cmsg_type) {
665		case IPV6_PKTINFO:
666		case IPV6_2292PKTINFO:
667		    {
668			struct net_device *dev = NULL;
669
670			if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct in6_pktinfo))) {
671				err = -EINVAL;
672				goto exit_f;
673			}
674
675			src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
676
677			if (src_info->ipi6_ifindex) {
678				if (fl6->flowi6_oif &&
679				    src_info->ipi6_ifindex != fl6->flowi6_oif)
680					return -EINVAL;
681				fl6->flowi6_oif = src_info->ipi6_ifindex;
682			}
683
684			addr_type = __ipv6_addr_type(&src_info->ipi6_addr);
685
686			rcu_read_lock();
687			if (fl6->flowi6_oif) {
688				dev = dev_get_by_index_rcu(net, fl6->flowi6_oif);
689				if (!dev) {
690					rcu_read_unlock();
691					return -ENODEV;
692				}
693			} else if (addr_type & IPV6_ADDR_LINKLOCAL) {
694				rcu_read_unlock();
695				return -EINVAL;
696			}
697
698			if (addr_type != IPV6_ADDR_ANY) {
699				int strict = __ipv6_addr_src_scope(addr_type) <= IPV6_ADDR_SCOPE_LINKLOCAL;
700				if (!(inet_sk(sk)->freebind || inet_sk(sk)->transparent) &&
701				    !ipv6_chk_addr(net, &src_info->ipi6_addr,
702						   strict ? dev : NULL, 0) &&
 
703				    !ipv6_chk_acast_addr_src(net, dev,
704							     &src_info->ipi6_addr))
705					err = -EINVAL;
706				else
707					fl6->saddr = src_info->ipi6_addr;
708			}
709
710			rcu_read_unlock();
711
712			if (err)
713				goto exit_f;
714
715			break;
716		    }
717
718		case IPV6_FLOWINFO:
719			if (cmsg->cmsg_len < CMSG_LEN(4)) {
720				err = -EINVAL;
721				goto exit_f;
722			}
723
724			if (fl6->flowlabel&IPV6_FLOWINFO_MASK) {
725				if ((fl6->flowlabel^*(__be32 *)CMSG_DATA(cmsg))&~IPV6_FLOWINFO_MASK) {
726					err = -EINVAL;
727					goto exit_f;
728				}
729			}
730			fl6->flowlabel = IPV6_FLOWINFO_MASK & *(__be32 *)CMSG_DATA(cmsg);
731			break;
732
733		case IPV6_2292HOPOPTS:
734		case IPV6_HOPOPTS:
735			if (opt->hopopt || cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
736				err = -EINVAL;
737				goto exit_f;
738			}
739
740			hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
741			len = ((hdr->hdrlen + 1) << 3);
742			if (cmsg->cmsg_len < CMSG_LEN(len)) {
743				err = -EINVAL;
744				goto exit_f;
745			}
746			if (!ns_capable(net->user_ns, CAP_NET_RAW)) {
747				err = -EPERM;
748				goto exit_f;
749			}
750			opt->opt_nflen += len;
751			opt->hopopt = hdr;
752			break;
753
754		case IPV6_2292DSTOPTS:
755			if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
756				err = -EINVAL;
757				goto exit_f;
758			}
759
760			hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
761			len = ((hdr->hdrlen + 1) << 3);
762			if (cmsg->cmsg_len < CMSG_LEN(len)) {
763				err = -EINVAL;
764				goto exit_f;
765			}
766			if (!ns_capable(net->user_ns, CAP_NET_RAW)) {
767				err = -EPERM;
768				goto exit_f;
769			}
770			if (opt->dst1opt) {
771				err = -EINVAL;
772				goto exit_f;
773			}
774			opt->opt_flen += len;
775			opt->dst1opt = hdr;
776			break;
777
778		case IPV6_DSTOPTS:
779		case IPV6_RTHDRDSTOPTS:
780			if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
781				err = -EINVAL;
782				goto exit_f;
783			}
784
785			hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
786			len = ((hdr->hdrlen + 1) << 3);
787			if (cmsg->cmsg_len < CMSG_LEN(len)) {
788				err = -EINVAL;
789				goto exit_f;
790			}
791			if (!ns_capable(net->user_ns, CAP_NET_RAW)) {
792				err = -EPERM;
793				goto exit_f;
794			}
795			if (cmsg->cmsg_type == IPV6_DSTOPTS) {
796				opt->opt_flen += len;
797				opt->dst1opt = hdr;
798			} else {
799				opt->opt_nflen += len;
800				opt->dst0opt = hdr;
801			}
802			break;
803
804		case IPV6_2292RTHDR:
805		case IPV6_RTHDR:
806			if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_rt_hdr))) {
807				err = -EINVAL;
808				goto exit_f;
809			}
810
811			rthdr = (struct ipv6_rt_hdr *)CMSG_DATA(cmsg);
812
813			switch (rthdr->type) {
814#if IS_ENABLED(CONFIG_IPV6_MIP6)
815			case IPV6_SRCRT_TYPE_2:
816				if (rthdr->hdrlen != 2 ||
817				    rthdr->segments_left != 1) {
818					err = -EINVAL;
819					goto exit_f;
820				}
821				break;
822#endif
823			default:
824				err = -EINVAL;
825				goto exit_f;
826			}
827
828			len = ((rthdr->hdrlen + 1) << 3);
829
830			if (cmsg->cmsg_len < CMSG_LEN(len)) {
831				err = -EINVAL;
832				goto exit_f;
833			}
834
835			/* segments left must also match */
836			if ((rthdr->hdrlen >> 1) != rthdr->segments_left) {
837				err = -EINVAL;
838				goto exit_f;
839			}
840
841			opt->opt_nflen += len;
842			opt->srcrt = rthdr;
843
844			if (cmsg->cmsg_type == IPV6_2292RTHDR && opt->dst1opt) {
845				int dsthdrlen = ((opt->dst1opt->hdrlen+1)<<3);
846
847				opt->opt_nflen += dsthdrlen;
848				opt->dst0opt = opt->dst1opt;
849				opt->dst1opt = NULL;
850				opt->opt_flen -= dsthdrlen;
851			}
852
853			break;
854
855		case IPV6_2292HOPLIMIT:
856		case IPV6_HOPLIMIT:
857			if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
858				err = -EINVAL;
859				goto exit_f;
860			}
861
862			*hlimit = *(int *)CMSG_DATA(cmsg);
863			if (*hlimit < -1 || *hlimit > 0xff) {
864				err = -EINVAL;
865				goto exit_f;
866			}
867
868			break;
869
870		case IPV6_TCLASS:
871		    {
872			int tc;
873
874			err = -EINVAL;
875			if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
876				goto exit_f;
877
878			tc = *(int *)CMSG_DATA(cmsg);
879			if (tc < -1 || tc > 0xff)
880				goto exit_f;
881
882			err = 0;
883			*tclass = tc;
884
885			break;
886		    }
887
888		case IPV6_DONTFRAG:
889		    {
890			int df;
891
892			err = -EINVAL;
893			if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
894				goto exit_f;
895
896			df = *(int *)CMSG_DATA(cmsg);
897			if (df < 0 || df > 1)
898				goto exit_f;
899
900			err = 0;
901			*dontfrag = df;
902
903			break;
904		    }
905		default:
906			LIMIT_NETDEBUG(KERN_DEBUG "invalid cmsg type: %d\n",
907				       cmsg->cmsg_type);
908			err = -EINVAL;
909			goto exit_f;
910		}
911	}
912
913exit_f:
914	return err;
915}
916EXPORT_SYMBOL_GPL(ip6_datagram_send_ctl);
917
918void ip6_dgram_sock_seq_show(struct seq_file *seq, struct sock *sp,
919			     __u16 srcp, __u16 destp, int bucket)
920{
921	const struct in6_addr *dest, *src;
922
923	dest  = &sp->sk_v6_daddr;
924	src   = &sp->sk_v6_rcv_saddr;
925	seq_printf(seq,
926		   "%5d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
927		   "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %d\n",
928		   bucket,
929		   src->s6_addr32[0], src->s6_addr32[1],
930		   src->s6_addr32[2], src->s6_addr32[3], srcp,
931		   dest->s6_addr32[0], dest->s6_addr32[1],
932		   dest->s6_addr32[2], dest->s6_addr32[3], destp,
933		   sp->sk_state,
934		   sk_wmem_alloc_get(sp),
935		   sk_rmem_alloc_get(sp),
936		   0, 0L, 0,
937		   from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)),
938		   0,
939		   sock_i_ino(sp),
940		   atomic_read(&sp->sk_refcnt), sp,
941		   atomic_read(&sp->sk_drops));
942}
v4.17
   1/*
   2 *	common UDP/RAW code
   3 *	Linux INET6 implementation
   4 *
   5 *	Authors:
   6 *	Pedro Roque		<roque@di.fc.ul.pt>
   7 *
   8 *	This program is free software; you can redistribute it and/or
   9 *      modify it under the terms of the GNU General Public License
  10 *      as published by the Free Software Foundation; either version
  11 *      2 of the License, or (at your option) any later version.
  12 */
  13
  14#include <linux/capability.h>
  15#include <linux/errno.h>
  16#include <linux/types.h>
  17#include <linux/kernel.h>
  18#include <linux/interrupt.h>
  19#include <linux/socket.h>
  20#include <linux/sockios.h>
  21#include <linux/in6.h>
  22#include <linux/ipv6.h>
  23#include <linux/route.h>
  24#include <linux/slab.h>
  25#include <linux/export.h>
  26
  27#include <net/ipv6.h>
  28#include <net/ndisc.h>
  29#include <net/addrconf.h>
  30#include <net/transp_v6.h>
  31#include <net/ip6_route.h>
  32#include <net/tcp_states.h>
  33#include <net/dsfield.h>
  34
  35#include <linux/errqueue.h>
  36#include <linux/uaccess.h>
  37
  38static bool ipv6_mapped_addr_any(const struct in6_addr *a)
  39{
  40	return ipv6_addr_v4mapped(a) && (a->s6_addr32[3] == 0);
  41}
  42
  43static void ip6_datagram_flow_key_init(struct flowi6 *fl6, struct sock *sk)
  44{
  45	struct inet_sock *inet = inet_sk(sk);
  46	struct ipv6_pinfo *np = inet6_sk(sk);
  47
  48	memset(fl6, 0, sizeof(*fl6));
  49	fl6->flowi6_proto = sk->sk_protocol;
  50	fl6->daddr = sk->sk_v6_daddr;
  51	fl6->saddr = np->saddr;
  52	fl6->flowi6_oif = sk->sk_bound_dev_if;
  53	fl6->flowi6_mark = sk->sk_mark;
  54	fl6->fl6_dport = inet->inet_dport;
  55	fl6->fl6_sport = inet->inet_sport;
  56	fl6->flowlabel = np->flow_label;
  57	fl6->flowi6_uid = sk->sk_uid;
  58
  59	if (!fl6->flowi6_oif)
  60		fl6->flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
  61
  62	if (!fl6->flowi6_oif && ipv6_addr_is_multicast(&fl6->daddr))
  63		fl6->flowi6_oif = np->mcast_oif;
  64
  65	security_sk_classify_flow(sk, flowi6_to_flowi(fl6));
  66}
  67
  68int ip6_datagram_dst_update(struct sock *sk, bool fix_sk_saddr)
  69{
  70	struct ip6_flowlabel *flowlabel = NULL;
  71	struct in6_addr *final_p, final;
  72	struct ipv6_txoptions *opt;
  73	struct dst_entry *dst;
  74	struct inet_sock *inet = inet_sk(sk);
  75	struct ipv6_pinfo *np = inet6_sk(sk);
  76	struct flowi6 fl6;
  77	int err = 0;
  78
  79	if (np->sndflow && (np->flow_label & IPV6_FLOWLABEL_MASK)) {
  80		flowlabel = fl6_sock_lookup(sk, np->flow_label);
  81		if (!flowlabel)
  82			return -EINVAL;
  83	}
  84	ip6_datagram_flow_key_init(&fl6, sk);
  85
  86	rcu_read_lock();
  87	opt = flowlabel ? flowlabel->opt : rcu_dereference(np->opt);
  88	final_p = fl6_update_dst(&fl6, opt, &final);
  89	rcu_read_unlock();
  90
  91	dst = ip6_dst_lookup_flow(sk, &fl6, final_p);
  92	if (IS_ERR(dst)) {
  93		err = PTR_ERR(dst);
  94		goto out;
  95	}
  96
  97	if (fix_sk_saddr) {
  98		if (ipv6_addr_any(&np->saddr))
  99			np->saddr = fl6.saddr;
 100
 101		if (ipv6_addr_any(&sk->sk_v6_rcv_saddr)) {
 102			sk->sk_v6_rcv_saddr = fl6.saddr;
 103			inet->inet_rcv_saddr = LOOPBACK4_IPV6;
 104			if (sk->sk_prot->rehash)
 105				sk->sk_prot->rehash(sk);
 106		}
 107	}
 108
 109	ip6_sk_dst_store_flow(sk, dst, &fl6);
 110
 111out:
 112	fl6_sock_release(flowlabel);
 113	return err;
 114}
 115
 116void ip6_datagram_release_cb(struct sock *sk)
 117{
 118	struct dst_entry *dst;
 119
 120	if (ipv6_addr_v4mapped(&sk->sk_v6_daddr))
 121		return;
 122
 123	rcu_read_lock();
 124	dst = __sk_dst_get(sk);
 125	if (!dst || !dst->obsolete ||
 126	    dst->ops->check(dst, inet6_sk(sk)->dst_cookie)) {
 127		rcu_read_unlock();
 128		return;
 129	}
 130	rcu_read_unlock();
 131
 132	ip6_datagram_dst_update(sk, false);
 133}
 134EXPORT_SYMBOL_GPL(ip6_datagram_release_cb);
 135
 136int __ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr,
 137			   int addr_len)
 138{
 139	struct sockaddr_in6	*usin = (struct sockaddr_in6 *) uaddr;
 140	struct inet_sock	*inet = inet_sk(sk);
 141	struct ipv6_pinfo	*np = inet6_sk(sk);
 142	struct in6_addr		*daddr, old_daddr;
 143	__be32			fl6_flowlabel = 0;
 144	__be32			old_fl6_flowlabel;
 145	__be16			old_dport;
 
 146	int			addr_type;
 147	int			err;
 148
 149	if (usin->sin6_family == AF_INET) {
 150		if (__ipv6_only_sock(sk))
 151			return -EAFNOSUPPORT;
 152		err = __ip4_datagram_connect(sk, uaddr, addr_len);
 153		goto ipv4_connected;
 154	}
 155
 156	if (addr_len < SIN6_LEN_RFC2133)
 157		return -EINVAL;
 158
 159	if (usin->sin6_family != AF_INET6)
 160		return -EAFNOSUPPORT;
 161
 162	if (np->sndflow)
 163		fl6_flowlabel = usin->sin6_flowinfo & IPV6_FLOWINFO_MASK;
 
 
 
 
 
 
 
 
 
 164
 165	if (ipv6_addr_any(&usin->sin6_addr)) {
 166		/*
 167		 *	connect to self
 168		 */
 169		if (ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr))
 170			ipv6_addr_set_v4mapped(htonl(INADDR_LOOPBACK),
 171					       &usin->sin6_addr);
 172		else
 173			usin->sin6_addr = in6addr_loopback;
 174	}
 175
 176	addr_type = ipv6_addr_type(&usin->sin6_addr);
 177
 178	daddr = &usin->sin6_addr;
 179
 180	if (addr_type & IPV6_ADDR_MAPPED) {
 181		struct sockaddr_in sin;
 182
 183		if (__ipv6_only_sock(sk)) {
 184			err = -ENETUNREACH;
 185			goto out;
 186		}
 187		sin.sin_family = AF_INET;
 188		sin.sin_addr.s_addr = daddr->s6_addr32[3];
 189		sin.sin_port = usin->sin6_port;
 190
 191		err = __ip4_datagram_connect(sk,
 192					     (struct sockaddr *) &sin,
 193					     sizeof(sin));
 194
 195ipv4_connected:
 196		if (err)
 197			goto out;
 198
 199		ipv6_addr_set_v4mapped(inet->inet_daddr, &sk->sk_v6_daddr);
 200
 201		if (ipv6_addr_any(&np->saddr) ||
 202		    ipv6_mapped_addr_any(&np->saddr))
 203			ipv6_addr_set_v4mapped(inet->inet_saddr, &np->saddr);
 204
 205		if (ipv6_addr_any(&sk->sk_v6_rcv_saddr) ||
 206		    ipv6_mapped_addr_any(&sk->sk_v6_rcv_saddr)) {
 207			ipv6_addr_set_v4mapped(inet->inet_rcv_saddr,
 208					       &sk->sk_v6_rcv_saddr);
 209			if (sk->sk_prot->rehash)
 210				sk->sk_prot->rehash(sk);
 211		}
 212
 213		goto out;
 214	}
 215
 216	if (__ipv6_addr_needs_scope_id(addr_type)) {
 217		if (addr_len >= sizeof(struct sockaddr_in6) &&
 218		    usin->sin6_scope_id) {
 219			if (!sk_dev_equal_l3scope(sk, usin->sin6_scope_id)) {
 
 220				err = -EINVAL;
 221				goto out;
 222			}
 223			sk->sk_bound_dev_if = usin->sin6_scope_id;
 224		}
 225
 226		if (!sk->sk_bound_dev_if && (addr_type & IPV6_ADDR_MULTICAST))
 227			sk->sk_bound_dev_if = np->mcast_oif;
 228
 229		/* Connect to link-local address requires an interface */
 230		if (!sk->sk_bound_dev_if) {
 231			err = -EINVAL;
 232			goto out;
 233		}
 234	}
 235
 236	/* save the current peer information before updating it */
 237	old_daddr = sk->sk_v6_daddr;
 238	old_fl6_flowlabel = np->flow_label;
 239	old_dport = inet->inet_dport;
 240
 241	sk->sk_v6_daddr = *daddr;
 242	np->flow_label = fl6_flowlabel;
 243	inet->inet_dport = usin->sin6_port;
 244
 245	/*
 246	 *	Check for a route to destination an obtain the
 247	 *	destination cache for it.
 248	 */
 249
 250	err = ip6_datagram_dst_update(sk, true);
 251	if (err) {
 252		/* Restore the socket peer info, to keep it consistent with
 253		 * the old socket state
 254		 */
 255		sk->sk_v6_daddr = old_daddr;
 256		np->flow_label = old_fl6_flowlabel;
 257		inet->inet_dport = old_dport;
 
 
 
 
 
 
 
 
 
 
 
 
 258		goto out;
 259	}
 260
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 261	sk->sk_state = TCP_ESTABLISHED;
 262	sk_set_txhash(sk);
 263out:
 
 264	return err;
 265}
 266EXPORT_SYMBOL_GPL(__ip6_datagram_connect);
 267
 268int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 269{
 270	int res;
 271
 272	lock_sock(sk);
 273	res = __ip6_datagram_connect(sk, uaddr, addr_len);
 274	release_sock(sk);
 275	return res;
 276}
 277EXPORT_SYMBOL_GPL(ip6_datagram_connect);
 278
 279int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *uaddr,
 280				 int addr_len)
 281{
 282	DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, uaddr);
 283	if (sin6->sin6_family != AF_INET6)
 284		return -EAFNOSUPPORT;
 285	return ip6_datagram_connect(sk, uaddr, addr_len);
 286}
 287EXPORT_SYMBOL_GPL(ip6_datagram_connect_v6_only);
 288
 289void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
 290		     __be16 port, u32 info, u8 *payload)
 291{
 292	struct ipv6_pinfo *np  = inet6_sk(sk);
 293	struct icmp6hdr *icmph = icmp6_hdr(skb);
 294	struct sock_exterr_skb *serr;
 295
 296	if (!np->recverr)
 297		return;
 298
 299	skb = skb_clone(skb, GFP_ATOMIC);
 300	if (!skb)
 301		return;
 302
 303	skb->protocol = htons(ETH_P_IPV6);
 304
 305	serr = SKB_EXT_ERR(skb);
 306	serr->ee.ee_errno = err;
 307	serr->ee.ee_origin = SO_EE_ORIGIN_ICMP6;
 308	serr->ee.ee_type = icmph->icmp6_type;
 309	serr->ee.ee_code = icmph->icmp6_code;
 310	serr->ee.ee_pad = 0;
 311	serr->ee.ee_info = info;
 312	serr->ee.ee_data = 0;
 313	serr->addr_offset = (u8 *)&(((struct ipv6hdr *)(icmph + 1))->daddr) -
 314				  skb_network_header(skb);
 315	serr->port = port;
 316
 317	__skb_pull(skb, payload - skb->data);
 318	skb_reset_transport_header(skb);
 319
 320	if (sock_queue_err_skb(sk, skb))
 321		kfree_skb(skb);
 322}
 323
 324void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info)
 325{
 326	const struct ipv6_pinfo *np = inet6_sk(sk);
 327	struct sock_exterr_skb *serr;
 328	struct ipv6hdr *iph;
 329	struct sk_buff *skb;
 330
 331	if (!np->recverr)
 332		return;
 333
 334	skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
 335	if (!skb)
 336		return;
 337
 338	skb->protocol = htons(ETH_P_IPV6);
 339
 340	skb_put(skb, sizeof(struct ipv6hdr));
 341	skb_reset_network_header(skb);
 342	iph = ipv6_hdr(skb);
 343	iph->daddr = fl6->daddr;
 344
 345	serr = SKB_EXT_ERR(skb);
 346	serr->ee.ee_errno = err;
 347	serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
 348	serr->ee.ee_type = 0;
 349	serr->ee.ee_code = 0;
 350	serr->ee.ee_pad = 0;
 351	serr->ee.ee_info = info;
 352	serr->ee.ee_data = 0;
 353	serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
 354	serr->port = fl6->fl6_dport;
 355
 356	__skb_pull(skb, skb_tail_pointer(skb) - skb->data);
 357	skb_reset_transport_header(skb);
 358
 359	if (sock_queue_err_skb(sk, skb))
 360		kfree_skb(skb);
 361}
 362
 363void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu)
 364{
 365	struct ipv6_pinfo *np = inet6_sk(sk);
 366	struct ipv6hdr *iph;
 367	struct sk_buff *skb;
 368	struct ip6_mtuinfo *mtu_info;
 369
 370	if (!np->rxopt.bits.rxpmtu)
 371		return;
 372
 373	skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
 374	if (!skb)
 375		return;
 376
 377	skb_put(skb, sizeof(struct ipv6hdr));
 378	skb_reset_network_header(skb);
 379	iph = ipv6_hdr(skb);
 380	iph->daddr = fl6->daddr;
 381
 382	mtu_info = IP6CBMTU(skb);
 383
 384	mtu_info->ip6m_mtu = mtu;
 385	mtu_info->ip6m_addr.sin6_family = AF_INET6;
 386	mtu_info->ip6m_addr.sin6_port = 0;
 387	mtu_info->ip6m_addr.sin6_flowinfo = 0;
 388	mtu_info->ip6m_addr.sin6_scope_id = fl6->flowi6_oif;
 389	mtu_info->ip6m_addr.sin6_addr = ipv6_hdr(skb)->daddr;
 390
 391	__skb_pull(skb, skb_tail_pointer(skb) - skb->data);
 392	skb_reset_transport_header(skb);
 393
 394	skb = xchg(&np->rxpmtu, skb);
 395	kfree_skb(skb);
 396}
 397
 398/* For some errors we have valid addr_offset even with zero payload and
 399 * zero port. Also, addr_offset should be supported if port is set.
 400 */
 401static inline bool ipv6_datagram_support_addr(struct sock_exterr_skb *serr)
 402{
 403	return serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6 ||
 404	       serr->ee.ee_origin == SO_EE_ORIGIN_ICMP ||
 405	       serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL || serr->port;
 406}
 407
 408/* IPv6 supports cmsg on all origins aside from SO_EE_ORIGIN_LOCAL.
 409 *
 410 * At one point, excluding local errors was a quick test to identify icmp/icmp6
 411 * errors. This is no longer true, but the test remained, so the v6 stack,
 412 * unlike v4, also honors cmsg requests on all wifi and timestamp errors.
 413 */
 414static bool ip6_datagram_support_cmsg(struct sk_buff *skb,
 415				      struct sock_exterr_skb *serr)
 416{
 417	if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP ||
 418	    serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6)
 419		return true;
 420
 421	if (serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL)
 422		return false;
 423
 424	if (!IP6CB(skb)->iif)
 425		return false;
 426
 427	return true;
 428}
 429
 430/*
 431 *	Handle MSG_ERRQUEUE
 432 */
 433int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
 434{
 435	struct ipv6_pinfo *np = inet6_sk(sk);
 436	struct sock_exterr_skb *serr;
 437	struct sk_buff *skb;
 438	DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name);
 439	struct {
 440		struct sock_extended_err ee;
 441		struct sockaddr_in6	 offender;
 442	} errhdr;
 443	int err;
 444	int copied;
 445
 446	err = -EAGAIN;
 447	skb = sock_dequeue_err_skb(sk);
 448	if (!skb)
 449		goto out;
 450
 451	copied = skb->len;
 452	if (copied > len) {
 453		msg->msg_flags |= MSG_TRUNC;
 454		copied = len;
 455	}
 456	err = skb_copy_datagram_msg(skb, 0, msg, copied);
 457	if (unlikely(err)) {
 458		kfree_skb(skb);
 459		return err;
 460	}
 461	sock_recv_timestamp(msg, sk, skb);
 462
 463	serr = SKB_EXT_ERR(skb);
 464
 465	if (sin && ipv6_datagram_support_addr(serr)) {
 466		const unsigned char *nh = skb_network_header(skb);
 467		sin->sin6_family = AF_INET6;
 468		sin->sin6_flowinfo = 0;
 469		sin->sin6_port = serr->port;
 470		if (skb->protocol == htons(ETH_P_IPV6)) {
 471			const struct ipv6hdr *ip6h = container_of((struct in6_addr *)(nh + serr->addr_offset),
 472								  struct ipv6hdr, daddr);
 473			sin->sin6_addr = ip6h->daddr;
 474			if (np->sndflow)
 475				sin->sin6_flowinfo = ip6_flowinfo(ip6h);
 476			sin->sin6_scope_id =
 477				ipv6_iface_scope_id(&sin->sin6_addr,
 478						    IP6CB(skb)->iif);
 479		} else {
 480			ipv6_addr_set_v4mapped(*(__be32 *)(nh + serr->addr_offset),
 481					       &sin->sin6_addr);
 482			sin->sin6_scope_id = 0;
 483		}
 484		*addr_len = sizeof(*sin);
 485	}
 486
 487	memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
 488	sin = &errhdr.offender;
 489	memset(sin, 0, sizeof(*sin));
 490
 491	if (ip6_datagram_support_cmsg(skb, serr)) {
 492		sin->sin6_family = AF_INET6;
 
 
 493		if (np->rxopt.all)
 494			ip6_datagram_recv_common_ctl(sk, msg, skb);
 495		if (skb->protocol == htons(ETH_P_IPV6)) {
 496			sin->sin6_addr = ipv6_hdr(skb)->saddr;
 497			if (np->rxopt.all)
 498				ip6_datagram_recv_specific_ctl(sk, msg, skb);
 499			sin->sin6_scope_id =
 500				ipv6_iface_scope_id(&sin->sin6_addr,
 501						    IP6CB(skb)->iif);
 502		} else {
 
 
 503			ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
 504					       &sin->sin6_addr);
 505			if (inet_sk(sk)->cmsg_flags)
 
 506				ip_cmsg_recv(msg, skb);
 507		}
 508	}
 509
 510	put_cmsg(msg, SOL_IPV6, IPV6_RECVERR, sizeof(errhdr), &errhdr);
 511
 512	/* Now we could try to dump offended packet options */
 513
 514	msg->msg_flags |= MSG_ERRQUEUE;
 515	err = copied;
 516
 517	consume_skb(skb);
 
 
 
 
 
 
 
 
 
 
 
 
 518out:
 519	return err;
 520}
 521EXPORT_SYMBOL_GPL(ipv6_recv_error);
 522
 523/*
 524 *	Handle IPV6_RECVPATHMTU
 525 */
 526int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len,
 527		     int *addr_len)
 528{
 529	struct ipv6_pinfo *np = inet6_sk(sk);
 530	struct sk_buff *skb;
 531	struct ip6_mtuinfo mtu_info;
 532	DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name);
 533	int err;
 534	int copied;
 535
 536	err = -EAGAIN;
 537	skb = xchg(&np->rxpmtu, NULL);
 538	if (!skb)
 539		goto out;
 540
 541	copied = skb->len;
 542	if (copied > len) {
 543		msg->msg_flags |= MSG_TRUNC;
 544		copied = len;
 545	}
 546	err = skb_copy_datagram_msg(skb, 0, msg, copied);
 547	if (err)
 548		goto out_free_skb;
 549
 550	sock_recv_timestamp(msg, sk, skb);
 551
 552	memcpy(&mtu_info, IP6CBMTU(skb), sizeof(mtu_info));
 553
 554	if (sin) {
 555		sin->sin6_family = AF_INET6;
 556		sin->sin6_flowinfo = 0;
 557		sin->sin6_port = 0;
 558		sin->sin6_scope_id = mtu_info.ip6m_addr.sin6_scope_id;
 559		sin->sin6_addr = mtu_info.ip6m_addr.sin6_addr;
 560		*addr_len = sizeof(*sin);
 561	}
 562
 563	put_cmsg(msg, SOL_IPV6, IPV6_PATHMTU, sizeof(mtu_info), &mtu_info);
 564
 565	err = copied;
 566
 567out_free_skb:
 568	kfree_skb(skb);
 569out:
 570	return err;
 571}
 572
 573
 574void ip6_datagram_recv_common_ctl(struct sock *sk, struct msghdr *msg,
 575				 struct sk_buff *skb)
 576{
 577	struct ipv6_pinfo *np = inet6_sk(sk);
 578	bool is_ipv6 = skb->protocol == htons(ETH_P_IPV6);
 579
 580	if (np->rxopt.bits.rxinfo) {
 581		struct in6_pktinfo src_info;
 582
 583		if (is_ipv6) {
 584			src_info.ipi6_ifindex = IP6CB(skb)->iif;
 585			src_info.ipi6_addr = ipv6_hdr(skb)->daddr;
 586		} else {
 587			src_info.ipi6_ifindex =
 588				PKTINFO_SKB_CB(skb)->ipi_ifindex;
 589			ipv6_addr_set_v4mapped(ip_hdr(skb)->daddr,
 590					       &src_info.ipi6_addr);
 591		}
 592
 593		if (src_info.ipi6_ifindex >= 0)
 594			put_cmsg(msg, SOL_IPV6, IPV6_PKTINFO,
 595				 sizeof(src_info), &src_info);
 596	}
 597}
 598
 599void ip6_datagram_recv_specific_ctl(struct sock *sk, struct msghdr *msg,
 600				    struct sk_buff *skb)
 601{
 602	struct ipv6_pinfo *np = inet6_sk(sk);
 603	struct inet6_skb_parm *opt = IP6CB(skb);
 604	unsigned char *nh = skb_network_header(skb);
 605
 606	if (np->rxopt.bits.rxhlim) {
 607		int hlim = ipv6_hdr(skb)->hop_limit;
 608		put_cmsg(msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
 609	}
 610
 611	if (np->rxopt.bits.rxtclass) {
 612		int tclass = ipv6_get_dsfield(ipv6_hdr(skb));
 613		put_cmsg(msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
 614	}
 615
 616	if (np->rxopt.bits.rxflow) {
 617		__be32 flowinfo = ip6_flowinfo((struct ipv6hdr *)nh);
 618		if (flowinfo)
 619			put_cmsg(msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
 620	}
 621
 622	/* HbH is allowed only once */
 623	if (np->rxopt.bits.hopopts && (opt->flags & IP6SKB_HOPBYHOP)) {
 624		u8 *ptr = nh + sizeof(struct ipv6hdr);
 625		put_cmsg(msg, SOL_IPV6, IPV6_HOPOPTS, (ptr[1]+1)<<3, ptr);
 626	}
 627
 628	if (opt->lastopt &&
 629	    (np->rxopt.bits.dstopts || np->rxopt.bits.srcrt)) {
 630		/*
 631		 * Silly enough, but we need to reparse in order to
 632		 * report extension headers (except for HbH)
 633		 * in order.
 634		 *
 635		 * Also note that IPV6_RECVRTHDRDSTOPTS is NOT
 636		 * (and WILL NOT be) defined because
 637		 * IPV6_RECVDSTOPTS is more generic. --yoshfuji
 638		 */
 639		unsigned int off = sizeof(struct ipv6hdr);
 640		u8 nexthdr = ipv6_hdr(skb)->nexthdr;
 641
 642		while (off <= opt->lastopt) {
 643			unsigned int len;
 644			u8 *ptr = nh + off;
 645
 646			switch (nexthdr) {
 647			case IPPROTO_DSTOPTS:
 648				nexthdr = ptr[0];
 649				len = (ptr[1] + 1) << 3;
 650				if (np->rxopt.bits.dstopts)
 651					put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, len, ptr);
 652				break;
 653			case IPPROTO_ROUTING:
 654				nexthdr = ptr[0];
 655				len = (ptr[1] + 1) << 3;
 656				if (np->rxopt.bits.srcrt)
 657					put_cmsg(msg, SOL_IPV6, IPV6_RTHDR, len, ptr);
 658				break;
 659			case IPPROTO_AH:
 660				nexthdr = ptr[0];
 661				len = (ptr[1] + 2) << 2;
 662				break;
 663			default:
 664				nexthdr = ptr[0];
 665				len = (ptr[1] + 1) << 3;
 666				break;
 667			}
 668
 669			off += len;
 670		}
 671	}
 672
 673	/* socket options in old style */
 674	if (np->rxopt.bits.rxoinfo) {
 675		struct in6_pktinfo src_info;
 676
 677		src_info.ipi6_ifindex = opt->iif;
 678		src_info.ipi6_addr = ipv6_hdr(skb)->daddr;
 679		put_cmsg(msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
 680	}
 681	if (np->rxopt.bits.rxohlim) {
 682		int hlim = ipv6_hdr(skb)->hop_limit;
 683		put_cmsg(msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
 684	}
 685	if (np->rxopt.bits.ohopopts && (opt->flags & IP6SKB_HOPBYHOP)) {
 686		u8 *ptr = nh + sizeof(struct ipv6hdr);
 687		put_cmsg(msg, SOL_IPV6, IPV6_2292HOPOPTS, (ptr[1]+1)<<3, ptr);
 688	}
 689	if (np->rxopt.bits.odstopts && opt->dst0) {
 690		u8 *ptr = nh + opt->dst0;
 691		put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
 692	}
 693	if (np->rxopt.bits.osrcrt && opt->srcrt) {
 694		struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(nh + opt->srcrt);
 695		put_cmsg(msg, SOL_IPV6, IPV6_2292RTHDR, (rthdr->hdrlen+1) << 3, rthdr);
 696	}
 697	if (np->rxopt.bits.odstopts && opt->dst1) {
 698		u8 *ptr = nh + opt->dst1;
 699		put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
 700	}
 701	if (np->rxopt.bits.rxorigdstaddr) {
 702		struct sockaddr_in6 sin6;
 703		__be16 *ports = (__be16 *) skb_transport_header(skb);
 704
 705		if (skb_transport_offset(skb) + 4 <= (int)skb->len) {
 706			/* All current transport protocols have the port numbers in the
 707			 * first four bytes of the transport header and this function is
 708			 * written with this assumption in mind.
 709			 */
 710
 711			sin6.sin6_family = AF_INET6;
 712			sin6.sin6_addr = ipv6_hdr(skb)->daddr;
 713			sin6.sin6_port = ports[1];
 714			sin6.sin6_flowinfo = 0;
 715			sin6.sin6_scope_id =
 716				ipv6_iface_scope_id(&ipv6_hdr(skb)->daddr,
 717						    opt->iif);
 718
 719			put_cmsg(msg, SOL_IPV6, IPV6_ORIGDSTADDR, sizeof(sin6), &sin6);
 720		}
 721	}
 722	if (np->rxopt.bits.recvfragsize && opt->frag_max_size) {
 723		int val = opt->frag_max_size;
 724
 725		put_cmsg(msg, SOL_IPV6, IPV6_RECVFRAGSIZE, sizeof(val), &val);
 726	}
 727}
 728
 729void ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg,
 730			  struct sk_buff *skb)
 731{
 732	ip6_datagram_recv_common_ctl(sk, msg, skb);
 733	ip6_datagram_recv_specific_ctl(sk, msg, skb);
 734}
 735EXPORT_SYMBOL_GPL(ip6_datagram_recv_ctl);
 736
 737int ip6_datagram_send_ctl(struct net *net, struct sock *sk,
 738			  struct msghdr *msg, struct flowi6 *fl6,
 739			  struct ipcm6_cookie *ipc6, struct sockcm_cookie *sockc)
 
 740{
 741	struct in6_pktinfo *src_info;
 742	struct cmsghdr *cmsg;
 743	struct ipv6_rt_hdr *rthdr;
 744	struct ipv6_opt_hdr *hdr;
 745	struct ipv6_txoptions *opt = ipc6->opt;
 746	int len;
 747	int err = 0;
 748
 749	for_each_cmsghdr(cmsg, msg) {
 750		int addr_type;
 751
 752		if (!CMSG_OK(msg, cmsg)) {
 753			err = -EINVAL;
 754			goto exit_f;
 755		}
 756
 757		if (cmsg->cmsg_level == SOL_SOCKET) {
 758			err = __sock_cmsg_send(sk, msg, cmsg, sockc);
 759			if (err)
 760				return err;
 761			continue;
 762		}
 763
 764		if (cmsg->cmsg_level != SOL_IPV6)
 765			continue;
 766
 767		switch (cmsg->cmsg_type) {
 768		case IPV6_PKTINFO:
 769		case IPV6_2292PKTINFO:
 770		    {
 771			struct net_device *dev = NULL;
 772
 773			if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct in6_pktinfo))) {
 774				err = -EINVAL;
 775				goto exit_f;
 776			}
 777
 778			src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
 779
 780			if (src_info->ipi6_ifindex) {
 781				if (fl6->flowi6_oif &&
 782				    src_info->ipi6_ifindex != fl6->flowi6_oif)
 783					return -EINVAL;
 784				fl6->flowi6_oif = src_info->ipi6_ifindex;
 785			}
 786
 787			addr_type = __ipv6_addr_type(&src_info->ipi6_addr);
 788
 789			rcu_read_lock();
 790			if (fl6->flowi6_oif) {
 791				dev = dev_get_by_index_rcu(net, fl6->flowi6_oif);
 792				if (!dev) {
 793					rcu_read_unlock();
 794					return -ENODEV;
 795				}
 796			} else if (addr_type & IPV6_ADDR_LINKLOCAL) {
 797				rcu_read_unlock();
 798				return -EINVAL;
 799			}
 800
 801			if (addr_type != IPV6_ADDR_ANY) {
 802				int strict = __ipv6_addr_src_scope(addr_type) <= IPV6_ADDR_SCOPE_LINKLOCAL;
 803				if (!(inet_sk(sk)->freebind || inet_sk(sk)->transparent) &&
 804				    !ipv6_chk_addr_and_flags(net, &src_info->ipi6_addr,
 805							     dev, !strict, 0,
 806							     IFA_F_TENTATIVE) &&
 807				    !ipv6_chk_acast_addr_src(net, dev,
 808							     &src_info->ipi6_addr))
 809					err = -EINVAL;
 810				else
 811					fl6->saddr = src_info->ipi6_addr;
 812			}
 813
 814			rcu_read_unlock();
 815
 816			if (err)
 817				goto exit_f;
 818
 819			break;
 820		    }
 821
 822		case IPV6_FLOWINFO:
 823			if (cmsg->cmsg_len < CMSG_LEN(4)) {
 824				err = -EINVAL;
 825				goto exit_f;
 826			}
 827
 828			if (fl6->flowlabel&IPV6_FLOWINFO_MASK) {
 829				if ((fl6->flowlabel^*(__be32 *)CMSG_DATA(cmsg))&~IPV6_FLOWINFO_MASK) {
 830					err = -EINVAL;
 831					goto exit_f;
 832				}
 833			}
 834			fl6->flowlabel = IPV6_FLOWINFO_MASK & *(__be32 *)CMSG_DATA(cmsg);
 835			break;
 836
 837		case IPV6_2292HOPOPTS:
 838		case IPV6_HOPOPTS:
 839			if (opt->hopopt || cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
 840				err = -EINVAL;
 841				goto exit_f;
 842			}
 843
 844			hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
 845			len = ((hdr->hdrlen + 1) << 3);
 846			if (cmsg->cmsg_len < CMSG_LEN(len)) {
 847				err = -EINVAL;
 848				goto exit_f;
 849			}
 850			if (!ns_capable(net->user_ns, CAP_NET_RAW)) {
 851				err = -EPERM;
 852				goto exit_f;
 853			}
 854			opt->opt_nflen += len;
 855			opt->hopopt = hdr;
 856			break;
 857
 858		case IPV6_2292DSTOPTS:
 859			if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
 860				err = -EINVAL;
 861				goto exit_f;
 862			}
 863
 864			hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
 865			len = ((hdr->hdrlen + 1) << 3);
 866			if (cmsg->cmsg_len < CMSG_LEN(len)) {
 867				err = -EINVAL;
 868				goto exit_f;
 869			}
 870			if (!ns_capable(net->user_ns, CAP_NET_RAW)) {
 871				err = -EPERM;
 872				goto exit_f;
 873			}
 874			if (opt->dst1opt) {
 875				err = -EINVAL;
 876				goto exit_f;
 877			}
 878			opt->opt_flen += len;
 879			opt->dst1opt = hdr;
 880			break;
 881
 882		case IPV6_DSTOPTS:
 883		case IPV6_RTHDRDSTOPTS:
 884			if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
 885				err = -EINVAL;
 886				goto exit_f;
 887			}
 888
 889			hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
 890			len = ((hdr->hdrlen + 1) << 3);
 891			if (cmsg->cmsg_len < CMSG_LEN(len)) {
 892				err = -EINVAL;
 893				goto exit_f;
 894			}
 895			if (!ns_capable(net->user_ns, CAP_NET_RAW)) {
 896				err = -EPERM;
 897				goto exit_f;
 898			}
 899			if (cmsg->cmsg_type == IPV6_DSTOPTS) {
 900				opt->opt_flen += len;
 901				opt->dst1opt = hdr;
 902			} else {
 903				opt->opt_nflen += len;
 904				opt->dst0opt = hdr;
 905			}
 906			break;
 907
 908		case IPV6_2292RTHDR:
 909		case IPV6_RTHDR:
 910			if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_rt_hdr))) {
 911				err = -EINVAL;
 912				goto exit_f;
 913			}
 914
 915			rthdr = (struct ipv6_rt_hdr *)CMSG_DATA(cmsg);
 916
 917			switch (rthdr->type) {
 918#if IS_ENABLED(CONFIG_IPV6_MIP6)
 919			case IPV6_SRCRT_TYPE_2:
 920				if (rthdr->hdrlen != 2 ||
 921				    rthdr->segments_left != 1) {
 922					err = -EINVAL;
 923					goto exit_f;
 924				}
 925				break;
 926#endif
 927			default:
 928				err = -EINVAL;
 929				goto exit_f;
 930			}
 931
 932			len = ((rthdr->hdrlen + 1) << 3);
 933
 934			if (cmsg->cmsg_len < CMSG_LEN(len)) {
 935				err = -EINVAL;
 936				goto exit_f;
 937			}
 938
 939			/* segments left must also match */
 940			if ((rthdr->hdrlen >> 1) != rthdr->segments_left) {
 941				err = -EINVAL;
 942				goto exit_f;
 943			}
 944
 945			opt->opt_nflen += len;
 946			opt->srcrt = rthdr;
 947
 948			if (cmsg->cmsg_type == IPV6_2292RTHDR && opt->dst1opt) {
 949				int dsthdrlen = ((opt->dst1opt->hdrlen+1)<<3);
 950
 951				opt->opt_nflen += dsthdrlen;
 952				opt->dst0opt = opt->dst1opt;
 953				opt->dst1opt = NULL;
 954				opt->opt_flen -= dsthdrlen;
 955			}
 956
 957			break;
 958
 959		case IPV6_2292HOPLIMIT:
 960		case IPV6_HOPLIMIT:
 961			if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
 962				err = -EINVAL;
 963				goto exit_f;
 964			}
 965
 966			ipc6->hlimit = *(int *)CMSG_DATA(cmsg);
 967			if (ipc6->hlimit < -1 || ipc6->hlimit > 0xff) {
 968				err = -EINVAL;
 969				goto exit_f;
 970			}
 971
 972			break;
 973
 974		case IPV6_TCLASS:
 975		    {
 976			int tc;
 977
 978			err = -EINVAL;
 979			if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
 980				goto exit_f;
 981
 982			tc = *(int *)CMSG_DATA(cmsg);
 983			if (tc < -1 || tc > 0xff)
 984				goto exit_f;
 985
 986			err = 0;
 987			ipc6->tclass = tc;
 988
 989			break;
 990		    }
 991
 992		case IPV6_DONTFRAG:
 993		    {
 994			int df;
 995
 996			err = -EINVAL;
 997			if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
 998				goto exit_f;
 999
1000			df = *(int *)CMSG_DATA(cmsg);
1001			if (df < 0 || df > 1)
1002				goto exit_f;
1003
1004			err = 0;
1005			ipc6->dontfrag = df;
1006
1007			break;
1008		    }
1009		default:
1010			net_dbg_ratelimited("invalid cmsg type: %d\n",
1011					    cmsg->cmsg_type);
1012			err = -EINVAL;
1013			goto exit_f;
1014		}
1015	}
1016
1017exit_f:
1018	return err;
1019}
1020EXPORT_SYMBOL_GPL(ip6_datagram_send_ctl);
1021
1022void ip6_dgram_sock_seq_show(struct seq_file *seq, struct sock *sp,
1023			     __u16 srcp, __u16 destp, int bucket)
1024{
1025	const struct in6_addr *dest, *src;
1026
1027	dest  = &sp->sk_v6_daddr;
1028	src   = &sp->sk_v6_rcv_saddr;
1029	seq_printf(seq,
1030		   "%5d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
1031		   "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %d\n",
1032		   bucket,
1033		   src->s6_addr32[0], src->s6_addr32[1],
1034		   src->s6_addr32[2], src->s6_addr32[3], srcp,
1035		   dest->s6_addr32[0], dest->s6_addr32[1],
1036		   dest->s6_addr32[2], dest->s6_addr32[3], destp,
1037		   sp->sk_state,
1038		   sk_wmem_alloc_get(sp),
1039		   sk_rmem_alloc_get(sp),
1040		   0, 0L, 0,
1041		   from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)),
1042		   0,
1043		   sock_i_ino(sp),
1044		   refcount_read(&sp->sk_refcnt), sp,
1045		   atomic_read(&sp->sk_drops));
1046}