xref: /linux/net/ipv6/raw.c (revision 2da68a77)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *	RAW sockets for IPv6
4  *	Linux INET6 implementation
5  *
6  *	Authors:
7  *	Pedro Roque		<roque@di.fc.ul.pt>
8  *
9  *	Adapted from linux/net/ipv4/raw.c
10  *
11  *	Fixes:
12  *	Hideaki YOSHIFUJI	:	sin6_scope_id support
13  *	YOSHIFUJI,H.@USAGI	:	raw checksum (RFC2292(bis) compliance)
14  *	Kazunori MIYAZAWA @USAGI:	change process style to use ip6_append_data
15  */
16 
17 #include <linux/errno.h>
18 #include <linux/types.h>
19 #include <linux/socket.h>
20 #include <linux/slab.h>
21 #include <linux/sockios.h>
22 #include <linux/net.h>
23 #include <linux/in6.h>
24 #include <linux/netdevice.h>
25 #include <linux/if_arp.h>
26 #include <linux/icmpv6.h>
27 #include <linux/netfilter.h>
28 #include <linux/netfilter_ipv6.h>
29 #include <linux/skbuff.h>
30 #include <linux/compat.h>
31 #include <linux/uaccess.h>
32 #include <asm/ioctls.h>
33 
34 #include <net/net_namespace.h>
35 #include <net/ip.h>
36 #include <net/sock.h>
37 #include <net/snmp.h>
38 
39 #include <net/ipv6.h>
40 #include <net/ndisc.h>
41 #include <net/protocol.h>
42 #include <net/ip6_route.h>
43 #include <net/ip6_checksum.h>
44 #include <net/addrconf.h>
45 #include <net/transp_v6.h>
46 #include <net/udp.h>
47 #include <net/inet_common.h>
48 #include <net/tcp_states.h>
49 #if IS_ENABLED(CONFIG_IPV6_MIP6)
50 #include <net/mip6.h>
51 #endif
52 #include <linux/mroute6.h>
53 
54 #include <net/raw.h>
55 #include <net/rawv6.h>
56 #include <net/xfrm.h>
57 
58 #include <linux/proc_fs.h>
59 #include <linux/seq_file.h>
60 #include <linux/export.h>
61 
62 #define	ICMPV6_HDRLEN	4	/* ICMPv6 header, RFC 4443 Section 2.1 */
63 
64 struct raw_hashinfo raw_v6_hashinfo;
65 EXPORT_SYMBOL_GPL(raw_v6_hashinfo);
66 
67 bool raw_v6_match(struct net *net, struct sock *sk, unsigned short num,
68 		  const struct in6_addr *loc_addr,
69 		  const struct in6_addr *rmt_addr, int dif, int sdif)
70 {
71 	if (inet_sk(sk)->inet_num != num ||
72 	    !net_eq(sock_net(sk), net) ||
73 	    (!ipv6_addr_any(&sk->sk_v6_daddr) &&
74 	     !ipv6_addr_equal(&sk->sk_v6_daddr, rmt_addr)) ||
75 	    !raw_sk_bound_dev_eq(net, sk->sk_bound_dev_if,
76 				 dif, sdif))
77 		return false;
78 
79 	if (ipv6_addr_any(&sk->sk_v6_rcv_saddr) ||
80 	    ipv6_addr_equal(&sk->sk_v6_rcv_saddr, loc_addr) ||
81 	    (ipv6_addr_is_multicast(loc_addr) &&
82 	     inet6_mc_check(sk, loc_addr, rmt_addr)))
83 		return true;
84 
85 	return false;
86 }
87 EXPORT_SYMBOL_GPL(raw_v6_match);
88 
89 /*
90  *	0 - deliver
91  *	1 - block
92  */
93 static int icmpv6_filter(const struct sock *sk, const struct sk_buff *skb)
94 {
95 	struct icmp6hdr _hdr;
96 	const struct icmp6hdr *hdr;
97 
98 	/* We require only the four bytes of the ICMPv6 header, not any
99 	 * additional bytes of message body in "struct icmp6hdr".
100 	 */
101 	hdr = skb_header_pointer(skb, skb_transport_offset(skb),
102 				 ICMPV6_HDRLEN, &_hdr);
103 	if (hdr) {
104 		const __u32 *data = &raw6_sk(sk)->filter.data[0];
105 		unsigned int type = hdr->icmp6_type;
106 
107 		return (data[type >> 5] & (1U << (type & 31))) != 0;
108 	}
109 	return 1;
110 }
111 
112 #if IS_ENABLED(CONFIG_IPV6_MIP6)
113 typedef int mh_filter_t(struct sock *sock, struct sk_buff *skb);
114 
115 static mh_filter_t __rcu *mh_filter __read_mostly;
116 
117 int rawv6_mh_filter_register(mh_filter_t filter)
118 {
119 	rcu_assign_pointer(mh_filter, filter);
120 	return 0;
121 }
122 EXPORT_SYMBOL(rawv6_mh_filter_register);
123 
124 int rawv6_mh_filter_unregister(mh_filter_t filter)
125 {
126 	RCU_INIT_POINTER(mh_filter, NULL);
127 	synchronize_rcu();
128 	return 0;
129 }
130 EXPORT_SYMBOL(rawv6_mh_filter_unregister);
131 
132 #endif
133 
134 /*
135  *	demultiplex raw sockets.
136  *	(should consider queueing the skb in the sock receive_queue
137  *	without calling rawv6.c)
138  *
139  *	Caller owns SKB so we must make clones.
140  */
141 static bool ipv6_raw_deliver(struct sk_buff *skb, int nexthdr)
142 {
143 	struct net *net = dev_net(skb->dev);
144 	struct hlist_nulls_head *hlist;
145 	struct hlist_nulls_node *hnode;
146 	const struct in6_addr *saddr;
147 	const struct in6_addr *daddr;
148 	struct sock *sk;
149 	bool delivered = false;
150 	__u8 hash;
151 
152 	saddr = &ipv6_hdr(skb)->saddr;
153 	daddr = saddr + 1;
154 
155 	hash = nexthdr & (RAW_HTABLE_SIZE - 1);
156 	hlist = &raw_v6_hashinfo.ht[hash];
157 	rcu_read_lock();
158 	sk_nulls_for_each(sk, hnode, hlist) {
159 		int filtered;
160 
161 		if (!raw_v6_match(net, sk, nexthdr, daddr, saddr,
162 				  inet6_iif(skb), inet6_sdif(skb)))
163 			continue;
164 		delivered = true;
165 		switch (nexthdr) {
166 		case IPPROTO_ICMPV6:
167 			filtered = icmpv6_filter(sk, skb);
168 			break;
169 
170 #if IS_ENABLED(CONFIG_IPV6_MIP6)
171 		case IPPROTO_MH:
172 		{
173 			/* XXX: To validate MH only once for each packet,
174 			 * this is placed here. It should be after checking
175 			 * xfrm policy, however it doesn't. The checking xfrm
176 			 * policy is placed in rawv6_rcv() because it is
177 			 * required for each socket.
178 			 */
179 			mh_filter_t *filter;
180 
181 			filter = rcu_dereference(mh_filter);
182 			filtered = filter ? (*filter)(sk, skb) : 0;
183 			break;
184 		}
185 #endif
186 		default:
187 			filtered = 0;
188 			break;
189 		}
190 
191 		if (filtered < 0)
192 			break;
193 		if (filtered == 0) {
194 			struct sk_buff *clone = skb_clone(skb, GFP_ATOMIC);
195 
196 			/* Not releasing hash table! */
197 			if (clone) {
198 				nf_reset_ct(clone);
199 				rawv6_rcv(sk, clone);
200 			}
201 		}
202 	}
203 	rcu_read_unlock();
204 	return delivered;
205 }
206 
207 bool raw6_local_deliver(struct sk_buff *skb, int nexthdr)
208 {
209 	return ipv6_raw_deliver(skb, nexthdr);
210 }
211 
212 /* This cleans up af_inet6 a bit. -DaveM */
213 static int rawv6_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len)
214 {
215 	struct inet_sock *inet = inet_sk(sk);
216 	struct ipv6_pinfo *np = inet6_sk(sk);
217 	struct sockaddr_in6 *addr = (struct sockaddr_in6 *) uaddr;
218 	__be32 v4addr = 0;
219 	int addr_type;
220 	int err;
221 
222 	if (addr_len < SIN6_LEN_RFC2133)
223 		return -EINVAL;
224 
225 	if (addr->sin6_family != AF_INET6)
226 		return -EINVAL;
227 
228 	addr_type = ipv6_addr_type(&addr->sin6_addr);
229 
230 	/* Raw sockets are IPv6 only */
231 	if (addr_type == IPV6_ADDR_MAPPED)
232 		return -EADDRNOTAVAIL;
233 
234 	lock_sock(sk);
235 
236 	err = -EINVAL;
237 	if (sk->sk_state != TCP_CLOSE)
238 		goto out;
239 
240 	rcu_read_lock();
241 	/* Check if the address belongs to the host. */
242 	if (addr_type != IPV6_ADDR_ANY) {
243 		struct net_device *dev = NULL;
244 
245 		if (__ipv6_addr_needs_scope_id(addr_type)) {
246 			if (addr_len >= sizeof(struct sockaddr_in6) &&
247 			    addr->sin6_scope_id) {
248 				/* Override any existing binding, if another
249 				 * one is supplied by user.
250 				 */
251 				sk->sk_bound_dev_if = addr->sin6_scope_id;
252 			}
253 
254 			/* Binding to link-local address requires an interface */
255 			if (!sk->sk_bound_dev_if)
256 				goto out_unlock;
257 		}
258 
259 		if (sk->sk_bound_dev_if) {
260 			err = -ENODEV;
261 			dev = dev_get_by_index_rcu(sock_net(sk),
262 						   sk->sk_bound_dev_if);
263 			if (!dev)
264 				goto out_unlock;
265 		}
266 
267 		/* ipv4 addr of the socket is invalid.  Only the
268 		 * unspecified and mapped address have a v4 equivalent.
269 		 */
270 		v4addr = LOOPBACK4_IPV6;
271 		if (!(addr_type & IPV6_ADDR_MULTICAST) &&
272 		    !ipv6_can_nonlocal_bind(sock_net(sk), inet)) {
273 			err = -EADDRNOTAVAIL;
274 			if (!ipv6_chk_addr(sock_net(sk), &addr->sin6_addr,
275 					   dev, 0)) {
276 				goto out_unlock;
277 			}
278 		}
279 	}
280 
281 	inet->inet_rcv_saddr = inet->inet_saddr = v4addr;
282 	sk->sk_v6_rcv_saddr = addr->sin6_addr;
283 	if (!(addr_type & IPV6_ADDR_MULTICAST))
284 		np->saddr = addr->sin6_addr;
285 	err = 0;
286 out_unlock:
287 	rcu_read_unlock();
288 out:
289 	release_sock(sk);
290 	return err;
291 }
292 
293 static void rawv6_err(struct sock *sk, struct sk_buff *skb,
294 	       struct inet6_skb_parm *opt,
295 	       u8 type, u8 code, int offset, __be32 info)
296 {
297 	struct inet_sock *inet = inet_sk(sk);
298 	struct ipv6_pinfo *np = inet6_sk(sk);
299 	int err;
300 	int harderr;
301 
302 	/* Report error on raw socket, if:
303 	   1. User requested recverr.
304 	   2. Socket is connected (otherwise the error indication
305 	      is useless without recverr and error is hard.
306 	 */
307 	if (!np->recverr && sk->sk_state != TCP_ESTABLISHED)
308 		return;
309 
310 	harderr = icmpv6_err_convert(type, code, &err);
311 	if (type == ICMPV6_PKT_TOOBIG) {
312 		ip6_sk_update_pmtu(skb, sk, info);
313 		harderr = (np->pmtudisc == IPV6_PMTUDISC_DO);
314 	}
315 	if (type == NDISC_REDIRECT) {
316 		ip6_sk_redirect(skb, sk);
317 		return;
318 	}
319 	if (np->recverr) {
320 		u8 *payload = skb->data;
321 		if (!inet->hdrincl)
322 			payload += offset;
323 		ipv6_icmp_error(sk, skb, err, 0, ntohl(info), payload);
324 	}
325 
326 	if (np->recverr || harderr) {
327 		sk->sk_err = err;
328 		sk_error_report(sk);
329 	}
330 }
331 
332 void raw6_icmp_error(struct sk_buff *skb, int nexthdr,
333 		u8 type, u8 code, int inner_offset, __be32 info)
334 {
335 	struct net *net = dev_net(skb->dev);
336 	struct hlist_nulls_head *hlist;
337 	struct hlist_nulls_node *hnode;
338 	struct sock *sk;
339 	int hash;
340 
341 	hash = nexthdr & (RAW_HTABLE_SIZE - 1);
342 	hlist = &raw_v6_hashinfo.ht[hash];
343 	rcu_read_lock();
344 	sk_nulls_for_each(sk, hnode, hlist) {
345 		/* Note: ipv6_hdr(skb) != skb->data */
346 		const struct ipv6hdr *ip6h = (const struct ipv6hdr *)skb->data;
347 
348 		if (!raw_v6_match(net, sk, nexthdr, &ip6h->saddr, &ip6h->daddr,
349 				  inet6_iif(skb), inet6_iif(skb)))
350 			continue;
351 		rawv6_err(sk, skb, NULL, type, code, inner_offset, info);
352 	}
353 	rcu_read_unlock();
354 }
355 
356 static inline int rawv6_rcv_skb(struct sock *sk, struct sk_buff *skb)
357 {
358 	if ((raw6_sk(sk)->checksum || rcu_access_pointer(sk->sk_filter)) &&
359 	    skb_checksum_complete(skb)) {
360 		atomic_inc(&sk->sk_drops);
361 		kfree_skb(skb);
362 		return NET_RX_DROP;
363 	}
364 
365 	/* Charge it to the socket. */
366 	skb_dst_drop(skb);
367 	if (sock_queue_rcv_skb(sk, skb) < 0) {
368 		kfree_skb(skb);
369 		return NET_RX_DROP;
370 	}
371 
372 	return 0;
373 }
374 
375 /*
376  *	This is next to useless...
377  *	if we demultiplex in network layer we don't need the extra call
378  *	just to queue the skb...
379  *	maybe we could have the network decide upon a hint if it
380  *	should call raw_rcv for demultiplexing
381  */
382 int rawv6_rcv(struct sock *sk, struct sk_buff *skb)
383 {
384 	struct inet_sock *inet = inet_sk(sk);
385 	struct raw6_sock *rp = raw6_sk(sk);
386 
387 	if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) {
388 		atomic_inc(&sk->sk_drops);
389 		kfree_skb(skb);
390 		return NET_RX_DROP;
391 	}
392 
393 	if (!rp->checksum)
394 		skb->ip_summed = CHECKSUM_UNNECESSARY;
395 
396 	if (skb->ip_summed == CHECKSUM_COMPLETE) {
397 		skb_postpull_rcsum(skb, skb_network_header(skb),
398 				   skb_network_header_len(skb));
399 		if (!csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
400 				     &ipv6_hdr(skb)->daddr,
401 				     skb->len, inet->inet_num, skb->csum))
402 			skb->ip_summed = CHECKSUM_UNNECESSARY;
403 	}
404 	if (!skb_csum_unnecessary(skb))
405 		skb->csum = ~csum_unfold(csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
406 							 &ipv6_hdr(skb)->daddr,
407 							 skb->len,
408 							 inet->inet_num, 0));
409 
410 	if (inet->hdrincl) {
411 		if (skb_checksum_complete(skb)) {
412 			atomic_inc(&sk->sk_drops);
413 			kfree_skb(skb);
414 			return NET_RX_DROP;
415 		}
416 	}
417 
418 	rawv6_rcv_skb(sk, skb);
419 	return 0;
420 }
421 
422 
423 /*
424  *	This should be easy, if there is something there
425  *	we return it, otherwise we block.
426  */
427 
428 static int rawv6_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
429 			 int flags, int *addr_len)
430 {
431 	struct ipv6_pinfo *np = inet6_sk(sk);
432 	DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
433 	struct sk_buff *skb;
434 	size_t copied;
435 	int err;
436 
437 	if (flags & MSG_OOB)
438 		return -EOPNOTSUPP;
439 
440 	if (flags & MSG_ERRQUEUE)
441 		return ipv6_recv_error(sk, msg, len, addr_len);
442 
443 	if (np->rxpmtu && np->rxopt.bits.rxpmtu)
444 		return ipv6_recv_rxpmtu(sk, msg, len, addr_len);
445 
446 	skb = skb_recv_datagram(sk, flags, &err);
447 	if (!skb)
448 		goto out;
449 
450 	copied = skb->len;
451 	if (copied > len) {
452 		copied = len;
453 		msg->msg_flags |= MSG_TRUNC;
454 	}
455 
456 	if (skb_csum_unnecessary(skb)) {
457 		err = skb_copy_datagram_msg(skb, 0, msg, copied);
458 	} else if (msg->msg_flags&MSG_TRUNC) {
459 		if (__skb_checksum_complete(skb))
460 			goto csum_copy_err;
461 		err = skb_copy_datagram_msg(skb, 0, msg, copied);
462 	} else {
463 		err = skb_copy_and_csum_datagram_msg(skb, 0, msg);
464 		if (err == -EINVAL)
465 			goto csum_copy_err;
466 	}
467 	if (err)
468 		goto out_free;
469 
470 	/* Copy the address. */
471 	if (sin6) {
472 		sin6->sin6_family = AF_INET6;
473 		sin6->sin6_port = 0;
474 		sin6->sin6_addr = ipv6_hdr(skb)->saddr;
475 		sin6->sin6_flowinfo = 0;
476 		sin6->sin6_scope_id = ipv6_iface_scope_id(&sin6->sin6_addr,
477 							  inet6_iif(skb));
478 		*addr_len = sizeof(*sin6);
479 	}
480 
481 	sock_recv_cmsgs(msg, sk, skb);
482 
483 	if (np->rxopt.all)
484 		ip6_datagram_recv_ctl(sk, msg, skb);
485 
486 	err = copied;
487 	if (flags & MSG_TRUNC)
488 		err = skb->len;
489 
490 out_free:
491 	skb_free_datagram(sk, skb);
492 out:
493 	return err;
494 
495 csum_copy_err:
496 	skb_kill_datagram(sk, skb, flags);
497 
498 	/* Error for blocking case is chosen to masquerade
499 	   as some normal condition.
500 	 */
501 	err = (flags&MSG_DONTWAIT) ? -EAGAIN : -EHOSTUNREACH;
502 	goto out;
503 }
504 
505 static int rawv6_push_pending_frames(struct sock *sk, struct flowi6 *fl6,
506 				     struct raw6_sock *rp)
507 {
508 	struct sk_buff *skb;
509 	int err = 0;
510 	int offset;
511 	int len;
512 	int total_len;
513 	__wsum tmp_csum;
514 	__sum16 csum;
515 
516 	if (!rp->checksum)
517 		goto send;
518 
519 	skb = skb_peek(&sk->sk_write_queue);
520 	if (!skb)
521 		goto out;
522 
523 	offset = rp->offset;
524 	total_len = inet_sk(sk)->cork.base.length;
525 	if (offset >= total_len - 1) {
526 		err = -EINVAL;
527 		ip6_flush_pending_frames(sk);
528 		goto out;
529 	}
530 
531 	/* should be check HW csum miyazawa */
532 	if (skb_queue_len(&sk->sk_write_queue) == 1) {
533 		/*
534 		 * Only one fragment on the socket.
535 		 */
536 		tmp_csum = skb->csum;
537 	} else {
538 		struct sk_buff *csum_skb = NULL;
539 		tmp_csum = 0;
540 
541 		skb_queue_walk(&sk->sk_write_queue, skb) {
542 			tmp_csum = csum_add(tmp_csum, skb->csum);
543 
544 			if (csum_skb)
545 				continue;
546 
547 			len = skb->len - skb_transport_offset(skb);
548 			if (offset >= len) {
549 				offset -= len;
550 				continue;
551 			}
552 
553 			csum_skb = skb;
554 		}
555 
556 		skb = csum_skb;
557 	}
558 
559 	offset += skb_transport_offset(skb);
560 	err = skb_copy_bits(skb, offset, &csum, 2);
561 	if (err < 0) {
562 		ip6_flush_pending_frames(sk);
563 		goto out;
564 	}
565 
566 	/* in case cksum was not initialized */
567 	if (unlikely(csum))
568 		tmp_csum = csum_sub(tmp_csum, csum_unfold(csum));
569 
570 	csum = csum_ipv6_magic(&fl6->saddr, &fl6->daddr,
571 			       total_len, fl6->flowi6_proto, tmp_csum);
572 
573 	if (csum == 0 && fl6->flowi6_proto == IPPROTO_UDP)
574 		csum = CSUM_MANGLED_0;
575 
576 	BUG_ON(skb_store_bits(skb, offset, &csum, 2));
577 
578 send:
579 	err = ip6_push_pending_frames(sk);
580 out:
581 	return err;
582 }
583 
584 static int rawv6_send_hdrinc(struct sock *sk, struct msghdr *msg, int length,
585 			struct flowi6 *fl6, struct dst_entry **dstp,
586 			unsigned int flags, const struct sockcm_cookie *sockc)
587 {
588 	struct ipv6_pinfo *np = inet6_sk(sk);
589 	struct net *net = sock_net(sk);
590 	struct ipv6hdr *iph;
591 	struct sk_buff *skb;
592 	int err;
593 	struct rt6_info *rt = (struct rt6_info *)*dstp;
594 	int hlen = LL_RESERVED_SPACE(rt->dst.dev);
595 	int tlen = rt->dst.dev->needed_tailroom;
596 
597 	if (length > rt->dst.dev->mtu) {
598 		ipv6_local_error(sk, EMSGSIZE, fl6, rt->dst.dev->mtu);
599 		return -EMSGSIZE;
600 	}
601 	if (length < sizeof(struct ipv6hdr))
602 		return -EINVAL;
603 	if (flags&MSG_PROBE)
604 		goto out;
605 
606 	skb = sock_alloc_send_skb(sk,
607 				  length + hlen + tlen + 15,
608 				  flags & MSG_DONTWAIT, &err);
609 	if (!skb)
610 		goto error;
611 	skb_reserve(skb, hlen);
612 
613 	skb->protocol = htons(ETH_P_IPV6);
614 	skb->priority = sk->sk_priority;
615 	skb->mark = sockc->mark;
616 	skb->tstamp = sockc->transmit_time;
617 
618 	skb_put(skb, length);
619 	skb_reset_network_header(skb);
620 	iph = ipv6_hdr(skb);
621 
622 	skb->ip_summed = CHECKSUM_NONE;
623 
624 	skb_setup_tx_timestamp(skb, sockc->tsflags);
625 
626 	if (flags & MSG_CONFIRM)
627 		skb_set_dst_pending_confirm(skb, 1);
628 
629 	skb->transport_header = skb->network_header;
630 	err = memcpy_from_msg(iph, msg, length);
631 	if (err) {
632 		err = -EFAULT;
633 		kfree_skb(skb);
634 		goto error;
635 	}
636 
637 	skb_dst_set(skb, &rt->dst);
638 	*dstp = NULL;
639 
640 	/* if egress device is enslaved to an L3 master device pass the
641 	 * skb to its handler for processing
642 	 */
643 	skb = l3mdev_ip6_out(sk, skb);
644 	if (unlikely(!skb))
645 		return 0;
646 
647 	/* Acquire rcu_read_lock() in case we need to use rt->rt6i_idev
648 	 * in the error path. Since skb has been freed, the dst could
649 	 * have been queued for deletion.
650 	 */
651 	rcu_read_lock();
652 	IP6_UPD_PO_STATS(net, rt->rt6i_idev, IPSTATS_MIB_OUT, skb->len);
653 	err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT, net, sk, skb,
654 		      NULL, rt->dst.dev, dst_output);
655 	if (err > 0)
656 		err = net_xmit_errno(err);
657 	if (err) {
658 		IP6_INC_STATS(net, rt->rt6i_idev, IPSTATS_MIB_OUTDISCARDS);
659 		rcu_read_unlock();
660 		goto error_check;
661 	}
662 	rcu_read_unlock();
663 out:
664 	return 0;
665 
666 error:
667 	IP6_INC_STATS(net, rt->rt6i_idev, IPSTATS_MIB_OUTDISCARDS);
668 error_check:
669 	if (err == -ENOBUFS && !np->recverr)
670 		err = 0;
671 	return err;
672 }
673 
674 struct raw6_frag_vec {
675 	struct msghdr *msg;
676 	int hlen;
677 	char c[4];
678 };
679 
680 static int rawv6_probe_proto_opt(struct raw6_frag_vec *rfv, struct flowi6 *fl6)
681 {
682 	int err = 0;
683 	switch (fl6->flowi6_proto) {
684 	case IPPROTO_ICMPV6:
685 		rfv->hlen = 2;
686 		err = memcpy_from_msg(rfv->c, rfv->msg, rfv->hlen);
687 		if (!err) {
688 			fl6->fl6_icmp_type = rfv->c[0];
689 			fl6->fl6_icmp_code = rfv->c[1];
690 		}
691 		break;
692 	case IPPROTO_MH:
693 		rfv->hlen = 4;
694 		err = memcpy_from_msg(rfv->c, rfv->msg, rfv->hlen);
695 		if (!err)
696 			fl6->fl6_mh_type = rfv->c[2];
697 	}
698 	return err;
699 }
700 
701 static int raw6_getfrag(void *from, char *to, int offset, int len, int odd,
702 		       struct sk_buff *skb)
703 {
704 	struct raw6_frag_vec *rfv = from;
705 
706 	if (offset < rfv->hlen) {
707 		int copy = min(rfv->hlen - offset, len);
708 
709 		if (skb->ip_summed == CHECKSUM_PARTIAL)
710 			memcpy(to, rfv->c + offset, copy);
711 		else
712 			skb->csum = csum_block_add(
713 				skb->csum,
714 				csum_partial_copy_nocheck(rfv->c + offset,
715 							  to, copy),
716 				odd);
717 
718 		odd = 0;
719 		offset += copy;
720 		to += copy;
721 		len -= copy;
722 
723 		if (!len)
724 			return 0;
725 	}
726 
727 	offset -= rfv->hlen;
728 
729 	return ip_generic_getfrag(rfv->msg, to, offset, len, odd, skb);
730 }
731 
732 static int rawv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
733 {
734 	struct ipv6_txoptions *opt_to_free = NULL;
735 	struct ipv6_txoptions opt_space;
736 	DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
737 	struct in6_addr *daddr, *final_p, final;
738 	struct inet_sock *inet = inet_sk(sk);
739 	struct ipv6_pinfo *np = inet6_sk(sk);
740 	struct raw6_sock *rp = raw6_sk(sk);
741 	struct ipv6_txoptions *opt = NULL;
742 	struct ip6_flowlabel *flowlabel = NULL;
743 	struct dst_entry *dst = NULL;
744 	struct raw6_frag_vec rfv;
745 	struct flowi6 fl6;
746 	struct ipcm6_cookie ipc6;
747 	int addr_len = msg->msg_namelen;
748 	int hdrincl;
749 	u16 proto;
750 	int err;
751 
752 	/* Rough check on arithmetic overflow,
753 	   better check is made in ip6_append_data().
754 	 */
755 	if (len > INT_MAX)
756 		return -EMSGSIZE;
757 
758 	/* Mirror BSD error message compatibility */
759 	if (msg->msg_flags & MSG_OOB)
760 		return -EOPNOTSUPP;
761 
762 	/* hdrincl should be READ_ONCE(inet->hdrincl)
763 	 * but READ_ONCE() doesn't work with bit fields.
764 	 * Doing this indirectly yields the same result.
765 	 */
766 	hdrincl = inet->hdrincl;
767 	hdrincl = READ_ONCE(hdrincl);
768 
769 	/*
770 	 *	Get and verify the address.
771 	 */
772 	memset(&fl6, 0, sizeof(fl6));
773 
774 	fl6.flowi6_mark = sk->sk_mark;
775 	fl6.flowi6_uid = sk->sk_uid;
776 
777 	ipcm6_init(&ipc6);
778 	ipc6.sockc.tsflags = sk->sk_tsflags;
779 	ipc6.sockc.mark = sk->sk_mark;
780 
781 	if (sin6) {
782 		if (addr_len < SIN6_LEN_RFC2133)
783 			return -EINVAL;
784 
785 		if (sin6->sin6_family && sin6->sin6_family != AF_INET6)
786 			return -EAFNOSUPPORT;
787 
788 		/* port is the proto value [0..255] carried in nexthdr */
789 		proto = ntohs(sin6->sin6_port);
790 
791 		if (!proto)
792 			proto = inet->inet_num;
793 		else if (proto != inet->inet_num)
794 			return -EINVAL;
795 
796 		if (proto > 255)
797 			return -EINVAL;
798 
799 		daddr = &sin6->sin6_addr;
800 		if (np->sndflow) {
801 			fl6.flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK;
802 			if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
803 				flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
804 				if (IS_ERR(flowlabel))
805 					return -EINVAL;
806 			}
807 		}
808 
809 		/*
810 		 * Otherwise it will be difficult to maintain
811 		 * sk->sk_dst_cache.
812 		 */
813 		if (sk->sk_state == TCP_ESTABLISHED &&
814 		    ipv6_addr_equal(daddr, &sk->sk_v6_daddr))
815 			daddr = &sk->sk_v6_daddr;
816 
817 		if (addr_len >= sizeof(struct sockaddr_in6) &&
818 		    sin6->sin6_scope_id &&
819 		    __ipv6_addr_needs_scope_id(__ipv6_addr_type(daddr)))
820 			fl6.flowi6_oif = sin6->sin6_scope_id;
821 	} else {
822 		if (sk->sk_state != TCP_ESTABLISHED)
823 			return -EDESTADDRREQ;
824 
825 		proto = inet->inet_num;
826 		daddr = &sk->sk_v6_daddr;
827 		fl6.flowlabel = np->flow_label;
828 	}
829 
830 	if (fl6.flowi6_oif == 0)
831 		fl6.flowi6_oif = sk->sk_bound_dev_if;
832 
833 	if (msg->msg_controllen) {
834 		opt = &opt_space;
835 		memset(opt, 0, sizeof(struct ipv6_txoptions));
836 		opt->tot_len = sizeof(struct ipv6_txoptions);
837 		ipc6.opt = opt;
838 
839 		err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, &fl6, &ipc6);
840 		if (err < 0) {
841 			fl6_sock_release(flowlabel);
842 			return err;
843 		}
844 		if ((fl6.flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) {
845 			flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
846 			if (IS_ERR(flowlabel))
847 				return -EINVAL;
848 		}
849 		if (!(opt->opt_nflen|opt->opt_flen))
850 			opt = NULL;
851 	}
852 	if (!opt) {
853 		opt = txopt_get(np);
854 		opt_to_free = opt;
855 	}
856 	if (flowlabel)
857 		opt = fl6_merge_options(&opt_space, flowlabel, opt);
858 	opt = ipv6_fixup_options(&opt_space, opt);
859 
860 	fl6.flowi6_proto = proto;
861 	fl6.flowi6_mark = ipc6.sockc.mark;
862 
863 	if (!hdrincl) {
864 		rfv.msg = msg;
865 		rfv.hlen = 0;
866 		err = rawv6_probe_proto_opt(&rfv, &fl6);
867 		if (err)
868 			goto out;
869 	}
870 
871 	if (!ipv6_addr_any(daddr))
872 		fl6.daddr = *daddr;
873 	else
874 		fl6.daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */
875 	if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr))
876 		fl6.saddr = np->saddr;
877 
878 	final_p = fl6_update_dst(&fl6, opt, &final);
879 
880 	if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
881 		fl6.flowi6_oif = np->mcast_oif;
882 	else if (!fl6.flowi6_oif)
883 		fl6.flowi6_oif = np->ucast_oif;
884 	security_sk_classify_flow(sk, flowi6_to_flowi_common(&fl6));
885 
886 	if (hdrincl)
887 		fl6.flowi6_flags |= FLOWI_FLAG_KNOWN_NH;
888 
889 	if (ipc6.tclass < 0)
890 		ipc6.tclass = np->tclass;
891 
892 	fl6.flowlabel = ip6_make_flowinfo(ipc6.tclass, fl6.flowlabel);
893 
894 	dst = ip6_dst_lookup_flow(sock_net(sk), sk, &fl6, final_p);
895 	if (IS_ERR(dst)) {
896 		err = PTR_ERR(dst);
897 		goto out;
898 	}
899 	if (ipc6.hlimit < 0)
900 		ipc6.hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
901 
902 	if (ipc6.dontfrag < 0)
903 		ipc6.dontfrag = np->dontfrag;
904 
905 	if (msg->msg_flags&MSG_CONFIRM)
906 		goto do_confirm;
907 
908 back_from_confirm:
909 	if (hdrincl)
910 		err = rawv6_send_hdrinc(sk, msg, len, &fl6, &dst,
911 					msg->msg_flags, &ipc6.sockc);
912 	else {
913 		ipc6.opt = opt;
914 		lock_sock(sk);
915 		err = ip6_append_data(sk, raw6_getfrag, &rfv,
916 			len, 0, &ipc6, &fl6, (struct rt6_info *)dst,
917 			msg->msg_flags);
918 
919 		if (err)
920 			ip6_flush_pending_frames(sk);
921 		else if (!(msg->msg_flags & MSG_MORE))
922 			err = rawv6_push_pending_frames(sk, &fl6, rp);
923 		release_sock(sk);
924 	}
925 done:
926 	dst_release(dst);
927 out:
928 	fl6_sock_release(flowlabel);
929 	txopt_put(opt_to_free);
930 	return err < 0 ? err : len;
931 do_confirm:
932 	if (msg->msg_flags & MSG_PROBE)
933 		dst_confirm_neigh(dst, &fl6.daddr);
934 	if (!(msg->msg_flags & MSG_PROBE) || len)
935 		goto back_from_confirm;
936 	err = 0;
937 	goto done;
938 }
939 
940 static int rawv6_seticmpfilter(struct sock *sk, int level, int optname,
941 			       sockptr_t optval, int optlen)
942 {
943 	switch (optname) {
944 	case ICMPV6_FILTER:
945 		if (optlen > sizeof(struct icmp6_filter))
946 			optlen = sizeof(struct icmp6_filter);
947 		if (copy_from_sockptr(&raw6_sk(sk)->filter, optval, optlen))
948 			return -EFAULT;
949 		return 0;
950 	default:
951 		return -ENOPROTOOPT;
952 	}
953 
954 	return 0;
955 }
956 
957 static int rawv6_geticmpfilter(struct sock *sk, int level, int optname,
958 			       char __user *optval, int __user *optlen)
959 {
960 	int len;
961 
962 	switch (optname) {
963 	case ICMPV6_FILTER:
964 		if (get_user(len, optlen))
965 			return -EFAULT;
966 		if (len < 0)
967 			return -EINVAL;
968 		if (len > sizeof(struct icmp6_filter))
969 			len = sizeof(struct icmp6_filter);
970 		if (put_user(len, optlen))
971 			return -EFAULT;
972 		if (copy_to_user(optval, &raw6_sk(sk)->filter, len))
973 			return -EFAULT;
974 		return 0;
975 	default:
976 		return -ENOPROTOOPT;
977 	}
978 
979 	return 0;
980 }
981 
982 
983 static int do_rawv6_setsockopt(struct sock *sk, int level, int optname,
984 			       sockptr_t optval, unsigned int optlen)
985 {
986 	struct raw6_sock *rp = raw6_sk(sk);
987 	int val;
988 
989 	if (optlen < sizeof(val))
990 		return -EINVAL;
991 
992 	if (copy_from_sockptr(&val, optval, sizeof(val)))
993 		return -EFAULT;
994 
995 	switch (optname) {
996 	case IPV6_HDRINCL:
997 		if (sk->sk_type != SOCK_RAW)
998 			return -EINVAL;
999 		inet_sk(sk)->hdrincl = !!val;
1000 		return 0;
1001 	case IPV6_CHECKSUM:
1002 		if (inet_sk(sk)->inet_num == IPPROTO_ICMPV6 &&
1003 		    level == IPPROTO_IPV6) {
1004 			/*
1005 			 * RFC3542 tells that IPV6_CHECKSUM socket
1006 			 * option in the IPPROTO_IPV6 level is not
1007 			 * allowed on ICMPv6 sockets.
1008 			 * If you want to set it, use IPPROTO_RAW
1009 			 * level IPV6_CHECKSUM socket option
1010 			 * (Linux extension).
1011 			 */
1012 			return -EINVAL;
1013 		}
1014 
1015 		/* You may get strange result with a positive odd offset;
1016 		   RFC2292bis agrees with me. */
1017 		if (val > 0 && (val&1))
1018 			return -EINVAL;
1019 		if (val < 0) {
1020 			rp->checksum = 0;
1021 		} else {
1022 			rp->checksum = 1;
1023 			rp->offset = val;
1024 		}
1025 
1026 		return 0;
1027 
1028 	default:
1029 		return -ENOPROTOOPT;
1030 	}
1031 }
1032 
1033 static int rawv6_setsockopt(struct sock *sk, int level, int optname,
1034 			    sockptr_t optval, unsigned int optlen)
1035 {
1036 	switch (level) {
1037 	case SOL_RAW:
1038 		break;
1039 
1040 	case SOL_ICMPV6:
1041 		if (inet_sk(sk)->inet_num != IPPROTO_ICMPV6)
1042 			return -EOPNOTSUPP;
1043 		return rawv6_seticmpfilter(sk, level, optname, optval, optlen);
1044 	case SOL_IPV6:
1045 		if (optname == IPV6_CHECKSUM ||
1046 		    optname == IPV6_HDRINCL)
1047 			break;
1048 		fallthrough;
1049 	default:
1050 		return ipv6_setsockopt(sk, level, optname, optval, optlen);
1051 	}
1052 
1053 	return do_rawv6_setsockopt(sk, level, optname, optval, optlen);
1054 }
1055 
1056 static int do_rawv6_getsockopt(struct sock *sk, int level, int optname,
1057 			    char __user *optval, int __user *optlen)
1058 {
1059 	struct raw6_sock *rp = raw6_sk(sk);
1060 	int val, len;
1061 
1062 	if (get_user(len, optlen))
1063 		return -EFAULT;
1064 
1065 	switch (optname) {
1066 	case IPV6_HDRINCL:
1067 		val = inet_sk(sk)->hdrincl;
1068 		break;
1069 	case IPV6_CHECKSUM:
1070 		/*
1071 		 * We allow getsockopt() for IPPROTO_IPV6-level
1072 		 * IPV6_CHECKSUM socket option on ICMPv6 sockets
1073 		 * since RFC3542 is silent about it.
1074 		 */
1075 		if (rp->checksum == 0)
1076 			val = -1;
1077 		else
1078 			val = rp->offset;
1079 		break;
1080 
1081 	default:
1082 		return -ENOPROTOOPT;
1083 	}
1084 
1085 	len = min_t(unsigned int, sizeof(int), len);
1086 
1087 	if (put_user(len, optlen))
1088 		return -EFAULT;
1089 	if (copy_to_user(optval, &val, len))
1090 		return -EFAULT;
1091 	return 0;
1092 }
1093 
1094 static int rawv6_getsockopt(struct sock *sk, int level, int optname,
1095 			  char __user *optval, int __user *optlen)
1096 {
1097 	switch (level) {
1098 	case SOL_RAW:
1099 		break;
1100 
1101 	case SOL_ICMPV6:
1102 		if (inet_sk(sk)->inet_num != IPPROTO_ICMPV6)
1103 			return -EOPNOTSUPP;
1104 		return rawv6_geticmpfilter(sk, level, optname, optval, optlen);
1105 	case SOL_IPV6:
1106 		if (optname == IPV6_CHECKSUM ||
1107 		    optname == IPV6_HDRINCL)
1108 			break;
1109 		fallthrough;
1110 	default:
1111 		return ipv6_getsockopt(sk, level, optname, optval, optlen);
1112 	}
1113 
1114 	return do_rawv6_getsockopt(sk, level, optname, optval, optlen);
1115 }
1116 
1117 static int rawv6_ioctl(struct sock *sk, int cmd, unsigned long arg)
1118 {
1119 	switch (cmd) {
1120 	case SIOCOUTQ: {
1121 		int amount = sk_wmem_alloc_get(sk);
1122 
1123 		return put_user(amount, (int __user *)arg);
1124 	}
1125 	case SIOCINQ: {
1126 		struct sk_buff *skb;
1127 		int amount = 0;
1128 
1129 		spin_lock_bh(&sk->sk_receive_queue.lock);
1130 		skb = skb_peek(&sk->sk_receive_queue);
1131 		if (skb)
1132 			amount = skb->len;
1133 		spin_unlock_bh(&sk->sk_receive_queue.lock);
1134 		return put_user(amount, (int __user *)arg);
1135 	}
1136 
1137 	default:
1138 #ifdef CONFIG_IPV6_MROUTE
1139 		return ip6mr_ioctl(sk, cmd, (void __user *)arg);
1140 #else
1141 		return -ENOIOCTLCMD;
1142 #endif
1143 	}
1144 }
1145 
1146 #ifdef CONFIG_COMPAT
1147 static int compat_rawv6_ioctl(struct sock *sk, unsigned int cmd, unsigned long arg)
1148 {
1149 	switch (cmd) {
1150 	case SIOCOUTQ:
1151 	case SIOCINQ:
1152 		return -ENOIOCTLCMD;
1153 	default:
1154 #ifdef CONFIG_IPV6_MROUTE
1155 		return ip6mr_compat_ioctl(sk, cmd, compat_ptr(arg));
1156 #else
1157 		return -ENOIOCTLCMD;
1158 #endif
1159 	}
1160 }
1161 #endif
1162 
1163 static void rawv6_close(struct sock *sk, long timeout)
1164 {
1165 	if (inet_sk(sk)->inet_num == IPPROTO_RAW)
1166 		ip6_ra_control(sk, -1);
1167 	ip6mr_sk_done(sk);
1168 	sk_common_release(sk);
1169 }
1170 
1171 static void raw6_destroy(struct sock *sk)
1172 {
1173 	lock_sock(sk);
1174 	ip6_flush_pending_frames(sk);
1175 	release_sock(sk);
1176 
1177 	inet6_destroy_sock(sk);
1178 }
1179 
1180 static int rawv6_init_sk(struct sock *sk)
1181 {
1182 	struct raw6_sock *rp = raw6_sk(sk);
1183 
1184 	switch (inet_sk(sk)->inet_num) {
1185 	case IPPROTO_ICMPV6:
1186 		rp->checksum = 1;
1187 		rp->offset   = 2;
1188 		break;
1189 	case IPPROTO_MH:
1190 		rp->checksum = 1;
1191 		rp->offset   = 4;
1192 		break;
1193 	default:
1194 		break;
1195 	}
1196 	return 0;
1197 }
1198 
1199 struct proto rawv6_prot = {
1200 	.name		   = "RAWv6",
1201 	.owner		   = THIS_MODULE,
1202 	.close		   = rawv6_close,
1203 	.destroy	   = raw6_destroy,
1204 	.connect	   = ip6_datagram_connect_v6_only,
1205 	.disconnect	   = __udp_disconnect,
1206 	.ioctl		   = rawv6_ioctl,
1207 	.init		   = rawv6_init_sk,
1208 	.setsockopt	   = rawv6_setsockopt,
1209 	.getsockopt	   = rawv6_getsockopt,
1210 	.sendmsg	   = rawv6_sendmsg,
1211 	.recvmsg	   = rawv6_recvmsg,
1212 	.bind		   = rawv6_bind,
1213 	.backlog_rcv	   = rawv6_rcv_skb,
1214 	.hash		   = raw_hash_sk,
1215 	.unhash		   = raw_unhash_sk,
1216 	.obj_size	   = sizeof(struct raw6_sock),
1217 	.useroffset	   = offsetof(struct raw6_sock, filter),
1218 	.usersize	   = sizeof_field(struct raw6_sock, filter),
1219 	.h.raw_hash	   = &raw_v6_hashinfo,
1220 #ifdef CONFIG_COMPAT
1221 	.compat_ioctl	   = compat_rawv6_ioctl,
1222 #endif
1223 	.diag_destroy	   = raw_abort,
1224 };
1225 
1226 #ifdef CONFIG_PROC_FS
1227 static int raw6_seq_show(struct seq_file *seq, void *v)
1228 {
1229 	if (v == SEQ_START_TOKEN) {
1230 		seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
1231 	} else {
1232 		struct sock *sp = v;
1233 		__u16 srcp  = inet_sk(sp)->inet_num;
1234 		ip6_dgram_sock_seq_show(seq, v, srcp, 0,
1235 					raw_seq_private(seq)->bucket);
1236 	}
1237 	return 0;
1238 }
1239 
1240 static const struct seq_operations raw6_seq_ops = {
1241 	.start =	raw_seq_start,
1242 	.next =		raw_seq_next,
1243 	.stop =		raw_seq_stop,
1244 	.show =		raw6_seq_show,
1245 };
1246 
1247 static int __net_init raw6_init_net(struct net *net)
1248 {
1249 	if (!proc_create_net_data("raw6", 0444, net->proc_net, &raw6_seq_ops,
1250 			sizeof(struct raw_iter_state), &raw_v6_hashinfo))
1251 		return -ENOMEM;
1252 
1253 	return 0;
1254 }
1255 
1256 static void __net_exit raw6_exit_net(struct net *net)
1257 {
1258 	remove_proc_entry("raw6", net->proc_net);
1259 }
1260 
1261 static struct pernet_operations raw6_net_ops = {
1262 	.init = raw6_init_net,
1263 	.exit = raw6_exit_net,
1264 };
1265 
1266 int __init raw6_proc_init(void)
1267 {
1268 	return register_pernet_subsys(&raw6_net_ops);
1269 }
1270 
1271 void raw6_proc_exit(void)
1272 {
1273 	unregister_pernet_subsys(&raw6_net_ops);
1274 }
1275 #endif	/* CONFIG_PROC_FS */
1276 
1277 /* Same as inet6_dgram_ops, sans udp_poll.  */
1278 const struct proto_ops inet6_sockraw_ops = {
1279 	.family		   = PF_INET6,
1280 	.owner		   = THIS_MODULE,
1281 	.release	   = inet6_release,
1282 	.bind		   = inet6_bind,
1283 	.connect	   = inet_dgram_connect,	/* ok		*/
1284 	.socketpair	   = sock_no_socketpair,	/* a do nothing	*/
1285 	.accept		   = sock_no_accept,		/* a do nothing	*/
1286 	.getname	   = inet6_getname,
1287 	.poll		   = datagram_poll,		/* ok		*/
1288 	.ioctl		   = inet6_ioctl,		/* must change  */
1289 	.gettstamp	   = sock_gettstamp,
1290 	.listen		   = sock_no_listen,		/* ok		*/
1291 	.shutdown	   = inet_shutdown,		/* ok		*/
1292 	.setsockopt	   = sock_common_setsockopt,	/* ok		*/
1293 	.getsockopt	   = sock_common_getsockopt,	/* ok		*/
1294 	.sendmsg	   = inet_sendmsg,		/* ok		*/
1295 	.recvmsg	   = sock_common_recvmsg,	/* ok		*/
1296 	.mmap		   = sock_no_mmap,
1297 	.sendpage	   = sock_no_sendpage,
1298 #ifdef CONFIG_COMPAT
1299 	.compat_ioctl	   = inet6_compat_ioctl,
1300 #endif
1301 };
1302 
1303 static struct inet_protosw rawv6_protosw = {
1304 	.type		= SOCK_RAW,
1305 	.protocol	= IPPROTO_IP,	/* wild card */
1306 	.prot		= &rawv6_prot,
1307 	.ops		= &inet6_sockraw_ops,
1308 	.flags		= INET_PROTOSW_REUSE,
1309 };
1310 
1311 int __init rawv6_init(void)
1312 {
1313 	return inet6_register_protosw(&rawv6_protosw);
1314 }
1315 
1316 void rawv6_exit(void)
1317 {
1318 	inet6_unregister_protosw(&rawv6_protosw);
1319 }
1320