xref: /linux/net/ipv6/af_inet6.c (revision 8b4a40809e5330c9da5d20107d693d92d73b31dc)
1 /*
2  *	PF_INET6 socket protocol family
3  *	Linux INET6 implementation
4  *
5  *	Authors:
6  *	Pedro Roque		<roque@di.fc.ul.pt>
7  *
8  *	Adapted from linux/net/ipv4/af_inet.c
9  *
10  *	$Id: af_inet6.c,v 1.66 2002/02/01 22:01:04 davem Exp $
11  *
12  * 	Fixes:
13  *	piggy, Karl Knutson	:	Socket protocol table
14  * 	Hideaki YOSHIFUJI	:	sin6_scope_id support
15  * 	Arnaldo Melo		: 	check proc_net_create return, cleanups
16  *
17  *	This program is free software; you can redistribute it and/or
18  *      modify it under the terms of the GNU General Public License
19  *      as published by the Free Software Foundation; either version
20  *      2 of the License, or (at your option) any later version.
21  */
22 
23 
24 #include <linux/module.h>
25 #include <linux/capability.h>
26 #include <linux/errno.h>
27 #include <linux/types.h>
28 #include <linux/socket.h>
29 #include <linux/in.h>
30 #include <linux/kernel.h>
31 #include <linux/timer.h>
32 #include <linux/string.h>
33 #include <linux/sockios.h>
34 #include <linux/net.h>
35 #include <linux/fcntl.h>
36 #include <linux/mm.h>
37 #include <linux/interrupt.h>
38 #include <linux/proc_fs.h>
39 #include <linux/stat.h>
40 #include <linux/init.h>
41 
42 #include <linux/inet.h>
43 #include <linux/netdevice.h>
44 #include <linux/icmpv6.h>
45 #include <linux/netfilter_ipv6.h>
46 
47 #include <net/ip.h>
48 #include <net/ipv6.h>
49 #include <net/udp.h>
50 #include <net/udplite.h>
51 #include <net/tcp.h>
52 #include <net/ipip.h>
53 #include <net/protocol.h>
54 #include <net/inet_common.h>
55 #include <net/transp_v6.h>
56 #include <net/ip6_route.h>
57 #include <net/addrconf.h>
58 #ifdef CONFIG_IPV6_TUNNEL
59 #include <net/ip6_tunnel.h>
60 #endif
61 
62 #include <asm/uaccess.h>
63 #include <asm/system.h>
64 
65 MODULE_AUTHOR("Cast of dozens");
66 MODULE_DESCRIPTION("IPv6 protocol stack for Linux");
67 MODULE_LICENSE("GPL");
68 
69 int sysctl_ipv6_bindv6only __read_mostly;
70 
71 /* The inetsw table contains everything that inet_create needs to
72  * build a new socket.
73  */
74 static struct list_head inetsw6[SOCK_MAX];
75 static DEFINE_SPINLOCK(inetsw6_lock);
76 
77 static __inline__ struct ipv6_pinfo *inet6_sk_generic(struct sock *sk)
78 {
79 	const int offset = sk->sk_prot->obj_size - sizeof(struct ipv6_pinfo);
80 
81 	return (struct ipv6_pinfo *)(((u8 *)sk) + offset);
82 }
83 
84 static int inet6_create(struct socket *sock, int protocol)
85 {
86 	struct inet_sock *inet;
87 	struct ipv6_pinfo *np;
88 	struct sock *sk;
89 	struct list_head *p;
90 	struct inet_protosw *answer;
91 	struct proto *answer_prot;
92 	unsigned char answer_flags;
93 	char answer_no_check;
94 	int try_loading_module = 0;
95 	int err;
96 
97 	if (sock->type != SOCK_RAW &&
98 	    sock->type != SOCK_DGRAM &&
99 	    !inet_ehash_secret)
100 		build_ehash_secret();
101 
102 	/* Look for the requested type/protocol pair. */
103 	answer = NULL;
104 lookup_protocol:
105 	err = -ESOCKTNOSUPPORT;
106 	rcu_read_lock();
107 	list_for_each_rcu(p, &inetsw6[sock->type]) {
108 		answer = list_entry(p, struct inet_protosw, list);
109 
110 		/* Check the non-wild match. */
111 		if (protocol == answer->protocol) {
112 			if (protocol != IPPROTO_IP)
113 				break;
114 		} else {
115 			/* Check for the two wild cases. */
116 			if (IPPROTO_IP == protocol) {
117 				protocol = answer->protocol;
118 				break;
119 			}
120 			if (IPPROTO_IP == answer->protocol)
121 				break;
122 		}
123 		err = -EPROTONOSUPPORT;
124 		answer = NULL;
125 	}
126 
127 	if (!answer) {
128 		if (try_loading_module < 2) {
129 			rcu_read_unlock();
130 			/*
131 			 * Be more specific, e.g. net-pf-10-proto-132-type-1
132 			 * (net-pf-PF_INET6-proto-IPPROTO_SCTP-type-SOCK_STREAM)
133 			 */
134 			if (++try_loading_module == 1)
135 				request_module("net-pf-%d-proto-%d-type-%d",
136 						PF_INET6, protocol, sock->type);
137 			/*
138 			 * Fall back to generic, e.g. net-pf-10-proto-132
139 			 * (net-pf-PF_INET6-proto-IPPROTO_SCTP)
140 			 */
141 			else
142 				request_module("net-pf-%d-proto-%d",
143 						PF_INET6, protocol);
144 			goto lookup_protocol;
145 		} else
146 			goto out_rcu_unlock;
147 	}
148 
149 	err = -EPERM;
150 	if (answer->capability > 0 && !capable(answer->capability))
151 		goto out_rcu_unlock;
152 
153 	sock->ops = answer->ops;
154 	answer_prot = answer->prot;
155 	answer_no_check = answer->no_check;
156 	answer_flags = answer->flags;
157 	rcu_read_unlock();
158 
159 	BUG_TRAP(answer_prot->slab != NULL);
160 
161 	err = -ENOBUFS;
162 	sk = sk_alloc(PF_INET6, GFP_KERNEL, answer_prot, 1);
163 	if (sk == NULL)
164 		goto out;
165 
166 	sock_init_data(sock, sk);
167 
168 	err = 0;
169 	sk->sk_no_check = answer_no_check;
170 	if (INET_PROTOSW_REUSE & answer_flags)
171 		sk->sk_reuse = 1;
172 
173 	inet = inet_sk(sk);
174 	inet->is_icsk = (INET_PROTOSW_ICSK & answer_flags) != 0;
175 
176 	if (SOCK_RAW == sock->type) {
177 		inet->num = protocol;
178 		if (IPPROTO_RAW == protocol)
179 			inet->hdrincl = 1;
180 	}
181 
182 	sk->sk_destruct		= inet_sock_destruct;
183 	sk->sk_family		= PF_INET6;
184 	sk->sk_protocol		= protocol;
185 
186 	sk->sk_backlog_rcv	= answer->prot->backlog_rcv;
187 
188 	inet_sk(sk)->pinet6 = np = inet6_sk_generic(sk);
189 	np->hop_limit	= -1;
190 	np->mcast_hops	= -1;
191 	np->mc_loop	= 1;
192 	np->pmtudisc	= IPV6_PMTUDISC_WANT;
193 	np->ipv6only	= sysctl_ipv6_bindv6only;
194 
195 	/* Init the ipv4 part of the socket since we can have sockets
196 	 * using v6 API for ipv4.
197 	 */
198 	inet->uc_ttl	= -1;
199 
200 	inet->mc_loop	= 1;
201 	inet->mc_ttl	= 1;
202 	inet->mc_index	= 0;
203 	inet->mc_list	= NULL;
204 
205 	if (ipv4_config.no_pmtu_disc)
206 		inet->pmtudisc = IP_PMTUDISC_DONT;
207 	else
208 		inet->pmtudisc = IP_PMTUDISC_WANT;
209 	/*
210 	 * Increment only the relevant sk_prot->socks debug field, this changes
211 	 * the previous behaviour of incrementing both the equivalent to
212 	 * answer->prot->socks (inet6_sock_nr) and inet_sock_nr.
213 	 *
214 	 * This allows better debug granularity as we'll know exactly how many
215 	 * UDPv6, TCPv6, etc socks were allocated, not the sum of all IPv6
216 	 * transport protocol socks. -acme
217 	 */
218 	sk_refcnt_debug_inc(sk);
219 
220 	if (inet->num) {
221 		/* It assumes that any protocol which allows
222 		 * the user to assign a number at socket
223 		 * creation time automatically shares.
224 		 */
225 		inet->sport = htons(inet->num);
226 		sk->sk_prot->hash(sk);
227 	}
228 	if (sk->sk_prot->init) {
229 		err = sk->sk_prot->init(sk);
230 		if (err) {
231 			sk_common_release(sk);
232 			goto out;
233 		}
234 	}
235 out:
236 	return err;
237 out_rcu_unlock:
238 	rcu_read_unlock();
239 	goto out;
240 }
241 
242 
243 /* bind for INET6 API */
244 int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
245 {
246 	struct sockaddr_in6 *addr=(struct sockaddr_in6 *)uaddr;
247 	struct sock *sk = sock->sk;
248 	struct inet_sock *inet = inet_sk(sk);
249 	struct ipv6_pinfo *np = inet6_sk(sk);
250 	__be32 v4addr = 0;
251 	unsigned short snum;
252 	int addr_type = 0;
253 	int err = 0;
254 
255 	/* If the socket has its own bind function then use it. */
256 	if (sk->sk_prot->bind)
257 		return sk->sk_prot->bind(sk, uaddr, addr_len);
258 
259 	if (addr_len < SIN6_LEN_RFC2133)
260 		return -EINVAL;
261 	addr_type = ipv6_addr_type(&addr->sin6_addr);
262 	if ((addr_type & IPV6_ADDR_MULTICAST) && sock->type == SOCK_STREAM)
263 		return -EINVAL;
264 
265 	snum = ntohs(addr->sin6_port);
266 	if (snum && snum < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE))
267 		return -EACCES;
268 
269 	lock_sock(sk);
270 
271 	/* Check these errors (active socket, double bind). */
272 	if (sk->sk_state != TCP_CLOSE || inet->num) {
273 		err = -EINVAL;
274 		goto out;
275 	}
276 
277 	/* Check if the address belongs to the host. */
278 	if (addr_type == IPV6_ADDR_MAPPED) {
279 		v4addr = addr->sin6_addr.s6_addr32[3];
280 		if (inet_addr_type(v4addr) != RTN_LOCAL) {
281 			err = -EADDRNOTAVAIL;
282 			goto out;
283 		}
284 	} else {
285 		if (addr_type != IPV6_ADDR_ANY) {
286 			struct net_device *dev = NULL;
287 
288 			if (addr_type & IPV6_ADDR_LINKLOCAL) {
289 				if (addr_len >= sizeof(struct sockaddr_in6) &&
290 				    addr->sin6_scope_id) {
291 					/* Override any existing binding, if another one
292 					 * is supplied by user.
293 					 */
294 					sk->sk_bound_dev_if = addr->sin6_scope_id;
295 				}
296 
297 				/* Binding to link-local address requires an interface */
298 				if (!sk->sk_bound_dev_if) {
299 					err = -EINVAL;
300 					goto out;
301 				}
302 				dev = dev_get_by_index(sk->sk_bound_dev_if);
303 				if (!dev) {
304 					err = -ENODEV;
305 					goto out;
306 				}
307 			}
308 
309 			/* ipv4 addr of the socket is invalid.  Only the
310 			 * unspecified and mapped address have a v4 equivalent.
311 			 */
312 			v4addr = LOOPBACK4_IPV6;
313 			if (!(addr_type & IPV6_ADDR_MULTICAST))	{
314 				if (!ipv6_chk_addr(&addr->sin6_addr, dev, 0)) {
315 					if (dev)
316 						dev_put(dev);
317 					err = -EADDRNOTAVAIL;
318 					goto out;
319 				}
320 			}
321 			if (dev)
322 				dev_put(dev);
323 		}
324 	}
325 
326 	inet->rcv_saddr = v4addr;
327 	inet->saddr = v4addr;
328 
329 	ipv6_addr_copy(&np->rcv_saddr, &addr->sin6_addr);
330 
331 	if (!(addr_type & IPV6_ADDR_MULTICAST))
332 		ipv6_addr_copy(&np->saddr, &addr->sin6_addr);
333 
334 	/* Make sure we are allowed to bind here. */
335 	if (sk->sk_prot->get_port(sk, snum)) {
336 		inet_reset_saddr(sk);
337 		err = -EADDRINUSE;
338 		goto out;
339 	}
340 
341 	if (addr_type != IPV6_ADDR_ANY)
342 		sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
343 	if (snum)
344 		sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
345 	inet->sport = htons(inet->num);
346 	inet->dport = 0;
347 	inet->daddr = 0;
348 out:
349 	release_sock(sk);
350 	return err;
351 }
352 
353 EXPORT_SYMBOL(inet6_bind);
354 
355 int inet6_release(struct socket *sock)
356 {
357 	struct sock *sk = sock->sk;
358 
359 	if (sk == NULL)
360 		return -EINVAL;
361 
362 	/* Free mc lists */
363 	ipv6_sock_mc_close(sk);
364 
365 	/* Free ac lists */
366 	ipv6_sock_ac_close(sk);
367 
368 	return inet_release(sock);
369 }
370 
371 EXPORT_SYMBOL(inet6_release);
372 
373 int inet6_destroy_sock(struct sock *sk)
374 {
375 	struct ipv6_pinfo *np = inet6_sk(sk);
376 	struct sk_buff *skb;
377 	struct ipv6_txoptions *opt;
378 
379 	/* Release rx options */
380 
381 	if ((skb = xchg(&np->pktoptions, NULL)) != NULL)
382 		kfree_skb(skb);
383 
384 	/* Free flowlabels */
385 	fl6_free_socklist(sk);
386 
387 	/* Free tx options */
388 
389 	if ((opt = xchg(&np->opt, NULL)) != NULL)
390 		sock_kfree_s(sk, opt, opt->tot_len);
391 
392 	return 0;
393 }
394 
395 EXPORT_SYMBOL_GPL(inet6_destroy_sock);
396 
397 /*
398  *	This does both peername and sockname.
399  */
400 
401 int inet6_getname(struct socket *sock, struct sockaddr *uaddr,
402 		 int *uaddr_len, int peer)
403 {
404 	struct sockaddr_in6 *sin=(struct sockaddr_in6 *)uaddr;
405 	struct sock *sk = sock->sk;
406 	struct inet_sock *inet = inet_sk(sk);
407 	struct ipv6_pinfo *np = inet6_sk(sk);
408 
409 	sin->sin6_family = AF_INET6;
410 	sin->sin6_flowinfo = 0;
411 	sin->sin6_scope_id = 0;
412 	if (peer) {
413 		if (!inet->dport)
414 			return -ENOTCONN;
415 		if (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
416 		    peer == 1)
417 			return -ENOTCONN;
418 		sin->sin6_port = inet->dport;
419 		ipv6_addr_copy(&sin->sin6_addr, &np->daddr);
420 		if (np->sndflow)
421 			sin->sin6_flowinfo = np->flow_label;
422 	} else {
423 		if (ipv6_addr_any(&np->rcv_saddr))
424 			ipv6_addr_copy(&sin->sin6_addr, &np->saddr);
425 		else
426 			ipv6_addr_copy(&sin->sin6_addr, &np->rcv_saddr);
427 
428 		sin->sin6_port = inet->sport;
429 	}
430 	if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
431 		sin->sin6_scope_id = sk->sk_bound_dev_if;
432 	*uaddr_len = sizeof(*sin);
433 	return(0);
434 }
435 
436 EXPORT_SYMBOL(inet6_getname);
437 
438 int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
439 {
440 	struct sock *sk = sock->sk;
441 
442 	switch(cmd)
443 	{
444 	case SIOCGSTAMP:
445 		return sock_get_timestamp(sk, (struct timeval __user *)arg);
446 
447 	case SIOCGSTAMPNS:
448 		return sock_get_timestampns(sk, (struct timespec __user *)arg);
449 
450 	case SIOCADDRT:
451 	case SIOCDELRT:
452 
453 		return(ipv6_route_ioctl(cmd,(void __user *)arg));
454 
455 	case SIOCSIFADDR:
456 		return addrconf_add_ifaddr((void __user *) arg);
457 	case SIOCDIFADDR:
458 		return addrconf_del_ifaddr((void __user *) arg);
459 	case SIOCSIFDSTADDR:
460 		return addrconf_set_dstaddr((void __user *) arg);
461 	default:
462 		if (!sk->sk_prot->ioctl)
463 			return -ENOIOCTLCMD;
464 		return sk->sk_prot->ioctl(sk, cmd, arg);
465 	}
466 	/*NOTREACHED*/
467 	return(0);
468 }
469 
470 EXPORT_SYMBOL(inet6_ioctl);
471 
472 const struct proto_ops inet6_stream_ops = {
473 	.family		   = PF_INET6,
474 	.owner		   = THIS_MODULE,
475 	.release	   = inet6_release,
476 	.bind		   = inet6_bind,
477 	.connect	   = inet_stream_connect,	/* ok		*/
478 	.socketpair	   = sock_no_socketpair,	/* a do nothing	*/
479 	.accept		   = inet_accept,		/* ok		*/
480 	.getname	   = inet6_getname,
481 	.poll		   = tcp_poll,			/* ok		*/
482 	.ioctl		   = inet6_ioctl,		/* must change  */
483 	.listen		   = inet_listen,		/* ok		*/
484 	.shutdown	   = inet_shutdown,		/* ok		*/
485 	.setsockopt	   = sock_common_setsockopt,	/* ok		*/
486 	.getsockopt	   = sock_common_getsockopt,	/* ok		*/
487 	.sendmsg	   = inet_sendmsg,		/* ok		*/
488 	.recvmsg	   = sock_common_recvmsg,	/* ok		*/
489 	.mmap		   = sock_no_mmap,
490 	.sendpage	   = tcp_sendpage,
491 #ifdef CONFIG_COMPAT
492 	.compat_setsockopt = compat_sock_common_setsockopt,
493 	.compat_getsockopt = compat_sock_common_getsockopt,
494 #endif
495 };
496 
497 const struct proto_ops inet6_dgram_ops = {
498 	.family		   = PF_INET6,
499 	.owner		   = THIS_MODULE,
500 	.release	   = inet6_release,
501 	.bind		   = inet6_bind,
502 	.connect	   = inet_dgram_connect,	/* ok		*/
503 	.socketpair	   = sock_no_socketpair,	/* a do nothing	*/
504 	.accept		   = sock_no_accept,		/* a do nothing	*/
505 	.getname	   = inet6_getname,
506 	.poll		   = udp_poll,			/* ok		*/
507 	.ioctl		   = inet6_ioctl,		/* must change  */
508 	.listen		   = sock_no_listen,		/* ok		*/
509 	.shutdown	   = inet_shutdown,		/* ok		*/
510 	.setsockopt	   = sock_common_setsockopt,	/* ok		*/
511 	.getsockopt	   = sock_common_getsockopt,	/* ok		*/
512 	.sendmsg	   = inet_sendmsg,		/* ok		*/
513 	.recvmsg	   = sock_common_recvmsg,	/* ok		*/
514 	.mmap		   = sock_no_mmap,
515 	.sendpage	   = sock_no_sendpage,
516 #ifdef CONFIG_COMPAT
517 	.compat_setsockopt = compat_sock_common_setsockopt,
518 	.compat_getsockopt = compat_sock_common_getsockopt,
519 #endif
520 };
521 
522 static struct net_proto_family inet6_family_ops = {
523 	.family = PF_INET6,
524 	.create = inet6_create,
525 	.owner	= THIS_MODULE,
526 };
527 
528 /* Same as inet6_dgram_ops, sans udp_poll.  */
529 static const struct proto_ops inet6_sockraw_ops = {
530 	.family		   = PF_INET6,
531 	.owner		   = THIS_MODULE,
532 	.release	   = inet6_release,
533 	.bind		   = inet6_bind,
534 	.connect	   = inet_dgram_connect,	/* ok		*/
535 	.socketpair	   = sock_no_socketpair,	/* a do nothing	*/
536 	.accept		   = sock_no_accept,		/* a do nothing	*/
537 	.getname	   = inet6_getname,
538 	.poll		   = datagram_poll,		/* ok		*/
539 	.ioctl		   = inet6_ioctl,		/* must change  */
540 	.listen		   = sock_no_listen,		/* ok		*/
541 	.shutdown	   = inet_shutdown,		/* ok		*/
542 	.setsockopt	   = sock_common_setsockopt,	/* ok		*/
543 	.getsockopt	   = sock_common_getsockopt,	/* ok		*/
544 	.sendmsg	   = inet_sendmsg,		/* ok		*/
545 	.recvmsg	   = sock_common_recvmsg,	/* ok		*/
546 	.mmap		   = sock_no_mmap,
547 	.sendpage	   = sock_no_sendpage,
548 #ifdef CONFIG_COMPAT
549 	.compat_setsockopt = compat_sock_common_setsockopt,
550 	.compat_getsockopt = compat_sock_common_getsockopt,
551 #endif
552 };
553 
554 static struct inet_protosw rawv6_protosw = {
555 	.type		= SOCK_RAW,
556 	.protocol	= IPPROTO_IP,	/* wild card */
557 	.prot		= &rawv6_prot,
558 	.ops		= &inet6_sockraw_ops,
559 	.capability	= CAP_NET_RAW,
560 	.no_check	= UDP_CSUM_DEFAULT,
561 	.flags		= INET_PROTOSW_REUSE,
562 };
563 
564 void
565 inet6_register_protosw(struct inet_protosw *p)
566 {
567 	struct list_head *lh;
568 	struct inet_protosw *answer;
569 	int protocol = p->protocol;
570 	struct list_head *last_perm;
571 
572 	spin_lock_bh(&inetsw6_lock);
573 
574 	if (p->type >= SOCK_MAX)
575 		goto out_illegal;
576 
577 	/* If we are trying to override a permanent protocol, bail. */
578 	answer = NULL;
579 	last_perm = &inetsw6[p->type];
580 	list_for_each(lh, &inetsw6[p->type]) {
581 		answer = list_entry(lh, struct inet_protosw, list);
582 
583 		/* Check only the non-wild match. */
584 		if (INET_PROTOSW_PERMANENT & answer->flags) {
585 			if (protocol == answer->protocol)
586 				break;
587 			last_perm = lh;
588 		}
589 
590 		answer = NULL;
591 	}
592 	if (answer)
593 		goto out_permanent;
594 
595 	/* Add the new entry after the last permanent entry if any, so that
596 	 * the new entry does not override a permanent entry when matched with
597 	 * a wild-card protocol. But it is allowed to override any existing
598 	 * non-permanent entry.  This means that when we remove this entry, the
599 	 * system automatically returns to the old behavior.
600 	 */
601 	list_add_rcu(&p->list, last_perm);
602 out:
603 	spin_unlock_bh(&inetsw6_lock);
604 	return;
605 
606 out_permanent:
607 	printk(KERN_ERR "Attempt to override permanent protocol %d.\n",
608 	       protocol);
609 	goto out;
610 
611 out_illegal:
612 	printk(KERN_ERR
613 	       "Ignoring attempt to register invalid socket type %d.\n",
614 	       p->type);
615 	goto out;
616 }
617 
618 EXPORT_SYMBOL(inet6_register_protosw);
619 
620 void
621 inet6_unregister_protosw(struct inet_protosw *p)
622 {
623 	if (INET_PROTOSW_PERMANENT & p->flags) {
624 		printk(KERN_ERR
625 		       "Attempt to unregister permanent protocol %d.\n",
626 		       p->protocol);
627 	} else {
628 		spin_lock_bh(&inetsw6_lock);
629 		list_del_rcu(&p->list);
630 		spin_unlock_bh(&inetsw6_lock);
631 
632 		synchronize_net();
633 	}
634 }
635 
636 EXPORT_SYMBOL(inet6_unregister_protosw);
637 
638 int inet6_sk_rebuild_header(struct sock *sk)
639 {
640 	int err;
641 	struct dst_entry *dst;
642 	struct ipv6_pinfo *np = inet6_sk(sk);
643 
644 	dst = __sk_dst_check(sk, np->dst_cookie);
645 
646 	if (dst == NULL) {
647 		struct inet_sock *inet = inet_sk(sk);
648 		struct in6_addr *final_p = NULL, final;
649 		struct flowi fl;
650 
651 		memset(&fl, 0, sizeof(fl));
652 		fl.proto = sk->sk_protocol;
653 		ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
654 		ipv6_addr_copy(&fl.fl6_src, &np->saddr);
655 		fl.fl6_flowlabel = np->flow_label;
656 		fl.oif = sk->sk_bound_dev_if;
657 		fl.fl_ip_dport = inet->dport;
658 		fl.fl_ip_sport = inet->sport;
659 		security_sk_classify_flow(sk, &fl);
660 
661 		if (np->opt && np->opt->srcrt) {
662 			struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt;
663 			ipv6_addr_copy(&final, &fl.fl6_dst);
664 			ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
665 			final_p = &final;
666 		}
667 
668 		err = ip6_dst_lookup(sk, &dst, &fl);
669 		if (err) {
670 			sk->sk_route_caps = 0;
671 			return err;
672 		}
673 		if (final_p)
674 			ipv6_addr_copy(&fl.fl6_dst, final_p);
675 
676 		if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0) {
677 			sk->sk_err_soft = -err;
678 			return err;
679 		}
680 
681 		__ip6_dst_store(sk, dst, NULL, NULL);
682 	}
683 
684 	return 0;
685 }
686 
687 EXPORT_SYMBOL_GPL(inet6_sk_rebuild_header);
688 
689 int ipv6_opt_accepted(struct sock *sk, struct sk_buff *skb)
690 {
691 	struct ipv6_pinfo *np = inet6_sk(sk);
692 	struct inet6_skb_parm *opt = IP6CB(skb);
693 
694 	if (np->rxopt.all) {
695 		if ((opt->hop && (np->rxopt.bits.hopopts ||
696 				  np->rxopt.bits.ohopopts)) ||
697 		    ((IPV6_FLOWINFO_MASK &
698 		      *(__be32 *)skb_network_header(skb)) &&
699 		     np->rxopt.bits.rxflow) ||
700 		    (opt->srcrt && (np->rxopt.bits.srcrt ||
701 		     np->rxopt.bits.osrcrt)) ||
702 		    ((opt->dst1 || opt->dst0) &&
703 		     (np->rxopt.bits.dstopts || np->rxopt.bits.odstopts)))
704 			return 1;
705 	}
706 	return 0;
707 }
708 
709 EXPORT_SYMBOL_GPL(ipv6_opt_accepted);
710 
711 static int __init init_ipv6_mibs(void)
712 {
713 	if (snmp_mib_init((void **)ipv6_statistics, sizeof (struct ipstats_mib),
714 			  __alignof__(struct ipstats_mib)) < 0)
715 		goto err_ip_mib;
716 	if (snmp_mib_init((void **)icmpv6_statistics, sizeof (struct icmpv6_mib),
717 			  __alignof__(struct icmpv6_mib)) < 0)
718 		goto err_icmp_mib;
719 	if (snmp_mib_init((void **)udp_stats_in6, sizeof (struct udp_mib),
720 			  __alignof__(struct udp_mib)) < 0)
721 		goto err_udp_mib;
722 	if (snmp_mib_init((void **)udplite_stats_in6, sizeof (struct udp_mib),
723 			  __alignof__(struct udp_mib)) < 0)
724 		goto err_udplite_mib;
725 	return 0;
726 
727 err_udplite_mib:
728 	snmp_mib_free((void **)udp_stats_in6);
729 err_udp_mib:
730 	snmp_mib_free((void **)icmpv6_statistics);
731 err_icmp_mib:
732 	snmp_mib_free((void **)ipv6_statistics);
733 err_ip_mib:
734 	return -ENOMEM;
735 
736 }
737 
738 static void cleanup_ipv6_mibs(void)
739 {
740 	snmp_mib_free((void **)ipv6_statistics);
741 	snmp_mib_free((void **)icmpv6_statistics);
742 	snmp_mib_free((void **)udp_stats_in6);
743 	snmp_mib_free((void **)udplite_stats_in6);
744 }
745 
746 static int __init inet6_init(void)
747 {
748 	struct sk_buff *dummy_skb;
749 	struct list_head *r;
750 	int err;
751 
752 	BUILD_BUG_ON(sizeof(struct inet6_skb_parm) > sizeof(dummy_skb->cb));
753 
754 #ifdef MODULE
755 #if 0 /* FIXME --RR */
756 	if (!mod_member_present(&__this_module, can_unload))
757 	  return -EINVAL;
758 
759 	__this_module.can_unload = &ipv6_unload;
760 #endif
761 #endif
762 
763 	err = proto_register(&tcpv6_prot, 1);
764 	if (err)
765 		goto out;
766 
767 	err = proto_register(&udpv6_prot, 1);
768 	if (err)
769 		goto out_unregister_tcp_proto;
770 
771 	err = proto_register(&udplitev6_prot, 1);
772 	if (err)
773 		goto out_unregister_udp_proto;
774 
775 	err = proto_register(&rawv6_prot, 1);
776 	if (err)
777 		goto out_unregister_udplite_proto;
778 
779 
780 	/* Register the socket-side information for inet6_create.  */
781 	for(r = &inetsw6[0]; r < &inetsw6[SOCK_MAX]; ++r)
782 		INIT_LIST_HEAD(r);
783 
784 	/* We MUST register RAW sockets before we create the ICMP6,
785 	 * IGMP6, or NDISC control sockets.
786 	 */
787 	inet6_register_protosw(&rawv6_protosw);
788 
789 	/* Register the family here so that the init calls below will
790 	 * be able to create sockets. (?? is this dangerous ??)
791 	 */
792 	err = sock_register(&inet6_family_ops);
793 	if (err)
794 		goto out_unregister_raw_proto;
795 
796 	/* Initialise ipv6 mibs */
797 	err = init_ipv6_mibs();
798 	if (err)
799 		goto out_unregister_sock;
800 
801 	/*
802 	 *	ipngwg API draft makes clear that the correct semantics
803 	 *	for TCP and UDP is to consider one TCP and UDP instance
804 	 *	in a host availiable by both INET and INET6 APIs and
805 	 *	able to communicate via both network protocols.
806 	 */
807 
808 #ifdef CONFIG_SYSCTL
809 	ipv6_sysctl_register();
810 #endif
811 	err = icmpv6_init(&inet6_family_ops);
812 	if (err)
813 		goto icmp_fail;
814 	err = ndisc_init(&inet6_family_ops);
815 	if (err)
816 		goto ndisc_fail;
817 	err = igmp6_init(&inet6_family_ops);
818 	if (err)
819 		goto igmp_fail;
820 	err = ipv6_netfilter_init();
821 	if (err)
822 		goto netfilter_fail;
823 	/* Create /proc/foo6 entries. */
824 #ifdef CONFIG_PROC_FS
825 	err = -ENOMEM;
826 	if (raw6_proc_init())
827 		goto proc_raw6_fail;
828 	if (tcp6_proc_init())
829 		goto proc_tcp6_fail;
830 	if (udp6_proc_init())
831 		goto proc_udp6_fail;
832 	if (udplite6_proc_init())
833 		goto proc_udplite6_fail;
834 	if (ipv6_misc_proc_init())
835 		goto proc_misc6_fail;
836 
837 	if (ac6_proc_init())
838 		goto proc_anycast6_fail;
839 	if (if6_proc_init())
840 		goto proc_if6_fail;
841 #endif
842 	ip6_route_init();
843 	ip6_flowlabel_init();
844 	err = addrconf_init();
845 	if (err)
846 		goto addrconf_fail;
847 
848 	/* Init v6 extension headers. */
849 	ipv6_rthdr_init();
850 	ipv6_frag_init();
851 	ipv6_nodata_init();
852 	ipv6_destopt_init();
853 
854 	/* Init v6 transport protocols. */
855 	udpv6_init();
856 	udplitev6_init();
857 	tcpv6_init();
858 
859 	ipv6_packet_init();
860 	err = 0;
861 out:
862 	return err;
863 
864 addrconf_fail:
865 	ip6_flowlabel_cleanup();
866 	ip6_route_cleanup();
867 #ifdef CONFIG_PROC_FS
868 	if6_proc_exit();
869 proc_if6_fail:
870 	ac6_proc_exit();
871 proc_anycast6_fail:
872 	ipv6_misc_proc_exit();
873 proc_misc6_fail:
874 	udplite6_proc_exit();
875 proc_udplite6_fail:
876 	udp6_proc_exit();
877 proc_udp6_fail:
878 	tcp6_proc_exit();
879 proc_tcp6_fail:
880 	raw6_proc_exit();
881 proc_raw6_fail:
882 #endif
883 	ipv6_netfilter_fini();
884 netfilter_fail:
885 	igmp6_cleanup();
886 igmp_fail:
887 	ndisc_cleanup();
888 ndisc_fail:
889 	icmpv6_cleanup();
890 icmp_fail:
891 #ifdef CONFIG_SYSCTL
892 	ipv6_sysctl_unregister();
893 #endif
894 	cleanup_ipv6_mibs();
895 out_unregister_sock:
896 	sock_unregister(PF_INET6);
897 out_unregister_raw_proto:
898 	proto_unregister(&rawv6_prot);
899 out_unregister_udplite_proto:
900 	proto_unregister(&udplitev6_prot);
901 out_unregister_udp_proto:
902 	proto_unregister(&udpv6_prot);
903 out_unregister_tcp_proto:
904 	proto_unregister(&tcpv6_prot);
905 	goto out;
906 }
907 module_init(inet6_init);
908 
909 static void __exit inet6_exit(void)
910 {
911 	/* First of all disallow new sockets creation. */
912 	sock_unregister(PF_INET6);
913 	/* Disallow any further netlink messages */
914 	rtnl_unregister_all(PF_INET6);
915 
916 	/* Cleanup code parts. */
917 	ipv6_packet_cleanup();
918 
919 	addrconf_cleanup();
920 	ip6_flowlabel_cleanup();
921 	ip6_route_cleanup();
922 #ifdef CONFIG_PROC_FS
923 
924 	/* Cleanup code parts. */
925 	if6_proc_exit();
926 	ac6_proc_exit();
927 	ipv6_misc_proc_exit();
928 	udplite6_proc_exit();
929 	udp6_proc_exit();
930 	tcp6_proc_exit();
931 	raw6_proc_exit();
932 #endif
933 	ipv6_netfilter_fini();
934 	igmp6_cleanup();
935 	ndisc_cleanup();
936 	icmpv6_cleanup();
937 #ifdef CONFIG_SYSCTL
938 	ipv6_sysctl_unregister();
939 #endif
940 	cleanup_ipv6_mibs();
941 	proto_unregister(&rawv6_prot);
942 	proto_unregister(&udplitev6_prot);
943 	proto_unregister(&udpv6_prot);
944 	proto_unregister(&tcpv6_prot);
945 }
946 module_exit(inet6_exit);
947 
948 MODULE_ALIAS_NETPROTO(PF_INET6);
949