xref: /linux/net/ipv6/af_inet6.c (revision f7511d5f66f01fc451747b24e79f3ada7a3af9af)
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 #ifdef CONFIG_IPV6_MROUTE
65 #include <linux/mroute6.h>
66 #endif
67 
68 MODULE_AUTHOR("Cast of dozens");
69 MODULE_DESCRIPTION("IPv6 protocol stack for Linux");
70 MODULE_LICENSE("GPL");
71 
72 /* The inetsw6 table contains everything that inet6_create needs to
73  * build a new socket.
74  */
75 static struct list_head inetsw6[SOCK_MAX];
76 static DEFINE_SPINLOCK(inetsw6_lock);
77 
78 static __inline__ struct ipv6_pinfo *inet6_sk_generic(struct sock *sk)
79 {
80 	const int offset = sk->sk_prot->obj_size - sizeof(struct ipv6_pinfo);
81 
82 	return (struct ipv6_pinfo *)(((u8 *)sk) + offset);
83 }
84 
85 static int inet6_create(struct net *net, struct socket *sock, int protocol)
86 {
87 	struct inet_sock *inet;
88 	struct ipv6_pinfo *np;
89 	struct sock *sk;
90 	struct list_head *p;
91 	struct inet_protosw *answer;
92 	struct proto *answer_prot;
93 	unsigned char answer_flags;
94 	char answer_no_check;
95 	int try_loading_module = 0;
96 	int err;
97 
98 	if (sock->type != SOCK_RAW &&
99 	    sock->type != SOCK_DGRAM &&
100 	    !inet_ehash_secret)
101 		build_ehash_secret();
102 
103 	/* Look for the requested type/protocol pair. */
104 	answer = NULL;
105 lookup_protocol:
106 	err = -ESOCKTNOSUPPORT;
107 	rcu_read_lock();
108 	list_for_each_rcu(p, &inetsw6[sock->type]) {
109 		answer = list_entry(p, struct inet_protosw, list);
110 
111 		/* Check the non-wild match. */
112 		if (protocol == answer->protocol) {
113 			if (protocol != IPPROTO_IP)
114 				break;
115 		} else {
116 			/* Check for the two wild cases. */
117 			if (IPPROTO_IP == protocol) {
118 				protocol = answer->protocol;
119 				break;
120 			}
121 			if (IPPROTO_IP == answer->protocol)
122 				break;
123 		}
124 		err = -EPROTONOSUPPORT;
125 		answer = NULL;
126 	}
127 
128 	if (!answer) {
129 		if (try_loading_module < 2) {
130 			rcu_read_unlock();
131 			/*
132 			 * Be more specific, e.g. net-pf-10-proto-132-type-1
133 			 * (net-pf-PF_INET6-proto-IPPROTO_SCTP-type-SOCK_STREAM)
134 			 */
135 			if (++try_loading_module == 1)
136 				request_module("net-pf-%d-proto-%d-type-%d",
137 						PF_INET6, protocol, sock->type);
138 			/*
139 			 * Fall back to generic, e.g. net-pf-10-proto-132
140 			 * (net-pf-PF_INET6-proto-IPPROTO_SCTP)
141 			 */
142 			else
143 				request_module("net-pf-%d-proto-%d",
144 						PF_INET6, protocol);
145 			goto lookup_protocol;
146 		} else
147 			goto out_rcu_unlock;
148 	}
149 
150 	err = -EPERM;
151 	if (answer->capability > 0 && !capable(answer->capability))
152 		goto out_rcu_unlock;
153 
154 	sock->ops = answer->ops;
155 	answer_prot = answer->prot;
156 	answer_no_check = answer->no_check;
157 	answer_flags = answer->flags;
158 	rcu_read_unlock();
159 
160 	BUG_TRAP(answer_prot->slab != NULL);
161 
162 	err = -ENOBUFS;
163 	sk = sk_alloc(net, PF_INET6, GFP_KERNEL, answer_prot);
164 	if (sk == NULL)
165 		goto out;
166 
167 	sock_init_data(sock, sk);
168 
169 	err = 0;
170 	sk->sk_no_check = answer_no_check;
171 	if (INET_PROTOSW_REUSE & answer_flags)
172 		sk->sk_reuse = 1;
173 
174 	inet = inet_sk(sk);
175 	inet->is_icsk = (INET_PROTOSW_ICSK & answer_flags) != 0;
176 
177 	if (SOCK_RAW == sock->type) {
178 		inet->num = protocol;
179 		if (IPPROTO_RAW == protocol)
180 			inet->hdrincl = 1;
181 	}
182 
183 	sk->sk_destruct		= inet_sock_destruct;
184 	sk->sk_family		= PF_INET6;
185 	sk->sk_protocol		= protocol;
186 
187 	sk->sk_backlog_rcv	= answer->prot->backlog_rcv;
188 
189 	inet_sk(sk)->pinet6 = np = inet6_sk_generic(sk);
190 	np->hop_limit	= -1;
191 	np->mcast_hops	= -1;
192 	np->mc_loop	= 1;
193 	np->pmtudisc	= IPV6_PMTUDISC_WANT;
194 	np->ipv6only	= init_net.ipv6.sysctl.bindv6only;
195 
196 	/* Init the ipv4 part of the socket since we can have sockets
197 	 * using v6 API for ipv4.
198 	 */
199 	inet->uc_ttl	= -1;
200 
201 	inet->mc_loop	= 1;
202 	inet->mc_ttl	= 1;
203 	inet->mc_index	= 0;
204 	inet->mc_list	= NULL;
205 
206 	if (ipv4_config.no_pmtu_disc)
207 		inet->pmtudisc = IP_PMTUDISC_DONT;
208 	else
209 		inet->pmtudisc = IP_PMTUDISC_WANT;
210 	/*
211 	 * Increment only the relevant sk_prot->socks debug field, this changes
212 	 * the previous behaviour of incrementing both the equivalent to
213 	 * answer->prot->socks (inet6_sock_nr) and inet_sock_nr.
214 	 *
215 	 * This allows better debug granularity as we'll know exactly how many
216 	 * UDPv6, TCPv6, etc socks were allocated, not the sum of all IPv6
217 	 * transport protocol socks. -acme
218 	 */
219 	sk_refcnt_debug_inc(sk);
220 
221 	if (inet->num) {
222 		/* It assumes that any protocol which allows
223 		 * the user to assign a number at socket
224 		 * creation time automatically shares.
225 		 */
226 		inet->sport = htons(inet->num);
227 		sk->sk_prot->hash(sk);
228 	}
229 	if (sk->sk_prot->init) {
230 		err = sk->sk_prot->init(sk);
231 		if (err) {
232 			sk_common_release(sk);
233 			goto out;
234 		}
235 	}
236 out:
237 	return err;
238 out_rcu_unlock:
239 	rcu_read_unlock();
240 	goto out;
241 }
242 
243 
244 /* bind for INET6 API */
245 int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
246 {
247 	struct sockaddr_in6 *addr=(struct sockaddr_in6 *)uaddr;
248 	struct sock *sk = sock->sk;
249 	struct inet_sock *inet = inet_sk(sk);
250 	struct ipv6_pinfo *np = inet6_sk(sk);
251 	struct net *net = sock_net(sk);
252 	__be32 v4addr = 0;
253 	unsigned short snum;
254 	int addr_type = 0;
255 	int err = 0;
256 
257 	/* If the socket has its own bind function then use it. */
258 	if (sk->sk_prot->bind)
259 		return sk->sk_prot->bind(sk, uaddr, addr_len);
260 
261 	if (addr_len < SIN6_LEN_RFC2133)
262 		return -EINVAL;
263 	addr_type = ipv6_addr_type(&addr->sin6_addr);
264 	if ((addr_type & IPV6_ADDR_MULTICAST) && sock->type == SOCK_STREAM)
265 		return -EINVAL;
266 
267 	snum = ntohs(addr->sin6_port);
268 	if (snum && snum < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE))
269 		return -EACCES;
270 
271 	lock_sock(sk);
272 
273 	/* Check these errors (active socket, double bind). */
274 	if (sk->sk_state != TCP_CLOSE || inet->num) {
275 		err = -EINVAL;
276 		goto out;
277 	}
278 
279 	/* Check if the address belongs to the host. */
280 	if (addr_type == IPV6_ADDR_MAPPED) {
281 		v4addr = addr->sin6_addr.s6_addr32[3];
282 		if (inet_addr_type(net, v4addr) != RTN_LOCAL) {
283 			err = -EADDRNOTAVAIL;
284 			goto out;
285 		}
286 	} else {
287 		if (addr_type != IPV6_ADDR_ANY) {
288 			struct net_device *dev = NULL;
289 
290 			if (addr_type & IPV6_ADDR_LINKLOCAL) {
291 				if (addr_len >= sizeof(struct sockaddr_in6) &&
292 				    addr->sin6_scope_id) {
293 					/* Override any existing binding, if another one
294 					 * is supplied by user.
295 					 */
296 					sk->sk_bound_dev_if = addr->sin6_scope_id;
297 				}
298 
299 				/* Binding to link-local address requires an interface */
300 				if (!sk->sk_bound_dev_if) {
301 					err = -EINVAL;
302 					goto out;
303 				}
304 				dev = dev_get_by_index(net, sk->sk_bound_dev_if);
305 				if (!dev) {
306 					err = -ENODEV;
307 					goto out;
308 				}
309 			}
310 
311 			/* ipv4 addr of the socket is invalid.  Only the
312 			 * unspecified and mapped address have a v4 equivalent.
313 			 */
314 			v4addr = LOOPBACK4_IPV6;
315 			if (!(addr_type & IPV6_ADDR_MULTICAST))	{
316 				if (!ipv6_chk_addr(net, &addr->sin6_addr,
317 						   dev, 0)) {
318 					if (dev)
319 						dev_put(dev);
320 					err = -EADDRNOTAVAIL;
321 					goto out;
322 				}
323 			}
324 			if (dev)
325 				dev_put(dev);
326 		}
327 	}
328 
329 	inet->rcv_saddr = v4addr;
330 	inet->saddr = v4addr;
331 
332 	ipv6_addr_copy(&np->rcv_saddr, &addr->sin6_addr);
333 
334 	if (!(addr_type & IPV6_ADDR_MULTICAST))
335 		ipv6_addr_copy(&np->saddr, &addr->sin6_addr);
336 
337 	/* Make sure we are allowed to bind here. */
338 	if (sk->sk_prot->get_port(sk, snum)) {
339 		inet_reset_saddr(sk);
340 		err = -EADDRINUSE;
341 		goto out;
342 	}
343 
344 	if (addr_type != IPV6_ADDR_ANY)
345 		sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
346 	if (snum)
347 		sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
348 	inet->sport = htons(inet->num);
349 	inet->dport = 0;
350 	inet->daddr = 0;
351 out:
352 	release_sock(sk);
353 	return err;
354 }
355 
356 EXPORT_SYMBOL(inet6_bind);
357 
358 int inet6_release(struct socket *sock)
359 {
360 	struct sock *sk = sock->sk;
361 
362 	if (sk == NULL)
363 		return -EINVAL;
364 
365 	/* Free mc lists */
366 	ipv6_sock_mc_close(sk);
367 
368 	/* Free ac lists */
369 	ipv6_sock_ac_close(sk);
370 
371 	return inet_release(sock);
372 }
373 
374 EXPORT_SYMBOL(inet6_release);
375 
376 int inet6_destroy_sock(struct sock *sk)
377 {
378 	struct ipv6_pinfo *np = inet6_sk(sk);
379 	struct sk_buff *skb;
380 	struct ipv6_txoptions *opt;
381 
382 	/* Release rx options */
383 
384 	if ((skb = xchg(&np->pktoptions, NULL)) != NULL)
385 		kfree_skb(skb);
386 
387 	/* Free flowlabels */
388 	fl6_free_socklist(sk);
389 
390 	/* Free tx options */
391 
392 	if ((opt = xchg(&np->opt, NULL)) != NULL)
393 		sock_kfree_s(sk, opt, opt->tot_len);
394 
395 	return 0;
396 }
397 
398 EXPORT_SYMBOL_GPL(inet6_destroy_sock);
399 
400 /*
401  *	This does both peername and sockname.
402  */
403 
404 int inet6_getname(struct socket *sock, struct sockaddr *uaddr,
405 		 int *uaddr_len, int peer)
406 {
407 	struct sockaddr_in6 *sin=(struct sockaddr_in6 *)uaddr;
408 	struct sock *sk = sock->sk;
409 	struct inet_sock *inet = inet_sk(sk);
410 	struct ipv6_pinfo *np = inet6_sk(sk);
411 
412 	sin->sin6_family = AF_INET6;
413 	sin->sin6_flowinfo = 0;
414 	sin->sin6_scope_id = 0;
415 	if (peer) {
416 		if (!inet->dport)
417 			return -ENOTCONN;
418 		if (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
419 		    peer == 1)
420 			return -ENOTCONN;
421 		sin->sin6_port = inet->dport;
422 		ipv6_addr_copy(&sin->sin6_addr, &np->daddr);
423 		if (np->sndflow)
424 			sin->sin6_flowinfo = np->flow_label;
425 	} else {
426 		if (ipv6_addr_any(&np->rcv_saddr))
427 			ipv6_addr_copy(&sin->sin6_addr, &np->saddr);
428 		else
429 			ipv6_addr_copy(&sin->sin6_addr, &np->rcv_saddr);
430 
431 		sin->sin6_port = inet->sport;
432 	}
433 	if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
434 		sin->sin6_scope_id = sk->sk_bound_dev_if;
435 	*uaddr_len = sizeof(*sin);
436 	return(0);
437 }
438 
439 EXPORT_SYMBOL(inet6_getname);
440 
441 int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
442 {
443 	struct sock *sk = sock->sk;
444 	struct net *net = sock_net(sk);
445 
446 	switch(cmd)
447 	{
448 	case SIOCGSTAMP:
449 		return sock_get_timestamp(sk, (struct timeval __user *)arg);
450 
451 	case SIOCGSTAMPNS:
452 		return sock_get_timestampns(sk, (struct timespec __user *)arg);
453 
454 	case SIOCADDRT:
455 	case SIOCDELRT:
456 
457 		return(ipv6_route_ioctl(net, cmd, (void __user *)arg));
458 
459 	case SIOCSIFADDR:
460 		return addrconf_add_ifaddr(net, (void __user *) arg);
461 	case SIOCDIFADDR:
462 		return addrconf_del_ifaddr(net, (void __user *) arg);
463 	case SIOCSIFDSTADDR:
464 		return addrconf_set_dstaddr(net, (void __user *) arg);
465 	default:
466 		if (!sk->sk_prot->ioctl)
467 			return -ENOIOCTLCMD;
468 		return sk->sk_prot->ioctl(sk, cmd, arg);
469 	}
470 	/*NOTREACHED*/
471 	return(0);
472 }
473 
474 EXPORT_SYMBOL(inet6_ioctl);
475 
476 const struct proto_ops inet6_stream_ops = {
477 	.family		   = PF_INET6,
478 	.owner		   = THIS_MODULE,
479 	.release	   = inet6_release,
480 	.bind		   = inet6_bind,
481 	.connect	   = inet_stream_connect,	/* ok		*/
482 	.socketpair	   = sock_no_socketpair,	/* a do nothing	*/
483 	.accept		   = inet_accept,		/* ok		*/
484 	.getname	   = inet6_getname,
485 	.poll		   = tcp_poll,			/* ok		*/
486 	.ioctl		   = inet6_ioctl,		/* must change  */
487 	.listen		   = inet_listen,		/* ok		*/
488 	.shutdown	   = inet_shutdown,		/* ok		*/
489 	.setsockopt	   = sock_common_setsockopt,	/* ok		*/
490 	.getsockopt	   = sock_common_getsockopt,	/* ok		*/
491 	.sendmsg	   = tcp_sendmsg,		/* ok		*/
492 	.recvmsg	   = sock_common_recvmsg,	/* ok		*/
493 	.mmap		   = sock_no_mmap,
494 	.sendpage	   = tcp_sendpage,
495 	.splice_read	   = tcp_splice_read,
496 #ifdef CONFIG_COMPAT
497 	.compat_setsockopt = compat_sock_common_setsockopt,
498 	.compat_getsockopt = compat_sock_common_getsockopt,
499 #endif
500 };
501 
502 const struct proto_ops inet6_dgram_ops = {
503 	.family		   = PF_INET6,
504 	.owner		   = THIS_MODULE,
505 	.release	   = inet6_release,
506 	.bind		   = inet6_bind,
507 	.connect	   = inet_dgram_connect,	/* ok		*/
508 	.socketpair	   = sock_no_socketpair,	/* a do nothing	*/
509 	.accept		   = sock_no_accept,		/* a do nothing	*/
510 	.getname	   = inet6_getname,
511 	.poll		   = udp_poll,			/* ok		*/
512 	.ioctl		   = inet6_ioctl,		/* must change  */
513 	.listen		   = sock_no_listen,		/* ok		*/
514 	.shutdown	   = inet_shutdown,		/* ok		*/
515 	.setsockopt	   = sock_common_setsockopt,	/* ok		*/
516 	.getsockopt	   = sock_common_getsockopt,	/* ok		*/
517 	.sendmsg	   = inet_sendmsg,		/* ok		*/
518 	.recvmsg	   = sock_common_recvmsg,	/* ok		*/
519 	.mmap		   = sock_no_mmap,
520 	.sendpage	   = sock_no_sendpage,
521 #ifdef CONFIG_COMPAT
522 	.compat_setsockopt = compat_sock_common_setsockopt,
523 	.compat_getsockopt = compat_sock_common_getsockopt,
524 #endif
525 };
526 
527 static struct net_proto_family inet6_family_ops = {
528 	.family = PF_INET6,
529 	.create = inet6_create,
530 	.owner	= THIS_MODULE,
531 };
532 
533 int inet6_register_protosw(struct inet_protosw *p)
534 {
535 	struct list_head *lh;
536 	struct inet_protosw *answer;
537 	struct list_head *last_perm;
538 	int protocol = p->protocol;
539 	int ret;
540 
541 	spin_lock_bh(&inetsw6_lock);
542 
543 	ret = -EINVAL;
544 	if (p->type >= SOCK_MAX)
545 		goto out_illegal;
546 
547 	/* If we are trying to override a permanent protocol, bail. */
548 	answer = NULL;
549 	ret = -EPERM;
550 	last_perm = &inetsw6[p->type];
551 	list_for_each(lh, &inetsw6[p->type]) {
552 		answer = list_entry(lh, struct inet_protosw, list);
553 
554 		/* Check only the non-wild match. */
555 		if (INET_PROTOSW_PERMANENT & answer->flags) {
556 			if (protocol == answer->protocol)
557 				break;
558 			last_perm = lh;
559 		}
560 
561 		answer = NULL;
562 	}
563 	if (answer)
564 		goto out_permanent;
565 
566 	/* Add the new entry after the last permanent entry if any, so that
567 	 * the new entry does not override a permanent entry when matched with
568 	 * a wild-card protocol. But it is allowed to override any existing
569 	 * non-permanent entry.  This means that when we remove this entry, the
570 	 * system automatically returns to the old behavior.
571 	 */
572 	list_add_rcu(&p->list, last_perm);
573 	ret = 0;
574 out:
575 	spin_unlock_bh(&inetsw6_lock);
576 	return ret;
577 
578 out_permanent:
579 	printk(KERN_ERR "Attempt to override permanent protocol %d.\n",
580 	       protocol);
581 	goto out;
582 
583 out_illegal:
584 	printk(KERN_ERR
585 	       "Ignoring attempt to register invalid socket type %d.\n",
586 	       p->type);
587 	goto out;
588 }
589 
590 EXPORT_SYMBOL(inet6_register_protosw);
591 
592 void
593 inet6_unregister_protosw(struct inet_protosw *p)
594 {
595 	if (INET_PROTOSW_PERMANENT & p->flags) {
596 		printk(KERN_ERR
597 		       "Attempt to unregister permanent protocol %d.\n",
598 		       p->protocol);
599 	} else {
600 		spin_lock_bh(&inetsw6_lock);
601 		list_del_rcu(&p->list);
602 		spin_unlock_bh(&inetsw6_lock);
603 
604 		synchronize_net();
605 	}
606 }
607 
608 EXPORT_SYMBOL(inet6_unregister_protosw);
609 
610 int inet6_sk_rebuild_header(struct sock *sk)
611 {
612 	int err;
613 	struct dst_entry *dst;
614 	struct ipv6_pinfo *np = inet6_sk(sk);
615 
616 	dst = __sk_dst_check(sk, np->dst_cookie);
617 
618 	if (dst == NULL) {
619 		struct inet_sock *inet = inet_sk(sk);
620 		struct in6_addr *final_p = NULL, final;
621 		struct flowi fl;
622 
623 		memset(&fl, 0, sizeof(fl));
624 		fl.proto = sk->sk_protocol;
625 		ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
626 		ipv6_addr_copy(&fl.fl6_src, &np->saddr);
627 		fl.fl6_flowlabel = np->flow_label;
628 		fl.oif = sk->sk_bound_dev_if;
629 		fl.fl_ip_dport = inet->dport;
630 		fl.fl_ip_sport = inet->sport;
631 		security_sk_classify_flow(sk, &fl);
632 
633 		if (np->opt && np->opt->srcrt) {
634 			struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt;
635 			ipv6_addr_copy(&final, &fl.fl6_dst);
636 			ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
637 			final_p = &final;
638 		}
639 
640 		err = ip6_dst_lookup(sk, &dst, &fl);
641 		if (err) {
642 			sk->sk_route_caps = 0;
643 			return err;
644 		}
645 		if (final_p)
646 			ipv6_addr_copy(&fl.fl6_dst, final_p);
647 
648 		if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0) {
649 			sk->sk_err_soft = -err;
650 			return err;
651 		}
652 
653 		__ip6_dst_store(sk, dst, NULL, NULL);
654 	}
655 
656 	return 0;
657 }
658 
659 EXPORT_SYMBOL_GPL(inet6_sk_rebuild_header);
660 
661 int ipv6_opt_accepted(struct sock *sk, struct sk_buff *skb)
662 {
663 	struct ipv6_pinfo *np = inet6_sk(sk);
664 	struct inet6_skb_parm *opt = IP6CB(skb);
665 
666 	if (np->rxopt.all) {
667 		if ((opt->hop && (np->rxopt.bits.hopopts ||
668 				  np->rxopt.bits.ohopopts)) ||
669 		    ((IPV6_FLOWINFO_MASK &
670 		      *(__be32 *)skb_network_header(skb)) &&
671 		     np->rxopt.bits.rxflow) ||
672 		    (opt->srcrt && (np->rxopt.bits.srcrt ||
673 		     np->rxopt.bits.osrcrt)) ||
674 		    ((opt->dst1 || opt->dst0) &&
675 		     (np->rxopt.bits.dstopts || np->rxopt.bits.odstopts)))
676 			return 1;
677 	}
678 	return 0;
679 }
680 
681 EXPORT_SYMBOL_GPL(ipv6_opt_accepted);
682 
683 static struct inet6_protocol *ipv6_gso_pull_exthdrs(struct sk_buff *skb,
684 						    int proto)
685 {
686 	struct inet6_protocol *ops = NULL;
687 
688 	for (;;) {
689 		struct ipv6_opt_hdr *opth;
690 		int len;
691 
692 		if (proto != NEXTHDR_HOP) {
693 			ops = rcu_dereference(inet6_protos[proto]);
694 
695 			if (unlikely(!ops))
696 				break;
697 
698 			if (!(ops->flags & INET6_PROTO_GSO_EXTHDR))
699 				break;
700 		}
701 
702 		if (unlikely(!pskb_may_pull(skb, 8)))
703 			break;
704 
705 		opth = (void *)skb->data;
706 		len = ipv6_optlen(opth);
707 
708 		if (unlikely(!pskb_may_pull(skb, len)))
709 			break;
710 
711 		proto = opth->nexthdr;
712 		__skb_pull(skb, len);
713 	}
714 
715 	return ops;
716 }
717 
718 static int ipv6_gso_send_check(struct sk_buff *skb)
719 {
720 	struct ipv6hdr *ipv6h;
721 	struct inet6_protocol *ops;
722 	int err = -EINVAL;
723 
724 	if (unlikely(!pskb_may_pull(skb, sizeof(*ipv6h))))
725 		goto out;
726 
727 	ipv6h = ipv6_hdr(skb);
728 	__skb_pull(skb, sizeof(*ipv6h));
729 	err = -EPROTONOSUPPORT;
730 
731 	rcu_read_lock();
732 	ops = ipv6_gso_pull_exthdrs(skb, ipv6h->nexthdr);
733 	if (likely(ops && ops->gso_send_check)) {
734 		skb_reset_transport_header(skb);
735 		err = ops->gso_send_check(skb);
736 	}
737 	rcu_read_unlock();
738 
739 out:
740 	return err;
741 }
742 
743 static struct sk_buff *ipv6_gso_segment(struct sk_buff *skb, int features)
744 {
745 	struct sk_buff *segs = ERR_PTR(-EINVAL);
746 	struct ipv6hdr *ipv6h;
747 	struct inet6_protocol *ops;
748 
749 	if (!(features & NETIF_F_V6_CSUM))
750 		features &= ~NETIF_F_SG;
751 
752 	if (unlikely(skb_shinfo(skb)->gso_type &
753 		     ~(SKB_GSO_UDP |
754 		       SKB_GSO_DODGY |
755 		       SKB_GSO_TCP_ECN |
756 		       SKB_GSO_TCPV6 |
757 		       0)))
758 		goto out;
759 
760 	if (unlikely(!pskb_may_pull(skb, sizeof(*ipv6h))))
761 		goto out;
762 
763 	ipv6h = ipv6_hdr(skb);
764 	__skb_pull(skb, sizeof(*ipv6h));
765 	segs = ERR_PTR(-EPROTONOSUPPORT);
766 
767 	rcu_read_lock();
768 	ops = ipv6_gso_pull_exthdrs(skb, ipv6h->nexthdr);
769 	if (likely(ops && ops->gso_segment)) {
770 		skb_reset_transport_header(skb);
771 		segs = ops->gso_segment(skb, features);
772 	}
773 	rcu_read_unlock();
774 
775 	if (unlikely(IS_ERR(segs)))
776 		goto out;
777 
778 	for (skb = segs; skb; skb = skb->next) {
779 		ipv6h = ipv6_hdr(skb);
780 		ipv6h->payload_len = htons(skb->len - skb->mac_len -
781 					   sizeof(*ipv6h));
782 	}
783 
784 out:
785 	return segs;
786 }
787 
788 static struct packet_type ipv6_packet_type = {
789 	.type = __constant_htons(ETH_P_IPV6),
790 	.func = ipv6_rcv,
791 	.gso_send_check = ipv6_gso_send_check,
792 	.gso_segment = ipv6_gso_segment,
793 };
794 
795 static int __init ipv6_packet_init(void)
796 {
797 	dev_add_pack(&ipv6_packet_type);
798 	return 0;
799 }
800 
801 static void ipv6_packet_cleanup(void)
802 {
803 	dev_remove_pack(&ipv6_packet_type);
804 }
805 
806 static int __init init_ipv6_mibs(void)
807 {
808 	if (snmp_mib_init((void **)ipv6_statistics,
809 			  sizeof(struct ipstats_mib)) < 0)
810 		goto err_ip_mib;
811 	if (snmp_mib_init((void **)icmpv6_statistics,
812 			  sizeof(struct icmpv6_mib)) < 0)
813 		goto err_icmp_mib;
814 	if (snmp_mib_init((void **)icmpv6msg_statistics,
815 			  sizeof(struct icmpv6msg_mib)) < 0)
816 		goto err_icmpmsg_mib;
817 	if (snmp_mib_init((void **)udp_stats_in6, sizeof (struct udp_mib)) < 0)
818 		goto err_udp_mib;
819 	if (snmp_mib_init((void **)udplite_stats_in6,
820 			  sizeof (struct udp_mib)) < 0)
821 		goto err_udplite_mib;
822 	return 0;
823 
824 err_udplite_mib:
825 	snmp_mib_free((void **)udp_stats_in6);
826 err_udp_mib:
827 	snmp_mib_free((void **)icmpv6msg_statistics);
828 err_icmpmsg_mib:
829 	snmp_mib_free((void **)icmpv6_statistics);
830 err_icmp_mib:
831 	snmp_mib_free((void **)ipv6_statistics);
832 err_ip_mib:
833 	return -ENOMEM;
834 
835 }
836 
837 static void cleanup_ipv6_mibs(void)
838 {
839 	snmp_mib_free((void **)ipv6_statistics);
840 	snmp_mib_free((void **)icmpv6_statistics);
841 	snmp_mib_free((void **)icmpv6msg_statistics);
842 	snmp_mib_free((void **)udp_stats_in6);
843 	snmp_mib_free((void **)udplite_stats_in6);
844 }
845 
846 static int inet6_net_init(struct net *net)
847 {
848 	int err = 0;
849 
850 	net->ipv6.sysctl.bindv6only = 0;
851 	net->ipv6.sysctl.flush_delay = 0;
852 	net->ipv6.sysctl.ip6_rt_max_size = 4096;
853 	net->ipv6.sysctl.ip6_rt_gc_min_interval = HZ / 2;
854 	net->ipv6.sysctl.ip6_rt_gc_timeout = 60*HZ;
855 	net->ipv6.sysctl.ip6_rt_gc_interval = 30*HZ;
856 	net->ipv6.sysctl.ip6_rt_gc_elasticity = 9;
857 	net->ipv6.sysctl.ip6_rt_mtu_expires = 10*60*HZ;
858 	net->ipv6.sysctl.ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40;
859 	net->ipv6.sysctl.icmpv6_time = 1*HZ;
860 
861 #ifdef CONFIG_PROC_FS
862 	err = udp6_proc_init(net);
863 	if (err)
864 		goto out;
865 	err = tcp6_proc_init(net);
866 	if (err)
867 		goto proc_tcp6_fail;
868 	err = ac6_proc_init(net);
869 	if (err)
870 		goto proc_ac6_fail;
871 out:
872 #endif
873 	return err;
874 
875 #ifdef CONFIG_PROC_FS
876 proc_ac6_fail:
877 	tcp6_proc_exit(net);
878 proc_tcp6_fail:
879 	udp6_proc_exit(net);
880 	goto out;
881 #endif
882 }
883 
884 static void inet6_net_exit(struct net *net)
885 {
886 #ifdef CONFIG_PROC_FS
887 	udp6_proc_exit(net);
888 	tcp6_proc_exit(net);
889 	ac6_proc_exit(net);
890 #endif
891 }
892 
893 static struct pernet_operations inet6_net_ops = {
894 	.init = inet6_net_init,
895 	.exit = inet6_net_exit,
896 };
897 
898 static int __init inet6_init(void)
899 {
900 	struct sk_buff *dummy_skb;
901 	struct list_head *r;
902 	int err;
903 
904 	BUILD_BUG_ON(sizeof(struct inet6_skb_parm) > sizeof(dummy_skb->cb));
905 
906 	err = proto_register(&tcpv6_prot, 1);
907 	if (err)
908 		goto out;
909 
910 	err = proto_register(&udpv6_prot, 1);
911 	if (err)
912 		goto out_unregister_tcp_proto;
913 
914 	err = proto_register(&udplitev6_prot, 1);
915 	if (err)
916 		goto out_unregister_udp_proto;
917 
918 	err = proto_register(&rawv6_prot, 1);
919 	if (err)
920 		goto out_unregister_udplite_proto;
921 
922 
923 	/* Register the socket-side information for inet6_create.  */
924 	for(r = &inetsw6[0]; r < &inetsw6[SOCK_MAX]; ++r)
925 		INIT_LIST_HEAD(r);
926 
927 	/* We MUST register RAW sockets before we create the ICMP6,
928 	 * IGMP6, or NDISC control sockets.
929 	 */
930 	err = rawv6_init();
931 	if (err)
932 		goto out_unregister_raw_proto;
933 
934 	/* Register the family here so that the init calls below will
935 	 * be able to create sockets. (?? is this dangerous ??)
936 	 */
937 	err = sock_register(&inet6_family_ops);
938 	if (err)
939 		goto out_sock_register_fail;
940 
941 	/* Initialise ipv6 mibs */
942 	err = init_ipv6_mibs();
943 	if (err)
944 		goto out_unregister_sock;
945 
946 	/*
947 	 *	ipngwg API draft makes clear that the correct semantics
948 	 *	for TCP and UDP is to consider one TCP and UDP instance
949 	 *	in a host availiable by both INET and INET6 APIs and
950 	 *	able to communicate via both network protocols.
951 	 */
952 
953 	err = register_pernet_subsys(&inet6_net_ops);
954 	if (err)
955 		goto register_pernet_fail;
956 	err = icmpv6_init();
957 	if (err)
958 		goto icmp_fail;
959 #ifdef CONFIG_IPV6_MROUTE
960 	ip6_mr_init();
961 #endif
962 	err = ndisc_init();
963 	if (err)
964 		goto ndisc_fail;
965 	err = igmp6_init();
966 	if (err)
967 		goto igmp_fail;
968 	err = ipv6_netfilter_init();
969 	if (err)
970 		goto netfilter_fail;
971 	/* Create /proc/foo6 entries. */
972 #ifdef CONFIG_PROC_FS
973 	err = -ENOMEM;
974 	if (raw6_proc_init())
975 		goto proc_raw6_fail;
976 	if (udplite6_proc_init())
977 		goto proc_udplite6_fail;
978 	if (ipv6_misc_proc_init())
979 		goto proc_misc6_fail;
980 	if (if6_proc_init())
981 		goto proc_if6_fail;
982 #endif
983 	err = ip6_route_init();
984 	if (err)
985 		goto ip6_route_fail;
986 	err = ip6_flowlabel_init();
987 	if (err)
988 		goto ip6_flowlabel_fail;
989 	err = addrconf_init();
990 	if (err)
991 		goto addrconf_fail;
992 
993 	/* Init v6 extension headers. */
994 	err = ipv6_exthdrs_init();
995 	if (err)
996 		goto ipv6_exthdrs_fail;
997 
998 	err = ipv6_frag_init();
999 	if (err)
1000 		goto ipv6_frag_fail;
1001 
1002 	/* Init v6 transport protocols. */
1003 	err = udpv6_init();
1004 	if (err)
1005 		goto udpv6_fail;
1006 
1007 	err = udplitev6_init();
1008 	if (err)
1009 		goto udplitev6_fail;
1010 
1011 	err = tcpv6_init();
1012 	if (err)
1013 		goto tcpv6_fail;
1014 
1015 	err = ipv6_packet_init();
1016 	if (err)
1017 		goto ipv6_packet_fail;
1018 
1019 #ifdef CONFIG_SYSCTL
1020 	err = ipv6_sysctl_register();
1021 	if (err)
1022 		goto sysctl_fail;
1023 #endif
1024 out:
1025 	return err;
1026 
1027 #ifdef CONFIG_SYSCTL
1028 sysctl_fail:
1029 	ipv6_packet_cleanup();
1030 #endif
1031 ipv6_packet_fail:
1032 	tcpv6_exit();
1033 tcpv6_fail:
1034 	udplitev6_exit();
1035 udplitev6_fail:
1036 	udpv6_exit();
1037 udpv6_fail:
1038 	ipv6_frag_exit();
1039 ipv6_frag_fail:
1040 	ipv6_exthdrs_exit();
1041 ipv6_exthdrs_fail:
1042 	addrconf_cleanup();
1043 addrconf_fail:
1044 	ip6_flowlabel_cleanup();
1045 ip6_flowlabel_fail:
1046 	ip6_route_cleanup();
1047 ip6_route_fail:
1048 #ifdef CONFIG_PROC_FS
1049 	if6_proc_exit();
1050 proc_if6_fail:
1051 	ipv6_misc_proc_exit();
1052 proc_misc6_fail:
1053 	udplite6_proc_exit();
1054 proc_udplite6_fail:
1055 	raw6_proc_exit();
1056 proc_raw6_fail:
1057 #endif
1058 	ipv6_netfilter_fini();
1059 netfilter_fail:
1060 	igmp6_cleanup();
1061 igmp_fail:
1062 	ndisc_cleanup();
1063 ndisc_fail:
1064 	icmpv6_cleanup();
1065 icmp_fail:
1066 	unregister_pernet_subsys(&inet6_net_ops);
1067 register_pernet_fail:
1068 	cleanup_ipv6_mibs();
1069 out_unregister_sock:
1070 	sock_unregister(PF_INET6);
1071 	rtnl_unregister_all(PF_INET6);
1072 out_sock_register_fail:
1073 	rawv6_exit();
1074 out_unregister_raw_proto:
1075 	proto_unregister(&rawv6_prot);
1076 out_unregister_udplite_proto:
1077 	proto_unregister(&udplitev6_prot);
1078 out_unregister_udp_proto:
1079 	proto_unregister(&udpv6_prot);
1080 out_unregister_tcp_proto:
1081 	proto_unregister(&tcpv6_prot);
1082 	goto out;
1083 }
1084 module_init(inet6_init);
1085 
1086 static void __exit inet6_exit(void)
1087 {
1088 	/* First of all disallow new sockets creation. */
1089 	sock_unregister(PF_INET6);
1090 	/* Disallow any further netlink messages */
1091 	rtnl_unregister_all(PF_INET6);
1092 
1093 #ifdef CONFIG_SYSCTL
1094 	ipv6_sysctl_unregister();
1095 #endif
1096 	udpv6_exit();
1097 	udplitev6_exit();
1098 	tcpv6_exit();
1099 
1100 	/* Cleanup code parts. */
1101 	ipv6_packet_cleanup();
1102 	ipv6_frag_exit();
1103 	ipv6_exthdrs_exit();
1104 	addrconf_cleanup();
1105 	ip6_flowlabel_cleanup();
1106 	ip6_route_cleanup();
1107 #ifdef CONFIG_PROC_FS
1108 
1109 	/* Cleanup code parts. */
1110 	if6_proc_exit();
1111 	ipv6_misc_proc_exit();
1112 	udplite6_proc_exit();
1113 	raw6_proc_exit();
1114 #endif
1115 	ipv6_netfilter_fini();
1116 	igmp6_cleanup();
1117 	ndisc_cleanup();
1118 	icmpv6_cleanup();
1119 	rawv6_exit();
1120 
1121 	unregister_pernet_subsys(&inet6_net_ops);
1122 	cleanup_ipv6_mibs();
1123 	proto_unregister(&rawv6_prot);
1124 	proto_unregister(&udplitev6_prot);
1125 	proto_unregister(&udpv6_prot);
1126 	proto_unregister(&tcpv6_prot);
1127 }
1128 module_exit(inet6_exit);
1129 
1130 MODULE_ALIAS_NETPROTO(PF_INET6);
1131