xref: /linux/net/ipv6/af_inet6.c (revision 0c93ea4064a209cdc36de8a9a3003d43d08f46f7)
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  * 	Fixes:
11  *	piggy, Karl Knutson	:	Socket protocol table
12  * 	Hideaki YOSHIFUJI	:	sin6_scope_id support
13  * 	Arnaldo Melo		: 	check proc_net_create return, cleanups
14  *
15  *	This program is free software; you can redistribute it and/or
16  *      modify it under the terms of the GNU General Public License
17  *      as published by the Free Software Foundation; either version
18  *      2 of the License, or (at your option) any later version.
19  */
20 
21 
22 #include <linux/module.h>
23 #include <linux/capability.h>
24 #include <linux/errno.h>
25 #include <linux/types.h>
26 #include <linux/socket.h>
27 #include <linux/in.h>
28 #include <linux/kernel.h>
29 #include <linux/timer.h>
30 #include <linux/string.h>
31 #include <linux/sockios.h>
32 #include <linux/net.h>
33 #include <linux/fcntl.h>
34 #include <linux/mm.h>
35 #include <linux/interrupt.h>
36 #include <linux/proc_fs.h>
37 #include <linux/stat.h>
38 #include <linux/init.h>
39 
40 #include <linux/inet.h>
41 #include <linux/netdevice.h>
42 #include <linux/icmpv6.h>
43 #include <linux/netfilter_ipv6.h>
44 
45 #include <net/ip.h>
46 #include <net/ipv6.h>
47 #include <net/udp.h>
48 #include <net/udplite.h>
49 #include <net/tcp.h>
50 #include <net/ipip.h>
51 #include <net/protocol.h>
52 #include <net/inet_common.h>
53 #include <net/route.h>
54 #include <net/transp_v6.h>
55 #include <net/ip6_route.h>
56 #include <net/addrconf.h>
57 #ifdef CONFIG_IPV6_TUNNEL
58 #include <net/ip6_tunnel.h>
59 #endif
60 
61 #include <asm/uaccess.h>
62 #include <asm/system.h>
63 #include <linux/mroute6.h>
64 
65 MODULE_AUTHOR("Cast of dozens");
66 MODULE_DESCRIPTION("IPv6 protocol stack for Linux");
67 MODULE_LICENSE("GPL");
68 
69 /* The inetsw6 table contains everything that inet6_create needs to
70  * build a new socket.
71  */
72 static struct list_head inetsw6[SOCK_MAX];
73 static DEFINE_SPINLOCK(inetsw6_lock);
74 
75 static int disable_ipv6 = 0;
76 module_param_named(disable, disable_ipv6, int, 0);
77 MODULE_PARM_DESC(disable, "Disable IPv6 such that it is non-functional");
78 
79 static __inline__ struct ipv6_pinfo *inet6_sk_generic(struct sock *sk)
80 {
81 	const int offset = sk->sk_prot->obj_size - sizeof(struct ipv6_pinfo);
82 
83 	return (struct ipv6_pinfo *)(((u8 *)sk) + offset);
84 }
85 
86 static int inet6_create(struct net *net, struct socket *sock, int protocol)
87 {
88 	struct inet_sock *inet;
89 	struct ipv6_pinfo *np;
90 	struct sock *sk;
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 lookup_protocol:
105 	err = -ESOCKTNOSUPPORT;
106 	rcu_read_lock();
107 	list_for_each_entry_rcu(answer, &inetsw6[sock->type], list) {
108 
109 		err = 0;
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 	}
125 
126 	if (err) {
127 		if (try_loading_module < 2) {
128 			rcu_read_unlock();
129 			/*
130 			 * Be more specific, e.g. net-pf-10-proto-132-type-1
131 			 * (net-pf-PF_INET6-proto-IPPROTO_SCTP-type-SOCK_STREAM)
132 			 */
133 			if (++try_loading_module == 1)
134 				request_module("net-pf-%d-proto-%d-type-%d",
135 						PF_INET6, protocol, sock->type);
136 			/*
137 			 * Fall back to generic, e.g. net-pf-10-proto-132
138 			 * (net-pf-PF_INET6-proto-IPPROTO_SCTP)
139 			 */
140 			else
141 				request_module("net-pf-%d-proto-%d",
142 						PF_INET6, protocol);
143 			goto lookup_protocol;
144 		} else
145 			goto out_rcu_unlock;
146 	}
147 
148 	err = -EPERM;
149 	if (answer->capability > 0 && !capable(answer->capability))
150 		goto out_rcu_unlock;
151 
152 	sock->ops = answer->ops;
153 	answer_prot = answer->prot;
154 	answer_no_check = answer->no_check;
155 	answer_flags = answer->flags;
156 	rcu_read_unlock();
157 
158 	WARN_ON(answer_prot->slab == NULL);
159 
160 	err = -ENOBUFS;
161 	sk = sk_alloc(net, PF_INET6, GFP_KERNEL, answer_prot);
162 	if (sk == NULL)
163 		goto out;
164 
165 	sock_init_data(sock, sk);
166 
167 	err = 0;
168 	sk->sk_no_check = answer_no_check;
169 	if (INET_PROTOSW_REUSE & answer_flags)
170 		sk->sk_reuse = 1;
171 
172 	inet = inet_sk(sk);
173 	inet->is_icsk = (INET_PROTOSW_ICSK & answer_flags) != 0;
174 
175 	if (SOCK_RAW == sock->type) {
176 		inet->num = protocol;
177 		if (IPPROTO_RAW == protocol)
178 			inet->hdrincl = 1;
179 	}
180 
181 	sk->sk_destruct		= inet_sock_destruct;
182 	sk->sk_family		= PF_INET6;
183 	sk->sk_protocol		= protocol;
184 
185 	sk->sk_backlog_rcv	= answer->prot->backlog_rcv;
186 
187 	inet_sk(sk)->pinet6 = np = inet6_sk_generic(sk);
188 	np->hop_limit	= -1;
189 	np->mcast_hops	= -1;
190 	np->mc_loop	= 1;
191 	np->pmtudisc	= IPV6_PMTUDISC_WANT;
192 	np->ipv6only	= net->ipv6.sysctl.bindv6only;
193 
194 	/* Init the ipv4 part of the socket since we can have sockets
195 	 * using v6 API for ipv4.
196 	 */
197 	inet->uc_ttl	= -1;
198 
199 	inet->mc_loop	= 1;
200 	inet->mc_ttl	= 1;
201 	inet->mc_index	= 0;
202 	inet->mc_list	= NULL;
203 
204 	if (ipv4_config.no_pmtu_disc)
205 		inet->pmtudisc = IP_PMTUDISC_DONT;
206 	else
207 		inet->pmtudisc = IP_PMTUDISC_WANT;
208 	/*
209 	 * Increment only the relevant sk_prot->socks debug field, this changes
210 	 * the previous behaviour of incrementing both the equivalent to
211 	 * answer->prot->socks (inet6_sock_nr) and inet_sock_nr.
212 	 *
213 	 * This allows better debug granularity as we'll know exactly how many
214 	 * UDPv6, TCPv6, etc socks were allocated, not the sum of all IPv6
215 	 * transport protocol socks. -acme
216 	 */
217 	sk_refcnt_debug_inc(sk);
218 
219 	if (inet->num) {
220 		/* It assumes that any protocol which allows
221 		 * the user to assign a number at socket
222 		 * creation time automatically shares.
223 		 */
224 		inet->sport = htons(inet->num);
225 		sk->sk_prot->hash(sk);
226 	}
227 	if (sk->sk_prot->init) {
228 		err = sk->sk_prot->init(sk);
229 		if (err) {
230 			sk_common_release(sk);
231 			goto out;
232 		}
233 	}
234 out:
235 	return err;
236 out_rcu_unlock:
237 	rcu_read_unlock();
238 	goto out;
239 }
240 
241 
242 /* bind for INET6 API */
243 int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
244 {
245 	struct sockaddr_in6 *addr=(struct sockaddr_in6 *)uaddr;
246 	struct sock *sk = sock->sk;
247 	struct inet_sock *inet = inet_sk(sk);
248 	struct ipv6_pinfo *np = inet6_sk(sk);
249 	struct net *net = sock_net(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(net, 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(net, 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(net, &addr->sin6_addr,
315 						   dev, 0)) {
316 					if (dev)
317 						dev_put(dev);
318 					err = -EADDRNOTAVAIL;
319 					goto out;
320 				}
321 			}
322 			if (dev)
323 				dev_put(dev);
324 		}
325 	}
326 
327 	inet->rcv_saddr = v4addr;
328 	inet->saddr = v4addr;
329 
330 	ipv6_addr_copy(&np->rcv_saddr, &addr->sin6_addr);
331 
332 	if (!(addr_type & IPV6_ADDR_MULTICAST))
333 		ipv6_addr_copy(&np->saddr, &addr->sin6_addr);
334 
335 	/* Make sure we are allowed to bind here. */
336 	if (sk->sk_prot->get_port(sk, snum)) {
337 		inet_reset_saddr(sk);
338 		err = -EADDRINUSE;
339 		goto out;
340 	}
341 
342 	if (addr_type != IPV6_ADDR_ANY)
343 		sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
344 	if (snum)
345 		sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
346 	inet->sport = htons(inet->num);
347 	inet->dport = 0;
348 	inet->daddr = 0;
349 out:
350 	release_sock(sk);
351 	return err;
352 }
353 
354 EXPORT_SYMBOL(inet6_bind);
355 
356 int inet6_release(struct socket *sock)
357 {
358 	struct sock *sk = sock->sk;
359 
360 	if (sk == NULL)
361 		return -EINVAL;
362 
363 	/* Free mc lists */
364 	ipv6_sock_mc_close(sk);
365 
366 	/* Free ac lists */
367 	ipv6_sock_ac_close(sk);
368 
369 	return inet_release(sock);
370 }
371 
372 EXPORT_SYMBOL(inet6_release);
373 
374 void inet6_destroy_sock(struct sock *sk)
375 {
376 	struct ipv6_pinfo *np = inet6_sk(sk);
377 	struct sk_buff *skb;
378 	struct ipv6_txoptions *opt;
379 
380 	/* Release rx options */
381 
382 	if ((skb = xchg(&np->pktoptions, NULL)) != NULL)
383 		kfree_skb(skb);
384 
385 	/* Free flowlabels */
386 	fl6_free_socklist(sk);
387 
388 	/* Free tx options */
389 
390 	if ((opt = xchg(&np->opt, NULL)) != NULL)
391 		sock_kfree_s(sk, opt, opt->tot_len);
392 }
393 
394 EXPORT_SYMBOL_GPL(inet6_destroy_sock);
395 
396 /*
397  *	This does both peername and sockname.
398  */
399 
400 int inet6_getname(struct socket *sock, struct sockaddr *uaddr,
401 		 int *uaddr_len, int peer)
402 {
403 	struct sockaddr_in6 *sin=(struct sockaddr_in6 *)uaddr;
404 	struct sock *sk = sock->sk;
405 	struct inet_sock *inet = inet_sk(sk);
406 	struct ipv6_pinfo *np = inet6_sk(sk);
407 
408 	sin->sin6_family = AF_INET6;
409 	sin->sin6_flowinfo = 0;
410 	sin->sin6_scope_id = 0;
411 	if (peer) {
412 		if (!inet->dport)
413 			return -ENOTCONN;
414 		if (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
415 		    peer == 1)
416 			return -ENOTCONN;
417 		sin->sin6_port = inet->dport;
418 		ipv6_addr_copy(&sin->sin6_addr, &np->daddr);
419 		if (np->sndflow)
420 			sin->sin6_flowinfo = np->flow_label;
421 	} else {
422 		if (ipv6_addr_any(&np->rcv_saddr))
423 			ipv6_addr_copy(&sin->sin6_addr, &np->saddr);
424 		else
425 			ipv6_addr_copy(&sin->sin6_addr, &np->rcv_saddr);
426 
427 		sin->sin6_port = inet->sport;
428 	}
429 	if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
430 		sin->sin6_scope_id = sk->sk_bound_dev_if;
431 	*uaddr_len = sizeof(*sin);
432 	return(0);
433 }
434 
435 EXPORT_SYMBOL(inet6_getname);
436 
437 int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
438 {
439 	struct sock *sk = sock->sk;
440 	struct net *net = sock_net(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(net, cmd, (void __user *)arg));
454 
455 	case SIOCSIFADDR:
456 		return addrconf_add_ifaddr(net, (void __user *) arg);
457 	case SIOCDIFADDR:
458 		return addrconf_del_ifaddr(net, (void __user *) arg);
459 	case SIOCSIFDSTADDR:
460 		return addrconf_set_dstaddr(net, (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	   = tcp_sendmsg,		/* ok		*/
488 	.recvmsg	   = sock_common_recvmsg,	/* ok		*/
489 	.mmap		   = sock_no_mmap,
490 	.sendpage	   = tcp_sendpage,
491 	.splice_read	   = tcp_splice_read,
492 #ifdef CONFIG_COMPAT
493 	.compat_setsockopt = compat_sock_common_setsockopt,
494 	.compat_getsockopt = compat_sock_common_getsockopt,
495 #endif
496 };
497 
498 const struct proto_ops inet6_dgram_ops = {
499 	.family		   = PF_INET6,
500 	.owner		   = THIS_MODULE,
501 	.release	   = inet6_release,
502 	.bind		   = inet6_bind,
503 	.connect	   = inet_dgram_connect,	/* ok		*/
504 	.socketpair	   = sock_no_socketpair,	/* a do nothing	*/
505 	.accept		   = sock_no_accept,		/* a do nothing	*/
506 	.getname	   = inet6_getname,
507 	.poll		   = udp_poll,			/* ok		*/
508 	.ioctl		   = inet6_ioctl,		/* must change  */
509 	.listen		   = sock_no_listen,		/* ok		*/
510 	.shutdown	   = inet_shutdown,		/* ok		*/
511 	.setsockopt	   = sock_common_setsockopt,	/* ok		*/
512 	.getsockopt	   = sock_common_getsockopt,	/* ok		*/
513 	.sendmsg	   = inet_sendmsg,		/* ok		*/
514 	.recvmsg	   = sock_common_recvmsg,	/* ok		*/
515 	.mmap		   = sock_no_mmap,
516 	.sendpage	   = sock_no_sendpage,
517 #ifdef CONFIG_COMPAT
518 	.compat_setsockopt = compat_sock_common_setsockopt,
519 	.compat_getsockopt = compat_sock_common_getsockopt,
520 #endif
521 };
522 
523 static struct net_proto_family inet6_family_ops = {
524 	.family = PF_INET6,
525 	.create = inet6_create,
526 	.owner	= THIS_MODULE,
527 };
528 
529 int inet6_register_protosw(struct inet_protosw *p)
530 {
531 	struct list_head *lh;
532 	struct inet_protosw *answer;
533 	struct list_head *last_perm;
534 	int protocol = p->protocol;
535 	int ret;
536 
537 	spin_lock_bh(&inetsw6_lock);
538 
539 	ret = -EINVAL;
540 	if (p->type >= SOCK_MAX)
541 		goto out_illegal;
542 
543 	/* If we are trying to override a permanent protocol, bail. */
544 	answer = NULL;
545 	ret = -EPERM;
546 	last_perm = &inetsw6[p->type];
547 	list_for_each(lh, &inetsw6[p->type]) {
548 		answer = list_entry(lh, struct inet_protosw, list);
549 
550 		/* Check only the non-wild match. */
551 		if (INET_PROTOSW_PERMANENT & answer->flags) {
552 			if (protocol == answer->protocol)
553 				break;
554 			last_perm = lh;
555 		}
556 
557 		answer = NULL;
558 	}
559 	if (answer)
560 		goto out_permanent;
561 
562 	/* Add the new entry after the last permanent entry if any, so that
563 	 * the new entry does not override a permanent entry when matched with
564 	 * a wild-card protocol. But it is allowed to override any existing
565 	 * non-permanent entry.  This means that when we remove this entry, the
566 	 * system automatically returns to the old behavior.
567 	 */
568 	list_add_rcu(&p->list, last_perm);
569 	ret = 0;
570 out:
571 	spin_unlock_bh(&inetsw6_lock);
572 	return ret;
573 
574 out_permanent:
575 	printk(KERN_ERR "Attempt to override permanent protocol %d.\n",
576 	       protocol);
577 	goto out;
578 
579 out_illegal:
580 	printk(KERN_ERR
581 	       "Ignoring attempt to register invalid socket type %d.\n",
582 	       p->type);
583 	goto out;
584 }
585 
586 EXPORT_SYMBOL(inet6_register_protosw);
587 
588 void
589 inet6_unregister_protosw(struct inet_protosw *p)
590 {
591 	if (INET_PROTOSW_PERMANENT & p->flags) {
592 		printk(KERN_ERR
593 		       "Attempt to unregister permanent protocol %d.\n",
594 		       p->protocol);
595 	} else {
596 		spin_lock_bh(&inetsw6_lock);
597 		list_del_rcu(&p->list);
598 		spin_unlock_bh(&inetsw6_lock);
599 
600 		synchronize_net();
601 	}
602 }
603 
604 EXPORT_SYMBOL(inet6_unregister_protosw);
605 
606 int inet6_sk_rebuild_header(struct sock *sk)
607 {
608 	int err;
609 	struct dst_entry *dst;
610 	struct ipv6_pinfo *np = inet6_sk(sk);
611 
612 	dst = __sk_dst_check(sk, np->dst_cookie);
613 
614 	if (dst == NULL) {
615 		struct inet_sock *inet = inet_sk(sk);
616 		struct in6_addr *final_p = NULL, final;
617 		struct flowi fl;
618 
619 		memset(&fl, 0, sizeof(fl));
620 		fl.proto = sk->sk_protocol;
621 		ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
622 		ipv6_addr_copy(&fl.fl6_src, &np->saddr);
623 		fl.fl6_flowlabel = np->flow_label;
624 		fl.oif = sk->sk_bound_dev_if;
625 		fl.fl_ip_dport = inet->dport;
626 		fl.fl_ip_sport = inet->sport;
627 		security_sk_classify_flow(sk, &fl);
628 
629 		if (np->opt && np->opt->srcrt) {
630 			struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt;
631 			ipv6_addr_copy(&final, &fl.fl6_dst);
632 			ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
633 			final_p = &final;
634 		}
635 
636 		err = ip6_dst_lookup(sk, &dst, &fl);
637 		if (err) {
638 			sk->sk_route_caps = 0;
639 			return err;
640 		}
641 		if (final_p)
642 			ipv6_addr_copy(&fl.fl6_dst, final_p);
643 
644 		if ((err = xfrm_lookup(sock_net(sk), &dst, &fl, sk, 0)) < 0) {
645 			sk->sk_err_soft = -err;
646 			return err;
647 		}
648 
649 		__ip6_dst_store(sk, dst, NULL, NULL);
650 	}
651 
652 	return 0;
653 }
654 
655 EXPORT_SYMBOL_GPL(inet6_sk_rebuild_header);
656 
657 int ipv6_opt_accepted(struct sock *sk, struct sk_buff *skb)
658 {
659 	struct ipv6_pinfo *np = inet6_sk(sk);
660 	struct inet6_skb_parm *opt = IP6CB(skb);
661 
662 	if (np->rxopt.all) {
663 		if ((opt->hop && (np->rxopt.bits.hopopts ||
664 				  np->rxopt.bits.ohopopts)) ||
665 		    ((IPV6_FLOWINFO_MASK &
666 		      *(__be32 *)skb_network_header(skb)) &&
667 		     np->rxopt.bits.rxflow) ||
668 		    (opt->srcrt && (np->rxopt.bits.srcrt ||
669 		     np->rxopt.bits.osrcrt)) ||
670 		    ((opt->dst1 || opt->dst0) &&
671 		     (np->rxopt.bits.dstopts || np->rxopt.bits.odstopts)))
672 			return 1;
673 	}
674 	return 0;
675 }
676 
677 EXPORT_SYMBOL_GPL(ipv6_opt_accepted);
678 
679 static int ipv6_gso_pull_exthdrs(struct sk_buff *skb, int proto)
680 {
681 	struct inet6_protocol *ops = NULL;
682 
683 	for (;;) {
684 		struct ipv6_opt_hdr *opth;
685 		int len;
686 
687 		if (proto != NEXTHDR_HOP) {
688 			ops = rcu_dereference(inet6_protos[proto]);
689 
690 			if (unlikely(!ops))
691 				break;
692 
693 			if (!(ops->flags & INET6_PROTO_GSO_EXTHDR))
694 				break;
695 		}
696 
697 		if (unlikely(!pskb_may_pull(skb, 8)))
698 			break;
699 
700 		opth = (void *)skb->data;
701 		len = ipv6_optlen(opth);
702 
703 		if (unlikely(!pskb_may_pull(skb, len)))
704 			break;
705 
706 		proto = opth->nexthdr;
707 		__skb_pull(skb, len);
708 	}
709 
710 	return proto;
711 }
712 
713 static int ipv6_gso_send_check(struct sk_buff *skb)
714 {
715 	struct ipv6hdr *ipv6h;
716 	struct inet6_protocol *ops;
717 	int err = -EINVAL;
718 
719 	if (unlikely(!pskb_may_pull(skb, sizeof(*ipv6h))))
720 		goto out;
721 
722 	ipv6h = ipv6_hdr(skb);
723 	__skb_pull(skb, sizeof(*ipv6h));
724 	err = -EPROTONOSUPPORT;
725 
726 	rcu_read_lock();
727 	ops = rcu_dereference(inet6_protos[
728 		ipv6_gso_pull_exthdrs(skb, ipv6h->nexthdr)]);
729 
730 	if (likely(ops && ops->gso_send_check)) {
731 		skb_reset_transport_header(skb);
732 		err = ops->gso_send_check(skb);
733 	}
734 	rcu_read_unlock();
735 
736 out:
737 	return err;
738 }
739 
740 static struct sk_buff *ipv6_gso_segment(struct sk_buff *skb, int features)
741 {
742 	struct sk_buff *segs = ERR_PTR(-EINVAL);
743 	struct ipv6hdr *ipv6h;
744 	struct inet6_protocol *ops;
745 
746 	if (!(features & NETIF_F_V6_CSUM))
747 		features &= ~NETIF_F_SG;
748 
749 	if (unlikely(skb_shinfo(skb)->gso_type &
750 		     ~(SKB_GSO_UDP |
751 		       SKB_GSO_DODGY |
752 		       SKB_GSO_TCP_ECN |
753 		       SKB_GSO_TCPV6 |
754 		       0)))
755 		goto out;
756 
757 	if (unlikely(!pskb_may_pull(skb, sizeof(*ipv6h))))
758 		goto out;
759 
760 	ipv6h = ipv6_hdr(skb);
761 	__skb_pull(skb, sizeof(*ipv6h));
762 	segs = ERR_PTR(-EPROTONOSUPPORT);
763 
764 	rcu_read_lock();
765 	ops = rcu_dereference(inet6_protos[
766 		ipv6_gso_pull_exthdrs(skb, ipv6h->nexthdr)]);
767 
768 	if (likely(ops && ops->gso_segment)) {
769 		skb_reset_transport_header(skb);
770 		segs = ops->gso_segment(skb, features);
771 	}
772 	rcu_read_unlock();
773 
774 	if (unlikely(IS_ERR(segs)))
775 		goto out;
776 
777 	for (skb = segs; skb; skb = skb->next) {
778 		ipv6h = ipv6_hdr(skb);
779 		ipv6h->payload_len = htons(skb->len - skb->mac_len -
780 					   sizeof(*ipv6h));
781 	}
782 
783 out:
784 	return segs;
785 }
786 
787 struct ipv6_gro_cb {
788 	struct napi_gro_cb napi;
789 	int proto;
790 };
791 
792 #define IPV6_GRO_CB(skb) ((struct ipv6_gro_cb *)(skb)->cb)
793 
794 static struct sk_buff **ipv6_gro_receive(struct sk_buff **head,
795 					 struct sk_buff *skb)
796 {
797 	struct inet6_protocol *ops;
798 	struct sk_buff **pp = NULL;
799 	struct sk_buff *p;
800 	struct ipv6hdr *iph;
801 	unsigned int nlen;
802 	int flush = 1;
803 	int proto;
804 	__wsum csum;
805 
806 	if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
807 		goto out;
808 
809 	iph = ipv6_hdr(skb);
810 	__skb_pull(skb, sizeof(*iph));
811 
812 	flush += ntohs(iph->payload_len) != skb->len;
813 
814 	rcu_read_lock();
815 	proto = ipv6_gso_pull_exthdrs(skb, iph->nexthdr);
816 	iph = ipv6_hdr(skb);
817 	IPV6_GRO_CB(skb)->proto = proto;
818 	ops = rcu_dereference(inet6_protos[proto]);
819 	if (!ops || !ops->gro_receive)
820 		goto out_unlock;
821 
822 	flush--;
823 	skb_reset_transport_header(skb);
824 	nlen = skb_network_header_len(skb);
825 
826 	for (p = *head; p; p = p->next) {
827 		struct ipv6hdr *iph2;
828 
829 		if (!NAPI_GRO_CB(p)->same_flow)
830 			continue;
831 
832 		iph2 = ipv6_hdr(p);
833 
834 		/* All fields must match except length. */
835 		if (nlen != skb_network_header_len(p) ||
836 		    memcmp(iph, iph2, offsetof(struct ipv6hdr, payload_len)) ||
837 		    memcmp(&iph->nexthdr, &iph2->nexthdr,
838 			   nlen - offsetof(struct ipv6hdr, nexthdr))) {
839 			NAPI_GRO_CB(p)->same_flow = 0;
840 			continue;
841 		}
842 
843 		NAPI_GRO_CB(p)->flush |= flush;
844 	}
845 
846 	NAPI_GRO_CB(skb)->flush |= flush;
847 
848 	csum = skb->csum;
849 	skb_postpull_rcsum(skb, iph, skb_network_header_len(skb));
850 
851 	pp = ops->gro_receive(head, skb);
852 
853 	skb->csum = csum;
854 
855 out_unlock:
856 	rcu_read_unlock();
857 
858 out:
859 	NAPI_GRO_CB(skb)->flush |= flush;
860 
861 	return pp;
862 }
863 
864 static int ipv6_gro_complete(struct sk_buff *skb)
865 {
866 	struct inet6_protocol *ops;
867 	struct ipv6hdr *iph = ipv6_hdr(skb);
868 	int err = -ENOSYS;
869 
870 	iph->payload_len = htons(skb->len - skb_network_offset(skb) -
871 				 sizeof(*iph));
872 
873 	rcu_read_lock();
874 	ops = rcu_dereference(inet6_protos[IPV6_GRO_CB(skb)->proto]);
875 	if (WARN_ON(!ops || !ops->gro_complete))
876 		goto out_unlock;
877 
878 	err = ops->gro_complete(skb);
879 
880 out_unlock:
881 	rcu_read_unlock();
882 
883 	return err;
884 }
885 
886 static struct packet_type ipv6_packet_type = {
887 	.type = __constant_htons(ETH_P_IPV6),
888 	.func = ipv6_rcv,
889 	.gso_send_check = ipv6_gso_send_check,
890 	.gso_segment = ipv6_gso_segment,
891 	.gro_receive = ipv6_gro_receive,
892 	.gro_complete = ipv6_gro_complete,
893 };
894 
895 static int __init ipv6_packet_init(void)
896 {
897 	dev_add_pack(&ipv6_packet_type);
898 	return 0;
899 }
900 
901 static void ipv6_packet_cleanup(void)
902 {
903 	dev_remove_pack(&ipv6_packet_type);
904 }
905 
906 static int __net_init ipv6_init_mibs(struct net *net)
907 {
908 	if (snmp_mib_init((void **)net->mib.udp_stats_in6,
909 			  sizeof (struct udp_mib)) < 0)
910 		return -ENOMEM;
911 	if (snmp_mib_init((void **)net->mib.udplite_stats_in6,
912 			  sizeof (struct udp_mib)) < 0)
913 		goto err_udplite_mib;
914 	if (snmp_mib_init((void **)net->mib.ipv6_statistics,
915 			  sizeof(struct ipstats_mib)) < 0)
916 		goto err_ip_mib;
917 	if (snmp_mib_init((void **)net->mib.icmpv6_statistics,
918 			  sizeof(struct icmpv6_mib)) < 0)
919 		goto err_icmp_mib;
920 	if (snmp_mib_init((void **)net->mib.icmpv6msg_statistics,
921 			  sizeof(struct icmpv6msg_mib)) < 0)
922 		goto err_icmpmsg_mib;
923 	return 0;
924 
925 err_icmpmsg_mib:
926 	snmp_mib_free((void **)net->mib.icmpv6_statistics);
927 err_icmp_mib:
928 	snmp_mib_free((void **)net->mib.ipv6_statistics);
929 err_ip_mib:
930 	snmp_mib_free((void **)net->mib.udplite_stats_in6);
931 err_udplite_mib:
932 	snmp_mib_free((void **)net->mib.udp_stats_in6);
933 	return -ENOMEM;
934 }
935 
936 static void __net_exit ipv6_cleanup_mibs(struct net *net)
937 {
938 	snmp_mib_free((void **)net->mib.udp_stats_in6);
939 	snmp_mib_free((void **)net->mib.udplite_stats_in6);
940 	snmp_mib_free((void **)net->mib.ipv6_statistics);
941 	snmp_mib_free((void **)net->mib.icmpv6_statistics);
942 	snmp_mib_free((void **)net->mib.icmpv6msg_statistics);
943 }
944 
945 static int __net_init inet6_net_init(struct net *net)
946 {
947 	int err = 0;
948 
949 	net->ipv6.sysctl.bindv6only = 0;
950 	net->ipv6.sysctl.icmpv6_time = 1*HZ;
951 
952 	err = ipv6_init_mibs(net);
953 	if (err)
954 		return err;
955 #ifdef CONFIG_PROC_FS
956 	err = udp6_proc_init(net);
957 	if (err)
958 		goto out;
959 	err = tcp6_proc_init(net);
960 	if (err)
961 		goto proc_tcp6_fail;
962 	err = ac6_proc_init(net);
963 	if (err)
964 		goto proc_ac6_fail;
965 #endif
966 	return err;
967 
968 #ifdef CONFIG_PROC_FS
969 proc_ac6_fail:
970 	tcp6_proc_exit(net);
971 proc_tcp6_fail:
972 	udp6_proc_exit(net);
973 out:
974 	ipv6_cleanup_mibs(net);
975 	return err;
976 #endif
977 }
978 
979 static void inet6_net_exit(struct net *net)
980 {
981 #ifdef CONFIG_PROC_FS
982 	udp6_proc_exit(net);
983 	tcp6_proc_exit(net);
984 	ac6_proc_exit(net);
985 #endif
986 	ipv6_cleanup_mibs(net);
987 }
988 
989 static struct pernet_operations inet6_net_ops = {
990 	.init = inet6_net_init,
991 	.exit = inet6_net_exit,
992 };
993 
994 static int __init inet6_init(void)
995 {
996 	struct sk_buff *dummy_skb;
997 	struct list_head *r;
998 	int err = 0;
999 
1000 	BUILD_BUG_ON(sizeof(struct inet6_skb_parm) > sizeof(dummy_skb->cb));
1001 
1002 	/* Register the socket-side information for inet6_create.  */
1003 	for(r = &inetsw6[0]; r < &inetsw6[SOCK_MAX]; ++r)
1004 		INIT_LIST_HEAD(r);
1005 
1006 	if (disable_ipv6) {
1007 		printk(KERN_INFO
1008 		       "IPv6: Loaded, but administratively disabled, "
1009 		       "reboot required to enable\n");
1010 		goto out;
1011 	}
1012 
1013 	err = proto_register(&tcpv6_prot, 1);
1014 	if (err)
1015 		goto out;
1016 
1017 	err = proto_register(&udpv6_prot, 1);
1018 	if (err)
1019 		goto out_unregister_tcp_proto;
1020 
1021 	err = proto_register(&udplitev6_prot, 1);
1022 	if (err)
1023 		goto out_unregister_udp_proto;
1024 
1025 	err = proto_register(&rawv6_prot, 1);
1026 	if (err)
1027 		goto out_unregister_udplite_proto;
1028 
1029 
1030 	/* We MUST register RAW sockets before we create the ICMP6,
1031 	 * IGMP6, or NDISC control sockets.
1032 	 */
1033 	err = rawv6_init();
1034 	if (err)
1035 		goto out_unregister_raw_proto;
1036 
1037 	/* Register the family here so that the init calls below will
1038 	 * be able to create sockets. (?? is this dangerous ??)
1039 	 */
1040 	err = sock_register(&inet6_family_ops);
1041 	if (err)
1042 		goto out_sock_register_fail;
1043 
1044 #ifdef CONFIG_SYSCTL
1045 	err = ipv6_static_sysctl_register();
1046 	if (err)
1047 		goto static_sysctl_fail;
1048 #endif
1049 	/*
1050 	 *	ipngwg API draft makes clear that the correct semantics
1051 	 *	for TCP and UDP is to consider one TCP and UDP instance
1052 	 *	in a host availiable by both INET and INET6 APIs and
1053 	 *	able to communicate via both network protocols.
1054 	 */
1055 
1056 	err = register_pernet_subsys(&inet6_net_ops);
1057 	if (err)
1058 		goto register_pernet_fail;
1059 	err = icmpv6_init();
1060 	if (err)
1061 		goto icmp_fail;
1062 	err = ip6_mr_init();
1063 	if (err)
1064 		goto ipmr_fail;
1065 	err = ndisc_init();
1066 	if (err)
1067 		goto ndisc_fail;
1068 	err = igmp6_init();
1069 	if (err)
1070 		goto igmp_fail;
1071 	err = ipv6_netfilter_init();
1072 	if (err)
1073 		goto netfilter_fail;
1074 	/* Create /proc/foo6 entries. */
1075 #ifdef CONFIG_PROC_FS
1076 	err = -ENOMEM;
1077 	if (raw6_proc_init())
1078 		goto proc_raw6_fail;
1079 	if (udplite6_proc_init())
1080 		goto proc_udplite6_fail;
1081 	if (ipv6_misc_proc_init())
1082 		goto proc_misc6_fail;
1083 	if (if6_proc_init())
1084 		goto proc_if6_fail;
1085 #endif
1086 	err = ip6_route_init();
1087 	if (err)
1088 		goto ip6_route_fail;
1089 	err = ip6_flowlabel_init();
1090 	if (err)
1091 		goto ip6_flowlabel_fail;
1092 	err = addrconf_init();
1093 	if (err)
1094 		goto addrconf_fail;
1095 
1096 	/* Init v6 extension headers. */
1097 	err = ipv6_exthdrs_init();
1098 	if (err)
1099 		goto ipv6_exthdrs_fail;
1100 
1101 	err = ipv6_frag_init();
1102 	if (err)
1103 		goto ipv6_frag_fail;
1104 
1105 	/* Init v6 transport protocols. */
1106 	err = udpv6_init();
1107 	if (err)
1108 		goto udpv6_fail;
1109 
1110 	err = udplitev6_init();
1111 	if (err)
1112 		goto udplitev6_fail;
1113 
1114 	err = tcpv6_init();
1115 	if (err)
1116 		goto tcpv6_fail;
1117 
1118 	err = ipv6_packet_init();
1119 	if (err)
1120 		goto ipv6_packet_fail;
1121 
1122 #ifdef CONFIG_SYSCTL
1123 	err = ipv6_sysctl_register();
1124 	if (err)
1125 		goto sysctl_fail;
1126 #endif
1127 out:
1128 	return err;
1129 
1130 #ifdef CONFIG_SYSCTL
1131 sysctl_fail:
1132 	ipv6_packet_cleanup();
1133 #endif
1134 ipv6_packet_fail:
1135 	tcpv6_exit();
1136 tcpv6_fail:
1137 	udplitev6_exit();
1138 udplitev6_fail:
1139 	udpv6_exit();
1140 udpv6_fail:
1141 	ipv6_frag_exit();
1142 ipv6_frag_fail:
1143 	ipv6_exthdrs_exit();
1144 ipv6_exthdrs_fail:
1145 	addrconf_cleanup();
1146 addrconf_fail:
1147 	ip6_flowlabel_cleanup();
1148 ip6_flowlabel_fail:
1149 	ip6_route_cleanup();
1150 ip6_route_fail:
1151 #ifdef CONFIG_PROC_FS
1152 	if6_proc_exit();
1153 proc_if6_fail:
1154 	ipv6_misc_proc_exit();
1155 proc_misc6_fail:
1156 	udplite6_proc_exit();
1157 proc_udplite6_fail:
1158 	raw6_proc_exit();
1159 proc_raw6_fail:
1160 #endif
1161 	ipv6_netfilter_fini();
1162 netfilter_fail:
1163 	igmp6_cleanup();
1164 igmp_fail:
1165 	ndisc_cleanup();
1166 ndisc_fail:
1167 	ip6_mr_cleanup();
1168 ipmr_fail:
1169 	icmpv6_cleanup();
1170 icmp_fail:
1171 	unregister_pernet_subsys(&inet6_net_ops);
1172 register_pernet_fail:
1173 #ifdef CONFIG_SYSCTL
1174 	ipv6_static_sysctl_unregister();
1175 static_sysctl_fail:
1176 #endif
1177 	sock_unregister(PF_INET6);
1178 	rtnl_unregister_all(PF_INET6);
1179 out_sock_register_fail:
1180 	rawv6_exit();
1181 out_unregister_raw_proto:
1182 	proto_unregister(&rawv6_prot);
1183 out_unregister_udplite_proto:
1184 	proto_unregister(&udplitev6_prot);
1185 out_unregister_udp_proto:
1186 	proto_unregister(&udpv6_prot);
1187 out_unregister_tcp_proto:
1188 	proto_unregister(&tcpv6_prot);
1189 	goto out;
1190 }
1191 module_init(inet6_init);
1192 
1193 static void __exit inet6_exit(void)
1194 {
1195 	if (disable_ipv6)
1196 		return;
1197 
1198 	/* First of all disallow new sockets creation. */
1199 	sock_unregister(PF_INET6);
1200 	/* Disallow any further netlink messages */
1201 	rtnl_unregister_all(PF_INET6);
1202 
1203 #ifdef CONFIG_SYSCTL
1204 	ipv6_sysctl_unregister();
1205 #endif
1206 	udpv6_exit();
1207 	udplitev6_exit();
1208 	tcpv6_exit();
1209 
1210 	/* Cleanup code parts. */
1211 	ipv6_packet_cleanup();
1212 	ipv6_frag_exit();
1213 	ipv6_exthdrs_exit();
1214 	addrconf_cleanup();
1215 	ip6_flowlabel_cleanup();
1216 	ip6_route_cleanup();
1217 #ifdef CONFIG_PROC_FS
1218 
1219 	/* Cleanup code parts. */
1220 	if6_proc_exit();
1221 	ipv6_misc_proc_exit();
1222 	udplite6_proc_exit();
1223 	raw6_proc_exit();
1224 #endif
1225 	ipv6_netfilter_fini();
1226 	igmp6_cleanup();
1227 	ndisc_cleanup();
1228 	ip6_mr_cleanup();
1229 	icmpv6_cleanup();
1230 	rawv6_exit();
1231 
1232 	unregister_pernet_subsys(&inet6_net_ops);
1233 #ifdef CONFIG_SYSCTL
1234 	ipv6_static_sysctl_unregister();
1235 #endif
1236 	proto_unregister(&rawv6_prot);
1237 	proto_unregister(&udplitev6_prot);
1238 	proto_unregister(&udpv6_prot);
1239 	proto_unregister(&tcpv6_prot);
1240 }
1241 module_exit(inet6_exit);
1242 
1243 MODULE_ALIAS_NETPROTO(PF_INET6);
1244