xref: /linux/net/ipv6/af_inet6.c (revision 1fc31357ad194fb98691f3d122bcd47e59239e83)
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 #define pr_fmt(fmt) "IPv6: " fmt
22 
23 #include <linux/module.h>
24 #include <linux/capability.h>
25 #include <linux/errno.h>
26 #include <linux/types.h>
27 #include <linux/socket.h>
28 #include <linux/in.h>
29 #include <linux/kernel.h>
30 #include <linux/timer.h>
31 #include <linux/string.h>
32 #include <linux/sockios.h>
33 #include <linux/net.h>
34 #include <linux/fcntl.h>
35 #include <linux/mm.h>
36 #include <linux/interrupt.h>
37 #include <linux/proc_fs.h>
38 #include <linux/stat.h>
39 #include <linux/init.h>
40 #include <linux/slab.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/ping.h>
53 #include <net/protocol.h>
54 #include <net/inet_common.h>
55 #include <net/route.h>
56 #include <net/transp_v6.h>
57 #include <net/ip6_route.h>
58 #include <net/addrconf.h>
59 #include <net/ndisc.h>
60 #ifdef CONFIG_IPV6_TUNNEL
61 #include <net/ip6_tunnel.h>
62 #endif
63 #include <net/calipso.h>
64 #include <net/seg6.h>
65 
66 #include <asm/uaccess.h>
67 #include <linux/mroute6.h>
68 
69 #include "ip6_offload.h"
70 
71 MODULE_AUTHOR("Cast of dozens");
72 MODULE_DESCRIPTION("IPv6 protocol stack for Linux");
73 MODULE_LICENSE("GPL");
74 
75 /* The inetsw6 table contains everything that inet6_create needs to
76  * build a new socket.
77  */
78 static struct list_head inetsw6[SOCK_MAX];
79 static DEFINE_SPINLOCK(inetsw6_lock);
80 
81 struct ipv6_params ipv6_defaults = {
82 	.disable_ipv6 = 0,
83 	.autoconf = 1,
84 };
85 
86 static int disable_ipv6_mod;
87 
88 module_param_named(disable, disable_ipv6_mod, int, 0444);
89 MODULE_PARM_DESC(disable, "Disable IPv6 module such that it is non-functional");
90 
91 module_param_named(disable_ipv6, ipv6_defaults.disable_ipv6, int, 0444);
92 MODULE_PARM_DESC(disable_ipv6, "Disable IPv6 on all interfaces");
93 
94 module_param_named(autoconf, ipv6_defaults.autoconf, int, 0444);
95 MODULE_PARM_DESC(autoconf, "Enable IPv6 address autoconfiguration on all interfaces");
96 
97 bool ipv6_mod_enabled(void)
98 {
99 	return disable_ipv6_mod == 0;
100 }
101 EXPORT_SYMBOL_GPL(ipv6_mod_enabled);
102 
103 static __inline__ struct ipv6_pinfo *inet6_sk_generic(struct sock *sk)
104 {
105 	const int offset = sk->sk_prot->obj_size - sizeof(struct ipv6_pinfo);
106 
107 	return (struct ipv6_pinfo *)(((u8 *)sk) + offset);
108 }
109 
110 static int inet6_create(struct net *net, struct socket *sock, int protocol,
111 			int kern)
112 {
113 	struct inet_sock *inet;
114 	struct ipv6_pinfo *np;
115 	struct sock *sk;
116 	struct inet_protosw *answer;
117 	struct proto *answer_prot;
118 	unsigned char answer_flags;
119 	int try_loading_module = 0;
120 	int err;
121 
122 	if (protocol < 0 || protocol >= IPPROTO_MAX)
123 		return -EINVAL;
124 
125 	/* Look for the requested type/protocol pair. */
126 lookup_protocol:
127 	err = -ESOCKTNOSUPPORT;
128 	rcu_read_lock();
129 	list_for_each_entry_rcu(answer, &inetsw6[sock->type], list) {
130 
131 		err = 0;
132 		/* Check the non-wild match. */
133 		if (protocol == answer->protocol) {
134 			if (protocol != IPPROTO_IP)
135 				break;
136 		} else {
137 			/* Check for the two wild cases. */
138 			if (IPPROTO_IP == protocol) {
139 				protocol = answer->protocol;
140 				break;
141 			}
142 			if (IPPROTO_IP == answer->protocol)
143 				break;
144 		}
145 		err = -EPROTONOSUPPORT;
146 	}
147 
148 	if (err) {
149 		if (try_loading_module < 2) {
150 			rcu_read_unlock();
151 			/*
152 			 * Be more specific, e.g. net-pf-10-proto-132-type-1
153 			 * (net-pf-PF_INET6-proto-IPPROTO_SCTP-type-SOCK_STREAM)
154 			 */
155 			if (++try_loading_module == 1)
156 				request_module("net-pf-%d-proto-%d-type-%d",
157 						PF_INET6, protocol, sock->type);
158 			/*
159 			 * Fall back to generic, e.g. net-pf-10-proto-132
160 			 * (net-pf-PF_INET6-proto-IPPROTO_SCTP)
161 			 */
162 			else
163 				request_module("net-pf-%d-proto-%d",
164 						PF_INET6, protocol);
165 			goto lookup_protocol;
166 		} else
167 			goto out_rcu_unlock;
168 	}
169 
170 	err = -EPERM;
171 	if (sock->type == SOCK_RAW && !kern &&
172 	    !ns_capable(net->user_ns, CAP_NET_RAW))
173 		goto out_rcu_unlock;
174 
175 	sock->ops = answer->ops;
176 	answer_prot = answer->prot;
177 	answer_flags = answer->flags;
178 	rcu_read_unlock();
179 
180 	WARN_ON(!answer_prot->slab);
181 
182 	err = -ENOBUFS;
183 	sk = sk_alloc(net, PF_INET6, GFP_KERNEL, answer_prot, kern);
184 	if (!sk)
185 		goto out;
186 
187 	sock_init_data(sock, sk);
188 
189 	err = 0;
190 	if (INET_PROTOSW_REUSE & answer_flags)
191 		sk->sk_reuse = SK_CAN_REUSE;
192 
193 	inet = inet_sk(sk);
194 	inet->is_icsk = (INET_PROTOSW_ICSK & answer_flags) != 0;
195 
196 	if (SOCK_RAW == sock->type) {
197 		inet->inet_num = protocol;
198 		if (IPPROTO_RAW == protocol)
199 			inet->hdrincl = 1;
200 	}
201 
202 	sk->sk_destruct		= inet_sock_destruct;
203 	sk->sk_family		= PF_INET6;
204 	sk->sk_protocol		= protocol;
205 
206 	sk->sk_backlog_rcv	= answer->prot->backlog_rcv;
207 
208 	inet_sk(sk)->pinet6 = np = inet6_sk_generic(sk);
209 	np->hop_limit	= -1;
210 	np->mcast_hops	= IPV6_DEFAULT_MCASTHOPS;
211 	np->mc_loop	= 1;
212 	np->pmtudisc	= IPV6_PMTUDISC_WANT;
213 	np->autoflowlabel = ip6_default_np_autolabel(sock_net(sk));
214 	sk->sk_ipv6only	= net->ipv6.sysctl.bindv6only;
215 
216 	/* Init the ipv4 part of the socket since we can have sockets
217 	 * using v6 API for ipv4.
218 	 */
219 	inet->uc_ttl	= -1;
220 
221 	inet->mc_loop	= 1;
222 	inet->mc_ttl	= 1;
223 	inet->mc_index	= 0;
224 	inet->mc_list	= NULL;
225 	inet->rcv_tos	= 0;
226 
227 	if (net->ipv4.sysctl_ip_no_pmtu_disc)
228 		inet->pmtudisc = IP_PMTUDISC_DONT;
229 	else
230 		inet->pmtudisc = IP_PMTUDISC_WANT;
231 	/*
232 	 * Increment only the relevant sk_prot->socks debug field, this changes
233 	 * the previous behaviour of incrementing both the equivalent to
234 	 * answer->prot->socks (inet6_sock_nr) and inet_sock_nr.
235 	 *
236 	 * This allows better debug granularity as we'll know exactly how many
237 	 * UDPv6, TCPv6, etc socks were allocated, not the sum of all IPv6
238 	 * transport protocol socks. -acme
239 	 */
240 	sk_refcnt_debug_inc(sk);
241 
242 	if (inet->inet_num) {
243 		/* It assumes that any protocol which allows
244 		 * the user to assign a number at socket
245 		 * creation time automatically shares.
246 		 */
247 		inet->inet_sport = htons(inet->inet_num);
248 		err = sk->sk_prot->hash(sk);
249 		if (err) {
250 			sk_common_release(sk);
251 			goto out;
252 		}
253 	}
254 	if (sk->sk_prot->init) {
255 		err = sk->sk_prot->init(sk);
256 		if (err) {
257 			sk_common_release(sk);
258 			goto out;
259 		}
260 	}
261 out:
262 	return err;
263 out_rcu_unlock:
264 	rcu_read_unlock();
265 	goto out;
266 }
267 
268 
269 /* bind for INET6 API */
270 int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
271 {
272 	struct sockaddr_in6 *addr = (struct sockaddr_in6 *)uaddr;
273 	struct sock *sk = sock->sk;
274 	struct inet_sock *inet = inet_sk(sk);
275 	struct ipv6_pinfo *np = inet6_sk(sk);
276 	struct net *net = sock_net(sk);
277 	__be32 v4addr = 0;
278 	unsigned short snum;
279 	int addr_type = 0;
280 	int err = 0;
281 
282 	/* If the socket has its own bind function then use it. */
283 	if (sk->sk_prot->bind)
284 		return sk->sk_prot->bind(sk, uaddr, addr_len);
285 
286 	if (addr_len < SIN6_LEN_RFC2133)
287 		return -EINVAL;
288 
289 	if (addr->sin6_family != AF_INET6)
290 		return -EAFNOSUPPORT;
291 
292 	addr_type = ipv6_addr_type(&addr->sin6_addr);
293 	if ((addr_type & IPV6_ADDR_MULTICAST) && sock->type == SOCK_STREAM)
294 		return -EINVAL;
295 
296 	snum = ntohs(addr->sin6_port);
297 	if (snum && snum < PROT_SOCK && !ns_capable(net->user_ns, CAP_NET_BIND_SERVICE))
298 		return -EACCES;
299 
300 	lock_sock(sk);
301 
302 	/* Check these errors (active socket, double bind). */
303 	if (sk->sk_state != TCP_CLOSE || inet->inet_num) {
304 		err = -EINVAL;
305 		goto out;
306 	}
307 
308 	/* Check if the address belongs to the host. */
309 	if (addr_type == IPV6_ADDR_MAPPED) {
310 		int chk_addr_ret;
311 
312 		/* Binding to v4-mapped address on a v6-only socket
313 		 * makes no sense
314 		 */
315 		if (sk->sk_ipv6only) {
316 			err = -EINVAL;
317 			goto out;
318 		}
319 
320 		/* Reproduce AF_INET checks to make the bindings consistent */
321 		v4addr = addr->sin6_addr.s6_addr32[3];
322 		chk_addr_ret = inet_addr_type(net, v4addr);
323 		if (!net->ipv4.sysctl_ip_nonlocal_bind &&
324 		    !(inet->freebind || inet->transparent) &&
325 		    v4addr != htonl(INADDR_ANY) &&
326 		    chk_addr_ret != RTN_LOCAL &&
327 		    chk_addr_ret != RTN_MULTICAST &&
328 		    chk_addr_ret != RTN_BROADCAST) {
329 			err = -EADDRNOTAVAIL;
330 			goto out;
331 		}
332 	} else {
333 		if (addr_type != IPV6_ADDR_ANY) {
334 			struct net_device *dev = NULL;
335 
336 			rcu_read_lock();
337 			if (__ipv6_addr_needs_scope_id(addr_type)) {
338 				if (addr_len >= sizeof(struct sockaddr_in6) &&
339 				    addr->sin6_scope_id) {
340 					/* Override any existing binding, if another one
341 					 * is supplied by user.
342 					 */
343 					sk->sk_bound_dev_if = addr->sin6_scope_id;
344 				}
345 
346 				/* Binding to link-local address requires an interface */
347 				if (!sk->sk_bound_dev_if) {
348 					err = -EINVAL;
349 					goto out_unlock;
350 				}
351 				dev = dev_get_by_index_rcu(net, sk->sk_bound_dev_if);
352 				if (!dev) {
353 					err = -ENODEV;
354 					goto out_unlock;
355 				}
356 			}
357 
358 			/* ipv4 addr of the socket is invalid.  Only the
359 			 * unspecified and mapped address have a v4 equivalent.
360 			 */
361 			v4addr = LOOPBACK4_IPV6;
362 			if (!(addr_type & IPV6_ADDR_MULTICAST))	{
363 				if (!net->ipv6.sysctl.ip_nonlocal_bind &&
364 				    !(inet->freebind || inet->transparent) &&
365 				    !ipv6_chk_addr(net, &addr->sin6_addr,
366 						   dev, 0)) {
367 					err = -EADDRNOTAVAIL;
368 					goto out_unlock;
369 				}
370 			}
371 			rcu_read_unlock();
372 		}
373 	}
374 
375 	inet->inet_rcv_saddr = v4addr;
376 	inet->inet_saddr = v4addr;
377 
378 	sk->sk_v6_rcv_saddr = addr->sin6_addr;
379 
380 	if (!(addr_type & IPV6_ADDR_MULTICAST))
381 		np->saddr = addr->sin6_addr;
382 
383 	/* Make sure we are allowed to bind here. */
384 	if ((snum || !inet->bind_address_no_port) &&
385 	    sk->sk_prot->get_port(sk, snum)) {
386 		inet_reset_saddr(sk);
387 		err = -EADDRINUSE;
388 		goto out;
389 	}
390 
391 	if (addr_type != IPV6_ADDR_ANY) {
392 		sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
393 		if (addr_type != IPV6_ADDR_MAPPED)
394 			sk->sk_ipv6only = 1;
395 	}
396 	if (snum)
397 		sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
398 	inet->inet_sport = htons(inet->inet_num);
399 	inet->inet_dport = 0;
400 	inet->inet_daddr = 0;
401 out:
402 	release_sock(sk);
403 	return err;
404 out_unlock:
405 	rcu_read_unlock();
406 	goto out;
407 }
408 EXPORT_SYMBOL(inet6_bind);
409 
410 int inet6_release(struct socket *sock)
411 {
412 	struct sock *sk = sock->sk;
413 
414 	if (!sk)
415 		return -EINVAL;
416 
417 	/* Free mc lists */
418 	ipv6_sock_mc_close(sk);
419 
420 	/* Free ac lists */
421 	ipv6_sock_ac_close(sk);
422 
423 	return inet_release(sock);
424 }
425 EXPORT_SYMBOL(inet6_release);
426 
427 void inet6_destroy_sock(struct sock *sk)
428 {
429 	struct ipv6_pinfo *np = inet6_sk(sk);
430 	struct sk_buff *skb;
431 	struct ipv6_txoptions *opt;
432 
433 	/* Release rx options */
434 
435 	skb = xchg(&np->pktoptions, NULL);
436 	if (skb)
437 		kfree_skb(skb);
438 
439 	skb = xchg(&np->rxpmtu, NULL);
440 	if (skb)
441 		kfree_skb(skb);
442 
443 	/* Free flowlabels */
444 	fl6_free_socklist(sk);
445 
446 	/* Free tx options */
447 
448 	opt = xchg((__force struct ipv6_txoptions **)&np->opt, NULL);
449 	if (opt) {
450 		atomic_sub(opt->tot_len, &sk->sk_omem_alloc);
451 		txopt_put(opt);
452 	}
453 }
454 EXPORT_SYMBOL_GPL(inet6_destroy_sock);
455 
456 /*
457  *	This does both peername and sockname.
458  */
459 
460 int inet6_getname(struct socket *sock, struct sockaddr *uaddr,
461 		 int *uaddr_len, int peer)
462 {
463 	struct sockaddr_in6 *sin = (struct sockaddr_in6 *)uaddr;
464 	struct sock *sk = sock->sk;
465 	struct inet_sock *inet = inet_sk(sk);
466 	struct ipv6_pinfo *np = inet6_sk(sk);
467 
468 	sin->sin6_family = AF_INET6;
469 	sin->sin6_flowinfo = 0;
470 	sin->sin6_scope_id = 0;
471 	if (peer) {
472 		if (!inet->inet_dport)
473 			return -ENOTCONN;
474 		if (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
475 		    peer == 1)
476 			return -ENOTCONN;
477 		sin->sin6_port = inet->inet_dport;
478 		sin->sin6_addr = sk->sk_v6_daddr;
479 		if (np->sndflow)
480 			sin->sin6_flowinfo = np->flow_label;
481 	} else {
482 		if (ipv6_addr_any(&sk->sk_v6_rcv_saddr))
483 			sin->sin6_addr = np->saddr;
484 		else
485 			sin->sin6_addr = sk->sk_v6_rcv_saddr;
486 
487 		sin->sin6_port = inet->inet_sport;
488 	}
489 	sin->sin6_scope_id = ipv6_iface_scope_id(&sin->sin6_addr,
490 						 sk->sk_bound_dev_if);
491 	*uaddr_len = sizeof(*sin);
492 	return 0;
493 }
494 EXPORT_SYMBOL(inet6_getname);
495 
496 int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
497 {
498 	struct sock *sk = sock->sk;
499 	struct net *net = sock_net(sk);
500 
501 	switch (cmd) {
502 	case SIOCGSTAMP:
503 		return sock_get_timestamp(sk, (struct timeval __user *)arg);
504 
505 	case SIOCGSTAMPNS:
506 		return sock_get_timestampns(sk, (struct timespec __user *)arg);
507 
508 	case SIOCADDRT:
509 	case SIOCDELRT:
510 
511 		return ipv6_route_ioctl(net, cmd, (void __user *)arg);
512 
513 	case SIOCSIFADDR:
514 		return addrconf_add_ifaddr(net, (void __user *) arg);
515 	case SIOCDIFADDR:
516 		return addrconf_del_ifaddr(net, (void __user *) arg);
517 	case SIOCSIFDSTADDR:
518 		return addrconf_set_dstaddr(net, (void __user *) arg);
519 	default:
520 		if (!sk->sk_prot->ioctl)
521 			return -ENOIOCTLCMD;
522 		return sk->sk_prot->ioctl(sk, cmd, arg);
523 	}
524 	/*NOTREACHED*/
525 	return 0;
526 }
527 EXPORT_SYMBOL(inet6_ioctl);
528 
529 const struct proto_ops inet6_stream_ops = {
530 	.family		   = PF_INET6,
531 	.owner		   = THIS_MODULE,
532 	.release	   = inet6_release,
533 	.bind		   = inet6_bind,
534 	.connect	   = inet_stream_connect,	/* ok		*/
535 	.socketpair	   = sock_no_socketpair,	/* a do nothing	*/
536 	.accept		   = inet_accept,		/* ok		*/
537 	.getname	   = inet6_getname,
538 	.poll		   = tcp_poll,			/* ok		*/
539 	.ioctl		   = inet6_ioctl,		/* must change  */
540 	.listen		   = inet_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	   = inet_recvmsg,		/* ok		*/
546 	.mmap		   = sock_no_mmap,
547 	.sendpage	   = inet_sendpage,
548 	.splice_read	   = tcp_splice_read,
549 	.read_sock	   = tcp_read_sock,
550 	.peek_len	   = tcp_peek_len,
551 #ifdef CONFIG_COMPAT
552 	.compat_setsockopt = compat_sock_common_setsockopt,
553 	.compat_getsockopt = compat_sock_common_getsockopt,
554 #endif
555 };
556 
557 const struct proto_ops inet6_dgram_ops = {
558 	.family		   = PF_INET6,
559 	.owner		   = THIS_MODULE,
560 	.release	   = inet6_release,
561 	.bind		   = inet6_bind,
562 	.connect	   = inet_dgram_connect,	/* ok		*/
563 	.socketpair	   = sock_no_socketpair,	/* a do nothing	*/
564 	.accept		   = sock_no_accept,		/* a do nothing	*/
565 	.getname	   = inet6_getname,
566 	.poll		   = udp_poll,			/* ok		*/
567 	.ioctl		   = inet6_ioctl,		/* must change  */
568 	.listen		   = sock_no_listen,		/* ok		*/
569 	.shutdown	   = inet_shutdown,		/* ok		*/
570 	.setsockopt	   = sock_common_setsockopt,	/* ok		*/
571 	.getsockopt	   = sock_common_getsockopt,	/* ok		*/
572 	.sendmsg	   = inet_sendmsg,		/* ok		*/
573 	.recvmsg	   = inet_recvmsg,		/* ok		*/
574 	.mmap		   = sock_no_mmap,
575 	.sendpage	   = sock_no_sendpage,
576 	.set_peek_off	   = sk_set_peek_off,
577 #ifdef CONFIG_COMPAT
578 	.compat_setsockopt = compat_sock_common_setsockopt,
579 	.compat_getsockopt = compat_sock_common_getsockopt,
580 #endif
581 };
582 
583 static const struct net_proto_family inet6_family_ops = {
584 	.family = PF_INET6,
585 	.create = inet6_create,
586 	.owner	= THIS_MODULE,
587 };
588 
589 int inet6_register_protosw(struct inet_protosw *p)
590 {
591 	struct list_head *lh;
592 	struct inet_protosw *answer;
593 	struct list_head *last_perm;
594 	int protocol = p->protocol;
595 	int ret;
596 
597 	spin_lock_bh(&inetsw6_lock);
598 
599 	ret = -EINVAL;
600 	if (p->type >= SOCK_MAX)
601 		goto out_illegal;
602 
603 	/* If we are trying to override a permanent protocol, bail. */
604 	answer = NULL;
605 	ret = -EPERM;
606 	last_perm = &inetsw6[p->type];
607 	list_for_each(lh, &inetsw6[p->type]) {
608 		answer = list_entry(lh, struct inet_protosw, list);
609 
610 		/* Check only the non-wild match. */
611 		if (INET_PROTOSW_PERMANENT & answer->flags) {
612 			if (protocol == answer->protocol)
613 				break;
614 			last_perm = lh;
615 		}
616 
617 		answer = NULL;
618 	}
619 	if (answer)
620 		goto out_permanent;
621 
622 	/* Add the new entry after the last permanent entry if any, so that
623 	 * the new entry does not override a permanent entry when matched with
624 	 * a wild-card protocol. But it is allowed to override any existing
625 	 * non-permanent entry.  This means that when we remove this entry, the
626 	 * system automatically returns to the old behavior.
627 	 */
628 	list_add_rcu(&p->list, last_perm);
629 	ret = 0;
630 out:
631 	spin_unlock_bh(&inetsw6_lock);
632 	return ret;
633 
634 out_permanent:
635 	pr_err("Attempt to override permanent protocol %d\n", protocol);
636 	goto out;
637 
638 out_illegal:
639 	pr_err("Ignoring attempt to register invalid socket type %d\n",
640 	       p->type);
641 	goto out;
642 }
643 EXPORT_SYMBOL(inet6_register_protosw);
644 
645 void
646 inet6_unregister_protosw(struct inet_protosw *p)
647 {
648 	if (INET_PROTOSW_PERMANENT & p->flags) {
649 		pr_err("Attempt to unregister permanent protocol %d\n",
650 		       p->protocol);
651 	} else {
652 		spin_lock_bh(&inetsw6_lock);
653 		list_del_rcu(&p->list);
654 		spin_unlock_bh(&inetsw6_lock);
655 
656 		synchronize_net();
657 	}
658 }
659 EXPORT_SYMBOL(inet6_unregister_protosw);
660 
661 int inet6_sk_rebuild_header(struct sock *sk)
662 {
663 	struct ipv6_pinfo *np = inet6_sk(sk);
664 	struct dst_entry *dst;
665 
666 	dst = __sk_dst_check(sk, np->dst_cookie);
667 
668 	if (!dst) {
669 		struct inet_sock *inet = inet_sk(sk);
670 		struct in6_addr *final_p, final;
671 		struct flowi6 fl6;
672 
673 		memset(&fl6, 0, sizeof(fl6));
674 		fl6.flowi6_proto = sk->sk_protocol;
675 		fl6.daddr = sk->sk_v6_daddr;
676 		fl6.saddr = np->saddr;
677 		fl6.flowlabel = np->flow_label;
678 		fl6.flowi6_oif = sk->sk_bound_dev_if;
679 		fl6.flowi6_mark = sk->sk_mark;
680 		fl6.fl6_dport = inet->inet_dport;
681 		fl6.fl6_sport = inet->inet_sport;
682 		fl6.flowi6_uid = sk->sk_uid;
683 		security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
684 
685 		rcu_read_lock();
686 		final_p = fl6_update_dst(&fl6, rcu_dereference(np->opt),
687 					 &final);
688 		rcu_read_unlock();
689 
690 		dst = ip6_dst_lookup_flow(sk, &fl6, final_p);
691 		if (IS_ERR(dst)) {
692 			sk->sk_route_caps = 0;
693 			sk->sk_err_soft = -PTR_ERR(dst);
694 			return PTR_ERR(dst);
695 		}
696 
697 		ip6_dst_store(sk, dst, NULL, NULL);
698 	}
699 
700 	return 0;
701 }
702 EXPORT_SYMBOL_GPL(inet6_sk_rebuild_header);
703 
704 bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb,
705 		       const struct inet6_skb_parm *opt)
706 {
707 	const struct ipv6_pinfo *np = inet6_sk(sk);
708 
709 	if (np->rxopt.all) {
710 		if (((opt->flags & IP6SKB_HOPBYHOP) &&
711 		     (np->rxopt.bits.hopopts || np->rxopt.bits.ohopopts)) ||
712 		    (ip6_flowinfo((struct ipv6hdr *) skb_network_header(skb)) &&
713 		     np->rxopt.bits.rxflow) ||
714 		    (opt->srcrt && (np->rxopt.bits.srcrt ||
715 		     np->rxopt.bits.osrcrt)) ||
716 		    ((opt->dst1 || opt->dst0) &&
717 		     (np->rxopt.bits.dstopts || np->rxopt.bits.odstopts)))
718 			return true;
719 	}
720 	return false;
721 }
722 EXPORT_SYMBOL_GPL(ipv6_opt_accepted);
723 
724 static struct packet_type ipv6_packet_type __read_mostly = {
725 	.type = cpu_to_be16(ETH_P_IPV6),
726 	.func = ipv6_rcv,
727 };
728 
729 static int __init ipv6_packet_init(void)
730 {
731 	dev_add_pack(&ipv6_packet_type);
732 	return 0;
733 }
734 
735 static void ipv6_packet_cleanup(void)
736 {
737 	dev_remove_pack(&ipv6_packet_type);
738 }
739 
740 static int __net_init ipv6_init_mibs(struct net *net)
741 {
742 	int i;
743 
744 	net->mib.udp_stats_in6 = alloc_percpu(struct udp_mib);
745 	if (!net->mib.udp_stats_in6)
746 		return -ENOMEM;
747 	net->mib.udplite_stats_in6 = alloc_percpu(struct udp_mib);
748 	if (!net->mib.udplite_stats_in6)
749 		goto err_udplite_mib;
750 	net->mib.ipv6_statistics = alloc_percpu(struct ipstats_mib);
751 	if (!net->mib.ipv6_statistics)
752 		goto err_ip_mib;
753 
754 	for_each_possible_cpu(i) {
755 		struct ipstats_mib *af_inet6_stats;
756 		af_inet6_stats = per_cpu_ptr(net->mib.ipv6_statistics, i);
757 		u64_stats_init(&af_inet6_stats->syncp);
758 	}
759 
760 
761 	net->mib.icmpv6_statistics = alloc_percpu(struct icmpv6_mib);
762 	if (!net->mib.icmpv6_statistics)
763 		goto err_icmp_mib;
764 	net->mib.icmpv6msg_statistics = kzalloc(sizeof(struct icmpv6msg_mib),
765 						GFP_KERNEL);
766 	if (!net->mib.icmpv6msg_statistics)
767 		goto err_icmpmsg_mib;
768 	return 0;
769 
770 err_icmpmsg_mib:
771 	free_percpu(net->mib.icmpv6_statistics);
772 err_icmp_mib:
773 	free_percpu(net->mib.ipv6_statistics);
774 err_ip_mib:
775 	free_percpu(net->mib.udplite_stats_in6);
776 err_udplite_mib:
777 	free_percpu(net->mib.udp_stats_in6);
778 	return -ENOMEM;
779 }
780 
781 static void ipv6_cleanup_mibs(struct net *net)
782 {
783 	free_percpu(net->mib.udp_stats_in6);
784 	free_percpu(net->mib.udplite_stats_in6);
785 	free_percpu(net->mib.ipv6_statistics);
786 	free_percpu(net->mib.icmpv6_statistics);
787 	kfree(net->mib.icmpv6msg_statistics);
788 }
789 
790 static int __net_init inet6_net_init(struct net *net)
791 {
792 	int err = 0;
793 
794 	net->ipv6.sysctl.bindv6only = 0;
795 	net->ipv6.sysctl.icmpv6_time = 1*HZ;
796 	net->ipv6.sysctl.flowlabel_consistency = 1;
797 	net->ipv6.sysctl.auto_flowlabels = IP6_DEFAULT_AUTO_FLOW_LABELS;
798 	net->ipv6.sysctl.idgen_retries = 3;
799 	net->ipv6.sysctl.idgen_delay = 1 * HZ;
800 	net->ipv6.sysctl.flowlabel_state_ranges = 0;
801 	atomic_set(&net->ipv6.fib6_sernum, 1);
802 
803 	err = ipv6_init_mibs(net);
804 	if (err)
805 		return err;
806 #ifdef CONFIG_PROC_FS
807 	err = udp6_proc_init(net);
808 	if (err)
809 		goto out;
810 	err = tcp6_proc_init(net);
811 	if (err)
812 		goto proc_tcp6_fail;
813 	err = ac6_proc_init(net);
814 	if (err)
815 		goto proc_ac6_fail;
816 #endif
817 	return err;
818 
819 #ifdef CONFIG_PROC_FS
820 proc_ac6_fail:
821 	tcp6_proc_exit(net);
822 proc_tcp6_fail:
823 	udp6_proc_exit(net);
824 out:
825 	ipv6_cleanup_mibs(net);
826 	return err;
827 #endif
828 }
829 
830 static void __net_exit inet6_net_exit(struct net *net)
831 {
832 #ifdef CONFIG_PROC_FS
833 	udp6_proc_exit(net);
834 	tcp6_proc_exit(net);
835 	ac6_proc_exit(net);
836 #endif
837 	ipv6_cleanup_mibs(net);
838 }
839 
840 static struct pernet_operations inet6_net_ops = {
841 	.init = inet6_net_init,
842 	.exit = inet6_net_exit,
843 };
844 
845 static const struct ipv6_stub ipv6_stub_impl = {
846 	.ipv6_sock_mc_join = ipv6_sock_mc_join,
847 	.ipv6_sock_mc_drop = ipv6_sock_mc_drop,
848 	.ipv6_dst_lookup = ip6_dst_lookup,
849 	.udpv6_encap_enable = udpv6_encap_enable,
850 	.ndisc_send_na = ndisc_send_na,
851 	.nd_tbl	= &nd_tbl,
852 };
853 
854 static int __init inet6_init(void)
855 {
856 	struct list_head *r;
857 	int err = 0;
858 
859 	sock_skb_cb_check_size(sizeof(struct inet6_skb_parm));
860 
861 	/* Register the socket-side information for inet6_create.  */
862 	for (r = &inetsw6[0]; r < &inetsw6[SOCK_MAX]; ++r)
863 		INIT_LIST_HEAD(r);
864 
865 	if (disable_ipv6_mod) {
866 		pr_info("Loaded, but administratively disabled, reboot required to enable\n");
867 		goto out;
868 	}
869 
870 	err = proto_register(&tcpv6_prot, 1);
871 	if (err)
872 		goto out;
873 
874 	err = proto_register(&udpv6_prot, 1);
875 	if (err)
876 		goto out_unregister_tcp_proto;
877 
878 	err = proto_register(&udplitev6_prot, 1);
879 	if (err)
880 		goto out_unregister_udp_proto;
881 
882 	err = proto_register(&rawv6_prot, 1);
883 	if (err)
884 		goto out_unregister_udplite_proto;
885 
886 	err = proto_register(&pingv6_prot, 1);
887 	if (err)
888 		goto out_unregister_ping_proto;
889 
890 	/* We MUST register RAW sockets before we create the ICMP6,
891 	 * IGMP6, or NDISC control sockets.
892 	 */
893 	err = rawv6_init();
894 	if (err)
895 		goto out_unregister_raw_proto;
896 
897 	/* Register the family here so that the init calls below will
898 	 * be able to create sockets. (?? is this dangerous ??)
899 	 */
900 	err = sock_register(&inet6_family_ops);
901 	if (err)
902 		goto out_sock_register_fail;
903 
904 	/*
905 	 *	ipngwg API draft makes clear that the correct semantics
906 	 *	for TCP and UDP is to consider one TCP and UDP instance
907 	 *	in a host available by both INET and INET6 APIs and
908 	 *	able to communicate via both network protocols.
909 	 */
910 
911 	err = register_pernet_subsys(&inet6_net_ops);
912 	if (err)
913 		goto register_pernet_fail;
914 	err = icmpv6_init();
915 	if (err)
916 		goto icmp_fail;
917 	err = ip6_mr_init();
918 	if (err)
919 		goto ipmr_fail;
920 	err = ndisc_init();
921 	if (err)
922 		goto ndisc_fail;
923 	err = igmp6_init();
924 	if (err)
925 		goto igmp_fail;
926 
927 	ipv6_stub = &ipv6_stub_impl;
928 
929 	err = ipv6_netfilter_init();
930 	if (err)
931 		goto netfilter_fail;
932 	/* Create /proc/foo6 entries. */
933 #ifdef CONFIG_PROC_FS
934 	err = -ENOMEM;
935 	if (raw6_proc_init())
936 		goto proc_raw6_fail;
937 	if (udplite6_proc_init())
938 		goto proc_udplite6_fail;
939 	if (ipv6_misc_proc_init())
940 		goto proc_misc6_fail;
941 	if (if6_proc_init())
942 		goto proc_if6_fail;
943 #endif
944 	err = ip6_route_init();
945 	if (err)
946 		goto ip6_route_fail;
947 	err = ndisc_late_init();
948 	if (err)
949 		goto ndisc_late_fail;
950 	err = ip6_flowlabel_init();
951 	if (err)
952 		goto ip6_flowlabel_fail;
953 	err = addrconf_init();
954 	if (err)
955 		goto addrconf_fail;
956 
957 	/* Init v6 extension headers. */
958 	err = ipv6_exthdrs_init();
959 	if (err)
960 		goto ipv6_exthdrs_fail;
961 
962 	err = ipv6_frag_init();
963 	if (err)
964 		goto ipv6_frag_fail;
965 
966 	/* Init v6 transport protocols. */
967 	err = udpv6_init();
968 	if (err)
969 		goto udpv6_fail;
970 
971 	err = udplitev6_init();
972 	if (err)
973 		goto udplitev6_fail;
974 
975 	err = udpv6_offload_init();
976 	if (err)
977 		goto udpv6_offload_fail;
978 
979 	err = tcpv6_init();
980 	if (err)
981 		goto tcpv6_fail;
982 
983 	err = ipv6_packet_init();
984 	if (err)
985 		goto ipv6_packet_fail;
986 
987 	err = pingv6_init();
988 	if (err)
989 		goto pingv6_fail;
990 
991 	err = calipso_init();
992 	if (err)
993 		goto calipso_fail;
994 
995 	err = seg6_init();
996 	if (err)
997 		goto seg6_fail;
998 
999 #ifdef CONFIG_SYSCTL
1000 	err = ipv6_sysctl_register();
1001 	if (err)
1002 		goto sysctl_fail;
1003 #endif
1004 out:
1005 	return err;
1006 
1007 #ifdef CONFIG_SYSCTL
1008 sysctl_fail:
1009 	seg6_exit();
1010 #endif
1011 seg6_fail:
1012 	calipso_exit();
1013 calipso_fail:
1014 	pingv6_exit();
1015 pingv6_fail:
1016 	ipv6_packet_cleanup();
1017 ipv6_packet_fail:
1018 	tcpv6_exit();
1019 tcpv6_fail:
1020 	udpv6_offload_exit();
1021 udpv6_offload_fail:
1022 	udplitev6_exit();
1023 udplitev6_fail:
1024 	udpv6_exit();
1025 udpv6_fail:
1026 	ipv6_frag_exit();
1027 ipv6_frag_fail:
1028 	ipv6_exthdrs_exit();
1029 ipv6_exthdrs_fail:
1030 	addrconf_cleanup();
1031 addrconf_fail:
1032 	ip6_flowlabel_cleanup();
1033 ip6_flowlabel_fail:
1034 	ndisc_late_cleanup();
1035 ndisc_late_fail:
1036 	ip6_route_cleanup();
1037 ip6_route_fail:
1038 #ifdef CONFIG_PROC_FS
1039 	if6_proc_exit();
1040 proc_if6_fail:
1041 	ipv6_misc_proc_exit();
1042 proc_misc6_fail:
1043 	udplite6_proc_exit();
1044 proc_udplite6_fail:
1045 	raw6_proc_exit();
1046 proc_raw6_fail:
1047 #endif
1048 	ipv6_netfilter_fini();
1049 netfilter_fail:
1050 	igmp6_cleanup();
1051 igmp_fail:
1052 	ndisc_cleanup();
1053 ndisc_fail:
1054 	ip6_mr_cleanup();
1055 ipmr_fail:
1056 	icmpv6_cleanup();
1057 icmp_fail:
1058 	unregister_pernet_subsys(&inet6_net_ops);
1059 register_pernet_fail:
1060 	sock_unregister(PF_INET6);
1061 	rtnl_unregister_all(PF_INET6);
1062 out_sock_register_fail:
1063 	rawv6_exit();
1064 out_unregister_ping_proto:
1065 	proto_unregister(&pingv6_prot);
1066 out_unregister_raw_proto:
1067 	proto_unregister(&rawv6_prot);
1068 out_unregister_udplite_proto:
1069 	proto_unregister(&udplitev6_prot);
1070 out_unregister_udp_proto:
1071 	proto_unregister(&udpv6_prot);
1072 out_unregister_tcp_proto:
1073 	proto_unregister(&tcpv6_prot);
1074 	goto out;
1075 }
1076 module_init(inet6_init);
1077 
1078 MODULE_ALIAS_NETPROTO(PF_INET6);
1079