af_inet6.c revision c349a528cd47e2272ded0ea358363855e86180da 
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#include <linux/slab.h>
40
41#include <linux/inet.h>
42#include <linux/netdevice.h>
43#include <linux/icmpv6.h>
44#include <linux/netfilter_ipv6.h>
45
46#include <net/ip.h>
47#include <net/ipv6.h>
48#include <net/udp.h>
49#include <net/udplite.h>
50#include <net/tcp.h>
51#include <net/ipip.h>
52#include <net/protocol.h>
53#include <net/inet_common.h>
54#include <net/route.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#include <linux/mroute6.h>
65
66MODULE_AUTHOR("Cast of dozens");
67MODULE_DESCRIPTION("IPv6 protocol stack for Linux");
68MODULE_LICENSE("GPL");
69
70/* The inetsw6 table contains everything that inet6_create needs to
71 * build a new socket.
72 */
73static struct list_head inetsw6[SOCK_MAX];
74static DEFINE_SPINLOCK(inetsw6_lock);
75
76struct ipv6_params ipv6_defaults = {
77	.disable_ipv6 = 0,
78	.autoconf = 1,
79};
80
81static int disable_ipv6_mod = 0;
82
83module_param_named(disable, disable_ipv6_mod, int, 0444);
84MODULE_PARM_DESC(disable, "Disable IPv6 module such that it is non-functional");
85
86module_param_named(disable_ipv6, ipv6_defaults.disable_ipv6, int, 0444);
87MODULE_PARM_DESC(disable_ipv6, "Disable IPv6 on all interfaces");
88
89module_param_named(autoconf, ipv6_defaults.autoconf, int, 0444);
90MODULE_PARM_DESC(autoconf, "Enable IPv6 address autoconfiguration on all interfaces");
91
92static __inline__ struct ipv6_pinfo *inet6_sk_generic(struct sock *sk)
93{
94	const int offset = sk->sk_prot->obj_size - sizeof(struct ipv6_pinfo);
95
96	return (struct ipv6_pinfo *)(((u8 *)sk) + offset);
97}
98
99static int inet6_create(struct net *net, struct socket *sock, int protocol,
100			int kern)
101{
102	struct inet_sock *inet;
103	struct ipv6_pinfo *np;
104	struct sock *sk;
105	struct inet_protosw *answer;
106	struct proto *answer_prot;
107	unsigned char answer_flags;
108	char answer_no_check;
109	int try_loading_module = 0;
110	int err;
111
112	if (sock->type != SOCK_RAW &&
113	    sock->type != SOCK_DGRAM &&
114	    !inet_ehash_secret)
115		build_ehash_secret();
116
117	/* Look for the requested type/protocol pair. */
118lookup_protocol:
119	err = -ESOCKTNOSUPPORT;
120	rcu_read_lock();
121	list_for_each_entry_rcu(answer, &inetsw6[sock->type], list) {
122
123		err = 0;
124		/* Check the non-wild match. */
125		if (protocol == answer->protocol) {
126			if (protocol != IPPROTO_IP)
127				break;
128		} else {
129			/* Check for the two wild cases. */
130			if (IPPROTO_IP == protocol) {
131				protocol = answer->protocol;
132				break;
133			}
134			if (IPPROTO_IP == answer->protocol)
135				break;
136		}
137		err = -EPROTONOSUPPORT;
138	}
139
140	if (err) {
141		if (try_loading_module < 2) {
142			rcu_read_unlock();
143			/*
144			 * Be more specific, e.g. net-pf-10-proto-132-type-1
145			 * (net-pf-PF_INET6-proto-IPPROTO_SCTP-type-SOCK_STREAM)
146			 */
147			if (++try_loading_module == 1)
148				request_module("net-pf-%d-proto-%d-type-%d",
149						PF_INET6, protocol, sock->type);
150			/*
151			 * Fall back to generic, e.g. net-pf-10-proto-132
152			 * (net-pf-PF_INET6-proto-IPPROTO_SCTP)
153			 */
154			else
155				request_module("net-pf-%d-proto-%d",
156						PF_INET6, protocol);
157			goto lookup_protocol;
158		} else
159			goto out_rcu_unlock;
160	}
161
162	err = -EPERM;
163	if (sock->type == SOCK_RAW && !kern && !capable(CAP_NET_RAW))
164		goto out_rcu_unlock;
165
166	sock->ops = answer->ops;
167	answer_prot = answer->prot;
168	answer_no_check = answer->no_check;
169	answer_flags = answer->flags;
170	rcu_read_unlock();
171
172	WARN_ON(answer_prot->slab == NULL);
173
174	err = -ENOBUFS;
175	sk = sk_alloc(net, PF_INET6, GFP_KERNEL, answer_prot);
176	if (sk == NULL)
177		goto out;
178
179	sock_init_data(sock, sk);
180
181	err = 0;
182	sk->sk_no_check = answer_no_check;
183	if (INET_PROTOSW_REUSE & answer_flags)
184		sk->sk_reuse = 1;
185
186	inet = inet_sk(sk);
187	inet->is_icsk = (INET_PROTOSW_ICSK & answer_flags) != 0;
188
189	if (SOCK_RAW == sock->type) {
190		inet->inet_num = protocol;
191		if (IPPROTO_RAW == protocol)
192			inet->hdrincl = 1;
193	}
194
195	sk->sk_destruct		= inet_sock_destruct;
196	sk->sk_family		= PF_INET6;
197	sk->sk_protocol		= protocol;
198
199	sk->sk_backlog_rcv	= answer->prot->backlog_rcv;
200
201	inet_sk(sk)->pinet6 = np = inet6_sk_generic(sk);
202	np->hop_limit	= -1;
203	np->mcast_hops	= IPV6_DEFAULT_MCASTHOPS;
204	np->mc_loop	= 1;
205	np->pmtudisc	= IPV6_PMTUDISC_WANT;
206	np->ipv6only	= net->ipv6.sysctl.bindv6only;
207
208	/* Init the ipv4 part of the socket since we can have sockets
209	 * using v6 API for ipv4.
210	 */
211	inet->uc_ttl	= -1;
212
213	inet->mc_loop	= 1;
214	inet->mc_ttl	= 1;
215	inet->mc_index	= 0;
216	inet->mc_list	= NULL;
217
218	if (ipv4_config.no_pmtu_disc)
219		inet->pmtudisc = IP_PMTUDISC_DONT;
220	else
221		inet->pmtudisc = IP_PMTUDISC_WANT;
222	/*
223	 * Increment only the relevant sk_prot->socks debug field, this changes
224	 * the previous behaviour of incrementing both the equivalent to
225	 * answer->prot->socks (inet6_sock_nr) and inet_sock_nr.
226	 *
227	 * This allows better debug granularity as we'll know exactly how many
228	 * UDPv6, TCPv6, etc socks were allocated, not the sum of all IPv6
229	 * transport protocol socks. -acme
230	 */
231	sk_refcnt_debug_inc(sk);
232
233	if (inet->inet_num) {
234		/* It assumes that any protocol which allows
235		 * the user to assign a number at socket
236		 * creation time automatically shares.
237		 */
238		inet->inet_sport = htons(inet->inet_num);
239		sk->sk_prot->hash(sk);
240	}
241	if (sk->sk_prot->init) {
242		err = sk->sk_prot->init(sk);
243		if (err) {
244			sk_common_release(sk);
245			goto out;
246		}
247	}
248out:
249	return err;
250out_rcu_unlock:
251	rcu_read_unlock();
252	goto out;
253}
254
255
256/* bind for INET6 API */
257int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
258{
259	struct sockaddr_in6 *addr=(struct sockaddr_in6 *)uaddr;
260	struct sock *sk = sock->sk;
261	struct inet_sock *inet = inet_sk(sk);
262	struct ipv6_pinfo *np = inet6_sk(sk);
263	struct net *net = sock_net(sk);
264	__be32 v4addr = 0;
265	unsigned short snum;
266	int addr_type = 0;
267	int err = 0;
268
269	/* If the socket has its own bind function then use it. */
270	if (sk->sk_prot->bind)
271		return sk->sk_prot->bind(sk, uaddr, addr_len);
272
273	if (addr_len < SIN6_LEN_RFC2133)
274		return -EINVAL;
275
276	if (addr->sin6_family != AF_INET6)
277		return -EAFNOSUPPORT;
278
279	addr_type = ipv6_addr_type(&addr->sin6_addr);
280	if ((addr_type & IPV6_ADDR_MULTICAST) && sock->type == SOCK_STREAM)
281		return -EINVAL;
282
283	snum = ntohs(addr->sin6_port);
284	if (snum && snum < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE))
285		return -EACCES;
286
287	lock_sock(sk);
288
289	/* Check these errors (active socket, double bind). */
290	if (sk->sk_state != TCP_CLOSE || inet->inet_num) {
291		err = -EINVAL;
292		goto out;
293	}
294
295	/* Check if the address belongs to the host. */
296	if (addr_type == IPV6_ADDR_MAPPED) {
297		int chk_addr_ret;
298
299		/* Binding to v4-mapped address on a v6-only socket
300		 * makes no sense
301		 */
302		if (np->ipv6only) {
303			err = -EINVAL;
304			goto out;
305		}
306
307		/* Reproduce AF_INET checks to make the bindings consistent */
308		v4addr = addr->sin6_addr.s6_addr32[3];
309		chk_addr_ret = inet_addr_type(net, v4addr);
310		if (!sysctl_ip_nonlocal_bind &&
311		    !(inet->freebind || inet->transparent) &&
312		    v4addr != htonl(INADDR_ANY) &&
313		    chk_addr_ret != RTN_LOCAL &&
314		    chk_addr_ret != RTN_MULTICAST &&
315		    chk_addr_ret != RTN_BROADCAST) {
316			err = -EADDRNOTAVAIL;
317			goto out;
318		}
319	} else {
320		if (addr_type != IPV6_ADDR_ANY) {
321			struct net_device *dev = NULL;
322
323			rcu_read_lock();
324			if (addr_type & IPV6_ADDR_LINKLOCAL) {
325				if (addr_len >= sizeof(struct sockaddr_in6) &&
326				    addr->sin6_scope_id) {
327					/* Override any existing binding, if another one
328					 * is supplied by user.
329					 */
330					sk->sk_bound_dev_if = addr->sin6_scope_id;
331				}
332
333				/* Binding to link-local address requires an interface */
334				if (!sk->sk_bound_dev_if) {
335					err = -EINVAL;
336					goto out_unlock;
337				}
338				dev = dev_get_by_index_rcu(net, sk->sk_bound_dev_if);
339				if (!dev) {
340					err = -ENODEV;
341					goto out_unlock;
342				}
343			}
344
345			/* ipv4 addr of the socket is invalid.  Only the
346			 * unspecified and mapped address have a v4 equivalent.
347			 */
348			v4addr = LOOPBACK4_IPV6;
349			if (!(addr_type & IPV6_ADDR_MULTICAST))	{
350				if (!inet->transparent &&
351				    !ipv6_chk_addr(net, &addr->sin6_addr,
352						   dev, 0)) {
353					err = -EADDRNOTAVAIL;
354					goto out_unlock;
355				}
356			}
357			rcu_read_unlock();
358		}
359	}
360
361	inet->inet_rcv_saddr = v4addr;
362	inet->inet_saddr = v4addr;
363
364	ipv6_addr_copy(&np->rcv_saddr, &addr->sin6_addr);
365
366	if (!(addr_type & IPV6_ADDR_MULTICAST))
367		ipv6_addr_copy(&np->saddr, &addr->sin6_addr);
368
369	/* Make sure we are allowed to bind here. */
370	if (sk->sk_prot->get_port(sk, snum)) {
371		inet_reset_saddr(sk);
372		err = -EADDRINUSE;
373		goto out;
374	}
375
376	if (addr_type != IPV6_ADDR_ANY) {
377		sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
378		if (addr_type != IPV6_ADDR_MAPPED)
379			np->ipv6only = 1;
380	}
381	if (snum)
382		sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
383	inet->inet_sport = htons(inet->inet_num);
384	inet->inet_dport = 0;
385	inet->inet_daddr = 0;
386out:
387	release_sock(sk);
388	return err;
389out_unlock:
390	rcu_read_unlock();
391	goto out;
392}
393
394EXPORT_SYMBOL(inet6_bind);
395
396int inet6_release(struct socket *sock)
397{
398	struct sock *sk = sock->sk;
399
400	if (sk == NULL)
401		return -EINVAL;
402
403	/* Free mc lists */
404	ipv6_sock_mc_close(sk);
405
406	/* Free ac lists */
407	ipv6_sock_ac_close(sk);
408
409	return inet_release(sock);
410}
411
412EXPORT_SYMBOL(inet6_release);
413
414void inet6_destroy_sock(struct sock *sk)
415{
416	struct ipv6_pinfo *np = inet6_sk(sk);
417	struct sk_buff *skb;
418	struct ipv6_txoptions *opt;
419
420	/* Release rx options */
421
422	if ((skb = xchg(&np->pktoptions, NULL)) != NULL)
423		kfree_skb(skb);
424
425	if ((skb = xchg(&np->rxpmtu, NULL)) != NULL)
426		kfree_skb(skb);
427
428	/* Free flowlabels */
429	fl6_free_socklist(sk);
430
431	/* Free tx options */
432
433	if ((opt = xchg(&np->opt, NULL)) != NULL)
434		sock_kfree_s(sk, opt, opt->tot_len);
435}
436
437EXPORT_SYMBOL_GPL(inet6_destroy_sock);
438
439/*
440 *	This does both peername and sockname.
441 */
442
443int inet6_getname(struct socket *sock, struct sockaddr *uaddr,
444		 int *uaddr_len, int peer)
445{
446	struct sockaddr_in6 *sin=(struct sockaddr_in6 *)uaddr;
447	struct sock *sk = sock->sk;
448	struct inet_sock *inet = inet_sk(sk);
449	struct ipv6_pinfo *np = inet6_sk(sk);
450
451	sin->sin6_family = AF_INET6;
452	sin->sin6_flowinfo = 0;
453	sin->sin6_scope_id = 0;
454	if (peer) {
455		if (!inet->inet_dport)
456			return -ENOTCONN;
457		if (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
458		    peer == 1)
459			return -ENOTCONN;
460		sin->sin6_port = inet->inet_dport;
461		ipv6_addr_copy(&sin->sin6_addr, &np->daddr);
462		if (np->sndflow)
463			sin->sin6_flowinfo = np->flow_label;
464	} else {
465		if (ipv6_addr_any(&np->rcv_saddr))
466			ipv6_addr_copy(&sin->sin6_addr, &np->saddr);
467		else
468			ipv6_addr_copy(&sin->sin6_addr, &np->rcv_saddr);
469
470		sin->sin6_port = inet->inet_sport;
471	}
472	if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
473		sin->sin6_scope_id = sk->sk_bound_dev_if;
474	*uaddr_len = sizeof(*sin);
475	return 0;
476}
477
478EXPORT_SYMBOL(inet6_getname);
479
480int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
481{
482	struct sock *sk = sock->sk;
483	struct net *net = sock_net(sk);
484
485	switch(cmd)
486	{
487	case SIOCGSTAMP:
488		return sock_get_timestamp(sk, (struct timeval __user *)arg);
489
490	case SIOCGSTAMPNS:
491		return sock_get_timestampns(sk, (struct timespec __user *)arg);
492
493	case SIOCADDRT:
494	case SIOCDELRT:
495
496		return ipv6_route_ioctl(net, cmd, (void __user *)arg);
497
498	case SIOCSIFADDR:
499		return addrconf_add_ifaddr(net, (void __user *) arg);
500	case SIOCDIFADDR:
501		return addrconf_del_ifaddr(net, (void __user *) arg);
502	case SIOCSIFDSTADDR:
503		return addrconf_set_dstaddr(net, (void __user *) arg);
504	default:
505		if (!sk->sk_prot->ioctl)
506			return -ENOIOCTLCMD;
507		return sk->sk_prot->ioctl(sk, cmd, arg);
508	}
509	/*NOTREACHED*/
510	return 0;
511}
512
513EXPORT_SYMBOL(inet6_ioctl);
514
515const struct proto_ops inet6_stream_ops = {
516	.family		   = PF_INET6,
517	.owner		   = THIS_MODULE,
518	.release	   = inet6_release,
519	.bind		   = inet6_bind,
520	.connect	   = inet_stream_connect,	/* ok		*/
521	.socketpair	   = sock_no_socketpair,	/* a do nothing	*/
522	.accept		   = inet_accept,		/* ok		*/
523	.getname	   = inet6_getname,
524	.poll		   = tcp_poll,			/* ok		*/
525	.ioctl		   = inet6_ioctl,		/* must change  */
526	.listen		   = inet_listen,		/* ok		*/
527	.shutdown	   = inet_shutdown,		/* ok		*/
528	.setsockopt	   = sock_common_setsockopt,	/* ok		*/
529	.getsockopt	   = sock_common_getsockopt,	/* ok		*/
530	.sendmsg	   = inet_sendmsg,		/* ok		*/
531	.recvmsg	   = inet_recvmsg,		/* ok		*/
532	.mmap		   = sock_no_mmap,
533	.sendpage	   = inet_sendpage,
534	.splice_read	   = tcp_splice_read,
535#ifdef CONFIG_COMPAT
536	.compat_setsockopt = compat_sock_common_setsockopt,
537	.compat_getsockopt = compat_sock_common_getsockopt,
538#endif
539};
540
541const struct proto_ops inet6_dgram_ops = {
542	.family		   = PF_INET6,
543	.owner		   = THIS_MODULE,
544	.release	   = inet6_release,
545	.bind		   = inet6_bind,
546	.connect	   = inet_dgram_connect,	/* ok		*/
547	.socketpair	   = sock_no_socketpair,	/* a do nothing	*/
548	.accept		   = sock_no_accept,		/* a do nothing	*/
549	.getname	   = inet6_getname,
550	.poll		   = udp_poll,			/* ok		*/
551	.ioctl		   = inet6_ioctl,		/* must change  */
552	.listen		   = sock_no_listen,		/* ok		*/
553	.shutdown	   = inet_shutdown,		/* ok		*/
554	.setsockopt	   = sock_common_setsockopt,	/* ok		*/
555	.getsockopt	   = sock_common_getsockopt,	/* ok		*/
556	.sendmsg	   = inet_sendmsg,		/* ok		*/
557	.recvmsg	   = inet_recvmsg,		/* ok		*/
558	.mmap		   = sock_no_mmap,
559	.sendpage	   = sock_no_sendpage,
560#ifdef CONFIG_COMPAT
561	.compat_setsockopt = compat_sock_common_setsockopt,
562	.compat_getsockopt = compat_sock_common_getsockopt,
563#endif
564};
565
566static const struct net_proto_family inet6_family_ops = {
567	.family = PF_INET6,
568	.create = inet6_create,
569	.owner	= THIS_MODULE,
570};
571
572int inet6_register_protosw(struct inet_protosw *p)
573{
574	struct list_head *lh;
575	struct inet_protosw *answer;
576	struct list_head *last_perm;
577	int protocol = p->protocol;
578	int ret;
579
580	spin_lock_bh(&inetsw6_lock);
581
582	ret = -EINVAL;
583	if (p->type >= SOCK_MAX)
584		goto out_illegal;
585
586	/* If we are trying to override a permanent protocol, bail. */
587	answer = NULL;
588	ret = -EPERM;
589	last_perm = &inetsw6[p->type];
590	list_for_each(lh, &inetsw6[p->type]) {
591		answer = list_entry(lh, struct inet_protosw, list);
592
593		/* Check only the non-wild match. */
594		if (INET_PROTOSW_PERMANENT & answer->flags) {
595			if (protocol == answer->protocol)
596				break;
597			last_perm = lh;
598		}
599
600		answer = NULL;
601	}
602	if (answer)
603		goto out_permanent;
604
605	/* Add the new entry after the last permanent entry if any, so that
606	 * the new entry does not override a permanent entry when matched with
607	 * a wild-card protocol. But it is allowed to override any existing
608	 * non-permanent entry.  This means that when we remove this entry, the
609	 * system automatically returns to the old behavior.
610	 */
611	list_add_rcu(&p->list, last_perm);
612	ret = 0;
613out:
614	spin_unlock_bh(&inetsw6_lock);
615	return ret;
616
617out_permanent:
618	printk(KERN_ERR "Attempt to override permanent protocol %d.\n",
619	       protocol);
620	goto out;
621
622out_illegal:
623	printk(KERN_ERR
624	       "Ignoring attempt to register invalid socket type %d.\n",
625	       p->type);
626	goto out;
627}
628
629EXPORT_SYMBOL(inet6_register_protosw);
630
631void
632inet6_unregister_protosw(struct inet_protosw *p)
633{
634	if (INET_PROTOSW_PERMANENT & p->flags) {
635		printk(KERN_ERR
636		       "Attempt to unregister permanent protocol %d.\n",
637		       p->protocol);
638	} else {
639		spin_lock_bh(&inetsw6_lock);
640		list_del_rcu(&p->list);
641		spin_unlock_bh(&inetsw6_lock);
642
643		synchronize_net();
644	}
645}
646
647EXPORT_SYMBOL(inet6_unregister_protosw);
648
649int inet6_sk_rebuild_header(struct sock *sk)
650{
651	struct ipv6_pinfo *np = inet6_sk(sk);
652	struct dst_entry *dst;
653
654	dst = __sk_dst_check(sk, np->dst_cookie);
655
656	if (dst == NULL) {
657		struct inet_sock *inet = inet_sk(sk);
658		struct in6_addr *final_p, final;
659		struct flowi6 fl6;
660
661		memset(&fl6, 0, sizeof(fl6));
662		fl6.flowi6_proto = sk->sk_protocol;
663		ipv6_addr_copy(&fl6.daddr, &np->daddr);
664		ipv6_addr_copy(&fl6.saddr, &np->saddr);
665		fl6.flowlabel = np->flow_label;
666		fl6.flowi6_oif = sk->sk_bound_dev_if;
667		fl6.flowi6_mark = sk->sk_mark;
668		fl6.fl6_dport = inet->inet_dport;
669		fl6.fl6_sport = inet->inet_sport;
670		security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
671
672		final_p = fl6_update_dst(&fl6, np->opt, &final);
673
674		dst = ip6_dst_lookup_flow(sk, &fl6, final_p, false);
675		if (IS_ERR(dst)) {
676			sk->sk_route_caps = 0;
677			sk->sk_err_soft = -PTR_ERR(dst);
678			return PTR_ERR(dst);
679		}
680
681		__ip6_dst_store(sk, dst, NULL, NULL);
682	}
683
684	return 0;
685}
686
687EXPORT_SYMBOL_GPL(inet6_sk_rebuild_header);
688
689int ipv6_opt_accepted(struct sock *sk, struct sk_buff *skb)
690{
691	struct ipv6_pinfo *np = inet6_sk(sk);
692	struct inet6_skb_parm *opt = IP6CB(skb);
693
694	if (np->rxopt.all) {
695		if ((opt->hop && (np->rxopt.bits.hopopts ||
696				  np->rxopt.bits.ohopopts)) ||
697		    ((IPV6_FLOWINFO_MASK &
698		      *(__be32 *)skb_network_header(skb)) &&
699		     np->rxopt.bits.rxflow) ||
700		    (opt->srcrt && (np->rxopt.bits.srcrt ||
701		     np->rxopt.bits.osrcrt)) ||
702		    ((opt->dst1 || opt->dst0) &&
703		     (np->rxopt.bits.dstopts || np->rxopt.bits.odstopts)))
704			return 1;
705	}
706	return 0;
707}
708
709EXPORT_SYMBOL_GPL(ipv6_opt_accepted);
710
711static int ipv6_gso_pull_exthdrs(struct sk_buff *skb, int proto)
712{
713	const struct inet6_protocol *ops = NULL;
714
715	for (;;) {
716		struct ipv6_opt_hdr *opth;
717		int len;
718
719		if (proto != NEXTHDR_HOP) {
720			ops = rcu_dereference(inet6_protos[proto]);
721
722			if (unlikely(!ops))
723				break;
724
725			if (!(ops->flags & INET6_PROTO_GSO_EXTHDR))
726				break;
727		}
728
729		if (unlikely(!pskb_may_pull(skb, 8)))
730			break;
731
732		opth = (void *)skb->data;
733		len = ipv6_optlen(opth);
734
735		if (unlikely(!pskb_may_pull(skb, len)))
736			break;
737
738		proto = opth->nexthdr;
739		__skb_pull(skb, len);
740	}
741
742	return proto;
743}
744
745static int ipv6_gso_send_check(struct sk_buff *skb)
746{
747	const struct ipv6hdr *ipv6h;
748	const struct inet6_protocol *ops;
749	int err = -EINVAL;
750
751	if (unlikely(!pskb_may_pull(skb, sizeof(*ipv6h))))
752		goto out;
753
754	ipv6h = ipv6_hdr(skb);
755	__skb_pull(skb, sizeof(*ipv6h));
756	err = -EPROTONOSUPPORT;
757
758	rcu_read_lock();
759	ops = rcu_dereference(inet6_protos[
760		ipv6_gso_pull_exthdrs(skb, ipv6h->nexthdr)]);
761
762	if (likely(ops && ops->gso_send_check)) {
763		skb_reset_transport_header(skb);
764		err = ops->gso_send_check(skb);
765	}
766	rcu_read_unlock();
767
768out:
769	return err;
770}
771
772static struct sk_buff *ipv6_gso_segment(struct sk_buff *skb, u32 features)
773{
774	struct sk_buff *segs = ERR_PTR(-EINVAL);
775	struct ipv6hdr *ipv6h;
776	const struct inet6_protocol *ops;
777	int proto;
778	struct frag_hdr *fptr;
779	unsigned int unfrag_ip6hlen;
780	u8 *prevhdr;
781	int offset = 0;
782
783	if (!(features & NETIF_F_V6_CSUM))
784		features &= ~NETIF_F_SG;
785
786	if (unlikely(skb_shinfo(skb)->gso_type &
787		     ~(SKB_GSO_UDP |
788		       SKB_GSO_DODGY |
789		       SKB_GSO_TCP_ECN |
790		       SKB_GSO_TCPV6 |
791		       0)))
792		goto out;
793
794	if (unlikely(!pskb_may_pull(skb, sizeof(*ipv6h))))
795		goto out;
796
797	ipv6h = ipv6_hdr(skb);
798	__skb_pull(skb, sizeof(*ipv6h));
799	segs = ERR_PTR(-EPROTONOSUPPORT);
800
801	proto = ipv6_gso_pull_exthdrs(skb, ipv6h->nexthdr);
802	rcu_read_lock();
803	ops = rcu_dereference(inet6_protos[proto]);
804	if (likely(ops && ops->gso_segment)) {
805		skb_reset_transport_header(skb);
806		segs = ops->gso_segment(skb, features);
807	}
808	rcu_read_unlock();
809
810	if (IS_ERR(segs))
811		goto out;
812
813	for (skb = segs; skb; skb = skb->next) {
814		ipv6h = ipv6_hdr(skb);
815		ipv6h->payload_len = htons(skb->len - skb->mac_len -
816					   sizeof(*ipv6h));
817		if (proto == IPPROTO_UDP) {
818			unfrag_ip6hlen = ip6_find_1stfragopt(skb, &prevhdr);
819			fptr = (struct frag_hdr *)(skb_network_header(skb) +
820				unfrag_ip6hlen);
821			fptr->frag_off = htons(offset);
822			if (skb->next != NULL)
823				fptr->frag_off |= htons(IP6_MF);
824			offset += (ntohs(ipv6h->payload_len) -
825				   sizeof(struct frag_hdr));
826		}
827	}
828
829out:
830	return segs;
831}
832
833struct ipv6_gro_cb {
834	struct napi_gro_cb napi;
835	int proto;
836};
837
838#define IPV6_GRO_CB(skb) ((struct ipv6_gro_cb *)(skb)->cb)
839
840static struct sk_buff **ipv6_gro_receive(struct sk_buff **head,
841					 struct sk_buff *skb)
842{
843	const struct inet6_protocol *ops;
844	struct sk_buff **pp = NULL;
845	struct sk_buff *p;
846	struct ipv6hdr *iph;
847	unsigned int nlen;
848	unsigned int hlen;
849	unsigned int off;
850	int flush = 1;
851	int proto;
852	__wsum csum;
853
854	off = skb_gro_offset(skb);
855	hlen = off + sizeof(*iph);
856	iph = skb_gro_header_fast(skb, off);
857	if (skb_gro_header_hard(skb, hlen)) {
858		iph = skb_gro_header_slow(skb, hlen, off);
859		if (unlikely(!iph))
860			goto out;
861	}
862
863	skb_gro_pull(skb, sizeof(*iph));
864	skb_set_transport_header(skb, skb_gro_offset(skb));
865
866	flush += ntohs(iph->payload_len) != skb_gro_len(skb);
867
868	rcu_read_lock();
869	proto = iph->nexthdr;
870	ops = rcu_dereference(inet6_protos[proto]);
871	if (!ops || !ops->gro_receive) {
872		__pskb_pull(skb, skb_gro_offset(skb));
873		proto = ipv6_gso_pull_exthdrs(skb, proto);
874		skb_gro_pull(skb, -skb_transport_offset(skb));
875		skb_reset_transport_header(skb);
876		__skb_push(skb, skb_gro_offset(skb));
877
878		if (!ops || !ops->gro_receive)
879			goto out_unlock;
880
881		iph = ipv6_hdr(skb);
882	}
883
884	IPV6_GRO_CB(skb)->proto = proto;
885
886	flush--;
887	nlen = skb_network_header_len(skb);
888
889	for (p = *head; p; p = p->next) {
890		struct ipv6hdr *iph2;
891
892		if (!NAPI_GRO_CB(p)->same_flow)
893			continue;
894
895		iph2 = ipv6_hdr(p);
896
897		/* All fields must match except length. */
898		if (nlen != skb_network_header_len(p) ||
899		    memcmp(iph, iph2, offsetof(struct ipv6hdr, payload_len)) ||
900		    memcmp(&iph->nexthdr, &iph2->nexthdr,
901			   nlen - offsetof(struct ipv6hdr, nexthdr))) {
902			NAPI_GRO_CB(p)->same_flow = 0;
903			continue;
904		}
905
906		NAPI_GRO_CB(p)->flush |= flush;
907	}
908
909	NAPI_GRO_CB(skb)->flush |= flush;
910
911	csum = skb->csum;
912	skb_postpull_rcsum(skb, iph, skb_network_header_len(skb));
913
914	pp = ops->gro_receive(head, skb);
915
916	skb->csum = csum;
917
918out_unlock:
919	rcu_read_unlock();
920
921out:
922	NAPI_GRO_CB(skb)->flush |= flush;
923
924	return pp;
925}
926
927static int ipv6_gro_complete(struct sk_buff *skb)
928{
929	const struct inet6_protocol *ops;
930	struct ipv6hdr *iph = ipv6_hdr(skb);
931	int err = -ENOSYS;
932
933	iph->payload_len = htons(skb->len - skb_network_offset(skb) -
934				 sizeof(*iph));
935
936	rcu_read_lock();
937	ops = rcu_dereference(inet6_protos[IPV6_GRO_CB(skb)->proto]);
938	if (WARN_ON(!ops || !ops->gro_complete))
939		goto out_unlock;
940
941	err = ops->gro_complete(skb);
942
943out_unlock:
944	rcu_read_unlock();
945
946	return err;
947}
948
949static struct packet_type ipv6_packet_type __read_mostly = {
950	.type = cpu_to_be16(ETH_P_IPV6),
951	.func = ipv6_rcv,
952	.gso_send_check = ipv6_gso_send_check,
953	.gso_segment = ipv6_gso_segment,
954	.gro_receive = ipv6_gro_receive,
955	.gro_complete = ipv6_gro_complete,
956};
957
958static int __init ipv6_packet_init(void)
959{
960	dev_add_pack(&ipv6_packet_type);
961	return 0;
962}
963
964static void ipv6_packet_cleanup(void)
965{
966	dev_remove_pack(&ipv6_packet_type);
967}
968
969static int __net_init ipv6_init_mibs(struct net *net)
970{
971	if (snmp_mib_init((void __percpu **)net->mib.udp_stats_in6,
972			  sizeof(struct udp_mib),
973			  __alignof__(struct udp_mib)) < 0)
974		return -ENOMEM;
975	if (snmp_mib_init((void __percpu **)net->mib.udplite_stats_in6,
976			  sizeof(struct udp_mib),
977			  __alignof__(struct udp_mib)) < 0)
978		goto err_udplite_mib;
979	if (snmp_mib_init((void __percpu **)net->mib.ipv6_statistics,
980			  sizeof(struct ipstats_mib),
981			  __alignof__(struct ipstats_mib)) < 0)
982		goto err_ip_mib;
983	if (snmp_mib_init((void __percpu **)net->mib.icmpv6_statistics,
984			  sizeof(struct icmpv6_mib),
985			  __alignof__(struct icmpv6_mib)) < 0)
986		goto err_icmp_mib;
987	if (snmp_mib_init((void __percpu **)net->mib.icmpv6msg_statistics,
988			  sizeof(struct icmpv6msg_mib),
989			  __alignof__(struct icmpv6msg_mib)) < 0)
990		goto err_icmpmsg_mib;
991	return 0;
992
993err_icmpmsg_mib:
994	snmp_mib_free((void __percpu **)net->mib.icmpv6_statistics);
995err_icmp_mib:
996	snmp_mib_free((void __percpu **)net->mib.ipv6_statistics);
997err_ip_mib:
998	snmp_mib_free((void __percpu **)net->mib.udplite_stats_in6);
999err_udplite_mib:
1000	snmp_mib_free((void __percpu **)net->mib.udp_stats_in6);
1001	return -ENOMEM;
1002}
1003
1004static void ipv6_cleanup_mibs(struct net *net)
1005{
1006	snmp_mib_free((void __percpu **)net->mib.udp_stats_in6);
1007	snmp_mib_free((void __percpu **)net->mib.udplite_stats_in6);
1008	snmp_mib_free((void __percpu **)net->mib.ipv6_statistics);
1009	snmp_mib_free((void __percpu **)net->mib.icmpv6_statistics);
1010	snmp_mib_free((void __percpu **)net->mib.icmpv6msg_statistics);
1011}
1012
1013static int __net_init inet6_net_init(struct net *net)
1014{
1015	int err = 0;
1016
1017	net->ipv6.sysctl.bindv6only = 0;
1018	net->ipv6.sysctl.icmpv6_time = 1*HZ;
1019
1020	err = ipv6_init_mibs(net);
1021	if (err)
1022		return err;
1023#ifdef CONFIG_PROC_FS
1024	err = udp6_proc_init(net);
1025	if (err)
1026		goto out;
1027	err = tcp6_proc_init(net);
1028	if (err)
1029		goto proc_tcp6_fail;
1030	err = ac6_proc_init(net);
1031	if (err)
1032		goto proc_ac6_fail;
1033#endif
1034	return err;
1035
1036#ifdef CONFIG_PROC_FS
1037proc_ac6_fail:
1038	tcp6_proc_exit(net);
1039proc_tcp6_fail:
1040	udp6_proc_exit(net);
1041out:
1042	ipv6_cleanup_mibs(net);
1043	return err;
1044#endif
1045}
1046
1047static void __net_exit inet6_net_exit(struct net *net)
1048{
1049#ifdef CONFIG_PROC_FS
1050	udp6_proc_exit(net);
1051	tcp6_proc_exit(net);
1052	ac6_proc_exit(net);
1053#endif
1054	ipv6_cleanup_mibs(net);
1055}
1056
1057static struct pernet_operations inet6_net_ops = {
1058	.init = inet6_net_init,
1059	.exit = inet6_net_exit,
1060};
1061
1062static int __init inet6_init(void)
1063{
1064	struct sk_buff *dummy_skb;
1065	struct list_head *r;
1066	int err = 0;
1067
1068	BUILD_BUG_ON(sizeof(struct inet6_skb_parm) > sizeof(dummy_skb->cb));
1069
1070	/* Register the socket-side information for inet6_create.  */
1071	for(r = &inetsw6[0]; r < &inetsw6[SOCK_MAX]; ++r)
1072		INIT_LIST_HEAD(r);
1073
1074	if (disable_ipv6_mod) {
1075		printk(KERN_INFO
1076		       "IPv6: Loaded, but administratively disabled, "
1077		       "reboot required to enable\n");
1078		goto out;
1079	}
1080
1081	err = proto_register(&tcpv6_prot, 1);
1082	if (err)
1083		goto out;
1084
1085	err = proto_register(&udpv6_prot, 1);
1086	if (err)
1087		goto out_unregister_tcp_proto;
1088
1089	err = proto_register(&udplitev6_prot, 1);
1090	if (err)
1091		goto out_unregister_udp_proto;
1092
1093	err = proto_register(&rawv6_prot, 1);
1094	if (err)
1095		goto out_unregister_udplite_proto;
1096
1097
1098	/* We MUST register RAW sockets before we create the ICMP6,
1099	 * IGMP6, or NDISC control sockets.
1100	 */
1101	err = rawv6_init();
1102	if (err)
1103		goto out_unregister_raw_proto;
1104
1105	/* Register the family here so that the init calls below will
1106	 * be able to create sockets. (?? is this dangerous ??)
1107	 */
1108	err = sock_register(&inet6_family_ops);
1109	if (err)
1110		goto out_sock_register_fail;
1111
1112#ifdef CONFIG_SYSCTL
1113	err = ipv6_static_sysctl_register();
1114	if (err)
1115		goto static_sysctl_fail;
1116#endif
1117	/*
1118	 *	ipngwg API draft makes clear that the correct semantics
1119	 *	for TCP and UDP is to consider one TCP and UDP instance
1120	 *	in a host available by both INET and INET6 APIs and
1121	 *	able to communicate via both network protocols.
1122	 */
1123
1124	err = register_pernet_subsys(&inet6_net_ops);
1125	if (err)
1126		goto register_pernet_fail;
1127	err = icmpv6_init();
1128	if (err)
1129		goto icmp_fail;
1130	err = ip6_mr_init();
1131	if (err)
1132		goto ipmr_fail;
1133	err = ndisc_init();
1134	if (err)
1135		goto ndisc_fail;
1136	err = igmp6_init();
1137	if (err)
1138		goto igmp_fail;
1139	err = ipv6_netfilter_init();
1140	if (err)
1141		goto netfilter_fail;
1142	/* Create /proc/foo6 entries. */
1143#ifdef CONFIG_PROC_FS
1144	err = -ENOMEM;
1145	if (raw6_proc_init())
1146		goto proc_raw6_fail;
1147	if (udplite6_proc_init())
1148		goto proc_udplite6_fail;
1149	if (ipv6_misc_proc_init())
1150		goto proc_misc6_fail;
1151	if (if6_proc_init())
1152		goto proc_if6_fail;
1153#endif
1154	err = ip6_route_init();
1155	if (err)
1156		goto ip6_route_fail;
1157	err = ip6_flowlabel_init();
1158	if (err)
1159		goto ip6_flowlabel_fail;
1160	err = addrconf_init();
1161	if (err)
1162		goto addrconf_fail;
1163
1164	/* Init v6 extension headers. */
1165	err = ipv6_exthdrs_init();
1166	if (err)
1167		goto ipv6_exthdrs_fail;
1168
1169	err = ipv6_frag_init();
1170	if (err)
1171		goto ipv6_frag_fail;
1172
1173	/* Init v6 transport protocols. */
1174	err = udpv6_init();
1175	if (err)
1176		goto udpv6_fail;
1177
1178	err = udplitev6_init();
1179	if (err)
1180		goto udplitev6_fail;
1181
1182	err = tcpv6_init();
1183	if (err)
1184		goto tcpv6_fail;
1185
1186	err = ipv6_packet_init();
1187	if (err)
1188		goto ipv6_packet_fail;
1189
1190#ifdef CONFIG_SYSCTL
1191	err = ipv6_sysctl_register();
1192	if (err)
1193		goto sysctl_fail;
1194#endif
1195out:
1196	return err;
1197
1198#ifdef CONFIG_SYSCTL
1199sysctl_fail:
1200	ipv6_packet_cleanup();
1201#endif
1202ipv6_packet_fail:
1203	tcpv6_exit();
1204tcpv6_fail:
1205	udplitev6_exit();
1206udplitev6_fail:
1207	udpv6_exit();
1208udpv6_fail:
1209	ipv6_frag_exit();
1210ipv6_frag_fail:
1211	ipv6_exthdrs_exit();
1212ipv6_exthdrs_fail:
1213	addrconf_cleanup();
1214addrconf_fail:
1215	ip6_flowlabel_cleanup();
1216ip6_flowlabel_fail:
1217	ip6_route_cleanup();
1218ip6_route_fail:
1219#ifdef CONFIG_PROC_FS
1220	if6_proc_exit();
1221proc_if6_fail:
1222	ipv6_misc_proc_exit();
1223proc_misc6_fail:
1224	udplite6_proc_exit();
1225proc_udplite6_fail:
1226	raw6_proc_exit();
1227proc_raw6_fail:
1228#endif
1229	ipv6_netfilter_fini();
1230netfilter_fail:
1231	igmp6_cleanup();
1232igmp_fail:
1233	ndisc_cleanup();
1234ndisc_fail:
1235	ip6_mr_cleanup();
1236ipmr_fail:
1237	icmpv6_cleanup();
1238icmp_fail:
1239	unregister_pernet_subsys(&inet6_net_ops);
1240register_pernet_fail:
1241#ifdef CONFIG_SYSCTL
1242	ipv6_static_sysctl_unregister();
1243static_sysctl_fail:
1244#endif
1245	sock_unregister(PF_INET6);
1246	rtnl_unregister_all(PF_INET6);
1247out_sock_register_fail:
1248	rawv6_exit();
1249out_unregister_raw_proto:
1250	proto_unregister(&rawv6_prot);
1251out_unregister_udplite_proto:
1252	proto_unregister(&udplitev6_prot);
1253out_unregister_udp_proto:
1254	proto_unregister(&udpv6_prot);
1255out_unregister_tcp_proto:
1256	proto_unregister(&tcpv6_prot);
1257	goto out;
1258}
1259module_init(inet6_init);
1260
1261static void __exit inet6_exit(void)
1262{
1263	if (disable_ipv6_mod)
1264		return;
1265
1266	/* First of all disallow new sockets creation. */
1267	sock_unregister(PF_INET6);
1268	/* Disallow any further netlink messages */
1269	rtnl_unregister_all(PF_INET6);
1270
1271#ifdef CONFIG_SYSCTL
1272	ipv6_sysctl_unregister();
1273#endif
1274	udpv6_exit();
1275	udplitev6_exit();
1276	tcpv6_exit();
1277
1278	/* Cleanup code parts. */
1279	ipv6_packet_cleanup();
1280	ipv6_frag_exit();
1281	ipv6_exthdrs_exit();
1282	addrconf_cleanup();
1283	ip6_flowlabel_cleanup();
1284	ip6_route_cleanup();
1285#ifdef CONFIG_PROC_FS
1286
1287	/* Cleanup code parts. */
1288	if6_proc_exit();
1289	ipv6_misc_proc_exit();
1290	udplite6_proc_exit();
1291	raw6_proc_exit();
1292#endif
1293	ipv6_netfilter_fini();
1294	igmp6_cleanup();
1295	ndisc_cleanup();
1296	ip6_mr_cleanup();
1297	icmpv6_cleanup();
1298	rawv6_exit();
1299
1300	unregister_pernet_subsys(&inet6_net_ops);
1301#ifdef CONFIG_SYSCTL
1302	ipv6_static_sysctl_unregister();
1303#endif
1304	proto_unregister(&rawv6_prot);
1305	proto_unregister(&udplitev6_prot);
1306	proto_unregister(&udpv6_prot);
1307	proto_unregister(&tcpv6_prot);
1308
1309	rcu_barrier(); /* Wait for completion of call_rcu()'s */
1310}
1311module_exit(inet6_exit);
1312
1313MODULE_ALIAS_NETPROTO(PF_INET6);
1314