Merge tag 'usb-4.20-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
[sfrench/cifs-2.6.git] / net / ipv6 / af_inet6.c
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 <linux/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->mc_all      = 1;
213         np->pmtudisc    = IPV6_PMTUDISC_WANT;
214         np->repflow     = net->ipv6.sysctl.flowlabel_reflect;
215         sk->sk_ipv6only = net->ipv6.sysctl.bindv6only;
216
217         /* Init the ipv4 part of the socket since we can have sockets
218          * using v6 API for ipv4.
219          */
220         inet->uc_ttl    = -1;
221
222         inet->mc_loop   = 1;
223         inet->mc_ttl    = 1;
224         inet->mc_index  = 0;
225         inet->mc_list   = NULL;
226         inet->rcv_tos   = 0;
227
228         if (net->ipv4.sysctl_ip_no_pmtu_disc)
229                 inet->pmtudisc = IP_PMTUDISC_DONT;
230         else
231                 inet->pmtudisc = IP_PMTUDISC_WANT;
232         /*
233          * Increment only the relevant sk_prot->socks debug field, this changes
234          * the previous behaviour of incrementing both the equivalent to
235          * answer->prot->socks (inet6_sock_nr) and inet_sock_nr.
236          *
237          * This allows better debug granularity as we'll know exactly how many
238          * UDPv6, TCPv6, etc socks were allocated, not the sum of all IPv6
239          * transport protocol socks. -acme
240          */
241         sk_refcnt_debug_inc(sk);
242
243         if (inet->inet_num) {
244                 /* It assumes that any protocol which allows
245                  * the user to assign a number at socket
246                  * creation time automatically shares.
247                  */
248                 inet->inet_sport = htons(inet->inet_num);
249                 err = sk->sk_prot->hash(sk);
250                 if (err) {
251                         sk_common_release(sk);
252                         goto out;
253                 }
254         }
255         if (sk->sk_prot->init) {
256                 err = sk->sk_prot->init(sk);
257                 if (err) {
258                         sk_common_release(sk);
259                         goto out;
260                 }
261         }
262
263         if (!kern) {
264                 err = BPF_CGROUP_RUN_PROG_INET_SOCK(sk);
265                 if (err) {
266                         sk_common_release(sk);
267                         goto out;
268                 }
269         }
270 out:
271         return err;
272 out_rcu_unlock:
273         rcu_read_unlock();
274         goto out;
275 }
276
277 static int __inet6_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len,
278                         bool force_bind_address_no_port, bool with_lock)
279 {
280         struct sockaddr_in6 *addr = (struct sockaddr_in6 *)uaddr;
281         struct inet_sock *inet = inet_sk(sk);
282         struct ipv6_pinfo *np = inet6_sk(sk);
283         struct net *net = sock_net(sk);
284         __be32 v4addr = 0;
285         unsigned short snum;
286         bool saved_ipv6only;
287         int addr_type = 0;
288         int err = 0;
289
290         if (addr->sin6_family != AF_INET6)
291                 return -EAFNOSUPPORT;
292
293         addr_type = ipv6_addr_type(&addr->sin6_addr);
294         if ((addr_type & IPV6_ADDR_MULTICAST) && sk->sk_type == SOCK_STREAM)
295                 return -EINVAL;
296
297         snum = ntohs(addr->sin6_port);
298         if (snum && snum < inet_prot_sock(net) &&
299             !ns_capable(net->user_ns, CAP_NET_BIND_SERVICE))
300                 return -EACCES;
301
302         if (with_lock)
303                 lock_sock(sk);
304
305         /* Check these errors (active socket, double bind). */
306         if (sk->sk_state != TCP_CLOSE || inet->inet_num) {
307                 err = -EINVAL;
308                 goto out;
309         }
310
311         /* Check if the address belongs to the host. */
312         if (addr_type == IPV6_ADDR_MAPPED) {
313                 int chk_addr_ret;
314
315                 /* Binding to v4-mapped address on a v6-only socket
316                  * makes no sense
317                  */
318                 if (sk->sk_ipv6only) {
319                         err = -EINVAL;
320                         goto out;
321                 }
322
323                 /* Reproduce AF_INET checks to make the bindings consistent */
324                 v4addr = addr->sin6_addr.s6_addr32[3];
325                 chk_addr_ret = inet_addr_type(net, v4addr);
326                 if (!inet_can_nonlocal_bind(net, inet) &&
327                     v4addr != htonl(INADDR_ANY) &&
328                     chk_addr_ret != RTN_LOCAL &&
329                     chk_addr_ret != RTN_MULTICAST &&
330                     chk_addr_ret != RTN_BROADCAST) {
331                         err = -EADDRNOTAVAIL;
332                         goto out;
333                 }
334         } else {
335                 if (addr_type != IPV6_ADDR_ANY) {
336                         struct net_device *dev = NULL;
337
338                         rcu_read_lock();
339                         if (__ipv6_addr_needs_scope_id(addr_type)) {
340                                 if (addr_len >= sizeof(struct sockaddr_in6) &&
341                                     addr->sin6_scope_id) {
342                                         /* Override any existing binding, if another one
343                                          * is supplied by user.
344                                          */
345                                         sk->sk_bound_dev_if = addr->sin6_scope_id;
346                                 }
347
348                                 /* Binding to link-local address requires an interface */
349                                 if (!sk->sk_bound_dev_if) {
350                                         err = -EINVAL;
351                                         goto out_unlock;
352                                 }
353                                 dev = dev_get_by_index_rcu(net, sk->sk_bound_dev_if);
354                                 if (!dev) {
355                                         err = -ENODEV;
356                                         goto out_unlock;
357                                 }
358                         }
359
360                         /* ipv4 addr of the socket is invalid.  Only the
361                          * unspecified and mapped address have a v4 equivalent.
362                          */
363                         v4addr = LOOPBACK4_IPV6;
364                         if (!(addr_type & IPV6_ADDR_MULTICAST)) {
365                                 if (!ipv6_can_nonlocal_bind(net, inet) &&
366                                     !ipv6_chk_addr(net, &addr->sin6_addr,
367                                                    dev, 0)) {
368                                         err = -EADDRNOTAVAIL;
369                                         goto out_unlock;
370                                 }
371                         }
372                         rcu_read_unlock();
373                 }
374         }
375
376         inet->inet_rcv_saddr = v4addr;
377         inet->inet_saddr = v4addr;
378
379         sk->sk_v6_rcv_saddr = addr->sin6_addr;
380
381         if (!(addr_type & IPV6_ADDR_MULTICAST))
382                 np->saddr = addr->sin6_addr;
383
384         saved_ipv6only = sk->sk_ipv6only;
385         if (addr_type != IPV6_ADDR_ANY && addr_type != IPV6_ADDR_MAPPED)
386                 sk->sk_ipv6only = 1;
387
388         /* Make sure we are allowed to bind here. */
389         if (snum || !(inet->bind_address_no_port ||
390                       force_bind_address_no_port)) {
391                 if (sk->sk_prot->get_port(sk, snum)) {
392                         sk->sk_ipv6only = saved_ipv6only;
393                         inet_reset_saddr(sk);
394                         err = -EADDRINUSE;
395                         goto out;
396                 }
397                 err = BPF_CGROUP_RUN_PROG_INET6_POST_BIND(sk);
398                 if (err) {
399                         sk->sk_ipv6only = saved_ipv6only;
400                         inet_reset_saddr(sk);
401                         goto out;
402                 }
403         }
404
405         if (addr_type != IPV6_ADDR_ANY)
406                 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
407         if (snum)
408                 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
409         inet->inet_sport = htons(inet->inet_num);
410         inet->inet_dport = 0;
411         inet->inet_daddr = 0;
412 out:
413         if (with_lock)
414                 release_sock(sk);
415         return err;
416 out_unlock:
417         rcu_read_unlock();
418         goto out;
419 }
420
421 /* bind for INET6 API */
422 int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
423 {
424         struct sock *sk = sock->sk;
425         int err = 0;
426
427         /* If the socket has its own bind function then use it. */
428         if (sk->sk_prot->bind)
429                 return sk->sk_prot->bind(sk, uaddr, addr_len);
430
431         if (addr_len < SIN6_LEN_RFC2133)
432                 return -EINVAL;
433
434         /* BPF prog is run before any checks are done so that if the prog
435          * changes context in a wrong way it will be caught.
436          */
437         err = BPF_CGROUP_RUN_PROG_INET6_BIND(sk, uaddr);
438         if (err)
439                 return err;
440
441         return __inet6_bind(sk, uaddr, addr_len, false, true);
442 }
443 EXPORT_SYMBOL(inet6_bind);
444
445 int inet6_release(struct socket *sock)
446 {
447         struct sock *sk = sock->sk;
448
449         if (!sk)
450                 return -EINVAL;
451
452         /* Free mc lists */
453         ipv6_sock_mc_close(sk);
454
455         /* Free ac lists */
456         ipv6_sock_ac_close(sk);
457
458         return inet_release(sock);
459 }
460 EXPORT_SYMBOL(inet6_release);
461
462 void inet6_destroy_sock(struct sock *sk)
463 {
464         struct ipv6_pinfo *np = inet6_sk(sk);
465         struct sk_buff *skb;
466         struct ipv6_txoptions *opt;
467
468         /* Release rx options */
469
470         skb = xchg(&np->pktoptions, NULL);
471         kfree_skb(skb);
472
473         skb = xchg(&np->rxpmtu, NULL);
474         kfree_skb(skb);
475
476         /* Free flowlabels */
477         fl6_free_socklist(sk);
478
479         /* Free tx options */
480
481         opt = xchg((__force struct ipv6_txoptions **)&np->opt, NULL);
482         if (opt) {
483                 atomic_sub(opt->tot_len, &sk->sk_omem_alloc);
484                 txopt_put(opt);
485         }
486 }
487 EXPORT_SYMBOL_GPL(inet6_destroy_sock);
488
489 /*
490  *      This does both peername and sockname.
491  */
492
493 int inet6_getname(struct socket *sock, struct sockaddr *uaddr,
494                  int peer)
495 {
496         struct sockaddr_in6 *sin = (struct sockaddr_in6 *)uaddr;
497         struct sock *sk = sock->sk;
498         struct inet_sock *inet = inet_sk(sk);
499         struct ipv6_pinfo *np = inet6_sk(sk);
500
501         sin->sin6_family = AF_INET6;
502         sin->sin6_flowinfo = 0;
503         sin->sin6_scope_id = 0;
504         if (peer) {
505                 if (!inet->inet_dport)
506                         return -ENOTCONN;
507                 if (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
508                     peer == 1)
509                         return -ENOTCONN;
510                 sin->sin6_port = inet->inet_dport;
511                 sin->sin6_addr = sk->sk_v6_daddr;
512                 if (np->sndflow)
513                         sin->sin6_flowinfo = np->flow_label;
514         } else {
515                 if (ipv6_addr_any(&sk->sk_v6_rcv_saddr))
516                         sin->sin6_addr = np->saddr;
517                 else
518                         sin->sin6_addr = sk->sk_v6_rcv_saddr;
519
520                 sin->sin6_port = inet->inet_sport;
521         }
522         sin->sin6_scope_id = ipv6_iface_scope_id(&sin->sin6_addr,
523                                                  sk->sk_bound_dev_if);
524         return sizeof(*sin);
525 }
526 EXPORT_SYMBOL(inet6_getname);
527
528 int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
529 {
530         struct sock *sk = sock->sk;
531         struct net *net = sock_net(sk);
532
533         switch (cmd) {
534         case SIOCGSTAMP:
535                 return sock_get_timestamp(sk, (struct timeval __user *)arg);
536
537         case SIOCGSTAMPNS:
538                 return sock_get_timestampns(sk, (struct timespec __user *)arg);
539
540         case SIOCADDRT:
541         case SIOCDELRT:
542
543                 return ipv6_route_ioctl(net, cmd, (void __user *)arg);
544
545         case SIOCSIFADDR:
546                 return addrconf_add_ifaddr(net, (void __user *) arg);
547         case SIOCDIFADDR:
548                 return addrconf_del_ifaddr(net, (void __user *) arg);
549         case SIOCSIFDSTADDR:
550                 return addrconf_set_dstaddr(net, (void __user *) arg);
551         default:
552                 if (!sk->sk_prot->ioctl)
553                         return -ENOIOCTLCMD;
554                 return sk->sk_prot->ioctl(sk, cmd, arg);
555         }
556         /*NOTREACHED*/
557         return 0;
558 }
559 EXPORT_SYMBOL(inet6_ioctl);
560
561 const struct proto_ops inet6_stream_ops = {
562         .family            = PF_INET6,
563         .owner             = THIS_MODULE,
564         .release           = inet6_release,
565         .bind              = inet6_bind,
566         .connect           = inet_stream_connect,       /* ok           */
567         .socketpair        = sock_no_socketpair,        /* a do nothing */
568         .accept            = inet_accept,               /* ok           */
569         .getname           = inet6_getname,
570         .poll              = tcp_poll,                  /* ok           */
571         .ioctl             = inet6_ioctl,               /* must change  */
572         .listen            = inet_listen,               /* ok           */
573         .shutdown          = inet_shutdown,             /* ok           */
574         .setsockopt        = sock_common_setsockopt,    /* ok           */
575         .getsockopt        = sock_common_getsockopt,    /* ok           */
576         .sendmsg           = inet_sendmsg,              /* ok           */
577         .recvmsg           = inet_recvmsg,              /* ok           */
578 #ifdef CONFIG_MMU
579         .mmap              = tcp_mmap,
580 #endif
581         .sendpage          = inet_sendpage,
582         .sendmsg_locked    = tcp_sendmsg_locked,
583         .sendpage_locked   = tcp_sendpage_locked,
584         .splice_read       = tcp_splice_read,
585         .read_sock         = tcp_read_sock,
586         .peek_len          = tcp_peek_len,
587 #ifdef CONFIG_COMPAT
588         .compat_setsockopt = compat_sock_common_setsockopt,
589         .compat_getsockopt = compat_sock_common_getsockopt,
590 #endif
591         .set_rcvlowat      = tcp_set_rcvlowat,
592 };
593
594 const struct proto_ops inet6_dgram_ops = {
595         .family            = PF_INET6,
596         .owner             = THIS_MODULE,
597         .release           = inet6_release,
598         .bind              = inet6_bind,
599         .connect           = inet_dgram_connect,        /* ok           */
600         .socketpair        = sock_no_socketpair,        /* a do nothing */
601         .accept            = sock_no_accept,            /* a do nothing */
602         .getname           = inet6_getname,
603         .poll              = udp_poll,                  /* ok           */
604         .ioctl             = inet6_ioctl,               /* must change  */
605         .listen            = sock_no_listen,            /* ok           */
606         .shutdown          = inet_shutdown,             /* ok           */
607         .setsockopt        = sock_common_setsockopt,    /* ok           */
608         .getsockopt        = sock_common_getsockopt,    /* ok           */
609         .sendmsg           = inet_sendmsg,              /* ok           */
610         .recvmsg           = inet_recvmsg,              /* ok           */
611         .mmap              = sock_no_mmap,
612         .sendpage          = sock_no_sendpage,
613         .set_peek_off      = sk_set_peek_off,
614 #ifdef CONFIG_COMPAT
615         .compat_setsockopt = compat_sock_common_setsockopt,
616         .compat_getsockopt = compat_sock_common_getsockopt,
617 #endif
618 };
619
620 static const struct net_proto_family inet6_family_ops = {
621         .family = PF_INET6,
622         .create = inet6_create,
623         .owner  = THIS_MODULE,
624 };
625
626 int inet6_register_protosw(struct inet_protosw *p)
627 {
628         struct list_head *lh;
629         struct inet_protosw *answer;
630         struct list_head *last_perm;
631         int protocol = p->protocol;
632         int ret;
633
634         spin_lock_bh(&inetsw6_lock);
635
636         ret = -EINVAL;
637         if (p->type >= SOCK_MAX)
638                 goto out_illegal;
639
640         /* If we are trying to override a permanent protocol, bail. */
641         answer = NULL;
642         ret = -EPERM;
643         last_perm = &inetsw6[p->type];
644         list_for_each(lh, &inetsw6[p->type]) {
645                 answer = list_entry(lh, struct inet_protosw, list);
646
647                 /* Check only the non-wild match. */
648                 if (INET_PROTOSW_PERMANENT & answer->flags) {
649                         if (protocol == answer->protocol)
650                                 break;
651                         last_perm = lh;
652                 }
653
654                 answer = NULL;
655         }
656         if (answer)
657                 goto out_permanent;
658
659         /* Add the new entry after the last permanent entry if any, so that
660          * the new entry does not override a permanent entry when matched with
661          * a wild-card protocol. But it is allowed to override any existing
662          * non-permanent entry.  This means that when we remove this entry, the
663          * system automatically returns to the old behavior.
664          */
665         list_add_rcu(&p->list, last_perm);
666         ret = 0;
667 out:
668         spin_unlock_bh(&inetsw6_lock);
669         return ret;
670
671 out_permanent:
672         pr_err("Attempt to override permanent protocol %d\n", protocol);
673         goto out;
674
675 out_illegal:
676         pr_err("Ignoring attempt to register invalid socket type %d\n",
677                p->type);
678         goto out;
679 }
680 EXPORT_SYMBOL(inet6_register_protosw);
681
682 void
683 inet6_unregister_protosw(struct inet_protosw *p)
684 {
685         if (INET_PROTOSW_PERMANENT & p->flags) {
686                 pr_err("Attempt to unregister permanent protocol %d\n",
687                        p->protocol);
688         } else {
689                 spin_lock_bh(&inetsw6_lock);
690                 list_del_rcu(&p->list);
691                 spin_unlock_bh(&inetsw6_lock);
692
693                 synchronize_net();
694         }
695 }
696 EXPORT_SYMBOL(inet6_unregister_protosw);
697
698 int inet6_sk_rebuild_header(struct sock *sk)
699 {
700         struct ipv6_pinfo *np = inet6_sk(sk);
701         struct dst_entry *dst;
702
703         dst = __sk_dst_check(sk, np->dst_cookie);
704
705         if (!dst) {
706                 struct inet_sock *inet = inet_sk(sk);
707                 struct in6_addr *final_p, final;
708                 struct flowi6 fl6;
709
710                 memset(&fl6, 0, sizeof(fl6));
711                 fl6.flowi6_proto = sk->sk_protocol;
712                 fl6.daddr = sk->sk_v6_daddr;
713                 fl6.saddr = np->saddr;
714                 fl6.flowlabel = np->flow_label;
715                 fl6.flowi6_oif = sk->sk_bound_dev_if;
716                 fl6.flowi6_mark = sk->sk_mark;
717                 fl6.fl6_dport = inet->inet_dport;
718                 fl6.fl6_sport = inet->inet_sport;
719                 fl6.flowi6_uid = sk->sk_uid;
720                 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
721
722                 rcu_read_lock();
723                 final_p = fl6_update_dst(&fl6, rcu_dereference(np->opt),
724                                          &final);
725                 rcu_read_unlock();
726
727                 dst = ip6_dst_lookup_flow(sk, &fl6, final_p);
728                 if (IS_ERR(dst)) {
729                         sk->sk_route_caps = 0;
730                         sk->sk_err_soft = -PTR_ERR(dst);
731                         return PTR_ERR(dst);
732                 }
733
734                 ip6_dst_store(sk, dst, NULL, NULL);
735         }
736
737         return 0;
738 }
739 EXPORT_SYMBOL_GPL(inet6_sk_rebuild_header);
740
741 bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb,
742                        const struct inet6_skb_parm *opt)
743 {
744         const struct ipv6_pinfo *np = inet6_sk(sk);
745
746         if (np->rxopt.all) {
747                 if (((opt->flags & IP6SKB_HOPBYHOP) &&
748                      (np->rxopt.bits.hopopts || np->rxopt.bits.ohopopts)) ||
749                     (ip6_flowinfo((struct ipv6hdr *) skb_network_header(skb)) &&
750                      np->rxopt.bits.rxflow) ||
751                     (opt->srcrt && (np->rxopt.bits.srcrt ||
752                      np->rxopt.bits.osrcrt)) ||
753                     ((opt->dst1 || opt->dst0) &&
754                      (np->rxopt.bits.dstopts || np->rxopt.bits.odstopts)))
755                         return true;
756         }
757         return false;
758 }
759 EXPORT_SYMBOL_GPL(ipv6_opt_accepted);
760
761 static struct packet_type ipv6_packet_type __read_mostly = {
762         .type = cpu_to_be16(ETH_P_IPV6),
763         .func = ipv6_rcv,
764         .list_func = ipv6_list_rcv,
765 };
766
767 static int __init ipv6_packet_init(void)
768 {
769         dev_add_pack(&ipv6_packet_type);
770         return 0;
771 }
772
773 static void ipv6_packet_cleanup(void)
774 {
775         dev_remove_pack(&ipv6_packet_type);
776 }
777
778 static int __net_init ipv6_init_mibs(struct net *net)
779 {
780         int i;
781
782         net->mib.udp_stats_in6 = alloc_percpu(struct udp_mib);
783         if (!net->mib.udp_stats_in6)
784                 return -ENOMEM;
785         net->mib.udplite_stats_in6 = alloc_percpu(struct udp_mib);
786         if (!net->mib.udplite_stats_in6)
787                 goto err_udplite_mib;
788         net->mib.ipv6_statistics = alloc_percpu(struct ipstats_mib);
789         if (!net->mib.ipv6_statistics)
790                 goto err_ip_mib;
791
792         for_each_possible_cpu(i) {
793                 struct ipstats_mib *af_inet6_stats;
794                 af_inet6_stats = per_cpu_ptr(net->mib.ipv6_statistics, i);
795                 u64_stats_init(&af_inet6_stats->syncp);
796         }
797
798
799         net->mib.icmpv6_statistics = alloc_percpu(struct icmpv6_mib);
800         if (!net->mib.icmpv6_statistics)
801                 goto err_icmp_mib;
802         net->mib.icmpv6msg_statistics = kzalloc(sizeof(struct icmpv6msg_mib),
803                                                 GFP_KERNEL);
804         if (!net->mib.icmpv6msg_statistics)
805                 goto err_icmpmsg_mib;
806         return 0;
807
808 err_icmpmsg_mib:
809         free_percpu(net->mib.icmpv6_statistics);
810 err_icmp_mib:
811         free_percpu(net->mib.ipv6_statistics);
812 err_ip_mib:
813         free_percpu(net->mib.udplite_stats_in6);
814 err_udplite_mib:
815         free_percpu(net->mib.udp_stats_in6);
816         return -ENOMEM;
817 }
818
819 static void ipv6_cleanup_mibs(struct net *net)
820 {
821         free_percpu(net->mib.udp_stats_in6);
822         free_percpu(net->mib.udplite_stats_in6);
823         free_percpu(net->mib.ipv6_statistics);
824         free_percpu(net->mib.icmpv6_statistics);
825         kfree(net->mib.icmpv6msg_statistics);
826 }
827
828 static int __net_init inet6_net_init(struct net *net)
829 {
830         int err = 0;
831
832         net->ipv6.sysctl.bindv6only = 0;
833         net->ipv6.sysctl.icmpv6_time = 1*HZ;
834         net->ipv6.sysctl.icmpv6_echo_ignore_all = 0;
835         net->ipv6.sysctl.flowlabel_consistency = 1;
836         net->ipv6.sysctl.auto_flowlabels = IP6_DEFAULT_AUTO_FLOW_LABELS;
837         net->ipv6.sysctl.idgen_retries = 3;
838         net->ipv6.sysctl.idgen_delay = 1 * HZ;
839         net->ipv6.sysctl.flowlabel_state_ranges = 0;
840         net->ipv6.sysctl.max_dst_opts_cnt = IP6_DEFAULT_MAX_DST_OPTS_CNT;
841         net->ipv6.sysctl.max_hbh_opts_cnt = IP6_DEFAULT_MAX_HBH_OPTS_CNT;
842         net->ipv6.sysctl.max_dst_opts_len = IP6_DEFAULT_MAX_DST_OPTS_LEN;
843         net->ipv6.sysctl.max_hbh_opts_len = IP6_DEFAULT_MAX_HBH_OPTS_LEN;
844         atomic_set(&net->ipv6.fib6_sernum, 1);
845
846         err = ipv6_init_mibs(net);
847         if (err)
848                 return err;
849 #ifdef CONFIG_PROC_FS
850         err = udp6_proc_init(net);
851         if (err)
852                 goto out;
853         err = tcp6_proc_init(net);
854         if (err)
855                 goto proc_tcp6_fail;
856         err = ac6_proc_init(net);
857         if (err)
858                 goto proc_ac6_fail;
859 #endif
860         return err;
861
862 #ifdef CONFIG_PROC_FS
863 proc_ac6_fail:
864         tcp6_proc_exit(net);
865 proc_tcp6_fail:
866         udp6_proc_exit(net);
867 out:
868         ipv6_cleanup_mibs(net);
869         return err;
870 #endif
871 }
872
873 static void __net_exit inet6_net_exit(struct net *net)
874 {
875 #ifdef CONFIG_PROC_FS
876         udp6_proc_exit(net);
877         tcp6_proc_exit(net);
878         ac6_proc_exit(net);
879 #endif
880         ipv6_cleanup_mibs(net);
881 }
882
883 static struct pernet_operations inet6_net_ops = {
884         .init = inet6_net_init,
885         .exit = inet6_net_exit,
886 };
887
888 static const struct ipv6_stub ipv6_stub_impl = {
889         .ipv6_sock_mc_join = ipv6_sock_mc_join,
890         .ipv6_sock_mc_drop = ipv6_sock_mc_drop,
891         .ipv6_dst_lookup   = ip6_dst_lookup,
892         .fib6_get_table    = fib6_get_table,
893         .fib6_table_lookup = fib6_table_lookup,
894         .fib6_lookup       = fib6_lookup,
895         .fib6_multipath_select = fib6_multipath_select,
896         .ip6_mtu_from_fib6 = ip6_mtu_from_fib6,
897         .udpv6_encap_enable = udpv6_encap_enable,
898         .ndisc_send_na = ndisc_send_na,
899         .nd_tbl = &nd_tbl,
900 };
901
902 static const struct ipv6_bpf_stub ipv6_bpf_stub_impl = {
903         .inet6_bind = __inet6_bind,
904         .udp6_lib_lookup = __udp6_lib_lookup,
905 };
906
907 static int __init inet6_init(void)
908 {
909         struct list_head *r;
910         int err = 0;
911
912         sock_skb_cb_check_size(sizeof(struct inet6_skb_parm));
913
914         /* Register the socket-side information for inet6_create.  */
915         for (r = &inetsw6[0]; r < &inetsw6[SOCK_MAX]; ++r)
916                 INIT_LIST_HEAD(r);
917
918         if (disable_ipv6_mod) {
919                 pr_info("Loaded, but administratively disabled, reboot required to enable\n");
920                 goto out;
921         }
922
923         err = proto_register(&tcpv6_prot, 1);
924         if (err)
925                 goto out;
926
927         err = proto_register(&udpv6_prot, 1);
928         if (err)
929                 goto out_unregister_tcp_proto;
930
931         err = proto_register(&udplitev6_prot, 1);
932         if (err)
933                 goto out_unregister_udp_proto;
934
935         err = proto_register(&rawv6_prot, 1);
936         if (err)
937                 goto out_unregister_udplite_proto;
938
939         err = proto_register(&pingv6_prot, 1);
940         if (err)
941                 goto out_unregister_raw_proto;
942
943         /* We MUST register RAW sockets before we create the ICMP6,
944          * IGMP6, or NDISC control sockets.
945          */
946         err = rawv6_init();
947         if (err)
948                 goto out_unregister_ping_proto;
949
950         /* Register the family here so that the init calls below will
951          * be able to create sockets. (?? is this dangerous ??)
952          */
953         err = sock_register(&inet6_family_ops);
954         if (err)
955                 goto out_sock_register_fail;
956
957         /*
958          *      ipngwg API draft makes clear that the correct semantics
959          *      for TCP and UDP is to consider one TCP and UDP instance
960          *      in a host available by both INET and INET6 APIs and
961          *      able to communicate via both network protocols.
962          */
963
964         err = register_pernet_subsys(&inet6_net_ops);
965         if (err)
966                 goto register_pernet_fail;
967         err = ip6_mr_init();
968         if (err)
969                 goto ipmr_fail;
970         err = icmpv6_init();
971         if (err)
972                 goto icmp_fail;
973         err = ndisc_init();
974         if (err)
975                 goto ndisc_fail;
976         err = igmp6_init();
977         if (err)
978                 goto igmp_fail;
979
980         err = ipv6_netfilter_init();
981         if (err)
982                 goto netfilter_fail;
983         /* Create /proc/foo6 entries. */
984 #ifdef CONFIG_PROC_FS
985         err = -ENOMEM;
986         if (raw6_proc_init())
987                 goto proc_raw6_fail;
988         if (udplite6_proc_init())
989                 goto proc_udplite6_fail;
990         if (ipv6_misc_proc_init())
991                 goto proc_misc6_fail;
992         if (if6_proc_init())
993                 goto proc_if6_fail;
994 #endif
995         err = ip6_route_init();
996         if (err)
997                 goto ip6_route_fail;
998         err = ndisc_late_init();
999         if (err)
1000                 goto ndisc_late_fail;
1001         err = ip6_flowlabel_init();
1002         if (err)
1003                 goto ip6_flowlabel_fail;
1004         err = ipv6_anycast_init();
1005         if (err)
1006                 goto ipv6_anycast_fail;
1007         err = addrconf_init();
1008         if (err)
1009                 goto addrconf_fail;
1010
1011         /* Init v6 extension headers. */
1012         err = ipv6_exthdrs_init();
1013         if (err)
1014                 goto ipv6_exthdrs_fail;
1015
1016         err = ipv6_frag_init();
1017         if (err)
1018                 goto ipv6_frag_fail;
1019
1020         /* Init v6 transport protocols. */
1021         err = udpv6_init();
1022         if (err)
1023                 goto udpv6_fail;
1024
1025         err = udplitev6_init();
1026         if (err)
1027                 goto udplitev6_fail;
1028
1029         err = udpv6_offload_init();
1030         if (err)
1031                 goto udpv6_offload_fail;
1032
1033         err = tcpv6_init();
1034         if (err)
1035                 goto tcpv6_fail;
1036
1037         err = ipv6_packet_init();
1038         if (err)
1039                 goto ipv6_packet_fail;
1040
1041         err = pingv6_init();
1042         if (err)
1043                 goto pingv6_fail;
1044
1045         err = calipso_init();
1046         if (err)
1047                 goto calipso_fail;
1048
1049         err = seg6_init();
1050         if (err)
1051                 goto seg6_fail;
1052
1053         err = igmp6_late_init();
1054         if (err)
1055                 goto igmp6_late_err;
1056
1057 #ifdef CONFIG_SYSCTL
1058         err = ipv6_sysctl_register();
1059         if (err)
1060                 goto sysctl_fail;
1061 #endif
1062
1063         /* ensure that ipv6 stubs are visible only after ipv6 is ready */
1064         wmb();
1065         ipv6_stub = &ipv6_stub_impl;
1066         ipv6_bpf_stub = &ipv6_bpf_stub_impl;
1067 out:
1068         return err;
1069
1070 #ifdef CONFIG_SYSCTL
1071 sysctl_fail:
1072         igmp6_late_cleanup();
1073 #endif
1074 igmp6_late_err:
1075         seg6_exit();
1076 seg6_fail:
1077         calipso_exit();
1078 calipso_fail:
1079         pingv6_exit();
1080 pingv6_fail:
1081         ipv6_packet_cleanup();
1082 ipv6_packet_fail:
1083         tcpv6_exit();
1084 tcpv6_fail:
1085         udpv6_offload_exit();
1086 udpv6_offload_fail:
1087         udplitev6_exit();
1088 udplitev6_fail:
1089         udpv6_exit();
1090 udpv6_fail:
1091         ipv6_frag_exit();
1092 ipv6_frag_fail:
1093         ipv6_exthdrs_exit();
1094 ipv6_exthdrs_fail:
1095         addrconf_cleanup();
1096 addrconf_fail:
1097         ipv6_anycast_cleanup();
1098 ipv6_anycast_fail:
1099         ip6_flowlabel_cleanup();
1100 ip6_flowlabel_fail:
1101         ndisc_late_cleanup();
1102 ndisc_late_fail:
1103         ip6_route_cleanup();
1104 ip6_route_fail:
1105 #ifdef CONFIG_PROC_FS
1106         if6_proc_exit();
1107 proc_if6_fail:
1108         ipv6_misc_proc_exit();
1109 proc_misc6_fail:
1110         udplite6_proc_exit();
1111 proc_udplite6_fail:
1112         raw6_proc_exit();
1113 proc_raw6_fail:
1114 #endif
1115         ipv6_netfilter_fini();
1116 netfilter_fail:
1117         igmp6_cleanup();
1118 igmp_fail:
1119         ndisc_cleanup();
1120 ndisc_fail:
1121         icmpv6_cleanup();
1122 icmp_fail:
1123         ip6_mr_cleanup();
1124 ipmr_fail:
1125         unregister_pernet_subsys(&inet6_net_ops);
1126 register_pernet_fail:
1127         sock_unregister(PF_INET6);
1128         rtnl_unregister_all(PF_INET6);
1129 out_sock_register_fail:
1130         rawv6_exit();
1131 out_unregister_ping_proto:
1132         proto_unregister(&pingv6_prot);
1133 out_unregister_raw_proto:
1134         proto_unregister(&rawv6_prot);
1135 out_unregister_udplite_proto:
1136         proto_unregister(&udplitev6_prot);
1137 out_unregister_udp_proto:
1138         proto_unregister(&udpv6_prot);
1139 out_unregister_tcp_proto:
1140         proto_unregister(&tcpv6_prot);
1141         goto out;
1142 }
1143 module_init(inet6_init);
1144
1145 MODULE_ALIAS_NETPROTO(PF_INET6);