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af_inet6.c
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1 /*
2  * PF_INET6 socket protocol family
3  * Linux INET6 implementation
4  *
5  * Authors:
6  * Pedro Roque <[email protected]>
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/ipip.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 #ifdef CONFIG_IPV6_TUNNEL
60 #include <net/ip6_tunnel.h>
61 #endif
62 
63 #include <asm/uaccess.h>
64 #include <linux/mroute6.h>
65 
66 MODULE_AUTHOR("Cast of dozens");
67 MODULE_DESCRIPTION("IPv6 protocol stack for Linux");
68 MODULE_LICENSE("GPL");
69 
70 /* The inetsw6 table contains everything that inet6_create needs to
71  * build a new socket.
72  */
73 static struct list_head inetsw6[SOCK_MAX];
74 static DEFINE_SPINLOCK(inetsw6_lock);
75 
76 struct ipv6_params ipv6_defaults = {
77  .disable_ipv6 = 0,
78  .autoconf = 1,
79 };
80 
81 static int disable_ipv6_mod;
82 
83 module_param_named(disable, disable_ipv6_mod, int, 0444);
84 MODULE_PARM_DESC(disable, "Disable IPv6 module such that it is non-functional");
85 
86 module_param_named(disable_ipv6, ipv6_defaults.disable_ipv6, int, 0444);
87 MODULE_PARM_DESC(disable_ipv6, "Disable IPv6 on all interfaces");
88 
89 module_param_named(autoconf, ipv6_defaults.autoconf, int, 0444);
90 MODULE_PARM_DESC(autoconf, "Enable IPv6 address autoconfiguration on all interfaces");
91 
92 static __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 
99 static 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. */
118 lookup_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 = SK_CAN_REUSE;
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  inet->rcv_tos = 0;
218 
219  if (ipv4_config.no_pmtu_disc)
220  inet->pmtudisc = IP_PMTUDISC_DONT;
221  else
222  inet->pmtudisc = IP_PMTUDISC_WANT;
223  /*
224  * Increment only the relevant sk_prot->socks debug field, this changes
225  * the previous behaviour of incrementing both the equivalent to
226  * answer->prot->socks (inet6_sock_nr) and inet_sock_nr.
227  *
228  * This allows better debug granularity as we'll know exactly how many
229  * UDPv6, TCPv6, etc socks were allocated, not the sum of all IPv6
230  * transport protocol socks. -acme
231  */
232  sk_refcnt_debug_inc(sk);
233 
234  if (inet->inet_num) {
235  /* It assumes that any protocol which allows
236  * the user to assign a number at socket
237  * creation time automatically shares.
238  */
239  inet->inet_sport = htons(inet->inet_num);
240  sk->sk_prot->hash(sk);
241  }
242  if (sk->sk_prot->init) {
243  err = sk->sk_prot->init(sk);
244  if (err) {
245  sk_common_release(sk);
246  goto out;
247  }
248  }
249 out:
250  return err;
251 out_rcu_unlock:
252  rcu_read_unlock();
253  goto out;
254 }
255 
256 
257 /* bind for INET6 API */
258 int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
259 {
260  struct sockaddr_in6 *addr = (struct sockaddr_in6 *)uaddr;
261  struct sock *sk = sock->sk;
262  struct inet_sock *inet = inet_sk(sk);
263  struct ipv6_pinfo *np = inet6_sk(sk);
264  struct net *net = sock_net(sk);
265  __be32 v4addr = 0;
266  unsigned short snum;
267  int addr_type = 0;
268  int err = 0;
269 
270  /* If the socket has its own bind function then use it. */
271  if (sk->sk_prot->bind)
272  return sk->sk_prot->bind(sk, uaddr, addr_len);
273 
274  if (addr_len < SIN6_LEN_RFC2133)
275  return -EINVAL;
276 
277  if (addr->sin6_family != AF_INET6)
278  return -EAFNOSUPPORT;
279 
280  addr_type = ipv6_addr_type(&addr->sin6_addr);
281  if ((addr_type & IPV6_ADDR_MULTICAST) && sock->type == SOCK_STREAM)
282  return -EINVAL;
283 
284  snum = ntohs(addr->sin6_port);
285  if (snum && snum < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE))
286  return -EACCES;
287 
288  lock_sock(sk);
289 
290  /* Check these errors (active socket, double bind). */
291  if (sk->sk_state != TCP_CLOSE || inet->inet_num) {
292  err = -EINVAL;
293  goto out;
294  }
295 
296  /* Check if the address belongs to the host. */
297  if (addr_type == IPV6_ADDR_MAPPED) {
298  int chk_addr_ret;
299 
300  /* Binding to v4-mapped address on a v6-only socket
301  * makes no sense
302  */
303  if (np->ipv6only) {
304  err = -EINVAL;
305  goto out;
306  }
307 
308  /* Reproduce AF_INET checks to make the bindings consistent */
309  v4addr = addr->sin6_addr.s6_addr32[3];
310  chk_addr_ret = inet_addr_type(net, v4addr);
311  if (!sysctl_ip_nonlocal_bind &&
312  !(inet->freebind || inet->transparent) &&
313  v4addr != htonl(INADDR_ANY) &&
314  chk_addr_ret != RTN_LOCAL &&
315  chk_addr_ret != RTN_MULTICAST &&
316  chk_addr_ret != RTN_BROADCAST) {
317  err = -EADDRNOTAVAIL;
318  goto out;
319  }
320  } else {
321  if (addr_type != IPV6_ADDR_ANY) {
322  struct net_device *dev = NULL;
323 
324  rcu_read_lock();
325  if (addr_type & IPV6_ADDR_LINKLOCAL) {
326  if (addr_len >= sizeof(struct sockaddr_in6) &&
327  addr->sin6_scope_id) {
328  /* Override any existing binding, if another one
329  * is supplied by user.
330  */
331  sk->sk_bound_dev_if = addr->sin6_scope_id;
332  }
333 
334  /* Binding to link-local address requires an interface */
335  if (!sk->sk_bound_dev_if) {
336  err = -EINVAL;
337  goto out_unlock;
338  }
339  dev = dev_get_by_index_rcu(net, sk->sk_bound_dev_if);
340  if (!dev) {
341  err = -ENODEV;
342  goto out_unlock;
343  }
344  }
345 
346  /* ipv4 addr of the socket is invalid. Only the
347  * unspecified and mapped address have a v4 equivalent.
348  */
349  v4addr = LOOPBACK4_IPV6;
350  if (!(addr_type & IPV6_ADDR_MULTICAST)) {
351  if (!(inet->freebind || inet->transparent) &&
352  !ipv6_chk_addr(net, &addr->sin6_addr,
353  dev, 0)) {
354  err = -EADDRNOTAVAIL;
355  goto out_unlock;
356  }
357  }
358  rcu_read_unlock();
359  }
360  }
361 
362  inet->inet_rcv_saddr = v4addr;
363  inet->inet_saddr = v4addr;
364 
365  np->rcv_saddr = addr->sin6_addr;
366 
367  if (!(addr_type & IPV6_ADDR_MULTICAST))
368  np->saddr = addr->sin6_addr;
369 
370  /* Make sure we are allowed to bind here. */
371  if (sk->sk_prot->get_port(sk, snum)) {
372  inet_reset_saddr(sk);
373  err = -EADDRINUSE;
374  goto out;
375  }
376 
377  if (addr_type != IPV6_ADDR_ANY) {
378  sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
379  if (addr_type != IPV6_ADDR_MAPPED)
380  np->ipv6only = 1;
381  }
382  if (snum)
383  sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
384  inet->inet_sport = htons(inet->inet_num);
385  inet->inet_dport = 0;
386  inet->inet_daddr = 0;
387 out:
388  release_sock(sk);
389  return err;
390 out_unlock:
391  rcu_read_unlock();
392  goto out;
393 }
394 EXPORT_SYMBOL(inet6_bind);
395 
396 int 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 EXPORT_SYMBOL(inet6_release);
412 
413 void inet6_destroy_sock(struct sock *sk)
414 {
415  struct ipv6_pinfo *np = inet6_sk(sk);
416  struct sk_buff *skb;
417  struct ipv6_txoptions *opt;
418 
419  /* Release rx options */
420 
421  skb = xchg(&np->pktoptions, NULL);
422  if (skb != NULL)
423  kfree_skb(skb);
424 
425  skb = xchg(&np->rxpmtu, NULL);
426  if (skb != NULL)
427  kfree_skb(skb);
428 
429  /* Free flowlabels */
430  fl6_free_socklist(sk);
431 
432  /* Free tx options */
433 
434  opt = xchg(&np->opt, NULL);
435  if (opt != NULL)
436  sock_kfree_s(sk, opt, opt->tot_len);
437 }
438 EXPORT_SYMBOL_GPL(inet6_destroy_sock);
439 
440 /*
441  * This does both peername and sockname.
442  */
443 
444 int inet6_getname(struct socket *sock, struct sockaddr *uaddr,
445  int *uaddr_len, int peer)
446 {
447  struct sockaddr_in6 *sin = (struct sockaddr_in6 *)uaddr;
448  struct sock *sk = sock->sk;
449  struct inet_sock *inet = inet_sk(sk);
450  struct ipv6_pinfo *np = inet6_sk(sk);
451 
452  sin->sin6_family = AF_INET6;
453  sin->sin6_flowinfo = 0;
454  sin->sin6_scope_id = 0;
455  if (peer) {
456  if (!inet->inet_dport)
457  return -ENOTCONN;
458  if (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
459  peer == 1)
460  return -ENOTCONN;
461  sin->sin6_port = inet->inet_dport;
462  sin->sin6_addr = np->daddr;
463  if (np->sndflow)
464  sin->sin6_flowinfo = np->flow_label;
465  } else {
466  if (ipv6_addr_any(&np->rcv_saddr))
467  sin->sin6_addr = np->saddr;
468  else
469  sin->sin6_addr = np->rcv_saddr;
470 
471  sin->sin6_port = inet->inet_sport;
472  }
473  if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
474  sin->sin6_scope_id = sk->sk_bound_dev_if;
475  *uaddr_len = sizeof(*sin);
476  return 0;
477 }
478 EXPORT_SYMBOL(inet6_getname);
479 
480 int 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  case SIOCGSTAMP:
487  return sock_get_timestamp(sk, (struct timeval __user *)arg);
488 
489  case SIOCGSTAMPNS:
490  return sock_get_timestampns(sk, (struct timespec __user *)arg);
491 
492  case SIOCADDRT:
493  case SIOCDELRT:
494 
495  return ipv6_route_ioctl(net, cmd, (void __user *)arg);
496 
497  case SIOCSIFADDR:
498  return addrconf_add_ifaddr(net, (void __user *) arg);
499  case SIOCDIFADDR:
500  return addrconf_del_ifaddr(net, (void __user *) arg);
501  case SIOCSIFDSTADDR:
502  return addrconf_set_dstaddr(net, (void __user *) arg);
503  default:
504  if (!sk->sk_prot->ioctl)
505  return -ENOIOCTLCMD;
506  return sk->sk_prot->ioctl(sk, cmd, arg);
507  }
508  /*NOTREACHED*/
509  return 0;
510 }
511 EXPORT_SYMBOL(inet6_ioctl);
512 
513 const struct proto_ops inet6_stream_ops = {
514  .family = PF_INET6,
515  .owner = THIS_MODULE,
516  .release = inet6_release,
517  .bind = inet6_bind,
518  .connect = inet_stream_connect, /* ok */
519  .socketpair = sock_no_socketpair, /* a do nothing */
520  .accept = inet_accept, /* ok */
521  .getname = inet6_getname,
522  .poll = tcp_poll, /* ok */
523  .ioctl = inet6_ioctl, /* must change */
524  .listen = inet_listen, /* ok */
525  .shutdown = inet_shutdown, /* ok */
526  .setsockopt = sock_common_setsockopt, /* ok */
527  .getsockopt = sock_common_getsockopt, /* ok */
528  .sendmsg = inet_sendmsg, /* ok */
529  .recvmsg = inet_recvmsg, /* ok */
530  .mmap = sock_no_mmap,
531  .sendpage = inet_sendpage,
532  .splice_read = tcp_splice_read,
533 #ifdef CONFIG_COMPAT
534  .compat_setsockopt = compat_sock_common_setsockopt,
535  .compat_getsockopt = compat_sock_common_getsockopt,
536 #endif
537 };
538 
539 const struct proto_ops inet6_dgram_ops = {
540  .family = PF_INET6,
541  .owner = THIS_MODULE,
542  .release = inet6_release,
543  .bind = inet6_bind,
544  .connect = inet_dgram_connect, /* ok */
545  .socketpair = sock_no_socketpair, /* a do nothing */
546  .accept = sock_no_accept, /* a do nothing */
547  .getname = inet6_getname,
548  .poll = udp_poll, /* ok */
549  .ioctl = inet6_ioctl, /* must change */
550  .listen = sock_no_listen, /* ok */
551  .shutdown = inet_shutdown, /* ok */
552  .setsockopt = sock_common_setsockopt, /* ok */
553  .getsockopt = sock_common_getsockopt, /* ok */
554  .sendmsg = inet_sendmsg, /* ok */
555  .recvmsg = inet_recvmsg, /* ok */
556  .mmap = sock_no_mmap,
557  .sendpage = sock_no_sendpage,
558 #ifdef CONFIG_COMPAT
559  .compat_setsockopt = compat_sock_common_setsockopt,
560  .compat_getsockopt = compat_sock_common_getsockopt,
561 #endif
562 };
563 
564 static const struct net_proto_family inet6_family_ops = {
565  .family = PF_INET6,
566  .create = inet6_create,
567  .owner = THIS_MODULE,
568 };
569 
570 int inet6_register_protosw(struct inet_protosw *p)
571 {
572  struct list_head *lh;
573  struct inet_protosw *answer;
574  struct list_head *last_perm;
575  int protocol = p->protocol;
576  int ret;
577 
578  spin_lock_bh(&inetsw6_lock);
579 
580  ret = -EINVAL;
581  if (p->type >= SOCK_MAX)
582  goto out_illegal;
583 
584  /* If we are trying to override a permanent protocol, bail. */
585  answer = NULL;
586  ret = -EPERM;
587  last_perm = &inetsw6[p->type];
588  list_for_each(lh, &inetsw6[p->type]) {
589  answer = list_entry(lh, struct inet_protosw, list);
590 
591  /* Check only the non-wild match. */
592  if (INET_PROTOSW_PERMANENT & answer->flags) {
593  if (protocol == answer->protocol)
594  break;
595  last_perm = lh;
596  }
597 
598  answer = NULL;
599  }
600  if (answer)
601  goto out_permanent;
602 
603  /* Add the new entry after the last permanent entry if any, so that
604  * the new entry does not override a permanent entry when matched with
605  * a wild-card protocol. But it is allowed to override any existing
606  * non-permanent entry. This means that when we remove this entry, the
607  * system automatically returns to the old behavior.
608  */
609  list_add_rcu(&p->list, last_perm);
610  ret = 0;
611 out:
612  spin_unlock_bh(&inetsw6_lock);
613  return ret;
614 
615 out_permanent:
616  pr_err("Attempt to override permanent protocol %d\n", protocol);
617  goto out;
618 
619 out_illegal:
620  pr_err("Ignoring attempt to register invalid socket type %d\n",
621  p->type);
622  goto out;
623 }
624 EXPORT_SYMBOL(inet6_register_protosw);
625 
626 void
627 inet6_unregister_protosw(struct inet_protosw *p)
628 {
629  if (INET_PROTOSW_PERMANENT & p->flags) {
630  pr_err("Attempt to unregister permanent protocol %d\n",
631  p->protocol);
632  } else {
633  spin_lock_bh(&inetsw6_lock);
634  list_del_rcu(&p->list);
635  spin_unlock_bh(&inetsw6_lock);
636 
637  synchronize_net();
638  }
639 }
640 EXPORT_SYMBOL(inet6_unregister_protosw);
641 
642 int inet6_sk_rebuild_header(struct sock *sk)
643 {
644  struct ipv6_pinfo *np = inet6_sk(sk);
645  struct dst_entry *dst;
646 
647  dst = __sk_dst_check(sk, np->dst_cookie);
648 
649  if (dst == NULL) {
650  struct inet_sock *inet = inet_sk(sk);
651  struct in6_addr *final_p, final;
652  struct flowi6 fl6;
653 
654  memset(&fl6, 0, sizeof(fl6));
655  fl6.flowi6_proto = sk->sk_protocol;
656  fl6.daddr = np->daddr;
657  fl6.saddr = np->saddr;
658  fl6.flowlabel = np->flow_label;
659  fl6.flowi6_oif = sk->sk_bound_dev_if;
660  fl6.flowi6_mark = sk->sk_mark;
661  fl6.fl6_dport = inet->inet_dport;
662  fl6.fl6_sport = inet->inet_sport;
663  security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
664 
665  final_p = fl6_update_dst(&fl6, np->opt, &final);
666 
667  dst = ip6_dst_lookup_flow(sk, &fl6, final_p, false);
668  if (IS_ERR(dst)) {
669  sk->sk_route_caps = 0;
670  sk->sk_err_soft = -PTR_ERR(dst);
671  return PTR_ERR(dst);
672  }
673 
674  __ip6_dst_store(sk, dst, NULL, NULL);
675  }
676 
677  return 0;
678 }
679 EXPORT_SYMBOL_GPL(inet6_sk_rebuild_header);
680 
681 bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb)
682 {
683  const struct ipv6_pinfo *np = inet6_sk(sk);
684  const struct inet6_skb_parm *opt = IP6CB(skb);
685 
686  if (np->rxopt.all) {
687  if ((opt->hop && (np->rxopt.bits.hopopts ||
688  np->rxopt.bits.ohopopts)) ||
689  ((IPV6_FLOWINFO_MASK &
690  *(__be32 *)skb_network_header(skb)) &&
691  np->rxopt.bits.rxflow) ||
692  (opt->srcrt && (np->rxopt.bits.srcrt ||
693  np->rxopt.bits.osrcrt)) ||
694  ((opt->dst1 || opt->dst0) &&
695  (np->rxopt.bits.dstopts || np->rxopt.bits.odstopts)))
696  return true;
697  }
698  return false;
699 }
700 EXPORT_SYMBOL_GPL(ipv6_opt_accepted);
701 
702 static int ipv6_gso_pull_exthdrs(struct sk_buff *skb, int proto)
703 {
704  const struct inet6_protocol *ops = NULL;
705 
706  for (;;) {
707  struct ipv6_opt_hdr *opth;
708  int len;
709 
710  if (proto != NEXTHDR_HOP) {
711  ops = rcu_dereference(inet6_protos[proto]);
712 
713  if (unlikely(!ops))
714  break;
715 
716  if (!(ops->flags & INET6_PROTO_GSO_EXTHDR))
717  break;
718  }
719 
720  if (unlikely(!pskb_may_pull(skb, 8)))
721  break;
722 
723  opth = (void *)skb->data;
724  len = ipv6_optlen(opth);
725 
726  if (unlikely(!pskb_may_pull(skb, len)))
727  break;
728 
729  proto = opth->nexthdr;
730  __skb_pull(skb, len);
731  }
732 
733  return proto;
734 }
735 
736 static int ipv6_gso_send_check(struct sk_buff *skb)
737 {
738  const struct ipv6hdr *ipv6h;
739  const struct inet6_protocol *ops;
740  int err = -EINVAL;
741 
742  if (unlikely(!pskb_may_pull(skb, sizeof(*ipv6h))))
743  goto out;
744 
745  ipv6h = ipv6_hdr(skb);
746  __skb_pull(skb, sizeof(*ipv6h));
747  err = -EPROTONOSUPPORT;
748 
749  rcu_read_lock();
750  ops = rcu_dereference(inet6_protos[
751  ipv6_gso_pull_exthdrs(skb, ipv6h->nexthdr)]);
752 
753  if (likely(ops && ops->gso_send_check)) {
754  skb_reset_transport_header(skb);
755  err = ops->gso_send_check(skb);
756  }
757  rcu_read_unlock();
758 
759 out:
760  return err;
761 }
762 
763 static struct sk_buff *ipv6_gso_segment(struct sk_buff *skb,
764  netdev_features_t features)
765 {
766  struct sk_buff *segs = ERR_PTR(-EINVAL);
767  struct ipv6hdr *ipv6h;
768  const struct inet6_protocol *ops;
769  int proto;
770  struct frag_hdr *fptr;
771  unsigned int unfrag_ip6hlen;
772  u8 *prevhdr;
773  int offset = 0;
774 
775  if (!(features & NETIF_F_V6_CSUM))
776  features &= ~NETIF_F_SG;
777 
778  if (unlikely(skb_shinfo(skb)->gso_type &
779  ~(SKB_GSO_UDP |
780  SKB_GSO_DODGY |
781  SKB_GSO_TCP_ECN |
782  SKB_GSO_TCPV6 |
783  0)))
784  goto out;
785 
786  if (unlikely(!pskb_may_pull(skb, sizeof(*ipv6h))))
787  goto out;
788 
789  ipv6h = ipv6_hdr(skb);
790  __skb_pull(skb, sizeof(*ipv6h));
791  segs = ERR_PTR(-EPROTONOSUPPORT);
792 
793  proto = ipv6_gso_pull_exthdrs(skb, ipv6h->nexthdr);
794  rcu_read_lock();
795  ops = rcu_dereference(inet6_protos[proto]);
796  if (likely(ops && ops->gso_segment)) {
797  skb_reset_transport_header(skb);
798  segs = ops->gso_segment(skb, features);
799  }
800  rcu_read_unlock();
801 
802  if (IS_ERR(segs))
803  goto out;
804 
805  for (skb = segs; skb; skb = skb->next) {
806  ipv6h = ipv6_hdr(skb);
807  ipv6h->payload_len = htons(skb->len - skb->mac_len -
808  sizeof(*ipv6h));
809  if (proto == IPPROTO_UDP) {
810  unfrag_ip6hlen = ip6_find_1stfragopt(skb, &prevhdr);
811  fptr = (struct frag_hdr *)(skb_network_header(skb) +
812  unfrag_ip6hlen);
813  fptr->frag_off = htons(offset);
814  if (skb->next != NULL)
815  fptr->frag_off |= htons(IP6_MF);
816  offset += (ntohs(ipv6h->payload_len) -
817  sizeof(struct frag_hdr));
818  }
819  }
820 
821 out:
822  return segs;
823 }
824 
825 static struct sk_buff **ipv6_gro_receive(struct sk_buff **head,
826  struct sk_buff *skb)
827 {
828  const struct inet6_protocol *ops;
829  struct sk_buff **pp = NULL;
830  struct sk_buff *p;
831  struct ipv6hdr *iph;
832  unsigned int nlen;
833  unsigned int hlen;
834  unsigned int off;
835  int flush = 1;
836  int proto;
837  __wsum csum;
838 
839  off = skb_gro_offset(skb);
840  hlen = off + sizeof(*iph);
841  iph = skb_gro_header_fast(skb, off);
842  if (skb_gro_header_hard(skb, hlen)) {
843  iph = skb_gro_header_slow(skb, hlen, off);
844  if (unlikely(!iph))
845  goto out;
846  }
847 
848  skb_gro_pull(skb, sizeof(*iph));
849  skb_set_transport_header(skb, skb_gro_offset(skb));
850 
851  flush += ntohs(iph->payload_len) != skb_gro_len(skb);
852 
853  rcu_read_lock();
854  proto = iph->nexthdr;
855  ops = rcu_dereference(inet6_protos[proto]);
856  if (!ops || !ops->gro_receive) {
857  __pskb_pull(skb, skb_gro_offset(skb));
858  proto = ipv6_gso_pull_exthdrs(skb, proto);
859  skb_gro_pull(skb, -skb_transport_offset(skb));
860  skb_reset_transport_header(skb);
861  __skb_push(skb, skb_gro_offset(skb));
862 
863  ops = rcu_dereference(inet6_protos[proto]);
864  if (!ops || !ops->gro_receive)
865  goto out_unlock;
866 
867  iph = ipv6_hdr(skb);
868  }
869 
870  NAPI_GRO_CB(skb)->proto = proto;
871 
872  flush--;
873  nlen = skb_network_header_len(skb);
874 
875  for (p = *head; p; p = p->next) {
876  const struct ipv6hdr *iph2;
877  __be32 first_word; /* <Version:4><Traffic_Class:8><Flow_Label:20> */
878 
879  if (!NAPI_GRO_CB(p)->same_flow)
880  continue;
881 
882  iph2 = ipv6_hdr(p);
883  first_word = *(__be32 *)iph ^ *(__be32 *)iph2 ;
884 
885  /* All fields must match except length and Traffic Class. */
886  if (nlen != skb_network_header_len(p) ||
887  (first_word & htonl(0xF00FFFFF)) ||
888  memcmp(&iph->nexthdr, &iph2->nexthdr,
889  nlen - offsetof(struct ipv6hdr, nexthdr))) {
890  NAPI_GRO_CB(p)->same_flow = 0;
891  continue;
892  }
893  /* flush if Traffic Class fields are different */
894  NAPI_GRO_CB(p)->flush |= !!(first_word & htonl(0x0FF00000));
895  NAPI_GRO_CB(p)->flush |= flush;
896  }
897 
898  NAPI_GRO_CB(skb)->flush |= flush;
899 
900  csum = skb->csum;
901  skb_postpull_rcsum(skb, iph, skb_network_header_len(skb));
902 
903  pp = ops->gro_receive(head, skb);
904 
905  skb->csum = csum;
906 
907 out_unlock:
908  rcu_read_unlock();
909 
910 out:
911  NAPI_GRO_CB(skb)->flush |= flush;
912 
913  return pp;
914 }
915 
916 static int ipv6_gro_complete(struct sk_buff *skb)
917 {
918  const struct inet6_protocol *ops;
919  struct ipv6hdr *iph = ipv6_hdr(skb);
920  int err = -ENOSYS;
921 
922  iph->payload_len = htons(skb->len - skb_network_offset(skb) -
923  sizeof(*iph));
924 
925  rcu_read_lock();
926  ops = rcu_dereference(inet6_protos[NAPI_GRO_CB(skb)->proto]);
927  if (WARN_ON(!ops || !ops->gro_complete))
928  goto out_unlock;
929 
930  err = ops->gro_complete(skb);
931 
932 out_unlock:
933  rcu_read_unlock();
934 
935  return err;
936 }
937 
938 static struct packet_type ipv6_packet_type __read_mostly = {
939  .type = cpu_to_be16(ETH_P_IPV6),
940  .func = ipv6_rcv,
941  .gso_send_check = ipv6_gso_send_check,
942  .gso_segment = ipv6_gso_segment,
943  .gro_receive = ipv6_gro_receive,
944  .gro_complete = ipv6_gro_complete,
945 };
946 
947 static int __init ipv6_packet_init(void)
948 {
949  dev_add_pack(&ipv6_packet_type);
950  return 0;
951 }
952 
953 static void ipv6_packet_cleanup(void)
954 {
955  dev_remove_pack(&ipv6_packet_type);
956 }
957 
958 static int __net_init ipv6_init_mibs(struct net *net)
959 {
960  if (snmp_mib_init((void __percpu **)net->mib.udp_stats_in6,
961  sizeof(struct udp_mib),
962  __alignof__(struct udp_mib)) < 0)
963  return -ENOMEM;
964  if (snmp_mib_init((void __percpu **)net->mib.udplite_stats_in6,
965  sizeof(struct udp_mib),
966  __alignof__(struct udp_mib)) < 0)
967  goto err_udplite_mib;
968  if (snmp_mib_init((void __percpu **)net->mib.ipv6_statistics,
969  sizeof(struct ipstats_mib),
970  __alignof__(struct ipstats_mib)) < 0)
971  goto err_ip_mib;
972  if (snmp_mib_init((void __percpu **)net->mib.icmpv6_statistics,
973  sizeof(struct icmpv6_mib),
974  __alignof__(struct icmpv6_mib)) < 0)
975  goto err_icmp_mib;
976  net->mib.icmpv6msg_statistics = kzalloc(sizeof(struct icmpv6msg_mib),
977  GFP_KERNEL);
978  if (!net->mib.icmpv6msg_statistics)
979  goto err_icmpmsg_mib;
980  return 0;
981 
982 err_icmpmsg_mib:
983  snmp_mib_free((void __percpu **)net->mib.icmpv6_statistics);
984 err_icmp_mib:
985  snmp_mib_free((void __percpu **)net->mib.ipv6_statistics);
986 err_ip_mib:
987  snmp_mib_free((void __percpu **)net->mib.udplite_stats_in6);
988 err_udplite_mib:
989  snmp_mib_free((void __percpu **)net->mib.udp_stats_in6);
990  return -ENOMEM;
991 }
992 
993 static void ipv6_cleanup_mibs(struct net *net)
994 {
995  snmp_mib_free((void __percpu **)net->mib.udp_stats_in6);
996  snmp_mib_free((void __percpu **)net->mib.udplite_stats_in6);
997  snmp_mib_free((void __percpu **)net->mib.ipv6_statistics);
998  snmp_mib_free((void __percpu **)net->mib.icmpv6_statistics);
999  kfree(net->mib.icmpv6msg_statistics);
1000 }
1001 
1002 static int __net_init inet6_net_init(struct net *net)
1003 {
1004  int err = 0;
1005 
1006  net->ipv6.sysctl.bindv6only = 0;
1007  net->ipv6.sysctl.icmpv6_time = 1*HZ;
1008 
1009  err = ipv6_init_mibs(net);
1010  if (err)
1011  return err;
1012 #ifdef CONFIG_PROC_FS
1013  err = udp6_proc_init(net);
1014  if (err)
1015  goto out;
1016  err = tcp6_proc_init(net);
1017  if (err)
1018  goto proc_tcp6_fail;
1019  err = ac6_proc_init(net);
1020  if (err)
1021  goto proc_ac6_fail;
1022 #endif
1023  return err;
1024 
1025 #ifdef CONFIG_PROC_FS
1026 proc_ac6_fail:
1027  tcp6_proc_exit(net);
1028 proc_tcp6_fail:
1029  udp6_proc_exit(net);
1030 out:
1031  ipv6_cleanup_mibs(net);
1032  return err;
1033 #endif
1034 }
1035 
1036 static void __net_exit inet6_net_exit(struct net *net)
1037 {
1038 #ifdef CONFIG_PROC_FS
1039  udp6_proc_exit(net);
1040  tcp6_proc_exit(net);
1041  ac6_proc_exit(net);
1042 #endif
1043  ipv6_cleanup_mibs(net);
1044 }
1045 
1046 static struct pernet_operations inet6_net_ops = {
1047  .init = inet6_net_init,
1048  .exit = inet6_net_exit,
1049 };
1050 
1051 static int __init inet6_init(void)
1052 {
1053  struct sk_buff *dummy_skb;
1054  struct list_head *r;
1055  int err = 0;
1056 
1057  BUILD_BUG_ON(sizeof(struct inet6_skb_parm) > sizeof(dummy_skb->cb));
1058 
1059  /* Register the socket-side information for inet6_create. */
1060  for (r = &inetsw6[0]; r < &inetsw6[SOCK_MAX]; ++r)
1061  INIT_LIST_HEAD(r);
1062 
1063  if (disable_ipv6_mod) {
1064  pr_info("Loaded, but administratively disabled, reboot required to enable\n");
1065  goto out;
1066  }
1067 
1068  err = proto_register(&tcpv6_prot, 1);
1069  if (err)
1070  goto out;
1071 
1072  err = proto_register(&udpv6_prot, 1);
1073  if (err)
1074  goto out_unregister_tcp_proto;
1075 
1076  err = proto_register(&udplitev6_prot, 1);
1077  if (err)
1078  goto out_unregister_udp_proto;
1079 
1080  err = proto_register(&rawv6_prot, 1);
1081  if (err)
1082  goto out_unregister_udplite_proto;
1083 
1084 
1085  /* We MUST register RAW sockets before we create the ICMP6,
1086  * IGMP6, or NDISC control sockets.
1087  */
1088  err = rawv6_init();
1089  if (err)
1090  goto out_unregister_raw_proto;
1091 
1092  /* Register the family here so that the init calls below will
1093  * be able to create sockets. (?? is this dangerous ??)
1094  */
1095  err = sock_register(&inet6_family_ops);
1096  if (err)
1097  goto out_sock_register_fail;
1098 
1099  tcpv6_prot.sysctl_mem = init_net.ipv4.sysctl_tcp_mem;
1100 
1101  /*
1102  * ipngwg API draft makes clear that the correct semantics
1103  * for TCP and UDP is to consider one TCP and UDP instance
1104  * in a host available by both INET and INET6 APIs and
1105  * able to communicate via both network protocols.
1106  */
1107 
1108  err = register_pernet_subsys(&inet6_net_ops);
1109  if (err)
1110  goto register_pernet_fail;
1111  err = icmpv6_init();
1112  if (err)
1113  goto icmp_fail;
1114  err = ip6_mr_init();
1115  if (err)
1116  goto ipmr_fail;
1117  err = ndisc_init();
1118  if (err)
1119  goto ndisc_fail;
1120  err = igmp6_init();
1121  if (err)
1122  goto igmp_fail;
1123  err = ipv6_netfilter_init();
1124  if (err)
1125  goto netfilter_fail;
1126  /* Create /proc/foo6 entries. */
1127 #ifdef CONFIG_PROC_FS
1128  err = -ENOMEM;
1129  if (raw6_proc_init())
1130  goto proc_raw6_fail;
1131  if (udplite6_proc_init())
1132  goto proc_udplite6_fail;
1133  if (ipv6_misc_proc_init())
1134  goto proc_misc6_fail;
1135  if (if6_proc_init())
1136  goto proc_if6_fail;
1137 #endif
1138  err = ip6_route_init();
1139  if (err)
1140  goto ip6_route_fail;
1141  err = ip6_flowlabel_init();
1142  if (err)
1143  goto ip6_flowlabel_fail;
1144  err = addrconf_init();
1145  if (err)
1146  goto addrconf_fail;
1147 
1148  /* Init v6 extension headers. */
1149  err = ipv6_exthdrs_init();
1150  if (err)
1151  goto ipv6_exthdrs_fail;
1152 
1153  err = ipv6_frag_init();
1154  if (err)
1155  goto ipv6_frag_fail;
1156 
1157  /* Init v6 transport protocols. */
1158  err = udpv6_init();
1159  if (err)
1160  goto udpv6_fail;
1161 
1162  err = udplitev6_init();
1163  if (err)
1164  goto udplitev6_fail;
1165 
1166  err = tcpv6_init();
1167  if (err)
1168  goto tcpv6_fail;
1169 
1170  err = ipv6_packet_init();
1171  if (err)
1172  goto ipv6_packet_fail;
1173 
1174 #ifdef CONFIG_SYSCTL
1175  err = ipv6_sysctl_register();
1176  if (err)
1177  goto sysctl_fail;
1178 #endif
1179 out:
1180  return err;
1181 
1182 #ifdef CONFIG_SYSCTL
1183 sysctl_fail:
1184  ipv6_packet_cleanup();
1185 #endif
1186 ipv6_packet_fail:
1187  tcpv6_exit();
1188 tcpv6_fail:
1189  udplitev6_exit();
1190 udplitev6_fail:
1191  udpv6_exit();
1192 udpv6_fail:
1193  ipv6_frag_exit();
1194 ipv6_frag_fail:
1195  ipv6_exthdrs_exit();
1196 ipv6_exthdrs_fail:
1197  addrconf_cleanup();
1198 addrconf_fail:
1199  ip6_flowlabel_cleanup();
1200 ip6_flowlabel_fail:
1201  ip6_route_cleanup();
1202 ip6_route_fail:
1203 #ifdef CONFIG_PROC_FS
1204  if6_proc_exit();
1205 proc_if6_fail:
1206  ipv6_misc_proc_exit();
1207 proc_misc6_fail:
1208  udplite6_proc_exit();
1209 proc_udplite6_fail:
1210  raw6_proc_exit();
1211 proc_raw6_fail:
1212 #endif
1213  ipv6_netfilter_fini();
1214 netfilter_fail:
1215  igmp6_cleanup();
1216 igmp_fail:
1217  ndisc_cleanup();
1218 ndisc_fail:
1219  ip6_mr_cleanup();
1220 ipmr_fail:
1221  icmpv6_cleanup();
1222 icmp_fail:
1223  unregister_pernet_subsys(&inet6_net_ops);
1224 register_pernet_fail:
1225  sock_unregister(PF_INET6);
1226  rtnl_unregister_all(PF_INET6);
1227 out_sock_register_fail:
1228  rawv6_exit();
1229 out_unregister_raw_proto:
1230  proto_unregister(&rawv6_prot);
1231 out_unregister_udplite_proto:
1232  proto_unregister(&udplitev6_prot);
1233 out_unregister_udp_proto:
1234  proto_unregister(&udpv6_prot);
1235 out_unregister_tcp_proto:
1236  proto_unregister(&tcpv6_prot);
1237  goto out;
1238 }
1239 module_init(inet6_init);
1240 
1241 static void __exit inet6_exit(void)
1242 {
1243  if (disable_ipv6_mod)
1244  return;
1245 
1246  /* First of all disallow new sockets creation. */
1247  sock_unregister(PF_INET6);
1248  /* Disallow any further netlink messages */
1249  rtnl_unregister_all(PF_INET6);
1250 
1251  udpv6_exit();
1252  udplitev6_exit();
1253  tcpv6_exit();
1254 
1255  /* Cleanup code parts. */
1256  ipv6_packet_cleanup();
1257  ipv6_frag_exit();
1258  ipv6_exthdrs_exit();
1259  addrconf_cleanup();
1260  ip6_flowlabel_cleanup();
1261  ip6_route_cleanup();
1262 #ifdef CONFIG_PROC_FS
1263 
1264  /* Cleanup code parts. */
1265  if6_proc_exit();
1266  ipv6_misc_proc_exit();
1267  udplite6_proc_exit();
1268  raw6_proc_exit();
1269 #endif
1270  ipv6_netfilter_fini();
1271  igmp6_cleanup();
1272  ndisc_cleanup();
1273  ip6_mr_cleanup();
1274  icmpv6_cleanup();
1275  rawv6_exit();
1276 
1277  unregister_pernet_subsys(&inet6_net_ops);
1278  proto_unregister(&rawv6_prot);
1279  proto_unregister(&udplitev6_prot);
1280  proto_unregister(&udpv6_prot);
1281  proto_unregister(&tcpv6_prot);
1282 
1283  rcu_barrier(); /* Wait for completion of call_rcu()'s */
1284 }
1285 module_exit(inet6_exit);
1286 
1287 MODULE_ALIAS_NETPROTO(PF_INET6);
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