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
  64 #include <asm/uaccess.h>
  65 #include <linux/mroute6.h>
  66
  67 MODULE_AUTHOR("Cast of dozens");
  68 MODULE_DESCRIPTION("IPv6 protocol stack for Linux");
  69 MODULE_LICENSE("GPL");
  70
  71 /* The inetsw6 table contains everything that inet6_create needs to
  72  * build a new socket.
  73  */
  74 static struct list_head inetsw6[SOCK_MAX];
  75 static DEFINE_SPINLOCK(inetsw6_lock);
  76
  77 struct ipv6_params ipv6_defaults = {
  78         .disable_ipv6 = 0,
  79         .autoconf = 1,
  80 };
  81
  82 static int disable_ipv6_mod;
  83
  84 module_param_named(disable, disable_ipv6_mod, int, 0444);
  85 MODULE_PARM_DESC(disable, "Disable IPv6 module such that it is non-functional");
  86
  87 module_param_named(disable_ipv6, ipv6_defaults.disable_ipv6, int, 0444);
  88 MODULE_PARM_DESC(disable_ipv6, "Disable IPv6 on all interfaces");
  89
  90 module_param_named(autoconf, ipv6_defaults.autoconf, int, 0444);
  91 MODULE_PARM_DESC(autoconf, "Enable IPv6 address autoconfiguration on all interfaces");
  92
  93 static __inline__ struct ipv6_pinfo *inet6_sk_generic(struct sock *sk)
  94 {
  95         const int offset = sk->sk_prot->obj_size - sizeof(struct ipv6_pinfo);
  96
  97         return (struct ipv6_pinfo *)(((u8 *)sk) + offset);
  98 }
  99
 100 static int inet6_create(struct net *net, struct socket *sock, int protocol,
 101                         int kern)
 102 {
 103         struct inet_sock *inet;
 104         struct ipv6_pinfo *np;
 105         struct sock *sk;
 106         struct inet_protosw *answer;
 107         struct proto *answer_prot;
 108         unsigned char answer_flags;
 109         char answer_no_check;
 110         int try_loading_module = 0;
 111         int err;
 112
 113         if (sock->type != SOCK_RAW &&
 114             sock->type != SOCK_DGRAM &&
 115             !inet_ehash_secret)
 116                 build_ehash_secret();
 117
 118         /* Look for the requested type/protocol pair. */
 119 lookup_protocol:
 120         err = -ESOCKTNOSUPPORT;
 121         rcu_read_lock();
 122         list_for_each_entry_rcu(answer, &inetsw6[sock->type], list) {
 123
 124                 err = 0;
 125                 /* Check the non-wild match. */
 126                 if (protocol == answer->protocol) {
 127                         if (protocol != IPPROTO_IP)
 128                                 break;
 129                 } else {
 130                         /* Check for the two wild cases. */
 131                         if (IPPROTO_IP == protocol) {
 132                                 protocol = answer->protocol;
 133                                 break;
 134                         }
 135                         if (IPPROTO_IP == answer->protocol)
 136                                 break;
 137                 }
 138                 err = -EPROTONOSUPPORT;
 139         }
 140
 141         if (err) {
 142                 if (try_loading_module < 2) {
 143                         rcu_read_unlock();
 144                         /*
 145                          * Be more specific, e.g. net-pf-10-proto-132-type-1
 146                          * (net-pf-PF_INET6-proto-IPPROTO_SCTP-type-SOCK_STREAM)
 147                          */
 148                         if (++try_loading_module == 1)
 149                                 request_module("net-pf-%d-proto-%d-type-%d",
 150                                                 PF_INET6, protocol, sock->type);
 151                         /*
 152                          * Fall back to generic, e.g. net-pf-10-proto-132
 153                          * (net-pf-PF_INET6-proto-IPPROTO_SCTP)
 154                          */
 155                         else
 156                                 request_module("net-pf-%d-proto-%d",
 157                                                 PF_INET6, protocol);
 158                         goto lookup_protocol;
 159                 } else
 160                         goto out_rcu_unlock;
 161         }
 162
 163         err = -EPERM;
 164         if (sock->type == SOCK_RAW && !kern &&
 165             !ns_capable(net->user_ns, CAP_NET_RAW))
 166                 goto out_rcu_unlock;
 167
 168         sock->ops = answer->ops;
 169         answer_prot = answer->prot;
 170         answer_no_check = answer->no_check;
 171         answer_flags = answer->flags;
 172         rcu_read_unlock();
 173
 174         WARN_ON(answer_prot->slab == NULL);
 175
 176         err = -ENOBUFS;
 177         sk = sk_alloc(net, PF_INET6, GFP_KERNEL, answer_prot);
 178         if (sk == NULL)
 179                 goto out;
 180
 181         sock_init_data(sock, sk);
 182
 183         err = 0;
 184         sk->sk_no_check = answer_no_check;
 185         if (INET_PROTOSW_REUSE & answer_flags)
 186                 sk->sk_reuse = SK_CAN_REUSE;
 187
 188         inet = inet_sk(sk);
 189         inet->is_icsk = (INET_PROTOSW_ICSK & answer_flags) != 0;
 190
 191         if (SOCK_RAW == sock->type) {
 192                 inet->inet_num = protocol;
 193                 if (IPPROTO_RAW == protocol)
 194                         inet->hdrincl = 1;
 195         }
 196
 197         sk->sk_destruct         = inet_sock_destruct;
 198         sk->sk_family           = PF_INET6;
 199         sk->sk_protocol         = protocol;
 200
 201         sk->sk_backlog_rcv      = answer->prot->backlog_rcv;
 202
 203         inet_sk(sk)->pinet6 = np = inet6_sk_generic(sk);
 204         np->hop_limit   = -1;
 205         np->mcast_hops  = IPV6_DEFAULT_MCASTHOPS;
 206         np->mc_loop     = 1;
 207         np->pmtudisc    = IPV6_PMTUDISC_WANT;
 208         np->ipv6only    = net->ipv6.sysctl.bindv6only;
 209
 210         /* Init the ipv4 part of the socket since we can have sockets
 211          * using v6 API for ipv4.
 212          */
 213         inet->uc_ttl    = -1;
 214
 215         inet->mc_loop   = 1;
 216         inet->mc_ttl    = 1;
 217         inet->mc_index  = 0;
 218         inet->mc_list   = NULL;
 219         inet->rcv_tos   = 0;
 220
 221         if (ipv4_config.no_pmtu_disc)
 222                 inet->pmtudisc = IP_PMTUDISC_DONT;
 223         else
 224                 inet->pmtudisc = IP_PMTUDISC_WANT;
 225         /*
 226          * Increment only the relevant sk_prot->socks debug field, this changes
 227          * the previous behaviour of incrementing both the equivalent to
 228          * answer->prot->socks (inet6_sock_nr) and inet_sock_nr.
 229          *
 230          * This allows better debug granularity as we'll know exactly how many
 231          * UDPv6, TCPv6, etc socks were allocated, not the sum of all IPv6
 232          * transport protocol socks. -acme
 233          */
 234         sk_refcnt_debug_inc(sk);
 235
 236         if (inet->inet_num) {
 237                 /* It assumes that any protocol which allows
 238                  * the user to assign a number at socket
 239                  * creation time automatically shares.
 240                  */
 241                 inet->inet_sport = htons(inet->inet_num);
 242                 sk->sk_prot->hash(sk);
 243         }
 244         if (sk->sk_prot->init) {
 245                 err = sk->sk_prot->init(sk);
 246                 if (err) {
 247                         sk_common_release(sk);
 248                         goto out;
 249                 }
 250         }
 251 out:
 252         return err;
 253 out_rcu_unlock:
 254         rcu_read_unlock();
 255         goto out;
 256 }
 257
 258
 259 /* bind for INET6 API */
 260 int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 261 {
 262         struct sockaddr_in6 *addr = (struct sockaddr_in6 *)uaddr;
 263         struct sock *sk = sock->sk;
 264         struct inet_sock *inet = inet_sk(sk);
 265         struct ipv6_pinfo *np = inet6_sk(sk);
 266         struct net *net = sock_net(sk);
 267         __be32 v4addr = 0;
 268         unsigned short snum;
 269         int addr_type = 0;
 270         int err = 0;
 271
 272         /* If the socket has its own bind function then use it. */
 273         if (sk->sk_prot->bind)
 274                 return sk->sk_prot->bind(sk, uaddr, addr_len);
 275
 276         if (addr_len < SIN6_LEN_RFC2133)
 277                 return -EINVAL;
 278
 279         if (addr->sin6_family != AF_INET6)
 280                 return -EAFNOSUPPORT;
 281
 282         addr_type = ipv6_addr_type(&addr->sin6_addr);
 283         if ((addr_type & IPV6_ADDR_MULTICAST) && sock->type == SOCK_STREAM)
 284                 return -EINVAL;
 285
 286         snum = ntohs(addr->sin6_port);
 287         if (snum && snum < PROT_SOCK && !ns_capable(net->user_ns, CAP_NET_BIND_SERVICE))
 288                 return -EACCES;
 289
 290         lock_sock(sk);
 291
 292         /* Check these errors (active socket, double bind). */
 293         if (sk->sk_state != TCP_CLOSE || inet->inet_num) {
 294                 err = -EINVAL;
 295                 goto out;
 296         }
 297
 298         /* Check if the address belongs to the host. */
 299         if (addr_type == IPV6_ADDR_MAPPED) {
 300                 int chk_addr_ret;
 301
 302                 /* Binding to v4-mapped address on a v6-only socket
 303                  * makes no sense
 304                  */
 305                 if (np->ipv6only) {
 306                         err = -EINVAL;
 307                         goto out;
 308                 }
 309
 310                 /* Reproduce AF_INET checks to make the bindings consistent */
 311                 v4addr = addr->sin6_addr.s6_addr32[3];
 312                 chk_addr_ret = inet_addr_type(net, v4addr);
 313                 if (!sysctl_ip_nonlocal_bind &&
 314                     !(inet->freebind || inet->transparent) &&
 315                     v4addr != htonl(INADDR_ANY) &&
 316                     chk_addr_ret != RTN_LOCAL &&
 317                     chk_addr_ret != RTN_MULTICAST &&
 318                     chk_addr_ret != RTN_BROADCAST) {
 319                         err = -EADDRNOTAVAIL;
 320                         goto out;
 321                 }
 322         } else {
 323                 if (addr_type != IPV6_ADDR_ANY) {
 324                         struct net_device *dev = NULL;
 325
 326                         rcu_read_lock();
 327                         if (__ipv6_addr_needs_scope_id(addr_type)) {
 328                                 if (addr_len >= sizeof(struct sockaddr_in6) &&
 329                                     addr->sin6_scope_id) {
 330                                         /* Override any existing binding, if another one
 331                                          * is supplied by user.
 332                                          */
 333                                         sk->sk_bound_dev_if = addr->sin6_scope_id;
 334                                 }
 335
 336                                 /* Binding to link-local address requires an interface */
 337                                 if (!sk->sk_bound_dev_if) {
 338                                         err = -EINVAL;
 339                                         goto out_unlock;
 340                                 }
 341                                 dev = dev_get_by_index_rcu(net, sk->sk_bound_dev_if);
 342                                 if (!dev) {
 343                                         err = -ENODEV;
 344                                         goto out_unlock;
 345                                 }
 346                         }
 347
 348                         /* ipv4 addr of the socket is invalid.  Only the
 349                          * unspecified and mapped address have a v4 equivalent.
 350                          */
 351                         v4addr = LOOPBACK4_IPV6;
 352                         if (!(addr_type & IPV6_ADDR_MULTICAST)) {
 353                                 if (!(inet->freebind || inet->transparent) &&
 354                                     !ipv6_chk_addr(net, &addr->sin6_addr,
 355                                                    dev, 0)) {
 356                                         err = -EADDRNOTAVAIL;
 357                                         goto out_unlock;
 358                                 }
 359                         }
 360                         rcu_read_unlock();
 361                 }
 362         }
 363
 364         inet->inet_rcv_saddr = v4addr;
 365         inet->inet_saddr = v4addr;
 366
 367         np->rcv_saddr = addr->sin6_addr;
 368
 369         if (!(addr_type & IPV6_ADDR_MULTICAST))
 370                 np->saddr = addr->sin6_addr;
 371
 372         /* Make sure we are allowed to bind here. */
 373         if (sk->sk_prot->get_port(sk, snum)) {
 374                 inet_reset_saddr(sk);
 375                 err = -EADDRINUSE;
 376                 goto out;
 377         }
 378
 379         if (addr_type != IPV6_ADDR_ANY) {
 380                 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
 381                 if (addr_type != IPV6_ADDR_MAPPED)
 382                         np->ipv6only = 1;
 383         }
 384         if (snum)
 385                 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
 386         inet->inet_sport = htons(inet->inet_num);
 387         inet->inet_dport = 0;
 388         inet->inet_daddr = 0;
 389 out:
 390         release_sock(sk);
 391         return err;
 392 out_unlock:
 393         rcu_read_unlock();
 394         goto out;
 395 }
 396 EXPORT_SYMBOL(inet6_bind);
 397
 398 int inet6_release(struct socket *sock)
 399 {
 400         struct sock *sk = sock->sk;
 401
 402         if (sk == NULL)
 403                 return -EINVAL;
 404
 405         /* Free mc lists */
 406         ipv6_sock_mc_close(sk);
 407
 408         /* Free ac lists */
 409         ipv6_sock_ac_close(sk);
 410
 411         return inet_release(sock);
 412 }
 413 EXPORT_SYMBOL(inet6_release);
 414
 415 void inet6_destroy_sock(struct sock *sk)
 416 {
 417         struct ipv6_pinfo *np = inet6_sk(sk);
 418         struct sk_buff *skb;
 419         struct ipv6_txoptions *opt;
 420
 421         /* Release rx options */
 422
 423         skb = xchg(&np->pktoptions, NULL);
 424         if (skb != NULL)
 425                 kfree_skb(skb);
 426
 427         skb = xchg(&np->rxpmtu, NULL);
 428         if (skb != NULL)
 429                 kfree_skb(skb);
 430
 431         /* Free flowlabels */
 432         fl6_free_socklist(sk);
 433
 434         /* Free tx options */
 435
 436         opt = xchg(&np->opt, NULL);
 437         if (opt != NULL)
 438                 sock_kfree_s(sk, opt, opt->tot_len);
 439 }
 440 EXPORT_SYMBOL_GPL(inet6_destroy_sock);
 441
 442 /*
 443  *      This does both peername and sockname.
 444  */
 445
 446 int inet6_getname(struct socket *sock, struct sockaddr *uaddr,
 447                  int *uaddr_len, int peer)
 448 {
 449         struct sockaddr_in6 *sin = (struct sockaddr_in6 *)uaddr;
 450         struct sock *sk = sock->sk;
 451         struct inet_sock *inet = inet_sk(sk);
 452         struct ipv6_pinfo *np = inet6_sk(sk);
 453
 454         sin->sin6_family = AF_INET6;
 455         sin->sin6_flowinfo = 0;
 456         sin->sin6_scope_id = 0;
 457         if (peer) {
 458                 if (!inet->inet_dport)
 459                         return -ENOTCONN;
 460                 if (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
 461                     peer == 1)
 462                         return -ENOTCONN;
 463                 sin->sin6_port = inet->inet_dport;
 464                 sin->sin6_addr = np->daddr;
 465                 if (np->sndflow)
 466                         sin->sin6_flowinfo = np->flow_label;
 467         } else {
 468                 if (ipv6_addr_any(&np->rcv_saddr))
 469                         sin->sin6_addr = np->saddr;
 470                 else
 471                         sin->sin6_addr = np->rcv_saddr;
 472
 473                 sin->sin6_port = inet->inet_sport;
 474         }
 475         sin->sin6_scope_id = ipv6_iface_scope_id(&sin->sin6_addr,
 476                                                  sk->sk_bound_dev_if);
 477         *uaddr_len = sizeof(*sin);
 478         return 0;
 479 }
 480 EXPORT_SYMBOL(inet6_getname);
 481
 482 int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
 483 {
 484         struct sock *sk = sock->sk;
 485         struct net *net = sock_net(sk);
 486
 487         switch (cmd) {
 488         case SIOCGSTAMP:
 489                 return sock_get_timestamp(sk, (struct timeval __user *)arg);
 490
 491         case SIOCGSTAMPNS:
 492                 return sock_get_timestampns(sk, (struct timespec __user *)arg);
 493
 494         case SIOCADDRT:
 495         case SIOCDELRT:
 496
 497                 return ipv6_route_ioctl(net, cmd, (void __user *)arg);
 498
 499         case SIOCSIFADDR:
 500                 return addrconf_add_ifaddr(net, (void __user *) arg);
 501         case SIOCDIFADDR:
 502                 return addrconf_del_ifaddr(net, (void __user *) arg);
 503         case SIOCSIFDSTADDR:
 504                 return addrconf_set_dstaddr(net, (void __user *) arg);
 505         default:
 506                 if (!sk->sk_prot->ioctl)
 507                         return -ENOIOCTLCMD;
 508                 return sk->sk_prot->ioctl(sk, cmd, arg);
 509         }
 510         /*NOTREACHED*/
 511         return 0;
 512 }
 513 EXPORT_SYMBOL(inet6_ioctl);
 514
 515 const 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
 541 const 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
 566 static const struct net_proto_family inet6_family_ops = {
 567         .family = PF_INET6,
 568         .create = inet6_create,
 569         .owner  = THIS_MODULE,
 570 };
 571
 572 int 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;
 613 out:
 614         spin_unlock_bh(&inetsw6_lock);
 615         return ret;
 616
 617 out_permanent:
 618         pr_err("Attempt to override permanent protocol %d\n", protocol);
 619         goto out;
 620
 621 out_illegal:
 622         pr_err("Ignoring attempt to register invalid socket type %d\n",
 623                p->type);
 624         goto out;
 625 }
 626 EXPORT_SYMBOL(inet6_register_protosw);
 627
 628 void
 629 inet6_unregister_protosw(struct inet_protosw *p)
 630 {
 631         if (INET_PROTOSW_PERMANENT & p->flags) {
 632                 pr_err("Attempt to unregister permanent protocol %d\n",
 633                        p->protocol);
 634         } else {
 635                 spin_lock_bh(&inetsw6_lock);
 636                 list_del_rcu(&p->list);
 637                 spin_unlock_bh(&inetsw6_lock);
 638
 639                 synchronize_net();
 640         }
 641 }
 642 EXPORT_SYMBOL(inet6_unregister_protosw);
 643
 644 int inet6_sk_rebuild_header(struct sock *sk)
 645 {
 646         struct ipv6_pinfo *np = inet6_sk(sk);
 647         struct dst_entry *dst;
 648
 649         dst = __sk_dst_check(sk, np->dst_cookie);
 650
 651         if (dst == NULL) {
 652                 struct inet_sock *inet = inet_sk(sk);
 653                 struct in6_addr *final_p, final;
 654                 struct flowi6 fl6;
 655
 656                 memset(&fl6, 0, sizeof(fl6));
 657                 fl6.flowi6_proto = sk->sk_protocol;
 658                 fl6.daddr = np->daddr;
 659                 fl6.saddr = np->saddr;
 660                 fl6.flowlabel = np->flow_label;
 661                 fl6.flowi6_oif = sk->sk_bound_dev_if;
 662                 fl6.flowi6_mark = sk->sk_mark;
 663                 fl6.fl6_dport = inet->inet_dport;
 664                 fl6.fl6_sport = inet->inet_sport;
 665                 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
 666
 667                 final_p = fl6_update_dst(&fl6, np->opt, &final);
 668
 669                 dst = ip6_dst_lookup_flow(sk, &fl6, final_p, false);
 670                 if (IS_ERR(dst)) {
 671                         sk->sk_route_caps = 0;
 672                         sk->sk_err_soft = -PTR_ERR(dst);
 673                         return PTR_ERR(dst);
 674                 }
 675
 676                 __ip6_dst_store(sk, dst, NULL, NULL);
 677         }
 678
 679         return 0;
 680 }
 681 EXPORT_SYMBOL_GPL(inet6_sk_rebuild_header);
 682
 683 bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb)
 684 {
 685         const struct ipv6_pinfo *np = inet6_sk(sk);
 686         const struct inet6_skb_parm *opt = IP6CB(skb);
 687
 688         if (np->rxopt.all) {
 689                 if ((opt->hop && (np->rxopt.bits.hopopts ||
 690                                   np->rxopt.bits.ohopopts)) ||
 691                     ((IPV6_FLOWINFO_MASK &
 692                       *(__be32 *)skb_network_header(skb)) &&
 693                      np->rxopt.bits.rxflow) ||
 694                     (opt->srcrt && (np->rxopt.bits.srcrt ||
 695                      np->rxopt.bits.osrcrt)) ||
 696                     ((opt->dst1 || opt->dst0) &&
 697                      (np->rxopt.bits.dstopts || np->rxopt.bits.odstopts)))
 698                         return true;
 699         }
 700         return false;
 701 }
 702 EXPORT_SYMBOL_GPL(ipv6_opt_accepted);
 703
 704 static struct packet_type ipv6_packet_type __read_mostly = {
 705         .type = cpu_to_be16(ETH_P_IPV6),
 706         .func = ipv6_rcv,
 707 };
 708
 709 static int __init ipv6_packet_init(void)
 710 {
 711         dev_add_pack(&ipv6_packet_type);
 712         return 0;
 713 }
 714
 715 static void ipv6_packet_cleanup(void)
 716 {
 717         dev_remove_pack(&ipv6_packet_type);
 718 }
 719
 720 static int __net_init ipv6_init_mibs(struct net *net)
 721 {
 722         if (snmp_mib_init((void __percpu **)net->mib.udp_stats_in6,
 723                           sizeof(struct udp_mib),
 724                           __alignof__(struct udp_mib)) < 0)
 725                 return -ENOMEM;
 726         if (snmp_mib_init((void __percpu **)net->mib.udplite_stats_in6,
 727                           sizeof(struct udp_mib),
 728                           __alignof__(struct udp_mib)) < 0)
 729                 goto err_udplite_mib;
 730         if (snmp_mib_init((void __percpu **)net->mib.ipv6_statistics,
 731                           sizeof(struct ipstats_mib),
 732                           __alignof__(struct ipstats_mib)) < 0)
 733                 goto err_ip_mib;
 734         if (snmp_mib_init((void __percpu **)net->mib.icmpv6_statistics,
 735                           sizeof(struct icmpv6_mib),
 736                           __alignof__(struct icmpv6_mib)) < 0)
 737                 goto err_icmp_mib;
 738         net->mib.icmpv6msg_statistics = kzalloc(sizeof(struct icmpv6msg_mib),
 739                                                 GFP_KERNEL);
 740         if (!net->mib.icmpv6msg_statistics)
 741                 goto err_icmpmsg_mib;
 742         return 0;
 743
 744 err_icmpmsg_mib:
 745         snmp_mib_free((void __percpu **)net->mib.icmpv6_statistics);
 746 err_icmp_mib:
 747         snmp_mib_free((void __percpu **)net->mib.ipv6_statistics);
 748 err_ip_mib:
 749         snmp_mib_free((void __percpu **)net->mib.udplite_stats_in6);
 750 err_udplite_mib:
 751         snmp_mib_free((void __percpu **)net->mib.udp_stats_in6);
 752         return -ENOMEM;
 753 }
 754
 755 static void ipv6_cleanup_mibs(struct net *net)
 756 {
 757         snmp_mib_free((void __percpu **)net->mib.udp_stats_in6);
 758         snmp_mib_free((void __percpu **)net->mib.udplite_stats_in6);
 759         snmp_mib_free((void __percpu **)net->mib.ipv6_statistics);
 760         snmp_mib_free((void __percpu **)net->mib.icmpv6_statistics);
 761         kfree(net->mib.icmpv6msg_statistics);
 762 }
 763
 764 static int __net_init inet6_net_init(struct net *net)
 765 {
 766         int err = 0;
 767
 768         net->ipv6.sysctl.bindv6only = 0;
 769         net->ipv6.sysctl.icmpv6_time = 1*HZ;
 770         atomic_set(&net->ipv6.rt_genid, 0);
 771
 772         err = ipv6_init_mibs(net);
 773         if (err)
 774                 return err;
 775 #ifdef CONFIG_PROC_FS
 776         err = udp6_proc_init(net);
 777         if (err)
 778                 goto out;
 779         err = tcp6_proc_init(net);
 780         if (err)
 781                 goto proc_tcp6_fail;
 782         err = ac6_proc_init(net);
 783         if (err)
 784                 goto proc_ac6_fail;
 785 #endif
 786         return err;
 787
 788 #ifdef CONFIG_PROC_FS
 789 proc_ac6_fail:
 790         tcp6_proc_exit(net);
 791 proc_tcp6_fail:
 792         udp6_proc_exit(net);
 793 out:
 794         ipv6_cleanup_mibs(net);
 795         return err;
 796 #endif
 797 }
 798
 799 static void __net_exit inet6_net_exit(struct net *net)
 800 {
 801 #ifdef CONFIG_PROC_FS
 802         udp6_proc_exit(net);
 803         tcp6_proc_exit(net);
 804         ac6_proc_exit(net);
 805 #endif
 806         ipv6_cleanup_mibs(net);
 807 }
 808
 809 static struct pernet_operations inet6_net_ops = {
 810         .init = inet6_net_init,
 811         .exit = inet6_net_exit,
 812 };
 813
 814 static const struct ipv6_stub ipv6_stub_impl = {
 815         .ipv6_sock_mc_join = ipv6_sock_mc_join,
 816         .ipv6_sock_mc_drop = ipv6_sock_mc_drop,
 817         .ipv6_dst_lookup = ip6_dst_lookup,
 818         .udpv6_encap_enable = udpv6_encap_enable,
 819         .ndisc_send_na = ndisc_send_na,
 820         .nd_tbl = &nd_tbl,
 821 };
 822
 823 static int __init inet6_init(void)
 824 {
 825         struct list_head *r;
 826         int err = 0;
 827
 828         BUILD_BUG_ON(sizeof(struct inet6_skb_parm) > FIELD_SIZEOF(struct sk_buff, cb));
 829
 830         /* Register the socket-side information for inet6_create.  */
 831         for (r = &inetsw6[0]; r < &inetsw6[SOCK_MAX]; ++r)
 832                 INIT_LIST_HEAD(r);
 833
 834         if (disable_ipv6_mod) {
 835                 pr_info("Loaded, but administratively disabled, reboot required to enable\n");
 836                 goto out;
 837         }
 838
 839         err = proto_register(&tcpv6_prot, 1);
 840         if (err)
 841                 goto out;
 842
 843         err = proto_register(&udpv6_prot, 1);
 844         if (err)
 845                 goto out_unregister_tcp_proto;
 846
 847         err = proto_register(&udplitev6_prot, 1);
 848         if (err)
 849                 goto out_unregister_udp_proto;
 850
 851         err = proto_register(&rawv6_prot, 1);
 852         if (err)
 853                 goto out_unregister_udplite_proto;
 854
 855         err = proto_register(&pingv6_prot, 1);
 856         if (err)
 857                 goto out_unregister_ping_proto;
 858
 859         /* We MUST register RAW sockets before we create the ICMP6,
 860          * IGMP6, or NDISC control sockets.
 861          */
 862         err = rawv6_init();
 863         if (err)
 864                 goto out_unregister_raw_proto;
 865
 866         /* Register the family here so that the init calls below will
 867          * be able to create sockets. (?? is this dangerous ??)
 868          */
 869         err = sock_register(&inet6_family_ops);
 870         if (err)
 871                 goto out_sock_register_fail;
 872
 873         tcpv6_prot.sysctl_mem = init_net.ipv4.sysctl_tcp_mem;
 874
 875         /*
 876          *      ipngwg API draft makes clear that the correct semantics
 877          *      for TCP and UDP is to consider one TCP and UDP instance
 878          *      in a host available by both INET and INET6 APIs and
 879          *      able to communicate via both network protocols.
 880          */
 881
 882         err = register_pernet_subsys(&inet6_net_ops);
 883         if (err)
 884                 goto register_pernet_fail;
 885         err = icmpv6_init();
 886         if (err)
 887                 goto icmp_fail;
 888         err = ip6_mr_init();
 889         if (err)
 890                 goto ipmr_fail;
 891         err = ndisc_init();
 892         if (err)
 893                 goto ndisc_fail;
 894         err = igmp6_init();
 895         if (err)
 896                 goto igmp_fail;
 897
 898         ipv6_stub = &ipv6_stub_impl;
 899
 900         err = ipv6_netfilter_init();
 901         if (err)
 902                 goto netfilter_fail;
 903         /* Create /proc/foo6 entries. */
 904 #ifdef CONFIG_PROC_FS
 905         err = -ENOMEM;
 906         if (raw6_proc_init())
 907                 goto proc_raw6_fail;
 908         if (udplite6_proc_init())
 909                 goto proc_udplite6_fail;
 910         if (ipv6_misc_proc_init())
 911                 goto proc_misc6_fail;
 912         if (if6_proc_init())
 913                 goto proc_if6_fail;
 914 #endif
 915         err = ip6_route_init();
 916         if (err)
 917                 goto ip6_route_fail;
 918         err = ndisc_late_init();
 919         if (err)
 920                 goto ndisc_late_fail;
 921         err = ip6_flowlabel_init();
 922         if (err)
 923                 goto ip6_flowlabel_fail;
 924         err = addrconf_init();
 925         if (err)
 926                 goto addrconf_fail;
 927
 928         /* Init v6 extension headers. */
 929         err = ipv6_exthdrs_init();
 930         if (err)
 931                 goto ipv6_exthdrs_fail;
 932
 933         err = ipv6_frag_init();
 934         if (err)
 935                 goto ipv6_frag_fail;
 936
 937         /* Init v6 transport protocols. */
 938         err = udpv6_init();
 939         if (err)
 940                 goto udpv6_fail;
 941
 942         err = udplitev6_init();
 943         if (err)
 944                 goto udplitev6_fail;
 945
 946         err = tcpv6_init();
 947         if (err)
 948                 goto tcpv6_fail;
 949
 950         err = ipv6_packet_init();
 951         if (err)
 952                 goto ipv6_packet_fail;
 953
 954         err = pingv6_init();
 955         if (err)
 956                 goto pingv6_fail;
 957
 958 #ifdef CONFIG_SYSCTL
 959         err = ipv6_sysctl_register();
 960         if (err)
 961                 goto sysctl_fail;
 962 #endif
 963 out:
 964         return err;
 965
 966 #ifdef CONFIG_SYSCTL
 967 sysctl_fail:
 968         ipv6_packet_cleanup();
 969 #endif
 970 pingv6_fail:
 971         pingv6_exit();
 972 ipv6_packet_fail:
 973         tcpv6_exit();
 974 tcpv6_fail:
 975         udplitev6_exit();
 976 udplitev6_fail:
 977         udpv6_exit();
 978 udpv6_fail:
 979         ipv6_frag_exit();
 980 ipv6_frag_fail:
 981         ipv6_exthdrs_exit();
 982 ipv6_exthdrs_fail:
 983         addrconf_cleanup();
 984 addrconf_fail:
 985         ip6_flowlabel_cleanup();
 986 ip6_flowlabel_fail:
 987         ndisc_late_cleanup();
 988 ndisc_late_fail:
 989         ip6_route_cleanup();
 990 ip6_route_fail:
 991 #ifdef CONFIG_PROC_FS
 992         if6_proc_exit();
 993 proc_if6_fail:
 994         ipv6_misc_proc_exit();
 995 proc_misc6_fail:
 996         udplite6_proc_exit();
 997 proc_udplite6_fail:
 998         raw6_proc_exit();
 999 proc_raw6_fail:
1000 #endif
1001         ipv6_netfilter_fini();
1002 netfilter_fail:
1003         igmp6_cleanup();
1004 igmp_fail:
1005         ndisc_cleanup();
1006 ndisc_fail:
1007         ip6_mr_cleanup();
1008 ipmr_fail:
1009         icmpv6_cleanup();
1010 icmp_fail:
1011         unregister_pernet_subsys(&inet6_net_ops);
1012 register_pernet_fail:
1013         sock_unregister(PF_INET6);
1014         rtnl_unregister_all(PF_INET6);
1015 out_sock_register_fail:
1016         rawv6_exit();
1017 out_unregister_ping_proto:
1018         proto_unregister(&pingv6_prot);
1019 out_unregister_raw_proto:
1020         proto_unregister(&rawv6_prot);
1021 out_unregister_udplite_proto:
1022         proto_unregister(&udplitev6_prot);
1023 out_unregister_udp_proto:
1024         proto_unregister(&udpv6_prot);
1025 out_unregister_tcp_proto:
1026         proto_unregister(&tcpv6_prot);
1027         goto out;
1028 }
1029 module_init(inet6_init);
1030
1031 static void __exit inet6_exit(void)
1032 {
1033         if (disable_ipv6_mod)
1034                 return;
1035
1036         /* First of all disallow new sockets creation. */
1037         sock_unregister(PF_INET6);
1038         /* Disallow any further netlink messages */
1039         rtnl_unregister_all(PF_INET6);
1040
1041         udpv6_exit();
1042         udplitev6_exit();
1043         tcpv6_exit();
1044
1045         /* Cleanup code parts. */
1046         ipv6_packet_cleanup();
1047         ipv6_frag_exit();
1048         ipv6_exthdrs_exit();
1049         addrconf_cleanup();
1050         ip6_flowlabel_cleanup();
1051         ndisc_late_cleanup();
1052         ip6_route_cleanup();
1053 #ifdef CONFIG_PROC_FS
1054
1055         /* Cleanup code parts. */
1056         if6_proc_exit();
1057         ipv6_misc_proc_exit();
1058         udplite6_proc_exit();
1059         raw6_proc_exit();
1060 #endif
1061         ipv6_netfilter_fini();
1062         ipv6_stub = NULL;
1063         igmp6_cleanup();
1064         ndisc_cleanup();
1065         ip6_mr_cleanup();
1066         icmpv6_cleanup();
1067         rawv6_exit();
1068
1069         unregister_pernet_subsys(&inet6_net_ops);
1070         proto_unregister(&rawv6_prot);
1071         proto_unregister(&udplitev6_prot);
1072         proto_unregister(&udpv6_prot);
1073         proto_unregister(&tcpv6_prot);
1074
1075         rcu_barrier(); /* Wait for completion of call_rcu()'s */
1076 }
1077 module_exit(inet6_exit);
1078
1079 MODULE_ALIAS_NETPROTO(PF_INET6);