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 #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 &&
 164             !ns_capable(net->user_ns, CAP_NET_RAW))
 165                 goto out_rcu_unlock;
 166
 167         sock->ops = answer->ops;
 168         answer_prot = answer->prot;
 169         answer_no_check = answer->no_check;
 170         answer_flags = answer->flags;
 171         rcu_read_unlock();
 172
 173         WARN_ON(answer_prot->slab == NULL);
 174
 175         err = -ENOBUFS;
 176         sk = sk_alloc(net, PF_INET6, GFP_KERNEL, answer_prot);
 177         if (sk == NULL)
 178                 goto out;
 179
 180         sock_init_data(sock, sk);
 181
 182         err = 0;
 183         sk->sk_no_check = answer_no_check;
 184         if (INET_PROTOSW_REUSE & answer_flags)
 185                 sk->sk_reuse = SK_CAN_REUSE;
 186
 187         inet = inet_sk(sk);
 188         inet->is_icsk = (INET_PROTOSW_ICSK & answer_flags) != 0;
 189
 190         if (SOCK_RAW == sock->type) {
 191                 inet->inet_num = protocol;
 192                 if (IPPROTO_RAW == protocol)
 193                         inet->hdrincl = 1;
 194         }
 195
 196         sk->sk_destruct         = inet_sock_destruct;
 197         sk->sk_family           = PF_INET6;
 198         sk->sk_protocol         = protocol;
 199
 200         sk->sk_backlog_rcv      = answer->prot->backlog_rcv;
 201
 202         inet_sk(sk)->pinet6 = np = inet6_sk_generic(sk);
 203         np->hop_limit   = -1;
 204         np->mcast_hops  = IPV6_DEFAULT_MCASTHOPS;
 205         np->mc_loop     = 1;
 206         np->pmtudisc    = IPV6_PMTUDISC_WANT;
 207         np->ipv6only    = net->ipv6.sysctl.bindv6only;
 208
 209         /* Init the ipv4 part of the socket since we can have sockets
 210          * using v6 API for ipv4.
 211          */
 212         inet->uc_ttl    = -1;
 213
 214         inet->mc_loop   = 1;
 215         inet->mc_ttl    = 1;
 216         inet->mc_index  = 0;
 217         inet->mc_list   = NULL;
 218         inet->rcv_tos   = 0;
 219
 220         if (ipv4_config.no_pmtu_disc)
 221                 inet->pmtudisc = IP_PMTUDISC_DONT;
 222         else
 223                 inet->pmtudisc = IP_PMTUDISC_WANT;
 224         /*
 225          * Increment only the relevant sk_prot->socks debug field, this changes
 226          * the previous behaviour of incrementing both the equivalent to
 227          * answer->prot->socks (inet6_sock_nr) and inet_sock_nr.
 228          *
 229          * This allows better debug granularity as we'll know exactly how many
 230          * UDPv6, TCPv6, etc socks were allocated, not the sum of all IPv6
 231          * transport protocol socks. -acme
 232          */
 233         sk_refcnt_debug_inc(sk);
 234
 235         if (inet->inet_num) {
 236                 /* It assumes that any protocol which allows
 237                  * the user to assign a number at socket
 238                  * creation time automatically shares.
 239                  */
 240                 inet->inet_sport = htons(inet->inet_num);
 241                 sk->sk_prot->hash(sk);
 242         }
 243         if (sk->sk_prot->init) {
 244                 err = sk->sk_prot->init(sk);
 245                 if (err) {
 246                         sk_common_release(sk);
 247                         goto out;
 248                 }
 249         }
 250 out:
 251         return err;
 252 out_rcu_unlock:
 253         rcu_read_unlock();
 254         goto out;
 255 }
 256
 257
 258 /* bind for INET6 API */
 259 int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 260 {
 261         struct sockaddr_in6 *addr = (struct sockaddr_in6 *)uaddr;
 262         struct sock *sk = sock->sk;
 263         struct inet_sock *inet = inet_sk(sk);
 264         struct ipv6_pinfo *np = inet6_sk(sk);
 265         struct net *net = sock_net(sk);
 266         __be32 v4addr = 0;
 267         unsigned short snum;
 268         int addr_type = 0;
 269         int err = 0;
 270
 271         /* If the socket has its own bind function then use it. */
 272         if (sk->sk_prot->bind)
 273                 return sk->sk_prot->bind(sk, uaddr, addr_len);
 274
 275         if (addr_len < SIN6_LEN_RFC2133)
 276                 return -EINVAL;
 277
 278         if (addr->sin6_family != AF_INET6)
 279                 return -EAFNOSUPPORT;
 280
 281         addr_type = ipv6_addr_type(&addr->sin6_addr);
 282         if ((addr_type & IPV6_ADDR_MULTICAST) && sock->type == SOCK_STREAM)
 283                 return -EINVAL;
 284
 285         snum = ntohs(addr->sin6_port);
 286         if (snum && snum < PROT_SOCK && !ns_capable(net->user_ns, CAP_NET_BIND_SERVICE))
 287                 return -EACCES;
 288
 289         lock_sock(sk);
 290
 291         /* Check these errors (active socket, double bind). */
 292         if (sk->sk_state != TCP_CLOSE || inet->inet_num) {
 293                 err = -EINVAL;
 294                 goto out;
 295         }
 296
 297         /* Check if the address belongs to the host. */
 298         if (addr_type == IPV6_ADDR_MAPPED) {
 299                 int chk_addr_ret;
 300
 301                 /* Binding to v4-mapped address on a v6-only socket
 302                  * makes no sense
 303                  */
 304                 if (np->ipv6only) {
 305                         err = -EINVAL;
 306                         goto out;
 307                 }
 308
 309                 /* Reproduce AF_INET checks to make the bindings consistent */
 310                 v4addr = addr->sin6_addr.s6_addr32[3];
 311                 chk_addr_ret = inet_addr_type(net, v4addr);
 312                 if (!sysctl_ip_nonlocal_bind &&
 313                     !(inet->freebind || inet->transparent) &&
 314                     v4addr != htonl(INADDR_ANY) &&
 315                     chk_addr_ret != RTN_LOCAL &&
 316                     chk_addr_ret != RTN_MULTICAST &&
 317                     chk_addr_ret != RTN_BROADCAST) {
 318                         err = -EADDRNOTAVAIL;
 319                         goto out;
 320                 }
 321         } else {
 322                 if (addr_type != IPV6_ADDR_ANY) {
 323                         struct net_device *dev = NULL;
 324
 325                         rcu_read_lock();
 326                         if (__ipv6_addr_needs_scope_id(addr_type)) {
 327                                 if (addr_len >= sizeof(struct sockaddr_in6) &&
 328                                     addr->sin6_scope_id) {
 329                                         /* Override any existing binding, if another one
 330                                          * is supplied by user.
 331                                          */
 332                                         sk->sk_bound_dev_if = addr->sin6_scope_id;
 333                                 }
 334
 335                                 /* Binding to link-local address requires an interface */
 336                                 if (!sk->sk_bound_dev_if) {
 337                                         err = -EINVAL;
 338                                         goto out_unlock;
 339                                 }
 340                                 dev = dev_get_by_index_rcu(net, sk->sk_bound_dev_if);
 341                                 if (!dev) {
 342                                         err = -ENODEV;
 343                                         goto out_unlock;
 344                                 }
 345                         }
 346
 347                         /* ipv4 addr of the socket is invalid.  Only the
 348                          * unspecified and mapped address have a v4 equivalent.
 349                          */
 350                         v4addr = LOOPBACK4_IPV6;
 351                         if (!(addr_type & IPV6_ADDR_MULTICAST)) {
 352                                 if (!(inet->freebind || inet->transparent) &&
 353                                     !ipv6_chk_addr(net, &addr->sin6_addr,
 354                                                    dev, 0)) {
 355                                         err = -EADDRNOTAVAIL;
 356                                         goto out_unlock;
 357                                 }
 358                         }
 359                         rcu_read_unlock();
 360                 }
 361         }
 362
 363         inet->inet_rcv_saddr = v4addr;
 364         inet->inet_saddr = v4addr;
 365
 366         np->rcv_saddr = addr->sin6_addr;
 367
 368         if (!(addr_type & IPV6_ADDR_MULTICAST))
 369                 np->saddr = addr->sin6_addr;
 370
 371         /* Make sure we are allowed to bind here. */
 372         if (sk->sk_prot->get_port(sk, snum)) {
 373                 inet_reset_saddr(sk);
 374                 err = -EADDRINUSE;
 375                 goto out;
 376         }
 377
 378         if (addr_type != IPV6_ADDR_ANY) {
 379                 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
 380                 if (addr_type != IPV6_ADDR_MAPPED)
 381                         np->ipv6only = 1;
 382         }
 383         if (snum)
 384                 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
 385         inet->inet_sport = htons(inet->inet_num);
 386         inet->inet_dport = 0;
 387         inet->inet_daddr = 0;
 388 out:
 389         release_sock(sk);
 390         return err;
 391 out_unlock:
 392         rcu_read_unlock();
 393         goto out;
 394 }
 395 EXPORT_SYMBOL(inet6_bind);
 396
 397 int inet6_release(struct socket *sock)
 398 {
 399         struct sock *sk = sock->sk;
 400
 401         if (sk == NULL)
 402                 return -EINVAL;
 403
 404         /* Free mc lists */
 405         ipv6_sock_mc_close(sk);
 406
 407         /* Free ac lists */
 408         ipv6_sock_ac_close(sk);
 409
 410         return inet_release(sock);
 411 }
 412 EXPORT_SYMBOL(inet6_release);
 413
 414 void inet6_destroy_sock(struct sock *sk)
 415 {
 416         struct ipv6_pinfo *np = inet6_sk(sk);
 417         struct sk_buff *skb;
 418         struct ipv6_txoptions *opt;
 419
 420         /* Release rx options */
 421
 422         skb = xchg(&np->pktoptions, NULL);
 423         if (skb != NULL)
 424                 kfree_skb(skb);
 425
 426         skb = xchg(&np->rxpmtu, NULL);
 427         if (skb != NULL)
 428                 kfree_skb(skb);
 429
 430         /* Free flowlabels */
 431         fl6_free_socklist(sk);
 432
 433         /* Free tx options */
 434
 435         opt = xchg(&np->opt, NULL);
 436         if (opt != NULL)
 437                 sock_kfree_s(sk, opt, opt->tot_len);
 438 }
 439 EXPORT_SYMBOL_GPL(inet6_destroy_sock);
 440
 441 /*
 442  *      This does both peername and sockname.
 443  */
 444
 445 int inet6_getname(struct socket *sock, struct sockaddr *uaddr,
 446                  int *uaddr_len, int peer)
 447 {
 448         struct sockaddr_in6 *sin = (struct sockaddr_in6 *)uaddr;
 449         struct sock *sk = sock->sk;
 450         struct inet_sock *inet = inet_sk(sk);
 451         struct ipv6_pinfo *np = inet6_sk(sk);
 452
 453         sin->sin6_family = AF_INET6;
 454         sin->sin6_flowinfo = 0;
 455         sin->sin6_scope_id = 0;
 456         if (peer) {
 457                 if (!inet->inet_dport)
 458                         return -ENOTCONN;
 459                 if (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
 460                     peer == 1)
 461                         return -ENOTCONN;
 462                 sin->sin6_port = inet->inet_dport;
 463                 sin->sin6_addr = np->daddr;
 464                 if (np->sndflow)
 465                         sin->sin6_flowinfo = np->flow_label;
 466         } else {
 467                 if (ipv6_addr_any(&np->rcv_saddr))
 468                         sin->sin6_addr = np->saddr;
 469                 else
 470                         sin->sin6_addr = np->rcv_saddr;
 471
 472                 sin->sin6_port = inet->inet_sport;
 473         }
 474         sin->sin6_scope_id = ipv6_iface_scope_id(&sin->sin6_addr,
 475                                                  sk->sk_bound_dev_if);
 476         *uaddr_len = sizeof(*sin);
 477         return 0;
 478 }
 479 EXPORT_SYMBOL(inet6_getname);
 480
 481 int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
 482 {
 483         struct sock *sk = sock->sk;
 484         struct net *net = sock_net(sk);
 485
 486         switch (cmd) {
 487         case SIOCGSTAMP:
 488                 return sock_get_timestamp(sk, (struct timeval __user *)arg);
 489
 490         case SIOCGSTAMPNS:
 491                 return sock_get_timestampns(sk, (struct timespec __user *)arg);
 492
 493         case SIOCADDRT:
 494         case SIOCDELRT:
 495
 496                 return ipv6_route_ioctl(net, cmd, (void __user *)arg);
 497
 498         case SIOCSIFADDR:
 499                 return addrconf_add_ifaddr(net, (void __user *) arg);
 500         case SIOCDIFADDR:
 501                 return addrconf_del_ifaddr(net, (void __user *) arg);
 502         case SIOCSIFDSTADDR:
 503                 return addrconf_set_dstaddr(net, (void __user *) arg);
 504         default:
 505                 if (!sk->sk_prot->ioctl)
 506                         return -ENOIOCTLCMD;
 507                 return sk->sk_prot->ioctl(sk, cmd, arg);
 508         }
 509         /*NOTREACHED*/
 510         return 0;
 511 }
 512 EXPORT_SYMBOL(inet6_ioctl);
 513
 514 const struct proto_ops inet6_stream_ops = {
 515         .family            = PF_INET6,
 516         .owner             = THIS_MODULE,
 517         .release           = inet6_release,
 518         .bind              = inet6_bind,
 519         .connect           = inet_stream_connect,       /* ok           */
 520         .socketpair        = sock_no_socketpair,        /* a do nothing */
 521         .accept            = inet_accept,               /* ok           */
 522         .getname           = inet6_getname,
 523         .poll              = tcp_poll,                  /* ok           */
 524         .ioctl             = inet6_ioctl,               /* must change  */
 525         .listen            = inet_listen,               /* ok           */
 526         .shutdown          = inet_shutdown,             /* ok           */
 527         .setsockopt        = sock_common_setsockopt,    /* ok           */
 528         .getsockopt        = sock_common_getsockopt,    /* ok           */
 529         .sendmsg           = inet_sendmsg,              /* ok           */
 530         .recvmsg           = inet_recvmsg,              /* ok           */
 531         .mmap              = sock_no_mmap,
 532         .sendpage          = inet_sendpage,
 533         .splice_read       = tcp_splice_read,
 534 #ifdef CONFIG_COMPAT
 535         .compat_setsockopt = compat_sock_common_setsockopt,
 536         .compat_getsockopt = compat_sock_common_getsockopt,
 537 #endif
 538 };
 539
 540 const struct proto_ops inet6_dgram_ops = {
 541         .family            = PF_INET6,
 542         .owner             = THIS_MODULE,
 543         .release           = inet6_release,
 544         .bind              = inet6_bind,
 545         .connect           = inet_dgram_connect,        /* ok           */
 546         .socketpair        = sock_no_socketpair,        /* a do nothing */
 547         .accept            = sock_no_accept,            /* a do nothing */
 548         .getname           = inet6_getname,
 549         .poll              = udp_poll,                  /* ok           */
 550         .ioctl             = inet6_ioctl,               /* must change  */
 551         .listen            = sock_no_listen,            /* ok           */
 552         .shutdown          = inet_shutdown,             /* ok           */
 553         .setsockopt        = sock_common_setsockopt,    /* ok           */
 554         .getsockopt        = sock_common_getsockopt,    /* ok           */
 555         .sendmsg           = inet_sendmsg,              /* ok           */
 556         .recvmsg           = inet_recvmsg,              /* ok           */
 557         .mmap              = sock_no_mmap,
 558         .sendpage          = sock_no_sendpage,
 559 #ifdef CONFIG_COMPAT
 560         .compat_setsockopt = compat_sock_common_setsockopt,
 561         .compat_getsockopt = compat_sock_common_getsockopt,
 562 #endif
 563 };
 564
 565 static const struct net_proto_family inet6_family_ops = {
 566         .family = PF_INET6,
 567         .create = inet6_create,
 568         .owner  = THIS_MODULE,
 569 };
 570
 571 int inet6_register_protosw(struct inet_protosw *p)
 572 {
 573         struct list_head *lh;
 574         struct inet_protosw *answer;
 575         struct list_head *last_perm;
 576         int protocol = p->protocol;
 577         int ret;
 578
 579         spin_lock_bh(&inetsw6_lock);
 580
 581         ret = -EINVAL;
 582         if (p->type >= SOCK_MAX)
 583                 goto out_illegal;
 584
 585         /* If we are trying to override a permanent protocol, bail. */
 586         answer = NULL;
 587         ret = -EPERM;
 588         last_perm = &inetsw6[p->type];
 589         list_for_each(lh, &inetsw6[p->type]) {
 590                 answer = list_entry(lh, struct inet_protosw, list);
 591
 592                 /* Check only the non-wild match. */
 593                 if (INET_PROTOSW_PERMANENT & answer->flags) {
 594                         if (protocol == answer->protocol)
 595                                 break;
 596                         last_perm = lh;
 597                 }
 598
 599                 answer = NULL;
 600         }
 601         if (answer)
 602                 goto out_permanent;
 603
 604         /* Add the new entry after the last permanent entry if any, so that
 605          * the new entry does not override a permanent entry when matched with
 606          * a wild-card protocol. But it is allowed to override any existing
 607          * non-permanent entry.  This means that when we remove this entry, the
 608          * system automatically returns to the old behavior.
 609          */
 610         list_add_rcu(&p->list, last_perm);
 611         ret = 0;
 612 out:
 613         spin_unlock_bh(&inetsw6_lock);
 614         return ret;
 615
 616 out_permanent:
 617         pr_err("Attempt to override permanent protocol %d\n", protocol);
 618         goto out;
 619
 620 out_illegal:
 621         pr_err("Ignoring attempt to register invalid socket type %d\n",
 622                p->type);
 623         goto out;
 624 }
 625 EXPORT_SYMBOL(inet6_register_protosw);
 626
 627 void
 628 inet6_unregister_protosw(struct inet_protosw *p)
 629 {
 630         if (INET_PROTOSW_PERMANENT & p->flags) {
 631                 pr_err("Attempt to unregister permanent protocol %d\n",
 632                        p->protocol);
 633         } else {
 634                 spin_lock_bh(&inetsw6_lock);
 635                 list_del_rcu(&p->list);
 636                 spin_unlock_bh(&inetsw6_lock);
 637
 638                 synchronize_net();
 639         }
 640 }
 641 EXPORT_SYMBOL(inet6_unregister_protosw);
 642
 643 int inet6_sk_rebuild_header(struct sock *sk)
 644 {
 645         struct ipv6_pinfo *np = inet6_sk(sk);
 646         struct dst_entry *dst;
 647
 648         dst = __sk_dst_check(sk, np->dst_cookie);
 649
 650         if (dst == NULL) {
 651                 struct inet_sock *inet = inet_sk(sk);
 652                 struct in6_addr *final_p, final;
 653                 struct flowi6 fl6;
 654
 655                 memset(&fl6, 0, sizeof(fl6));
 656                 fl6.flowi6_proto = sk->sk_protocol;
 657                 fl6.daddr = np->daddr;
 658                 fl6.saddr = np->saddr;
 659                 fl6.flowlabel = np->flow_label;
 660                 fl6.flowi6_oif = sk->sk_bound_dev_if;
 661                 fl6.flowi6_mark = sk->sk_mark;
 662                 fl6.fl6_dport = inet->inet_dport;
 663                 fl6.fl6_sport = inet->inet_sport;
 664                 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
 665
 666                 final_p = fl6_update_dst(&fl6, np->opt, &final);
 667
 668                 dst = ip6_dst_lookup_flow(sk, &fl6, final_p, false);
 669                 if (IS_ERR(dst)) {
 670                         sk->sk_route_caps = 0;
 671                         sk->sk_err_soft = -PTR_ERR(dst);
 672                         return PTR_ERR(dst);
 673                 }
 674
 675                 __ip6_dst_store(sk, dst, NULL, NULL);
 676         }
 677
 678         return 0;
 679 }
 680 EXPORT_SYMBOL_GPL(inet6_sk_rebuild_header);
 681
 682 bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb)
 683 {
 684         const struct ipv6_pinfo *np = inet6_sk(sk);
 685         const struct inet6_skb_parm *opt = IP6CB(skb);
 686
 687         if (np->rxopt.all) {
 688                 if ((opt->hop && (np->rxopt.bits.hopopts ||
 689                                   np->rxopt.bits.ohopopts)) ||
 690                     ((IPV6_FLOWINFO_MASK &
 691                       *(__be32 *)skb_network_header(skb)) &&
 692                      np->rxopt.bits.rxflow) ||
 693                     (opt->srcrt && (np->rxopt.bits.srcrt ||
 694                      np->rxopt.bits.osrcrt)) ||
 695                     ((opt->dst1 || opt->dst0) &&
 696                      (np->rxopt.bits.dstopts || np->rxopt.bits.odstopts)))
 697                         return true;
 698         }
 699         return false;
 700 }
 701 EXPORT_SYMBOL_GPL(ipv6_opt_accepted);
 702
 703 static struct packet_type ipv6_packet_type __read_mostly = {
 704         .type = cpu_to_be16(ETH_P_IPV6),
 705         .func = ipv6_rcv,
 706 };
 707
 708 static int __init ipv6_packet_init(void)
 709 {
 710         dev_add_pack(&ipv6_packet_type);
 711         return 0;
 712 }
 713
 714 static void ipv6_packet_cleanup(void)
 715 {
 716         dev_remove_pack(&ipv6_packet_type);
 717 }
 718
 719 static int __net_init ipv6_init_mibs(struct net *net)
 720 {
 721         if (snmp_mib_init((void __percpu **)net->mib.udp_stats_in6,
 722                           sizeof(struct udp_mib),
 723                           __alignof__(struct udp_mib)) < 0)
 724                 return -ENOMEM;
 725         if (snmp_mib_init((void __percpu **)net->mib.udplite_stats_in6,
 726                           sizeof(struct udp_mib),
 727                           __alignof__(struct udp_mib)) < 0)
 728                 goto err_udplite_mib;
 729         if (snmp_mib_init((void __percpu **)net->mib.ipv6_statistics,
 730                           sizeof(struct ipstats_mib),
 731                           __alignof__(struct ipstats_mib)) < 0)
 732                 goto err_ip_mib;
 733         if (snmp_mib_init((void __percpu **)net->mib.icmpv6_statistics,
 734                           sizeof(struct icmpv6_mib),
 735                           __alignof__(struct icmpv6_mib)) < 0)
 736                 goto err_icmp_mib;
 737         net->mib.icmpv6msg_statistics = kzalloc(sizeof(struct icmpv6msg_mib),
 738                                                 GFP_KERNEL);
 739         if (!net->mib.icmpv6msg_statistics)
 740                 goto err_icmpmsg_mib;
 741         return 0;
 742
 743 err_icmpmsg_mib:
 744         snmp_mib_free((void __percpu **)net->mib.icmpv6_statistics);
 745 err_icmp_mib:
 746         snmp_mib_free((void __percpu **)net->mib.ipv6_statistics);
 747 err_ip_mib:
 748         snmp_mib_free((void __percpu **)net->mib.udplite_stats_in6);
 749 err_udplite_mib:
 750         snmp_mib_free((void __percpu **)net->mib.udp_stats_in6);
 751         return -ENOMEM;
 752 }
 753
 754 static void ipv6_cleanup_mibs(struct net *net)
 755 {
 756         snmp_mib_free((void __percpu **)net->mib.udp_stats_in6);
 757         snmp_mib_free((void __percpu **)net->mib.udplite_stats_in6);
 758         snmp_mib_free((void __percpu **)net->mib.ipv6_statistics);
 759         snmp_mib_free((void __percpu **)net->mib.icmpv6_statistics);
 760         kfree(net->mib.icmpv6msg_statistics);
 761 }
 762
 763 static int __net_init inet6_net_init(struct net *net)
 764 {
 765         int err = 0;
 766
 767         net->ipv6.sysctl.bindv6only = 0;
 768         net->ipv6.sysctl.icmpv6_time = 1*HZ;
 769         atomic_set(&net->ipv6.rt_genid, 0);
 770
 771         err = ipv6_init_mibs(net);
 772         if (err)
 773                 return err;
 774 #ifdef CONFIG_PROC_FS
 775         err = udp6_proc_init(net);
 776         if (err)
 777                 goto out;
 778         err = tcp6_proc_init(net);
 779         if (err)
 780                 goto proc_tcp6_fail;
 781         err = ac6_proc_init(net);
 782         if (err)
 783                 goto proc_ac6_fail;
 784 #endif
 785         return err;
 786
 787 #ifdef CONFIG_PROC_FS
 788 proc_ac6_fail:
 789         tcp6_proc_exit(net);
 790 proc_tcp6_fail:
 791         udp6_proc_exit(net);
 792 out:
 793         ipv6_cleanup_mibs(net);
 794         return err;
 795 #endif
 796 }
 797
 798 static void __net_exit inet6_net_exit(struct net *net)
 799 {
 800 #ifdef CONFIG_PROC_FS
 801         udp6_proc_exit(net);
 802         tcp6_proc_exit(net);
 803         ac6_proc_exit(net);
 804 #endif
 805         ipv6_cleanup_mibs(net);
 806 }
 807
 808 static struct pernet_operations inet6_net_ops = {
 809         .init = inet6_net_init,
 810         .exit = inet6_net_exit,
 811 };
 812
 813 static int __init inet6_init(void)
 814 {
 815         struct list_head *r;
 816         int err = 0;
 817
 818         BUILD_BUG_ON(sizeof(struct inet6_skb_parm) > FIELD_SIZEOF(struct sk_buff, cb));
 819
 820         /* Register the socket-side information for inet6_create.  */
 821         for (r = &inetsw6[0]; r < &inetsw6[SOCK_MAX]; ++r)
 822                 INIT_LIST_HEAD(r);
 823
 824         if (disable_ipv6_mod) {
 825                 pr_info("Loaded, but administratively disabled, reboot required to enable\n");
 826                 goto out;
 827         }
 828
 829         err = proto_register(&tcpv6_prot, 1);
 830         if (err)
 831                 goto out;
 832
 833         err = proto_register(&udpv6_prot, 1);
 834         if (err)
 835                 goto out_unregister_tcp_proto;
 836
 837         err = proto_register(&udplitev6_prot, 1);
 838         if (err)
 839                 goto out_unregister_udp_proto;
 840
 841         err = proto_register(&rawv6_prot, 1);
 842         if (err)
 843                 goto out_unregister_udplite_proto;
 844
 845         err = proto_register(&pingv6_prot, 1);
 846         if (err)
 847                 goto out_unregister_ping_proto;
 848
 849         /* We MUST register RAW sockets before we create the ICMP6,
 850          * IGMP6, or NDISC control sockets.
 851          */
 852         err = rawv6_init();
 853         if (err)
 854                 goto out_unregister_raw_proto;
 855
 856         /* Register the family here so that the init calls below will
 857          * be able to create sockets. (?? is this dangerous ??)
 858          */
 859         err = sock_register(&inet6_family_ops);
 860         if (err)
 861                 goto out_sock_register_fail;
 862
 863         tcpv6_prot.sysctl_mem = init_net.ipv4.sysctl_tcp_mem;
 864
 865         /*
 866          *      ipngwg API draft makes clear that the correct semantics
 867          *      for TCP and UDP is to consider one TCP and UDP instance
 868          *      in a host available by both INET and INET6 APIs and
 869          *      able to communicate via both network protocols.
 870          */
 871
 872         err = register_pernet_subsys(&inet6_net_ops);
 873         if (err)
 874                 goto register_pernet_fail;
 875         err = icmpv6_init();
 876         if (err)
 877                 goto icmp_fail;
 878         err = ip6_mr_init();
 879         if (err)
 880                 goto ipmr_fail;
 881         err = ndisc_init();
 882         if (err)
 883                 goto ndisc_fail;
 884         err = igmp6_init();
 885         if (err)
 886                 goto igmp_fail;
 887         err = ipv6_netfilter_init();
 888         if (err)
 889                 goto netfilter_fail;
 890         /* Create /proc/foo6 entries. */
 891 #ifdef CONFIG_PROC_FS
 892         err = -ENOMEM;
 893         if (raw6_proc_init())
 894                 goto proc_raw6_fail;
 895         if (udplite6_proc_init())
 896                 goto proc_udplite6_fail;
 897         if (ipv6_misc_proc_init())
 898                 goto proc_misc6_fail;
 899         if (if6_proc_init())
 900                 goto proc_if6_fail;
 901 #endif
 902         err = ip6_route_init();
 903         if (err)
 904                 goto ip6_route_fail;
 905         err = ip6_flowlabel_init();
 906         if (err)
 907                 goto ip6_flowlabel_fail;
 908         err = addrconf_init();
 909         if (err)
 910                 goto addrconf_fail;
 911
 912         /* Init v6 extension headers. */
 913         err = ipv6_exthdrs_init();
 914         if (err)
 915                 goto ipv6_exthdrs_fail;
 916
 917         err = ipv6_frag_init();
 918         if (err)
 919                 goto ipv6_frag_fail;
 920
 921         /* Init v6 transport protocols. */
 922         err = udpv6_init();
 923         if (err)
 924                 goto udpv6_fail;
 925
 926         err = udplitev6_init();
 927         if (err)
 928                 goto udplitev6_fail;
 929
 930         err = tcpv6_init();
 931         if (err)
 932                 goto tcpv6_fail;
 933
 934         err = ipv6_packet_init();
 935         if (err)
 936                 goto ipv6_packet_fail;
 937
 938         err = pingv6_init();
 939         if (err)
 940                 goto pingv6_fail;
 941
 942 #ifdef CONFIG_SYSCTL
 943         err = ipv6_sysctl_register();
 944         if (err)
 945                 goto sysctl_fail;
 946 #endif
 947 out:
 948         return err;
 949
 950 #ifdef CONFIG_SYSCTL
 951 sysctl_fail:
 952         ipv6_packet_cleanup();
 953 #endif
 954 pingv6_fail:
 955         pingv6_exit();
 956 ipv6_packet_fail:
 957         tcpv6_exit();
 958 tcpv6_fail:
 959         udplitev6_exit();
 960 udplitev6_fail:
 961         udpv6_exit();
 962 udpv6_fail:
 963         ipv6_frag_exit();
 964 ipv6_frag_fail:
 965         ipv6_exthdrs_exit();
 966 ipv6_exthdrs_fail:
 967         addrconf_cleanup();
 968 addrconf_fail:
 969         ip6_flowlabel_cleanup();
 970 ip6_flowlabel_fail:
 971         ip6_route_cleanup();
 972 ip6_route_fail:
 973 #ifdef CONFIG_PROC_FS
 974         if6_proc_exit();
 975 proc_if6_fail:
 976         ipv6_misc_proc_exit();
 977 proc_misc6_fail:
 978         udplite6_proc_exit();
 979 proc_udplite6_fail:
 980         raw6_proc_exit();
 981 proc_raw6_fail:
 982 #endif
 983         ipv6_netfilter_fini();
 984 netfilter_fail:
 985         igmp6_cleanup();
 986 igmp_fail:
 987         ndisc_cleanup();
 988 ndisc_fail:
 989         ip6_mr_cleanup();
 990 ipmr_fail:
 991         icmpv6_cleanup();
 992 icmp_fail:
 993         unregister_pernet_subsys(&inet6_net_ops);
 994 register_pernet_fail:
 995         sock_unregister(PF_INET6);
 996         rtnl_unregister_all(PF_INET6);
 997 out_sock_register_fail:
 998         rawv6_exit();
 999 out_unregister_ping_proto:
1000         proto_unregister(&pingv6_prot);
1001 out_unregister_raw_proto:
1002         proto_unregister(&rawv6_prot);
1003 out_unregister_udplite_proto:
1004         proto_unregister(&udplitev6_prot);
1005 out_unregister_udp_proto:
1006         proto_unregister(&udpv6_prot);
1007 out_unregister_tcp_proto:
1008         proto_unregister(&tcpv6_prot);
1009         goto out;
1010 }
1011 module_init(inet6_init);
1012
1013 static void __exit inet6_exit(void)
1014 {
1015         if (disable_ipv6_mod)
1016                 return;
1017
1018         /* First of all disallow new sockets creation. */
1019         sock_unregister(PF_INET6);
1020         /* Disallow any further netlink messages */
1021         rtnl_unregister_all(PF_INET6);
1022
1023         udpv6_exit();
1024         udplitev6_exit();
1025         tcpv6_exit();
1026
1027         /* Cleanup code parts. */
1028         ipv6_packet_cleanup();
1029         ipv6_frag_exit();
1030         ipv6_exthdrs_exit();
1031         addrconf_cleanup();
1032         ip6_flowlabel_cleanup();
1033         ip6_route_cleanup();
1034 #ifdef CONFIG_PROC_FS
1035
1036         /* Cleanup code parts. */
1037         if6_proc_exit();
1038         ipv6_misc_proc_exit();
1039         udplite6_proc_exit();
1040         raw6_proc_exit();
1041 #endif
1042         ipv6_netfilter_fini();
1043         igmp6_cleanup();
1044         ndisc_cleanup();
1045         ip6_mr_cleanup();
1046         icmpv6_cleanup();
1047         rawv6_exit();
1048
1049         unregister_pernet_subsys(&inet6_net_ops);
1050         proto_unregister(&rawv6_prot);
1051         proto_unregister(&udplitev6_prot);
1052         proto_unregister(&udpv6_prot);
1053         proto_unregister(&tcpv6_prot);
1054
1055         rcu_barrier(); /* Wait for completion of call_rcu()'s */
1056 }
1057 module_exit(inet6_exit);
1058
1059 MODULE_ALIAS_NETPROTO(PF_INET6);