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/ipv6_stubs.h>
  60 #include <net/ndisc.h>
  61 #ifdef CONFIG_IPV6_TUNNEL
  62 #include <net/ip6_tunnel.h>
  63 #endif
  64 #include <net/calipso.h>
  65 #include <net/seg6.h>
  66
  67 #include <linux/uaccess.h>
  68 #include <linux/mroute6.h>
  69
  70 #include "ip6_offload.h"
  71
  72 MODULE_AUTHOR("Cast of dozens");
  73 MODULE_DESCRIPTION("IPv6 protocol stack for Linux");
  74 MODULE_LICENSE("GPL");
  75
  76 /* The inetsw6 table contains everything that inet6_create needs to
  77  * build a new socket.
  78  */
  79 static struct list_head inetsw6[SOCK_MAX];
  80 static DEFINE_SPINLOCK(inetsw6_lock);
  81
  82 struct ipv6_params ipv6_defaults = {
  83         .disable_ipv6 = 0,
  84         .autoconf = 1,
  85 };
  86
  87 static int disable_ipv6_mod;
  88
  89 module_param_named(disable, disable_ipv6_mod, int, 0444);
  90 MODULE_PARM_DESC(disable, "Disable IPv6 module such that it is non-functional");
  91
  92 module_param_named(disable_ipv6, ipv6_defaults.disable_ipv6, int, 0444);
  93 MODULE_PARM_DESC(disable_ipv6, "Disable IPv6 on all interfaces");
  94
  95 module_param_named(autoconf, ipv6_defaults.autoconf, int, 0444);
  96 MODULE_PARM_DESC(autoconf, "Enable IPv6 address autoconfiguration on all interfaces");
  97
  98 bool ipv6_mod_enabled(void)
  99 {
 100         return disable_ipv6_mod == 0;
 101 }
 102 EXPORT_SYMBOL_GPL(ipv6_mod_enabled);
 103
 104 static __inline__ struct ipv6_pinfo *inet6_sk_generic(struct sock *sk)
 105 {
 106         const int offset = sk->sk_prot->obj_size - sizeof(struct ipv6_pinfo);
 107
 108         return (struct ipv6_pinfo *)(((u8 *)sk) + offset);
 109 }
 110
 111 static int inet6_create(struct net *net, struct socket *sock, int protocol,
 112                         int kern)
 113 {
 114         struct inet_sock *inet;
 115         struct ipv6_pinfo *np;
 116         struct sock *sk;
 117         struct inet_protosw *answer;
 118         struct proto *answer_prot;
 119         unsigned char answer_flags;
 120         int try_loading_module = 0;
 121         int err;
 122
 123         if (protocol < 0 || protocol >= IPPROTO_MAX)
 124                 return -EINVAL;
 125
 126         /* Look for the requested type/protocol pair. */
 127 lookup_protocol:
 128         err = -ESOCKTNOSUPPORT;
 129         rcu_read_lock();
 130         list_for_each_entry_rcu(answer, &inetsw6[sock->type], list) {
 131
 132                 err = 0;
 133                 /* Check the non-wild match. */
 134                 if (protocol == answer->protocol) {
 135                         if (protocol != IPPROTO_IP)
 136                                 break;
 137                 } else {
 138                         /* Check for the two wild cases. */
 139                         if (IPPROTO_IP == protocol) {
 140                                 protocol = answer->protocol;
 141                                 break;
 142                         }
 143                         if (IPPROTO_IP == answer->protocol)
 144                                 break;
 145                 }
 146                 err = -EPROTONOSUPPORT;
 147         }
 148
 149         if (err) {
 150                 if (try_loading_module < 2) {
 151                         rcu_read_unlock();
 152                         /*
 153                          * Be more specific, e.g. net-pf-10-proto-132-type-1
 154                          * (net-pf-PF_INET6-proto-IPPROTO_SCTP-type-SOCK_STREAM)
 155                          */
 156                         if (++try_loading_module == 1)
 157                                 request_module("net-pf-%d-proto-%d-type-%d",
 158                                                 PF_INET6, protocol, sock->type);
 159                         /*
 160                          * Fall back to generic, e.g. net-pf-10-proto-132
 161                          * (net-pf-PF_INET6-proto-IPPROTO_SCTP)
 162                          */
 163                         else
 164                                 request_module("net-pf-%d-proto-%d",
 165                                                 PF_INET6, protocol);
 166                         goto lookup_protocol;
 167                 } else
 168                         goto out_rcu_unlock;
 169         }
 170
 171         err = -EPERM;
 172         if (sock->type == SOCK_RAW && !kern &&
 173             !ns_capable(net->user_ns, CAP_NET_RAW))
 174                 goto out_rcu_unlock;
 175
 176         sock->ops = answer->ops;
 177         answer_prot = answer->prot;
 178         answer_flags = answer->flags;
 179         rcu_read_unlock();
 180
 181         WARN_ON(!answer_prot->slab);
 182
 183         err = -ENOBUFS;
 184         sk = sk_alloc(net, PF_INET6, GFP_KERNEL, answer_prot, kern);
 185         if (!sk)
 186                 goto out;
 187
 188         sock_init_data(sock, sk);
 189
 190         err = 0;
 191         if (INET_PROTOSW_REUSE & answer_flags)
 192                 sk->sk_reuse = SK_CAN_REUSE;
 193
 194         inet = inet_sk(sk);
 195         inet->is_icsk = (INET_PROTOSW_ICSK & answer_flags) != 0;
 196
 197         if (SOCK_RAW == sock->type) {
 198                 inet->inet_num = protocol;
 199                 if (IPPROTO_RAW == protocol)
 200                         inet->hdrincl = 1;
 201         }
 202
 203         sk->sk_destruct         = inet_sock_destruct;
 204         sk->sk_family           = PF_INET6;
 205         sk->sk_protocol         = protocol;
 206
 207         sk->sk_backlog_rcv      = answer->prot->backlog_rcv;
 208
 209         inet_sk(sk)->pinet6 = np = inet6_sk_generic(sk);
 210         np->hop_limit   = -1;
 211         np->mcast_hops  = IPV6_DEFAULT_MCASTHOPS;
 212         np->mc_loop     = 1;
 213         np->mc_all      = 1;
 214         np->pmtudisc    = IPV6_PMTUDISC_WANT;
 215         np->repflow     = net->ipv6.sysctl.flowlabel_reflect;
 216         sk->sk_ipv6only = net->ipv6.sysctl.bindv6only;
 217
 218         /* Init the ipv4 part of the socket since we can have sockets
 219          * using v6 API for ipv4.
 220          */
 221         inet->uc_ttl    = -1;
 222
 223         inet->mc_loop   = 1;
 224         inet->mc_ttl    = 1;
 225         inet->mc_index  = 0;
 226         inet->mc_list   = NULL;
 227         inet->rcv_tos   = 0;
 228
 229         if (net->ipv4.sysctl_ip_no_pmtu_disc)
 230                 inet->pmtudisc = IP_PMTUDISC_DONT;
 231         else
 232                 inet->pmtudisc = IP_PMTUDISC_WANT;
 233         /*
 234          * Increment only the relevant sk_prot->socks debug field, this changes
 235          * the previous behaviour of incrementing both the equivalent to
 236          * answer->prot->socks (inet6_sock_nr) and inet_sock_nr.
 237          *
 238          * This allows better debug granularity as we'll know exactly how many
 239          * UDPv6, TCPv6, etc socks were allocated, not the sum of all IPv6
 240          * transport protocol socks. -acme
 241          */
 242         sk_refcnt_debug_inc(sk);
 243
 244         if (inet->inet_num) {
 245                 /* It assumes that any protocol which allows
 246                  * the user to assign a number at socket
 247                  * creation time automatically shares.
 248                  */
 249                 inet->inet_sport = htons(inet->inet_num);
 250                 err = sk->sk_prot->hash(sk);
 251                 if (err) {
 252                         sk_common_release(sk);
 253                         goto out;
 254                 }
 255         }
 256         if (sk->sk_prot->init) {
 257                 err = sk->sk_prot->init(sk);
 258                 if (err) {
 259                         sk_common_release(sk);
 260                         goto out;
 261                 }
 262         }
 263
 264         if (!kern) {
 265                 err = BPF_CGROUP_RUN_PROG_INET_SOCK(sk);
 266                 if (err) {
 267                         sk_common_release(sk);
 268                         goto out;
 269                 }
 270         }
 271 out:
 272         return err;
 273 out_rcu_unlock:
 274         rcu_read_unlock();
 275         goto out;
 276 }
 277
 278 static int __inet6_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len,
 279                         bool force_bind_address_no_port, bool with_lock)
 280 {
 281         struct sockaddr_in6 *addr = (struct sockaddr_in6 *)uaddr;
 282         struct inet_sock *inet = inet_sk(sk);
 283         struct ipv6_pinfo *np = inet6_sk(sk);
 284         struct net *net = sock_net(sk);
 285         __be32 v4addr = 0;
 286         unsigned short snum;
 287         bool saved_ipv6only;
 288         int addr_type = 0;
 289         int err = 0;
 290
 291         if (addr->sin6_family != AF_INET6)
 292                 return -EAFNOSUPPORT;
 293
 294         addr_type = ipv6_addr_type(&addr->sin6_addr);
 295         if ((addr_type & IPV6_ADDR_MULTICAST) && sk->sk_type == SOCK_STREAM)
 296                 return -EINVAL;
 297
 298         snum = ntohs(addr->sin6_port);
 299         if (snum && snum < inet_prot_sock(net) &&
 300             !ns_capable(net->user_ns, CAP_NET_BIND_SERVICE))
 301                 return -EACCES;
 302
 303         if (with_lock)
 304                 lock_sock(sk);
 305
 306         /* Check these errors (active socket, double bind). */
 307         if (sk->sk_state != TCP_CLOSE || inet->inet_num) {
 308                 err = -EINVAL;
 309                 goto out;
 310         }
 311
 312         /* Check if the address belongs to the host. */
 313         if (addr_type == IPV6_ADDR_MAPPED) {
 314                 struct net_device *dev = NULL;
 315                 int chk_addr_ret;
 316
 317                 /* Binding to v4-mapped address on a v6-only socket
 318                  * makes no sense
 319                  */
 320                 if (sk->sk_ipv6only) {
 321                         err = -EINVAL;
 322                         goto out;
 323                 }
 324
 325                 rcu_read_lock();
 326                 if (sk->sk_bound_dev_if) {
 327                         dev = dev_get_by_index_rcu(net, sk->sk_bound_dev_if);
 328                         if (!dev) {
 329                                 err = -ENODEV;
 330                                 goto out_unlock;
 331                         }
 332                 }
 333
 334                 /* Reproduce AF_INET checks to make the bindings consistent */
 335                 v4addr = addr->sin6_addr.s6_addr32[3];
 336                 chk_addr_ret = inet_addr_type_dev_table(net, dev, v4addr);
 337                 rcu_read_unlock();
 338
 339                 if (!inet_can_nonlocal_bind(net, inet) &&
 340                     v4addr != htonl(INADDR_ANY) &&
 341                     chk_addr_ret != RTN_LOCAL &&
 342                     chk_addr_ret != RTN_MULTICAST &&
 343                     chk_addr_ret != RTN_BROADCAST) {
 344                         err = -EADDRNOTAVAIL;
 345                         goto out;
 346                 }
 347         } else {
 348                 if (addr_type != IPV6_ADDR_ANY) {
 349                         struct net_device *dev = NULL;
 350
 351                         rcu_read_lock();
 352                         if (__ipv6_addr_needs_scope_id(addr_type)) {
 353                                 if (addr_len >= sizeof(struct sockaddr_in6) &&
 354                                     addr->sin6_scope_id) {
 355                                         /* Override any existing binding, if another one
 356                                          * is supplied by user.
 357                                          */
 358                                         sk->sk_bound_dev_if = addr->sin6_scope_id;
 359                                 }
 360
 361                                 /* Binding to link-local address requires an interface */
 362                                 if (!sk->sk_bound_dev_if) {
 363                                         err = -EINVAL;
 364                                         goto out_unlock;
 365                                 }
 366                         }
 367
 368                         if (sk->sk_bound_dev_if) {
 369                                 dev = dev_get_by_index_rcu(net, sk->sk_bound_dev_if);
 370                                 if (!dev) {
 371                                         err = -ENODEV;
 372                                         goto out_unlock;
 373                                 }
 374                         }
 375
 376                         /* ipv4 addr of the socket is invalid.  Only the
 377                          * unspecified and mapped address have a v4 equivalent.
 378                          */
 379                         v4addr = LOOPBACK4_IPV6;
 380                         if (!(addr_type & IPV6_ADDR_MULTICAST)) {
 381                                 if (!ipv6_can_nonlocal_bind(net, inet) &&
 382                                     !ipv6_chk_addr(net, &addr->sin6_addr,
 383                                                    dev, 0)) {
 384                                         err = -EADDRNOTAVAIL;
 385                                         goto out_unlock;
 386                                 }
 387                         }
 388                         rcu_read_unlock();
 389                 }
 390         }
 391
 392         inet->inet_rcv_saddr = v4addr;
 393         inet->inet_saddr = v4addr;
 394
 395         sk->sk_v6_rcv_saddr = addr->sin6_addr;
 396
 397         if (!(addr_type & IPV6_ADDR_MULTICAST))
 398                 np->saddr = addr->sin6_addr;
 399
 400         saved_ipv6only = sk->sk_ipv6only;
 401         if (addr_type != IPV6_ADDR_ANY && addr_type != IPV6_ADDR_MAPPED)
 402                 sk->sk_ipv6only = 1;
 403
 404         /* Make sure we are allowed to bind here. */
 405         if (snum || !(inet->bind_address_no_port ||
 406                       force_bind_address_no_port)) {
 407                 if (sk->sk_prot->get_port(sk, snum)) {
 408                         sk->sk_ipv6only = saved_ipv6only;
 409                         inet_reset_saddr(sk);
 410                         err = -EADDRINUSE;
 411                         goto out;
 412                 }
 413                 err = BPF_CGROUP_RUN_PROG_INET6_POST_BIND(sk);
 414                 if (err) {
 415                         sk->sk_ipv6only = saved_ipv6only;
 416                         inet_reset_saddr(sk);
 417                         goto out;
 418                 }
 419         }
 420
 421         if (addr_type != IPV6_ADDR_ANY)
 422                 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
 423         if (snum)
 424                 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
 425         inet->inet_sport = htons(inet->inet_num);
 426         inet->inet_dport = 0;
 427         inet->inet_daddr = 0;
 428 out:
 429         if (with_lock)
 430                 release_sock(sk);
 431         return err;
 432 out_unlock:
 433         rcu_read_unlock();
 434         goto out;
 435 }
 436
 437 /* bind for INET6 API */
 438 int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 439 {
 440         struct sock *sk = sock->sk;
 441         int err = 0;
 442
 443         /* If the socket has its own bind function then use it. */
 444         if (sk->sk_prot->bind)
 445                 return sk->sk_prot->bind(sk, uaddr, addr_len);
 446
 447         if (addr_len < SIN6_LEN_RFC2133)
 448                 return -EINVAL;
 449
 450         /* BPF prog is run before any checks are done so that if the prog
 451          * changes context in a wrong way it will be caught.
 452          */
 453         err = BPF_CGROUP_RUN_PROG_INET6_BIND(sk, uaddr);
 454         if (err)
 455                 return err;
 456
 457         return __inet6_bind(sk, uaddr, addr_len, false, true);
 458 }
 459 EXPORT_SYMBOL(inet6_bind);
 460
 461 int inet6_release(struct socket *sock)
 462 {
 463         struct sock *sk = sock->sk;
 464
 465         if (!sk)
 466                 return -EINVAL;
 467
 468         /* Free mc lists */
 469         ipv6_sock_mc_close(sk);
 470
 471         /* Free ac lists */
 472         ipv6_sock_ac_close(sk);
 473
 474         return inet_release(sock);
 475 }
 476 EXPORT_SYMBOL(inet6_release);
 477
 478 void inet6_destroy_sock(struct sock *sk)
 479 {
 480         struct ipv6_pinfo *np = inet6_sk(sk);
 481         struct sk_buff *skb;
 482         struct ipv6_txoptions *opt;
 483
 484         /* Release rx options */
 485
 486         skb = xchg(&np->pktoptions, NULL);
 487         kfree_skb(skb);
 488
 489         skb = xchg(&np->rxpmtu, NULL);
 490         kfree_skb(skb);
 491
 492         /* Free flowlabels */
 493         fl6_free_socklist(sk);
 494
 495         /* Free tx options */
 496
 497         opt = xchg((__force struct ipv6_txoptions **)&np->opt, NULL);
 498         if (opt) {
 499                 atomic_sub(opt->tot_len, &sk->sk_omem_alloc);
 500                 txopt_put(opt);
 501         }
 502 }
 503 EXPORT_SYMBOL_GPL(inet6_destroy_sock);
 504
 505 /*
 506  *      This does both peername and sockname.
 507  */
 508
 509 int inet6_getname(struct socket *sock, struct sockaddr *uaddr,
 510                  int peer)
 511 {
 512         struct sockaddr_in6 *sin = (struct sockaddr_in6 *)uaddr;
 513         struct sock *sk = sock->sk;
 514         struct inet_sock *inet = inet_sk(sk);
 515         struct ipv6_pinfo *np = inet6_sk(sk);
 516
 517         sin->sin6_family = AF_INET6;
 518         sin->sin6_flowinfo = 0;
 519         sin->sin6_scope_id = 0;
 520         if (peer) {
 521                 if (!inet->inet_dport)
 522                         return -ENOTCONN;
 523                 if (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
 524                     peer == 1)
 525                         return -ENOTCONN;
 526                 sin->sin6_port = inet->inet_dport;
 527                 sin->sin6_addr = sk->sk_v6_daddr;
 528                 if (np->sndflow)
 529                         sin->sin6_flowinfo = np->flow_label;
 530         } else {
 531                 if (ipv6_addr_any(&sk->sk_v6_rcv_saddr))
 532                         sin->sin6_addr = np->saddr;
 533                 else
 534                         sin->sin6_addr = sk->sk_v6_rcv_saddr;
 535
 536                 sin->sin6_port = inet->inet_sport;
 537         }
 538         sin->sin6_scope_id = ipv6_iface_scope_id(&sin->sin6_addr,
 539                                                  sk->sk_bound_dev_if);
 540         return sizeof(*sin);
 541 }
 542 EXPORT_SYMBOL(inet6_getname);
 543
 544 int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
 545 {
 546         struct sock *sk = sock->sk;
 547         struct net *net = sock_net(sk);
 548
 549         switch (cmd) {
 550         case SIOCADDRT:
 551         case SIOCDELRT:
 552
 553                 return ipv6_route_ioctl(net, cmd, (void __user *)arg);
 554
 555         case SIOCSIFADDR:
 556                 return addrconf_add_ifaddr(net, (void __user *) arg);
 557         case SIOCDIFADDR:
 558                 return addrconf_del_ifaddr(net, (void __user *) arg);
 559         case SIOCSIFDSTADDR:
 560                 return addrconf_set_dstaddr(net, (void __user *) arg);
 561         default:
 562                 if (!sk->sk_prot->ioctl)
 563                         return -ENOIOCTLCMD;
 564                 return sk->sk_prot->ioctl(sk, cmd, arg);
 565         }
 566         /*NOTREACHED*/
 567         return 0;
 568 }
 569 EXPORT_SYMBOL(inet6_ioctl);
 570
 571 const struct proto_ops inet6_stream_ops = {
 572         .family            = PF_INET6,
 573         .owner             = THIS_MODULE,
 574         .release           = inet6_release,
 575         .bind              = inet6_bind,
 576         .connect           = inet_stream_connect,       /* ok           */
 577         .socketpair        = sock_no_socketpair,        /* a do nothing */
 578         .accept            = inet_accept,               /* ok           */
 579         .getname           = inet6_getname,
 580         .poll              = tcp_poll,                  /* ok           */
 581         .ioctl             = inet6_ioctl,               /* must change  */
 582         .gettstamp         = sock_gettstamp,
 583         .listen            = inet_listen,               /* ok           */
 584         .shutdown          = inet_shutdown,             /* ok           */
 585         .setsockopt        = sock_common_setsockopt,    /* ok           */
 586         .getsockopt        = sock_common_getsockopt,    /* ok           */
 587         .sendmsg           = inet_sendmsg,              /* ok           */
 588         .recvmsg           = inet_recvmsg,              /* ok           */
 589 #ifdef CONFIG_MMU
 590         .mmap              = tcp_mmap,
 591 #endif
 592         .sendpage          = inet_sendpage,
 593         .sendmsg_locked    = tcp_sendmsg_locked,
 594         .sendpage_locked   = tcp_sendpage_locked,
 595         .splice_read       = tcp_splice_read,
 596         .read_sock         = tcp_read_sock,
 597         .peek_len          = tcp_peek_len,
 598 #ifdef CONFIG_COMPAT
 599         .compat_setsockopt = compat_sock_common_setsockopt,
 600         .compat_getsockopt = compat_sock_common_getsockopt,
 601 #endif
 602         .set_rcvlowat      = tcp_set_rcvlowat,
 603 };
 604
 605 const struct proto_ops inet6_dgram_ops = {
 606         .family            = PF_INET6,
 607         .owner             = THIS_MODULE,
 608         .release           = inet6_release,
 609         .bind              = inet6_bind,
 610         .connect           = inet_dgram_connect,        /* ok           */
 611         .socketpair        = sock_no_socketpair,        /* a do nothing */
 612         .accept            = sock_no_accept,            /* a do nothing */
 613         .getname           = inet6_getname,
 614         .poll              = udp_poll,                  /* ok           */
 615         .ioctl             = inet6_ioctl,               /* must change  */
 616         .gettstamp         = sock_gettstamp,
 617         .listen            = sock_no_listen,            /* ok           */
 618         .shutdown          = inet_shutdown,             /* ok           */
 619         .setsockopt        = sock_common_setsockopt,    /* ok           */
 620         .getsockopt        = sock_common_getsockopt,    /* ok           */
 621         .sendmsg           = inet_sendmsg,              /* ok           */
 622         .recvmsg           = inet_recvmsg,              /* ok           */
 623         .mmap              = sock_no_mmap,
 624         .sendpage          = sock_no_sendpage,
 625         .set_peek_off      = sk_set_peek_off,
 626 #ifdef CONFIG_COMPAT
 627         .compat_setsockopt = compat_sock_common_setsockopt,
 628         .compat_getsockopt = compat_sock_common_getsockopt,
 629 #endif
 630 };
 631
 632 static const struct net_proto_family inet6_family_ops = {
 633         .family = PF_INET6,
 634         .create = inet6_create,
 635         .owner  = THIS_MODULE,
 636 };
 637
 638 int inet6_register_protosw(struct inet_protosw *p)
 639 {
 640         struct list_head *lh;
 641         struct inet_protosw *answer;
 642         struct list_head *last_perm;
 643         int protocol = p->protocol;
 644         int ret;
 645
 646         spin_lock_bh(&inetsw6_lock);
 647
 648         ret = -EINVAL;
 649         if (p->type >= SOCK_MAX)
 650                 goto out_illegal;
 651
 652         /* If we are trying to override a permanent protocol, bail. */
 653         answer = NULL;
 654         ret = -EPERM;
 655         last_perm = &inetsw6[p->type];
 656         list_for_each(lh, &inetsw6[p->type]) {
 657                 answer = list_entry(lh, struct inet_protosw, list);
 658
 659                 /* Check only the non-wild match. */
 660                 if (INET_PROTOSW_PERMANENT & answer->flags) {
 661                         if (protocol == answer->protocol)
 662                                 break;
 663                         last_perm = lh;
 664                 }
 665
 666                 answer = NULL;
 667         }
 668         if (answer)
 669                 goto out_permanent;
 670
 671         /* Add the new entry after the last permanent entry if any, so that
 672          * the new entry does not override a permanent entry when matched with
 673          * a wild-card protocol. But it is allowed to override any existing
 674          * non-permanent entry.  This means that when we remove this entry, the
 675          * system automatically returns to the old behavior.
 676          */
 677         list_add_rcu(&p->list, last_perm);
 678         ret = 0;
 679 out:
 680         spin_unlock_bh(&inetsw6_lock);
 681         return ret;
 682
 683 out_permanent:
 684         pr_err("Attempt to override permanent protocol %d\n", protocol);
 685         goto out;
 686
 687 out_illegal:
 688         pr_err("Ignoring attempt to register invalid socket type %d\n",
 689                p->type);
 690         goto out;
 691 }
 692 EXPORT_SYMBOL(inet6_register_protosw);
 693
 694 void
 695 inet6_unregister_protosw(struct inet_protosw *p)
 696 {
 697         if (INET_PROTOSW_PERMANENT & p->flags) {
 698                 pr_err("Attempt to unregister permanent protocol %d\n",
 699                        p->protocol);
 700         } else {
 701                 spin_lock_bh(&inetsw6_lock);
 702                 list_del_rcu(&p->list);
 703                 spin_unlock_bh(&inetsw6_lock);
 704
 705                 synchronize_net();
 706         }
 707 }
 708 EXPORT_SYMBOL(inet6_unregister_protosw);
 709
 710 int inet6_sk_rebuild_header(struct sock *sk)
 711 {
 712         struct ipv6_pinfo *np = inet6_sk(sk);
 713         struct dst_entry *dst;
 714
 715         dst = __sk_dst_check(sk, np->dst_cookie);
 716
 717         if (!dst) {
 718                 struct inet_sock *inet = inet_sk(sk);
 719                 struct in6_addr *final_p, final;
 720                 struct flowi6 fl6;
 721
 722                 memset(&fl6, 0, sizeof(fl6));
 723                 fl6.flowi6_proto = sk->sk_protocol;
 724                 fl6.daddr = sk->sk_v6_daddr;
 725                 fl6.saddr = np->saddr;
 726                 fl6.flowlabel = np->flow_label;
 727                 fl6.flowi6_oif = sk->sk_bound_dev_if;
 728                 fl6.flowi6_mark = sk->sk_mark;
 729                 fl6.fl6_dport = inet->inet_dport;
 730                 fl6.fl6_sport = inet->inet_sport;
 731                 fl6.flowi6_uid = sk->sk_uid;
 732                 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
 733
 734                 rcu_read_lock();
 735                 final_p = fl6_update_dst(&fl6, rcu_dereference(np->opt),
 736                                          &final);
 737                 rcu_read_unlock();
 738
 739                 dst = ip6_dst_lookup_flow(sk, &fl6, final_p);
 740                 if (IS_ERR(dst)) {
 741                         sk->sk_route_caps = 0;
 742                         sk->sk_err_soft = -PTR_ERR(dst);
 743                         return PTR_ERR(dst);
 744                 }
 745
 746                 ip6_dst_store(sk, dst, NULL, NULL);
 747         }
 748
 749         return 0;
 750 }
 751 EXPORT_SYMBOL_GPL(inet6_sk_rebuild_header);
 752
 753 bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb,
 754                        const struct inet6_skb_parm *opt)
 755 {
 756         const struct ipv6_pinfo *np = inet6_sk(sk);
 757
 758         if (np->rxopt.all) {
 759                 if (((opt->flags & IP6SKB_HOPBYHOP) &&
 760                      (np->rxopt.bits.hopopts || np->rxopt.bits.ohopopts)) ||
 761                     (ip6_flowinfo((struct ipv6hdr *) skb_network_header(skb)) &&
 762                      np->rxopt.bits.rxflow) ||
 763                     (opt->srcrt && (np->rxopt.bits.srcrt ||
 764                      np->rxopt.bits.osrcrt)) ||
 765                     ((opt->dst1 || opt->dst0) &&
 766                      (np->rxopt.bits.dstopts || np->rxopt.bits.odstopts)))
 767                         return true;
 768         }
 769         return false;
 770 }
 771 EXPORT_SYMBOL_GPL(ipv6_opt_accepted);
 772
 773 static struct packet_type ipv6_packet_type __read_mostly = {
 774         .type = cpu_to_be16(ETH_P_IPV6),
 775         .func = ipv6_rcv,
 776         .list_func = ipv6_list_rcv,
 777 };
 778
 779 static int __init ipv6_packet_init(void)
 780 {
 781         dev_add_pack(&ipv6_packet_type);
 782         return 0;
 783 }
 784
 785 static void ipv6_packet_cleanup(void)
 786 {
 787         dev_remove_pack(&ipv6_packet_type);
 788 }
 789
 790 static int __net_init ipv6_init_mibs(struct net *net)
 791 {
 792         int i;
 793
 794         net->mib.udp_stats_in6 = alloc_percpu(struct udp_mib);
 795         if (!net->mib.udp_stats_in6)
 796                 return -ENOMEM;
 797         net->mib.udplite_stats_in6 = alloc_percpu(struct udp_mib);
 798         if (!net->mib.udplite_stats_in6)
 799                 goto err_udplite_mib;
 800         net->mib.ipv6_statistics = alloc_percpu(struct ipstats_mib);
 801         if (!net->mib.ipv6_statistics)
 802                 goto err_ip_mib;
 803
 804         for_each_possible_cpu(i) {
 805                 struct ipstats_mib *af_inet6_stats;
 806                 af_inet6_stats = per_cpu_ptr(net->mib.ipv6_statistics, i);
 807                 u64_stats_init(&af_inet6_stats->syncp);
 808         }
 809
 810
 811         net->mib.icmpv6_statistics = alloc_percpu(struct icmpv6_mib);
 812         if (!net->mib.icmpv6_statistics)
 813                 goto err_icmp_mib;
 814         net->mib.icmpv6msg_statistics = kzalloc(sizeof(struct icmpv6msg_mib),
 815                                                 GFP_KERNEL);
 816         if (!net->mib.icmpv6msg_statistics)
 817                 goto err_icmpmsg_mib;
 818         return 0;
 819
 820 err_icmpmsg_mib:
 821         free_percpu(net->mib.icmpv6_statistics);
 822 err_icmp_mib:
 823         free_percpu(net->mib.ipv6_statistics);
 824 err_ip_mib:
 825         free_percpu(net->mib.udplite_stats_in6);
 826 err_udplite_mib:
 827         free_percpu(net->mib.udp_stats_in6);
 828         return -ENOMEM;
 829 }
 830
 831 static void ipv6_cleanup_mibs(struct net *net)
 832 {
 833         free_percpu(net->mib.udp_stats_in6);
 834         free_percpu(net->mib.udplite_stats_in6);
 835         free_percpu(net->mib.ipv6_statistics);
 836         free_percpu(net->mib.icmpv6_statistics);
 837         kfree(net->mib.icmpv6msg_statistics);
 838 }
 839
 840 static int __net_init inet6_net_init(struct net *net)
 841 {
 842         int err = 0;
 843
 844         net->ipv6.sysctl.bindv6only = 0;
 845         net->ipv6.sysctl.icmpv6_time = 1*HZ;
 846         net->ipv6.sysctl.icmpv6_echo_ignore_all = 0;
 847         net->ipv6.sysctl.icmpv6_echo_ignore_multicast = 0;
 848         net->ipv6.sysctl.icmpv6_echo_ignore_anycast = 0;
 849
 850         /* By default, rate limit error messages.
 851          * Except for pmtu discovery, it would break it.
 852          * proc_do_large_bitmap needs pointer to the bitmap.
 853          */
 854         bitmap_set(net->ipv6.sysctl.icmpv6_ratemask, 0, ICMPV6_ERRMSG_MAX + 1);
 855         bitmap_clear(net->ipv6.sysctl.icmpv6_ratemask, ICMPV6_PKT_TOOBIG, 1);
 856         net->ipv6.sysctl.icmpv6_ratemask_ptr = net->ipv6.sysctl.icmpv6_ratemask;
 857
 858         net->ipv6.sysctl.flowlabel_consistency = 1;
 859         net->ipv6.sysctl.auto_flowlabels = IP6_DEFAULT_AUTO_FLOW_LABELS;
 860         net->ipv6.sysctl.idgen_retries = 3;
 861         net->ipv6.sysctl.idgen_delay = 1 * HZ;
 862         net->ipv6.sysctl.flowlabel_state_ranges = 0;
 863         net->ipv6.sysctl.max_dst_opts_cnt = IP6_DEFAULT_MAX_DST_OPTS_CNT;
 864         net->ipv6.sysctl.max_hbh_opts_cnt = IP6_DEFAULT_MAX_HBH_OPTS_CNT;
 865         net->ipv6.sysctl.max_dst_opts_len = IP6_DEFAULT_MAX_DST_OPTS_LEN;
 866         net->ipv6.sysctl.max_hbh_opts_len = IP6_DEFAULT_MAX_HBH_OPTS_LEN;
 867         atomic_set(&net->ipv6.fib6_sernum, 1);
 868
 869         err = ipv6_init_mibs(net);
 870         if (err)
 871                 return err;
 872 #ifdef CONFIG_PROC_FS
 873         err = udp6_proc_init(net);
 874         if (err)
 875                 goto out;
 876         err = tcp6_proc_init(net);
 877         if (err)
 878                 goto proc_tcp6_fail;
 879         err = ac6_proc_init(net);
 880         if (err)
 881                 goto proc_ac6_fail;
 882 #endif
 883         return err;
 884
 885 #ifdef CONFIG_PROC_FS
 886 proc_ac6_fail:
 887         tcp6_proc_exit(net);
 888 proc_tcp6_fail:
 889         udp6_proc_exit(net);
 890 out:
 891         ipv6_cleanup_mibs(net);
 892         return err;
 893 #endif
 894 }
 895
 896 static void __net_exit inet6_net_exit(struct net *net)
 897 {
 898 #ifdef CONFIG_PROC_FS
 899         udp6_proc_exit(net);
 900         tcp6_proc_exit(net);
 901         ac6_proc_exit(net);
 902 #endif
 903         ipv6_cleanup_mibs(net);
 904 }
 905
 906 static struct pernet_operations inet6_net_ops = {
 907         .init = inet6_net_init,
 908         .exit = inet6_net_exit,
 909 };
 910
 911 static int ipv6_route_input(struct sk_buff *skb)
 912 {
 913         ip6_route_input(skb);
 914         return skb_dst(skb)->error;
 915 }
 916
 917 static const struct ipv6_stub ipv6_stub_impl = {
 918         .ipv6_sock_mc_join = ipv6_sock_mc_join,
 919         .ipv6_sock_mc_drop = ipv6_sock_mc_drop,
 920         .ipv6_dst_lookup   = ip6_dst_lookup,
 921         .ipv6_route_input  = ipv6_route_input,
 922         .fib6_get_table    = fib6_get_table,
 923         .fib6_table_lookup = fib6_table_lookup,
 924         .fib6_lookup       = fib6_lookup,
 925         .fib6_select_path  = fib6_select_path,
 926         .ip6_mtu_from_fib6 = ip6_mtu_from_fib6,
 927         .fib6_nh_init      = fib6_nh_init,
 928         .fib6_nh_release   = fib6_nh_release,
 929         .fib6_update_sernum = fib6_update_sernum_stub,
 930         .ip6_del_rt        = ip6_del_rt,
 931         .udpv6_encap_enable = udpv6_encap_enable,
 932         .ndisc_send_na = ndisc_send_na,
 933         .nd_tbl = &nd_tbl,
 934 };
 935
 936 static const struct ipv6_bpf_stub ipv6_bpf_stub_impl = {
 937         .inet6_bind = __inet6_bind,
 938         .udp6_lib_lookup = __udp6_lib_lookup,
 939 };
 940
 941 static int __init inet6_init(void)
 942 {
 943         struct list_head *r;
 944         int err = 0;
 945
 946         sock_skb_cb_check_size(sizeof(struct inet6_skb_parm));
 947
 948         /* Register the socket-side information for inet6_create.  */
 949         for (r = &inetsw6[0]; r < &inetsw6[SOCK_MAX]; ++r)
 950                 INIT_LIST_HEAD(r);
 951
 952         if (disable_ipv6_mod) {
 953                 pr_info("Loaded, but administratively disabled, reboot required to enable\n");
 954                 goto out;
 955         }
 956
 957         err = proto_register(&tcpv6_prot, 1);
 958         if (err)
 959                 goto out;
 960
 961         err = proto_register(&udpv6_prot, 1);
 962         if (err)
 963                 goto out_unregister_tcp_proto;
 964
 965         err = proto_register(&udplitev6_prot, 1);
 966         if (err)
 967                 goto out_unregister_udp_proto;
 968
 969         err = proto_register(&rawv6_prot, 1);
 970         if (err)
 971                 goto out_unregister_udplite_proto;
 972
 973         err = proto_register(&pingv6_prot, 1);
 974         if (err)
 975                 goto out_unregister_raw_proto;
 976
 977         /* We MUST register RAW sockets before we create the ICMP6,
 978          * IGMP6, or NDISC control sockets.
 979          */
 980         err = rawv6_init();
 981         if (err)
 982                 goto out_unregister_ping_proto;
 983
 984         /* Register the family here so that the init calls below will
 985          * be able to create sockets. (?? is this dangerous ??)
 986          */
 987         err = sock_register(&inet6_family_ops);
 988         if (err)
 989                 goto out_sock_register_fail;
 990
 991         /*
 992          *      ipngwg API draft makes clear that the correct semantics
 993          *      for TCP and UDP is to consider one TCP and UDP instance
 994          *      in a host available by both INET and INET6 APIs and
 995          *      able to communicate via both network protocols.
 996          */
 997
 998         err = register_pernet_subsys(&inet6_net_ops);
 999         if (err)
1000                 goto register_pernet_fail;
1001         err = ip6_mr_init();
1002         if (err)
1003                 goto ipmr_fail;
1004         err = icmpv6_init();
1005         if (err)
1006                 goto icmp_fail;
1007         err = ndisc_init();
1008         if (err)
1009                 goto ndisc_fail;
1010         err = igmp6_init();
1011         if (err)
1012                 goto igmp_fail;
1013
1014         err = ipv6_netfilter_init();
1015         if (err)
1016                 goto netfilter_fail;
1017         /* Create /proc/foo6 entries. */
1018 #ifdef CONFIG_PROC_FS
1019         err = -ENOMEM;
1020         if (raw6_proc_init())
1021                 goto proc_raw6_fail;
1022         if (udplite6_proc_init())
1023                 goto proc_udplite6_fail;
1024         if (ipv6_misc_proc_init())
1025                 goto proc_misc6_fail;
1026         if (if6_proc_init())
1027                 goto proc_if6_fail;
1028 #endif
1029         err = ip6_route_init();
1030         if (err)
1031                 goto ip6_route_fail;
1032         err = ndisc_late_init();
1033         if (err)
1034                 goto ndisc_late_fail;
1035         err = ip6_flowlabel_init();
1036         if (err)
1037                 goto ip6_flowlabel_fail;
1038         err = ipv6_anycast_init();
1039         if (err)
1040                 goto ipv6_anycast_fail;
1041         err = addrconf_init();
1042         if (err)
1043                 goto addrconf_fail;
1044
1045         /* Init v6 extension headers. */
1046         err = ipv6_exthdrs_init();
1047         if (err)
1048                 goto ipv6_exthdrs_fail;
1049
1050         err = ipv6_frag_init();
1051         if (err)
1052                 goto ipv6_frag_fail;
1053
1054         /* Init v6 transport protocols. */
1055         err = udpv6_init();
1056         if (err)
1057                 goto udpv6_fail;
1058
1059         err = udplitev6_init();
1060         if (err)
1061                 goto udplitev6_fail;
1062
1063         err = udpv6_offload_init();
1064         if (err)
1065                 goto udpv6_offload_fail;
1066
1067         err = tcpv6_init();
1068         if (err)
1069                 goto tcpv6_fail;
1070
1071         err = ipv6_packet_init();
1072         if (err)
1073                 goto ipv6_packet_fail;
1074
1075         err = pingv6_init();
1076         if (err)
1077                 goto pingv6_fail;
1078
1079         err = calipso_init();
1080         if (err)
1081                 goto calipso_fail;
1082
1083         err = seg6_init();
1084         if (err)
1085                 goto seg6_fail;
1086
1087         err = igmp6_late_init();
1088         if (err)
1089                 goto igmp6_late_err;
1090
1091 #ifdef CONFIG_SYSCTL
1092         err = ipv6_sysctl_register();
1093         if (err)
1094                 goto sysctl_fail;
1095 #endif
1096
1097         /* ensure that ipv6 stubs are visible only after ipv6 is ready */
1098         wmb();
1099         ipv6_stub = &ipv6_stub_impl;
1100         ipv6_bpf_stub = &ipv6_bpf_stub_impl;
1101 out:
1102         return err;
1103
1104 #ifdef CONFIG_SYSCTL
1105 sysctl_fail:
1106         igmp6_late_cleanup();
1107 #endif
1108 igmp6_late_err:
1109         seg6_exit();
1110 seg6_fail:
1111         calipso_exit();
1112 calipso_fail:
1113         pingv6_exit();
1114 pingv6_fail:
1115         ipv6_packet_cleanup();
1116 ipv6_packet_fail:
1117         tcpv6_exit();
1118 tcpv6_fail:
1119         udpv6_offload_exit();
1120 udpv6_offload_fail:
1121         udplitev6_exit();
1122 udplitev6_fail:
1123         udpv6_exit();
1124 udpv6_fail:
1125         ipv6_frag_exit();
1126 ipv6_frag_fail:
1127         ipv6_exthdrs_exit();
1128 ipv6_exthdrs_fail:
1129         addrconf_cleanup();
1130 addrconf_fail:
1131         ipv6_anycast_cleanup();
1132 ipv6_anycast_fail:
1133         ip6_flowlabel_cleanup();
1134 ip6_flowlabel_fail:
1135         ndisc_late_cleanup();
1136 ndisc_late_fail:
1137         ip6_route_cleanup();
1138 ip6_route_fail:
1139 #ifdef CONFIG_PROC_FS
1140         if6_proc_exit();
1141 proc_if6_fail:
1142         ipv6_misc_proc_exit();
1143 proc_misc6_fail:
1144         udplite6_proc_exit();
1145 proc_udplite6_fail:
1146         raw6_proc_exit();
1147 proc_raw6_fail:
1148 #endif
1149         ipv6_netfilter_fini();
1150 netfilter_fail:
1151         igmp6_cleanup();
1152 igmp_fail:
1153         ndisc_cleanup();
1154 ndisc_fail:
1155         icmpv6_cleanup();
1156 icmp_fail:
1157         ip6_mr_cleanup();
1158 ipmr_fail:
1159         unregister_pernet_subsys(&inet6_net_ops);
1160 register_pernet_fail:
1161         sock_unregister(PF_INET6);
1162         rtnl_unregister_all(PF_INET6);
1163 out_sock_register_fail:
1164         rawv6_exit();
1165 out_unregister_ping_proto:
1166         proto_unregister(&pingv6_prot);
1167 out_unregister_raw_proto:
1168         proto_unregister(&rawv6_prot);
1169 out_unregister_udplite_proto:
1170         proto_unregister(&udplitev6_prot);
1171 out_unregister_udp_proto:
1172         proto_unregister(&udpv6_prot);
1173 out_unregister_tcp_proto:
1174         proto_unregister(&tcpv6_prot);
1175         goto out;
1176 }
1177 module_init(inet6_init);
1178
1179 MODULE_ALIAS_NETPROTO(PF_INET6);