net/ipv6/af_inet6.c

   1 /*
   2  *      PF_INET6 socket protocol family
   3  *      Linux INET6 implementation
   4  *
   5  *      Authors:
   6  *      Pedro Roque             <roque@di.fc.ul.pt>
   7  *
   8  *      Adapted from linux/net/ipv4/af_inet.c
   9  *
  10  *      Fixes:
  11  *      piggy, Karl Knutson     :       Socket protocol table
  12  *      Hideaki YOSHIFUJI       :       sin6_scope_id support
  13  *      Arnaldo Melo            :       check proc_net_create return, cleanups
  14  *
  15  *      This program is free software; you can redistribute it and/or
  16  *      modify it under the terms of the GNU General Public License
  17  *      as published by the Free Software Foundation; either version
  18  *      2 of the License, or (at your option) any later version.
  19  */
  20
  21 #define pr_fmt(fmt) "IPv6: " fmt
  22
  23 #include <linux/module.h>
  24 #include <linux/capability.h>
  25 #include <linux/errno.h>
  26 #include <linux/types.h>
  27 #include <linux/socket.h>
  28 #include <linux/in.h>
  29 #include <linux/kernel.h>
  30 #include <linux/timer.h>
  31 #include <linux/string.h>
  32 #include <linux/sockios.h>
  33 #include <linux/net.h>
  34 #include <linux/fcntl.h>
  35 #include <linux/mm.h>
  36 #include <linux/interrupt.h>
  37 #include <linux/proc_fs.h>
  38 #include <linux/stat.h>
  39 #include <linux/init.h>
  40 #include <linux/slab.h>
  41
  42 #include <linux/inet.h>
  43 #include <linux/netdevice.h>
  44 #include <linux/icmpv6.h>
  45 #include <linux/netfilter_ipv6.h>
  46
  47 #include <net/ip.h>
  48 #include <net/ipv6.h>
  49 #include <net/udp.h>
  50 #include <net/udplite.h>
  51 #include <net/tcp.h>
  52 #include <net/ping.h>
  53 #include <net/protocol.h>
  54 #include <net/inet_common.h>
  55 #include <net/route.h>
  56 #include <net/transp_v6.h>
  57 #include <net/ip6_route.h>
  58 #include <net/addrconf.h>
  59 #include <net/ndisc.h>
  60 #ifdef CONFIG_IPV6_TUNNEL
  61 #include <net/ip6_tunnel.h>
  62 #endif
  63 #include <net/calipso.h>
  64 #include <net/seg6.h>
  65
  66 #include <linux/uaccess.h>
  67 #include <linux/mroute6.h>
  68
  69 #include "ip6_offload.h"
  70
  71 MODULE_AUTHOR("Cast of dozens");
  72 MODULE_DESCRIPTION("IPv6 protocol stack for Linux");
  73 MODULE_LICENSE("GPL");
  74
  75 /* The inetsw6 table contains everything that inet6_create needs to
  76  * build a new socket.
  77  */
  78 static struct list_head inetsw6[SOCK_MAX];
  79 static DEFINE_SPINLOCK(inetsw6_lock);
  80
  81 struct ipv6_params ipv6_defaults = {
  82         .disable_ipv6 = 0,
  83         .autoconf = 1,
  84 };
  85
  86 static int disable_ipv6_mod;
  87
  88 module_param_named(disable, disable_ipv6_mod, int, 0444);
  89 MODULE_PARM_DESC(disable, "Disable IPv6 module such that it is non-functional");
  90
  91 module_param_named(disable_ipv6, ipv6_defaults.disable_ipv6, int, 0444);
  92 MODULE_PARM_DESC(disable_ipv6, "Disable IPv6 on all interfaces");
  93
  94 module_param_named(autoconf, ipv6_defaults.autoconf, int, 0444);
  95 MODULE_PARM_DESC(autoconf, "Enable IPv6 address autoconfiguration on all interfaces");
  96
  97 bool ipv6_mod_enabled(void)
  98 {
  99         return disable_ipv6_mod == 0;
 100 }
 101 EXPORT_SYMBOL_GPL(ipv6_mod_enabled);
 102
 103 static __inline__ struct ipv6_pinfo *inet6_sk_generic(struct sock *sk)
 104 {
 105         const int offset = sk->sk_prot->obj_size - sizeof(struct ipv6_pinfo);
 106
 107         return (struct ipv6_pinfo *)(((u8 *)sk) + offset);
 108 }
 109
 110 static int inet6_create(struct net *net, struct socket *sock, int protocol,
 111                         int kern)
 112 {
 113         struct inet_sock *inet;
 114         struct ipv6_pinfo *np;
 115         struct sock *sk;
 116         struct inet_protosw *answer;
 117         struct proto *answer_prot;
 118         unsigned char answer_flags;
 119         int try_loading_module = 0;
 120         int err;
 121
 122         if (protocol < 0 || protocol >= IPPROTO_MAX)
 123                 return -EINVAL;
 124
 125         /* Look for the requested type/protocol pair. */
 126 lookup_protocol:
 127         err = -ESOCKTNOSUPPORT;
 128         rcu_read_lock();
 129         list_for_each_entry_rcu(answer, &inetsw6[sock->type], list) {
 130
 131                 err = 0;
 132                 /* Check the non-wild match. */
 133                 if (protocol == answer->protocol) {
 134                         if (protocol != IPPROTO_IP)
 135                                 break;
 136                 } else {
 137                         /* Check for the two wild cases. */
 138                         if (IPPROTO_IP == protocol) {
 139                                 protocol = answer->protocol;
 140                                 break;
 141                         }
 142                         if (IPPROTO_IP == answer->protocol)
 143                                 break;
 144                 }
 145                 err = -EPROTONOSUPPORT;
 146         }
 147
 148         if (err) {
 149                 if (try_loading_module < 2) {
 150                         rcu_read_unlock();
 151                         /*
 152                          * Be more specific, e.g. net-pf-10-proto-132-type-1
 153                          * (net-pf-PF_INET6-proto-IPPROTO_SCTP-type-SOCK_STREAM)
 154                          */
 155                         if (++try_loading_module == 1)
 156                                 request_module("net-pf-%d-proto-%d-type-%d",
 157                                                 PF_INET6, protocol, sock->type);
 158                         /*
 159                          * Fall back to generic, e.g. net-pf-10-proto-132
 160                          * (net-pf-PF_INET6-proto-IPPROTO_SCTP)
 161                          */
 162                         else
 163                                 request_module("net-pf-%d-proto-%d",
 164                                                 PF_INET6, protocol);
 165                         goto lookup_protocol;
 166                 } else
 167                         goto out_rcu_unlock;
 168         }
 169
 170         err = -EPERM;
 171         if (sock->type == SOCK_RAW && !kern &&
 172             !ns_capable(net->user_ns, CAP_NET_RAW))
 173                 goto out_rcu_unlock;
 174
 175         sock->ops = answer->ops;
 176         answer_prot = answer->prot;
 177         answer_flags = answer->flags;
 178         rcu_read_unlock();
 179
 180         WARN_ON(!answer_prot->slab);
 181
 182         err = -ENOBUFS;
 183         sk = sk_alloc(net, PF_INET6, GFP_KERNEL, answer_prot, kern);
 184         if (!sk)
 185                 goto out;
 186
 187         sock_init_data(sock, sk);
 188
 189         err = 0;
 190         if (INET_PROTOSW_REUSE & answer_flags)
 191                 sk->sk_reuse = SK_CAN_REUSE;
 192
 193         inet = inet_sk(sk);
 194         inet->is_icsk = (INET_PROTOSW_ICSK & answer_flags) != 0;
 195
 196         if (SOCK_RAW == sock->type) {
 197                 inet->inet_num = protocol;
 198                 if (IPPROTO_RAW == protocol)
 199                         inet->hdrincl = 1;
 200         }
 201
 202         sk->sk_destruct         = inet_sock_destruct;
 203         sk->sk_family           = PF_INET6;
 204         sk->sk_protocol         = protocol;
 205
 206         sk->sk_backlog_rcv      = answer->prot->backlog_rcv;
 207
 208         inet_sk(sk)->pinet6 = np = inet6_sk_generic(sk);
 209         np->hop_limit   = -1;
 210         np->mcast_hops  = IPV6_DEFAULT_MCASTHOPS;
 211         np->mc_loop     = 1;
 212         np->pmtudisc    = IPV6_PMTUDISC_WANT;
 213         np->repflow     = net->ipv6.sysctl.flowlabel_reflect;
 214         sk->sk_ipv6only = net->ipv6.sysctl.bindv6only;
 215
 216         /* Init the ipv4 part of the socket since we can have sockets
 217          * using v6 API for ipv4.
 218          */
 219         inet->uc_ttl    = -1;
 220
 221         inet->mc_loop   = 1;
 222         inet->mc_ttl    = 1;
 223         inet->mc_index  = 0;
 224         inet->mc_list   = NULL;
 225         inet->rcv_tos   = 0;
 226
 227         if (net->ipv4.sysctl_ip_no_pmtu_disc)
 228                 inet->pmtudisc = IP_PMTUDISC_DONT;
 229         else
 230                 inet->pmtudisc = IP_PMTUDISC_WANT;
 231         /*
 232          * Increment only the relevant sk_prot->socks debug field, this changes
 233          * the previous behaviour of incrementing both the equivalent to
 234          * answer->prot->socks (inet6_sock_nr) and inet_sock_nr.
 235          *
 236          * This allows better debug granularity as we'll know exactly how many
 237          * UDPv6, TCPv6, etc socks were allocated, not the sum of all IPv6
 238          * transport protocol socks. -acme
 239          */
 240         sk_refcnt_debug_inc(sk);
 241
 242         if (inet->inet_num) {
 243                 /* It assumes that any protocol which allows
 244                  * the user to assign a number at socket
 245                  * creation time automatically shares.
 246                  */
 247                 inet->inet_sport = htons(inet->inet_num);
 248                 err = sk->sk_prot->hash(sk);
 249                 if (err) {
 250                         sk_common_release(sk);
 251                         goto out;
 252                 }
 253         }
 254         if (sk->sk_prot->init) {
 255                 err = sk->sk_prot->init(sk);
 256                 if (err) {
 257                         sk_common_release(sk);
 258                         goto out;
 259                 }
 260         }
 261
 262         if (!kern) {
 263                 err = BPF_CGROUP_RUN_PROG_INET_SOCK(sk);
 264                 if (err) {
 265                         sk_common_release(sk);
 266                         goto out;
 267                 }
 268         }
 269 out:
 270         return err;
 271 out_rcu_unlock:
 272         rcu_read_unlock();
 273         goto out;
 274 }
 275
 276
 277 /* bind for INET6 API */
 278 int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 279 {
 280         struct sock *sk = sock->sk;
 281         int err = 0;
 282
 283         /* If the socket has its own bind function then use it. */
 284         if (sk->sk_prot->bind)
 285                 return sk->sk_prot->bind(sk, uaddr, addr_len);
 286
 287         if (addr_len < SIN6_LEN_RFC2133)
 288                 return -EINVAL;
 289
 290         /* BPF prog is run before any checks are done so that if the prog
 291          * changes context in a wrong way it will be caught.
 292          */
 293         err = BPF_CGROUP_RUN_PROG_INET6_BIND(sk, uaddr);
 294         if (err)
 295                 return err;
 296
 297         return __inet6_bind(sk, uaddr, addr_len, false, true);
 298 }
 299 EXPORT_SYMBOL(inet6_bind);
 300
 301 int __inet6_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len,
 302                  bool force_bind_address_no_port, bool with_lock)
 303 {
 304         struct sockaddr_in6 *addr = (struct sockaddr_in6 *)uaddr;
 305         struct inet_sock *inet = inet_sk(sk);
 306         struct ipv6_pinfo *np = inet6_sk(sk);
 307         struct net *net = sock_net(sk);
 308         __be32 v4addr = 0;
 309         unsigned short snum;
 310         bool saved_ipv6only;
 311         int addr_type = 0;
 312         int err = 0;
 313
 314         if (addr->sin6_family != AF_INET6)
 315                 return -EAFNOSUPPORT;
 316
 317         addr_type = ipv6_addr_type(&addr->sin6_addr);
 318         if ((addr_type & IPV6_ADDR_MULTICAST) && sk->sk_type == SOCK_STREAM)
 319                 return -EINVAL;
 320
 321         snum = ntohs(addr->sin6_port);
 322         if (snum && snum < inet_prot_sock(net) &&
 323             !ns_capable(net->user_ns, CAP_NET_BIND_SERVICE))
 324                 return -EACCES;
 325
 326         if (with_lock)
 327                 lock_sock(sk);
 328
 329         /* Check these errors (active socket, double bind). */
 330         if (sk->sk_state != TCP_CLOSE || inet->inet_num) {
 331                 err = -EINVAL;
 332                 goto out;
 333         }
 334
 335         /* Check if the address belongs to the host. */
 336         if (addr_type == IPV6_ADDR_MAPPED) {
 337                 int chk_addr_ret;
 338
 339                 /* Binding to v4-mapped address on a v6-only socket
 340                  * makes no sense
 341                  */
 342                 if (sk->sk_ipv6only) {
 343                         err = -EINVAL;
 344                         goto out;
 345                 }
 346
 347                 /* Reproduce AF_INET checks to make the bindings consistent */
 348                 v4addr = addr->sin6_addr.s6_addr32[3];
 349                 chk_addr_ret = inet_addr_type(net, v4addr);
 350                 if (!net->ipv4.sysctl_ip_nonlocal_bind &&
 351                     !(inet->freebind || inet->transparent) &&
 352                     v4addr != htonl(INADDR_ANY) &&
 353                     chk_addr_ret != RTN_LOCAL &&
 354                     chk_addr_ret != RTN_MULTICAST &&
 355                     chk_addr_ret != RTN_BROADCAST) {
 356                         err = -EADDRNOTAVAIL;
 357                         goto out;
 358                 }
 359         } else {
 360                 if (addr_type != IPV6_ADDR_ANY) {
 361                         struct net_device *dev = NULL;
 362
 363                         rcu_read_lock();
 364                         if (__ipv6_addr_needs_scope_id(addr_type)) {
 365                                 if (addr_len >= sizeof(struct sockaddr_in6) &&
 366                                     addr->sin6_scope_id) {
 367                                         /* Override any existing binding, if another one
 368                                          * is supplied by user.
 369                                          */
 370                                         sk->sk_bound_dev_if = addr->sin6_scope_id;
 371                                 }
 372
 373                                 /* Binding to link-local address requires an interface */
 374                                 if (!sk->sk_bound_dev_if) {
 375                                         err = -EINVAL;
 376                                         goto out_unlock;
 377                                 }
 378                                 dev = dev_get_by_index_rcu(net, sk->sk_bound_dev_if);
 379                                 if (!dev) {
 380                                         err = -ENODEV;
 381                                         goto out_unlock;
 382                                 }
 383                         }
 384
 385                         /* ipv4 addr of the socket is invalid.  Only the
 386                          * unspecified and mapped address have a v4 equivalent.
 387                          */
 388                         v4addr = LOOPBACK4_IPV6;
 389                         if (!(addr_type & IPV6_ADDR_MULTICAST)) {
 390                                 if (!net->ipv6.sysctl.ip_nonlocal_bind &&
 391                                     !(inet->freebind || inet->transparent) &&
 392                                     !ipv6_chk_addr(net, &addr->sin6_addr,
 393                                                    dev, 0)) {
 394                                         err = -EADDRNOTAVAIL;
 395                                         goto out_unlock;
 396                                 }
 397                         }
 398                         rcu_read_unlock();
 399                 }
 400         }
 401
 402         inet->inet_rcv_saddr = v4addr;
 403         inet->inet_saddr = v4addr;
 404
 405         sk->sk_v6_rcv_saddr = addr->sin6_addr;
 406
 407         if (!(addr_type & IPV6_ADDR_MULTICAST))
 408                 np->saddr = addr->sin6_addr;
 409
 410         saved_ipv6only = sk->sk_ipv6only;
 411         if (addr_type != IPV6_ADDR_ANY && addr_type != IPV6_ADDR_MAPPED)
 412                 sk->sk_ipv6only = 1;
 413
 414         /* Make sure we are allowed to bind here. */
 415         if (snum || !(inet->bind_address_no_port ||
 416                       force_bind_address_no_port)) {
 417                 if (sk->sk_prot->get_port(sk, snum)) {
 418                         sk->sk_ipv6only = saved_ipv6only;
 419                         inet_reset_saddr(sk);
 420                         err = -EADDRINUSE;
 421                         goto out;
 422                 }
 423                 err = BPF_CGROUP_RUN_PROG_INET6_POST_BIND(sk);
 424                 if (err) {
 425                         sk->sk_ipv6only = saved_ipv6only;
 426                         inet_reset_saddr(sk);
 427                         goto out;
 428                 }
 429         }
 430
 431         if (addr_type != IPV6_ADDR_ANY)
 432                 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
 433         if (snum)
 434                 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
 435         inet->inet_sport = htons(inet->inet_num);
 436         inet->inet_dport = 0;
 437         inet->inet_daddr = 0;
 438 out:
 439         if (with_lock)
 440                 release_sock(sk);
 441         return err;
 442 out_unlock:
 443         rcu_read_unlock();
 444         goto out;
 445 }
 446
 447 int inet6_release(struct socket *sock)
 448 {
 449         struct sock *sk = sock->sk;
 450
 451         if (!sk)
 452                 return -EINVAL;
 453
 454         /* Free mc lists */
 455         ipv6_sock_mc_close(sk);
 456
 457         /* Free ac lists */
 458         ipv6_sock_ac_close(sk);
 459
 460         return inet_release(sock);
 461 }
 462 EXPORT_SYMBOL(inet6_release);
 463
 464 void inet6_destroy_sock(struct sock *sk)
 465 {
 466         struct ipv6_pinfo *np = inet6_sk(sk);
 467         struct sk_buff *skb;
 468         struct ipv6_txoptions *opt;
 469
 470         /* Release rx options */
 471
 472         skb = xchg(&np->pktoptions, NULL);
 473         if (skb)
 474                 kfree_skb(skb);
 475
 476         skb = xchg(&np->rxpmtu, NULL);
 477         if (skb)
 478                 kfree_skb(skb);
 479
 480         /* Free flowlabels */
 481         fl6_free_socklist(sk);
 482
 483         /* Free tx options */
 484
 485         opt = xchg((__force struct ipv6_txoptions **)&np->opt, NULL);
 486         if (opt) {
 487                 atomic_sub(opt->tot_len, &sk->sk_omem_alloc);
 488                 txopt_put(opt);
 489         }
 490 }
 491 EXPORT_SYMBOL_GPL(inet6_destroy_sock);
 492
 493 /*
 494  *      This does both peername and sockname.
 495  */
 496
 497 int inet6_getname(struct socket *sock, struct sockaddr *uaddr,
 498                  int peer)
 499 {
 500         struct sockaddr_in6 *sin = (struct sockaddr_in6 *)uaddr;
 501         struct sock *sk = sock->sk;
 502         struct inet_sock *inet = inet_sk(sk);
 503         struct ipv6_pinfo *np = inet6_sk(sk);
 504
 505         sin->sin6_family = AF_INET6;
 506         sin->sin6_flowinfo = 0;
 507         sin->sin6_scope_id = 0;
 508         if (peer) {
 509                 if (!inet->inet_dport)
 510                         return -ENOTCONN;
 511                 if (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
 512                     peer == 1)
 513                         return -ENOTCONN;
 514                 sin->sin6_port = inet->inet_dport;
 515                 sin->sin6_addr = sk->sk_v6_daddr;
 516                 if (np->sndflow)
 517                         sin->sin6_flowinfo = np->flow_label;
 518         } else {
 519                 if (ipv6_addr_any(&sk->sk_v6_rcv_saddr))
 520                         sin->sin6_addr = np->saddr;
 521                 else
 522                         sin->sin6_addr = sk->sk_v6_rcv_saddr;
 523
 524                 sin->sin6_port = inet->inet_sport;
 525         }
 526         sin->sin6_scope_id = ipv6_iface_scope_id(&sin->sin6_addr,
 527                                                  sk->sk_bound_dev_if);
 528         return sizeof(*sin);
 529 }
 530 EXPORT_SYMBOL(inet6_getname);
 531
 532 int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
 533 {
 534         struct sock *sk = sock->sk;
 535         struct net *net = sock_net(sk);
 536
 537         switch (cmd) {
 538         case SIOCGSTAMP:
 539                 return sock_get_timestamp(sk, (struct timeval __user *)arg);
 540
 541         case SIOCGSTAMPNS:
 542                 return sock_get_timestampns(sk, (struct timespec __user *)arg);
 543
 544         case SIOCADDRT:
 545         case SIOCDELRT:
 546
 547                 return ipv6_route_ioctl(net, cmd, (void __user *)arg);
 548
 549         case SIOCSIFADDR:
 550                 return addrconf_add_ifaddr(net, (void __user *) arg);
 551         case SIOCDIFADDR:
 552                 return addrconf_del_ifaddr(net, (void __user *) arg);
 553         case SIOCSIFDSTADDR:
 554                 return addrconf_set_dstaddr(net, (void __user *) arg);
 555         default:
 556                 if (!sk->sk_prot->ioctl)
 557                         return -ENOIOCTLCMD;
 558                 return sk->sk_prot->ioctl(sk, cmd, arg);
 559         }
 560         /*NOTREACHED*/
 561         return 0;
 562 }
 563 EXPORT_SYMBOL(inet6_ioctl);
 564
 565 const struct proto_ops inet6_stream_ops = {
 566         .family            = PF_INET6,
 567         .owner             = THIS_MODULE,
 568         .release           = inet6_release,
 569         .bind              = inet6_bind,
 570         .connect           = inet_stream_connect,       /* ok           */
 571         .socketpair        = sock_no_socketpair,        /* a do nothing */
 572         .accept            = inet_accept,               /* ok           */
 573         .getname           = inet6_getname,
 574         .poll              = tcp_poll,                  /* ok           */
 575         .ioctl             = inet6_ioctl,               /* must change  */
 576         .listen            = inet_listen,               /* ok           */
 577         .shutdown          = inet_shutdown,             /* ok           */
 578         .setsockopt        = sock_common_setsockopt,    /* ok           */
 579         .getsockopt        = sock_common_getsockopt,    /* ok           */
 580         .sendmsg           = inet_sendmsg,              /* ok           */
 581         .recvmsg           = inet_recvmsg,              /* ok           */
 582         .mmap              = sock_no_mmap,
 583         .sendpage          = inet_sendpage,
 584         .sendmsg_locked    = tcp_sendmsg_locked,
 585         .sendpage_locked   = tcp_sendpage_locked,
 586         .splice_read       = tcp_splice_read,
 587         .read_sock         = tcp_read_sock,
 588         .peek_len          = tcp_peek_len,
 589 #ifdef CONFIG_COMPAT
 590         .compat_setsockopt = compat_sock_common_setsockopt,
 591         .compat_getsockopt = compat_sock_common_getsockopt,
 592 #endif
 593 };
 594
 595 const struct proto_ops inet6_dgram_ops = {
 596         .family            = PF_INET6,
 597         .owner             = THIS_MODULE,
 598         .release           = inet6_release,
 599         .bind              = inet6_bind,
 600         .connect           = inet_dgram_connect,        /* ok           */
 601         .socketpair        = sock_no_socketpair,        /* a do nothing */
 602         .accept            = sock_no_accept,            /* a do nothing */
 603         .getname           = inet6_getname,
 604         .poll              = udp_poll,                  /* ok           */
 605         .ioctl             = inet6_ioctl,               /* must change  */
 606         .listen            = sock_no_listen,            /* ok           */
 607         .shutdown          = inet_shutdown,             /* ok           */
 608         .setsockopt        = sock_common_setsockopt,    /* ok           */
 609         .getsockopt        = sock_common_getsockopt,    /* ok           */
 610         .sendmsg           = inet_sendmsg,              /* ok           */
 611         .recvmsg           = inet_recvmsg,              /* ok           */
 612         .mmap              = sock_no_mmap,
 613         .sendpage          = sock_no_sendpage,
 614         .set_peek_off      = sk_set_peek_off,
 615 #ifdef CONFIG_COMPAT
 616         .compat_setsockopt = compat_sock_common_setsockopt,
 617         .compat_getsockopt = compat_sock_common_getsockopt,
 618 #endif
 619 };
 620
 621 static const struct net_proto_family inet6_family_ops = {
 622         .family = PF_INET6,
 623         .create = inet6_create,
 624         .owner  = THIS_MODULE,
 625 };
 626
 627 int inet6_register_protosw(struct inet_protosw *p)
 628 {
 629         struct list_head *lh;
 630         struct inet_protosw *answer;
 631         struct list_head *last_perm;
 632         int protocol = p->protocol;
 633         int ret;
 634
 635         spin_lock_bh(&inetsw6_lock);
 636
 637         ret = -EINVAL;
 638         if (p->type >= SOCK_MAX)
 639                 goto out_illegal;
 640
 641         /* If we are trying to override a permanent protocol, bail. */
 642         answer = NULL;
 643         ret = -EPERM;
 644         last_perm = &inetsw6[p->type];
 645         list_for_each(lh, &inetsw6[p->type]) {
 646                 answer = list_entry(lh, struct inet_protosw, list);
 647
 648                 /* Check only the non-wild match. */
 649                 if (INET_PROTOSW_PERMANENT & answer->flags) {
 650                         if (protocol == answer->protocol)
 651                                 break;
 652                         last_perm = lh;
 653                 }
 654
 655                 answer = NULL;
 656         }
 657         if (answer)
 658                 goto out_permanent;
 659
 660         /* Add the new entry after the last permanent entry if any, so that
 661          * the new entry does not override a permanent entry when matched with
 662          * a wild-card protocol. But it is allowed to override any existing
 663          * non-permanent entry.  This means that when we remove this entry, the
 664          * system automatically returns to the old behavior.
 665          */
 666         list_add_rcu(&p->list, last_perm);
 667         ret = 0;
 668 out:
 669         spin_unlock_bh(&inetsw6_lock);
 670         return ret;
 671
 672 out_permanent:
 673         pr_err("Attempt to override permanent protocol %d\n", protocol);
 674         goto out;
 675
 676 out_illegal:
 677         pr_err("Ignoring attempt to register invalid socket type %d\n",
 678                p->type);
 679         goto out;
 680 }
 681 EXPORT_SYMBOL(inet6_register_protosw);
 682
 683 void
 684 inet6_unregister_protosw(struct inet_protosw *p)
 685 {
 686         if (INET_PROTOSW_PERMANENT & p->flags) {
 687                 pr_err("Attempt to unregister permanent protocol %d\n",
 688                        p->protocol);
 689         } else {
 690                 spin_lock_bh(&inetsw6_lock);
 691                 list_del_rcu(&p->list);
 692                 spin_unlock_bh(&inetsw6_lock);
 693
 694                 synchronize_net();
 695         }
 696 }
 697 EXPORT_SYMBOL(inet6_unregister_protosw);
 698
 699 int inet6_sk_rebuild_header(struct sock *sk)
 700 {
 701         struct ipv6_pinfo *np = inet6_sk(sk);
 702         struct dst_entry *dst;
 703
 704         dst = __sk_dst_check(sk, np->dst_cookie);
 705
 706         if (!dst) {
 707                 struct inet_sock *inet = inet_sk(sk);
 708                 struct in6_addr *final_p, final;
 709                 struct flowi6 fl6;
 710
 711                 memset(&fl6, 0, sizeof(fl6));
 712                 fl6.flowi6_proto = sk->sk_protocol;
 713                 fl6.daddr = sk->sk_v6_daddr;
 714                 fl6.saddr = np->saddr;
 715                 fl6.flowlabel = np->flow_label;
 716                 fl6.flowi6_oif = sk->sk_bound_dev_if;
 717                 fl6.flowi6_mark = sk->sk_mark;
 718                 fl6.fl6_dport = inet->inet_dport;
 719                 fl6.fl6_sport = inet->inet_sport;
 720                 fl6.flowi6_uid = sk->sk_uid;
 721                 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
 722
 723                 rcu_read_lock();
 724                 final_p = fl6_update_dst(&fl6, rcu_dereference(np->opt),
 725                                          &final);
 726                 rcu_read_unlock();
 727
 728                 dst = ip6_dst_lookup_flow(sk, &fl6, final_p);
 729                 if (IS_ERR(dst)) {
 730                         sk->sk_route_caps = 0;
 731                         sk->sk_err_soft = -PTR_ERR(dst);
 732                         return PTR_ERR(dst);
 733                 }
 734
 735                 ip6_dst_store(sk, dst, NULL, NULL);
 736         }
 737
 738         return 0;
 739 }
 740 EXPORT_SYMBOL_GPL(inet6_sk_rebuild_header);
 741
 742 bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb,
 743                        const struct inet6_skb_parm *opt)
 744 {
 745         const struct ipv6_pinfo *np = inet6_sk(sk);
 746
 747         if (np->rxopt.all) {
 748                 if (((opt->flags & IP6SKB_HOPBYHOP) &&
 749                      (np->rxopt.bits.hopopts || np->rxopt.bits.ohopopts)) ||
 750                     (ip6_flowinfo((struct ipv6hdr *) skb_network_header(skb)) &&
 751                      np->rxopt.bits.rxflow) ||
 752                     (opt->srcrt && (np->rxopt.bits.srcrt ||
 753                      np->rxopt.bits.osrcrt)) ||
 754                     ((opt->dst1 || opt->dst0) &&
 755                      (np->rxopt.bits.dstopts || np->rxopt.bits.odstopts)))
 756                         return true;
 757         }
 758         return false;
 759 }
 760 EXPORT_SYMBOL_GPL(ipv6_opt_accepted);
 761
 762 static struct packet_type ipv6_packet_type __read_mostly = {
 763         .type = cpu_to_be16(ETH_P_IPV6),
 764         .func = ipv6_rcv,
 765 };
 766
 767 static int __init ipv6_packet_init(void)
 768 {
 769         dev_add_pack(&ipv6_packet_type);
 770         return 0;
 771 }
 772
 773 static void ipv6_packet_cleanup(void)
 774 {
 775         dev_remove_pack(&ipv6_packet_type);
 776 }
 777
 778 static int __net_init ipv6_init_mibs(struct net *net)
 779 {
 780         int i;
 781
 782         net->mib.udp_stats_in6 = alloc_percpu(struct udp_mib);
 783         if (!net->mib.udp_stats_in6)
 784                 return -ENOMEM;
 785         net->mib.udplite_stats_in6 = alloc_percpu(struct udp_mib);
 786         if (!net->mib.udplite_stats_in6)
 787                 goto err_udplite_mib;
 788         net->mib.ipv6_statistics = alloc_percpu(struct ipstats_mib);
 789         if (!net->mib.ipv6_statistics)
 790                 goto err_ip_mib;
 791
 792         for_each_possible_cpu(i) {
 793                 struct ipstats_mib *af_inet6_stats;
 794                 af_inet6_stats = per_cpu_ptr(net->mib.ipv6_statistics, i);
 795                 u64_stats_init(&af_inet6_stats->syncp);
 796         }
 797
 798
 799         net->mib.icmpv6_statistics = alloc_percpu(struct icmpv6_mib);
 800         if (!net->mib.icmpv6_statistics)
 801                 goto err_icmp_mib;
 802         net->mib.icmpv6msg_statistics = kzalloc(sizeof(struct icmpv6msg_mib),
 803                                                 GFP_KERNEL);
 804         if (!net->mib.icmpv6msg_statistics)
 805                 goto err_icmpmsg_mib;
 806         return 0;
 807
 808 err_icmpmsg_mib:
 809         free_percpu(net->mib.icmpv6_statistics);
 810 err_icmp_mib:
 811         free_percpu(net->mib.ipv6_statistics);
 812 err_ip_mib:
 813         free_percpu(net->mib.udplite_stats_in6);
 814 err_udplite_mib:
 815         free_percpu(net->mib.udp_stats_in6);
 816         return -ENOMEM;
 817 }
 818
 819 static void ipv6_cleanup_mibs(struct net *net)
 820 {
 821         free_percpu(net->mib.udp_stats_in6);
 822         free_percpu(net->mib.udplite_stats_in6);
 823         free_percpu(net->mib.ipv6_statistics);
 824         free_percpu(net->mib.icmpv6_statistics);
 825         kfree(net->mib.icmpv6msg_statistics);
 826 }
 827
 828 static int __net_init inet6_net_init(struct net *net)
 829 {
 830         int err = 0;
 831
 832         net->ipv6.sysctl.bindv6only = 0;
 833         net->ipv6.sysctl.icmpv6_time = 1*HZ;
 834         net->ipv6.sysctl.flowlabel_consistency = 1;
 835         net->ipv6.sysctl.auto_flowlabels = IP6_DEFAULT_AUTO_FLOW_LABELS;
 836         net->ipv6.sysctl.idgen_retries = 3;
 837         net->ipv6.sysctl.idgen_delay = 1 * HZ;
 838         net->ipv6.sysctl.flowlabel_state_ranges = 0;
 839         net->ipv6.sysctl.max_dst_opts_cnt = IP6_DEFAULT_MAX_DST_OPTS_CNT;
 840         net->ipv6.sysctl.max_hbh_opts_cnt = IP6_DEFAULT_MAX_HBH_OPTS_CNT;
 841         net->ipv6.sysctl.max_dst_opts_len = IP6_DEFAULT_MAX_DST_OPTS_LEN;
 842         net->ipv6.sysctl.max_hbh_opts_len = IP6_DEFAULT_MAX_HBH_OPTS_LEN;
 843         atomic_set(&net->ipv6.fib6_sernum, 1);
 844
 845         err = ipv6_init_mibs(net);
 846         if (err)
 847                 return err;
 848 #ifdef CONFIG_PROC_FS
 849         err = udp6_proc_init(net);
 850         if (err)
 851                 goto out;
 852         err = tcp6_proc_init(net);
 853         if (err)
 854                 goto proc_tcp6_fail;
 855         err = ac6_proc_init(net);
 856         if (err)
 857                 goto proc_ac6_fail;
 858 #endif
 859         return err;
 860
 861 #ifdef CONFIG_PROC_FS
 862 proc_ac6_fail:
 863         tcp6_proc_exit(net);
 864 proc_tcp6_fail:
 865         udp6_proc_exit(net);
 866 out:
 867         ipv6_cleanup_mibs(net);
 868         return err;
 869 #endif
 870 }
 871
 872 static void __net_exit inet6_net_exit(struct net *net)
 873 {
 874 #ifdef CONFIG_PROC_FS
 875         udp6_proc_exit(net);
 876         tcp6_proc_exit(net);
 877         ac6_proc_exit(net);
 878 #endif
 879         ipv6_cleanup_mibs(net);
 880 }
 881
 882 static struct pernet_operations inet6_net_ops = {
 883         .init = inet6_net_init,
 884         .exit = inet6_net_exit,
 885 };
 886
 887 static const struct ipv6_stub ipv6_stub_impl = {
 888         .ipv6_sock_mc_join = ipv6_sock_mc_join,
 889         .ipv6_sock_mc_drop = ipv6_sock_mc_drop,
 890         .ipv6_dst_lookup = ip6_dst_lookup,
 891         .udpv6_encap_enable = udpv6_encap_enable,
 892         .ndisc_send_na = ndisc_send_na,
 893         .nd_tbl = &nd_tbl,
 894 };
 895
 896 static const struct ipv6_bpf_stub ipv6_bpf_stub_impl = {
 897         .inet6_bind = __inet6_bind,
 898 };
 899
 900 static int __init inet6_init(void)
 901 {
 902         struct list_head *r;
 903         int err = 0;
 904
 905         sock_skb_cb_check_size(sizeof(struct inet6_skb_parm));
 906
 907         /* Register the socket-side information for inet6_create.  */
 908         for (r = &inetsw6[0]; r < &inetsw6[SOCK_MAX]; ++r)
 909                 INIT_LIST_HEAD(r);
 910
 911         if (disable_ipv6_mod) {
 912                 pr_info("Loaded, but administratively disabled, reboot required to enable\n");
 913                 goto out;
 914         }
 915
 916         err = proto_register(&tcpv6_prot, 1);
 917         if (err)
 918                 goto out;
 919
 920         err = proto_register(&udpv6_prot, 1);
 921         if (err)
 922                 goto out_unregister_tcp_proto;
 923
 924         err = proto_register(&udplitev6_prot, 1);
 925         if (err)
 926                 goto out_unregister_udp_proto;
 927
 928         err = proto_register(&rawv6_prot, 1);
 929         if (err)
 930                 goto out_unregister_udplite_proto;
 931
 932         err = proto_register(&pingv6_prot, 1);
 933         if (err)
 934                 goto out_unregister_ping_proto;
 935
 936         /* We MUST register RAW sockets before we create the ICMP6,
 937          * IGMP6, or NDISC control sockets.
 938          */
 939         err = rawv6_init();
 940         if (err)
 941                 goto out_unregister_raw_proto;
 942
 943         /* Register the family here so that the init calls below will
 944          * be able to create sockets. (?? is this dangerous ??)
 945          */
 946         err = sock_register(&inet6_family_ops);
 947         if (err)
 948                 goto out_sock_register_fail;
 949
 950         /*
 951          *      ipngwg API draft makes clear that the correct semantics
 952          *      for TCP and UDP is to consider one TCP and UDP instance
 953          *      in a host available by both INET and INET6 APIs and
 954          *      able to communicate via both network protocols.
 955          */
 956
 957         err = register_pernet_subsys(&inet6_net_ops);
 958         if (err)
 959                 goto register_pernet_fail;
 960         err = ip6_mr_init();
 961         if (err)
 962                 goto ipmr_fail;
 963         err = icmpv6_init();
 964         if (err)
 965                 goto icmp_fail;
 966         err = ndisc_init();
 967         if (err)
 968                 goto ndisc_fail;
 969         err = igmp6_init();
 970         if (err)
 971                 goto igmp_fail;
 972
 973         err = ipv6_netfilter_init();
 974         if (err)
 975                 goto netfilter_fail;
 976         /* Create /proc/foo6 entries. */
 977 #ifdef CONFIG_PROC_FS
 978         err = -ENOMEM;
 979         if (raw6_proc_init())
 980                 goto proc_raw6_fail;
 981         if (udplite6_proc_init())
 982                 goto proc_udplite6_fail;
 983         if (ipv6_misc_proc_init())
 984                 goto proc_misc6_fail;
 985         if (if6_proc_init())
 986                 goto proc_if6_fail;
 987 #endif
 988         err = ip6_route_init();
 989         if (err)
 990                 goto ip6_route_fail;
 991         err = ndisc_late_init();
 992         if (err)
 993                 goto ndisc_late_fail;
 994         err = ip6_flowlabel_init();
 995         if (err)
 996                 goto ip6_flowlabel_fail;
 997         err = addrconf_init();
 998         if (err)
 999                 goto addrconf_fail;
1000
1001         /* Init v6 extension headers. */
1002         err = ipv6_exthdrs_init();
1003         if (err)
1004                 goto ipv6_exthdrs_fail;
1005
1006         err = ipv6_frag_init();
1007         if (err)
1008                 goto ipv6_frag_fail;
1009
1010         /* Init v6 transport protocols. */
1011         err = udpv6_init();
1012         if (err)
1013                 goto udpv6_fail;
1014
1015         err = udplitev6_init();
1016         if (err)
1017                 goto udplitev6_fail;
1018
1019         err = udpv6_offload_init();
1020         if (err)
1021                 goto udpv6_offload_fail;
1022
1023         err = tcpv6_init();
1024         if (err)
1025                 goto tcpv6_fail;
1026
1027         err = ipv6_packet_init();
1028         if (err)
1029                 goto ipv6_packet_fail;
1030
1031         err = pingv6_init();
1032         if (err)
1033                 goto pingv6_fail;
1034
1035         err = calipso_init();
1036         if (err)
1037                 goto calipso_fail;
1038
1039         err = seg6_init();
1040         if (err)
1041                 goto seg6_fail;
1042
1043         err = igmp6_late_init();
1044         if (err)
1045                 goto igmp6_late_err;
1046
1047 #ifdef CONFIG_SYSCTL
1048         err = ipv6_sysctl_register();
1049         if (err)
1050                 goto sysctl_fail;
1051 #endif
1052
1053         /* ensure that ipv6 stubs are visible only after ipv6 is ready */
1054         wmb();
1055         ipv6_stub = &ipv6_stub_impl;
1056         ipv6_bpf_stub = &ipv6_bpf_stub_impl;
1057 out:
1058         return err;
1059
1060 #ifdef CONFIG_SYSCTL
1061 sysctl_fail:
1062         igmp6_late_cleanup();
1063 #endif
1064 igmp6_late_err:
1065         seg6_exit();
1066 seg6_fail:
1067         calipso_exit();
1068 calipso_fail:
1069         pingv6_exit();
1070 pingv6_fail:
1071         ipv6_packet_cleanup();
1072 ipv6_packet_fail:
1073         tcpv6_exit();
1074 tcpv6_fail:
1075         udpv6_offload_exit();
1076 udpv6_offload_fail:
1077         udplitev6_exit();
1078 udplitev6_fail:
1079         udpv6_exit();
1080 udpv6_fail:
1081         ipv6_frag_exit();
1082 ipv6_frag_fail:
1083         ipv6_exthdrs_exit();
1084 ipv6_exthdrs_fail:
1085         addrconf_cleanup();
1086 addrconf_fail:
1087         ip6_flowlabel_cleanup();
1088 ip6_flowlabel_fail:
1089         ndisc_late_cleanup();
1090 ndisc_late_fail:
1091         ip6_route_cleanup();
1092 ip6_route_fail:
1093 #ifdef CONFIG_PROC_FS
1094         if6_proc_exit();
1095 proc_if6_fail:
1096         ipv6_misc_proc_exit();
1097 proc_misc6_fail:
1098         udplite6_proc_exit();
1099 proc_udplite6_fail:
1100         raw6_proc_exit();
1101 proc_raw6_fail:
1102 #endif
1103         ipv6_netfilter_fini();
1104 netfilter_fail:
1105         igmp6_cleanup();
1106 igmp_fail:
1107         ndisc_cleanup();
1108 ndisc_fail:
1109         ip6_mr_cleanup();
1110 icmp_fail:
1111         unregister_pernet_subsys(&inet6_net_ops);
1112 ipmr_fail:
1113         icmpv6_cleanup();
1114 register_pernet_fail:
1115         sock_unregister(PF_INET6);
1116         rtnl_unregister_all(PF_INET6);
1117 out_sock_register_fail:
1118         rawv6_exit();
1119 out_unregister_ping_proto:
1120         proto_unregister(&pingv6_prot);
1121 out_unregister_raw_proto:
1122         proto_unregister(&rawv6_prot);
1123 out_unregister_udplite_proto:
1124         proto_unregister(&udplitev6_prot);
1125 out_unregister_udp_proto:
1126         proto_unregister(&udpv6_prot);
1127 out_unregister_tcp_proto:
1128         proto_unregister(&tcpv6_prot);
1129         goto out;
1130 }
1131 module_init(inet6_init);
1132
1133 MODULE_ALIAS_NETPROTO(PF_INET6);