linux/net/ipv6/af_inet6.c
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   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/ipip.h>
  53#include <net/protocol.h>
  54#include <net/inet_common.h>
  55#include <net/route.h>
  56#include <net/transp_v6.h>
  57#include <net/ip6_route.h>
  58#include <net/addrconf.h>
  59#ifdef CONFIG_IPV6_TUNNEL
  60#include <net/ip6_tunnel.h>
  61#endif
  62
  63#include <asm/uaccess.h>
  64#include <linux/mroute6.h>
  65
  66MODULE_AUTHOR("Cast of dozens");
  67MODULE_DESCRIPTION("IPv6 protocol stack for Linux");
  68MODULE_LICENSE("GPL");
  69
  70/* The inetsw6 table contains everything that inet6_create needs to
  71 * build a new socket.
  72 */
  73static struct list_head inetsw6[SOCK_MAX];
  74static DEFINE_SPINLOCK(inetsw6_lock);
  75
  76struct ipv6_params ipv6_defaults = {
  77        .disable_ipv6 = 0,
  78        .autoconf = 1,
  79};
  80
  81static int disable_ipv6_mod;
  82
  83module_param_named(disable, disable_ipv6_mod, int, 0444);
  84MODULE_PARM_DESC(disable, "Disable IPv6 module such that it is non-functional");
  85
  86module_param_named(disable_ipv6, ipv6_defaults.disable_ipv6, int, 0444);
  87MODULE_PARM_DESC(disable_ipv6, "Disable IPv6 on all interfaces");
  88
  89module_param_named(autoconf, ipv6_defaults.autoconf, int, 0444);
  90MODULE_PARM_DESC(autoconf, "Enable IPv6 address autoconfiguration on all interfaces");
  91
  92static __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
  99static 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. */
 118lookup_protocol:
 119        err = -ESOCKTNOSUPPORT;
 120        rcu_read_lock();
 121        list_for_each_entry_rcu(answer, &inetsw6[sock->type], list) {
 122
 123                err = 0;
 124                /* Check the non-wild match. */
 125                if (protocol == answer->protocol) {
 126                        if (protocol != IPPROTO_IP)
 127                                break;
 128                } else {
 129                        /* Check for the two wild cases. */
 130                        if (IPPROTO_IP == protocol) {
 131                                protocol = answer->protocol;
 132                                break;
 133                        }
 134                        if (IPPROTO_IP == answer->protocol)
 135                                break;
 136                }
 137                err = -EPROTONOSUPPORT;
 138        }
 139
 140        if (err) {
 141                if (try_loading_module < 2) {
 142                        rcu_read_unlock();
 143                        /*
 144                         * Be more specific, e.g. net-pf-10-proto-132-type-1
 145                         * (net-pf-PF_INET6-proto-IPPROTO_SCTP-type-SOCK_STREAM)
 146                         */
 147                        if (++try_loading_module == 1)
 148                                request_module("net-pf-%d-proto-%d-type-%d",
 149                                                PF_INET6, protocol, sock->type);
 150                        /*
 151                         * Fall back to generic, e.g. net-pf-10-proto-132
 152                         * (net-pf-PF_INET6-proto-IPPROTO_SCTP)
 153                         */
 154                        else
 155                                request_module("net-pf-%d-proto-%d",
 156                                                PF_INET6, protocol);
 157                        goto lookup_protocol;
 158                } else
 159                        goto out_rcu_unlock;
 160        }
 161
 162        err = -EPERM;
 163        if (sock->type == SOCK_RAW && !kern && !capable(CAP_NET_RAW))
 164                goto out_rcu_unlock;
 165
 166        sock->ops = answer->ops;
 167        answer_prot = answer->prot;
 168        answer_no_check = answer->no_check;
 169        answer_flags = answer->flags;
 170        rcu_read_unlock();
 171
 172        WARN_ON(answer_prot->slab == NULL);
 173
 174        err = -ENOBUFS;
 175        sk = sk_alloc(net, PF_INET6, GFP_KERNEL, answer_prot);
 176        if (sk == NULL)
 177                goto out;
 178
 179        sock_init_data(sock, sk);
 180
 181        err = 0;
 182        sk->sk_no_check = answer_no_check;
 183        if (INET_PROTOSW_REUSE & answer_flags)
 184                sk->sk_reuse = SK_CAN_REUSE;
 185
 186        inet = inet_sk(sk);
 187        inet->is_icsk = (INET_PROTOSW_ICSK & answer_flags) != 0;
 188
 189        if (SOCK_RAW == sock->type) {
 190                inet->inet_num = protocol;
 191                if (IPPROTO_RAW == protocol)
 192                        inet->hdrincl = 1;
 193        }
 194
 195        sk->sk_destruct         = inet_sock_destruct;
 196        sk->sk_family           = PF_INET6;
 197        sk->sk_protocol         = protocol;
 198
 199        sk->sk_backlog_rcv      = answer->prot->backlog_rcv;
 200
 201        inet_sk(sk)->pinet6 = np = inet6_sk_generic(sk);
 202        np->hop_limit   = -1;
 203        np->mcast_hops  = IPV6_DEFAULT_MCASTHOPS;
 204        np->mc_loop     = 1;
 205        np->pmtudisc    = IPV6_PMTUDISC_WANT;
 206        np->ipv6only    = net->ipv6.sysctl.bindv6only;
 207
 208        /* Init the ipv4 part of the socket since we can have sockets
 209         * using v6 API for ipv4.
 210         */
 211        inet->uc_ttl    = -1;
 212
 213        inet->mc_loop   = 1;
 214        inet->mc_ttl    = 1;
 215        inet->mc_index  = 0;
 216        inet->mc_list   = NULL;
 217        inet->rcv_tos   = 0;
 218
 219        if (ipv4_config.no_pmtu_disc)
 220                inet->pmtudisc = IP_PMTUDISC_DONT;
 221        else
 222                inet->pmtudisc = IP_PMTUDISC_WANT;
 223        /*
 224         * Increment only the relevant sk_prot->socks debug field, this changes
 225         * the previous behaviour of incrementing both the equivalent to
 226         * answer->prot->socks (inet6_sock_nr) and inet_sock_nr.
 227         *
 228         * This allows better debug granularity as we'll know exactly how many
 229         * UDPv6, TCPv6, etc socks were allocated, not the sum of all IPv6
 230         * transport protocol socks. -acme
 231         */
 232        sk_refcnt_debug_inc(sk);
 233
 234        if (inet->inet_num) {
 235                /* It assumes that any protocol which allows
 236                 * the user to assign a number at socket
 237                 * creation time automatically shares.
 238                 */
 239                inet->inet_sport = htons(inet->inet_num);
 240                sk->sk_prot->hash(sk);
 241        }
 242        if (sk->sk_prot->init) {
 243                err = sk->sk_prot->init(sk);
 244                if (err) {
 245                        sk_common_release(sk);
 246                        goto out;
 247                }
 248        }
 249out:
 250        return err;
 251out_rcu_unlock:
 252        rcu_read_unlock();
 253        goto out;
 254}
 255
 256
 257/* bind for INET6 API */
 258int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 259{
 260        struct sockaddr_in6 *addr = (struct sockaddr_in6 *)uaddr;
 261        struct sock *sk = sock->sk;
 262        struct inet_sock *inet = inet_sk(sk);
 263        struct ipv6_pinfo *np = inet6_sk(sk);
 264        struct net *net = sock_net(sk);
 265        __be32 v4addr = 0;
 266        unsigned short snum;
 267        int addr_type = 0;
 268        int err = 0;
 269
 270        /* If the socket has its own bind function then use it. */
 271        if (sk->sk_prot->bind)
 272                return sk->sk_prot->bind(sk, uaddr, addr_len);
 273
 274        if (addr_len < SIN6_LEN_RFC2133)
 275                return -EINVAL;
 276
 277        if (addr->sin6_family != AF_INET6)
 278                return -EAFNOSUPPORT;
 279
 280        addr_type = ipv6_addr_type(&addr->sin6_addr);
 281        if ((addr_type & IPV6_ADDR_MULTICAST) && sock->type == SOCK_STREAM)
 282                return -EINVAL;
 283
 284        snum = ntohs(addr->sin6_port);
 285        if (snum && snum < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE))
 286                return -EACCES;
 287
 288        lock_sock(sk);
 289
 290        /* Check these errors (active socket, double bind). */
 291        if (sk->sk_state != TCP_CLOSE || inet->inet_num) {
 292                err = -EINVAL;
 293                goto out;
 294        }
 295
 296        /* Check if the address belongs to the host. */
 297        if (addr_type == IPV6_ADDR_MAPPED) {
 298                int chk_addr_ret;
 299
 300                /* Binding to v4-mapped address on a v6-only socket
 301                 * makes no sense
 302                 */
 303                if (np->ipv6only) {
 304                        err = -EINVAL;
 305                        goto out;
 306                }
 307
 308                /* Reproduce AF_INET checks to make the bindings consistent */
 309                v4addr = addr->sin6_addr.s6_addr32[3];
 310                chk_addr_ret = inet_addr_type(net, v4addr);
 311                if (!sysctl_ip_nonlocal_bind &&
 312                    !(inet->freebind || inet->transparent) &&
 313                    v4addr != htonl(INADDR_ANY) &&
 314                    chk_addr_ret != RTN_LOCAL &&
 315                    chk_addr_ret != RTN_MULTICAST &&
 316                    chk_addr_ret != RTN_BROADCAST) {
 317                        err = -EADDRNOTAVAIL;
 318                        goto out;
 319                }
 320        } else {
 321                if (addr_type != IPV6_ADDR_ANY) {
 322                        struct net_device *dev = NULL;
 323
 324                        rcu_read_lock();
 325                        if (addr_type & IPV6_ADDR_LINKLOCAL) {
 326                                if (addr_len >= sizeof(struct sockaddr_in6) &&
 327                                    addr->sin6_scope_id) {
 328                                        /* Override any existing binding, if another one
 329                                         * is supplied by user.
 330                                         */
 331                                        sk->sk_bound_dev_if = addr->sin6_scope_id;
 332                                }
 333
 334                                /* Binding to link-local address requires an interface */
 335                                if (!sk->sk_bound_dev_if) {
 336                                        err = -EINVAL;
 337                                        goto out_unlock;
 338                                }
 339                                dev = dev_get_by_index_rcu(net, sk->sk_bound_dev_if);
 340                                if (!dev) {
 341                                        err = -ENODEV;
 342                                        goto out_unlock;
 343                                }
 344                        }
 345
 346                        /* ipv4 addr of the socket is invalid.  Only the
 347                         * unspecified and mapped address have a v4 equivalent.
 348                         */
 349                        v4addr = LOOPBACK4_IPV6;
 350                        if (!(addr_type & IPV6_ADDR_MULTICAST)) {
 351                                if (!(inet->freebind || inet->transparent) &&
 352                                    !ipv6_chk_addr(net, &addr->sin6_addr,
 353                                                   dev, 0)) {
 354                                        err = -EADDRNOTAVAIL;
 355                                        goto out_unlock;
 356                                }
 357                        }
 358                        rcu_read_unlock();
 359                }
 360        }
 361
 362        inet->inet_rcv_saddr = v4addr;
 363        inet->inet_saddr = v4addr;
 364
 365        np->rcv_saddr = addr->sin6_addr;
 366
 367        if (!(addr_type & IPV6_ADDR_MULTICAST))
 368                np->saddr = addr->sin6_addr;
 369
 370        /* Make sure we are allowed to bind here. */
 371        if (sk->sk_prot->get_port(sk, snum)) {
 372                inet_reset_saddr(sk);
 373                err = -EADDRINUSE;
 374                goto out;
 375        }
 376
 377        if (addr_type != IPV6_ADDR_ANY) {
 378                sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
 379                if (addr_type != IPV6_ADDR_MAPPED)
 380                        np->ipv6only = 1;
 381        }
 382        if (snum)
 383                sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
 384        inet->inet_sport = htons(inet->inet_num);
 385        inet->inet_dport = 0;
 386        inet->inet_daddr = 0;
 387out:
 388        release_sock(sk);
 389        return err;
 390out_unlock:
 391        rcu_read_unlock();
 392        goto out;
 393}
 394EXPORT_SYMBOL(inet6_bind);
 395
 396int inet6_release(struct socket *sock)
 397{
 398        struct sock *sk = sock->sk;
 399
 400        if (sk == NULL)
 401                return -EINVAL;
 402
 403        /* Free mc lists */
 404        ipv6_sock_mc_close(sk);
 405
 406        /* Free ac lists */
 407        ipv6_sock_ac_close(sk);
 408
 409        return inet_release(sock);
 410}
 411EXPORT_SYMBOL(inet6_release);
 412
 413void inet6_destroy_sock(struct sock *sk)
 414{
 415        struct ipv6_pinfo *np = inet6_sk(sk);
 416        struct sk_buff *skb;
 417        struct ipv6_txoptions *opt;
 418
 419        /* Release rx options */
 420
 421        skb = xchg(&np->pktoptions, NULL);
 422        if (skb != NULL)
 423                kfree_skb(skb);
 424
 425        skb = xchg(&np->rxpmtu, NULL);
 426        if (skb != NULL)
 427                kfree_skb(skb);
 428
 429        /* Free flowlabels */
 430        fl6_free_socklist(sk);
 431
 432        /* Free tx options */
 433
 434        opt = xchg(&np->opt, NULL);
 435        if (opt != NULL)
 436                sock_kfree_s(sk, opt, opt->tot_len);
 437}
 438EXPORT_SYMBOL_GPL(inet6_destroy_sock);
 439
 440/*
 441 *      This does both peername and sockname.
 442 */
 443
 444int inet6_getname(struct socket *sock, struct sockaddr *uaddr,
 445                 int *uaddr_len, int peer)
 446{
 447        struct sockaddr_in6 *sin = (struct sockaddr_in6 *)uaddr;
 448        struct sock *sk = sock->sk;
 449        struct inet_sock *inet = inet_sk(sk);
 450        struct ipv6_pinfo *np = inet6_sk(sk);
 451
 452        sin->sin6_family = AF_INET6;
 453        sin->sin6_flowinfo = 0;
 454        sin->sin6_scope_id = 0;
 455        if (peer) {
 456                if (!inet->inet_dport)
 457                        return -ENOTCONN;
 458                if (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
 459                    peer == 1)
 460                        return -ENOTCONN;
 461                sin->sin6_port = inet->inet_dport;
 462                sin->sin6_addr = np->daddr;
 463                if (np->sndflow)
 464                        sin->sin6_flowinfo = np->flow_label;
 465        } else {
 466                if (ipv6_addr_any(&np->rcv_saddr))
 467                        sin->sin6_addr = np->saddr;
 468                else
 469                        sin->sin6_addr = np->rcv_saddr;
 470
 471                sin->sin6_port = inet->inet_sport;
 472        }
 473        if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
 474                sin->sin6_scope_id = sk->sk_bound_dev_if;
 475        *uaddr_len = sizeof(*sin);
 476        return 0;
 477}
 478EXPORT_SYMBOL(inet6_getname);
 479
 480int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
 481{
 482        struct sock *sk = sock->sk;
 483        struct net *net = sock_net(sk);
 484
 485        switch (cmd) {
 486        case SIOCGSTAMP:
 487                return sock_get_timestamp(sk, (struct timeval __user *)arg);
 488
 489        case SIOCGSTAMPNS:
 490                return sock_get_timestampns(sk, (struct timespec __user *)arg);
 491
 492        case SIOCADDRT:
 493        case SIOCDELRT:
 494
 495                return ipv6_route_ioctl(net, cmd, (void __user *)arg);
 496
 497        case SIOCSIFADDR:
 498                return addrconf_add_ifaddr(net, (void __user *) arg);
 499        case SIOCDIFADDR:
 500                return addrconf_del_ifaddr(net, (void __user *) arg);
 501        case SIOCSIFDSTADDR:
 502                return addrconf_set_dstaddr(net, (void __user *) arg);
 503        default:
 504                if (!sk->sk_prot->ioctl)
 505                        return -ENOIOCTLCMD;
 506                return sk->sk_prot->ioctl(sk, cmd, arg);
 507        }
 508        /*NOTREACHED*/
 509        return 0;
 510}
 511EXPORT_SYMBOL(inet6_ioctl);
 512
 513const struct proto_ops inet6_stream_ops = {
 514        .family            = PF_INET6,
 515        .owner             = THIS_MODULE,
 516        .release           = inet6_release,
 517        .bind              = inet6_bind,
 518        .connect           = inet_stream_connect,       /* ok           */
 519        .socketpair        = sock_no_socketpair,        /* a do nothing */
 520        .accept            = inet_accept,               /* ok           */
 521        .getname           = inet6_getname,
 522        .poll              = tcp_poll,                  /* ok           */
 523        .ioctl             = inet6_ioctl,               /* must change  */
 524        .listen            = inet_listen,               /* ok           */
 525        .shutdown          = inet_shutdown,             /* ok           */
 526        .setsockopt        = sock_common_setsockopt,    /* ok           */
 527        .getsockopt        = sock_common_getsockopt,    /* ok           */
 528        .sendmsg           = inet_sendmsg,              /* ok           */
 529        .recvmsg           = inet_recvmsg,              /* ok           */
 530        .mmap              = sock_no_mmap,
 531        .sendpage          = inet_sendpage,
 532        .splice_read       = tcp_splice_read,
 533#ifdef CONFIG_COMPAT
 534        .compat_setsockopt = compat_sock_common_setsockopt,
 535        .compat_getsockopt = compat_sock_common_getsockopt,
 536#endif
 537};
 538
 539const struct proto_ops inet6_dgram_ops = {
 540        .family            = PF_INET6,
 541        .owner             = THIS_MODULE,
 542        .release           = inet6_release,
 543        .bind              = inet6_bind,
 544        .connect           = inet_dgram_connect,        /* ok           */
 545        .socketpair        = sock_no_socketpair,        /* a do nothing */
 546        .accept            = sock_no_accept,            /* a do nothing */
 547        .getname           = inet6_getname,
 548        .poll              = udp_poll,                  /* ok           */
 549        .ioctl             = inet6_ioctl,               /* must change  */
 550        .listen            = sock_no_listen,            /* ok           */
 551        .shutdown          = inet_shutdown,             /* ok           */
 552        .setsockopt        = sock_common_setsockopt,    /* ok           */
 553        .getsockopt        = sock_common_getsockopt,    /* ok           */
 554        .sendmsg           = inet_sendmsg,              /* ok           */
 555        .recvmsg           = inet_recvmsg,              /* ok           */
 556        .mmap              = sock_no_mmap,
 557        .sendpage          = sock_no_sendpage,
 558#ifdef CONFIG_COMPAT
 559        .compat_setsockopt = compat_sock_common_setsockopt,
 560        .compat_getsockopt = compat_sock_common_getsockopt,
 561#endif
 562};
 563
 564static const struct net_proto_family inet6_family_ops = {
 565        .family = PF_INET6,
 566        .create = inet6_create,
 567        .owner  = THIS_MODULE,
 568};
 569
 570int inet6_register_protosw(struct inet_protosw *p)
 571{
 572        struct list_head *lh;
 573        struct inet_protosw *answer;
 574        struct list_head *last_perm;
 575        int protocol = p->protocol;
 576        int ret;
 577
 578        spin_lock_bh(&inetsw6_lock);
 579
 580        ret = -EINVAL;
 581        if (p->type >= SOCK_MAX)
 582                goto out_illegal;
 583
 584        /* If we are trying to override a permanent protocol, bail. */
 585        answer = NULL;
 586        ret = -EPERM;
 587        last_perm = &inetsw6[p->type];
 588        list_for_each(lh, &inetsw6[p->type]) {
 589                answer = list_entry(lh, struct inet_protosw, list);
 590
 591                /* Check only the non-wild match. */
 592                if (INET_PROTOSW_PERMANENT & answer->flags) {
 593                        if (protocol == answer->protocol)
 594                                break;
 595                        last_perm = lh;
 596                }
 597
 598                answer = NULL;
 599        }
 600        if (answer)
 601                goto out_permanent;
 602
 603        /* Add the new entry after the last permanent entry if any, so that
 604         * the new entry does not override a permanent entry when matched with
 605         * a wild-card protocol. But it is allowed to override any existing
 606         * non-permanent entry.  This means that when we remove this entry, the
 607         * system automatically returns to the old behavior.
 608         */
 609        list_add_rcu(&p->list, last_perm);
 610        ret = 0;
 611out:
 612        spin_unlock_bh(&inetsw6_lock);
 613        return ret;
 614
 615out_permanent:
 616        pr_err("Attempt to override permanent protocol %d\n", protocol);
 617        goto out;
 618
 619out_illegal:
 620        pr_err("Ignoring attempt to register invalid socket type %d\n",
 621               p->type);
 622        goto out;
 623}
 624EXPORT_SYMBOL(inet6_register_protosw);
 625
 626void
 627inet6_unregister_protosw(struct inet_protosw *p)
 628{
 629        if (INET_PROTOSW_PERMANENT & p->flags) {
 630                pr_err("Attempt to unregister permanent protocol %d\n",
 631                       p->protocol);
 632        } else {
 633                spin_lock_bh(&inetsw6_lock);
 634                list_del_rcu(&p->list);
 635                spin_unlock_bh(&inetsw6_lock);
 636
 637                synchronize_net();
 638        }
 639}
 640EXPORT_SYMBOL(inet6_unregister_protosw);
 641
 642int inet6_sk_rebuild_header(struct sock *sk)
 643{
 644        struct ipv6_pinfo *np = inet6_sk(sk);
 645        struct dst_entry *dst;
 646
 647        dst = __sk_dst_check(sk, np->dst_cookie);
 648
 649        if (dst == NULL) {
 650                struct inet_sock *inet = inet_sk(sk);
 651                struct in6_addr *final_p, final;
 652                struct flowi6 fl6;
 653
 654                memset(&fl6, 0, sizeof(fl6));
 655                fl6.flowi6_proto = sk->sk_protocol;
 656                fl6.daddr = np->daddr;
 657                fl6.saddr = np->saddr;
 658                fl6.flowlabel = np->flow_label;
 659                fl6.flowi6_oif = sk->sk_bound_dev_if;
 660                fl6.flowi6_mark = sk->sk_mark;
 661                fl6.fl6_dport = inet->inet_dport;
 662                fl6.fl6_sport = inet->inet_sport;
 663                security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
 664
 665                final_p = fl6_update_dst(&fl6, np->opt, &final);
 666
 667                dst = ip6_dst_lookup_flow(sk, &fl6, final_p, false);
 668                if (IS_ERR(dst)) {
 669                        sk->sk_route_caps = 0;
 670                        sk->sk_err_soft = -PTR_ERR(dst);
 671                        return PTR_ERR(dst);
 672                }
 673
 674                __ip6_dst_store(sk, dst, NULL, NULL);
 675        }
 676
 677        return 0;
 678}
 679EXPORT_SYMBOL_GPL(inet6_sk_rebuild_header);
 680
 681bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb)
 682{
 683        const struct ipv6_pinfo *np = inet6_sk(sk);
 684        const struct inet6_skb_parm *opt = IP6CB(skb);
 685
 686        if (np->rxopt.all) {
 687                if ((opt->hop && (np->rxopt.bits.hopopts ||
 688                                  np->rxopt.bits.ohopopts)) ||
 689                    ((IPV6_FLOWINFO_MASK &
 690                      *(__be32 *)skb_network_header(skb)) &&
 691                     np->rxopt.bits.rxflow) ||
 692                    (opt->srcrt && (np->rxopt.bits.srcrt ||
 693                     np->rxopt.bits.osrcrt)) ||
 694                    ((opt->dst1 || opt->dst0) &&
 695                     (np->rxopt.bits.dstopts || np->rxopt.bits.odstopts)))
 696                        return true;
 697        }
 698        return false;
 699}
 700EXPORT_SYMBOL_GPL(ipv6_opt_accepted);
 701
 702static int ipv6_gso_pull_exthdrs(struct sk_buff *skb, int proto)
 703{
 704        const struct inet6_protocol *ops = NULL;
 705
 706        for (;;) {
 707                struct ipv6_opt_hdr *opth;
 708                int len;
 709
 710                if (proto != NEXTHDR_HOP) {
 711                        ops = rcu_dereference(inet6_protos[proto]);
 712
 713                        if (unlikely(!ops))
 714                                break;
 715
 716                        if (!(ops->flags & INET6_PROTO_GSO_EXTHDR))
 717                                break;
 718                }
 719
 720                if (unlikely(!pskb_may_pull(skb, 8)))
 721                        break;
 722
 723                opth = (void *)skb->data;
 724                len = ipv6_optlen(opth);
 725
 726                if (unlikely(!pskb_may_pull(skb, len)))
 727                        break;
 728
 729                proto = opth->nexthdr;
 730                __skb_pull(skb, len);
 731        }
 732
 733        return proto;
 734}
 735
 736static int ipv6_gso_send_check(struct sk_buff *skb)
 737{
 738        const struct ipv6hdr *ipv6h;
 739        const struct inet6_protocol *ops;
 740        int err = -EINVAL;
 741
 742        if (unlikely(!pskb_may_pull(skb, sizeof(*ipv6h))))
 743                goto out;
 744
 745        ipv6h = ipv6_hdr(skb);
 746        __skb_pull(skb, sizeof(*ipv6h));
 747        err = -EPROTONOSUPPORT;
 748
 749        rcu_read_lock();
 750        ops = rcu_dereference(inet6_protos[
 751                ipv6_gso_pull_exthdrs(skb, ipv6h->nexthdr)]);
 752
 753        if (likely(ops && ops->gso_send_check)) {
 754                skb_reset_transport_header(skb);
 755                err = ops->gso_send_check(skb);
 756        }
 757        rcu_read_unlock();
 758
 759out:
 760        return err;
 761}
 762
 763static struct sk_buff *ipv6_gso_segment(struct sk_buff *skb,
 764        netdev_features_t features)
 765{
 766        struct sk_buff *segs = ERR_PTR(-EINVAL);
 767        struct ipv6hdr *ipv6h;
 768        const struct inet6_protocol *ops;
 769        int proto;
 770        struct frag_hdr *fptr;
 771        unsigned int unfrag_ip6hlen;
 772        u8 *prevhdr;
 773        int offset = 0;
 774
 775        if (!(features & NETIF_F_V6_CSUM))
 776                features &= ~NETIF_F_SG;
 777
 778        if (unlikely(skb_shinfo(skb)->gso_type &
 779                     ~(SKB_GSO_UDP |
 780                       SKB_GSO_DODGY |
 781                       SKB_GSO_TCP_ECN |
 782                       SKB_GSO_TCPV6 |
 783                       0)))
 784                goto out;
 785
 786        if (unlikely(!pskb_may_pull(skb, sizeof(*ipv6h))))
 787                goto out;
 788
 789        ipv6h = ipv6_hdr(skb);
 790        __skb_pull(skb, sizeof(*ipv6h));
 791        segs = ERR_PTR(-EPROTONOSUPPORT);
 792
 793        proto = ipv6_gso_pull_exthdrs(skb, ipv6h->nexthdr);
 794        rcu_read_lock();
 795        ops = rcu_dereference(inet6_protos[proto]);
 796        if (likely(ops && ops->gso_segment)) {
 797                skb_reset_transport_header(skb);
 798                segs = ops->gso_segment(skb, features);
 799        }
 800        rcu_read_unlock();
 801
 802        if (IS_ERR(segs))
 803                goto out;
 804
 805        for (skb = segs; skb; skb = skb->next) {
 806                ipv6h = ipv6_hdr(skb);
 807                ipv6h->payload_len = htons(skb->len - skb->mac_len -
 808                                           sizeof(*ipv6h));
 809                if (proto == IPPROTO_UDP) {
 810                        unfrag_ip6hlen = ip6_find_1stfragopt(skb, &prevhdr);
 811                        fptr = (struct frag_hdr *)(skb_network_header(skb) +
 812                                unfrag_ip6hlen);
 813                        fptr->frag_off = htons(offset);
 814                        if (skb->next != NULL)
 815                                fptr->frag_off |= htons(IP6_MF);
 816                        offset += (ntohs(ipv6h->payload_len) -
 817                                   sizeof(struct frag_hdr));
 818                }
 819        }
 820
 821out:
 822        return segs;
 823}
 824
 825struct ipv6_gro_cb {
 826        struct napi_gro_cb napi;
 827        int proto;
 828};
 829
 830#define IPV6_GRO_CB(skb) ((struct ipv6_gro_cb *)(skb)->cb)
 831
 832static struct sk_buff **ipv6_gro_receive(struct sk_buff **head,
 833                                         struct sk_buff *skb)
 834{
 835        const struct inet6_protocol *ops;
 836        struct sk_buff **pp = NULL;
 837        struct sk_buff *p;
 838        struct ipv6hdr *iph;
 839        unsigned int nlen;
 840        unsigned int hlen;
 841        unsigned int off;
 842        int flush = 1;
 843        int proto;
 844        __wsum csum;
 845
 846        off = skb_gro_offset(skb);
 847        hlen = off + sizeof(*iph);
 848        iph = skb_gro_header_fast(skb, off);
 849        if (skb_gro_header_hard(skb, hlen)) {
 850                iph = skb_gro_header_slow(skb, hlen, off);
 851                if (unlikely(!iph))
 852                        goto out;
 853        }
 854
 855        skb_gro_pull(skb, sizeof(*iph));
 856        skb_set_transport_header(skb, skb_gro_offset(skb));
 857
 858        flush += ntohs(iph->payload_len) != skb_gro_len(skb);
 859
 860        rcu_read_lock();
 861        proto = iph->nexthdr;
 862        ops = rcu_dereference(inet6_protos[proto]);
 863        if (!ops || !ops->gro_receive) {
 864                __pskb_pull(skb, skb_gro_offset(skb));
 865                proto = ipv6_gso_pull_exthdrs(skb, proto);
 866                skb_gro_pull(skb, -skb_transport_offset(skb));
 867                skb_reset_transport_header(skb);
 868                __skb_push(skb, skb_gro_offset(skb));
 869
 870                ops = rcu_dereference(inet6_protos[proto]);
 871                if (!ops || !ops->gro_receive)
 872                        goto out_unlock;
 873
 874                iph = ipv6_hdr(skb);
 875        }
 876
 877        IPV6_GRO_CB(skb)->proto = proto;
 878
 879        flush--;
 880        nlen = skb_network_header_len(skb);
 881
 882        for (p = *head; p; p = p->next) {
 883                struct ipv6hdr *iph2;
 884
 885                if (!NAPI_GRO_CB(p)->same_flow)
 886                        continue;
 887
 888                iph2 = ipv6_hdr(p);
 889
 890                /* All fields must match except length. */
 891                if (nlen != skb_network_header_len(p) ||
 892                    memcmp(iph, iph2, offsetof(struct ipv6hdr, payload_len)) ||
 893                    memcmp(&iph->nexthdr, &iph2->nexthdr,
 894                           nlen - offsetof(struct ipv6hdr, nexthdr))) {
 895                        NAPI_GRO_CB(p)->same_flow = 0;
 896                        continue;
 897                }
 898
 899                NAPI_GRO_CB(p)->flush |= flush;
 900        }
 901
 902        NAPI_GRO_CB(skb)->flush |= flush;
 903
 904        csum = skb->csum;
 905        skb_postpull_rcsum(skb, iph, skb_network_header_len(skb));
 906
 907        pp = ops->gro_receive(head, skb);
 908
 909        skb->csum = csum;
 910
 911out_unlock:
 912        rcu_read_unlock();
 913
 914out:
 915        NAPI_GRO_CB(skb)->flush |= flush;
 916
 917        return pp;
 918}
 919
 920static int ipv6_gro_complete(struct sk_buff *skb)
 921{
 922        const struct inet6_protocol *ops;
 923        struct ipv6hdr *iph = ipv6_hdr(skb);
 924        int err = -ENOSYS;
 925
 926        iph->payload_len = htons(skb->len - skb_network_offset(skb) -
 927                                 sizeof(*iph));
 928
 929        rcu_read_lock();
 930        ops = rcu_dereference(inet6_protos[IPV6_GRO_CB(skb)->proto]);
 931        if (WARN_ON(!ops || !ops->gro_complete))
 932                goto out_unlock;
 933
 934        err = ops->gro_complete(skb);
 935
 936out_unlock:
 937        rcu_read_unlock();
 938
 939        return err;
 940}
 941
 942static struct packet_type ipv6_packet_type __read_mostly = {
 943        .type = cpu_to_be16(ETH_P_IPV6),
 944        .func = ipv6_rcv,
 945        .gso_send_check = ipv6_gso_send_check,
 946        .gso_segment = ipv6_gso_segment,
 947        .gro_receive = ipv6_gro_receive,
 948        .gro_complete = ipv6_gro_complete,
 949};
 950
 951static int __init ipv6_packet_init(void)
 952{
 953        dev_add_pack(&ipv6_packet_type);
 954        return 0;
 955}
 956
 957static void ipv6_packet_cleanup(void)
 958{
 959        dev_remove_pack(&ipv6_packet_type);
 960}
 961
 962static int __net_init ipv6_init_mibs(struct net *net)
 963{
 964        if (snmp_mib_init((void __percpu **)net->mib.udp_stats_in6,
 965                          sizeof(struct udp_mib),
 966                          __alignof__(struct udp_mib)) < 0)
 967                return -ENOMEM;
 968        if (snmp_mib_init((void __percpu **)net->mib.udplite_stats_in6,
 969                          sizeof(struct udp_mib),
 970                          __alignof__(struct udp_mib)) < 0)
 971                goto err_udplite_mib;
 972        if (snmp_mib_init((void __percpu **)net->mib.ipv6_statistics,
 973                          sizeof(struct ipstats_mib),
 974                          __alignof__(struct ipstats_mib)) < 0)
 975                goto err_ip_mib;
 976        if (snmp_mib_init((void __percpu **)net->mib.icmpv6_statistics,
 977                          sizeof(struct icmpv6_mib),
 978                          __alignof__(struct icmpv6_mib)) < 0)
 979                goto err_icmp_mib;
 980        net->mib.icmpv6msg_statistics = kzalloc(sizeof(struct icmpv6msg_mib),
 981                                                GFP_KERNEL);
 982        if (!net->mib.icmpv6msg_statistics)
 983                goto err_icmpmsg_mib;
 984        return 0;
 985
 986err_icmpmsg_mib:
 987        snmp_mib_free((void __percpu **)net->mib.icmpv6_statistics);
 988err_icmp_mib:
 989        snmp_mib_free((void __percpu **)net->mib.ipv6_statistics);
 990err_ip_mib:
 991        snmp_mib_free((void __percpu **)net->mib.udplite_stats_in6);
 992err_udplite_mib:
 993        snmp_mib_free((void __percpu **)net->mib.udp_stats_in6);
 994        return -ENOMEM;
 995}
 996
 997static void ipv6_cleanup_mibs(struct net *net)
 998{
 999        snmp_mib_free((void __percpu **)net->mib.udp_stats_in6);
1000        snmp_mib_free((void __percpu **)net->mib.udplite_stats_in6);
1001        snmp_mib_free((void __percpu **)net->mib.ipv6_statistics);
1002        snmp_mib_free((void __percpu **)net->mib.icmpv6_statistics);
1003        kfree(net->mib.icmpv6msg_statistics);
1004}
1005
1006static int __net_init inet6_net_init(struct net *net)
1007{
1008        int err = 0;
1009
1010        net->ipv6.sysctl.bindv6only = 0;
1011        net->ipv6.sysctl.icmpv6_time = 1*HZ;
1012
1013        err = ipv6_init_mibs(net);
1014        if (err)
1015                return err;
1016#ifdef CONFIG_PROC_FS
1017        err = udp6_proc_init(net);
1018        if (err)
1019                goto out;
1020        err = tcp6_proc_init(net);
1021        if (err)
1022                goto proc_tcp6_fail;
1023        err = ac6_proc_init(net);
1024        if (err)
1025                goto proc_ac6_fail;
1026#endif
1027        return err;
1028
1029#ifdef CONFIG_PROC_FS
1030proc_ac6_fail:
1031        tcp6_proc_exit(net);
1032proc_tcp6_fail:
1033        udp6_proc_exit(net);
1034out:
1035        ipv6_cleanup_mibs(net);
1036        return err;
1037#endif
1038}
1039
1040static void __net_exit inet6_net_exit(struct net *net)
1041{
1042#ifdef CONFIG_PROC_FS
1043        udp6_proc_exit(net);
1044        tcp6_proc_exit(net);
1045        ac6_proc_exit(net);
1046#endif
1047        ipv6_cleanup_mibs(net);
1048}
1049
1050static struct pernet_operations inet6_net_ops = {
1051        .init = inet6_net_init,
1052        .exit = inet6_net_exit,
1053};
1054
1055static int __init inet6_init(void)
1056{
1057        struct sk_buff *dummy_skb;
1058        struct list_head *r;
1059        int err = 0;
1060
1061        BUILD_BUG_ON(sizeof(struct inet6_skb_parm) > sizeof(dummy_skb->cb));
1062
1063        /* Register the socket-side information for inet6_create.  */
1064        for (r = &inetsw6[0]; r < &inetsw6[SOCK_MAX]; ++r)
1065                INIT_LIST_HEAD(r);
1066
1067        if (disable_ipv6_mod) {
1068                pr_info("Loaded, but administratively disabled, reboot required to enable\n");
1069                goto out;
1070        }
1071
1072        err = proto_register(&tcpv6_prot, 1);
1073        if (err)
1074                goto out;
1075
1076        err = proto_register(&udpv6_prot, 1);
1077        if (err)
1078                goto out_unregister_tcp_proto;
1079
1080        err = proto_register(&udplitev6_prot, 1);
1081        if (err)
1082                goto out_unregister_udp_proto;
1083
1084        err = proto_register(&rawv6_prot, 1);
1085        if (err)
1086                goto out_unregister_udplite_proto;
1087
1088
1089        /* We MUST register RAW sockets before we create the ICMP6,
1090         * IGMP6, or NDISC control sockets.
1091         */
1092        err = rawv6_init();
1093        if (err)
1094                goto out_unregister_raw_proto;
1095
1096        /* Register the family here so that the init calls below will
1097         * be able to create sockets. (?? is this dangerous ??)
1098         */
1099        err = sock_register(&inet6_family_ops);
1100        if (err)
1101                goto out_sock_register_fail;
1102
1103        tcpv6_prot.sysctl_mem = init_net.ipv4.sysctl_tcp_mem;
1104
1105        /*
1106         *      ipngwg API draft makes clear that the correct semantics
1107         *      for TCP and UDP is to consider one TCP and UDP instance
1108         *      in a host available by both INET and INET6 APIs and
1109         *      able to communicate via both network protocols.
1110         */
1111
1112        err = register_pernet_subsys(&inet6_net_ops);
1113        if (err)
1114                goto register_pernet_fail;
1115        err = icmpv6_init();
1116        if (err)
1117                goto icmp_fail;
1118        err = ip6_mr_init();
1119        if (err)
1120                goto ipmr_fail;
1121        err = ndisc_init();
1122        if (err)
1123                goto ndisc_fail;
1124        err = igmp6_init();
1125        if (err)
1126                goto igmp_fail;
1127        err = ipv6_netfilter_init();
1128        if (err)
1129                goto netfilter_fail;
1130        /* Create /proc/foo6 entries. */
1131#ifdef CONFIG_PROC_FS
1132        err = -ENOMEM;
1133        if (raw6_proc_init())
1134                goto proc_raw6_fail;
1135        if (udplite6_proc_init())
1136                goto proc_udplite6_fail;
1137        if (ipv6_misc_proc_init())
1138                goto proc_misc6_fail;
1139        if (if6_proc_init())
1140                goto proc_if6_fail;
1141#endif
1142        err = ip6_route_init();
1143        if (err)
1144                goto ip6_route_fail;
1145        err = ip6_flowlabel_init();
1146        if (err)
1147                goto ip6_flowlabel_fail;
1148        err = addrconf_init();
1149        if (err)
1150                goto addrconf_fail;
1151
1152        /* Init v6 extension headers. */
1153        err = ipv6_exthdrs_init();
1154        if (err)
1155                goto ipv6_exthdrs_fail;
1156
1157        err = ipv6_frag_init();
1158        if (err)
1159                goto ipv6_frag_fail;
1160
1161        /* Init v6 transport protocols. */
1162        err = udpv6_init();
1163        if (err)
1164                goto udpv6_fail;
1165
1166        err = udplitev6_init();
1167        if (err)
1168                goto udplitev6_fail;
1169
1170        err = tcpv6_init();
1171        if (err)
1172                goto tcpv6_fail;
1173
1174        err = ipv6_packet_init();
1175        if (err)
1176                goto ipv6_packet_fail;
1177
1178#ifdef CONFIG_SYSCTL
1179        err = ipv6_sysctl_register();
1180        if (err)
1181                goto sysctl_fail;
1182#endif
1183out:
1184        return err;
1185
1186#ifdef CONFIG_SYSCTL
1187sysctl_fail:
1188        ipv6_packet_cleanup();
1189#endif
1190ipv6_packet_fail:
1191        tcpv6_exit();
1192tcpv6_fail:
1193        udplitev6_exit();
1194udplitev6_fail:
1195        udpv6_exit();
1196udpv6_fail:
1197        ipv6_frag_exit();
1198ipv6_frag_fail:
1199        ipv6_exthdrs_exit();
1200ipv6_exthdrs_fail:
1201        addrconf_cleanup();
1202addrconf_fail:
1203        ip6_flowlabel_cleanup();
1204ip6_flowlabel_fail:
1205        ip6_route_cleanup();
1206ip6_route_fail:
1207#ifdef CONFIG_PROC_FS
1208        if6_proc_exit();
1209proc_if6_fail:
1210        ipv6_misc_proc_exit();
1211proc_misc6_fail:
1212        udplite6_proc_exit();
1213proc_udplite6_fail:
1214        raw6_proc_exit();
1215proc_raw6_fail:
1216#endif
1217        ipv6_netfilter_fini();
1218netfilter_fail:
1219        igmp6_cleanup();
1220igmp_fail:
1221        ndisc_cleanup();
1222ndisc_fail:
1223        ip6_mr_cleanup();
1224ipmr_fail:
1225        icmpv6_cleanup();
1226icmp_fail:
1227        unregister_pernet_subsys(&inet6_net_ops);
1228register_pernet_fail:
1229        sock_unregister(PF_INET6);
1230        rtnl_unregister_all(PF_INET6);
1231out_sock_register_fail:
1232        rawv6_exit();
1233out_unregister_raw_proto:
1234        proto_unregister(&rawv6_prot);
1235out_unregister_udplite_proto:
1236        proto_unregister(&udplitev6_prot);
1237out_unregister_udp_proto:
1238        proto_unregister(&udpv6_prot);
1239out_unregister_tcp_proto:
1240        proto_unregister(&tcpv6_prot);
1241        goto out;
1242}
1243module_init(inet6_init);
1244
1245static void __exit inet6_exit(void)
1246{
1247        if (disable_ipv6_mod)
1248                return;
1249
1250        /* First of all disallow new sockets creation. */
1251        sock_unregister(PF_INET6);
1252        /* Disallow any further netlink messages */
1253        rtnl_unregister_all(PF_INET6);
1254
1255        udpv6_exit();
1256        udplitev6_exit();
1257        tcpv6_exit();
1258
1259        /* Cleanup code parts. */
1260        ipv6_packet_cleanup();
1261        ipv6_frag_exit();
1262        ipv6_exthdrs_exit();
1263        addrconf_cleanup();
1264        ip6_flowlabel_cleanup();
1265        ip6_route_cleanup();
1266#ifdef CONFIG_PROC_FS
1267
1268        /* Cleanup code parts. */
1269        if6_proc_exit();
1270        ipv6_misc_proc_exit();
1271        udplite6_proc_exit();
1272        raw6_proc_exit();
1273#endif
1274        ipv6_netfilter_fini();
1275        igmp6_cleanup();
1276        ndisc_cleanup();
1277        ip6_mr_cleanup();
1278        icmpv6_cleanup();
1279        rawv6_exit();
1280
1281        unregister_pernet_subsys(&inet6_net_ops);
1282        proto_unregister(&rawv6_prot);
1283        proto_unregister(&udplitev6_prot);
1284        proto_unregister(&udpv6_prot);
1285        proto_unregister(&tcpv6_prot);
1286
1287        rcu_barrier(); /* Wait for completion of call_rcu()'s */
1288}
1289module_exit(inet6_exit);
1290
1291MODULE_ALIAS_NETPROTO(PF_INET6);
1292