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
  22 #include <linux/module.h>
  23 #include <linux/capability.h>
  24 #include <linux/errno.h>
  25 #include <linux/types.h>
  26 #include <linux/socket.h>
  27 #include <linux/in.h>
  28 #include <linux/kernel.h>
  29 #include <linux/timer.h>
  30 #include <linux/string.h>
  31 #include <linux/sockios.h>
  32 #include <linux/net.h>
  33 #include <linux/fcntl.h>
  34 #include <linux/mm.h>
  35 #include <linux/interrupt.h>
  36 #include <linux/proc_fs.h>
  37 #include <linux/stat.h>
  38 #include <linux/init.h>
  39 #include <linux/slab.h>
  40
  41 #include <linux/inet.h>
  42 #include <linux/netdevice.h>
  43 #include <linux/icmpv6.h>
  44 #include <linux/netfilter_ipv6.h>
  45
  46 #include <net/ip.h>
  47 #include <net/ipv6.h>
  48 #include <net/udp.h>
  49 #include <net/udplite.h>
  50 #include <net/tcp.h>
  51 #include <net/ipip.h>
  52 #include <net/protocol.h>
  53 #include <net/inet_common.h>
  54 #include <net/route.h>
  55 #include <net/transp_v6.h>
  56 #include <net/ip6_route.h>
  57 #include <net/addrconf.h>
  58 #ifdef CONFIG_IPV6_TUNNEL
  59 #include <net/ip6_tunnel.h>
  60 #endif
  61
  62 #include <asm/uaccess.h>
  63 #include <asm/system.h>
  64 #include <linux/mroute6.h>
  65
  66 MODULE_AUTHOR("Cast of dozens");
  67 MODULE_DESCRIPTION("IPv6 protocol stack for Linux");
  68 MODULE_LICENSE("GPL");
  69
  70 /* The inetsw6 table contains everything that inet6_create needs to
  71  * build a new socket.
  72  */
  73 static struct list_head inetsw6[SOCK_MAX];
  74 static DEFINE_SPINLOCK(inetsw6_lock);
  75
  76 struct ipv6_params ipv6_defaults = {
  77         .disable_ipv6 = 0,
  78         .autoconf = 1,
  79 };
  80
  81 static int disable_ipv6_mod = 0;
  82
  83 module_param_named(disable, disable_ipv6_mod, int, 0444);
  84 MODULE_PARM_DESC(disable, "Disable IPv6 module such that it is non-functional");
  85
  86 module_param_named(disable_ipv6, ipv6_defaults.disable_ipv6, int, 0444);
  87 MODULE_PARM_DESC(disable_ipv6, "Disable IPv6 on all interfaces");
  88
  89 module_param_named(autoconf, ipv6_defaults.autoconf, int, 0444);
  90 MODULE_PARM_DESC(autoconf, "Enable IPv6 address autoconfiguration on all interfaces");
  91
  92 static __inline__ struct ipv6_pinfo *inet6_sk_generic(struct sock *sk)
  93 {
  94         const int offset = sk->sk_prot->obj_size - sizeof(struct ipv6_pinfo);
  95
  96         return (struct ipv6_pinfo *)(((u8 *)sk) + offset);
  97 }
  98
  99 static int inet6_create(struct net *net, struct socket *sock, int protocol,
 100                         int kern)
 101 {
 102         struct inet_sock *inet;
 103         struct ipv6_pinfo *np;
 104         struct sock *sk;
 105         struct inet_protosw *answer;
 106         struct proto *answer_prot;
 107         unsigned char answer_flags;
 108         char answer_no_check;
 109         int try_loading_module = 0;
 110         int err;
 111
 112         if (sock->type != SOCK_RAW &&
 113             sock->type != SOCK_DGRAM &&
 114             !inet_ehash_secret)
 115                 build_ehash_secret();
 116
 117         /* Look for the requested type/protocol pair. */
 118 lookup_protocol:
 119         err = -ESOCKTNOSUPPORT;
 120         rcu_read_lock();
 121         list_for_each_entry_rcu(answer, &inetsw6[sock->type], list) {
 122
 123                 err = 0;
 124                 /* Check the non-wild match. */
 125                 if (protocol == answer->protocol) {
 126                         if (protocol != IPPROTO_IP)
 127                                 break;
 128                 } else {
 129                         /* Check for the two wild cases. */
 130                         if (IPPROTO_IP == protocol) {
 131                                 protocol = answer->protocol;
 132                                 break;
 133                         }
 134                         if (IPPROTO_IP == answer->protocol)
 135                                 break;
 136                 }
 137                 err = -EPROTONOSUPPORT;
 138         }
 139
 140         if (err) {
 141                 if (try_loading_module < 2) {
 142                         rcu_read_unlock();
 143                         /*
 144                          * Be more specific, e.g. net-pf-10-proto-132-type-1
 145                          * (net-pf-PF_INET6-proto-IPPROTO_SCTP-type-SOCK_STREAM)
 146                          */
 147                         if (++try_loading_module == 1)
 148                                 request_module("net-pf-%d-proto-%d-type-%d",
 149                                                 PF_INET6, protocol, sock->type);
 150                         /*
 151                          * Fall back to generic, e.g. net-pf-10-proto-132
 152                          * (net-pf-PF_INET6-proto-IPPROTO_SCTP)
 153                          */
 154                         else
 155                                 request_module("net-pf-%d-proto-%d",
 156                                                 PF_INET6, protocol);
 157                         goto lookup_protocol;
 158                 } else
 159                         goto out_rcu_unlock;
 160         }
 161
 162         err = -EPERM;
 163         if (sock->type == SOCK_RAW && !kern && !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 = 1;
 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
 218         if (ipv4_config.no_pmtu_disc)
 219                 inet->pmtudisc = IP_PMTUDISC_DONT;
 220         else
 221                 inet->pmtudisc = IP_PMTUDISC_WANT;
 222         /*
 223          * Increment only the relevant sk_prot->socks debug field, this changes
 224          * the previous behaviour of incrementing both the equivalent to
 225          * answer->prot->socks (inet6_sock_nr) and inet_sock_nr.
 226          *
 227          * This allows better debug granularity as we'll know exactly how many
 228          * UDPv6, TCPv6, etc socks were allocated, not the sum of all IPv6
 229          * transport protocol socks. -acme
 230          */
 231         sk_refcnt_debug_inc(sk);
 232
 233         if (inet->inet_num) {
 234                 /* It assumes that any protocol which allows
 235                  * the user to assign a number at socket
 236                  * creation time automatically shares.
 237                  */
 238                 inet->inet_sport = htons(inet->inet_num);
 239                 sk->sk_prot->hash(sk);
 240         }
 241         if (sk->sk_prot->init) {
 242                 err = sk->sk_prot->init(sk);
 243                 if (err) {
 244                         sk_common_release(sk);
 245                         goto out;
 246                 }
 247         }
 248 out:
 249         return err;
 250 out_rcu_unlock:
 251         rcu_read_unlock();
 252         goto out;
 253 }
 254
 255
 256 /* bind for INET6 API */
 257 int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 258 {
 259         struct sockaddr_in6 *addr=(struct sockaddr_in6 *)uaddr;
 260         struct sock *sk = sock->sk;
 261         struct inet_sock *inet = inet_sk(sk);
 262         struct ipv6_pinfo *np = inet6_sk(sk);
 263         struct net *net = sock_net(sk);
 264         __be32 v4addr = 0;
 265         unsigned short snum;
 266         int addr_type = 0;
 267         int err = 0;
 268
 269         /* If the socket has its own bind function then use it. */
 270         if (sk->sk_prot->bind)
 271                 return sk->sk_prot->bind(sk, uaddr, addr_len);
 272
 273         if (addr_len < SIN6_LEN_RFC2133)
 274                 return -EINVAL;
 275         addr_type = ipv6_addr_type(&addr->sin6_addr);
 276         if ((addr_type & IPV6_ADDR_MULTICAST) && sock->type == SOCK_STREAM)
 277                 return -EINVAL;
 278
 279         snum = ntohs(addr->sin6_port);
 280         if (snum && snum < PROT_SOCK && !capable(CAP_NET_BIND_SERVICE))
 281                 return -EACCES;
 282
 283         lock_sock(sk);
 284
 285         /* Check these errors (active socket, double bind). */
 286         if (sk->sk_state != TCP_CLOSE || inet->inet_num) {
 287                 err = -EINVAL;
 288                 goto out;
 289         }
 290
 291         /* Check if the address belongs to the host. */
 292         if (addr_type == IPV6_ADDR_MAPPED) {
 293                 int chk_addr_ret;
 294
 295                 /* Binding to v4-mapped address on a v6-only socket
 296                  * makes no sense
 297                  */
 298                 if (np->ipv6only) {
 299                         err = -EINVAL;
 300                         goto out;
 301                 }
 302
 303                 /* Reproduce AF_INET checks to make the bindings consistent */
 304                 v4addr = addr->sin6_addr.s6_addr32[3];
 305                 chk_addr_ret = inet_addr_type(net, v4addr);
 306                 if (!sysctl_ip_nonlocal_bind &&
 307                     !(inet->freebind || inet->transparent) &&
 308                     v4addr != htonl(INADDR_ANY) &&
 309                     chk_addr_ret != RTN_LOCAL &&
 310                     chk_addr_ret != RTN_MULTICAST &&
 311                     chk_addr_ret != RTN_BROADCAST) {
 312                         err = -EADDRNOTAVAIL;
 313                         goto out;
 314                 }
 315         } else {
 316                 if (addr_type != IPV6_ADDR_ANY) {
 317                         struct net_device *dev = NULL;
 318
 319                         rcu_read_lock();
 320                         if (addr_type & IPV6_ADDR_LINKLOCAL) {
 321                                 if (addr_len >= sizeof(struct sockaddr_in6) &&
 322                                     addr->sin6_scope_id) {
 323                                         /* Override any existing binding, if another one
 324                                          * is supplied by user.
 325                                          */
 326                                         sk->sk_bound_dev_if = addr->sin6_scope_id;
 327                                 }
 328
 329                                 /* Binding to link-local address requires an interface */
 330                                 if (!sk->sk_bound_dev_if) {
 331                                         err = -EINVAL;
 332                                         goto out_unlock;
 333                                 }
 334                                 dev = dev_get_by_index_rcu(net, sk->sk_bound_dev_if);
 335                                 if (!dev) {
 336                                         err = -ENODEV;
 337                                         goto out_unlock;
 338                                 }
 339                         }
 340
 341                         /* ipv4 addr of the socket is invalid.  Only the
 342                          * unspecified and mapped address have a v4 equivalent.
 343                          */
 344                         v4addr = LOOPBACK4_IPV6;
 345                         if (!(addr_type & IPV6_ADDR_MULTICAST)) {
 346                                 if (!inet->transparent &&
 347                                     !ipv6_chk_addr(net, &addr->sin6_addr,
 348                                                    dev, 0)) {
 349                                         err = -EADDRNOTAVAIL;
 350                                         goto out_unlock;
 351                                 }
 352                         }
 353                         rcu_read_unlock();
 354                 }
 355         }
 356
 357         inet->inet_rcv_saddr = v4addr;
 358         inet->inet_saddr = v4addr;
 359
 360         ipv6_addr_copy(&np->rcv_saddr, &addr->sin6_addr);
 361
 362         if (!(addr_type & IPV6_ADDR_MULTICAST))
 363                 ipv6_addr_copy(&np->saddr, &addr->sin6_addr);
 364
 365         /* Make sure we are allowed to bind here. */
 366         if (sk->sk_prot->get_port(sk, snum)) {
 367                 inet_reset_saddr(sk);
 368                 err = -EADDRINUSE;
 369                 goto out;
 370         }
 371
 372         if (addr_type != IPV6_ADDR_ANY) {
 373                 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
 374                 if (addr_type != IPV6_ADDR_MAPPED)
 375                         np->ipv6only = 1;
 376         }
 377         if (snum)
 378                 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
 379         inet->inet_sport = htons(inet->inet_num);
 380         inet->inet_dport = 0;
 381         inet->inet_daddr = 0;
 382 out:
 383         release_sock(sk);
 384         return err;
 385 out_unlock:
 386         rcu_read_unlock();
 387         goto out;
 388 }
 389
 390 EXPORT_SYMBOL(inet6_bind);
 391
 392 int inet6_release(struct socket *sock)
 393 {
 394         struct sock *sk = sock->sk;
 395
 396         if (sk == NULL)
 397                 return -EINVAL;
 398
 399         /* Free mc lists */
 400         ipv6_sock_mc_close(sk);
 401
 402         /* Free ac lists */
 403         ipv6_sock_ac_close(sk);
 404
 405         return inet_release(sock);
 406 }
 407
 408 EXPORT_SYMBOL(inet6_release);
 409
 410 void inet6_destroy_sock(struct sock *sk)
 411 {
 412         struct ipv6_pinfo *np = inet6_sk(sk);
 413         struct sk_buff *skb;
 414         struct ipv6_txoptions *opt;
 415
 416         /* Release rx options */
 417
 418         if ((skb = xchg(&np->pktoptions, NULL)) != NULL)
 419                 kfree_skb(skb);
 420
 421         if ((skb = xchg(&np->rxpmtu, NULL)) != NULL)
 422                 kfree_skb(skb);
 423
 424         /* Free flowlabels */
 425         fl6_free_socklist(sk);
 426
 427         /* Free tx options */
 428
 429         if ((opt = xchg(&np->opt, NULL)) != NULL)
 430                 sock_kfree_s(sk, opt, opt->tot_len);
 431 }
 432
 433 EXPORT_SYMBOL_GPL(inet6_destroy_sock);
 434
 435 /*
 436  *      This does both peername and sockname.
 437  */
 438
 439 int inet6_getname(struct socket *sock, struct sockaddr *uaddr,
 440                  int *uaddr_len, int peer)
 441 {
 442         struct sockaddr_in6 *sin=(struct sockaddr_in6 *)uaddr;
 443         struct sock *sk = sock->sk;
 444         struct inet_sock *inet = inet_sk(sk);
 445         struct ipv6_pinfo *np = inet6_sk(sk);
 446
 447         sin->sin6_family = AF_INET6;
 448         sin->sin6_flowinfo = 0;
 449         sin->sin6_scope_id = 0;
 450         if (peer) {
 451                 if (!inet->inet_dport)
 452                         return -ENOTCONN;
 453                 if (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
 454                     peer == 1)
 455                         return -ENOTCONN;
 456                 sin->sin6_port = inet->inet_dport;
 457                 ipv6_addr_copy(&sin->sin6_addr, &np->daddr);
 458                 if (np->sndflow)
 459                         sin->sin6_flowinfo = np->flow_label;
 460         } else {
 461                 if (ipv6_addr_any(&np->rcv_saddr))
 462                         ipv6_addr_copy(&sin->sin6_addr, &np->saddr);
 463                 else
 464                         ipv6_addr_copy(&sin->sin6_addr, &np->rcv_saddr);
 465
 466                 sin->sin6_port = inet->inet_sport;
 467         }
 468         if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
 469                 sin->sin6_scope_id = sk->sk_bound_dev_if;
 470         *uaddr_len = sizeof(*sin);
 471         return 0;
 472 }
 473
 474 EXPORT_SYMBOL(inet6_getname);
 475
 476 int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
 477 {
 478         struct sock *sk = sock->sk;
 479         struct net *net = sock_net(sk);
 480
 481         switch(cmd)
 482         {
 483         case SIOCGSTAMP:
 484                 return sock_get_timestamp(sk, (struct timeval __user *)arg);
 485
 486         case SIOCGSTAMPNS:
 487                 return sock_get_timestampns(sk, (struct timespec __user *)arg);
 488
 489         case SIOCADDRT:
 490         case SIOCDELRT:
 491
 492                 return ipv6_route_ioctl(net, cmd, (void __user *)arg);
 493
 494         case SIOCSIFADDR:
 495                 return addrconf_add_ifaddr(net, (void __user *) arg);
 496         case SIOCDIFADDR:
 497                 return addrconf_del_ifaddr(net, (void __user *) arg);
 498         case SIOCSIFDSTADDR:
 499                 return addrconf_set_dstaddr(net, (void __user *) arg);
 500         default:
 501                 if (!sk->sk_prot->ioctl)
 502                         return -ENOIOCTLCMD;
 503                 return sk->sk_prot->ioctl(sk, cmd, arg);
 504         }
 505         /*NOTREACHED*/
 506         return 0;
 507 }
 508
 509 EXPORT_SYMBOL(inet6_ioctl);
 510
 511 const struct proto_ops inet6_stream_ops = {
 512         .family            = PF_INET6,
 513         .owner             = THIS_MODULE,
 514         .release           = inet6_release,
 515         .bind              = inet6_bind,
 516         .connect           = inet_stream_connect,       /* ok           */
 517         .socketpair        = sock_no_socketpair,        /* a do nothing */
 518         .accept            = inet_accept,               /* ok           */
 519         .getname           = inet6_getname,
 520         .poll              = tcp_poll,                  /* ok           */
 521         .ioctl             = inet6_ioctl,               /* must change  */
 522         .listen            = inet_listen,               /* ok           */
 523         .shutdown          = inet_shutdown,             /* ok           */
 524         .setsockopt        = sock_common_setsockopt,    /* ok           */
 525         .getsockopt        = sock_common_getsockopt,    /* ok           */
 526         .sendmsg           = inet_sendmsg,              /* ok           */
 527         .recvmsg           = inet_recvmsg,              /* ok           */
 528         .mmap              = sock_no_mmap,
 529         .sendpage          = inet_sendpage,
 530         .splice_read       = tcp_splice_read,
 531 #ifdef CONFIG_COMPAT
 532         .compat_setsockopt = compat_sock_common_setsockopt,
 533         .compat_getsockopt = compat_sock_common_getsockopt,
 534 #endif
 535 };
 536
 537 const struct proto_ops inet6_dgram_ops = {
 538         .family            = PF_INET6,
 539         .owner             = THIS_MODULE,
 540         .release           = inet6_release,
 541         .bind              = inet6_bind,
 542         .connect           = inet_dgram_connect,        /* ok           */
 543         .socketpair        = sock_no_socketpair,        /* a do nothing */
 544         .accept            = sock_no_accept,            /* a do nothing */
 545         .getname           = inet6_getname,
 546         .poll              = udp_poll,                  /* ok           */
 547         .ioctl             = inet6_ioctl,               /* must change  */
 548         .listen            = sock_no_listen,            /* ok           */
 549         .shutdown          = inet_shutdown,             /* ok           */
 550         .setsockopt        = sock_common_setsockopt,    /* ok           */
 551         .getsockopt        = sock_common_getsockopt,    /* ok           */
 552         .sendmsg           = inet_sendmsg,              /* ok           */
 553         .recvmsg           = inet_recvmsg,              /* ok           */
 554         .mmap              = sock_no_mmap,
 555         .sendpage          = sock_no_sendpage,
 556 #ifdef CONFIG_COMPAT
 557         .compat_setsockopt = compat_sock_common_setsockopt,
 558         .compat_getsockopt = compat_sock_common_getsockopt,
 559 #endif
 560 };
 561
 562 static const struct net_proto_family inet6_family_ops = {
 563         .family = PF_INET6,
 564         .create = inet6_create,
 565         .owner  = THIS_MODULE,
 566 };
 567
 568 int inet6_register_protosw(struct inet_protosw *p)
 569 {
 570         struct list_head *lh;
 571         struct inet_protosw *answer;
 572         struct list_head *last_perm;
 573         int protocol = p->protocol;
 574         int ret;
 575
 576         spin_lock_bh(&inetsw6_lock);
 577
 578         ret = -EINVAL;
 579         if (p->type >= SOCK_MAX)
 580                 goto out_illegal;
 581
 582         /* If we are trying to override a permanent protocol, bail. */
 583         answer = NULL;
 584         ret = -EPERM;
 585         last_perm = &inetsw6[p->type];
 586         list_for_each(lh, &inetsw6[p->type]) {
 587                 answer = list_entry(lh, struct inet_protosw, list);
 588
 589                 /* Check only the non-wild match. */
 590                 if (INET_PROTOSW_PERMANENT & answer->flags) {
 591                         if (protocol == answer->protocol)
 592                                 break;
 593                         last_perm = lh;
 594                 }
 595
 596                 answer = NULL;
 597         }
 598         if (answer)
 599                 goto out_permanent;
 600
 601         /* Add the new entry after the last permanent entry if any, so that
 602          * the new entry does not override a permanent entry when matched with
 603          * a wild-card protocol. But it is allowed to override any existing
 604          * non-permanent entry.  This means that when we remove this entry, the
 605          * system automatically returns to the old behavior.
 606          */
 607         list_add_rcu(&p->list, last_perm);
 608         ret = 0;
 609 out:
 610         spin_unlock_bh(&inetsw6_lock);
 611         return ret;
 612
 613 out_permanent:
 614         printk(KERN_ERR "Attempt to override permanent protocol %d.\n",
 615                protocol);
 616         goto out;
 617
 618 out_illegal:
 619         printk(KERN_ERR
 620                "Ignoring attempt to register invalid socket type %d.\n",
 621                p->type);
 622         goto out;
 623 }
 624
 625 EXPORT_SYMBOL(inet6_register_protosw);
 626
 627 void
 628 inet6_unregister_protosw(struct inet_protosw *p)
 629 {
 630         if (INET_PROTOSW_PERMANENT & p->flags) {
 631                 printk(KERN_ERR
 632                        "Attempt to unregister permanent protocol %d.\n",
 633                        p->protocol);
 634         } else {
 635                 spin_lock_bh(&inetsw6_lock);
 636                 list_del_rcu(&p->list);
 637                 spin_unlock_bh(&inetsw6_lock);
 638
 639                 synchronize_net();
 640         }
 641 }
 642
 643 EXPORT_SYMBOL(inet6_unregister_protosw);
 644
 645 int inet6_sk_rebuild_header(struct sock *sk)
 646 {
 647         struct ipv6_pinfo *np = inet6_sk(sk);
 648         struct dst_entry *dst;
 649
 650         dst = __sk_dst_check(sk, np->dst_cookie);
 651
 652         if (dst == NULL) {
 653                 struct inet_sock *inet = inet_sk(sk);
 654                 struct in6_addr *final_p, final;
 655                 struct flowi6 fl6;
 656
 657                 memset(&fl6, 0, sizeof(fl6));
 658                 fl6.flowi6_proto = sk->sk_protocol;
 659                 ipv6_addr_copy(&fl6.daddr, &np->daddr);
 660                 ipv6_addr_copy(&fl6.saddr, &np->saddr);
 661                 fl6.flowlabel = np->flow_label;
 662                 fl6.flowi6_oif = sk->sk_bound_dev_if;
 663                 fl6.flowi6_mark = sk->sk_mark;
 664                 fl6.fl6_dport = inet->inet_dport;
 665                 fl6.fl6_sport = inet->inet_sport;
 666                 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
 667
 668                 final_p = fl6_update_dst(&fl6, np->opt, &final);
 669
 670                 dst = ip6_dst_lookup_flow(sk, &fl6, final_p, false);
 671                 if (IS_ERR(dst)) {
 672                         sk->sk_route_caps = 0;
 673                         sk->sk_err_soft = -PTR_ERR(dst);
 674                         return PTR_ERR(dst);
 675                 }
 676
 677                 __ip6_dst_store(sk, dst, NULL, NULL);
 678         }
 679
 680         return 0;
 681 }
 682
 683 EXPORT_SYMBOL_GPL(inet6_sk_rebuild_header);
 684
 685 int ipv6_opt_accepted(struct sock *sk, struct sk_buff *skb)
 686 {
 687         struct ipv6_pinfo *np = inet6_sk(sk);
 688         struct inet6_skb_parm *opt = IP6CB(skb);
 689
 690         if (np->rxopt.all) {
 691                 if ((opt->hop && (np->rxopt.bits.hopopts ||
 692                                   np->rxopt.bits.ohopopts)) ||
 693                     ((IPV6_FLOWINFO_MASK &
 694                       *(__be32 *)skb_network_header(skb)) &&
 695                      np->rxopt.bits.rxflow) ||
 696                     (opt->srcrt && (np->rxopt.bits.srcrt ||
 697                      np->rxopt.bits.osrcrt)) ||
 698                     ((opt->dst1 || opt->dst0) &&
 699                      (np->rxopt.bits.dstopts || np->rxopt.bits.odstopts)))
 700                         return 1;
 701         }
 702         return 0;
 703 }
 704
 705 EXPORT_SYMBOL_GPL(ipv6_opt_accepted);
 706
 707 static int ipv6_gso_pull_exthdrs(struct sk_buff *skb, int proto)
 708 {
 709         const struct inet6_protocol *ops = NULL;
 710
 711         for (;;) {
 712                 struct ipv6_opt_hdr *opth;
 713                 int len;
 714
 715                 if (proto != NEXTHDR_HOP) {
 716                         ops = rcu_dereference(inet6_protos[proto]);
 717
 718                         if (unlikely(!ops))
 719                                 break;
 720
 721                         if (!(ops->flags & INET6_PROTO_GSO_EXTHDR))
 722                                 break;
 723                 }
 724
 725                 if (unlikely(!pskb_may_pull(skb, 8)))
 726                         break;
 727
 728                 opth = (void *)skb->data;
 729                 len = ipv6_optlen(opth);
 730
 731                 if (unlikely(!pskb_may_pull(skb, len)))
 732                         break;
 733
 734                 proto = opth->nexthdr;
 735                 __skb_pull(skb, len);
 736         }
 737
 738         return proto;
 739 }
 740
 741 static int ipv6_gso_send_check(struct sk_buff *skb)
 742 {
 743         const struct ipv6hdr *ipv6h;
 744         const struct inet6_protocol *ops;
 745         int err = -EINVAL;
 746
 747         if (unlikely(!pskb_may_pull(skb, sizeof(*ipv6h))))
 748                 goto out;
 749
 750         ipv6h = ipv6_hdr(skb);
 751         __skb_pull(skb, sizeof(*ipv6h));
 752         err = -EPROTONOSUPPORT;
 753
 754         rcu_read_lock();
 755         ops = rcu_dereference(inet6_protos[
 756                 ipv6_gso_pull_exthdrs(skb, ipv6h->nexthdr)]);
 757
 758         if (likely(ops && ops->gso_send_check)) {
 759                 skb_reset_transport_header(skb);
 760                 err = ops->gso_send_check(skb);
 761         }
 762         rcu_read_unlock();
 763
 764 out:
 765         return err;
 766 }
 767
 768 static struct sk_buff *ipv6_gso_segment(struct sk_buff *skb, u32 features)
 769 {
 770         struct sk_buff *segs = ERR_PTR(-EINVAL);
 771         struct ipv6hdr *ipv6h;
 772         const struct inet6_protocol *ops;
 773         int proto;
 774         struct frag_hdr *fptr;
 775         unsigned int unfrag_ip6hlen;
 776         u8 *prevhdr;
 777         int offset = 0;
 778
 779         if (!(features & NETIF_F_V6_CSUM))
 780                 features &= ~NETIF_F_SG;
 781
 782         if (unlikely(skb_shinfo(skb)->gso_type &
 783                      ~(SKB_GSO_UDP |
 784                        SKB_GSO_DODGY |
 785                        SKB_GSO_TCP_ECN |
 786                        SKB_GSO_TCPV6 |
 787                        0)))
 788                 goto out;
 789
 790         if (unlikely(!pskb_may_pull(skb, sizeof(*ipv6h))))
 791                 goto out;
 792
 793         ipv6h = ipv6_hdr(skb);
 794         __skb_pull(skb, sizeof(*ipv6h));
 795         segs = ERR_PTR(-EPROTONOSUPPORT);
 796
 797         proto = ipv6_gso_pull_exthdrs(skb, ipv6h->nexthdr);
 798         rcu_read_lock();
 799         ops = rcu_dereference(inet6_protos[proto]);
 800         if (likely(ops && ops->gso_segment)) {
 801                 skb_reset_transport_header(skb);
 802                 segs = ops->gso_segment(skb, features);
 803         }
 804         rcu_read_unlock();
 805
 806         if (IS_ERR(segs))
 807                 goto out;
 808
 809         for (skb = segs; skb; skb = skb->next) {
 810                 ipv6h = ipv6_hdr(skb);
 811                 ipv6h->payload_len = htons(skb->len - skb->mac_len -
 812                                            sizeof(*ipv6h));
 813                 if (proto == IPPROTO_UDP) {
 814                         unfrag_ip6hlen = ip6_find_1stfragopt(skb, &prevhdr);
 815                         fptr = (struct frag_hdr *)(skb_network_header(skb) +
 816                                 unfrag_ip6hlen);
 817                         fptr->frag_off = htons(offset);
 818                         if (skb->next != NULL)
 819                                 fptr->frag_off |= htons(IP6_MF);
 820                         offset += (ntohs(ipv6h->payload_len) -
 821                                    sizeof(struct frag_hdr));
 822                 }
 823         }
 824
 825 out:
 826         return segs;
 827 }
 828
 829 struct ipv6_gro_cb {
 830         struct napi_gro_cb napi;
 831         int proto;
 832 };
 833
 834 #define IPV6_GRO_CB(skb) ((struct ipv6_gro_cb *)(skb)->cb)
 835
 836 static struct sk_buff **ipv6_gro_receive(struct sk_buff **head,
 837                                          struct sk_buff *skb)
 838 {
 839         const struct inet6_protocol *ops;
 840         struct sk_buff **pp = NULL;
 841         struct sk_buff *p;
 842         struct ipv6hdr *iph;
 843         unsigned int nlen;
 844         unsigned int hlen;
 845         unsigned int off;
 846         int flush = 1;
 847         int proto;
 848         __wsum csum;
 849
 850         off = skb_gro_offset(skb);
 851         hlen = off + sizeof(*iph);
 852         iph = skb_gro_header_fast(skb, off);
 853         if (skb_gro_header_hard(skb, hlen)) {
 854                 iph = skb_gro_header_slow(skb, hlen, off);
 855                 if (unlikely(!iph))
 856                         goto out;
 857         }
 858
 859         skb_gro_pull(skb, sizeof(*iph));
 860         skb_set_transport_header(skb, skb_gro_offset(skb));
 861
 862         flush += ntohs(iph->payload_len) != skb_gro_len(skb);
 863
 864         rcu_read_lock();
 865         proto = iph->nexthdr;
 866         ops = rcu_dereference(inet6_protos[proto]);
 867         if (!ops || !ops->gro_receive) {
 868                 __pskb_pull(skb, skb_gro_offset(skb));
 869                 proto = ipv6_gso_pull_exthdrs(skb, proto);
 870                 skb_gro_pull(skb, -skb_transport_offset(skb));
 871                 skb_reset_transport_header(skb);
 872                 __skb_push(skb, skb_gro_offset(skb));
 873
 874                 if (!ops || !ops->gro_receive)
 875                         goto out_unlock;
 876
 877                 iph = ipv6_hdr(skb);
 878         }
 879
 880         IPV6_GRO_CB(skb)->proto = proto;
 881
 882         flush--;
 883         nlen = skb_network_header_len(skb);
 884
 885         for (p = *head; p; p = p->next) {
 886                 struct ipv6hdr *iph2;
 887
 888                 if (!NAPI_GRO_CB(p)->same_flow)
 889                         continue;
 890
 891                 iph2 = ipv6_hdr(p);
 892
 893                 /* All fields must match except length. */
 894                 if (nlen != skb_network_header_len(p) ||
 895                     memcmp(iph, iph2, offsetof(struct ipv6hdr, payload_len)) ||
 896                     memcmp(&iph->nexthdr, &iph2->nexthdr,
 897                            nlen - offsetof(struct ipv6hdr, nexthdr))) {
 898                         NAPI_GRO_CB(p)->same_flow = 0;
 899                         continue;
 900                 }
 901
 902                 NAPI_GRO_CB(p)->flush |= flush;
 903         }
 904
 905         NAPI_GRO_CB(skb)->flush |= flush;
 906
 907         csum = skb->csum;
 908         skb_postpull_rcsum(skb, iph, skb_network_header_len(skb));
 909
 910         pp = ops->gro_receive(head, skb);
 911
 912         skb->csum = csum;
 913
 914 out_unlock:
 915         rcu_read_unlock();
 916
 917 out:
 918         NAPI_GRO_CB(skb)->flush |= flush;
 919
 920         return pp;
 921 }
 922
 923 static int ipv6_gro_complete(struct sk_buff *skb)
 924 {
 925         const struct inet6_protocol *ops;
 926         struct ipv6hdr *iph = ipv6_hdr(skb);
 927         int err = -ENOSYS;
 928
 929         iph->payload_len = htons(skb->len - skb_network_offset(skb) -
 930                                  sizeof(*iph));
 931
 932         rcu_read_lock();
 933         ops = rcu_dereference(inet6_protos[IPV6_GRO_CB(skb)->proto]);
 934         if (WARN_ON(!ops || !ops->gro_complete))
 935                 goto out_unlock;
 936
 937         err = ops->gro_complete(skb);
 938
 939 out_unlock:
 940         rcu_read_unlock();
 941
 942         return err;
 943 }
 944
 945 static struct packet_type ipv6_packet_type __read_mostly = {
 946         .type = cpu_to_be16(ETH_P_IPV6),
 947         .func = ipv6_rcv,
 948         .gso_send_check = ipv6_gso_send_check,
 949         .gso_segment = ipv6_gso_segment,
 950         .gro_receive = ipv6_gro_receive,
 951         .gro_complete = ipv6_gro_complete,
 952 };
 953
 954 static int __init ipv6_packet_init(void)
 955 {
 956         dev_add_pack(&ipv6_packet_type);
 957         return 0;
 958 }
 959
 960 static void ipv6_packet_cleanup(void)
 961 {
 962         dev_remove_pack(&ipv6_packet_type);
 963 }
 964
 965 static int __net_init ipv6_init_mibs(struct net *net)
 966 {
 967         if (snmp_mib_init((void __percpu **)net->mib.udp_stats_in6,
 968                           sizeof(struct udp_mib),
 969                           __alignof__(struct udp_mib)) < 0)
 970                 return -ENOMEM;
 971         if (snmp_mib_init((void __percpu **)net->mib.udplite_stats_in6,
 972                           sizeof(struct udp_mib),
 973                           __alignof__(struct udp_mib)) < 0)
 974                 goto err_udplite_mib;
 975         if (snmp_mib_init((void __percpu **)net->mib.ipv6_statistics,
 976                           sizeof(struct ipstats_mib),
 977                           __alignof__(struct ipstats_mib)) < 0)
 978                 goto err_ip_mib;
 979         if (snmp_mib_init((void __percpu **)net->mib.icmpv6_statistics,
 980                           sizeof(struct icmpv6_mib),
 981                           __alignof__(struct icmpv6_mib)) < 0)
 982                 goto err_icmp_mib;
 983         if (snmp_mib_init((void __percpu **)net->mib.icmpv6msg_statistics,
 984                           sizeof(struct icmpv6msg_mib),
 985                           __alignof__(struct icmpv6msg_mib)) < 0)
 986                 goto err_icmpmsg_mib;
 987         return 0;
 988
 989 err_icmpmsg_mib:
 990         snmp_mib_free((void __percpu **)net->mib.icmpv6_statistics);
 991 err_icmp_mib:
 992         snmp_mib_free((void __percpu **)net->mib.ipv6_statistics);
 993 err_ip_mib:
 994         snmp_mib_free((void __percpu **)net->mib.udplite_stats_in6);
 995 err_udplite_mib:
 996         snmp_mib_free((void __percpu **)net->mib.udp_stats_in6);
 997         return -ENOMEM;
 998 }
 999
1000 static void ipv6_cleanup_mibs(struct net *net)
1001 {
1002         snmp_mib_free((void __percpu **)net->mib.udp_stats_in6);
1003         snmp_mib_free((void __percpu **)net->mib.udplite_stats_in6);
1004         snmp_mib_free((void __percpu **)net->mib.ipv6_statistics);
1005         snmp_mib_free((void __percpu **)net->mib.icmpv6_statistics);
1006         snmp_mib_free((void __percpu **)net->mib.icmpv6msg_statistics);
1007 }
1008
1009 static int __net_init inet6_net_init(struct net *net)
1010 {
1011         int err = 0;
1012
1013         net->ipv6.sysctl.bindv6only = 0;
1014         net->ipv6.sysctl.icmpv6_time = 1*HZ;
1015
1016         err = ipv6_init_mibs(net);
1017         if (err)
1018                 return err;
1019 #ifdef CONFIG_PROC_FS
1020         err = udp6_proc_init(net);
1021         if (err)
1022                 goto out;
1023         err = tcp6_proc_init(net);
1024         if (err)
1025                 goto proc_tcp6_fail;
1026         err = ac6_proc_init(net);
1027         if (err)
1028                 goto proc_ac6_fail;
1029 #endif
1030         return err;
1031
1032 #ifdef CONFIG_PROC_FS
1033 proc_ac6_fail:
1034         tcp6_proc_exit(net);
1035 proc_tcp6_fail:
1036         udp6_proc_exit(net);
1037 out:
1038         ipv6_cleanup_mibs(net);
1039         return err;
1040 #endif
1041 }
1042
1043 static void __net_exit inet6_net_exit(struct net *net)
1044 {
1045 #ifdef CONFIG_PROC_FS
1046         udp6_proc_exit(net);
1047         tcp6_proc_exit(net);
1048         ac6_proc_exit(net);
1049 #endif
1050         ipv6_cleanup_mibs(net);
1051 }
1052
1053 static struct pernet_operations inet6_net_ops = {
1054         .init = inet6_net_init,
1055         .exit = inet6_net_exit,
1056 };
1057
1058 static int __init inet6_init(void)
1059 {
1060         struct sk_buff *dummy_skb;
1061         struct list_head *r;
1062         int err = 0;
1063
1064         BUILD_BUG_ON(sizeof(struct inet6_skb_parm) > sizeof(dummy_skb->cb));
1065
1066         /* Register the socket-side information for inet6_create.  */
1067         for(r = &inetsw6[0]; r < &inetsw6[SOCK_MAX]; ++r)
1068                 INIT_LIST_HEAD(r);
1069
1070         if (disable_ipv6_mod) {
1071                 printk(KERN_INFO
1072                        "IPv6: Loaded, but administratively disabled, "
1073                        "reboot required to enable\n");
1074                 goto out;
1075         }
1076
1077         err = proto_register(&tcpv6_prot, 1);
1078         if (err)
1079                 goto out;
1080
1081         err = proto_register(&udpv6_prot, 1);
1082         if (err)
1083                 goto out_unregister_tcp_proto;
1084
1085         err = proto_register(&udplitev6_prot, 1);
1086         if (err)
1087                 goto out_unregister_udp_proto;
1088
1089         err = proto_register(&rawv6_prot, 1);
1090         if (err)
1091                 goto out_unregister_udplite_proto;
1092
1093
1094         /* We MUST register RAW sockets before we create the ICMP6,
1095          * IGMP6, or NDISC control sockets.
1096          */
1097         err = rawv6_init();
1098         if (err)
1099                 goto out_unregister_raw_proto;
1100
1101         /* Register the family here so that the init calls below will
1102          * be able to create sockets. (?? is this dangerous ??)
1103          */
1104         err = sock_register(&inet6_family_ops);
1105         if (err)
1106                 goto out_sock_register_fail;
1107
1108 #ifdef CONFIG_SYSCTL
1109         err = ipv6_static_sysctl_register();
1110         if (err)
1111                 goto static_sysctl_fail;
1112 #endif
1113         /*
1114          *      ipngwg API draft makes clear that the correct semantics
1115          *      for TCP and UDP is to consider one TCP and UDP instance
1116          *      in a host available by both INET and INET6 APIs and
1117          *      able to communicate via both network protocols.
1118          */
1119
1120         err = register_pernet_subsys(&inet6_net_ops);
1121         if (err)
1122                 goto register_pernet_fail;
1123         err = icmpv6_init();
1124         if (err)
1125                 goto icmp_fail;
1126         err = ip6_mr_init();
1127         if (err)
1128                 goto ipmr_fail;
1129         err = ndisc_init();
1130         if (err)
1131                 goto ndisc_fail;
1132         err = igmp6_init();
1133         if (err)
1134                 goto igmp_fail;
1135         err = ipv6_netfilter_init();
1136         if (err)
1137                 goto netfilter_fail;
1138         /* Create /proc/foo6 entries. */
1139 #ifdef CONFIG_PROC_FS
1140         err = -ENOMEM;
1141         if (raw6_proc_init())
1142                 goto proc_raw6_fail;
1143         if (udplite6_proc_init())
1144                 goto proc_udplite6_fail;
1145         if (ipv6_misc_proc_init())
1146                 goto proc_misc6_fail;
1147         if (if6_proc_init())
1148                 goto proc_if6_fail;
1149 #endif
1150         err = ip6_route_init();
1151         if (err)
1152                 goto ip6_route_fail;
1153         err = ip6_flowlabel_init();
1154         if (err)
1155                 goto ip6_flowlabel_fail;
1156         err = addrconf_init();
1157         if (err)
1158                 goto addrconf_fail;
1159
1160         /* Init v6 extension headers. */
1161         err = ipv6_exthdrs_init();
1162         if (err)
1163                 goto ipv6_exthdrs_fail;
1164
1165         err = ipv6_frag_init();
1166         if (err)
1167                 goto ipv6_frag_fail;
1168
1169         /* Init v6 transport protocols. */
1170         err = udpv6_init();
1171         if (err)
1172                 goto udpv6_fail;
1173
1174         err = udplitev6_init();
1175         if (err)
1176                 goto udplitev6_fail;
1177
1178         err = tcpv6_init();
1179         if (err)
1180                 goto tcpv6_fail;
1181
1182         err = ipv6_packet_init();
1183         if (err)
1184                 goto ipv6_packet_fail;
1185
1186 #ifdef CONFIG_SYSCTL
1187         err = ipv6_sysctl_register();
1188         if (err)
1189                 goto sysctl_fail;
1190 #endif
1191 out:
1192         return err;
1193
1194 #ifdef CONFIG_SYSCTL
1195 sysctl_fail:
1196         ipv6_packet_cleanup();
1197 #endif
1198 ipv6_packet_fail:
1199         tcpv6_exit();
1200 tcpv6_fail:
1201         udplitev6_exit();
1202 udplitev6_fail:
1203         udpv6_exit();
1204 udpv6_fail:
1205         ipv6_frag_exit();
1206 ipv6_frag_fail:
1207         ipv6_exthdrs_exit();
1208 ipv6_exthdrs_fail:
1209         addrconf_cleanup();
1210 addrconf_fail:
1211         ip6_flowlabel_cleanup();
1212 ip6_flowlabel_fail:
1213         ip6_route_cleanup();
1214 ip6_route_fail:
1215 #ifdef CONFIG_PROC_FS
1216         if6_proc_exit();
1217 proc_if6_fail:
1218         ipv6_misc_proc_exit();
1219 proc_misc6_fail:
1220         udplite6_proc_exit();
1221 proc_udplite6_fail:
1222         raw6_proc_exit();
1223 proc_raw6_fail:
1224 #endif
1225         ipv6_netfilter_fini();
1226 netfilter_fail:
1227         igmp6_cleanup();
1228 igmp_fail:
1229         ndisc_cleanup();
1230 ndisc_fail:
1231         ip6_mr_cleanup();
1232 ipmr_fail:
1233         icmpv6_cleanup();
1234 icmp_fail:
1235         unregister_pernet_subsys(&inet6_net_ops);
1236 register_pernet_fail:
1237 #ifdef CONFIG_SYSCTL
1238         ipv6_static_sysctl_unregister();
1239 static_sysctl_fail:
1240 #endif
1241         sock_unregister(PF_INET6);
1242         rtnl_unregister_all(PF_INET6);
1243 out_sock_register_fail:
1244         rawv6_exit();
1245 out_unregister_raw_proto:
1246         proto_unregister(&rawv6_prot);
1247 out_unregister_udplite_proto:
1248         proto_unregister(&udplitev6_prot);
1249 out_unregister_udp_proto:
1250         proto_unregister(&udpv6_prot);
1251 out_unregister_tcp_proto:
1252         proto_unregister(&tcpv6_prot);
1253         goto out;
1254 }
1255 module_init(inet6_init);
1256
1257 static void __exit inet6_exit(void)
1258 {
1259         if (disable_ipv6_mod)
1260                 return;
1261
1262         /* First of all disallow new sockets creation. */
1263         sock_unregister(PF_INET6);
1264         /* Disallow any further netlink messages */
1265         rtnl_unregister_all(PF_INET6);
1266
1267 #ifdef CONFIG_SYSCTL
1268         ipv6_sysctl_unregister();
1269 #endif
1270         udpv6_exit();
1271         udplitev6_exit();
1272         tcpv6_exit();
1273
1274         /* Cleanup code parts. */
1275         ipv6_packet_cleanup();
1276         ipv6_frag_exit();
1277         ipv6_exthdrs_exit();
1278         addrconf_cleanup();
1279         ip6_flowlabel_cleanup();
1280         ip6_route_cleanup();
1281 #ifdef CONFIG_PROC_FS
1282
1283         /* Cleanup code parts. */
1284         if6_proc_exit();
1285         ipv6_misc_proc_exit();
1286         udplite6_proc_exit();
1287         raw6_proc_exit();
1288 #endif
1289         ipv6_netfilter_fini();
1290         igmp6_cleanup();
1291         ndisc_cleanup();
1292         ip6_mr_cleanup();
1293         icmpv6_cleanup();
1294         rawv6_exit();
1295
1296         unregister_pernet_subsys(&inet6_net_ops);
1297 #ifdef CONFIG_SYSCTL
1298         ipv6_static_sysctl_unregister();
1299 #endif
1300         proto_unregister(&rawv6_prot);
1301         proto_unregister(&udplitev6_prot);
1302         proto_unregister(&udpv6_prot);
1303         proto_unregister(&tcpv6_prot);
1304
1305         rcu_barrier(); /* Wait for completion of call_rcu()'s */
1306 }
1307 module_exit(inet6_exit);
1308
1309 MODULE_ALIAS_NETPROTO(PF_INET6);