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 consitant */
 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 (!ipv6_chk_addr(net, &addr->sin6_addr,
 347                                                    dev, 0)) {
 348                                         err = -EADDRNOTAVAIL;
 349                                         goto out_unlock;
 350                                 }
 351                         }
 352                         rcu_read_unlock();
 353                 }
 354         }
 355
 356         inet->inet_rcv_saddr = v4addr;
 357         inet->inet_saddr = v4addr;
 358
 359         ipv6_addr_copy(&np->rcv_saddr, &addr->sin6_addr);
 360
 361         if (!(addr_type & IPV6_ADDR_MULTICAST))
 362                 ipv6_addr_copy(&np->saddr, &addr->sin6_addr);
 363
 364         /* Make sure we are allowed to bind here. */
 365         if (sk->sk_prot->get_port(sk, snum)) {
 366                 inet_reset_saddr(sk);
 367                 err = -EADDRINUSE;
 368                 goto out;
 369         }
 370
 371         if (addr_type != IPV6_ADDR_ANY) {
 372                 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
 373                 if (addr_type != IPV6_ADDR_MAPPED)
 374                         np->ipv6only = 1;
 375         }
 376         if (snum)
 377                 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
 378         inet->inet_sport = htons(inet->inet_num);
 379         inet->inet_dport = 0;
 380         inet->inet_daddr = 0;
 381 out:
 382         release_sock(sk);
 383         return err;
 384 out_unlock:
 385         rcu_read_unlock();
 386         goto out;
 387 }
 388
 389 EXPORT_SYMBOL(inet6_bind);
 390
 391 int inet6_release(struct socket *sock)
 392 {
 393         struct sock *sk = sock->sk;
 394
 395         if (sk == NULL)
 396                 return -EINVAL;
 397
 398         /* Free mc lists */
 399         ipv6_sock_mc_close(sk);
 400
 401         /* Free ac lists */
 402         ipv6_sock_ac_close(sk);
 403
 404         return inet_release(sock);
 405 }
 406
 407 EXPORT_SYMBOL(inet6_release);
 408
 409 void inet6_destroy_sock(struct sock *sk)
 410 {
 411         struct ipv6_pinfo *np = inet6_sk(sk);
 412         struct sk_buff *skb;
 413         struct ipv6_txoptions *opt;
 414
 415         /* Release rx options */
 416
 417         if ((skb = xchg(&np->pktoptions, NULL)) != NULL)
 418                 kfree_skb(skb);
 419
 420         /* Free flowlabels */
 421         fl6_free_socklist(sk);
 422
 423         /* Free tx options */
 424
 425         if ((opt = xchg(&np->opt, NULL)) != NULL)
 426                 sock_kfree_s(sk, opt, opt->tot_len);
 427 }
 428
 429 EXPORT_SYMBOL_GPL(inet6_destroy_sock);
 430
 431 /*
 432  *      This does both peername and sockname.
 433  */
 434
 435 int inet6_getname(struct socket *sock, struct sockaddr *uaddr,
 436                  int *uaddr_len, int peer)
 437 {
 438         struct sockaddr_in6 *sin=(struct sockaddr_in6 *)uaddr;
 439         struct sock *sk = sock->sk;
 440         struct inet_sock *inet = inet_sk(sk);
 441         struct ipv6_pinfo *np = inet6_sk(sk);
 442
 443         sin->sin6_family = AF_INET6;
 444         sin->sin6_flowinfo = 0;
 445         sin->sin6_scope_id = 0;
 446         if (peer) {
 447                 if (!inet->inet_dport)
 448                         return -ENOTCONN;
 449                 if (((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_SYN_SENT)) &&
 450                     peer == 1)
 451                         return -ENOTCONN;
 452                 sin->sin6_port = inet->inet_dport;
 453                 ipv6_addr_copy(&sin->sin6_addr, &np->daddr);
 454                 if (np->sndflow)
 455                         sin->sin6_flowinfo = np->flow_label;
 456         } else {
 457                 if (ipv6_addr_any(&np->rcv_saddr))
 458                         ipv6_addr_copy(&sin->sin6_addr, &np->saddr);
 459                 else
 460                         ipv6_addr_copy(&sin->sin6_addr, &np->rcv_saddr);
 461
 462                 sin->sin6_port = inet->inet_sport;
 463         }
 464         if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
 465                 sin->sin6_scope_id = sk->sk_bound_dev_if;
 466         *uaddr_len = sizeof(*sin);
 467         return(0);
 468 }
 469
 470 EXPORT_SYMBOL(inet6_getname);
 471
 472 int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
 473 {
 474         struct sock *sk = sock->sk;
 475         struct net *net = sock_net(sk);
 476
 477         switch(cmd)
 478         {
 479         case SIOCGSTAMP:
 480                 return sock_get_timestamp(sk, (struct timeval __user *)arg);
 481
 482         case SIOCGSTAMPNS:
 483                 return sock_get_timestampns(sk, (struct timespec __user *)arg);
 484
 485         case SIOCADDRT:
 486         case SIOCDELRT:
 487
 488                 return(ipv6_route_ioctl(net, cmd, (void __user *)arg));
 489
 490         case SIOCSIFADDR:
 491                 return addrconf_add_ifaddr(net, (void __user *) arg);
 492         case SIOCDIFADDR:
 493                 return addrconf_del_ifaddr(net, (void __user *) arg);
 494         case SIOCSIFDSTADDR:
 495                 return addrconf_set_dstaddr(net, (void __user *) arg);
 496         default:
 497                 if (!sk->sk_prot->ioctl)
 498                         return -ENOIOCTLCMD;
 499                 return sk->sk_prot->ioctl(sk, cmd, arg);
 500         }
 501         /*NOTREACHED*/
 502         return(0);
 503 }
 504
 505 EXPORT_SYMBOL(inet6_ioctl);
 506
 507 const struct proto_ops inet6_stream_ops = {
 508         .family            = PF_INET6,
 509         .owner             = THIS_MODULE,
 510         .release           = inet6_release,
 511         .bind              = inet6_bind,
 512         .connect           = inet_stream_connect,       /* ok           */
 513         .socketpair        = sock_no_socketpair,        /* a do nothing */
 514         .accept            = inet_accept,               /* ok           */
 515         .getname           = inet6_getname,
 516         .poll              = tcp_poll,                  /* ok           */
 517         .ioctl             = inet6_ioctl,               /* must change  */
 518         .listen            = inet_listen,               /* ok           */
 519         .shutdown          = inet_shutdown,             /* ok           */
 520         .setsockopt        = sock_common_setsockopt,    /* ok           */
 521         .getsockopt        = sock_common_getsockopt,    /* ok           */
 522         .sendmsg           = tcp_sendmsg,               /* ok           */
 523         .recvmsg           = sock_common_recvmsg,       /* ok           */
 524         .mmap              = sock_no_mmap,
 525         .sendpage          = tcp_sendpage,
 526         .splice_read       = tcp_splice_read,
 527 #ifdef CONFIG_COMPAT
 528         .compat_setsockopt = compat_sock_common_setsockopt,
 529         .compat_getsockopt = compat_sock_common_getsockopt,
 530 #endif
 531 };
 532
 533 const struct proto_ops inet6_dgram_ops = {
 534         .family            = PF_INET6,
 535         .owner             = THIS_MODULE,
 536         .release           = inet6_release,
 537         .bind              = inet6_bind,
 538         .connect           = inet_dgram_connect,        /* ok           */
 539         .socketpair        = sock_no_socketpair,        /* a do nothing */
 540         .accept            = sock_no_accept,            /* a do nothing */
 541         .getname           = inet6_getname,
 542         .poll              = udp_poll,                  /* ok           */
 543         .ioctl             = inet6_ioctl,               /* must change  */
 544         .listen            = sock_no_listen,            /* ok           */
 545         .shutdown          = inet_shutdown,             /* ok           */
 546         .setsockopt        = sock_common_setsockopt,    /* ok           */
 547         .getsockopt        = sock_common_getsockopt,    /* ok           */
 548         .sendmsg           = inet_sendmsg,              /* ok           */
 549         .recvmsg           = sock_common_recvmsg,       /* ok           */
 550         .mmap              = sock_no_mmap,
 551         .sendpage          = sock_no_sendpage,
 552 #ifdef CONFIG_COMPAT
 553         .compat_setsockopt = compat_sock_common_setsockopt,
 554         .compat_getsockopt = compat_sock_common_getsockopt,
 555 #endif
 556 };
 557
 558 static const struct net_proto_family inet6_family_ops = {
 559         .family = PF_INET6,
 560         .create = inet6_create,
 561         .owner  = THIS_MODULE,
 562 };
 563
 564 int inet6_register_protosw(struct inet_protosw *p)
 565 {
 566         struct list_head *lh;
 567         struct inet_protosw *answer;
 568         struct list_head *last_perm;
 569         int protocol = p->protocol;
 570         int ret;
 571
 572         spin_lock_bh(&inetsw6_lock);
 573
 574         ret = -EINVAL;
 575         if (p->type >= SOCK_MAX)
 576                 goto out_illegal;
 577
 578         /* If we are trying to override a permanent protocol, bail. */
 579         answer = NULL;
 580         ret = -EPERM;
 581         last_perm = &inetsw6[p->type];
 582         list_for_each(lh, &inetsw6[p->type]) {
 583                 answer = list_entry(lh, struct inet_protosw, list);
 584
 585                 /* Check only the non-wild match. */
 586                 if (INET_PROTOSW_PERMANENT & answer->flags) {
 587                         if (protocol == answer->protocol)
 588                                 break;
 589                         last_perm = lh;
 590                 }
 591
 592                 answer = NULL;
 593         }
 594         if (answer)
 595                 goto out_permanent;
 596
 597         /* Add the new entry after the last permanent entry if any, so that
 598          * the new entry does not override a permanent entry when matched with
 599          * a wild-card protocol. But it is allowed to override any existing
 600          * non-permanent entry.  This means that when we remove this entry, the
 601          * system automatically returns to the old behavior.
 602          */
 603         list_add_rcu(&p->list, last_perm);
 604         ret = 0;
 605 out:
 606         spin_unlock_bh(&inetsw6_lock);
 607         return ret;
 608
 609 out_permanent:
 610         printk(KERN_ERR "Attempt to override permanent protocol %d.\n",
 611                protocol);
 612         goto out;
 613
 614 out_illegal:
 615         printk(KERN_ERR
 616                "Ignoring attempt to register invalid socket type %d.\n",
 617                p->type);
 618         goto out;
 619 }
 620
 621 EXPORT_SYMBOL(inet6_register_protosw);
 622
 623 void
 624 inet6_unregister_protosw(struct inet_protosw *p)
 625 {
 626         if (INET_PROTOSW_PERMANENT & p->flags) {
 627                 printk(KERN_ERR
 628                        "Attempt to unregister permanent protocol %d.\n",
 629                        p->protocol);
 630         } else {
 631                 spin_lock_bh(&inetsw6_lock);
 632                 list_del_rcu(&p->list);
 633                 spin_unlock_bh(&inetsw6_lock);
 634
 635                 synchronize_net();
 636         }
 637 }
 638
 639 EXPORT_SYMBOL(inet6_unregister_protosw);
 640
 641 int inet6_sk_rebuild_header(struct sock *sk)
 642 {
 643         int err;
 644         struct dst_entry *dst;
 645         struct ipv6_pinfo *np = inet6_sk(sk);
 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 = NULL, final;
 652                 struct flowi fl;
 653
 654                 memset(&fl, 0, sizeof(fl));
 655                 fl.proto = sk->sk_protocol;
 656                 ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
 657                 ipv6_addr_copy(&fl.fl6_src, &np->saddr);
 658                 fl.fl6_flowlabel = np->flow_label;
 659                 fl.oif = sk->sk_bound_dev_if;
 660                 fl.mark = sk->sk_mark;
 661                 fl.fl_ip_dport = inet->inet_dport;
 662                 fl.fl_ip_sport = inet->inet_sport;
 663                 security_sk_classify_flow(sk, &fl);
 664
 665                 if (np->opt && np->opt->srcrt) {
 666                         struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt;
 667                         ipv6_addr_copy(&final, &fl.fl6_dst);
 668                         ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
 669                         final_p = &final;
 670                 }
 671
 672                 err = ip6_dst_lookup(sk, &dst, &fl);
 673                 if (err) {
 674                         sk->sk_route_caps = 0;
 675                         return err;
 676                 }
 677                 if (final_p)
 678                         ipv6_addr_copy(&fl.fl6_dst, final_p);
 679
 680                 if ((err = xfrm_lookup(sock_net(sk), &dst, &fl, sk, 0)) < 0) {
 681                         sk->sk_err_soft = -err;
 682                         return err;
 683                 }
 684
 685                 __ip6_dst_store(sk, dst, NULL, NULL);
 686         }
 687
 688         return 0;
 689 }
 690
 691 EXPORT_SYMBOL_GPL(inet6_sk_rebuild_header);
 692
 693 int ipv6_opt_accepted(struct sock *sk, struct sk_buff *skb)
 694 {
 695         struct ipv6_pinfo *np = inet6_sk(sk);
 696         struct inet6_skb_parm *opt = IP6CB(skb);
 697
 698         if (np->rxopt.all) {
 699                 if ((opt->hop && (np->rxopt.bits.hopopts ||
 700                                   np->rxopt.bits.ohopopts)) ||
 701                     ((IPV6_FLOWINFO_MASK &
 702                       *(__be32 *)skb_network_header(skb)) &&
 703                      np->rxopt.bits.rxflow) ||
 704                     (opt->srcrt && (np->rxopt.bits.srcrt ||
 705                      np->rxopt.bits.osrcrt)) ||
 706                     ((opt->dst1 || opt->dst0) &&
 707                      (np->rxopt.bits.dstopts || np->rxopt.bits.odstopts)))
 708                         return 1;
 709         }
 710         return 0;
 711 }
 712
 713 EXPORT_SYMBOL_GPL(ipv6_opt_accepted);
 714
 715 static int ipv6_gso_pull_exthdrs(struct sk_buff *skb, int proto)
 716 {
 717         const struct inet6_protocol *ops = NULL;
 718
 719         for (;;) {
 720                 struct ipv6_opt_hdr *opth;
 721                 int len;
 722
 723                 if (proto != NEXTHDR_HOP) {
 724                         ops = rcu_dereference(inet6_protos[proto]);
 725
 726                         if (unlikely(!ops))
 727                                 break;
 728
 729                         if (!(ops->flags & INET6_PROTO_GSO_EXTHDR))
 730                                 break;
 731                 }
 732
 733                 if (unlikely(!pskb_may_pull(skb, 8)))
 734                         break;
 735
 736                 opth = (void *)skb->data;
 737                 len = ipv6_optlen(opth);
 738
 739                 if (unlikely(!pskb_may_pull(skb, len)))
 740                         break;
 741
 742                 proto = opth->nexthdr;
 743                 __skb_pull(skb, len);
 744         }
 745
 746         return proto;
 747 }
 748
 749 static int ipv6_gso_send_check(struct sk_buff *skb)
 750 {
 751         struct ipv6hdr *ipv6h;
 752         const struct inet6_protocol *ops;
 753         int err = -EINVAL;
 754
 755         if (unlikely(!pskb_may_pull(skb, sizeof(*ipv6h))))
 756                 goto out;
 757
 758         ipv6h = ipv6_hdr(skb);
 759         __skb_pull(skb, sizeof(*ipv6h));
 760         err = -EPROTONOSUPPORT;
 761
 762         rcu_read_lock();
 763         ops = rcu_dereference(inet6_protos[
 764                 ipv6_gso_pull_exthdrs(skb, ipv6h->nexthdr)]);
 765
 766         if (likely(ops && ops->gso_send_check)) {
 767                 skb_reset_transport_header(skb);
 768                 err = ops->gso_send_check(skb);
 769         }
 770         rcu_read_unlock();
 771
 772 out:
 773         return err;
 774 }
 775
 776 static struct sk_buff *ipv6_gso_segment(struct sk_buff *skb, int features)
 777 {
 778         struct sk_buff *segs = ERR_PTR(-EINVAL);
 779         struct ipv6hdr *ipv6h;
 780         const struct inet6_protocol *ops;
 781         int proto;
 782         struct frag_hdr *fptr;
 783         unsigned int unfrag_ip6hlen;
 784         u8 *prevhdr;
 785         int offset = 0;
 786
 787         if (!(features & NETIF_F_V6_CSUM))
 788                 features &= ~NETIF_F_SG;
 789
 790         if (unlikely(skb_shinfo(skb)->gso_type &
 791                      ~(SKB_GSO_UDP |
 792                        SKB_GSO_DODGY |
 793                        SKB_GSO_TCP_ECN |
 794                        SKB_GSO_TCPV6 |
 795                        0)))
 796                 goto out;
 797
 798         if (unlikely(!pskb_may_pull(skb, sizeof(*ipv6h))))
 799                 goto out;
 800
 801         ipv6h = ipv6_hdr(skb);
 802         __skb_pull(skb, sizeof(*ipv6h));
 803         segs = ERR_PTR(-EPROTONOSUPPORT);
 804
 805         proto = ipv6_gso_pull_exthdrs(skb, ipv6h->nexthdr);
 806         rcu_read_lock();
 807         ops = rcu_dereference(inet6_protos[proto]);
 808         if (likely(ops && ops->gso_segment)) {
 809                 skb_reset_transport_header(skb);
 810                 segs = ops->gso_segment(skb, features);
 811         }
 812         rcu_read_unlock();
 813
 814         if (unlikely(IS_ERR(segs)))
 815                 goto out;
 816
 817         for (skb = segs; skb; skb = skb->next) {
 818                 ipv6h = ipv6_hdr(skb);
 819                 ipv6h->payload_len = htons(skb->len - skb->mac_len -
 820                                            sizeof(*ipv6h));
 821                 if (proto == IPPROTO_UDP) {
 822                         unfrag_ip6hlen = ip6_find_1stfragopt(skb, &prevhdr);
 823                         fptr = (struct frag_hdr *)(skb_network_header(skb) +
 824                                 unfrag_ip6hlen);
 825                         fptr->frag_off = htons(offset);
 826                         if (skb->next != NULL)
 827                                 fptr->frag_off |= htons(IP6_MF);
 828                         offset += (ntohs(ipv6h->payload_len) -
 829                                    sizeof(struct frag_hdr));
 830                 }
 831         }
 832
 833 out:
 834         return segs;
 835 }
 836
 837 struct ipv6_gro_cb {
 838         struct napi_gro_cb napi;
 839         int proto;
 840 };
 841
 842 #define IPV6_GRO_CB(skb) ((struct ipv6_gro_cb *)(skb)->cb)
 843
 844 static struct sk_buff **ipv6_gro_receive(struct sk_buff **head,
 845                                          struct sk_buff *skb)
 846 {
 847         const struct inet6_protocol *ops;
 848         struct sk_buff **pp = NULL;
 849         struct sk_buff *p;
 850         struct ipv6hdr *iph;
 851         unsigned int nlen;
 852         unsigned int hlen;
 853         unsigned int off;
 854         int flush = 1;
 855         int proto;
 856         __wsum csum;
 857
 858         off = skb_gro_offset(skb);
 859         hlen = off + sizeof(*iph);
 860         iph = skb_gro_header_fast(skb, off);
 861         if (skb_gro_header_hard(skb, hlen)) {
 862                 iph = skb_gro_header_slow(skb, hlen, off);
 863                 if (unlikely(!iph))
 864                         goto out;
 865         }
 866
 867         skb_gro_pull(skb, sizeof(*iph));
 868         skb_set_transport_header(skb, skb_gro_offset(skb));
 869
 870         flush += ntohs(iph->payload_len) != skb_gro_len(skb);
 871
 872         rcu_read_lock();
 873         proto = iph->nexthdr;
 874         ops = rcu_dereference(inet6_protos[proto]);
 875         if (!ops || !ops->gro_receive) {
 876                 __pskb_pull(skb, skb_gro_offset(skb));
 877                 proto = ipv6_gso_pull_exthdrs(skb, proto);
 878                 skb_gro_pull(skb, -skb_transport_offset(skb));
 879                 skb_reset_transport_header(skb);
 880                 __skb_push(skb, skb_gro_offset(skb));
 881
 882                 if (!ops || !ops->gro_receive)
 883                         goto out_unlock;
 884
 885                 iph = ipv6_hdr(skb);
 886         }
 887
 888         IPV6_GRO_CB(skb)->proto = proto;
 889
 890         flush--;
 891         nlen = skb_network_header_len(skb);
 892
 893         for (p = *head; p; p = p->next) {
 894                 struct ipv6hdr *iph2;
 895
 896                 if (!NAPI_GRO_CB(p)->same_flow)
 897                         continue;
 898
 899                 iph2 = ipv6_hdr(p);
 900
 901                 /* All fields must match except length. */
 902                 if (nlen != skb_network_header_len(p) ||
 903                     memcmp(iph, iph2, offsetof(struct ipv6hdr, payload_len)) ||
 904                     memcmp(&iph->nexthdr, &iph2->nexthdr,
 905                            nlen - offsetof(struct ipv6hdr, nexthdr))) {
 906                         NAPI_GRO_CB(p)->same_flow = 0;
 907                         continue;
 908                 }
 909
 910                 NAPI_GRO_CB(p)->flush |= flush;
 911         }
 912
 913         NAPI_GRO_CB(skb)->flush |= flush;
 914
 915         csum = skb->csum;
 916         skb_postpull_rcsum(skb, iph, skb_network_header_len(skb));
 917
 918         pp = ops->gro_receive(head, skb);
 919
 920         skb->csum = csum;
 921
 922 out_unlock:
 923         rcu_read_unlock();
 924
 925 out:
 926         NAPI_GRO_CB(skb)->flush |= flush;
 927
 928         return pp;
 929 }
 930
 931 static int ipv6_gro_complete(struct sk_buff *skb)
 932 {
 933         const struct inet6_protocol *ops;
 934         struct ipv6hdr *iph = ipv6_hdr(skb);
 935         int err = -ENOSYS;
 936
 937         iph->payload_len = htons(skb->len - skb_network_offset(skb) -
 938                                  sizeof(*iph));
 939
 940         rcu_read_lock();
 941         ops = rcu_dereference(inet6_protos[IPV6_GRO_CB(skb)->proto]);
 942         if (WARN_ON(!ops || !ops->gro_complete))
 943                 goto out_unlock;
 944
 945         err = ops->gro_complete(skb);
 946
 947 out_unlock:
 948         rcu_read_unlock();
 949
 950         return err;
 951 }
 952
 953 static struct packet_type ipv6_packet_type __read_mostly = {
 954         .type = cpu_to_be16(ETH_P_IPV6),
 955         .func = ipv6_rcv,
 956         .gso_send_check = ipv6_gso_send_check,
 957         .gso_segment = ipv6_gso_segment,
 958         .gro_receive = ipv6_gro_receive,
 959         .gro_complete = ipv6_gro_complete,
 960 };
 961
 962 static int __init ipv6_packet_init(void)
 963 {
 964         dev_add_pack(&ipv6_packet_type);
 965         return 0;
 966 }
 967
 968 static void ipv6_packet_cleanup(void)
 969 {
 970         dev_remove_pack(&ipv6_packet_type);
 971 }
 972
 973 static int __net_init ipv6_init_mibs(struct net *net)
 974 {
 975         if (snmp_mib_init((void __percpu **)net->mib.udp_stats_in6,
 976                           sizeof (struct udp_mib)) < 0)
 977                 return -ENOMEM;
 978         if (snmp_mib_init((void __percpu **)net->mib.udplite_stats_in6,
 979                           sizeof (struct udp_mib)) < 0)
 980                 goto err_udplite_mib;
 981         if (snmp_mib_init((void __percpu **)net->mib.ipv6_statistics,
 982                           sizeof(struct ipstats_mib)) < 0)
 983                 goto err_ip_mib;
 984         if (snmp_mib_init((void __percpu **)net->mib.icmpv6_statistics,
 985                           sizeof(struct icmpv6_mib)) < 0)
 986                 goto err_icmp_mib;
 987         if (snmp_mib_init((void __percpu **)net->mib.icmpv6msg_statistics,
 988                           sizeof(struct icmpv6msg_mib)) < 0)
 989                 goto err_icmpmsg_mib;
 990         return 0;
 991
 992 err_icmpmsg_mib:
 993         snmp_mib_free((void __percpu **)net->mib.icmpv6_statistics);
 994 err_icmp_mib:
 995         snmp_mib_free((void __percpu **)net->mib.ipv6_statistics);
 996 err_ip_mib:
 997         snmp_mib_free((void __percpu **)net->mib.udplite_stats_in6);
 998 err_udplite_mib:
 999         snmp_mib_free((void __percpu **)net->mib.udp_stats_in6);
1000         return -ENOMEM;
1001 }
1002
1003 static void ipv6_cleanup_mibs(struct net *net)
1004 {
1005         snmp_mib_free((void __percpu **)net->mib.udp_stats_in6);
1006         snmp_mib_free((void __percpu **)net->mib.udplite_stats_in6);
1007         snmp_mib_free((void __percpu **)net->mib.ipv6_statistics);
1008         snmp_mib_free((void __percpu **)net->mib.icmpv6_statistics);
1009         snmp_mib_free((void __percpu **)net->mib.icmpv6msg_statistics);
1010 }
1011
1012 static int __net_init inet6_net_init(struct net *net)
1013 {
1014         int err = 0;
1015
1016         net->ipv6.sysctl.bindv6only = 0;
1017         net->ipv6.sysctl.icmpv6_time = 1*HZ;
1018
1019         err = ipv6_init_mibs(net);
1020         if (err)
1021                 return err;
1022 #ifdef CONFIG_PROC_FS
1023         err = udp6_proc_init(net);
1024         if (err)
1025                 goto out;
1026         err = tcp6_proc_init(net);
1027         if (err)
1028                 goto proc_tcp6_fail;
1029         err = ac6_proc_init(net);
1030         if (err)
1031                 goto proc_ac6_fail;
1032 #endif
1033         return err;
1034
1035 #ifdef CONFIG_PROC_FS
1036 proc_ac6_fail:
1037         tcp6_proc_exit(net);
1038 proc_tcp6_fail:
1039         udp6_proc_exit(net);
1040 out:
1041         ipv6_cleanup_mibs(net);
1042         return err;
1043 #endif
1044 }
1045
1046 static void __net_exit inet6_net_exit(struct net *net)
1047 {
1048 #ifdef CONFIG_PROC_FS
1049         udp6_proc_exit(net);
1050         tcp6_proc_exit(net);
1051         ac6_proc_exit(net);
1052 #endif
1053         ipv6_cleanup_mibs(net);
1054 }
1055
1056 static struct pernet_operations inet6_net_ops = {
1057         .init = inet6_net_init,
1058         .exit = inet6_net_exit,
1059 };
1060
1061 static int __init inet6_init(void)
1062 {
1063         struct sk_buff *dummy_skb;
1064         struct list_head *r;
1065         int err = 0;
1066
1067         BUILD_BUG_ON(sizeof(struct inet6_skb_parm) > sizeof(dummy_skb->cb));
1068
1069         /* Register the socket-side information for inet6_create.  */
1070         for(r = &inetsw6[0]; r < &inetsw6[SOCK_MAX]; ++r)
1071                 INIT_LIST_HEAD(r);
1072
1073         if (disable_ipv6_mod) {
1074                 printk(KERN_INFO
1075                        "IPv6: Loaded, but administratively disabled, "
1076                        "reboot required to enable\n");
1077                 goto out;
1078         }
1079
1080         err = proto_register(&tcpv6_prot, 1);
1081         if (err)
1082                 goto out;
1083
1084         err = proto_register(&udpv6_prot, 1);
1085         if (err)
1086                 goto out_unregister_tcp_proto;
1087
1088         err = proto_register(&udplitev6_prot, 1);
1089         if (err)
1090                 goto out_unregister_udp_proto;
1091
1092         err = proto_register(&rawv6_prot, 1);
1093         if (err)
1094                 goto out_unregister_udplite_proto;
1095
1096
1097         /* We MUST register RAW sockets before we create the ICMP6,
1098          * IGMP6, or NDISC control sockets.
1099          */
1100         err = rawv6_init();
1101         if (err)
1102                 goto out_unregister_raw_proto;
1103
1104         /* Register the family here so that the init calls below will
1105          * be able to create sockets. (?? is this dangerous ??)
1106          */
1107         err = sock_register(&inet6_family_ops);
1108         if (err)
1109                 goto out_sock_register_fail;
1110
1111 #ifdef CONFIG_SYSCTL
1112         err = ipv6_static_sysctl_register();
1113         if (err)
1114                 goto static_sysctl_fail;
1115 #endif
1116         /*
1117          *      ipngwg API draft makes clear that the correct semantics
1118          *      for TCP and UDP is to consider one TCP and UDP instance
1119          *      in a host availiable by both INET and INET6 APIs and
1120          *      able to communicate via both network protocols.
1121          */
1122
1123         err = register_pernet_subsys(&inet6_net_ops);
1124         if (err)
1125                 goto register_pernet_fail;
1126         err = icmpv6_init();
1127         if (err)
1128                 goto icmp_fail;
1129         err = ip6_mr_init();
1130         if (err)
1131                 goto ipmr_fail;
1132         err = ndisc_init();
1133         if (err)
1134                 goto ndisc_fail;
1135         err = igmp6_init();
1136         if (err)
1137                 goto igmp_fail;
1138         err = ipv6_netfilter_init();
1139         if (err)
1140                 goto netfilter_fail;
1141         /* Create /proc/foo6 entries. */
1142 #ifdef CONFIG_PROC_FS
1143         err = -ENOMEM;
1144         if (raw6_proc_init())
1145                 goto proc_raw6_fail;
1146         if (udplite6_proc_init())
1147                 goto proc_udplite6_fail;
1148         if (ipv6_misc_proc_init())
1149                 goto proc_misc6_fail;
1150         if (if6_proc_init())
1151                 goto proc_if6_fail;
1152 #endif
1153         err = ip6_route_init();
1154         if (err)
1155                 goto ip6_route_fail;
1156         err = ip6_flowlabel_init();
1157         if (err)
1158                 goto ip6_flowlabel_fail;
1159         err = addrconf_init();
1160         if (err)
1161                 goto addrconf_fail;
1162
1163         /* Init v6 extension headers. */
1164         err = ipv6_exthdrs_init();
1165         if (err)
1166                 goto ipv6_exthdrs_fail;
1167
1168         err = ipv6_frag_init();
1169         if (err)
1170                 goto ipv6_frag_fail;
1171
1172         /* Init v6 transport protocols. */
1173         err = udpv6_init();
1174         if (err)
1175                 goto udpv6_fail;
1176
1177         err = udplitev6_init();
1178         if (err)
1179                 goto udplitev6_fail;
1180
1181         err = tcpv6_init();
1182         if (err)
1183                 goto tcpv6_fail;
1184
1185         err = ipv6_packet_init();
1186         if (err)
1187                 goto ipv6_packet_fail;
1188
1189 #ifdef CONFIG_SYSCTL
1190         err = ipv6_sysctl_register();
1191         if (err)
1192                 goto sysctl_fail;
1193 #endif
1194 out:
1195         return err;
1196
1197 #ifdef CONFIG_SYSCTL
1198 sysctl_fail:
1199         ipv6_packet_cleanup();
1200 #endif
1201 ipv6_packet_fail:
1202         tcpv6_exit();
1203 tcpv6_fail:
1204         udplitev6_exit();
1205 udplitev6_fail:
1206         udpv6_exit();
1207 udpv6_fail:
1208         ipv6_frag_exit();
1209 ipv6_frag_fail:
1210         ipv6_exthdrs_exit();
1211 ipv6_exthdrs_fail:
1212         addrconf_cleanup();
1213 addrconf_fail:
1214         ip6_flowlabel_cleanup();
1215 ip6_flowlabel_fail:
1216         ip6_route_cleanup();
1217 ip6_route_fail:
1218 #ifdef CONFIG_PROC_FS
1219         if6_proc_exit();
1220 proc_if6_fail:
1221         ipv6_misc_proc_exit();
1222 proc_misc6_fail:
1223         udplite6_proc_exit();
1224 proc_udplite6_fail:
1225         raw6_proc_exit();
1226 proc_raw6_fail:
1227 #endif
1228         ipv6_netfilter_fini();
1229 netfilter_fail:
1230         igmp6_cleanup();
1231 igmp_fail:
1232         ndisc_cleanup();
1233 ndisc_fail:
1234         ip6_mr_cleanup();
1235 ipmr_fail:
1236         icmpv6_cleanup();
1237 icmp_fail:
1238         unregister_pernet_subsys(&inet6_net_ops);
1239 register_pernet_fail:
1240 #ifdef CONFIG_SYSCTL
1241         ipv6_static_sysctl_unregister();
1242 static_sysctl_fail:
1243 #endif
1244         sock_unregister(PF_INET6);
1245         rtnl_unregister_all(PF_INET6);
1246 out_sock_register_fail:
1247         rawv6_exit();
1248 out_unregister_raw_proto:
1249         proto_unregister(&rawv6_prot);
1250 out_unregister_udplite_proto:
1251         proto_unregister(&udplitev6_prot);
1252 out_unregister_udp_proto:
1253         proto_unregister(&udpv6_prot);
1254 out_unregister_tcp_proto:
1255         proto_unregister(&tcpv6_prot);
1256         goto out;
1257 }
1258 module_init(inet6_init);
1259
1260 static void __exit inet6_exit(void)
1261 {
1262         if (disable_ipv6_mod)
1263                 return;
1264
1265         /* First of all disallow new sockets creation. */
1266         sock_unregister(PF_INET6);
1267         /* Disallow any further netlink messages */
1268         rtnl_unregister_all(PF_INET6);
1269
1270 #ifdef CONFIG_SYSCTL
1271         ipv6_sysctl_unregister();
1272 #endif
1273         udpv6_exit();
1274         udplitev6_exit();
1275         tcpv6_exit();
1276
1277         /* Cleanup code parts. */
1278         ipv6_packet_cleanup();
1279         ipv6_frag_exit();
1280         ipv6_exthdrs_exit();
1281         addrconf_cleanup();
1282         ip6_flowlabel_cleanup();
1283         ip6_route_cleanup();
1284 #ifdef CONFIG_PROC_FS
1285
1286         /* Cleanup code parts. */
1287         if6_proc_exit();
1288         ipv6_misc_proc_exit();
1289         udplite6_proc_exit();
1290         raw6_proc_exit();
1291 #endif
1292         ipv6_netfilter_fini();
1293         igmp6_cleanup();
1294         ndisc_cleanup();
1295         ip6_mr_cleanup();
1296         icmpv6_cleanup();
1297         rawv6_exit();
1298
1299         unregister_pernet_subsys(&inet6_net_ops);
1300 #ifdef CONFIG_SYSCTL
1301         ipv6_static_sysctl_unregister();
1302 #endif
1303         proto_unregister(&rawv6_prot);
1304         proto_unregister(&udplitev6_prot);
1305         proto_unregister(&udpv6_prot);
1306         proto_unregister(&tcpv6_prot);
1307
1308         rcu_barrier(); /* Wait for completion of call_rcu()'s */
1309 }
1310 module_exit(inet6_exit);
1311
1312 MODULE_ALIAS_NETPROTO(PF_INET6);