net/ipv6/ipv6_sockglue.c

   1 /*
   2  *      IPv6 BSD socket options interface
   3  *      Linux INET6 implementation
   4  *
   5  *      Authors:
   6  *      Pedro Roque             <roque@di.fc.ul.pt>
   7  *
   8  *      Based on linux/net/ipv4/ip_sockglue.c
   9  *
  10  *      $Id: ipv6_sockglue.c,v 1.1.1.1 2005/04/11 02:51:13 jack Exp $
  11  *
  12  *      This program is free software; you can redistribute it and/or
  13  *      modify it under the terms of the GNU General Public License
  14  *      as published by the Free Software Foundation; either version
  15  *      2 of the License, or (at your option) any later version.
  16  *
  17  *      FIXME: Make the setsockopt code POSIX compliant: That is
  18  *
  19  *      o       Return -EINVAL for setsockopt of short lengths
  20  *      o       Truncate getsockopt returns
  21  *      o       Return an optlen of the truncated length if need be
  22  */
  23
  24 #define __NO_VERSION__
  25 #include <linux/module.h>
  26 #include <linux/config.h>
  27 #include <linux/errno.h>
  28 #include <linux/types.h>
  29 #include <linux/socket.h>
  30 #include <linux/sockios.h>
  31 #include <linux/sched.h>
  32 #include <linux/net.h>
  33 #include <linux/in6.h>
  34 #include <linux/netdevice.h>
  35 #include <linux/if_arp.h>
  36 #include <linux/init.h>
  37 #include <linux/sysctl.h>
  38 #include <linux/netfilter.h>
  39
  40 #include <net/sock.h>
  41 #include <net/snmp.h>
  42 #include <net/ipv6.h>
  43 #include <net/ndisc.h>
  44 #include <net/protocol.h>
  45 #include <net/transp_v6.h>
  46 #include <net/ip6_route.h>
  47 #include <net/addrconf.h>
  48 #include <net/inet_common.h>
  49 #include <net/tcp.h>
  50 #include <net/udp.h>
  51
  52 #include <asm/uaccess.h>
  53
  54 struct ipv6_mib ipv6_statistics[NR_CPUS*2];
  55
  56 struct packet_type ipv6_packet_type =
  57 {
  58         __constant_htons(ETH_P_IPV6),
  59         NULL,                                   /* All devices */
  60         ipv6_rcv,
  61         (void*)1,
  62         NULL
  63 };
  64
  65 /*
  66  *      addrconf module should be notifyed of a device going up
  67  */
  68 static struct notifier_block ipv6_dev_notf = {
  69         addrconf_notify,
  70         NULL,
  71         0
  72 };
  73
  74 struct ip6_ra_chain *ip6_ra_chain;
  75 rwlock_t ip6_ra_lock = RW_LOCK_UNLOCKED;
  76
  77 int ip6_ra_control(struct sock *sk, int sel, void (*destructor)(struct sock *))
  78 {
  79         struct ip6_ra_chain *ra, *new_ra, **rap;
  80
  81         /* RA packet may be delivered ONLY to IPPROTO_RAW socket */
  82         if (sk->type != SOCK_RAW || sk->num != IPPROTO_RAW)
  83                 return -EINVAL;
  84
  85         new_ra = (sel>=0) ? kmalloc(sizeof(*new_ra), GFP_KERNEL) : NULL;
  86
  87         write_lock_bh(&ip6_ra_lock);
  88         for (rap = &ip6_ra_chain; (ra=*rap) != NULL; rap = &ra->next) {
  89                 if (ra->sk == sk) {
  90                         if (sel>=0) {
  91                                 write_unlock_bh(&ip6_ra_lock);
  92                                 if (new_ra)
  93                                         kfree(new_ra);
  94                                 return -EADDRINUSE;
  95                         }
  96
  97                         *rap = ra->next;
  98                         write_unlock_bh(&ip6_ra_lock);
  99
 100                         if (ra->destructor)
 101                                 ra->destructor(sk);
 102                         sock_put(sk);
 103                         kfree(ra);
 104                         return 0;
 105                 }
 106         }
 107         if (new_ra == NULL) {
 108                 write_unlock_bh(&ip6_ra_lock);
 109                 return -ENOBUFS;
 110         }
 111         new_ra->sk = sk;
 112         new_ra->sel = sel;
 113         new_ra->destructor = destructor;
 114         new_ra->next = ra;
 115         *rap = new_ra;
 116         sock_hold(sk);
 117         write_unlock_bh(&ip6_ra_lock);
 118         return 0;
 119 }
 120
 121
 122 int ipv6_setsockopt(struct sock *sk, int level, int optname, char *optval,
 123                     int optlen)
 124 {
 125         struct ipv6_pinfo *np = &sk->net_pinfo.af_inet6;
 126         int val, valbool;
 127         int retv = -ENOPROTOOPT;
 128
 129         if(level==SOL_IP && sk->type != SOCK_RAW)
 130                 return udp_prot.setsockopt(sk, level, optname, optval, optlen);
 131
 132         if(level!=SOL_IPV6)
 133                 goto out;
 134
 135         if (optval == NULL)
 136                 val=0;
 137         else if (get_user(val, (int *) optval))
 138                 return -EFAULT;
 139
 140         valbool = (val!=0);
 141
 142         lock_sock(sk);
 143
 144         switch (optname) {
 145
 146         case IPV6_ADDRFORM:
 147                 if (val == PF_INET) {
 148                         struct ipv6_txoptions *opt;
 149                         struct sk_buff *pktopt;
 150
 151                         if (sk->protocol != IPPROTO_UDP &&
 152                             sk->protocol != IPPROTO_TCP)
 153                                 break;
 154
 155                         if (sk->state != TCP_ESTABLISHED) {
 156                                 retv = -ENOTCONN;
 157                                 break;
 158                         }
 159
 160                         if (ipv6_only_sock(sk) ||
 161                             !(ipv6_addr_type(&np->daddr) & IPV6_ADDR_MAPPED)) {
 162                                 retv = -EADDRNOTAVAIL;
 163                                 break;
 164                         }
 165
 166                         fl6_free_socklist(sk);
 167                         ipv6_sock_mc_close(sk);
 168
 169                         if (sk->protocol == IPPROTO_TCP) {
 170                                 struct tcp_opt *tp = &(sk->tp_pinfo.af_tcp);
 171
 172                                 local_bh_disable();
 173                                 sock_prot_dec_use(sk->prot);
 174                                 sock_prot_inc_use(&tcp_prot);
 175                                 local_bh_enable();
 176                                 sk->prot = &tcp_prot;
 177                                 tp->af_specific = &ipv4_specific;
 178                                 sk->socket->ops = &inet_stream_ops;
 179                                 sk->family = PF_INET;
 180                                 tcp_sync_mss(sk, tp->pmtu_cookie);
 181                         } else {
 182                                 local_bh_disable();
 183                                 sock_prot_dec_use(sk->prot);
 184                                 sock_prot_inc_use(&udp_prot);
 185                                 local_bh_enable();
 186                                 sk->prot = &udp_prot;
 187                                 sk->socket->ops = &inet_dgram_ops;
 188                                 sk->family = PF_INET;
 189                         }
 190                         opt = xchg(&np->opt, NULL);
 191                         if (opt)
 192                                 sock_kfree_s(sk, opt, opt->tot_len);
 193                         pktopt = xchg(&np->pktoptions, NULL);
 194                         if (pktopt)
 195                                 kfree_skb(pktopt);
 196
 197                         sk->destruct = inet_sock_destruct;
 198 #ifdef INET_REFCNT_DEBUG
 199                         atomic_dec(&inet6_sock_nr);
 200 #endif
 201                         MOD_DEC_USE_COUNT;
 202                         retv = 0;
 203                         break;
 204                 }
 205                 goto e_inval;
 206
 207         case IPV6_V6ONLY:
 208                 if (sk->num)
 209                         goto e_inval;
 210                 np->ipv6only = valbool;
 211                 retv = 0;
 212                 break;
 213
 214         case IPV6_PKTINFO:
 215                 np->rxopt.bits.rxinfo = valbool;
 216                 retv = 0;
 217                 break;
 218
 219         case IPV6_HOPLIMIT:
 220                 np->rxopt.bits.rxhlim = valbool;
 221                 retv = 0;
 222                 break;
 223
 224         case IPV6_RTHDR:
 225                 if (val < 0 || val > 2)
 226                         goto e_inval;
 227                 np->rxopt.bits.srcrt = val;
 228                 retv = 0;
 229                 break;
 230
 231         case IPV6_HOPOPTS:
 232                 np->rxopt.bits.hopopts = valbool;
 233                 retv = 0;
 234                 break;
 235
 236         case IPV6_AUTHHDR:
 237                 np->rxopt.bits.authhdr = valbool;
 238                 retv = 0;
 239                 break;
 240
 241         case IPV6_DSTOPTS:
 242                 np->rxopt.bits.dstopts = valbool;
 243                 retv = 0;
 244                 break;
 245
 246         case IPV6_FLOWINFO:
 247                 np->rxopt.bits.rxflow = valbool;
 248                 retv = 0;
 249                 break;
 250
 251         case IPV6_PKTOPTIONS:
 252         {
 253                 struct ipv6_txoptions *opt = NULL;
 254                 struct msghdr msg;
 255                 struct flowi fl;
 256                 int junk;
 257
 258                 fl.fl6_flowlabel = 0;
 259                 fl.oif = sk->bound_dev_if;
 260
 261                 if (optlen == 0)
 262                         goto update;
 263
 264                 /* 1K is probably excessive
 265                  * 1K is surely not enough, 2K per standard header is 16K.
 266                  */
 267                 retv = -EINVAL;
 268                 if (optlen > 64*1024)
 269                         break;
 270
 271                 opt = sock_kmalloc(sk, sizeof(*opt) + optlen, GFP_KERNEL);
 272                 retv = -ENOBUFS;
 273                 if (opt == NULL)
 274                         break;
 275
 276                 memset(opt, 0, sizeof(*opt));
 277                 opt->tot_len = sizeof(*opt) + optlen;
 278                 retv = -EFAULT;
 279                 if (copy_from_user(opt+1, optval, optlen))
 280                         goto done;
 281
 282                 msg.msg_controllen = optlen;
 283                 msg.msg_control = (void*)(opt+1);
 284
 285                 retv = datagram_send_ctl(&msg, &fl, opt, &junk);
 286                 if (retv)
 287                         goto done;
 288 update:
 289                 retv = 0;
 290                 if (sk->type == SOCK_STREAM) {
 291                         if (opt) {
 292                                 struct tcp_opt *tp = &sk->tp_pinfo.af_tcp;
 293                                 if (!((1<<sk->state)&(TCPF_LISTEN|TCPF_CLOSE))
 294                                     && sk->daddr != LOOPBACK4_IPV6) {
 295                                         tp->ext_header_len = opt->opt_flen + opt->opt_nflen;
 296                                         tcp_sync_mss(sk, tp->pmtu_cookie);
 297                                 }
 298                         }
 299                         opt = xchg(&np->opt, opt);
 300                         sk_dst_reset(sk);
 301                 } else {
 302                         write_lock(&sk->dst_lock);
 303                         opt = xchg(&np->opt, opt);
 304                         write_unlock(&sk->dst_lock);
 305                         sk_dst_reset(sk);
 306                 }
 307
 308 done:
 309                 if (opt)
 310                         sock_kfree_s(sk, opt, opt->tot_len);
 311                 break;
 312         }
 313         case IPV6_UNICAST_HOPS:
 314                 if (val > 255 || val < -1)
 315                         goto e_inval;
 316                 np->hop_limit = val;
 317                 retv = 0;
 318                 break;
 319
 320         case IPV6_MULTICAST_HOPS:
 321                 if (sk->type == SOCK_STREAM)
 322                         goto e_inval;
 323                 if (val > 255 || val < -1)
 324                         goto e_inval;
 325                 np->mcast_hops = val;
 326                 retv = 0;
 327                 break;
 328
 329         case IPV6_MULTICAST_LOOP:
 330                 np->mc_loop = valbool;
 331                 retv = 0;
 332                 break;
 333
 334         case IPV6_MULTICAST_IF:
 335                 if (sk->type == SOCK_STREAM)
 336                         goto e_inval;
 337                 if (sk->bound_dev_if && sk->bound_dev_if != val)
 338                         goto e_inval;
 339
 340                 if (__dev_get_by_index(val) == NULL) {
 341                         retv = -ENODEV;
 342                         break;
 343                 }
 344                 np->mcast_oif = val;
 345                 retv = 0;
 346                 break;
 347         case IPV6_ADD_MEMBERSHIP:
 348         case IPV6_DROP_MEMBERSHIP:
 349         {
 350                 struct ipv6_mreq mreq;
 351
 352                 retv = -EFAULT;
 353                 if (copy_from_user(&mreq, optval, sizeof(struct ipv6_mreq)))
 354                         break;
 355
 356                 if (optname == IPV6_ADD_MEMBERSHIP)
 357                         retv = ipv6_sock_mc_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr);
 358                 else
 359                         retv = ipv6_sock_mc_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr);
 360                 break;
 361         }
 362         case IPV6_ROUTER_ALERT:
 363                 retv = ip6_ra_control(sk, val, NULL);
 364                 break;
 365         case IPV6_MTU_DISCOVER:
 366                 if (val<0 || val>2)
 367                         goto e_inval;
 368                 np->pmtudisc = val;
 369                 retv = 0;
 370                 break;
 371         case IPV6_MTU:
 372                 if (val && val < IPV6_MIN_MTU)
 373                         goto e_inval;
 374                 np->frag_size = val;
 375                 retv = 0;
 376                 break;
 377         case IPV6_RECVERR:
 378                 np->recverr = valbool;
 379                 if (!val)
 380                         skb_queue_purge(&sk->error_queue);
 381                 retv = 0;
 382                 break;
 383         case IPV6_FLOWINFO_SEND:
 384                 np->sndflow = valbool;
 385                 retv = 0;
 386                 break;
 387         case IPV6_FLOWLABEL_MGR:
 388                 retv = ipv6_flowlabel_opt(sk, optval, optlen);
 389                 break;
 390
 391 #ifdef CONFIG_NETFILTER
 392         default:
 393                 retv = nf_setsockopt(sk, PF_INET6, optname, optval,
 394                                             optlen);
 395                 break;
 396 #endif
 397
 398         }
 399         release_sock(sk);
 400
 401 out:
 402         return retv;
 403
 404 e_inval:
 405         release_sock(sk);
 406         return -EINVAL;
 407 }
 408
 409 int ipv6_getsockopt(struct sock *sk, int level, int optname, char *optval,
 410                     int *optlen)
 411 {
 412         struct ipv6_pinfo *np = &sk->net_pinfo.af_inet6;
 413         int len;
 414         int val;
 415
 416         if(level==SOL_IP && sk->type != SOCK_RAW)
 417                 return udp_prot.getsockopt(sk, level, optname, optval, optlen);
 418         if(level!=SOL_IPV6)
 419                 return -ENOPROTOOPT;
 420         if (get_user(len, optlen))
 421                 return -EFAULT;
 422         switch (optname) {
 423         case IPV6_PKTOPTIONS:
 424         {
 425                 struct msghdr msg;
 426                 struct sk_buff *skb;
 427
 428                 if (sk->type != SOCK_STREAM)
 429                         return -ENOPROTOOPT;
 430
 431                 msg.msg_control = optval;
 432                 msg.msg_controllen = len;
 433                 msg.msg_flags = 0;
 434
 435                 lock_sock(sk);
 436                 skb = np->pktoptions;
 437                 if (skb)
 438                         atomic_inc(&skb->users);
 439                 release_sock(sk);
 440
 441                 if (skb) {
 442                         int err = datagram_recv_ctl(sk, &msg, skb);
 443                         kfree_skb(skb);
 444                         if (err)
 445                                 return err;
 446                 } else {
 447                         if (np->rxopt.bits.rxinfo) {
 448                                 struct in6_pktinfo src_info;
 449                                 src_info.ipi6_ifindex = np->mcast_oif;
 450                                 ipv6_addr_copy(&src_info.ipi6_addr, &np->daddr);
 451                                 put_cmsg(&msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info);
 452                         }
 453                         if (np->rxopt.bits.rxhlim) {
 454                                 int hlim = np->mcast_hops;
 455                                 put_cmsg(&msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
 456                         }
 457                 }
 458                 len -= msg.msg_controllen;
 459                 return put_user(len, optlen);
 460         }
 461         case IPV6_MTU:
 462         {
 463                 struct dst_entry *dst;
 464                 val = 0;
 465                 lock_sock(sk);
 466                 dst = sk_dst_get(sk);
 467                 if (dst) {
 468                         val = dst->pmtu;
 469                         dst_release(dst);
 470                 }
 471                 release_sock(sk);
 472                 if (!val)
 473                         return -ENOTCONN;
 474                 break;
 475         }
 476
 477         case IPV6_V6ONLY:
 478                 val = np->ipv6only;
 479                 break;
 480
 481         case IPV6_PKTINFO:
 482                 val = np->rxopt.bits.rxinfo;
 483                 break;
 484
 485         case IPV6_HOPLIMIT:
 486                 val = np->rxopt.bits.rxhlim;
 487                 break;
 488
 489         case IPV6_RTHDR:
 490                 val = np->rxopt.bits.srcrt;
 491                 break;
 492
 493         case IPV6_HOPOPTS:
 494                 val = np->rxopt.bits.hopopts;
 495                 break;
 496
 497         case IPV6_AUTHHDR:
 498                 val = np->rxopt.bits.authhdr;
 499                 break;
 500
 501         case IPV6_DSTOPTS:
 502                 val = np->rxopt.bits.dstopts;
 503                 break;
 504
 505         case IPV6_FLOWINFO:
 506                 val = np->rxopt.bits.rxflow;
 507                 break;
 508
 509         case IPV6_UNICAST_HOPS:
 510                 val = np->hop_limit;
 511                 break;
 512
 513         case IPV6_MULTICAST_HOPS:
 514                 val = np->mcast_hops;
 515                 break;
 516
 517         case IPV6_MULTICAST_LOOP:
 518                 val = np->mc_loop;
 519                 break;
 520
 521         case IPV6_MULTICAST_IF:
 522                 val = np->mcast_oif;
 523                 break;
 524
 525         case IPV6_MTU_DISCOVER:
 526                 val = np->pmtudisc;
 527                 break;
 528
 529         case IPV6_RECVERR:
 530                 val = np->recverr;
 531                 break;
 532
 533         case IPV6_FLOWINFO_SEND:
 534                 val = np->sndflow;
 535                 break;
 536
 537         default:
 538 #ifdef CONFIG_NETFILTER
 539                 lock_sock(sk);
 540                 val = nf_getsockopt(sk, PF_INET6, optname, optval,
 541                                     &len);
 542                 release_sock(sk);
 543                 if (val >= 0)
 544                         val = put_user(len, optlen);
 545                 return val;
 546 #else
 547                 return -EINVAL;
 548 #endif
 549         }
 550         len = min_t(unsigned int, sizeof(int), len);
 551         if(put_user(len, optlen))
 552                 return -EFAULT;
 553         if(copy_to_user(optval,&val,len))
 554                 return -EFAULT;
 555         return 0;
 556 }
 557
 558 #if defined(MODULE) && defined(CONFIG_SYSCTL)
 559
 560 /*
 561  *      sysctl registration functions defined in sysctl_net_ipv6.c
 562  */
 563
 564 extern void ipv6_sysctl_register(void);
 565 extern void ipv6_sysctl_unregister(void);
 566 #endif
 567
 568 void __init ipv6_packet_init(void)
 569 {
 570         dev_add_pack(&ipv6_packet_type);
 571 }
 572
 573 void __init ipv6_netdev_notif_init(void)
 574 {
 575         register_netdevice_notifier(&ipv6_dev_notf);
 576 }
 577
 578 #ifdef MODULE
 579 void ipv6_packet_cleanup(void)
 580 {
 581         dev_remove_pack(&ipv6_packet_type);
 582 }
 583
 584 void ipv6_netdev_notif_cleanup(void)
 585 {
 586         unregister_netdevice_notifier(&ipv6_dev_notf);
 587 }
 588 #endif