net/ipv6/ipv6_sockglue.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *      IPv6 BSD socket options interface
   4  *      Linux INET6 implementation
   5  *
   6  *      Authors:
   7  *      Pedro Roque             <roque@di.fc.ul.pt>
   8  *
   9  *      Based on linux/net/ipv4/ip_sockglue.c
  10  *
  11  *      FIXME: Make the setsockopt code POSIX compliant: That is
  12  *
  13  *      o       Truncate getsockopt returns
  14  *      o       Return an optlen of the truncated length if need be
  15  *
  16  *      Changes:
  17  *      David L Stevens <dlstevens@us.ibm.com>:
  18  *              - added multicast source filtering API for MLDv2
  19  */
  20
  21 #include <linux/module.h>
  22 #include <linux/capability.h>
  23 #include <linux/errno.h>
  24 #include <linux/types.h>
  25 #include <linux/socket.h>
  26 #include <linux/sockios.h>
  27 #include <linux/net.h>
  28 #include <linux/in6.h>
  29 #include <linux/mroute6.h>
  30 #include <linux/netdevice.h>
  31 #include <linux/if_arp.h>
  32 #include <linux/init.h>
  33 #include <linux/sysctl.h>
  34 #include <linux/netfilter.h>
  35 #include <linux/slab.h>
  36
  37 #include <net/sock.h>
  38 #include <net/snmp.h>
  39 #include <net/ipv6.h>
  40 #include <net/ndisc.h>
  41 #include <net/protocol.h>
  42 #include <net/transp_v6.h>
  43 #include <net/ip6_route.h>
  44 #include <net/addrconf.h>
  45 #include <net/inet_common.h>
  46 #include <net/tcp.h>
  47 #include <net/udp.h>
  48 #include <net/udplite.h>
  49 #include <net/xfrm.h>
  50 #include <net/compat.h>
  51 #include <net/seg6.h>
  52
  53 #include <linux/uaccess.h>
  54
  55 struct ip6_ra_chain *ip6_ra_chain;
  56 DEFINE_RWLOCK(ip6_ra_lock);
  57
  58 int ip6_ra_control(struct sock *sk, int sel)
  59 {
  60         struct ip6_ra_chain *ra, *new_ra, **rap;
  61
  62         /* RA packet may be delivered ONLY to IPPROTO_RAW socket */
  63         if (sk->sk_type != SOCK_RAW || inet_sk(sk)->inet_num != IPPROTO_RAW)
  64                 return -ENOPROTOOPT;
  65
  66         new_ra = (sel >= 0) ? kmalloc(sizeof(*new_ra), GFP_KERNEL) : NULL;
  67         if (sel >= 0 && !new_ra)
  68                 return -ENOMEM;
  69
  70         write_lock_bh(&ip6_ra_lock);
  71         for (rap = &ip6_ra_chain; (ra = *rap) != NULL; rap = &ra->next) {
  72                 if (ra->sk == sk) {
  73                         if (sel >= 0) {
  74                                 write_unlock_bh(&ip6_ra_lock);
  75                                 kfree(new_ra);
  76                                 return -EADDRINUSE;
  77                         }
  78
  79                         *rap = ra->next;
  80                         write_unlock_bh(&ip6_ra_lock);
  81
  82                         sock_put(sk);
  83                         kfree(ra);
  84                         return 0;
  85                 }
  86         }
  87         if (!new_ra) {
  88                 write_unlock_bh(&ip6_ra_lock);
  89                 return -ENOBUFS;
  90         }
  91         new_ra->sk = sk;
  92         new_ra->sel = sel;
  93         new_ra->next = ra;
  94         *rap = new_ra;
  95         sock_hold(sk);
  96         write_unlock_bh(&ip6_ra_lock);
  97         return 0;
  98 }
  99
 100 struct ipv6_txoptions *ipv6_update_options(struct sock *sk,
 101                                            struct ipv6_txoptions *opt)
 102 {
 103         if (inet_sk(sk)->is_icsk) {
 104                 if (opt &&
 105                     !((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE)) &&
 106                     inet_sk(sk)->inet_daddr != LOOPBACK4_IPV6) {
 107                         struct inet_connection_sock *icsk = inet_csk(sk);
 108                         icsk->icsk_ext_hdr_len = opt->opt_flen + opt->opt_nflen;
 109                         icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie);
 110                 }
 111         }
 112         opt = xchg((__force struct ipv6_txoptions **)&inet6_sk(sk)->opt,
 113                    opt);
 114         sk_dst_reset(sk);
 115
 116         return opt;
 117 }
 118
 119 static bool setsockopt_needs_rtnl(int optname)
 120 {
 121         switch (optname) {
 122         case IPV6_ADDRFORM:
 123         case IPV6_ADD_MEMBERSHIP:
 124         case IPV6_DROP_MEMBERSHIP:
 125         case IPV6_JOIN_ANYCAST:
 126         case IPV6_LEAVE_ANYCAST:
 127         case MCAST_JOIN_GROUP:
 128         case MCAST_LEAVE_GROUP:
 129         case MCAST_JOIN_SOURCE_GROUP:
 130         case MCAST_LEAVE_SOURCE_GROUP:
 131         case MCAST_BLOCK_SOURCE:
 132         case MCAST_UNBLOCK_SOURCE:
 133         case MCAST_MSFILTER:
 134                 return true;
 135         }
 136         return false;
 137 }
 138
 139 static int copy_group_source_from_sockptr(struct group_source_req *greqs,
 140                 sockptr_t optval, int optlen)
 141 {
 142         if (in_compat_syscall()) {
 143                 struct compat_group_source_req gr32;
 144
 145                 if (optlen < sizeof(gr32))
 146                         return -EINVAL;
 147                 if (copy_from_sockptr(&gr32, optval, sizeof(gr32)))
 148                         return -EFAULT;
 149                 greqs->gsr_interface = gr32.gsr_interface;
 150                 greqs->gsr_group = gr32.gsr_group;
 151                 greqs->gsr_source = gr32.gsr_source;
 152         } else {
 153                 if (optlen < sizeof(*greqs))
 154                         return -EINVAL;
 155                 if (copy_from_sockptr(greqs, optval, sizeof(*greqs)))
 156                         return -EFAULT;
 157         }
 158
 159         return 0;
 160 }
 161
 162 static int do_ipv6_mcast_group_source(struct sock *sk, int optname,
 163                 sockptr_t optval, int optlen)
 164 {
 165         struct group_source_req greqs;
 166         int omode, add;
 167         int ret;
 168
 169         ret = copy_group_source_from_sockptr(&greqs, optval, optlen);
 170         if (ret)
 171                 return ret;
 172
 173         if (greqs.gsr_group.ss_family != AF_INET6 ||
 174             greqs.gsr_source.ss_family != AF_INET6)
 175                 return -EADDRNOTAVAIL;
 176
 177         if (optname == MCAST_BLOCK_SOURCE) {
 178                 omode = MCAST_EXCLUDE;
 179                 add = 1;
 180         } else if (optname == MCAST_UNBLOCK_SOURCE) {
 181                 omode = MCAST_EXCLUDE;
 182                 add = 0;
 183         } else if (optname == MCAST_JOIN_SOURCE_GROUP) {
 184                 struct sockaddr_in6 *psin6;
 185                 int retv;
 186
 187                 psin6 = (struct sockaddr_in6 *)&greqs.gsr_group;
 188                 retv = ipv6_sock_mc_join_ssm(sk, greqs.gsr_interface,
 189                                              &psin6->sin6_addr,
 190                                              MCAST_INCLUDE);
 191                 /* prior join w/ different source is ok */
 192                 if (retv && retv != -EADDRINUSE)
 193                         return retv;
 194                 omode = MCAST_INCLUDE;
 195                 add = 1;
 196         } else /* MCAST_LEAVE_SOURCE_GROUP */ {
 197                 omode = MCAST_INCLUDE;
 198                 add = 0;
 199         }
 200         return ip6_mc_source(add, omode, sk, &greqs);
 201 }
 202
 203 static int ipv6_set_mcast_msfilter(struct sock *sk, sockptr_t optval,
 204                 int optlen)
 205 {
 206         struct group_filter *gsf;
 207         int ret;
 208
 209         if (optlen < GROUP_FILTER_SIZE(0))
 210                 return -EINVAL;
 211         if (optlen > READ_ONCE(sysctl_optmem_max))
 212                 return -ENOBUFS;
 213
 214         gsf = memdup_sockptr(optval, optlen);
 215         if (IS_ERR(gsf))
 216                 return PTR_ERR(gsf);
 217
 218         /* numsrc >= (4G-140)/128 overflow in 32 bits */
 219         ret = -ENOBUFS;
 220         if (gsf->gf_numsrc >= 0x1ffffffU ||
 221             gsf->gf_numsrc > sysctl_mld_max_msf)
 222                 goto out_free_gsf;
 223
 224         ret = -EINVAL;
 225         if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen)
 226                 goto out_free_gsf;
 227
 228         ret = ip6_mc_msfilter(sk, gsf, gsf->gf_slist_flex);
 229 out_free_gsf:
 230         kfree(gsf);
 231         return ret;
 232 }
 233
 234 static int compat_ipv6_set_mcast_msfilter(struct sock *sk, sockptr_t optval,
 235                 int optlen)
 236 {
 237         const int size0 = offsetof(struct compat_group_filter, gf_slist_flex);
 238         struct compat_group_filter *gf32;
 239         void *p;
 240         int ret;
 241         int n;
 242
 243         if (optlen < size0)
 244                 return -EINVAL;
 245         if (optlen > READ_ONCE(sysctl_optmem_max) - 4)
 246                 return -ENOBUFS;
 247
 248         p = kmalloc(optlen + 4, GFP_KERNEL);
 249         if (!p)
 250                 return -ENOMEM;
 251
 252         gf32 = p + 4; /* we want ->gf_group and ->gf_slist_flex aligned */
 253         ret = -EFAULT;
 254         if (copy_from_sockptr(gf32, optval, optlen))
 255                 goto out_free_p;
 256
 257         /* numsrc >= (4G-140)/128 overflow in 32 bits */
 258         ret = -ENOBUFS;
 259         n = gf32->gf_numsrc;
 260         if (n >= 0x1ffffffU || n > sysctl_mld_max_msf)
 261                 goto out_free_p;
 262
 263         ret = -EINVAL;
 264         if (offsetof(struct compat_group_filter, gf_slist_flex[n]) > optlen)
 265                 goto out_free_p;
 266
 267         ret = ip6_mc_msfilter(sk, &(struct group_filter){
 268                         .gf_interface = gf32->gf_interface,
 269                         .gf_group = gf32->gf_group,
 270                         .gf_fmode = gf32->gf_fmode,
 271                         .gf_numsrc = gf32->gf_numsrc}, gf32->gf_slist_flex);
 272
 273 out_free_p:
 274         kfree(p);
 275         return ret;
 276 }
 277
 278 static int ipv6_mcast_join_leave(struct sock *sk, int optname,
 279                 sockptr_t optval, int optlen)
 280 {
 281         struct sockaddr_in6 *psin6;
 282         struct group_req greq;
 283
 284         if (optlen < sizeof(greq))
 285                 return -EINVAL;
 286         if (copy_from_sockptr(&greq, optval, sizeof(greq)))
 287                 return -EFAULT;
 288
 289         if (greq.gr_group.ss_family != AF_INET6)
 290                 return -EADDRNOTAVAIL;
 291         psin6 = (struct sockaddr_in6 *)&greq.gr_group;
 292         if (optname == MCAST_JOIN_GROUP)
 293                 return ipv6_sock_mc_join(sk, greq.gr_interface,
 294                                          &psin6->sin6_addr);
 295         return ipv6_sock_mc_drop(sk, greq.gr_interface, &psin6->sin6_addr);
 296 }
 297
 298 static int compat_ipv6_mcast_join_leave(struct sock *sk, int optname,
 299                 sockptr_t optval, int optlen)
 300 {
 301         struct compat_group_req gr32;
 302         struct sockaddr_in6 *psin6;
 303
 304         if (optlen < sizeof(gr32))
 305                 return -EINVAL;
 306         if (copy_from_sockptr(&gr32, optval, sizeof(gr32)))
 307                 return -EFAULT;
 308
 309         if (gr32.gr_group.ss_family != AF_INET6)
 310                 return -EADDRNOTAVAIL;
 311         psin6 = (struct sockaddr_in6 *)&gr32.gr_group;
 312         if (optname == MCAST_JOIN_GROUP)
 313                 return ipv6_sock_mc_join(sk, gr32.gr_interface,
 314                                         &psin6->sin6_addr);
 315         return ipv6_sock_mc_drop(sk, gr32.gr_interface, &psin6->sin6_addr);
 316 }
 317
 318 static int ipv6_set_opt_hdr(struct sock *sk, int optname, sockptr_t optval,
 319                 int optlen)
 320 {
 321         struct ipv6_pinfo *np = inet6_sk(sk);
 322         struct ipv6_opt_hdr *new = NULL;
 323         struct net *net = sock_net(sk);
 324         struct ipv6_txoptions *opt;
 325         int err;
 326
 327         /* hop-by-hop / destination options are privileged option */
 328         if (optname != IPV6_RTHDR && !ns_capable(net->user_ns, CAP_NET_RAW))
 329                 return -EPERM;
 330
 331         /* remove any sticky options header with a zero option
 332          * length, per RFC3542.
 333          */
 334         if (optlen > 0) {
 335                 if (sockptr_is_null(optval))
 336                         return -EINVAL;
 337                 if (optlen < sizeof(struct ipv6_opt_hdr) ||
 338                     optlen & 0x7 ||
 339                     optlen > 8 * 255)
 340                         return -EINVAL;
 341
 342                 new = memdup_sockptr(optval, optlen);
 343                 if (IS_ERR(new))
 344                         return PTR_ERR(new);
 345                 if (unlikely(ipv6_optlen(new) > optlen)) {
 346                         kfree(new);
 347                         return -EINVAL;
 348                 }
 349         }
 350
 351         opt = rcu_dereference_protected(np->opt, lockdep_sock_is_held(sk));
 352         opt = ipv6_renew_options(sk, opt, optname, new);
 353         kfree(new);
 354         if (IS_ERR(opt))
 355                 return PTR_ERR(opt);
 356
 357         /* routing header option needs extra check */
 358         err = -EINVAL;
 359         if (optname == IPV6_RTHDR && opt && opt->srcrt) {
 360                 struct ipv6_rt_hdr *rthdr = opt->srcrt;
 361                 switch (rthdr->type) {
 362 #if IS_ENABLED(CONFIG_IPV6_MIP6)
 363                 case IPV6_SRCRT_TYPE_2:
 364                         if (rthdr->hdrlen != 2 || rthdr->segments_left != 1)
 365                                 goto sticky_done;
 366                         break;
 367 #endif
 368                 case IPV6_SRCRT_TYPE_4:
 369                 {
 370                         struct ipv6_sr_hdr *srh =
 371                                 (struct ipv6_sr_hdr *)opt->srcrt;
 372
 373                         if (!seg6_validate_srh(srh, optlen, false))
 374                                 goto sticky_done;
 375                         break;
 376                 }
 377                 default:
 378                         goto sticky_done;
 379                 }
 380         }
 381
 382         err = 0;
 383         opt = ipv6_update_options(sk, opt);
 384 sticky_done:
 385         if (opt) {
 386                 atomic_sub(opt->tot_len, &sk->sk_omem_alloc);
 387                 txopt_put(opt);
 388         }
 389         return err;
 390 }
 391
 392 static int do_ipv6_setsockopt(struct sock *sk, int level, int optname,
 393                    sockptr_t optval, unsigned int optlen)
 394 {
 395         struct ipv6_pinfo *np = inet6_sk(sk);
 396         struct net *net = sock_net(sk);
 397         int val, valbool;
 398         int retv = -ENOPROTOOPT;
 399         bool needs_rtnl = setsockopt_needs_rtnl(optname);
 400
 401         if (sockptr_is_null(optval))
 402                 val = 0;
 403         else {
 404                 if (optlen >= sizeof(int)) {
 405                         if (copy_from_sockptr(&val, optval, sizeof(val)))
 406                                 return -EFAULT;
 407                 } else
 408                         val = 0;
 409         }
 410
 411         valbool = (val != 0);
 412
 413         if (ip6_mroute_opt(optname))
 414                 return ip6_mroute_setsockopt(sk, optname, optval, optlen);
 415
 416         if (needs_rtnl)
 417                 rtnl_lock();
 418         lock_sock(sk);
 419
 420         /* Another thread has converted the socket into IPv4 with
 421          * IPV6_ADDRFORM concurrently.
 422          */
 423         if (unlikely(sk->sk_family != AF_INET6))
 424                 goto unlock;
 425
 426         switch (optname) {
 427
 428         case IPV6_ADDRFORM:
 429                 if (optlen < sizeof(int))
 430                         goto e_inval;
 431                 if (val == PF_INET) {
 432                         if (sk->sk_type == SOCK_RAW)
 433                                 break;
 434
 435                         if (sk->sk_protocol == IPPROTO_UDP ||
 436                             sk->sk_protocol == IPPROTO_UDPLITE) {
 437                                 struct udp_sock *up = udp_sk(sk);
 438                                 if (up->pending == AF_INET6) {
 439                                         retv = -EBUSY;
 440                                         break;
 441                                 }
 442                         } else if (sk->sk_protocol == IPPROTO_TCP) {
 443                                 if (sk->sk_prot != &tcpv6_prot) {
 444                                         retv = -EBUSY;
 445                                         break;
 446                                 }
 447                         } else {
 448                                 break;
 449                         }
 450
 451                         if (sk->sk_state != TCP_ESTABLISHED) {
 452                                 retv = -ENOTCONN;
 453                                 break;
 454                         }
 455
 456                         if (ipv6_only_sock(sk) ||
 457                             !ipv6_addr_v4mapped(&sk->sk_v6_daddr)) {
 458                                 retv = -EADDRNOTAVAIL;
 459                                 break;
 460                         }
 461
 462                         __ipv6_sock_mc_close(sk);
 463                         __ipv6_sock_ac_close(sk);
 464
 465                         /*
 466                          * Sock is moving from IPv6 to IPv4 (sk_prot), so
 467                          * remove it from the refcnt debug socks count in the
 468                          * original family...
 469                          */
 470                         sk_refcnt_debug_dec(sk);
 471
 472                         if (sk->sk_protocol == IPPROTO_TCP) {
 473                                 struct inet_connection_sock *icsk = inet_csk(sk);
 474                                 local_bh_disable();
 475                                 sock_prot_inuse_add(net, sk->sk_prot, -1);
 476                                 sock_prot_inuse_add(net, &tcp_prot, 1);
 477                                 local_bh_enable();
 478                                 sk->sk_prot = &tcp_prot;
 479                                 icsk->icsk_af_ops = &ipv4_specific;
 480                                 sk->sk_socket->ops = &inet_stream_ops;
 481                                 sk->sk_family = PF_INET;
 482                                 tcp_sync_mss(sk, icsk->icsk_pmtu_cookie);
 483                         } else {
 484                                 struct proto *prot = &udp_prot;
 485
 486                                 if (sk->sk_protocol == IPPROTO_UDPLITE)
 487                                         prot = &udplite_prot;
 488                                 local_bh_disable();
 489                                 sock_prot_inuse_add(net, sk->sk_prot, -1);
 490                                 sock_prot_inuse_add(net, prot, 1);
 491                                 local_bh_enable();
 492                                 sk->sk_prot = prot;
 493                                 sk->sk_socket->ops = &inet_dgram_ops;
 494                                 sk->sk_family = PF_INET;
 495                         }
 496
 497                         /* Disable all options not to allocate memory anymore,
 498                          * but there is still a race.  See the lockless path
 499                          * in udpv6_sendmsg() and ipv6_local_rxpmtu().
 500                          */
 501                         np->rxopt.all = 0;
 502
 503                         inet6_cleanup_sock(sk);
 504
 505                         /*
 506                          * ... and add it to the refcnt debug socks count
 507                          * in the new family. -acme
 508                          */
 509                         sk_refcnt_debug_inc(sk);
 510                         module_put(THIS_MODULE);
 511                         retv = 0;
 512                         break;
 513                 }
 514                 goto e_inval;
 515
 516         case IPV6_V6ONLY:
 517                 if (optlen < sizeof(int) ||
 518                     inet_sk(sk)->inet_num)
 519                         goto e_inval;
 520                 sk->sk_ipv6only = valbool;
 521                 retv = 0;
 522                 break;
 523
 524         case IPV6_RECVPKTINFO:
 525                 if (optlen < sizeof(int))
 526                         goto e_inval;
 527                 np->rxopt.bits.rxinfo = valbool;
 528                 retv = 0;
 529                 break;
 530
 531         case IPV6_2292PKTINFO:
 532                 if (optlen < sizeof(int))
 533                         goto e_inval;
 534                 np->rxopt.bits.rxoinfo = valbool;
 535                 retv = 0;
 536                 break;
 537
 538         case IPV6_RECVHOPLIMIT:
 539                 if (optlen < sizeof(int))
 540                         goto e_inval;
 541                 np->rxopt.bits.rxhlim = valbool;
 542                 retv = 0;
 543                 break;
 544
 545         case IPV6_2292HOPLIMIT:
 546                 if (optlen < sizeof(int))
 547                         goto e_inval;
 548                 np->rxopt.bits.rxohlim = valbool;
 549                 retv = 0;
 550                 break;
 551
 552         case IPV6_RECVRTHDR:
 553                 if (optlen < sizeof(int))
 554                         goto e_inval;
 555                 np->rxopt.bits.srcrt = valbool;
 556                 retv = 0;
 557                 break;
 558
 559         case IPV6_2292RTHDR:
 560                 if (optlen < sizeof(int))
 561                         goto e_inval;
 562                 np->rxopt.bits.osrcrt = valbool;
 563                 retv = 0;
 564                 break;
 565
 566         case IPV6_RECVHOPOPTS:
 567                 if (optlen < sizeof(int))
 568                         goto e_inval;
 569                 np->rxopt.bits.hopopts = valbool;
 570                 retv = 0;
 571                 break;
 572
 573         case IPV6_2292HOPOPTS:
 574                 if (optlen < sizeof(int))
 575                         goto e_inval;
 576                 np->rxopt.bits.ohopopts = valbool;
 577                 retv = 0;
 578                 break;
 579
 580         case IPV6_RECVDSTOPTS:
 581                 if (optlen < sizeof(int))
 582                         goto e_inval;
 583                 np->rxopt.bits.dstopts = valbool;
 584                 retv = 0;
 585                 break;
 586
 587         case IPV6_2292DSTOPTS:
 588                 if (optlen < sizeof(int))
 589                         goto e_inval;
 590                 np->rxopt.bits.odstopts = valbool;
 591                 retv = 0;
 592                 break;
 593
 594         case IPV6_TCLASS:
 595                 if (optlen < sizeof(int))
 596                         goto e_inval;
 597                 if (val < -1 || val > 0xff)
 598                         goto e_inval;
 599                 /* RFC 3542, 6.5: default traffic class of 0x0 */
 600                 if (val == -1)
 601                         val = 0;
 602                 np->tclass = val;
 603                 retv = 0;
 604                 break;
 605
 606         case IPV6_RECVTCLASS:
 607                 if (optlen < sizeof(int))
 608                         goto e_inval;
 609                 np->rxopt.bits.rxtclass = valbool;
 610                 retv = 0;
 611                 break;
 612
 613         case IPV6_FLOWINFO:
 614                 if (optlen < sizeof(int))
 615                         goto e_inval;
 616                 np->rxopt.bits.rxflow = valbool;
 617                 retv = 0;
 618                 break;
 619
 620         case IPV6_RECVPATHMTU:
 621                 if (optlen < sizeof(int))
 622                         goto e_inval;
 623                 np->rxopt.bits.rxpmtu = valbool;
 624                 retv = 0;
 625                 break;
 626
 627         case IPV6_TRANSPARENT:
 628                 if (valbool && !ns_capable(net->user_ns, CAP_NET_RAW) &&
 629                     !ns_capable(net->user_ns, CAP_NET_ADMIN)) {
 630                         retv = -EPERM;
 631                         break;
 632                 }
 633                 if (optlen < sizeof(int))
 634                         goto e_inval;
 635                 /* we don't have a separate transparent bit for IPV6 we use the one in the IPv4 socket */
 636                 inet_sk(sk)->transparent = valbool;
 637                 retv = 0;
 638                 break;
 639
 640         case IPV6_FREEBIND:
 641                 if (optlen < sizeof(int))
 642                         goto e_inval;
 643                 /* we also don't have a separate freebind bit for IPV6 */
 644                 inet_sk(sk)->freebind = valbool;
 645                 retv = 0;
 646                 break;
 647
 648         case IPV6_RECVORIGDSTADDR:
 649                 if (optlen < sizeof(int))
 650                         goto e_inval;
 651                 np->rxopt.bits.rxorigdstaddr = valbool;
 652                 retv = 0;
 653                 break;
 654
 655         case IPV6_HOPOPTS:
 656         case IPV6_RTHDRDSTOPTS:
 657         case IPV6_RTHDR:
 658         case IPV6_DSTOPTS:
 659                 retv = ipv6_set_opt_hdr(sk, optname, optval, optlen);
 660                 break;
 661
 662         case IPV6_PKTINFO:
 663         {
 664                 struct in6_pktinfo pkt;
 665
 666                 if (optlen == 0)
 667                         goto e_inval;
 668                 else if (optlen < sizeof(struct in6_pktinfo) ||
 669                          sockptr_is_null(optval))
 670                         goto e_inval;
 671
 672                 if (copy_from_sockptr(&pkt, optval, sizeof(pkt))) {
 673                         retv = -EFAULT;
 674                         break;
 675                 }
 676                 if (!sk_dev_equal_l3scope(sk, pkt.ipi6_ifindex))
 677                         goto e_inval;
 678
 679                 np->sticky_pktinfo.ipi6_ifindex = pkt.ipi6_ifindex;
 680                 np->sticky_pktinfo.ipi6_addr = pkt.ipi6_addr;
 681                 retv = 0;
 682                 break;
 683         }
 684
 685         case IPV6_2292PKTOPTIONS:
 686         {
 687                 struct ipv6_txoptions *opt = NULL;
 688                 struct msghdr msg;
 689                 struct flowi6 fl6;
 690                 struct ipcm6_cookie ipc6;
 691
 692                 memset(&fl6, 0, sizeof(fl6));
 693                 fl6.flowi6_oif = sk->sk_bound_dev_if;
 694                 fl6.flowi6_mark = sk->sk_mark;
 695
 696                 if (optlen == 0)
 697                         goto update;
 698
 699                 /* 1K is probably excessive
 700                  * 1K is surely not enough, 2K per standard header is 16K.
 701                  */
 702                 retv = -EINVAL;
 703                 if (optlen > 64*1024)
 704                         break;
 705
 706                 opt = sock_kmalloc(sk, sizeof(*opt) + optlen, GFP_KERNEL);
 707                 retv = -ENOBUFS;
 708                 if (!opt)
 709                         break;
 710
 711                 memset(opt, 0, sizeof(*opt));
 712                 refcount_set(&opt->refcnt, 1);
 713                 opt->tot_len = sizeof(*opt) + optlen;
 714                 retv = -EFAULT;
 715                 if (copy_from_sockptr(opt + 1, optval, optlen))
 716                         goto done;
 717
 718                 msg.msg_controllen = optlen;
 719                 msg.msg_control = (void *)(opt+1);
 720                 ipc6.opt = opt;
 721
 722                 retv = ip6_datagram_send_ctl(net, sk, &msg, &fl6, &ipc6);
 723                 if (retv)
 724                         goto done;
 725 update:
 726                 retv = 0;
 727                 opt = ipv6_update_options(sk, opt);
 728 done:
 729                 if (opt) {
 730                         atomic_sub(opt->tot_len, &sk->sk_omem_alloc);
 731                         txopt_put(opt);
 732                 }
 733                 break;
 734         }
 735         case IPV6_UNICAST_HOPS:
 736                 if (optlen < sizeof(int))
 737                         goto e_inval;
 738                 if (val > 255 || val < -1)
 739                         goto e_inval;
 740                 np->hop_limit = val;
 741                 retv = 0;
 742                 break;
 743
 744         case IPV6_MULTICAST_HOPS:
 745                 if (sk->sk_type == SOCK_STREAM)
 746                         break;
 747                 if (optlen < sizeof(int))
 748                         goto e_inval;
 749                 if (val > 255 || val < -1)
 750                         goto e_inval;
 751                 np->mcast_hops = (val == -1 ? IPV6_DEFAULT_MCASTHOPS : val);
 752                 retv = 0;
 753                 break;
 754
 755         case IPV6_MULTICAST_LOOP:
 756                 if (optlen < sizeof(int))
 757                         goto e_inval;
 758                 if (val != valbool)
 759                         goto e_inval;
 760                 np->mc_loop = valbool;
 761                 retv = 0;
 762                 break;
 763
 764         case IPV6_UNICAST_IF:
 765         {
 766                 struct net_device *dev = NULL;
 767                 int ifindex;
 768
 769                 if (optlen != sizeof(int))
 770                         goto e_inval;
 771
 772                 ifindex = (__force int)ntohl((__force __be32)val);
 773                 if (ifindex == 0) {
 774                         np->ucast_oif = 0;
 775                         retv = 0;
 776                         break;
 777                 }
 778
 779                 dev = dev_get_by_index(net, ifindex);
 780                 retv = -EADDRNOTAVAIL;
 781                 if (!dev)
 782                         break;
 783                 dev_put(dev);
 784
 785                 retv = -EINVAL;
 786                 if (sk->sk_bound_dev_if)
 787                         break;
 788
 789                 np->ucast_oif = ifindex;
 790                 retv = 0;
 791                 break;
 792         }
 793
 794         case IPV6_MULTICAST_IF:
 795                 if (sk->sk_type == SOCK_STREAM)
 796                         break;
 797                 if (optlen < sizeof(int))
 798                         goto e_inval;
 799
 800                 if (val) {
 801                         struct net_device *dev;
 802                         int midx;
 803
 804                         rcu_read_lock();
 805
 806                         dev = dev_get_by_index_rcu(net, val);
 807                         if (!dev) {
 808                                 rcu_read_unlock();
 809                                 retv = -ENODEV;
 810                                 break;
 811                         }
 812                         midx = l3mdev_master_ifindex_rcu(dev);
 813
 814                         rcu_read_unlock();
 815
 816                         if (sk->sk_bound_dev_if &&
 817                             sk->sk_bound_dev_if != val &&
 818                             (!midx || midx != sk->sk_bound_dev_if))
 819                                 goto e_inval;
 820                 }
 821                 np->mcast_oif = val;
 822                 retv = 0;
 823                 break;
 824         case IPV6_ADD_MEMBERSHIP:
 825         case IPV6_DROP_MEMBERSHIP:
 826         {
 827                 struct ipv6_mreq mreq;
 828
 829                 if (optlen < sizeof(struct ipv6_mreq))
 830                         goto e_inval;
 831
 832                 retv = -EPROTO;
 833                 if (inet_sk(sk)->is_icsk)
 834                         break;
 835
 836                 retv = -EFAULT;
 837                 if (copy_from_sockptr(&mreq, optval, sizeof(struct ipv6_mreq)))
 838                         break;
 839
 840                 if (optname == IPV6_ADD_MEMBERSHIP)
 841                         retv = ipv6_sock_mc_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr);
 842                 else
 843                         retv = ipv6_sock_mc_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr);
 844                 break;
 845         }
 846         case IPV6_JOIN_ANYCAST:
 847         case IPV6_LEAVE_ANYCAST:
 848         {
 849                 struct ipv6_mreq mreq;
 850
 851                 if (optlen < sizeof(struct ipv6_mreq))
 852                         goto e_inval;
 853
 854                 retv = -EFAULT;
 855                 if (copy_from_sockptr(&mreq, optval, sizeof(struct ipv6_mreq)))
 856                         break;
 857
 858                 if (optname == IPV6_JOIN_ANYCAST)
 859                         retv = ipv6_sock_ac_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_acaddr);
 860                 else
 861                         retv = ipv6_sock_ac_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_acaddr);
 862                 break;
 863         }
 864         case IPV6_MULTICAST_ALL:
 865                 if (optlen < sizeof(int))
 866                         goto e_inval;
 867                 np->mc_all = valbool;
 868                 retv = 0;
 869                 break;
 870
 871         case MCAST_JOIN_GROUP:
 872         case MCAST_LEAVE_GROUP:
 873                 if (in_compat_syscall())
 874                         retv = compat_ipv6_mcast_join_leave(sk, optname, optval,
 875                                                             optlen);
 876                 else
 877                         retv = ipv6_mcast_join_leave(sk, optname, optval,
 878                                                      optlen);
 879                 break;
 880         case MCAST_JOIN_SOURCE_GROUP:
 881         case MCAST_LEAVE_SOURCE_GROUP:
 882         case MCAST_BLOCK_SOURCE:
 883         case MCAST_UNBLOCK_SOURCE:
 884                 retv = do_ipv6_mcast_group_source(sk, optname, optval, optlen);
 885                 break;
 886         case MCAST_MSFILTER:
 887                 if (in_compat_syscall())
 888                         retv = compat_ipv6_set_mcast_msfilter(sk, optval,
 889                                                               optlen);
 890                 else
 891                         retv = ipv6_set_mcast_msfilter(sk, optval, optlen);
 892                 break;
 893         case IPV6_ROUTER_ALERT:
 894                 if (optlen < sizeof(int))
 895                         goto e_inval;
 896                 retv = ip6_ra_control(sk, val);
 897                 break;
 898         case IPV6_ROUTER_ALERT_ISOLATE:
 899                 if (optlen < sizeof(int))
 900                         goto e_inval;
 901                 np->rtalert_isolate = valbool;
 902                 retv = 0;
 903                 break;
 904         case IPV6_MTU_DISCOVER:
 905                 if (optlen < sizeof(int))
 906                         goto e_inval;
 907                 if (val < IPV6_PMTUDISC_DONT || val > IPV6_PMTUDISC_OMIT)
 908                         goto e_inval;
 909                 np->pmtudisc = val;
 910                 retv = 0;
 911                 break;
 912         case IPV6_MTU:
 913                 if (optlen < sizeof(int))
 914                         goto e_inval;
 915                 if (val && val < IPV6_MIN_MTU)
 916                         goto e_inval;
 917                 np->frag_size = val;
 918                 retv = 0;
 919                 break;
 920         case IPV6_RECVERR:
 921                 if (optlen < sizeof(int))
 922                         goto e_inval;
 923                 np->recverr = valbool;
 924                 if (!val)
 925                         skb_queue_purge(&sk->sk_error_queue);
 926                 retv = 0;
 927                 break;
 928         case IPV6_FLOWINFO_SEND:
 929                 if (optlen < sizeof(int))
 930                         goto e_inval;
 931                 np->sndflow = valbool;
 932                 retv = 0;
 933                 break;
 934         case IPV6_FLOWLABEL_MGR:
 935                 retv = ipv6_flowlabel_opt(sk, optval, optlen);
 936                 break;
 937         case IPV6_IPSEC_POLICY:
 938         case IPV6_XFRM_POLICY:
 939                 retv = -EPERM;
 940                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 941                         break;
 942                 retv = xfrm_user_policy(sk, optname, optval, optlen);
 943                 break;
 944
 945         case IPV6_ADDR_PREFERENCES:
 946                 if (optlen < sizeof(int))
 947                         goto e_inval;
 948                 retv = __ip6_sock_set_addr_preferences(sk, val);
 949                 break;
 950         case IPV6_MINHOPCOUNT:
 951                 if (optlen < sizeof(int))
 952                         goto e_inval;
 953                 if (val < 0 || val > 255)
 954                         goto e_inval;
 955                 np->min_hopcount = val;
 956                 retv = 0;
 957                 break;
 958         case IPV6_DONTFRAG:
 959                 np->dontfrag = valbool;
 960                 retv = 0;
 961                 break;
 962         case IPV6_AUTOFLOWLABEL:
 963                 np->autoflowlabel = valbool;
 964                 np->autoflowlabel_set = 1;
 965                 retv = 0;
 966                 break;
 967         case IPV6_RECVFRAGSIZE:
 968                 np->rxopt.bits.recvfragsize = valbool;
 969                 retv = 0;
 970                 break;
 971         case IPV6_RECVERR_RFC4884:
 972                 if (optlen < sizeof(int))
 973                         goto e_inval;
 974                 if (val < 0 || val > 1)
 975                         goto e_inval;
 976                 np->recverr_rfc4884 = valbool;
 977                 retv = 0;
 978                 break;
 979         }
 980
 981 unlock:
 982         release_sock(sk);
 983         if (needs_rtnl)
 984                 rtnl_unlock();
 985
 986         return retv;
 987
 988 e_inval:
 989         release_sock(sk);
 990         if (needs_rtnl)
 991                 rtnl_unlock();
 992         return -EINVAL;
 993 }
 994
 995 int ipv6_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
 996                     unsigned int optlen)
 997 {
 998         int err;
 999
1000         if (level == SOL_IP && sk->sk_type != SOCK_RAW)
1001                 return udp_prot.setsockopt(sk, level, optname, optval, optlen);
1002
1003         if (level != SOL_IPV6)
1004                 return -ENOPROTOOPT;
1005
1006         err = do_ipv6_setsockopt(sk, level, optname, optval, optlen);
1007 #ifdef CONFIG_NETFILTER
1008         /* we need to exclude all possible ENOPROTOOPTs except default case */
1009         if (err == -ENOPROTOOPT && optname != IPV6_IPSEC_POLICY &&
1010                         optname != IPV6_XFRM_POLICY)
1011                 err = nf_setsockopt(sk, PF_INET6, optname, optval, optlen);
1012 #endif
1013         return err;
1014 }
1015 EXPORT_SYMBOL(ipv6_setsockopt);
1016
1017 static int ipv6_getsockopt_sticky(struct sock *sk, struct ipv6_txoptions *opt,
1018                                   int optname, char __user *optval, int len)
1019 {
1020         struct ipv6_opt_hdr *hdr;
1021
1022         if (!opt)
1023                 return 0;
1024
1025         switch (optname) {
1026         case IPV6_HOPOPTS:
1027                 hdr = opt->hopopt;
1028                 break;
1029         case IPV6_RTHDRDSTOPTS:
1030                 hdr = opt->dst0opt;
1031                 break;
1032         case IPV6_RTHDR:
1033                 hdr = (struct ipv6_opt_hdr *)opt->srcrt;
1034                 break;
1035         case IPV6_DSTOPTS:
1036                 hdr = opt->dst1opt;
1037                 break;
1038         default:
1039                 return -EINVAL; /* should not happen */
1040         }
1041
1042         if (!hdr)
1043                 return 0;
1044
1045         len = min_t(unsigned int, len, ipv6_optlen(hdr));
1046         if (copy_to_user(optval, hdr, len))
1047                 return -EFAULT;
1048         return len;
1049 }
1050
1051 static int ipv6_get_msfilter(struct sock *sk, void __user *optval,
1052                 int __user *optlen, int len)
1053 {
1054         const int size0 = offsetof(struct group_filter, gf_slist_flex);
1055         struct group_filter __user *p = optval;
1056         struct group_filter gsf;
1057         int num;
1058         int err;
1059
1060         if (len < size0)
1061                 return -EINVAL;
1062         if (copy_from_user(&gsf, p, size0))
1063                 return -EFAULT;
1064         if (gsf.gf_group.ss_family != AF_INET6)
1065                 return -EADDRNOTAVAIL;
1066         num = gsf.gf_numsrc;
1067         lock_sock(sk);
1068         err = ip6_mc_msfget(sk, &gsf, p->gf_slist_flex);
1069         if (!err) {
1070                 if (num > gsf.gf_numsrc)
1071                         num = gsf.gf_numsrc;
1072                 if (put_user(GROUP_FILTER_SIZE(num), optlen) ||
1073                     copy_to_user(p, &gsf, size0))
1074                         err = -EFAULT;
1075         }
1076         release_sock(sk);
1077         return err;
1078 }
1079
1080 static int compat_ipv6_get_msfilter(struct sock *sk, void __user *optval,
1081                 int __user *optlen)
1082 {
1083         const int size0 = offsetof(struct compat_group_filter, gf_slist_flex);
1084         struct compat_group_filter __user *p = optval;
1085         struct compat_group_filter gf32;
1086         struct group_filter gf;
1087         int len, err;
1088         int num;
1089
1090         if (get_user(len, optlen))
1091                 return -EFAULT;
1092         if (len < size0)
1093                 return -EINVAL;
1094
1095         if (copy_from_user(&gf32, p, size0))
1096                 return -EFAULT;
1097         gf.gf_interface = gf32.gf_interface;
1098         gf.gf_fmode = gf32.gf_fmode;
1099         num = gf.gf_numsrc = gf32.gf_numsrc;
1100         gf.gf_group = gf32.gf_group;
1101
1102         if (gf.gf_group.ss_family != AF_INET6)
1103                 return -EADDRNOTAVAIL;
1104
1105         lock_sock(sk);
1106         err = ip6_mc_msfget(sk, &gf, p->gf_slist_flex);
1107         release_sock(sk);
1108         if (err)
1109                 return err;
1110         if (num > gf.gf_numsrc)
1111                 num = gf.gf_numsrc;
1112         len = GROUP_FILTER_SIZE(num) - (sizeof(gf)-sizeof(gf32));
1113         if (put_user(len, optlen) ||
1114             put_user(gf.gf_fmode, &p->gf_fmode) ||
1115             put_user(gf.gf_numsrc, &p->gf_numsrc))
1116                 return -EFAULT;
1117         return 0;
1118 }
1119
1120 static int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
1121                     char __user *optval, int __user *optlen, unsigned int flags)
1122 {
1123         struct ipv6_pinfo *np = inet6_sk(sk);
1124         int len;
1125         int val;
1126
1127         if (ip6_mroute_opt(optname))
1128                 return ip6_mroute_getsockopt(sk, optname, optval, optlen);
1129
1130         if (get_user(len, optlen))
1131                 return -EFAULT;
1132         switch (optname) {
1133         case IPV6_ADDRFORM:
1134                 if (sk->sk_protocol != IPPROTO_UDP &&
1135                     sk->sk_protocol != IPPROTO_UDPLITE &&
1136                     sk->sk_protocol != IPPROTO_TCP)
1137                         return -ENOPROTOOPT;
1138                 if (sk->sk_state != TCP_ESTABLISHED)
1139                         return -ENOTCONN;
1140                 val = sk->sk_family;
1141                 break;
1142         case MCAST_MSFILTER:
1143                 if (in_compat_syscall())
1144                         return compat_ipv6_get_msfilter(sk, optval, optlen);
1145                 return ipv6_get_msfilter(sk, optval, optlen, len);
1146         case IPV6_2292PKTOPTIONS:
1147         {
1148                 struct msghdr msg;
1149                 struct sk_buff *skb;
1150
1151                 if (sk->sk_type != SOCK_STREAM)
1152                         return -ENOPROTOOPT;
1153
1154                 msg.msg_control_user = optval;
1155                 msg.msg_controllen = len;
1156                 msg.msg_flags = flags;
1157                 msg.msg_control_is_user = true;
1158
1159                 lock_sock(sk);
1160                 skb = np->pktoptions;
1161                 if (skb)
1162                         ip6_datagram_recv_ctl(sk, &msg, skb);
1163                 release_sock(sk);
1164                 if (!skb) {
1165                         if (np->rxopt.bits.rxinfo) {
1166                                 struct in6_pktinfo src_info;
1167                                 src_info.ipi6_ifindex = np->mcast_oif ? np->mcast_oif :
1168                                         np->sticky_pktinfo.ipi6_ifindex;
1169                                 src_info.ipi6_addr = np->mcast_oif ? sk->sk_v6_daddr : np->sticky_pktinfo.ipi6_addr;
1170                                 put_cmsg(&msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info);
1171                         }
1172                         if (np->rxopt.bits.rxhlim) {
1173                                 int hlim = np->mcast_hops;
1174                                 put_cmsg(&msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
1175                         }
1176                         if (np->rxopt.bits.rxtclass) {
1177                                 int tclass = (int)ip6_tclass(np->rcv_flowinfo);
1178
1179                                 put_cmsg(&msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
1180                         }
1181                         if (np->rxopt.bits.rxoinfo) {
1182                                 struct in6_pktinfo src_info;
1183                                 src_info.ipi6_ifindex = np->mcast_oif ? np->mcast_oif :
1184                                         np->sticky_pktinfo.ipi6_ifindex;
1185                                 src_info.ipi6_addr = np->mcast_oif ? sk->sk_v6_daddr :
1186                                                                      np->sticky_pktinfo.ipi6_addr;
1187                                 put_cmsg(&msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
1188                         }
1189                         if (np->rxopt.bits.rxohlim) {
1190                                 int hlim = np->mcast_hops;
1191                                 put_cmsg(&msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
1192                         }
1193                         if (np->rxopt.bits.rxflow) {
1194                                 __be32 flowinfo = np->rcv_flowinfo;
1195
1196                                 put_cmsg(&msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
1197                         }
1198                 }
1199                 len -= msg.msg_controllen;
1200                 return put_user(len, optlen);
1201         }
1202         case IPV6_MTU:
1203         {
1204                 struct dst_entry *dst;
1205
1206                 val = 0;
1207                 rcu_read_lock();
1208                 dst = __sk_dst_get(sk);
1209                 if (dst)
1210                         val = dst_mtu(dst);
1211                 rcu_read_unlock();
1212                 if (!val)
1213                         return -ENOTCONN;
1214                 break;
1215         }
1216
1217         case IPV6_V6ONLY:
1218                 val = sk->sk_ipv6only;
1219                 break;
1220
1221         case IPV6_RECVPKTINFO:
1222                 val = np->rxopt.bits.rxinfo;
1223                 break;
1224
1225         case IPV6_2292PKTINFO:
1226                 val = np->rxopt.bits.rxoinfo;
1227                 break;
1228
1229         case IPV6_RECVHOPLIMIT:
1230                 val = np->rxopt.bits.rxhlim;
1231                 break;
1232
1233         case IPV6_2292HOPLIMIT:
1234                 val = np->rxopt.bits.rxohlim;
1235                 break;
1236
1237         case IPV6_RECVRTHDR:
1238                 val = np->rxopt.bits.srcrt;
1239                 break;
1240
1241         case IPV6_2292RTHDR:
1242                 val = np->rxopt.bits.osrcrt;
1243                 break;
1244
1245         case IPV6_HOPOPTS:
1246         case IPV6_RTHDRDSTOPTS:
1247         case IPV6_RTHDR:
1248         case IPV6_DSTOPTS:
1249         {
1250                 struct ipv6_txoptions *opt;
1251
1252                 lock_sock(sk);
1253                 opt = rcu_dereference_protected(np->opt,
1254                                                 lockdep_sock_is_held(sk));
1255                 len = ipv6_getsockopt_sticky(sk, opt, optname, optval, len);
1256                 release_sock(sk);
1257                 /* check if ipv6_getsockopt_sticky() returns err code */
1258                 if (len < 0)
1259                         return len;
1260                 return put_user(len, optlen);
1261         }
1262
1263         case IPV6_RECVHOPOPTS:
1264                 val = np->rxopt.bits.hopopts;
1265                 break;
1266
1267         case IPV6_2292HOPOPTS:
1268                 val = np->rxopt.bits.ohopopts;
1269                 break;
1270
1271         case IPV6_RECVDSTOPTS:
1272                 val = np->rxopt.bits.dstopts;
1273                 break;
1274
1275         case IPV6_2292DSTOPTS:
1276                 val = np->rxopt.bits.odstopts;
1277                 break;
1278
1279         case IPV6_TCLASS:
1280                 val = np->tclass;
1281                 break;
1282
1283         case IPV6_RECVTCLASS:
1284                 val = np->rxopt.bits.rxtclass;
1285                 break;
1286
1287         case IPV6_FLOWINFO:
1288                 val = np->rxopt.bits.rxflow;
1289                 break;
1290
1291         case IPV6_RECVPATHMTU:
1292                 val = np->rxopt.bits.rxpmtu;
1293                 break;
1294
1295         case IPV6_PATHMTU:
1296         {
1297                 struct dst_entry *dst;
1298                 struct ip6_mtuinfo mtuinfo;
1299
1300                 if (len < sizeof(mtuinfo))
1301                         return -EINVAL;
1302
1303                 len = sizeof(mtuinfo);
1304                 memset(&mtuinfo, 0, sizeof(mtuinfo));
1305
1306                 rcu_read_lock();
1307                 dst = __sk_dst_get(sk);
1308                 if (dst)
1309                         mtuinfo.ip6m_mtu = dst_mtu(dst);
1310                 rcu_read_unlock();
1311                 if (!mtuinfo.ip6m_mtu)
1312                         return -ENOTCONN;
1313
1314                 if (put_user(len, optlen))
1315                         return -EFAULT;
1316                 if (copy_to_user(optval, &mtuinfo, len))
1317                         return -EFAULT;
1318
1319                 return 0;
1320         }
1321
1322         case IPV6_TRANSPARENT:
1323                 val = inet_sk(sk)->transparent;
1324                 break;
1325
1326         case IPV6_FREEBIND:
1327                 val = inet_sk(sk)->freebind;
1328                 break;
1329
1330         case IPV6_RECVORIGDSTADDR:
1331                 val = np->rxopt.bits.rxorigdstaddr;
1332                 break;
1333
1334         case IPV6_UNICAST_HOPS:
1335         case IPV6_MULTICAST_HOPS:
1336         {
1337                 struct dst_entry *dst;
1338
1339                 if (optname == IPV6_UNICAST_HOPS)
1340                         val = np->hop_limit;
1341                 else
1342                         val = np->mcast_hops;
1343
1344                 if (val < 0) {
1345                         rcu_read_lock();
1346                         dst = __sk_dst_get(sk);
1347                         if (dst)
1348                                 val = ip6_dst_hoplimit(dst);
1349                         rcu_read_unlock();
1350                 }
1351
1352                 if (val < 0)
1353                         val = sock_net(sk)->ipv6.devconf_all->hop_limit;
1354                 break;
1355         }
1356
1357         case IPV6_MULTICAST_LOOP:
1358                 val = np->mc_loop;
1359                 break;
1360
1361         case IPV6_MULTICAST_IF:
1362                 val = np->mcast_oif;
1363                 break;
1364
1365         case IPV6_MULTICAST_ALL:
1366                 val = np->mc_all;
1367                 break;
1368
1369         case IPV6_UNICAST_IF:
1370                 val = (__force int)htonl((__u32) np->ucast_oif);
1371                 break;
1372
1373         case IPV6_MTU_DISCOVER:
1374                 val = np->pmtudisc;
1375                 break;
1376
1377         case IPV6_RECVERR:
1378                 val = np->recverr;
1379                 break;
1380
1381         case IPV6_FLOWINFO_SEND:
1382                 val = np->sndflow;
1383                 break;
1384
1385         case IPV6_FLOWLABEL_MGR:
1386         {
1387                 struct in6_flowlabel_req freq;
1388                 int flags;
1389
1390                 if (len < sizeof(freq))
1391                         return -EINVAL;
1392
1393                 if (copy_from_user(&freq, optval, sizeof(freq)))
1394                         return -EFAULT;
1395
1396                 if (freq.flr_action != IPV6_FL_A_GET)
1397                         return -EINVAL;
1398
1399                 len = sizeof(freq);
1400                 flags = freq.flr_flags;
1401
1402                 memset(&freq, 0, sizeof(freq));
1403
1404                 val = ipv6_flowlabel_opt_get(sk, &freq, flags);
1405                 if (val < 0)
1406                         return val;
1407
1408                 if (put_user(len, optlen))
1409                         return -EFAULT;
1410                 if (copy_to_user(optval, &freq, len))
1411                         return -EFAULT;
1412
1413                 return 0;
1414         }
1415
1416         case IPV6_ADDR_PREFERENCES:
1417                 val = 0;
1418
1419                 if (np->srcprefs & IPV6_PREFER_SRC_TMP)
1420                         val |= IPV6_PREFER_SRC_TMP;
1421                 else if (np->srcprefs & IPV6_PREFER_SRC_PUBLIC)
1422                         val |= IPV6_PREFER_SRC_PUBLIC;
1423                 else {
1424                         /* XXX: should we return system default? */
1425                         val |= IPV6_PREFER_SRC_PUBTMP_DEFAULT;
1426                 }
1427
1428                 if (np->srcprefs & IPV6_PREFER_SRC_COA)
1429                         val |= IPV6_PREFER_SRC_COA;
1430                 else
1431                         val |= IPV6_PREFER_SRC_HOME;
1432                 break;
1433
1434         case IPV6_MINHOPCOUNT:
1435                 val = np->min_hopcount;
1436                 break;
1437
1438         case IPV6_DONTFRAG:
1439                 val = np->dontfrag;
1440                 break;
1441
1442         case IPV6_AUTOFLOWLABEL:
1443                 val = ip6_autoflowlabel(sock_net(sk), np);
1444                 break;
1445
1446         case IPV6_RECVFRAGSIZE:
1447                 val = np->rxopt.bits.recvfragsize;
1448                 break;
1449
1450         case IPV6_ROUTER_ALERT_ISOLATE:
1451                 val = np->rtalert_isolate;
1452                 break;
1453
1454         case IPV6_RECVERR_RFC4884:
1455                 val = np->recverr_rfc4884;
1456                 break;
1457
1458         default:
1459                 return -ENOPROTOOPT;
1460         }
1461         len = min_t(unsigned int, sizeof(int), len);
1462         if (put_user(len, optlen))
1463                 return -EFAULT;
1464         if (copy_to_user(optval, &val, len))
1465                 return -EFAULT;
1466         return 0;
1467 }
1468
1469 int ipv6_getsockopt(struct sock *sk, int level, int optname,
1470                     char __user *optval, int __user *optlen)
1471 {
1472         int err;
1473
1474         if (level == SOL_IP && sk->sk_type != SOCK_RAW)
1475                 return udp_prot.getsockopt(sk, level, optname, optval, optlen);
1476
1477         if (level != SOL_IPV6)
1478                 return -ENOPROTOOPT;
1479
1480         err = do_ipv6_getsockopt(sk, level, optname, optval, optlen, 0);
1481 #ifdef CONFIG_NETFILTER
1482         /* we need to exclude all possible ENOPROTOOPTs except default case */
1483         if (err == -ENOPROTOOPT && optname != IPV6_2292PKTOPTIONS) {
1484                 int len;
1485
1486                 if (get_user(len, optlen))
1487                         return -EFAULT;
1488
1489                 err = nf_getsockopt(sk, PF_INET6, optname, optval, &len);
1490                 if (err >= 0)
1491                         err = put_user(len, optlen);
1492         }
1493 #endif
1494         return err;
1495 }
1496 EXPORT_SYMBOL(ipv6_getsockopt);