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                         struct ipv6_txoptions *opt;
 433                         struct sk_buff *pktopt;
 434
 435                         if (sk->sk_type == SOCK_RAW)
 436                                 break;
 437
 438                         if (sk->sk_protocol == IPPROTO_UDP ||
 439                             sk->sk_protocol == IPPROTO_UDPLITE) {
 440                                 struct udp_sock *up = udp_sk(sk);
 441                                 if (up->pending == AF_INET6) {
 442                                         retv = -EBUSY;
 443                                         break;
 444                                 }
 445                         } else if (sk->sk_protocol == IPPROTO_TCP) {
 446                                 if (sk->sk_prot != &tcpv6_prot) {
 447                                         retv = -EBUSY;
 448                                         break;
 449                                 }
 450                         } else {
 451                                 break;
 452                         }
 453
 454                         if (sk->sk_state != TCP_ESTABLISHED) {
 455                                 retv = -ENOTCONN;
 456                                 break;
 457                         }
 458
 459                         if (ipv6_only_sock(sk) ||
 460                             !ipv6_addr_v4mapped(&sk->sk_v6_daddr)) {
 461                                 retv = -EADDRNOTAVAIL;
 462                                 break;
 463                         }
 464
 465                         fl6_free_socklist(sk);
 466                         __ipv6_sock_mc_close(sk);
 467                         __ipv6_sock_ac_close(sk);
 468
 469                         /*
 470                          * Sock is moving from IPv6 to IPv4 (sk_prot), so
 471                          * remove it from the refcnt debug socks count in the
 472                          * original family...
 473                          */
 474                         sk_refcnt_debug_dec(sk);
 475
 476                         if (sk->sk_protocol == IPPROTO_TCP) {
 477                                 struct inet_connection_sock *icsk = inet_csk(sk);
 478                                 local_bh_disable();
 479                                 sock_prot_inuse_add(net, sk->sk_prot, -1);
 480                                 sock_prot_inuse_add(net, &tcp_prot, 1);
 481                                 local_bh_enable();
 482                                 sk->sk_prot = &tcp_prot;
 483                                 icsk->icsk_af_ops = &ipv4_specific;
 484                                 sk->sk_socket->ops = &inet_stream_ops;
 485                                 sk->sk_family = PF_INET;
 486                                 tcp_sync_mss(sk, icsk->icsk_pmtu_cookie);
 487                         } else {
 488                                 struct proto *prot = &udp_prot;
 489
 490                                 if (sk->sk_protocol == IPPROTO_UDPLITE)
 491                                         prot = &udplite_prot;
 492                                 local_bh_disable();
 493                                 sock_prot_inuse_add(net, sk->sk_prot, -1);
 494                                 sock_prot_inuse_add(net, prot, 1);
 495                                 local_bh_enable();
 496                                 sk->sk_prot = prot;
 497                                 sk->sk_socket->ops = &inet_dgram_ops;
 498                                 sk->sk_family = PF_INET;
 499                         }
 500                         opt = xchg((__force struct ipv6_txoptions **)&np->opt,
 501                                    NULL);
 502                         if (opt) {
 503                                 atomic_sub(opt->tot_len, &sk->sk_omem_alloc);
 504                                 txopt_put(opt);
 505                         }
 506                         pktopt = xchg(&np->pktoptions, NULL);
 507                         kfree_skb(pktopt);
 508
 509                         /*
 510                          * ... and add it to the refcnt debug socks count
 511                          * in the new family. -acme
 512                          */
 513                         sk_refcnt_debug_inc(sk);
 514                         module_put(THIS_MODULE);
 515                         retv = 0;
 516                         break;
 517                 }
 518                 goto e_inval;
 519
 520         case IPV6_V6ONLY:
 521                 if (optlen < sizeof(int) ||
 522                     inet_sk(sk)->inet_num)
 523                         goto e_inval;
 524                 sk->sk_ipv6only = valbool;
 525                 retv = 0;
 526                 break;
 527
 528         case IPV6_RECVPKTINFO:
 529                 if (optlen < sizeof(int))
 530                         goto e_inval;
 531                 np->rxopt.bits.rxinfo = valbool;
 532                 retv = 0;
 533                 break;
 534
 535         case IPV6_2292PKTINFO:
 536                 if (optlen < sizeof(int))
 537                         goto e_inval;
 538                 np->rxopt.bits.rxoinfo = valbool;
 539                 retv = 0;
 540                 break;
 541
 542         case IPV6_RECVHOPLIMIT:
 543                 if (optlen < sizeof(int))
 544                         goto e_inval;
 545                 np->rxopt.bits.rxhlim = valbool;
 546                 retv = 0;
 547                 break;
 548
 549         case IPV6_2292HOPLIMIT:
 550                 if (optlen < sizeof(int))
 551                         goto e_inval;
 552                 np->rxopt.bits.rxohlim = valbool;
 553                 retv = 0;
 554                 break;
 555
 556         case IPV6_RECVRTHDR:
 557                 if (optlen < sizeof(int))
 558                         goto e_inval;
 559                 np->rxopt.bits.srcrt = valbool;
 560                 retv = 0;
 561                 break;
 562
 563         case IPV6_2292RTHDR:
 564                 if (optlen < sizeof(int))
 565                         goto e_inval;
 566                 np->rxopt.bits.osrcrt = valbool;
 567                 retv = 0;
 568                 break;
 569
 570         case IPV6_RECVHOPOPTS:
 571                 if (optlen < sizeof(int))
 572                         goto e_inval;
 573                 np->rxopt.bits.hopopts = valbool;
 574                 retv = 0;
 575                 break;
 576
 577         case IPV6_2292HOPOPTS:
 578                 if (optlen < sizeof(int))
 579                         goto e_inval;
 580                 np->rxopt.bits.ohopopts = valbool;
 581                 retv = 0;
 582                 break;
 583
 584         case IPV6_RECVDSTOPTS:
 585                 if (optlen < sizeof(int))
 586                         goto e_inval;
 587                 np->rxopt.bits.dstopts = valbool;
 588                 retv = 0;
 589                 break;
 590
 591         case IPV6_2292DSTOPTS:
 592                 if (optlen < sizeof(int))
 593                         goto e_inval;
 594                 np->rxopt.bits.odstopts = valbool;
 595                 retv = 0;
 596                 break;
 597
 598         case IPV6_TCLASS:
 599                 if (optlen < sizeof(int))
 600                         goto e_inval;
 601                 if (val < -1 || val > 0xff)
 602                         goto e_inval;
 603                 /* RFC 3542, 6.5: default traffic class of 0x0 */
 604                 if (val == -1)
 605                         val = 0;
 606                 np->tclass = val;
 607                 retv = 0;
 608                 break;
 609
 610         case IPV6_RECVTCLASS:
 611                 if (optlen < sizeof(int))
 612                         goto e_inval;
 613                 np->rxopt.bits.rxtclass = valbool;
 614                 retv = 0;
 615                 break;
 616
 617         case IPV6_FLOWINFO:
 618                 if (optlen < sizeof(int))
 619                         goto e_inval;
 620                 np->rxopt.bits.rxflow = valbool;
 621                 retv = 0;
 622                 break;
 623
 624         case IPV6_RECVPATHMTU:
 625                 if (optlen < sizeof(int))
 626                         goto e_inval;
 627                 np->rxopt.bits.rxpmtu = valbool;
 628                 retv = 0;
 629                 break;
 630
 631         case IPV6_TRANSPARENT:
 632                 if (valbool && !ns_capable(net->user_ns, CAP_NET_RAW) &&
 633                     !ns_capable(net->user_ns, CAP_NET_ADMIN)) {
 634                         retv = -EPERM;
 635                         break;
 636                 }
 637                 if (optlen < sizeof(int))
 638                         goto e_inval;
 639                 /* we don't have a separate transparent bit for IPV6 we use the one in the IPv4 socket */
 640                 inet_sk(sk)->transparent = valbool;
 641                 retv = 0;
 642                 break;
 643
 644         case IPV6_FREEBIND:
 645                 if (optlen < sizeof(int))
 646                         goto e_inval;
 647                 /* we also don't have a separate freebind bit for IPV6 */
 648                 inet_sk(sk)->freebind = valbool;
 649                 retv = 0;
 650                 break;
 651
 652         case IPV6_RECVORIGDSTADDR:
 653                 if (optlen < sizeof(int))
 654                         goto e_inval;
 655                 np->rxopt.bits.rxorigdstaddr = valbool;
 656                 retv = 0;
 657                 break;
 658
 659         case IPV6_HOPOPTS:
 660         case IPV6_RTHDRDSTOPTS:
 661         case IPV6_RTHDR:
 662         case IPV6_DSTOPTS:
 663                 retv = ipv6_set_opt_hdr(sk, optname, optval, optlen);
 664                 break;
 665
 666         case IPV6_PKTINFO:
 667         {
 668                 struct in6_pktinfo pkt;
 669
 670                 if (optlen == 0)
 671                         goto e_inval;
 672                 else if (optlen < sizeof(struct in6_pktinfo) ||
 673                          sockptr_is_null(optval))
 674                         goto e_inval;
 675
 676                 if (copy_from_sockptr(&pkt, optval, sizeof(pkt))) {
 677                         retv = -EFAULT;
 678                         break;
 679                 }
 680                 if (!sk_dev_equal_l3scope(sk, pkt.ipi6_ifindex))
 681                         goto e_inval;
 682
 683                 np->sticky_pktinfo.ipi6_ifindex = pkt.ipi6_ifindex;
 684                 np->sticky_pktinfo.ipi6_addr = pkt.ipi6_addr;
 685                 retv = 0;
 686                 break;
 687         }
 688
 689         case IPV6_2292PKTOPTIONS:
 690         {
 691                 struct ipv6_txoptions *opt = NULL;
 692                 struct msghdr msg;
 693                 struct flowi6 fl6;
 694                 struct ipcm6_cookie ipc6;
 695
 696                 memset(&fl6, 0, sizeof(fl6));
 697                 fl6.flowi6_oif = sk->sk_bound_dev_if;
 698                 fl6.flowi6_mark = sk->sk_mark;
 699
 700                 if (optlen == 0)
 701                         goto update;
 702
 703                 /* 1K is probably excessive
 704                  * 1K is surely not enough, 2K per standard header is 16K.
 705                  */
 706                 retv = -EINVAL;
 707                 if (optlen > 64*1024)
 708                         break;
 709
 710                 opt = sock_kmalloc(sk, sizeof(*opt) + optlen, GFP_KERNEL);
 711                 retv = -ENOBUFS;
 712                 if (!opt)
 713                         break;
 714
 715                 memset(opt, 0, sizeof(*opt));
 716                 refcount_set(&opt->refcnt, 1);
 717                 opt->tot_len = sizeof(*opt) + optlen;
 718                 retv = -EFAULT;
 719                 if (copy_from_sockptr(opt + 1, optval, optlen))
 720                         goto done;
 721
 722                 msg.msg_controllen = optlen;
 723                 msg.msg_control = (void *)(opt+1);
 724                 ipc6.opt = opt;
 725
 726                 retv = ip6_datagram_send_ctl(net, sk, &msg, &fl6, &ipc6);
 727                 if (retv)
 728                         goto done;
 729 update:
 730                 retv = 0;
 731                 opt = ipv6_update_options(sk, opt);
 732 done:
 733                 if (opt) {
 734                         atomic_sub(opt->tot_len, &sk->sk_omem_alloc);
 735                         txopt_put(opt);
 736                 }
 737                 break;
 738         }
 739         case IPV6_UNICAST_HOPS:
 740                 if (optlen < sizeof(int))
 741                         goto e_inval;
 742                 if (val > 255 || val < -1)
 743                         goto e_inval;
 744                 np->hop_limit = val;
 745                 retv = 0;
 746                 break;
 747
 748         case IPV6_MULTICAST_HOPS:
 749                 if (sk->sk_type == SOCK_STREAM)
 750                         break;
 751                 if (optlen < sizeof(int))
 752                         goto e_inval;
 753                 if (val > 255 || val < -1)
 754                         goto e_inval;
 755                 np->mcast_hops = (val == -1 ? IPV6_DEFAULT_MCASTHOPS : val);
 756                 retv = 0;
 757                 break;
 758
 759         case IPV6_MULTICAST_LOOP:
 760                 if (optlen < sizeof(int))
 761                         goto e_inval;
 762                 if (val != valbool)
 763                         goto e_inval;
 764                 np->mc_loop = valbool;
 765                 retv = 0;
 766                 break;
 767
 768         case IPV6_UNICAST_IF:
 769         {
 770                 struct net_device *dev = NULL;
 771                 int ifindex;
 772
 773                 if (optlen != sizeof(int))
 774                         goto e_inval;
 775
 776                 ifindex = (__force int)ntohl((__force __be32)val);
 777                 if (ifindex == 0) {
 778                         np->ucast_oif = 0;
 779                         retv = 0;
 780                         break;
 781                 }
 782
 783                 dev = dev_get_by_index(net, ifindex);
 784                 retv = -EADDRNOTAVAIL;
 785                 if (!dev)
 786                         break;
 787                 dev_put(dev);
 788
 789                 retv = -EINVAL;
 790                 if (sk->sk_bound_dev_if)
 791                         break;
 792
 793                 np->ucast_oif = ifindex;
 794                 retv = 0;
 795                 break;
 796         }
 797
 798         case IPV6_MULTICAST_IF:
 799                 if (sk->sk_type == SOCK_STREAM)
 800                         break;
 801                 if (optlen < sizeof(int))
 802                         goto e_inval;
 803
 804                 if (val) {
 805                         struct net_device *dev;
 806                         int midx;
 807
 808                         rcu_read_lock();
 809
 810                         dev = dev_get_by_index_rcu(net, val);
 811                         if (!dev) {
 812                                 rcu_read_unlock();
 813                                 retv = -ENODEV;
 814                                 break;
 815                         }
 816                         midx = l3mdev_master_ifindex_rcu(dev);
 817
 818                         rcu_read_unlock();
 819
 820                         if (sk->sk_bound_dev_if &&
 821                             sk->sk_bound_dev_if != val &&
 822                             (!midx || midx != sk->sk_bound_dev_if))
 823                                 goto e_inval;
 824                 }
 825                 np->mcast_oif = val;
 826                 retv = 0;
 827                 break;
 828         case IPV6_ADD_MEMBERSHIP:
 829         case IPV6_DROP_MEMBERSHIP:
 830         {
 831                 struct ipv6_mreq mreq;
 832
 833                 if (optlen < sizeof(struct ipv6_mreq))
 834                         goto e_inval;
 835
 836                 retv = -EPROTO;
 837                 if (inet_sk(sk)->is_icsk)
 838                         break;
 839
 840                 retv = -EFAULT;
 841                 if (copy_from_sockptr(&mreq, optval, sizeof(struct ipv6_mreq)))
 842                         break;
 843
 844                 if (optname == IPV6_ADD_MEMBERSHIP)
 845                         retv = ipv6_sock_mc_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr);
 846                 else
 847                         retv = ipv6_sock_mc_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr);
 848                 break;
 849         }
 850         case IPV6_JOIN_ANYCAST:
 851         case IPV6_LEAVE_ANYCAST:
 852         {
 853                 struct ipv6_mreq mreq;
 854
 855                 if (optlen < sizeof(struct ipv6_mreq))
 856                         goto e_inval;
 857
 858                 retv = -EFAULT;
 859                 if (copy_from_sockptr(&mreq, optval, sizeof(struct ipv6_mreq)))
 860                         break;
 861
 862                 if (optname == IPV6_JOIN_ANYCAST)
 863                         retv = ipv6_sock_ac_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_acaddr);
 864                 else
 865                         retv = ipv6_sock_ac_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_acaddr);
 866                 break;
 867         }
 868         case IPV6_MULTICAST_ALL:
 869                 if (optlen < sizeof(int))
 870                         goto e_inval;
 871                 np->mc_all = valbool;
 872                 retv = 0;
 873                 break;
 874
 875         case MCAST_JOIN_GROUP:
 876         case MCAST_LEAVE_GROUP:
 877                 if (in_compat_syscall())
 878                         retv = compat_ipv6_mcast_join_leave(sk, optname, optval,
 879                                                             optlen);
 880                 else
 881                         retv = ipv6_mcast_join_leave(sk, optname, optval,
 882                                                      optlen);
 883                 break;
 884         case MCAST_JOIN_SOURCE_GROUP:
 885         case MCAST_LEAVE_SOURCE_GROUP:
 886         case MCAST_BLOCK_SOURCE:
 887         case MCAST_UNBLOCK_SOURCE:
 888                 retv = do_ipv6_mcast_group_source(sk, optname, optval, optlen);
 889                 break;
 890         case MCAST_MSFILTER:
 891                 if (in_compat_syscall())
 892                         retv = compat_ipv6_set_mcast_msfilter(sk, optval,
 893                                                               optlen);
 894                 else
 895                         retv = ipv6_set_mcast_msfilter(sk, optval, optlen);
 896                 break;
 897         case IPV6_ROUTER_ALERT:
 898                 if (optlen < sizeof(int))
 899                         goto e_inval;
 900                 retv = ip6_ra_control(sk, val);
 901                 break;
 902         case IPV6_ROUTER_ALERT_ISOLATE:
 903                 if (optlen < sizeof(int))
 904                         goto e_inval;
 905                 np->rtalert_isolate = valbool;
 906                 retv = 0;
 907                 break;
 908         case IPV6_MTU_DISCOVER:
 909                 if (optlen < sizeof(int))
 910                         goto e_inval;
 911                 if (val < IPV6_PMTUDISC_DONT || val > IPV6_PMTUDISC_OMIT)
 912                         goto e_inval;
 913                 np->pmtudisc = val;
 914                 retv = 0;
 915                 break;
 916         case IPV6_MTU:
 917                 if (optlen < sizeof(int))
 918                         goto e_inval;
 919                 if (val && val < IPV6_MIN_MTU)
 920                         goto e_inval;
 921                 np->frag_size = val;
 922                 retv = 0;
 923                 break;
 924         case IPV6_RECVERR:
 925                 if (optlen < sizeof(int))
 926                         goto e_inval;
 927                 np->recverr = valbool;
 928                 if (!val)
 929                         skb_queue_purge(&sk->sk_error_queue);
 930                 retv = 0;
 931                 break;
 932         case IPV6_FLOWINFO_SEND:
 933                 if (optlen < sizeof(int))
 934                         goto e_inval;
 935                 np->sndflow = valbool;
 936                 retv = 0;
 937                 break;
 938         case IPV6_FLOWLABEL_MGR:
 939                 retv = ipv6_flowlabel_opt(sk, optval, optlen);
 940                 break;
 941         case IPV6_IPSEC_POLICY:
 942         case IPV6_XFRM_POLICY:
 943                 retv = -EPERM;
 944                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 945                         break;
 946                 retv = xfrm_user_policy(sk, optname, optval, optlen);
 947                 break;
 948
 949         case IPV6_ADDR_PREFERENCES:
 950                 if (optlen < sizeof(int))
 951                         goto e_inval;
 952                 retv = __ip6_sock_set_addr_preferences(sk, val);
 953                 break;
 954         case IPV6_MINHOPCOUNT:
 955                 if (optlen < sizeof(int))
 956                         goto e_inval;
 957                 if (val < 0 || val > 255)
 958                         goto e_inval;
 959                 np->min_hopcount = val;
 960                 retv = 0;
 961                 break;
 962         case IPV6_DONTFRAG:
 963                 np->dontfrag = valbool;
 964                 retv = 0;
 965                 break;
 966         case IPV6_AUTOFLOWLABEL:
 967                 np->autoflowlabel = valbool;
 968                 np->autoflowlabel_set = 1;
 969                 retv = 0;
 970                 break;
 971         case IPV6_RECVFRAGSIZE:
 972                 np->rxopt.bits.recvfragsize = valbool;
 973                 retv = 0;
 974                 break;
 975         case IPV6_RECVERR_RFC4884:
 976                 if (optlen < sizeof(int))
 977                         goto e_inval;
 978                 if (val < 0 || val > 1)
 979                         goto e_inval;
 980                 np->recverr_rfc4884 = valbool;
 981                 retv = 0;
 982                 break;
 983         }
 984
 985 unlock:
 986         release_sock(sk);
 987         if (needs_rtnl)
 988                 rtnl_unlock();
 989
 990         return retv;
 991
 992 e_inval:
 993         release_sock(sk);
 994         if (needs_rtnl)
 995                 rtnl_unlock();
 996         return -EINVAL;
 997 }
 998
 999 int ipv6_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
1000                     unsigned int optlen)
1001 {
1002         int err;
1003
1004         if (level == SOL_IP && sk->sk_type != SOCK_RAW)
1005                 return udp_prot.setsockopt(sk, level, optname, optval, optlen);
1006
1007         if (level != SOL_IPV6)
1008                 return -ENOPROTOOPT;
1009
1010         err = do_ipv6_setsockopt(sk, level, optname, optval, optlen);
1011 #ifdef CONFIG_NETFILTER
1012         /* we need to exclude all possible ENOPROTOOPTs except default case */
1013         if (err == -ENOPROTOOPT && optname != IPV6_IPSEC_POLICY &&
1014                         optname != IPV6_XFRM_POLICY)
1015                 err = nf_setsockopt(sk, PF_INET6, optname, optval, optlen);
1016 #endif
1017         return err;
1018 }
1019 EXPORT_SYMBOL(ipv6_setsockopt);
1020
1021 static int ipv6_getsockopt_sticky(struct sock *sk, struct ipv6_txoptions *opt,
1022                                   int optname, char __user *optval, int len)
1023 {
1024         struct ipv6_opt_hdr *hdr;
1025
1026         if (!opt)
1027                 return 0;
1028
1029         switch (optname) {
1030         case IPV6_HOPOPTS:
1031                 hdr = opt->hopopt;
1032                 break;
1033         case IPV6_RTHDRDSTOPTS:
1034                 hdr = opt->dst0opt;
1035                 break;
1036         case IPV6_RTHDR:
1037                 hdr = (struct ipv6_opt_hdr *)opt->srcrt;
1038                 break;
1039         case IPV6_DSTOPTS:
1040                 hdr = opt->dst1opt;
1041                 break;
1042         default:
1043                 return -EINVAL; /* should not happen */
1044         }
1045
1046         if (!hdr)
1047                 return 0;
1048
1049         len = min_t(unsigned int, len, ipv6_optlen(hdr));
1050         if (copy_to_user(optval, hdr, len))
1051                 return -EFAULT;
1052         return len;
1053 }
1054
1055 static int ipv6_get_msfilter(struct sock *sk, void __user *optval,
1056                 int __user *optlen, int len)
1057 {
1058         const int size0 = offsetof(struct group_filter, gf_slist_flex);
1059         struct group_filter __user *p = optval;
1060         struct group_filter gsf;
1061         int num;
1062         int err;
1063
1064         if (len < size0)
1065                 return -EINVAL;
1066         if (copy_from_user(&gsf, p, size0))
1067                 return -EFAULT;
1068         if (gsf.gf_group.ss_family != AF_INET6)
1069                 return -EADDRNOTAVAIL;
1070         num = gsf.gf_numsrc;
1071         lock_sock(sk);
1072         err = ip6_mc_msfget(sk, &gsf, p->gf_slist_flex);
1073         if (!err) {
1074                 if (num > gsf.gf_numsrc)
1075                         num = gsf.gf_numsrc;
1076                 if (put_user(GROUP_FILTER_SIZE(num), optlen) ||
1077                     copy_to_user(p, &gsf, size0))
1078                         err = -EFAULT;
1079         }
1080         release_sock(sk);
1081         return err;
1082 }
1083
1084 static int compat_ipv6_get_msfilter(struct sock *sk, void __user *optval,
1085                 int __user *optlen)
1086 {
1087         const int size0 = offsetof(struct compat_group_filter, gf_slist_flex);
1088         struct compat_group_filter __user *p = optval;
1089         struct compat_group_filter gf32;
1090         struct group_filter gf;
1091         int len, err;
1092         int num;
1093
1094         if (get_user(len, optlen))
1095                 return -EFAULT;
1096         if (len < size0)
1097                 return -EINVAL;
1098
1099         if (copy_from_user(&gf32, p, size0))
1100                 return -EFAULT;
1101         gf.gf_interface = gf32.gf_interface;
1102         gf.gf_fmode = gf32.gf_fmode;
1103         num = gf.gf_numsrc = gf32.gf_numsrc;
1104         gf.gf_group = gf32.gf_group;
1105
1106         if (gf.gf_group.ss_family != AF_INET6)
1107                 return -EADDRNOTAVAIL;
1108
1109         lock_sock(sk);
1110         err = ip6_mc_msfget(sk, &gf, p->gf_slist_flex);
1111         release_sock(sk);
1112         if (err)
1113                 return err;
1114         if (num > gf.gf_numsrc)
1115                 num = gf.gf_numsrc;
1116         len = GROUP_FILTER_SIZE(num) - (sizeof(gf)-sizeof(gf32));
1117         if (put_user(len, optlen) ||
1118             put_user(gf.gf_fmode, &p->gf_fmode) ||
1119             put_user(gf.gf_numsrc, &p->gf_numsrc))
1120                 return -EFAULT;
1121         return 0;
1122 }
1123
1124 static int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
1125                     char __user *optval, int __user *optlen, unsigned int flags)
1126 {
1127         struct ipv6_pinfo *np = inet6_sk(sk);
1128         int len;
1129         int val;
1130
1131         if (ip6_mroute_opt(optname))
1132                 return ip6_mroute_getsockopt(sk, optname, optval, optlen);
1133
1134         if (get_user(len, optlen))
1135                 return -EFAULT;
1136         switch (optname) {
1137         case IPV6_ADDRFORM:
1138                 if (sk->sk_protocol != IPPROTO_UDP &&
1139                     sk->sk_protocol != IPPROTO_UDPLITE &&
1140                     sk->sk_protocol != IPPROTO_TCP)
1141                         return -ENOPROTOOPT;
1142                 if (sk->sk_state != TCP_ESTABLISHED)
1143                         return -ENOTCONN;
1144                 val = sk->sk_family;
1145                 break;
1146         case MCAST_MSFILTER:
1147                 if (in_compat_syscall())
1148                         return compat_ipv6_get_msfilter(sk, optval, optlen);
1149                 return ipv6_get_msfilter(sk, optval, optlen, len);
1150         case IPV6_2292PKTOPTIONS:
1151         {
1152                 struct msghdr msg;
1153                 struct sk_buff *skb;
1154
1155                 if (sk->sk_type != SOCK_STREAM)
1156                         return -ENOPROTOOPT;
1157
1158                 msg.msg_control_user = optval;
1159                 msg.msg_controllen = len;
1160                 msg.msg_flags = flags;
1161                 msg.msg_control_is_user = true;
1162
1163                 lock_sock(sk);
1164                 skb = np->pktoptions;
1165                 if (skb)
1166                         ip6_datagram_recv_ctl(sk, &msg, skb);
1167                 release_sock(sk);
1168                 if (!skb) {
1169                         if (np->rxopt.bits.rxinfo) {
1170                                 struct in6_pktinfo src_info;
1171                                 src_info.ipi6_ifindex = np->mcast_oif ? np->mcast_oif :
1172                                         np->sticky_pktinfo.ipi6_ifindex;
1173                                 src_info.ipi6_addr = np->mcast_oif ? sk->sk_v6_daddr : np->sticky_pktinfo.ipi6_addr;
1174                                 put_cmsg(&msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info);
1175                         }
1176                         if (np->rxopt.bits.rxhlim) {
1177                                 int hlim = np->mcast_hops;
1178                                 put_cmsg(&msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
1179                         }
1180                         if (np->rxopt.bits.rxtclass) {
1181                                 int tclass = (int)ip6_tclass(np->rcv_flowinfo);
1182
1183                                 put_cmsg(&msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
1184                         }
1185                         if (np->rxopt.bits.rxoinfo) {
1186                                 struct in6_pktinfo src_info;
1187                                 src_info.ipi6_ifindex = np->mcast_oif ? np->mcast_oif :
1188                                         np->sticky_pktinfo.ipi6_ifindex;
1189                                 src_info.ipi6_addr = np->mcast_oif ? sk->sk_v6_daddr :
1190                                                                      np->sticky_pktinfo.ipi6_addr;
1191                                 put_cmsg(&msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
1192                         }
1193                         if (np->rxopt.bits.rxohlim) {
1194                                 int hlim = np->mcast_hops;
1195                                 put_cmsg(&msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
1196                         }
1197                         if (np->rxopt.bits.rxflow) {
1198                                 __be32 flowinfo = np->rcv_flowinfo;
1199
1200                                 put_cmsg(&msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
1201                         }
1202                 }
1203                 len -= msg.msg_controllen;
1204                 return put_user(len, optlen);
1205         }
1206         case IPV6_MTU:
1207         {
1208                 struct dst_entry *dst;
1209
1210                 val = 0;
1211                 rcu_read_lock();
1212                 dst = __sk_dst_get(sk);
1213                 if (dst)
1214                         val = dst_mtu(dst);
1215                 rcu_read_unlock();
1216                 if (!val)
1217                         return -ENOTCONN;
1218                 break;
1219         }
1220
1221         case IPV6_V6ONLY:
1222                 val = sk->sk_ipv6only;
1223                 break;
1224
1225         case IPV6_RECVPKTINFO:
1226                 val = np->rxopt.bits.rxinfo;
1227                 break;
1228
1229         case IPV6_2292PKTINFO:
1230                 val = np->rxopt.bits.rxoinfo;
1231                 break;
1232
1233         case IPV6_RECVHOPLIMIT:
1234                 val = np->rxopt.bits.rxhlim;
1235                 break;
1236
1237         case IPV6_2292HOPLIMIT:
1238                 val = np->rxopt.bits.rxohlim;
1239                 break;
1240
1241         case IPV6_RECVRTHDR:
1242                 val = np->rxopt.bits.srcrt;
1243                 break;
1244
1245         case IPV6_2292RTHDR:
1246                 val = np->rxopt.bits.osrcrt;
1247                 break;
1248
1249         case IPV6_HOPOPTS:
1250         case IPV6_RTHDRDSTOPTS:
1251         case IPV6_RTHDR:
1252         case IPV6_DSTOPTS:
1253         {
1254                 struct ipv6_txoptions *opt;
1255
1256                 lock_sock(sk);
1257                 opt = rcu_dereference_protected(np->opt,
1258                                                 lockdep_sock_is_held(sk));
1259                 len = ipv6_getsockopt_sticky(sk, opt, optname, optval, len);
1260                 release_sock(sk);
1261                 /* check if ipv6_getsockopt_sticky() returns err code */
1262                 if (len < 0)
1263                         return len;
1264                 return put_user(len, optlen);
1265         }
1266
1267         case IPV6_RECVHOPOPTS:
1268                 val = np->rxopt.bits.hopopts;
1269                 break;
1270
1271         case IPV6_2292HOPOPTS:
1272                 val = np->rxopt.bits.ohopopts;
1273                 break;
1274
1275         case IPV6_RECVDSTOPTS:
1276                 val = np->rxopt.bits.dstopts;
1277                 break;
1278
1279         case IPV6_2292DSTOPTS:
1280                 val = np->rxopt.bits.odstopts;
1281                 break;
1282
1283         case IPV6_TCLASS:
1284                 val = np->tclass;
1285                 break;
1286
1287         case IPV6_RECVTCLASS:
1288                 val = np->rxopt.bits.rxtclass;
1289                 break;
1290
1291         case IPV6_FLOWINFO:
1292                 val = np->rxopt.bits.rxflow;
1293                 break;
1294
1295         case IPV6_RECVPATHMTU:
1296                 val = np->rxopt.bits.rxpmtu;
1297                 break;
1298
1299         case IPV6_PATHMTU:
1300         {
1301                 struct dst_entry *dst;
1302                 struct ip6_mtuinfo mtuinfo;
1303
1304                 if (len < sizeof(mtuinfo))
1305                         return -EINVAL;
1306
1307                 len = sizeof(mtuinfo);
1308                 memset(&mtuinfo, 0, sizeof(mtuinfo));
1309
1310                 rcu_read_lock();
1311                 dst = __sk_dst_get(sk);
1312                 if (dst)
1313                         mtuinfo.ip6m_mtu = dst_mtu(dst);
1314                 rcu_read_unlock();
1315                 if (!mtuinfo.ip6m_mtu)
1316                         return -ENOTCONN;
1317
1318                 if (put_user(len, optlen))
1319                         return -EFAULT;
1320                 if (copy_to_user(optval, &mtuinfo, len))
1321                         return -EFAULT;
1322
1323                 return 0;
1324         }
1325
1326         case IPV6_TRANSPARENT:
1327                 val = inet_sk(sk)->transparent;
1328                 break;
1329
1330         case IPV6_FREEBIND:
1331                 val = inet_sk(sk)->freebind;
1332                 break;
1333
1334         case IPV6_RECVORIGDSTADDR:
1335                 val = np->rxopt.bits.rxorigdstaddr;
1336                 break;
1337
1338         case IPV6_UNICAST_HOPS:
1339         case IPV6_MULTICAST_HOPS:
1340         {
1341                 struct dst_entry *dst;
1342
1343                 if (optname == IPV6_UNICAST_HOPS)
1344                         val = np->hop_limit;
1345                 else
1346                         val = np->mcast_hops;
1347
1348                 if (val < 0) {
1349                         rcu_read_lock();
1350                         dst = __sk_dst_get(sk);
1351                         if (dst)
1352                                 val = ip6_dst_hoplimit(dst);
1353                         rcu_read_unlock();
1354                 }
1355
1356                 if (val < 0)
1357                         val = sock_net(sk)->ipv6.devconf_all->hop_limit;
1358                 break;
1359         }
1360
1361         case IPV6_MULTICAST_LOOP:
1362                 val = np->mc_loop;
1363                 break;
1364
1365         case IPV6_MULTICAST_IF:
1366                 val = np->mcast_oif;
1367                 break;
1368
1369         case IPV6_MULTICAST_ALL:
1370                 val = np->mc_all;
1371                 break;
1372
1373         case IPV6_UNICAST_IF:
1374                 val = (__force int)htonl((__u32) np->ucast_oif);
1375                 break;
1376
1377         case IPV6_MTU_DISCOVER:
1378                 val = np->pmtudisc;
1379                 break;
1380
1381         case IPV6_RECVERR:
1382                 val = np->recverr;
1383                 break;
1384
1385         case IPV6_FLOWINFO_SEND:
1386                 val = np->sndflow;
1387                 break;
1388
1389         case IPV6_FLOWLABEL_MGR:
1390         {
1391                 struct in6_flowlabel_req freq;
1392                 int flags;
1393
1394                 if (len < sizeof(freq))
1395                         return -EINVAL;
1396
1397                 if (copy_from_user(&freq, optval, sizeof(freq)))
1398                         return -EFAULT;
1399
1400                 if (freq.flr_action != IPV6_FL_A_GET)
1401                         return -EINVAL;
1402
1403                 len = sizeof(freq);
1404                 flags = freq.flr_flags;
1405
1406                 memset(&freq, 0, sizeof(freq));
1407
1408                 val = ipv6_flowlabel_opt_get(sk, &freq, flags);
1409                 if (val < 0)
1410                         return val;
1411
1412                 if (put_user(len, optlen))
1413                         return -EFAULT;
1414                 if (copy_to_user(optval, &freq, len))
1415                         return -EFAULT;
1416
1417                 return 0;
1418         }
1419
1420         case IPV6_ADDR_PREFERENCES:
1421                 val = 0;
1422
1423                 if (np->srcprefs & IPV6_PREFER_SRC_TMP)
1424                         val |= IPV6_PREFER_SRC_TMP;
1425                 else if (np->srcprefs & IPV6_PREFER_SRC_PUBLIC)
1426                         val |= IPV6_PREFER_SRC_PUBLIC;
1427                 else {
1428                         /* XXX: should we return system default? */
1429                         val |= IPV6_PREFER_SRC_PUBTMP_DEFAULT;
1430                 }
1431
1432                 if (np->srcprefs & IPV6_PREFER_SRC_COA)
1433                         val |= IPV6_PREFER_SRC_COA;
1434                 else
1435                         val |= IPV6_PREFER_SRC_HOME;
1436                 break;
1437
1438         case IPV6_MINHOPCOUNT:
1439                 val = np->min_hopcount;
1440                 break;
1441
1442         case IPV6_DONTFRAG:
1443                 val = np->dontfrag;
1444                 break;
1445
1446         case IPV6_AUTOFLOWLABEL:
1447                 val = ip6_autoflowlabel(sock_net(sk), np);
1448                 break;
1449
1450         case IPV6_RECVFRAGSIZE:
1451                 val = np->rxopt.bits.recvfragsize;
1452                 break;
1453
1454         case IPV6_ROUTER_ALERT_ISOLATE:
1455                 val = np->rtalert_isolate;
1456                 break;
1457
1458         case IPV6_RECVERR_RFC4884:
1459                 val = np->recverr_rfc4884;
1460                 break;
1461
1462         default:
1463                 return -ENOPROTOOPT;
1464         }
1465         len = min_t(unsigned int, sizeof(int), len);
1466         if (put_user(len, optlen))
1467                 return -EFAULT;
1468         if (copy_to_user(optval, &val, len))
1469                 return -EFAULT;
1470         return 0;
1471 }
1472
1473 int ipv6_getsockopt(struct sock *sk, int level, int optname,
1474                     char __user *optval, int __user *optlen)
1475 {
1476         int err;
1477
1478         if (level == SOL_IP && sk->sk_type != SOCK_RAW)
1479                 return udp_prot.getsockopt(sk, level, optname, optval, optlen);
1480
1481         if (level != SOL_IPV6)
1482                 return -ENOPROTOOPT;
1483
1484         err = do_ipv6_getsockopt(sk, level, optname, optval, optlen, 0);
1485 #ifdef CONFIG_NETFILTER
1486         /* we need to exclude all possible ENOPROTOOPTs except default case */
1487         if (err == -ENOPROTOOPT && optname != IPV6_2292PKTOPTIONS) {
1488                 int len;
1489
1490                 if (get_user(len, optlen))
1491                         return -EFAULT;
1492
1493                 err = nf_getsockopt(sk, PF_INET6, optname, optval, &len);
1494                 if (err >= 0)
1495                         err = put_user(len, optlen);
1496         }
1497 #endif
1498         return err;
1499 }
1500 EXPORT_SYMBOL(ipv6_getsockopt);