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 DEFINE_STATIC_KEY_FALSE(ip6_min_hopcount);
  59
  60 int ip6_ra_control(struct sock *sk, int sel)
  61 {
  62         struct ip6_ra_chain *ra, *new_ra, **rap;
  63
  64         /* RA packet may be delivered ONLY to IPPROTO_RAW socket */
  65         if (sk->sk_type != SOCK_RAW || inet_sk(sk)->inet_num != IPPROTO_RAW)
  66                 return -ENOPROTOOPT;
  67
  68         new_ra = (sel >= 0) ? kmalloc(sizeof(*new_ra), GFP_KERNEL) : NULL;
  69         if (sel >= 0 && !new_ra)
  70                 return -ENOMEM;
  71
  72         write_lock_bh(&ip6_ra_lock);
  73         for (rap = &ip6_ra_chain; (ra = *rap) != NULL; rap = &ra->next) {
  74                 if (ra->sk == sk) {
  75                         if (sel >= 0) {
  76                                 write_unlock_bh(&ip6_ra_lock);
  77                                 kfree(new_ra);
  78                                 return -EADDRINUSE;
  79                         }
  80
  81                         *rap = ra->next;
  82                         write_unlock_bh(&ip6_ra_lock);
  83
  84                         sock_put(sk);
  85                         kfree(ra);
  86                         return 0;
  87                 }
  88         }
  89         if (!new_ra) {
  90                 write_unlock_bh(&ip6_ra_lock);
  91                 return -ENOBUFS;
  92         }
  93         new_ra->sk = sk;
  94         new_ra->sel = sel;
  95         new_ra->next = ra;
  96         *rap = new_ra;
  97         sock_hold(sk);
  98         write_unlock_bh(&ip6_ra_lock);
  99         return 0;
 100 }
 101
 102 struct ipv6_txoptions *ipv6_update_options(struct sock *sk,
 103                                            struct ipv6_txoptions *opt)
 104 {
 105         if (inet_sk(sk)->is_icsk) {
 106                 if (opt &&
 107                     !((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE)) &&
 108                     inet_sk(sk)->inet_daddr != LOOPBACK4_IPV6) {
 109                         struct inet_connection_sock *icsk = inet_csk(sk);
 110                         icsk->icsk_ext_hdr_len = opt->opt_flen + opt->opt_nflen;
 111                         icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie);
 112                 }
 113         }
 114         opt = xchg((__force struct ipv6_txoptions **)&inet6_sk(sk)->opt,
 115                    opt);
 116         sk_dst_reset(sk);
 117
 118         return opt;
 119 }
 120
 121 static bool setsockopt_needs_rtnl(int optname)
 122 {
 123         switch (optname) {
 124         case IPV6_ADDRFORM:
 125         case IPV6_ADD_MEMBERSHIP:
 126         case IPV6_DROP_MEMBERSHIP:
 127         case IPV6_JOIN_ANYCAST:
 128         case IPV6_LEAVE_ANYCAST:
 129         case MCAST_JOIN_GROUP:
 130         case MCAST_LEAVE_GROUP:
 131         case MCAST_JOIN_SOURCE_GROUP:
 132         case MCAST_LEAVE_SOURCE_GROUP:
 133         case MCAST_BLOCK_SOURCE:
 134         case MCAST_UNBLOCK_SOURCE:
 135         case MCAST_MSFILTER:
 136                 return true;
 137         }
 138         return false;
 139 }
 140
 141 static int copy_group_source_from_sockptr(struct group_source_req *greqs,
 142                 sockptr_t optval, int optlen)
 143 {
 144         if (in_compat_syscall()) {
 145                 struct compat_group_source_req gr32;
 146
 147                 if (optlen < sizeof(gr32))
 148                         return -EINVAL;
 149                 if (copy_from_sockptr(&gr32, optval, sizeof(gr32)))
 150                         return -EFAULT;
 151                 greqs->gsr_interface = gr32.gsr_interface;
 152                 greqs->gsr_group = gr32.gsr_group;
 153                 greqs->gsr_source = gr32.gsr_source;
 154         } else {
 155                 if (optlen < sizeof(*greqs))
 156                         return -EINVAL;
 157                 if (copy_from_sockptr(greqs, optval, sizeof(*greqs)))
 158                         return -EFAULT;
 159         }
 160
 161         return 0;
 162 }
 163
 164 static int do_ipv6_mcast_group_source(struct sock *sk, int optname,
 165                 sockptr_t optval, int optlen)
 166 {
 167         struct group_source_req greqs;
 168         int omode, add;
 169         int ret;
 170
 171         ret = copy_group_source_from_sockptr(&greqs, optval, optlen);
 172         if (ret)
 173                 return ret;
 174
 175         if (greqs.gsr_group.ss_family != AF_INET6 ||
 176             greqs.gsr_source.ss_family != AF_INET6)
 177                 return -EADDRNOTAVAIL;
 178
 179         if (optname == MCAST_BLOCK_SOURCE) {
 180                 omode = MCAST_EXCLUDE;
 181                 add = 1;
 182         } else if (optname == MCAST_UNBLOCK_SOURCE) {
 183                 omode = MCAST_EXCLUDE;
 184                 add = 0;
 185         } else if (optname == MCAST_JOIN_SOURCE_GROUP) {
 186                 struct sockaddr_in6 *psin6;
 187                 int retv;
 188
 189                 psin6 = (struct sockaddr_in6 *)&greqs.gsr_group;
 190                 retv = ipv6_sock_mc_join_ssm(sk, greqs.gsr_interface,
 191                                              &psin6->sin6_addr,
 192                                              MCAST_INCLUDE);
 193                 /* prior join w/ different source is ok */
 194                 if (retv && retv != -EADDRINUSE)
 195                         return retv;
 196                 omode = MCAST_INCLUDE;
 197                 add = 1;
 198         } else /* MCAST_LEAVE_SOURCE_GROUP */ {
 199                 omode = MCAST_INCLUDE;
 200                 add = 0;
 201         }
 202         return ip6_mc_source(add, omode, sk, &greqs);
 203 }
 204
 205 static int ipv6_set_mcast_msfilter(struct sock *sk, sockptr_t optval,
 206                 int optlen)
 207 {
 208         struct group_filter *gsf;
 209         int ret;
 210
 211         if (optlen < GROUP_FILTER_SIZE(0))
 212                 return -EINVAL;
 213         if (optlen > sysctl_optmem_max)
 214                 return -ENOBUFS;
 215
 216         gsf = memdup_sockptr(optval, optlen);
 217         if (IS_ERR(gsf))
 218                 return PTR_ERR(gsf);
 219
 220         /* numsrc >= (4G-140)/128 overflow in 32 bits */
 221         ret = -ENOBUFS;
 222         if (gsf->gf_numsrc >= 0x1ffffffU ||
 223             gsf->gf_numsrc > sysctl_mld_max_msf)
 224                 goto out_free_gsf;
 225
 226         ret = -EINVAL;
 227         if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen)
 228                 goto out_free_gsf;
 229
 230         ret = ip6_mc_msfilter(sk, gsf, gsf->gf_slist_flex);
 231 out_free_gsf:
 232         kfree(gsf);
 233         return ret;
 234 }
 235
 236 static int compat_ipv6_set_mcast_msfilter(struct sock *sk, sockptr_t optval,
 237                 int optlen)
 238 {
 239         const int size0 = offsetof(struct compat_group_filter, gf_slist_flex);
 240         struct compat_group_filter *gf32;
 241         void *p;
 242         int ret;
 243         int n;
 244
 245         if (optlen < size0)
 246                 return -EINVAL;
 247         if (optlen > sysctl_optmem_max - 4)
 248                 return -ENOBUFS;
 249
 250         p = kmalloc(optlen + 4, GFP_KERNEL);
 251         if (!p)
 252                 return -ENOMEM;
 253
 254         gf32 = p + 4; /* we want ->gf_group and ->gf_slist_flex aligned */
 255         ret = -EFAULT;
 256         if (copy_from_sockptr(gf32, optval, optlen))
 257                 goto out_free_p;
 258
 259         /* numsrc >= (4G-140)/128 overflow in 32 bits */
 260         ret = -ENOBUFS;
 261         n = gf32->gf_numsrc;
 262         if (n >= 0x1ffffffU || n > sysctl_mld_max_msf)
 263                 goto out_free_p;
 264
 265         ret = -EINVAL;
 266         if (offsetof(struct compat_group_filter, gf_slist_flex[n]) > optlen)
 267                 goto out_free_p;
 268
 269         ret = ip6_mc_msfilter(sk, &(struct group_filter){
 270                         .gf_interface = gf32->gf_interface,
 271                         .gf_group = gf32->gf_group,
 272                         .gf_fmode = gf32->gf_fmode,
 273                         .gf_numsrc = gf32->gf_numsrc}, gf32->gf_slist_flex);
 274
 275 out_free_p:
 276         kfree(p);
 277         return ret;
 278 }
 279
 280 static int ipv6_mcast_join_leave(struct sock *sk, int optname,
 281                 sockptr_t optval, int optlen)
 282 {
 283         struct sockaddr_in6 *psin6;
 284         struct group_req greq;
 285
 286         if (optlen < sizeof(greq))
 287                 return -EINVAL;
 288         if (copy_from_sockptr(&greq, optval, sizeof(greq)))
 289                 return -EFAULT;
 290
 291         if (greq.gr_group.ss_family != AF_INET6)
 292                 return -EADDRNOTAVAIL;
 293         psin6 = (struct sockaddr_in6 *)&greq.gr_group;
 294         if (optname == MCAST_JOIN_GROUP)
 295                 return ipv6_sock_mc_join(sk, greq.gr_interface,
 296                                          &psin6->sin6_addr);
 297         return ipv6_sock_mc_drop(sk, greq.gr_interface, &psin6->sin6_addr);
 298 }
 299
 300 static int compat_ipv6_mcast_join_leave(struct sock *sk, int optname,
 301                 sockptr_t optval, int optlen)
 302 {
 303         struct compat_group_req gr32;
 304         struct sockaddr_in6 *psin6;
 305
 306         if (optlen < sizeof(gr32))
 307                 return -EINVAL;
 308         if (copy_from_sockptr(&gr32, optval, sizeof(gr32)))
 309                 return -EFAULT;
 310
 311         if (gr32.gr_group.ss_family != AF_INET6)
 312                 return -EADDRNOTAVAIL;
 313         psin6 = (struct sockaddr_in6 *)&gr32.gr_group;
 314         if (optname == MCAST_JOIN_GROUP)
 315                 return ipv6_sock_mc_join(sk, gr32.gr_interface,
 316                                         &psin6->sin6_addr);
 317         return ipv6_sock_mc_drop(sk, gr32.gr_interface, &psin6->sin6_addr);
 318 }
 319
 320 static int ipv6_set_opt_hdr(struct sock *sk, int optname, sockptr_t optval,
 321                 int optlen)
 322 {
 323         struct ipv6_pinfo *np = inet6_sk(sk);
 324         struct ipv6_opt_hdr *new = NULL;
 325         struct net *net = sock_net(sk);
 326         struct ipv6_txoptions *opt;
 327         int err;
 328
 329         /* hop-by-hop / destination options are privileged option */
 330         if (optname != IPV6_RTHDR && !ns_capable(net->user_ns, CAP_NET_RAW))
 331                 return -EPERM;
 332
 333         /* remove any sticky options header with a zero option
 334          * length, per RFC3542.
 335          */
 336         if (optlen > 0) {
 337                 if (sockptr_is_null(optval))
 338                         return -EINVAL;
 339                 if (optlen < sizeof(struct ipv6_opt_hdr) ||
 340                     optlen & 0x7 ||
 341                     optlen > 8 * 255)
 342                         return -EINVAL;
 343
 344                 new = memdup_sockptr(optval, optlen);
 345                 if (IS_ERR(new))
 346                         return PTR_ERR(new);
 347                 if (unlikely(ipv6_optlen(new) > optlen)) {
 348                         kfree(new);
 349                         return -EINVAL;
 350                 }
 351         }
 352
 353         opt = rcu_dereference_protected(np->opt, lockdep_sock_is_held(sk));
 354         opt = ipv6_renew_options(sk, opt, optname, new);
 355         kfree(new);
 356         if (IS_ERR(opt))
 357                 return PTR_ERR(opt);
 358
 359         /* routing header option needs extra check */
 360         err = -EINVAL;
 361         if (optname == IPV6_RTHDR && opt && opt->srcrt) {
 362                 struct ipv6_rt_hdr *rthdr = opt->srcrt;
 363                 switch (rthdr->type) {
 364 #if IS_ENABLED(CONFIG_IPV6_MIP6)
 365                 case IPV6_SRCRT_TYPE_2:
 366                         if (rthdr->hdrlen != 2 || rthdr->segments_left != 1)
 367                                 goto sticky_done;
 368                         break;
 369 #endif
 370                 case IPV6_SRCRT_TYPE_4:
 371                 {
 372                         struct ipv6_sr_hdr *srh =
 373                                 (struct ipv6_sr_hdr *)opt->srcrt;
 374
 375                         if (!seg6_validate_srh(srh, optlen, false))
 376                                 goto sticky_done;
 377                         break;
 378                 }
 379                 default:
 380                         goto sticky_done;
 381                 }
 382         }
 383
 384         err = 0;
 385         opt = ipv6_update_options(sk, opt);
 386 sticky_done:
 387         if (opt) {
 388                 atomic_sub(opt->tot_len, &sk->sk_omem_alloc);
 389                 txopt_put(opt);
 390         }
 391         return err;
 392 }
 393
 394 static int do_ipv6_setsockopt(struct sock *sk, int level, int optname,
 395                    sockptr_t optval, unsigned int optlen)
 396 {
 397         struct ipv6_pinfo *np = inet6_sk(sk);
 398         struct net *net = sock_net(sk);
 399         int val, valbool;
 400         int retv = -ENOPROTOOPT;
 401         bool needs_rtnl = setsockopt_needs_rtnl(optname);
 402
 403         if (sockptr_is_null(optval))
 404                 val = 0;
 405         else {
 406                 if (optlen >= sizeof(int)) {
 407                         if (copy_from_sockptr(&val, optval, sizeof(val)))
 408                                 return -EFAULT;
 409                 } else
 410                         val = 0;
 411         }
 412
 413         valbool = (val != 0);
 414
 415         if (ip6_mroute_opt(optname))
 416                 return ip6_mroute_setsockopt(sk, optname, optval, optlen);
 417
 418         if (needs_rtnl)
 419                 rtnl_lock();
 420         lock_sock(sk);
 421
 422         switch (optname) {
 423
 424         case IPV6_ADDRFORM:
 425                 if (optlen < sizeof(int))
 426                         goto e_inval;
 427                 if (val == PF_INET) {
 428                         struct ipv6_txoptions *opt;
 429                         struct sk_buff *pktopt;
 430
 431                         if (sk->sk_type == SOCK_RAW)
 432                                 break;
 433
 434                         if (sk->sk_protocol == IPPROTO_UDP ||
 435                             sk->sk_protocol == IPPROTO_UDPLITE) {
 436                                 struct udp_sock *up = udp_sk(sk);
 437                                 if (up->pending == AF_INET6) {
 438                                         retv = -EBUSY;
 439                                         break;
 440                                 }
 441                         } else if (sk->sk_protocol == IPPROTO_TCP) {
 442                                 if (sk->sk_prot != &tcpv6_prot) {
 443                                         retv = -EBUSY;
 444                                         break;
 445                                 }
 446                         } else {
 447                                 break;
 448                         }
 449
 450                         if (sk->sk_state != TCP_ESTABLISHED) {
 451                                 retv = -ENOTCONN;
 452                                 break;
 453                         }
 454
 455                         if (ipv6_only_sock(sk) ||
 456                             !ipv6_addr_v4mapped(&sk->sk_v6_daddr)) {
 457                                 retv = -EADDRNOTAVAIL;
 458                                 break;
 459                         }
 460
 461                         fl6_free_socklist(sk);
 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
 475                                 sock_prot_inuse_add(net, sk->sk_prot, -1);
 476                                 sock_prot_inuse_add(net, &tcp_prot, 1);
 477
 478                                 /* Paired with READ_ONCE(sk->sk_prot) in net/ipv6/af_inet6.c */
 479                                 WRITE_ONCE(sk->sk_prot, &tcp_prot);
 480                                 icsk->icsk_af_ops = &ipv4_specific;
 481                                 sk->sk_socket->ops = &inet_stream_ops;
 482                                 sk->sk_family = PF_INET;
 483                                 tcp_sync_mss(sk, icsk->icsk_pmtu_cookie);
 484                         } else {
 485                                 struct proto *prot = &udp_prot;
 486
 487                                 if (sk->sk_protocol == IPPROTO_UDPLITE)
 488                                         prot = &udplite_prot;
 489
 490                                 sock_prot_inuse_add(net, sk->sk_prot, -1);
 491                                 sock_prot_inuse_add(net, prot, 1);
 492
 493                                 /* Paired with READ_ONCE(sk->sk_prot) in net/ipv6/af_inet6.c */
 494                                 WRITE_ONCE(sk->sk_prot, prot);
 495                                 sk->sk_socket->ops = &inet_dgram_ops;
 496                                 sk->sk_family = PF_INET;
 497                         }
 498                         opt = xchg((__force struct ipv6_txoptions **)&np->opt,
 499                                    NULL);
 500                         if (opt) {
 501                                 atomic_sub(opt->tot_len, &sk->sk_omem_alloc);
 502                                 txopt_put(opt);
 503                         }
 504                         pktopt = xchg(&np->pktoptions, NULL);
 505                         kfree_skb(pktopt);
 506
 507                         /*
 508                          * ... and add it to the refcnt debug socks count
 509                          * in the new family. -acme
 510                          */
 511                         sk_refcnt_debug_inc(sk);
 512                         module_put(THIS_MODULE);
 513                         retv = 0;
 514                         break;
 515                 }
 516                 goto e_inval;
 517
 518         case IPV6_V6ONLY:
 519                 if (optlen < sizeof(int) ||
 520                     inet_sk(sk)->inet_num)
 521                         goto e_inval;
 522                 sk->sk_ipv6only = valbool;
 523                 retv = 0;
 524                 break;
 525
 526         case IPV6_RECVPKTINFO:
 527                 if (optlen < sizeof(int))
 528                         goto e_inval;
 529                 np->rxopt.bits.rxinfo = valbool;
 530                 retv = 0;
 531                 break;
 532
 533         case IPV6_2292PKTINFO:
 534                 if (optlen < sizeof(int))
 535                         goto e_inval;
 536                 np->rxopt.bits.rxoinfo = valbool;
 537                 retv = 0;
 538                 break;
 539
 540         case IPV6_RECVHOPLIMIT:
 541                 if (optlen < sizeof(int))
 542                         goto e_inval;
 543                 np->rxopt.bits.rxhlim = valbool;
 544                 retv = 0;
 545                 break;
 546
 547         case IPV6_2292HOPLIMIT:
 548                 if (optlen < sizeof(int))
 549                         goto e_inval;
 550                 np->rxopt.bits.rxohlim = valbool;
 551                 retv = 0;
 552                 break;
 553
 554         case IPV6_RECVRTHDR:
 555                 if (optlen < sizeof(int))
 556                         goto e_inval;
 557                 np->rxopt.bits.srcrt = valbool;
 558                 retv = 0;
 559                 break;
 560
 561         case IPV6_2292RTHDR:
 562                 if (optlen < sizeof(int))
 563                         goto e_inval;
 564                 np->rxopt.bits.osrcrt = valbool;
 565                 retv = 0;
 566                 break;
 567
 568         case IPV6_RECVHOPOPTS:
 569                 if (optlen < sizeof(int))
 570                         goto e_inval;
 571                 np->rxopt.bits.hopopts = valbool;
 572                 retv = 0;
 573                 break;
 574
 575         case IPV6_2292HOPOPTS:
 576                 if (optlen < sizeof(int))
 577                         goto e_inval;
 578                 np->rxopt.bits.ohopopts = valbool;
 579                 retv = 0;
 580                 break;
 581
 582         case IPV6_RECVDSTOPTS:
 583                 if (optlen < sizeof(int))
 584                         goto e_inval;
 585                 np->rxopt.bits.dstopts = valbool;
 586                 retv = 0;
 587                 break;
 588
 589         case IPV6_2292DSTOPTS:
 590                 if (optlen < sizeof(int))
 591                         goto e_inval;
 592                 np->rxopt.bits.odstopts = valbool;
 593                 retv = 0;
 594                 break;
 595
 596         case IPV6_TCLASS:
 597                 if (optlen < sizeof(int))
 598                         goto e_inval;
 599                 if (val < -1 || val > 0xff)
 600                         goto e_inval;
 601                 /* RFC 3542, 6.5: default traffic class of 0x0 */
 602                 if (val == -1)
 603                         val = 0;
 604                 if (sk->sk_type == SOCK_STREAM) {
 605                         val &= ~INET_ECN_MASK;
 606                         val |= np->tclass & INET_ECN_MASK;
 607                 }
 608                 if (np->tclass != val) {
 609                         np->tclass = val;
 610                         sk_dst_reset(sk);
 611                 }
 612                 retv = 0;
 613                 break;
 614
 615         case IPV6_RECVTCLASS:
 616                 if (optlen < sizeof(int))
 617                         goto e_inval;
 618                 np->rxopt.bits.rxtclass = valbool;
 619                 retv = 0;
 620                 break;
 621
 622         case IPV6_FLOWINFO:
 623                 if (optlen < sizeof(int))
 624                         goto e_inval;
 625                 np->rxopt.bits.rxflow = valbool;
 626                 retv = 0;
 627                 break;
 628
 629         case IPV6_RECVPATHMTU:
 630                 if (optlen < sizeof(int))
 631                         goto e_inval;
 632                 np->rxopt.bits.rxpmtu = valbool;
 633                 retv = 0;
 634                 break;
 635
 636         case IPV6_TRANSPARENT:
 637                 if (valbool && !ns_capable(net->user_ns, CAP_NET_RAW) &&
 638                     !ns_capable(net->user_ns, CAP_NET_ADMIN)) {
 639                         retv = -EPERM;
 640                         break;
 641                 }
 642                 if (optlen < sizeof(int))
 643                         goto e_inval;
 644                 /* we don't have a separate transparent bit for IPV6 we use the one in the IPv4 socket */
 645                 inet_sk(sk)->transparent = valbool;
 646                 retv = 0;
 647                 break;
 648
 649         case IPV6_FREEBIND:
 650                 if (optlen < sizeof(int))
 651                         goto e_inval;
 652                 /* we also don't have a separate freebind bit for IPV6 */
 653                 inet_sk(sk)->freebind = valbool;
 654                 retv = 0;
 655                 break;
 656
 657         case IPV6_RECVORIGDSTADDR:
 658                 if (optlen < sizeof(int))
 659                         goto e_inval;
 660                 np->rxopt.bits.rxorigdstaddr = valbool;
 661                 retv = 0;
 662                 break;
 663
 664         case IPV6_HOPOPTS:
 665         case IPV6_RTHDRDSTOPTS:
 666         case IPV6_RTHDR:
 667         case IPV6_DSTOPTS:
 668                 retv = ipv6_set_opt_hdr(sk, optname, optval, optlen);
 669                 break;
 670
 671         case IPV6_PKTINFO:
 672         {
 673                 struct in6_pktinfo pkt;
 674
 675                 if (optlen == 0)
 676                         goto e_inval;
 677                 else if (optlen < sizeof(struct in6_pktinfo) ||
 678                          sockptr_is_null(optval))
 679                         goto e_inval;
 680
 681                 if (copy_from_sockptr(&pkt, optval, sizeof(pkt))) {
 682                         retv = -EFAULT;
 683                         break;
 684                 }
 685                 if (!sk_dev_equal_l3scope(sk, pkt.ipi6_ifindex))
 686                         goto e_inval;
 687
 688                 np->sticky_pktinfo.ipi6_ifindex = pkt.ipi6_ifindex;
 689                 np->sticky_pktinfo.ipi6_addr = pkt.ipi6_addr;
 690                 retv = 0;
 691                 break;
 692         }
 693
 694         case IPV6_2292PKTOPTIONS:
 695         {
 696                 struct ipv6_txoptions *opt = NULL;
 697                 struct msghdr msg;
 698                 struct flowi6 fl6;
 699                 struct ipcm6_cookie ipc6;
 700
 701                 memset(&fl6, 0, sizeof(fl6));
 702                 fl6.flowi6_oif = sk->sk_bound_dev_if;
 703                 fl6.flowi6_mark = sk->sk_mark;
 704
 705                 if (optlen == 0)
 706                         goto update;
 707
 708                 /* 1K is probably excessive
 709                  * 1K is surely not enough, 2K per standard header is 16K.
 710                  */
 711                 retv = -EINVAL;
 712                 if (optlen > 64*1024)
 713                         break;
 714
 715                 opt = sock_kmalloc(sk, sizeof(*opt) + optlen, GFP_KERNEL);
 716                 retv = -ENOBUFS;
 717                 if (!opt)
 718                         break;
 719
 720                 memset(opt, 0, sizeof(*opt));
 721                 refcount_set(&opt->refcnt, 1);
 722                 opt->tot_len = sizeof(*opt) + optlen;
 723                 retv = -EFAULT;
 724                 if (copy_from_sockptr(opt + 1, optval, optlen))
 725                         goto done;
 726
 727                 msg.msg_controllen = optlen;
 728                 msg.msg_control = (void *)(opt+1);
 729                 ipc6.opt = opt;
 730
 731                 retv = ip6_datagram_send_ctl(net, sk, &msg, &fl6, &ipc6);
 732                 if (retv)
 733                         goto done;
 734 update:
 735                 retv = 0;
 736                 opt = ipv6_update_options(sk, opt);
 737 done:
 738                 if (opt) {
 739                         atomic_sub(opt->tot_len, &sk->sk_omem_alloc);
 740                         txopt_put(opt);
 741                 }
 742                 break;
 743         }
 744         case IPV6_UNICAST_HOPS:
 745                 if (optlen < sizeof(int))
 746                         goto e_inval;
 747                 if (val > 255 || val < -1)
 748                         goto e_inval;
 749                 np->hop_limit = val;
 750                 retv = 0;
 751                 break;
 752
 753         case IPV6_MULTICAST_HOPS:
 754                 if (sk->sk_type == SOCK_STREAM)
 755                         break;
 756                 if (optlen < sizeof(int))
 757                         goto e_inval;
 758                 if (val > 255 || val < -1)
 759                         goto e_inval;
 760                 np->mcast_hops = (val == -1 ? IPV6_DEFAULT_MCASTHOPS : val);
 761                 retv = 0;
 762                 break;
 763
 764         case IPV6_MULTICAST_LOOP:
 765                 if (optlen < sizeof(int))
 766                         goto e_inval;
 767                 if (val != valbool)
 768                         goto e_inval;
 769                 np->mc_loop = valbool;
 770                 retv = 0;
 771                 break;
 772
 773         case IPV6_UNICAST_IF:
 774         {
 775                 struct net_device *dev = NULL;
 776                 int ifindex;
 777
 778                 if (optlen != sizeof(int))
 779                         goto e_inval;
 780
 781                 ifindex = (__force int)ntohl((__force __be32)val);
 782                 if (ifindex == 0) {
 783                         np->ucast_oif = 0;
 784                         retv = 0;
 785                         break;
 786                 }
 787
 788                 dev = dev_get_by_index(net, ifindex);
 789                 retv = -EADDRNOTAVAIL;
 790                 if (!dev)
 791                         break;
 792                 dev_put(dev);
 793
 794                 retv = -EINVAL;
 795                 if (sk->sk_bound_dev_if)
 796                         break;
 797
 798                 np->ucast_oif = ifindex;
 799                 retv = 0;
 800                 break;
 801         }
 802
 803         case IPV6_MULTICAST_IF:
 804                 if (sk->sk_type == SOCK_STREAM)
 805                         break;
 806                 if (optlen < sizeof(int))
 807                         goto e_inval;
 808
 809                 if (val) {
 810                         struct net_device *dev;
 811                         int midx;
 812
 813                         rcu_read_lock();
 814
 815                         dev = dev_get_by_index_rcu(net, val);
 816                         if (!dev) {
 817                                 rcu_read_unlock();
 818                                 retv = -ENODEV;
 819                                 break;
 820                         }
 821                         midx = l3mdev_master_ifindex_rcu(dev);
 822
 823                         rcu_read_unlock();
 824
 825                         if (sk->sk_bound_dev_if &&
 826                             sk->sk_bound_dev_if != val &&
 827                             (!midx || midx != sk->sk_bound_dev_if))
 828                                 goto e_inval;
 829                 }
 830                 np->mcast_oif = val;
 831                 retv = 0;
 832                 break;
 833         case IPV6_ADD_MEMBERSHIP:
 834         case IPV6_DROP_MEMBERSHIP:
 835         {
 836                 struct ipv6_mreq mreq;
 837
 838                 if (optlen < sizeof(struct ipv6_mreq))
 839                         goto e_inval;
 840
 841                 retv = -EPROTO;
 842                 if (inet_sk(sk)->is_icsk)
 843                         break;
 844
 845                 retv = -EFAULT;
 846                 if (copy_from_sockptr(&mreq, optval, sizeof(struct ipv6_mreq)))
 847                         break;
 848
 849                 if (optname == IPV6_ADD_MEMBERSHIP)
 850                         retv = ipv6_sock_mc_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr);
 851                 else
 852                         retv = ipv6_sock_mc_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_multiaddr);
 853                 break;
 854         }
 855         case IPV6_JOIN_ANYCAST:
 856         case IPV6_LEAVE_ANYCAST:
 857         {
 858                 struct ipv6_mreq mreq;
 859
 860                 if (optlen < sizeof(struct ipv6_mreq))
 861                         goto e_inval;
 862
 863                 retv = -EFAULT;
 864                 if (copy_from_sockptr(&mreq, optval, sizeof(struct ipv6_mreq)))
 865                         break;
 866
 867                 if (optname == IPV6_JOIN_ANYCAST)
 868                         retv = ipv6_sock_ac_join(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_acaddr);
 869                 else
 870                         retv = ipv6_sock_ac_drop(sk, mreq.ipv6mr_ifindex, &mreq.ipv6mr_acaddr);
 871                 break;
 872         }
 873         case IPV6_MULTICAST_ALL:
 874                 if (optlen < sizeof(int))
 875                         goto e_inval;
 876                 np->mc_all = valbool;
 877                 retv = 0;
 878                 break;
 879
 880         case MCAST_JOIN_GROUP:
 881         case MCAST_LEAVE_GROUP:
 882                 if (in_compat_syscall())
 883                         retv = compat_ipv6_mcast_join_leave(sk, optname, optval,
 884                                                             optlen);
 885                 else
 886                         retv = ipv6_mcast_join_leave(sk, optname, optval,
 887                                                      optlen);
 888                 break;
 889         case MCAST_JOIN_SOURCE_GROUP:
 890         case MCAST_LEAVE_SOURCE_GROUP:
 891         case MCAST_BLOCK_SOURCE:
 892         case MCAST_UNBLOCK_SOURCE:
 893                 retv = do_ipv6_mcast_group_source(sk, optname, optval, optlen);
 894                 break;
 895         case MCAST_MSFILTER:
 896                 if (in_compat_syscall())
 897                         retv = compat_ipv6_set_mcast_msfilter(sk, optval,
 898                                                               optlen);
 899                 else
 900                         retv = ipv6_set_mcast_msfilter(sk, optval, optlen);
 901                 break;
 902         case IPV6_ROUTER_ALERT:
 903                 if (optlen < sizeof(int))
 904                         goto e_inval;
 905                 retv = ip6_ra_control(sk, val);
 906                 break;
 907         case IPV6_ROUTER_ALERT_ISOLATE:
 908                 if (optlen < sizeof(int))
 909                         goto e_inval;
 910                 np->rtalert_isolate = valbool;
 911                 retv = 0;
 912                 break;
 913         case IPV6_MTU_DISCOVER:
 914                 if (optlen < sizeof(int))
 915                         goto e_inval;
 916                 if (val < IPV6_PMTUDISC_DONT || val > IPV6_PMTUDISC_OMIT)
 917                         goto e_inval;
 918                 np->pmtudisc = val;
 919                 retv = 0;
 920                 break;
 921         case IPV6_MTU:
 922                 if (optlen < sizeof(int))
 923                         goto e_inval;
 924                 if (val && val < IPV6_MIN_MTU)
 925                         goto e_inval;
 926                 np->frag_size = val;
 927                 retv = 0;
 928                 break;
 929         case IPV6_RECVERR:
 930                 if (optlen < sizeof(int))
 931                         goto e_inval;
 932                 np->recverr = valbool;
 933                 if (!val)
 934                         skb_queue_purge(&sk->sk_error_queue);
 935                 retv = 0;
 936                 break;
 937         case IPV6_FLOWINFO_SEND:
 938                 if (optlen < sizeof(int))
 939                         goto e_inval;
 940                 np->sndflow = valbool;
 941                 retv = 0;
 942                 break;
 943         case IPV6_FLOWLABEL_MGR:
 944                 retv = ipv6_flowlabel_opt(sk, optval, optlen);
 945                 break;
 946         case IPV6_IPSEC_POLICY:
 947         case IPV6_XFRM_POLICY:
 948                 retv = -EPERM;
 949                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 950                         break;
 951                 retv = xfrm_user_policy(sk, optname, optval, optlen);
 952                 break;
 953
 954         case IPV6_ADDR_PREFERENCES:
 955                 if (optlen < sizeof(int))
 956                         goto e_inval;
 957                 retv = __ip6_sock_set_addr_preferences(sk, val);
 958                 break;
 959         case IPV6_MINHOPCOUNT:
 960                 if (optlen < sizeof(int))
 961                         goto e_inval;
 962                 if (val < 0 || val > 255)
 963                         goto e_inval;
 964
 965                 if (val)
 966                         static_branch_enable(&ip6_min_hopcount);
 967
 968                 /* tcp_v6_err() and tcp_v6_rcv() might read min_hopcount
 969                  * while we are changing it.
 970                  */
 971                 WRITE_ONCE(np->min_hopcount, val);
 972                 retv = 0;
 973                 break;
 974         case IPV6_DONTFRAG:
 975                 np->dontfrag = valbool;
 976                 retv = 0;
 977                 break;
 978         case IPV6_AUTOFLOWLABEL:
 979                 np->autoflowlabel = valbool;
 980                 np->autoflowlabel_set = 1;
 981                 retv = 0;
 982                 break;
 983         case IPV6_RECVFRAGSIZE:
 984                 np->rxopt.bits.recvfragsize = valbool;
 985                 retv = 0;
 986                 break;
 987         case IPV6_RECVERR_RFC4884:
 988                 if (optlen < sizeof(int))
 989                         goto e_inval;
 990                 if (val < 0 || val > 1)
 991                         goto e_inval;
 992                 np->recverr_rfc4884 = valbool;
 993                 retv = 0;
 994                 break;
 995         }
 996
 997         release_sock(sk);
 998         if (needs_rtnl)
 999                 rtnl_unlock();
1000
1001         return retv;
1002
1003 e_inval:
1004         release_sock(sk);
1005         if (needs_rtnl)
1006                 rtnl_unlock();
1007         return -EINVAL;
1008 }
1009
1010 int ipv6_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
1011                     unsigned int optlen)
1012 {
1013         int err;
1014
1015         if (level == SOL_IP && sk->sk_type != SOCK_RAW)
1016                 return udp_prot.setsockopt(sk, level, optname, optval, optlen);
1017
1018         if (level != SOL_IPV6)
1019                 return -ENOPROTOOPT;
1020
1021         err = do_ipv6_setsockopt(sk, level, optname, optval, optlen);
1022 #ifdef CONFIG_NETFILTER
1023         /* we need to exclude all possible ENOPROTOOPTs except default case */
1024         if (err == -ENOPROTOOPT && optname != IPV6_IPSEC_POLICY &&
1025                         optname != IPV6_XFRM_POLICY)
1026                 err = nf_setsockopt(sk, PF_INET6, optname, optval, optlen);
1027 #endif
1028         return err;
1029 }
1030 EXPORT_SYMBOL(ipv6_setsockopt);
1031
1032 static int ipv6_getsockopt_sticky(struct sock *sk, struct ipv6_txoptions *opt,
1033                                   int optname, char __user *optval, int len)
1034 {
1035         struct ipv6_opt_hdr *hdr;
1036
1037         if (!opt)
1038                 return 0;
1039
1040         switch (optname) {
1041         case IPV6_HOPOPTS:
1042                 hdr = opt->hopopt;
1043                 break;
1044         case IPV6_RTHDRDSTOPTS:
1045                 hdr = opt->dst0opt;
1046                 break;
1047         case IPV6_RTHDR:
1048                 hdr = (struct ipv6_opt_hdr *)opt->srcrt;
1049                 break;
1050         case IPV6_DSTOPTS:
1051                 hdr = opt->dst1opt;
1052                 break;
1053         default:
1054                 return -EINVAL; /* should not happen */
1055         }
1056
1057         if (!hdr)
1058                 return 0;
1059
1060         len = min_t(unsigned int, len, ipv6_optlen(hdr));
1061         if (copy_to_user(optval, hdr, len))
1062                 return -EFAULT;
1063         return len;
1064 }
1065
1066 static int ipv6_get_msfilter(struct sock *sk, void __user *optval,
1067                 int __user *optlen, int len)
1068 {
1069         const int size0 = offsetof(struct group_filter, gf_slist_flex);
1070         struct group_filter __user *p = optval;
1071         struct group_filter gsf;
1072         int num;
1073         int err;
1074
1075         if (len < size0)
1076                 return -EINVAL;
1077         if (copy_from_user(&gsf, p, size0))
1078                 return -EFAULT;
1079         if (gsf.gf_group.ss_family != AF_INET6)
1080                 return -EADDRNOTAVAIL;
1081         num = gsf.gf_numsrc;
1082         lock_sock(sk);
1083         err = ip6_mc_msfget(sk, &gsf, p->gf_slist_flex);
1084         if (!err) {
1085                 if (num > gsf.gf_numsrc)
1086                         num = gsf.gf_numsrc;
1087                 if (put_user(GROUP_FILTER_SIZE(num), optlen) ||
1088                     copy_to_user(p, &gsf, size0))
1089                         err = -EFAULT;
1090         }
1091         release_sock(sk);
1092         return err;
1093 }
1094
1095 static int compat_ipv6_get_msfilter(struct sock *sk, void __user *optval,
1096                 int __user *optlen)
1097 {
1098         const int size0 = offsetof(struct compat_group_filter, gf_slist_flex);
1099         struct compat_group_filter __user *p = optval;
1100         struct compat_group_filter gf32;
1101         struct group_filter gf;
1102         int len, err;
1103         int num;
1104
1105         if (get_user(len, optlen))
1106                 return -EFAULT;
1107         if (len < size0)
1108                 return -EINVAL;
1109
1110         if (copy_from_user(&gf32, p, size0))
1111                 return -EFAULT;
1112         gf.gf_interface = gf32.gf_interface;
1113         gf.gf_fmode = gf32.gf_fmode;
1114         num = gf.gf_numsrc = gf32.gf_numsrc;
1115         gf.gf_group = gf32.gf_group;
1116
1117         if (gf.gf_group.ss_family != AF_INET6)
1118                 return -EADDRNOTAVAIL;
1119
1120         lock_sock(sk);
1121         err = ip6_mc_msfget(sk, &gf, p->gf_slist_flex);
1122         release_sock(sk);
1123         if (err)
1124                 return err;
1125         if (num > gf.gf_numsrc)
1126                 num = gf.gf_numsrc;
1127         len = GROUP_FILTER_SIZE(num) - (sizeof(gf)-sizeof(gf32));
1128         if (put_user(len, optlen) ||
1129             put_user(gf.gf_fmode, &p->gf_fmode) ||
1130             put_user(gf.gf_numsrc, &p->gf_numsrc))
1131                 return -EFAULT;
1132         return 0;
1133 }
1134
1135 static int do_ipv6_getsockopt(struct sock *sk, int level, int optname,
1136                     char __user *optval, int __user *optlen, unsigned int flags)
1137 {
1138         struct ipv6_pinfo *np = inet6_sk(sk);
1139         int len;
1140         int val;
1141
1142         if (ip6_mroute_opt(optname))
1143                 return ip6_mroute_getsockopt(sk, optname, optval, optlen);
1144
1145         if (get_user(len, optlen))
1146                 return -EFAULT;
1147         switch (optname) {
1148         case IPV6_ADDRFORM:
1149                 if (sk->sk_protocol != IPPROTO_UDP &&
1150                     sk->sk_protocol != IPPROTO_UDPLITE &&
1151                     sk->sk_protocol != IPPROTO_TCP)
1152                         return -ENOPROTOOPT;
1153                 if (sk->sk_state != TCP_ESTABLISHED)
1154                         return -ENOTCONN;
1155                 val = sk->sk_family;
1156                 break;
1157         case MCAST_MSFILTER:
1158                 if (in_compat_syscall())
1159                         return compat_ipv6_get_msfilter(sk, optval, optlen);
1160                 return ipv6_get_msfilter(sk, optval, optlen, len);
1161         case IPV6_2292PKTOPTIONS:
1162         {
1163                 struct msghdr msg;
1164                 struct sk_buff *skb;
1165
1166                 if (sk->sk_type != SOCK_STREAM)
1167                         return -ENOPROTOOPT;
1168
1169                 msg.msg_control_user = optval;
1170                 msg.msg_controllen = len;
1171                 msg.msg_flags = flags;
1172                 msg.msg_control_is_user = true;
1173
1174                 lock_sock(sk);
1175                 skb = np->pktoptions;
1176                 if (skb)
1177                         ip6_datagram_recv_ctl(sk, &msg, skb);
1178                 release_sock(sk);
1179                 if (!skb) {
1180                         if (np->rxopt.bits.rxinfo) {
1181                                 struct in6_pktinfo src_info;
1182                                 src_info.ipi6_ifindex = np->mcast_oif ? np->mcast_oif :
1183                                         np->sticky_pktinfo.ipi6_ifindex;
1184                                 src_info.ipi6_addr = np->mcast_oif ? sk->sk_v6_daddr : np->sticky_pktinfo.ipi6_addr;
1185                                 put_cmsg(&msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info);
1186                         }
1187                         if (np->rxopt.bits.rxhlim) {
1188                                 int hlim = np->mcast_hops;
1189                                 put_cmsg(&msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
1190                         }
1191                         if (np->rxopt.bits.rxtclass) {
1192                                 int tclass = (int)ip6_tclass(np->rcv_flowinfo);
1193
1194                                 put_cmsg(&msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
1195                         }
1196                         if (np->rxopt.bits.rxoinfo) {
1197                                 struct in6_pktinfo src_info;
1198                                 src_info.ipi6_ifindex = np->mcast_oif ? np->mcast_oif :
1199                                         np->sticky_pktinfo.ipi6_ifindex;
1200                                 src_info.ipi6_addr = np->mcast_oif ? sk->sk_v6_daddr :
1201                                                                      np->sticky_pktinfo.ipi6_addr;
1202                                 put_cmsg(&msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
1203                         }
1204                         if (np->rxopt.bits.rxohlim) {
1205                                 int hlim = np->mcast_hops;
1206                                 put_cmsg(&msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
1207                         }
1208                         if (np->rxopt.bits.rxflow) {
1209                                 __be32 flowinfo = np->rcv_flowinfo;
1210
1211                                 put_cmsg(&msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
1212                         }
1213                 }
1214                 len -= msg.msg_controllen;
1215                 return put_user(len, optlen);
1216         }
1217         case IPV6_MTU:
1218         {
1219                 struct dst_entry *dst;
1220
1221                 val = 0;
1222                 rcu_read_lock();
1223                 dst = __sk_dst_get(sk);
1224                 if (dst)
1225                         val = dst_mtu(dst);
1226                 rcu_read_unlock();
1227                 if (!val)
1228                         return -ENOTCONN;
1229                 break;
1230         }
1231
1232         case IPV6_V6ONLY:
1233                 val = sk->sk_ipv6only;
1234                 break;
1235
1236         case IPV6_RECVPKTINFO:
1237                 val = np->rxopt.bits.rxinfo;
1238                 break;
1239
1240         case IPV6_2292PKTINFO:
1241                 val = np->rxopt.bits.rxoinfo;
1242                 break;
1243
1244         case IPV6_RECVHOPLIMIT:
1245                 val = np->rxopt.bits.rxhlim;
1246                 break;
1247
1248         case IPV6_2292HOPLIMIT:
1249                 val = np->rxopt.bits.rxohlim;
1250                 break;
1251
1252         case IPV6_RECVRTHDR:
1253                 val = np->rxopt.bits.srcrt;
1254                 break;
1255
1256         case IPV6_2292RTHDR:
1257                 val = np->rxopt.bits.osrcrt;
1258                 break;
1259
1260         case IPV6_HOPOPTS:
1261         case IPV6_RTHDRDSTOPTS:
1262         case IPV6_RTHDR:
1263         case IPV6_DSTOPTS:
1264         {
1265                 struct ipv6_txoptions *opt;
1266
1267                 lock_sock(sk);
1268                 opt = rcu_dereference_protected(np->opt,
1269                                                 lockdep_sock_is_held(sk));
1270                 len = ipv6_getsockopt_sticky(sk, opt, optname, optval, len);
1271                 release_sock(sk);
1272                 /* check if ipv6_getsockopt_sticky() returns err code */
1273                 if (len < 0)
1274                         return len;
1275                 return put_user(len, optlen);
1276         }
1277
1278         case IPV6_RECVHOPOPTS:
1279                 val = np->rxopt.bits.hopopts;
1280                 break;
1281
1282         case IPV6_2292HOPOPTS:
1283                 val = np->rxopt.bits.ohopopts;
1284                 break;
1285
1286         case IPV6_RECVDSTOPTS:
1287                 val = np->rxopt.bits.dstopts;
1288                 break;
1289
1290         case IPV6_2292DSTOPTS:
1291                 val = np->rxopt.bits.odstopts;
1292                 break;
1293
1294         case IPV6_TCLASS:
1295                 val = np->tclass;
1296                 break;
1297
1298         case IPV6_RECVTCLASS:
1299                 val = np->rxopt.bits.rxtclass;
1300                 break;
1301
1302         case IPV6_FLOWINFO:
1303                 val = np->rxopt.bits.rxflow;
1304                 break;
1305
1306         case IPV6_RECVPATHMTU:
1307                 val = np->rxopt.bits.rxpmtu;
1308                 break;
1309
1310         case IPV6_PATHMTU:
1311         {
1312                 struct dst_entry *dst;
1313                 struct ip6_mtuinfo mtuinfo;
1314
1315                 if (len < sizeof(mtuinfo))
1316                         return -EINVAL;
1317
1318                 len = sizeof(mtuinfo);
1319                 memset(&mtuinfo, 0, sizeof(mtuinfo));
1320
1321                 rcu_read_lock();
1322                 dst = __sk_dst_get(sk);
1323                 if (dst)
1324                         mtuinfo.ip6m_mtu = dst_mtu(dst);
1325                 rcu_read_unlock();
1326                 if (!mtuinfo.ip6m_mtu)
1327                         return -ENOTCONN;
1328
1329                 if (put_user(len, optlen))
1330                         return -EFAULT;
1331                 if (copy_to_user(optval, &mtuinfo, len))
1332                         return -EFAULT;
1333
1334                 return 0;
1335         }
1336
1337         case IPV6_TRANSPARENT:
1338                 val = inet_sk(sk)->transparent;
1339                 break;
1340
1341         case IPV6_FREEBIND:
1342                 val = inet_sk(sk)->freebind;
1343                 break;
1344
1345         case IPV6_RECVORIGDSTADDR:
1346                 val = np->rxopt.bits.rxorigdstaddr;
1347                 break;
1348
1349         case IPV6_UNICAST_HOPS:
1350         case IPV6_MULTICAST_HOPS:
1351         {
1352                 struct dst_entry *dst;
1353
1354                 if (optname == IPV6_UNICAST_HOPS)
1355                         val = np->hop_limit;
1356                 else
1357                         val = np->mcast_hops;
1358
1359                 if (val < 0) {
1360                         rcu_read_lock();
1361                         dst = __sk_dst_get(sk);
1362                         if (dst)
1363                                 val = ip6_dst_hoplimit(dst);
1364                         rcu_read_unlock();
1365                 }
1366
1367                 if (val < 0)
1368                         val = sock_net(sk)->ipv6.devconf_all->hop_limit;
1369                 break;
1370         }
1371
1372         case IPV6_MULTICAST_LOOP:
1373                 val = np->mc_loop;
1374                 break;
1375
1376         case IPV6_MULTICAST_IF:
1377                 val = np->mcast_oif;
1378                 break;
1379
1380         case IPV6_MULTICAST_ALL:
1381                 val = np->mc_all;
1382                 break;
1383
1384         case IPV6_UNICAST_IF:
1385                 val = (__force int)htonl((__u32) np->ucast_oif);
1386                 break;
1387
1388         case IPV6_MTU_DISCOVER:
1389                 val = np->pmtudisc;
1390                 break;
1391
1392         case IPV6_RECVERR:
1393                 val = np->recverr;
1394                 break;
1395
1396         case IPV6_FLOWINFO_SEND:
1397                 val = np->sndflow;
1398                 break;
1399
1400         case IPV6_FLOWLABEL_MGR:
1401         {
1402                 struct in6_flowlabel_req freq;
1403                 int flags;
1404
1405                 if (len < sizeof(freq))
1406                         return -EINVAL;
1407
1408                 if (copy_from_user(&freq, optval, sizeof(freq)))
1409                         return -EFAULT;
1410
1411                 if (freq.flr_action != IPV6_FL_A_GET)
1412                         return -EINVAL;
1413
1414                 len = sizeof(freq);
1415                 flags = freq.flr_flags;
1416
1417                 memset(&freq, 0, sizeof(freq));
1418
1419                 val = ipv6_flowlabel_opt_get(sk, &freq, flags);
1420                 if (val < 0)
1421                         return val;
1422
1423                 if (put_user(len, optlen))
1424                         return -EFAULT;
1425                 if (copy_to_user(optval, &freq, len))
1426                         return -EFAULT;
1427
1428                 return 0;
1429         }
1430
1431         case IPV6_ADDR_PREFERENCES:
1432                 val = 0;
1433
1434                 if (np->srcprefs & IPV6_PREFER_SRC_TMP)
1435                         val |= IPV6_PREFER_SRC_TMP;
1436                 else if (np->srcprefs & IPV6_PREFER_SRC_PUBLIC)
1437                         val |= IPV6_PREFER_SRC_PUBLIC;
1438                 else {
1439                         /* XXX: should we return system default? */
1440                         val |= IPV6_PREFER_SRC_PUBTMP_DEFAULT;
1441                 }
1442
1443                 if (np->srcprefs & IPV6_PREFER_SRC_COA)
1444                         val |= IPV6_PREFER_SRC_COA;
1445                 else
1446                         val |= IPV6_PREFER_SRC_HOME;
1447                 break;
1448
1449         case IPV6_MINHOPCOUNT:
1450                 val = np->min_hopcount;
1451                 break;
1452
1453         case IPV6_DONTFRAG:
1454                 val = np->dontfrag;
1455                 break;
1456
1457         case IPV6_AUTOFLOWLABEL:
1458                 val = ip6_autoflowlabel(sock_net(sk), np);
1459                 break;
1460
1461         case IPV6_RECVFRAGSIZE:
1462                 val = np->rxopt.bits.recvfragsize;
1463                 break;
1464
1465         case IPV6_ROUTER_ALERT_ISOLATE:
1466                 val = np->rtalert_isolate;
1467                 break;
1468
1469         case IPV6_RECVERR_RFC4884:
1470                 val = np->recverr_rfc4884;
1471                 break;
1472
1473         default:
1474                 return -ENOPROTOOPT;
1475         }
1476         len = min_t(unsigned int, sizeof(int), len);
1477         if (put_user(len, optlen))
1478                 return -EFAULT;
1479         if (copy_to_user(optval, &val, len))
1480                 return -EFAULT;
1481         return 0;
1482 }
1483
1484 int ipv6_getsockopt(struct sock *sk, int level, int optname,
1485                     char __user *optval, int __user *optlen)
1486 {
1487         int err;
1488
1489         if (level == SOL_IP && sk->sk_type != SOCK_RAW)
1490                 return udp_prot.getsockopt(sk, level, optname, optval, optlen);
1491
1492         if (level != SOL_IPV6)
1493                 return -ENOPROTOOPT;
1494
1495         err = do_ipv6_getsockopt(sk, level, optname, optval, optlen, 0);
1496 #ifdef CONFIG_NETFILTER
1497         /* we need to exclude all possible ENOPROTOOPTs except default case */
1498         if (err == -ENOPROTOOPT && optname != IPV6_2292PKTOPTIONS) {
1499                 int len;
1500
1501                 if (get_user(len, optlen))
1502                         return -EFAULT;
1503
1504                 err = nf_getsockopt(sk, PF_INET6, optname, optval, &len);
1505                 if (err >= 0)
1506                         err = put_user(len, optlen);
1507         }
1508 #endif
1509         return err;
1510 }
1511 EXPORT_SYMBOL(ipv6_getsockopt);