linux/net/ipv6/datagram.c
<<
>>
Prefs
   1/*
   2 *      common UDP/RAW code
   3 *      Linux INET6 implementation
   4 *
   5 *      Authors:
   6 *      Pedro Roque             <roque@di.fc.ul.pt>
   7 *
   8 *      This program is free software; you can redistribute it and/or
   9 *      modify it under the terms of the GNU General Public License
  10 *      as published by the Free Software Foundation; either version
  11 *      2 of the License, or (at your option) any later version.
  12 */
  13
  14#include <linux/capability.h>
  15#include <linux/errno.h>
  16#include <linux/types.h>
  17#include <linux/kernel.h>
  18#include <linux/interrupt.h>
  19#include <linux/socket.h>
  20#include <linux/sockios.h>
  21#include <linux/in6.h>
  22#include <linux/ipv6.h>
  23#include <linux/route.h>
  24
  25#include <net/ipv6.h>
  26#include <net/ndisc.h>
  27#include <net/addrconf.h>
  28#include <net/transp_v6.h>
  29#include <net/ip6_route.h>
  30#include <net/tcp_states.h>
  31
  32#include <linux/errqueue.h>
  33#include <asm/uaccess.h>
  34
  35int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
  36{
  37        struct sockaddr_in6     *usin = (struct sockaddr_in6 *) uaddr;
  38        struct inet_sock        *inet = inet_sk(sk);
  39        struct ipv6_pinfo       *np = inet6_sk(sk);
  40        struct in6_addr         *daddr, *final_p = NULL, final;
  41        struct dst_entry        *dst;
  42        struct flowi            fl;
  43        struct ip6_flowlabel    *flowlabel = NULL;
  44        int                     addr_type;
  45        int                     err;
  46
  47        if (usin->sin6_family == AF_INET) {
  48                if (__ipv6_only_sock(sk))
  49                        return -EAFNOSUPPORT;
  50                err = ip4_datagram_connect(sk, uaddr, addr_len);
  51                goto ipv4_connected;
  52        }
  53
  54        if (addr_len < SIN6_LEN_RFC2133)
  55                return -EINVAL;
  56
  57        if (usin->sin6_family != AF_INET6)
  58                return -EAFNOSUPPORT;
  59
  60        memset(&fl, 0, sizeof(fl));
  61        if (np->sndflow) {
  62                fl.fl6_flowlabel = usin->sin6_flowinfo&IPV6_FLOWINFO_MASK;
  63                if (fl.fl6_flowlabel&IPV6_FLOWLABEL_MASK) {
  64                        flowlabel = fl6_sock_lookup(sk, fl.fl6_flowlabel);
  65                        if (flowlabel == NULL)
  66                                return -EINVAL;
  67                        ipv6_addr_copy(&usin->sin6_addr, &flowlabel->dst);
  68                }
  69        }
  70
  71        addr_type = ipv6_addr_type(&usin->sin6_addr);
  72
  73        if (addr_type == IPV6_ADDR_ANY) {
  74                /*
  75                 *      connect to self
  76                 */
  77                usin->sin6_addr.s6_addr[15] = 0x01;
  78        }
  79
  80        daddr = &usin->sin6_addr;
  81
  82        if (addr_type == IPV6_ADDR_MAPPED) {
  83                struct sockaddr_in sin;
  84
  85                if (__ipv6_only_sock(sk)) {
  86                        err = -ENETUNREACH;
  87                        goto out;
  88                }
  89                sin.sin_family = AF_INET;
  90                sin.sin_addr.s_addr = daddr->s6_addr32[3];
  91                sin.sin_port = usin->sin6_port;
  92
  93                err = ip4_datagram_connect(sk,
  94                                           (struct sockaddr*) &sin,
  95                                           sizeof(sin));
  96
  97ipv4_connected:
  98                if (err)
  99                        goto out;
 100
 101                ipv6_addr_set(&np->daddr, 0, 0, htonl(0x0000ffff), inet->daddr);
 102
 103                if (ipv6_addr_any(&np->saddr)) {
 104                        ipv6_addr_set(&np->saddr, 0, 0, htonl(0x0000ffff),
 105                                      inet->saddr);
 106                }
 107
 108                if (ipv6_addr_any(&np->rcv_saddr)) {
 109                        ipv6_addr_set(&np->rcv_saddr, 0, 0, htonl(0x0000ffff),
 110                                      inet->rcv_saddr);
 111                }
 112                goto out;
 113        }
 114
 115        if (addr_type&IPV6_ADDR_LINKLOCAL) {
 116                if (addr_len >= sizeof(struct sockaddr_in6) &&
 117                    usin->sin6_scope_id) {
 118                        if (sk->sk_bound_dev_if &&
 119                            sk->sk_bound_dev_if != usin->sin6_scope_id) {
 120                                err = -EINVAL;
 121                                goto out;
 122                        }
 123                        sk->sk_bound_dev_if = usin->sin6_scope_id;
 124                }
 125
 126                if (!sk->sk_bound_dev_if && (addr_type & IPV6_ADDR_MULTICAST))
 127                        sk->sk_bound_dev_if = np->mcast_oif;
 128
 129                /* Connect to link-local address requires an interface */
 130                if (!sk->sk_bound_dev_if) {
 131                        err = -EINVAL;
 132                        goto out;
 133                }
 134        }
 135
 136        ipv6_addr_copy(&np->daddr, daddr);
 137        np->flow_label = fl.fl6_flowlabel;
 138
 139        inet->dport = usin->sin6_port;
 140
 141        /*
 142         *      Check for a route to destination an obtain the
 143         *      destination cache for it.
 144         */
 145
 146        fl.proto = sk->sk_protocol;
 147        ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
 148        ipv6_addr_copy(&fl.fl6_src, &np->saddr);
 149        fl.oif = sk->sk_bound_dev_if;
 150        fl.fl_ip_dport = inet->dport;
 151        fl.fl_ip_sport = inet->sport;
 152
 153        if (!fl.oif && (addr_type&IPV6_ADDR_MULTICAST))
 154                fl.oif = np->mcast_oif;
 155
 156        security_sk_classify_flow(sk, &fl);
 157
 158        if (flowlabel) {
 159                if (flowlabel->opt && flowlabel->opt->srcrt) {
 160                        struct rt0_hdr *rt0 = (struct rt0_hdr *) flowlabel->opt->srcrt;
 161                        ipv6_addr_copy(&final, &fl.fl6_dst);
 162                        ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
 163                        final_p = &final;
 164                }
 165        } else if (np->opt && np->opt->srcrt) {
 166                struct rt0_hdr *rt0 = (struct rt0_hdr *)np->opt->srcrt;
 167                ipv6_addr_copy(&final, &fl.fl6_dst);
 168                ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
 169                final_p = &final;
 170        }
 171
 172        err = ip6_dst_lookup(sk, &dst, &fl);
 173        if (err)
 174                goto out;
 175        if (final_p)
 176                ipv6_addr_copy(&fl.fl6_dst, final_p);
 177
 178        err = __xfrm_lookup(sock_net(sk), &dst, &fl, sk, XFRM_LOOKUP_WAIT);
 179        if (err < 0) {
 180                if (err == -EREMOTE)
 181                        err = ip6_dst_blackhole(sk, &dst, &fl);
 182                if (err < 0)
 183                        goto out;
 184        }
 185
 186        /* source address lookup done in ip6_dst_lookup */
 187
 188        if (ipv6_addr_any(&np->saddr))
 189                ipv6_addr_copy(&np->saddr, &fl.fl6_src);
 190
 191        if (ipv6_addr_any(&np->rcv_saddr)) {
 192                ipv6_addr_copy(&np->rcv_saddr, &fl.fl6_src);
 193                inet->rcv_saddr = LOOPBACK4_IPV6;
 194        }
 195
 196        ip6_dst_store(sk, dst,
 197                      ipv6_addr_equal(&fl.fl6_dst, &np->daddr) ?
 198                      &np->daddr : NULL,
 199#ifdef CONFIG_IPV6_SUBTREES
 200                      ipv6_addr_equal(&fl.fl6_src, &np->saddr) ?
 201                      &np->saddr :
 202#endif
 203                      NULL);
 204
 205        sk->sk_state = TCP_ESTABLISHED;
 206out:
 207        fl6_sock_release(flowlabel);
 208        return err;
 209}
 210
 211void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
 212                     __be16 port, u32 info, u8 *payload)
 213{
 214        struct ipv6_pinfo *np  = inet6_sk(sk);
 215        struct icmp6hdr *icmph = icmp6_hdr(skb);
 216        struct sock_exterr_skb *serr;
 217
 218        if (!np->recverr)
 219                return;
 220
 221        skb = skb_clone(skb, GFP_ATOMIC);
 222        if (!skb)
 223                return;
 224
 225        serr = SKB_EXT_ERR(skb);
 226        serr->ee.ee_errno = err;
 227        serr->ee.ee_origin = SO_EE_ORIGIN_ICMP6;
 228        serr->ee.ee_type = icmph->icmp6_type;
 229        serr->ee.ee_code = icmph->icmp6_code;
 230        serr->ee.ee_pad = 0;
 231        serr->ee.ee_info = info;
 232        serr->ee.ee_data = 0;
 233        serr->addr_offset = (u8 *)&(((struct ipv6hdr *)(icmph + 1))->daddr) -
 234                                  skb_network_header(skb);
 235        serr->port = port;
 236
 237        __skb_pull(skb, payload - skb->data);
 238        skb_reset_transport_header(skb);
 239
 240        if (sock_queue_err_skb(sk, skb))
 241                kfree_skb(skb);
 242}
 243
 244void ipv6_local_error(struct sock *sk, int err, struct flowi *fl, u32 info)
 245{
 246        struct ipv6_pinfo *np = inet6_sk(sk);
 247        struct sock_exterr_skb *serr;
 248        struct ipv6hdr *iph;
 249        struct sk_buff *skb;
 250
 251        if (!np->recverr)
 252                return;
 253
 254        skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
 255        if (!skb)
 256                return;
 257
 258        skb_put(skb, sizeof(struct ipv6hdr));
 259        skb_reset_network_header(skb);
 260        iph = ipv6_hdr(skb);
 261        ipv6_addr_copy(&iph->daddr, &fl->fl6_dst);
 262
 263        serr = SKB_EXT_ERR(skb);
 264        serr->ee.ee_errno = err;
 265        serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
 266        serr->ee.ee_type = 0;
 267        serr->ee.ee_code = 0;
 268        serr->ee.ee_pad = 0;
 269        serr->ee.ee_info = info;
 270        serr->ee.ee_data = 0;
 271        serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
 272        serr->port = fl->fl_ip_dport;
 273
 274        __skb_pull(skb, skb_tail_pointer(skb) - skb->data);
 275        skb_reset_transport_header(skb);
 276
 277        if (sock_queue_err_skb(sk, skb))
 278                kfree_skb(skb);
 279}
 280
 281/*
 282 *      Handle MSG_ERRQUEUE
 283 */
 284int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len)
 285{
 286        struct ipv6_pinfo *np = inet6_sk(sk);
 287        struct sock_exterr_skb *serr;
 288        struct sk_buff *skb, *skb2;
 289        struct sockaddr_in6 *sin;
 290        struct {
 291                struct sock_extended_err ee;
 292                struct sockaddr_in6      offender;
 293        } errhdr;
 294        int err;
 295        int copied;
 296
 297        err = -EAGAIN;
 298        skb = skb_dequeue(&sk->sk_error_queue);
 299        if (skb == NULL)
 300                goto out;
 301
 302        copied = skb->len;
 303        if (copied > len) {
 304                msg->msg_flags |= MSG_TRUNC;
 305                copied = len;
 306        }
 307        err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
 308        if (err)
 309                goto out_free_skb;
 310
 311        sock_recv_timestamp(msg, sk, skb);
 312
 313        serr = SKB_EXT_ERR(skb);
 314
 315        sin = (struct sockaddr_in6 *)msg->msg_name;
 316        if (sin) {
 317                const unsigned char *nh = skb_network_header(skb);
 318                sin->sin6_family = AF_INET6;
 319                sin->sin6_flowinfo = 0;
 320                sin->sin6_port = serr->port;
 321                sin->sin6_scope_id = 0;
 322                if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6) {
 323                        ipv6_addr_copy(&sin->sin6_addr,
 324                                  (struct in6_addr *)(nh + serr->addr_offset));
 325                        if (np->sndflow)
 326                                sin->sin6_flowinfo =
 327                                        (*(__be32 *)(nh + serr->addr_offset - 24) &
 328                                         IPV6_FLOWINFO_MASK);
 329                        if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
 330                                sin->sin6_scope_id = IP6CB(skb)->iif;
 331                } else {
 332                        ipv6_addr_set(&sin->sin6_addr, 0, 0,
 333                                      htonl(0xffff),
 334                                      *(__be32 *)(nh + serr->addr_offset));
 335                }
 336        }
 337
 338        memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
 339        sin = &errhdr.offender;
 340        sin->sin6_family = AF_UNSPEC;
 341        if (serr->ee.ee_origin != SO_EE_ORIGIN_LOCAL) {
 342                sin->sin6_family = AF_INET6;
 343                sin->sin6_flowinfo = 0;
 344                sin->sin6_scope_id = 0;
 345                if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6) {
 346                        ipv6_addr_copy(&sin->sin6_addr, &ipv6_hdr(skb)->saddr);
 347                        if (np->rxopt.all)
 348                                datagram_recv_ctl(sk, msg, skb);
 349                        if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
 350                                sin->sin6_scope_id = IP6CB(skb)->iif;
 351                } else {
 352                        struct inet_sock *inet = inet_sk(sk);
 353
 354                        ipv6_addr_set(&sin->sin6_addr, 0, 0,
 355                                      htonl(0xffff), ip_hdr(skb)->saddr);
 356                        if (inet->cmsg_flags)
 357                                ip_cmsg_recv(msg, skb);
 358                }
 359        }
 360
 361        put_cmsg(msg, SOL_IPV6, IPV6_RECVERR, sizeof(errhdr), &errhdr);
 362
 363        /* Now we could try to dump offended packet options */
 364
 365        msg->msg_flags |= MSG_ERRQUEUE;
 366        err = copied;
 367
 368        /* Reset and regenerate socket error */
 369        spin_lock_bh(&sk->sk_error_queue.lock);
 370        sk->sk_err = 0;
 371        if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
 372                sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
 373                spin_unlock_bh(&sk->sk_error_queue.lock);
 374                sk->sk_error_report(sk);
 375        } else {
 376                spin_unlock_bh(&sk->sk_error_queue.lock);
 377        }
 378
 379out_free_skb:
 380        kfree_skb(skb);
 381out:
 382        return err;
 383}
 384
 385
 386
 387int datagram_recv_ctl(struct sock *sk, struct msghdr *msg, struct sk_buff *skb)
 388{
 389        struct ipv6_pinfo *np = inet6_sk(sk);
 390        struct inet6_skb_parm *opt = IP6CB(skb);
 391        unsigned char *nh = skb_network_header(skb);
 392
 393        if (np->rxopt.bits.rxinfo) {
 394                struct in6_pktinfo src_info;
 395
 396                src_info.ipi6_ifindex = opt->iif;
 397                ipv6_addr_copy(&src_info.ipi6_addr, &ipv6_hdr(skb)->daddr);
 398                put_cmsg(msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info);
 399        }
 400
 401        if (np->rxopt.bits.rxhlim) {
 402                int hlim = ipv6_hdr(skb)->hop_limit;
 403                put_cmsg(msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
 404        }
 405
 406        if (np->rxopt.bits.rxtclass) {
 407                int tclass = (ntohl(*(__be32 *)ipv6_hdr(skb)) >> 20) & 0xff;
 408                put_cmsg(msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
 409        }
 410
 411        if (np->rxopt.bits.rxflow && (*(__be32 *)nh & IPV6_FLOWINFO_MASK)) {
 412                __be32 flowinfo = *(__be32 *)nh & IPV6_FLOWINFO_MASK;
 413                put_cmsg(msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
 414        }
 415
 416        /* HbH is allowed only once */
 417        if (np->rxopt.bits.hopopts && opt->hop) {
 418                u8 *ptr = nh + opt->hop;
 419                put_cmsg(msg, SOL_IPV6, IPV6_HOPOPTS, (ptr[1]+1)<<3, ptr);
 420        }
 421
 422        if (opt->lastopt &&
 423            (np->rxopt.bits.dstopts || np->rxopt.bits.srcrt)) {
 424                /*
 425                 * Silly enough, but we need to reparse in order to
 426                 * report extension headers (except for HbH)
 427                 * in order.
 428                 *
 429                 * Also note that IPV6_RECVRTHDRDSTOPTS is NOT
 430                 * (and WILL NOT be) defined because
 431                 * IPV6_RECVDSTOPTS is more generic. --yoshfuji
 432                 */
 433                unsigned int off = sizeof(struct ipv6hdr);
 434                u8 nexthdr = ipv6_hdr(skb)->nexthdr;
 435
 436                while (off <= opt->lastopt) {
 437                        unsigned len;
 438                        u8 *ptr = nh + off;
 439
 440                        switch(nexthdr) {
 441                        case IPPROTO_DSTOPTS:
 442                                nexthdr = ptr[0];
 443                                len = (ptr[1] + 1) << 3;
 444                                if (np->rxopt.bits.dstopts)
 445                                        put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, len, ptr);
 446                                break;
 447                        case IPPROTO_ROUTING:
 448                                nexthdr = ptr[0];
 449                                len = (ptr[1] + 1) << 3;
 450                                if (np->rxopt.bits.srcrt)
 451                                        put_cmsg(msg, SOL_IPV6, IPV6_RTHDR, len, ptr);
 452                                break;
 453                        case IPPROTO_AH:
 454                                nexthdr = ptr[0];
 455                                len = (ptr[1] + 2) << 2;
 456                                break;
 457                        default:
 458                                nexthdr = ptr[0];
 459                                len = (ptr[1] + 1) << 3;
 460                                break;
 461                        }
 462
 463                        off += len;
 464                }
 465        }
 466
 467        /* socket options in old style */
 468        if (np->rxopt.bits.rxoinfo) {
 469                struct in6_pktinfo src_info;
 470
 471                src_info.ipi6_ifindex = opt->iif;
 472                ipv6_addr_copy(&src_info.ipi6_addr, &ipv6_hdr(skb)->daddr);
 473                put_cmsg(msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
 474        }
 475        if (np->rxopt.bits.rxohlim) {
 476                int hlim = ipv6_hdr(skb)->hop_limit;
 477                put_cmsg(msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
 478        }
 479        if (np->rxopt.bits.ohopopts && opt->hop) {
 480                u8 *ptr = nh + opt->hop;
 481                put_cmsg(msg, SOL_IPV6, IPV6_2292HOPOPTS, (ptr[1]+1)<<3, ptr);
 482        }
 483        if (np->rxopt.bits.odstopts && opt->dst0) {
 484                u8 *ptr = nh + opt->dst0;
 485                put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
 486        }
 487        if (np->rxopt.bits.osrcrt && opt->srcrt) {
 488                struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(nh + opt->srcrt);
 489                put_cmsg(msg, SOL_IPV6, IPV6_2292RTHDR, (rthdr->hdrlen+1) << 3, rthdr);
 490        }
 491        if (np->rxopt.bits.odstopts && opt->dst1) {
 492                u8 *ptr = nh + opt->dst1;
 493                put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
 494        }
 495        return 0;
 496}
 497
 498int datagram_send_ctl(struct net *net,
 499                      struct msghdr *msg, struct flowi *fl,
 500                      struct ipv6_txoptions *opt,
 501                      int *hlimit, int *tclass)
 502{
 503        struct in6_pktinfo *src_info;
 504        struct cmsghdr *cmsg;
 505        struct ipv6_rt_hdr *rthdr;
 506        struct ipv6_opt_hdr *hdr;
 507        int len;
 508        int err = 0;
 509
 510        for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
 511                int addr_type;
 512
 513                if (!CMSG_OK(msg, cmsg)) {
 514                        err = -EINVAL;
 515                        goto exit_f;
 516                }
 517
 518                if (cmsg->cmsg_level != SOL_IPV6)
 519                        continue;
 520
 521                switch (cmsg->cmsg_type) {
 522                case IPV6_PKTINFO:
 523                case IPV6_2292PKTINFO:
 524                    {
 525                        struct net_device *dev = NULL;
 526
 527                        if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct in6_pktinfo))) {
 528                                err = -EINVAL;
 529                                goto exit_f;
 530                        }
 531
 532                        src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
 533
 534                        if (src_info->ipi6_ifindex) {
 535                                if (fl->oif && src_info->ipi6_ifindex != fl->oif)
 536                                        return -EINVAL;
 537                                fl->oif = src_info->ipi6_ifindex;
 538                        }
 539
 540                        addr_type = __ipv6_addr_type(&src_info->ipi6_addr);
 541
 542                        if (fl->oif) {
 543                                dev = dev_get_by_index(net, fl->oif);
 544                                if (!dev)
 545                                        return -ENODEV;
 546                        } else if (addr_type & IPV6_ADDR_LINKLOCAL)
 547                                return -EINVAL;
 548
 549                        if (addr_type != IPV6_ADDR_ANY) {
 550                                int strict = __ipv6_addr_src_scope(addr_type) <= IPV6_ADDR_SCOPE_LINKLOCAL;
 551                                if (!ipv6_chk_addr(net, &src_info->ipi6_addr,
 552                                                   strict ? dev : NULL, 0))
 553                                        err = -EINVAL;
 554                                else
 555                                        ipv6_addr_copy(&fl->fl6_src, &src_info->ipi6_addr);
 556                        }
 557
 558                        if (dev)
 559                                dev_put(dev);
 560
 561                        if (err)
 562                                goto exit_f;
 563
 564                        break;
 565                    }
 566
 567                case IPV6_FLOWINFO:
 568                        if (cmsg->cmsg_len < CMSG_LEN(4)) {
 569                                err = -EINVAL;
 570                                goto exit_f;
 571                        }
 572
 573                        if (fl->fl6_flowlabel&IPV6_FLOWINFO_MASK) {
 574                                if ((fl->fl6_flowlabel^*(__be32 *)CMSG_DATA(cmsg))&~IPV6_FLOWINFO_MASK) {
 575                                        err = -EINVAL;
 576                                        goto exit_f;
 577                                }
 578                        }
 579                        fl->fl6_flowlabel = IPV6_FLOWINFO_MASK & *(__be32 *)CMSG_DATA(cmsg);
 580                        break;
 581
 582                case IPV6_2292HOPOPTS:
 583                case IPV6_HOPOPTS:
 584                        if (opt->hopopt || cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
 585                                err = -EINVAL;
 586                                goto exit_f;
 587                        }
 588
 589                        hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
 590                        len = ((hdr->hdrlen + 1) << 3);
 591                        if (cmsg->cmsg_len < CMSG_LEN(len)) {
 592                                err = -EINVAL;
 593                                goto exit_f;
 594                        }
 595                        if (!capable(CAP_NET_RAW)) {
 596                                err = -EPERM;
 597                                goto exit_f;
 598                        }
 599                        opt->opt_nflen += len;
 600                        opt->hopopt = hdr;
 601                        break;
 602
 603                case IPV6_2292DSTOPTS:
 604                        if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
 605                                err = -EINVAL;
 606                                goto exit_f;
 607                        }
 608
 609                        hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
 610                        len = ((hdr->hdrlen + 1) << 3);
 611                        if (cmsg->cmsg_len < CMSG_LEN(len)) {
 612                                err = -EINVAL;
 613                                goto exit_f;
 614                        }
 615                        if (!capable(CAP_NET_RAW)) {
 616                                err = -EPERM;
 617                                goto exit_f;
 618                        }
 619                        if (opt->dst1opt) {
 620                                err = -EINVAL;
 621                                goto exit_f;
 622                        }
 623                        opt->opt_flen += len;
 624                        opt->dst1opt = hdr;
 625                        break;
 626
 627                case IPV6_DSTOPTS:
 628                case IPV6_RTHDRDSTOPTS:
 629                        if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
 630                                err = -EINVAL;
 631                                goto exit_f;
 632                        }
 633
 634                        hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
 635                        len = ((hdr->hdrlen + 1) << 3);
 636                        if (cmsg->cmsg_len < CMSG_LEN(len)) {
 637                                err = -EINVAL;
 638                                goto exit_f;
 639                        }
 640                        if (!capable(CAP_NET_RAW)) {
 641                                err = -EPERM;
 642                                goto exit_f;
 643                        }
 644                        if (cmsg->cmsg_type == IPV6_DSTOPTS) {
 645                                opt->opt_flen += len;
 646                                opt->dst1opt = hdr;
 647                        } else {
 648                                opt->opt_nflen += len;
 649                                opt->dst0opt = hdr;
 650                        }
 651                        break;
 652
 653                case IPV6_2292RTHDR:
 654                case IPV6_RTHDR:
 655                        if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_rt_hdr))) {
 656                                err = -EINVAL;
 657                                goto exit_f;
 658                        }
 659
 660                        rthdr = (struct ipv6_rt_hdr *)CMSG_DATA(cmsg);
 661
 662                        switch (rthdr->type) {
 663#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
 664                        case IPV6_SRCRT_TYPE_2:
 665                                if (rthdr->hdrlen != 2 ||
 666                                    rthdr->segments_left != 1) {
 667                                        err = -EINVAL;
 668                                        goto exit_f;
 669                                }
 670                                break;
 671#endif
 672                        default:
 673                                err = -EINVAL;
 674                                goto exit_f;
 675                        }
 676
 677                        len = ((rthdr->hdrlen + 1) << 3);
 678
 679                        if (cmsg->cmsg_len < CMSG_LEN(len)) {
 680                                err = -EINVAL;
 681                                goto exit_f;
 682                        }
 683
 684                        /* segments left must also match */
 685                        if ((rthdr->hdrlen >> 1) != rthdr->segments_left) {
 686                                err = -EINVAL;
 687                                goto exit_f;
 688                        }
 689
 690                        opt->opt_nflen += len;
 691                        opt->srcrt = rthdr;
 692
 693                        if (cmsg->cmsg_type == IPV6_2292RTHDR && opt->dst1opt) {
 694                                int dsthdrlen = ((opt->dst1opt->hdrlen+1)<<3);
 695
 696                                opt->opt_nflen += dsthdrlen;
 697                                opt->dst0opt = opt->dst1opt;
 698                                opt->dst1opt = NULL;
 699                                opt->opt_flen -= dsthdrlen;
 700                        }
 701
 702                        break;
 703
 704                case IPV6_2292HOPLIMIT:
 705                case IPV6_HOPLIMIT:
 706                        if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
 707                                err = -EINVAL;
 708                                goto exit_f;
 709                        }
 710
 711                        *hlimit = *(int *)CMSG_DATA(cmsg);
 712                        if (*hlimit < -1 || *hlimit > 0xff) {
 713                                err = -EINVAL;
 714                                goto exit_f;
 715                        }
 716
 717                        break;
 718
 719                case IPV6_TCLASS:
 720                    {
 721                        int tc;
 722
 723                        err = -EINVAL;
 724                        if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
 725                                goto exit_f;
 726                        }
 727
 728                        tc = *(int *)CMSG_DATA(cmsg);
 729                        if (tc < -1 || tc > 0xff)
 730                                goto exit_f;
 731
 732                        err = 0;
 733                        *tclass = tc;
 734
 735                        break;
 736                    }
 737                default:
 738                        LIMIT_NETDEBUG(KERN_DEBUG "invalid cmsg type: %d\n",
 739                                       cmsg->cmsg_type);
 740                        err = -EINVAL;
 741                        goto exit_f;
 742                }
 743        }
 744
 745exit_f:
 746        return err;
 747}
 748