net/ipv6/datagram.c

   1 /*
   2  *      common UDP/RAW code
   3  *      Linux INET6 implementation
   4  *
   5  *      Authors:
   6  *      Pedro Roque             <roque@di.fc.ul.pt>
   7  *
   8  *      $Id: datagram.c,v 1.24 2002/02/01 22:01:04 davem Exp $
   9  *
  10  *      This program is free software; you can redistribute it and/or
  11  *      modify it under the terms of the GNU General Public License
  12  *      as published by the Free Software Foundation; either version
  13  *      2 of the License, or (at your option) any later version.
  14  */
  15
  16 #include <linux/capability.h>
  17 #include <linux/errno.h>
  18 #include <linux/types.h>
  19 #include <linux/kernel.h>
  20 #include <linux/sched.h>
  21 #include <linux/interrupt.h>
  22 #include <linux/socket.h>
  23 #include <linux/sockios.h>
  24 #include <linux/in6.h>
  25 #include <linux/ipv6.h>
  26 #include <linux/route.h>
  27
  28 #include <net/ipv6.h>
  29 #include <net/ndisc.h>
  30 #include <net/addrconf.h>
  31 #include <net/transp_v6.h>
  32 #include <net/ip6_route.h>
  33 #include <net/tcp_states.h>
  34
  35 #include <linux/errqueue.h>
  36 #include <asm/uaccess.h>
  37
  38 int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
  39 {
  40         struct sockaddr_in6     *usin = (struct sockaddr_in6 *) uaddr;
  41         struct inet_sock        *inet = inet_sk(sk);
  42         struct ipv6_pinfo       *np = inet6_sk(sk);
  43         struct in6_addr         *daddr, *final_p = NULL, final;
  44         struct dst_entry        *dst;
  45         struct flowi            fl;
  46         struct ip6_flowlabel    *flowlabel = NULL;
  47         int                     addr_type;
  48         int                     err;
  49
  50         if (usin->sin6_family == AF_INET) {
  51                 if (__ipv6_only_sock(sk))
  52                         return -EAFNOSUPPORT;
  53                 err = ip4_datagram_connect(sk, uaddr, addr_len);
  54                 goto ipv4_connected;
  55         }
  56
  57         if (addr_len < SIN6_LEN_RFC2133)
  58                 return -EINVAL;
  59
  60         if (usin->sin6_family != AF_INET6)
  61                 return -EAFNOSUPPORT;
  62
  63         memset(&fl, 0, sizeof(fl));
  64         if (np->sndflow) {
  65                 fl.fl6_flowlabel = usin->sin6_flowinfo&IPV6_FLOWINFO_MASK;
  66                 if (fl.fl6_flowlabel&IPV6_FLOWLABEL_MASK) {
  67                         flowlabel = fl6_sock_lookup(sk, fl.fl6_flowlabel);
  68                         if (flowlabel == NULL)
  69                                 return -EINVAL;
  70                         ipv6_addr_copy(&usin->sin6_addr, &flowlabel->dst);
  71                 }
  72         }
  73
  74         addr_type = ipv6_addr_type(&usin->sin6_addr);
  75
  76         if (addr_type == IPV6_ADDR_ANY) {
  77                 /*
  78                  *      connect to self
  79                  */
  80                 usin->sin6_addr.s6_addr[15] = 0x01;
  81         }
  82
  83         daddr = &usin->sin6_addr;
  84
  85         if (addr_type == IPV6_ADDR_MAPPED) {
  86                 struct sockaddr_in sin;
  87
  88                 if (__ipv6_only_sock(sk)) {
  89                         err = -ENETUNREACH;
  90                         goto out;
  91                 }
  92                 sin.sin_family = AF_INET;
  93                 sin.sin_addr.s_addr = daddr->s6_addr32[3];
  94                 sin.sin_port = usin->sin6_port;
  95
  96                 err = ip4_datagram_connect(sk,
  97                                            (struct sockaddr*) &sin,
  98                                            sizeof(sin));
  99
 100 ipv4_connected:
 101                 if (err)
 102                         goto out;
 103
 104                 ipv6_addr_set(&np->daddr, 0, 0, htonl(0x0000ffff), inet->daddr);
 105
 106                 if (ipv6_addr_any(&np->saddr)) {
 107                         ipv6_addr_set(&np->saddr, 0, 0, htonl(0x0000ffff),
 108                                       inet->saddr);
 109                 }
 110
 111                 if (ipv6_addr_any(&np->rcv_saddr)) {
 112                         ipv6_addr_set(&np->rcv_saddr, 0, 0, htonl(0x0000ffff),
 113                                       inet->rcv_saddr);
 114                 }
 115                 goto out;
 116         }
 117
 118         if (addr_type&IPV6_ADDR_LINKLOCAL) {
 119                 if (addr_len >= sizeof(struct sockaddr_in6) &&
 120                     usin->sin6_scope_id) {
 121                         if (sk->sk_bound_dev_if &&
 122                             sk->sk_bound_dev_if != usin->sin6_scope_id) {
 123                                 err = -EINVAL;
 124                                 goto out;
 125                         }
 126                         sk->sk_bound_dev_if = usin->sin6_scope_id;
 127                         if (!sk->sk_bound_dev_if &&
 128                             (addr_type & IPV6_ADDR_MULTICAST))
 129                                 fl.oif = np->mcast_oif;
 130                 }
 131
 132                 /* Connect to link-local address requires an interface */
 133                 if (!sk->sk_bound_dev_if) {
 134                         err = -EINVAL;
 135                         goto out;
 136                 }
 137         }
 138
 139         ipv6_addr_copy(&np->daddr, daddr);
 140         np->flow_label = fl.fl6_flowlabel;
 141
 142         inet->dport = usin->sin6_port;
 143
 144         /*
 145          *      Check for a route to destination an obtain the
 146          *      destination cache for it.
 147          */
 148
 149         fl.proto = sk->sk_protocol;
 150         ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
 151         ipv6_addr_copy(&fl.fl6_src, &np->saddr);
 152         fl.oif = sk->sk_bound_dev_if;
 153         fl.fl_ip_dport = inet->dport;
 154         fl.fl_ip_sport = inet->sport;
 155
 156         if (!fl.oif && (addr_type&IPV6_ADDR_MULTICAST))
 157                 fl.oif = np->mcast_oif;
 158
 159         if (flowlabel) {
 160                 if (flowlabel->opt && flowlabel->opt->srcrt) {
 161                         struct rt0_hdr *rt0 = (struct rt0_hdr *) flowlabel->opt->srcrt;
 162                         ipv6_addr_copy(&final, &fl.fl6_dst);
 163                         ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
 164                         final_p = &final;
 165                 }
 166         } else if (np->opt && np->opt->srcrt) {
 167                 struct rt0_hdr *rt0 = (struct rt0_hdr *)np->opt->srcrt;
 168                 ipv6_addr_copy(&final, &fl.fl6_dst);
 169                 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
 170                 final_p = &final;
 171         }
 172
 173         err = ip6_dst_lookup(sk, &dst, &fl);
 174         if (err)
 175                 goto out;
 176         if (final_p)
 177                 ipv6_addr_copy(&fl.fl6_dst, final_p);
 178
 179         if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0)
 180                 goto out;
 181
 182         /* source address lookup done in ip6_dst_lookup */
 183
 184         if (ipv6_addr_any(&np->saddr))
 185                 ipv6_addr_copy(&np->saddr, &fl.fl6_src);
 186
 187         if (ipv6_addr_any(&np->rcv_saddr)) {
 188                 ipv6_addr_copy(&np->rcv_saddr, &fl.fl6_src);
 189                 inet->rcv_saddr = LOOPBACK4_IPV6;
 190         }
 191
 192         ip6_dst_store(sk, dst,
 193                       ipv6_addr_equal(&fl.fl6_dst, &np->daddr) ?
 194                       &np->daddr : NULL);
 195
 196         sk->sk_state = TCP_ESTABLISHED;
 197 out:
 198         fl6_sock_release(flowlabel);
 199         return err;
 200 }
 201
 202 void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
 203                      u16 port, u32 info, u8 *payload)
 204 {
 205         struct ipv6_pinfo *np  = inet6_sk(sk);
 206         struct icmp6hdr *icmph = (struct icmp6hdr *)skb->h.raw;
 207         struct sock_exterr_skb *serr;
 208
 209         if (!np->recverr)
 210                 return;
 211
 212         skb = skb_clone(skb, GFP_ATOMIC);
 213         if (!skb)
 214                 return;
 215
 216         serr = SKB_EXT_ERR(skb);
 217         serr->ee.ee_errno = err;
 218         serr->ee.ee_origin = SO_EE_ORIGIN_ICMP6;
 219         serr->ee.ee_type = icmph->icmp6_type;
 220         serr->ee.ee_code = icmph->icmp6_code;
 221         serr->ee.ee_pad = 0;
 222         serr->ee.ee_info = info;
 223         serr->ee.ee_data = 0;
 224         serr->addr_offset = (u8*)&(((struct ipv6hdr*)(icmph+1))->daddr) - skb->nh.raw;
 225         serr->port = port;
 226
 227         skb->h.raw = payload;
 228         __skb_pull(skb, payload - skb->data);
 229
 230         if (sock_queue_err_skb(sk, skb))
 231                 kfree_skb(skb);
 232 }
 233
 234 void ipv6_local_error(struct sock *sk, int err, struct flowi *fl, u32 info)
 235 {
 236         struct ipv6_pinfo *np = inet6_sk(sk);
 237         struct sock_exterr_skb *serr;
 238         struct ipv6hdr *iph;
 239         struct sk_buff *skb;
 240
 241         if (!np->recverr)
 242                 return;
 243
 244         skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
 245         if (!skb)
 246                 return;
 247
 248         iph = (struct ipv6hdr*)skb_put(skb, sizeof(struct ipv6hdr));
 249         skb->nh.ipv6h = iph;
 250         ipv6_addr_copy(&iph->daddr, &fl->fl6_dst);
 251
 252         serr = SKB_EXT_ERR(skb);
 253         serr->ee.ee_errno = err;
 254         serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
 255         serr->ee.ee_type = 0;
 256         serr->ee.ee_code = 0;
 257         serr->ee.ee_pad = 0;
 258         serr->ee.ee_info = info;
 259         serr->ee.ee_data = 0;
 260         serr->addr_offset = (u8*)&iph->daddr - skb->nh.raw;
 261         serr->port = fl->fl_ip_dport;
 262
 263         skb->h.raw = skb->tail;
 264         __skb_pull(skb, skb->tail - skb->data);
 265
 266         if (sock_queue_err_skb(sk, skb))
 267                 kfree_skb(skb);
 268 }
 269
 270 /*
 271  *      Handle MSG_ERRQUEUE
 272  */
 273 int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len)
 274 {
 275         struct ipv6_pinfo *np = inet6_sk(sk);
 276         struct sock_exterr_skb *serr;
 277         struct sk_buff *skb, *skb2;
 278         struct sockaddr_in6 *sin;
 279         struct {
 280                 struct sock_extended_err ee;
 281                 struct sockaddr_in6      offender;
 282         } errhdr;
 283         int err;
 284         int copied;
 285
 286         err = -EAGAIN;
 287         skb = skb_dequeue(&sk->sk_error_queue);
 288         if (skb == NULL)
 289                 goto out;
 290
 291         copied = skb->len;
 292         if (copied > len) {
 293                 msg->msg_flags |= MSG_TRUNC;
 294                 copied = len;
 295         }
 296         err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
 297         if (err)
 298                 goto out_free_skb;
 299
 300         sock_recv_timestamp(msg, sk, skb);
 301
 302         serr = SKB_EXT_ERR(skb);
 303
 304         sin = (struct sockaddr_in6 *)msg->msg_name;
 305         if (sin) {
 306                 sin->sin6_family = AF_INET6;
 307                 sin->sin6_flowinfo = 0;
 308                 sin->sin6_port = serr->port;
 309                 sin->sin6_scope_id = 0;
 310                 if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6) {
 311                         ipv6_addr_copy(&sin->sin6_addr,
 312                           (struct in6_addr *)(skb->nh.raw + serr->addr_offset));
 313                         if (np->sndflow)
 314                                 sin->sin6_flowinfo = *(u32*)(skb->nh.raw + serr->addr_offset - 24) & IPV6_FLOWINFO_MASK;
 315                         if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
 316                                 sin->sin6_scope_id = IP6CB(skb)->iif;
 317                 } else {
 318                         ipv6_addr_set(&sin->sin6_addr, 0, 0,
 319                                       htonl(0xffff),
 320                                       *(u32*)(skb->nh.raw + serr->addr_offset));
 321                 }
 322         }
 323
 324         memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
 325         sin = &errhdr.offender;
 326         sin->sin6_family = AF_UNSPEC;
 327         if (serr->ee.ee_origin != SO_EE_ORIGIN_LOCAL) {
 328                 sin->sin6_family = AF_INET6;
 329                 sin->sin6_flowinfo = 0;
 330                 sin->sin6_scope_id = 0;
 331                 if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6) {
 332                         ipv6_addr_copy(&sin->sin6_addr, &skb->nh.ipv6h->saddr);
 333                         if (np->rxopt.all)
 334                                 datagram_recv_ctl(sk, msg, skb);
 335                         if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
 336                                 sin->sin6_scope_id = IP6CB(skb)->iif;
 337                 } else {
 338                         struct inet_sock *inet = inet_sk(sk);
 339
 340                         ipv6_addr_set(&sin->sin6_addr, 0, 0,
 341                                       htonl(0xffff),
 342                                       skb->nh.iph->saddr);
 343                         if (inet->cmsg_flags)
 344                                 ip_cmsg_recv(msg, skb);
 345                 }
 346         }
 347
 348         put_cmsg(msg, SOL_IPV6, IPV6_RECVERR, sizeof(errhdr), &errhdr);
 349
 350         /* Now we could try to dump offended packet options */
 351
 352         msg->msg_flags |= MSG_ERRQUEUE;
 353         err = copied;
 354
 355         /* Reset and regenerate socket error */
 356         spin_lock_bh(&sk->sk_error_queue.lock);
 357         sk->sk_err = 0;
 358         if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
 359                 sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
 360                 spin_unlock_bh(&sk->sk_error_queue.lock);
 361                 sk->sk_error_report(sk);
 362         } else {
 363                 spin_unlock_bh(&sk->sk_error_queue.lock);
 364         }
 365
 366 out_free_skb:
 367         kfree_skb(skb);
 368 out:
 369         return err;
 370 }
 371
 372
 373
 374 int datagram_recv_ctl(struct sock *sk, struct msghdr *msg, struct sk_buff *skb)
 375 {
 376         struct ipv6_pinfo *np = inet6_sk(sk);
 377         struct inet6_skb_parm *opt = IP6CB(skb);
 378
 379         if (np->rxopt.bits.rxinfo) {
 380                 struct in6_pktinfo src_info;
 381
 382                 src_info.ipi6_ifindex = opt->iif;
 383                 ipv6_addr_copy(&src_info.ipi6_addr, &skb->nh.ipv6h->daddr);
 384                 put_cmsg(msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info);
 385         }
 386
 387         if (np->rxopt.bits.rxhlim) {
 388                 int hlim = skb->nh.ipv6h->hop_limit;
 389                 put_cmsg(msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
 390         }
 391
 392         if (np->rxopt.bits.rxtclass) {
 393                 int tclass = (ntohl(*(u32 *)skb->nh.ipv6h) >> 20) & 0xff;
 394                 put_cmsg(msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
 395         }
 396
 397         if (np->rxopt.bits.rxflow && (*(u32*)skb->nh.raw & IPV6_FLOWINFO_MASK)) {
 398                 u32 flowinfo = *(u32*)skb->nh.raw & IPV6_FLOWINFO_MASK;
 399                 put_cmsg(msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
 400         }
 401
 402         /* HbH is allowed only once */
 403         if (np->rxopt.bits.hopopts && opt->hop) {
 404                 u8 *ptr = skb->nh.raw + opt->hop;
 405                 put_cmsg(msg, SOL_IPV6, IPV6_HOPOPTS, (ptr[1]+1)<<3, ptr);
 406         }
 407
 408         if (opt->lastopt &&
 409             (np->rxopt.bits.dstopts || np->rxopt.bits.srcrt)) {
 410                 /*
 411                  * Silly enough, but we need to reparse in order to
 412                  * report extension headers (except for HbH)
 413                  * in order.
 414                  *
 415                  * Also note that IPV6_RECVRTHDRDSTOPTS is NOT
 416                  * (and WILL NOT be) defined because
 417                  * IPV6_RECVDSTOPTS is more generic. --yoshfuji
 418                  */
 419                 unsigned int off = sizeof(struct ipv6hdr);
 420                 u8 nexthdr = skb->nh.ipv6h->nexthdr;
 421
 422                 while (off <= opt->lastopt) {
 423                         unsigned len;
 424                         u8 *ptr = skb->nh.raw + off;
 425
 426                         switch(nexthdr) {
 427                         case IPPROTO_DSTOPTS:
 428                                 nexthdr = ptr[0];
 429                                 len = (ptr[1] + 1) << 3;
 430                                 if (np->rxopt.bits.dstopts)
 431                                         put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, len, ptr);
 432                                 break;
 433                         case IPPROTO_ROUTING:
 434                                 nexthdr = ptr[0];
 435                                 len = (ptr[1] + 1) << 3;
 436                                 if (np->rxopt.bits.srcrt)
 437                                         put_cmsg(msg, SOL_IPV6, IPV6_RTHDR, len, ptr);
 438                                 break;
 439                         case IPPROTO_AH:
 440                                 nexthdr = ptr[0];
 441                                 len = (ptr[1] + 2) << 2;
 442                                 break;
 443                         default:
 444                                 nexthdr = ptr[0];
 445                                 len = (ptr[1] + 1) << 3;
 446                                 break;
 447                         }
 448
 449                         off += len;
 450                 }
 451         }
 452
 453         /* socket options in old style */
 454         if (np->rxopt.bits.rxoinfo) {
 455                 struct in6_pktinfo src_info;
 456
 457                 src_info.ipi6_ifindex = opt->iif;
 458                 ipv6_addr_copy(&src_info.ipi6_addr, &skb->nh.ipv6h->daddr);
 459                 put_cmsg(msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
 460         }
 461         if (np->rxopt.bits.rxohlim) {
 462                 int hlim = skb->nh.ipv6h->hop_limit;
 463                 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
 464         }
 465         if (np->rxopt.bits.ohopopts && opt->hop) {
 466                 u8 *ptr = skb->nh.raw + opt->hop;
 467                 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPOPTS, (ptr[1]+1)<<3, ptr);
 468         }
 469         if (np->rxopt.bits.odstopts && opt->dst0) {
 470                 u8 *ptr = skb->nh.raw + opt->dst0;
 471                 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
 472         }
 473         if (np->rxopt.bits.osrcrt && opt->srcrt) {
 474                 struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(skb->nh.raw + opt->srcrt);
 475                 put_cmsg(msg, SOL_IPV6, IPV6_2292RTHDR, (rthdr->hdrlen+1) << 3, rthdr);
 476         }
 477         if (np->rxopt.bits.odstopts && opt->dst1) {
 478                 u8 *ptr = skb->nh.raw + opt->dst1;
 479                 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
 480         }
 481         return 0;
 482 }
 483
 484 int datagram_send_ctl(struct msghdr *msg, struct flowi *fl,
 485                       struct ipv6_txoptions *opt,
 486                       int *hlimit, int *tclass)
 487 {
 488         struct in6_pktinfo *src_info;
 489         struct cmsghdr *cmsg;
 490         struct ipv6_rt_hdr *rthdr;
 491         struct ipv6_opt_hdr *hdr;
 492         int len;
 493         int err = 0;
 494
 495         for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
 496                 int addr_type;
 497                 struct net_device *dev = NULL;
 498
 499                 if (!CMSG_OK(msg, cmsg)) {
 500                         err = -EINVAL;
 501                         goto exit_f;
 502                 }
 503
 504                 if (cmsg->cmsg_level != SOL_IPV6)
 505                         continue;
 506
 507                 switch (cmsg->cmsg_type) {
 508                 case IPV6_PKTINFO:
 509                 case IPV6_2292PKTINFO:
 510                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct in6_pktinfo))) {
 511                                 err = -EINVAL;
 512                                 goto exit_f;
 513                         }
 514
 515                         src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
 516
 517                         if (src_info->ipi6_ifindex) {
 518                                 if (fl->oif && src_info->ipi6_ifindex != fl->oif)
 519                                         return -EINVAL;
 520                                 fl->oif = src_info->ipi6_ifindex;
 521                         }
 522
 523                         addr_type = ipv6_addr_type(&src_info->ipi6_addr);
 524
 525                         if (addr_type == IPV6_ADDR_ANY)
 526                                 break;
 527
 528                         if (addr_type & IPV6_ADDR_LINKLOCAL) {
 529                                 if (!src_info->ipi6_ifindex)
 530                                         return -EINVAL;
 531                                 else {
 532                                         dev = dev_get_by_index(src_info->ipi6_ifindex);
 533                                         if (!dev)
 534                                                 return -ENODEV;
 535                                 }
 536                         }
 537                         if (!ipv6_chk_addr(&src_info->ipi6_addr, dev, 0)) {
 538                                 if (dev)
 539                                         dev_put(dev);
 540                                 err = -EINVAL;
 541                                 goto exit_f;
 542                         }
 543                         if (dev)
 544                                 dev_put(dev);
 545
 546                         ipv6_addr_copy(&fl->fl6_src, &src_info->ipi6_addr);
 547                         break;
 548
 549                 case IPV6_FLOWINFO:
 550                         if (cmsg->cmsg_len < CMSG_LEN(4)) {
 551                                 err = -EINVAL;
 552                                 goto exit_f;
 553                         }
 554
 555                         if (fl->fl6_flowlabel&IPV6_FLOWINFO_MASK) {
 556                                 if ((fl->fl6_flowlabel^*(u32 *)CMSG_DATA(cmsg))&~IPV6_FLOWINFO_MASK) {
 557                                         err = -EINVAL;
 558                                         goto exit_f;
 559                                 }
 560                         }
 561                         fl->fl6_flowlabel = IPV6_FLOWINFO_MASK & *(u32 *)CMSG_DATA(cmsg);
 562                         break;
 563
 564                 case IPV6_2292HOPOPTS:
 565                 case IPV6_HOPOPTS:
 566                         if (opt->hopopt || cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
 567                                 err = -EINVAL;
 568                                 goto exit_f;
 569                         }
 570
 571                         hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
 572                         len = ((hdr->hdrlen + 1) << 3);
 573                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
 574                                 err = -EINVAL;
 575                                 goto exit_f;
 576                         }
 577                         if (!capable(CAP_NET_RAW)) {
 578                                 err = -EPERM;
 579                                 goto exit_f;
 580                         }
 581                         opt->opt_nflen += len;
 582                         opt->hopopt = hdr;
 583                         break;
 584
 585                 case IPV6_2292DSTOPTS:
 586                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
 587                                 err = -EINVAL;
 588                                 goto exit_f;
 589                         }
 590
 591                         hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
 592                         len = ((hdr->hdrlen + 1) << 3);
 593                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
 594                                 err = -EINVAL;
 595                                 goto exit_f;
 596                         }
 597                         if (!capable(CAP_NET_RAW)) {
 598                                 err = -EPERM;
 599                                 goto exit_f;
 600                         }
 601                         if (opt->dst1opt) {
 602                                 err = -EINVAL;
 603                                 goto exit_f;
 604                         }
 605                         opt->opt_flen += len;
 606                         opt->dst1opt = hdr;
 607                         break;
 608
 609                 case IPV6_DSTOPTS:
 610                 case IPV6_RTHDRDSTOPTS:
 611                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
 612                                 err = -EINVAL;
 613                                 goto exit_f;
 614                         }
 615
 616                         hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
 617                         len = ((hdr->hdrlen + 1) << 3);
 618                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
 619                                 err = -EINVAL;
 620                                 goto exit_f;
 621                         }
 622                         if (!capable(CAP_NET_RAW)) {
 623                                 err = -EPERM;
 624                                 goto exit_f;
 625                         }
 626                         if (cmsg->cmsg_type == IPV6_DSTOPTS) {
 627                                 opt->opt_flen += len;
 628                                 opt->dst1opt = hdr;
 629                         } else {
 630                                 opt->opt_nflen += len;
 631                                 opt->dst0opt = hdr;
 632                         }
 633                         break;
 634
 635                 case IPV6_2292RTHDR:
 636                 case IPV6_RTHDR:
 637                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_rt_hdr))) {
 638                                 err = -EINVAL;
 639                                 goto exit_f;
 640                         }
 641
 642                         rthdr = (struct ipv6_rt_hdr *)CMSG_DATA(cmsg);
 643
 644                         /*
 645                          *      TYPE 0
 646                          */
 647                         if (rthdr->type) {
 648                                 err = -EINVAL;
 649                                 goto exit_f;
 650                         }
 651
 652                         len = ((rthdr->hdrlen + 1) << 3);
 653
 654                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
 655                                 err = -EINVAL;
 656                                 goto exit_f;
 657                         }
 658
 659                         /* segments left must also match */
 660                         if ((rthdr->hdrlen >> 1) != rthdr->segments_left) {
 661                                 err = -EINVAL;
 662                                 goto exit_f;
 663                         }
 664
 665                         opt->opt_nflen += len;
 666                         opt->srcrt = rthdr;
 667
 668                         if (cmsg->cmsg_type == IPV6_2292RTHDR && opt->dst1opt) {
 669                                 int dsthdrlen = ((opt->dst1opt->hdrlen+1)<<3);
 670
 671                                 opt->opt_nflen += dsthdrlen;
 672                                 opt->dst0opt = opt->dst1opt;
 673                                 opt->dst1opt = NULL;
 674                                 opt->opt_flen -= dsthdrlen;
 675                         }
 676
 677                         break;
 678
 679                 case IPV6_2292HOPLIMIT:
 680                 case IPV6_HOPLIMIT:
 681                         if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
 682                                 err = -EINVAL;
 683                                 goto exit_f;
 684                         }
 685
 686                         *hlimit = *(int *)CMSG_DATA(cmsg);
 687                         break;
 688
 689                 case IPV6_TCLASS:
 690                     {
 691                         int tc;
 692
 693                         err = -EINVAL;
 694                         if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
 695                                 goto exit_f;
 696                         }
 697
 698                         tc = *(int *)CMSG_DATA(cmsg);
 699                         if (tc < -1 || tc > 0xff)
 700                                 goto exit_f;
 701
 702                         err = 0;
 703                         *tclass = tc;
 704
 705                         break;
 706                     }
 707                 default:
 708                         LIMIT_NETDEBUG(KERN_DEBUG "invalid cmsg type: %d\n",
 709                                        cmsg->cmsg_type);
 710                         err = -EINVAL;
 711                         break;
 712                 };
 713         }
 714
 715 exit_f:
 716         return err;
 717 }