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/interrupt.h>
  21 #include <linux/socket.h>
  22 #include <linux/sockios.h>
  23 #include <linux/in6.h>
  24 #include <linux/ipv6.h>
  25 #include <linux/route.h>
  26
  27 #include <net/ipv6.h>
  28 #include <net/ndisc.h>
  29 #include <net/addrconf.h>
  30 #include <net/transp_v6.h>
  31 #include <net/ip6_route.h>
  32 #include <net/tcp_states.h>
  33
  34 #include <linux/errqueue.h>
  35 #include <asm/uaccess.h>
  36
  37 int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
  38 {
  39         struct sockaddr_in6     *usin = (struct sockaddr_in6 *) uaddr;
  40         struct inet_sock        *inet = inet_sk(sk);
  41         struct ipv6_pinfo       *np = inet6_sk(sk);
  42         struct in6_addr         *daddr, *final_p = NULL, final;
  43         struct dst_entry        *dst;
  44         struct flowi            fl;
  45         struct ip6_flowlabel    *flowlabel = NULL;
  46         int                     addr_type;
  47         int                     err;
  48
  49         if (usin->sin6_family == AF_INET) {
  50                 if (__ipv6_only_sock(sk))
  51                         return -EAFNOSUPPORT;
  52                 err = ip4_datagram_connect(sk, uaddr, addr_len);
  53                 goto ipv4_connected;
  54         }
  55
  56         if (addr_len < SIN6_LEN_RFC2133)
  57                 return -EINVAL;
  58
  59         if (usin->sin6_family != AF_INET6)
  60                 return -EAFNOSUPPORT;
  61
  62         memset(&fl, 0, sizeof(fl));
  63         if (np->sndflow) {
  64                 fl.fl6_flowlabel = usin->sin6_flowinfo&IPV6_FLOWINFO_MASK;
  65                 if (fl.fl6_flowlabel&IPV6_FLOWLABEL_MASK) {
  66                         flowlabel = fl6_sock_lookup(sk, fl.fl6_flowlabel);
  67                         if (flowlabel == NULL)
  68                                 return -EINVAL;
  69                         ipv6_addr_copy(&usin->sin6_addr, &flowlabel->dst);
  70                 }
  71         }
  72
  73         addr_type = ipv6_addr_type(&usin->sin6_addr);
  74
  75         if (addr_type == IPV6_ADDR_ANY) {
  76                 /*
  77                  *      connect to self
  78                  */
  79                 usin->sin6_addr.s6_addr[15] = 0x01;
  80         }
  81
  82         daddr = &usin->sin6_addr;
  83
  84         if (addr_type == IPV6_ADDR_MAPPED) {
  85                 struct sockaddr_in sin;
  86
  87                 if (__ipv6_only_sock(sk)) {
  88                         err = -ENETUNREACH;
  89                         goto out;
  90                 }
  91                 sin.sin_family = AF_INET;
  92                 sin.sin_addr.s_addr = daddr->s6_addr32[3];
  93                 sin.sin_port = usin->sin6_port;
  94
  95                 err = ip4_datagram_connect(sk,
  96                                            (struct sockaddr*) &sin,
  97                                            sizeof(sin));
  98
  99 ipv4_connected:
 100                 if (err)
 101                         goto out;
 102
 103                 ipv6_addr_set(&np->daddr, 0, 0, htonl(0x0000ffff), inet->daddr);
 104
 105                 if (ipv6_addr_any(&np->saddr)) {
 106                         ipv6_addr_set(&np->saddr, 0, 0, htonl(0x0000ffff),
 107                                       inet->saddr);
 108                 }
 109
 110                 if (ipv6_addr_any(&np->rcv_saddr)) {
 111                         ipv6_addr_set(&np->rcv_saddr, 0, 0, htonl(0x0000ffff),
 112                                       inet->rcv_saddr);
 113                 }
 114                 goto out;
 115         }
 116
 117         if (addr_type&IPV6_ADDR_LINKLOCAL) {
 118                 if (addr_len >= sizeof(struct sockaddr_in6) &&
 119                     usin->sin6_scope_id) {
 120                         if (sk->sk_bound_dev_if &&
 121                             sk->sk_bound_dev_if != usin->sin6_scope_id) {
 122                                 err = -EINVAL;
 123                                 goto out;
 124                         }
 125                         sk->sk_bound_dev_if = usin->sin6_scope_id;
 126                         if (!sk->sk_bound_dev_if &&
 127                             (addr_type & IPV6_ADDR_MULTICAST))
 128                                 fl.oif = np->mcast_oif;
 129                 }
 130
 131                 /* Connect to link-local address requires an interface */
 132                 if (!sk->sk_bound_dev_if) {
 133                         err = -EINVAL;
 134                         goto out;
 135                 }
 136         }
 137
 138         ipv6_addr_copy(&np->daddr, daddr);
 139         np->flow_label = fl.fl6_flowlabel;
 140
 141         inet->dport = usin->sin6_port;
 142
 143         /*
 144          *      Check for a route to destination an obtain the
 145          *      destination cache for it.
 146          */
 147
 148         fl.proto = sk->sk_protocol;
 149         ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
 150         ipv6_addr_copy(&fl.fl6_src, &np->saddr);
 151         fl.oif = sk->sk_bound_dev_if;
 152         fl.fl_ip_dport = inet->dport;
 153         fl.fl_ip_sport = inet->sport;
 154
 155         if (!fl.oif && (addr_type&IPV6_ADDR_MULTICAST))
 156                 fl.oif = np->mcast_oif;
 157
 158         security_sk_classify_flow(sk, &fl);
 159
 160         if (flowlabel) {
 161                 if (flowlabel->opt && flowlabel->opt->srcrt) {
 162                         struct rt0_hdr *rt0 = (struct rt0_hdr *) flowlabel->opt->srcrt;
 163                         ipv6_addr_copy(&final, &fl.fl6_dst);
 164                         ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
 165                         final_p = &final;
 166                 }
 167         } else if (np->opt && np->opt->srcrt) {
 168                 struct rt0_hdr *rt0 = (struct rt0_hdr *)np->opt->srcrt;
 169                 ipv6_addr_copy(&final, &fl.fl6_dst);
 170                 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
 171                 final_p = &final;
 172         }
 173
 174         err = ip6_dst_lookup(sk, &dst, &fl);
 175         if (err)
 176                 goto out;
 177         if (final_p)
 178                 ipv6_addr_copy(&fl.fl6_dst, final_p);
 179
 180         if ((err = xfrm_lookup(&dst, &fl, sk, 1)) < 0)
 181                 goto out;
 182
 183         /* source address lookup done in ip6_dst_lookup */
 184
 185         if (ipv6_addr_any(&np->saddr))
 186                 ipv6_addr_copy(&np->saddr, &fl.fl6_src);
 187
 188         if (ipv6_addr_any(&np->rcv_saddr)) {
 189                 ipv6_addr_copy(&np->rcv_saddr, &fl.fl6_src);
 190                 inet->rcv_saddr = LOOPBACK4_IPV6;
 191         }
 192
 193         ip6_dst_store(sk, dst,
 194                       ipv6_addr_equal(&fl.fl6_dst, &np->daddr) ?
 195                       &np->daddr : NULL,
 196 #ifdef CONFIG_IPV6_SUBTREES
 197                       ipv6_addr_equal(&fl.fl6_src, &np->saddr) ?
 198                       &np->saddr :
 199 #endif
 200                       NULL);
 201
 202         sk->sk_state = TCP_ESTABLISHED;
 203 out:
 204         fl6_sock_release(flowlabel);
 205         return err;
 206 }
 207
 208 void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
 209                      __be16 port, u32 info, u8 *payload)
 210 {
 211         struct ipv6_pinfo *np  = inet6_sk(sk);
 212         struct icmp6hdr *icmph = (struct icmp6hdr *)skb->h.raw;
 213         struct sock_exterr_skb *serr;
 214
 215         if (!np->recverr)
 216                 return;
 217
 218         skb = skb_clone(skb, GFP_ATOMIC);
 219         if (!skb)
 220                 return;
 221
 222         serr = SKB_EXT_ERR(skb);
 223         serr->ee.ee_errno = err;
 224         serr->ee.ee_origin = SO_EE_ORIGIN_ICMP6;
 225         serr->ee.ee_type = icmph->icmp6_type;
 226         serr->ee.ee_code = icmph->icmp6_code;
 227         serr->ee.ee_pad = 0;
 228         serr->ee.ee_info = info;
 229         serr->ee.ee_data = 0;
 230         serr->addr_offset = (u8 *)&(((struct ipv6hdr *)(icmph + 1))->daddr) -
 231                                   skb_network_header(skb);
 232         serr->port = port;
 233
 234         skb->h.raw = payload;
 235         __skb_pull(skb, payload - skb->data);
 236
 237         if (sock_queue_err_skb(sk, skb))
 238                 kfree_skb(skb);
 239 }
 240
 241 void ipv6_local_error(struct sock *sk, int err, struct flowi *fl, u32 info)
 242 {
 243         struct ipv6_pinfo *np = inet6_sk(sk);
 244         struct sock_exterr_skb *serr;
 245         struct ipv6hdr *iph;
 246         struct sk_buff *skb;
 247
 248         if (!np->recverr)
 249                 return;
 250
 251         skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
 252         if (!skb)
 253                 return;
 254
 255         skb_put(skb, sizeof(struct ipv6hdr));
 256         skb_reset_network_header(skb);
 257         iph = skb->nh.ipv6h;
 258         ipv6_addr_copy(&iph->daddr, &fl->fl6_dst);
 259
 260         serr = SKB_EXT_ERR(skb);
 261         serr->ee.ee_errno = err;
 262         serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
 263         serr->ee.ee_type = 0;
 264         serr->ee.ee_code = 0;
 265         serr->ee.ee_pad = 0;
 266         serr->ee.ee_info = info;
 267         serr->ee.ee_data = 0;
 268         serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
 269         serr->port = fl->fl_ip_dport;
 270
 271         skb->h.raw = skb->tail;
 272         __skb_pull(skb, skb->tail - skb->data);
 273
 274         if (sock_queue_err_skb(sk, skb))
 275                 kfree_skb(skb);
 276 }
 277
 278 /*
 279  *      Handle MSG_ERRQUEUE
 280  */
 281 int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len)
 282 {
 283         struct ipv6_pinfo *np = inet6_sk(sk);
 284         struct sock_exterr_skb *serr;
 285         struct sk_buff *skb, *skb2;
 286         struct sockaddr_in6 *sin;
 287         struct {
 288                 struct sock_extended_err ee;
 289                 struct sockaddr_in6      offender;
 290         } errhdr;
 291         int err;
 292         int copied;
 293
 294         err = -EAGAIN;
 295         skb = skb_dequeue(&sk->sk_error_queue);
 296         if (skb == NULL)
 297                 goto out;
 298
 299         copied = skb->len;
 300         if (copied > len) {
 301                 msg->msg_flags |= MSG_TRUNC;
 302                 copied = len;
 303         }
 304         err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
 305         if (err)
 306                 goto out_free_skb;
 307
 308         sock_recv_timestamp(msg, sk, skb);
 309
 310         serr = SKB_EXT_ERR(skb);
 311
 312         sin = (struct sockaddr_in6 *)msg->msg_name;
 313         if (sin) {
 314                 const unsigned char *nh = skb_network_header(skb);
 315                 sin->sin6_family = AF_INET6;
 316                 sin->sin6_flowinfo = 0;
 317                 sin->sin6_port = serr->port;
 318                 sin->sin6_scope_id = 0;
 319                 if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6) {
 320                         ipv6_addr_copy(&sin->sin6_addr,
 321                                   (struct in6_addr *)(nh + serr->addr_offset));
 322                         if (np->sndflow)
 323                                 sin->sin6_flowinfo =
 324                                         (*(__be32 *)(nh + serr->addr_offset - 24) &
 325                                          IPV6_FLOWINFO_MASK);
 326                         if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
 327                                 sin->sin6_scope_id = IP6CB(skb)->iif;
 328                 } else {
 329                         ipv6_addr_set(&sin->sin6_addr, 0, 0,
 330                                       htonl(0xffff),
 331                                       *(__be32 *)(nh + serr->addr_offset));
 332                 }
 333         }
 334
 335         memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
 336         sin = &errhdr.offender;
 337         sin->sin6_family = AF_UNSPEC;
 338         if (serr->ee.ee_origin != SO_EE_ORIGIN_LOCAL) {
 339                 sin->sin6_family = AF_INET6;
 340                 sin->sin6_flowinfo = 0;
 341                 sin->sin6_scope_id = 0;
 342                 if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6) {
 343                         ipv6_addr_copy(&sin->sin6_addr, &skb->nh.ipv6h->saddr);
 344                         if (np->rxopt.all)
 345                                 datagram_recv_ctl(sk, msg, skb);
 346                         if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
 347                                 sin->sin6_scope_id = IP6CB(skb)->iif;
 348                 } else {
 349                         struct inet_sock *inet = inet_sk(sk);
 350
 351                         ipv6_addr_set(&sin->sin6_addr, 0, 0,
 352                                       htonl(0xffff),
 353                                       skb->nh.iph->saddr);
 354                         if (inet->cmsg_flags)
 355                                 ip_cmsg_recv(msg, skb);
 356                 }
 357         }
 358
 359         put_cmsg(msg, SOL_IPV6, IPV6_RECVERR, sizeof(errhdr), &errhdr);
 360
 361         /* Now we could try to dump offended packet options */
 362
 363         msg->msg_flags |= MSG_ERRQUEUE;
 364         err = copied;
 365
 366         /* Reset and regenerate socket error */
 367         spin_lock_bh(&sk->sk_error_queue.lock);
 368         sk->sk_err = 0;
 369         if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
 370                 sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
 371                 spin_unlock_bh(&sk->sk_error_queue.lock);
 372                 sk->sk_error_report(sk);
 373         } else {
 374                 spin_unlock_bh(&sk->sk_error_queue.lock);
 375         }
 376
 377 out_free_skb:
 378         kfree_skb(skb);
 379 out:
 380         return err;
 381 }
 382
 383
 384
 385 int datagram_recv_ctl(struct sock *sk, struct msghdr *msg, struct sk_buff *skb)
 386 {
 387         struct ipv6_pinfo *np = inet6_sk(sk);
 388         struct inet6_skb_parm *opt = IP6CB(skb);
 389         unsigned char *nh = skb_network_header(skb);
 390
 391         if (np->rxopt.bits.rxinfo) {
 392                 struct in6_pktinfo src_info;
 393
 394                 src_info.ipi6_ifindex = opt->iif;
 395                 ipv6_addr_copy(&src_info.ipi6_addr, &skb->nh.ipv6h->daddr);
 396                 put_cmsg(msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info);
 397         }
 398
 399         if (np->rxopt.bits.rxhlim) {
 400                 int hlim = skb->nh.ipv6h->hop_limit;
 401                 put_cmsg(msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
 402         }
 403
 404         if (np->rxopt.bits.rxtclass) {
 405                 int tclass = (ntohl(*(__be32 *)skb->nh.ipv6h) >> 20) & 0xff;
 406                 put_cmsg(msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
 407         }
 408
 409         if (np->rxopt.bits.rxflow && (*(__be32 *)nh & IPV6_FLOWINFO_MASK)) {
 410                 __be32 flowinfo = *(__be32 *)nh & IPV6_FLOWINFO_MASK;
 411                 put_cmsg(msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
 412         }
 413
 414         /* HbH is allowed only once */
 415         if (np->rxopt.bits.hopopts && opt->hop) {
 416                 u8 *ptr = nh + opt->hop;
 417                 put_cmsg(msg, SOL_IPV6, IPV6_HOPOPTS, (ptr[1]+1)<<3, ptr);
 418         }
 419
 420         if (opt->lastopt &&
 421             (np->rxopt.bits.dstopts || np->rxopt.bits.srcrt)) {
 422                 /*
 423                  * Silly enough, but we need to reparse in order to
 424                  * report extension headers (except for HbH)
 425                  * in order.
 426                  *
 427                  * Also note that IPV6_RECVRTHDRDSTOPTS is NOT
 428                  * (and WILL NOT be) defined because
 429                  * IPV6_RECVDSTOPTS is more generic. --yoshfuji
 430                  */
 431                 unsigned int off = sizeof(struct ipv6hdr);
 432                 u8 nexthdr = skb->nh.ipv6h->nexthdr;
 433
 434                 while (off <= opt->lastopt) {
 435                         unsigned len;
 436                         u8 *ptr = nh + off;
 437
 438                         switch(nexthdr) {
 439                         case IPPROTO_DSTOPTS:
 440                                 nexthdr = ptr[0];
 441                                 len = (ptr[1] + 1) << 3;
 442                                 if (np->rxopt.bits.dstopts)
 443                                         put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, len, ptr);
 444                                 break;
 445                         case IPPROTO_ROUTING:
 446                                 nexthdr = ptr[0];
 447                                 len = (ptr[1] + 1) << 3;
 448                                 if (np->rxopt.bits.srcrt)
 449                                         put_cmsg(msg, SOL_IPV6, IPV6_RTHDR, len, ptr);
 450                                 break;
 451                         case IPPROTO_AH:
 452                                 nexthdr = ptr[0];
 453                                 len = (ptr[1] + 2) << 2;
 454                                 break;
 455                         default:
 456                                 nexthdr = ptr[0];
 457                                 len = (ptr[1] + 1) << 3;
 458                                 break;
 459                         }
 460
 461                         off += len;
 462                 }
 463         }
 464
 465         /* socket options in old style */
 466         if (np->rxopt.bits.rxoinfo) {
 467                 struct in6_pktinfo src_info;
 468
 469                 src_info.ipi6_ifindex = opt->iif;
 470                 ipv6_addr_copy(&src_info.ipi6_addr, &skb->nh.ipv6h->daddr);
 471                 put_cmsg(msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
 472         }
 473         if (np->rxopt.bits.rxohlim) {
 474                 int hlim = skb->nh.ipv6h->hop_limit;
 475                 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
 476         }
 477         if (np->rxopt.bits.ohopopts && opt->hop) {
 478                 u8 *ptr = nh + opt->hop;
 479                 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPOPTS, (ptr[1]+1)<<3, ptr);
 480         }
 481         if (np->rxopt.bits.odstopts && opt->dst0) {
 482                 u8 *ptr = nh + opt->dst0;
 483                 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
 484         }
 485         if (np->rxopt.bits.osrcrt && opt->srcrt) {
 486                 struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(nh + opt->srcrt);
 487                 put_cmsg(msg, SOL_IPV6, IPV6_2292RTHDR, (rthdr->hdrlen+1) << 3, rthdr);
 488         }
 489         if (np->rxopt.bits.odstopts && opt->dst1) {
 490                 u8 *ptr = nh + opt->dst1;
 491                 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
 492         }
 493         return 0;
 494 }
 495
 496 int datagram_send_ctl(struct msghdr *msg, struct flowi *fl,
 497                       struct ipv6_txoptions *opt,
 498                       int *hlimit, int *tclass)
 499 {
 500         struct in6_pktinfo *src_info;
 501         struct cmsghdr *cmsg;
 502         struct ipv6_rt_hdr *rthdr;
 503         struct ipv6_opt_hdr *hdr;
 504         int len;
 505         int err = 0;
 506
 507         for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
 508                 int addr_type;
 509                 struct net_device *dev = NULL;
 510
 511                 if (!CMSG_OK(msg, cmsg)) {
 512                         err = -EINVAL;
 513                         goto exit_f;
 514                 }
 515
 516                 if (cmsg->cmsg_level != SOL_IPV6)
 517                         continue;
 518
 519                 switch (cmsg->cmsg_type) {
 520                 case IPV6_PKTINFO:
 521                 case IPV6_2292PKTINFO:
 522                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct in6_pktinfo))) {
 523                                 err = -EINVAL;
 524                                 goto exit_f;
 525                         }
 526
 527                         src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
 528
 529                         if (src_info->ipi6_ifindex) {
 530                                 if (fl->oif && src_info->ipi6_ifindex != fl->oif)
 531                                         return -EINVAL;
 532                                 fl->oif = src_info->ipi6_ifindex;
 533                         }
 534
 535                         addr_type = ipv6_addr_type(&src_info->ipi6_addr);
 536
 537                         if (addr_type == IPV6_ADDR_ANY)
 538                                 break;
 539
 540                         if (addr_type & IPV6_ADDR_LINKLOCAL) {
 541                                 if (!src_info->ipi6_ifindex)
 542                                         return -EINVAL;
 543                                 else {
 544                                         dev = dev_get_by_index(src_info->ipi6_ifindex);
 545                                         if (!dev)
 546                                                 return -ENODEV;
 547                                 }
 548                         }
 549                         if (!ipv6_chk_addr(&src_info->ipi6_addr, dev, 0)) {
 550                                 if (dev)
 551                                         dev_put(dev);
 552                                 err = -EINVAL;
 553                                 goto exit_f;
 554                         }
 555                         if (dev)
 556                                 dev_put(dev);
 557
 558                         ipv6_addr_copy(&fl->fl6_src, &src_info->ipi6_addr);
 559                         break;
 560
 561                 case IPV6_FLOWINFO:
 562                         if (cmsg->cmsg_len < CMSG_LEN(4)) {
 563                                 err = -EINVAL;
 564                                 goto exit_f;
 565                         }
 566
 567                         if (fl->fl6_flowlabel&IPV6_FLOWINFO_MASK) {
 568                                 if ((fl->fl6_flowlabel^*(__be32 *)CMSG_DATA(cmsg))&~IPV6_FLOWINFO_MASK) {
 569                                         err = -EINVAL;
 570                                         goto exit_f;
 571                                 }
 572                         }
 573                         fl->fl6_flowlabel = IPV6_FLOWINFO_MASK & *(__be32 *)CMSG_DATA(cmsg);
 574                         break;
 575
 576                 case IPV6_2292HOPOPTS:
 577                 case IPV6_HOPOPTS:
 578                         if (opt->hopopt || cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
 579                                 err = -EINVAL;
 580                                 goto exit_f;
 581                         }
 582
 583                         hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
 584                         len = ((hdr->hdrlen + 1) << 3);
 585                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
 586                                 err = -EINVAL;
 587                                 goto exit_f;
 588                         }
 589                         if (!capable(CAP_NET_RAW)) {
 590                                 err = -EPERM;
 591                                 goto exit_f;
 592                         }
 593                         opt->opt_nflen += len;
 594                         opt->hopopt = hdr;
 595                         break;
 596
 597                 case IPV6_2292DSTOPTS:
 598                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
 599                                 err = -EINVAL;
 600                                 goto exit_f;
 601                         }
 602
 603                         hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
 604                         len = ((hdr->hdrlen + 1) << 3);
 605                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
 606                                 err = -EINVAL;
 607                                 goto exit_f;
 608                         }
 609                         if (!capable(CAP_NET_RAW)) {
 610                                 err = -EPERM;
 611                                 goto exit_f;
 612                         }
 613                         if (opt->dst1opt) {
 614                                 err = -EINVAL;
 615                                 goto exit_f;
 616                         }
 617                         opt->opt_flen += len;
 618                         opt->dst1opt = hdr;
 619                         break;
 620
 621                 case IPV6_DSTOPTS:
 622                 case IPV6_RTHDRDSTOPTS:
 623                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
 624                                 err = -EINVAL;
 625                                 goto exit_f;
 626                         }
 627
 628                         hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
 629                         len = ((hdr->hdrlen + 1) << 3);
 630                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
 631                                 err = -EINVAL;
 632                                 goto exit_f;
 633                         }
 634                         if (!capable(CAP_NET_RAW)) {
 635                                 err = -EPERM;
 636                                 goto exit_f;
 637                         }
 638                         if (cmsg->cmsg_type == IPV6_DSTOPTS) {
 639                                 opt->opt_flen += len;
 640                                 opt->dst1opt = hdr;
 641                         } else {
 642                                 opt->opt_nflen += len;
 643                                 opt->dst0opt = hdr;
 644                         }
 645                         break;
 646
 647                 case IPV6_2292RTHDR:
 648                 case IPV6_RTHDR:
 649                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_rt_hdr))) {
 650                                 err = -EINVAL;
 651                                 goto exit_f;
 652                         }
 653
 654                         rthdr = (struct ipv6_rt_hdr *)CMSG_DATA(cmsg);
 655
 656                         switch (rthdr->type) {
 657                         case IPV6_SRCRT_TYPE_0:
 658 #ifdef CONFIG_IPV6_MIP6
 659                         case IPV6_SRCRT_TYPE_2:
 660 #endif
 661                                 break;
 662                         default:
 663                                 err = -EINVAL;
 664                                 goto exit_f;
 665                         }
 666
 667                         len = ((rthdr->hdrlen + 1) << 3);
 668
 669                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
 670                                 err = -EINVAL;
 671                                 goto exit_f;
 672                         }
 673
 674                         /* segments left must also match */
 675                         if ((rthdr->hdrlen >> 1) != rthdr->segments_left) {
 676                                 err = -EINVAL;
 677                                 goto exit_f;
 678                         }
 679
 680                         opt->opt_nflen += len;
 681                         opt->srcrt = rthdr;
 682
 683                         if (cmsg->cmsg_type == IPV6_2292RTHDR && opt->dst1opt) {
 684                                 int dsthdrlen = ((opt->dst1opt->hdrlen+1)<<3);
 685
 686                                 opt->opt_nflen += dsthdrlen;
 687                                 opt->dst0opt = opt->dst1opt;
 688                                 opt->dst1opt = NULL;
 689                                 opt->opt_flen -= dsthdrlen;
 690                         }
 691
 692                         break;
 693
 694                 case IPV6_2292HOPLIMIT:
 695                 case IPV6_HOPLIMIT:
 696                         if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
 697                                 err = -EINVAL;
 698                                 goto exit_f;
 699                         }
 700
 701                         *hlimit = *(int *)CMSG_DATA(cmsg);
 702                         break;
 703
 704                 case IPV6_TCLASS:
 705                     {
 706                         int tc;
 707
 708                         err = -EINVAL;
 709                         if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
 710                                 goto exit_f;
 711                         }
 712
 713                         tc = *(int *)CMSG_DATA(cmsg);
 714                         if (tc < -1 || tc > 0xff)
 715                                 goto exit_f;
 716
 717                         err = 0;
 718                         *tclass = tc;
 719
 720                         break;
 721                     }
 722                 default:
 723                         LIMIT_NETDEBUG(KERN_DEBUG "invalid cmsg type: %d\n",
 724                                        cmsg->cmsg_type);
 725                         err = -EINVAL;
 726                         break;
 727                 };
 728         }
 729
 730 exit_f:
 731         return err;
 732 }