SAFE public projects git trees. - safe/jmp/linux-2.6/blob - 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  *      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 #include <linux/slab.h>
  25
  26 #include <net/ipv6.h>
  27 #include <net/ndisc.h>
  28 #include <net/addrconf.h>
  29 #include <net/transp_v6.h>
  30 #include <net/ip6_route.h>
  31 #include <net/tcp_states.h>
  32
  33 #include <linux/errqueue.h>
  34 #include <asm/uaccess.h>
  35
  36 int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
  37 {
  38         struct sockaddr_in6     *usin = (struct sockaddr_in6 *) uaddr;
  39         struct inet_sock        *inet = inet_sk(sk);
  40         struct ipv6_pinfo       *np = inet6_sk(sk);
  41         struct in6_addr         *daddr, *final_p = NULL, final;
  42         struct dst_entry        *dst;
  43         struct flowi            fl;
  44         struct ip6_flowlabel    *flowlabel = NULL;
  45         int                     addr_type;
  46         int                     err;
  47
  48         if (usin->sin6_family == AF_INET) {
  49                 if (__ipv6_only_sock(sk))
  50                         return -EAFNOSUPPORT;
  51                 err = ip4_datagram_connect(sk, uaddr, addr_len);
  52                 goto ipv4_connected;
  53         }
  54
  55         if (addr_len < SIN6_LEN_RFC2133)
  56                 return -EINVAL;
  57
  58         if (usin->sin6_family != AF_INET6)
  59                 return -EAFNOSUPPORT;
  60
  61         memset(&fl, 0, sizeof(fl));
  62         if (np->sndflow) {
  63                 fl.fl6_flowlabel = usin->sin6_flowinfo&IPV6_FLOWINFO_MASK;
  64                 if (fl.fl6_flowlabel&IPV6_FLOWLABEL_MASK) {
  65                         flowlabel = fl6_sock_lookup(sk, fl.fl6_flowlabel);
  66                         if (flowlabel == NULL)
  67                                 return -EINVAL;
  68                         ipv6_addr_copy(&usin->sin6_addr, &flowlabel->dst);
  69                 }
  70         }
  71
  72         addr_type = ipv6_addr_type(&usin->sin6_addr);
  73
  74         if (addr_type == IPV6_ADDR_ANY) {
  75                 /*
  76                  *      connect to self
  77                  */
  78                 usin->sin6_addr.s6_addr[15] = 0x01;
  79         }
  80
  81         daddr = &usin->sin6_addr;
  82
  83         if (addr_type == IPV6_ADDR_MAPPED) {
  84                 struct sockaddr_in sin;
  85
  86                 if (__ipv6_only_sock(sk)) {
  87                         err = -ENETUNREACH;
  88                         goto out;
  89                 }
  90                 sin.sin_family = AF_INET;
  91                 sin.sin_addr.s_addr = daddr->s6_addr32[3];
  92                 sin.sin_port = usin->sin6_port;
  93
  94                 err = ip4_datagram_connect(sk,
  95                                            (struct sockaddr*) &sin,
  96                                            sizeof(sin));
  97
  98 ipv4_connected:
  99                 if (err)
 100                         goto out;
 101
 102                 ipv6_addr_set_v4mapped(inet->inet_daddr, &np->daddr);
 103
 104                 if (ipv6_addr_any(&np->saddr))
 105                         ipv6_addr_set_v4mapped(inet->inet_saddr, &np->saddr);
 106
 107                 if (ipv6_addr_any(&np->rcv_saddr))
 108                         ipv6_addr_set_v4mapped(inet->inet_rcv_saddr,
 109                                                &np->rcv_saddr);
 110
 111                 goto out;
 112         }
 113
 114         if (addr_type&IPV6_ADDR_LINKLOCAL) {
 115                 if (addr_len >= sizeof(struct sockaddr_in6) &&
 116                     usin->sin6_scope_id) {
 117                         if (sk->sk_bound_dev_if &&
 118                             sk->sk_bound_dev_if != usin->sin6_scope_id) {
 119                                 err = -EINVAL;
 120                                 goto out;
 121                         }
 122                         sk->sk_bound_dev_if = usin->sin6_scope_id;
 123                 }
 124
 125                 if (!sk->sk_bound_dev_if && (addr_type & IPV6_ADDR_MULTICAST))
 126                         sk->sk_bound_dev_if = np->mcast_oif;
 127
 128                 /* Connect to link-local address requires an interface */
 129                 if (!sk->sk_bound_dev_if) {
 130                         err = -EINVAL;
 131                         goto out;
 132                 }
 133         }
 134
 135         ipv6_addr_copy(&np->daddr, daddr);
 136         np->flow_label = fl.fl6_flowlabel;
 137
 138         inet->inet_dport = usin->sin6_port;
 139
 140         /*
 141          *      Check for a route to destination an obtain the
 142          *      destination cache for it.
 143          */
 144
 145         fl.proto = sk->sk_protocol;
 146         ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
 147         ipv6_addr_copy(&fl.fl6_src, &np->saddr);
 148         fl.oif = sk->sk_bound_dev_if;
 149         fl.mark = sk->sk_mark;
 150         fl.fl_ip_dport = inet->inet_dport;
 151         fl.fl_ip_sport = inet->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->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;
 206 out:
 207         fl6_sock_release(flowlabel);
 208         return err;
 209 }
 210
 211 void 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
 244 void 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 void ipv6_local_rxpmtu(struct sock *sk, struct flowi *fl, u32 mtu)
 282 {
 283         struct ipv6_pinfo *np = inet6_sk(sk);
 284         struct ipv6hdr *iph;
 285         struct sk_buff *skb;
 286         struct ip6_mtuinfo *mtu_info;
 287
 288         if (!np->rxopt.bits.rxpmtu)
 289                 return;
 290
 291         skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
 292         if (!skb)
 293                 return;
 294
 295         skb_put(skb, sizeof(struct ipv6hdr));
 296         skb_reset_network_header(skb);
 297         iph = ipv6_hdr(skb);
 298         ipv6_addr_copy(&iph->daddr, &fl->fl6_dst);
 299
 300         mtu_info = IP6CBMTU(skb);
 301         if (!mtu_info) {
 302                 kfree_skb(skb);
 303                 return;
 304         }
 305
 306         mtu_info->ip6m_mtu = mtu;
 307         mtu_info->ip6m_addr.sin6_family = AF_INET6;
 308         mtu_info->ip6m_addr.sin6_port = 0;
 309         mtu_info->ip6m_addr.sin6_flowinfo = 0;
 310         mtu_info->ip6m_addr.sin6_scope_id = fl->oif;
 311         ipv6_addr_copy(&mtu_info->ip6m_addr.sin6_addr, &ipv6_hdr(skb)->daddr);
 312
 313         __skb_pull(skb, skb_tail_pointer(skb) - skb->data);
 314         skb_reset_transport_header(skb);
 315
 316         skb = xchg(&np->rxpmtu, skb);
 317         kfree_skb(skb);
 318 }
 319
 320 /*
 321  *      Handle MSG_ERRQUEUE
 322  */
 323 int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len)
 324 {
 325         struct ipv6_pinfo *np = inet6_sk(sk);
 326         struct sock_exterr_skb *serr;
 327         struct sk_buff *skb, *skb2;
 328         struct sockaddr_in6 *sin;
 329         struct {
 330                 struct sock_extended_err ee;
 331                 struct sockaddr_in6      offender;
 332         } errhdr;
 333         int err;
 334         int copied;
 335
 336         err = -EAGAIN;
 337         skb = skb_dequeue(&sk->sk_error_queue);
 338         if (skb == NULL)
 339                 goto out;
 340
 341         copied = skb->len;
 342         if (copied > len) {
 343                 msg->msg_flags |= MSG_TRUNC;
 344                 copied = len;
 345         }
 346         err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
 347         if (err)
 348                 goto out_free_skb;
 349
 350         sock_recv_timestamp(msg, sk, skb);
 351
 352         serr = SKB_EXT_ERR(skb);
 353
 354         sin = (struct sockaddr_in6 *)msg->msg_name;
 355         if (sin) {
 356                 const unsigned char *nh = skb_network_header(skb);
 357                 sin->sin6_family = AF_INET6;
 358                 sin->sin6_flowinfo = 0;
 359                 sin->sin6_port = serr->port;
 360                 sin->sin6_scope_id = 0;
 361                 if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6) {
 362                         ipv6_addr_copy(&sin->sin6_addr,
 363                                   (struct in6_addr *)(nh + serr->addr_offset));
 364                         if (np->sndflow)
 365                                 sin->sin6_flowinfo =
 366                                         (*(__be32 *)(nh + serr->addr_offset - 24) &
 367                                          IPV6_FLOWINFO_MASK);
 368                         if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
 369                                 sin->sin6_scope_id = IP6CB(skb)->iif;
 370                 } else {
 371                         ipv6_addr_set_v4mapped(*(__be32 *)(nh + serr->addr_offset),
 372                                                &sin->sin6_addr);
 373                 }
 374         }
 375
 376         memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
 377         sin = &errhdr.offender;
 378         sin->sin6_family = AF_UNSPEC;
 379         if (serr->ee.ee_origin != SO_EE_ORIGIN_LOCAL) {
 380                 sin->sin6_family = AF_INET6;
 381                 sin->sin6_flowinfo = 0;
 382                 sin->sin6_scope_id = 0;
 383                 if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6) {
 384                         ipv6_addr_copy(&sin->sin6_addr, &ipv6_hdr(skb)->saddr);
 385                         if (np->rxopt.all)
 386                                 datagram_recv_ctl(sk, msg, skb);
 387                         if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
 388                                 sin->sin6_scope_id = IP6CB(skb)->iif;
 389                 } else {
 390                         struct inet_sock *inet = inet_sk(sk);
 391
 392                         ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
 393                                                &sin->sin6_addr);
 394                         if (inet->cmsg_flags)
 395                                 ip_cmsg_recv(msg, skb);
 396                 }
 397         }
 398
 399         put_cmsg(msg, SOL_IPV6, IPV6_RECVERR, sizeof(errhdr), &errhdr);
 400
 401         /* Now we could try to dump offended packet options */
 402
 403         msg->msg_flags |= MSG_ERRQUEUE;
 404         err = copied;
 405
 406         /* Reset and regenerate socket error */
 407         spin_lock_bh(&sk->sk_error_queue.lock);
 408         sk->sk_err = 0;
 409         if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
 410                 sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
 411                 spin_unlock_bh(&sk->sk_error_queue.lock);
 412                 sk->sk_error_report(sk);
 413         } else {
 414                 spin_unlock_bh(&sk->sk_error_queue.lock);
 415         }
 416
 417 out_free_skb:
 418         kfree_skb(skb);
 419 out:
 420         return err;
 421 }
 422
 423 /*
 424  *      Handle IPV6_RECVPATHMTU
 425  */
 426 int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len)
 427 {
 428         struct ipv6_pinfo *np = inet6_sk(sk);
 429         struct sk_buff *skb;
 430         struct sockaddr_in6 *sin;
 431         struct ip6_mtuinfo mtu_info;
 432         int err;
 433         int copied;
 434
 435         err = -EAGAIN;
 436         skb = xchg(&np->rxpmtu, NULL);
 437         if (skb == NULL)
 438                 goto out;
 439
 440         copied = skb->len;
 441         if (copied > len) {
 442                 msg->msg_flags |= MSG_TRUNC;
 443                 copied = len;
 444         }
 445         err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
 446         if (err)
 447                 goto out_free_skb;
 448
 449         sock_recv_timestamp(msg, sk, skb);
 450
 451         memcpy(&mtu_info, IP6CBMTU(skb), sizeof(mtu_info));
 452
 453         sin = (struct sockaddr_in6 *)msg->msg_name;
 454         if (sin) {
 455                 sin->sin6_family = AF_INET6;
 456                 sin->sin6_flowinfo = 0;
 457                 sin->sin6_port = 0;
 458                 sin->sin6_scope_id = mtu_info.ip6m_addr.sin6_scope_id;
 459                 ipv6_addr_copy(&sin->sin6_addr, &mtu_info.ip6m_addr.sin6_addr);
 460         }
 461
 462         put_cmsg(msg, SOL_IPV6, IPV6_PATHMTU, sizeof(mtu_info), &mtu_info);
 463
 464         err = copied;
 465
 466 out_free_skb:
 467         kfree_skb(skb);
 468 out:
 469         return err;
 470 }
 471
 472
 473 int datagram_recv_ctl(struct sock *sk, struct msghdr *msg, struct sk_buff *skb)
 474 {
 475         struct ipv6_pinfo *np = inet6_sk(sk);
 476         struct inet6_skb_parm *opt = IP6CB(skb);
 477         unsigned char *nh = skb_network_header(skb);
 478
 479         if (np->rxopt.bits.rxinfo) {
 480                 struct in6_pktinfo src_info;
 481
 482                 src_info.ipi6_ifindex = opt->iif;
 483                 ipv6_addr_copy(&src_info.ipi6_addr, &ipv6_hdr(skb)->daddr);
 484                 put_cmsg(msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info);
 485         }
 486
 487         if (np->rxopt.bits.rxhlim) {
 488                 int hlim = ipv6_hdr(skb)->hop_limit;
 489                 put_cmsg(msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
 490         }
 491
 492         if (np->rxopt.bits.rxtclass) {
 493                 int tclass = (ntohl(*(__be32 *)ipv6_hdr(skb)) >> 20) & 0xff;
 494                 put_cmsg(msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
 495         }
 496
 497         if (np->rxopt.bits.rxflow && (*(__be32 *)nh & IPV6_FLOWINFO_MASK)) {
 498                 __be32 flowinfo = *(__be32 *)nh & IPV6_FLOWINFO_MASK;
 499                 put_cmsg(msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
 500         }
 501
 502         /* HbH is allowed only once */
 503         if (np->rxopt.bits.hopopts && opt->hop) {
 504                 u8 *ptr = nh + opt->hop;
 505                 put_cmsg(msg, SOL_IPV6, IPV6_HOPOPTS, (ptr[1]+1)<<3, ptr);
 506         }
 507
 508         if (opt->lastopt &&
 509             (np->rxopt.bits.dstopts || np->rxopt.bits.srcrt)) {
 510                 /*
 511                  * Silly enough, but we need to reparse in order to
 512                  * report extension headers (except for HbH)
 513                  * in order.
 514                  *
 515                  * Also note that IPV6_RECVRTHDRDSTOPTS is NOT
 516                  * (and WILL NOT be) defined because
 517                  * IPV6_RECVDSTOPTS is more generic. --yoshfuji
 518                  */
 519                 unsigned int off = sizeof(struct ipv6hdr);
 520                 u8 nexthdr = ipv6_hdr(skb)->nexthdr;
 521
 522                 while (off <= opt->lastopt) {
 523                         unsigned len;
 524                         u8 *ptr = nh + off;
 525
 526                         switch(nexthdr) {
 527                         case IPPROTO_DSTOPTS:
 528                                 nexthdr = ptr[0];
 529                                 len = (ptr[1] + 1) << 3;
 530                                 if (np->rxopt.bits.dstopts)
 531                                         put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, len, ptr);
 532                                 break;
 533                         case IPPROTO_ROUTING:
 534                                 nexthdr = ptr[0];
 535                                 len = (ptr[1] + 1) << 3;
 536                                 if (np->rxopt.bits.srcrt)
 537                                         put_cmsg(msg, SOL_IPV6, IPV6_RTHDR, len, ptr);
 538                                 break;
 539                         case IPPROTO_AH:
 540                                 nexthdr = ptr[0];
 541                                 len = (ptr[1] + 2) << 2;
 542                                 break;
 543                         default:
 544                                 nexthdr = ptr[0];
 545                                 len = (ptr[1] + 1) << 3;
 546                                 break;
 547                         }
 548
 549                         off += len;
 550                 }
 551         }
 552
 553         /* socket options in old style */
 554         if (np->rxopt.bits.rxoinfo) {
 555                 struct in6_pktinfo src_info;
 556
 557                 src_info.ipi6_ifindex = opt->iif;
 558                 ipv6_addr_copy(&src_info.ipi6_addr, &ipv6_hdr(skb)->daddr);
 559                 put_cmsg(msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
 560         }
 561         if (np->rxopt.bits.rxohlim) {
 562                 int hlim = ipv6_hdr(skb)->hop_limit;
 563                 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
 564         }
 565         if (np->rxopt.bits.ohopopts && opt->hop) {
 566                 u8 *ptr = nh + opt->hop;
 567                 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPOPTS, (ptr[1]+1)<<3, ptr);
 568         }
 569         if (np->rxopt.bits.odstopts && opt->dst0) {
 570                 u8 *ptr = nh + opt->dst0;
 571                 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
 572         }
 573         if (np->rxopt.bits.osrcrt && opt->srcrt) {
 574                 struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(nh + opt->srcrt);
 575                 put_cmsg(msg, SOL_IPV6, IPV6_2292RTHDR, (rthdr->hdrlen+1) << 3, rthdr);
 576         }
 577         if (np->rxopt.bits.odstopts && opt->dst1) {
 578                 u8 *ptr = nh + opt->dst1;
 579                 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
 580         }
 581         return 0;
 582 }
 583
 584 int datagram_send_ctl(struct net *net,
 585                       struct msghdr *msg, struct flowi *fl,
 586                       struct ipv6_txoptions *opt,
 587                       int *hlimit, int *tclass, int *dontfrag)
 588 {
 589         struct in6_pktinfo *src_info;
 590         struct cmsghdr *cmsg;
 591         struct ipv6_rt_hdr *rthdr;
 592         struct ipv6_opt_hdr *hdr;
 593         int len;
 594         int err = 0;
 595
 596         for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
 597                 int addr_type;
 598
 599                 if (!CMSG_OK(msg, cmsg)) {
 600                         err = -EINVAL;
 601                         goto exit_f;
 602                 }
 603
 604                 if (cmsg->cmsg_level != SOL_IPV6)
 605                         continue;
 606
 607                 switch (cmsg->cmsg_type) {
 608                 case IPV6_PKTINFO:
 609                 case IPV6_2292PKTINFO:
 610                     {
 611                         struct net_device *dev = NULL;
 612
 613                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct in6_pktinfo))) {
 614                                 err = -EINVAL;
 615                                 goto exit_f;
 616                         }
 617
 618                         src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
 619
 620                         if (src_info->ipi6_ifindex) {
 621                                 if (fl->oif && src_info->ipi6_ifindex != fl->oif)
 622                                         return -EINVAL;
 623                                 fl->oif = src_info->ipi6_ifindex;
 624                         }
 625
 626                         addr_type = __ipv6_addr_type(&src_info->ipi6_addr);
 627
 628                         rcu_read_lock();
 629                         if (fl->oif) {
 630                                 dev = dev_get_by_index_rcu(net, fl->oif);
 631                                 if (!dev) {
 632                                         rcu_read_unlock();
 633                                         return -ENODEV;
 634                                 }
 635                         } else if (addr_type & IPV6_ADDR_LINKLOCAL) {
 636                                 rcu_read_unlock();
 637                                 return -EINVAL;
 638                         }
 639
 640                         if (addr_type != IPV6_ADDR_ANY) {
 641                                 int strict = __ipv6_addr_src_scope(addr_type) <= IPV6_ADDR_SCOPE_LINKLOCAL;
 642                                 if (!ipv6_chk_addr(net, &src_info->ipi6_addr,
 643                                                    strict ? dev : NULL, 0))
 644                                         err = -EINVAL;
 645                                 else
 646                                         ipv6_addr_copy(&fl->fl6_src, &src_info->ipi6_addr);
 647                         }
 648
 649                         rcu_read_unlock();
 650
 651                         if (err)
 652                                 goto exit_f;
 653
 654                         break;
 655                     }
 656
 657                 case IPV6_FLOWINFO:
 658                         if (cmsg->cmsg_len < CMSG_LEN(4)) {
 659                                 err = -EINVAL;
 660                                 goto exit_f;
 661                         }
 662
 663                         if (fl->fl6_flowlabel&IPV6_FLOWINFO_MASK) {
 664                                 if ((fl->fl6_flowlabel^*(__be32 *)CMSG_DATA(cmsg))&~IPV6_FLOWINFO_MASK) {
 665                                         err = -EINVAL;
 666                                         goto exit_f;
 667                                 }
 668                         }
 669                         fl->fl6_flowlabel = IPV6_FLOWINFO_MASK & *(__be32 *)CMSG_DATA(cmsg);
 670                         break;
 671
 672                 case IPV6_2292HOPOPTS:
 673                 case IPV6_HOPOPTS:
 674                         if (opt->hopopt || cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
 675                                 err = -EINVAL;
 676                                 goto exit_f;
 677                         }
 678
 679                         hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
 680                         len = ((hdr->hdrlen + 1) << 3);
 681                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
 682                                 err = -EINVAL;
 683                                 goto exit_f;
 684                         }
 685                         if (!capable(CAP_NET_RAW)) {
 686                                 err = -EPERM;
 687                                 goto exit_f;
 688                         }
 689                         opt->opt_nflen += len;
 690                         opt->hopopt = hdr;
 691                         break;
 692
 693                 case IPV6_2292DSTOPTS:
 694                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
 695                                 err = -EINVAL;
 696                                 goto exit_f;
 697                         }
 698
 699                         hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
 700                         len = ((hdr->hdrlen + 1) << 3);
 701                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
 702                                 err = -EINVAL;
 703                                 goto exit_f;
 704                         }
 705                         if (!capable(CAP_NET_RAW)) {
 706                                 err = -EPERM;
 707                                 goto exit_f;
 708                         }
 709                         if (opt->dst1opt) {
 710                                 err = -EINVAL;
 711                                 goto exit_f;
 712                         }
 713                         opt->opt_flen += len;
 714                         opt->dst1opt = hdr;
 715                         break;
 716
 717                 case IPV6_DSTOPTS:
 718                 case IPV6_RTHDRDSTOPTS:
 719                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
 720                                 err = -EINVAL;
 721                                 goto exit_f;
 722                         }
 723
 724                         hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
 725                         len = ((hdr->hdrlen + 1) << 3);
 726                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
 727                                 err = -EINVAL;
 728                                 goto exit_f;
 729                         }
 730                         if (!capable(CAP_NET_RAW)) {
 731                                 err = -EPERM;
 732                                 goto exit_f;
 733                         }
 734                         if (cmsg->cmsg_type == IPV6_DSTOPTS) {
 735                                 opt->opt_flen += len;
 736                                 opt->dst1opt = hdr;
 737                         } else {
 738                                 opt->opt_nflen += len;
 739                                 opt->dst0opt = hdr;
 740                         }
 741                         break;
 742
 743                 case IPV6_2292RTHDR:
 744                 case IPV6_RTHDR:
 745                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_rt_hdr))) {
 746                                 err = -EINVAL;
 747                                 goto exit_f;
 748                         }
 749
 750                         rthdr = (struct ipv6_rt_hdr *)CMSG_DATA(cmsg);
 751
 752                         switch (rthdr->type) {
 753 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
 754                         case IPV6_SRCRT_TYPE_2:
 755                                 if (rthdr->hdrlen != 2 ||
 756                                     rthdr->segments_left != 1) {
 757                                         err = -EINVAL;
 758                                         goto exit_f;
 759                                 }
 760                                 break;
 761 #endif
 762                         default:
 763                                 err = -EINVAL;
 764                                 goto exit_f;
 765                         }
 766
 767                         len = ((rthdr->hdrlen + 1) << 3);
 768
 769                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
 770                                 err = -EINVAL;
 771                                 goto exit_f;
 772                         }
 773
 774                         /* segments left must also match */
 775                         if ((rthdr->hdrlen >> 1) != rthdr->segments_left) {
 776                                 err = -EINVAL;
 777                                 goto exit_f;
 778                         }
 779
 780                         opt->opt_nflen += len;
 781                         opt->srcrt = rthdr;
 782
 783                         if (cmsg->cmsg_type == IPV6_2292RTHDR && opt->dst1opt) {
 784                                 int dsthdrlen = ((opt->dst1opt->hdrlen+1)<<3);
 785
 786                                 opt->opt_nflen += dsthdrlen;
 787                                 opt->dst0opt = opt->dst1opt;
 788                                 opt->dst1opt = NULL;
 789                                 opt->opt_flen -= dsthdrlen;
 790                         }
 791
 792                         break;
 793
 794                 case IPV6_2292HOPLIMIT:
 795                 case IPV6_HOPLIMIT:
 796                         if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
 797                                 err = -EINVAL;
 798                                 goto exit_f;
 799                         }
 800
 801                         *hlimit = *(int *)CMSG_DATA(cmsg);
 802                         if (*hlimit < -1 || *hlimit > 0xff) {
 803                                 err = -EINVAL;
 804                                 goto exit_f;
 805                         }
 806
 807                         break;
 808
 809                 case IPV6_TCLASS:
 810                     {
 811                         int tc;
 812
 813                         err = -EINVAL;
 814                         if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
 815                                 goto exit_f;
 816                         }
 817
 818                         tc = *(int *)CMSG_DATA(cmsg);
 819                         if (tc < -1 || tc > 0xff)
 820                                 goto exit_f;
 821
 822                         err = 0;
 823                         *tclass = tc;
 824
 825                         break;
 826                     }
 827
 828                 case IPV6_DONTFRAG:
 829                     {
 830                         int df;
 831
 832                         err = -EINVAL;
 833                         if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
 834                                 goto exit_f;
 835                         }
 836
 837                         df = *(int *)CMSG_DATA(cmsg);
 838                         if (df < 0 || df > 1)
 839                                 goto exit_f;
 840
 841                         err = 0;
 842                         *dontfrag = df;
 843
 844                         break;
 845                     }
 846                 default:
 847                         LIMIT_NETDEBUG(KERN_DEBUG "invalid cmsg type: %d\n",
 848                                        cmsg->cmsg_type);
 849                         err = -EINVAL;
 850                         goto exit_f;
 851                 }
 852         }
 853
 854 exit_f:
 855         return err;
 856 }