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 #include <linux/export.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 #include <net/dsfield.h>
  34
  35 #include <linux/errqueue.h>
  36 #include <asm/uaccess.h>
  37
  38 static bool ipv6_mapped_addr_any(const struct in6_addr *a)
  39 {
  40         return ipv6_addr_v4mapped(a) && (a->s6_addr32[3] == 0);
  41 }
  42
  43 int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
  44 {
  45         struct sockaddr_in6     *usin = (struct sockaddr_in6 *) uaddr;
  46         struct inet_sock        *inet = inet_sk(sk);
  47         struct ipv6_pinfo       *np = inet6_sk(sk);
  48         struct in6_addr         *daddr, *final_p, final;
  49         struct dst_entry        *dst;
  50         struct flowi6           fl6;
  51         struct ip6_flowlabel    *flowlabel = NULL;
  52         struct ipv6_txoptions   *opt;
  53         int                     addr_type;
  54         int                     err;
  55
  56         if (usin->sin6_family == AF_INET) {
  57                 if (__ipv6_only_sock(sk))
  58                         return -EAFNOSUPPORT;
  59                 err = ip4_datagram_connect(sk, uaddr, addr_len);
  60                 goto ipv4_connected;
  61         }
  62
  63         if (addr_len < SIN6_LEN_RFC2133)
  64                 return -EINVAL;
  65
  66         if (usin->sin6_family != AF_INET6)
  67                 return -EAFNOSUPPORT;
  68
  69         memset(&fl6, 0, sizeof(fl6));
  70         if (np->sndflow) {
  71                 fl6.flowlabel = usin->sin6_flowinfo&IPV6_FLOWINFO_MASK;
  72                 if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
  73                         flowlabel = fl6_sock_lookup(sk, fl6.flowlabel);
  74                         if (flowlabel == NULL)
  75                                 return -EINVAL;
  76                 }
  77         }
  78
  79         addr_type = ipv6_addr_type(&usin->sin6_addr);
  80
  81         if (addr_type == IPV6_ADDR_ANY) {
  82                 /*
  83                  *      connect to self
  84                  */
  85                 usin->sin6_addr.s6_addr[15] = 0x01;
  86         }
  87
  88         daddr = &usin->sin6_addr;
  89
  90         if (addr_type == IPV6_ADDR_MAPPED) {
  91                 struct sockaddr_in sin;
  92
  93                 if (__ipv6_only_sock(sk)) {
  94                         err = -ENETUNREACH;
  95                         goto out;
  96                 }
  97                 sin.sin_family = AF_INET;
  98                 sin.sin_addr.s_addr = daddr->s6_addr32[3];
  99                 sin.sin_port = usin->sin6_port;
 100
 101                 err = ip4_datagram_connect(sk,
 102                                            (struct sockaddr *) &sin,
 103                                            sizeof(sin));
 104
 105 ipv4_connected:
 106                 if (err)
 107                         goto out;
 108
 109                 ipv6_addr_set_v4mapped(inet->inet_daddr, &sk->sk_v6_daddr);
 110
 111                 if (ipv6_addr_any(&np->saddr) ||
 112                     ipv6_mapped_addr_any(&np->saddr))
 113                         ipv6_addr_set_v4mapped(inet->inet_saddr, &np->saddr);
 114
 115                 if (ipv6_addr_any(&sk->sk_v6_rcv_saddr) ||
 116                     ipv6_mapped_addr_any(&sk->sk_v6_rcv_saddr)) {
 117                         ipv6_addr_set_v4mapped(inet->inet_rcv_saddr,
 118                                                &sk->sk_v6_rcv_saddr);
 119                         if (sk->sk_prot->rehash)
 120                                 sk->sk_prot->rehash(sk);
 121                 }
 122
 123                 goto out;
 124         }
 125
 126         if (__ipv6_addr_needs_scope_id(addr_type)) {
 127                 if (addr_len >= sizeof(struct sockaddr_in6) &&
 128                     usin->sin6_scope_id) {
 129                         if (sk->sk_bound_dev_if &&
 130                             sk->sk_bound_dev_if != usin->sin6_scope_id) {
 131                                 err = -EINVAL;
 132                                 goto out;
 133                         }
 134                         sk->sk_bound_dev_if = usin->sin6_scope_id;
 135                 }
 136
 137                 if (!sk->sk_bound_dev_if && (addr_type & IPV6_ADDR_MULTICAST))
 138                         sk->sk_bound_dev_if = np->mcast_oif;
 139
 140                 /* Connect to link-local address requires an interface */
 141                 if (!sk->sk_bound_dev_if) {
 142                         err = -EINVAL;
 143                         goto out;
 144                 }
 145         }
 146
 147         sk->sk_v6_daddr = *daddr;
 148         np->flow_label = fl6.flowlabel;
 149
 150         inet->inet_dport = usin->sin6_port;
 151
 152         /*
 153          *      Check for a route to destination an obtain the
 154          *      destination cache for it.
 155          */
 156
 157         fl6.flowi6_proto = sk->sk_protocol;
 158         fl6.daddr = sk->sk_v6_daddr;
 159         fl6.saddr = np->saddr;
 160         fl6.flowi6_oif = sk->sk_bound_dev_if;
 161         fl6.flowi6_mark = sk->sk_mark;
 162         fl6.fl6_dport = inet->inet_dport;
 163         fl6.fl6_sport = inet->inet_sport;
 164
 165         if (!fl6.flowi6_oif && (addr_type&IPV6_ADDR_MULTICAST))
 166                 fl6.flowi6_oif = np->mcast_oif;
 167
 168         security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
 169
 170         opt = flowlabel ? flowlabel->opt : np->opt;
 171         final_p = fl6_update_dst(&fl6, opt, &final);
 172
 173         dst = ip6_dst_lookup_flow(sk, &fl6, final_p);
 174         err = 0;
 175         if (IS_ERR(dst)) {
 176                 err = PTR_ERR(dst);
 177                 goto out;
 178         }
 179
 180         /* source address lookup done in ip6_dst_lookup */
 181
 182         if (ipv6_addr_any(&np->saddr))
 183                 np->saddr = fl6.saddr;
 184
 185         if (ipv6_addr_any(&sk->sk_v6_rcv_saddr)) {
 186                 sk->sk_v6_rcv_saddr = fl6.saddr;
 187                 inet->inet_rcv_saddr = LOOPBACK4_IPV6;
 188                 if (sk->sk_prot->rehash)
 189                         sk->sk_prot->rehash(sk);
 190         }
 191
 192         ip6_dst_store(sk, dst,
 193                       ipv6_addr_equal(&fl6.daddr, &sk->sk_v6_daddr) ?
 194                       &sk->sk_v6_daddr : NULL,
 195 #ifdef CONFIG_IPV6_SUBTREES
 196                       ipv6_addr_equal(&fl6.saddr, &np->saddr) ?
 197                       &np->saddr :
 198 #endif
 199                       NULL);
 200
 201         sk->sk_state = TCP_ESTABLISHED;
 202         ip6_set_txhash(sk);
 203 out:
 204         fl6_sock_release(flowlabel);
 205         return err;
 206 }
 207 EXPORT_SYMBOL_GPL(ip6_datagram_connect);
 208
 209 int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *uaddr,
 210                                  int addr_len)
 211 {
 212         DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, uaddr);
 213         if (sin6->sin6_family != AF_INET6)
 214                 return -EAFNOSUPPORT;
 215         return ip6_datagram_connect(sk, uaddr, addr_len);
 216 }
 217 EXPORT_SYMBOL_GPL(ip6_datagram_connect_v6_only);
 218
 219 void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
 220                      __be16 port, u32 info, u8 *payload)
 221 {
 222         struct ipv6_pinfo *np  = inet6_sk(sk);
 223         struct icmp6hdr *icmph = icmp6_hdr(skb);
 224         struct sock_exterr_skb *serr;
 225
 226         if (!np->recverr)
 227                 return;
 228
 229         skb = skb_clone(skb, GFP_ATOMIC);
 230         if (!skb)
 231                 return;
 232
 233         skb->protocol = htons(ETH_P_IPV6);
 234
 235         serr = SKB_EXT_ERR(skb);
 236         serr->ee.ee_errno = err;
 237         serr->ee.ee_origin = SO_EE_ORIGIN_ICMP6;
 238         serr->ee.ee_type = icmph->icmp6_type;
 239         serr->ee.ee_code = icmph->icmp6_code;
 240         serr->ee.ee_pad = 0;
 241         serr->ee.ee_info = info;
 242         serr->ee.ee_data = 0;
 243         serr->addr_offset = (u8 *)&(((struct ipv6hdr *)(icmph + 1))->daddr) -
 244                                   skb_network_header(skb);
 245         serr->port = port;
 246
 247         __skb_pull(skb, payload - skb->data);
 248         skb_reset_transport_header(skb);
 249
 250         if (sock_queue_err_skb(sk, skb))
 251                 kfree_skb(skb);
 252 }
 253
 254 void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info)
 255 {
 256         struct ipv6_pinfo *np = inet6_sk(sk);
 257         struct sock_exterr_skb *serr;
 258         struct ipv6hdr *iph;
 259         struct sk_buff *skb;
 260
 261         if (!np->recverr)
 262                 return;
 263
 264         skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
 265         if (!skb)
 266                 return;
 267
 268         skb->protocol = htons(ETH_P_IPV6);
 269
 270         skb_put(skb, sizeof(struct ipv6hdr));
 271         skb_reset_network_header(skb);
 272         iph = ipv6_hdr(skb);
 273         iph->daddr = fl6->daddr;
 274
 275         serr = SKB_EXT_ERR(skb);
 276         serr->ee.ee_errno = err;
 277         serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
 278         serr->ee.ee_type = 0;
 279         serr->ee.ee_code = 0;
 280         serr->ee.ee_pad = 0;
 281         serr->ee.ee_info = info;
 282         serr->ee.ee_data = 0;
 283         serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
 284         serr->port = fl6->fl6_dport;
 285
 286         __skb_pull(skb, skb_tail_pointer(skb) - skb->data);
 287         skb_reset_transport_header(skb);
 288
 289         if (sock_queue_err_skb(sk, skb))
 290                 kfree_skb(skb);
 291 }
 292
 293 void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu)
 294 {
 295         struct ipv6_pinfo *np = inet6_sk(sk);
 296         struct ipv6hdr *iph;
 297         struct sk_buff *skb;
 298         struct ip6_mtuinfo *mtu_info;
 299
 300         if (!np->rxopt.bits.rxpmtu)
 301                 return;
 302
 303         skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
 304         if (!skb)
 305                 return;
 306
 307         skb_put(skb, sizeof(struct ipv6hdr));
 308         skb_reset_network_header(skb);
 309         iph = ipv6_hdr(skb);
 310         iph->daddr = fl6->daddr;
 311
 312         mtu_info = IP6CBMTU(skb);
 313
 314         mtu_info->ip6m_mtu = mtu;
 315         mtu_info->ip6m_addr.sin6_family = AF_INET6;
 316         mtu_info->ip6m_addr.sin6_port = 0;
 317         mtu_info->ip6m_addr.sin6_flowinfo = 0;
 318         mtu_info->ip6m_addr.sin6_scope_id = fl6->flowi6_oif;
 319         mtu_info->ip6m_addr.sin6_addr = ipv6_hdr(skb)->daddr;
 320
 321         __skb_pull(skb, skb_tail_pointer(skb) - skb->data);
 322         skb_reset_transport_header(skb);
 323
 324         skb = xchg(&np->rxpmtu, skb);
 325         kfree_skb(skb);
 326 }
 327
 328 /*
 329  *      Handle MSG_ERRQUEUE
 330  */
 331 int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
 332 {
 333         struct ipv6_pinfo *np = inet6_sk(sk);
 334         struct sock_exterr_skb *serr;
 335         struct sk_buff *skb, *skb2;
 336         DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name);
 337         struct {
 338                 struct sock_extended_err ee;
 339                 struct sockaddr_in6      offender;
 340         } errhdr;
 341         int err;
 342         int copied;
 343
 344         err = -EAGAIN;
 345         skb = skb_dequeue(&sk->sk_error_queue);
 346         if (skb == NULL)
 347                 goto out;
 348
 349         copied = skb->len;
 350         if (copied > len) {
 351                 msg->msg_flags |= MSG_TRUNC;
 352                 copied = len;
 353         }
 354         err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
 355         if (err)
 356                 goto out_free_skb;
 357
 358         sock_recv_timestamp(msg, sk, skb);
 359
 360         serr = SKB_EXT_ERR(skb);
 361
 362         if (sin) {
 363                 const unsigned char *nh = skb_network_header(skb);
 364                 sin->sin6_family = AF_INET6;
 365                 sin->sin6_flowinfo = 0;
 366                 sin->sin6_port = serr->port;
 367                 if (skb->protocol == htons(ETH_P_IPV6)) {
 368                         const struct ipv6hdr *ip6h = container_of((struct in6_addr *)(nh + serr->addr_offset),
 369                                                                   struct ipv6hdr, daddr);
 370                         sin->sin6_addr = ip6h->daddr;
 371                         if (np->sndflow)
 372                                 sin->sin6_flowinfo = ip6_flowinfo(ip6h);
 373                         sin->sin6_scope_id =
 374                                 ipv6_iface_scope_id(&sin->sin6_addr,
 375                                                     IP6CB(skb)->iif);
 376                 } else {
 377                         ipv6_addr_set_v4mapped(*(__be32 *)(nh + serr->addr_offset),
 378                                                &sin->sin6_addr);
 379                         sin->sin6_scope_id = 0;
 380                 }
 381                 *addr_len = sizeof(*sin);
 382         }
 383
 384         memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
 385         sin = &errhdr.offender;
 386         sin->sin6_family = AF_UNSPEC;
 387         if (serr->ee.ee_origin != SO_EE_ORIGIN_LOCAL) {
 388                 sin->sin6_family = AF_INET6;
 389                 sin->sin6_flowinfo = 0;
 390                 sin->sin6_port = 0;
 391                 if (np->rxopt.all)
 392                         ip6_datagram_recv_common_ctl(sk, msg, skb);
 393                 if (skb->protocol == htons(ETH_P_IPV6)) {
 394                         sin->sin6_addr = ipv6_hdr(skb)->saddr;
 395                         if (np->rxopt.all)
 396                                 ip6_datagram_recv_specific_ctl(sk, msg, skb);
 397                         sin->sin6_scope_id =
 398                                 ipv6_iface_scope_id(&sin->sin6_addr,
 399                                                     IP6CB(skb)->iif);
 400                 } else {
 401                         struct inet_sock *inet = inet_sk(sk);
 402
 403                         ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
 404                                                &sin->sin6_addr);
 405                         sin->sin6_scope_id = 0;
 406                         if (inet->cmsg_flags)
 407                                 ip_cmsg_recv(msg, skb);
 408                 }
 409         }
 410
 411         put_cmsg(msg, SOL_IPV6, IPV6_RECVERR, sizeof(errhdr), &errhdr);
 412
 413         /* Now we could try to dump offended packet options */
 414
 415         msg->msg_flags |= MSG_ERRQUEUE;
 416         err = copied;
 417
 418         /* Reset and regenerate socket error */
 419         spin_lock_bh(&sk->sk_error_queue.lock);
 420         sk->sk_err = 0;
 421         if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
 422                 sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
 423                 spin_unlock_bh(&sk->sk_error_queue.lock);
 424                 sk->sk_error_report(sk);
 425         } else {
 426                 spin_unlock_bh(&sk->sk_error_queue.lock);
 427         }
 428
 429 out_free_skb:
 430         kfree_skb(skb);
 431 out:
 432         return err;
 433 }
 434 EXPORT_SYMBOL_GPL(ipv6_recv_error);
 435
 436 /*
 437  *      Handle IPV6_RECVPATHMTU
 438  */
 439 int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len,
 440                      int *addr_len)
 441 {
 442         struct ipv6_pinfo *np = inet6_sk(sk);
 443         struct sk_buff *skb;
 444         struct ip6_mtuinfo mtu_info;
 445         DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name);
 446         int err;
 447         int copied;
 448
 449         err = -EAGAIN;
 450         skb = xchg(&np->rxpmtu, NULL);
 451         if (skb == NULL)
 452                 goto out;
 453
 454         copied = skb->len;
 455         if (copied > len) {
 456                 msg->msg_flags |= MSG_TRUNC;
 457                 copied = len;
 458         }
 459         err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
 460         if (err)
 461                 goto out_free_skb;
 462
 463         sock_recv_timestamp(msg, sk, skb);
 464
 465         memcpy(&mtu_info, IP6CBMTU(skb), sizeof(mtu_info));
 466
 467         if (sin) {
 468                 sin->sin6_family = AF_INET6;
 469                 sin->sin6_flowinfo = 0;
 470                 sin->sin6_port = 0;
 471                 sin->sin6_scope_id = mtu_info.ip6m_addr.sin6_scope_id;
 472                 sin->sin6_addr = mtu_info.ip6m_addr.sin6_addr;
 473                 *addr_len = sizeof(*sin);
 474         }
 475
 476         put_cmsg(msg, SOL_IPV6, IPV6_PATHMTU, sizeof(mtu_info), &mtu_info);
 477
 478         err = copied;
 479
 480 out_free_skb:
 481         kfree_skb(skb);
 482 out:
 483         return err;
 484 }
 485
 486
 487 void ip6_datagram_recv_common_ctl(struct sock *sk, struct msghdr *msg,
 488                                  struct sk_buff *skb)
 489 {
 490         struct ipv6_pinfo *np = inet6_sk(sk);
 491         bool is_ipv6 = skb->protocol == htons(ETH_P_IPV6);
 492
 493         if (np->rxopt.bits.rxinfo) {
 494                 struct in6_pktinfo src_info;
 495
 496                 if (is_ipv6) {
 497                         src_info.ipi6_ifindex = IP6CB(skb)->iif;
 498                         src_info.ipi6_addr = ipv6_hdr(skb)->daddr;
 499                 } else {
 500                         src_info.ipi6_ifindex =
 501                                 PKTINFO_SKB_CB(skb)->ipi_ifindex;
 502                         ipv6_addr_set_v4mapped(ip_hdr(skb)->daddr,
 503                                                &src_info.ipi6_addr);
 504                 }
 505                 put_cmsg(msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info);
 506         }
 507 }
 508
 509 void ip6_datagram_recv_specific_ctl(struct sock *sk, struct msghdr *msg,
 510                                     struct sk_buff *skb)
 511 {
 512         struct ipv6_pinfo *np = inet6_sk(sk);
 513         struct inet6_skb_parm *opt = IP6CB(skb);
 514         unsigned char *nh = skb_network_header(skb);
 515
 516         if (np->rxopt.bits.rxhlim) {
 517                 int hlim = ipv6_hdr(skb)->hop_limit;
 518                 put_cmsg(msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
 519         }
 520
 521         if (np->rxopt.bits.rxtclass) {
 522                 int tclass = ipv6_get_dsfield(ipv6_hdr(skb));
 523                 put_cmsg(msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
 524         }
 525
 526         if (np->rxopt.bits.rxflow) {
 527                 __be32 flowinfo = ip6_flowinfo((struct ipv6hdr *)nh);
 528                 if (flowinfo)
 529                         put_cmsg(msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
 530         }
 531
 532         /* HbH is allowed only once */
 533         if (np->rxopt.bits.hopopts && opt->hop) {
 534                 u8 *ptr = nh + opt->hop;
 535                 put_cmsg(msg, SOL_IPV6, IPV6_HOPOPTS, (ptr[1]+1)<<3, ptr);
 536         }
 537
 538         if (opt->lastopt &&
 539             (np->rxopt.bits.dstopts || np->rxopt.bits.srcrt)) {
 540                 /*
 541                  * Silly enough, but we need to reparse in order to
 542                  * report extension headers (except for HbH)
 543                  * in order.
 544                  *
 545                  * Also note that IPV6_RECVRTHDRDSTOPTS is NOT
 546                  * (and WILL NOT be) defined because
 547                  * IPV6_RECVDSTOPTS is more generic. --yoshfuji
 548                  */
 549                 unsigned int off = sizeof(struct ipv6hdr);
 550                 u8 nexthdr = ipv6_hdr(skb)->nexthdr;
 551
 552                 while (off <= opt->lastopt) {
 553                         unsigned int len;
 554                         u8 *ptr = nh + off;
 555
 556                         switch (nexthdr) {
 557                         case IPPROTO_DSTOPTS:
 558                                 nexthdr = ptr[0];
 559                                 len = (ptr[1] + 1) << 3;
 560                                 if (np->rxopt.bits.dstopts)
 561                                         put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, len, ptr);
 562                                 break;
 563                         case IPPROTO_ROUTING:
 564                                 nexthdr = ptr[0];
 565                                 len = (ptr[1] + 1) << 3;
 566                                 if (np->rxopt.bits.srcrt)
 567                                         put_cmsg(msg, SOL_IPV6, IPV6_RTHDR, len, ptr);
 568                                 break;
 569                         case IPPROTO_AH:
 570                                 nexthdr = ptr[0];
 571                                 len = (ptr[1] + 2) << 2;
 572                                 break;
 573                         default:
 574                                 nexthdr = ptr[0];
 575                                 len = (ptr[1] + 1) << 3;
 576                                 break;
 577                         }
 578
 579                         off += len;
 580                 }
 581         }
 582
 583         /* socket options in old style */
 584         if (np->rxopt.bits.rxoinfo) {
 585                 struct in6_pktinfo src_info;
 586
 587                 src_info.ipi6_ifindex = opt->iif;
 588                 src_info.ipi6_addr = ipv6_hdr(skb)->daddr;
 589                 put_cmsg(msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
 590         }
 591         if (np->rxopt.bits.rxohlim) {
 592                 int hlim = ipv6_hdr(skb)->hop_limit;
 593                 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
 594         }
 595         if (np->rxopt.bits.ohopopts && opt->hop) {
 596                 u8 *ptr = nh + opt->hop;
 597                 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPOPTS, (ptr[1]+1)<<3, ptr);
 598         }
 599         if (np->rxopt.bits.odstopts && opt->dst0) {
 600                 u8 *ptr = nh + opt->dst0;
 601                 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
 602         }
 603         if (np->rxopt.bits.osrcrt && opt->srcrt) {
 604                 struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(nh + opt->srcrt);
 605                 put_cmsg(msg, SOL_IPV6, IPV6_2292RTHDR, (rthdr->hdrlen+1) << 3, rthdr);
 606         }
 607         if (np->rxopt.bits.odstopts && opt->dst1) {
 608                 u8 *ptr = nh + opt->dst1;
 609                 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
 610         }
 611         if (np->rxopt.bits.rxorigdstaddr) {
 612                 struct sockaddr_in6 sin6;
 613                 __be16 *ports = (__be16 *) skb_transport_header(skb);
 614
 615                 if (skb_transport_offset(skb) + 4 <= skb->len) {
 616                         /* All current transport protocols have the port numbers in the
 617                          * first four bytes of the transport header and this function is
 618                          * written with this assumption in mind.
 619                          */
 620
 621                         sin6.sin6_family = AF_INET6;
 622                         sin6.sin6_addr = ipv6_hdr(skb)->daddr;
 623                         sin6.sin6_port = ports[1];
 624                         sin6.sin6_flowinfo = 0;
 625                         sin6.sin6_scope_id =
 626                                 ipv6_iface_scope_id(&ipv6_hdr(skb)->daddr,
 627                                                     opt->iif);
 628
 629                         put_cmsg(msg, SOL_IPV6, IPV6_ORIGDSTADDR, sizeof(sin6), &sin6);
 630                 }
 631         }
 632 }
 633
 634 void ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg,
 635                           struct sk_buff *skb)
 636 {
 637         ip6_datagram_recv_common_ctl(sk, msg, skb);
 638         ip6_datagram_recv_specific_ctl(sk, msg, skb);
 639 }
 640 EXPORT_SYMBOL_GPL(ip6_datagram_recv_ctl);
 641
 642 int ip6_datagram_send_ctl(struct net *net, struct sock *sk,
 643                           struct msghdr *msg, struct flowi6 *fl6,
 644                           struct ipv6_txoptions *opt,
 645                           int *hlimit, int *tclass, int *dontfrag)
 646 {
 647         struct in6_pktinfo *src_info;
 648         struct cmsghdr *cmsg;
 649         struct ipv6_rt_hdr *rthdr;
 650         struct ipv6_opt_hdr *hdr;
 651         int len;
 652         int err = 0;
 653
 654         for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
 655                 int addr_type;
 656
 657                 if (!CMSG_OK(msg, cmsg)) {
 658                         err = -EINVAL;
 659                         goto exit_f;
 660                 }
 661
 662                 if (cmsg->cmsg_level != SOL_IPV6)
 663                         continue;
 664
 665                 switch (cmsg->cmsg_type) {
 666                 case IPV6_PKTINFO:
 667                 case IPV6_2292PKTINFO:
 668                     {
 669                         struct net_device *dev = NULL;
 670
 671                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct in6_pktinfo))) {
 672                                 err = -EINVAL;
 673                                 goto exit_f;
 674                         }
 675
 676                         src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
 677
 678                         if (src_info->ipi6_ifindex) {
 679                                 if (fl6->flowi6_oif &&
 680                                     src_info->ipi6_ifindex != fl6->flowi6_oif)
 681                                         return -EINVAL;
 682                                 fl6->flowi6_oif = src_info->ipi6_ifindex;
 683                         }
 684
 685                         addr_type = __ipv6_addr_type(&src_info->ipi6_addr);
 686
 687                         rcu_read_lock();
 688                         if (fl6->flowi6_oif) {
 689                                 dev = dev_get_by_index_rcu(net, fl6->flowi6_oif);
 690                                 if (!dev) {
 691                                         rcu_read_unlock();
 692                                         return -ENODEV;
 693                                 }
 694                         } else if (addr_type & IPV6_ADDR_LINKLOCAL) {
 695                                 rcu_read_unlock();
 696                                 return -EINVAL;
 697                         }
 698
 699                         if (addr_type != IPV6_ADDR_ANY) {
 700                                 int strict = __ipv6_addr_src_scope(addr_type) <= IPV6_ADDR_SCOPE_LINKLOCAL;
 701                                 if (!(inet_sk(sk)->freebind || inet_sk(sk)->transparent) &&
 702                                     !ipv6_chk_addr(net, &src_info->ipi6_addr,
 703                                                    strict ? dev : NULL, 0) &&
 704                                     !ipv6_chk_acast_addr_src(net, dev,
 705                                                              &src_info->ipi6_addr))
 706                                         err = -EINVAL;
 707                                 else
 708                                         fl6->saddr = src_info->ipi6_addr;
 709                         }
 710
 711                         rcu_read_unlock();
 712
 713                         if (err)
 714                                 goto exit_f;
 715
 716                         break;
 717                     }
 718
 719                 case IPV6_FLOWINFO:
 720                         if (cmsg->cmsg_len < CMSG_LEN(4)) {
 721                                 err = -EINVAL;
 722                                 goto exit_f;
 723                         }
 724
 725                         if (fl6->flowlabel&IPV6_FLOWINFO_MASK) {
 726                                 if ((fl6->flowlabel^*(__be32 *)CMSG_DATA(cmsg))&~IPV6_FLOWINFO_MASK) {
 727                                         err = -EINVAL;
 728                                         goto exit_f;
 729                                 }
 730                         }
 731                         fl6->flowlabel = IPV6_FLOWINFO_MASK & *(__be32 *)CMSG_DATA(cmsg);
 732                         break;
 733
 734                 case IPV6_2292HOPOPTS:
 735                 case IPV6_HOPOPTS:
 736                         if (opt->hopopt || cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
 737                                 err = -EINVAL;
 738                                 goto exit_f;
 739                         }
 740
 741                         hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
 742                         len = ((hdr->hdrlen + 1) << 3);
 743                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
 744                                 err = -EINVAL;
 745                                 goto exit_f;
 746                         }
 747                         if (!ns_capable(net->user_ns, CAP_NET_RAW)) {
 748                                 err = -EPERM;
 749                                 goto exit_f;
 750                         }
 751                         opt->opt_nflen += len;
 752                         opt->hopopt = hdr;
 753                         break;
 754
 755                 case IPV6_2292DSTOPTS:
 756                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
 757                                 err = -EINVAL;
 758                                 goto exit_f;
 759                         }
 760
 761                         hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
 762                         len = ((hdr->hdrlen + 1) << 3);
 763                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
 764                                 err = -EINVAL;
 765                                 goto exit_f;
 766                         }
 767                         if (!ns_capable(net->user_ns, CAP_NET_RAW)) {
 768                                 err = -EPERM;
 769                                 goto exit_f;
 770                         }
 771                         if (opt->dst1opt) {
 772                                 err = -EINVAL;
 773                                 goto exit_f;
 774                         }
 775                         opt->opt_flen += len;
 776                         opt->dst1opt = hdr;
 777                         break;
 778
 779                 case IPV6_DSTOPTS:
 780                 case IPV6_RTHDRDSTOPTS:
 781                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
 782                                 err = -EINVAL;
 783                                 goto exit_f;
 784                         }
 785
 786                         hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
 787                         len = ((hdr->hdrlen + 1) << 3);
 788                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
 789                                 err = -EINVAL;
 790                                 goto exit_f;
 791                         }
 792                         if (!ns_capable(net->user_ns, CAP_NET_RAW)) {
 793                                 err = -EPERM;
 794                                 goto exit_f;
 795                         }
 796                         if (cmsg->cmsg_type == IPV6_DSTOPTS) {
 797                                 opt->opt_flen += len;
 798                                 opt->dst1opt = hdr;
 799                         } else {
 800                                 opt->opt_nflen += len;
 801                                 opt->dst0opt = hdr;
 802                         }
 803                         break;
 804
 805                 case IPV6_2292RTHDR:
 806                 case IPV6_RTHDR:
 807                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_rt_hdr))) {
 808                                 err = -EINVAL;
 809                                 goto exit_f;
 810                         }
 811
 812                         rthdr = (struct ipv6_rt_hdr *)CMSG_DATA(cmsg);
 813
 814                         switch (rthdr->type) {
 815 #if IS_ENABLED(CONFIG_IPV6_MIP6)
 816                         case IPV6_SRCRT_TYPE_2:
 817                                 if (rthdr->hdrlen != 2 ||
 818                                     rthdr->segments_left != 1) {
 819                                         err = -EINVAL;
 820                                         goto exit_f;
 821                                 }
 822                                 break;
 823 #endif
 824                         default:
 825                                 err = -EINVAL;
 826                                 goto exit_f;
 827                         }
 828
 829                         len = ((rthdr->hdrlen + 1) << 3);
 830
 831                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
 832                                 err = -EINVAL;
 833                                 goto exit_f;
 834                         }
 835
 836                         /* segments left must also match */
 837                         if ((rthdr->hdrlen >> 1) != rthdr->segments_left) {
 838                                 err = -EINVAL;
 839                                 goto exit_f;
 840                         }
 841
 842                         opt->opt_nflen += len;
 843                         opt->srcrt = rthdr;
 844
 845                         if (cmsg->cmsg_type == IPV6_2292RTHDR && opt->dst1opt) {
 846                                 int dsthdrlen = ((opt->dst1opt->hdrlen+1)<<3);
 847
 848                                 opt->opt_nflen += dsthdrlen;
 849                                 opt->dst0opt = opt->dst1opt;
 850                                 opt->dst1opt = NULL;
 851                                 opt->opt_flen -= dsthdrlen;
 852                         }
 853
 854                         break;
 855
 856                 case IPV6_2292HOPLIMIT:
 857                 case IPV6_HOPLIMIT:
 858                         if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
 859                                 err = -EINVAL;
 860                                 goto exit_f;
 861                         }
 862
 863                         *hlimit = *(int *)CMSG_DATA(cmsg);
 864                         if (*hlimit < -1 || *hlimit > 0xff) {
 865                                 err = -EINVAL;
 866                                 goto exit_f;
 867                         }
 868
 869                         break;
 870
 871                 case IPV6_TCLASS:
 872                     {
 873                         int tc;
 874
 875                         err = -EINVAL;
 876                         if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
 877                                 goto exit_f;
 878
 879                         tc = *(int *)CMSG_DATA(cmsg);
 880                         if (tc < -1 || tc > 0xff)
 881                                 goto exit_f;
 882
 883                         err = 0;
 884                         *tclass = tc;
 885
 886                         break;
 887                     }
 888
 889                 case IPV6_DONTFRAG:
 890                     {
 891                         int df;
 892
 893                         err = -EINVAL;
 894                         if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
 895                                 goto exit_f;
 896
 897                         df = *(int *)CMSG_DATA(cmsg);
 898                         if (df < 0 || df > 1)
 899                                 goto exit_f;
 900
 901                         err = 0;
 902                         *dontfrag = df;
 903
 904                         break;
 905                     }
 906                 default:
 907                         LIMIT_NETDEBUG(KERN_DEBUG "invalid cmsg type: %d\n",
 908                                        cmsg->cmsg_type);
 909                         err = -EINVAL;
 910                         goto exit_f;
 911                 }
 912         }
 913
 914 exit_f:
 915         return err;
 916 }
 917 EXPORT_SYMBOL_GPL(ip6_datagram_send_ctl);
 918
 919 void ip6_dgram_sock_seq_show(struct seq_file *seq, struct sock *sp,
 920                              __u16 srcp, __u16 destp, int bucket)
 921 {
 922         const struct in6_addr *dest, *src;
 923
 924         dest  = &sp->sk_v6_daddr;
 925         src   = &sp->sk_v6_rcv_saddr;
 926         seq_printf(seq,
 927                    "%5d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
 928                    "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %d\n",
 929                    bucket,
 930                    src->s6_addr32[0], src->s6_addr32[1],
 931                    src->s6_addr32[2], src->s6_addr32[3], srcp,
 932                    dest->s6_addr32[0], dest->s6_addr32[1],
 933                    dest->s6_addr32[2], dest->s6_addr32[3], destp,
 934                    sp->sk_state,
 935                    sk_wmem_alloc_get(sp),
 936                    sk_rmem_alloc_get(sp),
 937                    0, 0L, 0,
 938                    from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)),
 939                    0,
 940                    sock_i_ino(sp),
 941                    atomic_read(&sp->sk_refcnt), sp,
 942                    atomic_read(&sp->sk_drops));
 943 }