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 static void ip6_datagram_prepare_pktinfo_errqueue(struct sk_buff *skb)
 329 {
 330         int ifindex = skb->dev ? skb->dev->ifindex : -1;
 331
 332         if (skb->protocol == htons(ETH_P_IPV6))
 333                 IP6CB(skb)->iif = ifindex;
 334         else
 335                 PKTINFO_SKB_CB(skb)->ipi_ifindex = ifindex;
 336 }
 337
 338 /*
 339  *      Handle MSG_ERRQUEUE
 340  */
 341 int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
 342 {
 343         struct ipv6_pinfo *np = inet6_sk(sk);
 344         struct sock_exterr_skb *serr;
 345         struct sk_buff *skb;
 346         DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name);
 347         struct {
 348                 struct sock_extended_err ee;
 349                 struct sockaddr_in6      offender;
 350         } errhdr;
 351         int err;
 352         int copied;
 353
 354         err = -EAGAIN;
 355         skb = sock_dequeue_err_skb(sk);
 356         if (skb == NULL)
 357                 goto out;
 358
 359         copied = skb->len;
 360         if (copied > len) {
 361                 msg->msg_flags |= MSG_TRUNC;
 362                 copied = len;
 363         }
 364         err = skb_copy_datagram_msg(skb, 0, msg, copied);
 365         if (err)
 366                 goto out_free_skb;
 367
 368         sock_recv_timestamp(msg, sk, skb);
 369
 370         serr = SKB_EXT_ERR(skb);
 371
 372         if (sin) {
 373                 const unsigned char *nh = skb_network_header(skb);
 374                 sin->sin6_family = AF_INET6;
 375                 sin->sin6_flowinfo = 0;
 376                 sin->sin6_port = serr->port;
 377                 if (skb->protocol == htons(ETH_P_IPV6)) {
 378                         const struct ipv6hdr *ip6h = container_of((struct in6_addr *)(nh + serr->addr_offset),
 379                                                                   struct ipv6hdr, daddr);
 380                         sin->sin6_addr = ip6h->daddr;
 381                         if (np->sndflow)
 382                                 sin->sin6_flowinfo = ip6_flowinfo(ip6h);
 383                         sin->sin6_scope_id =
 384                                 ipv6_iface_scope_id(&sin->sin6_addr,
 385                                                     IP6CB(skb)->iif);
 386                 } else {
 387                         ipv6_addr_set_v4mapped(*(__be32 *)(nh + serr->addr_offset),
 388                                                &sin->sin6_addr);
 389                         sin->sin6_scope_id = 0;
 390                 }
 391                 *addr_len = sizeof(*sin);
 392         }
 393
 394         memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
 395         sin = &errhdr.offender;
 396         memset(sin, 0, sizeof(*sin));
 397
 398         if (serr->ee.ee_origin != SO_EE_ORIGIN_LOCAL) {
 399                 sin->sin6_family = AF_INET6;
 400                 if (np->rxopt.all) {
 401                         if (serr->ee.ee_origin != SO_EE_ORIGIN_ICMP &&
 402                             serr->ee.ee_origin != SO_EE_ORIGIN_ICMP6)
 403                                 ip6_datagram_prepare_pktinfo_errqueue(skb);
 404                         ip6_datagram_recv_common_ctl(sk, msg, skb);
 405                 }
 406                 if (skb->protocol == htons(ETH_P_IPV6)) {
 407                         sin->sin6_addr = ipv6_hdr(skb)->saddr;
 408                         if (np->rxopt.all)
 409                                 ip6_datagram_recv_specific_ctl(sk, msg, skb);
 410                         sin->sin6_scope_id =
 411                                 ipv6_iface_scope_id(&sin->sin6_addr,
 412                                                     IP6CB(skb)->iif);
 413                 } else {
 414                         ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
 415                                                &sin->sin6_addr);
 416                         if (inet_sk(sk)->cmsg_flags)
 417                                 ip_cmsg_recv(msg, skb);
 418                 }
 419         }
 420
 421         put_cmsg(msg, SOL_IPV6, IPV6_RECVERR, sizeof(errhdr), &errhdr);
 422
 423         /* Now we could try to dump offended packet options */
 424
 425         msg->msg_flags |= MSG_ERRQUEUE;
 426         err = copied;
 427
 428 out_free_skb:
 429         kfree_skb(skb);
 430 out:
 431         return err;
 432 }
 433 EXPORT_SYMBOL_GPL(ipv6_recv_error);
 434
 435 /*
 436  *      Handle IPV6_RECVPATHMTU
 437  */
 438 int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len,
 439                      int *addr_len)
 440 {
 441         struct ipv6_pinfo *np = inet6_sk(sk);
 442         struct sk_buff *skb;
 443         struct ip6_mtuinfo mtu_info;
 444         DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name);
 445         int err;
 446         int copied;
 447
 448         err = -EAGAIN;
 449         skb = xchg(&np->rxpmtu, NULL);
 450         if (skb == NULL)
 451                 goto out;
 452
 453         copied = skb->len;
 454         if (copied > len) {
 455                 msg->msg_flags |= MSG_TRUNC;
 456                 copied = len;
 457         }
 458         err = skb_copy_datagram_msg(skb, 0, msg, copied);
 459         if (err)
 460                 goto out_free_skb;
 461
 462         sock_recv_timestamp(msg, sk, skb);
 463
 464         memcpy(&mtu_info, IP6CBMTU(skb), sizeof(mtu_info));
 465
 466         if (sin) {
 467                 sin->sin6_family = AF_INET6;
 468                 sin->sin6_flowinfo = 0;
 469                 sin->sin6_port = 0;
 470                 sin->sin6_scope_id = mtu_info.ip6m_addr.sin6_scope_id;
 471                 sin->sin6_addr = mtu_info.ip6m_addr.sin6_addr;
 472                 *addr_len = sizeof(*sin);
 473         }
 474
 475         put_cmsg(msg, SOL_IPV6, IPV6_PATHMTU, sizeof(mtu_info), &mtu_info);
 476
 477         err = copied;
 478
 479 out_free_skb:
 480         kfree_skb(skb);
 481 out:
 482         return err;
 483 }
 484
 485
 486 void ip6_datagram_recv_common_ctl(struct sock *sk, struct msghdr *msg,
 487                                  struct sk_buff *skb)
 488 {
 489         struct ipv6_pinfo *np = inet6_sk(sk);
 490         bool is_ipv6 = skb->protocol == htons(ETH_P_IPV6);
 491
 492         if (np->rxopt.bits.rxinfo) {
 493                 struct in6_pktinfo src_info;
 494
 495                 if (is_ipv6) {
 496                         src_info.ipi6_ifindex = IP6CB(skb)->iif;
 497                         src_info.ipi6_addr = ipv6_hdr(skb)->daddr;
 498                 } else {
 499                         src_info.ipi6_ifindex =
 500                                 PKTINFO_SKB_CB(skb)->ipi_ifindex;
 501                         ipv6_addr_set_v4mapped(ip_hdr(skb)->daddr,
 502                                                &src_info.ipi6_addr);
 503                 }
 504
 505                 if (src_info.ipi6_ifindex >= 0)
 506                         put_cmsg(msg, SOL_IPV6, IPV6_PKTINFO,
 507                                  sizeof(src_info), &src_info);
 508         }
 509 }
 510
 511 void ip6_datagram_recv_specific_ctl(struct sock *sk, struct msghdr *msg,
 512                                     struct sk_buff *skb)
 513 {
 514         struct ipv6_pinfo *np = inet6_sk(sk);
 515         struct inet6_skb_parm *opt = IP6CB(skb);
 516         unsigned char *nh = skb_network_header(skb);
 517
 518         if (np->rxopt.bits.rxhlim) {
 519                 int hlim = ipv6_hdr(skb)->hop_limit;
 520                 put_cmsg(msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
 521         }
 522
 523         if (np->rxopt.bits.rxtclass) {
 524                 int tclass = ipv6_get_dsfield(ipv6_hdr(skb));
 525                 put_cmsg(msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
 526         }
 527
 528         if (np->rxopt.bits.rxflow) {
 529                 __be32 flowinfo = ip6_flowinfo((struct ipv6hdr *)nh);
 530                 if (flowinfo)
 531                         put_cmsg(msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
 532         }
 533
 534         /* HbH is allowed only once */
 535         if (np->rxopt.bits.hopopts && opt->hop) {
 536                 u8 *ptr = nh + opt->hop;
 537                 put_cmsg(msg, SOL_IPV6, IPV6_HOPOPTS, (ptr[1]+1)<<3, ptr);
 538         }
 539
 540         if (opt->lastopt &&
 541             (np->rxopt.bits.dstopts || np->rxopt.bits.srcrt)) {
 542                 /*
 543                  * Silly enough, but we need to reparse in order to
 544                  * report extension headers (except for HbH)
 545                  * in order.
 546                  *
 547                  * Also note that IPV6_RECVRTHDRDSTOPTS is NOT
 548                  * (and WILL NOT be) defined because
 549                  * IPV6_RECVDSTOPTS is more generic. --yoshfuji
 550                  */
 551                 unsigned int off = sizeof(struct ipv6hdr);
 552                 u8 nexthdr = ipv6_hdr(skb)->nexthdr;
 553
 554                 while (off <= opt->lastopt) {
 555                         unsigned int len;
 556                         u8 *ptr = nh + off;
 557
 558                         switch (nexthdr) {
 559                         case IPPROTO_DSTOPTS:
 560                                 nexthdr = ptr[0];
 561                                 len = (ptr[1] + 1) << 3;
 562                                 if (np->rxopt.bits.dstopts)
 563                                         put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, len, ptr);
 564                                 break;
 565                         case IPPROTO_ROUTING:
 566                                 nexthdr = ptr[0];
 567                                 len = (ptr[1] + 1) << 3;
 568                                 if (np->rxopt.bits.srcrt)
 569                                         put_cmsg(msg, SOL_IPV6, IPV6_RTHDR, len, ptr);
 570                                 break;
 571                         case IPPROTO_AH:
 572                                 nexthdr = ptr[0];
 573                                 len = (ptr[1] + 2) << 2;
 574                                 break;
 575                         default:
 576                                 nexthdr = ptr[0];
 577                                 len = (ptr[1] + 1) << 3;
 578                                 break;
 579                         }
 580
 581                         off += len;
 582                 }
 583         }
 584
 585         /* socket options in old style */
 586         if (np->rxopt.bits.rxoinfo) {
 587                 struct in6_pktinfo src_info;
 588
 589                 src_info.ipi6_ifindex = opt->iif;
 590                 src_info.ipi6_addr = ipv6_hdr(skb)->daddr;
 591                 put_cmsg(msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
 592         }
 593         if (np->rxopt.bits.rxohlim) {
 594                 int hlim = ipv6_hdr(skb)->hop_limit;
 595                 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
 596         }
 597         if (np->rxopt.bits.ohopopts && opt->hop) {
 598                 u8 *ptr = nh + opt->hop;
 599                 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPOPTS, (ptr[1]+1)<<3, ptr);
 600         }
 601         if (np->rxopt.bits.odstopts && opt->dst0) {
 602                 u8 *ptr = nh + opt->dst0;
 603                 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
 604         }
 605         if (np->rxopt.bits.osrcrt && opt->srcrt) {
 606                 struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(nh + opt->srcrt);
 607                 put_cmsg(msg, SOL_IPV6, IPV6_2292RTHDR, (rthdr->hdrlen+1) << 3, rthdr);
 608         }
 609         if (np->rxopt.bits.odstopts && opt->dst1) {
 610                 u8 *ptr = nh + opt->dst1;
 611                 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
 612         }
 613         if (np->rxopt.bits.rxorigdstaddr) {
 614                 struct sockaddr_in6 sin6;
 615                 __be16 *ports = (__be16 *) skb_transport_header(skb);
 616
 617                 if (skb_transport_offset(skb) + 4 <= skb->len) {
 618                         /* All current transport protocols have the port numbers in the
 619                          * first four bytes of the transport header and this function is
 620                          * written with this assumption in mind.
 621                          */
 622
 623                         sin6.sin6_family = AF_INET6;
 624                         sin6.sin6_addr = ipv6_hdr(skb)->daddr;
 625                         sin6.sin6_port = ports[1];
 626                         sin6.sin6_flowinfo = 0;
 627                         sin6.sin6_scope_id =
 628                                 ipv6_iface_scope_id(&ipv6_hdr(skb)->daddr,
 629                                                     opt->iif);
 630
 631                         put_cmsg(msg, SOL_IPV6, IPV6_ORIGDSTADDR, sizeof(sin6), &sin6);
 632                 }
 633         }
 634 }
 635
 636 void ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg,
 637                           struct sk_buff *skb)
 638 {
 639         ip6_datagram_recv_common_ctl(sk, msg, skb);
 640         ip6_datagram_recv_specific_ctl(sk, msg, skb);
 641 }
 642 EXPORT_SYMBOL_GPL(ip6_datagram_recv_ctl);
 643
 644 int ip6_datagram_send_ctl(struct net *net, struct sock *sk,
 645                           struct msghdr *msg, struct flowi6 *fl6,
 646                           struct ipv6_txoptions *opt,
 647                           int *hlimit, int *tclass, int *dontfrag)
 648 {
 649         struct in6_pktinfo *src_info;
 650         struct cmsghdr *cmsg;
 651         struct ipv6_rt_hdr *rthdr;
 652         struct ipv6_opt_hdr *hdr;
 653         int len;
 654         int err = 0;
 655
 656         for_each_cmsghdr(cmsg, msg) {
 657                 int addr_type;
 658
 659                 if (!CMSG_OK(msg, cmsg)) {
 660                         err = -EINVAL;
 661                         goto exit_f;
 662                 }
 663
 664                 if (cmsg->cmsg_level != SOL_IPV6)
 665                         continue;
 666
 667                 switch (cmsg->cmsg_type) {
 668                 case IPV6_PKTINFO:
 669                 case IPV6_2292PKTINFO:
 670                     {
 671                         struct net_device *dev = NULL;
 672
 673                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct in6_pktinfo))) {
 674                                 err = -EINVAL;
 675                                 goto exit_f;
 676                         }
 677
 678                         src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
 679
 680                         if (src_info->ipi6_ifindex) {
 681                                 if (fl6->flowi6_oif &&
 682                                     src_info->ipi6_ifindex != fl6->flowi6_oif)
 683                                         return -EINVAL;
 684                                 fl6->flowi6_oif = src_info->ipi6_ifindex;
 685                         }
 686
 687                         addr_type = __ipv6_addr_type(&src_info->ipi6_addr);
 688
 689                         rcu_read_lock();
 690                         if (fl6->flowi6_oif) {
 691                                 dev = dev_get_by_index_rcu(net, fl6->flowi6_oif);
 692                                 if (!dev) {
 693                                         rcu_read_unlock();
 694                                         return -ENODEV;
 695                                 }
 696                         } else if (addr_type & IPV6_ADDR_LINKLOCAL) {
 697                                 rcu_read_unlock();
 698                                 return -EINVAL;
 699                         }
 700
 701                         if (addr_type != IPV6_ADDR_ANY) {
 702                                 int strict = __ipv6_addr_src_scope(addr_type) <= IPV6_ADDR_SCOPE_LINKLOCAL;
 703                                 if (!(inet_sk(sk)->freebind || inet_sk(sk)->transparent) &&
 704                                     !ipv6_chk_addr(net, &src_info->ipi6_addr,
 705                                                    strict ? dev : NULL, 0) &&
 706                                     !ipv6_chk_acast_addr_src(net, dev,
 707                                                              &src_info->ipi6_addr))
 708                                         err = -EINVAL;
 709                                 else
 710                                         fl6->saddr = src_info->ipi6_addr;
 711                         }
 712
 713                         rcu_read_unlock();
 714
 715                         if (err)
 716                                 goto exit_f;
 717
 718                         break;
 719                     }
 720
 721                 case IPV6_FLOWINFO:
 722                         if (cmsg->cmsg_len < CMSG_LEN(4)) {
 723                                 err = -EINVAL;
 724                                 goto exit_f;
 725                         }
 726
 727                         if (fl6->flowlabel&IPV6_FLOWINFO_MASK) {
 728                                 if ((fl6->flowlabel^*(__be32 *)CMSG_DATA(cmsg))&~IPV6_FLOWINFO_MASK) {
 729                                         err = -EINVAL;
 730                                         goto exit_f;
 731                                 }
 732                         }
 733                         fl6->flowlabel = IPV6_FLOWINFO_MASK & *(__be32 *)CMSG_DATA(cmsg);
 734                         break;
 735
 736                 case IPV6_2292HOPOPTS:
 737                 case IPV6_HOPOPTS:
 738                         if (opt->hopopt || cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
 739                                 err = -EINVAL;
 740                                 goto exit_f;
 741                         }
 742
 743                         hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
 744                         len = ((hdr->hdrlen + 1) << 3);
 745                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
 746                                 err = -EINVAL;
 747                                 goto exit_f;
 748                         }
 749                         if (!ns_capable(net->user_ns, CAP_NET_RAW)) {
 750                                 err = -EPERM;
 751                                 goto exit_f;
 752                         }
 753                         opt->opt_nflen += len;
 754                         opt->hopopt = hdr;
 755                         break;
 756
 757                 case IPV6_2292DSTOPTS:
 758                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
 759                                 err = -EINVAL;
 760                                 goto exit_f;
 761                         }
 762
 763                         hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
 764                         len = ((hdr->hdrlen + 1) << 3);
 765                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
 766                                 err = -EINVAL;
 767                                 goto exit_f;
 768                         }
 769                         if (!ns_capable(net->user_ns, CAP_NET_RAW)) {
 770                                 err = -EPERM;
 771                                 goto exit_f;
 772                         }
 773                         if (opt->dst1opt) {
 774                                 err = -EINVAL;
 775                                 goto exit_f;
 776                         }
 777                         opt->opt_flen += len;
 778                         opt->dst1opt = hdr;
 779                         break;
 780
 781                 case IPV6_DSTOPTS:
 782                 case IPV6_RTHDRDSTOPTS:
 783                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
 784                                 err = -EINVAL;
 785                                 goto exit_f;
 786                         }
 787
 788                         hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
 789                         len = ((hdr->hdrlen + 1) << 3);
 790                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
 791                                 err = -EINVAL;
 792                                 goto exit_f;
 793                         }
 794                         if (!ns_capable(net->user_ns, CAP_NET_RAW)) {
 795                                 err = -EPERM;
 796                                 goto exit_f;
 797                         }
 798                         if (cmsg->cmsg_type == IPV6_DSTOPTS) {
 799                                 opt->opt_flen += len;
 800                                 opt->dst1opt = hdr;
 801                         } else {
 802                                 opt->opt_nflen += len;
 803                                 opt->dst0opt = hdr;
 804                         }
 805                         break;
 806
 807                 case IPV6_2292RTHDR:
 808                 case IPV6_RTHDR:
 809                         if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_rt_hdr))) {
 810                                 err = -EINVAL;
 811                                 goto exit_f;
 812                         }
 813
 814                         rthdr = (struct ipv6_rt_hdr *)CMSG_DATA(cmsg);
 815
 816                         switch (rthdr->type) {
 817 #if IS_ENABLED(CONFIG_IPV6_MIP6)
 818                         case IPV6_SRCRT_TYPE_2:
 819                                 if (rthdr->hdrlen != 2 ||
 820                                     rthdr->segments_left != 1) {
 821                                         err = -EINVAL;
 822                                         goto exit_f;
 823                                 }
 824                                 break;
 825 #endif
 826                         default:
 827                                 err = -EINVAL;
 828                                 goto exit_f;
 829                         }
 830
 831                         len = ((rthdr->hdrlen + 1) << 3);
 832
 833                         if (cmsg->cmsg_len < CMSG_LEN(len)) {
 834                                 err = -EINVAL;
 835                                 goto exit_f;
 836                         }
 837
 838                         /* segments left must also match */
 839                         if ((rthdr->hdrlen >> 1) != rthdr->segments_left) {
 840                                 err = -EINVAL;
 841                                 goto exit_f;
 842                         }
 843
 844                         opt->opt_nflen += len;
 845                         opt->srcrt = rthdr;
 846
 847                         if (cmsg->cmsg_type == IPV6_2292RTHDR && opt->dst1opt) {
 848                                 int dsthdrlen = ((opt->dst1opt->hdrlen+1)<<3);
 849
 850                                 opt->opt_nflen += dsthdrlen;
 851                                 opt->dst0opt = opt->dst1opt;
 852                                 opt->dst1opt = NULL;
 853                                 opt->opt_flen -= dsthdrlen;
 854                         }
 855
 856                         break;
 857
 858                 case IPV6_2292HOPLIMIT:
 859                 case IPV6_HOPLIMIT:
 860                         if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
 861                                 err = -EINVAL;
 862                                 goto exit_f;
 863                         }
 864
 865                         *hlimit = *(int *)CMSG_DATA(cmsg);
 866                         if (*hlimit < -1 || *hlimit > 0xff) {
 867                                 err = -EINVAL;
 868                                 goto exit_f;
 869                         }
 870
 871                         break;
 872
 873                 case IPV6_TCLASS:
 874                     {
 875                         int tc;
 876
 877                         err = -EINVAL;
 878                         if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
 879                                 goto exit_f;
 880
 881                         tc = *(int *)CMSG_DATA(cmsg);
 882                         if (tc < -1 || tc > 0xff)
 883                                 goto exit_f;
 884
 885                         err = 0;
 886                         *tclass = tc;
 887
 888                         break;
 889                     }
 890
 891                 case IPV6_DONTFRAG:
 892                     {
 893                         int df;
 894
 895                         err = -EINVAL;
 896                         if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
 897                                 goto exit_f;
 898
 899                         df = *(int *)CMSG_DATA(cmsg);
 900                         if (df < 0 || df > 1)
 901                                 goto exit_f;
 902
 903                         err = 0;
 904                         *dontfrag = df;
 905
 906                         break;
 907                     }
 908                 default:
 909                         net_dbg_ratelimited("invalid cmsg type: %d\n",
 910                                             cmsg->cmsg_type);
 911                         err = -EINVAL;
 912                         goto exit_f;
 913                 }
 914         }
 915
 916 exit_f:
 917         return err;
 918 }
 919 EXPORT_SYMBOL_GPL(ip6_datagram_send_ctl);
 920
 921 void ip6_dgram_sock_seq_show(struct seq_file *seq, struct sock *sp,
 922                              __u16 srcp, __u16 destp, int bucket)
 923 {
 924         const struct in6_addr *dest, *src;
 925
 926         dest  = &sp->sk_v6_daddr;
 927         src   = &sp->sk_v6_rcv_saddr;
 928         seq_printf(seq,
 929                    "%5d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
 930                    "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %d\n",
 931                    bucket,
 932                    src->s6_addr32[0], src->s6_addr32[1],
 933                    src->s6_addr32[2], src->s6_addr32[3], srcp,
 934                    dest->s6_addr32[0], dest->s6_addr32[1],
 935                    dest->s6_addr32[2], dest->s6_addr32[3], destp,
 936                    sp->sk_state,
 937                    sk_wmem_alloc_get(sp),
 938                    sk_rmem_alloc_get(sp),
 939                    0, 0L, 0,
 940                    from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)),
 941                    0,
 942                    sock_i_ino(sp),
 943                    atomic_read(&sp->sk_refcnt), sp,
 944                    atomic_read(&sp->sk_drops));
 945 }