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 <linux/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 static void ip6_datagram_flow_key_init(struct flowi6 *fl6, struct sock *sk) 44 { 45 struct inet_sock *inet = inet_sk(sk); 46 struct ipv6_pinfo *np = inet6_sk(sk); 47 48 memset(fl6, 0, sizeof(*fl6)); 49 fl6->flowi6_proto = sk->sk_protocol; 50 fl6->daddr = sk->sk_v6_daddr; 51 fl6->saddr = np->saddr; 52 fl6->flowi6_oif = sk->sk_bound_dev_if; 53 fl6->flowi6_mark = sk->sk_mark; 54 fl6->fl6_dport = inet->inet_dport; 55 fl6->fl6_sport = inet->inet_sport; 56 fl6->flowlabel = np->flow_label; 57 fl6->flowi6_uid = sk->sk_uid; 58 59 if (!fl6->flowi6_oif) 60 fl6->flowi6_oif = np->sticky_pktinfo.ipi6_ifindex; 61 62 if (!fl6->flowi6_oif && ipv6_addr_is_multicast(&fl6->daddr)) 63 fl6->flowi6_oif = np->mcast_oif; 64 65 security_sk_classify_flow(sk, flowi6_to_flowi(fl6)); 66 } 67 68 int ip6_datagram_dst_update(struct sock *sk, bool fix_sk_saddr) 69 { 70 struct ip6_flowlabel *flowlabel = NULL; 71 struct in6_addr *final_p, final; 72 struct ipv6_txoptions *opt; 73 struct dst_entry *dst; 74 struct inet_sock *inet = inet_sk(sk); 75 struct ipv6_pinfo *np = inet6_sk(sk); 76 struct flowi6 fl6; 77 int err = 0; 78 79 if (np->sndflow && (np->flow_label & IPV6_FLOWLABEL_MASK)) { 80 flowlabel = fl6_sock_lookup(sk, np->flow_label); 81 if (!flowlabel) 82 return -EINVAL; 83 } 84 ip6_datagram_flow_key_init(&fl6, sk); 85 86 rcu_read_lock(); 87 opt = flowlabel ? flowlabel->opt : rcu_dereference(np->opt); 88 final_p = fl6_update_dst(&fl6, opt, &final); 89 rcu_read_unlock(); 90 91 dst = ip6_dst_lookup_flow(sk, &fl6, final_p); 92 if (IS_ERR(dst)) { 93 err = PTR_ERR(dst); 94 goto out; 95 } 96 97 if (fix_sk_saddr) { 98 if (ipv6_addr_any(&np->saddr)) 99 np->saddr = fl6.saddr; 100 101 if (ipv6_addr_any(&sk->sk_v6_rcv_saddr)) { 102 sk->sk_v6_rcv_saddr = fl6.saddr; 103 inet->inet_rcv_saddr = LOOPBACK4_IPV6; 104 if (sk->sk_prot->rehash) 105 sk->sk_prot->rehash(sk); 106 } 107 } 108 109 ip6_sk_dst_store_flow(sk, dst, &fl6); 110 111 out: 112 fl6_sock_release(flowlabel); 113 return err; 114 } 115 116 void ip6_datagram_release_cb(struct sock *sk) 117 { 118 struct dst_entry *dst; 119 120 if (ipv6_addr_v4mapped(&sk->sk_v6_daddr)) 121 return; 122 123 rcu_read_lock(); 124 dst = __sk_dst_get(sk); 125 if (!dst || !dst->obsolete || 126 dst->ops->check(dst, inet6_sk(sk)->dst_cookie)) { 127 rcu_read_unlock(); 128 return; 129 } 130 rcu_read_unlock(); 131 132 ip6_datagram_dst_update(sk, false); 133 } 134 EXPORT_SYMBOL_GPL(ip6_datagram_release_cb); 135 136 int __ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, 137 int addr_len) 138 { 139 struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr; 140 struct inet_sock *inet = inet_sk(sk); 141 struct ipv6_pinfo *np = inet6_sk(sk); 142 struct in6_addr *daddr, old_daddr; 143 __be32 fl6_flowlabel = 0; 144 __be32 old_fl6_flowlabel; 145 __be16 old_dport; 146 int addr_type; 147 int err; 148 149 if (usin->sin6_family == AF_INET) { 150 if (__ipv6_only_sock(sk)) 151 return -EAFNOSUPPORT; 152 err = __ip4_datagram_connect(sk, uaddr, addr_len); 153 goto ipv4_connected; 154 } 155 156 if (addr_len < SIN6_LEN_RFC2133) 157 return -EINVAL; 158 159 if (usin->sin6_family != AF_INET6) 160 return -EAFNOSUPPORT; 161 162 if (np->sndflow) 163 fl6_flowlabel = usin->sin6_flowinfo & IPV6_FLOWINFO_MASK; 164 165 if (ipv6_addr_any(&usin->sin6_addr)) { 166 /* 167 * connect to self 168 */ 169 if (ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr)) 170 ipv6_addr_set_v4mapped(htonl(INADDR_LOOPBACK), 171 &usin->sin6_addr); 172 else 173 usin->sin6_addr = in6addr_loopback; 174 } 175 176 addr_type = ipv6_addr_type(&usin->sin6_addr); 177 178 daddr = &usin->sin6_addr; 179 180 if (addr_type & IPV6_ADDR_MAPPED) { 181 struct sockaddr_in sin; 182 183 if (__ipv6_only_sock(sk)) { 184 err = -ENETUNREACH; 185 goto out; 186 } 187 sin.sin_family = AF_INET; 188 sin.sin_addr.s_addr = daddr->s6_addr32[3]; 189 sin.sin_port = usin->sin6_port; 190 191 err = __ip4_datagram_connect(sk, 192 (struct sockaddr *) &sin, 193 sizeof(sin)); 194 195 ipv4_connected: 196 if (err) 197 goto out; 198 199 ipv6_addr_set_v4mapped(inet->inet_daddr, &sk->sk_v6_daddr); 200 201 if (ipv6_addr_any(&np->saddr) || 202 ipv6_mapped_addr_any(&np->saddr)) 203 ipv6_addr_set_v4mapped(inet->inet_saddr, &np->saddr); 204 205 if (ipv6_addr_any(&sk->sk_v6_rcv_saddr) || 206 ipv6_mapped_addr_any(&sk->sk_v6_rcv_saddr)) { 207 ipv6_addr_set_v4mapped(inet->inet_rcv_saddr, 208 &sk->sk_v6_rcv_saddr); 209 if (sk->sk_prot->rehash) 210 sk->sk_prot->rehash(sk); 211 } 212 213 goto out; 214 } 215 216 if (__ipv6_addr_needs_scope_id(addr_type)) { 217 if (addr_len >= sizeof(struct sockaddr_in6) && 218 usin->sin6_scope_id) { 219 if (!sk_dev_equal_l3scope(sk, usin->sin6_scope_id)) { 220 err = -EINVAL; 221 goto out; 222 } 223 sk->sk_bound_dev_if = usin->sin6_scope_id; 224 } 225 226 if (!sk->sk_bound_dev_if && (addr_type & IPV6_ADDR_MULTICAST)) 227 sk->sk_bound_dev_if = np->mcast_oif; 228 229 /* Connect to link-local address requires an interface */ 230 if (!sk->sk_bound_dev_if) { 231 err = -EINVAL; 232 goto out; 233 } 234 } 235 236 /* save the current peer information before updating it */ 237 old_daddr = sk->sk_v6_daddr; 238 old_fl6_flowlabel = np->flow_label; 239 old_dport = inet->inet_dport; 240 241 sk->sk_v6_daddr = *daddr; 242 np->flow_label = fl6_flowlabel; 243 inet->inet_dport = usin->sin6_port; 244 245 /* 246 * Check for a route to destination an obtain the 247 * destination cache for it. 248 */ 249 250 err = ip6_datagram_dst_update(sk, true); 251 if (err) { 252 /* Restore the socket peer info, to keep it consistent with 253 * the old socket state 254 */ 255 sk->sk_v6_daddr = old_daddr; 256 np->flow_label = old_fl6_flowlabel; 257 inet->inet_dport = old_dport; 258 goto out; 259 } 260 261 sk->sk_state = TCP_ESTABLISHED; 262 sk_set_txhash(sk); 263 out: 264 return err; 265 } 266 EXPORT_SYMBOL_GPL(__ip6_datagram_connect); 267 268 int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) 269 { 270 int res; 271 272 lock_sock(sk); 273 res = __ip6_datagram_connect(sk, uaddr, addr_len); 274 release_sock(sk); 275 return res; 276 } 277 EXPORT_SYMBOL_GPL(ip6_datagram_connect); 278 279 int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *uaddr, 280 int addr_len) 281 { 282 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, uaddr); 283 if (sin6->sin6_family != AF_INET6) 284 return -EAFNOSUPPORT; 285 return ip6_datagram_connect(sk, uaddr, addr_len); 286 } 287 EXPORT_SYMBOL_GPL(ip6_datagram_connect_v6_only); 288 289 void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err, 290 __be16 port, u32 info, u8 *payload) 291 { 292 struct ipv6_pinfo *np = inet6_sk(sk); 293 struct icmp6hdr *icmph = icmp6_hdr(skb); 294 struct sock_exterr_skb *serr; 295 296 if (!np->recverr) 297 return; 298 299 skb = skb_clone(skb, GFP_ATOMIC); 300 if (!skb) 301 return; 302 303 skb->protocol = htons(ETH_P_IPV6); 304 305 serr = SKB_EXT_ERR(skb); 306 serr->ee.ee_errno = err; 307 serr->ee.ee_origin = SO_EE_ORIGIN_ICMP6; 308 serr->ee.ee_type = icmph->icmp6_type; 309 serr->ee.ee_code = icmph->icmp6_code; 310 serr->ee.ee_pad = 0; 311 serr->ee.ee_info = info; 312 serr->ee.ee_data = 0; 313 serr->addr_offset = (u8 *)&(((struct ipv6hdr *)(icmph + 1))->daddr) - 314 skb_network_header(skb); 315 serr->port = port; 316 317 __skb_pull(skb, payload - skb->data); 318 skb_reset_transport_header(skb); 319 320 if (sock_queue_err_skb(sk, skb)) 321 kfree_skb(skb); 322 } 323 324 void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info) 325 { 326 const struct ipv6_pinfo *np = inet6_sk(sk); 327 struct sock_exterr_skb *serr; 328 struct ipv6hdr *iph; 329 struct sk_buff *skb; 330 331 if (!np->recverr) 332 return; 333 334 skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC); 335 if (!skb) 336 return; 337 338 skb->protocol = htons(ETH_P_IPV6); 339 340 skb_put(skb, sizeof(struct ipv6hdr)); 341 skb_reset_network_header(skb); 342 iph = ipv6_hdr(skb); 343 iph->daddr = fl6->daddr; 344 345 serr = SKB_EXT_ERR(skb); 346 serr->ee.ee_errno = err; 347 serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL; 348 serr->ee.ee_type = 0; 349 serr->ee.ee_code = 0; 350 serr->ee.ee_pad = 0; 351 serr->ee.ee_info = info; 352 serr->ee.ee_data = 0; 353 serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb); 354 serr->port = fl6->fl6_dport; 355 356 __skb_pull(skb, skb_tail_pointer(skb) - skb->data); 357 skb_reset_transport_header(skb); 358 359 if (sock_queue_err_skb(sk, skb)) 360 kfree_skb(skb); 361 } 362 363 void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu) 364 { 365 struct ipv6_pinfo *np = inet6_sk(sk); 366 struct ipv6hdr *iph; 367 struct sk_buff *skb; 368 struct ip6_mtuinfo *mtu_info; 369 370 if (!np->rxopt.bits.rxpmtu) 371 return; 372 373 skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC); 374 if (!skb) 375 return; 376 377 skb_put(skb, sizeof(struct ipv6hdr)); 378 skb_reset_network_header(skb); 379 iph = ipv6_hdr(skb); 380 iph->daddr = fl6->daddr; 381 382 mtu_info = IP6CBMTU(skb); 383 384 mtu_info->ip6m_mtu = mtu; 385 mtu_info->ip6m_addr.sin6_family = AF_INET6; 386 mtu_info->ip6m_addr.sin6_port = 0; 387 mtu_info->ip6m_addr.sin6_flowinfo = 0; 388 mtu_info->ip6m_addr.sin6_scope_id = fl6->flowi6_oif; 389 mtu_info->ip6m_addr.sin6_addr = ipv6_hdr(skb)->daddr; 390 391 __skb_pull(skb, skb_tail_pointer(skb) - skb->data); 392 skb_reset_transport_header(skb); 393 394 skb = xchg(&np->rxpmtu, skb); 395 kfree_skb(skb); 396 } 397 398 /* For some errors we have valid addr_offset even with zero payload and 399 * zero port. Also, addr_offset should be supported if port is set. 400 */ 401 static inline bool ipv6_datagram_support_addr(struct sock_exterr_skb *serr) 402 { 403 return serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6 || 404 serr->ee.ee_origin == SO_EE_ORIGIN_ICMP || 405 serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL || serr->port; 406 } 407 408 /* IPv6 supports cmsg on all origins aside from SO_EE_ORIGIN_LOCAL. 409 * 410 * At one point, excluding local errors was a quick test to identify icmp/icmp6 411 * errors. This is no longer true, but the test remained, so the v6 stack, 412 * unlike v4, also honors cmsg requests on all wifi and timestamp errors. 413 */ 414 static bool ip6_datagram_support_cmsg(struct sk_buff *skb, 415 struct sock_exterr_skb *serr) 416 { 417 if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP || 418 serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6) 419 return true; 420 421 if (serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL) 422 return false; 423 424 if (!IP6CB(skb)->iif) 425 return false; 426 427 return true; 428 } 429 430 /* 431 * Handle MSG_ERRQUEUE 432 */ 433 int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len) 434 { 435 struct ipv6_pinfo *np = inet6_sk(sk); 436 struct sock_exterr_skb *serr; 437 struct sk_buff *skb; 438 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name); 439 struct { 440 struct sock_extended_err ee; 441 struct sockaddr_in6 offender; 442 } errhdr; 443 int err; 444 int copied; 445 446 err = -EAGAIN; 447 skb = sock_dequeue_err_skb(sk); 448 if (!skb) 449 goto out; 450 451 copied = skb->len; 452 if (copied > len) { 453 msg->msg_flags |= MSG_TRUNC; 454 copied = len; 455 } 456 err = skb_copy_datagram_msg(skb, 0, msg, copied); 457 if (unlikely(err)) { 458 kfree_skb(skb); 459 return err; 460 } 461 sock_recv_timestamp(msg, sk, skb); 462 463 serr = SKB_EXT_ERR(skb); 464 465 if (sin && ipv6_datagram_support_addr(serr)) { 466 const unsigned char *nh = skb_network_header(skb); 467 sin->sin6_family = AF_INET6; 468 sin->sin6_flowinfo = 0; 469 sin->sin6_port = serr->port; 470 if (skb->protocol == htons(ETH_P_IPV6)) { 471 const struct ipv6hdr *ip6h = container_of((struct in6_addr *)(nh + serr->addr_offset), 472 struct ipv6hdr, daddr); 473 sin->sin6_addr = ip6h->daddr; 474 if (np->sndflow) 475 sin->sin6_flowinfo = ip6_flowinfo(ip6h); 476 sin->sin6_scope_id = 477 ipv6_iface_scope_id(&sin->sin6_addr, 478 IP6CB(skb)->iif); 479 } else { 480 ipv6_addr_set_v4mapped(*(__be32 *)(nh + serr->addr_offset), 481 &sin->sin6_addr); 482 sin->sin6_scope_id = 0; 483 } 484 *addr_len = sizeof(*sin); 485 } 486 487 memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err)); 488 sin = &errhdr.offender; 489 memset(sin, 0, sizeof(*sin)); 490 491 if (ip6_datagram_support_cmsg(skb, serr)) { 492 sin->sin6_family = AF_INET6; 493 if (np->rxopt.all) 494 ip6_datagram_recv_common_ctl(sk, msg, skb); 495 if (skb->protocol == htons(ETH_P_IPV6)) { 496 sin->sin6_addr = ipv6_hdr(skb)->saddr; 497 if (np->rxopt.all) 498 ip6_datagram_recv_specific_ctl(sk, msg, skb); 499 sin->sin6_scope_id = 500 ipv6_iface_scope_id(&sin->sin6_addr, 501 IP6CB(skb)->iif); 502 } else { 503 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr, 504 &sin->sin6_addr); 505 if (inet_sk(sk)->cmsg_flags) 506 ip_cmsg_recv(msg, skb); 507 } 508 } 509 510 put_cmsg(msg, SOL_IPV6, IPV6_RECVERR, sizeof(errhdr), &errhdr); 511 512 /* Now we could try to dump offended packet options */ 513 514 msg->msg_flags |= MSG_ERRQUEUE; 515 err = copied; 516 517 consume_skb(skb); 518 out: 519 return err; 520 } 521 EXPORT_SYMBOL_GPL(ipv6_recv_error); 522 523 /* 524 * Handle IPV6_RECVPATHMTU 525 */ 526 int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len, 527 int *addr_len) 528 { 529 struct ipv6_pinfo *np = inet6_sk(sk); 530 struct sk_buff *skb; 531 struct ip6_mtuinfo mtu_info; 532 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name); 533 int err; 534 int copied; 535 536 err = -EAGAIN; 537 skb = xchg(&np->rxpmtu, NULL); 538 if (!skb) 539 goto out; 540 541 copied = skb->len; 542 if (copied > len) { 543 msg->msg_flags |= MSG_TRUNC; 544 copied = len; 545 } 546 err = skb_copy_datagram_msg(skb, 0, msg, copied); 547 if (err) 548 goto out_free_skb; 549 550 sock_recv_timestamp(msg, sk, skb); 551 552 memcpy(&mtu_info, IP6CBMTU(skb), sizeof(mtu_info)); 553 554 if (sin) { 555 sin->sin6_family = AF_INET6; 556 sin->sin6_flowinfo = 0; 557 sin->sin6_port = 0; 558 sin->sin6_scope_id = mtu_info.ip6m_addr.sin6_scope_id; 559 sin->sin6_addr = mtu_info.ip6m_addr.sin6_addr; 560 *addr_len = sizeof(*sin); 561 } 562 563 put_cmsg(msg, SOL_IPV6, IPV6_PATHMTU, sizeof(mtu_info), &mtu_info); 564 565 err = copied; 566 567 out_free_skb: 568 kfree_skb(skb); 569 out: 570 return err; 571 } 572 573 574 void ip6_datagram_recv_common_ctl(struct sock *sk, struct msghdr *msg, 575 struct sk_buff *skb) 576 { 577 struct ipv6_pinfo *np = inet6_sk(sk); 578 bool is_ipv6 = skb->protocol == htons(ETH_P_IPV6); 579 580 if (np->rxopt.bits.rxinfo) { 581 struct in6_pktinfo src_info; 582 583 if (is_ipv6) { 584 src_info.ipi6_ifindex = IP6CB(skb)->iif; 585 src_info.ipi6_addr = ipv6_hdr(skb)->daddr; 586 } else { 587 src_info.ipi6_ifindex = 588 PKTINFO_SKB_CB(skb)->ipi_ifindex; 589 ipv6_addr_set_v4mapped(ip_hdr(skb)->daddr, 590 &src_info.ipi6_addr); 591 } 592 593 if (src_info.ipi6_ifindex >= 0) 594 put_cmsg(msg, SOL_IPV6, IPV6_PKTINFO, 595 sizeof(src_info), &src_info); 596 } 597 } 598 599 void ip6_datagram_recv_specific_ctl(struct sock *sk, struct msghdr *msg, 600 struct sk_buff *skb) 601 { 602 struct ipv6_pinfo *np = inet6_sk(sk); 603 struct inet6_skb_parm *opt = IP6CB(skb); 604 unsigned char *nh = skb_network_header(skb); 605 606 if (np->rxopt.bits.rxhlim) { 607 int hlim = ipv6_hdr(skb)->hop_limit; 608 put_cmsg(msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim); 609 } 610 611 if (np->rxopt.bits.rxtclass) { 612 int tclass = ipv6_get_dsfield(ipv6_hdr(skb)); 613 put_cmsg(msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass); 614 } 615 616 if (np->rxopt.bits.rxflow) { 617 __be32 flowinfo = ip6_flowinfo((struct ipv6hdr *)nh); 618 if (flowinfo) 619 put_cmsg(msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo); 620 } 621 622 /* HbH is allowed only once */ 623 if (np->rxopt.bits.hopopts && (opt->flags & IP6SKB_HOPBYHOP)) { 624 u8 *ptr = nh + sizeof(struct ipv6hdr); 625 put_cmsg(msg, SOL_IPV6, IPV6_HOPOPTS, (ptr[1]+1)<<3, ptr); 626 } 627 628 if (opt->lastopt && 629 (np->rxopt.bits.dstopts || np->rxopt.bits.srcrt)) { 630 /* 631 * Silly enough, but we need to reparse in order to 632 * report extension headers (except for HbH) 633 * in order. 634 * 635 * Also note that IPV6_RECVRTHDRDSTOPTS is NOT 636 * (and WILL NOT be) defined because 637 * IPV6_RECVDSTOPTS is more generic. --yoshfuji 638 */ 639 unsigned int off = sizeof(struct ipv6hdr); 640 u8 nexthdr = ipv6_hdr(skb)->nexthdr; 641 642 while (off <= opt->lastopt) { 643 unsigned int len; 644 u8 *ptr = nh + off; 645 646 switch (nexthdr) { 647 case IPPROTO_DSTOPTS: 648 nexthdr = ptr[0]; 649 len = (ptr[1] + 1) << 3; 650 if (np->rxopt.bits.dstopts) 651 put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, len, ptr); 652 break; 653 case IPPROTO_ROUTING: 654 nexthdr = ptr[0]; 655 len = (ptr[1] + 1) << 3; 656 if (np->rxopt.bits.srcrt) 657 put_cmsg(msg, SOL_IPV6, IPV6_RTHDR, len, ptr); 658 break; 659 case IPPROTO_AH: 660 nexthdr = ptr[0]; 661 len = (ptr[1] + 2) << 2; 662 break; 663 default: 664 nexthdr = ptr[0]; 665 len = (ptr[1] + 1) << 3; 666 break; 667 } 668 669 off += len; 670 } 671 } 672 673 /* socket options in old style */ 674 if (np->rxopt.bits.rxoinfo) { 675 struct in6_pktinfo src_info; 676 677 src_info.ipi6_ifindex = opt->iif; 678 src_info.ipi6_addr = ipv6_hdr(skb)->daddr; 679 put_cmsg(msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info); 680 } 681 if (np->rxopt.bits.rxohlim) { 682 int hlim = ipv6_hdr(skb)->hop_limit; 683 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim); 684 } 685 if (np->rxopt.bits.ohopopts && (opt->flags & IP6SKB_HOPBYHOP)) { 686 u8 *ptr = nh + sizeof(struct ipv6hdr); 687 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPOPTS, (ptr[1]+1)<<3, ptr); 688 } 689 if (np->rxopt.bits.odstopts && opt->dst0) { 690 u8 *ptr = nh + opt->dst0; 691 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr); 692 } 693 if (np->rxopt.bits.osrcrt && opt->srcrt) { 694 struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(nh + opt->srcrt); 695 put_cmsg(msg, SOL_IPV6, IPV6_2292RTHDR, (rthdr->hdrlen+1) << 3, rthdr); 696 } 697 if (np->rxopt.bits.odstopts && opt->dst1) { 698 u8 *ptr = nh + opt->dst1; 699 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr); 700 } 701 if (np->rxopt.bits.rxorigdstaddr) { 702 struct sockaddr_in6 sin6; 703 __be16 *ports; 704 int end; 705 706 end = skb_transport_offset(skb) + 4; 707 if (end <= 0 || pskb_may_pull(skb, end)) { 708 /* All current transport protocols have the port numbers in the 709 * first four bytes of the transport header and this function is 710 * written with this assumption in mind. 711 */ 712 ports = (__be16 *)skb_transport_header(skb); 713 714 sin6.sin6_family = AF_INET6; 715 sin6.sin6_addr = ipv6_hdr(skb)->daddr; 716 sin6.sin6_port = ports[1]; 717 sin6.sin6_flowinfo = 0; 718 sin6.sin6_scope_id = 719 ipv6_iface_scope_id(&ipv6_hdr(skb)->daddr, 720 opt->iif); 721 722 put_cmsg(msg, SOL_IPV6, IPV6_ORIGDSTADDR, sizeof(sin6), &sin6); 723 } 724 } 725 if (np->rxopt.bits.recvfragsize && opt->frag_max_size) { 726 int val = opt->frag_max_size; 727 728 put_cmsg(msg, SOL_IPV6, IPV6_RECVFRAGSIZE, sizeof(val), &val); 729 } 730 } 731 732 void ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg, 733 struct sk_buff *skb) 734 { 735 ip6_datagram_recv_common_ctl(sk, msg, skb); 736 ip6_datagram_recv_specific_ctl(sk, msg, skb); 737 } 738 EXPORT_SYMBOL_GPL(ip6_datagram_recv_ctl); 739 740 int ip6_datagram_send_ctl(struct net *net, struct sock *sk, 741 struct msghdr *msg, struct flowi6 *fl6, 742 struct ipcm6_cookie *ipc6) 743 { 744 struct in6_pktinfo *src_info; 745 struct cmsghdr *cmsg; 746 struct ipv6_rt_hdr *rthdr; 747 struct ipv6_opt_hdr *hdr; 748 struct ipv6_txoptions *opt = ipc6->opt; 749 int len; 750 int err = 0; 751 752 for_each_cmsghdr(cmsg, msg) { 753 int addr_type; 754 755 if (!CMSG_OK(msg, cmsg)) { 756 err = -EINVAL; 757 goto exit_f; 758 } 759 760 if (cmsg->cmsg_level == SOL_SOCKET) { 761 err = __sock_cmsg_send(sk, msg, cmsg, &ipc6->sockc); 762 if (err) 763 return err; 764 continue; 765 } 766 767 if (cmsg->cmsg_level != SOL_IPV6) 768 continue; 769 770 switch (cmsg->cmsg_type) { 771 case IPV6_PKTINFO: 772 case IPV6_2292PKTINFO: 773 { 774 struct net_device *dev = NULL; 775 776 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct in6_pktinfo))) { 777 err = -EINVAL; 778 goto exit_f; 779 } 780 781 src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg); 782 783 if (src_info->ipi6_ifindex) { 784 if (fl6->flowi6_oif && 785 src_info->ipi6_ifindex != fl6->flowi6_oif) 786 return -EINVAL; 787 fl6->flowi6_oif = src_info->ipi6_ifindex; 788 } 789 790 addr_type = __ipv6_addr_type(&src_info->ipi6_addr); 791 792 rcu_read_lock(); 793 if (fl6->flowi6_oif) { 794 dev = dev_get_by_index_rcu(net, fl6->flowi6_oif); 795 if (!dev) { 796 rcu_read_unlock(); 797 return -ENODEV; 798 } 799 } else if (addr_type & IPV6_ADDR_LINKLOCAL) { 800 rcu_read_unlock(); 801 return -EINVAL; 802 } 803 804 if (addr_type != IPV6_ADDR_ANY) { 805 int strict = __ipv6_addr_src_scope(addr_type) <= IPV6_ADDR_SCOPE_LINKLOCAL; 806 if (!(net->ipv6.sysctl.ip_nonlocal_bind || 807 inet_sk(sk)->freebind || inet_sk(sk)->transparent) && 808 !ipv6_chk_addr_and_flags(net, &src_info->ipi6_addr, 809 dev, !strict, 0, 810 IFA_F_TENTATIVE) && 811 !ipv6_chk_acast_addr_src(net, dev, 812 &src_info->ipi6_addr)) 813 err = -EINVAL; 814 else 815 fl6->saddr = src_info->ipi6_addr; 816 } 817 818 rcu_read_unlock(); 819 820 if (err) 821 goto exit_f; 822 823 break; 824 } 825 826 case IPV6_FLOWINFO: 827 if (cmsg->cmsg_len < CMSG_LEN(4)) { 828 err = -EINVAL; 829 goto exit_f; 830 } 831 832 if (fl6->flowlabel&IPV6_FLOWINFO_MASK) { 833 if ((fl6->flowlabel^*(__be32 *)CMSG_DATA(cmsg))&~IPV6_FLOWINFO_MASK) { 834 err = -EINVAL; 835 goto exit_f; 836 } 837 } 838 fl6->flowlabel = IPV6_FLOWINFO_MASK & *(__be32 *)CMSG_DATA(cmsg); 839 break; 840 841 case IPV6_2292HOPOPTS: 842 case IPV6_HOPOPTS: 843 if (opt->hopopt || cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) { 844 err = -EINVAL; 845 goto exit_f; 846 } 847 848 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg); 849 len = ((hdr->hdrlen + 1) << 3); 850 if (cmsg->cmsg_len < CMSG_LEN(len)) { 851 err = -EINVAL; 852 goto exit_f; 853 } 854 if (!ns_capable(net->user_ns, CAP_NET_RAW)) { 855 err = -EPERM; 856 goto exit_f; 857 } 858 opt->opt_nflen += len; 859 opt->hopopt = hdr; 860 break; 861 862 case IPV6_2292DSTOPTS: 863 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) { 864 err = -EINVAL; 865 goto exit_f; 866 } 867 868 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg); 869 len = ((hdr->hdrlen + 1) << 3); 870 if (cmsg->cmsg_len < CMSG_LEN(len)) { 871 err = -EINVAL; 872 goto exit_f; 873 } 874 if (!ns_capable(net->user_ns, CAP_NET_RAW)) { 875 err = -EPERM; 876 goto exit_f; 877 } 878 if (opt->dst1opt) { 879 err = -EINVAL; 880 goto exit_f; 881 } 882 opt->opt_flen += len; 883 opt->dst1opt = hdr; 884 break; 885 886 case IPV6_DSTOPTS: 887 case IPV6_RTHDRDSTOPTS: 888 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) { 889 err = -EINVAL; 890 goto exit_f; 891 } 892 893 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg); 894 len = ((hdr->hdrlen + 1) << 3); 895 if (cmsg->cmsg_len < CMSG_LEN(len)) { 896 err = -EINVAL; 897 goto exit_f; 898 } 899 if (!ns_capable(net->user_ns, CAP_NET_RAW)) { 900 err = -EPERM; 901 goto exit_f; 902 } 903 if (cmsg->cmsg_type == IPV6_DSTOPTS) { 904 opt->opt_flen += len; 905 opt->dst1opt = hdr; 906 } else { 907 opt->opt_nflen += len; 908 opt->dst0opt = hdr; 909 } 910 break; 911 912 case IPV6_2292RTHDR: 913 case IPV6_RTHDR: 914 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_rt_hdr))) { 915 err = -EINVAL; 916 goto exit_f; 917 } 918 919 rthdr = (struct ipv6_rt_hdr *)CMSG_DATA(cmsg); 920 921 switch (rthdr->type) { 922 #if IS_ENABLED(CONFIG_IPV6_MIP6) 923 case IPV6_SRCRT_TYPE_2: 924 if (rthdr->hdrlen != 2 || 925 rthdr->segments_left != 1) { 926 err = -EINVAL; 927 goto exit_f; 928 } 929 break; 930 #endif 931 default: 932 err = -EINVAL; 933 goto exit_f; 934 } 935 936 len = ((rthdr->hdrlen + 1) << 3); 937 938 if (cmsg->cmsg_len < CMSG_LEN(len)) { 939 err = -EINVAL; 940 goto exit_f; 941 } 942 943 /* segments left must also match */ 944 if ((rthdr->hdrlen >> 1) != rthdr->segments_left) { 945 err = -EINVAL; 946 goto exit_f; 947 } 948 949 opt->opt_nflen += len; 950 opt->srcrt = rthdr; 951 952 if (cmsg->cmsg_type == IPV6_2292RTHDR && opt->dst1opt) { 953 int dsthdrlen = ((opt->dst1opt->hdrlen+1)<<3); 954 955 opt->opt_nflen += dsthdrlen; 956 opt->dst0opt = opt->dst1opt; 957 opt->dst1opt = NULL; 958 opt->opt_flen -= dsthdrlen; 959 } 960 961 break; 962 963 case IPV6_2292HOPLIMIT: 964 case IPV6_HOPLIMIT: 965 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) { 966 err = -EINVAL; 967 goto exit_f; 968 } 969 970 ipc6->hlimit = *(int *)CMSG_DATA(cmsg); 971 if (ipc6->hlimit < -1 || ipc6->hlimit > 0xff) { 972 err = -EINVAL; 973 goto exit_f; 974 } 975 976 break; 977 978 case IPV6_TCLASS: 979 { 980 int tc; 981 982 err = -EINVAL; 983 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) 984 goto exit_f; 985 986 tc = *(int *)CMSG_DATA(cmsg); 987 if (tc < -1 || tc > 0xff) 988 goto exit_f; 989 990 err = 0; 991 ipc6->tclass = tc; 992 993 break; 994 } 995 996 case IPV6_DONTFRAG: 997 { 998 int df; 999 1000 err = -EINVAL; 1001 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) 1002 goto exit_f; 1003 1004 df = *(int *)CMSG_DATA(cmsg); 1005 if (df < 0 || df > 1) 1006 goto exit_f; 1007 1008 err = 0; 1009 ipc6->dontfrag = df; 1010 1011 break; 1012 } 1013 default: 1014 net_dbg_ratelimited("invalid cmsg type: %d\n", 1015 cmsg->cmsg_type); 1016 err = -EINVAL; 1017 goto exit_f; 1018 } 1019 } 1020 1021 exit_f: 1022 return err; 1023 } 1024 EXPORT_SYMBOL_GPL(ip6_datagram_send_ctl); 1025 1026 void __ip6_dgram_sock_seq_show(struct seq_file *seq, struct sock *sp, 1027 __u16 srcp, __u16 destp, int rqueue, int bucket) 1028 { 1029 const struct in6_addr *dest, *src; 1030 1031 dest = &sp->sk_v6_daddr; 1032 src = &sp->sk_v6_rcv_saddr; 1033 seq_printf(seq, 1034 "%5d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " 1035 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %d\n", 1036 bucket, 1037 src->s6_addr32[0], src->s6_addr32[1], 1038 src->s6_addr32[2], src->s6_addr32[3], srcp, 1039 dest->s6_addr32[0], dest->s6_addr32[1], 1040 dest->s6_addr32[2], dest->s6_addr32[3], destp, 1041 sp->sk_state, 1042 sk_wmem_alloc_get(sp), 1043 rqueue, 1044 0, 0L, 0, 1045 from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)), 1046 0, 1047 sock_i_ino(sp), 1048 refcount_read(&sp->sk_refcnt), sp, 1049 atomic_read(&sp->sk_drops)); 1050 } 1051