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_dst_store(sk, dst, 110 ipv6_addr_equal(&fl6.daddr, &sk->sk_v6_daddr) ? 111 &sk->sk_v6_daddr : NULL, 112 #ifdef CONFIG_IPV6_SUBTREES 113 ipv6_addr_equal(&fl6.saddr, &np->saddr) ? 114 &np->saddr : 115 #endif 116 NULL); 117 118 out: 119 fl6_sock_release(flowlabel); 120 return err; 121 } 122 123 void ip6_datagram_release_cb(struct sock *sk) 124 { 125 struct dst_entry *dst; 126 127 if (ipv6_addr_v4mapped(&sk->sk_v6_daddr)) 128 return; 129 130 rcu_read_lock(); 131 dst = __sk_dst_get(sk); 132 if (!dst || !dst->obsolete || 133 dst->ops->check(dst, inet6_sk(sk)->dst_cookie)) { 134 rcu_read_unlock(); 135 return; 136 } 137 rcu_read_unlock(); 138 139 ip6_datagram_dst_update(sk, false); 140 } 141 EXPORT_SYMBOL_GPL(ip6_datagram_release_cb); 142 143 int __ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, 144 int addr_len) 145 { 146 struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr; 147 struct inet_sock *inet = inet_sk(sk); 148 struct ipv6_pinfo *np = inet6_sk(sk); 149 struct in6_addr *daddr; 150 int addr_type; 151 int err; 152 __be32 fl6_flowlabel = 0; 153 154 if (usin->sin6_family == AF_INET) { 155 if (__ipv6_only_sock(sk)) 156 return -EAFNOSUPPORT; 157 err = __ip4_datagram_connect(sk, uaddr, addr_len); 158 goto ipv4_connected; 159 } 160 161 if (addr_len < SIN6_LEN_RFC2133) 162 return -EINVAL; 163 164 if (usin->sin6_family != AF_INET6) 165 return -EAFNOSUPPORT; 166 167 if (np->sndflow) 168 fl6_flowlabel = usin->sin6_flowinfo & IPV6_FLOWINFO_MASK; 169 170 if (ipv6_addr_any(&usin->sin6_addr)) { 171 /* 172 * connect to self 173 */ 174 if (ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr)) 175 ipv6_addr_set_v4mapped(htonl(INADDR_LOOPBACK), 176 &usin->sin6_addr); 177 else 178 usin->sin6_addr = in6addr_loopback; 179 } 180 181 addr_type = ipv6_addr_type(&usin->sin6_addr); 182 183 daddr = &usin->sin6_addr; 184 185 if (addr_type & IPV6_ADDR_MAPPED) { 186 struct sockaddr_in sin; 187 188 if (__ipv6_only_sock(sk)) { 189 err = -ENETUNREACH; 190 goto out; 191 } 192 sin.sin_family = AF_INET; 193 sin.sin_addr.s_addr = daddr->s6_addr32[3]; 194 sin.sin_port = usin->sin6_port; 195 196 err = __ip4_datagram_connect(sk, 197 (struct sockaddr *) &sin, 198 sizeof(sin)); 199 200 ipv4_connected: 201 if (err) 202 goto out; 203 204 ipv6_addr_set_v4mapped(inet->inet_daddr, &sk->sk_v6_daddr); 205 206 if (ipv6_addr_any(&np->saddr) || 207 ipv6_mapped_addr_any(&np->saddr)) 208 ipv6_addr_set_v4mapped(inet->inet_saddr, &np->saddr); 209 210 if (ipv6_addr_any(&sk->sk_v6_rcv_saddr) || 211 ipv6_mapped_addr_any(&sk->sk_v6_rcv_saddr)) { 212 ipv6_addr_set_v4mapped(inet->inet_rcv_saddr, 213 &sk->sk_v6_rcv_saddr); 214 if (sk->sk_prot->rehash) 215 sk->sk_prot->rehash(sk); 216 } 217 218 goto out; 219 } 220 221 if (__ipv6_addr_needs_scope_id(addr_type)) { 222 if (addr_len >= sizeof(struct sockaddr_in6) && 223 usin->sin6_scope_id) { 224 if (sk->sk_bound_dev_if && 225 sk->sk_bound_dev_if != usin->sin6_scope_id) { 226 err = -EINVAL; 227 goto out; 228 } 229 sk->sk_bound_dev_if = usin->sin6_scope_id; 230 } 231 232 if (!sk->sk_bound_dev_if && (addr_type & IPV6_ADDR_MULTICAST)) 233 sk->sk_bound_dev_if = np->mcast_oif; 234 235 /* Connect to link-local address requires an interface */ 236 if (!sk->sk_bound_dev_if) { 237 err = -EINVAL; 238 goto out; 239 } 240 } 241 242 sk->sk_v6_daddr = *daddr; 243 np->flow_label = fl6_flowlabel; 244 245 inet->inet_dport = usin->sin6_port; 246 247 /* 248 * Check for a route to destination an obtain the 249 * destination cache for it. 250 */ 251 252 err = ip6_datagram_dst_update(sk, true); 253 if (err) { 254 /* Reset daddr and dport so that udp_v6_early_demux() 255 * fails to find this socket 256 */ 257 memset(&sk->sk_v6_daddr, 0, sizeof(sk->sk_v6_daddr)); 258 inet->inet_dport = 0; 259 goto out; 260 } 261 262 sk->sk_state = TCP_ESTABLISHED; 263 sk_set_txhash(sk); 264 out: 265 return err; 266 } 267 EXPORT_SYMBOL_GPL(__ip6_datagram_connect); 268 269 int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) 270 { 271 int res; 272 273 lock_sock(sk); 274 res = __ip6_datagram_connect(sk, uaddr, addr_len); 275 release_sock(sk); 276 return res; 277 } 278 EXPORT_SYMBOL_GPL(ip6_datagram_connect); 279 280 int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *uaddr, 281 int addr_len) 282 { 283 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, uaddr); 284 if (sin6->sin6_family != AF_INET6) 285 return -EAFNOSUPPORT; 286 return ip6_datagram_connect(sk, uaddr, addr_len); 287 } 288 EXPORT_SYMBOL_GPL(ip6_datagram_connect_v6_only); 289 290 void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err, 291 __be16 port, u32 info, u8 *payload) 292 { 293 struct ipv6_pinfo *np = inet6_sk(sk); 294 struct icmp6hdr *icmph = icmp6_hdr(skb); 295 struct sock_exterr_skb *serr; 296 297 if (!np->recverr) 298 return; 299 300 skb = skb_clone(skb, GFP_ATOMIC); 301 if (!skb) 302 return; 303 304 skb->protocol = htons(ETH_P_IPV6); 305 306 serr = SKB_EXT_ERR(skb); 307 serr->ee.ee_errno = err; 308 serr->ee.ee_origin = SO_EE_ORIGIN_ICMP6; 309 serr->ee.ee_type = icmph->icmp6_type; 310 serr->ee.ee_code = icmph->icmp6_code; 311 serr->ee.ee_pad = 0; 312 serr->ee.ee_info = info; 313 serr->ee.ee_data = 0; 314 serr->addr_offset = (u8 *)&(((struct ipv6hdr *)(icmph + 1))->daddr) - 315 skb_network_header(skb); 316 serr->port = port; 317 318 __skb_pull(skb, payload - skb->data); 319 skb_reset_transport_header(skb); 320 321 if (sock_queue_err_skb(sk, skb)) 322 kfree_skb(skb); 323 } 324 325 void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info) 326 { 327 const struct ipv6_pinfo *np = inet6_sk(sk); 328 struct sock_exterr_skb *serr; 329 struct ipv6hdr *iph; 330 struct sk_buff *skb; 331 332 if (!np->recverr) 333 return; 334 335 skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC); 336 if (!skb) 337 return; 338 339 skb->protocol = htons(ETH_P_IPV6); 340 341 skb_put(skb, sizeof(struct ipv6hdr)); 342 skb_reset_network_header(skb); 343 iph = ipv6_hdr(skb); 344 iph->daddr = fl6->daddr; 345 346 serr = SKB_EXT_ERR(skb); 347 serr->ee.ee_errno = err; 348 serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL; 349 serr->ee.ee_type = 0; 350 serr->ee.ee_code = 0; 351 serr->ee.ee_pad = 0; 352 serr->ee.ee_info = info; 353 serr->ee.ee_data = 0; 354 serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb); 355 serr->port = fl6->fl6_dport; 356 357 __skb_pull(skb, skb_tail_pointer(skb) - skb->data); 358 skb_reset_transport_header(skb); 359 360 if (sock_queue_err_skb(sk, skb)) 361 kfree_skb(skb); 362 } 363 364 void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu) 365 { 366 struct ipv6_pinfo *np = inet6_sk(sk); 367 struct ipv6hdr *iph; 368 struct sk_buff *skb; 369 struct ip6_mtuinfo *mtu_info; 370 371 if (!np->rxopt.bits.rxpmtu) 372 return; 373 374 skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC); 375 if (!skb) 376 return; 377 378 skb_put(skb, sizeof(struct ipv6hdr)); 379 skb_reset_network_header(skb); 380 iph = ipv6_hdr(skb); 381 iph->daddr = fl6->daddr; 382 383 mtu_info = IP6CBMTU(skb); 384 385 mtu_info->ip6m_mtu = mtu; 386 mtu_info->ip6m_addr.sin6_family = AF_INET6; 387 mtu_info->ip6m_addr.sin6_port = 0; 388 mtu_info->ip6m_addr.sin6_flowinfo = 0; 389 mtu_info->ip6m_addr.sin6_scope_id = fl6->flowi6_oif; 390 mtu_info->ip6m_addr.sin6_addr = ipv6_hdr(skb)->daddr; 391 392 __skb_pull(skb, skb_tail_pointer(skb) - skb->data); 393 skb_reset_transport_header(skb); 394 395 skb = xchg(&np->rxpmtu, skb); 396 kfree_skb(skb); 397 } 398 399 /* For some errors we have valid addr_offset even with zero payload and 400 * zero port. Also, addr_offset should be supported if port is set. 401 */ 402 static inline bool ipv6_datagram_support_addr(struct sock_exterr_skb *serr) 403 { 404 return serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6 || 405 serr->ee.ee_origin == SO_EE_ORIGIN_ICMP || 406 serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL || serr->port; 407 } 408 409 /* IPv6 supports cmsg on all origins aside from SO_EE_ORIGIN_LOCAL. 410 * 411 * At one point, excluding local errors was a quick test to identify icmp/icmp6 412 * errors. This is no longer true, but the test remained, so the v6 stack, 413 * unlike v4, also honors cmsg requests on all wifi and timestamp errors. 414 */ 415 static bool ip6_datagram_support_cmsg(struct sk_buff *skb, 416 struct sock_exterr_skb *serr) 417 { 418 if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP || 419 serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6) 420 return true; 421 422 if (serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL) 423 return false; 424 425 if (!IP6CB(skb)->iif) 426 return false; 427 428 return true; 429 } 430 431 /* 432 * Handle MSG_ERRQUEUE 433 */ 434 int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len) 435 { 436 struct ipv6_pinfo *np = inet6_sk(sk); 437 struct sock_exterr_skb *serr; 438 struct sk_buff *skb; 439 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name); 440 struct { 441 struct sock_extended_err ee; 442 struct sockaddr_in6 offender; 443 } errhdr; 444 int err; 445 int copied; 446 447 err = -EAGAIN; 448 skb = sock_dequeue_err_skb(sk); 449 if (!skb) 450 goto out; 451 452 copied = skb->len; 453 if (copied > len) { 454 msg->msg_flags |= MSG_TRUNC; 455 copied = len; 456 } 457 err = skb_copy_datagram_msg(skb, 0, msg, copied); 458 if (unlikely(err)) { 459 kfree_skb(skb); 460 return err; 461 } 462 sock_recv_timestamp(msg, sk, skb); 463 464 serr = SKB_EXT_ERR(skb); 465 466 if (sin && ipv6_datagram_support_addr(serr)) { 467 const unsigned char *nh = skb_network_header(skb); 468 sin->sin6_family = AF_INET6; 469 sin->sin6_flowinfo = 0; 470 sin->sin6_port = serr->port; 471 if (skb->protocol == htons(ETH_P_IPV6)) { 472 const struct ipv6hdr *ip6h = container_of((struct in6_addr *)(nh + serr->addr_offset), 473 struct ipv6hdr, daddr); 474 sin->sin6_addr = ip6h->daddr; 475 if (np->sndflow) 476 sin->sin6_flowinfo = ip6_flowinfo(ip6h); 477 sin->sin6_scope_id = 478 ipv6_iface_scope_id(&sin->sin6_addr, 479 IP6CB(skb)->iif); 480 } else { 481 ipv6_addr_set_v4mapped(*(__be32 *)(nh + serr->addr_offset), 482 &sin->sin6_addr); 483 sin->sin6_scope_id = 0; 484 } 485 *addr_len = sizeof(*sin); 486 } 487 488 memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err)); 489 sin = &errhdr.offender; 490 memset(sin, 0, sizeof(*sin)); 491 492 if (ip6_datagram_support_cmsg(skb, serr)) { 493 sin->sin6_family = AF_INET6; 494 if (np->rxopt.all) 495 ip6_datagram_recv_common_ctl(sk, msg, skb); 496 if (skb->protocol == htons(ETH_P_IPV6)) { 497 sin->sin6_addr = ipv6_hdr(skb)->saddr; 498 if (np->rxopt.all) 499 ip6_datagram_recv_specific_ctl(sk, msg, skb); 500 sin->sin6_scope_id = 501 ipv6_iface_scope_id(&sin->sin6_addr, 502 IP6CB(skb)->iif); 503 } else { 504 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr, 505 &sin->sin6_addr); 506 if (inet_sk(sk)->cmsg_flags) 507 ip_cmsg_recv(msg, skb); 508 } 509 } 510 511 put_cmsg(msg, SOL_IPV6, IPV6_RECVERR, sizeof(errhdr), &errhdr); 512 513 /* Now we could try to dump offended packet options */ 514 515 msg->msg_flags |= MSG_ERRQUEUE; 516 err = copied; 517 518 consume_skb(skb); 519 out: 520 return err; 521 } 522 EXPORT_SYMBOL_GPL(ipv6_recv_error); 523 524 /* 525 * Handle IPV6_RECVPATHMTU 526 */ 527 int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len, 528 int *addr_len) 529 { 530 struct ipv6_pinfo *np = inet6_sk(sk); 531 struct sk_buff *skb; 532 struct ip6_mtuinfo mtu_info; 533 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name); 534 int err; 535 int copied; 536 537 err = -EAGAIN; 538 skb = xchg(&np->rxpmtu, NULL); 539 if (!skb) 540 goto out; 541 542 copied = skb->len; 543 if (copied > len) { 544 msg->msg_flags |= MSG_TRUNC; 545 copied = len; 546 } 547 err = skb_copy_datagram_msg(skb, 0, msg, copied); 548 if (err) 549 goto out_free_skb; 550 551 sock_recv_timestamp(msg, sk, skb); 552 553 memcpy(&mtu_info, IP6CBMTU(skb), sizeof(mtu_info)); 554 555 if (sin) { 556 sin->sin6_family = AF_INET6; 557 sin->sin6_flowinfo = 0; 558 sin->sin6_port = 0; 559 sin->sin6_scope_id = mtu_info.ip6m_addr.sin6_scope_id; 560 sin->sin6_addr = mtu_info.ip6m_addr.sin6_addr; 561 *addr_len = sizeof(*sin); 562 } 563 564 put_cmsg(msg, SOL_IPV6, IPV6_PATHMTU, sizeof(mtu_info), &mtu_info); 565 566 err = copied; 567 568 out_free_skb: 569 kfree_skb(skb); 570 out: 571 return err; 572 } 573 574 575 void ip6_datagram_recv_common_ctl(struct sock *sk, struct msghdr *msg, 576 struct sk_buff *skb) 577 { 578 struct ipv6_pinfo *np = inet6_sk(sk); 579 bool is_ipv6 = skb->protocol == htons(ETH_P_IPV6); 580 581 if (np->rxopt.bits.rxinfo) { 582 struct in6_pktinfo src_info; 583 584 if (is_ipv6) { 585 src_info.ipi6_ifindex = IP6CB(skb)->iif; 586 src_info.ipi6_addr = ipv6_hdr(skb)->daddr; 587 } else { 588 src_info.ipi6_ifindex = 589 PKTINFO_SKB_CB(skb)->ipi_ifindex; 590 ipv6_addr_set_v4mapped(ip_hdr(skb)->daddr, 591 &src_info.ipi6_addr); 592 } 593 594 if (src_info.ipi6_ifindex >= 0) 595 put_cmsg(msg, SOL_IPV6, IPV6_PKTINFO, 596 sizeof(src_info), &src_info); 597 } 598 } 599 600 void ip6_datagram_recv_specific_ctl(struct sock *sk, struct msghdr *msg, 601 struct sk_buff *skb) 602 { 603 struct ipv6_pinfo *np = inet6_sk(sk); 604 struct inet6_skb_parm *opt = IP6CB(skb); 605 unsigned char *nh = skb_network_header(skb); 606 607 if (np->rxopt.bits.rxhlim) { 608 int hlim = ipv6_hdr(skb)->hop_limit; 609 put_cmsg(msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim); 610 } 611 612 if (np->rxopt.bits.rxtclass) { 613 int tclass = ipv6_get_dsfield(ipv6_hdr(skb)); 614 put_cmsg(msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass); 615 } 616 617 if (np->rxopt.bits.rxflow) { 618 __be32 flowinfo = ip6_flowinfo((struct ipv6hdr *)nh); 619 if (flowinfo) 620 put_cmsg(msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo); 621 } 622 623 /* HbH is allowed only once */ 624 if (np->rxopt.bits.hopopts && (opt->flags & IP6SKB_HOPBYHOP)) { 625 u8 *ptr = nh + sizeof(struct ipv6hdr); 626 put_cmsg(msg, SOL_IPV6, IPV6_HOPOPTS, (ptr[1]+1)<<3, ptr); 627 } 628 629 if (opt->lastopt && 630 (np->rxopt.bits.dstopts || np->rxopt.bits.srcrt)) { 631 /* 632 * Silly enough, but we need to reparse in order to 633 * report extension headers (except for HbH) 634 * in order. 635 * 636 * Also note that IPV6_RECVRTHDRDSTOPTS is NOT 637 * (and WILL NOT be) defined because 638 * IPV6_RECVDSTOPTS is more generic. --yoshfuji 639 */ 640 unsigned int off = sizeof(struct ipv6hdr); 641 u8 nexthdr = ipv6_hdr(skb)->nexthdr; 642 643 while (off <= opt->lastopt) { 644 unsigned int len; 645 u8 *ptr = nh + off; 646 647 switch (nexthdr) { 648 case IPPROTO_DSTOPTS: 649 nexthdr = ptr[0]; 650 len = (ptr[1] + 1) << 3; 651 if (np->rxopt.bits.dstopts) 652 put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, len, ptr); 653 break; 654 case IPPROTO_ROUTING: 655 nexthdr = ptr[0]; 656 len = (ptr[1] + 1) << 3; 657 if (np->rxopt.bits.srcrt) 658 put_cmsg(msg, SOL_IPV6, IPV6_RTHDR, len, ptr); 659 break; 660 case IPPROTO_AH: 661 nexthdr = ptr[0]; 662 len = (ptr[1] + 2) << 2; 663 break; 664 default: 665 nexthdr = ptr[0]; 666 len = (ptr[1] + 1) << 3; 667 break; 668 } 669 670 off += len; 671 } 672 } 673 674 /* socket options in old style */ 675 if (np->rxopt.bits.rxoinfo) { 676 struct in6_pktinfo src_info; 677 678 src_info.ipi6_ifindex = opt->iif; 679 src_info.ipi6_addr = ipv6_hdr(skb)->daddr; 680 put_cmsg(msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info); 681 } 682 if (np->rxopt.bits.rxohlim) { 683 int hlim = ipv6_hdr(skb)->hop_limit; 684 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim); 685 } 686 if (np->rxopt.bits.ohopopts && (opt->flags & IP6SKB_HOPBYHOP)) { 687 u8 *ptr = nh + sizeof(struct ipv6hdr); 688 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPOPTS, (ptr[1]+1)<<3, ptr); 689 } 690 if (np->rxopt.bits.odstopts && opt->dst0) { 691 u8 *ptr = nh + opt->dst0; 692 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr); 693 } 694 if (np->rxopt.bits.osrcrt && opt->srcrt) { 695 struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(nh + opt->srcrt); 696 put_cmsg(msg, SOL_IPV6, IPV6_2292RTHDR, (rthdr->hdrlen+1) << 3, rthdr); 697 } 698 if (np->rxopt.bits.odstopts && opt->dst1) { 699 u8 *ptr = nh + opt->dst1; 700 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr); 701 } 702 if (np->rxopt.bits.rxorigdstaddr) { 703 struct sockaddr_in6 sin6; 704 __be16 *ports = (__be16 *) skb_transport_header(skb); 705 706 if (skb_transport_offset(skb) + 4 <= (int)skb->len) { 707 /* All current transport protocols have the port numbers in the 708 * first four bytes of the transport header and this function is 709 * written with this assumption in mind. 710 */ 711 712 sin6.sin6_family = AF_INET6; 713 sin6.sin6_addr = ipv6_hdr(skb)->daddr; 714 sin6.sin6_port = ports[1]; 715 sin6.sin6_flowinfo = 0; 716 sin6.sin6_scope_id = 717 ipv6_iface_scope_id(&ipv6_hdr(skb)->daddr, 718 opt->iif); 719 720 put_cmsg(msg, SOL_IPV6, IPV6_ORIGDSTADDR, sizeof(sin6), &sin6); 721 } 722 } 723 if (np->rxopt.bits.recvfragsize && opt->frag_max_size) { 724 int val = opt->frag_max_size; 725 726 put_cmsg(msg, SOL_IPV6, IPV6_RECVFRAGSIZE, sizeof(val), &val); 727 } 728 } 729 730 void ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg, 731 struct sk_buff *skb) 732 { 733 ip6_datagram_recv_common_ctl(sk, msg, skb); 734 ip6_datagram_recv_specific_ctl(sk, msg, skb); 735 } 736 EXPORT_SYMBOL_GPL(ip6_datagram_recv_ctl); 737 738 int ip6_datagram_send_ctl(struct net *net, struct sock *sk, 739 struct msghdr *msg, struct flowi6 *fl6, 740 struct ipcm6_cookie *ipc6, struct sockcm_cookie *sockc) 741 { 742 struct in6_pktinfo *src_info; 743 struct cmsghdr *cmsg; 744 struct ipv6_rt_hdr *rthdr; 745 struct ipv6_opt_hdr *hdr; 746 struct ipv6_txoptions *opt = ipc6->opt; 747 int len; 748 int err = 0; 749 750 for_each_cmsghdr(cmsg, msg) { 751 int addr_type; 752 753 if (!CMSG_OK(msg, cmsg)) { 754 err = -EINVAL; 755 goto exit_f; 756 } 757 758 if (cmsg->cmsg_level == SOL_SOCKET) { 759 err = __sock_cmsg_send(sk, msg, cmsg, sockc); 760 if (err) 761 return err; 762 continue; 763 } 764 765 if (cmsg->cmsg_level != SOL_IPV6) 766 continue; 767 768 switch (cmsg->cmsg_type) { 769 case IPV6_PKTINFO: 770 case IPV6_2292PKTINFO: 771 { 772 struct net_device *dev = NULL; 773 774 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct in6_pktinfo))) { 775 err = -EINVAL; 776 goto exit_f; 777 } 778 779 src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg); 780 781 if (src_info->ipi6_ifindex) { 782 if (fl6->flowi6_oif && 783 src_info->ipi6_ifindex != fl6->flowi6_oif) 784 return -EINVAL; 785 fl6->flowi6_oif = src_info->ipi6_ifindex; 786 } 787 788 addr_type = __ipv6_addr_type(&src_info->ipi6_addr); 789 790 rcu_read_lock(); 791 if (fl6->flowi6_oif) { 792 dev = dev_get_by_index_rcu(net, fl6->flowi6_oif); 793 if (!dev) { 794 rcu_read_unlock(); 795 return -ENODEV; 796 } 797 } else if (addr_type & IPV6_ADDR_LINKLOCAL) { 798 rcu_read_unlock(); 799 return -EINVAL; 800 } 801 802 if (addr_type != IPV6_ADDR_ANY) { 803 int strict = __ipv6_addr_src_scope(addr_type) <= IPV6_ADDR_SCOPE_LINKLOCAL; 804 if (!(inet_sk(sk)->freebind || inet_sk(sk)->transparent) && 805 !ipv6_chk_addr(net, &src_info->ipi6_addr, 806 strict ? dev : NULL, 0) && 807 !ipv6_chk_acast_addr_src(net, dev, 808 &src_info->ipi6_addr)) 809 err = -EINVAL; 810 else 811 fl6->saddr = src_info->ipi6_addr; 812 } 813 814 rcu_read_unlock(); 815 816 if (err) 817 goto exit_f; 818 819 break; 820 } 821 822 case IPV6_FLOWINFO: 823 if (cmsg->cmsg_len < CMSG_LEN(4)) { 824 err = -EINVAL; 825 goto exit_f; 826 } 827 828 if (fl6->flowlabel&IPV6_FLOWINFO_MASK) { 829 if ((fl6->flowlabel^*(__be32 *)CMSG_DATA(cmsg))&~IPV6_FLOWINFO_MASK) { 830 err = -EINVAL; 831 goto exit_f; 832 } 833 } 834 fl6->flowlabel = IPV6_FLOWINFO_MASK & *(__be32 *)CMSG_DATA(cmsg); 835 break; 836 837 case IPV6_2292HOPOPTS: 838 case IPV6_HOPOPTS: 839 if (opt->hopopt || cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) { 840 err = -EINVAL; 841 goto exit_f; 842 } 843 844 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg); 845 len = ((hdr->hdrlen + 1) << 3); 846 if (cmsg->cmsg_len < CMSG_LEN(len)) { 847 err = -EINVAL; 848 goto exit_f; 849 } 850 if (!ns_capable(net->user_ns, CAP_NET_RAW)) { 851 err = -EPERM; 852 goto exit_f; 853 } 854 opt->opt_nflen += len; 855 opt->hopopt = hdr; 856 break; 857 858 case IPV6_2292DSTOPTS: 859 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) { 860 err = -EINVAL; 861 goto exit_f; 862 } 863 864 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg); 865 len = ((hdr->hdrlen + 1) << 3); 866 if (cmsg->cmsg_len < CMSG_LEN(len)) { 867 err = -EINVAL; 868 goto exit_f; 869 } 870 if (!ns_capable(net->user_ns, CAP_NET_RAW)) { 871 err = -EPERM; 872 goto exit_f; 873 } 874 if (opt->dst1opt) { 875 err = -EINVAL; 876 goto exit_f; 877 } 878 opt->opt_flen += len; 879 opt->dst1opt = hdr; 880 break; 881 882 case IPV6_DSTOPTS: 883 case IPV6_RTHDRDSTOPTS: 884 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) { 885 err = -EINVAL; 886 goto exit_f; 887 } 888 889 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg); 890 len = ((hdr->hdrlen + 1) << 3); 891 if (cmsg->cmsg_len < CMSG_LEN(len)) { 892 err = -EINVAL; 893 goto exit_f; 894 } 895 if (!ns_capable(net->user_ns, CAP_NET_RAW)) { 896 err = -EPERM; 897 goto exit_f; 898 } 899 if (cmsg->cmsg_type == IPV6_DSTOPTS) { 900 opt->opt_flen += len; 901 opt->dst1opt = hdr; 902 } else { 903 opt->opt_nflen += len; 904 opt->dst0opt = hdr; 905 } 906 break; 907 908 case IPV6_2292RTHDR: 909 case IPV6_RTHDR: 910 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_rt_hdr))) { 911 err = -EINVAL; 912 goto exit_f; 913 } 914 915 rthdr = (struct ipv6_rt_hdr *)CMSG_DATA(cmsg); 916 917 switch (rthdr->type) { 918 #if IS_ENABLED(CONFIG_IPV6_MIP6) 919 case IPV6_SRCRT_TYPE_2: 920 if (rthdr->hdrlen != 2 || 921 rthdr->segments_left != 1) { 922 err = -EINVAL; 923 goto exit_f; 924 } 925 break; 926 #endif 927 default: 928 err = -EINVAL; 929 goto exit_f; 930 } 931 932 len = ((rthdr->hdrlen + 1) << 3); 933 934 if (cmsg->cmsg_len < CMSG_LEN(len)) { 935 err = -EINVAL; 936 goto exit_f; 937 } 938 939 /* segments left must also match */ 940 if ((rthdr->hdrlen >> 1) != rthdr->segments_left) { 941 err = -EINVAL; 942 goto exit_f; 943 } 944 945 opt->opt_nflen += len; 946 opt->srcrt = rthdr; 947 948 if (cmsg->cmsg_type == IPV6_2292RTHDR && opt->dst1opt) { 949 int dsthdrlen = ((opt->dst1opt->hdrlen+1)<<3); 950 951 opt->opt_nflen += dsthdrlen; 952 opt->dst0opt = opt->dst1opt; 953 opt->dst1opt = NULL; 954 opt->opt_flen -= dsthdrlen; 955 } 956 957 break; 958 959 case IPV6_2292HOPLIMIT: 960 case IPV6_HOPLIMIT: 961 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) { 962 err = -EINVAL; 963 goto exit_f; 964 } 965 966 ipc6->hlimit = *(int *)CMSG_DATA(cmsg); 967 if (ipc6->hlimit < -1 || ipc6->hlimit > 0xff) { 968 err = -EINVAL; 969 goto exit_f; 970 } 971 972 break; 973 974 case IPV6_TCLASS: 975 { 976 int tc; 977 978 err = -EINVAL; 979 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) 980 goto exit_f; 981 982 tc = *(int *)CMSG_DATA(cmsg); 983 if (tc < -1 || tc > 0xff) 984 goto exit_f; 985 986 err = 0; 987 ipc6->tclass = tc; 988 989 break; 990 } 991 992 case IPV6_DONTFRAG: 993 { 994 int df; 995 996 err = -EINVAL; 997 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) 998 goto exit_f; 999 1000 df = *(int *)CMSG_DATA(cmsg); 1001 if (df < 0 || df > 1) 1002 goto exit_f; 1003 1004 err = 0; 1005 ipc6->dontfrag = df; 1006 1007 break; 1008 } 1009 default: 1010 net_dbg_ratelimited("invalid cmsg type: %d\n", 1011 cmsg->cmsg_type); 1012 err = -EINVAL; 1013 goto exit_f; 1014 } 1015 } 1016 1017 exit_f: 1018 return err; 1019 } 1020 EXPORT_SYMBOL_GPL(ip6_datagram_send_ctl); 1021 1022 void ip6_dgram_sock_seq_show(struct seq_file *seq, struct sock *sp, 1023 __u16 srcp, __u16 destp, int bucket) 1024 { 1025 const struct in6_addr *dest, *src; 1026 1027 dest = &sp->sk_v6_daddr; 1028 src = &sp->sk_v6_rcv_saddr; 1029 seq_printf(seq, 1030 "%5d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " 1031 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %d\n", 1032 bucket, 1033 src->s6_addr32[0], src->s6_addr32[1], 1034 src->s6_addr32[2], src->s6_addr32[3], srcp, 1035 dest->s6_addr32[0], dest->s6_addr32[1], 1036 dest->s6_addr32[2], dest->s6_addr32[3], destp, 1037 sp->sk_state, 1038 sk_wmem_alloc_get(sp), 1039 sk_rmem_alloc_get(sp), 1040 0, 0L, 0, 1041 from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)), 1042 0, 1043 sock_i_ino(sp), 1044 refcount_read(&sp->sk_refcnt), sp, 1045 atomic_read(&sp->sk_drops)); 1046 } 1047