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 ip6_flow_hdr(iph, 0, 0); 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[2], *ports; 705 706 ports = skb_header_pointer(skb, skb_transport_offset(skb), 707 sizeof(_ports), &_ports); 708 if (ports) { 709 /* All current transport protocols have the port numbers in the 710 * first four bytes of the transport header and this function is 711 * written with this assumption in mind. 712 */ 713 sin6.sin6_family = AF_INET6; 714 sin6.sin6_addr = ipv6_hdr(skb)->daddr; 715 sin6.sin6_port = ports[1]; 716 sin6.sin6_flowinfo = 0; 717 sin6.sin6_scope_id = 718 ipv6_iface_scope_id(&ipv6_hdr(skb)->daddr, 719 opt->iif); 720 721 put_cmsg(msg, SOL_IPV6, IPV6_ORIGDSTADDR, sizeof(sin6), &sin6); 722 } 723 } 724 if (np->rxopt.bits.recvfragsize && opt->frag_max_size) { 725 int val = opt->frag_max_size; 726 727 put_cmsg(msg, SOL_IPV6, IPV6_RECVFRAGSIZE, sizeof(val), &val); 728 } 729 } 730 731 void ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg, 732 struct sk_buff *skb) 733 { 734 ip6_datagram_recv_common_ctl(sk, msg, skb); 735 ip6_datagram_recv_specific_ctl(sk, msg, skb); 736 } 737 EXPORT_SYMBOL_GPL(ip6_datagram_recv_ctl); 738 739 int ip6_datagram_send_ctl(struct net *net, struct sock *sk, 740 struct msghdr *msg, struct flowi6 *fl6, 741 struct ipcm6_cookie *ipc6) 742 { 743 struct in6_pktinfo *src_info; 744 struct cmsghdr *cmsg; 745 struct ipv6_rt_hdr *rthdr; 746 struct ipv6_opt_hdr *hdr; 747 struct ipv6_txoptions *opt = ipc6->opt; 748 int len; 749 int err = 0; 750 751 for_each_cmsghdr(cmsg, msg) { 752 int addr_type; 753 754 if (!CMSG_OK(msg, cmsg)) { 755 err = -EINVAL; 756 goto exit_f; 757 } 758 759 if (cmsg->cmsg_level == SOL_SOCKET) { 760 err = __sock_cmsg_send(sk, msg, cmsg, &ipc6->sockc); 761 if (err) 762 return err; 763 continue; 764 } 765 766 if (cmsg->cmsg_level != SOL_IPV6) 767 continue; 768 769 switch (cmsg->cmsg_type) { 770 case IPV6_PKTINFO: 771 case IPV6_2292PKTINFO: 772 { 773 struct net_device *dev = NULL; 774 int src_idx; 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 src_idx = src_info->ipi6_ifindex; 783 784 if (src_idx) { 785 if (fl6->flowi6_oif && 786 src_idx != fl6->flowi6_oif && 787 (sk->sk_bound_dev_if != fl6->flowi6_oif || 788 !sk_dev_equal_l3scope(sk, src_idx))) 789 return -EINVAL; 790 fl6->flowi6_oif = src_idx; 791 } 792 793 addr_type = __ipv6_addr_type(&src_info->ipi6_addr); 794 795 rcu_read_lock(); 796 if (fl6->flowi6_oif) { 797 dev = dev_get_by_index_rcu(net, fl6->flowi6_oif); 798 if (!dev) { 799 rcu_read_unlock(); 800 return -ENODEV; 801 } 802 } else if (addr_type & IPV6_ADDR_LINKLOCAL) { 803 rcu_read_unlock(); 804 return -EINVAL; 805 } 806 807 if (addr_type != IPV6_ADDR_ANY) { 808 int strict = __ipv6_addr_src_scope(addr_type) <= IPV6_ADDR_SCOPE_LINKLOCAL; 809 if (!ipv6_can_nonlocal_bind(net, inet_sk(sk)) && 810 !ipv6_chk_addr_and_flags(net, &src_info->ipi6_addr, 811 dev, !strict, 0, 812 IFA_F_TENTATIVE) && 813 !ipv6_chk_acast_addr_src(net, dev, 814 &src_info->ipi6_addr)) 815 err = -EINVAL; 816 else 817 fl6->saddr = src_info->ipi6_addr; 818 } 819 820 rcu_read_unlock(); 821 822 if (err) 823 goto exit_f; 824 825 break; 826 } 827 828 case IPV6_FLOWINFO: 829 if (cmsg->cmsg_len < CMSG_LEN(4)) { 830 err = -EINVAL; 831 goto exit_f; 832 } 833 834 if (fl6->flowlabel&IPV6_FLOWINFO_MASK) { 835 if ((fl6->flowlabel^*(__be32 *)CMSG_DATA(cmsg))&~IPV6_FLOWINFO_MASK) { 836 err = -EINVAL; 837 goto exit_f; 838 } 839 } 840 fl6->flowlabel = IPV6_FLOWINFO_MASK & *(__be32 *)CMSG_DATA(cmsg); 841 break; 842 843 case IPV6_2292HOPOPTS: 844 case IPV6_HOPOPTS: 845 if (opt->hopopt || cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) { 846 err = -EINVAL; 847 goto exit_f; 848 } 849 850 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg); 851 len = ((hdr->hdrlen + 1) << 3); 852 if (cmsg->cmsg_len < CMSG_LEN(len)) { 853 err = -EINVAL; 854 goto exit_f; 855 } 856 if (!ns_capable(net->user_ns, CAP_NET_RAW)) { 857 err = -EPERM; 858 goto exit_f; 859 } 860 opt->opt_nflen += len; 861 opt->hopopt = hdr; 862 break; 863 864 case IPV6_2292DSTOPTS: 865 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) { 866 err = -EINVAL; 867 goto exit_f; 868 } 869 870 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg); 871 len = ((hdr->hdrlen + 1) << 3); 872 if (cmsg->cmsg_len < CMSG_LEN(len)) { 873 err = -EINVAL; 874 goto exit_f; 875 } 876 if (!ns_capable(net->user_ns, CAP_NET_RAW)) { 877 err = -EPERM; 878 goto exit_f; 879 } 880 if (opt->dst1opt) { 881 err = -EINVAL; 882 goto exit_f; 883 } 884 opt->opt_flen += len; 885 opt->dst1opt = hdr; 886 break; 887 888 case IPV6_DSTOPTS: 889 case IPV6_RTHDRDSTOPTS: 890 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) { 891 err = -EINVAL; 892 goto exit_f; 893 } 894 895 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg); 896 len = ((hdr->hdrlen + 1) << 3); 897 if (cmsg->cmsg_len < CMSG_LEN(len)) { 898 err = -EINVAL; 899 goto exit_f; 900 } 901 if (!ns_capable(net->user_ns, CAP_NET_RAW)) { 902 err = -EPERM; 903 goto exit_f; 904 } 905 if (cmsg->cmsg_type == IPV6_DSTOPTS) { 906 opt->opt_flen += len; 907 opt->dst1opt = hdr; 908 } else { 909 opt->opt_nflen += len; 910 opt->dst0opt = hdr; 911 } 912 break; 913 914 case IPV6_2292RTHDR: 915 case IPV6_RTHDR: 916 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_rt_hdr))) { 917 err = -EINVAL; 918 goto exit_f; 919 } 920 921 rthdr = (struct ipv6_rt_hdr *)CMSG_DATA(cmsg); 922 923 switch (rthdr->type) { 924 #if IS_ENABLED(CONFIG_IPV6_MIP6) 925 case IPV6_SRCRT_TYPE_2: 926 if (rthdr->hdrlen != 2 || 927 rthdr->segments_left != 1) { 928 err = -EINVAL; 929 goto exit_f; 930 } 931 break; 932 #endif 933 default: 934 err = -EINVAL; 935 goto exit_f; 936 } 937 938 len = ((rthdr->hdrlen + 1) << 3); 939 940 if (cmsg->cmsg_len < CMSG_LEN(len)) { 941 err = -EINVAL; 942 goto exit_f; 943 } 944 945 /* segments left must also match */ 946 if ((rthdr->hdrlen >> 1) != rthdr->segments_left) { 947 err = -EINVAL; 948 goto exit_f; 949 } 950 951 opt->opt_nflen += len; 952 opt->srcrt = rthdr; 953 954 if (cmsg->cmsg_type == IPV6_2292RTHDR && opt->dst1opt) { 955 int dsthdrlen = ((opt->dst1opt->hdrlen+1)<<3); 956 957 opt->opt_nflen += dsthdrlen; 958 opt->dst0opt = opt->dst1opt; 959 opt->dst1opt = NULL; 960 opt->opt_flen -= dsthdrlen; 961 } 962 963 break; 964 965 case IPV6_2292HOPLIMIT: 966 case IPV6_HOPLIMIT: 967 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) { 968 err = -EINVAL; 969 goto exit_f; 970 } 971 972 ipc6->hlimit = *(int *)CMSG_DATA(cmsg); 973 if (ipc6->hlimit < -1 || ipc6->hlimit > 0xff) { 974 err = -EINVAL; 975 goto exit_f; 976 } 977 978 break; 979 980 case IPV6_TCLASS: 981 { 982 int tc; 983 984 err = -EINVAL; 985 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) 986 goto exit_f; 987 988 tc = *(int *)CMSG_DATA(cmsg); 989 if (tc < -1 || tc > 0xff) 990 goto exit_f; 991 992 err = 0; 993 ipc6->tclass = tc; 994 995 break; 996 } 997 998 case IPV6_DONTFRAG: 999 { 1000 int df; 1001 1002 err = -EINVAL; 1003 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) 1004 goto exit_f; 1005 1006 df = *(int *)CMSG_DATA(cmsg); 1007 if (df < 0 || df > 1) 1008 goto exit_f; 1009 1010 err = 0; 1011 ipc6->dontfrag = df; 1012 1013 break; 1014 } 1015 default: 1016 net_dbg_ratelimited("invalid cmsg type: %d\n", 1017 cmsg->cmsg_type); 1018 err = -EINVAL; 1019 goto exit_f; 1020 } 1021 } 1022 1023 exit_f: 1024 return err; 1025 } 1026 EXPORT_SYMBOL_GPL(ip6_datagram_send_ctl); 1027 1028 void __ip6_dgram_sock_seq_show(struct seq_file *seq, struct sock *sp, 1029 __u16 srcp, __u16 destp, int rqueue, int bucket) 1030 { 1031 const struct in6_addr *dest, *src; 1032 1033 dest = &sp->sk_v6_daddr; 1034 src = &sp->sk_v6_rcv_saddr; 1035 seq_printf(seq, 1036 "%5d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " 1037 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %d\n", 1038 bucket, 1039 src->s6_addr32[0], src->s6_addr32[1], 1040 src->s6_addr32[2], src->s6_addr32[3], srcp, 1041 dest->s6_addr32[0], dest->s6_addr32[1], 1042 dest->s6_addr32[2], dest->s6_addr32[3], destp, 1043 sp->sk_state, 1044 sk_wmem_alloc_get(sp), 1045 rqueue, 1046 0, 0L, 0, 1047 from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)), 1048 0, 1049 sock_i_ino(sp), 1050 refcount_read(&sp->sk_refcnt), sp, 1051 atomic_read(&sp->sk_drops)); 1052 } 1053