1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * common UDP/RAW code 4 * Linux INET6 implementation 5 * 6 * Authors: 7 * Pedro Roque <roque@di.fc.ul.pt> 8 */ 9 10 #include <linux/capability.h> 11 #include <linux/errno.h> 12 #include <linux/types.h> 13 #include <linux/kernel.h> 14 #include <linux/interrupt.h> 15 #include <linux/socket.h> 16 #include <linux/sockios.h> 17 #include <linux/in6.h> 18 #include <linux/ipv6.h> 19 #include <linux/route.h> 20 #include <linux/slab.h> 21 #include <linux/export.h> 22 #include <linux/icmp.h> 23 24 #include <net/ipv6.h> 25 #include <net/ndisc.h> 26 #include <net/addrconf.h> 27 #include <net/transp_v6.h> 28 #include <net/ip6_route.h> 29 #include <net/tcp_states.h> 30 #include <net/dsfield.h> 31 #include <net/sock_reuseport.h> 32 33 #include <linux/errqueue.h> 34 #include <linux/uaccess.h> 35 36 static bool ipv6_mapped_addr_any(const struct in6_addr *a) 37 { 38 return ipv6_addr_v4mapped(a) && (a->s6_addr32[3] == 0); 39 } 40 41 static void ip6_datagram_flow_key_init(struct flowi6 *fl6, struct sock *sk) 42 { 43 struct inet_sock *inet = inet_sk(sk); 44 struct ipv6_pinfo *np = inet6_sk(sk); 45 46 memset(fl6, 0, sizeof(*fl6)); 47 fl6->flowi6_proto = sk->sk_protocol; 48 fl6->daddr = sk->sk_v6_daddr; 49 fl6->saddr = np->saddr; 50 fl6->flowi6_oif = sk->sk_bound_dev_if; 51 fl6->flowi6_mark = sk->sk_mark; 52 fl6->fl6_dport = inet->inet_dport; 53 fl6->fl6_sport = inet->inet_sport; 54 fl6->flowlabel = np->flow_label; 55 fl6->flowi6_uid = sk->sk_uid; 56 57 if (!fl6->flowi6_oif) 58 fl6->flowi6_oif = np->sticky_pktinfo.ipi6_ifindex; 59 60 if (!fl6->flowi6_oif && ipv6_addr_is_multicast(&fl6->daddr)) 61 fl6->flowi6_oif = np->mcast_oif; 62 63 security_sk_classify_flow(sk, flowi6_to_flowi_common(fl6)); 64 } 65 66 int ip6_datagram_dst_update(struct sock *sk, bool fix_sk_saddr) 67 { 68 struct ip6_flowlabel *flowlabel = NULL; 69 struct in6_addr *final_p, final; 70 struct ipv6_txoptions *opt; 71 struct dst_entry *dst; 72 struct inet_sock *inet = inet_sk(sk); 73 struct ipv6_pinfo *np = inet6_sk(sk); 74 struct flowi6 fl6; 75 int err = 0; 76 77 if (np->sndflow && (np->flow_label & IPV6_FLOWLABEL_MASK)) { 78 flowlabel = fl6_sock_lookup(sk, np->flow_label); 79 if (IS_ERR(flowlabel)) 80 return -EINVAL; 81 } 82 ip6_datagram_flow_key_init(&fl6, sk); 83 84 rcu_read_lock(); 85 opt = flowlabel ? flowlabel->opt : rcu_dereference(np->opt); 86 final_p = fl6_update_dst(&fl6, opt, &final); 87 rcu_read_unlock(); 88 89 dst = ip6_dst_lookup_flow(sock_net(sk), sk, &fl6, final_p); 90 if (IS_ERR(dst)) { 91 err = PTR_ERR(dst); 92 goto out; 93 } 94 95 if (fix_sk_saddr) { 96 if (ipv6_addr_any(&np->saddr)) 97 np->saddr = fl6.saddr; 98 99 if (ipv6_addr_any(&sk->sk_v6_rcv_saddr)) { 100 sk->sk_v6_rcv_saddr = fl6.saddr; 101 inet->inet_rcv_saddr = LOOPBACK4_IPV6; 102 if (sk->sk_prot->rehash) 103 sk->sk_prot->rehash(sk); 104 } 105 } 106 107 ip6_sk_dst_store_flow(sk, dst, &fl6); 108 109 out: 110 fl6_sock_release(flowlabel); 111 return err; 112 } 113 114 void ip6_datagram_release_cb(struct sock *sk) 115 { 116 struct dst_entry *dst; 117 118 if (ipv6_addr_v4mapped(&sk->sk_v6_daddr)) 119 return; 120 121 rcu_read_lock(); 122 dst = __sk_dst_get(sk); 123 if (!dst || !dst->obsolete || 124 dst->ops->check(dst, inet6_sk(sk)->dst_cookie)) { 125 rcu_read_unlock(); 126 return; 127 } 128 rcu_read_unlock(); 129 130 ip6_datagram_dst_update(sk, false); 131 } 132 EXPORT_SYMBOL_GPL(ip6_datagram_release_cb); 133 134 int __ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, 135 int addr_len) 136 { 137 struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr; 138 struct inet_sock *inet = inet_sk(sk); 139 struct ipv6_pinfo *np = inet6_sk(sk); 140 struct in6_addr *daddr, old_daddr; 141 __be32 fl6_flowlabel = 0; 142 __be32 old_fl6_flowlabel; 143 __be16 old_dport; 144 int addr_type; 145 int err; 146 147 if (usin->sin6_family == AF_INET) { 148 if (ipv6_only_sock(sk)) 149 return -EAFNOSUPPORT; 150 err = __ip4_datagram_connect(sk, uaddr, addr_len); 151 goto ipv4_connected; 152 } 153 154 if (addr_len < SIN6_LEN_RFC2133) 155 return -EINVAL; 156 157 if (usin->sin6_family != AF_INET6) 158 return -EAFNOSUPPORT; 159 160 if (np->sndflow) 161 fl6_flowlabel = usin->sin6_flowinfo & IPV6_FLOWINFO_MASK; 162 163 if (ipv6_addr_any(&usin->sin6_addr)) { 164 /* 165 * connect to self 166 */ 167 if (ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr)) 168 ipv6_addr_set_v4mapped(htonl(INADDR_LOOPBACK), 169 &usin->sin6_addr); 170 else 171 usin->sin6_addr = in6addr_loopback; 172 } 173 174 addr_type = ipv6_addr_type(&usin->sin6_addr); 175 176 daddr = &usin->sin6_addr; 177 178 if (addr_type & IPV6_ADDR_MAPPED) { 179 struct sockaddr_in sin; 180 181 if (ipv6_only_sock(sk)) { 182 err = -ENETUNREACH; 183 goto out; 184 } 185 sin.sin_family = AF_INET; 186 sin.sin_addr.s_addr = daddr->s6_addr32[3]; 187 sin.sin_port = usin->sin6_port; 188 189 err = __ip4_datagram_connect(sk, 190 (struct sockaddr *) &sin, 191 sizeof(sin)); 192 193 ipv4_connected: 194 if (err) 195 goto out; 196 197 ipv6_addr_set_v4mapped(inet->inet_daddr, &sk->sk_v6_daddr); 198 199 if (ipv6_addr_any(&np->saddr) || 200 ipv6_mapped_addr_any(&np->saddr)) 201 ipv6_addr_set_v4mapped(inet->inet_saddr, &np->saddr); 202 203 if (ipv6_addr_any(&sk->sk_v6_rcv_saddr) || 204 ipv6_mapped_addr_any(&sk->sk_v6_rcv_saddr)) { 205 ipv6_addr_set_v4mapped(inet->inet_rcv_saddr, 206 &sk->sk_v6_rcv_saddr); 207 if (sk->sk_prot->rehash) 208 sk->sk_prot->rehash(sk); 209 } 210 211 goto out; 212 } 213 214 if (__ipv6_addr_needs_scope_id(addr_type)) { 215 if (addr_len >= sizeof(struct sockaddr_in6) && 216 usin->sin6_scope_id) { 217 if (!sk_dev_equal_l3scope(sk, usin->sin6_scope_id)) { 218 err = -EINVAL; 219 goto out; 220 } 221 WRITE_ONCE(sk->sk_bound_dev_if, usin->sin6_scope_id); 222 } 223 224 if (!sk->sk_bound_dev_if && (addr_type & IPV6_ADDR_MULTICAST)) 225 WRITE_ONCE(sk->sk_bound_dev_if, np->mcast_oif); 226 227 /* Connect to link-local address requires an interface */ 228 if (!sk->sk_bound_dev_if) { 229 err = -EINVAL; 230 goto out; 231 } 232 } 233 234 /* save the current peer information before updating it */ 235 old_daddr = sk->sk_v6_daddr; 236 old_fl6_flowlabel = np->flow_label; 237 old_dport = inet->inet_dport; 238 239 sk->sk_v6_daddr = *daddr; 240 np->flow_label = fl6_flowlabel; 241 inet->inet_dport = usin->sin6_port; 242 243 /* 244 * Check for a route to destination an obtain the 245 * destination cache for it. 246 */ 247 248 err = ip6_datagram_dst_update(sk, true); 249 if (err) { 250 /* Restore the socket peer info, to keep it consistent with 251 * the old socket state 252 */ 253 sk->sk_v6_daddr = old_daddr; 254 np->flow_label = old_fl6_flowlabel; 255 inet->inet_dport = old_dport; 256 goto out; 257 } 258 259 reuseport_has_conns_set(sk); 260 sk->sk_state = TCP_ESTABLISHED; 261 sk_set_txhash(sk); 262 out: 263 return err; 264 } 265 EXPORT_SYMBOL_GPL(__ip6_datagram_connect); 266 267 int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) 268 { 269 int res; 270 271 lock_sock(sk); 272 res = __ip6_datagram_connect(sk, uaddr, addr_len); 273 release_sock(sk); 274 return res; 275 } 276 EXPORT_SYMBOL_GPL(ip6_datagram_connect); 277 278 int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *uaddr, 279 int addr_len) 280 { 281 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, uaddr); 282 if (sin6->sin6_family != AF_INET6) 283 return -EAFNOSUPPORT; 284 return ip6_datagram_connect(sk, uaddr, addr_len); 285 } 286 EXPORT_SYMBOL_GPL(ip6_datagram_connect_v6_only); 287 288 static void ipv6_icmp_error_rfc4884(const struct sk_buff *skb, 289 struct sock_ee_data_rfc4884 *out) 290 { 291 switch (icmp6_hdr(skb)->icmp6_type) { 292 case ICMPV6_TIME_EXCEED: 293 case ICMPV6_DEST_UNREACH: 294 ip_icmp_error_rfc4884(skb, out, sizeof(struct icmp6hdr), 295 icmp6_hdr(skb)->icmp6_datagram_len * 8); 296 } 297 } 298 299 void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err, 300 __be16 port, u32 info, u8 *payload) 301 { 302 struct ipv6_pinfo *np = inet6_sk(sk); 303 struct icmp6hdr *icmph = icmp6_hdr(skb); 304 struct sock_exterr_skb *serr; 305 306 if (!np->recverr) 307 return; 308 309 skb = skb_clone(skb, GFP_ATOMIC); 310 if (!skb) 311 return; 312 313 skb->protocol = htons(ETH_P_IPV6); 314 315 serr = SKB_EXT_ERR(skb); 316 serr->ee.ee_errno = err; 317 serr->ee.ee_origin = SO_EE_ORIGIN_ICMP6; 318 serr->ee.ee_type = icmph->icmp6_type; 319 serr->ee.ee_code = icmph->icmp6_code; 320 serr->ee.ee_pad = 0; 321 serr->ee.ee_info = info; 322 serr->ee.ee_data = 0; 323 serr->addr_offset = (u8 *)&(((struct ipv6hdr *)(icmph + 1))->daddr) - 324 skb_network_header(skb); 325 serr->port = port; 326 327 __skb_pull(skb, payload - skb->data); 328 329 if (inet6_sk(sk)->recverr_rfc4884) 330 ipv6_icmp_error_rfc4884(skb, &serr->ee.ee_rfc4884); 331 332 skb_reset_transport_header(skb); 333 334 if (sock_queue_err_skb(sk, skb)) 335 kfree_skb(skb); 336 } 337 EXPORT_SYMBOL_GPL(ipv6_icmp_error); 338 339 void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info) 340 { 341 const struct ipv6_pinfo *np = inet6_sk(sk); 342 struct sock_exterr_skb *serr; 343 struct ipv6hdr *iph; 344 struct sk_buff *skb; 345 346 if (!np->recverr) 347 return; 348 349 skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC); 350 if (!skb) 351 return; 352 353 skb->protocol = htons(ETH_P_IPV6); 354 355 skb_put(skb, sizeof(struct ipv6hdr)); 356 skb_reset_network_header(skb); 357 iph = ipv6_hdr(skb); 358 iph->daddr = fl6->daddr; 359 ip6_flow_hdr(iph, 0, 0); 360 361 serr = SKB_EXT_ERR(skb); 362 serr->ee.ee_errno = err; 363 serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL; 364 serr->ee.ee_type = 0; 365 serr->ee.ee_code = 0; 366 serr->ee.ee_pad = 0; 367 serr->ee.ee_info = info; 368 serr->ee.ee_data = 0; 369 serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb); 370 serr->port = fl6->fl6_dport; 371 372 __skb_pull(skb, skb_tail_pointer(skb) - skb->data); 373 skb_reset_transport_header(skb); 374 375 if (sock_queue_err_skb(sk, skb)) 376 kfree_skb(skb); 377 } 378 379 void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu) 380 { 381 struct ipv6_pinfo *np = inet6_sk(sk); 382 struct ipv6hdr *iph; 383 struct sk_buff *skb; 384 struct ip6_mtuinfo *mtu_info; 385 386 if (!np->rxopt.bits.rxpmtu) 387 return; 388 389 skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC); 390 if (!skb) 391 return; 392 393 skb_put(skb, sizeof(struct ipv6hdr)); 394 skb_reset_network_header(skb); 395 iph = ipv6_hdr(skb); 396 iph->daddr = fl6->daddr; 397 398 mtu_info = IP6CBMTU(skb); 399 400 mtu_info->ip6m_mtu = mtu; 401 mtu_info->ip6m_addr.sin6_family = AF_INET6; 402 mtu_info->ip6m_addr.sin6_port = 0; 403 mtu_info->ip6m_addr.sin6_flowinfo = 0; 404 mtu_info->ip6m_addr.sin6_scope_id = fl6->flowi6_oif; 405 mtu_info->ip6m_addr.sin6_addr = ipv6_hdr(skb)->daddr; 406 407 __skb_pull(skb, skb_tail_pointer(skb) - skb->data); 408 skb_reset_transport_header(skb); 409 410 skb = xchg(&np->rxpmtu, skb); 411 kfree_skb(skb); 412 } 413 414 /* For some errors we have valid addr_offset even with zero payload and 415 * zero port. Also, addr_offset should be supported if port is set. 416 */ 417 static inline bool ipv6_datagram_support_addr(struct sock_exterr_skb *serr) 418 { 419 return serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6 || 420 serr->ee.ee_origin == SO_EE_ORIGIN_ICMP || 421 serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL || serr->port; 422 } 423 424 /* IPv6 supports cmsg on all origins aside from SO_EE_ORIGIN_LOCAL. 425 * 426 * At one point, excluding local errors was a quick test to identify icmp/icmp6 427 * errors. This is no longer true, but the test remained, so the v6 stack, 428 * unlike v4, also honors cmsg requests on all wifi and timestamp errors. 429 */ 430 static bool ip6_datagram_support_cmsg(struct sk_buff *skb, 431 struct sock_exterr_skb *serr) 432 { 433 if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP || 434 serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6) 435 return true; 436 437 if (serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL) 438 return false; 439 440 if (!IP6CB(skb)->iif) 441 return false; 442 443 return true; 444 } 445 446 /* 447 * Handle MSG_ERRQUEUE 448 */ 449 int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len) 450 { 451 struct ipv6_pinfo *np = inet6_sk(sk); 452 struct sock_exterr_skb *serr; 453 struct sk_buff *skb; 454 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name); 455 struct { 456 struct sock_extended_err ee; 457 struct sockaddr_in6 offender; 458 } errhdr; 459 int err; 460 int copied; 461 462 err = -EAGAIN; 463 skb = sock_dequeue_err_skb(sk); 464 if (!skb) 465 goto out; 466 467 copied = skb->len; 468 if (copied > len) { 469 msg->msg_flags |= MSG_TRUNC; 470 copied = len; 471 } 472 err = skb_copy_datagram_msg(skb, 0, msg, copied); 473 if (unlikely(err)) { 474 kfree_skb(skb); 475 return err; 476 } 477 sock_recv_timestamp(msg, sk, skb); 478 479 serr = SKB_EXT_ERR(skb); 480 481 if (sin && ipv6_datagram_support_addr(serr)) { 482 const unsigned char *nh = skb_network_header(skb); 483 sin->sin6_family = AF_INET6; 484 sin->sin6_flowinfo = 0; 485 sin->sin6_port = serr->port; 486 if (skb->protocol == htons(ETH_P_IPV6)) { 487 const struct ipv6hdr *ip6h = container_of((struct in6_addr *)(nh + serr->addr_offset), 488 struct ipv6hdr, daddr); 489 sin->sin6_addr = ip6h->daddr; 490 if (np->sndflow) 491 sin->sin6_flowinfo = ip6_flowinfo(ip6h); 492 sin->sin6_scope_id = 493 ipv6_iface_scope_id(&sin->sin6_addr, 494 IP6CB(skb)->iif); 495 } else { 496 ipv6_addr_set_v4mapped(*(__be32 *)(nh + serr->addr_offset), 497 &sin->sin6_addr); 498 sin->sin6_scope_id = 0; 499 } 500 *addr_len = sizeof(*sin); 501 } 502 503 memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err)); 504 sin = &errhdr.offender; 505 memset(sin, 0, sizeof(*sin)); 506 507 if (ip6_datagram_support_cmsg(skb, serr)) { 508 sin->sin6_family = AF_INET6; 509 if (np->rxopt.all) 510 ip6_datagram_recv_common_ctl(sk, msg, skb); 511 if (skb->protocol == htons(ETH_P_IPV6)) { 512 sin->sin6_addr = ipv6_hdr(skb)->saddr; 513 if (np->rxopt.all) 514 ip6_datagram_recv_specific_ctl(sk, msg, skb); 515 sin->sin6_scope_id = 516 ipv6_iface_scope_id(&sin->sin6_addr, 517 IP6CB(skb)->iif); 518 } else { 519 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr, 520 &sin->sin6_addr); 521 if (inet_sk(sk)->cmsg_flags) 522 ip_cmsg_recv(msg, skb); 523 } 524 } 525 526 put_cmsg(msg, SOL_IPV6, IPV6_RECVERR, sizeof(errhdr), &errhdr); 527 528 /* Now we could try to dump offended packet options */ 529 530 msg->msg_flags |= MSG_ERRQUEUE; 531 err = copied; 532 533 consume_skb(skb); 534 out: 535 return err; 536 } 537 EXPORT_SYMBOL_GPL(ipv6_recv_error); 538 539 /* 540 * Handle IPV6_RECVPATHMTU 541 */ 542 int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len, 543 int *addr_len) 544 { 545 struct ipv6_pinfo *np = inet6_sk(sk); 546 struct sk_buff *skb; 547 struct ip6_mtuinfo mtu_info; 548 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name); 549 int err; 550 int copied; 551 552 err = -EAGAIN; 553 skb = xchg(&np->rxpmtu, NULL); 554 if (!skb) 555 goto out; 556 557 copied = skb->len; 558 if (copied > len) { 559 msg->msg_flags |= MSG_TRUNC; 560 copied = len; 561 } 562 err = skb_copy_datagram_msg(skb, 0, msg, copied); 563 if (err) 564 goto out_free_skb; 565 566 sock_recv_timestamp(msg, sk, skb); 567 568 memcpy(&mtu_info, IP6CBMTU(skb), sizeof(mtu_info)); 569 570 if (sin) { 571 sin->sin6_family = AF_INET6; 572 sin->sin6_flowinfo = 0; 573 sin->sin6_port = 0; 574 sin->sin6_scope_id = mtu_info.ip6m_addr.sin6_scope_id; 575 sin->sin6_addr = mtu_info.ip6m_addr.sin6_addr; 576 *addr_len = sizeof(*sin); 577 } 578 579 put_cmsg(msg, SOL_IPV6, IPV6_PATHMTU, sizeof(mtu_info), &mtu_info); 580 581 err = copied; 582 583 out_free_skb: 584 kfree_skb(skb); 585 out: 586 return err; 587 } 588 589 590 void ip6_datagram_recv_common_ctl(struct sock *sk, struct msghdr *msg, 591 struct sk_buff *skb) 592 { 593 struct ipv6_pinfo *np = inet6_sk(sk); 594 bool is_ipv6 = skb->protocol == htons(ETH_P_IPV6); 595 596 if (np->rxopt.bits.rxinfo) { 597 struct in6_pktinfo src_info; 598 599 if (is_ipv6) { 600 src_info.ipi6_ifindex = IP6CB(skb)->iif; 601 src_info.ipi6_addr = ipv6_hdr(skb)->daddr; 602 } else { 603 src_info.ipi6_ifindex = 604 PKTINFO_SKB_CB(skb)->ipi_ifindex; 605 ipv6_addr_set_v4mapped(ip_hdr(skb)->daddr, 606 &src_info.ipi6_addr); 607 } 608 609 if (src_info.ipi6_ifindex >= 0) 610 put_cmsg(msg, SOL_IPV6, IPV6_PKTINFO, 611 sizeof(src_info), &src_info); 612 } 613 } 614 615 void ip6_datagram_recv_specific_ctl(struct sock *sk, struct msghdr *msg, 616 struct sk_buff *skb) 617 { 618 struct ipv6_pinfo *np = inet6_sk(sk); 619 struct inet6_skb_parm *opt = IP6CB(skb); 620 unsigned char *nh = skb_network_header(skb); 621 622 if (np->rxopt.bits.rxhlim) { 623 int hlim = ipv6_hdr(skb)->hop_limit; 624 put_cmsg(msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim); 625 } 626 627 if (np->rxopt.bits.rxtclass) { 628 int tclass = ipv6_get_dsfield(ipv6_hdr(skb)); 629 put_cmsg(msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass); 630 } 631 632 if (np->rxopt.bits.rxflow) { 633 __be32 flowinfo = ip6_flowinfo((struct ipv6hdr *)nh); 634 if (flowinfo) 635 put_cmsg(msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo); 636 } 637 638 /* HbH is allowed only once */ 639 if (np->rxopt.bits.hopopts && (opt->flags & IP6SKB_HOPBYHOP)) { 640 u8 *ptr = nh + sizeof(struct ipv6hdr); 641 put_cmsg(msg, SOL_IPV6, IPV6_HOPOPTS, (ptr[1]+1)<<3, ptr); 642 } 643 644 if (opt->lastopt && 645 (np->rxopt.bits.dstopts || np->rxopt.bits.srcrt)) { 646 /* 647 * Silly enough, but we need to reparse in order to 648 * report extension headers (except for HbH) 649 * in order. 650 * 651 * Also note that IPV6_RECVRTHDRDSTOPTS is NOT 652 * (and WILL NOT be) defined because 653 * IPV6_RECVDSTOPTS is more generic. --yoshfuji 654 */ 655 unsigned int off = sizeof(struct ipv6hdr); 656 u8 nexthdr = ipv6_hdr(skb)->nexthdr; 657 658 while (off <= opt->lastopt) { 659 unsigned int len; 660 u8 *ptr = nh + off; 661 662 switch (nexthdr) { 663 case IPPROTO_DSTOPTS: 664 nexthdr = ptr[0]; 665 len = (ptr[1] + 1) << 3; 666 if (np->rxopt.bits.dstopts) 667 put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, len, ptr); 668 break; 669 case IPPROTO_ROUTING: 670 nexthdr = ptr[0]; 671 len = (ptr[1] + 1) << 3; 672 if (np->rxopt.bits.srcrt) 673 put_cmsg(msg, SOL_IPV6, IPV6_RTHDR, len, ptr); 674 break; 675 case IPPROTO_AH: 676 nexthdr = ptr[0]; 677 len = (ptr[1] + 2) << 2; 678 break; 679 default: 680 nexthdr = ptr[0]; 681 len = (ptr[1] + 1) << 3; 682 break; 683 } 684 685 off += len; 686 } 687 } 688 689 /* socket options in old style */ 690 if (np->rxopt.bits.rxoinfo) { 691 struct in6_pktinfo src_info; 692 693 src_info.ipi6_ifindex = opt->iif; 694 src_info.ipi6_addr = ipv6_hdr(skb)->daddr; 695 put_cmsg(msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info); 696 } 697 if (np->rxopt.bits.rxohlim) { 698 int hlim = ipv6_hdr(skb)->hop_limit; 699 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim); 700 } 701 if (np->rxopt.bits.ohopopts && (opt->flags & IP6SKB_HOPBYHOP)) { 702 u8 *ptr = nh + sizeof(struct ipv6hdr); 703 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPOPTS, (ptr[1]+1)<<3, ptr); 704 } 705 if (np->rxopt.bits.odstopts && opt->dst0) { 706 u8 *ptr = nh + opt->dst0; 707 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr); 708 } 709 if (np->rxopt.bits.osrcrt && opt->srcrt) { 710 struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(nh + opt->srcrt); 711 put_cmsg(msg, SOL_IPV6, IPV6_2292RTHDR, (rthdr->hdrlen+1) << 3, rthdr); 712 } 713 if (np->rxopt.bits.odstopts && opt->dst1) { 714 u8 *ptr = nh + opt->dst1; 715 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr); 716 } 717 if (np->rxopt.bits.rxorigdstaddr) { 718 struct sockaddr_in6 sin6; 719 __be16 _ports[2], *ports; 720 721 ports = skb_header_pointer(skb, skb_transport_offset(skb), 722 sizeof(_ports), &_ports); 723 if (ports) { 724 /* All current transport protocols have the port numbers in the 725 * first four bytes of the transport header and this function is 726 * written with this assumption in mind. 727 */ 728 sin6.sin6_family = AF_INET6; 729 sin6.sin6_addr = ipv6_hdr(skb)->daddr; 730 sin6.sin6_port = ports[1]; 731 sin6.sin6_flowinfo = 0; 732 sin6.sin6_scope_id = 733 ipv6_iface_scope_id(&ipv6_hdr(skb)->daddr, 734 opt->iif); 735 736 put_cmsg(msg, SOL_IPV6, IPV6_ORIGDSTADDR, sizeof(sin6), &sin6); 737 } 738 } 739 if (np->rxopt.bits.recvfragsize && opt->frag_max_size) { 740 int val = opt->frag_max_size; 741 742 put_cmsg(msg, SOL_IPV6, IPV6_RECVFRAGSIZE, sizeof(val), &val); 743 } 744 } 745 746 void ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg, 747 struct sk_buff *skb) 748 { 749 ip6_datagram_recv_common_ctl(sk, msg, skb); 750 ip6_datagram_recv_specific_ctl(sk, msg, skb); 751 } 752 EXPORT_SYMBOL_GPL(ip6_datagram_recv_ctl); 753 754 int ip6_datagram_send_ctl(struct net *net, struct sock *sk, 755 struct msghdr *msg, struct flowi6 *fl6, 756 struct ipcm6_cookie *ipc6) 757 { 758 struct in6_pktinfo *src_info; 759 struct cmsghdr *cmsg; 760 struct ipv6_rt_hdr *rthdr; 761 struct ipv6_opt_hdr *hdr; 762 struct ipv6_txoptions *opt = ipc6->opt; 763 int len; 764 int err = 0; 765 766 for_each_cmsghdr(cmsg, msg) { 767 int addr_type; 768 769 if (!CMSG_OK(msg, cmsg)) { 770 err = -EINVAL; 771 goto exit_f; 772 } 773 774 if (cmsg->cmsg_level == SOL_SOCKET) { 775 err = __sock_cmsg_send(sk, cmsg, &ipc6->sockc); 776 if (err) 777 return err; 778 continue; 779 } 780 781 if (cmsg->cmsg_level != SOL_IPV6) 782 continue; 783 784 switch (cmsg->cmsg_type) { 785 case IPV6_PKTINFO: 786 case IPV6_2292PKTINFO: 787 { 788 struct net_device *dev = NULL; 789 int src_idx; 790 791 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct in6_pktinfo))) { 792 err = -EINVAL; 793 goto exit_f; 794 } 795 796 src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg); 797 src_idx = src_info->ipi6_ifindex; 798 799 if (src_idx) { 800 if (fl6->flowi6_oif && 801 src_idx != fl6->flowi6_oif && 802 (READ_ONCE(sk->sk_bound_dev_if) != fl6->flowi6_oif || 803 !sk_dev_equal_l3scope(sk, src_idx))) 804 return -EINVAL; 805 fl6->flowi6_oif = src_idx; 806 } 807 808 addr_type = __ipv6_addr_type(&src_info->ipi6_addr); 809 810 rcu_read_lock(); 811 if (fl6->flowi6_oif) { 812 dev = dev_get_by_index_rcu(net, fl6->flowi6_oif); 813 if (!dev) { 814 rcu_read_unlock(); 815 return -ENODEV; 816 } 817 } else if (addr_type & IPV6_ADDR_LINKLOCAL) { 818 rcu_read_unlock(); 819 return -EINVAL; 820 } 821 822 if (addr_type != IPV6_ADDR_ANY) { 823 int strict = __ipv6_addr_src_scope(addr_type) <= IPV6_ADDR_SCOPE_LINKLOCAL; 824 if (!ipv6_can_nonlocal_bind(net, inet_sk(sk)) && 825 !ipv6_chk_addr_and_flags(net, &src_info->ipi6_addr, 826 dev, !strict, 0, 827 IFA_F_TENTATIVE) && 828 !ipv6_chk_acast_addr_src(net, dev, 829 &src_info->ipi6_addr)) 830 err = -EINVAL; 831 else 832 fl6->saddr = src_info->ipi6_addr; 833 } 834 835 rcu_read_unlock(); 836 837 if (err) 838 goto exit_f; 839 840 break; 841 } 842 843 case IPV6_FLOWINFO: 844 if (cmsg->cmsg_len < CMSG_LEN(4)) { 845 err = -EINVAL; 846 goto exit_f; 847 } 848 849 if (fl6->flowlabel&IPV6_FLOWINFO_MASK) { 850 if ((fl6->flowlabel^*(__be32 *)CMSG_DATA(cmsg))&~IPV6_FLOWINFO_MASK) { 851 err = -EINVAL; 852 goto exit_f; 853 } 854 } 855 fl6->flowlabel = IPV6_FLOWINFO_MASK & *(__be32 *)CMSG_DATA(cmsg); 856 break; 857 858 case IPV6_2292HOPOPTS: 859 case IPV6_HOPOPTS: 860 if (opt->hopopt || cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) { 861 err = -EINVAL; 862 goto exit_f; 863 } 864 865 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg); 866 len = ((hdr->hdrlen + 1) << 3); 867 if (cmsg->cmsg_len < CMSG_LEN(len)) { 868 err = -EINVAL; 869 goto exit_f; 870 } 871 if (!ns_capable(net->user_ns, CAP_NET_RAW)) { 872 err = -EPERM; 873 goto exit_f; 874 } 875 opt->opt_nflen += len; 876 opt->hopopt = hdr; 877 break; 878 879 case IPV6_2292DSTOPTS: 880 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) { 881 err = -EINVAL; 882 goto exit_f; 883 } 884 885 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg); 886 len = ((hdr->hdrlen + 1) << 3); 887 if (cmsg->cmsg_len < CMSG_LEN(len)) { 888 err = -EINVAL; 889 goto exit_f; 890 } 891 if (!ns_capable(net->user_ns, CAP_NET_RAW)) { 892 err = -EPERM; 893 goto exit_f; 894 } 895 if (opt->dst1opt) { 896 err = -EINVAL; 897 goto exit_f; 898 } 899 opt->opt_flen += len; 900 opt->dst1opt = hdr; 901 break; 902 903 case IPV6_DSTOPTS: 904 case IPV6_RTHDRDSTOPTS: 905 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) { 906 err = -EINVAL; 907 goto exit_f; 908 } 909 910 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg); 911 len = ((hdr->hdrlen + 1) << 3); 912 if (cmsg->cmsg_len < CMSG_LEN(len)) { 913 err = -EINVAL; 914 goto exit_f; 915 } 916 if (!ns_capable(net->user_ns, CAP_NET_RAW)) { 917 err = -EPERM; 918 goto exit_f; 919 } 920 if (cmsg->cmsg_type == IPV6_DSTOPTS) { 921 opt->opt_flen += len; 922 opt->dst1opt = hdr; 923 } else { 924 opt->opt_nflen += len; 925 opt->dst0opt = hdr; 926 } 927 break; 928 929 case IPV6_2292RTHDR: 930 case IPV6_RTHDR: 931 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_rt_hdr))) { 932 err = -EINVAL; 933 goto exit_f; 934 } 935 936 rthdr = (struct ipv6_rt_hdr *)CMSG_DATA(cmsg); 937 938 switch (rthdr->type) { 939 #if IS_ENABLED(CONFIG_IPV6_MIP6) 940 case IPV6_SRCRT_TYPE_2: 941 if (rthdr->hdrlen != 2 || 942 rthdr->segments_left != 1) { 943 err = -EINVAL; 944 goto exit_f; 945 } 946 break; 947 #endif 948 default: 949 err = -EINVAL; 950 goto exit_f; 951 } 952 953 len = ((rthdr->hdrlen + 1) << 3); 954 955 if (cmsg->cmsg_len < CMSG_LEN(len)) { 956 err = -EINVAL; 957 goto exit_f; 958 } 959 960 /* segments left must also match */ 961 if ((rthdr->hdrlen >> 1) != rthdr->segments_left) { 962 err = -EINVAL; 963 goto exit_f; 964 } 965 966 opt->opt_nflen += len; 967 opt->srcrt = rthdr; 968 969 if (cmsg->cmsg_type == IPV6_2292RTHDR && opt->dst1opt) { 970 int dsthdrlen = ((opt->dst1opt->hdrlen+1)<<3); 971 972 opt->opt_nflen += dsthdrlen; 973 opt->dst0opt = opt->dst1opt; 974 opt->dst1opt = NULL; 975 opt->opt_flen -= dsthdrlen; 976 } 977 978 break; 979 980 case IPV6_2292HOPLIMIT: 981 case IPV6_HOPLIMIT: 982 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) { 983 err = -EINVAL; 984 goto exit_f; 985 } 986 987 ipc6->hlimit = *(int *)CMSG_DATA(cmsg); 988 if (ipc6->hlimit < -1 || ipc6->hlimit > 0xff) { 989 err = -EINVAL; 990 goto exit_f; 991 } 992 993 break; 994 995 case IPV6_TCLASS: 996 { 997 int tc; 998 999 err = -EINVAL; 1000 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) 1001 goto exit_f; 1002 1003 tc = *(int *)CMSG_DATA(cmsg); 1004 if (tc < -1 || tc > 0xff) 1005 goto exit_f; 1006 1007 err = 0; 1008 ipc6->tclass = tc; 1009 1010 break; 1011 } 1012 1013 case IPV6_DONTFRAG: 1014 { 1015 int df; 1016 1017 err = -EINVAL; 1018 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) 1019 goto exit_f; 1020 1021 df = *(int *)CMSG_DATA(cmsg); 1022 if (df < 0 || df > 1) 1023 goto exit_f; 1024 1025 err = 0; 1026 ipc6->dontfrag = df; 1027 1028 break; 1029 } 1030 default: 1031 net_dbg_ratelimited("invalid cmsg type: %d\n", 1032 cmsg->cmsg_type); 1033 err = -EINVAL; 1034 goto exit_f; 1035 } 1036 } 1037 1038 exit_f: 1039 return err; 1040 } 1041 EXPORT_SYMBOL_GPL(ip6_datagram_send_ctl); 1042 1043 void __ip6_dgram_sock_seq_show(struct seq_file *seq, struct sock *sp, 1044 __u16 srcp, __u16 destp, int rqueue, int bucket) 1045 { 1046 const struct in6_addr *dest, *src; 1047 1048 dest = &sp->sk_v6_daddr; 1049 src = &sp->sk_v6_rcv_saddr; 1050 seq_printf(seq, 1051 "%5d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " 1052 "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %u\n", 1053 bucket, 1054 src->s6_addr32[0], src->s6_addr32[1], 1055 src->s6_addr32[2], src->s6_addr32[3], srcp, 1056 dest->s6_addr32[0], dest->s6_addr32[1], 1057 dest->s6_addr32[2], dest->s6_addr32[3], destp, 1058 sp->sk_state, 1059 sk_wmem_alloc_get(sp), 1060 rqueue, 1061 0, 0L, 0, 1062 from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)), 1063 0, 1064 sock_i_ino(sp), 1065 refcount_read(&sp->sk_refcnt), sp, 1066 atomic_read(&sp->sk_drops)); 1067 } 1068