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 23 #include <net/ipv6.h> 24 #include <net/ndisc.h> 25 #include <net/addrconf.h> 26 #include <net/transp_v6.h> 27 #include <net/ip6_route.h> 28 #include <net/tcp_states.h> 29 #include <net/dsfield.h> 30 #include <net/sock_reuseport.h> 31 32 #include <linux/errqueue.h> 33 #include <linux/uaccess.h> 34 35 static bool ipv6_mapped_addr_any(const struct in6_addr *a) 36 { 37 return ipv6_addr_v4mapped(a) && (a->s6_addr32[3] == 0); 38 } 39 40 static void ip6_datagram_flow_key_init(struct flowi6 *fl6, struct sock *sk) 41 { 42 struct inet_sock *inet = inet_sk(sk); 43 struct ipv6_pinfo *np = inet6_sk(sk); 44 45 memset(fl6, 0, sizeof(*fl6)); 46 fl6->flowi6_proto = sk->sk_protocol; 47 fl6->daddr = sk->sk_v6_daddr; 48 fl6->saddr = np->saddr; 49 fl6->flowi6_oif = sk->sk_bound_dev_if; 50 fl6->flowi6_mark = sk->sk_mark; 51 fl6->fl6_dport = inet->inet_dport; 52 fl6->fl6_sport = inet->inet_sport; 53 fl6->flowlabel = np->flow_label; 54 fl6->flowi6_uid = sk->sk_uid; 55 56 if (!fl6->flowi6_oif) 57 fl6->flowi6_oif = np->sticky_pktinfo.ipi6_ifindex; 58 59 if (!fl6->flowi6_oif && ipv6_addr_is_multicast(&fl6->daddr)) 60 fl6->flowi6_oif = np->mcast_oif; 61 62 security_sk_classify_flow(sk, flowi6_to_flowi(fl6)); 63 } 64 65 int ip6_datagram_dst_update(struct sock *sk, bool fix_sk_saddr) 66 { 67 struct ip6_flowlabel *flowlabel = NULL; 68 struct in6_addr *final_p, final; 69 struct ipv6_txoptions *opt; 70 struct dst_entry *dst; 71 struct inet_sock *inet = inet_sk(sk); 72 struct ipv6_pinfo *np = inet6_sk(sk); 73 struct flowi6 fl6; 74 int err = 0; 75 76 if (np->sndflow && (np->flow_label & IPV6_FLOWLABEL_MASK)) { 77 flowlabel = fl6_sock_lookup(sk, np->flow_label); 78 if (IS_ERR(flowlabel)) 79 return -EINVAL; 80 } 81 ip6_datagram_flow_key_init(&fl6, sk); 82 83 rcu_read_lock(); 84 opt = flowlabel ? flowlabel->opt : rcu_dereference(np->opt); 85 final_p = fl6_update_dst(&fl6, opt, &final); 86 rcu_read_unlock(); 87 88 dst = ip6_dst_lookup_flow(sk, &fl6, final_p); 89 if (IS_ERR(dst)) { 90 err = PTR_ERR(dst); 91 goto out; 92 } 93 94 if (fix_sk_saddr) { 95 if (ipv6_addr_any(&np->saddr)) 96 np->saddr = fl6.saddr; 97 98 if (ipv6_addr_any(&sk->sk_v6_rcv_saddr)) { 99 sk->sk_v6_rcv_saddr = fl6.saddr; 100 inet->inet_rcv_saddr = LOOPBACK4_IPV6; 101 if (sk->sk_prot->rehash) 102 sk->sk_prot->rehash(sk); 103 } 104 } 105 106 ip6_sk_dst_store_flow(sk, dst, &fl6); 107 108 out: 109 fl6_sock_release(flowlabel); 110 return err; 111 } 112 113 void ip6_datagram_release_cb(struct sock *sk) 114 { 115 struct dst_entry *dst; 116 117 if (ipv6_addr_v4mapped(&sk->sk_v6_daddr)) 118 return; 119 120 rcu_read_lock(); 121 dst = __sk_dst_get(sk); 122 if (!dst || !dst->obsolete || 123 dst->ops->check(dst, inet6_sk(sk)->dst_cookie)) { 124 rcu_read_unlock(); 125 return; 126 } 127 rcu_read_unlock(); 128 129 ip6_datagram_dst_update(sk, false); 130 } 131 EXPORT_SYMBOL_GPL(ip6_datagram_release_cb); 132 133 int __ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, 134 int addr_len) 135 { 136 struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr; 137 struct inet_sock *inet = inet_sk(sk); 138 struct ipv6_pinfo *np = inet6_sk(sk); 139 struct in6_addr *daddr, old_daddr; 140 __be32 fl6_flowlabel = 0; 141 __be32 old_fl6_flowlabel; 142 __be16 old_dport; 143 int addr_type; 144 int err; 145 146 if (usin->sin6_family == AF_INET) { 147 if (__ipv6_only_sock(sk)) 148 return -EAFNOSUPPORT; 149 err = __ip4_datagram_connect(sk, uaddr, addr_len); 150 goto ipv4_connected; 151 } 152 153 if (addr_len < SIN6_LEN_RFC2133) 154 return -EINVAL; 155 156 if (usin->sin6_family != AF_INET6) 157 return -EAFNOSUPPORT; 158 159 if (np->sndflow) 160 fl6_flowlabel = usin->sin6_flowinfo & IPV6_FLOWINFO_MASK; 161 162 if (ipv6_addr_any(&usin->sin6_addr)) { 163 /* 164 * connect to self 165 */ 166 if (ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr)) 167 ipv6_addr_set_v4mapped(htonl(INADDR_LOOPBACK), 168 &usin->sin6_addr); 169 else 170 usin->sin6_addr = in6addr_loopback; 171 } 172 173 addr_type = ipv6_addr_type(&usin->sin6_addr); 174 175 daddr = &usin->sin6_addr; 176 177 if (addr_type & IPV6_ADDR_MAPPED) { 178 struct sockaddr_in sin; 179 180 if (__ipv6_only_sock(sk)) { 181 err = -ENETUNREACH; 182 goto out; 183 } 184 sin.sin_family = AF_INET; 185 sin.sin_addr.s_addr = daddr->s6_addr32[3]; 186 sin.sin_port = usin->sin6_port; 187 188 err = __ip4_datagram_connect(sk, 189 (struct sockaddr *) &sin, 190 sizeof(sin)); 191 192 ipv4_connected: 193 if (err) 194 goto out; 195 196 ipv6_addr_set_v4mapped(inet->inet_daddr, &sk->sk_v6_daddr); 197 198 if (ipv6_addr_any(&np->saddr) || 199 ipv6_mapped_addr_any(&np->saddr)) 200 ipv6_addr_set_v4mapped(inet->inet_saddr, &np->saddr); 201 202 if (ipv6_addr_any(&sk->sk_v6_rcv_saddr) || 203 ipv6_mapped_addr_any(&sk->sk_v6_rcv_saddr)) { 204 ipv6_addr_set_v4mapped(inet->inet_rcv_saddr, 205 &sk->sk_v6_rcv_saddr); 206 if (sk->sk_prot->rehash) 207 sk->sk_prot->rehash(sk); 208 } 209 210 goto out; 211 } 212 213 if (__ipv6_addr_needs_scope_id(addr_type)) { 214 if (addr_len >= sizeof(struct sockaddr_in6) && 215 usin->sin6_scope_id) { 216 if (!sk_dev_equal_l3scope(sk, usin->sin6_scope_id)) { 217 err = -EINVAL; 218 goto out; 219 } 220 sk->sk_bound_dev_if = usin->sin6_scope_id; 221 } 222 223 if (!sk->sk_bound_dev_if && (addr_type & IPV6_ADDR_MULTICAST)) 224 sk->sk_bound_dev_if = np->mcast_oif; 225 226 /* Connect to link-local address requires an interface */ 227 if (!sk->sk_bound_dev_if) { 228 err = -EINVAL; 229 goto out; 230 } 231 } 232 233 /* save the current peer information before updating it */ 234 old_daddr = sk->sk_v6_daddr; 235 old_fl6_flowlabel = np->flow_label; 236 old_dport = inet->inet_dport; 237 238 sk->sk_v6_daddr = *daddr; 239 np->flow_label = fl6_flowlabel; 240 inet->inet_dport = usin->sin6_port; 241 242 /* 243 * Check for a route to destination an obtain the 244 * destination cache for it. 245 */ 246 247 err = ip6_datagram_dst_update(sk, true); 248 if (err) { 249 /* Restore the socket peer info, to keep it consistent with 250 * the old socket state 251 */ 252 sk->sk_v6_daddr = old_daddr; 253 np->flow_label = old_fl6_flowlabel; 254 inet->inet_dport = old_dport; 255 goto out; 256 } 257 258 reuseport_has_conns(sk, true); 259 sk->sk_state = TCP_ESTABLISHED; 260 sk_set_txhash(sk); 261 out: 262 return err; 263 } 264 EXPORT_SYMBOL_GPL(__ip6_datagram_connect); 265 266 int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) 267 { 268 int res; 269 270 lock_sock(sk); 271 res = __ip6_datagram_connect(sk, uaddr, addr_len); 272 release_sock(sk); 273 return res; 274 } 275 EXPORT_SYMBOL_GPL(ip6_datagram_connect); 276 277 int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *uaddr, 278 int addr_len) 279 { 280 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, uaddr); 281 if (sin6->sin6_family != AF_INET6) 282 return -EAFNOSUPPORT; 283 return ip6_datagram_connect(sk, uaddr, addr_len); 284 } 285 EXPORT_SYMBOL_GPL(ip6_datagram_connect_v6_only); 286 287 void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err, 288 __be16 port, u32 info, u8 *payload) 289 { 290 struct ipv6_pinfo *np = inet6_sk(sk); 291 struct icmp6hdr *icmph = icmp6_hdr(skb); 292 struct sock_exterr_skb *serr; 293 294 if (!np->recverr) 295 return; 296 297 skb = skb_clone(skb, GFP_ATOMIC); 298 if (!skb) 299 return; 300 301 skb->protocol = htons(ETH_P_IPV6); 302 303 serr = SKB_EXT_ERR(skb); 304 serr->ee.ee_errno = err; 305 serr->ee.ee_origin = SO_EE_ORIGIN_ICMP6; 306 serr->ee.ee_type = icmph->icmp6_type; 307 serr->ee.ee_code = icmph->icmp6_code; 308 serr->ee.ee_pad = 0; 309 serr->ee.ee_info = info; 310 serr->ee.ee_data = 0; 311 serr->addr_offset = (u8 *)&(((struct ipv6hdr *)(icmph + 1))->daddr) - 312 skb_network_header(skb); 313 serr->port = port; 314 315 __skb_pull(skb, payload - skb->data); 316 skb_reset_transport_header(skb); 317 318 if (sock_queue_err_skb(sk, skb)) 319 kfree_skb(skb); 320 } 321 322 void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info) 323 { 324 const struct ipv6_pinfo *np = inet6_sk(sk); 325 struct sock_exterr_skb *serr; 326 struct ipv6hdr *iph; 327 struct sk_buff *skb; 328 329 if (!np->recverr) 330 return; 331 332 skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC); 333 if (!skb) 334 return; 335 336 skb->protocol = htons(ETH_P_IPV6); 337 338 skb_put(skb, sizeof(struct ipv6hdr)); 339 skb_reset_network_header(skb); 340 iph = ipv6_hdr(skb); 341 iph->daddr = fl6->daddr; 342 ip6_flow_hdr(iph, 0, 0); 343 344 serr = SKB_EXT_ERR(skb); 345 serr->ee.ee_errno = err; 346 serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL; 347 serr->ee.ee_type = 0; 348 serr->ee.ee_code = 0; 349 serr->ee.ee_pad = 0; 350 serr->ee.ee_info = info; 351 serr->ee.ee_data = 0; 352 serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb); 353 serr->port = fl6->fl6_dport; 354 355 __skb_pull(skb, skb_tail_pointer(skb) - skb->data); 356 skb_reset_transport_header(skb); 357 358 if (sock_queue_err_skb(sk, skb)) 359 kfree_skb(skb); 360 } 361 362 void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu) 363 { 364 struct ipv6_pinfo *np = inet6_sk(sk); 365 struct ipv6hdr *iph; 366 struct sk_buff *skb; 367 struct ip6_mtuinfo *mtu_info; 368 369 if (!np->rxopt.bits.rxpmtu) 370 return; 371 372 skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC); 373 if (!skb) 374 return; 375 376 skb_put(skb, sizeof(struct ipv6hdr)); 377 skb_reset_network_header(skb); 378 iph = ipv6_hdr(skb); 379 iph->daddr = fl6->daddr; 380 381 mtu_info = IP6CBMTU(skb); 382 383 mtu_info->ip6m_mtu = mtu; 384 mtu_info->ip6m_addr.sin6_family = AF_INET6; 385 mtu_info->ip6m_addr.sin6_port = 0; 386 mtu_info->ip6m_addr.sin6_flowinfo = 0; 387 mtu_info->ip6m_addr.sin6_scope_id = fl6->flowi6_oif; 388 mtu_info->ip6m_addr.sin6_addr = ipv6_hdr(skb)->daddr; 389 390 __skb_pull(skb, skb_tail_pointer(skb) - skb->data); 391 skb_reset_transport_header(skb); 392 393 skb = xchg(&np->rxpmtu, skb); 394 kfree_skb(skb); 395 } 396 397 /* For some errors we have valid addr_offset even with zero payload and 398 * zero port. Also, addr_offset should be supported if port is set. 399 */ 400 static inline bool ipv6_datagram_support_addr(struct sock_exterr_skb *serr) 401 { 402 return serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6 || 403 serr->ee.ee_origin == SO_EE_ORIGIN_ICMP || 404 serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL || serr->port; 405 } 406 407 /* IPv6 supports cmsg on all origins aside from SO_EE_ORIGIN_LOCAL. 408 * 409 * At one point, excluding local errors was a quick test to identify icmp/icmp6 410 * errors. This is no longer true, but the test remained, so the v6 stack, 411 * unlike v4, also honors cmsg requests on all wifi and timestamp errors. 412 */ 413 static bool ip6_datagram_support_cmsg(struct sk_buff *skb, 414 struct sock_exterr_skb *serr) 415 { 416 if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP || 417 serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6) 418 return true; 419 420 if (serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL) 421 return false; 422 423 if (!IP6CB(skb)->iif) 424 return false; 425 426 return true; 427 } 428 429 /* 430 * Handle MSG_ERRQUEUE 431 */ 432 int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len) 433 { 434 struct ipv6_pinfo *np = inet6_sk(sk); 435 struct sock_exterr_skb *serr; 436 struct sk_buff *skb; 437 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name); 438 struct { 439 struct sock_extended_err ee; 440 struct sockaddr_in6 offender; 441 } errhdr; 442 int err; 443 int copied; 444 445 err = -EAGAIN; 446 skb = sock_dequeue_err_skb(sk); 447 if (!skb) 448 goto out; 449 450 copied = skb->len; 451 if (copied > len) { 452 msg->msg_flags |= MSG_TRUNC; 453 copied = len; 454 } 455 err = skb_copy_datagram_msg(skb, 0, msg, copied); 456 if (unlikely(err)) { 457 kfree_skb(skb); 458 return err; 459 } 460 sock_recv_timestamp(msg, sk, skb); 461 462 serr = SKB_EXT_ERR(skb); 463 464 if (sin && ipv6_datagram_support_addr(serr)) { 465 const unsigned char *nh = skb_network_header(skb); 466 sin->sin6_family = AF_INET6; 467 sin->sin6_flowinfo = 0; 468 sin->sin6_port = serr->port; 469 if (skb->protocol == htons(ETH_P_IPV6)) { 470 const struct ipv6hdr *ip6h = container_of((struct in6_addr *)(nh + serr->addr_offset), 471 struct ipv6hdr, daddr); 472 sin->sin6_addr = ip6h->daddr; 473 if (np->sndflow) 474 sin->sin6_flowinfo = ip6_flowinfo(ip6h); 475 sin->sin6_scope_id = 476 ipv6_iface_scope_id(&sin->sin6_addr, 477 IP6CB(skb)->iif); 478 } else { 479 ipv6_addr_set_v4mapped(*(__be32 *)(nh + serr->addr_offset), 480 &sin->sin6_addr); 481 sin->sin6_scope_id = 0; 482 } 483 *addr_len = sizeof(*sin); 484 } 485 486 memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err)); 487 sin = &errhdr.offender; 488 memset(sin, 0, sizeof(*sin)); 489 490 if (ip6_datagram_support_cmsg(skb, serr)) { 491 sin->sin6_family = AF_INET6; 492 if (np->rxopt.all) 493 ip6_datagram_recv_common_ctl(sk, msg, skb); 494 if (skb->protocol == htons(ETH_P_IPV6)) { 495 sin->sin6_addr = ipv6_hdr(skb)->saddr; 496 if (np->rxopt.all) 497 ip6_datagram_recv_specific_ctl(sk, msg, skb); 498 sin->sin6_scope_id = 499 ipv6_iface_scope_id(&sin->sin6_addr, 500 IP6CB(skb)->iif); 501 } else { 502 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr, 503 &sin->sin6_addr); 504 if (inet_sk(sk)->cmsg_flags) 505 ip_cmsg_recv(msg, skb); 506 } 507 } 508 509 put_cmsg(msg, SOL_IPV6, IPV6_RECVERR, sizeof(errhdr), &errhdr); 510 511 /* Now we could try to dump offended packet options */ 512 513 msg->msg_flags |= MSG_ERRQUEUE; 514 err = copied; 515 516 consume_skb(skb); 517 out: 518 return err; 519 } 520 EXPORT_SYMBOL_GPL(ipv6_recv_error); 521 522 /* 523 * Handle IPV6_RECVPATHMTU 524 */ 525 int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len, 526 int *addr_len) 527 { 528 struct ipv6_pinfo *np = inet6_sk(sk); 529 struct sk_buff *skb; 530 struct ip6_mtuinfo mtu_info; 531 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name); 532 int err; 533 int copied; 534 535 err = -EAGAIN; 536 skb = xchg(&np->rxpmtu, NULL); 537 if (!skb) 538 goto out; 539 540 copied = skb->len; 541 if (copied > len) { 542 msg->msg_flags |= MSG_TRUNC; 543 copied = len; 544 } 545 err = skb_copy_datagram_msg(skb, 0, msg, copied); 546 if (err) 547 goto out_free_skb; 548 549 sock_recv_timestamp(msg, sk, skb); 550 551 memcpy(&mtu_info, IP6CBMTU(skb), sizeof(mtu_info)); 552 553 if (sin) { 554 sin->sin6_family = AF_INET6; 555 sin->sin6_flowinfo = 0; 556 sin->sin6_port = 0; 557 sin->sin6_scope_id = mtu_info.ip6m_addr.sin6_scope_id; 558 sin->sin6_addr = mtu_info.ip6m_addr.sin6_addr; 559 *addr_len = sizeof(*sin); 560 } 561 562 put_cmsg(msg, SOL_IPV6, IPV6_PATHMTU, sizeof(mtu_info), &mtu_info); 563 564 err = copied; 565 566 out_free_skb: 567 kfree_skb(skb); 568 out: 569 return err; 570 } 571 572 573 void ip6_datagram_recv_common_ctl(struct sock *sk, struct msghdr *msg, 574 struct sk_buff *skb) 575 { 576 struct ipv6_pinfo *np = inet6_sk(sk); 577 bool is_ipv6 = skb->protocol == htons(ETH_P_IPV6); 578 579 if (np->rxopt.bits.rxinfo) { 580 struct in6_pktinfo src_info; 581 582 if (is_ipv6) { 583 src_info.ipi6_ifindex = IP6CB(skb)->iif; 584 src_info.ipi6_addr = ipv6_hdr(skb)->daddr; 585 } else { 586 src_info.ipi6_ifindex = 587 PKTINFO_SKB_CB(skb)->ipi_ifindex; 588 ipv6_addr_set_v4mapped(ip_hdr(skb)->daddr, 589 &src_info.ipi6_addr); 590 } 591 592 if (src_info.ipi6_ifindex >= 0) 593 put_cmsg(msg, SOL_IPV6, IPV6_PKTINFO, 594 sizeof(src_info), &src_info); 595 } 596 } 597 598 void ip6_datagram_recv_specific_ctl(struct sock *sk, struct msghdr *msg, 599 struct sk_buff *skb) 600 { 601 struct ipv6_pinfo *np = inet6_sk(sk); 602 struct inet6_skb_parm *opt = IP6CB(skb); 603 unsigned char *nh = skb_network_header(skb); 604 605 if (np->rxopt.bits.rxhlim) { 606 int hlim = ipv6_hdr(skb)->hop_limit; 607 put_cmsg(msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim); 608 } 609 610 if (np->rxopt.bits.rxtclass) { 611 int tclass = ipv6_get_dsfield(ipv6_hdr(skb)); 612 put_cmsg(msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass); 613 } 614 615 if (np->rxopt.bits.rxflow) { 616 __be32 flowinfo = ip6_flowinfo((struct ipv6hdr *)nh); 617 if (flowinfo) 618 put_cmsg(msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo); 619 } 620 621 /* HbH is allowed only once */ 622 if (np->rxopt.bits.hopopts && (opt->flags & IP6SKB_HOPBYHOP)) { 623 u8 *ptr = nh + sizeof(struct ipv6hdr); 624 put_cmsg(msg, SOL_IPV6, IPV6_HOPOPTS, (ptr[1]+1)<<3, ptr); 625 } 626 627 if (opt->lastopt && 628 (np->rxopt.bits.dstopts || np->rxopt.bits.srcrt)) { 629 /* 630 * Silly enough, but we need to reparse in order to 631 * report extension headers (except for HbH) 632 * in order. 633 * 634 * Also note that IPV6_RECVRTHDRDSTOPTS is NOT 635 * (and WILL NOT be) defined because 636 * IPV6_RECVDSTOPTS is more generic. --yoshfuji 637 */ 638 unsigned int off = sizeof(struct ipv6hdr); 639 u8 nexthdr = ipv6_hdr(skb)->nexthdr; 640 641 while (off <= opt->lastopt) { 642 unsigned int len; 643 u8 *ptr = nh + off; 644 645 switch (nexthdr) { 646 case IPPROTO_DSTOPTS: 647 nexthdr = ptr[0]; 648 len = (ptr[1] + 1) << 3; 649 if (np->rxopt.bits.dstopts) 650 put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, len, ptr); 651 break; 652 case IPPROTO_ROUTING: 653 nexthdr = ptr[0]; 654 len = (ptr[1] + 1) << 3; 655 if (np->rxopt.bits.srcrt) 656 put_cmsg(msg, SOL_IPV6, IPV6_RTHDR, len, ptr); 657 break; 658 case IPPROTO_AH: 659 nexthdr = ptr[0]; 660 len = (ptr[1] + 2) << 2; 661 break; 662 default: 663 nexthdr = ptr[0]; 664 len = (ptr[1] + 1) << 3; 665 break; 666 } 667 668 off += len; 669 } 670 } 671 672 /* socket options in old style */ 673 if (np->rxopt.bits.rxoinfo) { 674 struct in6_pktinfo src_info; 675 676 src_info.ipi6_ifindex = opt->iif; 677 src_info.ipi6_addr = ipv6_hdr(skb)->daddr; 678 put_cmsg(msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info); 679 } 680 if (np->rxopt.bits.rxohlim) { 681 int hlim = ipv6_hdr(skb)->hop_limit; 682 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim); 683 } 684 if (np->rxopt.bits.ohopopts && (opt->flags & IP6SKB_HOPBYHOP)) { 685 u8 *ptr = nh + sizeof(struct ipv6hdr); 686 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPOPTS, (ptr[1]+1)<<3, ptr); 687 } 688 if (np->rxopt.bits.odstopts && opt->dst0) { 689 u8 *ptr = nh + opt->dst0; 690 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr); 691 } 692 if (np->rxopt.bits.osrcrt && opt->srcrt) { 693 struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(nh + opt->srcrt); 694 put_cmsg(msg, SOL_IPV6, IPV6_2292RTHDR, (rthdr->hdrlen+1) << 3, rthdr); 695 } 696 if (np->rxopt.bits.odstopts && opt->dst1) { 697 u8 *ptr = nh + opt->dst1; 698 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr); 699 } 700 if (np->rxopt.bits.rxorigdstaddr) { 701 struct sockaddr_in6 sin6; 702 __be16 _ports[2], *ports; 703 704 ports = skb_header_pointer(skb, skb_transport_offset(skb), 705 sizeof(_ports), &_ports); 706 if (ports) { 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 sin6.sin6_family = AF_INET6; 712 sin6.sin6_addr = ipv6_hdr(skb)->daddr; 713 sin6.sin6_port = ports[1]; 714 sin6.sin6_flowinfo = 0; 715 sin6.sin6_scope_id = 716 ipv6_iface_scope_id(&ipv6_hdr(skb)->daddr, 717 opt->iif); 718 719 put_cmsg(msg, SOL_IPV6, IPV6_ORIGDSTADDR, sizeof(sin6), &sin6); 720 } 721 } 722 if (np->rxopt.bits.recvfragsize && opt->frag_max_size) { 723 int val = opt->frag_max_size; 724 725 put_cmsg(msg, SOL_IPV6, IPV6_RECVFRAGSIZE, sizeof(val), &val); 726 } 727 } 728 729 void ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg, 730 struct sk_buff *skb) 731 { 732 ip6_datagram_recv_common_ctl(sk, msg, skb); 733 ip6_datagram_recv_specific_ctl(sk, msg, skb); 734 } 735 EXPORT_SYMBOL_GPL(ip6_datagram_recv_ctl); 736 737 int ip6_datagram_send_ctl(struct net *net, struct sock *sk, 738 struct msghdr *msg, struct flowi6 *fl6, 739 struct ipcm6_cookie *ipc6) 740 { 741 struct in6_pktinfo *src_info; 742 struct cmsghdr *cmsg; 743 struct ipv6_rt_hdr *rthdr; 744 struct ipv6_opt_hdr *hdr; 745 struct ipv6_txoptions *opt = ipc6->opt; 746 int len; 747 int err = 0; 748 749 for_each_cmsghdr(cmsg, msg) { 750 int addr_type; 751 752 if (!CMSG_OK(msg, cmsg)) { 753 err = -EINVAL; 754 goto exit_f; 755 } 756 757 if (cmsg->cmsg_level == SOL_SOCKET) { 758 err = __sock_cmsg_send(sk, msg, cmsg, &ipc6->sockc); 759 if (err) 760 return err; 761 continue; 762 } 763 764 if (cmsg->cmsg_level != SOL_IPV6) 765 continue; 766 767 switch (cmsg->cmsg_type) { 768 case IPV6_PKTINFO: 769 case IPV6_2292PKTINFO: 770 { 771 struct net_device *dev = NULL; 772 int src_idx; 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 src_idx = src_info->ipi6_ifindex; 781 782 if (src_idx) { 783 if (fl6->flowi6_oif && 784 src_idx != fl6->flowi6_oif && 785 (sk->sk_bound_dev_if != fl6->flowi6_oif || 786 !sk_dev_equal_l3scope(sk, src_idx))) 787 return -EINVAL; 788 fl6->flowi6_oif = src_idx; 789 } 790 791 addr_type = __ipv6_addr_type(&src_info->ipi6_addr); 792 793 rcu_read_lock(); 794 if (fl6->flowi6_oif) { 795 dev = dev_get_by_index_rcu(net, fl6->flowi6_oif); 796 if (!dev) { 797 rcu_read_unlock(); 798 return -ENODEV; 799 } 800 } else if (addr_type & IPV6_ADDR_LINKLOCAL) { 801 rcu_read_unlock(); 802 return -EINVAL; 803 } 804 805 if (addr_type != IPV6_ADDR_ANY) { 806 int strict = __ipv6_addr_src_scope(addr_type) <= IPV6_ADDR_SCOPE_LINKLOCAL; 807 if (!ipv6_can_nonlocal_bind(net, inet_sk(sk)) && 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 %u\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