1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * RAW sockets for IPv6 4 * Linux INET6 implementation 5 * 6 * Authors: 7 * Pedro Roque <roque@di.fc.ul.pt> 8 * 9 * Adapted from linux/net/ipv4/raw.c 10 * 11 * Fixes: 12 * Hideaki YOSHIFUJI : sin6_scope_id support 13 * YOSHIFUJI,H.@USAGI : raw checksum (RFC2292(bis) compliance) 14 * Kazunori MIYAZAWA @USAGI: change process style to use ip6_append_data 15 */ 16 17 #include <linux/errno.h> 18 #include <linux/types.h> 19 #include <linux/socket.h> 20 #include <linux/slab.h> 21 #include <linux/sockios.h> 22 #include <linux/net.h> 23 #include <linux/in6.h> 24 #include <linux/netdevice.h> 25 #include <linux/if_arp.h> 26 #include <linux/icmpv6.h> 27 #include <linux/netfilter.h> 28 #include <linux/netfilter_ipv6.h> 29 #include <linux/skbuff.h> 30 #include <linux/compat.h> 31 #include <linux/uaccess.h> 32 #include <asm/ioctls.h> 33 34 #include <net/net_namespace.h> 35 #include <net/ip.h> 36 #include <net/sock.h> 37 #include <net/snmp.h> 38 39 #include <net/ipv6.h> 40 #include <net/ndisc.h> 41 #include <net/protocol.h> 42 #include <net/ip6_route.h> 43 #include <net/ip6_checksum.h> 44 #include <net/addrconf.h> 45 #include <net/transp_v6.h> 46 #include <net/udp.h> 47 #include <net/inet_common.h> 48 #include <net/tcp_states.h> 49 #if IS_ENABLED(CONFIG_IPV6_MIP6) 50 #include <net/mip6.h> 51 #endif 52 #include <linux/mroute6.h> 53 54 #include <net/raw.h> 55 #include <net/rawv6.h> 56 #include <net/xfrm.h> 57 58 #include <linux/proc_fs.h> 59 #include <linux/seq_file.h> 60 #include <linux/export.h> 61 62 #define ICMPV6_HDRLEN 4 /* ICMPv6 header, RFC 4443 Section 2.1 */ 63 64 struct raw_hashinfo raw_v6_hashinfo; 65 EXPORT_SYMBOL_GPL(raw_v6_hashinfo); 66 67 bool raw_v6_match(struct net *net, const struct sock *sk, unsigned short num, 68 const struct in6_addr *loc_addr, 69 const struct in6_addr *rmt_addr, int dif, int sdif) 70 { 71 if (inet_sk(sk)->inet_num != num || 72 !net_eq(sock_net(sk), net) || 73 (!ipv6_addr_any(&sk->sk_v6_daddr) && 74 !ipv6_addr_equal(&sk->sk_v6_daddr, rmt_addr)) || 75 !raw_sk_bound_dev_eq(net, sk->sk_bound_dev_if, 76 dif, sdif)) 77 return false; 78 79 if (ipv6_addr_any(&sk->sk_v6_rcv_saddr) || 80 ipv6_addr_equal(&sk->sk_v6_rcv_saddr, loc_addr) || 81 (ipv6_addr_is_multicast(loc_addr) && 82 inet6_mc_check(sk, loc_addr, rmt_addr))) 83 return true; 84 85 return false; 86 } 87 EXPORT_SYMBOL_GPL(raw_v6_match); 88 89 /* 90 * 0 - deliver 91 * 1 - block 92 */ 93 static int icmpv6_filter(const struct sock *sk, const struct sk_buff *skb) 94 { 95 struct icmp6hdr _hdr; 96 const struct icmp6hdr *hdr; 97 98 /* We require only the four bytes of the ICMPv6 header, not any 99 * additional bytes of message body in "struct icmp6hdr". 100 */ 101 hdr = skb_header_pointer(skb, skb_transport_offset(skb), 102 ICMPV6_HDRLEN, &_hdr); 103 if (hdr) { 104 const __u32 *data = &raw6_sk(sk)->filter.data[0]; 105 unsigned int type = hdr->icmp6_type; 106 107 return (data[type >> 5] & (1U << (type & 31))) != 0; 108 } 109 return 1; 110 } 111 112 #if IS_ENABLED(CONFIG_IPV6_MIP6) 113 typedef int mh_filter_t(struct sock *sock, struct sk_buff *skb); 114 115 static mh_filter_t __rcu *mh_filter __read_mostly; 116 117 int rawv6_mh_filter_register(mh_filter_t filter) 118 { 119 rcu_assign_pointer(mh_filter, filter); 120 return 0; 121 } 122 EXPORT_SYMBOL(rawv6_mh_filter_register); 123 124 int rawv6_mh_filter_unregister(mh_filter_t filter) 125 { 126 RCU_INIT_POINTER(mh_filter, NULL); 127 synchronize_rcu(); 128 return 0; 129 } 130 EXPORT_SYMBOL(rawv6_mh_filter_unregister); 131 132 #endif 133 134 /* 135 * demultiplex raw sockets. 136 * (should consider queueing the skb in the sock receive_queue 137 * without calling rawv6.c) 138 * 139 * Caller owns SKB so we must make clones. 140 */ 141 static bool ipv6_raw_deliver(struct sk_buff *skb, int nexthdr) 142 { 143 struct net *net = dev_net(skb->dev); 144 const struct in6_addr *saddr; 145 const struct in6_addr *daddr; 146 struct hlist_head *hlist; 147 struct sock *sk; 148 bool delivered = false; 149 __u8 hash; 150 151 saddr = &ipv6_hdr(skb)->saddr; 152 daddr = saddr + 1; 153 154 hash = raw_hashfunc(net, nexthdr); 155 hlist = &raw_v6_hashinfo.ht[hash]; 156 rcu_read_lock(); 157 sk_for_each_rcu(sk, hlist) { 158 int filtered; 159 160 if (!raw_v6_match(net, sk, nexthdr, daddr, saddr, 161 inet6_iif(skb), inet6_sdif(skb))) 162 continue; 163 164 if (atomic_read(&sk->sk_rmem_alloc) >= 165 READ_ONCE(sk->sk_rcvbuf)) { 166 atomic_inc(&sk->sk_drops); 167 continue; 168 } 169 170 delivered = true; 171 switch (nexthdr) { 172 case IPPROTO_ICMPV6: 173 filtered = icmpv6_filter(sk, skb); 174 break; 175 176 #if IS_ENABLED(CONFIG_IPV6_MIP6) 177 case IPPROTO_MH: 178 { 179 /* XXX: To validate MH only once for each packet, 180 * this is placed here. It should be after checking 181 * xfrm policy, however it doesn't. The checking xfrm 182 * policy is placed in rawv6_rcv() because it is 183 * required for each socket. 184 */ 185 mh_filter_t *filter; 186 187 filter = rcu_dereference(mh_filter); 188 filtered = filter ? (*filter)(sk, skb) : 0; 189 break; 190 } 191 #endif 192 default: 193 filtered = 0; 194 break; 195 } 196 197 if (filtered < 0) 198 break; 199 if (filtered == 0) { 200 struct sk_buff *clone = skb_clone(skb, GFP_ATOMIC); 201 202 /* Not releasing hash table! */ 203 if (clone) 204 rawv6_rcv(sk, clone); 205 } 206 } 207 rcu_read_unlock(); 208 return delivered; 209 } 210 211 bool raw6_local_deliver(struct sk_buff *skb, int nexthdr) 212 { 213 return ipv6_raw_deliver(skb, nexthdr); 214 } 215 216 /* This cleans up af_inet6 a bit. -DaveM */ 217 static int rawv6_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len) 218 { 219 struct inet_sock *inet = inet_sk(sk); 220 struct ipv6_pinfo *np = inet6_sk(sk); 221 struct sockaddr_in6 *addr = (struct sockaddr_in6 *) uaddr; 222 __be32 v4addr = 0; 223 int addr_type; 224 int err; 225 226 if (addr_len < SIN6_LEN_RFC2133) 227 return -EINVAL; 228 229 if (addr->sin6_family != AF_INET6) 230 return -EINVAL; 231 232 addr_type = ipv6_addr_type(&addr->sin6_addr); 233 234 /* Raw sockets are IPv6 only */ 235 if (addr_type == IPV6_ADDR_MAPPED) 236 return -EADDRNOTAVAIL; 237 238 lock_sock(sk); 239 240 err = -EINVAL; 241 if (sk->sk_state != TCP_CLOSE) 242 goto out; 243 244 rcu_read_lock(); 245 /* Check if the address belongs to the host. */ 246 if (addr_type != IPV6_ADDR_ANY) { 247 struct net_device *dev = NULL; 248 249 if (__ipv6_addr_needs_scope_id(addr_type)) { 250 if (addr_len >= sizeof(struct sockaddr_in6) && 251 addr->sin6_scope_id) { 252 /* Override any existing binding, if another 253 * one is supplied by user. 254 */ 255 sk->sk_bound_dev_if = addr->sin6_scope_id; 256 } 257 258 /* Binding to link-local address requires an interface */ 259 if (!sk->sk_bound_dev_if) 260 goto out_unlock; 261 } 262 263 if (sk->sk_bound_dev_if) { 264 err = -ENODEV; 265 dev = dev_get_by_index_rcu(sock_net(sk), 266 sk->sk_bound_dev_if); 267 if (!dev) 268 goto out_unlock; 269 } 270 271 /* ipv4 addr of the socket is invalid. Only the 272 * unspecified and mapped address have a v4 equivalent. 273 */ 274 v4addr = LOOPBACK4_IPV6; 275 if (!(addr_type & IPV6_ADDR_MULTICAST) && 276 !ipv6_can_nonlocal_bind(sock_net(sk), inet)) { 277 err = -EADDRNOTAVAIL; 278 if (!ipv6_chk_addr(sock_net(sk), &addr->sin6_addr, 279 dev, 0)) { 280 goto out_unlock; 281 } 282 } 283 } 284 285 inet->inet_rcv_saddr = inet->inet_saddr = v4addr; 286 sk->sk_v6_rcv_saddr = addr->sin6_addr; 287 if (!(addr_type & IPV6_ADDR_MULTICAST)) 288 np->saddr = addr->sin6_addr; 289 err = 0; 290 out_unlock: 291 rcu_read_unlock(); 292 out: 293 release_sock(sk); 294 return err; 295 } 296 297 static void rawv6_err(struct sock *sk, struct sk_buff *skb, 298 u8 type, u8 code, int offset, __be32 info) 299 { 300 bool recverr = inet6_test_bit(RECVERR6, sk); 301 struct ipv6_pinfo *np = inet6_sk(sk); 302 int err; 303 int harderr; 304 305 /* Report error on raw socket, if: 306 1. User requested recverr. 307 2. Socket is connected (otherwise the error indication 308 is useless without recverr and error is hard. 309 */ 310 if (!recverr && sk->sk_state != TCP_ESTABLISHED) 311 return; 312 313 harderr = icmpv6_err_convert(type, code, &err); 314 if (type == ICMPV6_PKT_TOOBIG) { 315 ip6_sk_update_pmtu(skb, sk, info); 316 harderr = (READ_ONCE(np->pmtudisc) == IPV6_PMTUDISC_DO); 317 } 318 if (type == NDISC_REDIRECT) { 319 ip6_sk_redirect(skb, sk); 320 return; 321 } 322 if (recverr) { 323 u8 *payload = skb->data; 324 if (!inet_test_bit(HDRINCL, sk)) 325 payload += offset; 326 ipv6_icmp_error(sk, skb, err, 0, ntohl(info), payload); 327 } 328 329 if (recverr || harderr) { 330 sk->sk_err = err; 331 sk_error_report(sk); 332 } 333 } 334 335 void raw6_icmp_error(struct sk_buff *skb, int nexthdr, 336 u8 type, u8 code, int inner_offset, __be32 info) 337 { 338 struct net *net = dev_net(skb->dev); 339 struct hlist_head *hlist; 340 struct sock *sk; 341 int hash; 342 343 hash = raw_hashfunc(net, nexthdr); 344 hlist = &raw_v6_hashinfo.ht[hash]; 345 rcu_read_lock(); 346 sk_for_each_rcu(sk, hlist) { 347 /* Note: ipv6_hdr(skb) != skb->data */ 348 const struct ipv6hdr *ip6h = (const struct ipv6hdr *)skb->data; 349 350 if (!raw_v6_match(net, sk, nexthdr, &ip6h->saddr, &ip6h->daddr, 351 inet6_iif(skb), inet6_iif(skb))) 352 continue; 353 rawv6_err(sk, skb, type, code, inner_offset, info); 354 } 355 rcu_read_unlock(); 356 } 357 358 static inline int rawv6_rcv_skb(struct sock *sk, struct sk_buff *skb) 359 { 360 enum skb_drop_reason reason; 361 362 if ((raw6_sk(sk)->checksum || rcu_access_pointer(sk->sk_filter)) && 363 skb_checksum_complete(skb)) { 364 atomic_inc(&sk->sk_drops); 365 sk_skb_reason_drop(sk, skb, SKB_DROP_REASON_SKB_CSUM); 366 return NET_RX_DROP; 367 } 368 369 /* Charge it to the socket. */ 370 skb_dst_drop(skb); 371 if (sock_queue_rcv_skb_reason(sk, skb, &reason) < 0) { 372 sk_skb_reason_drop(sk, skb, reason); 373 return NET_RX_DROP; 374 } 375 376 return 0; 377 } 378 379 /* 380 * This is next to useless... 381 * if we demultiplex in network layer we don't need the extra call 382 * just to queue the skb... 383 * maybe we could have the network decide upon a hint if it 384 * should call raw_rcv for demultiplexing 385 */ 386 int rawv6_rcv(struct sock *sk, struct sk_buff *skb) 387 { 388 struct inet_sock *inet = inet_sk(sk); 389 struct raw6_sock *rp = raw6_sk(sk); 390 391 if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) { 392 atomic_inc(&sk->sk_drops); 393 sk_skb_reason_drop(sk, skb, SKB_DROP_REASON_XFRM_POLICY); 394 return NET_RX_DROP; 395 } 396 nf_reset_ct(skb); 397 398 if (!rp->checksum) 399 skb->ip_summed = CHECKSUM_UNNECESSARY; 400 401 if (skb->ip_summed == CHECKSUM_COMPLETE) { 402 skb_postpull_rcsum(skb, skb_network_header(skb), 403 skb_network_header_len(skb)); 404 if (!csum_ipv6_magic(&ipv6_hdr(skb)->saddr, 405 &ipv6_hdr(skb)->daddr, 406 skb->len, inet->inet_num, skb->csum)) 407 skb->ip_summed = CHECKSUM_UNNECESSARY; 408 } 409 if (!skb_csum_unnecessary(skb)) 410 skb->csum = ~csum_unfold(csum_ipv6_magic(&ipv6_hdr(skb)->saddr, 411 &ipv6_hdr(skb)->daddr, 412 skb->len, 413 inet->inet_num, 0)); 414 415 if (inet_test_bit(HDRINCL, sk)) { 416 if (skb_checksum_complete(skb)) { 417 atomic_inc(&sk->sk_drops); 418 sk_skb_reason_drop(sk, skb, SKB_DROP_REASON_SKB_CSUM); 419 return NET_RX_DROP; 420 } 421 } 422 423 rawv6_rcv_skb(sk, skb); 424 return 0; 425 } 426 427 428 /* 429 * This should be easy, if there is something there 430 * we return it, otherwise we block. 431 */ 432 433 static int rawv6_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, 434 int flags, int *addr_len) 435 { 436 struct ipv6_pinfo *np = inet6_sk(sk); 437 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name); 438 struct sk_buff *skb; 439 size_t copied; 440 int err; 441 442 if (flags & MSG_OOB) 443 return -EOPNOTSUPP; 444 445 if (flags & MSG_ERRQUEUE) 446 return ipv6_recv_error(sk, msg, len, addr_len); 447 448 if (np->rxpmtu && np->rxopt.bits.rxpmtu) 449 return ipv6_recv_rxpmtu(sk, msg, len, addr_len); 450 451 skb = skb_recv_datagram(sk, flags, &err); 452 if (!skb) 453 goto out; 454 455 copied = skb->len; 456 if (copied > len) { 457 copied = len; 458 msg->msg_flags |= MSG_TRUNC; 459 } 460 461 if (skb_csum_unnecessary(skb)) { 462 err = skb_copy_datagram_msg(skb, 0, msg, copied); 463 } else if (msg->msg_flags&MSG_TRUNC) { 464 if (__skb_checksum_complete(skb)) 465 goto csum_copy_err; 466 err = skb_copy_datagram_msg(skb, 0, msg, copied); 467 } else { 468 err = skb_copy_and_csum_datagram_msg(skb, 0, msg); 469 if (err == -EINVAL) 470 goto csum_copy_err; 471 } 472 if (err) 473 goto out_free; 474 475 /* Copy the address. */ 476 if (sin6) { 477 sin6->sin6_family = AF_INET6; 478 sin6->sin6_port = 0; 479 sin6->sin6_addr = ipv6_hdr(skb)->saddr; 480 sin6->sin6_flowinfo = 0; 481 sin6->sin6_scope_id = ipv6_iface_scope_id(&sin6->sin6_addr, 482 inet6_iif(skb)); 483 *addr_len = sizeof(*sin6); 484 } 485 486 sock_recv_cmsgs(msg, sk, skb); 487 488 if (np->rxopt.all) 489 ip6_datagram_recv_ctl(sk, msg, skb); 490 491 err = copied; 492 if (flags & MSG_TRUNC) 493 err = skb->len; 494 495 out_free: 496 skb_free_datagram(sk, skb); 497 out: 498 return err; 499 500 csum_copy_err: 501 skb_kill_datagram(sk, skb, flags); 502 503 /* Error for blocking case is chosen to masquerade 504 as some normal condition. 505 */ 506 err = (flags&MSG_DONTWAIT) ? -EAGAIN : -EHOSTUNREACH; 507 goto out; 508 } 509 510 static int rawv6_push_pending_frames(struct sock *sk, struct flowi6 *fl6, 511 struct raw6_sock *rp) 512 { 513 struct ipv6_txoptions *opt; 514 struct sk_buff *skb; 515 int err = 0; 516 int offset; 517 int len; 518 int total_len; 519 __wsum tmp_csum; 520 __sum16 csum; 521 522 if (!rp->checksum) 523 goto send; 524 525 skb = skb_peek(&sk->sk_write_queue); 526 if (!skb) 527 goto out; 528 529 offset = rp->offset; 530 total_len = inet_sk(sk)->cork.base.length; 531 opt = inet6_sk(sk)->cork.opt; 532 total_len -= opt ? opt->opt_flen : 0; 533 534 if (offset >= total_len - 1) { 535 err = -EINVAL; 536 ip6_flush_pending_frames(sk); 537 goto out; 538 } 539 540 /* should be check HW csum miyazawa */ 541 if (skb_queue_len(&sk->sk_write_queue) == 1) { 542 /* 543 * Only one fragment on the socket. 544 */ 545 tmp_csum = skb->csum; 546 } else { 547 struct sk_buff *csum_skb = NULL; 548 tmp_csum = 0; 549 550 skb_queue_walk(&sk->sk_write_queue, skb) { 551 tmp_csum = csum_add(tmp_csum, skb->csum); 552 553 if (csum_skb) 554 continue; 555 556 len = skb->len - skb_transport_offset(skb); 557 if (offset >= len) { 558 offset -= len; 559 continue; 560 } 561 562 csum_skb = skb; 563 } 564 565 skb = csum_skb; 566 } 567 568 offset += skb_transport_offset(skb); 569 err = skb_copy_bits(skb, offset, &csum, 2); 570 if (err < 0) { 571 ip6_flush_pending_frames(sk); 572 goto out; 573 } 574 575 /* in case cksum was not initialized */ 576 if (unlikely(csum)) 577 tmp_csum = csum_sub(tmp_csum, csum_unfold(csum)); 578 579 csum = csum_ipv6_magic(&fl6->saddr, &fl6->daddr, 580 total_len, fl6->flowi6_proto, tmp_csum); 581 582 if (csum == 0 && fl6->flowi6_proto == IPPROTO_UDP) 583 csum = CSUM_MANGLED_0; 584 585 BUG_ON(skb_store_bits(skb, offset, &csum, 2)); 586 587 send: 588 err = ip6_push_pending_frames(sk); 589 out: 590 return err; 591 } 592 593 static int rawv6_send_hdrinc(struct sock *sk, struct msghdr *msg, int length, 594 struct flowi6 *fl6, struct dst_entry **dstp, 595 unsigned int flags, const struct sockcm_cookie *sockc) 596 { 597 struct net *net = sock_net(sk); 598 struct ipv6hdr *iph; 599 struct sk_buff *skb; 600 int err; 601 struct rt6_info *rt = dst_rt6_info(*dstp); 602 int hlen = LL_RESERVED_SPACE(rt->dst.dev); 603 int tlen = rt->dst.dev->needed_tailroom; 604 605 if (length > rt->dst.dev->mtu) { 606 ipv6_local_error(sk, EMSGSIZE, fl6, rt->dst.dev->mtu); 607 return -EMSGSIZE; 608 } 609 if (length < sizeof(struct ipv6hdr)) 610 return -EINVAL; 611 if (flags&MSG_PROBE) 612 goto out; 613 614 skb = sock_alloc_send_skb(sk, 615 length + hlen + tlen + 15, 616 flags & MSG_DONTWAIT, &err); 617 if (!skb) 618 goto error; 619 skb_reserve(skb, hlen); 620 621 skb->protocol = htons(ETH_P_IPV6); 622 skb->priority = READ_ONCE(sk->sk_priority); 623 skb->mark = sockc->mark; 624 skb_set_delivery_type_by_clockid(skb, sockc->transmit_time, sk->sk_clockid); 625 626 skb_put(skb, length); 627 skb_reset_network_header(skb); 628 iph = ipv6_hdr(skb); 629 630 skb->ip_summed = CHECKSUM_NONE; 631 632 skb_setup_tx_timestamp(skb, sockc->tsflags); 633 634 if (flags & MSG_CONFIRM) 635 skb_set_dst_pending_confirm(skb, 1); 636 637 skb->transport_header = skb->network_header; 638 err = memcpy_from_msg(iph, msg, length); 639 if (err) { 640 err = -EFAULT; 641 kfree_skb(skb); 642 goto error; 643 } 644 645 skb_dst_set(skb, &rt->dst); 646 *dstp = NULL; 647 648 /* if egress device is enslaved to an L3 master device pass the 649 * skb to its handler for processing 650 */ 651 skb = l3mdev_ip6_out(sk, skb); 652 if (unlikely(!skb)) 653 return 0; 654 655 /* Acquire rcu_read_lock() in case we need to use rt->rt6i_idev 656 * in the error path. Since skb has been freed, the dst could 657 * have been queued for deletion. 658 */ 659 rcu_read_lock(); 660 IP6_INC_STATS(net, rt->rt6i_idev, IPSTATS_MIB_OUTREQUESTS); 661 err = NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT, net, sk, skb, 662 NULL, rt->dst.dev, dst_output); 663 if (err > 0) 664 err = net_xmit_errno(err); 665 if (err) { 666 IP6_INC_STATS(net, rt->rt6i_idev, IPSTATS_MIB_OUTDISCARDS); 667 rcu_read_unlock(); 668 goto error_check; 669 } 670 rcu_read_unlock(); 671 out: 672 return 0; 673 674 error: 675 IP6_INC_STATS(net, rt->rt6i_idev, IPSTATS_MIB_OUTDISCARDS); 676 error_check: 677 if (err == -ENOBUFS && !inet6_test_bit(RECVERR6, sk)) 678 err = 0; 679 return err; 680 } 681 682 struct raw6_frag_vec { 683 struct msghdr *msg; 684 int hlen; 685 char c[4]; 686 }; 687 688 static int rawv6_probe_proto_opt(struct raw6_frag_vec *rfv, struct flowi6 *fl6) 689 { 690 int err = 0; 691 switch (fl6->flowi6_proto) { 692 case IPPROTO_ICMPV6: 693 rfv->hlen = 2; 694 err = memcpy_from_msg(rfv->c, rfv->msg, rfv->hlen); 695 if (!err) { 696 fl6->fl6_icmp_type = rfv->c[0]; 697 fl6->fl6_icmp_code = rfv->c[1]; 698 } 699 break; 700 case IPPROTO_MH: 701 rfv->hlen = 4; 702 err = memcpy_from_msg(rfv->c, rfv->msg, rfv->hlen); 703 if (!err) 704 fl6->fl6_mh_type = rfv->c[2]; 705 } 706 return err; 707 } 708 709 static int raw6_getfrag(void *from, char *to, int offset, int len, int odd, 710 struct sk_buff *skb) 711 { 712 struct raw6_frag_vec *rfv = from; 713 714 if (offset < rfv->hlen) { 715 int copy = min(rfv->hlen - offset, len); 716 717 if (skb->ip_summed == CHECKSUM_PARTIAL) 718 memcpy(to, rfv->c + offset, copy); 719 else 720 skb->csum = csum_block_add( 721 skb->csum, 722 csum_partial_copy_nocheck(rfv->c + offset, 723 to, copy), 724 odd); 725 726 odd = 0; 727 offset += copy; 728 to += copy; 729 len -= copy; 730 731 if (!len) 732 return 0; 733 } 734 735 offset -= rfv->hlen; 736 737 return ip_generic_getfrag(rfv->msg, to, offset, len, odd, skb); 738 } 739 740 static int rawv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) 741 { 742 struct ipv6_txoptions *opt_to_free = NULL; 743 struct ipv6_txoptions opt_space; 744 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name); 745 struct in6_addr *daddr, *final_p, final; 746 struct inet_sock *inet = inet_sk(sk); 747 struct ipv6_pinfo *np = inet6_sk(sk); 748 struct raw6_sock *rp = raw6_sk(sk); 749 struct ipv6_txoptions *opt = NULL; 750 struct ip6_flowlabel *flowlabel = NULL; 751 struct dst_entry *dst = NULL; 752 struct raw6_frag_vec rfv; 753 struct flowi6 fl6; 754 struct ipcm6_cookie ipc6; 755 int addr_len = msg->msg_namelen; 756 int hdrincl; 757 u16 proto; 758 int err; 759 760 /* Rough check on arithmetic overflow, 761 better check is made in ip6_append_data(). 762 */ 763 if (len > INT_MAX) 764 return -EMSGSIZE; 765 766 /* Mirror BSD error message compatibility */ 767 if (msg->msg_flags & MSG_OOB) 768 return -EOPNOTSUPP; 769 770 hdrincl = inet_test_bit(HDRINCL, sk); 771 772 /* 773 * Get and verify the address. 774 */ 775 memset(&fl6, 0, sizeof(fl6)); 776 777 fl6.flowi6_mark = READ_ONCE(sk->sk_mark); 778 fl6.flowi6_uid = sk->sk_uid; 779 780 ipcm6_init(&ipc6); 781 ipc6.sockc.tsflags = READ_ONCE(sk->sk_tsflags); 782 ipc6.sockc.mark = fl6.flowi6_mark; 783 784 if (sin6) { 785 if (addr_len < SIN6_LEN_RFC2133) 786 return -EINVAL; 787 788 if (sin6->sin6_family && sin6->sin6_family != AF_INET6) 789 return -EAFNOSUPPORT; 790 791 /* port is the proto value [0..255] carried in nexthdr */ 792 proto = ntohs(sin6->sin6_port); 793 794 if (!proto) 795 proto = inet->inet_num; 796 else if (proto != inet->inet_num && 797 inet->inet_num != IPPROTO_RAW) 798 return -EINVAL; 799 800 if (proto > 255) 801 return -EINVAL; 802 803 daddr = &sin6->sin6_addr; 804 if (inet6_test_bit(SNDFLOW, sk)) { 805 fl6.flowlabel = sin6->sin6_flowinfo&IPV6_FLOWINFO_MASK; 806 if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) { 807 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel); 808 if (IS_ERR(flowlabel)) 809 return -EINVAL; 810 } 811 } 812 813 /* 814 * Otherwise it will be difficult to maintain 815 * sk->sk_dst_cache. 816 */ 817 if (sk->sk_state == TCP_ESTABLISHED && 818 ipv6_addr_equal(daddr, &sk->sk_v6_daddr)) 819 daddr = &sk->sk_v6_daddr; 820 821 if (addr_len >= sizeof(struct sockaddr_in6) && 822 sin6->sin6_scope_id && 823 __ipv6_addr_needs_scope_id(__ipv6_addr_type(daddr))) 824 fl6.flowi6_oif = sin6->sin6_scope_id; 825 } else { 826 if (sk->sk_state != TCP_ESTABLISHED) 827 return -EDESTADDRREQ; 828 829 proto = inet->inet_num; 830 daddr = &sk->sk_v6_daddr; 831 fl6.flowlabel = np->flow_label; 832 } 833 834 if (fl6.flowi6_oif == 0) 835 fl6.flowi6_oif = sk->sk_bound_dev_if; 836 837 if (msg->msg_controllen) { 838 opt = &opt_space; 839 memset(opt, 0, sizeof(struct ipv6_txoptions)); 840 opt->tot_len = sizeof(struct ipv6_txoptions); 841 ipc6.opt = opt; 842 843 err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, &fl6, &ipc6); 844 if (err < 0) { 845 fl6_sock_release(flowlabel); 846 return err; 847 } 848 if ((fl6.flowlabel&IPV6_FLOWLABEL_MASK) && !flowlabel) { 849 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel); 850 if (IS_ERR(flowlabel)) 851 return -EINVAL; 852 } 853 if (!(opt->opt_nflen|opt->opt_flen)) 854 opt = NULL; 855 } 856 if (!opt) { 857 opt = txopt_get(np); 858 opt_to_free = opt; 859 } 860 if (flowlabel) 861 opt = fl6_merge_options(&opt_space, flowlabel, opt); 862 opt = ipv6_fixup_options(&opt_space, opt); 863 864 fl6.flowi6_proto = proto; 865 fl6.flowi6_mark = ipc6.sockc.mark; 866 867 if (!hdrincl) { 868 rfv.msg = msg; 869 rfv.hlen = 0; 870 err = rawv6_probe_proto_opt(&rfv, &fl6); 871 if (err) 872 goto out; 873 } 874 875 if (!ipv6_addr_any(daddr)) 876 fl6.daddr = *daddr; 877 else 878 fl6.daddr.s6_addr[15] = 0x1; /* :: means loopback (BSD'ism) */ 879 if (ipv6_addr_any(&fl6.saddr) && !ipv6_addr_any(&np->saddr)) 880 fl6.saddr = np->saddr; 881 882 final_p = fl6_update_dst(&fl6, opt, &final); 883 884 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr)) 885 fl6.flowi6_oif = READ_ONCE(np->mcast_oif); 886 else if (!fl6.flowi6_oif) 887 fl6.flowi6_oif = READ_ONCE(np->ucast_oif); 888 security_sk_classify_flow(sk, flowi6_to_flowi_common(&fl6)); 889 890 if (hdrincl) 891 fl6.flowi6_flags |= FLOWI_FLAG_KNOWN_NH; 892 893 if (ipc6.tclass < 0) 894 ipc6.tclass = np->tclass; 895 896 fl6.flowlabel = ip6_make_flowinfo(ipc6.tclass, fl6.flowlabel); 897 898 dst = ip6_dst_lookup_flow(sock_net(sk), sk, &fl6, final_p); 899 if (IS_ERR(dst)) { 900 err = PTR_ERR(dst); 901 goto out; 902 } 903 if (ipc6.hlimit < 0) 904 ipc6.hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst); 905 906 if (ipc6.dontfrag < 0) 907 ipc6.dontfrag = inet6_test_bit(DONTFRAG, sk); 908 909 if (msg->msg_flags&MSG_CONFIRM) 910 goto do_confirm; 911 912 back_from_confirm: 913 if (hdrincl) 914 err = rawv6_send_hdrinc(sk, msg, len, &fl6, &dst, 915 msg->msg_flags, &ipc6.sockc); 916 else { 917 ipc6.opt = opt; 918 lock_sock(sk); 919 err = ip6_append_data(sk, raw6_getfrag, &rfv, 920 len, 0, &ipc6, &fl6, dst_rt6_info(dst), 921 msg->msg_flags); 922 923 if (err) 924 ip6_flush_pending_frames(sk); 925 else if (!(msg->msg_flags & MSG_MORE)) 926 err = rawv6_push_pending_frames(sk, &fl6, rp); 927 release_sock(sk); 928 } 929 done: 930 dst_release(dst); 931 out: 932 fl6_sock_release(flowlabel); 933 txopt_put(opt_to_free); 934 return err < 0 ? err : len; 935 do_confirm: 936 if (msg->msg_flags & MSG_PROBE) 937 dst_confirm_neigh(dst, &fl6.daddr); 938 if (!(msg->msg_flags & MSG_PROBE) || len) 939 goto back_from_confirm; 940 err = 0; 941 goto done; 942 } 943 944 static int rawv6_seticmpfilter(struct sock *sk, int optname, 945 sockptr_t optval, int optlen) 946 { 947 switch (optname) { 948 case ICMPV6_FILTER: 949 if (optlen > sizeof(struct icmp6_filter)) 950 optlen = sizeof(struct icmp6_filter); 951 if (copy_from_sockptr(&raw6_sk(sk)->filter, optval, optlen)) 952 return -EFAULT; 953 return 0; 954 default: 955 return -ENOPROTOOPT; 956 } 957 958 return 0; 959 } 960 961 static int rawv6_geticmpfilter(struct sock *sk, int optname, 962 char __user *optval, int __user *optlen) 963 { 964 int len; 965 966 switch (optname) { 967 case ICMPV6_FILTER: 968 if (get_user(len, optlen)) 969 return -EFAULT; 970 if (len < 0) 971 return -EINVAL; 972 if (len > sizeof(struct icmp6_filter)) 973 len = sizeof(struct icmp6_filter); 974 if (put_user(len, optlen)) 975 return -EFAULT; 976 if (copy_to_user(optval, &raw6_sk(sk)->filter, len)) 977 return -EFAULT; 978 return 0; 979 default: 980 return -ENOPROTOOPT; 981 } 982 983 return 0; 984 } 985 986 987 static int do_rawv6_setsockopt(struct sock *sk, int level, int optname, 988 sockptr_t optval, unsigned int optlen) 989 { 990 struct raw6_sock *rp = raw6_sk(sk); 991 int val; 992 993 if (optlen < sizeof(val)) 994 return -EINVAL; 995 996 if (copy_from_sockptr(&val, optval, sizeof(val))) 997 return -EFAULT; 998 999 switch (optname) { 1000 case IPV6_HDRINCL: 1001 if (sk->sk_type != SOCK_RAW) 1002 return -EINVAL; 1003 inet_assign_bit(HDRINCL, sk, val); 1004 return 0; 1005 case IPV6_CHECKSUM: 1006 if (inet_sk(sk)->inet_num == IPPROTO_ICMPV6 && 1007 level == IPPROTO_IPV6) { 1008 /* 1009 * RFC3542 tells that IPV6_CHECKSUM socket 1010 * option in the IPPROTO_IPV6 level is not 1011 * allowed on ICMPv6 sockets. 1012 * If you want to set it, use IPPROTO_RAW 1013 * level IPV6_CHECKSUM socket option 1014 * (Linux extension). 1015 */ 1016 return -EINVAL; 1017 } 1018 1019 /* You may get strange result with a positive odd offset; 1020 RFC2292bis agrees with me. */ 1021 if (val > 0 && (val&1)) 1022 return -EINVAL; 1023 if (val < 0) { 1024 rp->checksum = 0; 1025 } else { 1026 rp->checksum = 1; 1027 rp->offset = val; 1028 } 1029 1030 return 0; 1031 1032 default: 1033 return -ENOPROTOOPT; 1034 } 1035 } 1036 1037 static int rawv6_setsockopt(struct sock *sk, int level, int optname, 1038 sockptr_t optval, unsigned int optlen) 1039 { 1040 switch (level) { 1041 case SOL_RAW: 1042 break; 1043 1044 case SOL_ICMPV6: 1045 if (inet_sk(sk)->inet_num != IPPROTO_ICMPV6) 1046 return -EOPNOTSUPP; 1047 return rawv6_seticmpfilter(sk, optname, optval, optlen); 1048 case SOL_IPV6: 1049 if (optname == IPV6_CHECKSUM || 1050 optname == IPV6_HDRINCL) 1051 break; 1052 fallthrough; 1053 default: 1054 return ipv6_setsockopt(sk, level, optname, optval, optlen); 1055 } 1056 1057 return do_rawv6_setsockopt(sk, level, optname, optval, optlen); 1058 } 1059 1060 static int do_rawv6_getsockopt(struct sock *sk, int level, int optname, 1061 char __user *optval, int __user *optlen) 1062 { 1063 struct raw6_sock *rp = raw6_sk(sk); 1064 int val, len; 1065 1066 if (get_user(len, optlen)) 1067 return -EFAULT; 1068 1069 switch (optname) { 1070 case IPV6_HDRINCL: 1071 val = inet_test_bit(HDRINCL, sk); 1072 break; 1073 case IPV6_CHECKSUM: 1074 /* 1075 * We allow getsockopt() for IPPROTO_IPV6-level 1076 * IPV6_CHECKSUM socket option on ICMPv6 sockets 1077 * since RFC3542 is silent about it. 1078 */ 1079 if (rp->checksum == 0) 1080 val = -1; 1081 else 1082 val = rp->offset; 1083 break; 1084 1085 default: 1086 return -ENOPROTOOPT; 1087 } 1088 1089 len = min_t(unsigned int, sizeof(int), len); 1090 1091 if (put_user(len, optlen)) 1092 return -EFAULT; 1093 if (copy_to_user(optval, &val, len)) 1094 return -EFAULT; 1095 return 0; 1096 } 1097 1098 static int rawv6_getsockopt(struct sock *sk, int level, int optname, 1099 char __user *optval, int __user *optlen) 1100 { 1101 switch (level) { 1102 case SOL_RAW: 1103 break; 1104 1105 case SOL_ICMPV6: 1106 if (inet_sk(sk)->inet_num != IPPROTO_ICMPV6) 1107 return -EOPNOTSUPP; 1108 return rawv6_geticmpfilter(sk, optname, optval, optlen); 1109 case SOL_IPV6: 1110 if (optname == IPV6_CHECKSUM || 1111 optname == IPV6_HDRINCL) 1112 break; 1113 fallthrough; 1114 default: 1115 return ipv6_getsockopt(sk, level, optname, optval, optlen); 1116 } 1117 1118 return do_rawv6_getsockopt(sk, level, optname, optval, optlen); 1119 } 1120 1121 static int rawv6_ioctl(struct sock *sk, int cmd, int *karg) 1122 { 1123 switch (cmd) { 1124 case SIOCOUTQ: { 1125 *karg = sk_wmem_alloc_get(sk); 1126 return 0; 1127 } 1128 case SIOCINQ: { 1129 struct sk_buff *skb; 1130 1131 spin_lock_bh(&sk->sk_receive_queue.lock); 1132 skb = skb_peek(&sk->sk_receive_queue); 1133 if (skb) 1134 *karg = skb->len; 1135 else 1136 *karg = 0; 1137 spin_unlock_bh(&sk->sk_receive_queue.lock); 1138 return 0; 1139 } 1140 1141 default: 1142 #ifdef CONFIG_IPV6_MROUTE 1143 return ip6mr_ioctl(sk, cmd, karg); 1144 #else 1145 return -ENOIOCTLCMD; 1146 #endif 1147 } 1148 } 1149 1150 #ifdef CONFIG_COMPAT 1151 static int compat_rawv6_ioctl(struct sock *sk, unsigned int cmd, unsigned long arg) 1152 { 1153 switch (cmd) { 1154 case SIOCOUTQ: 1155 case SIOCINQ: 1156 return -ENOIOCTLCMD; 1157 default: 1158 #ifdef CONFIG_IPV6_MROUTE 1159 return ip6mr_compat_ioctl(sk, cmd, compat_ptr(arg)); 1160 #else 1161 return -ENOIOCTLCMD; 1162 #endif 1163 } 1164 } 1165 #endif 1166 1167 static void rawv6_close(struct sock *sk, long timeout) 1168 { 1169 if (inet_sk(sk)->inet_num == IPPROTO_RAW) 1170 ip6_ra_control(sk, -1); 1171 ip6mr_sk_done(sk); 1172 sk_common_release(sk); 1173 } 1174 1175 static void raw6_destroy(struct sock *sk) 1176 { 1177 lock_sock(sk); 1178 ip6_flush_pending_frames(sk); 1179 release_sock(sk); 1180 } 1181 1182 static int rawv6_init_sk(struct sock *sk) 1183 { 1184 struct raw6_sock *rp = raw6_sk(sk); 1185 1186 switch (inet_sk(sk)->inet_num) { 1187 case IPPROTO_ICMPV6: 1188 rp->checksum = 1; 1189 rp->offset = 2; 1190 break; 1191 case IPPROTO_MH: 1192 rp->checksum = 1; 1193 rp->offset = 4; 1194 break; 1195 default: 1196 break; 1197 } 1198 return 0; 1199 } 1200 1201 struct proto rawv6_prot = { 1202 .name = "RAWv6", 1203 .owner = THIS_MODULE, 1204 .close = rawv6_close, 1205 .destroy = raw6_destroy, 1206 .connect = ip6_datagram_connect_v6_only, 1207 .disconnect = __udp_disconnect, 1208 .ioctl = rawv6_ioctl, 1209 .init = rawv6_init_sk, 1210 .setsockopt = rawv6_setsockopt, 1211 .getsockopt = rawv6_getsockopt, 1212 .sendmsg = rawv6_sendmsg, 1213 .recvmsg = rawv6_recvmsg, 1214 .bind = rawv6_bind, 1215 .backlog_rcv = rawv6_rcv_skb, 1216 .hash = raw_hash_sk, 1217 .unhash = raw_unhash_sk, 1218 .obj_size = sizeof(struct raw6_sock), 1219 .ipv6_pinfo_offset = offsetof(struct raw6_sock, inet6), 1220 .useroffset = offsetof(struct raw6_sock, filter), 1221 .usersize = sizeof_field(struct raw6_sock, filter), 1222 .h.raw_hash = &raw_v6_hashinfo, 1223 #ifdef CONFIG_COMPAT 1224 .compat_ioctl = compat_rawv6_ioctl, 1225 #endif 1226 .diag_destroy = raw_abort, 1227 }; 1228 1229 #ifdef CONFIG_PROC_FS 1230 static int raw6_seq_show(struct seq_file *seq, void *v) 1231 { 1232 if (v == SEQ_START_TOKEN) { 1233 seq_puts(seq, IPV6_SEQ_DGRAM_HEADER); 1234 } else { 1235 struct sock *sp = v; 1236 __u16 srcp = inet_sk(sp)->inet_num; 1237 ip6_dgram_sock_seq_show(seq, v, srcp, 0, 1238 raw_seq_private(seq)->bucket); 1239 } 1240 return 0; 1241 } 1242 1243 static const struct seq_operations raw6_seq_ops = { 1244 .start = raw_seq_start, 1245 .next = raw_seq_next, 1246 .stop = raw_seq_stop, 1247 .show = raw6_seq_show, 1248 }; 1249 1250 static int __net_init raw6_init_net(struct net *net) 1251 { 1252 if (!proc_create_net_data("raw6", 0444, net->proc_net, &raw6_seq_ops, 1253 sizeof(struct raw_iter_state), &raw_v6_hashinfo)) 1254 return -ENOMEM; 1255 1256 return 0; 1257 } 1258 1259 static void __net_exit raw6_exit_net(struct net *net) 1260 { 1261 remove_proc_entry("raw6", net->proc_net); 1262 } 1263 1264 static struct pernet_operations raw6_net_ops = { 1265 .init = raw6_init_net, 1266 .exit = raw6_exit_net, 1267 }; 1268 1269 int __init raw6_proc_init(void) 1270 { 1271 return register_pernet_subsys(&raw6_net_ops); 1272 } 1273 1274 void raw6_proc_exit(void) 1275 { 1276 unregister_pernet_subsys(&raw6_net_ops); 1277 } 1278 #endif /* CONFIG_PROC_FS */ 1279 1280 /* Same as inet6_dgram_ops, sans udp_poll. */ 1281 const struct proto_ops inet6_sockraw_ops = { 1282 .family = PF_INET6, 1283 .owner = THIS_MODULE, 1284 .release = inet6_release, 1285 .bind = inet6_bind, 1286 .connect = inet_dgram_connect, /* ok */ 1287 .socketpair = sock_no_socketpair, /* a do nothing */ 1288 .accept = sock_no_accept, /* a do nothing */ 1289 .getname = inet6_getname, 1290 .poll = datagram_poll, /* ok */ 1291 .ioctl = inet6_ioctl, /* must change */ 1292 .gettstamp = sock_gettstamp, 1293 .listen = sock_no_listen, /* ok */ 1294 .shutdown = inet_shutdown, /* ok */ 1295 .setsockopt = sock_common_setsockopt, /* ok */ 1296 .getsockopt = sock_common_getsockopt, /* ok */ 1297 .sendmsg = inet_sendmsg, /* ok */ 1298 .recvmsg = sock_common_recvmsg, /* ok */ 1299 .mmap = sock_no_mmap, 1300 #ifdef CONFIG_COMPAT 1301 .compat_ioctl = inet6_compat_ioctl, 1302 #endif 1303 }; 1304 1305 static struct inet_protosw rawv6_protosw = { 1306 .type = SOCK_RAW, 1307 .protocol = IPPROTO_IP, /* wild card */ 1308 .prot = &rawv6_prot, 1309 .ops = &inet6_sockraw_ops, 1310 .flags = INET_PROTOSW_REUSE, 1311 }; 1312 1313 int __init rawv6_init(void) 1314 { 1315 return inet6_register_protosw(&rawv6_protosw); 1316 } 1317 1318 void rawv6_exit(void) 1319 { 1320 inet6_unregister_protosw(&rawv6_protosw); 1321 } 1322