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 <asm/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 int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) 44 { 45 struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr; 46 struct inet_sock *inet = inet_sk(sk); 47 struct ipv6_pinfo *np = inet6_sk(sk); 48 struct in6_addr *daddr, *final_p, final; 49 struct dst_entry *dst; 50 struct flowi6 fl6; 51 struct ip6_flowlabel *flowlabel = NULL; 52 struct ipv6_txoptions *opt; 53 int addr_type; 54 int err; 55 56 if (usin->sin6_family == AF_INET) { 57 if (__ipv6_only_sock(sk)) 58 return -EAFNOSUPPORT; 59 err = ip4_datagram_connect(sk, uaddr, addr_len); 60 goto ipv4_connected; 61 } 62 63 if (addr_len < SIN6_LEN_RFC2133) 64 return -EINVAL; 65 66 if (usin->sin6_family != AF_INET6) 67 return -EAFNOSUPPORT; 68 69 memset(&fl6, 0, sizeof(fl6)); 70 if (np->sndflow) { 71 fl6.flowlabel = usin->sin6_flowinfo&IPV6_FLOWINFO_MASK; 72 if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) { 73 flowlabel = fl6_sock_lookup(sk, fl6.flowlabel); 74 if (flowlabel == NULL) 75 return -EINVAL; 76 usin->sin6_addr = flowlabel->dst; 77 } 78 } 79 80 addr_type = ipv6_addr_type(&usin->sin6_addr); 81 82 if (addr_type == IPV6_ADDR_ANY) { 83 /* 84 * connect to self 85 */ 86 usin->sin6_addr.s6_addr[15] = 0x01; 87 } 88 89 daddr = &usin->sin6_addr; 90 91 if (addr_type == IPV6_ADDR_MAPPED) { 92 struct sockaddr_in sin; 93 94 if (__ipv6_only_sock(sk)) { 95 err = -ENETUNREACH; 96 goto out; 97 } 98 sin.sin_family = AF_INET; 99 sin.sin_addr.s_addr = daddr->s6_addr32[3]; 100 sin.sin_port = usin->sin6_port; 101 102 err = ip4_datagram_connect(sk, 103 (struct sockaddr *) &sin, 104 sizeof(sin)); 105 106 ipv4_connected: 107 if (err) 108 goto out; 109 110 ipv6_addr_set_v4mapped(inet->inet_daddr, &np->daddr); 111 112 if (ipv6_addr_any(&np->saddr) || 113 ipv6_mapped_addr_any(&np->saddr)) 114 ipv6_addr_set_v4mapped(inet->inet_saddr, &np->saddr); 115 116 if (ipv6_addr_any(&np->rcv_saddr) || 117 ipv6_mapped_addr_any(&np->rcv_saddr)) { 118 ipv6_addr_set_v4mapped(inet->inet_rcv_saddr, 119 &np->rcv_saddr); 120 if (sk->sk_prot->rehash) 121 sk->sk_prot->rehash(sk); 122 } 123 124 goto out; 125 } 126 127 if (addr_type&IPV6_ADDR_LINKLOCAL) { 128 if (addr_len >= sizeof(struct sockaddr_in6) && 129 usin->sin6_scope_id) { 130 if (sk->sk_bound_dev_if && 131 sk->sk_bound_dev_if != usin->sin6_scope_id) { 132 err = -EINVAL; 133 goto out; 134 } 135 sk->sk_bound_dev_if = usin->sin6_scope_id; 136 } 137 138 if (!sk->sk_bound_dev_if && (addr_type & IPV6_ADDR_MULTICAST)) 139 sk->sk_bound_dev_if = np->mcast_oif; 140 141 /* Connect to link-local address requires an interface */ 142 if (!sk->sk_bound_dev_if) { 143 err = -EINVAL; 144 goto out; 145 } 146 } 147 148 np->daddr = *daddr; 149 np->flow_label = fl6.flowlabel; 150 151 inet->inet_dport = usin->sin6_port; 152 153 /* 154 * Check for a route to destination an obtain the 155 * destination cache for it. 156 */ 157 158 fl6.flowi6_proto = sk->sk_protocol; 159 fl6.daddr = np->daddr; 160 fl6.saddr = np->saddr; 161 fl6.flowi6_oif = sk->sk_bound_dev_if; 162 fl6.flowi6_mark = sk->sk_mark; 163 fl6.fl6_dport = inet->inet_dport; 164 fl6.fl6_sport = inet->inet_sport; 165 166 if (!fl6.flowi6_oif && (addr_type&IPV6_ADDR_MULTICAST)) 167 fl6.flowi6_oif = np->mcast_oif; 168 169 security_sk_classify_flow(sk, flowi6_to_flowi(&fl6)); 170 171 opt = flowlabel ? flowlabel->opt : np->opt; 172 final_p = fl6_update_dst(&fl6, opt, &final); 173 174 dst = ip6_dst_lookup_flow(sk, &fl6, final_p, true); 175 err = 0; 176 if (IS_ERR(dst)) { 177 err = PTR_ERR(dst); 178 goto out; 179 } 180 181 /* source address lookup done in ip6_dst_lookup */ 182 183 if (ipv6_addr_any(&np->saddr)) 184 np->saddr = fl6.saddr; 185 186 if (ipv6_addr_any(&np->rcv_saddr)) { 187 np->rcv_saddr = fl6.saddr; 188 inet->inet_rcv_saddr = LOOPBACK4_IPV6; 189 if (sk->sk_prot->rehash) 190 sk->sk_prot->rehash(sk); 191 } 192 193 ip6_dst_store(sk, dst, 194 ipv6_addr_equal(&fl6.daddr, &np->daddr) ? 195 &np->daddr : NULL, 196 #ifdef CONFIG_IPV6_SUBTREES 197 ipv6_addr_equal(&fl6.saddr, &np->saddr) ? 198 &np->saddr : 199 #endif 200 NULL); 201 202 sk->sk_state = TCP_ESTABLISHED; 203 out: 204 fl6_sock_release(flowlabel); 205 return err; 206 } 207 EXPORT_SYMBOL_GPL(ip6_datagram_connect); 208 209 void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err, 210 __be16 port, u32 info, u8 *payload) 211 { 212 struct ipv6_pinfo *np = inet6_sk(sk); 213 struct icmp6hdr *icmph = icmp6_hdr(skb); 214 struct sock_exterr_skb *serr; 215 216 if (!np->recverr) 217 return; 218 219 skb = skb_clone(skb, GFP_ATOMIC); 220 if (!skb) 221 return; 222 223 skb->protocol = htons(ETH_P_IPV6); 224 225 serr = SKB_EXT_ERR(skb); 226 serr->ee.ee_errno = err; 227 serr->ee.ee_origin = SO_EE_ORIGIN_ICMP6; 228 serr->ee.ee_type = icmph->icmp6_type; 229 serr->ee.ee_code = icmph->icmp6_code; 230 serr->ee.ee_pad = 0; 231 serr->ee.ee_info = info; 232 serr->ee.ee_data = 0; 233 serr->addr_offset = (u8 *)&(((struct ipv6hdr *)(icmph + 1))->daddr) - 234 skb_network_header(skb); 235 serr->port = port; 236 237 __skb_pull(skb, payload - skb->data); 238 skb_reset_transport_header(skb); 239 240 if (sock_queue_err_skb(sk, skb)) 241 kfree_skb(skb); 242 } 243 244 void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info) 245 { 246 struct ipv6_pinfo *np = inet6_sk(sk); 247 struct sock_exterr_skb *serr; 248 struct ipv6hdr *iph; 249 struct sk_buff *skb; 250 251 if (!np->recverr) 252 return; 253 254 skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC); 255 if (!skb) 256 return; 257 258 skb->protocol = htons(ETH_P_IPV6); 259 260 skb_put(skb, sizeof(struct ipv6hdr)); 261 skb_reset_network_header(skb); 262 iph = ipv6_hdr(skb); 263 iph->daddr = fl6->daddr; 264 265 serr = SKB_EXT_ERR(skb); 266 serr->ee.ee_errno = err; 267 serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL; 268 serr->ee.ee_type = 0; 269 serr->ee.ee_code = 0; 270 serr->ee.ee_pad = 0; 271 serr->ee.ee_info = info; 272 serr->ee.ee_data = 0; 273 serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb); 274 serr->port = fl6->fl6_dport; 275 276 __skb_pull(skb, skb_tail_pointer(skb) - skb->data); 277 skb_reset_transport_header(skb); 278 279 if (sock_queue_err_skb(sk, skb)) 280 kfree_skb(skb); 281 } 282 283 void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu) 284 { 285 struct ipv6_pinfo *np = inet6_sk(sk); 286 struct ipv6hdr *iph; 287 struct sk_buff *skb; 288 struct ip6_mtuinfo *mtu_info; 289 290 if (!np->rxopt.bits.rxpmtu) 291 return; 292 293 skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC); 294 if (!skb) 295 return; 296 297 skb_put(skb, sizeof(struct ipv6hdr)); 298 skb_reset_network_header(skb); 299 iph = ipv6_hdr(skb); 300 iph->daddr = fl6->daddr; 301 302 mtu_info = IP6CBMTU(skb); 303 304 mtu_info->ip6m_mtu = mtu; 305 mtu_info->ip6m_addr.sin6_family = AF_INET6; 306 mtu_info->ip6m_addr.sin6_port = 0; 307 mtu_info->ip6m_addr.sin6_flowinfo = 0; 308 mtu_info->ip6m_addr.sin6_scope_id = fl6->flowi6_oif; 309 mtu_info->ip6m_addr.sin6_addr = ipv6_hdr(skb)->daddr; 310 311 __skb_pull(skb, skb_tail_pointer(skb) - skb->data); 312 skb_reset_transport_header(skb); 313 314 skb = xchg(&np->rxpmtu, skb); 315 kfree_skb(skb); 316 } 317 318 /* 319 * Handle MSG_ERRQUEUE 320 */ 321 int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len) 322 { 323 struct ipv6_pinfo *np = inet6_sk(sk); 324 struct sock_exterr_skb *serr; 325 struct sk_buff *skb, *skb2; 326 struct sockaddr_in6 *sin; 327 struct { 328 struct sock_extended_err ee; 329 struct sockaddr_in6 offender; 330 } errhdr; 331 int err; 332 int copied; 333 334 err = -EAGAIN; 335 skb = skb_dequeue(&sk->sk_error_queue); 336 if (skb == NULL) 337 goto out; 338 339 copied = skb->len; 340 if (copied > len) { 341 msg->msg_flags |= MSG_TRUNC; 342 copied = len; 343 } 344 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied); 345 if (err) 346 goto out_free_skb; 347 348 sock_recv_timestamp(msg, sk, skb); 349 350 serr = SKB_EXT_ERR(skb); 351 352 sin = (struct sockaddr_in6 *)msg->msg_name; 353 if (sin) { 354 const unsigned char *nh = skb_network_header(skb); 355 sin->sin6_family = AF_INET6; 356 sin->sin6_flowinfo = 0; 357 sin->sin6_port = serr->port; 358 sin->sin6_scope_id = 0; 359 if (skb->protocol == htons(ETH_P_IPV6)) { 360 const struct ipv6hdr *ip6h = container_of((struct in6_addr *)(nh + serr->addr_offset), 361 struct ipv6hdr, daddr); 362 sin->sin6_addr = ip6h->daddr; 363 if (np->sndflow) 364 sin->sin6_flowinfo = ip6_flowinfo(ip6h); 365 if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL) 366 sin->sin6_scope_id = IP6CB(skb)->iif; 367 } else { 368 ipv6_addr_set_v4mapped(*(__be32 *)(nh + serr->addr_offset), 369 &sin->sin6_addr); 370 } 371 } 372 373 memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err)); 374 sin = &errhdr.offender; 375 sin->sin6_family = AF_UNSPEC; 376 if (serr->ee.ee_origin != SO_EE_ORIGIN_LOCAL) { 377 sin->sin6_family = AF_INET6; 378 sin->sin6_flowinfo = 0; 379 sin->sin6_scope_id = 0; 380 if (skb->protocol == htons(ETH_P_IPV6)) { 381 sin->sin6_addr = ipv6_hdr(skb)->saddr; 382 if (np->rxopt.all) 383 ip6_datagram_recv_ctl(sk, msg, skb); 384 if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL) 385 sin->sin6_scope_id = IP6CB(skb)->iif; 386 } else { 387 struct inet_sock *inet = inet_sk(sk); 388 389 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr, 390 &sin->sin6_addr); 391 if (inet->cmsg_flags) 392 ip_cmsg_recv(msg, skb); 393 } 394 } 395 396 put_cmsg(msg, SOL_IPV6, IPV6_RECVERR, sizeof(errhdr), &errhdr); 397 398 /* Now we could try to dump offended packet options */ 399 400 msg->msg_flags |= MSG_ERRQUEUE; 401 err = copied; 402 403 /* Reset and regenerate socket error */ 404 spin_lock_bh(&sk->sk_error_queue.lock); 405 sk->sk_err = 0; 406 if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) { 407 sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno; 408 spin_unlock_bh(&sk->sk_error_queue.lock); 409 sk->sk_error_report(sk); 410 } else { 411 spin_unlock_bh(&sk->sk_error_queue.lock); 412 } 413 414 out_free_skb: 415 kfree_skb(skb); 416 out: 417 return err; 418 } 419 EXPORT_SYMBOL_GPL(ipv6_recv_error); 420 421 /* 422 * Handle IPV6_RECVPATHMTU 423 */ 424 int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len) 425 { 426 struct ipv6_pinfo *np = inet6_sk(sk); 427 struct sk_buff *skb; 428 struct sockaddr_in6 *sin; 429 struct ip6_mtuinfo mtu_info; 430 int err; 431 int copied; 432 433 err = -EAGAIN; 434 skb = xchg(&np->rxpmtu, NULL); 435 if (skb == NULL) 436 goto out; 437 438 copied = skb->len; 439 if (copied > len) { 440 msg->msg_flags |= MSG_TRUNC; 441 copied = len; 442 } 443 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied); 444 if (err) 445 goto out_free_skb; 446 447 sock_recv_timestamp(msg, sk, skb); 448 449 memcpy(&mtu_info, IP6CBMTU(skb), sizeof(mtu_info)); 450 451 sin = (struct sockaddr_in6 *)msg->msg_name; 452 if (sin) { 453 sin->sin6_family = AF_INET6; 454 sin->sin6_flowinfo = 0; 455 sin->sin6_port = 0; 456 sin->sin6_scope_id = mtu_info.ip6m_addr.sin6_scope_id; 457 sin->sin6_addr = mtu_info.ip6m_addr.sin6_addr; 458 } 459 460 put_cmsg(msg, SOL_IPV6, IPV6_PATHMTU, sizeof(mtu_info), &mtu_info); 461 462 err = copied; 463 464 out_free_skb: 465 kfree_skb(skb); 466 out: 467 return err; 468 } 469 470 471 int ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg, 472 struct sk_buff *skb) 473 { 474 struct ipv6_pinfo *np = inet6_sk(sk); 475 struct inet6_skb_parm *opt = IP6CB(skb); 476 unsigned char *nh = skb_network_header(skb); 477 478 if (np->rxopt.bits.rxinfo) { 479 struct in6_pktinfo src_info; 480 481 src_info.ipi6_ifindex = opt->iif; 482 src_info.ipi6_addr = ipv6_hdr(skb)->daddr; 483 put_cmsg(msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info); 484 } 485 486 if (np->rxopt.bits.rxhlim) { 487 int hlim = ipv6_hdr(skb)->hop_limit; 488 put_cmsg(msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim); 489 } 490 491 if (np->rxopt.bits.rxtclass) { 492 int tclass = ipv6_get_dsfield(ipv6_hdr(skb)); 493 put_cmsg(msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass); 494 } 495 496 if (np->rxopt.bits.rxflow) { 497 __be32 flowinfo = ip6_flowinfo((struct ipv6hdr *)nh); 498 if (flowinfo) 499 put_cmsg(msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo); 500 } 501 502 /* HbH is allowed only once */ 503 if (np->rxopt.bits.hopopts && opt->hop) { 504 u8 *ptr = nh + opt->hop; 505 put_cmsg(msg, SOL_IPV6, IPV6_HOPOPTS, (ptr[1]+1)<<3, ptr); 506 } 507 508 if (opt->lastopt && 509 (np->rxopt.bits.dstopts || np->rxopt.bits.srcrt)) { 510 /* 511 * Silly enough, but we need to reparse in order to 512 * report extension headers (except for HbH) 513 * in order. 514 * 515 * Also note that IPV6_RECVRTHDRDSTOPTS is NOT 516 * (and WILL NOT be) defined because 517 * IPV6_RECVDSTOPTS is more generic. --yoshfuji 518 */ 519 unsigned int off = sizeof(struct ipv6hdr); 520 u8 nexthdr = ipv6_hdr(skb)->nexthdr; 521 522 while (off <= opt->lastopt) { 523 unsigned int len; 524 u8 *ptr = nh + off; 525 526 switch (nexthdr) { 527 case IPPROTO_DSTOPTS: 528 nexthdr = ptr[0]; 529 len = (ptr[1] + 1) << 3; 530 if (np->rxopt.bits.dstopts) 531 put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, len, ptr); 532 break; 533 case IPPROTO_ROUTING: 534 nexthdr = ptr[0]; 535 len = (ptr[1] + 1) << 3; 536 if (np->rxopt.bits.srcrt) 537 put_cmsg(msg, SOL_IPV6, IPV6_RTHDR, len, ptr); 538 break; 539 case IPPROTO_AH: 540 nexthdr = ptr[0]; 541 len = (ptr[1] + 2) << 2; 542 break; 543 default: 544 nexthdr = ptr[0]; 545 len = (ptr[1] + 1) << 3; 546 break; 547 } 548 549 off += len; 550 } 551 } 552 553 /* socket options in old style */ 554 if (np->rxopt.bits.rxoinfo) { 555 struct in6_pktinfo src_info; 556 557 src_info.ipi6_ifindex = opt->iif; 558 src_info.ipi6_addr = ipv6_hdr(skb)->daddr; 559 put_cmsg(msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info); 560 } 561 if (np->rxopt.bits.rxohlim) { 562 int hlim = ipv6_hdr(skb)->hop_limit; 563 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim); 564 } 565 if (np->rxopt.bits.ohopopts && opt->hop) { 566 u8 *ptr = nh + opt->hop; 567 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPOPTS, (ptr[1]+1)<<3, ptr); 568 } 569 if (np->rxopt.bits.odstopts && opt->dst0) { 570 u8 *ptr = nh + opt->dst0; 571 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr); 572 } 573 if (np->rxopt.bits.osrcrt && opt->srcrt) { 574 struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(nh + opt->srcrt); 575 put_cmsg(msg, SOL_IPV6, IPV6_2292RTHDR, (rthdr->hdrlen+1) << 3, rthdr); 576 } 577 if (np->rxopt.bits.odstopts && opt->dst1) { 578 u8 *ptr = nh + opt->dst1; 579 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr); 580 } 581 if (np->rxopt.bits.rxorigdstaddr) { 582 struct sockaddr_in6 sin6; 583 __be16 *ports = (__be16 *) skb_transport_header(skb); 584 585 if (skb_transport_offset(skb) + 4 <= skb->len) { 586 /* All current transport protocols have the port numbers in the 587 * first four bytes of the transport header and this function is 588 * written with this assumption in mind. 589 */ 590 591 sin6.sin6_family = AF_INET6; 592 sin6.sin6_addr = ipv6_hdr(skb)->daddr; 593 sin6.sin6_port = ports[1]; 594 sin6.sin6_flowinfo = 0; 595 sin6.sin6_scope_id = 0; 596 597 put_cmsg(msg, SOL_IPV6, IPV6_ORIGDSTADDR, sizeof(sin6), &sin6); 598 } 599 } 600 return 0; 601 } 602 EXPORT_SYMBOL_GPL(ip6_datagram_recv_ctl); 603 604 int ip6_datagram_send_ctl(struct net *net, struct sock *sk, 605 struct msghdr *msg, struct flowi6 *fl6, 606 struct ipv6_txoptions *opt, 607 int *hlimit, int *tclass, int *dontfrag) 608 { 609 struct in6_pktinfo *src_info; 610 struct cmsghdr *cmsg; 611 struct ipv6_rt_hdr *rthdr; 612 struct ipv6_opt_hdr *hdr; 613 int len; 614 int err = 0; 615 616 for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) { 617 int addr_type; 618 619 if (!CMSG_OK(msg, cmsg)) { 620 err = -EINVAL; 621 goto exit_f; 622 } 623 624 if (cmsg->cmsg_level != SOL_IPV6) 625 continue; 626 627 switch (cmsg->cmsg_type) { 628 case IPV6_PKTINFO: 629 case IPV6_2292PKTINFO: 630 { 631 struct net_device *dev = NULL; 632 633 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct in6_pktinfo))) { 634 err = -EINVAL; 635 goto exit_f; 636 } 637 638 src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg); 639 640 if (src_info->ipi6_ifindex) { 641 if (fl6->flowi6_oif && 642 src_info->ipi6_ifindex != fl6->flowi6_oif) 643 return -EINVAL; 644 fl6->flowi6_oif = src_info->ipi6_ifindex; 645 } 646 647 addr_type = __ipv6_addr_type(&src_info->ipi6_addr); 648 649 rcu_read_lock(); 650 if (fl6->flowi6_oif) { 651 dev = dev_get_by_index_rcu(net, fl6->flowi6_oif); 652 if (!dev) { 653 rcu_read_unlock(); 654 return -ENODEV; 655 } 656 } else if (addr_type & IPV6_ADDR_LINKLOCAL) { 657 rcu_read_unlock(); 658 return -EINVAL; 659 } 660 661 if (addr_type != IPV6_ADDR_ANY) { 662 int strict = __ipv6_addr_src_scope(addr_type) <= IPV6_ADDR_SCOPE_LINKLOCAL; 663 if (!(inet_sk(sk)->freebind || inet_sk(sk)->transparent) && 664 !ipv6_chk_addr(net, &src_info->ipi6_addr, 665 strict ? dev : NULL, 0)) 666 err = -EINVAL; 667 else 668 fl6->saddr = src_info->ipi6_addr; 669 } 670 671 rcu_read_unlock(); 672 673 if (err) 674 goto exit_f; 675 676 break; 677 } 678 679 case IPV6_FLOWINFO: 680 if (cmsg->cmsg_len < CMSG_LEN(4)) { 681 err = -EINVAL; 682 goto exit_f; 683 } 684 685 if (fl6->flowlabel&IPV6_FLOWINFO_MASK) { 686 if ((fl6->flowlabel^*(__be32 *)CMSG_DATA(cmsg))&~IPV6_FLOWINFO_MASK) { 687 err = -EINVAL; 688 goto exit_f; 689 } 690 } 691 fl6->flowlabel = IPV6_FLOWINFO_MASK & *(__be32 *)CMSG_DATA(cmsg); 692 break; 693 694 case IPV6_2292HOPOPTS: 695 case IPV6_HOPOPTS: 696 if (opt->hopopt || cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) { 697 err = -EINVAL; 698 goto exit_f; 699 } 700 701 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg); 702 len = ((hdr->hdrlen + 1) << 3); 703 if (cmsg->cmsg_len < CMSG_LEN(len)) { 704 err = -EINVAL; 705 goto exit_f; 706 } 707 if (!ns_capable(net->user_ns, CAP_NET_RAW)) { 708 err = -EPERM; 709 goto exit_f; 710 } 711 opt->opt_nflen += len; 712 opt->hopopt = hdr; 713 break; 714 715 case IPV6_2292DSTOPTS: 716 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) { 717 err = -EINVAL; 718 goto exit_f; 719 } 720 721 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg); 722 len = ((hdr->hdrlen + 1) << 3); 723 if (cmsg->cmsg_len < CMSG_LEN(len)) { 724 err = -EINVAL; 725 goto exit_f; 726 } 727 if (!ns_capable(net->user_ns, CAP_NET_RAW)) { 728 err = -EPERM; 729 goto exit_f; 730 } 731 if (opt->dst1opt) { 732 err = -EINVAL; 733 goto exit_f; 734 } 735 opt->opt_flen += len; 736 opt->dst1opt = hdr; 737 break; 738 739 case IPV6_DSTOPTS: 740 case IPV6_RTHDRDSTOPTS: 741 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) { 742 err = -EINVAL; 743 goto exit_f; 744 } 745 746 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg); 747 len = ((hdr->hdrlen + 1) << 3); 748 if (cmsg->cmsg_len < CMSG_LEN(len)) { 749 err = -EINVAL; 750 goto exit_f; 751 } 752 if (!ns_capable(net->user_ns, CAP_NET_RAW)) { 753 err = -EPERM; 754 goto exit_f; 755 } 756 if (cmsg->cmsg_type == IPV6_DSTOPTS) { 757 opt->opt_flen += len; 758 opt->dst1opt = hdr; 759 } else { 760 opt->opt_nflen += len; 761 opt->dst0opt = hdr; 762 } 763 break; 764 765 case IPV6_2292RTHDR: 766 case IPV6_RTHDR: 767 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_rt_hdr))) { 768 err = -EINVAL; 769 goto exit_f; 770 } 771 772 rthdr = (struct ipv6_rt_hdr *)CMSG_DATA(cmsg); 773 774 switch (rthdr->type) { 775 #if IS_ENABLED(CONFIG_IPV6_MIP6) 776 case IPV6_SRCRT_TYPE_2: 777 if (rthdr->hdrlen != 2 || 778 rthdr->segments_left != 1) { 779 err = -EINVAL; 780 goto exit_f; 781 } 782 break; 783 #endif 784 default: 785 err = -EINVAL; 786 goto exit_f; 787 } 788 789 len = ((rthdr->hdrlen + 1) << 3); 790 791 if (cmsg->cmsg_len < CMSG_LEN(len)) { 792 err = -EINVAL; 793 goto exit_f; 794 } 795 796 /* segments left must also match */ 797 if ((rthdr->hdrlen >> 1) != rthdr->segments_left) { 798 err = -EINVAL; 799 goto exit_f; 800 } 801 802 opt->opt_nflen += len; 803 opt->srcrt = rthdr; 804 805 if (cmsg->cmsg_type == IPV6_2292RTHDR && opt->dst1opt) { 806 int dsthdrlen = ((opt->dst1opt->hdrlen+1)<<3); 807 808 opt->opt_nflen += dsthdrlen; 809 opt->dst0opt = opt->dst1opt; 810 opt->dst1opt = NULL; 811 opt->opt_flen -= dsthdrlen; 812 } 813 814 break; 815 816 case IPV6_2292HOPLIMIT: 817 case IPV6_HOPLIMIT: 818 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) { 819 err = -EINVAL; 820 goto exit_f; 821 } 822 823 *hlimit = *(int *)CMSG_DATA(cmsg); 824 if (*hlimit < -1 || *hlimit > 0xff) { 825 err = -EINVAL; 826 goto exit_f; 827 } 828 829 break; 830 831 case IPV6_TCLASS: 832 { 833 int tc; 834 835 err = -EINVAL; 836 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) 837 goto exit_f; 838 839 tc = *(int *)CMSG_DATA(cmsg); 840 if (tc < -1 || tc > 0xff) 841 goto exit_f; 842 843 err = 0; 844 *tclass = tc; 845 846 break; 847 } 848 849 case IPV6_DONTFRAG: 850 { 851 int df; 852 853 err = -EINVAL; 854 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) 855 goto exit_f; 856 857 df = *(int *)CMSG_DATA(cmsg); 858 if (df < 0 || df > 1) 859 goto exit_f; 860 861 err = 0; 862 *dontfrag = df; 863 864 break; 865 } 866 default: 867 LIMIT_NETDEBUG(KERN_DEBUG "invalid cmsg type: %d\n", 868 cmsg->cmsg_type); 869 err = -EINVAL; 870 goto exit_f; 871 } 872 } 873 874 exit_f: 875 return err; 876 } 877 EXPORT_SYMBOL_GPL(ip6_datagram_send_ctl); 878