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 (__ipv6_addr_needs_scope_id(addr_type)) { 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 if (skb->protocol == htons(ETH_P_IPV6)) { 359 const struct ipv6hdr *ip6h = container_of((struct in6_addr *)(nh + serr->addr_offset), 360 struct ipv6hdr, daddr); 361 sin->sin6_addr = ip6h->daddr; 362 if (np->sndflow) 363 sin->sin6_flowinfo = ip6_flowinfo(ip6h); 364 sin->sin6_scope_id = 365 ipv6_iface_scope_id(&sin->sin6_addr, 366 IP6CB(skb)->iif); 367 } else { 368 ipv6_addr_set_v4mapped(*(__be32 *)(nh + serr->addr_offset), 369 &sin->sin6_addr); 370 sin->sin6_scope_id = 0; 371 } 372 } 373 374 memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err)); 375 sin = &errhdr.offender; 376 sin->sin6_family = AF_UNSPEC; 377 if (serr->ee.ee_origin != SO_EE_ORIGIN_LOCAL) { 378 sin->sin6_family = AF_INET6; 379 sin->sin6_flowinfo = 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 sin->sin6_scope_id = 385 ipv6_iface_scope_id(&sin->sin6_addr, 386 IP6CB(skb)->iif); 387 } else { 388 struct inet_sock *inet = inet_sk(sk); 389 390 ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr, 391 &sin->sin6_addr); 392 sin->sin6_scope_id = 0; 393 if (inet->cmsg_flags) 394 ip_cmsg_recv(msg, skb); 395 } 396 } 397 398 put_cmsg(msg, SOL_IPV6, IPV6_RECVERR, sizeof(errhdr), &errhdr); 399 400 /* Now we could try to dump offended packet options */ 401 402 msg->msg_flags |= MSG_ERRQUEUE; 403 err = copied; 404 405 /* Reset and regenerate socket error */ 406 spin_lock_bh(&sk->sk_error_queue.lock); 407 sk->sk_err = 0; 408 if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) { 409 sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno; 410 spin_unlock_bh(&sk->sk_error_queue.lock); 411 sk->sk_error_report(sk); 412 } else { 413 spin_unlock_bh(&sk->sk_error_queue.lock); 414 } 415 416 out_free_skb: 417 kfree_skb(skb); 418 out: 419 return err; 420 } 421 EXPORT_SYMBOL_GPL(ipv6_recv_error); 422 423 /* 424 * Handle IPV6_RECVPATHMTU 425 */ 426 int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len) 427 { 428 struct ipv6_pinfo *np = inet6_sk(sk); 429 struct sk_buff *skb; 430 struct sockaddr_in6 *sin; 431 struct ip6_mtuinfo mtu_info; 432 int err; 433 int copied; 434 435 err = -EAGAIN; 436 skb = xchg(&np->rxpmtu, NULL); 437 if (skb == NULL) 438 goto out; 439 440 copied = skb->len; 441 if (copied > len) { 442 msg->msg_flags |= MSG_TRUNC; 443 copied = len; 444 } 445 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied); 446 if (err) 447 goto out_free_skb; 448 449 sock_recv_timestamp(msg, sk, skb); 450 451 memcpy(&mtu_info, IP6CBMTU(skb), sizeof(mtu_info)); 452 453 sin = (struct sockaddr_in6 *)msg->msg_name; 454 if (sin) { 455 sin->sin6_family = AF_INET6; 456 sin->sin6_flowinfo = 0; 457 sin->sin6_port = 0; 458 sin->sin6_scope_id = mtu_info.ip6m_addr.sin6_scope_id; 459 sin->sin6_addr = mtu_info.ip6m_addr.sin6_addr; 460 } 461 462 put_cmsg(msg, SOL_IPV6, IPV6_PATHMTU, sizeof(mtu_info), &mtu_info); 463 464 err = copied; 465 466 out_free_skb: 467 kfree_skb(skb); 468 out: 469 return err; 470 } 471 472 473 int ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg, 474 struct sk_buff *skb) 475 { 476 struct ipv6_pinfo *np = inet6_sk(sk); 477 struct inet6_skb_parm *opt = IP6CB(skb); 478 unsigned char *nh = skb_network_header(skb); 479 480 if (np->rxopt.bits.rxinfo) { 481 struct in6_pktinfo src_info; 482 483 src_info.ipi6_ifindex = opt->iif; 484 src_info.ipi6_addr = ipv6_hdr(skb)->daddr; 485 put_cmsg(msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info); 486 } 487 488 if (np->rxopt.bits.rxhlim) { 489 int hlim = ipv6_hdr(skb)->hop_limit; 490 put_cmsg(msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim); 491 } 492 493 if (np->rxopt.bits.rxtclass) { 494 int tclass = ipv6_get_dsfield(ipv6_hdr(skb)); 495 put_cmsg(msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass); 496 } 497 498 if (np->rxopt.bits.rxflow) { 499 __be32 flowinfo = ip6_flowinfo((struct ipv6hdr *)nh); 500 if (flowinfo) 501 put_cmsg(msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo); 502 } 503 504 /* HbH is allowed only once */ 505 if (np->rxopt.bits.hopopts && opt->hop) { 506 u8 *ptr = nh + opt->hop; 507 put_cmsg(msg, SOL_IPV6, IPV6_HOPOPTS, (ptr[1]+1)<<3, ptr); 508 } 509 510 if (opt->lastopt && 511 (np->rxopt.bits.dstopts || np->rxopt.bits.srcrt)) { 512 /* 513 * Silly enough, but we need to reparse in order to 514 * report extension headers (except for HbH) 515 * in order. 516 * 517 * Also note that IPV6_RECVRTHDRDSTOPTS is NOT 518 * (and WILL NOT be) defined because 519 * IPV6_RECVDSTOPTS is more generic. --yoshfuji 520 */ 521 unsigned int off = sizeof(struct ipv6hdr); 522 u8 nexthdr = ipv6_hdr(skb)->nexthdr; 523 524 while (off <= opt->lastopt) { 525 unsigned int len; 526 u8 *ptr = nh + off; 527 528 switch (nexthdr) { 529 case IPPROTO_DSTOPTS: 530 nexthdr = ptr[0]; 531 len = (ptr[1] + 1) << 3; 532 if (np->rxopt.bits.dstopts) 533 put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, len, ptr); 534 break; 535 case IPPROTO_ROUTING: 536 nexthdr = ptr[0]; 537 len = (ptr[1] + 1) << 3; 538 if (np->rxopt.bits.srcrt) 539 put_cmsg(msg, SOL_IPV6, IPV6_RTHDR, len, ptr); 540 break; 541 case IPPROTO_AH: 542 nexthdr = ptr[0]; 543 len = (ptr[1] + 2) << 2; 544 break; 545 default: 546 nexthdr = ptr[0]; 547 len = (ptr[1] + 1) << 3; 548 break; 549 } 550 551 off += len; 552 } 553 } 554 555 /* socket options in old style */ 556 if (np->rxopt.bits.rxoinfo) { 557 struct in6_pktinfo src_info; 558 559 src_info.ipi6_ifindex = opt->iif; 560 src_info.ipi6_addr = ipv6_hdr(skb)->daddr; 561 put_cmsg(msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info); 562 } 563 if (np->rxopt.bits.rxohlim) { 564 int hlim = ipv6_hdr(skb)->hop_limit; 565 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim); 566 } 567 if (np->rxopt.bits.ohopopts && opt->hop) { 568 u8 *ptr = nh + opt->hop; 569 put_cmsg(msg, SOL_IPV6, IPV6_2292HOPOPTS, (ptr[1]+1)<<3, ptr); 570 } 571 if (np->rxopt.bits.odstopts && opt->dst0) { 572 u8 *ptr = nh + opt->dst0; 573 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr); 574 } 575 if (np->rxopt.bits.osrcrt && opt->srcrt) { 576 struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(nh + opt->srcrt); 577 put_cmsg(msg, SOL_IPV6, IPV6_2292RTHDR, (rthdr->hdrlen+1) << 3, rthdr); 578 } 579 if (np->rxopt.bits.odstopts && opt->dst1) { 580 u8 *ptr = nh + opt->dst1; 581 put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr); 582 } 583 if (np->rxopt.bits.rxorigdstaddr) { 584 struct sockaddr_in6 sin6; 585 __be16 *ports = (__be16 *) skb_transport_header(skb); 586 587 if (skb_transport_offset(skb) + 4 <= skb->len) { 588 /* All current transport protocols have the port numbers in the 589 * first four bytes of the transport header and this function is 590 * written with this assumption in mind. 591 */ 592 593 sin6.sin6_family = AF_INET6; 594 sin6.sin6_addr = ipv6_hdr(skb)->daddr; 595 sin6.sin6_port = ports[1]; 596 sin6.sin6_flowinfo = 0; 597 sin6.sin6_scope_id = 598 ipv6_iface_scope_id(&ipv6_hdr(skb)->daddr, 599 opt->iif); 600 601 put_cmsg(msg, SOL_IPV6, IPV6_ORIGDSTADDR, sizeof(sin6), &sin6); 602 } 603 } 604 return 0; 605 } 606 EXPORT_SYMBOL_GPL(ip6_datagram_recv_ctl); 607 608 int ip6_datagram_send_ctl(struct net *net, struct sock *sk, 609 struct msghdr *msg, struct flowi6 *fl6, 610 struct ipv6_txoptions *opt, 611 int *hlimit, int *tclass, int *dontfrag) 612 { 613 struct in6_pktinfo *src_info; 614 struct cmsghdr *cmsg; 615 struct ipv6_rt_hdr *rthdr; 616 struct ipv6_opt_hdr *hdr; 617 int len; 618 int err = 0; 619 620 for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) { 621 int addr_type; 622 623 if (!CMSG_OK(msg, cmsg)) { 624 err = -EINVAL; 625 goto exit_f; 626 } 627 628 if (cmsg->cmsg_level != SOL_IPV6) 629 continue; 630 631 switch (cmsg->cmsg_type) { 632 case IPV6_PKTINFO: 633 case IPV6_2292PKTINFO: 634 { 635 struct net_device *dev = NULL; 636 637 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct in6_pktinfo))) { 638 err = -EINVAL; 639 goto exit_f; 640 } 641 642 src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg); 643 644 if (src_info->ipi6_ifindex) { 645 if (fl6->flowi6_oif && 646 src_info->ipi6_ifindex != fl6->flowi6_oif) 647 return -EINVAL; 648 fl6->flowi6_oif = src_info->ipi6_ifindex; 649 } 650 651 addr_type = __ipv6_addr_type(&src_info->ipi6_addr); 652 653 rcu_read_lock(); 654 if (fl6->flowi6_oif) { 655 dev = dev_get_by_index_rcu(net, fl6->flowi6_oif); 656 if (!dev) { 657 rcu_read_unlock(); 658 return -ENODEV; 659 } 660 } else if (addr_type & IPV6_ADDR_LINKLOCAL) { 661 rcu_read_unlock(); 662 return -EINVAL; 663 } 664 665 if (addr_type != IPV6_ADDR_ANY) { 666 int strict = __ipv6_addr_src_scope(addr_type) <= IPV6_ADDR_SCOPE_LINKLOCAL; 667 if (!(inet_sk(sk)->freebind || inet_sk(sk)->transparent) && 668 !ipv6_chk_addr(net, &src_info->ipi6_addr, 669 strict ? dev : NULL, 0)) 670 err = -EINVAL; 671 else 672 fl6->saddr = src_info->ipi6_addr; 673 } 674 675 rcu_read_unlock(); 676 677 if (err) 678 goto exit_f; 679 680 break; 681 } 682 683 case IPV6_FLOWINFO: 684 if (cmsg->cmsg_len < CMSG_LEN(4)) { 685 err = -EINVAL; 686 goto exit_f; 687 } 688 689 if (fl6->flowlabel&IPV6_FLOWINFO_MASK) { 690 if ((fl6->flowlabel^*(__be32 *)CMSG_DATA(cmsg))&~IPV6_FLOWINFO_MASK) { 691 err = -EINVAL; 692 goto exit_f; 693 } 694 } 695 fl6->flowlabel = IPV6_FLOWINFO_MASK & *(__be32 *)CMSG_DATA(cmsg); 696 break; 697 698 case IPV6_2292HOPOPTS: 699 case IPV6_HOPOPTS: 700 if (opt->hopopt || cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) { 701 err = -EINVAL; 702 goto exit_f; 703 } 704 705 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg); 706 len = ((hdr->hdrlen + 1) << 3); 707 if (cmsg->cmsg_len < CMSG_LEN(len)) { 708 err = -EINVAL; 709 goto exit_f; 710 } 711 if (!ns_capable(net->user_ns, CAP_NET_RAW)) { 712 err = -EPERM; 713 goto exit_f; 714 } 715 opt->opt_nflen += len; 716 opt->hopopt = hdr; 717 break; 718 719 case IPV6_2292DSTOPTS: 720 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) { 721 err = -EINVAL; 722 goto exit_f; 723 } 724 725 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg); 726 len = ((hdr->hdrlen + 1) << 3); 727 if (cmsg->cmsg_len < CMSG_LEN(len)) { 728 err = -EINVAL; 729 goto exit_f; 730 } 731 if (!ns_capable(net->user_ns, CAP_NET_RAW)) { 732 err = -EPERM; 733 goto exit_f; 734 } 735 if (opt->dst1opt) { 736 err = -EINVAL; 737 goto exit_f; 738 } 739 opt->opt_flen += len; 740 opt->dst1opt = hdr; 741 break; 742 743 case IPV6_DSTOPTS: 744 case IPV6_RTHDRDSTOPTS: 745 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) { 746 err = -EINVAL; 747 goto exit_f; 748 } 749 750 hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg); 751 len = ((hdr->hdrlen + 1) << 3); 752 if (cmsg->cmsg_len < CMSG_LEN(len)) { 753 err = -EINVAL; 754 goto exit_f; 755 } 756 if (!ns_capable(net->user_ns, CAP_NET_RAW)) { 757 err = -EPERM; 758 goto exit_f; 759 } 760 if (cmsg->cmsg_type == IPV6_DSTOPTS) { 761 opt->opt_flen += len; 762 opt->dst1opt = hdr; 763 } else { 764 opt->opt_nflen += len; 765 opt->dst0opt = hdr; 766 } 767 break; 768 769 case IPV6_2292RTHDR: 770 case IPV6_RTHDR: 771 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_rt_hdr))) { 772 err = -EINVAL; 773 goto exit_f; 774 } 775 776 rthdr = (struct ipv6_rt_hdr *)CMSG_DATA(cmsg); 777 778 switch (rthdr->type) { 779 #if IS_ENABLED(CONFIG_IPV6_MIP6) 780 case IPV6_SRCRT_TYPE_2: 781 if (rthdr->hdrlen != 2 || 782 rthdr->segments_left != 1) { 783 err = -EINVAL; 784 goto exit_f; 785 } 786 break; 787 #endif 788 default: 789 err = -EINVAL; 790 goto exit_f; 791 } 792 793 len = ((rthdr->hdrlen + 1) << 3); 794 795 if (cmsg->cmsg_len < CMSG_LEN(len)) { 796 err = -EINVAL; 797 goto exit_f; 798 } 799 800 /* segments left must also match */ 801 if ((rthdr->hdrlen >> 1) != rthdr->segments_left) { 802 err = -EINVAL; 803 goto exit_f; 804 } 805 806 opt->opt_nflen += len; 807 opt->srcrt = rthdr; 808 809 if (cmsg->cmsg_type == IPV6_2292RTHDR && opt->dst1opt) { 810 int dsthdrlen = ((opt->dst1opt->hdrlen+1)<<3); 811 812 opt->opt_nflen += dsthdrlen; 813 opt->dst0opt = opt->dst1opt; 814 opt->dst1opt = NULL; 815 opt->opt_flen -= dsthdrlen; 816 } 817 818 break; 819 820 case IPV6_2292HOPLIMIT: 821 case IPV6_HOPLIMIT: 822 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) { 823 err = -EINVAL; 824 goto exit_f; 825 } 826 827 *hlimit = *(int *)CMSG_DATA(cmsg); 828 if (*hlimit < -1 || *hlimit > 0xff) { 829 err = -EINVAL; 830 goto exit_f; 831 } 832 833 break; 834 835 case IPV6_TCLASS: 836 { 837 int tc; 838 839 err = -EINVAL; 840 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) 841 goto exit_f; 842 843 tc = *(int *)CMSG_DATA(cmsg); 844 if (tc < -1 || tc > 0xff) 845 goto exit_f; 846 847 err = 0; 848 *tclass = tc; 849 850 break; 851 } 852 853 case IPV6_DONTFRAG: 854 { 855 int df; 856 857 err = -EINVAL; 858 if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) 859 goto exit_f; 860 861 df = *(int *)CMSG_DATA(cmsg); 862 if (df < 0 || df > 1) 863 goto exit_f; 864 865 err = 0; 866 *dontfrag = df; 867 868 break; 869 } 870 default: 871 LIMIT_NETDEBUG(KERN_DEBUG "invalid cmsg type: %d\n", 872 cmsg->cmsg_type); 873 err = -EINVAL; 874 goto exit_f; 875 } 876 } 877 878 exit_f: 879 return err; 880 } 881 EXPORT_SYMBOL_GPL(ip6_datagram_send_ctl); 882