1 /* 2 * INET An implementation of the TCP/IP protocol suite for the LINUX 3 * operating system. INET is implemented using the BSD Socket 4 * interface as the means of communication with the user level. 5 * 6 * RAW - implementation of IP "raw" sockets. 7 * 8 * Authors: Ross Biro 9 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> 10 * 11 * Fixes: 12 * Alan Cox : verify_area() fixed up 13 * Alan Cox : ICMP error handling 14 * Alan Cox : EMSGSIZE if you send too big a packet 15 * Alan Cox : Now uses generic datagrams and shared 16 * skbuff library. No more peek crashes, 17 * no more backlogs 18 * Alan Cox : Checks sk->broadcast. 19 * Alan Cox : Uses skb_free_datagram/skb_copy_datagram 20 * Alan Cox : Raw passes ip options too 21 * Alan Cox : Setsocketopt added 22 * Alan Cox : Fixed error return for broadcasts 23 * Alan Cox : Removed wake_up calls 24 * Alan Cox : Use ttl/tos 25 * Alan Cox : Cleaned up old debugging 26 * Alan Cox : Use new kernel side addresses 27 * Arnt Gulbrandsen : Fixed MSG_DONTROUTE in raw sockets. 28 * Alan Cox : BSD style RAW socket demultiplexing. 29 * Alan Cox : Beginnings of mrouted support. 30 * Alan Cox : Added IP_HDRINCL option. 31 * Alan Cox : Skip broadcast check if BSDism set. 32 * David S. Miller : New socket lookup architecture. 33 * 34 * This program is free software; you can redistribute it and/or 35 * modify it under the terms of the GNU General Public License 36 * as published by the Free Software Foundation; either version 37 * 2 of the License, or (at your option) any later version. 38 */ 39 40 #include <linux/types.h> 41 #include <linux/atomic.h> 42 #include <asm/byteorder.h> 43 #include <asm/current.h> 44 #include <asm/uaccess.h> 45 #include <asm/ioctls.h> 46 #include <linux/stddef.h> 47 #include <linux/slab.h> 48 #include <linux/errno.h> 49 #include <linux/kernel.h> 50 #include <linux/export.h> 51 #include <linux/spinlock.h> 52 #include <linux/sockios.h> 53 #include <linux/socket.h> 54 #include <linux/in.h> 55 #include <linux/mroute.h> 56 #include <linux/netdevice.h> 57 #include <linux/in_route.h> 58 #include <linux/route.h> 59 #include <linux/skbuff.h> 60 #include <linux/igmp.h> 61 #include <net/net_namespace.h> 62 #include <net/dst.h> 63 #include <net/sock.h> 64 #include <linux/ip.h> 65 #include <linux/net.h> 66 #include <net/ip.h> 67 #include <net/icmp.h> 68 #include <net/udp.h> 69 #include <net/raw.h> 70 #include <net/snmp.h> 71 #include <net/tcp_states.h> 72 #include <net/inet_common.h> 73 #include <net/checksum.h> 74 #include <net/xfrm.h> 75 #include <linux/rtnetlink.h> 76 #include <linux/proc_fs.h> 77 #include <linux/seq_file.h> 78 #include <linux/netfilter.h> 79 #include <linux/netfilter_ipv4.h> 80 #include <linux/compat.h> 81 #include <linux/uio.h> 82 83 struct raw_frag_vec { 84 struct msghdr *msg; 85 union { 86 struct icmphdr icmph; 87 char c[1]; 88 } hdr; 89 int hlen; 90 }; 91 92 static struct raw_hashinfo raw_v4_hashinfo = { 93 .lock = __RW_LOCK_UNLOCKED(raw_v4_hashinfo.lock), 94 }; 95 96 int raw_hash_sk(struct sock *sk) 97 { 98 struct raw_hashinfo *h = sk->sk_prot->h.raw_hash; 99 struct hlist_head *head; 100 101 head = &h->ht[inet_sk(sk)->inet_num & (RAW_HTABLE_SIZE - 1)]; 102 103 write_lock_bh(&h->lock); 104 sk_add_node(sk, head); 105 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1); 106 write_unlock_bh(&h->lock); 107 108 return 0; 109 } 110 EXPORT_SYMBOL_GPL(raw_hash_sk); 111 112 void raw_unhash_sk(struct sock *sk) 113 { 114 struct raw_hashinfo *h = sk->sk_prot->h.raw_hash; 115 116 write_lock_bh(&h->lock); 117 if (sk_del_node_init(sk)) 118 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1); 119 write_unlock_bh(&h->lock); 120 } 121 EXPORT_SYMBOL_GPL(raw_unhash_sk); 122 123 static struct sock *__raw_v4_lookup(struct net *net, struct sock *sk, 124 unsigned short num, __be32 raddr, __be32 laddr, int dif) 125 { 126 sk_for_each_from(sk) { 127 struct inet_sock *inet = inet_sk(sk); 128 129 if (net_eq(sock_net(sk), net) && inet->inet_num == num && 130 !(inet->inet_daddr && inet->inet_daddr != raddr) && 131 !(inet->inet_rcv_saddr && inet->inet_rcv_saddr != laddr) && 132 !(sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif)) 133 goto found; /* gotcha */ 134 } 135 sk = NULL; 136 found: 137 return sk; 138 } 139 140 /* 141 * 0 - deliver 142 * 1 - block 143 */ 144 static int icmp_filter(const struct sock *sk, const struct sk_buff *skb) 145 { 146 struct icmphdr _hdr; 147 const struct icmphdr *hdr; 148 149 hdr = skb_header_pointer(skb, skb_transport_offset(skb), 150 sizeof(_hdr), &_hdr); 151 if (!hdr) 152 return 1; 153 154 if (hdr->type < 32) { 155 __u32 data = raw_sk(sk)->filter.data; 156 157 return ((1U << hdr->type) & data) != 0; 158 } 159 160 /* Do not block unknown ICMP types */ 161 return 0; 162 } 163 164 /* IP input processing comes here for RAW socket delivery. 165 * Caller owns SKB, so we must make clones. 166 * 167 * RFC 1122: SHOULD pass TOS value up to the transport layer. 168 * -> It does. And not only TOS, but all IP header. 169 */ 170 static int raw_v4_input(struct sk_buff *skb, const struct iphdr *iph, int hash) 171 { 172 struct sock *sk; 173 struct hlist_head *head; 174 int delivered = 0; 175 struct net *net; 176 177 read_lock(&raw_v4_hashinfo.lock); 178 head = &raw_v4_hashinfo.ht[hash]; 179 if (hlist_empty(head)) 180 goto out; 181 182 net = dev_net(skb->dev); 183 sk = __raw_v4_lookup(net, __sk_head(head), iph->protocol, 184 iph->saddr, iph->daddr, 185 skb->dev->ifindex); 186 187 while (sk) { 188 delivered = 1; 189 if ((iph->protocol != IPPROTO_ICMP || !icmp_filter(sk, skb)) && 190 ip_mc_sf_allow(sk, iph->daddr, iph->saddr, 191 skb->dev->ifindex)) { 192 struct sk_buff *clone = skb_clone(skb, GFP_ATOMIC); 193 194 /* Not releasing hash table! */ 195 if (clone) 196 raw_rcv(sk, clone); 197 } 198 sk = __raw_v4_lookup(net, sk_next(sk), iph->protocol, 199 iph->saddr, iph->daddr, 200 skb->dev->ifindex); 201 } 202 out: 203 read_unlock(&raw_v4_hashinfo.lock); 204 return delivered; 205 } 206 207 int raw_local_deliver(struct sk_buff *skb, int protocol) 208 { 209 int hash; 210 struct sock *raw_sk; 211 212 hash = protocol & (RAW_HTABLE_SIZE - 1); 213 raw_sk = sk_head(&raw_v4_hashinfo.ht[hash]); 214 215 /* If there maybe a raw socket we must check - if not we 216 * don't care less 217 */ 218 if (raw_sk && !raw_v4_input(skb, ip_hdr(skb), hash)) 219 raw_sk = NULL; 220 221 return raw_sk != NULL; 222 223 } 224 225 static void raw_err(struct sock *sk, struct sk_buff *skb, u32 info) 226 { 227 struct inet_sock *inet = inet_sk(sk); 228 const int type = icmp_hdr(skb)->type; 229 const int code = icmp_hdr(skb)->code; 230 int err = 0; 231 int harderr = 0; 232 233 if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) 234 ipv4_sk_update_pmtu(skb, sk, info); 235 else if (type == ICMP_REDIRECT) { 236 ipv4_sk_redirect(skb, sk); 237 return; 238 } 239 240 /* Report error on raw socket, if: 241 1. User requested ip_recverr. 242 2. Socket is connected (otherwise the error indication 243 is useless without ip_recverr and error is hard. 244 */ 245 if (!inet->recverr && sk->sk_state != TCP_ESTABLISHED) 246 return; 247 248 switch (type) { 249 default: 250 case ICMP_TIME_EXCEEDED: 251 err = EHOSTUNREACH; 252 break; 253 case ICMP_SOURCE_QUENCH: 254 return; 255 case ICMP_PARAMETERPROB: 256 err = EPROTO; 257 harderr = 1; 258 break; 259 case ICMP_DEST_UNREACH: 260 err = EHOSTUNREACH; 261 if (code > NR_ICMP_UNREACH) 262 break; 263 err = icmp_err_convert[code].errno; 264 harderr = icmp_err_convert[code].fatal; 265 if (code == ICMP_FRAG_NEEDED) { 266 harderr = inet->pmtudisc != IP_PMTUDISC_DONT; 267 err = EMSGSIZE; 268 } 269 } 270 271 if (inet->recverr) { 272 const struct iphdr *iph = (const struct iphdr *)skb->data; 273 u8 *payload = skb->data + (iph->ihl << 2); 274 275 if (inet->hdrincl) 276 payload = skb->data; 277 ip_icmp_error(sk, skb, err, 0, info, payload); 278 } 279 280 if (inet->recverr || harderr) { 281 sk->sk_err = err; 282 sk->sk_error_report(sk); 283 } 284 } 285 286 void raw_icmp_error(struct sk_buff *skb, int protocol, u32 info) 287 { 288 int hash; 289 struct sock *raw_sk; 290 const struct iphdr *iph; 291 struct net *net; 292 293 hash = protocol & (RAW_HTABLE_SIZE - 1); 294 295 read_lock(&raw_v4_hashinfo.lock); 296 raw_sk = sk_head(&raw_v4_hashinfo.ht[hash]); 297 if (raw_sk) { 298 iph = (const struct iphdr *)skb->data; 299 net = dev_net(skb->dev); 300 301 while ((raw_sk = __raw_v4_lookup(net, raw_sk, protocol, 302 iph->daddr, iph->saddr, 303 skb->dev->ifindex)) != NULL) { 304 raw_err(raw_sk, skb, info); 305 raw_sk = sk_next(raw_sk); 306 iph = (const struct iphdr *)skb->data; 307 } 308 } 309 read_unlock(&raw_v4_hashinfo.lock); 310 } 311 312 static int raw_rcv_skb(struct sock *sk, struct sk_buff *skb) 313 { 314 /* Charge it to the socket. */ 315 316 ipv4_pktinfo_prepare(sk, skb); 317 if (sock_queue_rcv_skb(sk, skb) < 0) { 318 kfree_skb(skb); 319 return NET_RX_DROP; 320 } 321 322 return NET_RX_SUCCESS; 323 } 324 325 int raw_rcv(struct sock *sk, struct sk_buff *skb) 326 { 327 if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) { 328 atomic_inc(&sk->sk_drops); 329 kfree_skb(skb); 330 return NET_RX_DROP; 331 } 332 nf_reset(skb); 333 334 skb_push(skb, skb->data - skb_network_header(skb)); 335 336 raw_rcv_skb(sk, skb); 337 return 0; 338 } 339 340 static int raw_send_hdrinc(struct sock *sk, struct flowi4 *fl4, 341 struct msghdr *msg, size_t length, 342 struct rtable **rtp, 343 unsigned int flags) 344 { 345 struct inet_sock *inet = inet_sk(sk); 346 struct net *net = sock_net(sk); 347 struct iphdr *iph; 348 struct sk_buff *skb; 349 unsigned int iphlen; 350 int err; 351 struct rtable *rt = *rtp; 352 int hlen, tlen; 353 354 if (length > rt->dst.dev->mtu) { 355 ip_local_error(sk, EMSGSIZE, fl4->daddr, inet->inet_dport, 356 rt->dst.dev->mtu); 357 return -EMSGSIZE; 358 } 359 if (flags&MSG_PROBE) 360 goto out; 361 362 hlen = LL_RESERVED_SPACE(rt->dst.dev); 363 tlen = rt->dst.dev->needed_tailroom; 364 skb = sock_alloc_send_skb(sk, 365 length + hlen + tlen + 15, 366 flags & MSG_DONTWAIT, &err); 367 if (!skb) 368 goto error; 369 skb_reserve(skb, hlen); 370 371 skb->priority = sk->sk_priority; 372 skb->mark = sk->sk_mark; 373 skb_dst_set(skb, &rt->dst); 374 *rtp = NULL; 375 376 skb_reset_network_header(skb); 377 iph = ip_hdr(skb); 378 skb_put(skb, length); 379 380 skb->ip_summed = CHECKSUM_NONE; 381 382 sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags); 383 384 skb->transport_header = skb->network_header; 385 err = -EFAULT; 386 if (memcpy_from_msg(iph, msg, length)) 387 goto error_free; 388 389 iphlen = iph->ihl * 4; 390 391 /* 392 * We don't want to modify the ip header, but we do need to 393 * be sure that it won't cause problems later along the network 394 * stack. Specifically we want to make sure that iph->ihl is a 395 * sane value. If ihl points beyond the length of the buffer passed 396 * in, reject the frame as invalid 397 */ 398 err = -EINVAL; 399 if (iphlen > length) 400 goto error_free; 401 402 if (iphlen >= sizeof(*iph)) { 403 if (!iph->saddr) 404 iph->saddr = fl4->saddr; 405 iph->check = 0; 406 iph->tot_len = htons(length); 407 if (!iph->id) 408 ip_select_ident(net, skb, NULL); 409 410 iph->check = ip_fast_csum((unsigned char *)iph, iph->ihl); 411 skb->transport_header += iphlen; 412 if (iph->protocol == IPPROTO_ICMP && 413 length >= iphlen + sizeof(struct icmphdr)) 414 icmp_out_count(net, ((struct icmphdr *) 415 skb_transport_header(skb))->type); 416 } 417 418 err = NF_HOOK(NFPROTO_IPV4, NF_INET_LOCAL_OUT, 419 net, sk, skb, NULL, rt->dst.dev, 420 dst_output); 421 if (err > 0) 422 err = net_xmit_errno(err); 423 if (err) 424 goto error; 425 out: 426 return 0; 427 428 error_free: 429 kfree_skb(skb); 430 error: 431 IP_INC_STATS(net, IPSTATS_MIB_OUTDISCARDS); 432 if (err == -ENOBUFS && !inet->recverr) 433 err = 0; 434 return err; 435 } 436 437 static int raw_probe_proto_opt(struct raw_frag_vec *rfv, struct flowi4 *fl4) 438 { 439 int err; 440 441 if (fl4->flowi4_proto != IPPROTO_ICMP) 442 return 0; 443 444 /* We only need the first two bytes. */ 445 rfv->hlen = 2; 446 447 err = memcpy_from_msg(rfv->hdr.c, rfv->msg, rfv->hlen); 448 if (err) 449 return err; 450 451 fl4->fl4_icmp_type = rfv->hdr.icmph.type; 452 fl4->fl4_icmp_code = rfv->hdr.icmph.code; 453 454 return 0; 455 } 456 457 static int raw_getfrag(void *from, char *to, int offset, int len, int odd, 458 struct sk_buff *skb) 459 { 460 struct raw_frag_vec *rfv = from; 461 462 if (offset < rfv->hlen) { 463 int copy = min(rfv->hlen - offset, len); 464 465 if (skb->ip_summed == CHECKSUM_PARTIAL) 466 memcpy(to, rfv->hdr.c + offset, copy); 467 else 468 skb->csum = csum_block_add( 469 skb->csum, 470 csum_partial_copy_nocheck(rfv->hdr.c + offset, 471 to, copy, 0), 472 odd); 473 474 odd = 0; 475 offset += copy; 476 to += copy; 477 len -= copy; 478 479 if (!len) 480 return 0; 481 } 482 483 offset -= rfv->hlen; 484 485 return ip_generic_getfrag(rfv->msg, to, offset, len, odd, skb); 486 } 487 488 static int raw_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) 489 { 490 struct inet_sock *inet = inet_sk(sk); 491 struct net *net = sock_net(sk); 492 struct ipcm_cookie ipc; 493 struct rtable *rt = NULL; 494 struct flowi4 fl4; 495 int free = 0; 496 __be32 daddr; 497 __be32 saddr; 498 u8 tos; 499 int err; 500 struct ip_options_data opt_copy; 501 struct raw_frag_vec rfv; 502 503 err = -EMSGSIZE; 504 if (len > 0xFFFF) 505 goto out; 506 507 /* 508 * Check the flags. 509 */ 510 511 err = -EOPNOTSUPP; 512 if (msg->msg_flags & MSG_OOB) /* Mirror BSD error message */ 513 goto out; /* compatibility */ 514 515 /* 516 * Get and verify the address. 517 */ 518 519 if (msg->msg_namelen) { 520 DECLARE_SOCKADDR(struct sockaddr_in *, usin, msg->msg_name); 521 err = -EINVAL; 522 if (msg->msg_namelen < sizeof(*usin)) 523 goto out; 524 if (usin->sin_family != AF_INET) { 525 pr_info_once("%s: %s forgot to set AF_INET. Fix it!\n", 526 __func__, current->comm); 527 err = -EAFNOSUPPORT; 528 if (usin->sin_family) 529 goto out; 530 } 531 daddr = usin->sin_addr.s_addr; 532 /* ANK: I did not forget to get protocol from port field. 533 * I just do not know, who uses this weirdness. 534 * IP_HDRINCL is much more convenient. 535 */ 536 } else { 537 err = -EDESTADDRREQ; 538 if (sk->sk_state != TCP_ESTABLISHED) 539 goto out; 540 daddr = inet->inet_daddr; 541 } 542 543 ipc.addr = inet->inet_saddr; 544 ipc.opt = NULL; 545 ipc.tx_flags = 0; 546 ipc.ttl = 0; 547 ipc.tos = -1; 548 ipc.oif = sk->sk_bound_dev_if; 549 550 if (msg->msg_controllen) { 551 err = ip_cmsg_send(net, msg, &ipc, false); 552 if (unlikely(err)) { 553 kfree(ipc.opt); 554 goto out; 555 } 556 if (ipc.opt) 557 free = 1; 558 } 559 560 saddr = ipc.addr; 561 ipc.addr = daddr; 562 563 if (!ipc.opt) { 564 struct ip_options_rcu *inet_opt; 565 566 rcu_read_lock(); 567 inet_opt = rcu_dereference(inet->inet_opt); 568 if (inet_opt) { 569 memcpy(&opt_copy, inet_opt, 570 sizeof(*inet_opt) + inet_opt->opt.optlen); 571 ipc.opt = &opt_copy.opt; 572 } 573 rcu_read_unlock(); 574 } 575 576 if (ipc.opt) { 577 err = -EINVAL; 578 /* Linux does not mangle headers on raw sockets, 579 * so that IP options + IP_HDRINCL is non-sense. 580 */ 581 if (inet->hdrincl) 582 goto done; 583 if (ipc.opt->opt.srr) { 584 if (!daddr) 585 goto done; 586 daddr = ipc.opt->opt.faddr; 587 } 588 } 589 tos = get_rtconn_flags(&ipc, sk); 590 if (msg->msg_flags & MSG_DONTROUTE) 591 tos |= RTO_ONLINK; 592 593 if (ipv4_is_multicast(daddr)) { 594 if (!ipc.oif) 595 ipc.oif = inet->mc_index; 596 if (!saddr) 597 saddr = inet->mc_addr; 598 } else if (!ipc.oif) 599 ipc.oif = inet->uc_index; 600 601 flowi4_init_output(&fl4, ipc.oif, sk->sk_mark, tos, 602 RT_SCOPE_UNIVERSE, 603 inet->hdrincl ? IPPROTO_RAW : sk->sk_protocol, 604 inet_sk_flowi_flags(sk) | 605 (inet->hdrincl ? FLOWI_FLAG_KNOWN_NH : 0), 606 daddr, saddr, 0, 0); 607 608 if (!saddr && ipc.oif) { 609 err = l3mdev_get_saddr(net, ipc.oif, &fl4); 610 if (err < 0) 611 goto done; 612 } 613 614 if (!inet->hdrincl) { 615 rfv.msg = msg; 616 rfv.hlen = 0; 617 618 err = raw_probe_proto_opt(&rfv, &fl4); 619 if (err) 620 goto done; 621 } 622 623 security_sk_classify_flow(sk, flowi4_to_flowi(&fl4)); 624 rt = ip_route_output_flow(net, &fl4, sk); 625 if (IS_ERR(rt)) { 626 err = PTR_ERR(rt); 627 rt = NULL; 628 goto done; 629 } 630 631 err = -EACCES; 632 if (rt->rt_flags & RTCF_BROADCAST && !sock_flag(sk, SOCK_BROADCAST)) 633 goto done; 634 635 if (msg->msg_flags & MSG_CONFIRM) 636 goto do_confirm; 637 back_from_confirm: 638 639 if (inet->hdrincl) 640 err = raw_send_hdrinc(sk, &fl4, msg, len, 641 &rt, msg->msg_flags); 642 643 else { 644 sock_tx_timestamp(sk, &ipc.tx_flags); 645 646 if (!ipc.addr) 647 ipc.addr = fl4.daddr; 648 lock_sock(sk); 649 err = ip_append_data(sk, &fl4, raw_getfrag, 650 &rfv, len, 0, 651 &ipc, &rt, msg->msg_flags); 652 if (err) 653 ip_flush_pending_frames(sk); 654 else if (!(msg->msg_flags & MSG_MORE)) { 655 err = ip_push_pending_frames(sk, &fl4); 656 if (err == -ENOBUFS && !inet->recverr) 657 err = 0; 658 } 659 release_sock(sk); 660 } 661 done: 662 if (free) 663 kfree(ipc.opt); 664 ip_rt_put(rt); 665 666 out: 667 if (err < 0) 668 return err; 669 return len; 670 671 do_confirm: 672 dst_confirm(&rt->dst); 673 if (!(msg->msg_flags & MSG_PROBE) || len) 674 goto back_from_confirm; 675 err = 0; 676 goto done; 677 } 678 679 static void raw_close(struct sock *sk, long timeout) 680 { 681 /* 682 * Raw sockets may have direct kernel references. Kill them. 683 */ 684 ip_ra_control(sk, 0, NULL); 685 686 sk_common_release(sk); 687 } 688 689 static void raw_destroy(struct sock *sk) 690 { 691 lock_sock(sk); 692 ip_flush_pending_frames(sk); 693 release_sock(sk); 694 } 695 696 /* This gets rid of all the nasties in af_inet. -DaveM */ 697 static int raw_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len) 698 { 699 struct inet_sock *inet = inet_sk(sk); 700 struct sockaddr_in *addr = (struct sockaddr_in *) uaddr; 701 int ret = -EINVAL; 702 int chk_addr_ret; 703 704 if (sk->sk_state != TCP_CLOSE || addr_len < sizeof(struct sockaddr_in)) 705 goto out; 706 chk_addr_ret = inet_addr_type(sock_net(sk), addr->sin_addr.s_addr); 707 ret = -EADDRNOTAVAIL; 708 if (addr->sin_addr.s_addr && chk_addr_ret != RTN_LOCAL && 709 chk_addr_ret != RTN_MULTICAST && chk_addr_ret != RTN_BROADCAST) 710 goto out; 711 inet->inet_rcv_saddr = inet->inet_saddr = addr->sin_addr.s_addr; 712 if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST) 713 inet->inet_saddr = 0; /* Use device */ 714 sk_dst_reset(sk); 715 ret = 0; 716 out: return ret; 717 } 718 719 /* 720 * This should be easy, if there is something there 721 * we return it, otherwise we block. 722 */ 723 724 static int raw_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, 725 int noblock, int flags, int *addr_len) 726 { 727 struct inet_sock *inet = inet_sk(sk); 728 size_t copied = 0; 729 int err = -EOPNOTSUPP; 730 DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name); 731 struct sk_buff *skb; 732 733 if (flags & MSG_OOB) 734 goto out; 735 736 if (flags & MSG_ERRQUEUE) { 737 err = ip_recv_error(sk, msg, len, addr_len); 738 goto out; 739 } 740 741 skb = skb_recv_datagram(sk, flags, noblock, &err); 742 if (!skb) 743 goto out; 744 745 copied = skb->len; 746 if (len < copied) { 747 msg->msg_flags |= MSG_TRUNC; 748 copied = len; 749 } 750 751 err = skb_copy_datagram_msg(skb, 0, msg, copied); 752 if (err) 753 goto done; 754 755 sock_recv_ts_and_drops(msg, sk, skb); 756 757 /* Copy the address. */ 758 if (sin) { 759 sin->sin_family = AF_INET; 760 sin->sin_addr.s_addr = ip_hdr(skb)->saddr; 761 sin->sin_port = 0; 762 memset(&sin->sin_zero, 0, sizeof(sin->sin_zero)); 763 *addr_len = sizeof(*sin); 764 } 765 if (inet->cmsg_flags) 766 ip_cmsg_recv(msg, skb); 767 if (flags & MSG_TRUNC) 768 copied = skb->len; 769 done: 770 skb_free_datagram(sk, skb); 771 out: 772 if (err) 773 return err; 774 return copied; 775 } 776 777 static int raw_init(struct sock *sk) 778 { 779 struct raw_sock *rp = raw_sk(sk); 780 781 if (inet_sk(sk)->inet_num == IPPROTO_ICMP) 782 memset(&rp->filter, 0, sizeof(rp->filter)); 783 return 0; 784 } 785 786 static int raw_seticmpfilter(struct sock *sk, char __user *optval, int optlen) 787 { 788 if (optlen > sizeof(struct icmp_filter)) 789 optlen = sizeof(struct icmp_filter); 790 if (copy_from_user(&raw_sk(sk)->filter, optval, optlen)) 791 return -EFAULT; 792 return 0; 793 } 794 795 static int raw_geticmpfilter(struct sock *sk, char __user *optval, int __user *optlen) 796 { 797 int len, ret = -EFAULT; 798 799 if (get_user(len, optlen)) 800 goto out; 801 ret = -EINVAL; 802 if (len < 0) 803 goto out; 804 if (len > sizeof(struct icmp_filter)) 805 len = sizeof(struct icmp_filter); 806 ret = -EFAULT; 807 if (put_user(len, optlen) || 808 copy_to_user(optval, &raw_sk(sk)->filter, len)) 809 goto out; 810 ret = 0; 811 out: return ret; 812 } 813 814 static int do_raw_setsockopt(struct sock *sk, int level, int optname, 815 char __user *optval, unsigned int optlen) 816 { 817 if (optname == ICMP_FILTER) { 818 if (inet_sk(sk)->inet_num != IPPROTO_ICMP) 819 return -EOPNOTSUPP; 820 else 821 return raw_seticmpfilter(sk, optval, optlen); 822 } 823 return -ENOPROTOOPT; 824 } 825 826 static int raw_setsockopt(struct sock *sk, int level, int optname, 827 char __user *optval, unsigned int optlen) 828 { 829 if (level != SOL_RAW) 830 return ip_setsockopt(sk, level, optname, optval, optlen); 831 return do_raw_setsockopt(sk, level, optname, optval, optlen); 832 } 833 834 #ifdef CONFIG_COMPAT 835 static int compat_raw_setsockopt(struct sock *sk, int level, int optname, 836 char __user *optval, unsigned int optlen) 837 { 838 if (level != SOL_RAW) 839 return compat_ip_setsockopt(sk, level, optname, optval, optlen); 840 return do_raw_setsockopt(sk, level, optname, optval, optlen); 841 } 842 #endif 843 844 static int do_raw_getsockopt(struct sock *sk, int level, int optname, 845 char __user *optval, int __user *optlen) 846 { 847 if (optname == ICMP_FILTER) { 848 if (inet_sk(sk)->inet_num != IPPROTO_ICMP) 849 return -EOPNOTSUPP; 850 else 851 return raw_geticmpfilter(sk, optval, optlen); 852 } 853 return -ENOPROTOOPT; 854 } 855 856 static int raw_getsockopt(struct sock *sk, int level, int optname, 857 char __user *optval, int __user *optlen) 858 { 859 if (level != SOL_RAW) 860 return ip_getsockopt(sk, level, optname, optval, optlen); 861 return do_raw_getsockopt(sk, level, optname, optval, optlen); 862 } 863 864 #ifdef CONFIG_COMPAT 865 static int compat_raw_getsockopt(struct sock *sk, int level, int optname, 866 char __user *optval, int __user *optlen) 867 { 868 if (level != SOL_RAW) 869 return compat_ip_getsockopt(sk, level, optname, optval, optlen); 870 return do_raw_getsockopt(sk, level, optname, optval, optlen); 871 } 872 #endif 873 874 static int raw_ioctl(struct sock *sk, int cmd, unsigned long arg) 875 { 876 switch (cmd) { 877 case SIOCOUTQ: { 878 int amount = sk_wmem_alloc_get(sk); 879 880 return put_user(amount, (int __user *)arg); 881 } 882 case SIOCINQ: { 883 struct sk_buff *skb; 884 int amount = 0; 885 886 spin_lock_bh(&sk->sk_receive_queue.lock); 887 skb = skb_peek(&sk->sk_receive_queue); 888 if (skb) 889 amount = skb->len; 890 spin_unlock_bh(&sk->sk_receive_queue.lock); 891 return put_user(amount, (int __user *)arg); 892 } 893 894 default: 895 #ifdef CONFIG_IP_MROUTE 896 return ipmr_ioctl(sk, cmd, (void __user *)arg); 897 #else 898 return -ENOIOCTLCMD; 899 #endif 900 } 901 } 902 903 #ifdef CONFIG_COMPAT 904 static int compat_raw_ioctl(struct sock *sk, unsigned int cmd, unsigned long arg) 905 { 906 switch (cmd) { 907 case SIOCOUTQ: 908 case SIOCINQ: 909 return -ENOIOCTLCMD; 910 default: 911 #ifdef CONFIG_IP_MROUTE 912 return ipmr_compat_ioctl(sk, cmd, compat_ptr(arg)); 913 #else 914 return -ENOIOCTLCMD; 915 #endif 916 } 917 } 918 #endif 919 920 struct proto raw_prot = { 921 .name = "RAW", 922 .owner = THIS_MODULE, 923 .close = raw_close, 924 .destroy = raw_destroy, 925 .connect = ip4_datagram_connect, 926 .disconnect = udp_disconnect, 927 .ioctl = raw_ioctl, 928 .init = raw_init, 929 .setsockopt = raw_setsockopt, 930 .getsockopt = raw_getsockopt, 931 .sendmsg = raw_sendmsg, 932 .recvmsg = raw_recvmsg, 933 .bind = raw_bind, 934 .backlog_rcv = raw_rcv_skb, 935 .release_cb = ip4_datagram_release_cb, 936 .hash = raw_hash_sk, 937 .unhash = raw_unhash_sk, 938 .obj_size = sizeof(struct raw_sock), 939 .h.raw_hash = &raw_v4_hashinfo, 940 #ifdef CONFIG_COMPAT 941 .compat_setsockopt = compat_raw_setsockopt, 942 .compat_getsockopt = compat_raw_getsockopt, 943 .compat_ioctl = compat_raw_ioctl, 944 #endif 945 }; 946 947 #ifdef CONFIG_PROC_FS 948 static struct sock *raw_get_first(struct seq_file *seq) 949 { 950 struct sock *sk; 951 struct raw_iter_state *state = raw_seq_private(seq); 952 953 for (state->bucket = 0; state->bucket < RAW_HTABLE_SIZE; 954 ++state->bucket) { 955 sk_for_each(sk, &state->h->ht[state->bucket]) 956 if (sock_net(sk) == seq_file_net(seq)) 957 goto found; 958 } 959 sk = NULL; 960 found: 961 return sk; 962 } 963 964 static struct sock *raw_get_next(struct seq_file *seq, struct sock *sk) 965 { 966 struct raw_iter_state *state = raw_seq_private(seq); 967 968 do { 969 sk = sk_next(sk); 970 try_again: 971 ; 972 } while (sk && sock_net(sk) != seq_file_net(seq)); 973 974 if (!sk && ++state->bucket < RAW_HTABLE_SIZE) { 975 sk = sk_head(&state->h->ht[state->bucket]); 976 goto try_again; 977 } 978 return sk; 979 } 980 981 static struct sock *raw_get_idx(struct seq_file *seq, loff_t pos) 982 { 983 struct sock *sk = raw_get_first(seq); 984 985 if (sk) 986 while (pos && (sk = raw_get_next(seq, sk)) != NULL) 987 --pos; 988 return pos ? NULL : sk; 989 } 990 991 void *raw_seq_start(struct seq_file *seq, loff_t *pos) 992 { 993 struct raw_iter_state *state = raw_seq_private(seq); 994 995 read_lock(&state->h->lock); 996 return *pos ? raw_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; 997 } 998 EXPORT_SYMBOL_GPL(raw_seq_start); 999 1000 void *raw_seq_next(struct seq_file *seq, void *v, loff_t *pos) 1001 { 1002 struct sock *sk; 1003 1004 if (v == SEQ_START_TOKEN) 1005 sk = raw_get_first(seq); 1006 else 1007 sk = raw_get_next(seq, v); 1008 ++*pos; 1009 return sk; 1010 } 1011 EXPORT_SYMBOL_GPL(raw_seq_next); 1012 1013 void raw_seq_stop(struct seq_file *seq, void *v) 1014 { 1015 struct raw_iter_state *state = raw_seq_private(seq); 1016 1017 read_unlock(&state->h->lock); 1018 } 1019 EXPORT_SYMBOL_GPL(raw_seq_stop); 1020 1021 static void raw_sock_seq_show(struct seq_file *seq, struct sock *sp, int i) 1022 { 1023 struct inet_sock *inet = inet_sk(sp); 1024 __be32 dest = inet->inet_daddr, 1025 src = inet->inet_rcv_saddr; 1026 __u16 destp = 0, 1027 srcp = inet->inet_num; 1028 1029 seq_printf(seq, "%4d: %08X:%04X %08X:%04X" 1030 " %02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %d\n", 1031 i, src, srcp, dest, destp, sp->sk_state, 1032 sk_wmem_alloc_get(sp), 1033 sk_rmem_alloc_get(sp), 1034 0, 0L, 0, 1035 from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)), 1036 0, sock_i_ino(sp), 1037 atomic_read(&sp->sk_refcnt), sp, atomic_read(&sp->sk_drops)); 1038 } 1039 1040 static int raw_seq_show(struct seq_file *seq, void *v) 1041 { 1042 if (v == SEQ_START_TOKEN) 1043 seq_printf(seq, " sl local_address rem_address st tx_queue " 1044 "rx_queue tr tm->when retrnsmt uid timeout " 1045 "inode ref pointer drops\n"); 1046 else 1047 raw_sock_seq_show(seq, v, raw_seq_private(seq)->bucket); 1048 return 0; 1049 } 1050 1051 static const struct seq_operations raw_seq_ops = { 1052 .start = raw_seq_start, 1053 .next = raw_seq_next, 1054 .stop = raw_seq_stop, 1055 .show = raw_seq_show, 1056 }; 1057 1058 int raw_seq_open(struct inode *ino, struct file *file, 1059 struct raw_hashinfo *h, const struct seq_operations *ops) 1060 { 1061 int err; 1062 struct raw_iter_state *i; 1063 1064 err = seq_open_net(ino, file, ops, sizeof(struct raw_iter_state)); 1065 if (err < 0) 1066 return err; 1067 1068 i = raw_seq_private((struct seq_file *)file->private_data); 1069 i->h = h; 1070 return 0; 1071 } 1072 EXPORT_SYMBOL_GPL(raw_seq_open); 1073 1074 static int raw_v4_seq_open(struct inode *inode, struct file *file) 1075 { 1076 return raw_seq_open(inode, file, &raw_v4_hashinfo, &raw_seq_ops); 1077 } 1078 1079 static const struct file_operations raw_seq_fops = { 1080 .owner = THIS_MODULE, 1081 .open = raw_v4_seq_open, 1082 .read = seq_read, 1083 .llseek = seq_lseek, 1084 .release = seq_release_net, 1085 }; 1086 1087 static __net_init int raw_init_net(struct net *net) 1088 { 1089 if (!proc_create("raw", S_IRUGO, net->proc_net, &raw_seq_fops)) 1090 return -ENOMEM; 1091 1092 return 0; 1093 } 1094 1095 static __net_exit void raw_exit_net(struct net *net) 1096 { 1097 remove_proc_entry("raw", net->proc_net); 1098 } 1099 1100 static __net_initdata struct pernet_operations raw_net_ops = { 1101 .init = raw_init_net, 1102 .exit = raw_exit_net, 1103 }; 1104 1105 int __init raw_proc_init(void) 1106 { 1107 return register_pernet_subsys(&raw_net_ops); 1108 } 1109 1110 void __init raw_proc_exit(void) 1111 { 1112 unregister_pernet_subsys(&raw_net_ops); 1113 } 1114 #endif /* CONFIG_PROC_FS */ 1115