ping.c revision bb0cd2fb539c4e454ed32e32194acc03b75753f3
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 * "Ping" sockets 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 * Based on ipv4/udp.c code. 14 * 15 * Authors: Vasiliy Kulikov / Openwall (for Linux 2.6), 16 * Pavel Kankovsky (for Linux 2.4.32) 17 * 18 * Pavel gave all rights to bugs to Vasiliy, 19 * none of the bugs are Pavel's now. 20 * 21 */ 22 23#include <asm/system.h> 24#include <linux/uaccess.h> 25#include <linux/types.h> 26#include <linux/fcntl.h> 27#include <linux/socket.h> 28#include <linux/sockios.h> 29#include <linux/in.h> 30#include <linux/errno.h> 31#include <linux/timer.h> 32#include <linux/mm.h> 33#include <linux/inet.h> 34#include <linux/netdevice.h> 35#include <net/snmp.h> 36#include <net/ip.h> 37#include <net/ipv6.h> 38#include <net/icmp.h> 39#include <net/protocol.h> 40#include <linux/skbuff.h> 41#include <linux/proc_fs.h> 42#include <net/sock.h> 43#include <net/ping.h> 44#include <net/icmp.h> 45#include <net/udp.h> 46#include <net/route.h> 47#include <net/inet_common.h> 48#include <net/checksum.h> 49 50 51static struct ping_table ping_table; 52 53static u16 ping_port_rover; 54 55static inline int ping_hashfn(struct net *net, unsigned num, unsigned mask) 56{ 57 int res = (num + net_hash_mix(net)) & mask; 58 pr_debug("hash(%d) = %d\n", num, res); 59 return res; 60} 61 62static inline struct hlist_nulls_head *ping_hashslot(struct ping_table *table, 63 struct net *net, unsigned num) 64{ 65 return &table->hash[ping_hashfn(net, num, PING_HTABLE_MASK)]; 66} 67 68static int ping_v4_get_port(struct sock *sk, unsigned short ident) 69{ 70 struct hlist_nulls_node *node; 71 struct hlist_nulls_head *hlist; 72 struct inet_sock *isk, *isk2; 73 struct sock *sk2 = NULL; 74 75 isk = inet_sk(sk); 76 write_lock_bh(&ping_table.lock); 77 if (ident == 0) { 78 u32 i; 79 u16 result = ping_port_rover + 1; 80 81 for (i = 0; i < (1L << 16); i++, result++) { 82 if (!result) 83 result++; /* avoid zero */ 84 hlist = ping_hashslot(&ping_table, sock_net(sk), 85 result); 86 ping_portaddr_for_each_entry(sk2, node, hlist) { 87 isk2 = inet_sk(sk2); 88 89 if (isk2->inet_num == result) 90 goto next_port; 91 } 92 93 /* found */ 94 ping_port_rover = ident = result; 95 break; 96next_port: 97 ; 98 } 99 if (i >= (1L << 16)) 100 goto fail; 101 } else { 102 hlist = ping_hashslot(&ping_table, sock_net(sk), ident); 103 ping_portaddr_for_each_entry(sk2, node, hlist) { 104 isk2 = inet_sk(sk2); 105 106 if ((isk2->inet_num == ident) && 107 (sk2 != sk) && 108 (!sk2->sk_reuse || !sk->sk_reuse)) 109 goto fail; 110 } 111 } 112 113 pr_debug("found port/ident = %d\n", ident); 114 isk->inet_num = ident; 115 if (sk_unhashed(sk)) { 116 pr_debug("was not hashed\n"); 117 sock_hold(sk); 118 hlist_nulls_add_head(&sk->sk_nulls_node, hlist); 119 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1); 120 } 121 write_unlock_bh(&ping_table.lock); 122 return 0; 123 124fail: 125 write_unlock_bh(&ping_table.lock); 126 return 1; 127} 128 129static void ping_v4_hash(struct sock *sk) 130{ 131 pr_debug("ping_v4_hash(sk->port=%u)\n", inet_sk(sk)->inet_num); 132 BUG(); /* "Please do not press this button again." */ 133} 134 135static void ping_v4_unhash(struct sock *sk) 136{ 137 struct inet_sock *isk = inet_sk(sk); 138 pr_debug("ping_v4_unhash(isk=%p,isk->num=%u)\n", isk, isk->inet_num); 139 if (sk_hashed(sk)) { 140 struct hlist_nulls_head *hslot; 141 142 hslot = ping_hashslot(&ping_table, sock_net(sk), isk->inet_num); 143 write_lock_bh(&ping_table.lock); 144 hlist_nulls_del(&sk->sk_nulls_node); 145 sock_put(sk); 146 isk->inet_num = isk->inet_sport = 0; 147 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1); 148 write_unlock_bh(&ping_table.lock); 149 } 150} 151 152static struct sock *ping_v4_lookup(struct net *net, u32 saddr, u32 daddr, 153 u16 ident, int dif) 154{ 155 struct hlist_nulls_head *hslot = ping_hashslot(&ping_table, net, ident); 156 struct sock *sk = NULL; 157 struct inet_sock *isk; 158 struct hlist_nulls_node *hnode; 159 160 pr_debug("try to find: num = %d, daddr = %ld, dif = %d\n", 161 (int)ident, (unsigned long)daddr, dif); 162 read_lock_bh(&ping_table.lock); 163 164 ping_portaddr_for_each_entry(sk, hnode, hslot) { 165 isk = inet_sk(sk); 166 167 pr_debug("found: %p: num = %d, daddr = %ld, dif = %d\n", sk, 168 (int)isk->inet_num, (unsigned long)isk->inet_rcv_saddr, 169 sk->sk_bound_dev_if); 170 171 pr_debug("iterate\n"); 172 if (isk->inet_num != ident) 173 continue; 174 if (isk->inet_rcv_saddr && isk->inet_rcv_saddr != daddr) 175 continue; 176 if (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif) 177 continue; 178 179 sock_hold(sk); 180 goto exit; 181 } 182 183 sk = NULL; 184exit: 185 read_unlock_bh(&ping_table.lock); 186 187 return sk; 188} 189 190static void inet_get_ping_group_range_net(struct net *net, gid_t *low, gid_t *high) 191{ 192 gid_t *data = net->ipv4.sysctl_ping_group_range; 193 unsigned seq; 194 do { 195 seq = read_seqbegin(&sysctl_local_ports.lock); 196 197 *low = data[0]; 198 *high = data[1]; 199 } while (read_seqretry(&sysctl_local_ports.lock, seq)); 200} 201 202 203static int ping_init_sock(struct sock *sk) 204{ 205 struct net *net = sock_net(sk); 206 gid_t group = current_egid(); 207 gid_t range[2]; 208 struct group_info *group_info = get_current_groups(); 209 int i, j, count = group_info->ngroups; 210 211 inet_get_ping_group_range_net(net, range, range+1); 212 if (range[0] <= group && group <= range[1]) 213 return 0; 214 215 for (i = 0; i < group_info->nblocks; i++) { 216 int cp_count = min_t(int, NGROUPS_PER_BLOCK, count); 217 218 for (j = 0; j < cp_count; j++) { 219 group = group_info->blocks[i][j]; 220 if (range[0] <= group && group <= range[1]) 221 return 0; 222 } 223 224 count -= cp_count; 225 } 226 227 return -EACCES; 228} 229 230static void ping_close(struct sock *sk, long timeout) 231{ 232 pr_debug("ping_close(sk=%p,sk->num=%u)\n", 233 inet_sk(sk), inet_sk(sk)->inet_num); 234 pr_debug("isk->refcnt = %d\n", sk->sk_refcnt.counter); 235 236 sk_common_release(sk); 237} 238 239/* 240 * We need our own bind because there are no privileged id's == local ports. 241 * Moreover, we don't allow binding to multi- and broadcast addresses. 242 */ 243 244static int ping_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len) 245{ 246 struct sockaddr_in *addr = (struct sockaddr_in *)uaddr; 247 struct inet_sock *isk = inet_sk(sk); 248 unsigned short snum; 249 int chk_addr_ret; 250 int err; 251 252 if (addr_len < sizeof(struct sockaddr_in)) 253 return -EINVAL; 254 255 pr_debug("ping_v4_bind(sk=%p,sa_addr=%08x,sa_port=%d)\n", 256 sk, addr->sin_addr.s_addr, ntohs(addr->sin_port)); 257 258 chk_addr_ret = inet_addr_type(sock_net(sk), addr->sin_addr.s_addr); 259 if (addr->sin_addr.s_addr == INADDR_ANY) 260 chk_addr_ret = RTN_LOCAL; 261 262 if ((sysctl_ip_nonlocal_bind == 0 && 263 isk->freebind == 0 && isk->transparent == 0 && 264 chk_addr_ret != RTN_LOCAL) || 265 chk_addr_ret == RTN_MULTICAST || 266 chk_addr_ret == RTN_BROADCAST) 267 return -EADDRNOTAVAIL; 268 269 lock_sock(sk); 270 271 err = -EINVAL; 272 if (isk->inet_num != 0) 273 goto out; 274 275 err = -EADDRINUSE; 276 isk->inet_rcv_saddr = isk->inet_saddr = addr->sin_addr.s_addr; 277 snum = ntohs(addr->sin_port); 278 if (ping_v4_get_port(sk, snum) != 0) { 279 isk->inet_saddr = isk->inet_rcv_saddr = 0; 280 goto out; 281 } 282 283 pr_debug("after bind(): num = %d, daddr = %ld, dif = %d\n", 284 (int)isk->inet_num, 285 (unsigned long) isk->inet_rcv_saddr, 286 (int)sk->sk_bound_dev_if); 287 288 err = 0; 289 if (isk->inet_rcv_saddr) 290 sk->sk_userlocks |= SOCK_BINDADDR_LOCK; 291 if (snum) 292 sk->sk_userlocks |= SOCK_BINDPORT_LOCK; 293 isk->inet_sport = htons(isk->inet_num); 294 isk->inet_daddr = 0; 295 isk->inet_dport = 0; 296 sk_dst_reset(sk); 297out: 298 release_sock(sk); 299 pr_debug("ping_v4_bind -> %d\n", err); 300 return err; 301} 302 303/* 304 * Is this a supported type of ICMP message? 305 */ 306 307static inline int ping_supported(int type, int code) 308{ 309 if (type == ICMP_ECHO && code == 0) 310 return 1; 311 return 0; 312} 313 314/* 315 * This routine is called by the ICMP module when it gets some 316 * sort of error condition. 317 */ 318 319static int ping_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); 320 321void ping_err(struct sk_buff *skb, u32 info) 322{ 323 struct iphdr *iph = (struct iphdr *)skb->data; 324 struct icmphdr *icmph = (struct icmphdr *)(skb->data+(iph->ihl<<2)); 325 struct inet_sock *inet_sock; 326 int type = icmph->type; 327 int code = icmph->code; 328 struct net *net = dev_net(skb->dev); 329 struct sock *sk; 330 int harderr; 331 int err; 332 333 /* We assume the packet has already been checked by icmp_unreach */ 334 335 if (!ping_supported(icmph->type, icmph->code)) 336 return; 337 338 pr_debug("ping_err(type=%04x,code=%04x,id=%04x,seq=%04x)\n", type, 339 code, ntohs(icmph->un.echo.id), ntohs(icmph->un.echo.sequence)); 340 341 sk = ping_v4_lookup(net, iph->daddr, iph->saddr, 342 ntohs(icmph->un.echo.id), skb->dev->ifindex); 343 if (sk == NULL) { 344 ICMP_INC_STATS_BH(net, ICMP_MIB_INERRORS); 345 pr_debug("no socket, dropping\n"); 346 return; /* No socket for error */ 347 } 348 pr_debug("err on socket %p\n", sk); 349 350 err = 0; 351 harderr = 0; 352 inet_sock = inet_sk(sk); 353 354 switch (type) { 355 default: 356 case ICMP_TIME_EXCEEDED: 357 err = EHOSTUNREACH; 358 break; 359 case ICMP_SOURCE_QUENCH: 360 /* This is not a real error but ping wants to see it. 361 * Report it with some fake errno. */ 362 err = EREMOTEIO; 363 break; 364 case ICMP_PARAMETERPROB: 365 err = EPROTO; 366 harderr = 1; 367 break; 368 case ICMP_DEST_UNREACH: 369 if (code == ICMP_FRAG_NEEDED) { /* Path MTU discovery */ 370 if (inet_sock->pmtudisc != IP_PMTUDISC_DONT) { 371 err = EMSGSIZE; 372 harderr = 1; 373 break; 374 } 375 goto out; 376 } 377 err = EHOSTUNREACH; 378 if (code <= NR_ICMP_UNREACH) { 379 harderr = icmp_err_convert[code].fatal; 380 err = icmp_err_convert[code].errno; 381 } 382 break; 383 case ICMP_REDIRECT: 384 /* See ICMP_SOURCE_QUENCH */ 385 err = EREMOTEIO; 386 break; 387 } 388 389 /* 390 * RFC1122: OK. Passes ICMP errors back to application, as per 391 * 4.1.3.3. 392 */ 393 if (!inet_sock->recverr) { 394 if (!harderr || sk->sk_state != TCP_ESTABLISHED) 395 goto out; 396 } else { 397 ip_icmp_error(sk, skb, err, 0 /* no remote port */, 398 info, (u8 *)icmph); 399 } 400 sk->sk_err = err; 401 sk->sk_error_report(sk); 402out: 403 sock_put(sk); 404} 405 406/* 407 * Copy and checksum an ICMP Echo packet from user space into a buffer. 408 */ 409 410struct pingfakehdr { 411 struct icmphdr icmph; 412 struct iovec *iov; 413 u32 wcheck; 414}; 415 416static int ping_getfrag(void *from, char * to, 417 int offset, int fraglen, int odd, struct sk_buff *skb) 418{ 419 struct pingfakehdr *pfh = (struct pingfakehdr *)from; 420 421 if (offset == 0) { 422 if (fraglen < sizeof(struct icmphdr)) 423 BUG(); 424 if (csum_partial_copy_fromiovecend(to + sizeof(struct icmphdr), 425 pfh->iov, 0, fraglen - sizeof(struct icmphdr), 426 &pfh->wcheck)) 427 return -EFAULT; 428 429 return 0; 430 } 431 if (offset < sizeof(struct icmphdr)) 432 BUG(); 433 if (csum_partial_copy_fromiovecend 434 (to, pfh->iov, offset - sizeof(struct icmphdr), 435 fraglen, &pfh->wcheck)) 436 return -EFAULT; 437 return 0; 438} 439 440static int ping_push_pending_frames(struct sock *sk, struct pingfakehdr *pfh, struct flowi4 *fl4) 441{ 442 struct sk_buff *skb = skb_peek(&sk->sk_write_queue); 443 444 pfh->wcheck = csum_partial((char *)&pfh->icmph, 445 sizeof(struct icmphdr), pfh->wcheck); 446 pfh->icmph.checksum = csum_fold(pfh->wcheck); 447 memcpy(icmp_hdr(skb), &pfh->icmph, sizeof(struct icmphdr)); 448 skb->ip_summed = CHECKSUM_NONE; 449 return ip_push_pending_frames(sk, fl4); 450} 451 452static int ping_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, 453 size_t len) 454{ 455 struct net *net = sock_net(sk); 456 struct flowi4 fl4; 457 struct inet_sock *inet = inet_sk(sk); 458 struct ipcm_cookie ipc; 459 struct icmphdr user_icmph; 460 struct pingfakehdr pfh; 461 struct rtable *rt = NULL; 462 struct ip_options_data opt_copy; 463 int free = 0; 464 u32 saddr, daddr, faddr; 465 u8 tos; 466 int err; 467 468 pr_debug("ping_sendmsg(sk=%p,sk->num=%u)\n", inet, inet->inet_num); 469 470 471 if (len > 0xFFFF) 472 return -EMSGSIZE; 473 474 /* 475 * Check the flags. 476 */ 477 478 /* Mirror BSD error message compatibility */ 479 if (msg->msg_flags & MSG_OOB) 480 return -EOPNOTSUPP; 481 482 /* 483 * Fetch the ICMP header provided by the userland. 484 * iovec is modified! 485 */ 486 487 if (memcpy_fromiovec((u8 *)&user_icmph, msg->msg_iov, 488 sizeof(struct icmphdr))) 489 return -EFAULT; 490 if (!ping_supported(user_icmph.type, user_icmph.code)) 491 return -EINVAL; 492 493 /* 494 * Get and verify the address. 495 */ 496 497 if (msg->msg_name) { 498 struct sockaddr_in *usin = (struct sockaddr_in *)msg->msg_name; 499 if (msg->msg_namelen < sizeof(*usin)) 500 return -EINVAL; 501 if (usin->sin_family != AF_INET) 502 return -EINVAL; 503 daddr = usin->sin_addr.s_addr; 504 /* no remote port */ 505 } else { 506 if (sk->sk_state != TCP_ESTABLISHED) 507 return -EDESTADDRREQ; 508 daddr = inet->inet_daddr; 509 /* no remote port */ 510 } 511 512 ipc.addr = inet->inet_saddr; 513 ipc.opt = NULL; 514 ipc.oif = sk->sk_bound_dev_if; 515 ipc.tx_flags = 0; 516 err = sock_tx_timestamp(sk, &ipc.tx_flags); 517 if (err) 518 return err; 519 520 if (msg->msg_controllen) { 521 err = ip_cmsg_send(sock_net(sk), msg, &ipc); 522 if (err) 523 return err; 524 if (ipc.opt) 525 free = 1; 526 } 527 if (!ipc.opt) { 528 struct ip_options_rcu *inet_opt; 529 530 rcu_read_lock(); 531 inet_opt = rcu_dereference(inet->inet_opt); 532 if (inet_opt) { 533 memcpy(&opt_copy, inet_opt, 534 sizeof(*inet_opt) + inet_opt->opt.optlen); 535 ipc.opt = &opt_copy.opt; 536 } 537 rcu_read_unlock(); 538 } 539 540 saddr = ipc.addr; 541 ipc.addr = faddr = daddr; 542 543 if (ipc.opt && ipc.opt->opt.srr) { 544 if (!daddr) 545 return -EINVAL; 546 faddr = ipc.opt->opt.faddr; 547 } 548 tos = RT_TOS(inet->tos); 549 if (sock_flag(sk, SOCK_LOCALROUTE) || 550 (msg->msg_flags & MSG_DONTROUTE) || 551 (ipc.opt && ipc.opt->opt.is_strictroute)) { 552 tos |= RTO_ONLINK; 553 } 554 555 if (ipv4_is_multicast(daddr)) { 556 if (!ipc.oif) 557 ipc.oif = inet->mc_index; 558 if (!saddr) 559 saddr = inet->mc_addr; 560 } 561 562 flowi4_init_output(&fl4, ipc.oif, sk->sk_mark, tos, 563 RT_SCOPE_UNIVERSE, sk->sk_protocol, 564 inet_sk_flowi_flags(sk), faddr, saddr, 0, 0); 565 566 security_sk_classify_flow(sk, flowi4_to_flowi(&fl4)); 567 rt = ip_route_output_flow(net, &fl4, sk); 568 if (IS_ERR(rt)) { 569 err = PTR_ERR(rt); 570 rt = NULL; 571 if (err == -ENETUNREACH) 572 IP_INC_STATS_BH(net, IPSTATS_MIB_OUTNOROUTES); 573 goto out; 574 } 575 576 err = -EACCES; 577 if ((rt->rt_flags & RTCF_BROADCAST) && 578 !sock_flag(sk, SOCK_BROADCAST)) 579 goto out; 580 581 if (msg->msg_flags & MSG_CONFIRM) 582 goto do_confirm; 583back_from_confirm: 584 585 if (!ipc.addr) 586 ipc.addr = fl4.daddr; 587 588 lock_sock(sk); 589 590 pfh.icmph.type = user_icmph.type; /* already checked */ 591 pfh.icmph.code = user_icmph.code; /* ditto */ 592 pfh.icmph.checksum = 0; 593 pfh.icmph.un.echo.id = inet->inet_sport; 594 pfh.icmph.un.echo.sequence = user_icmph.un.echo.sequence; 595 pfh.iov = msg->msg_iov; 596 pfh.wcheck = 0; 597 598 err = ip_append_data(sk, &fl4, ping_getfrag, &pfh, len, 599 0, &ipc, &rt, msg->msg_flags); 600 if (err) 601 ip_flush_pending_frames(sk); 602 else 603 err = ping_push_pending_frames(sk, &pfh, &fl4); 604 release_sock(sk); 605 606out: 607 ip_rt_put(rt); 608 if (free) 609 kfree(ipc.opt); 610 if (!err) { 611 icmp_out_count(sock_net(sk), user_icmph.type); 612 return len; 613 } 614 return err; 615 616do_confirm: 617 dst_confirm(&rt->dst); 618 if (!(msg->msg_flags & MSG_PROBE) || len) 619 goto back_from_confirm; 620 err = 0; 621 goto out; 622} 623 624static int ping_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, 625 size_t len, int noblock, int flags, int *addr_len) 626{ 627 struct inet_sock *isk = inet_sk(sk); 628 struct sockaddr_in *sin = (struct sockaddr_in *)msg->msg_name; 629 struct sk_buff *skb; 630 int copied, err; 631 632 pr_debug("ping_recvmsg(sk=%p,sk->num=%u)\n", isk, isk->inet_num); 633 634 if (flags & MSG_OOB) 635 goto out; 636 637 if (addr_len) 638 *addr_len = sizeof(*sin); 639 640 if (flags & MSG_ERRQUEUE) 641 return ip_recv_error(sk, msg, len); 642 643 skb = skb_recv_datagram(sk, flags, noblock, &err); 644 if (!skb) 645 goto out; 646 647 copied = skb->len; 648 if (copied > len) { 649 msg->msg_flags |= MSG_TRUNC; 650 copied = len; 651 } 652 653 /* Don't bother checking the checksum */ 654 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied); 655 if (err) 656 goto done; 657 658 sock_recv_timestamp(msg, sk, skb); 659 660 /* Copy the address. */ 661 if (sin) { 662 sin->sin_family = AF_INET; 663 sin->sin_port = 0 /* skb->h.uh->source */; 664 sin->sin_addr.s_addr = ip_hdr(skb)->saddr; 665 memset(sin->sin_zero, 0, sizeof(sin->sin_zero)); 666 } 667 if (isk->cmsg_flags) 668 ip_cmsg_recv(msg, skb); 669 err = copied; 670 671done: 672 skb_free_datagram(sk, skb); 673out: 674 pr_debug("ping_recvmsg -> %d\n", err); 675 return err; 676} 677 678static int ping_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 679{ 680 pr_debug("ping_queue_rcv_skb(sk=%p,sk->num=%d,skb=%p)\n", 681 inet_sk(sk), inet_sk(sk)->inet_num, skb); 682 if (sock_queue_rcv_skb(sk, skb) < 0) { 683 ICMP_INC_STATS_BH(sock_net(sk), ICMP_MIB_INERRORS); 684 kfree_skb(skb); 685 pr_debug("ping_queue_rcv_skb -> failed\n"); 686 return -1; 687 } 688 return 0; 689} 690 691 692/* 693 * All we need to do is get the socket. 694 */ 695 696void ping_rcv(struct sk_buff *skb) 697{ 698 struct sock *sk; 699 struct net *net = dev_net(skb->dev); 700 struct iphdr *iph = ip_hdr(skb); 701 struct icmphdr *icmph = icmp_hdr(skb); 702 u32 saddr = iph->saddr; 703 u32 daddr = iph->daddr; 704 705 /* We assume the packet has already been checked by icmp_rcv */ 706 707 pr_debug("ping_rcv(skb=%p,id=%04x,seq=%04x)\n", 708 skb, ntohs(icmph->un.echo.id), ntohs(icmph->un.echo.sequence)); 709 710 /* Push ICMP header back */ 711 skb_push(skb, skb->data - (u8 *)icmph); 712 713 sk = ping_v4_lookup(net, saddr, daddr, ntohs(icmph->un.echo.id), 714 skb->dev->ifindex); 715 if (sk != NULL) { 716 pr_debug("rcv on socket %p\n", sk); 717 ping_queue_rcv_skb(sk, skb_get(skb)); 718 sock_put(sk); 719 return; 720 } 721 pr_debug("no socket, dropping\n"); 722 723 /* We're called from icmp_rcv(). kfree_skb() is done there. */ 724} 725 726struct proto ping_prot = { 727 .name = "PING", 728 .owner = THIS_MODULE, 729 .init = ping_init_sock, 730 .close = ping_close, 731 .connect = ip4_datagram_connect, 732 .disconnect = udp_disconnect, 733 .setsockopt = ip_setsockopt, 734 .getsockopt = ip_getsockopt, 735 .sendmsg = ping_sendmsg, 736 .recvmsg = ping_recvmsg, 737 .bind = ping_bind, 738 .backlog_rcv = ping_queue_rcv_skb, 739 .hash = ping_v4_hash, 740 .unhash = ping_v4_unhash, 741 .get_port = ping_v4_get_port, 742 .obj_size = sizeof(struct inet_sock), 743}; 744EXPORT_SYMBOL(ping_prot); 745 746#ifdef CONFIG_PROC_FS 747 748static struct sock *ping_get_first(struct seq_file *seq, int start) 749{ 750 struct sock *sk; 751 struct ping_iter_state *state = seq->private; 752 struct net *net = seq_file_net(seq); 753 754 for (state->bucket = start; state->bucket < PING_HTABLE_SIZE; 755 ++state->bucket) { 756 struct hlist_nulls_node *node; 757 struct hlist_nulls_head *hslot = &ping_table.hash[state->bucket]; 758 759 if (hlist_nulls_empty(hslot)) 760 continue; 761 762 sk_nulls_for_each(sk, node, hslot) { 763 if (net_eq(sock_net(sk), net)) 764 goto found; 765 } 766 } 767 sk = NULL; 768found: 769 return sk; 770} 771 772static struct sock *ping_get_next(struct seq_file *seq, struct sock *sk) 773{ 774 struct ping_iter_state *state = seq->private; 775 struct net *net = seq_file_net(seq); 776 777 do { 778 sk = sk_nulls_next(sk); 779 } while (sk && (!net_eq(sock_net(sk), net))); 780 781 if (!sk) 782 return ping_get_first(seq, state->bucket + 1); 783 return sk; 784} 785 786static struct sock *ping_get_idx(struct seq_file *seq, loff_t pos) 787{ 788 struct sock *sk = ping_get_first(seq, 0); 789 790 if (sk) 791 while (pos && (sk = ping_get_next(seq, sk)) != NULL) 792 --pos; 793 return pos ? NULL : sk; 794} 795 796static void *ping_seq_start(struct seq_file *seq, loff_t *pos) 797{ 798 struct ping_iter_state *state = seq->private; 799 state->bucket = 0; 800 801 read_lock_bh(&ping_table.lock); 802 803 return *pos ? ping_get_idx(seq, *pos-1) : SEQ_START_TOKEN; 804} 805 806static void *ping_seq_next(struct seq_file *seq, void *v, loff_t *pos) 807{ 808 struct sock *sk; 809 810 if (v == SEQ_START_TOKEN) 811 sk = ping_get_idx(seq, 0); 812 else 813 sk = ping_get_next(seq, v); 814 815 ++*pos; 816 return sk; 817} 818 819static void ping_seq_stop(struct seq_file *seq, void *v) 820{ 821 read_unlock_bh(&ping_table.lock); 822} 823 824static void ping_format_sock(struct sock *sp, struct seq_file *f, 825 int bucket, int *len) 826{ 827 struct inet_sock *inet = inet_sk(sp); 828 __be32 dest = inet->inet_daddr; 829 __be32 src = inet->inet_rcv_saddr; 830 __u16 destp = ntohs(inet->inet_dport); 831 __u16 srcp = ntohs(inet->inet_sport); 832 833 seq_printf(f, "%5d: %08X:%04X %08X:%04X" 834 " %02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %pK %d%n", 835 bucket, src, srcp, dest, destp, sp->sk_state, 836 sk_wmem_alloc_get(sp), 837 sk_rmem_alloc_get(sp), 838 0, 0L, 0, sock_i_uid(sp), 0, sock_i_ino(sp), 839 atomic_read(&sp->sk_refcnt), sp, 840 atomic_read(&sp->sk_drops), len); 841} 842 843static int ping_seq_show(struct seq_file *seq, void *v) 844{ 845 if (v == SEQ_START_TOKEN) 846 seq_printf(seq, "%-127s\n", 847 " sl local_address rem_address st tx_queue " 848 "rx_queue tr tm->when retrnsmt uid timeout " 849 "inode ref pointer drops"); 850 else { 851 struct ping_iter_state *state = seq->private; 852 int len; 853 854 ping_format_sock(v, seq, state->bucket, &len); 855 seq_printf(seq, "%*s\n", 127 - len, ""); 856 } 857 return 0; 858} 859 860static const struct seq_operations ping_seq_ops = { 861 .show = ping_seq_show, 862 .start = ping_seq_start, 863 .next = ping_seq_next, 864 .stop = ping_seq_stop, 865}; 866 867static int ping_seq_open(struct inode *inode, struct file *file) 868{ 869 return seq_open_net(inode, file, &ping_seq_ops, 870 sizeof(struct ping_iter_state)); 871} 872 873static const struct file_operations ping_seq_fops = { 874 .open = ping_seq_open, 875 .read = seq_read, 876 .llseek = seq_lseek, 877 .release = seq_release_net, 878}; 879 880static int ping_proc_register(struct net *net) 881{ 882 struct proc_dir_entry *p; 883 int rc = 0; 884 885 p = proc_net_fops_create(net, "icmp", S_IRUGO, &ping_seq_fops); 886 if (!p) 887 rc = -ENOMEM; 888 return rc; 889} 890 891static void ping_proc_unregister(struct net *net) 892{ 893 proc_net_remove(net, "icmp"); 894} 895 896 897static int __net_init ping_proc_init_net(struct net *net) 898{ 899 return ping_proc_register(net); 900} 901 902static void __net_exit ping_proc_exit_net(struct net *net) 903{ 904 ping_proc_unregister(net); 905} 906 907static struct pernet_operations ping_net_ops = { 908 .init = ping_proc_init_net, 909 .exit = ping_proc_exit_net, 910}; 911 912int __init ping_proc_init(void) 913{ 914 return register_pernet_subsys(&ping_net_ops); 915} 916 917void ping_proc_exit(void) 918{ 919 unregister_pernet_subsys(&ping_net_ops); 920} 921 922#endif 923 924void __init ping_init(void) 925{ 926 int i; 927 928 for (i = 0; i < PING_HTABLE_SIZE; i++) 929 INIT_HLIST_NULLS_HEAD(&ping_table.hash[i], i); 930 rwlock_init(&ping_table.lock); 931} 932