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 <linux/uaccess.h> 24 #include <linux/types.h> 25 #include <linux/fcntl.h> 26 #include <linux/socket.h> 27 #include <linux/sockios.h> 28 #include <linux/in.h> 29 #include <linux/errno.h> 30 #include <linux/timer.h> 31 #include <linux/mm.h> 32 #include <linux/inet.h> 33 #include <linux/netdevice.h> 34 #include <net/snmp.h> 35 #include <net/ip.h> 36 #include <net/ipv6.h> 37 #include <net/icmp.h> 38 #include <net/protocol.h> 39 #include <linux/skbuff.h> 40 #include <linux/proc_fs.h> 41 #include <linux/export.h> 42 #include <net/sock.h> 43 #include <net/ping.h> 44 #include <net/udp.h> 45 #include <net/route.h> 46 #include <net/inet_common.h> 47 #include <net/checksum.h> 48 49 50 static struct ping_table ping_table; 51 52 static u16 ping_port_rover; 53 54 static inline int ping_hashfn(struct net *net, unsigned num, unsigned mask) 55 { 56 int res = (num + net_hash_mix(net)) & mask; 57 pr_debug("hash(%d) = %d\n", num, res); 58 return res; 59 } 60 61 static inline struct hlist_nulls_head *ping_hashslot(struct ping_table *table, 62 struct net *net, unsigned num) 63 { 64 return &table->hash[ping_hashfn(net, num, PING_HTABLE_MASK)]; 65 } 66 67 static int ping_v4_get_port(struct sock *sk, unsigned short ident) 68 { 69 struct hlist_nulls_node *node; 70 struct hlist_nulls_head *hlist; 71 struct inet_sock *isk, *isk2; 72 struct sock *sk2 = NULL; 73 74 isk = inet_sk(sk); 75 write_lock_bh(&ping_table.lock); 76 if (ident == 0) { 77 u32 i; 78 u16 result = ping_port_rover + 1; 79 80 for (i = 0; i < (1L << 16); i++, result++) { 81 if (!result) 82 result++; /* avoid zero */ 83 hlist = ping_hashslot(&ping_table, sock_net(sk), 84 result); 85 ping_portaddr_for_each_entry(sk2, node, hlist) { 86 isk2 = inet_sk(sk2); 87 88 if (isk2->inet_num == result) 89 goto next_port; 90 } 91 92 /* found */ 93 ping_port_rover = ident = result; 94 break; 95 next_port: 96 ; 97 } 98 if (i >= (1L << 16)) 99 goto fail; 100 } else { 101 hlist = ping_hashslot(&ping_table, sock_net(sk), ident); 102 ping_portaddr_for_each_entry(sk2, node, hlist) { 103 isk2 = inet_sk(sk2); 104 105 if ((isk2->inet_num == ident) && 106 (sk2 != sk) && 107 (!sk2->sk_reuse || !sk->sk_reuse)) 108 goto fail; 109 } 110 } 111 112 pr_debug("found port/ident = %d\n", ident); 113 isk->inet_num = ident; 114 if (sk_unhashed(sk)) { 115 pr_debug("was not hashed\n"); 116 sock_hold(sk); 117 hlist_nulls_add_head(&sk->sk_nulls_node, hlist); 118 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1); 119 } 120 write_unlock_bh(&ping_table.lock); 121 return 0; 122 123 fail: 124 write_unlock_bh(&ping_table.lock); 125 return 1; 126 } 127 128 static void ping_v4_hash(struct sock *sk) 129 { 130 pr_debug("ping_v4_hash(sk->port=%u)\n", inet_sk(sk)->inet_num); 131 BUG(); /* "Please do not press this button again." */ 132 } 133 134 static void ping_v4_unhash(struct sock *sk) 135 { 136 struct inet_sock *isk = inet_sk(sk); 137 pr_debug("ping_v4_unhash(isk=%p,isk->num=%u)\n", isk, isk->inet_num); 138 if (sk_hashed(sk)) { 139 write_lock_bh(&ping_table.lock); 140 hlist_nulls_del(&sk->sk_nulls_node); 141 sock_put(sk); 142 isk->inet_num = 0; 143 isk->inet_sport = 0; 144 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1); 145 write_unlock_bh(&ping_table.lock); 146 } 147 } 148 149 static struct sock *ping_v4_lookup(struct net *net, __be32 saddr, __be32 daddr, 150 u16 ident, int dif) 151 { 152 struct hlist_nulls_head *hslot = ping_hashslot(&ping_table, net, ident); 153 struct sock *sk = NULL; 154 struct inet_sock *isk; 155 struct hlist_nulls_node *hnode; 156 157 pr_debug("try to find: num = %d, daddr = %pI4, dif = %d\n", 158 (int)ident, &daddr, dif); 159 read_lock_bh(&ping_table.lock); 160 161 ping_portaddr_for_each_entry(sk, hnode, hslot) { 162 isk = inet_sk(sk); 163 164 pr_debug("found: %p: num = %d, daddr = %pI4, dif = %d\n", sk, 165 (int)isk->inet_num, &isk->inet_rcv_saddr, 166 sk->sk_bound_dev_if); 167 168 pr_debug("iterate\n"); 169 if (isk->inet_num != ident) 170 continue; 171 if (isk->inet_rcv_saddr && isk->inet_rcv_saddr != daddr) 172 continue; 173 if (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif) 174 continue; 175 176 sock_hold(sk); 177 goto exit; 178 } 179 180 sk = NULL; 181 exit: 182 read_unlock_bh(&ping_table.lock); 183 184 return sk; 185 } 186 187 static void inet_get_ping_group_range_net(struct net *net, gid_t *low, 188 gid_t *high) 189 { 190 gid_t *data = net->ipv4.sysctl_ping_group_range; 191 unsigned seq; 192 do { 193 seq = read_seqbegin(&sysctl_local_ports.lock); 194 195 *low = data[0]; 196 *high = data[1]; 197 } while (read_seqretry(&sysctl_local_ports.lock, seq)); 198 } 199 200 201 static int ping_init_sock(struct sock *sk) 202 { 203 struct net *net = sock_net(sk); 204 gid_t group = current_egid(); 205 gid_t range[2]; 206 struct group_info *group_info = get_current_groups(); 207 int i, j, count = group_info->ngroups; 208 209 inet_get_ping_group_range_net(net, range, range+1); 210 if (range[0] <= group && group <= range[1]) 211 return 0; 212 213 for (i = 0; i < group_info->nblocks; i++) { 214 int cp_count = min_t(int, NGROUPS_PER_BLOCK, count); 215 216 for (j = 0; j < cp_count; j++) { 217 group = group_info->blocks[i][j]; 218 if (range[0] <= group && group <= range[1]) 219 return 0; 220 } 221 222 count -= cp_count; 223 } 224 225 return -EACCES; 226 } 227 228 static void ping_close(struct sock *sk, long timeout) 229 { 230 pr_debug("ping_close(sk=%p,sk->num=%u)\n", 231 inet_sk(sk), inet_sk(sk)->inet_num); 232 pr_debug("isk->refcnt = %d\n", sk->sk_refcnt.counter); 233 234 sk_common_release(sk); 235 } 236 237 /* 238 * We need our own bind because there are no privileged id's == local ports. 239 * Moreover, we don't allow binding to multi- and broadcast addresses. 240 */ 241 242 static int ping_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len) 243 { 244 struct sockaddr_in *addr = (struct sockaddr_in *)uaddr; 245 struct inet_sock *isk = inet_sk(sk); 246 unsigned short snum; 247 int chk_addr_ret; 248 int err; 249 250 if (addr_len < sizeof(struct sockaddr_in)) 251 return -EINVAL; 252 253 pr_debug("ping_v4_bind(sk=%p,sa_addr=%08x,sa_port=%d)\n", 254 sk, addr->sin_addr.s_addr, ntohs(addr->sin_port)); 255 256 chk_addr_ret = inet_addr_type(sock_net(sk), addr->sin_addr.s_addr); 257 if (addr->sin_addr.s_addr == htonl(INADDR_ANY)) 258 chk_addr_ret = RTN_LOCAL; 259 260 if ((sysctl_ip_nonlocal_bind == 0 && 261 isk->freebind == 0 && isk->transparent == 0 && 262 chk_addr_ret != RTN_LOCAL) || 263 chk_addr_ret == RTN_MULTICAST || 264 chk_addr_ret == RTN_BROADCAST) 265 return -EADDRNOTAVAIL; 266 267 lock_sock(sk); 268 269 err = -EINVAL; 270 if (isk->inet_num != 0) 271 goto out; 272 273 err = -EADDRINUSE; 274 isk->inet_rcv_saddr = isk->inet_saddr = addr->sin_addr.s_addr; 275 snum = ntohs(addr->sin_port); 276 if (ping_v4_get_port(sk, snum) != 0) { 277 isk->inet_saddr = isk->inet_rcv_saddr = 0; 278 goto out; 279 } 280 281 pr_debug("after bind(): num = %d, daddr = %pI4, dif = %d\n", 282 (int)isk->inet_num, 283 &isk->inet_rcv_saddr, 284 (int)sk->sk_bound_dev_if); 285 286 err = 0; 287 if (isk->inet_rcv_saddr) 288 sk->sk_userlocks |= SOCK_BINDADDR_LOCK; 289 if (snum) 290 sk->sk_userlocks |= SOCK_BINDPORT_LOCK; 291 isk->inet_sport = htons(isk->inet_num); 292 isk->inet_daddr = 0; 293 isk->inet_dport = 0; 294 sk_dst_reset(sk); 295 out: 296 release_sock(sk); 297 pr_debug("ping_v4_bind -> %d\n", err); 298 return err; 299 } 300 301 /* 302 * Is this a supported type of ICMP message? 303 */ 304 305 static inline int ping_supported(int type, int code) 306 { 307 if (type == ICMP_ECHO && code == 0) 308 return 1; 309 return 0; 310 } 311 312 /* 313 * This routine is called by the ICMP module when it gets some 314 * sort of error condition. 315 */ 316 317 static int ping_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); 318 319 void ping_err(struct sk_buff *skb, u32 info) 320 { 321 struct iphdr *iph = (struct iphdr *)skb->data; 322 struct icmphdr *icmph = (struct icmphdr *)(skb->data+(iph->ihl<<2)); 323 struct inet_sock *inet_sock; 324 int type = icmph->type; 325 int code = icmph->code; 326 struct net *net = dev_net(skb->dev); 327 struct sock *sk; 328 int harderr; 329 int err; 330 331 /* We assume the packet has already been checked by icmp_unreach */ 332 333 if (!ping_supported(icmph->type, icmph->code)) 334 return; 335 336 pr_debug("ping_err(type=%04x,code=%04x,id=%04x,seq=%04x)\n", type, 337 code, ntohs(icmph->un.echo.id), ntohs(icmph->un.echo.sequence)); 338 339 sk = ping_v4_lookup(net, iph->daddr, iph->saddr, 340 ntohs(icmph->un.echo.id), skb->dev->ifindex); 341 if (sk == NULL) { 342 pr_debug("no socket, dropping\n"); 343 return; /* No socket for error */ 344 } 345 pr_debug("err on socket %p\n", sk); 346 347 err = 0; 348 harderr = 0; 349 inet_sock = inet_sk(sk); 350 351 switch (type) { 352 default: 353 case ICMP_TIME_EXCEEDED: 354 err = EHOSTUNREACH; 355 break; 356 case ICMP_SOURCE_QUENCH: 357 /* This is not a real error but ping wants to see it. 358 * Report it with some fake errno. */ 359 err = EREMOTEIO; 360 break; 361 case ICMP_PARAMETERPROB: 362 err = EPROTO; 363 harderr = 1; 364 break; 365 case ICMP_DEST_UNREACH: 366 if (code == ICMP_FRAG_NEEDED) { /* Path MTU discovery */ 367 if (inet_sock->pmtudisc != IP_PMTUDISC_DONT) { 368 err = EMSGSIZE; 369 harderr = 1; 370 break; 371 } 372 goto out; 373 } 374 err = EHOSTUNREACH; 375 if (code <= NR_ICMP_UNREACH) { 376 harderr = icmp_err_convert[code].fatal; 377 err = icmp_err_convert[code].errno; 378 } 379 break; 380 case ICMP_REDIRECT: 381 /* See ICMP_SOURCE_QUENCH */ 382 err = EREMOTEIO; 383 break; 384 } 385 386 /* 387 * RFC1122: OK. Passes ICMP errors back to application, as per 388 * 4.1.3.3. 389 */ 390 if (!inet_sock->recverr) { 391 if (!harderr || sk->sk_state != TCP_ESTABLISHED) 392 goto out; 393 } else { 394 ip_icmp_error(sk, skb, err, 0 /* no remote port */, 395 info, (u8 *)icmph); 396 } 397 sk->sk_err = err; 398 sk->sk_error_report(sk); 399 out: 400 sock_put(sk); 401 } 402 403 /* 404 * Copy and checksum an ICMP Echo packet from user space into a buffer. 405 */ 406 407 struct pingfakehdr { 408 struct icmphdr icmph; 409 struct iovec *iov; 410 __wsum wcheck; 411 }; 412 413 static int ping_getfrag(void *from, char * to, 414 int offset, int fraglen, int odd, struct sk_buff *skb) 415 { 416 struct pingfakehdr *pfh = (struct pingfakehdr *)from; 417 418 if (offset == 0) { 419 if (fraglen < sizeof(struct icmphdr)) 420 BUG(); 421 if (csum_partial_copy_fromiovecend(to + sizeof(struct icmphdr), 422 pfh->iov, 0, fraglen - sizeof(struct icmphdr), 423 &pfh->wcheck)) 424 return -EFAULT; 425 426 return 0; 427 } 428 if (offset < sizeof(struct icmphdr)) 429 BUG(); 430 if (csum_partial_copy_fromiovecend 431 (to, pfh->iov, offset - sizeof(struct icmphdr), 432 fraglen, &pfh->wcheck)) 433 return -EFAULT; 434 return 0; 435 } 436 437 static int ping_push_pending_frames(struct sock *sk, struct pingfakehdr *pfh, 438 struct flowi4 *fl4) 439 { 440 struct sk_buff *skb = skb_peek(&sk->sk_write_queue); 441 442 pfh->wcheck = csum_partial((char *)&pfh->icmph, 443 sizeof(struct icmphdr), pfh->wcheck); 444 pfh->icmph.checksum = csum_fold(pfh->wcheck); 445 memcpy(icmp_hdr(skb), &pfh->icmph, sizeof(struct icmphdr)); 446 skb->ip_summed = CHECKSUM_NONE; 447 return ip_push_pending_frames(sk, fl4); 448 } 449 450 static int ping_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, 451 size_t len) 452 { 453 struct net *net = sock_net(sk); 454 struct flowi4 fl4; 455 struct inet_sock *inet = inet_sk(sk); 456 struct ipcm_cookie ipc; 457 struct icmphdr user_icmph; 458 struct pingfakehdr pfh; 459 struct rtable *rt = NULL; 460 struct ip_options_data opt_copy; 461 int free = 0; 462 __be32 saddr, daddr, faddr; 463 u8 tos; 464 int err; 465 466 pr_debug("ping_sendmsg(sk=%p,sk->num=%u)\n", inet, inet->inet_num); 467 468 469 if (len > 0xFFFF) 470 return -EMSGSIZE; 471 472 /* 473 * Check the flags. 474 */ 475 476 /* Mirror BSD error message compatibility */ 477 if (msg->msg_flags & MSG_OOB) 478 return -EOPNOTSUPP; 479 480 /* 481 * Fetch the ICMP header provided by the userland. 482 * iovec is modified! 483 */ 484 485 if (memcpy_fromiovec((u8 *)&user_icmph, msg->msg_iov, 486 sizeof(struct icmphdr))) 487 return -EFAULT; 488 if (!ping_supported(user_icmph.type, user_icmph.code)) 489 return -EINVAL; 490 491 /* 492 * Get and verify the address. 493 */ 494 495 if (msg->msg_name) { 496 struct sockaddr_in *usin = (struct sockaddr_in *)msg->msg_name; 497 if (msg->msg_namelen < sizeof(*usin)) 498 return -EINVAL; 499 if (usin->sin_family != AF_INET) 500 return -EINVAL; 501 daddr = usin->sin_addr.s_addr; 502 /* no remote port */ 503 } else { 504 if (sk->sk_state != TCP_ESTABLISHED) 505 return -EDESTADDRREQ; 506 daddr = inet->inet_daddr; 507 /* no remote port */ 508 } 509 510 ipc.addr = inet->inet_saddr; 511 ipc.opt = NULL; 512 ipc.oif = sk->sk_bound_dev_if; 513 ipc.tx_flags = 0; 514 err = sock_tx_timestamp(sk, &ipc.tx_flags); 515 if (err) 516 return err; 517 518 if (msg->msg_controllen) { 519 err = ip_cmsg_send(sock_net(sk), msg, &ipc); 520 if (err) 521 return err; 522 if (ipc.opt) 523 free = 1; 524 } 525 if (!ipc.opt) { 526 struct ip_options_rcu *inet_opt; 527 528 rcu_read_lock(); 529 inet_opt = rcu_dereference(inet->inet_opt); 530 if (inet_opt) { 531 memcpy(&opt_copy, inet_opt, 532 sizeof(*inet_opt) + inet_opt->opt.optlen); 533 ipc.opt = &opt_copy.opt; 534 } 535 rcu_read_unlock(); 536 } 537 538 saddr = ipc.addr; 539 ipc.addr = faddr = daddr; 540 541 if (ipc.opt && ipc.opt->opt.srr) { 542 if (!daddr) 543 return -EINVAL; 544 faddr = ipc.opt->opt.faddr; 545 } 546 tos = RT_TOS(inet->tos); 547 if (sock_flag(sk, SOCK_LOCALROUTE) || 548 (msg->msg_flags & MSG_DONTROUTE) || 549 (ipc.opt && ipc.opt->opt.is_strictroute)) { 550 tos |= RTO_ONLINK; 551 } 552 553 if (ipv4_is_multicast(daddr)) { 554 if (!ipc.oif) 555 ipc.oif = inet->mc_index; 556 if (!saddr) 557 saddr = inet->mc_addr; 558 } else if (!ipc.oif) 559 ipc.oif = inet->uc_index; 560 561 flowi4_init_output(&fl4, ipc.oif, sk->sk_mark, tos, 562 RT_SCOPE_UNIVERSE, sk->sk_protocol, 563 inet_sk_flowi_flags(sk), faddr, saddr, 0, 0); 564 565 security_sk_classify_flow(sk, flowi4_to_flowi(&fl4)); 566 rt = ip_route_output_flow(net, &fl4, sk); 567 if (IS_ERR(rt)) { 568 err = PTR_ERR(rt); 569 rt = NULL; 570 if (err == -ENETUNREACH) 571 IP_INC_STATS_BH(net, IPSTATS_MIB_OUTNOROUTES); 572 goto out; 573 } 574 575 err = -EACCES; 576 if ((rt->rt_flags & RTCF_BROADCAST) && 577 !sock_flag(sk, SOCK_BROADCAST)) 578 goto out; 579 580 if (msg->msg_flags & MSG_CONFIRM) 581 goto do_confirm; 582 back_from_confirm: 583 584 if (!ipc.addr) 585 ipc.addr = fl4.daddr; 586 587 lock_sock(sk); 588 589 pfh.icmph.type = user_icmph.type; /* already checked */ 590 pfh.icmph.code = user_icmph.code; /* ditto */ 591 pfh.icmph.checksum = 0; 592 pfh.icmph.un.echo.id = inet->inet_sport; 593 pfh.icmph.un.echo.sequence = user_icmph.un.echo.sequence; 594 pfh.iov = msg->msg_iov; 595 pfh.wcheck = 0; 596 597 err = ip_append_data(sk, &fl4, ping_getfrag, &pfh, len, 598 0, &ipc, &rt, msg->msg_flags); 599 if (err) 600 ip_flush_pending_frames(sk); 601 else 602 err = ping_push_pending_frames(sk, &pfh, &fl4); 603 release_sock(sk); 604 605 out: 606 ip_rt_put(rt); 607 if (free) 608 kfree(ipc.opt); 609 if (!err) { 610 icmp_out_count(sock_net(sk), user_icmph.type); 611 return len; 612 } 613 return err; 614 615 do_confirm: 616 dst_confirm(&rt->dst); 617 if (!(msg->msg_flags & MSG_PROBE) || len) 618 goto back_from_confirm; 619 err = 0; 620 goto out; 621 } 622 623 static int ping_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, 624 size_t len, int noblock, int flags, int *addr_len) 625 { 626 struct inet_sock *isk = inet_sk(sk); 627 struct sockaddr_in *sin = (struct sockaddr_in *)msg->msg_name; 628 struct sk_buff *skb; 629 int copied, err; 630 631 pr_debug("ping_recvmsg(sk=%p,sk->num=%u)\n", isk, isk->inet_num); 632 633 err = -EOPNOTSUPP; 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; 670 671 done: 672 skb_free_datagram(sk, skb); 673 out: 674 pr_debug("ping_recvmsg -> %d\n", err); 675 return err; 676 } 677 678 static 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 kfree_skb(skb); 684 pr_debug("ping_queue_rcv_skb -> failed\n"); 685 return -1; 686 } 687 return 0; 688 } 689 690 691 /* 692 * All we need to do is get the socket. 693 */ 694 695 void ping_rcv(struct sk_buff *skb) 696 { 697 struct sock *sk; 698 struct net *net = dev_net(skb->dev); 699 struct iphdr *iph = ip_hdr(skb); 700 struct icmphdr *icmph = icmp_hdr(skb); 701 __be32 saddr = iph->saddr; 702 __be32 daddr = iph->daddr; 703 704 /* We assume the packet has already been checked by icmp_rcv */ 705 706 pr_debug("ping_rcv(skb=%p,id=%04x,seq=%04x)\n", 707 skb, ntohs(icmph->un.echo.id), ntohs(icmph->un.echo.sequence)); 708 709 /* Push ICMP header back */ 710 skb_push(skb, skb->data - (u8 *)icmph); 711 712 sk = ping_v4_lookup(net, saddr, daddr, ntohs(icmph->un.echo.id), 713 skb->dev->ifindex); 714 if (sk != NULL) { 715 pr_debug("rcv on socket %p\n", sk); 716 ping_queue_rcv_skb(sk, skb_get(skb)); 717 sock_put(sk); 718 return; 719 } 720 pr_debug("no socket, dropping\n"); 721 722 /* We're called from icmp_rcv(). kfree_skb() is done there. */ 723 } 724 725 struct proto ping_prot = { 726 .name = "PING", 727 .owner = THIS_MODULE, 728 .init = ping_init_sock, 729 .close = ping_close, 730 .connect = ip4_datagram_connect, 731 .disconnect = udp_disconnect, 732 .setsockopt = ip_setsockopt, 733 .getsockopt = ip_getsockopt, 734 .sendmsg = ping_sendmsg, 735 .recvmsg = ping_recvmsg, 736 .bind = ping_bind, 737 .backlog_rcv = ping_queue_rcv_skb, 738 .hash = ping_v4_hash, 739 .unhash = ping_v4_unhash, 740 .get_port = ping_v4_get_port, 741 .obj_size = sizeof(struct inet_sock), 742 }; 743 EXPORT_SYMBOL(ping_prot); 744 745 #ifdef CONFIG_PROC_FS 746 747 static struct sock *ping_get_first(struct seq_file *seq, int start) 748 { 749 struct sock *sk; 750 struct ping_iter_state *state = seq->private; 751 struct net *net = seq_file_net(seq); 752 753 for (state->bucket = start; state->bucket < PING_HTABLE_SIZE; 754 ++state->bucket) { 755 struct hlist_nulls_node *node; 756 struct hlist_nulls_head *hslot; 757 758 hslot = &ping_table.hash[state->bucket]; 759 760 if (hlist_nulls_empty(hslot)) 761 continue; 762 763 sk_nulls_for_each(sk, node, hslot) { 764 if (net_eq(sock_net(sk), net)) 765 goto found; 766 } 767 } 768 sk = NULL; 769 found: 770 return sk; 771 } 772 773 static struct sock *ping_get_next(struct seq_file *seq, struct sock *sk) 774 { 775 struct ping_iter_state *state = seq->private; 776 struct net *net = seq_file_net(seq); 777 778 do { 779 sk = sk_nulls_next(sk); 780 } while (sk && (!net_eq(sock_net(sk), net))); 781 782 if (!sk) 783 return ping_get_first(seq, state->bucket + 1); 784 return sk; 785 } 786 787 static struct sock *ping_get_idx(struct seq_file *seq, loff_t pos) 788 { 789 struct sock *sk = ping_get_first(seq, 0); 790 791 if (sk) 792 while (pos && (sk = ping_get_next(seq, sk)) != NULL) 793 --pos; 794 return pos ? NULL : sk; 795 } 796 797 static void *ping_seq_start(struct seq_file *seq, loff_t *pos) 798 { 799 struct ping_iter_state *state = seq->private; 800 state->bucket = 0; 801 802 read_lock_bh(&ping_table.lock); 803 804 return *pos ? ping_get_idx(seq, *pos-1) : SEQ_START_TOKEN; 805 } 806 807 static void *ping_seq_next(struct seq_file *seq, void *v, loff_t *pos) 808 { 809 struct sock *sk; 810 811 if (v == SEQ_START_TOKEN) 812 sk = ping_get_idx(seq, 0); 813 else 814 sk = ping_get_next(seq, v); 815 816 ++*pos; 817 return sk; 818 } 819 820 static void ping_seq_stop(struct seq_file *seq, void *v) 821 { 822 read_unlock_bh(&ping_table.lock); 823 } 824 825 static void ping_format_sock(struct sock *sp, struct seq_file *f, 826 int bucket, int *len) 827 { 828 struct inet_sock *inet = inet_sk(sp); 829 __be32 dest = inet->inet_daddr; 830 __be32 src = inet->inet_rcv_saddr; 831 __u16 destp = ntohs(inet->inet_dport); 832 __u16 srcp = ntohs(inet->inet_sport); 833 834 seq_printf(f, "%5d: %08X:%04X %08X:%04X" 835 " %02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %pK %d%n", 836 bucket, src, srcp, dest, destp, sp->sk_state, 837 sk_wmem_alloc_get(sp), 838 sk_rmem_alloc_get(sp), 839 0, 0L, 0, sock_i_uid(sp), 0, sock_i_ino(sp), 840 atomic_read(&sp->sk_refcnt), sp, 841 atomic_read(&sp->sk_drops), len); 842 } 843 844 static int ping_seq_show(struct seq_file *seq, void *v) 845 { 846 if (v == SEQ_START_TOKEN) 847 seq_printf(seq, "%-127s\n", 848 " sl local_address rem_address st tx_queue " 849 "rx_queue tr tm->when retrnsmt uid timeout " 850 "inode ref pointer drops"); 851 else { 852 struct ping_iter_state *state = seq->private; 853 int len; 854 855 ping_format_sock(v, seq, state->bucket, &len); 856 seq_printf(seq, "%*s\n", 127 - len, ""); 857 } 858 return 0; 859 } 860 861 static const struct seq_operations ping_seq_ops = { 862 .show = ping_seq_show, 863 .start = ping_seq_start, 864 .next = ping_seq_next, 865 .stop = ping_seq_stop, 866 }; 867 868 static int ping_seq_open(struct inode *inode, struct file *file) 869 { 870 return seq_open_net(inode, file, &ping_seq_ops, 871 sizeof(struct ping_iter_state)); 872 } 873 874 static const struct file_operations ping_seq_fops = { 875 .open = ping_seq_open, 876 .read = seq_read, 877 .llseek = seq_lseek, 878 .release = seq_release_net, 879 }; 880 881 static int ping_proc_register(struct net *net) 882 { 883 struct proc_dir_entry *p; 884 int rc = 0; 885 886 p = proc_net_fops_create(net, "icmp", S_IRUGO, &ping_seq_fops); 887 if (!p) 888 rc = -ENOMEM; 889 return rc; 890 } 891 892 static void ping_proc_unregister(struct net *net) 893 { 894 proc_net_remove(net, "icmp"); 895 } 896 897 898 static int __net_init ping_proc_init_net(struct net *net) 899 { 900 return ping_proc_register(net); 901 } 902 903 static void __net_exit ping_proc_exit_net(struct net *net) 904 { 905 ping_proc_unregister(net); 906 } 907 908 static struct pernet_operations ping_net_ops = { 909 .init = ping_proc_init_net, 910 .exit = ping_proc_exit_net, 911 }; 912 913 int __init ping_proc_init(void) 914 { 915 return register_pernet_subsys(&ping_net_ops); 916 } 917 918 void ping_proc_exit(void) 919 { 920 unregister_pernet_subsys(&ping_net_ops); 921 } 922 923 #endif 924 925 void __init ping_init(void) 926 { 927 int i; 928 929 for (i = 0; i < PING_HTABLE_SIZE; i++) 930 INIT_HLIST_NULLS_HEAD(&ping_table.hash[i], i); 931 rwlock_init(&ping_table.lock); 932 } 933