ping.c revision 4330487acfff0cf1d7b14d238583a182e0a444bb
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/icmp.h> 37#include <net/protocol.h> 38#include <linux/skbuff.h> 39#include <linux/proc_fs.h> 40#include <linux/export.h> 41#include <net/sock.h> 42#include <net/ping.h> 43#include <net/udp.h> 44#include <net/route.h> 45#include <net/inet_common.h> 46#include <net/checksum.h> 47 48#if IS_ENABLED(CONFIG_IPV6) 49#include <linux/in6.h> 50#include <linux/icmpv6.h> 51#include <net/addrconf.h> 52#include <net/ipv6.h> 53#include <net/transp_v6.h> 54#endif 55 56struct ping_table { 57 struct hlist_nulls_head hash[PING_HTABLE_SIZE]; 58 rwlock_t lock; 59}; 60 61static struct ping_table ping_table; 62struct pingv6_ops pingv6_ops; 63EXPORT_SYMBOL_GPL(pingv6_ops); 64 65static u16 ping_port_rover; 66 67static inline int ping_hashfn(struct net *net, unsigned int num, unsigned int mask) 68{ 69 int res = (num + net_hash_mix(net)) & mask; 70 71 pr_debug("hash(%d) = %d\n", num, res); 72 return res; 73} 74EXPORT_SYMBOL_GPL(ping_hash); 75 76static inline struct hlist_nulls_head *ping_hashslot(struct ping_table *table, 77 struct net *net, unsigned int num) 78{ 79 return &table->hash[ping_hashfn(net, num, PING_HTABLE_MASK)]; 80} 81 82int ping_get_port(struct sock *sk, unsigned short ident) 83{ 84 struct hlist_nulls_node *node; 85 struct hlist_nulls_head *hlist; 86 struct inet_sock *isk, *isk2; 87 struct sock *sk2 = NULL; 88 89 isk = inet_sk(sk); 90 write_lock_bh(&ping_table.lock); 91 if (ident == 0) { 92 u32 i; 93 u16 result = ping_port_rover + 1; 94 95 for (i = 0; i < (1L << 16); i++, result++) { 96 if (!result) 97 result++; /* avoid zero */ 98 hlist = ping_hashslot(&ping_table, sock_net(sk), 99 result); 100 ping_portaddr_for_each_entry(sk2, node, hlist) { 101 isk2 = inet_sk(sk2); 102 103 if (isk2->inet_num == result) 104 goto next_port; 105 } 106 107 /* found */ 108 ping_port_rover = ident = result; 109 break; 110next_port: 111 ; 112 } 113 if (i >= (1L << 16)) 114 goto fail; 115 } else { 116 hlist = ping_hashslot(&ping_table, sock_net(sk), ident); 117 ping_portaddr_for_each_entry(sk2, node, hlist) { 118 isk2 = inet_sk(sk2); 119 120 /* BUG? Why is this reuse and not reuseaddr? ping.c 121 * doesn't turn off SO_REUSEADDR, and it doesn't expect 122 * that other ping processes can steal its packets. 123 */ 124 if ((isk2->inet_num == ident) && 125 (sk2 != sk) && 126 (!sk2->sk_reuse || !sk->sk_reuse)) 127 goto fail; 128 } 129 } 130 131 pr_debug("found port/ident = %d\n", ident); 132 isk->inet_num = ident; 133 if (sk_unhashed(sk)) { 134 pr_debug("was not hashed\n"); 135 sock_hold(sk); 136 hlist_nulls_add_head(&sk->sk_nulls_node, hlist); 137 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1); 138 } 139 write_unlock_bh(&ping_table.lock); 140 return 0; 141 142fail: 143 write_unlock_bh(&ping_table.lock); 144 return 1; 145} 146EXPORT_SYMBOL_GPL(ping_get_port); 147 148void ping_hash(struct sock *sk) 149{ 150 pr_debug("ping_hash(sk->port=%u)\n", inet_sk(sk)->inet_num); 151 BUG(); /* "Please do not press this button again." */ 152} 153 154void ping_unhash(struct sock *sk) 155{ 156 struct inet_sock *isk = inet_sk(sk); 157 pr_debug("ping_unhash(isk=%p,isk->num=%u)\n", isk, isk->inet_num); 158 if (sk_hashed(sk)) { 159 write_lock_bh(&ping_table.lock); 160 hlist_nulls_del(&sk->sk_nulls_node); 161 sock_put(sk); 162 isk->inet_num = 0; 163 isk->inet_sport = 0; 164 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1); 165 write_unlock_bh(&ping_table.lock); 166 } 167} 168EXPORT_SYMBOL_GPL(ping_unhash); 169 170static struct sock *ping_lookup(struct net *net, struct sk_buff *skb, u16 ident) 171{ 172 struct hlist_nulls_head *hslot = ping_hashslot(&ping_table, net, ident); 173 struct sock *sk = NULL; 174 struct inet_sock *isk; 175 struct hlist_nulls_node *hnode; 176 int dif = skb->dev->ifindex; 177 178 if (skb->protocol == htons(ETH_P_IP)) { 179 pr_debug("try to find: num = %d, daddr = %pI4, dif = %d\n", 180 (int)ident, &ip_hdr(skb)->daddr, dif); 181#if IS_ENABLED(CONFIG_IPV6) 182 } else if (skb->protocol == htons(ETH_P_IPV6)) { 183 pr_debug("try to find: num = %d, daddr = %pI6c, dif = %d\n", 184 (int)ident, &ipv6_hdr(skb)->daddr, dif); 185#endif 186 } 187 188 read_lock_bh(&ping_table.lock); 189 190 ping_portaddr_for_each_entry(sk, hnode, hslot) { 191 isk = inet_sk(sk); 192 193 pr_debug("iterate\n"); 194 if (isk->inet_num != ident) 195 continue; 196 197 if (skb->protocol == htons(ETH_P_IP) && 198 sk->sk_family == AF_INET) { 199 pr_debug("found: %p: num=%d, daddr=%pI4, dif=%d\n", sk, 200 (int) isk->inet_num, &isk->inet_rcv_saddr, 201 sk->sk_bound_dev_if); 202 203 if (isk->inet_rcv_saddr && 204 isk->inet_rcv_saddr != ip_hdr(skb)->daddr) 205 continue; 206#if IS_ENABLED(CONFIG_IPV6) 207 } else if (skb->protocol == htons(ETH_P_IPV6) && 208 sk->sk_family == AF_INET6) { 209 210 pr_debug("found: %p: num=%d, daddr=%pI6c, dif=%d\n", sk, 211 (int) isk->inet_num, 212 &sk->sk_v6_rcv_saddr, 213 sk->sk_bound_dev_if); 214 215 if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr) && 216 !ipv6_addr_equal(&sk->sk_v6_rcv_saddr, 217 &ipv6_hdr(skb)->daddr)) 218 continue; 219#endif 220 } 221 222 if (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif) 223 continue; 224 225 sock_hold(sk); 226 goto exit; 227 } 228 229 sk = NULL; 230exit: 231 read_unlock_bh(&ping_table.lock); 232 233 return sk; 234} 235 236static void inet_get_ping_group_range_net(struct net *net, kgid_t *low, 237 kgid_t *high) 238{ 239 kgid_t *data = net->ipv4.ping_group_range.range; 240 unsigned int seq; 241 242 do { 243 seq = read_seqbegin(&net->ipv4.ping_group_range.lock); 244 245 *low = data[0]; 246 *high = data[1]; 247 } while (read_seqretry(&net->ipv4.ping_group_range.lock, seq)); 248} 249 250 251int ping_init_sock(struct sock *sk) 252{ 253 struct net *net = sock_net(sk); 254 kgid_t group = current_egid(); 255 struct group_info *group_info; 256 int i, j, count; 257 kgid_t low, high; 258 int ret = 0; 259 260 inet_get_ping_group_range_net(net, &low, &high); 261 if (gid_lte(low, group) && gid_lte(group, high)) 262 return 0; 263 264 group_info = get_current_groups(); 265 count = group_info->ngroups; 266 for (i = 0; i < group_info->nblocks; i++) { 267 int cp_count = min_t(int, NGROUPS_PER_BLOCK, count); 268 for (j = 0; j < cp_count; j++) { 269 kgid_t gid = group_info->blocks[i][j]; 270 if (gid_lte(low, gid) && gid_lte(gid, high)) 271 goto out_release_group; 272 } 273 274 count -= cp_count; 275 } 276 277 ret = -EACCES; 278 279out_release_group: 280 put_group_info(group_info); 281 return ret; 282} 283EXPORT_SYMBOL_GPL(ping_init_sock); 284 285void ping_close(struct sock *sk, long timeout) 286{ 287 pr_debug("ping_close(sk=%p,sk->num=%u)\n", 288 inet_sk(sk), inet_sk(sk)->inet_num); 289 pr_debug("isk->refcnt = %d\n", sk->sk_refcnt.counter); 290 291 sk_common_release(sk); 292} 293EXPORT_SYMBOL_GPL(ping_close); 294 295/* Checks the bind address and possibly modifies sk->sk_bound_dev_if. */ 296static int ping_check_bind_addr(struct sock *sk, struct inet_sock *isk, 297 struct sockaddr *uaddr, int addr_len) { 298 struct net *net = sock_net(sk); 299 if (sk->sk_family == AF_INET) { 300 struct sockaddr_in *addr = (struct sockaddr_in *) uaddr; 301 int chk_addr_ret; 302 303 if (addr_len < sizeof(*addr)) 304 return -EINVAL; 305 306 pr_debug("ping_check_bind_addr(sk=%p,addr=%pI4,port=%d)\n", 307 sk, &addr->sin_addr.s_addr, ntohs(addr->sin_port)); 308 309 chk_addr_ret = inet_addr_type(net, addr->sin_addr.s_addr); 310 311 if (addr->sin_addr.s_addr == htonl(INADDR_ANY)) 312 chk_addr_ret = RTN_LOCAL; 313 314 if ((sysctl_ip_nonlocal_bind == 0 && 315 isk->freebind == 0 && isk->transparent == 0 && 316 chk_addr_ret != RTN_LOCAL) || 317 chk_addr_ret == RTN_MULTICAST || 318 chk_addr_ret == RTN_BROADCAST) 319 return -EADDRNOTAVAIL; 320 321#if IS_ENABLED(CONFIG_IPV6) 322 } else if (sk->sk_family == AF_INET6) { 323 struct sockaddr_in6 *addr = (struct sockaddr_in6 *) uaddr; 324 int addr_type, scoped, has_addr; 325 struct net_device *dev = NULL; 326 327 if (addr_len < sizeof(*addr)) 328 return -EINVAL; 329 330 if (addr->sin6_family != AF_INET6) 331 return -EINVAL; 332 333 pr_debug("ping_check_bind_addr(sk=%p,addr=%pI6c,port=%d)\n", 334 sk, addr->sin6_addr.s6_addr, ntohs(addr->sin6_port)); 335 336 addr_type = ipv6_addr_type(&addr->sin6_addr); 337 scoped = __ipv6_addr_needs_scope_id(addr_type); 338 if ((addr_type != IPV6_ADDR_ANY && 339 !(addr_type & IPV6_ADDR_UNICAST)) || 340 (scoped && !addr->sin6_scope_id)) 341 return -EINVAL; 342 343 rcu_read_lock(); 344 if (addr->sin6_scope_id) { 345 dev = dev_get_by_index_rcu(net, addr->sin6_scope_id); 346 if (!dev) { 347 rcu_read_unlock(); 348 return -ENODEV; 349 } 350 } 351 has_addr = pingv6_ops.ipv6_chk_addr(net, &addr->sin6_addr, dev, 352 scoped); 353 rcu_read_unlock(); 354 355 if (!(isk->freebind || isk->transparent || has_addr || 356 addr_type == IPV6_ADDR_ANY)) 357 return -EADDRNOTAVAIL; 358 359 if (scoped) 360 sk->sk_bound_dev_if = addr->sin6_scope_id; 361#endif 362 } else { 363 return -EAFNOSUPPORT; 364 } 365 return 0; 366} 367 368static void ping_set_saddr(struct sock *sk, struct sockaddr *saddr) 369{ 370 if (saddr->sa_family == AF_INET) { 371 struct inet_sock *isk = inet_sk(sk); 372 struct sockaddr_in *addr = (struct sockaddr_in *) saddr; 373 isk->inet_rcv_saddr = isk->inet_saddr = addr->sin_addr.s_addr; 374#if IS_ENABLED(CONFIG_IPV6) 375 } else if (saddr->sa_family == AF_INET6) { 376 struct sockaddr_in6 *addr = (struct sockaddr_in6 *) saddr; 377 struct ipv6_pinfo *np = inet6_sk(sk); 378 sk->sk_v6_rcv_saddr = np->saddr = addr->sin6_addr; 379#endif 380 } 381} 382 383static void ping_clear_saddr(struct sock *sk, int dif) 384{ 385 sk->sk_bound_dev_if = dif; 386 if (sk->sk_family == AF_INET) { 387 struct inet_sock *isk = inet_sk(sk); 388 isk->inet_rcv_saddr = isk->inet_saddr = 0; 389#if IS_ENABLED(CONFIG_IPV6) 390 } else if (sk->sk_family == AF_INET6) { 391 struct ipv6_pinfo *np = inet6_sk(sk); 392 memset(&sk->sk_v6_rcv_saddr, 0, sizeof(sk->sk_v6_rcv_saddr)); 393 memset(&np->saddr, 0, sizeof(np->saddr)); 394#endif 395 } 396} 397/* 398 * We need our own bind because there are no privileged id's == local ports. 399 * Moreover, we don't allow binding to multi- and broadcast addresses. 400 */ 401 402int ping_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len) 403{ 404 struct inet_sock *isk = inet_sk(sk); 405 unsigned short snum; 406 int err; 407 int dif = sk->sk_bound_dev_if; 408 409 err = ping_check_bind_addr(sk, isk, uaddr, addr_len); 410 if (err) 411 return err; 412 413 lock_sock(sk); 414 415 err = -EINVAL; 416 if (isk->inet_num != 0) 417 goto out; 418 419 err = -EADDRINUSE; 420 ping_set_saddr(sk, uaddr); 421 snum = ntohs(((struct sockaddr_in *)uaddr)->sin_port); 422 if (ping_get_port(sk, snum) != 0) { 423 ping_clear_saddr(sk, dif); 424 goto out; 425 } 426 427 pr_debug("after bind(): num = %d, dif = %d\n", 428 (int)isk->inet_num, 429 (int)sk->sk_bound_dev_if); 430 431 err = 0; 432 if (sk->sk_family == AF_INET && isk->inet_rcv_saddr) 433 sk->sk_userlocks |= SOCK_BINDADDR_LOCK; 434#if IS_ENABLED(CONFIG_IPV6) 435 if (sk->sk_family == AF_INET6 && !ipv6_addr_any(&sk->sk_v6_rcv_saddr)) 436 sk->sk_userlocks |= SOCK_BINDADDR_LOCK; 437#endif 438 439 if (snum) 440 sk->sk_userlocks |= SOCK_BINDPORT_LOCK; 441 isk->inet_sport = htons(isk->inet_num); 442 isk->inet_daddr = 0; 443 isk->inet_dport = 0; 444 445#if IS_ENABLED(CONFIG_IPV6) 446 if (sk->sk_family == AF_INET6) 447 memset(&sk->sk_v6_daddr, 0, sizeof(sk->sk_v6_daddr)); 448#endif 449 450 sk_dst_reset(sk); 451out: 452 release_sock(sk); 453 pr_debug("ping_v4_bind -> %d\n", err); 454 return err; 455} 456EXPORT_SYMBOL_GPL(ping_bind); 457 458/* 459 * Is this a supported type of ICMP message? 460 */ 461 462static inline int ping_supported(int family, int type, int code) 463{ 464 return (family == AF_INET && type == ICMP_ECHO && code == 0) || 465 (family == AF_INET6 && type == ICMPV6_ECHO_REQUEST && code == 0); 466} 467 468/* 469 * This routine is called by the ICMP module when it gets some 470 * sort of error condition. 471 */ 472 473void ping_err(struct sk_buff *skb, int offset, u32 info) 474{ 475 int family; 476 struct icmphdr *icmph; 477 struct inet_sock *inet_sock; 478 int type; 479 int code; 480 struct net *net = dev_net(skb->dev); 481 struct sock *sk; 482 int harderr; 483 int err; 484 485 if (skb->protocol == htons(ETH_P_IP)) { 486 family = AF_INET; 487 type = icmp_hdr(skb)->type; 488 code = icmp_hdr(skb)->code; 489 icmph = (struct icmphdr *)(skb->data + offset); 490 } else if (skb->protocol == htons(ETH_P_IPV6)) { 491 family = AF_INET6; 492 type = icmp6_hdr(skb)->icmp6_type; 493 code = icmp6_hdr(skb)->icmp6_code; 494 icmph = (struct icmphdr *) (skb->data + offset); 495 } else { 496 BUG(); 497 } 498 499 /* We assume the packet has already been checked by icmp_unreach */ 500 501 if (!ping_supported(family, icmph->type, icmph->code)) 502 return; 503 504 pr_debug("ping_err(proto=0x%x,type=%d,code=%d,id=%04x,seq=%04x)\n", 505 skb->protocol, type, code, ntohs(icmph->un.echo.id), 506 ntohs(icmph->un.echo.sequence)); 507 508 sk = ping_lookup(net, skb, ntohs(icmph->un.echo.id)); 509 if (sk == NULL) { 510 pr_debug("no socket, dropping\n"); 511 return; /* No socket for error */ 512 } 513 pr_debug("err on socket %p\n", sk); 514 515 err = 0; 516 harderr = 0; 517 inet_sock = inet_sk(sk); 518 519 if (skb->protocol == htons(ETH_P_IP)) { 520 switch (type) { 521 default: 522 case ICMP_TIME_EXCEEDED: 523 err = EHOSTUNREACH; 524 break; 525 case ICMP_SOURCE_QUENCH: 526 /* This is not a real error but ping wants to see it. 527 * Report it with some fake errno. 528 */ 529 err = EREMOTEIO; 530 break; 531 case ICMP_PARAMETERPROB: 532 err = EPROTO; 533 harderr = 1; 534 break; 535 case ICMP_DEST_UNREACH: 536 if (code == ICMP_FRAG_NEEDED) { /* Path MTU discovery */ 537 ipv4_sk_update_pmtu(skb, sk, info); 538 if (inet_sock->pmtudisc != IP_PMTUDISC_DONT) { 539 err = EMSGSIZE; 540 harderr = 1; 541 break; 542 } 543 goto out; 544 } 545 err = EHOSTUNREACH; 546 if (code <= NR_ICMP_UNREACH) { 547 harderr = icmp_err_convert[code].fatal; 548 err = icmp_err_convert[code].errno; 549 } 550 break; 551 case ICMP_REDIRECT: 552 /* See ICMP_SOURCE_QUENCH */ 553 ipv4_sk_redirect(skb, sk); 554 err = EREMOTEIO; 555 break; 556 } 557#if IS_ENABLED(CONFIG_IPV6) 558 } else if (skb->protocol == htons(ETH_P_IPV6)) { 559 harderr = pingv6_ops.icmpv6_err_convert(type, code, &err); 560#endif 561 } 562 563 /* 564 * RFC1122: OK. Passes ICMP errors back to application, as per 565 * 4.1.3.3. 566 */ 567 if ((family == AF_INET && !inet_sock->recverr) || 568 (family == AF_INET6 && !inet6_sk(sk)->recverr)) { 569 if (!harderr || sk->sk_state != TCP_ESTABLISHED) 570 goto out; 571 } else { 572 if (family == AF_INET) { 573 ip_icmp_error(sk, skb, err, 0 /* no remote port */, 574 info, (u8 *)icmph); 575#if IS_ENABLED(CONFIG_IPV6) 576 } else if (family == AF_INET6) { 577 pingv6_ops.ipv6_icmp_error(sk, skb, err, 0, 578 info, (u8 *)icmph); 579#endif 580 } 581 } 582 sk->sk_err = err; 583 sk->sk_error_report(sk); 584out: 585 sock_put(sk); 586} 587EXPORT_SYMBOL_GPL(ping_err); 588 589/* 590 * Copy and checksum an ICMP Echo packet from user space into a buffer 591 * starting from the payload. 592 */ 593 594int ping_getfrag(void *from, char *to, 595 int offset, int fraglen, int odd, struct sk_buff *skb) 596{ 597 struct pingfakehdr *pfh = (struct pingfakehdr *)from; 598 599 if (offset == 0) { 600 if (fraglen < sizeof(struct icmphdr)) 601 BUG(); 602 if (csum_partial_copy_fromiovecend(to + sizeof(struct icmphdr), 603 pfh->iov, 0, fraglen - sizeof(struct icmphdr), 604 &pfh->wcheck)) 605 return -EFAULT; 606 } else if (offset < sizeof(struct icmphdr)) { 607 BUG(); 608 } else { 609 if (csum_partial_copy_fromiovecend 610 (to, pfh->iov, offset - sizeof(struct icmphdr), 611 fraglen, &pfh->wcheck)) 612 return -EFAULT; 613 } 614 615#if IS_ENABLED(CONFIG_IPV6) 616 /* For IPv6, checksum each skb as we go along, as expected by 617 * icmpv6_push_pending_frames. For IPv4, accumulate the checksum in 618 * wcheck, it will be finalized in ping_v4_push_pending_frames. 619 */ 620 if (pfh->family == AF_INET6) { 621 skb->csum = pfh->wcheck; 622 skb->ip_summed = CHECKSUM_NONE; 623 pfh->wcheck = 0; 624 } 625#endif 626 627 return 0; 628} 629EXPORT_SYMBOL_GPL(ping_getfrag); 630 631static int ping_v4_push_pending_frames(struct sock *sk, struct pingfakehdr *pfh, 632 struct flowi4 *fl4) 633{ 634 struct sk_buff *skb = skb_peek(&sk->sk_write_queue); 635 636 pfh->wcheck = csum_partial((char *)&pfh->icmph, 637 sizeof(struct icmphdr), pfh->wcheck); 638 pfh->icmph.checksum = csum_fold(pfh->wcheck); 639 memcpy(icmp_hdr(skb), &pfh->icmph, sizeof(struct icmphdr)); 640 skb->ip_summed = CHECKSUM_NONE; 641 return ip_push_pending_frames(sk, fl4); 642} 643 644int ping_common_sendmsg(int family, struct msghdr *msg, size_t len, 645 void *user_icmph, size_t icmph_len) { 646 u8 type, code; 647 648 if (len > 0xFFFF) 649 return -EMSGSIZE; 650 651 /* 652 * Check the flags. 653 */ 654 655 /* Mirror BSD error message compatibility */ 656 if (msg->msg_flags & MSG_OOB) 657 return -EOPNOTSUPP; 658 659 /* 660 * Fetch the ICMP header provided by the userland. 661 * iovec is modified! The ICMP header is consumed. 662 */ 663 if (memcpy_fromiovec(user_icmph, msg->msg_iov, icmph_len)) 664 return -EFAULT; 665 666 if (family == AF_INET) { 667 type = ((struct icmphdr *) user_icmph)->type; 668 code = ((struct icmphdr *) user_icmph)->code; 669#if IS_ENABLED(CONFIG_IPV6) 670 } else if (family == AF_INET6) { 671 type = ((struct icmp6hdr *) user_icmph)->icmp6_type; 672 code = ((struct icmp6hdr *) user_icmph)->icmp6_code; 673#endif 674 } else { 675 BUG(); 676 } 677 678 if (!ping_supported(family, type, code)) 679 return -EINVAL; 680 681 return 0; 682} 683EXPORT_SYMBOL_GPL(ping_common_sendmsg); 684 685static int ping_v4_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, 686 size_t len) 687{ 688 struct net *net = sock_net(sk); 689 struct flowi4 fl4; 690 struct inet_sock *inet = inet_sk(sk); 691 struct ipcm_cookie ipc; 692 struct icmphdr user_icmph; 693 struct pingfakehdr pfh; 694 struct rtable *rt = NULL; 695 struct ip_options_data opt_copy; 696 int free = 0; 697 __be32 saddr, daddr, faddr; 698 u8 tos; 699 int err; 700 701 pr_debug("ping_v4_sendmsg(sk=%p,sk->num=%u)\n", inet, inet->inet_num); 702 703 err = ping_common_sendmsg(AF_INET, msg, len, &user_icmph, 704 sizeof(user_icmph)); 705 if (err) 706 return err; 707 708 /* 709 * Get and verify the address. 710 */ 711 712 if (msg->msg_name) { 713 DECLARE_SOCKADDR(struct sockaddr_in *, usin, msg->msg_name); 714 if (msg->msg_namelen < sizeof(*usin)) 715 return -EINVAL; 716 if (usin->sin_family != AF_INET) 717 return -EINVAL; 718 daddr = usin->sin_addr.s_addr; 719 /* no remote port */ 720 } else { 721 if (sk->sk_state != TCP_ESTABLISHED) 722 return -EDESTADDRREQ; 723 daddr = inet->inet_daddr; 724 /* no remote port */ 725 } 726 727 ipc.addr = inet->inet_saddr; 728 ipc.opt = NULL; 729 ipc.oif = sk->sk_bound_dev_if; 730 ipc.tx_flags = 0; 731 ipc.ttl = 0; 732 ipc.tos = -1; 733 734 sock_tx_timestamp(sk, &ipc.tx_flags); 735 736 if (msg->msg_controllen) { 737 err = ip_cmsg_send(sock_net(sk), msg, &ipc, false); 738 if (err) 739 return err; 740 if (ipc.opt) 741 free = 1; 742 } 743 if (!ipc.opt) { 744 struct ip_options_rcu *inet_opt; 745 746 rcu_read_lock(); 747 inet_opt = rcu_dereference(inet->inet_opt); 748 if (inet_opt) { 749 memcpy(&opt_copy, inet_opt, 750 sizeof(*inet_opt) + inet_opt->opt.optlen); 751 ipc.opt = &opt_copy.opt; 752 } 753 rcu_read_unlock(); 754 } 755 756 saddr = ipc.addr; 757 ipc.addr = faddr = daddr; 758 759 if (ipc.opt && ipc.opt->opt.srr) { 760 if (!daddr) 761 return -EINVAL; 762 faddr = ipc.opt->opt.faddr; 763 } 764 tos = get_rttos(&ipc, inet); 765 if (sock_flag(sk, SOCK_LOCALROUTE) || 766 (msg->msg_flags & MSG_DONTROUTE) || 767 (ipc.opt && ipc.opt->opt.is_strictroute)) { 768 tos |= RTO_ONLINK; 769 } 770 771 if (ipv4_is_multicast(daddr)) { 772 if (!ipc.oif) 773 ipc.oif = inet->mc_index; 774 if (!saddr) 775 saddr = inet->mc_addr; 776 } else if (!ipc.oif) 777 ipc.oif = inet->uc_index; 778 779 flowi4_init_output(&fl4, ipc.oif, sk->sk_mark, tos, 780 RT_SCOPE_UNIVERSE, sk->sk_protocol, 781 inet_sk_flowi_flags(sk), faddr, saddr, 0, 0); 782 783 security_sk_classify_flow(sk, flowi4_to_flowi(&fl4)); 784 rt = ip_route_output_flow(net, &fl4, sk); 785 if (IS_ERR(rt)) { 786 err = PTR_ERR(rt); 787 rt = NULL; 788 if (err == -ENETUNREACH) 789 IP_INC_STATS(net, IPSTATS_MIB_OUTNOROUTES); 790 goto out; 791 } 792 793 err = -EACCES; 794 if ((rt->rt_flags & RTCF_BROADCAST) && 795 !sock_flag(sk, SOCK_BROADCAST)) 796 goto out; 797 798 if (msg->msg_flags & MSG_CONFIRM) 799 goto do_confirm; 800back_from_confirm: 801 802 if (!ipc.addr) 803 ipc.addr = fl4.daddr; 804 805 lock_sock(sk); 806 807 pfh.icmph.type = user_icmph.type; /* already checked */ 808 pfh.icmph.code = user_icmph.code; /* ditto */ 809 pfh.icmph.checksum = 0; 810 pfh.icmph.un.echo.id = inet->inet_sport; 811 pfh.icmph.un.echo.sequence = user_icmph.un.echo.sequence; 812 pfh.iov = msg->msg_iov; 813 pfh.wcheck = 0; 814 pfh.family = AF_INET; 815 816 err = ip_append_data(sk, &fl4, ping_getfrag, &pfh, len, 817 0, &ipc, &rt, msg->msg_flags); 818 if (err) 819 ip_flush_pending_frames(sk); 820 else 821 err = ping_v4_push_pending_frames(sk, &pfh, &fl4); 822 release_sock(sk); 823 824out: 825 ip_rt_put(rt); 826 if (free) 827 kfree(ipc.opt); 828 if (!err) { 829 icmp_out_count(sock_net(sk), user_icmph.type); 830 return len; 831 } 832 return err; 833 834do_confirm: 835 dst_confirm(&rt->dst); 836 if (!(msg->msg_flags & MSG_PROBE) || len) 837 goto back_from_confirm; 838 err = 0; 839 goto out; 840} 841 842int ping_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, 843 size_t len, int noblock, int flags, int *addr_len) 844{ 845 struct inet_sock *isk = inet_sk(sk); 846 int family = sk->sk_family; 847 struct sk_buff *skb; 848 int copied, err; 849 850 pr_debug("ping_recvmsg(sk=%p,sk->num=%u)\n", isk, isk->inet_num); 851 852 err = -EOPNOTSUPP; 853 if (flags & MSG_OOB) 854 goto out; 855 856 if (flags & MSG_ERRQUEUE) { 857 if (family == AF_INET) { 858 return ip_recv_error(sk, msg, len, addr_len); 859#if IS_ENABLED(CONFIG_IPV6) 860 } else if (family == AF_INET6) { 861 return pingv6_ops.ipv6_recv_error(sk, msg, len, 862 addr_len); 863#endif 864 } 865 } 866 867 skb = skb_recv_datagram(sk, flags, noblock, &err); 868 if (!skb) 869 goto out; 870 871 copied = skb->len; 872 if (copied > len) { 873 msg->msg_flags |= MSG_TRUNC; 874 copied = len; 875 } 876 877 /* Don't bother checking the checksum */ 878 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied); 879 if (err) 880 goto done; 881 882 sock_recv_timestamp(msg, sk, skb); 883 884 /* Copy the address and add cmsg data. */ 885 if (family == AF_INET) { 886 DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name); 887 888 if (sin) { 889 sin->sin_family = AF_INET; 890 sin->sin_port = 0 /* skb->h.uh->source */; 891 sin->sin_addr.s_addr = ip_hdr(skb)->saddr; 892 memset(sin->sin_zero, 0, sizeof(sin->sin_zero)); 893 *addr_len = sizeof(*sin); 894 } 895 896 if (isk->cmsg_flags) 897 ip_cmsg_recv(msg, skb); 898 899#if IS_ENABLED(CONFIG_IPV6) 900 } else if (family == AF_INET6) { 901 struct ipv6_pinfo *np = inet6_sk(sk); 902 struct ipv6hdr *ip6 = ipv6_hdr(skb); 903 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name); 904 905 if (sin6) { 906 sin6->sin6_family = AF_INET6; 907 sin6->sin6_port = 0; 908 sin6->sin6_addr = ip6->saddr; 909 sin6->sin6_flowinfo = 0; 910 if (np->sndflow) 911 sin6->sin6_flowinfo = ip6_flowinfo(ip6); 912 sin6->sin6_scope_id = 913 ipv6_iface_scope_id(&sin6->sin6_addr, 914 inet6_iif(skb)); 915 *addr_len = sizeof(*sin6); 916 } 917 918 if (inet6_sk(sk)->rxopt.all) 919 pingv6_ops.ip6_datagram_recv_common_ctl(sk, msg, skb); 920 if (skb->protocol == htons(ETH_P_IPV6) && 921 inet6_sk(sk)->rxopt.all) 922 pingv6_ops.ip6_datagram_recv_specific_ctl(sk, msg, skb); 923 else if (skb->protocol == htons(ETH_P_IP) && isk->cmsg_flags) 924 ip_cmsg_recv(msg, skb); 925#endif 926 } else { 927 BUG(); 928 } 929 930 err = copied; 931 932done: 933 skb_free_datagram(sk, skb); 934out: 935 pr_debug("ping_recvmsg -> %d\n", err); 936 return err; 937} 938EXPORT_SYMBOL_GPL(ping_recvmsg); 939 940int ping_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) 941{ 942 pr_debug("ping_queue_rcv_skb(sk=%p,sk->num=%d,skb=%p)\n", 943 inet_sk(sk), inet_sk(sk)->inet_num, skb); 944 if (sock_queue_rcv_skb(sk, skb) < 0) { 945 kfree_skb(skb); 946 pr_debug("ping_queue_rcv_skb -> failed\n"); 947 return -1; 948 } 949 return 0; 950} 951EXPORT_SYMBOL_GPL(ping_queue_rcv_skb); 952 953 954/* 955 * All we need to do is get the socket. 956 */ 957 958void ping_rcv(struct sk_buff *skb) 959{ 960 struct sock *sk; 961 struct net *net = dev_net(skb->dev); 962 struct icmphdr *icmph = icmp_hdr(skb); 963 964 /* We assume the packet has already been checked by icmp_rcv */ 965 966 pr_debug("ping_rcv(skb=%p,id=%04x,seq=%04x)\n", 967 skb, ntohs(icmph->un.echo.id), ntohs(icmph->un.echo.sequence)); 968 969 /* Push ICMP header back */ 970 skb_push(skb, skb->data - (u8 *)icmph); 971 972 sk = ping_lookup(net, skb, ntohs(icmph->un.echo.id)); 973 if (sk != NULL) { 974 pr_debug("rcv on socket %p\n", sk); 975 ping_queue_rcv_skb(sk, skb_get(skb)); 976 sock_put(sk); 977 return; 978 } 979 pr_debug("no socket, dropping\n"); 980 981 /* We're called from icmp_rcv(). kfree_skb() is done there. */ 982} 983EXPORT_SYMBOL_GPL(ping_rcv); 984 985struct proto ping_prot = { 986 .name = "PING", 987 .owner = THIS_MODULE, 988 .init = ping_init_sock, 989 .close = ping_close, 990 .connect = ip4_datagram_connect, 991 .disconnect = udp_disconnect, 992 .setsockopt = ip_setsockopt, 993 .getsockopt = ip_getsockopt, 994 .sendmsg = ping_v4_sendmsg, 995 .recvmsg = ping_recvmsg, 996 .bind = ping_bind, 997 .backlog_rcv = ping_queue_rcv_skb, 998 .release_cb = ip4_datagram_release_cb, 999 .hash = ping_hash, 1000 .unhash = ping_unhash, 1001 .get_port = ping_get_port, 1002 .obj_size = sizeof(struct inet_sock), 1003}; 1004EXPORT_SYMBOL(ping_prot); 1005 1006#ifdef CONFIG_PROC_FS 1007 1008static struct sock *ping_get_first(struct seq_file *seq, int start) 1009{ 1010 struct sock *sk; 1011 struct ping_iter_state *state = seq->private; 1012 struct net *net = seq_file_net(seq); 1013 1014 for (state->bucket = start; state->bucket < PING_HTABLE_SIZE; 1015 ++state->bucket) { 1016 struct hlist_nulls_node *node; 1017 struct hlist_nulls_head *hslot; 1018 1019 hslot = &ping_table.hash[state->bucket]; 1020 1021 if (hlist_nulls_empty(hslot)) 1022 continue; 1023 1024 sk_nulls_for_each(sk, node, hslot) { 1025 if (net_eq(sock_net(sk), net) && 1026 sk->sk_family == state->family) 1027 goto found; 1028 } 1029 } 1030 sk = NULL; 1031found: 1032 return sk; 1033} 1034 1035static struct sock *ping_get_next(struct seq_file *seq, struct sock *sk) 1036{ 1037 struct ping_iter_state *state = seq->private; 1038 struct net *net = seq_file_net(seq); 1039 1040 do { 1041 sk = sk_nulls_next(sk); 1042 } while (sk && (!net_eq(sock_net(sk), net))); 1043 1044 if (!sk) 1045 return ping_get_first(seq, state->bucket + 1); 1046 return sk; 1047} 1048 1049static struct sock *ping_get_idx(struct seq_file *seq, loff_t pos) 1050{ 1051 struct sock *sk = ping_get_first(seq, 0); 1052 1053 if (sk) 1054 while (pos && (sk = ping_get_next(seq, sk)) != NULL) 1055 --pos; 1056 return pos ? NULL : sk; 1057} 1058 1059void *ping_seq_start(struct seq_file *seq, loff_t *pos, sa_family_t family) 1060{ 1061 struct ping_iter_state *state = seq->private; 1062 state->bucket = 0; 1063 state->family = family; 1064 1065 read_lock_bh(&ping_table.lock); 1066 1067 return *pos ? ping_get_idx(seq, *pos-1) : SEQ_START_TOKEN; 1068} 1069EXPORT_SYMBOL_GPL(ping_seq_start); 1070 1071static void *ping_v4_seq_start(struct seq_file *seq, loff_t *pos) 1072{ 1073 return ping_seq_start(seq, pos, AF_INET); 1074} 1075 1076void *ping_seq_next(struct seq_file *seq, void *v, loff_t *pos) 1077{ 1078 struct sock *sk; 1079 1080 if (v == SEQ_START_TOKEN) 1081 sk = ping_get_idx(seq, 0); 1082 else 1083 sk = ping_get_next(seq, v); 1084 1085 ++*pos; 1086 return sk; 1087} 1088EXPORT_SYMBOL_GPL(ping_seq_next); 1089 1090void ping_seq_stop(struct seq_file *seq, void *v) 1091{ 1092 read_unlock_bh(&ping_table.lock); 1093} 1094EXPORT_SYMBOL_GPL(ping_seq_stop); 1095 1096static void ping_v4_format_sock(struct sock *sp, struct seq_file *f, 1097 int bucket) 1098{ 1099 struct inet_sock *inet = inet_sk(sp); 1100 __be32 dest = inet->inet_daddr; 1101 __be32 src = inet->inet_rcv_saddr; 1102 __u16 destp = ntohs(inet->inet_dport); 1103 __u16 srcp = ntohs(inet->inet_sport); 1104 1105 seq_printf(f, "%5d: %08X:%04X %08X:%04X" 1106 " %02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %d", 1107 bucket, src, srcp, dest, destp, sp->sk_state, 1108 sk_wmem_alloc_get(sp), 1109 sk_rmem_alloc_get(sp), 1110 0, 0L, 0, 1111 from_kuid_munged(seq_user_ns(f), sock_i_uid(sp)), 1112 0, sock_i_ino(sp), 1113 atomic_read(&sp->sk_refcnt), sp, 1114 atomic_read(&sp->sk_drops)); 1115} 1116 1117static int ping_v4_seq_show(struct seq_file *seq, void *v) 1118{ 1119 seq_setwidth(seq, 127); 1120 if (v == SEQ_START_TOKEN) 1121 seq_puts(seq, " sl local_address rem_address st tx_queue " 1122 "rx_queue tr tm->when retrnsmt uid timeout " 1123 "inode ref pointer drops"); 1124 else { 1125 struct ping_iter_state *state = seq->private; 1126 1127 ping_v4_format_sock(v, seq, state->bucket); 1128 } 1129 seq_pad(seq, '\n'); 1130 return 0; 1131} 1132 1133static const struct seq_operations ping_v4_seq_ops = { 1134 .show = ping_v4_seq_show, 1135 .start = ping_v4_seq_start, 1136 .next = ping_seq_next, 1137 .stop = ping_seq_stop, 1138}; 1139 1140static int ping_seq_open(struct inode *inode, struct file *file) 1141{ 1142 struct ping_seq_afinfo *afinfo = PDE_DATA(inode); 1143 return seq_open_net(inode, file, &afinfo->seq_ops, 1144 sizeof(struct ping_iter_state)); 1145} 1146 1147const struct file_operations ping_seq_fops = { 1148 .open = ping_seq_open, 1149 .read = seq_read, 1150 .llseek = seq_lseek, 1151 .release = seq_release_net, 1152}; 1153EXPORT_SYMBOL_GPL(ping_seq_fops); 1154 1155static struct ping_seq_afinfo ping_v4_seq_afinfo = { 1156 .name = "icmp", 1157 .family = AF_INET, 1158 .seq_fops = &ping_seq_fops, 1159 .seq_ops = { 1160 .start = ping_v4_seq_start, 1161 .show = ping_v4_seq_show, 1162 .next = ping_seq_next, 1163 .stop = ping_seq_stop, 1164 }, 1165}; 1166 1167int ping_proc_register(struct net *net, struct ping_seq_afinfo *afinfo) 1168{ 1169 struct proc_dir_entry *p; 1170 p = proc_create_data(afinfo->name, S_IRUGO, net->proc_net, 1171 afinfo->seq_fops, afinfo); 1172 if (!p) 1173 return -ENOMEM; 1174 return 0; 1175} 1176EXPORT_SYMBOL_GPL(ping_proc_register); 1177 1178void ping_proc_unregister(struct net *net, struct ping_seq_afinfo *afinfo) 1179{ 1180 remove_proc_entry(afinfo->name, net->proc_net); 1181} 1182EXPORT_SYMBOL_GPL(ping_proc_unregister); 1183 1184static int __net_init ping_v4_proc_init_net(struct net *net) 1185{ 1186 return ping_proc_register(net, &ping_v4_seq_afinfo); 1187} 1188 1189static void __net_exit ping_v4_proc_exit_net(struct net *net) 1190{ 1191 ping_proc_unregister(net, &ping_v4_seq_afinfo); 1192} 1193 1194static struct pernet_operations ping_v4_net_ops = { 1195 .init = ping_v4_proc_init_net, 1196 .exit = ping_v4_proc_exit_net, 1197}; 1198 1199int __init ping_proc_init(void) 1200{ 1201 return register_pernet_subsys(&ping_v4_net_ops); 1202} 1203 1204void ping_proc_exit(void) 1205{ 1206 unregister_pernet_subsys(&ping_v4_net_ops); 1207} 1208 1209#endif 1210 1211void __init ping_init(void) 1212{ 1213 int i; 1214 1215 for (i = 0; i < PING_HTABLE_SIZE; i++) 1216 INIT_HLIST_NULLS_HEAD(&ping_table.hash[i], i); 1217 rwlock_init(&ping_table.lock); 1218} 1219