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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * INET An implementation of the TCP/IP protocol suite for the LINUX
4 * operating system. INET is implemented using the BSD Socket
5 * interface as the means of communication with the user level.
6 *
7 * "Ping" sockets
8 *
9 * Based on ipv4/udp.c code.
10 *
11 * Authors: Vasiliy Kulikov / Openwall (for Linux 2.6),
12 * Pavel Kankovsky (for Linux 2.4.32)
13 *
14 * Pavel gave all rights to bugs to Vasiliy,
15 * none of the bugs are Pavel's now.
16 */
17
18#include <linux/uaccess.h>
19#include <linux/types.h>
20#include <linux/fcntl.h>
21#include <linux/socket.h>
22#include <linux/sockios.h>
23#include <linux/in.h>
24#include <linux/errno.h>
25#include <linux/timer.h>
26#include <linux/mm.h>
27#include <linux/inet.h>
28#include <linux/netdevice.h>
29#include <net/snmp.h>
30#include <net/ip.h>
31#include <net/icmp.h>
32#include <net/protocol.h>
33#include <linux/skbuff.h>
34#include <linux/proc_fs.h>
35#include <linux/export.h>
36#include <linux/bpf-cgroup.h>
37#include <net/sock.h>
38#include <net/ping.h>
39#include <net/udp.h>
40#include <net/route.h>
41#include <net/inet_common.h>
42#include <net/checksum.h>
43
44#if IS_ENABLED(CONFIG_IPV6)
45#include <linux/in6.h>
46#include <linux/icmpv6.h>
47#include <net/addrconf.h>
48#include <net/ipv6.h>
49#include <net/transp_v6.h>
50#endif
51
52struct ping_table {
53 struct hlist_head hash[PING_HTABLE_SIZE];
54 spinlock_t lock;
55};
56
57static struct ping_table ping_table;
58struct pingv6_ops pingv6_ops;
59EXPORT_SYMBOL_GPL(pingv6_ops);
60
61static u16 ping_port_rover;
62
63static inline u32 ping_hashfn(const struct net *net, u32 num, u32 mask)
64{
65 u32 res = (num + net_hash_mix(net)) & mask;
66
67 pr_debug("hash(%u) = %u\n", num, res);
68 return res;
69}
70EXPORT_SYMBOL_GPL(ping_hash);
71
72static inline struct hlist_head *ping_hashslot(struct ping_table *table,
73 struct net *net, unsigned int num)
74{
75 return &table->hash[ping_hashfn(net, num, PING_HTABLE_MASK)];
76}
77
78int ping_get_port(struct sock *sk, unsigned short ident)
79{
80 struct inet_sock *isk, *isk2;
81 struct hlist_head *hlist;
82 struct sock *sk2 = NULL;
83
84 isk = inet_sk(sk);
85 spin_lock(&ping_table.lock);
86 if (ident == 0) {
87 u32 i;
88 u16 result = ping_port_rover + 1;
89
90 for (i = 0; i < (1L << 16); i++, result++) {
91 if (!result)
92 result++; /* avoid zero */
93 hlist = ping_hashslot(&ping_table, sock_net(sk),
94 result);
95 sk_for_each(sk2, hlist) {
96 isk2 = inet_sk(sk2);
97
98 if (isk2->inet_num == result)
99 goto next_port;
100 }
101
102 /* found */
103 ping_port_rover = ident = result;
104 break;
105next_port:
106 ;
107 }
108 if (i >= (1L << 16))
109 goto fail;
110 } else {
111 hlist = ping_hashslot(&ping_table, sock_net(sk), ident);
112 sk_for_each(sk2, hlist) {
113 isk2 = inet_sk(sk2);
114
115 /* BUG? Why is this reuse and not reuseaddr? ping.c
116 * doesn't turn off SO_REUSEADDR, and it doesn't expect
117 * that other ping processes can steal its packets.
118 */
119 if ((isk2->inet_num == ident) &&
120 (sk2 != sk) &&
121 (!sk2->sk_reuse || !sk->sk_reuse))
122 goto fail;
123 }
124 }
125
126 pr_debug("found port/ident = %d\n", ident);
127 isk->inet_num = ident;
128 if (sk_unhashed(sk)) {
129 pr_debug("was not hashed\n");
130 sk_add_node_rcu(sk, hlist);
131 sock_set_flag(sk, SOCK_RCU_FREE);
132 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
133 }
134 spin_unlock(&ping_table.lock);
135 return 0;
136
137fail:
138 spin_unlock(&ping_table.lock);
139 return -EADDRINUSE;
140}
141EXPORT_SYMBOL_GPL(ping_get_port);
142
143int ping_hash(struct sock *sk)
144{
145 pr_debug("ping_hash(sk->port=%u)\n", inet_sk(sk)->inet_num);
146 BUG(); /* "Please do not press this button again." */
147
148 return 0;
149}
150
151void ping_unhash(struct sock *sk)
152{
153 struct inet_sock *isk = inet_sk(sk);
154
155 pr_debug("ping_unhash(isk=%p,isk->num=%u)\n", isk, isk->inet_num);
156 spin_lock(&ping_table.lock);
157 if (sk_del_node_init_rcu(sk)) {
158 isk->inet_num = 0;
159 isk->inet_sport = 0;
160 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
161 }
162 spin_unlock(&ping_table.lock);
163}
164EXPORT_SYMBOL_GPL(ping_unhash);
165
166/* Called under rcu_read_lock() */
167static struct sock *ping_lookup(struct net *net, struct sk_buff *skb, u16 ident)
168{
169 struct hlist_head *hslot = ping_hashslot(&ping_table, net, ident);
170 struct sock *sk = NULL;
171 struct inet_sock *isk;
172 int dif, sdif;
173
174 if (skb->protocol == htons(ETH_P_IP)) {
175 dif = inet_iif(skb);
176 sdif = inet_sdif(skb);
177 pr_debug("try to find: num = %d, daddr = %pI4, dif = %d\n",
178 (int)ident, &ip_hdr(skb)->daddr, dif);
179#if IS_ENABLED(CONFIG_IPV6)
180 } else if (skb->protocol == htons(ETH_P_IPV6)) {
181 dif = inet6_iif(skb);
182 sdif = inet6_sdif(skb);
183 pr_debug("try to find: num = %d, daddr = %pI6c, dif = %d\n",
184 (int)ident, &ipv6_hdr(skb)->daddr, dif);
185#endif
186 } else {
187 return NULL;
188 }
189
190 sk_for_each_rcu(sk, 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 } else {
221 continue;
222 }
223
224 if (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif &&
225 sk->sk_bound_dev_if != sdif)
226 continue;
227
228 goto exit;
229 }
230
231 sk = NULL;
232exit:
233
234 return sk;
235}
236
237static void inet_get_ping_group_range_net(struct net *net, kgid_t *low,
238 kgid_t *high)
239{
240 kgid_t *data = net->ipv4.ping_group_range.range;
241 unsigned int seq;
242
243 do {
244 seq = read_seqbegin(&net->ipv4.ping_group_range.lock);
245
246 *low = data[0];
247 *high = data[1];
248 } while (read_seqretry(&net->ipv4.ping_group_range.lock, seq));
249}
250
251
252int ping_init_sock(struct sock *sk)
253{
254 struct net *net = sock_net(sk);
255 kgid_t group = current_egid();
256 struct group_info *group_info;
257 int i;
258 kgid_t low, high;
259 int ret = 0;
260
261 if (sk->sk_family == AF_INET6)
262 sk->sk_ipv6only = 1;
263
264 inet_get_ping_group_range_net(net, &low, &high);
265 if (gid_lte(low, group) && gid_lte(group, high))
266 return 0;
267
268 group_info = get_current_groups();
269 for (i = 0; i < group_info->ngroups; i++) {
270 kgid_t gid = group_info->gid[i];
271
272 if (gid_lte(low, gid) && gid_lte(gid, high))
273 goto out_release_group;
274 }
275
276 ret = -EACCES;
277
278out_release_group:
279 put_group_info(group_info);
280 return ret;
281}
282EXPORT_SYMBOL_GPL(ping_init_sock);
283
284void ping_close(struct sock *sk, long timeout)
285{
286 pr_debug("ping_close(sk=%p,sk->num=%u)\n",
287 inet_sk(sk), inet_sk(sk)->inet_num);
288 pr_debug("isk->refcnt = %d\n", refcount_read(&sk->sk_refcnt));
289
290 sk_common_release(sk);
291}
292EXPORT_SYMBOL_GPL(ping_close);
293
294static int ping_pre_connect(struct sock *sk, struct sockaddr *uaddr,
295 int addr_len)
296{
297 /* This check is replicated from __ip4_datagram_connect() and
298 * intended to prevent BPF program called below from accessing bytes
299 * that are out of the bound specified by user in addr_len.
300 */
301 if (addr_len < sizeof(struct sockaddr_in))
302 return -EINVAL;
303
304 return BPF_CGROUP_RUN_PROG_INET4_CONNECT_LOCK(sk, uaddr, &addr_len);
305}
306
307/* Checks the bind address and possibly modifies sk->sk_bound_dev_if. */
308static int ping_check_bind_addr(struct sock *sk, struct inet_sock *isk,
309 struct sockaddr *uaddr, int addr_len)
310{
311 struct net *net = sock_net(sk);
312 if (sk->sk_family == AF_INET) {
313 struct sockaddr_in *addr = (struct sockaddr_in *) uaddr;
314 u32 tb_id = RT_TABLE_LOCAL;
315 int chk_addr_ret;
316
317 if (addr_len < sizeof(*addr))
318 return -EINVAL;
319
320 if (addr->sin_family != AF_INET &&
321 !(addr->sin_family == AF_UNSPEC &&
322 addr->sin_addr.s_addr == htonl(INADDR_ANY)))
323 return -EAFNOSUPPORT;
324
325 pr_debug("ping_check_bind_addr(sk=%p,addr=%pI4,port=%d)\n",
326 sk, &addr->sin_addr.s_addr, ntohs(addr->sin_port));
327
328 if (addr->sin_addr.s_addr == htonl(INADDR_ANY))
329 return 0;
330
331 tb_id = l3mdev_fib_table_by_index(net, sk->sk_bound_dev_if) ? : tb_id;
332 chk_addr_ret = inet_addr_type_table(net, addr->sin_addr.s_addr, tb_id);
333
334 if (chk_addr_ret == RTN_MULTICAST ||
335 chk_addr_ret == RTN_BROADCAST ||
336 (chk_addr_ret != RTN_LOCAL &&
337 !inet_can_nonlocal_bind(net, isk)))
338 return -EADDRNOTAVAIL;
339
340#if IS_ENABLED(CONFIG_IPV6)
341 } else if (sk->sk_family == AF_INET6) {
342 struct sockaddr_in6 *addr = (struct sockaddr_in6 *) uaddr;
343 int addr_type, scoped, has_addr;
344 struct net_device *dev = NULL;
345
346 if (addr_len < sizeof(*addr))
347 return -EINVAL;
348
349 if (addr->sin6_family != AF_INET6)
350 return -EAFNOSUPPORT;
351
352 pr_debug("ping_check_bind_addr(sk=%p,addr=%pI6c,port=%d)\n",
353 sk, addr->sin6_addr.s6_addr, ntohs(addr->sin6_port));
354
355 addr_type = ipv6_addr_type(&addr->sin6_addr);
356 scoped = __ipv6_addr_needs_scope_id(addr_type);
357 if ((addr_type != IPV6_ADDR_ANY &&
358 !(addr_type & IPV6_ADDR_UNICAST)) ||
359 (scoped && !addr->sin6_scope_id))
360 return -EINVAL;
361
362 rcu_read_lock();
363 if (addr->sin6_scope_id) {
364 dev = dev_get_by_index_rcu(net, addr->sin6_scope_id);
365 if (!dev) {
366 rcu_read_unlock();
367 return -ENODEV;
368 }
369 }
370
371 if (!dev && sk->sk_bound_dev_if) {
372 dev = dev_get_by_index_rcu(net, sk->sk_bound_dev_if);
373 if (!dev) {
374 rcu_read_unlock();
375 return -ENODEV;
376 }
377 }
378 has_addr = pingv6_ops.ipv6_chk_addr(net, &addr->sin6_addr, dev,
379 scoped);
380 rcu_read_unlock();
381
382 if (!(ipv6_can_nonlocal_bind(net, isk) || has_addr ||
383 addr_type == IPV6_ADDR_ANY))
384 return -EADDRNOTAVAIL;
385
386 if (scoped)
387 sk->sk_bound_dev_if = addr->sin6_scope_id;
388#endif
389 } else {
390 return -EAFNOSUPPORT;
391 }
392 return 0;
393}
394
395static void ping_set_saddr(struct sock *sk, struct sockaddr *saddr)
396{
397 if (saddr->sa_family == AF_INET) {
398 struct inet_sock *isk = inet_sk(sk);
399 struct sockaddr_in *addr = (struct sockaddr_in *) saddr;
400 isk->inet_rcv_saddr = isk->inet_saddr = addr->sin_addr.s_addr;
401#if IS_ENABLED(CONFIG_IPV6)
402 } else if (saddr->sa_family == AF_INET6) {
403 struct sockaddr_in6 *addr = (struct sockaddr_in6 *) saddr;
404 struct ipv6_pinfo *np = inet6_sk(sk);
405 sk->sk_v6_rcv_saddr = np->saddr = addr->sin6_addr;
406#endif
407 }
408}
409
410/*
411 * We need our own bind because there are no privileged id's == local ports.
412 * Moreover, we don't allow binding to multi- and broadcast addresses.
413 */
414
415int ping_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len)
416{
417 struct inet_sock *isk = inet_sk(sk);
418 unsigned short snum;
419 int err;
420 int dif = sk->sk_bound_dev_if;
421
422 err = ping_check_bind_addr(sk, isk, uaddr, addr_len);
423 if (err)
424 return err;
425
426 lock_sock(sk);
427
428 err = -EINVAL;
429 if (isk->inet_num != 0)
430 goto out;
431
432 err = -EADDRINUSE;
433 snum = ntohs(((struct sockaddr_in *)uaddr)->sin_port);
434 if (ping_get_port(sk, snum) != 0) {
435 /* Restore possibly modified sk->sk_bound_dev_if by ping_check_bind_addr(). */
436 sk->sk_bound_dev_if = dif;
437 goto out;
438 }
439 ping_set_saddr(sk, uaddr);
440
441 pr_debug("after bind(): num = %hu, dif = %d\n",
442 isk->inet_num,
443 sk->sk_bound_dev_if);
444
445 err = 0;
446 if (sk->sk_family == AF_INET && isk->inet_rcv_saddr)
447 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
448#if IS_ENABLED(CONFIG_IPV6)
449 if (sk->sk_family == AF_INET6 && !ipv6_addr_any(&sk->sk_v6_rcv_saddr))
450 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
451#endif
452
453 if (snum)
454 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
455 isk->inet_sport = htons(isk->inet_num);
456 isk->inet_daddr = 0;
457 isk->inet_dport = 0;
458
459#if IS_ENABLED(CONFIG_IPV6)
460 if (sk->sk_family == AF_INET6)
461 memset(&sk->sk_v6_daddr, 0, sizeof(sk->sk_v6_daddr));
462#endif
463
464 sk_dst_reset(sk);
465out:
466 release_sock(sk);
467 pr_debug("ping_v4_bind -> %d\n", err);
468 return err;
469}
470EXPORT_SYMBOL_GPL(ping_bind);
471
472/*
473 * Is this a supported type of ICMP message?
474 */
475
476static inline int ping_supported(int family, int type, int code)
477{
478 return (family == AF_INET && type == ICMP_ECHO && code == 0) ||
479 (family == AF_INET && type == ICMP_EXT_ECHO && code == 0) ||
480 (family == AF_INET6 && type == ICMPV6_ECHO_REQUEST && code == 0) ||
481 (family == AF_INET6 && type == ICMPV6_EXT_ECHO_REQUEST && code == 0);
482}
483
484/*
485 * This routine is called by the ICMP module when it gets some
486 * sort of error condition.
487 */
488
489void ping_err(struct sk_buff *skb, int offset, u32 info)
490{
491 int family;
492 struct icmphdr *icmph;
493 struct inet_sock *inet_sock;
494 int type;
495 int code;
496 struct net *net = dev_net(skb->dev);
497 struct sock *sk;
498 int harderr;
499 int err;
500
501 if (skb->protocol == htons(ETH_P_IP)) {
502 family = AF_INET;
503 type = icmp_hdr(skb)->type;
504 code = icmp_hdr(skb)->code;
505 icmph = (struct icmphdr *)(skb->data + offset);
506 } else if (skb->protocol == htons(ETH_P_IPV6)) {
507 family = AF_INET6;
508 type = icmp6_hdr(skb)->icmp6_type;
509 code = icmp6_hdr(skb)->icmp6_code;
510 icmph = (struct icmphdr *) (skb->data + offset);
511 } else {
512 BUG();
513 }
514
515 /* We assume the packet has already been checked by icmp_unreach */
516
517 if (!ping_supported(family, icmph->type, icmph->code))
518 return;
519
520 pr_debug("ping_err(proto=0x%x,type=%d,code=%d,id=%04x,seq=%04x)\n",
521 skb->protocol, type, code, ntohs(icmph->un.echo.id),
522 ntohs(icmph->un.echo.sequence));
523
524 sk = ping_lookup(net, skb, ntohs(icmph->un.echo.id));
525 if (!sk) {
526 pr_debug("no socket, dropping\n");
527 return; /* No socket for error */
528 }
529 pr_debug("err on socket %p\n", sk);
530
531 err = 0;
532 harderr = 0;
533 inet_sock = inet_sk(sk);
534
535 if (skb->protocol == htons(ETH_P_IP)) {
536 switch (type) {
537 default:
538 case ICMP_TIME_EXCEEDED:
539 err = EHOSTUNREACH;
540 break;
541 case ICMP_SOURCE_QUENCH:
542 /* This is not a real error but ping wants to see it.
543 * Report it with some fake errno.
544 */
545 err = EREMOTEIO;
546 break;
547 case ICMP_PARAMETERPROB:
548 err = EPROTO;
549 harderr = 1;
550 break;
551 case ICMP_DEST_UNREACH:
552 if (code == ICMP_FRAG_NEEDED) { /* Path MTU discovery */
553 ipv4_sk_update_pmtu(skb, sk, info);
554 if (READ_ONCE(inet_sock->pmtudisc) != IP_PMTUDISC_DONT) {
555 err = EMSGSIZE;
556 harderr = 1;
557 break;
558 }
559 goto out;
560 }
561 err = EHOSTUNREACH;
562 if (code <= NR_ICMP_UNREACH) {
563 harderr = icmp_err_convert[code].fatal;
564 err = icmp_err_convert[code].errno;
565 }
566 break;
567 case ICMP_REDIRECT:
568 /* See ICMP_SOURCE_QUENCH */
569 ipv4_sk_redirect(skb, sk);
570 err = EREMOTEIO;
571 break;
572 }
573#if IS_ENABLED(CONFIG_IPV6)
574 } else if (skb->protocol == htons(ETH_P_IPV6)) {
575 harderr = pingv6_ops.icmpv6_err_convert(type, code, &err);
576#endif
577 }
578
579 /*
580 * RFC1122: OK. Passes ICMP errors back to application, as per
581 * 4.1.3.3.
582 */
583 if ((family == AF_INET && !inet_test_bit(RECVERR, sk)) ||
584 (family == AF_INET6 && !inet6_test_bit(RECVERR6, sk))) {
585 if (!harderr || sk->sk_state != TCP_ESTABLISHED)
586 goto out;
587 } else {
588 if (family == AF_INET) {
589 ip_icmp_error(sk, skb, err, 0 /* no remote port */,
590 info, (u8 *)icmph);
591#if IS_ENABLED(CONFIG_IPV6)
592 } else if (family == AF_INET6) {
593 pingv6_ops.ipv6_icmp_error(sk, skb, err, 0,
594 info, (u8 *)icmph);
595#endif
596 }
597 }
598 sk->sk_err = err;
599 sk_error_report(sk);
600out:
601 return;
602}
603EXPORT_SYMBOL_GPL(ping_err);
604
605/*
606 * Copy and checksum an ICMP Echo packet from user space into a buffer
607 * starting from the payload.
608 */
609
610int ping_getfrag(void *from, char *to,
611 int offset, int fraglen, int odd, struct sk_buff *skb)
612{
613 struct pingfakehdr *pfh = from;
614
615 if (!csum_and_copy_from_iter_full(to, fraglen, &pfh->wcheck,
616 &pfh->msg->msg_iter))
617 return -EFAULT;
618
619#if IS_ENABLED(CONFIG_IPV6)
620 /* For IPv6, checksum each skb as we go along, as expected by
621 * icmpv6_push_pending_frames. For IPv4, accumulate the checksum in
622 * wcheck, it will be finalized in ping_v4_push_pending_frames.
623 */
624 if (pfh->family == AF_INET6) {
625 skb->csum = csum_block_add(skb->csum, pfh->wcheck, odd);
626 skb->ip_summed = CHECKSUM_NONE;
627 pfh->wcheck = 0;
628 }
629#endif
630
631 return 0;
632}
633EXPORT_SYMBOL_GPL(ping_getfrag);
634
635static int ping_v4_push_pending_frames(struct sock *sk, struct pingfakehdr *pfh,
636 struct flowi4 *fl4)
637{
638 struct sk_buff *skb = skb_peek(&sk->sk_write_queue);
639
640 if (!skb)
641 return 0;
642 pfh->wcheck = csum_partial((char *)&pfh->icmph,
643 sizeof(struct icmphdr), pfh->wcheck);
644 pfh->icmph.checksum = csum_fold(pfh->wcheck);
645 memcpy(icmp_hdr(skb), &pfh->icmph, sizeof(struct icmphdr));
646 skb->ip_summed = CHECKSUM_NONE;
647 return ip_push_pending_frames(sk, fl4);
648}
649
650int ping_common_sendmsg(int family, struct msghdr *msg, size_t len,
651 void *user_icmph, size_t icmph_len)
652{
653 u8 type, code;
654
655 if (len > 0xFFFF)
656 return -EMSGSIZE;
657
658 /* Must have at least a full ICMP header. */
659 if (len < icmph_len)
660 return -EINVAL;
661
662 /*
663 * Check the flags.
664 */
665
666 /* Mirror BSD error message compatibility */
667 if (msg->msg_flags & MSG_OOB)
668 return -EOPNOTSUPP;
669
670 /*
671 * Fetch the ICMP header provided by the userland.
672 * iovec is modified! The ICMP header is consumed.
673 */
674 if (memcpy_from_msg(user_icmph, msg, icmph_len))
675 return -EFAULT;
676
677 if (family == AF_INET) {
678 type = ((struct icmphdr *) user_icmph)->type;
679 code = ((struct icmphdr *) user_icmph)->code;
680#if IS_ENABLED(CONFIG_IPV6)
681 } else if (family == AF_INET6) {
682 type = ((struct icmp6hdr *) user_icmph)->icmp6_type;
683 code = ((struct icmp6hdr *) user_icmph)->icmp6_code;
684#endif
685 } else {
686 BUG();
687 }
688
689 if (!ping_supported(family, type, code))
690 return -EINVAL;
691
692 return 0;
693}
694EXPORT_SYMBOL_GPL(ping_common_sendmsg);
695
696static int ping_v4_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
697{
698 struct net *net = sock_net(sk);
699 struct flowi4 fl4;
700 struct inet_sock *inet = inet_sk(sk);
701 struct ipcm_cookie ipc;
702 struct icmphdr user_icmph;
703 struct pingfakehdr pfh;
704 struct rtable *rt = NULL;
705 struct ip_options_data opt_copy;
706 int free = 0;
707 __be32 saddr, daddr, faddr;
708 u8 tos, scope;
709 int err;
710
711 pr_debug("ping_v4_sendmsg(sk=%p,sk->num=%u)\n", inet, inet->inet_num);
712
713 err = ping_common_sendmsg(AF_INET, msg, len, &user_icmph,
714 sizeof(user_icmph));
715 if (err)
716 return err;
717
718 /*
719 * Get and verify the address.
720 */
721
722 if (msg->msg_name) {
723 DECLARE_SOCKADDR(struct sockaddr_in *, usin, msg->msg_name);
724 if (msg->msg_namelen < sizeof(*usin))
725 return -EINVAL;
726 if (usin->sin_family != AF_INET)
727 return -EAFNOSUPPORT;
728 daddr = usin->sin_addr.s_addr;
729 /* no remote port */
730 } else {
731 if (sk->sk_state != TCP_ESTABLISHED)
732 return -EDESTADDRREQ;
733 daddr = inet->inet_daddr;
734 /* no remote port */
735 }
736
737 ipcm_init_sk(&ipc, inet);
738
739 if (msg->msg_controllen) {
740 err = ip_cmsg_send(sk, msg, &ipc, false);
741 if (unlikely(err)) {
742 kfree(ipc.opt);
743 return err;
744 }
745 if (ipc.opt)
746 free = 1;
747 }
748 if (!ipc.opt) {
749 struct ip_options_rcu *inet_opt;
750
751 rcu_read_lock();
752 inet_opt = rcu_dereference(inet->inet_opt);
753 if (inet_opt) {
754 memcpy(&opt_copy, inet_opt,
755 sizeof(*inet_opt) + inet_opt->opt.optlen);
756 ipc.opt = &opt_copy.opt;
757 }
758 rcu_read_unlock();
759 }
760
761 saddr = ipc.addr;
762 ipc.addr = faddr = daddr;
763
764 if (ipc.opt && ipc.opt->opt.srr) {
765 if (!daddr) {
766 err = -EINVAL;
767 goto out_free;
768 }
769 faddr = ipc.opt->opt.faddr;
770 }
771 tos = get_rttos(&ipc, inet);
772 scope = ip_sendmsg_scope(inet, &ipc, msg);
773
774 if (ipv4_is_multicast(daddr)) {
775 if (!ipc.oif || netif_index_is_l3_master(sock_net(sk), ipc.oif))
776 ipc.oif = READ_ONCE(inet->mc_index);
777 if (!saddr)
778 saddr = READ_ONCE(inet->mc_addr);
779 } else if (!ipc.oif)
780 ipc.oif = READ_ONCE(inet->uc_index);
781
782 flowi4_init_output(&fl4, ipc.oif, ipc.sockc.mark, tos, scope,
783 sk->sk_protocol, inet_sk_flowi_flags(sk), faddr,
784 saddr, 0, 0, sk->sk_uid);
785
786 fl4.fl4_icmp_type = user_icmph.type;
787 fl4.fl4_icmp_code = user_icmph.code;
788
789 security_sk_classify_flow(sk, flowi4_to_flowi_common(&fl4));
790 rt = ip_route_output_flow(net, &fl4, sk);
791 if (IS_ERR(rt)) {
792 err = PTR_ERR(rt);
793 rt = NULL;
794 if (err == -ENETUNREACH)
795 IP_INC_STATS(net, IPSTATS_MIB_OUTNOROUTES);
796 goto out;
797 }
798
799 err = -EACCES;
800 if ((rt->rt_flags & RTCF_BROADCAST) &&
801 !sock_flag(sk, SOCK_BROADCAST))
802 goto out;
803
804 if (msg->msg_flags & MSG_CONFIRM)
805 goto do_confirm;
806back_from_confirm:
807
808 if (!ipc.addr)
809 ipc.addr = fl4.daddr;
810
811 lock_sock(sk);
812
813 pfh.icmph.type = user_icmph.type; /* already checked */
814 pfh.icmph.code = user_icmph.code; /* ditto */
815 pfh.icmph.checksum = 0;
816 pfh.icmph.un.echo.id = inet->inet_sport;
817 pfh.icmph.un.echo.sequence = user_icmph.un.echo.sequence;
818 pfh.msg = msg;
819 pfh.wcheck = 0;
820 pfh.family = AF_INET;
821
822 err = ip_append_data(sk, &fl4, ping_getfrag, &pfh, len,
823 sizeof(struct icmphdr), &ipc, &rt,
824 msg->msg_flags);
825 if (err)
826 ip_flush_pending_frames(sk);
827 else
828 err = ping_v4_push_pending_frames(sk, &pfh, &fl4);
829 release_sock(sk);
830
831out:
832 ip_rt_put(rt);
833out_free:
834 if (free)
835 kfree(ipc.opt);
836 if (!err) {
837 icmp_out_count(sock_net(sk), user_icmph.type);
838 return len;
839 }
840 return err;
841
842do_confirm:
843 if (msg->msg_flags & MSG_PROBE)
844 dst_confirm_neigh(&rt->dst, &fl4.daddr);
845 if (!(msg->msg_flags & MSG_PROBE) || len)
846 goto back_from_confirm;
847 err = 0;
848 goto out;
849}
850
851int ping_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int flags,
852 int *addr_len)
853{
854 struct inet_sock *isk = inet_sk(sk);
855 int family = sk->sk_family;
856 struct sk_buff *skb;
857 int copied, err;
858
859 pr_debug("ping_recvmsg(sk=%p,sk->num=%u)\n", isk, isk->inet_num);
860
861 err = -EOPNOTSUPP;
862 if (flags & MSG_OOB)
863 goto out;
864
865 if (flags & MSG_ERRQUEUE)
866 return inet_recv_error(sk, msg, len, addr_len);
867
868 skb = skb_recv_datagram(sk, flags, &err);
869 if (!skb)
870 goto out;
871
872 copied = skb->len;
873 if (copied > len) {
874 msg->msg_flags |= MSG_TRUNC;
875 copied = len;
876 }
877
878 /* Don't bother checking the checksum */
879 err = skb_copy_datagram_msg(skb, 0, msg, copied);
880 if (err)
881 goto done;
882
883 sock_recv_timestamp(msg, sk, skb);
884
885 /* Copy the address and add cmsg data. */
886 if (family == AF_INET) {
887 DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name);
888
889 if (sin) {
890 sin->sin_family = AF_INET;
891 sin->sin_port = 0 /* skb->h.uh->source */;
892 sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
893 memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
894 *addr_len = sizeof(*sin);
895 }
896
897 if (inet_cmsg_flags(isk))
898 ip_cmsg_recv(msg, skb);
899
900#if IS_ENABLED(CONFIG_IPV6)
901 } else if (family == AF_INET6) {
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 (inet6_test_bit(SNDFLOW, sk))
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) &&
924 inet_cmsg_flags(isk))
925 ip_cmsg_recv(msg, skb);
926#endif
927 } else {
928 BUG();
929 }
930
931 err = copied;
932
933done:
934 skb_free_datagram(sk, skb);
935out:
936 pr_debug("ping_recvmsg -> %d\n", err);
937 return err;
938}
939EXPORT_SYMBOL_GPL(ping_recvmsg);
940
941static enum skb_drop_reason __ping_queue_rcv_skb(struct sock *sk,
942 struct sk_buff *skb)
943{
944 enum skb_drop_reason reason;
945
946 pr_debug("ping_queue_rcv_skb(sk=%p,sk->num=%d,skb=%p)\n",
947 inet_sk(sk), inet_sk(sk)->inet_num, skb);
948 if (sock_queue_rcv_skb_reason(sk, skb, &reason) < 0) {
949 sk_skb_reason_drop(sk, skb, reason);
950 pr_debug("ping_queue_rcv_skb -> failed\n");
951 return reason;
952 }
953 return SKB_NOT_DROPPED_YET;
954}
955
956int ping_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
957{
958 return __ping_queue_rcv_skb(sk, skb) ? -1 : 0;
959}
960EXPORT_SYMBOL_GPL(ping_queue_rcv_skb);
961
962
963/*
964 * All we need to do is get the socket.
965 */
966
967enum skb_drop_reason ping_rcv(struct sk_buff *skb)
968{
969 enum skb_drop_reason reason = SKB_DROP_REASON_NO_SOCKET;
970 struct sock *sk;
971 struct net *net = dev_net(skb->dev);
972 struct icmphdr *icmph = icmp_hdr(skb);
973
974 /* We assume the packet has already been checked by icmp_rcv */
975
976 pr_debug("ping_rcv(skb=%p,id=%04x,seq=%04x)\n",
977 skb, ntohs(icmph->un.echo.id), ntohs(icmph->un.echo.sequence));
978
979 /* Push ICMP header back */
980 skb_push(skb, skb->data - (u8 *)icmph);
981
982 sk = ping_lookup(net, skb, ntohs(icmph->un.echo.id));
983 if (sk) {
984 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
985
986 pr_debug("rcv on socket %p\n", sk);
987 if (skb2)
988 reason = __ping_queue_rcv_skb(sk, skb2);
989 else
990 reason = SKB_DROP_REASON_NOMEM;
991 }
992
993 if (reason)
994 pr_debug("no socket, dropping\n");
995
996 return reason;
997}
998EXPORT_SYMBOL_GPL(ping_rcv);
999
1000struct proto ping_prot = {
1001 .name = "PING",
1002 .owner = THIS_MODULE,
1003 .init = ping_init_sock,
1004 .close = ping_close,
1005 .pre_connect = ping_pre_connect,
1006 .connect = ip4_datagram_connect,
1007 .disconnect = __udp_disconnect,
1008 .setsockopt = ip_setsockopt,
1009 .getsockopt = ip_getsockopt,
1010 .sendmsg = ping_v4_sendmsg,
1011 .recvmsg = ping_recvmsg,
1012 .bind = ping_bind,
1013 .backlog_rcv = ping_queue_rcv_skb,
1014 .release_cb = ip4_datagram_release_cb,
1015 .hash = ping_hash,
1016 .unhash = ping_unhash,
1017 .get_port = ping_get_port,
1018 .put_port = ping_unhash,
1019 .obj_size = sizeof(struct inet_sock),
1020};
1021EXPORT_SYMBOL(ping_prot);
1022
1023#ifdef CONFIG_PROC_FS
1024
1025static struct sock *ping_get_first(struct seq_file *seq, int start)
1026{
1027 struct sock *sk;
1028 struct ping_iter_state *state = seq->private;
1029 struct net *net = seq_file_net(seq);
1030
1031 for (state->bucket = start; state->bucket < PING_HTABLE_SIZE;
1032 ++state->bucket) {
1033 struct hlist_head *hslot;
1034
1035 hslot = &ping_table.hash[state->bucket];
1036
1037 if (hlist_empty(hslot))
1038 continue;
1039
1040 sk_for_each(sk, hslot) {
1041 if (net_eq(sock_net(sk), net) &&
1042 sk->sk_family == state->family)
1043 goto found;
1044 }
1045 }
1046 sk = NULL;
1047found:
1048 return sk;
1049}
1050
1051static struct sock *ping_get_next(struct seq_file *seq, struct sock *sk)
1052{
1053 struct ping_iter_state *state = seq->private;
1054 struct net *net = seq_file_net(seq);
1055
1056 do {
1057 sk = sk_next(sk);
1058 } while (sk && (!net_eq(sock_net(sk), net)));
1059
1060 if (!sk)
1061 return ping_get_first(seq, state->bucket + 1);
1062 return sk;
1063}
1064
1065static struct sock *ping_get_idx(struct seq_file *seq, loff_t pos)
1066{
1067 struct sock *sk = ping_get_first(seq, 0);
1068
1069 if (sk)
1070 while (pos && (sk = ping_get_next(seq, sk)) != NULL)
1071 --pos;
1072 return pos ? NULL : sk;
1073}
1074
1075void *ping_seq_start(struct seq_file *seq, loff_t *pos, sa_family_t family)
1076 __acquires(ping_table.lock)
1077{
1078 struct ping_iter_state *state = seq->private;
1079 state->bucket = 0;
1080 state->family = family;
1081
1082 spin_lock(&ping_table.lock);
1083
1084 return *pos ? ping_get_idx(seq, *pos-1) : SEQ_START_TOKEN;
1085}
1086EXPORT_SYMBOL_GPL(ping_seq_start);
1087
1088static void *ping_v4_seq_start(struct seq_file *seq, loff_t *pos)
1089{
1090 return ping_seq_start(seq, pos, AF_INET);
1091}
1092
1093void *ping_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1094{
1095 struct sock *sk;
1096
1097 if (v == SEQ_START_TOKEN)
1098 sk = ping_get_idx(seq, 0);
1099 else
1100 sk = ping_get_next(seq, v);
1101
1102 ++*pos;
1103 return sk;
1104}
1105EXPORT_SYMBOL_GPL(ping_seq_next);
1106
1107void ping_seq_stop(struct seq_file *seq, void *v)
1108 __releases(ping_table.lock)
1109{
1110 spin_unlock(&ping_table.lock);
1111}
1112EXPORT_SYMBOL_GPL(ping_seq_stop);
1113
1114static void ping_v4_format_sock(struct sock *sp, struct seq_file *f,
1115 int bucket)
1116{
1117 struct inet_sock *inet = inet_sk(sp);
1118 __be32 dest = inet->inet_daddr;
1119 __be32 src = inet->inet_rcv_saddr;
1120 __u16 destp = ntohs(inet->inet_dport);
1121 __u16 srcp = ntohs(inet->inet_sport);
1122
1123 seq_printf(f, "%5d: %08X:%04X %08X:%04X"
1124 " %02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %u",
1125 bucket, src, srcp, dest, destp, sp->sk_state,
1126 sk_wmem_alloc_get(sp),
1127 sk_rmem_alloc_get(sp),
1128 0, 0L, 0,
1129 from_kuid_munged(seq_user_ns(f), sock_i_uid(sp)),
1130 0, sock_i_ino(sp),
1131 refcount_read(&sp->sk_refcnt), sp,
1132 atomic_read(&sp->sk_drops));
1133}
1134
1135static int ping_v4_seq_show(struct seq_file *seq, void *v)
1136{
1137 seq_setwidth(seq, 127);
1138 if (v == SEQ_START_TOKEN)
1139 seq_puts(seq, " sl local_address rem_address st tx_queue "
1140 "rx_queue tr tm->when retrnsmt uid timeout "
1141 "inode ref pointer drops");
1142 else {
1143 struct ping_iter_state *state = seq->private;
1144
1145 ping_v4_format_sock(v, seq, state->bucket);
1146 }
1147 seq_pad(seq, '\n');
1148 return 0;
1149}
1150
1151static const struct seq_operations ping_v4_seq_ops = {
1152 .start = ping_v4_seq_start,
1153 .show = ping_v4_seq_show,
1154 .next = ping_seq_next,
1155 .stop = ping_seq_stop,
1156};
1157
1158static int __net_init ping_v4_proc_init_net(struct net *net)
1159{
1160 if (!proc_create_net("icmp", 0444, net->proc_net, &ping_v4_seq_ops,
1161 sizeof(struct ping_iter_state)))
1162 return -ENOMEM;
1163 return 0;
1164}
1165
1166static void __net_exit ping_v4_proc_exit_net(struct net *net)
1167{
1168 remove_proc_entry("icmp", net->proc_net);
1169}
1170
1171static struct pernet_operations ping_v4_net_ops = {
1172 .init = ping_v4_proc_init_net,
1173 .exit = ping_v4_proc_exit_net,
1174};
1175
1176int __init ping_proc_init(void)
1177{
1178 return register_pernet_subsys(&ping_v4_net_ops);
1179}
1180
1181void ping_proc_exit(void)
1182{
1183 unregister_pernet_subsys(&ping_v4_net_ops);
1184}
1185
1186#endif
1187
1188void __init ping_init(void)
1189{
1190 int i;
1191
1192 for (i = 0; i < PING_HTABLE_SIZE; i++)
1193 INIT_HLIST_HEAD(&ping_table.hash[i]);
1194 spin_lock_init(&ping_table.lock);
1195}
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
50static struct ping_table ping_table;
51
52static u16 ping_port_rover;
53
54static inline int ping_hashfn(struct net *net, unsigned int num, unsigned int mask)
55{
56 int res = (num + net_hash_mix(net)) & mask;
57
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 int 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 write_lock_bh(&ping_table.lock);
141 hlist_nulls_del(&sk->sk_nulls_node);
142 sock_put(sk);
143 isk->inet_num = 0;
144 isk->inet_sport = 0;
145 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
146 write_unlock_bh(&ping_table.lock);
147 }
148}
149
150static struct sock *ping_v4_lookup(struct net *net, __be32 saddr, __be32 daddr,
151 u16 ident, int dif)
152{
153 struct hlist_nulls_head *hslot = ping_hashslot(&ping_table, net, ident);
154 struct sock *sk = NULL;
155 struct inet_sock *isk;
156 struct hlist_nulls_node *hnode;
157
158 pr_debug("try to find: num = %d, daddr = %pI4, dif = %d\n",
159 (int)ident, &daddr, dif);
160 read_lock_bh(&ping_table.lock);
161
162 ping_portaddr_for_each_entry(sk, hnode, hslot) {
163 isk = inet_sk(sk);
164
165 pr_debug("found: %p: num = %d, daddr = %pI4, dif = %d\n", sk,
166 (int)isk->inet_num, &isk->inet_rcv_saddr,
167 sk->sk_bound_dev_if);
168
169 pr_debug("iterate\n");
170 if (isk->inet_num != ident)
171 continue;
172 if (isk->inet_rcv_saddr && isk->inet_rcv_saddr != daddr)
173 continue;
174 if (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif)
175 continue;
176
177 sock_hold(sk);
178 goto exit;
179 }
180
181 sk = NULL;
182exit:
183 read_unlock_bh(&ping_table.lock);
184
185 return sk;
186}
187
188static void inet_get_ping_group_range_net(struct net *net, gid_t *low,
189 gid_t *high)
190{
191 gid_t *data = net->ipv4.sysctl_ping_group_range;
192 unsigned int seq;
193
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 kgid_t low, high;
211
212 inet_get_ping_group_range_net(net, range, range+1);
213 low = make_kgid(&init_user_ns, range[0]);
214 high = make_kgid(&init_user_ns, range[1]);
215 if (!gid_valid(low) || !gid_valid(high) || gid_lt(high, low))
216 return -EACCES;
217
218 if (range[0] <= group && group <= range[1])
219 return 0;
220
221 for (i = 0; i < group_info->nblocks; i++) {
222 int cp_count = min_t(int, NGROUPS_PER_BLOCK, count);
223 for (j = 0; j < cp_count; j++) {
224 kgid_t gid = group_info->blocks[i][j];
225 if (gid_lte(low, gid) && gid_lte(gid, high))
226 return 0;
227 }
228
229 count -= cp_count;
230 }
231
232 return -EACCES;
233}
234
235static void ping_close(struct sock *sk, long timeout)
236{
237 pr_debug("ping_close(sk=%p,sk->num=%u)\n",
238 inet_sk(sk), inet_sk(sk)->inet_num);
239 pr_debug("isk->refcnt = %d\n", sk->sk_refcnt.counter);
240
241 sk_common_release(sk);
242}
243
244/*
245 * We need our own bind because there are no privileged id's == local ports.
246 * Moreover, we don't allow binding to multi- and broadcast addresses.
247 */
248
249static int ping_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len)
250{
251 struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
252 struct inet_sock *isk = inet_sk(sk);
253 unsigned short snum;
254 int chk_addr_ret;
255 int err;
256
257 if (addr_len < sizeof(struct sockaddr_in))
258 return -EINVAL;
259
260 pr_debug("ping_v4_bind(sk=%p,sa_addr=%08x,sa_port=%d)\n",
261 sk, addr->sin_addr.s_addr, ntohs(addr->sin_port));
262
263 chk_addr_ret = inet_addr_type(sock_net(sk), addr->sin_addr.s_addr);
264 if (addr->sin_addr.s_addr == htonl(INADDR_ANY))
265 chk_addr_ret = RTN_LOCAL;
266
267 if ((sysctl_ip_nonlocal_bind == 0 &&
268 isk->freebind == 0 && isk->transparent == 0 &&
269 chk_addr_ret != RTN_LOCAL) ||
270 chk_addr_ret == RTN_MULTICAST ||
271 chk_addr_ret == RTN_BROADCAST)
272 return -EADDRNOTAVAIL;
273
274 lock_sock(sk);
275
276 err = -EINVAL;
277 if (isk->inet_num != 0)
278 goto out;
279
280 err = -EADDRINUSE;
281 isk->inet_rcv_saddr = isk->inet_saddr = addr->sin_addr.s_addr;
282 snum = ntohs(addr->sin_port);
283 if (ping_v4_get_port(sk, snum) != 0) {
284 isk->inet_saddr = isk->inet_rcv_saddr = 0;
285 goto out;
286 }
287
288 pr_debug("after bind(): num = %d, daddr = %pI4, dif = %d\n",
289 (int)isk->inet_num,
290 &isk->inet_rcv_saddr,
291 (int)sk->sk_bound_dev_if);
292
293 err = 0;
294 if (isk->inet_rcv_saddr)
295 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
296 if (snum)
297 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
298 isk->inet_sport = htons(isk->inet_num);
299 isk->inet_daddr = 0;
300 isk->inet_dport = 0;
301 sk_dst_reset(sk);
302out:
303 release_sock(sk);
304 pr_debug("ping_v4_bind -> %d\n", err);
305 return err;
306}
307
308/*
309 * Is this a supported type of ICMP message?
310 */
311
312static inline int ping_supported(int type, int code)
313{
314 if (type == ICMP_ECHO && code == 0)
315 return 1;
316 return 0;
317}
318
319/*
320 * This routine is called by the ICMP module when it gets some
321 * sort of error condition.
322 */
323
324static int ping_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
325
326void ping_err(struct sk_buff *skb, u32 info)
327{
328 struct iphdr *iph = (struct iphdr *)skb->data;
329 struct icmphdr *icmph = (struct icmphdr *)(skb->data+(iph->ihl<<2));
330 struct inet_sock *inet_sock;
331 int type = icmph->type;
332 int code = icmph->code;
333 struct net *net = dev_net(skb->dev);
334 struct sock *sk;
335 int harderr;
336 int err;
337
338 /* We assume the packet has already been checked by icmp_unreach */
339
340 if (!ping_supported(icmph->type, icmph->code))
341 return;
342
343 pr_debug("ping_err(type=%04x,code=%04x,id=%04x,seq=%04x)\n", type,
344 code, ntohs(icmph->un.echo.id), ntohs(icmph->un.echo.sequence));
345
346 sk = ping_v4_lookup(net, iph->daddr, iph->saddr,
347 ntohs(icmph->un.echo.id), skb->dev->ifindex);
348 if (sk == NULL) {
349 pr_debug("no socket, dropping\n");
350 return; /* No socket for error */
351 }
352 pr_debug("err on socket %p\n", sk);
353
354 err = 0;
355 harderr = 0;
356 inet_sock = inet_sk(sk);
357
358 switch (type) {
359 default:
360 case ICMP_TIME_EXCEEDED:
361 err = EHOSTUNREACH;
362 break;
363 case ICMP_SOURCE_QUENCH:
364 /* This is not a real error but ping wants to see it.
365 * Report it with some fake errno. */
366 err = EREMOTEIO;
367 break;
368 case ICMP_PARAMETERPROB:
369 err = EPROTO;
370 harderr = 1;
371 break;
372 case ICMP_DEST_UNREACH:
373 if (code == ICMP_FRAG_NEEDED) { /* Path MTU discovery */
374 if (inet_sock->pmtudisc != IP_PMTUDISC_DONT) {
375 err = EMSGSIZE;
376 harderr = 1;
377 break;
378 }
379 goto out;
380 }
381 err = EHOSTUNREACH;
382 if (code <= NR_ICMP_UNREACH) {
383 harderr = icmp_err_convert[code].fatal;
384 err = icmp_err_convert[code].errno;
385 }
386 break;
387 case ICMP_REDIRECT:
388 /* See ICMP_SOURCE_QUENCH */
389 err = EREMOTEIO;
390 break;
391 }
392
393 /*
394 * RFC1122: OK. Passes ICMP errors back to application, as per
395 * 4.1.3.3.
396 */
397 if (!inet_sock->recverr) {
398 if (!harderr || sk->sk_state != TCP_ESTABLISHED)
399 goto out;
400 } else {
401 ip_icmp_error(sk, skb, err, 0 /* no remote port */,
402 info, (u8 *)icmph);
403 }
404 sk->sk_err = err;
405 sk->sk_error_report(sk);
406out:
407 sock_put(sk);
408}
409
410/*
411 * Copy and checksum an ICMP Echo packet from user space into a buffer.
412 */
413
414struct pingfakehdr {
415 struct icmphdr icmph;
416 struct iovec *iov;
417 __wsum wcheck;
418};
419
420static int ping_getfrag(void *from, char *to,
421 int offset, int fraglen, int odd, struct sk_buff *skb)
422{
423 struct pingfakehdr *pfh = (struct pingfakehdr *)from;
424
425 if (offset == 0) {
426 if (fraglen < sizeof(struct icmphdr))
427 BUG();
428 if (csum_partial_copy_fromiovecend(to + sizeof(struct icmphdr),
429 pfh->iov, 0, fraglen - sizeof(struct icmphdr),
430 &pfh->wcheck))
431 return -EFAULT;
432
433 return 0;
434 }
435 if (offset < sizeof(struct icmphdr))
436 BUG();
437 if (csum_partial_copy_fromiovecend
438 (to, pfh->iov, offset - sizeof(struct icmphdr),
439 fraglen, &pfh->wcheck))
440 return -EFAULT;
441 return 0;
442}
443
444static int ping_push_pending_frames(struct sock *sk, struct pingfakehdr *pfh,
445 struct flowi4 *fl4)
446{
447 struct sk_buff *skb = skb_peek(&sk->sk_write_queue);
448
449 pfh->wcheck = csum_partial((char *)&pfh->icmph,
450 sizeof(struct icmphdr), pfh->wcheck);
451 pfh->icmph.checksum = csum_fold(pfh->wcheck);
452 memcpy(icmp_hdr(skb), &pfh->icmph, sizeof(struct icmphdr));
453 skb->ip_summed = CHECKSUM_NONE;
454 return ip_push_pending_frames(sk, fl4);
455}
456
457static int ping_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
458 size_t len)
459{
460 struct net *net = sock_net(sk);
461 struct flowi4 fl4;
462 struct inet_sock *inet = inet_sk(sk);
463 struct ipcm_cookie ipc;
464 struct icmphdr user_icmph;
465 struct pingfakehdr pfh;
466 struct rtable *rt = NULL;
467 struct ip_options_data opt_copy;
468 int free = 0;
469 __be32 saddr, daddr, faddr;
470 u8 tos;
471 int err;
472
473 pr_debug("ping_sendmsg(sk=%p,sk->num=%u)\n", inet, inet->inet_num);
474
475
476 if (len > 0xFFFF)
477 return -EMSGSIZE;
478
479 /*
480 * Check the flags.
481 */
482
483 /* Mirror BSD error message compatibility */
484 if (msg->msg_flags & MSG_OOB)
485 return -EOPNOTSUPP;
486
487 /*
488 * Fetch the ICMP header provided by the userland.
489 * iovec is modified!
490 */
491
492 if (memcpy_fromiovec((u8 *)&user_icmph, msg->msg_iov,
493 sizeof(struct icmphdr)))
494 return -EFAULT;
495 if (!ping_supported(user_icmph.type, user_icmph.code))
496 return -EINVAL;
497
498 /*
499 * Get and verify the address.
500 */
501
502 if (msg->msg_name) {
503 struct sockaddr_in *usin = (struct sockaddr_in *)msg->msg_name;
504 if (msg->msg_namelen < sizeof(*usin))
505 return -EINVAL;
506 if (usin->sin_family != AF_INET)
507 return -EINVAL;
508 daddr = usin->sin_addr.s_addr;
509 /* no remote port */
510 } else {
511 if (sk->sk_state != TCP_ESTABLISHED)
512 return -EDESTADDRREQ;
513 daddr = inet->inet_daddr;
514 /* no remote port */
515 }
516
517 ipc.addr = inet->inet_saddr;
518 ipc.opt = NULL;
519 ipc.oif = sk->sk_bound_dev_if;
520 ipc.tx_flags = 0;
521 err = sock_tx_timestamp(sk, &ipc.tx_flags);
522 if (err)
523 return err;
524
525 if (msg->msg_controllen) {
526 err = ip_cmsg_send(sock_net(sk), msg, &ipc);
527 if (err)
528 return err;
529 if (ipc.opt)
530 free = 1;
531 }
532 if (!ipc.opt) {
533 struct ip_options_rcu *inet_opt;
534
535 rcu_read_lock();
536 inet_opt = rcu_dereference(inet->inet_opt);
537 if (inet_opt) {
538 memcpy(&opt_copy, inet_opt,
539 sizeof(*inet_opt) + inet_opt->opt.optlen);
540 ipc.opt = &opt_copy.opt;
541 }
542 rcu_read_unlock();
543 }
544
545 saddr = ipc.addr;
546 ipc.addr = faddr = daddr;
547
548 if (ipc.opt && ipc.opt->opt.srr) {
549 if (!daddr)
550 return -EINVAL;
551 faddr = ipc.opt->opt.faddr;
552 }
553 tos = RT_TOS(inet->tos);
554 if (sock_flag(sk, SOCK_LOCALROUTE) ||
555 (msg->msg_flags & MSG_DONTROUTE) ||
556 (ipc.opt && ipc.opt->opt.is_strictroute)) {
557 tos |= RTO_ONLINK;
558 }
559
560 if (ipv4_is_multicast(daddr)) {
561 if (!ipc.oif)
562 ipc.oif = inet->mc_index;
563 if (!saddr)
564 saddr = inet->mc_addr;
565 } else if (!ipc.oif)
566 ipc.oif = inet->uc_index;
567
568 flowi4_init_output(&fl4, ipc.oif, sk->sk_mark, tos,
569 RT_SCOPE_UNIVERSE, sk->sk_protocol,
570 inet_sk_flowi_flags(sk), faddr, saddr, 0, 0);
571
572 security_sk_classify_flow(sk, flowi4_to_flowi(&fl4));
573 rt = ip_route_output_flow(net, &fl4, sk);
574 if (IS_ERR(rt)) {
575 err = PTR_ERR(rt);
576 rt = NULL;
577 if (err == -ENETUNREACH)
578 IP_INC_STATS_BH(net, IPSTATS_MIB_OUTNOROUTES);
579 goto out;
580 }
581
582 err = -EACCES;
583 if ((rt->rt_flags & RTCF_BROADCAST) &&
584 !sock_flag(sk, SOCK_BROADCAST))
585 goto out;
586
587 if (msg->msg_flags & MSG_CONFIRM)
588 goto do_confirm;
589back_from_confirm:
590
591 if (!ipc.addr)
592 ipc.addr = fl4.daddr;
593
594 lock_sock(sk);
595
596 pfh.icmph.type = user_icmph.type; /* already checked */
597 pfh.icmph.code = user_icmph.code; /* ditto */
598 pfh.icmph.checksum = 0;
599 pfh.icmph.un.echo.id = inet->inet_sport;
600 pfh.icmph.un.echo.sequence = user_icmph.un.echo.sequence;
601 pfh.iov = msg->msg_iov;
602 pfh.wcheck = 0;
603
604 err = ip_append_data(sk, &fl4, ping_getfrag, &pfh, len,
605 0, &ipc, &rt, msg->msg_flags);
606 if (err)
607 ip_flush_pending_frames(sk);
608 else
609 err = ping_push_pending_frames(sk, &pfh, &fl4);
610 release_sock(sk);
611
612out:
613 ip_rt_put(rt);
614 if (free)
615 kfree(ipc.opt);
616 if (!err) {
617 icmp_out_count(sock_net(sk), user_icmph.type);
618 return len;
619 }
620 return err;
621
622do_confirm:
623 dst_confirm(&rt->dst);
624 if (!(msg->msg_flags & MSG_PROBE) || len)
625 goto back_from_confirm;
626 err = 0;
627 goto out;
628}
629
630static int ping_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
631 size_t len, int noblock, int flags, int *addr_len)
632{
633 struct inet_sock *isk = inet_sk(sk);
634 struct sockaddr_in *sin = (struct sockaddr_in *)msg->msg_name;
635 struct sk_buff *skb;
636 int copied, err;
637
638 pr_debug("ping_recvmsg(sk=%p,sk->num=%u)\n", isk, isk->inet_num);
639
640 err = -EOPNOTSUPP;
641 if (flags & MSG_OOB)
642 goto out;
643
644 if (addr_len)
645 *addr_len = sizeof(*sin);
646
647 if (flags & MSG_ERRQUEUE)
648 return ip_recv_error(sk, msg, len);
649
650 skb = skb_recv_datagram(sk, flags, noblock, &err);
651 if (!skb)
652 goto out;
653
654 copied = skb->len;
655 if (copied > len) {
656 msg->msg_flags |= MSG_TRUNC;
657 copied = len;
658 }
659
660 /* Don't bother checking the checksum */
661 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
662 if (err)
663 goto done;
664
665 sock_recv_timestamp(msg, sk, skb);
666
667 /* Copy the address. */
668 if (sin) {
669 sin->sin_family = AF_INET;
670 sin->sin_port = 0 /* skb->h.uh->source */;
671 sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
672 memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
673 }
674 if (isk->cmsg_flags)
675 ip_cmsg_recv(msg, skb);
676 err = copied;
677
678done:
679 skb_free_datagram(sk, skb);
680out:
681 pr_debug("ping_recvmsg -> %d\n", err);
682 return err;
683}
684
685static int ping_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
686{
687 pr_debug("ping_queue_rcv_skb(sk=%p,sk->num=%d,skb=%p)\n",
688 inet_sk(sk), inet_sk(sk)->inet_num, skb);
689 if (sock_queue_rcv_skb(sk, skb) < 0) {
690 kfree_skb(skb);
691 pr_debug("ping_queue_rcv_skb -> failed\n");
692 return -1;
693 }
694 return 0;
695}
696
697
698/*
699 * All we need to do is get the socket.
700 */
701
702void ping_rcv(struct sk_buff *skb)
703{
704 struct sock *sk;
705 struct net *net = dev_net(skb->dev);
706 struct iphdr *iph = ip_hdr(skb);
707 struct icmphdr *icmph = icmp_hdr(skb);
708 __be32 saddr = iph->saddr;
709 __be32 daddr = iph->daddr;
710
711 /* We assume the packet has already been checked by icmp_rcv */
712
713 pr_debug("ping_rcv(skb=%p,id=%04x,seq=%04x)\n",
714 skb, ntohs(icmph->un.echo.id), ntohs(icmph->un.echo.sequence));
715
716 /* Push ICMP header back */
717 skb_push(skb, skb->data - (u8 *)icmph);
718
719 sk = ping_v4_lookup(net, saddr, daddr, ntohs(icmph->un.echo.id),
720 skb->dev->ifindex);
721 if (sk != NULL) {
722 pr_debug("rcv on socket %p\n", sk);
723 ping_queue_rcv_skb(sk, skb_get(skb));
724 sock_put(sk);
725 return;
726 }
727 pr_debug("no socket, dropping\n");
728
729 /* We're called from icmp_rcv(). kfree_skb() is done there. */
730}
731
732struct proto ping_prot = {
733 .name = "PING",
734 .owner = THIS_MODULE,
735 .init = ping_init_sock,
736 .close = ping_close,
737 .connect = ip4_datagram_connect,
738 .disconnect = udp_disconnect,
739 .setsockopt = ip_setsockopt,
740 .getsockopt = ip_getsockopt,
741 .sendmsg = ping_sendmsg,
742 .recvmsg = ping_recvmsg,
743 .bind = ping_bind,
744 .backlog_rcv = ping_queue_rcv_skb,
745 .hash = ping_v4_hash,
746 .unhash = ping_v4_unhash,
747 .get_port = ping_v4_get_port,
748 .obj_size = sizeof(struct inet_sock),
749};
750EXPORT_SYMBOL(ping_prot);
751
752#ifdef CONFIG_PROC_FS
753
754static struct sock *ping_get_first(struct seq_file *seq, int start)
755{
756 struct sock *sk;
757 struct ping_iter_state *state = seq->private;
758 struct net *net = seq_file_net(seq);
759
760 for (state->bucket = start; state->bucket < PING_HTABLE_SIZE;
761 ++state->bucket) {
762 struct hlist_nulls_node *node;
763 struct hlist_nulls_head *hslot;
764
765 hslot = &ping_table.hash[state->bucket];
766
767 if (hlist_nulls_empty(hslot))
768 continue;
769
770 sk_nulls_for_each(sk, node, hslot) {
771 if (net_eq(sock_net(sk), net))
772 goto found;
773 }
774 }
775 sk = NULL;
776found:
777 return sk;
778}
779
780static struct sock *ping_get_next(struct seq_file *seq, struct sock *sk)
781{
782 struct ping_iter_state *state = seq->private;
783 struct net *net = seq_file_net(seq);
784
785 do {
786 sk = sk_nulls_next(sk);
787 } while (sk && (!net_eq(sock_net(sk), net)));
788
789 if (!sk)
790 return ping_get_first(seq, state->bucket + 1);
791 return sk;
792}
793
794static struct sock *ping_get_idx(struct seq_file *seq, loff_t pos)
795{
796 struct sock *sk = ping_get_first(seq, 0);
797
798 if (sk)
799 while (pos && (sk = ping_get_next(seq, sk)) != NULL)
800 --pos;
801 return pos ? NULL : sk;
802}
803
804static void *ping_seq_start(struct seq_file *seq, loff_t *pos)
805{
806 struct ping_iter_state *state = seq->private;
807 state->bucket = 0;
808
809 read_lock_bh(&ping_table.lock);
810
811 return *pos ? ping_get_idx(seq, *pos-1) : SEQ_START_TOKEN;
812}
813
814static void *ping_seq_next(struct seq_file *seq, void *v, loff_t *pos)
815{
816 struct sock *sk;
817
818 if (v == SEQ_START_TOKEN)
819 sk = ping_get_idx(seq, 0);
820 else
821 sk = ping_get_next(seq, v);
822
823 ++*pos;
824 return sk;
825}
826
827static void ping_seq_stop(struct seq_file *seq, void *v)
828{
829 read_unlock_bh(&ping_table.lock);
830}
831
832static void ping_format_sock(struct sock *sp, struct seq_file *f,
833 int bucket, int *len)
834{
835 struct inet_sock *inet = inet_sk(sp);
836 __be32 dest = inet->inet_daddr;
837 __be32 src = inet->inet_rcv_saddr;
838 __u16 destp = ntohs(inet->inet_dport);
839 __u16 srcp = ntohs(inet->inet_sport);
840
841 seq_printf(f, "%5d: %08X:%04X %08X:%04X"
842 " %02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %pK %d%n",
843 bucket, src, srcp, dest, destp, sp->sk_state,
844 sk_wmem_alloc_get(sp),
845 sk_rmem_alloc_get(sp),
846 0, 0L, 0, sock_i_uid(sp), 0, sock_i_ino(sp),
847 atomic_read(&sp->sk_refcnt), sp,
848 atomic_read(&sp->sk_drops), len);
849}
850
851static int ping_seq_show(struct seq_file *seq, void *v)
852{
853 if (v == SEQ_START_TOKEN)
854 seq_printf(seq, "%-127s\n",
855 " sl local_address rem_address st tx_queue "
856 "rx_queue tr tm->when retrnsmt uid timeout "
857 "inode ref pointer drops");
858 else {
859 struct ping_iter_state *state = seq->private;
860 int len;
861
862 ping_format_sock(v, seq, state->bucket, &len);
863 seq_printf(seq, "%*s\n", 127 - len, "");
864 }
865 return 0;
866}
867
868static const struct seq_operations ping_seq_ops = {
869 .show = ping_seq_show,
870 .start = ping_seq_start,
871 .next = ping_seq_next,
872 .stop = ping_seq_stop,
873};
874
875static int ping_seq_open(struct inode *inode, struct file *file)
876{
877 return seq_open_net(inode, file, &ping_seq_ops,
878 sizeof(struct ping_iter_state));
879}
880
881static const struct file_operations ping_seq_fops = {
882 .open = ping_seq_open,
883 .read = seq_read,
884 .llseek = seq_lseek,
885 .release = seq_release_net,
886};
887
888static int ping_proc_register(struct net *net)
889{
890 struct proc_dir_entry *p;
891 int rc = 0;
892
893 p = proc_net_fops_create(net, "icmp", S_IRUGO, &ping_seq_fops);
894 if (!p)
895 rc = -ENOMEM;
896 return rc;
897}
898
899static void ping_proc_unregister(struct net *net)
900{
901 proc_net_remove(net, "icmp");
902}
903
904
905static int __net_init ping_proc_init_net(struct net *net)
906{
907 return ping_proc_register(net);
908}
909
910static void __net_exit ping_proc_exit_net(struct net *net)
911{
912 ping_proc_unregister(net);
913}
914
915static struct pernet_operations ping_net_ops = {
916 .init = ping_proc_init_net,
917 .exit = ping_proc_exit_net,
918};
919
920int __init ping_proc_init(void)
921{
922 return register_pernet_subsys(&ping_net_ops);
923}
924
925void ping_proc_exit(void)
926{
927 unregister_pernet_subsys(&ping_net_ops);
928}
929
930#endif
931
932void __init ping_init(void)
933{
934 int i;
935
936 for (i = 0; i < PING_HTABLE_SIZE; i++)
937 INIT_HLIST_NULLS_HEAD(&ping_table.hash[i], i);
938 rwlock_init(&ping_table.lock);
939}