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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// 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 <net/sock.h>
37#include <net/ping.h>
38#include <net/udp.h>
39#include <net/route.h>
40#include <net/inet_common.h>
41#include <net/checksum.h>
42
43#if IS_ENABLED(CONFIG_IPV6)
44#include <linux/in6.h>
45#include <linux/icmpv6.h>
46#include <net/addrconf.h>
47#include <net/ipv6.h>
48#include <net/transp_v6.h>
49#endif
50
51struct ping_table {
52 struct hlist_nulls_head hash[PING_HTABLE_SIZE];
53 rwlock_t lock;
54};
55
56static struct ping_table ping_table;
57struct pingv6_ops pingv6_ops;
58EXPORT_SYMBOL_GPL(pingv6_ops);
59
60static u16 ping_port_rover;
61
62static inline u32 ping_hashfn(const struct net *net, u32 num, u32 mask)
63{
64 u32 res = (num + net_hash_mix(net)) & mask;
65
66 pr_debug("hash(%u) = %u\n", num, res);
67 return res;
68}
69EXPORT_SYMBOL_GPL(ping_hash);
70
71static inline struct hlist_nulls_head *ping_hashslot(struct ping_table *table,
72 struct net *net, unsigned int num)
73{
74 return &table->hash[ping_hashfn(net, num, PING_HTABLE_MASK)];
75}
76
77int ping_get_port(struct sock *sk, unsigned short ident)
78{
79 struct hlist_nulls_node *node;
80 struct hlist_nulls_head *hlist;
81 struct inet_sock *isk, *isk2;
82 struct sock *sk2 = NULL;
83
84 isk = inet_sk(sk);
85 write_lock_bh(&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 ping_portaddr_for_each_entry(sk2, node, 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 ping_portaddr_for_each_entry(sk2, node, 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 sock_hold(sk);
131 hlist_nulls_add_head(&sk->sk_nulls_node, hlist);
132 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
133 }
134 write_unlock_bh(&ping_table.lock);
135 return 0;
136
137fail:
138 write_unlock_bh(&ping_table.lock);
139 return 1;
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 write_lock_bh(&ping_table.lock);
157 if (sk_hashed(sk)) {
158 hlist_nulls_del(&sk->sk_nulls_node);
159 sk_nulls_node_init(&sk->sk_nulls_node);
160 sock_put(sk);
161 isk->inet_num = 0;
162 isk->inet_sport = 0;
163 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
164 }
165 write_unlock_bh(&ping_table.lock);
166}
167EXPORT_SYMBOL_GPL(ping_unhash);
168
169static struct sock *ping_lookup(struct net *net, struct sk_buff *skb, u16 ident)
170{
171 struct hlist_nulls_head *hslot = ping_hashslot(&ping_table, net, ident);
172 struct sock *sk = NULL;
173 struct inet_sock *isk;
174 struct hlist_nulls_node *hnode;
175 int dif = skb->dev->ifindex;
176
177 if (skb->protocol == htons(ETH_P_IP)) {
178 pr_debug("try to find: num = %d, daddr = %pI4, dif = %d\n",
179 (int)ident, &ip_hdr(skb)->daddr, dif);
180#if IS_ENABLED(CONFIG_IPV6)
181 } else if (skb->protocol == htons(ETH_P_IPV6)) {
182 pr_debug("try to find: num = %d, daddr = %pI6c, dif = %d\n",
183 (int)ident, &ipv6_hdr(skb)->daddr, dif);
184#endif
185 }
186
187 read_lock_bh(&ping_table.lock);
188
189 ping_portaddr_for_each_entry(sk, hnode, hslot) {
190 isk = inet_sk(sk);
191
192 pr_debug("iterate\n");
193 if (isk->inet_num != ident)
194 continue;
195
196 if (skb->protocol == htons(ETH_P_IP) &&
197 sk->sk_family == AF_INET) {
198 pr_debug("found: %p: num=%d, daddr=%pI4, dif=%d\n", sk,
199 (int) isk->inet_num, &isk->inet_rcv_saddr,
200 sk->sk_bound_dev_if);
201
202 if (isk->inet_rcv_saddr &&
203 isk->inet_rcv_saddr != ip_hdr(skb)->daddr)
204 continue;
205#if IS_ENABLED(CONFIG_IPV6)
206 } else if (skb->protocol == htons(ETH_P_IPV6) &&
207 sk->sk_family == AF_INET6) {
208
209 pr_debug("found: %p: num=%d, daddr=%pI6c, dif=%d\n", sk,
210 (int) isk->inet_num,
211 &sk->sk_v6_rcv_saddr,
212 sk->sk_bound_dev_if);
213
214 if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr) &&
215 !ipv6_addr_equal(&sk->sk_v6_rcv_saddr,
216 &ipv6_hdr(skb)->daddr))
217 continue;
218#endif
219 } else {
220 continue;
221 }
222
223 if (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif)
224 continue;
225
226 sock_hold(sk);
227 goto exit;
228 }
229
230 sk = NULL;
231exit:
232 read_unlock_bh(&ping_table.lock);
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
294/* Checks the bind address and possibly modifies sk->sk_bound_dev_if. */
295static int ping_check_bind_addr(struct sock *sk, struct inet_sock *isk,
296 struct sockaddr *uaddr, int addr_len) {
297 struct net *net = sock_net(sk);
298 if (sk->sk_family == AF_INET) {
299 struct sockaddr_in *addr = (struct sockaddr_in *) uaddr;
300 int chk_addr_ret;
301
302 if (addr_len < sizeof(*addr))
303 return -EINVAL;
304
305 if (addr->sin_family != AF_INET &&
306 !(addr->sin_family == AF_UNSPEC &&
307 addr->sin_addr.s_addr == htonl(INADDR_ANY)))
308 return -EAFNOSUPPORT;
309
310 pr_debug("ping_check_bind_addr(sk=%p,addr=%pI4,port=%d)\n",
311 sk, &addr->sin_addr.s_addr, ntohs(addr->sin_port));
312
313 chk_addr_ret = inet_addr_type(net, addr->sin_addr.s_addr);
314
315 if (addr->sin_addr.s_addr == htonl(INADDR_ANY))
316 chk_addr_ret = RTN_LOCAL;
317
318 if ((!inet_can_nonlocal_bind(net, isk) &&
319 chk_addr_ret != RTN_LOCAL) ||
320 chk_addr_ret == RTN_MULTICAST ||
321 chk_addr_ret == RTN_BROADCAST)
322 return -EADDRNOTAVAIL;
323
324#if IS_ENABLED(CONFIG_IPV6)
325 } else if (sk->sk_family == AF_INET6) {
326 struct sockaddr_in6 *addr = (struct sockaddr_in6 *) uaddr;
327 int addr_type, scoped, has_addr;
328 struct net_device *dev = NULL;
329
330 if (addr_len < sizeof(*addr))
331 return -EINVAL;
332
333 if (addr->sin6_family != AF_INET6)
334 return -EAFNOSUPPORT;
335
336 pr_debug("ping_check_bind_addr(sk=%p,addr=%pI6c,port=%d)\n",
337 sk, addr->sin6_addr.s6_addr, ntohs(addr->sin6_port));
338
339 addr_type = ipv6_addr_type(&addr->sin6_addr);
340 scoped = __ipv6_addr_needs_scope_id(addr_type);
341 if ((addr_type != IPV6_ADDR_ANY &&
342 !(addr_type & IPV6_ADDR_UNICAST)) ||
343 (scoped && !addr->sin6_scope_id))
344 return -EINVAL;
345
346 rcu_read_lock();
347 if (addr->sin6_scope_id) {
348 dev = dev_get_by_index_rcu(net, addr->sin6_scope_id);
349 if (!dev) {
350 rcu_read_unlock();
351 return -ENODEV;
352 }
353 }
354 has_addr = pingv6_ops.ipv6_chk_addr(net, &addr->sin6_addr, dev,
355 scoped);
356 rcu_read_unlock();
357
358 if (!(ipv6_can_nonlocal_bind(net, isk) || has_addr ||
359 addr_type == IPV6_ADDR_ANY))
360 return -EADDRNOTAVAIL;
361
362 if (scoped)
363 sk->sk_bound_dev_if = addr->sin6_scope_id;
364#endif
365 } else {
366 return -EAFNOSUPPORT;
367 }
368 return 0;
369}
370
371static void ping_set_saddr(struct sock *sk, struct sockaddr *saddr)
372{
373 if (saddr->sa_family == AF_INET) {
374 struct inet_sock *isk = inet_sk(sk);
375 struct sockaddr_in *addr = (struct sockaddr_in *) saddr;
376 isk->inet_rcv_saddr = isk->inet_saddr = addr->sin_addr.s_addr;
377#if IS_ENABLED(CONFIG_IPV6)
378 } else if (saddr->sa_family == AF_INET6) {
379 struct sockaddr_in6 *addr = (struct sockaddr_in6 *) saddr;
380 struct ipv6_pinfo *np = inet6_sk(sk);
381 sk->sk_v6_rcv_saddr = np->saddr = addr->sin6_addr;
382#endif
383 }
384}
385
386static void ping_clear_saddr(struct sock *sk, int dif)
387{
388 sk->sk_bound_dev_if = dif;
389 if (sk->sk_family == AF_INET) {
390 struct inet_sock *isk = inet_sk(sk);
391 isk->inet_rcv_saddr = isk->inet_saddr = 0;
392#if IS_ENABLED(CONFIG_IPV6)
393 } else if (sk->sk_family == AF_INET6) {
394 struct ipv6_pinfo *np = inet6_sk(sk);
395 memset(&sk->sk_v6_rcv_saddr, 0, sizeof(sk->sk_v6_rcv_saddr));
396 memset(&np->saddr, 0, sizeof(np->saddr));
397#endif
398 }
399}
400/*
401 * We need our own bind because there are no privileged id's == local ports.
402 * Moreover, we don't allow binding to multi- and broadcast addresses.
403 */
404
405int ping_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len)
406{
407 struct inet_sock *isk = inet_sk(sk);
408 unsigned short snum;
409 int err;
410 int dif = sk->sk_bound_dev_if;
411
412 err = ping_check_bind_addr(sk, isk, uaddr, addr_len);
413 if (err)
414 return err;
415
416 lock_sock(sk);
417
418 err = -EINVAL;
419 if (isk->inet_num != 0)
420 goto out;
421
422 err = -EADDRINUSE;
423 ping_set_saddr(sk, uaddr);
424 snum = ntohs(((struct sockaddr_in *)uaddr)->sin_port);
425 if (ping_get_port(sk, snum) != 0) {
426 ping_clear_saddr(sk, dif);
427 goto out;
428 }
429
430 pr_debug("after bind(): num = %hu, dif = %d\n",
431 isk->inet_num,
432 sk->sk_bound_dev_if);
433
434 err = 0;
435 if (sk->sk_family == AF_INET && isk->inet_rcv_saddr)
436 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
437#if IS_ENABLED(CONFIG_IPV6)
438 if (sk->sk_family == AF_INET6 && !ipv6_addr_any(&sk->sk_v6_rcv_saddr))
439 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
440#endif
441
442 if (snum)
443 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
444 isk->inet_sport = htons(isk->inet_num);
445 isk->inet_daddr = 0;
446 isk->inet_dport = 0;
447
448#if IS_ENABLED(CONFIG_IPV6)
449 if (sk->sk_family == AF_INET6)
450 memset(&sk->sk_v6_daddr, 0, sizeof(sk->sk_v6_daddr));
451#endif
452
453 sk_dst_reset(sk);
454out:
455 release_sock(sk);
456 pr_debug("ping_v4_bind -> %d\n", err);
457 return err;
458}
459EXPORT_SYMBOL_GPL(ping_bind);
460
461/*
462 * Is this a supported type of ICMP message?
463 */
464
465static inline int ping_supported(int family, int type, int code)
466{
467 return (family == AF_INET && type == ICMP_ECHO && code == 0) ||
468 (family == AF_INET6 && type == ICMPV6_ECHO_REQUEST && code == 0);
469}
470
471/*
472 * This routine is called by the ICMP module when it gets some
473 * sort of error condition.
474 */
475
476void ping_err(struct sk_buff *skb, int offset, u32 info)
477{
478 int family;
479 struct icmphdr *icmph;
480 struct inet_sock *inet_sock;
481 int type;
482 int code;
483 struct net *net = dev_net(skb->dev);
484 struct sock *sk;
485 int harderr;
486 int err;
487
488 if (skb->protocol == htons(ETH_P_IP)) {
489 family = AF_INET;
490 type = icmp_hdr(skb)->type;
491 code = icmp_hdr(skb)->code;
492 icmph = (struct icmphdr *)(skb->data + offset);
493 } else if (skb->protocol == htons(ETH_P_IPV6)) {
494 family = AF_INET6;
495 type = icmp6_hdr(skb)->icmp6_type;
496 code = icmp6_hdr(skb)->icmp6_code;
497 icmph = (struct icmphdr *) (skb->data + offset);
498 } else {
499 BUG();
500 }
501
502 /* We assume the packet has already been checked by icmp_unreach */
503
504 if (!ping_supported(family, icmph->type, icmph->code))
505 return;
506
507 pr_debug("ping_err(proto=0x%x,type=%d,code=%d,id=%04x,seq=%04x)\n",
508 skb->protocol, type, code, ntohs(icmph->un.echo.id),
509 ntohs(icmph->un.echo.sequence));
510
511 sk = ping_lookup(net, skb, ntohs(icmph->un.echo.id));
512 if (!sk) {
513 pr_debug("no socket, dropping\n");
514 return; /* No socket for error */
515 }
516 pr_debug("err on socket %p\n", sk);
517
518 err = 0;
519 harderr = 0;
520 inet_sock = inet_sk(sk);
521
522 if (skb->protocol == htons(ETH_P_IP)) {
523 switch (type) {
524 default:
525 case ICMP_TIME_EXCEEDED:
526 err = EHOSTUNREACH;
527 break;
528 case ICMP_SOURCE_QUENCH:
529 /* This is not a real error but ping wants to see it.
530 * Report it with some fake errno.
531 */
532 err = EREMOTEIO;
533 break;
534 case ICMP_PARAMETERPROB:
535 err = EPROTO;
536 harderr = 1;
537 break;
538 case ICMP_DEST_UNREACH:
539 if (code == ICMP_FRAG_NEEDED) { /* Path MTU discovery */
540 ipv4_sk_update_pmtu(skb, sk, info);
541 if (inet_sock->pmtudisc != IP_PMTUDISC_DONT) {
542 err = EMSGSIZE;
543 harderr = 1;
544 break;
545 }
546 goto out;
547 }
548 err = EHOSTUNREACH;
549 if (code <= NR_ICMP_UNREACH) {
550 harderr = icmp_err_convert[code].fatal;
551 err = icmp_err_convert[code].errno;
552 }
553 break;
554 case ICMP_REDIRECT:
555 /* See ICMP_SOURCE_QUENCH */
556 ipv4_sk_redirect(skb, sk);
557 err = EREMOTEIO;
558 break;
559 }
560#if IS_ENABLED(CONFIG_IPV6)
561 } else if (skb->protocol == htons(ETH_P_IPV6)) {
562 harderr = pingv6_ops.icmpv6_err_convert(type, code, &err);
563#endif
564 }
565
566 /*
567 * RFC1122: OK. Passes ICMP errors back to application, as per
568 * 4.1.3.3.
569 */
570 if ((family == AF_INET && !inet_sock->recverr) ||
571 (family == AF_INET6 && !inet6_sk(sk)->recverr)) {
572 if (!harderr || sk->sk_state != TCP_ESTABLISHED)
573 goto out;
574 } else {
575 if (family == AF_INET) {
576 ip_icmp_error(sk, skb, err, 0 /* no remote port */,
577 info, (u8 *)icmph);
578#if IS_ENABLED(CONFIG_IPV6)
579 } else if (family == AF_INET6) {
580 pingv6_ops.ipv6_icmp_error(sk, skb, err, 0,
581 info, (u8 *)icmph);
582#endif
583 }
584 }
585 sk->sk_err = err;
586 sk->sk_error_report(sk);
587out:
588 sock_put(sk);
589}
590EXPORT_SYMBOL_GPL(ping_err);
591
592/*
593 * Copy and checksum an ICMP Echo packet from user space into a buffer
594 * starting from the payload.
595 */
596
597int ping_getfrag(void *from, char *to,
598 int offset, int fraglen, int odd, struct sk_buff *skb)
599{
600 struct pingfakehdr *pfh = (struct pingfakehdr *)from;
601
602 if (offset == 0) {
603 fraglen -= sizeof(struct icmphdr);
604 if (fraglen < 0)
605 BUG();
606 if (!csum_and_copy_from_iter_full(to + sizeof(struct icmphdr),
607 fraglen, &pfh->wcheck,
608 &pfh->msg->msg_iter))
609 return -EFAULT;
610 } else if (offset < sizeof(struct icmphdr)) {
611 BUG();
612 } else {
613 if (!csum_and_copy_from_iter_full(to, fraglen, &pfh->wcheck,
614 &pfh->msg->msg_iter))
615 return -EFAULT;
616 }
617
618#if IS_ENABLED(CONFIG_IPV6)
619 /* For IPv6, checksum each skb as we go along, as expected by
620 * icmpv6_push_pending_frames. For IPv4, accumulate the checksum in
621 * wcheck, it will be finalized in ping_v4_push_pending_frames.
622 */
623 if (pfh->family == AF_INET6) {
624 skb->csum = pfh->wcheck;
625 skb->ip_summed = CHECKSUM_NONE;
626 pfh->wcheck = 0;
627 }
628#endif
629
630 return 0;
631}
632EXPORT_SYMBOL_GPL(ping_getfrag);
633
634static int ping_v4_push_pending_frames(struct sock *sk, struct pingfakehdr *pfh,
635 struct flowi4 *fl4)
636{
637 struct sk_buff *skb = skb_peek(&sk->sk_write_queue);
638
639 if (!skb)
640 return 0;
641 pfh->wcheck = csum_partial((char *)&pfh->icmph,
642 sizeof(struct icmphdr), pfh->wcheck);
643 pfh->icmph.checksum = csum_fold(pfh->wcheck);
644 memcpy(icmp_hdr(skb), &pfh->icmph, sizeof(struct icmphdr));
645 skb->ip_summed = CHECKSUM_NONE;
646 return ip_push_pending_frames(sk, fl4);
647}
648
649int ping_common_sendmsg(int family, struct msghdr *msg, size_t len,
650 void *user_icmph, size_t icmph_len) {
651 u8 type, code;
652
653 if (len > 0xFFFF)
654 return -EMSGSIZE;
655
656 /* Must have at least a full ICMP header. */
657 if (len < icmph_len)
658 return -EINVAL;
659
660 /*
661 * Check the flags.
662 */
663
664 /* Mirror BSD error message compatibility */
665 if (msg->msg_flags & MSG_OOB)
666 return -EOPNOTSUPP;
667
668 /*
669 * Fetch the ICMP header provided by the userland.
670 * iovec is modified! The ICMP header is consumed.
671 */
672 if (memcpy_from_msg(user_icmph, msg, icmph_len))
673 return -EFAULT;
674
675 if (family == AF_INET) {
676 type = ((struct icmphdr *) user_icmph)->type;
677 code = ((struct icmphdr *) user_icmph)->code;
678#if IS_ENABLED(CONFIG_IPV6)
679 } else if (family == AF_INET6) {
680 type = ((struct icmp6hdr *) user_icmph)->icmp6_type;
681 code = ((struct icmp6hdr *) user_icmph)->icmp6_code;
682#endif
683 } else {
684 BUG();
685 }
686
687 if (!ping_supported(family, type, code))
688 return -EINVAL;
689
690 return 0;
691}
692EXPORT_SYMBOL_GPL(ping_common_sendmsg);
693
694static int ping_v4_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
695{
696 struct net *net = sock_net(sk);
697 struct flowi4 fl4;
698 struct inet_sock *inet = inet_sk(sk);
699 struct ipcm_cookie ipc;
700 struct icmphdr user_icmph;
701 struct pingfakehdr pfh;
702 struct rtable *rt = NULL;
703 struct ip_options_data opt_copy;
704 int free = 0;
705 __be32 saddr, daddr, faddr;
706 u8 tos;
707 int err;
708
709 pr_debug("ping_v4_sendmsg(sk=%p,sk->num=%u)\n", inet, inet->inet_num);
710
711 err = ping_common_sendmsg(AF_INET, msg, len, &user_icmph,
712 sizeof(user_icmph));
713 if (err)
714 return err;
715
716 /*
717 * Get and verify the address.
718 */
719
720 if (msg->msg_name) {
721 DECLARE_SOCKADDR(struct sockaddr_in *, usin, msg->msg_name);
722 if (msg->msg_namelen < sizeof(*usin))
723 return -EINVAL;
724 if (usin->sin_family != AF_INET)
725 return -EAFNOSUPPORT;
726 daddr = usin->sin_addr.s_addr;
727 /* no remote port */
728 } else {
729 if (sk->sk_state != TCP_ESTABLISHED)
730 return -EDESTADDRREQ;
731 daddr = inet->inet_daddr;
732 /* no remote port */
733 }
734
735 ipcm_init_sk(&ipc, inet);
736
737 if (msg->msg_controllen) {
738 err = ip_cmsg_send(sk, msg, &ipc, false);
739 if (unlikely(err)) {
740 kfree(ipc.opt);
741 return err;
742 }
743 if (ipc.opt)
744 free = 1;
745 }
746 if (!ipc.opt) {
747 struct ip_options_rcu *inet_opt;
748
749 rcu_read_lock();
750 inet_opt = rcu_dereference(inet->inet_opt);
751 if (inet_opt) {
752 memcpy(&opt_copy, inet_opt,
753 sizeof(*inet_opt) + inet_opt->opt.optlen);
754 ipc.opt = &opt_copy.opt;
755 }
756 rcu_read_unlock();
757 }
758
759 saddr = ipc.addr;
760 ipc.addr = faddr = daddr;
761
762 if (ipc.opt && ipc.opt->opt.srr) {
763 if (!daddr) {
764 err = -EINVAL;
765 goto out_free;
766 }
767 faddr = ipc.opt->opt.faddr;
768 }
769 tos = get_rttos(&ipc, inet);
770 if (sock_flag(sk, SOCK_LOCALROUTE) ||
771 (msg->msg_flags & MSG_DONTROUTE) ||
772 (ipc.opt && ipc.opt->opt.is_strictroute)) {
773 tos |= RTO_ONLINK;
774 }
775
776 if (ipv4_is_multicast(daddr)) {
777 if (!ipc.oif || netif_index_is_l3_master(sock_net(sk), ipc.oif))
778 ipc.oif = inet->mc_index;
779 if (!saddr)
780 saddr = inet->mc_addr;
781 } else if (!ipc.oif)
782 ipc.oif = inet->uc_index;
783
784 flowi4_init_output(&fl4, ipc.oif, ipc.sockc.mark, tos,
785 RT_SCOPE_UNIVERSE, sk->sk_protocol,
786 inet_sk_flowi_flags(sk), faddr, saddr, 0, 0,
787 sk->sk_uid);
788
789 fl4.fl4_icmp_type = user_icmph.type;
790 fl4.fl4_icmp_code = user_icmph.code;
791
792 security_sk_classify_flow(sk, flowi4_to_flowi(&fl4));
793 rt = ip_route_output_flow(net, &fl4, sk);
794 if (IS_ERR(rt)) {
795 err = PTR_ERR(rt);
796 rt = NULL;
797 if (err == -ENETUNREACH)
798 IP_INC_STATS(net, IPSTATS_MIB_OUTNOROUTES);
799 goto out;
800 }
801
802 err = -EACCES;
803 if ((rt->rt_flags & RTCF_BROADCAST) &&
804 !sock_flag(sk, SOCK_BROADCAST))
805 goto out;
806
807 if (msg->msg_flags & MSG_CONFIRM)
808 goto do_confirm;
809back_from_confirm:
810
811 if (!ipc.addr)
812 ipc.addr = fl4.daddr;
813
814 lock_sock(sk);
815
816 pfh.icmph.type = user_icmph.type; /* already checked */
817 pfh.icmph.code = user_icmph.code; /* ditto */
818 pfh.icmph.checksum = 0;
819 pfh.icmph.un.echo.id = inet->inet_sport;
820 pfh.icmph.un.echo.sequence = user_icmph.un.echo.sequence;
821 pfh.msg = msg;
822 pfh.wcheck = 0;
823 pfh.family = AF_INET;
824
825 err = ip_append_data(sk, &fl4, ping_getfrag, &pfh, len,
826 0, &ipc, &rt, msg->msg_flags);
827 if (err)
828 ip_flush_pending_frames(sk);
829 else
830 err = ping_v4_push_pending_frames(sk, &pfh, &fl4);
831 release_sock(sk);
832
833out:
834 ip_rt_put(rt);
835out_free:
836 if (free)
837 kfree(ipc.opt);
838 if (!err) {
839 icmp_out_count(sock_net(sk), user_icmph.type);
840 return len;
841 }
842 return err;
843
844do_confirm:
845 if (msg->msg_flags & MSG_PROBE)
846 dst_confirm_neigh(&rt->dst, &fl4.daddr);
847 if (!(msg->msg_flags & MSG_PROBE) || len)
848 goto back_from_confirm;
849 err = 0;
850 goto out;
851}
852
853int ping_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int noblock,
854 int flags, int *addr_len)
855{
856 struct inet_sock *isk = inet_sk(sk);
857 int family = sk->sk_family;
858 struct sk_buff *skb;
859 int copied, err;
860
861 pr_debug("ping_recvmsg(sk=%p,sk->num=%u)\n", isk, isk->inet_num);
862
863 err = -EOPNOTSUPP;
864 if (flags & MSG_OOB)
865 goto out;
866
867 if (flags & MSG_ERRQUEUE)
868 return inet_recv_error(sk, msg, len, addr_len);
869
870 skb = skb_recv_datagram(sk, flags, noblock, &err);
871 if (!skb)
872 goto out;
873
874 copied = skb->len;
875 if (copied > len) {
876 msg->msg_flags |= MSG_TRUNC;
877 copied = len;
878 }
879
880 /* Don't bother checking the checksum */
881 err = skb_copy_datagram_msg(skb, 0, msg, copied);
882 if (err)
883 goto done;
884
885 sock_recv_timestamp(msg, sk, skb);
886
887 /* Copy the address and add cmsg data. */
888 if (family == AF_INET) {
889 DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name);
890
891 if (sin) {
892 sin->sin_family = AF_INET;
893 sin->sin_port = 0 /* skb->h.uh->source */;
894 sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
895 memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
896 *addr_len = sizeof(*sin);
897 }
898
899 if (isk->cmsg_flags)
900 ip_cmsg_recv(msg, skb);
901
902#if IS_ENABLED(CONFIG_IPV6)
903 } else if (family == AF_INET6) {
904 struct ipv6_pinfo *np = inet6_sk(sk);
905 struct ipv6hdr *ip6 = ipv6_hdr(skb);
906 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
907
908 if (sin6) {
909 sin6->sin6_family = AF_INET6;
910 sin6->sin6_port = 0;
911 sin6->sin6_addr = ip6->saddr;
912 sin6->sin6_flowinfo = 0;
913 if (np->sndflow)
914 sin6->sin6_flowinfo = ip6_flowinfo(ip6);
915 sin6->sin6_scope_id =
916 ipv6_iface_scope_id(&sin6->sin6_addr,
917 inet6_iif(skb));
918 *addr_len = sizeof(*sin6);
919 }
920
921 if (inet6_sk(sk)->rxopt.all)
922 pingv6_ops.ip6_datagram_recv_common_ctl(sk, msg, skb);
923 if (skb->protocol == htons(ETH_P_IPV6) &&
924 inet6_sk(sk)->rxopt.all)
925 pingv6_ops.ip6_datagram_recv_specific_ctl(sk, msg, skb);
926 else if (skb->protocol == htons(ETH_P_IP) && isk->cmsg_flags)
927 ip_cmsg_recv(msg, skb);
928#endif
929 } else {
930 BUG();
931 }
932
933 err = copied;
934
935done:
936 skb_free_datagram(sk, skb);
937out:
938 pr_debug("ping_recvmsg -> %d\n", err);
939 return err;
940}
941EXPORT_SYMBOL_GPL(ping_recvmsg);
942
943int ping_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
944{
945 pr_debug("ping_queue_rcv_skb(sk=%p,sk->num=%d,skb=%p)\n",
946 inet_sk(sk), inet_sk(sk)->inet_num, skb);
947 if (sock_queue_rcv_skb(sk, skb) < 0) {
948 kfree_skb(skb);
949 pr_debug("ping_queue_rcv_skb -> failed\n");
950 return -1;
951 }
952 return 0;
953}
954EXPORT_SYMBOL_GPL(ping_queue_rcv_skb);
955
956
957/*
958 * All we need to do is get the socket.
959 */
960
961bool ping_rcv(struct sk_buff *skb)
962{
963 struct sock *sk;
964 struct net *net = dev_net(skb->dev);
965 struct icmphdr *icmph = icmp_hdr(skb);
966
967 /* We assume the packet has already been checked by icmp_rcv */
968
969 pr_debug("ping_rcv(skb=%p,id=%04x,seq=%04x)\n",
970 skb, ntohs(icmph->un.echo.id), ntohs(icmph->un.echo.sequence));
971
972 /* Push ICMP header back */
973 skb_push(skb, skb->data - (u8 *)icmph);
974
975 sk = ping_lookup(net, skb, ntohs(icmph->un.echo.id));
976 if (sk) {
977 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
978
979 pr_debug("rcv on socket %p\n", sk);
980 if (skb2)
981 ping_queue_rcv_skb(sk, skb2);
982 sock_put(sk);
983 return true;
984 }
985 pr_debug("no socket, dropping\n");
986
987 return false;
988}
989EXPORT_SYMBOL_GPL(ping_rcv);
990
991struct proto ping_prot = {
992 .name = "PING",
993 .owner = THIS_MODULE,
994 .init = ping_init_sock,
995 .close = ping_close,
996 .connect = ip4_datagram_connect,
997 .disconnect = __udp_disconnect,
998 .setsockopt = ip_setsockopt,
999 .getsockopt = ip_getsockopt,
1000 .sendmsg = ping_v4_sendmsg,
1001 .recvmsg = ping_recvmsg,
1002 .bind = ping_bind,
1003 .backlog_rcv = ping_queue_rcv_skb,
1004 .release_cb = ip4_datagram_release_cb,
1005 .hash = ping_hash,
1006 .unhash = ping_unhash,
1007 .get_port = ping_get_port,
1008 .obj_size = sizeof(struct inet_sock),
1009};
1010EXPORT_SYMBOL(ping_prot);
1011
1012#ifdef CONFIG_PROC_FS
1013
1014static struct sock *ping_get_first(struct seq_file *seq, int start)
1015{
1016 struct sock *sk;
1017 struct ping_iter_state *state = seq->private;
1018 struct net *net = seq_file_net(seq);
1019
1020 for (state->bucket = start; state->bucket < PING_HTABLE_SIZE;
1021 ++state->bucket) {
1022 struct hlist_nulls_node *node;
1023 struct hlist_nulls_head *hslot;
1024
1025 hslot = &ping_table.hash[state->bucket];
1026
1027 if (hlist_nulls_empty(hslot))
1028 continue;
1029
1030 sk_nulls_for_each(sk, node, hslot) {
1031 if (net_eq(sock_net(sk), net) &&
1032 sk->sk_family == state->family)
1033 goto found;
1034 }
1035 }
1036 sk = NULL;
1037found:
1038 return sk;
1039}
1040
1041static struct sock *ping_get_next(struct seq_file *seq, struct sock *sk)
1042{
1043 struct ping_iter_state *state = seq->private;
1044 struct net *net = seq_file_net(seq);
1045
1046 do {
1047 sk = sk_nulls_next(sk);
1048 } while (sk && (!net_eq(sock_net(sk), net)));
1049
1050 if (!sk)
1051 return ping_get_first(seq, state->bucket + 1);
1052 return sk;
1053}
1054
1055static struct sock *ping_get_idx(struct seq_file *seq, loff_t pos)
1056{
1057 struct sock *sk = ping_get_first(seq, 0);
1058
1059 if (sk)
1060 while (pos && (sk = ping_get_next(seq, sk)) != NULL)
1061 --pos;
1062 return pos ? NULL : sk;
1063}
1064
1065void *ping_seq_start(struct seq_file *seq, loff_t *pos, sa_family_t family)
1066 __acquires(ping_table.lock)
1067{
1068 struct ping_iter_state *state = seq->private;
1069 state->bucket = 0;
1070 state->family = family;
1071
1072 read_lock_bh(&ping_table.lock);
1073
1074 return *pos ? ping_get_idx(seq, *pos-1) : SEQ_START_TOKEN;
1075}
1076EXPORT_SYMBOL_GPL(ping_seq_start);
1077
1078static void *ping_v4_seq_start(struct seq_file *seq, loff_t *pos)
1079{
1080 return ping_seq_start(seq, pos, AF_INET);
1081}
1082
1083void *ping_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1084{
1085 struct sock *sk;
1086
1087 if (v == SEQ_START_TOKEN)
1088 sk = ping_get_idx(seq, 0);
1089 else
1090 sk = ping_get_next(seq, v);
1091
1092 ++*pos;
1093 return sk;
1094}
1095EXPORT_SYMBOL_GPL(ping_seq_next);
1096
1097void ping_seq_stop(struct seq_file *seq, void *v)
1098 __releases(ping_table.lock)
1099{
1100 read_unlock_bh(&ping_table.lock);
1101}
1102EXPORT_SYMBOL_GPL(ping_seq_stop);
1103
1104static void ping_v4_format_sock(struct sock *sp, struct seq_file *f,
1105 int bucket)
1106{
1107 struct inet_sock *inet = inet_sk(sp);
1108 __be32 dest = inet->inet_daddr;
1109 __be32 src = inet->inet_rcv_saddr;
1110 __u16 destp = ntohs(inet->inet_dport);
1111 __u16 srcp = ntohs(inet->inet_sport);
1112
1113 seq_printf(f, "%5d: %08X:%04X %08X:%04X"
1114 " %02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %u",
1115 bucket, src, srcp, dest, destp, sp->sk_state,
1116 sk_wmem_alloc_get(sp),
1117 sk_rmem_alloc_get(sp),
1118 0, 0L, 0,
1119 from_kuid_munged(seq_user_ns(f), sock_i_uid(sp)),
1120 0, sock_i_ino(sp),
1121 refcount_read(&sp->sk_refcnt), sp,
1122 atomic_read(&sp->sk_drops));
1123}
1124
1125static int ping_v4_seq_show(struct seq_file *seq, void *v)
1126{
1127 seq_setwidth(seq, 127);
1128 if (v == SEQ_START_TOKEN)
1129 seq_puts(seq, " sl local_address rem_address st tx_queue "
1130 "rx_queue tr tm->when retrnsmt uid timeout "
1131 "inode ref pointer drops");
1132 else {
1133 struct ping_iter_state *state = seq->private;
1134
1135 ping_v4_format_sock(v, seq, state->bucket);
1136 }
1137 seq_pad(seq, '\n');
1138 return 0;
1139}
1140
1141static const struct seq_operations ping_v4_seq_ops = {
1142 .start = ping_v4_seq_start,
1143 .show = ping_v4_seq_show,
1144 .next = ping_seq_next,
1145 .stop = ping_seq_stop,
1146};
1147
1148static int __net_init ping_v4_proc_init_net(struct net *net)
1149{
1150 if (!proc_create_net("icmp", 0444, net->proc_net, &ping_v4_seq_ops,
1151 sizeof(struct ping_iter_state)))
1152 return -ENOMEM;
1153 return 0;
1154}
1155
1156static void __net_exit ping_v4_proc_exit_net(struct net *net)
1157{
1158 remove_proc_entry("icmp", net->proc_net);
1159}
1160
1161static struct pernet_operations ping_v4_net_ops = {
1162 .init = ping_v4_proc_init_net,
1163 .exit = ping_v4_proc_exit_net,
1164};
1165
1166int __init ping_proc_init(void)
1167{
1168 return register_pernet_subsys(&ping_v4_net_ops);
1169}
1170
1171void ping_proc_exit(void)
1172{
1173 unregister_pernet_subsys(&ping_v4_net_ops);
1174}
1175
1176#endif
1177
1178void __init ping_init(void)
1179{
1180 int i;
1181
1182 for (i = 0; i < PING_HTABLE_SIZE; i++)
1183 INIT_HLIST_NULLS_HEAD(&ping_table.hash[i], i);
1184 rwlock_init(&ping_table.lock);
1185}