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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/icmp.h>
37#include <net/protocol.h>
38#include <linux/skbuff.h>
39#include <linux/proc_fs.h>
40#include <linux/export.h>
41#include <net/sock.h>
42#include <net/ping.h>
43#include <net/udp.h>
44#include <net/route.h>
45#include <net/inet_common.h>
46#include <net/checksum.h>
47
48#if IS_ENABLED(CONFIG_IPV6)
49#include <linux/in6.h>
50#include <linux/icmpv6.h>
51#include <net/addrconf.h>
52#include <net/ipv6.h>
53#include <net/transp_v6.h>
54#endif
55
56struct ping_table {
57 struct hlist_nulls_head hash[PING_HTABLE_SIZE];
58 rwlock_t lock;
59};
60
61static struct ping_table ping_table;
62struct pingv6_ops pingv6_ops;
63EXPORT_SYMBOL_GPL(pingv6_ops);
64
65static u16 ping_port_rover;
66
67static inline u32 ping_hashfn(const struct net *net, u32 num, u32 mask)
68{
69 u32 res = (num + net_hash_mix(net)) & mask;
70
71 pr_debug("hash(%u) = %u\n", num, res);
72 return res;
73}
74EXPORT_SYMBOL_GPL(ping_hash);
75
76static inline struct hlist_nulls_head *ping_hashslot(struct ping_table *table,
77 struct net *net, unsigned int num)
78{
79 return &table->hash[ping_hashfn(net, num, PING_HTABLE_MASK)];
80}
81
82int ping_get_port(struct sock *sk, unsigned short ident)
83{
84 struct hlist_nulls_node *node;
85 struct hlist_nulls_head *hlist;
86 struct inet_sock *isk, *isk2;
87 struct sock *sk2 = NULL;
88
89 isk = inet_sk(sk);
90 write_lock_bh(&ping_table.lock);
91 if (ident == 0) {
92 u32 i;
93 u16 result = ping_port_rover + 1;
94
95 for (i = 0; i < (1L << 16); i++, result++) {
96 if (!result)
97 result++; /* avoid zero */
98 hlist = ping_hashslot(&ping_table, sock_net(sk),
99 result);
100 ping_portaddr_for_each_entry(sk2, node, hlist) {
101 isk2 = inet_sk(sk2);
102
103 if (isk2->inet_num == result)
104 goto next_port;
105 }
106
107 /* found */
108 ping_port_rover = ident = result;
109 break;
110next_port:
111 ;
112 }
113 if (i >= (1L << 16))
114 goto fail;
115 } else {
116 hlist = ping_hashslot(&ping_table, sock_net(sk), ident);
117 ping_portaddr_for_each_entry(sk2, node, hlist) {
118 isk2 = inet_sk(sk2);
119
120 /* BUG? Why is this reuse and not reuseaddr? ping.c
121 * doesn't turn off SO_REUSEADDR, and it doesn't expect
122 * that other ping processes can steal its packets.
123 */
124 if ((isk2->inet_num == ident) &&
125 (sk2 != sk) &&
126 (!sk2->sk_reuse || !sk->sk_reuse))
127 goto fail;
128 }
129 }
130
131 pr_debug("found port/ident = %d\n", ident);
132 isk->inet_num = ident;
133 if (sk_unhashed(sk)) {
134 pr_debug("was not hashed\n");
135 sock_hold(sk);
136 hlist_nulls_add_head(&sk->sk_nulls_node, hlist);
137 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
138 }
139 write_unlock_bh(&ping_table.lock);
140 return 0;
141
142fail:
143 write_unlock_bh(&ping_table.lock);
144 return 1;
145}
146EXPORT_SYMBOL_GPL(ping_get_port);
147
148int ping_hash(struct sock *sk)
149{
150 pr_debug("ping_hash(sk->port=%u)\n", inet_sk(sk)->inet_num);
151 BUG(); /* "Please do not press this button again." */
152
153 return 0;
154}
155
156void ping_unhash(struct sock *sk)
157{
158 struct inet_sock *isk = inet_sk(sk);
159 pr_debug("ping_unhash(isk=%p,isk->num=%u)\n", isk, isk->inet_num);
160 if (sk_hashed(sk)) {
161 write_lock_bh(&ping_table.lock);
162 hlist_nulls_del(&sk->sk_nulls_node);
163 sk_nulls_node_init(&sk->sk_nulls_node);
164 sock_put(sk);
165 isk->inet_num = 0;
166 isk->inet_sport = 0;
167 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
168 write_unlock_bh(&ping_table.lock);
169 }
170}
171EXPORT_SYMBOL_GPL(ping_unhash);
172
173static struct sock *ping_lookup(struct net *net, struct sk_buff *skb, u16 ident)
174{
175 struct hlist_nulls_head *hslot = ping_hashslot(&ping_table, net, ident);
176 struct sock *sk = NULL;
177 struct inet_sock *isk;
178 struct hlist_nulls_node *hnode;
179 int dif = skb->dev->ifindex;
180
181 if (skb->protocol == htons(ETH_P_IP)) {
182 pr_debug("try to find: num = %d, daddr = %pI4, dif = %d\n",
183 (int)ident, &ip_hdr(skb)->daddr, dif);
184#if IS_ENABLED(CONFIG_IPV6)
185 } else if (skb->protocol == htons(ETH_P_IPV6)) {
186 pr_debug("try to find: num = %d, daddr = %pI6c, dif = %d\n",
187 (int)ident, &ipv6_hdr(skb)->daddr, dif);
188#endif
189 }
190
191 read_lock_bh(&ping_table.lock);
192
193 ping_portaddr_for_each_entry(sk, hnode, hslot) {
194 isk = inet_sk(sk);
195
196 pr_debug("iterate\n");
197 if (isk->inet_num != ident)
198 continue;
199
200 if (skb->protocol == htons(ETH_P_IP) &&
201 sk->sk_family == AF_INET) {
202 pr_debug("found: %p: num=%d, daddr=%pI4, dif=%d\n", sk,
203 (int) isk->inet_num, &isk->inet_rcv_saddr,
204 sk->sk_bound_dev_if);
205
206 if (isk->inet_rcv_saddr &&
207 isk->inet_rcv_saddr != ip_hdr(skb)->daddr)
208 continue;
209#if IS_ENABLED(CONFIG_IPV6)
210 } else if (skb->protocol == htons(ETH_P_IPV6) &&
211 sk->sk_family == AF_INET6) {
212
213 pr_debug("found: %p: num=%d, daddr=%pI6c, dif=%d\n", sk,
214 (int) isk->inet_num,
215 &sk->sk_v6_rcv_saddr,
216 sk->sk_bound_dev_if);
217
218 if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr) &&
219 !ipv6_addr_equal(&sk->sk_v6_rcv_saddr,
220 &ipv6_hdr(skb)->daddr))
221 continue;
222#endif
223 } else {
224 continue;
225 }
226
227 if (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif)
228 continue;
229
230 sock_hold(sk);
231 goto exit;
232 }
233
234 sk = NULL;
235exit:
236 read_unlock_bh(&ping_table.lock);
237
238 return sk;
239}
240
241static void inet_get_ping_group_range_net(struct net *net, kgid_t *low,
242 kgid_t *high)
243{
244 kgid_t *data = net->ipv4.ping_group_range.range;
245 unsigned int seq;
246
247 do {
248 seq = read_seqbegin(&net->ipv4.ping_group_range.lock);
249
250 *low = data[0];
251 *high = data[1];
252 } while (read_seqretry(&net->ipv4.ping_group_range.lock, seq));
253}
254
255
256int ping_init_sock(struct sock *sk)
257{
258 struct net *net = sock_net(sk);
259 kgid_t group = current_egid();
260 struct group_info *group_info;
261 int i;
262 kgid_t low, high;
263 int ret = 0;
264
265 if (sk->sk_family == AF_INET6)
266 sk->sk_ipv6only = 1;
267
268 inet_get_ping_group_range_net(net, &low, &high);
269 if (gid_lte(low, group) && gid_lte(group, high))
270 return 0;
271
272 group_info = get_current_groups();
273 for (i = 0; i < group_info->ngroups; i++) {
274 kgid_t gid = group_info->gid[i];
275
276 if (gid_lte(low, gid) && gid_lte(gid, high))
277 goto out_release_group;
278 }
279
280 ret = -EACCES;
281
282out_release_group:
283 put_group_info(group_info);
284 return ret;
285}
286EXPORT_SYMBOL_GPL(ping_init_sock);
287
288void ping_close(struct sock *sk, long timeout)
289{
290 pr_debug("ping_close(sk=%p,sk->num=%u)\n",
291 inet_sk(sk), inet_sk(sk)->inet_num);
292 pr_debug("isk->refcnt = %d\n", sk->sk_refcnt.counter);
293
294 sk_common_release(sk);
295}
296EXPORT_SYMBOL_GPL(ping_close);
297
298/* Checks the bind address and possibly modifies sk->sk_bound_dev_if. */
299static int ping_check_bind_addr(struct sock *sk, struct inet_sock *isk,
300 struct sockaddr *uaddr, int addr_len) {
301 struct net *net = sock_net(sk);
302 if (sk->sk_family == AF_INET) {
303 struct sockaddr_in *addr = (struct sockaddr_in *) uaddr;
304 int chk_addr_ret;
305
306 if (addr_len < sizeof(*addr))
307 return -EINVAL;
308
309 if (addr->sin_family != AF_INET &&
310 !(addr->sin_family == AF_UNSPEC &&
311 addr->sin_addr.s_addr == htonl(INADDR_ANY)))
312 return -EAFNOSUPPORT;
313
314 pr_debug("ping_check_bind_addr(sk=%p,addr=%pI4,port=%d)\n",
315 sk, &addr->sin_addr.s_addr, ntohs(addr->sin_port));
316
317 chk_addr_ret = inet_addr_type(net, addr->sin_addr.s_addr);
318
319 if (addr->sin_addr.s_addr == htonl(INADDR_ANY))
320 chk_addr_ret = RTN_LOCAL;
321
322 if ((net->ipv4.sysctl_ip_nonlocal_bind == 0 &&
323 isk->freebind == 0 && isk->transparent == 0 &&
324 chk_addr_ret != RTN_LOCAL) ||
325 chk_addr_ret == RTN_MULTICAST ||
326 chk_addr_ret == RTN_BROADCAST)
327 return -EADDRNOTAVAIL;
328
329#if IS_ENABLED(CONFIG_IPV6)
330 } else if (sk->sk_family == AF_INET6) {
331 struct sockaddr_in6 *addr = (struct sockaddr_in6 *) uaddr;
332 int addr_type, scoped, has_addr;
333 struct net_device *dev = NULL;
334
335 if (addr_len < sizeof(*addr))
336 return -EINVAL;
337
338 if (addr->sin6_family != AF_INET6)
339 return -EAFNOSUPPORT;
340
341 pr_debug("ping_check_bind_addr(sk=%p,addr=%pI6c,port=%d)\n",
342 sk, addr->sin6_addr.s6_addr, ntohs(addr->sin6_port));
343
344 addr_type = ipv6_addr_type(&addr->sin6_addr);
345 scoped = __ipv6_addr_needs_scope_id(addr_type);
346 if ((addr_type != IPV6_ADDR_ANY &&
347 !(addr_type & IPV6_ADDR_UNICAST)) ||
348 (scoped && !addr->sin6_scope_id))
349 return -EINVAL;
350
351 rcu_read_lock();
352 if (addr->sin6_scope_id) {
353 dev = dev_get_by_index_rcu(net, addr->sin6_scope_id);
354 if (!dev) {
355 rcu_read_unlock();
356 return -ENODEV;
357 }
358 }
359 has_addr = pingv6_ops.ipv6_chk_addr(net, &addr->sin6_addr, dev,
360 scoped);
361 rcu_read_unlock();
362
363 if (!(net->ipv6.sysctl.ip_nonlocal_bind ||
364 isk->freebind || isk->transparent || has_addr ||
365 addr_type == IPV6_ADDR_ANY))
366 return -EADDRNOTAVAIL;
367
368 if (scoped)
369 sk->sk_bound_dev_if = addr->sin6_scope_id;
370#endif
371 } else {
372 return -EAFNOSUPPORT;
373 }
374 return 0;
375}
376
377static void ping_set_saddr(struct sock *sk, struct sockaddr *saddr)
378{
379 if (saddr->sa_family == AF_INET) {
380 struct inet_sock *isk = inet_sk(sk);
381 struct sockaddr_in *addr = (struct sockaddr_in *) saddr;
382 isk->inet_rcv_saddr = isk->inet_saddr = addr->sin_addr.s_addr;
383#if IS_ENABLED(CONFIG_IPV6)
384 } else if (saddr->sa_family == AF_INET6) {
385 struct sockaddr_in6 *addr = (struct sockaddr_in6 *) saddr;
386 struct ipv6_pinfo *np = inet6_sk(sk);
387 sk->sk_v6_rcv_saddr = np->saddr = addr->sin6_addr;
388#endif
389 }
390}
391
392static void ping_clear_saddr(struct sock *sk, int dif)
393{
394 sk->sk_bound_dev_if = dif;
395 if (sk->sk_family == AF_INET) {
396 struct inet_sock *isk = inet_sk(sk);
397 isk->inet_rcv_saddr = isk->inet_saddr = 0;
398#if IS_ENABLED(CONFIG_IPV6)
399 } else if (sk->sk_family == AF_INET6) {
400 struct ipv6_pinfo *np = inet6_sk(sk);
401 memset(&sk->sk_v6_rcv_saddr, 0, sizeof(sk->sk_v6_rcv_saddr));
402 memset(&np->saddr, 0, sizeof(np->saddr));
403#endif
404 }
405}
406/*
407 * We need our own bind because there are no privileged id's == local ports.
408 * Moreover, we don't allow binding to multi- and broadcast addresses.
409 */
410
411int ping_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len)
412{
413 struct inet_sock *isk = inet_sk(sk);
414 unsigned short snum;
415 int err;
416 int dif = sk->sk_bound_dev_if;
417
418 err = ping_check_bind_addr(sk, isk, uaddr, addr_len);
419 if (err)
420 return err;
421
422 lock_sock(sk);
423
424 err = -EINVAL;
425 if (isk->inet_num != 0)
426 goto out;
427
428 err = -EADDRINUSE;
429 ping_set_saddr(sk, uaddr);
430 snum = ntohs(((struct sockaddr_in *)uaddr)->sin_port);
431 if (ping_get_port(sk, snum) != 0) {
432 ping_clear_saddr(sk, dif);
433 goto out;
434 }
435
436 pr_debug("after bind(): num = %d, dif = %d\n",
437 (int)isk->inet_num,
438 (int)sk->sk_bound_dev_if);
439
440 err = 0;
441 if (sk->sk_family == AF_INET && isk->inet_rcv_saddr)
442 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
443#if IS_ENABLED(CONFIG_IPV6)
444 if (sk->sk_family == AF_INET6 && !ipv6_addr_any(&sk->sk_v6_rcv_saddr))
445 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
446#endif
447
448 if (snum)
449 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
450 isk->inet_sport = htons(isk->inet_num);
451 isk->inet_daddr = 0;
452 isk->inet_dport = 0;
453
454#if IS_ENABLED(CONFIG_IPV6)
455 if (sk->sk_family == AF_INET6)
456 memset(&sk->sk_v6_daddr, 0, sizeof(sk->sk_v6_daddr));
457#endif
458
459 sk_dst_reset(sk);
460out:
461 release_sock(sk);
462 pr_debug("ping_v4_bind -> %d\n", err);
463 return err;
464}
465EXPORT_SYMBOL_GPL(ping_bind);
466
467/*
468 * Is this a supported type of ICMP message?
469 */
470
471static inline int ping_supported(int family, int type, int code)
472{
473 return (family == AF_INET && type == ICMP_ECHO && code == 0) ||
474 (family == AF_INET6 && type == ICMPV6_ECHO_REQUEST && code == 0);
475}
476
477/*
478 * This routine is called by the ICMP module when it gets some
479 * sort of error condition.
480 */
481
482void ping_err(struct sk_buff *skb, int offset, u32 info)
483{
484 int family;
485 struct icmphdr *icmph;
486 struct inet_sock *inet_sock;
487 int type;
488 int code;
489 struct net *net = dev_net(skb->dev);
490 struct sock *sk;
491 int harderr;
492 int err;
493
494 if (skb->protocol == htons(ETH_P_IP)) {
495 family = AF_INET;
496 type = icmp_hdr(skb)->type;
497 code = icmp_hdr(skb)->code;
498 icmph = (struct icmphdr *)(skb->data + offset);
499 } else if (skb->protocol == htons(ETH_P_IPV6)) {
500 family = AF_INET6;
501 type = icmp6_hdr(skb)->icmp6_type;
502 code = icmp6_hdr(skb)->icmp6_code;
503 icmph = (struct icmphdr *) (skb->data + offset);
504 } else {
505 BUG();
506 }
507
508 /* We assume the packet has already been checked by icmp_unreach */
509
510 if (!ping_supported(family, icmph->type, icmph->code))
511 return;
512
513 pr_debug("ping_err(proto=0x%x,type=%d,code=%d,id=%04x,seq=%04x)\n",
514 skb->protocol, type, code, ntohs(icmph->un.echo.id),
515 ntohs(icmph->un.echo.sequence));
516
517 sk = ping_lookup(net, skb, ntohs(icmph->un.echo.id));
518 if (!sk) {
519 pr_debug("no socket, dropping\n");
520 return; /* No socket for error */
521 }
522 pr_debug("err on socket %p\n", sk);
523
524 err = 0;
525 harderr = 0;
526 inet_sock = inet_sk(sk);
527
528 if (skb->protocol == htons(ETH_P_IP)) {
529 switch (type) {
530 default:
531 case ICMP_TIME_EXCEEDED:
532 err = EHOSTUNREACH;
533 break;
534 case ICMP_SOURCE_QUENCH:
535 /* This is not a real error but ping wants to see it.
536 * Report it with some fake errno.
537 */
538 err = EREMOTEIO;
539 break;
540 case ICMP_PARAMETERPROB:
541 err = EPROTO;
542 harderr = 1;
543 break;
544 case ICMP_DEST_UNREACH:
545 if (code == ICMP_FRAG_NEEDED) { /* Path MTU discovery */
546 ipv4_sk_update_pmtu(skb, sk, info);
547 if (inet_sock->pmtudisc != IP_PMTUDISC_DONT) {
548 err = EMSGSIZE;
549 harderr = 1;
550 break;
551 }
552 goto out;
553 }
554 err = EHOSTUNREACH;
555 if (code <= NR_ICMP_UNREACH) {
556 harderr = icmp_err_convert[code].fatal;
557 err = icmp_err_convert[code].errno;
558 }
559 break;
560 case ICMP_REDIRECT:
561 /* See ICMP_SOURCE_QUENCH */
562 ipv4_sk_redirect(skb, sk);
563 err = EREMOTEIO;
564 break;
565 }
566#if IS_ENABLED(CONFIG_IPV6)
567 } else if (skb->protocol == htons(ETH_P_IPV6)) {
568 harderr = pingv6_ops.icmpv6_err_convert(type, code, &err);
569#endif
570 }
571
572 /*
573 * RFC1122: OK. Passes ICMP errors back to application, as per
574 * 4.1.3.3.
575 */
576 if ((family == AF_INET && !inet_sock->recverr) ||
577 (family == AF_INET6 && !inet6_sk(sk)->recverr)) {
578 if (!harderr || sk->sk_state != TCP_ESTABLISHED)
579 goto out;
580 } else {
581 if (family == AF_INET) {
582 ip_icmp_error(sk, skb, err, 0 /* no remote port */,
583 info, (u8 *)icmph);
584#if IS_ENABLED(CONFIG_IPV6)
585 } else if (family == AF_INET6) {
586 pingv6_ops.ipv6_icmp_error(sk, skb, err, 0,
587 info, (u8 *)icmph);
588#endif
589 }
590 }
591 sk->sk_err = err;
592 sk->sk_error_report(sk);
593out:
594 sock_put(sk);
595}
596EXPORT_SYMBOL_GPL(ping_err);
597
598/*
599 * Copy and checksum an ICMP Echo packet from user space into a buffer
600 * starting from the payload.
601 */
602
603int ping_getfrag(void *from, char *to,
604 int offset, int fraglen, int odd, struct sk_buff *skb)
605{
606 struct pingfakehdr *pfh = (struct pingfakehdr *)from;
607
608 if (offset == 0) {
609 fraglen -= sizeof(struct icmphdr);
610 if (fraglen < 0)
611 BUG();
612 if (!csum_and_copy_from_iter_full(to + sizeof(struct icmphdr),
613 fraglen, &pfh->wcheck,
614 &pfh->msg->msg_iter))
615 return -EFAULT;
616 } else if (offset < sizeof(struct icmphdr)) {
617 BUG();
618 } else {
619 if (!csum_and_copy_from_iter_full(to, fraglen, &pfh->wcheck,
620 &pfh->msg->msg_iter))
621 return -EFAULT;
622 }
623
624#if IS_ENABLED(CONFIG_IPV6)
625 /* For IPv6, checksum each skb as we go along, as expected by
626 * icmpv6_push_pending_frames. For IPv4, accumulate the checksum in
627 * wcheck, it will be finalized in ping_v4_push_pending_frames.
628 */
629 if (pfh->family == AF_INET6) {
630 skb->csum = pfh->wcheck;
631 skb->ip_summed = CHECKSUM_NONE;
632 pfh->wcheck = 0;
633 }
634#endif
635
636 return 0;
637}
638EXPORT_SYMBOL_GPL(ping_getfrag);
639
640static int ping_v4_push_pending_frames(struct sock *sk, struct pingfakehdr *pfh,
641 struct flowi4 *fl4)
642{
643 struct sk_buff *skb = skb_peek(&sk->sk_write_queue);
644
645 if (!skb)
646 return 0;
647 pfh->wcheck = csum_partial((char *)&pfh->icmph,
648 sizeof(struct icmphdr), pfh->wcheck);
649 pfh->icmph.checksum = csum_fold(pfh->wcheck);
650 memcpy(icmp_hdr(skb), &pfh->icmph, sizeof(struct icmphdr));
651 skb->ip_summed = CHECKSUM_NONE;
652 return ip_push_pending_frames(sk, fl4);
653}
654
655int ping_common_sendmsg(int family, struct msghdr *msg, size_t len,
656 void *user_icmph, size_t icmph_len) {
657 u8 type, code;
658
659 if (len > 0xFFFF)
660 return -EMSGSIZE;
661
662 /* Must have at least a full ICMP header. */
663 if (len < icmph_len)
664 return -EINVAL;
665
666 /*
667 * Check the flags.
668 */
669
670 /* Mirror BSD error message compatibility */
671 if (msg->msg_flags & MSG_OOB)
672 return -EOPNOTSUPP;
673
674 /*
675 * Fetch the ICMP header provided by the userland.
676 * iovec is modified! The ICMP header is consumed.
677 */
678 if (memcpy_from_msg(user_icmph, msg, icmph_len))
679 return -EFAULT;
680
681 if (family == AF_INET) {
682 type = ((struct icmphdr *) user_icmph)->type;
683 code = ((struct icmphdr *) user_icmph)->code;
684#if IS_ENABLED(CONFIG_IPV6)
685 } else if (family == AF_INET6) {
686 type = ((struct icmp6hdr *) user_icmph)->icmp6_type;
687 code = ((struct icmp6hdr *) user_icmph)->icmp6_code;
688#endif
689 } else {
690 BUG();
691 }
692
693 if (!ping_supported(family, type, code))
694 return -EINVAL;
695
696 return 0;
697}
698EXPORT_SYMBOL_GPL(ping_common_sendmsg);
699
700static int ping_v4_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
701{
702 struct net *net = sock_net(sk);
703 struct flowi4 fl4;
704 struct inet_sock *inet = inet_sk(sk);
705 struct ipcm_cookie ipc;
706 struct icmphdr user_icmph;
707 struct pingfakehdr pfh;
708 struct rtable *rt = NULL;
709 struct ip_options_data opt_copy;
710 int free = 0;
711 __be32 saddr, daddr, faddr;
712 u8 tos;
713 int err;
714
715 pr_debug("ping_v4_sendmsg(sk=%p,sk->num=%u)\n", inet, inet->inet_num);
716
717 err = ping_common_sendmsg(AF_INET, msg, len, &user_icmph,
718 sizeof(user_icmph));
719 if (err)
720 return err;
721
722 /*
723 * Get and verify the address.
724 */
725
726 if (msg->msg_name) {
727 DECLARE_SOCKADDR(struct sockaddr_in *, usin, msg->msg_name);
728 if (msg->msg_namelen < sizeof(*usin))
729 return -EINVAL;
730 if (usin->sin_family != AF_INET)
731 return -EAFNOSUPPORT;
732 daddr = usin->sin_addr.s_addr;
733 /* no remote port */
734 } else {
735 if (sk->sk_state != TCP_ESTABLISHED)
736 return -EDESTADDRREQ;
737 daddr = inet->inet_daddr;
738 /* no remote port */
739 }
740
741 ipc.sockc.tsflags = sk->sk_tsflags;
742 ipc.addr = inet->inet_saddr;
743 ipc.opt = NULL;
744 ipc.oif = sk->sk_bound_dev_if;
745 ipc.tx_flags = 0;
746 ipc.ttl = 0;
747 ipc.tos = -1;
748
749 if (msg->msg_controllen) {
750 err = ip_cmsg_send(sk, msg, &ipc, false);
751 if (unlikely(err)) {
752 kfree(ipc.opt);
753 return err;
754 }
755 if (ipc.opt)
756 free = 1;
757 }
758 if (!ipc.opt) {
759 struct ip_options_rcu *inet_opt;
760
761 rcu_read_lock();
762 inet_opt = rcu_dereference(inet->inet_opt);
763 if (inet_opt) {
764 memcpy(&opt_copy, inet_opt,
765 sizeof(*inet_opt) + inet_opt->opt.optlen);
766 ipc.opt = &opt_copy.opt;
767 }
768 rcu_read_unlock();
769 }
770
771 sock_tx_timestamp(sk, ipc.sockc.tsflags, &ipc.tx_flags);
772
773 saddr = ipc.addr;
774 ipc.addr = faddr = daddr;
775
776 if (ipc.opt && ipc.opt->opt.srr) {
777 if (!daddr)
778 return -EINVAL;
779 faddr = ipc.opt->opt.faddr;
780 }
781 tos = get_rttos(&ipc, inet);
782 if (sock_flag(sk, SOCK_LOCALROUTE) ||
783 (msg->msg_flags & MSG_DONTROUTE) ||
784 (ipc.opt && ipc.opt->opt.is_strictroute)) {
785 tos |= RTO_ONLINK;
786 }
787
788 if (ipv4_is_multicast(daddr)) {
789 if (!ipc.oif)
790 ipc.oif = inet->mc_index;
791 if (!saddr)
792 saddr = inet->mc_addr;
793 } else if (!ipc.oif)
794 ipc.oif = inet->uc_index;
795
796 flowi4_init_output(&fl4, ipc.oif, sk->sk_mark, tos,
797 RT_SCOPE_UNIVERSE, sk->sk_protocol,
798 inet_sk_flowi_flags(sk), faddr, saddr, 0, 0,
799 sk->sk_uid);
800
801 security_sk_classify_flow(sk, flowi4_to_flowi(&fl4));
802 rt = ip_route_output_flow(net, &fl4, sk);
803 if (IS_ERR(rt)) {
804 err = PTR_ERR(rt);
805 rt = NULL;
806 if (err == -ENETUNREACH)
807 IP_INC_STATS(net, IPSTATS_MIB_OUTNOROUTES);
808 goto out;
809 }
810
811 err = -EACCES;
812 if ((rt->rt_flags & RTCF_BROADCAST) &&
813 !sock_flag(sk, SOCK_BROADCAST))
814 goto out;
815
816 if (msg->msg_flags & MSG_CONFIRM)
817 goto do_confirm;
818back_from_confirm:
819
820 if (!ipc.addr)
821 ipc.addr = fl4.daddr;
822
823 lock_sock(sk);
824
825 pfh.icmph.type = user_icmph.type; /* already checked */
826 pfh.icmph.code = user_icmph.code; /* ditto */
827 pfh.icmph.checksum = 0;
828 pfh.icmph.un.echo.id = inet->inet_sport;
829 pfh.icmph.un.echo.sequence = user_icmph.un.echo.sequence;
830 pfh.msg = msg;
831 pfh.wcheck = 0;
832 pfh.family = AF_INET;
833
834 err = ip_append_data(sk, &fl4, ping_getfrag, &pfh, len,
835 0, &ipc, &rt, msg->msg_flags);
836 if (err)
837 ip_flush_pending_frames(sk);
838 else
839 err = ping_v4_push_pending_frames(sk, &pfh, &fl4);
840 release_sock(sk);
841
842out:
843 ip_rt_put(rt);
844 if (free)
845 kfree(ipc.opt);
846 if (!err) {
847 icmp_out_count(sock_net(sk), user_icmph.type);
848 return len;
849 }
850 return err;
851
852do_confirm:
853 dst_confirm(&rt->dst);
854 if (!(msg->msg_flags & MSG_PROBE) || len)
855 goto back_from_confirm;
856 err = 0;
857 goto out;
858}
859
860int ping_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int noblock,
861 int flags, int *addr_len)
862{
863 struct inet_sock *isk = inet_sk(sk);
864 int family = sk->sk_family;
865 struct sk_buff *skb;
866 int copied, err;
867
868 pr_debug("ping_recvmsg(sk=%p,sk->num=%u)\n", isk, isk->inet_num);
869
870 err = -EOPNOTSUPP;
871 if (flags & MSG_OOB)
872 goto out;
873
874 if (flags & MSG_ERRQUEUE)
875 return inet_recv_error(sk, msg, len, addr_len);
876
877 skb = skb_recv_datagram(sk, flags, noblock, &err);
878 if (!skb)
879 goto out;
880
881 copied = skb->len;
882 if (copied > len) {
883 msg->msg_flags |= MSG_TRUNC;
884 copied = len;
885 }
886
887 /* Don't bother checking the checksum */
888 err = skb_copy_datagram_msg(skb, 0, msg, copied);
889 if (err)
890 goto done;
891
892 sock_recv_timestamp(msg, sk, skb);
893
894 /* Copy the address and add cmsg data. */
895 if (family == AF_INET) {
896 DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name);
897
898 if (sin) {
899 sin->sin_family = AF_INET;
900 sin->sin_port = 0 /* skb->h.uh->source */;
901 sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
902 memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
903 *addr_len = sizeof(*sin);
904 }
905
906 if (isk->cmsg_flags)
907 ip_cmsg_recv(msg, skb);
908
909#if IS_ENABLED(CONFIG_IPV6)
910 } else if (family == AF_INET6) {
911 struct ipv6_pinfo *np = inet6_sk(sk);
912 struct ipv6hdr *ip6 = ipv6_hdr(skb);
913 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
914
915 if (sin6) {
916 sin6->sin6_family = AF_INET6;
917 sin6->sin6_port = 0;
918 sin6->sin6_addr = ip6->saddr;
919 sin6->sin6_flowinfo = 0;
920 if (np->sndflow)
921 sin6->sin6_flowinfo = ip6_flowinfo(ip6);
922 sin6->sin6_scope_id =
923 ipv6_iface_scope_id(&sin6->sin6_addr,
924 inet6_iif(skb));
925 *addr_len = sizeof(*sin6);
926 }
927
928 if (inet6_sk(sk)->rxopt.all)
929 pingv6_ops.ip6_datagram_recv_common_ctl(sk, msg, skb);
930 if (skb->protocol == htons(ETH_P_IPV6) &&
931 inet6_sk(sk)->rxopt.all)
932 pingv6_ops.ip6_datagram_recv_specific_ctl(sk, msg, skb);
933 else if (skb->protocol == htons(ETH_P_IP) && isk->cmsg_flags)
934 ip_cmsg_recv(msg, skb);
935#endif
936 } else {
937 BUG();
938 }
939
940 err = copied;
941
942done:
943 skb_free_datagram(sk, skb);
944out:
945 pr_debug("ping_recvmsg -> %d\n", err);
946 return err;
947}
948EXPORT_SYMBOL_GPL(ping_recvmsg);
949
950int ping_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
951{
952 pr_debug("ping_queue_rcv_skb(sk=%p,sk->num=%d,skb=%p)\n",
953 inet_sk(sk), inet_sk(sk)->inet_num, skb);
954 if (sock_queue_rcv_skb(sk, skb) < 0) {
955 kfree_skb(skb);
956 pr_debug("ping_queue_rcv_skb -> failed\n");
957 return -1;
958 }
959 return 0;
960}
961EXPORT_SYMBOL_GPL(ping_queue_rcv_skb);
962
963
964/*
965 * All we need to do is get the socket.
966 */
967
968bool ping_rcv(struct sk_buff *skb)
969{
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 ping_queue_rcv_skb(sk, skb2);
989 sock_put(sk);
990 return true;
991 }
992 pr_debug("no socket, dropping\n");
993
994 return false;
995}
996EXPORT_SYMBOL_GPL(ping_rcv);
997
998struct proto ping_prot = {
999 .name = "PING",
1000 .owner = THIS_MODULE,
1001 .init = ping_init_sock,
1002 .close = ping_close,
1003 .connect = ip4_datagram_connect,
1004 .disconnect = __udp_disconnect,
1005 .setsockopt = ip_setsockopt,
1006 .getsockopt = ip_getsockopt,
1007 .sendmsg = ping_v4_sendmsg,
1008 .recvmsg = ping_recvmsg,
1009 .bind = ping_bind,
1010 .backlog_rcv = ping_queue_rcv_skb,
1011 .release_cb = ip4_datagram_release_cb,
1012 .hash = ping_hash,
1013 .unhash = ping_unhash,
1014 .get_port = ping_get_port,
1015 .obj_size = sizeof(struct inet_sock),
1016};
1017EXPORT_SYMBOL(ping_prot);
1018
1019#ifdef CONFIG_PROC_FS
1020
1021static struct sock *ping_get_first(struct seq_file *seq, int start)
1022{
1023 struct sock *sk;
1024 struct ping_iter_state *state = seq->private;
1025 struct net *net = seq_file_net(seq);
1026
1027 for (state->bucket = start; state->bucket < PING_HTABLE_SIZE;
1028 ++state->bucket) {
1029 struct hlist_nulls_node *node;
1030 struct hlist_nulls_head *hslot;
1031
1032 hslot = &ping_table.hash[state->bucket];
1033
1034 if (hlist_nulls_empty(hslot))
1035 continue;
1036
1037 sk_nulls_for_each(sk, node, hslot) {
1038 if (net_eq(sock_net(sk), net) &&
1039 sk->sk_family == state->family)
1040 goto found;
1041 }
1042 }
1043 sk = NULL;
1044found:
1045 return sk;
1046}
1047
1048static struct sock *ping_get_next(struct seq_file *seq, struct sock *sk)
1049{
1050 struct ping_iter_state *state = seq->private;
1051 struct net *net = seq_file_net(seq);
1052
1053 do {
1054 sk = sk_nulls_next(sk);
1055 } while (sk && (!net_eq(sock_net(sk), net)));
1056
1057 if (!sk)
1058 return ping_get_first(seq, state->bucket + 1);
1059 return sk;
1060}
1061
1062static struct sock *ping_get_idx(struct seq_file *seq, loff_t pos)
1063{
1064 struct sock *sk = ping_get_first(seq, 0);
1065
1066 if (sk)
1067 while (pos && (sk = ping_get_next(seq, sk)) != NULL)
1068 --pos;
1069 return pos ? NULL : sk;
1070}
1071
1072void *ping_seq_start(struct seq_file *seq, loff_t *pos, sa_family_t family)
1073 __acquires(ping_table.lock)
1074{
1075 struct ping_iter_state *state = seq->private;
1076 state->bucket = 0;
1077 state->family = family;
1078
1079 read_lock_bh(&ping_table.lock);
1080
1081 return *pos ? ping_get_idx(seq, *pos-1) : SEQ_START_TOKEN;
1082}
1083EXPORT_SYMBOL_GPL(ping_seq_start);
1084
1085static void *ping_v4_seq_start(struct seq_file *seq, loff_t *pos)
1086{
1087 return ping_seq_start(seq, pos, AF_INET);
1088}
1089
1090void *ping_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1091{
1092 struct sock *sk;
1093
1094 if (v == SEQ_START_TOKEN)
1095 sk = ping_get_idx(seq, 0);
1096 else
1097 sk = ping_get_next(seq, v);
1098
1099 ++*pos;
1100 return sk;
1101}
1102EXPORT_SYMBOL_GPL(ping_seq_next);
1103
1104void ping_seq_stop(struct seq_file *seq, void *v)
1105 __releases(ping_table.lock)
1106{
1107 read_unlock_bh(&ping_table.lock);
1108}
1109EXPORT_SYMBOL_GPL(ping_seq_stop);
1110
1111static void ping_v4_format_sock(struct sock *sp, struct seq_file *f,
1112 int bucket)
1113{
1114 struct inet_sock *inet = inet_sk(sp);
1115 __be32 dest = inet->inet_daddr;
1116 __be32 src = inet->inet_rcv_saddr;
1117 __u16 destp = ntohs(inet->inet_dport);
1118 __u16 srcp = ntohs(inet->inet_sport);
1119
1120 seq_printf(f, "%5d: %08X:%04X %08X:%04X"
1121 " %02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %d",
1122 bucket, src, srcp, dest, destp, sp->sk_state,
1123 sk_wmem_alloc_get(sp),
1124 sk_rmem_alloc_get(sp),
1125 0, 0L, 0,
1126 from_kuid_munged(seq_user_ns(f), sock_i_uid(sp)),
1127 0, sock_i_ino(sp),
1128 atomic_read(&sp->sk_refcnt), sp,
1129 atomic_read(&sp->sk_drops));
1130}
1131
1132static int ping_v4_seq_show(struct seq_file *seq, void *v)
1133{
1134 seq_setwidth(seq, 127);
1135 if (v == SEQ_START_TOKEN)
1136 seq_puts(seq, " sl local_address rem_address st tx_queue "
1137 "rx_queue tr tm->when retrnsmt uid timeout "
1138 "inode ref pointer drops");
1139 else {
1140 struct ping_iter_state *state = seq->private;
1141
1142 ping_v4_format_sock(v, seq, state->bucket);
1143 }
1144 seq_pad(seq, '\n');
1145 return 0;
1146}
1147
1148static int ping_seq_open(struct inode *inode, struct file *file)
1149{
1150 struct ping_seq_afinfo *afinfo = PDE_DATA(inode);
1151 return seq_open_net(inode, file, &afinfo->seq_ops,
1152 sizeof(struct ping_iter_state));
1153}
1154
1155const struct file_operations ping_seq_fops = {
1156 .open = ping_seq_open,
1157 .read = seq_read,
1158 .llseek = seq_lseek,
1159 .release = seq_release_net,
1160};
1161EXPORT_SYMBOL_GPL(ping_seq_fops);
1162
1163static struct ping_seq_afinfo ping_v4_seq_afinfo = {
1164 .name = "icmp",
1165 .family = AF_INET,
1166 .seq_fops = &ping_seq_fops,
1167 .seq_ops = {
1168 .start = ping_v4_seq_start,
1169 .show = ping_v4_seq_show,
1170 .next = ping_seq_next,
1171 .stop = ping_seq_stop,
1172 },
1173};
1174
1175int ping_proc_register(struct net *net, struct ping_seq_afinfo *afinfo)
1176{
1177 struct proc_dir_entry *p;
1178 p = proc_create_data(afinfo->name, S_IRUGO, net->proc_net,
1179 afinfo->seq_fops, afinfo);
1180 if (!p)
1181 return -ENOMEM;
1182 return 0;
1183}
1184EXPORT_SYMBOL_GPL(ping_proc_register);
1185
1186void ping_proc_unregister(struct net *net, struct ping_seq_afinfo *afinfo)
1187{
1188 remove_proc_entry(afinfo->name, net->proc_net);
1189}
1190EXPORT_SYMBOL_GPL(ping_proc_unregister);
1191
1192static int __net_init ping_v4_proc_init_net(struct net *net)
1193{
1194 return ping_proc_register(net, &ping_v4_seq_afinfo);
1195}
1196
1197static void __net_exit ping_v4_proc_exit_net(struct net *net)
1198{
1199 ping_proc_unregister(net, &ping_v4_seq_afinfo);
1200}
1201
1202static struct pernet_operations ping_v4_net_ops = {
1203 .init = ping_v4_proc_init_net,
1204 .exit = ping_v4_proc_exit_net,
1205};
1206
1207int __init ping_proc_init(void)
1208{
1209 return register_pernet_subsys(&ping_v4_net_ops);
1210}
1211
1212void ping_proc_exit(void)
1213{
1214 unregister_pernet_subsys(&ping_v4_net_ops);
1215}
1216
1217#endif
1218
1219void __init ping_init(void)
1220{
1221 int i;
1222
1223 for (i = 0; i < PING_HTABLE_SIZE; i++)
1224 INIT_HLIST_NULLS_HEAD(&ping_table.hash[i], i);
1225 rwlock_init(&ping_table.lock);
1226}