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1/*
2 * INET An implementation of the TCP/IP protocol suite for the LINUX
3 * operating system. INET is implemented using the BSD Socket
4 * interface as the means of communication with the user level.
5 *
6 * "Ping" sockets
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * as published by the Free Software Foundation; either version
11 * 2 of the License, or (at your option) any later version.
12 *
13 * Based on ipv4/udp.c code.
14 *
15 * Authors: Vasiliy Kulikov / Openwall (for Linux 2.6),
16 * Pavel Kankovsky (for Linux 2.4.32)
17 *
18 * Pavel gave all rights to bugs to Vasiliy,
19 * none of the bugs are Pavel's now.
20 *
21 */
22
23#include <linux/uaccess.h>
24#include <linux/types.h>
25#include <linux/fcntl.h>
26#include <linux/socket.h>
27#include <linux/sockios.h>
28#include <linux/in.h>
29#include <linux/errno.h>
30#include <linux/timer.h>
31#include <linux/mm.h>
32#include <linux/inet.h>
33#include <linux/netdevice.h>
34#include <net/snmp.h>
35#include <net/ip.h>
36#include <net/icmp.h>
37#include <net/protocol.h>
38#include <linux/skbuff.h>
39#include <linux/proc_fs.h>
40#include <linux/export.h>
41#include <net/sock.h>
42#include <net/ping.h>
43#include <net/udp.h>
44#include <net/route.h>
45#include <net/inet_common.h>
46#include <net/checksum.h>
47
48#if IS_ENABLED(CONFIG_IPV6)
49#include <linux/in6.h>
50#include <linux/icmpv6.h>
51#include <net/addrconf.h>
52#include <net/ipv6.h>
53#include <net/transp_v6.h>
54#endif
55
56struct ping_table {
57 struct hlist_nulls_head hash[PING_HTABLE_SIZE];
58 rwlock_t lock;
59};
60
61static struct ping_table ping_table;
62struct pingv6_ops pingv6_ops;
63EXPORT_SYMBOL_GPL(pingv6_ops);
64
65static u16 ping_port_rover;
66
67static inline int ping_hashfn(struct net *net, unsigned int num, unsigned int mask)
68{
69 int res = (num + net_hash_mix(net)) & mask;
70
71 pr_debug("hash(%d) = %d\n", num, res);
72 return res;
73}
74EXPORT_SYMBOL_GPL(ping_hash);
75
76static inline struct hlist_nulls_head *ping_hashslot(struct ping_table *table,
77 struct net *net, unsigned int num)
78{
79 return &table->hash[ping_hashfn(net, num, PING_HTABLE_MASK)];
80}
81
82int ping_get_port(struct sock *sk, unsigned short ident)
83{
84 struct hlist_nulls_node *node;
85 struct hlist_nulls_head *hlist;
86 struct inet_sock *isk, *isk2;
87 struct sock *sk2 = NULL;
88
89 isk = inet_sk(sk);
90 write_lock_bh(&ping_table.lock);
91 if (ident == 0) {
92 u32 i;
93 u16 result = ping_port_rover + 1;
94
95 for (i = 0; i < (1L << 16); i++, result++) {
96 if (!result)
97 result++; /* avoid zero */
98 hlist = ping_hashslot(&ping_table, sock_net(sk),
99 result);
100 ping_portaddr_for_each_entry(sk2, node, hlist) {
101 isk2 = inet_sk(sk2);
102
103 if (isk2->inet_num == result)
104 goto next_port;
105 }
106
107 /* found */
108 ping_port_rover = ident = result;
109 break;
110next_port:
111 ;
112 }
113 if (i >= (1L << 16))
114 goto fail;
115 } else {
116 hlist = ping_hashslot(&ping_table, sock_net(sk), ident);
117 ping_portaddr_for_each_entry(sk2, node, hlist) {
118 isk2 = inet_sk(sk2);
119
120 /* BUG? Why is this reuse and not reuseaddr? ping.c
121 * doesn't turn off SO_REUSEADDR, and it doesn't expect
122 * that other ping processes can steal its packets.
123 */
124 if ((isk2->inet_num == ident) &&
125 (sk2 != sk) &&
126 (!sk2->sk_reuse || !sk->sk_reuse))
127 goto fail;
128 }
129 }
130
131 pr_debug("found port/ident = %d\n", ident);
132 isk->inet_num = ident;
133 if (sk_unhashed(sk)) {
134 pr_debug("was not hashed\n");
135 sock_hold(sk);
136 hlist_nulls_add_head(&sk->sk_nulls_node, hlist);
137 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
138 }
139 write_unlock_bh(&ping_table.lock);
140 return 0;
141
142fail:
143 write_unlock_bh(&ping_table.lock);
144 return 1;
145}
146EXPORT_SYMBOL_GPL(ping_get_port);
147
148void ping_hash(struct sock *sk)
149{
150 pr_debug("ping_hash(sk->port=%u)\n", inet_sk(sk)->inet_num);
151 BUG(); /* "Please do not press this button again." */
152}
153
154void ping_unhash(struct sock *sk)
155{
156 struct inet_sock *isk = inet_sk(sk);
157 pr_debug("ping_unhash(isk=%p,isk->num=%u)\n", isk, isk->inet_num);
158 if (sk_hashed(sk)) {
159 write_lock_bh(&ping_table.lock);
160 hlist_nulls_del(&sk->sk_nulls_node);
161 sock_put(sk);
162 isk->inet_num = 0;
163 isk->inet_sport = 0;
164 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
165 write_unlock_bh(&ping_table.lock);
166 }
167}
168EXPORT_SYMBOL_GPL(ping_unhash);
169
170static struct sock *ping_lookup(struct net *net, struct sk_buff *skb, u16 ident)
171{
172 struct hlist_nulls_head *hslot = ping_hashslot(&ping_table, net, ident);
173 struct sock *sk = NULL;
174 struct inet_sock *isk;
175 struct hlist_nulls_node *hnode;
176 int dif = skb->dev->ifindex;
177
178 if (skb->protocol == htons(ETH_P_IP)) {
179 pr_debug("try to find: num = %d, daddr = %pI4, dif = %d\n",
180 (int)ident, &ip_hdr(skb)->daddr, dif);
181#if IS_ENABLED(CONFIG_IPV6)
182 } else if (skb->protocol == htons(ETH_P_IPV6)) {
183 pr_debug("try to find: num = %d, daddr = %pI6c, dif = %d\n",
184 (int)ident, &ipv6_hdr(skb)->daddr, dif);
185#endif
186 }
187
188 read_lock_bh(&ping_table.lock);
189
190 ping_portaddr_for_each_entry(sk, hnode, hslot) {
191 isk = inet_sk(sk);
192
193 pr_debug("iterate\n");
194 if (isk->inet_num != ident)
195 continue;
196
197 if (skb->protocol == htons(ETH_P_IP) &&
198 sk->sk_family == AF_INET) {
199 pr_debug("found: %p: num=%d, daddr=%pI4, dif=%d\n", sk,
200 (int) isk->inet_num, &isk->inet_rcv_saddr,
201 sk->sk_bound_dev_if);
202
203 if (isk->inet_rcv_saddr &&
204 isk->inet_rcv_saddr != ip_hdr(skb)->daddr)
205 continue;
206#if IS_ENABLED(CONFIG_IPV6)
207 } else if (skb->protocol == htons(ETH_P_IPV6) &&
208 sk->sk_family == AF_INET6) {
209
210 pr_debug("found: %p: num=%d, daddr=%pI6c, dif=%d\n", sk,
211 (int) isk->inet_num,
212 &sk->sk_v6_rcv_saddr,
213 sk->sk_bound_dev_if);
214
215 if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr) &&
216 !ipv6_addr_equal(&sk->sk_v6_rcv_saddr,
217 &ipv6_hdr(skb)->daddr))
218 continue;
219#endif
220 }
221
222 if (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif)
223 continue;
224
225 sock_hold(sk);
226 goto exit;
227 }
228
229 sk = NULL;
230exit:
231 read_unlock_bh(&ping_table.lock);
232
233 return sk;
234}
235
236static void inet_get_ping_group_range_net(struct net *net, kgid_t *low,
237 kgid_t *high)
238{
239 kgid_t *data = net->ipv4.ping_group_range.range;
240 unsigned int seq;
241
242 do {
243 seq = read_seqbegin(&net->ipv4.ping_group_range.lock);
244
245 *low = data[0];
246 *high = data[1];
247 } while (read_seqretry(&net->ipv4.ping_group_range.lock, seq));
248}
249
250
251int ping_init_sock(struct sock *sk)
252{
253 struct net *net = sock_net(sk);
254 kgid_t group = current_egid();
255 struct group_info *group_info;
256 int i, j, count;
257 kgid_t low, high;
258 int ret = 0;
259
260 inet_get_ping_group_range_net(net, &low, &high);
261 if (gid_lte(low, group) && gid_lte(group, high))
262 return 0;
263
264 group_info = get_current_groups();
265 count = group_info->ngroups;
266 for (i = 0; i < group_info->nblocks; i++) {
267 int cp_count = min_t(int, NGROUPS_PER_BLOCK, count);
268 for (j = 0; j < cp_count; j++) {
269 kgid_t gid = group_info->blocks[i][j];
270 if (gid_lte(low, gid) && gid_lte(gid, high))
271 goto out_release_group;
272 }
273
274 count -= cp_count;
275 }
276
277 ret = -EACCES;
278
279out_release_group:
280 put_group_info(group_info);
281 return ret;
282}
283EXPORT_SYMBOL_GPL(ping_init_sock);
284
285void ping_close(struct sock *sk, long timeout)
286{
287 pr_debug("ping_close(sk=%p,sk->num=%u)\n",
288 inet_sk(sk), inet_sk(sk)->inet_num);
289 pr_debug("isk->refcnt = %d\n", sk->sk_refcnt.counter);
290
291 sk_common_release(sk);
292}
293EXPORT_SYMBOL_GPL(ping_close);
294
295/* Checks the bind address and possibly modifies sk->sk_bound_dev_if. */
296static int ping_check_bind_addr(struct sock *sk, struct inet_sock *isk,
297 struct sockaddr *uaddr, int addr_len) {
298 struct net *net = sock_net(sk);
299 if (sk->sk_family == AF_INET) {
300 struct sockaddr_in *addr = (struct sockaddr_in *) uaddr;
301 int chk_addr_ret;
302
303 if (addr_len < sizeof(*addr))
304 return -EINVAL;
305
306 pr_debug("ping_check_bind_addr(sk=%p,addr=%pI4,port=%d)\n",
307 sk, &addr->sin_addr.s_addr, ntohs(addr->sin_port));
308
309 chk_addr_ret = inet_addr_type(net, addr->sin_addr.s_addr);
310
311 if (addr->sin_addr.s_addr == htonl(INADDR_ANY))
312 chk_addr_ret = RTN_LOCAL;
313
314 if ((sysctl_ip_nonlocal_bind == 0 &&
315 isk->freebind == 0 && isk->transparent == 0 &&
316 chk_addr_ret != RTN_LOCAL) ||
317 chk_addr_ret == RTN_MULTICAST ||
318 chk_addr_ret == RTN_BROADCAST)
319 return -EADDRNOTAVAIL;
320
321#if IS_ENABLED(CONFIG_IPV6)
322 } else if (sk->sk_family == AF_INET6) {
323 struct sockaddr_in6 *addr = (struct sockaddr_in6 *) uaddr;
324 int addr_type, scoped, has_addr;
325 struct net_device *dev = NULL;
326
327 if (addr_len < sizeof(*addr))
328 return -EINVAL;
329
330 if (addr->sin6_family != AF_INET6)
331 return -EINVAL;
332
333 pr_debug("ping_check_bind_addr(sk=%p,addr=%pI6c,port=%d)\n",
334 sk, addr->sin6_addr.s6_addr, ntohs(addr->sin6_port));
335
336 addr_type = ipv6_addr_type(&addr->sin6_addr);
337 scoped = __ipv6_addr_needs_scope_id(addr_type);
338 if ((addr_type != IPV6_ADDR_ANY &&
339 !(addr_type & IPV6_ADDR_UNICAST)) ||
340 (scoped && !addr->sin6_scope_id))
341 return -EINVAL;
342
343 rcu_read_lock();
344 if (addr->sin6_scope_id) {
345 dev = dev_get_by_index_rcu(net, addr->sin6_scope_id);
346 if (!dev) {
347 rcu_read_unlock();
348 return -ENODEV;
349 }
350 }
351 has_addr = pingv6_ops.ipv6_chk_addr(net, &addr->sin6_addr, dev,
352 scoped);
353 rcu_read_unlock();
354
355 if (!(isk->freebind || isk->transparent || has_addr ||
356 addr_type == IPV6_ADDR_ANY))
357 return -EADDRNOTAVAIL;
358
359 if (scoped)
360 sk->sk_bound_dev_if = addr->sin6_scope_id;
361#endif
362 } else {
363 return -EAFNOSUPPORT;
364 }
365 return 0;
366}
367
368static void ping_set_saddr(struct sock *sk, struct sockaddr *saddr)
369{
370 if (saddr->sa_family == AF_INET) {
371 struct inet_sock *isk = inet_sk(sk);
372 struct sockaddr_in *addr = (struct sockaddr_in *) saddr;
373 isk->inet_rcv_saddr = isk->inet_saddr = addr->sin_addr.s_addr;
374#if IS_ENABLED(CONFIG_IPV6)
375 } else if (saddr->sa_family == AF_INET6) {
376 struct sockaddr_in6 *addr = (struct sockaddr_in6 *) saddr;
377 struct ipv6_pinfo *np = inet6_sk(sk);
378 sk->sk_v6_rcv_saddr = np->saddr = addr->sin6_addr;
379#endif
380 }
381}
382
383static void ping_clear_saddr(struct sock *sk, int dif)
384{
385 sk->sk_bound_dev_if = dif;
386 if (sk->sk_family == AF_INET) {
387 struct inet_sock *isk = inet_sk(sk);
388 isk->inet_rcv_saddr = isk->inet_saddr = 0;
389#if IS_ENABLED(CONFIG_IPV6)
390 } else if (sk->sk_family == AF_INET6) {
391 struct ipv6_pinfo *np = inet6_sk(sk);
392 memset(&sk->sk_v6_rcv_saddr, 0, sizeof(sk->sk_v6_rcv_saddr));
393 memset(&np->saddr, 0, sizeof(np->saddr));
394#endif
395 }
396}
397/*
398 * We need our own bind because there are no privileged id's == local ports.
399 * Moreover, we don't allow binding to multi- and broadcast addresses.
400 */
401
402int ping_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len)
403{
404 struct inet_sock *isk = inet_sk(sk);
405 unsigned short snum;
406 int err;
407 int dif = sk->sk_bound_dev_if;
408
409 err = ping_check_bind_addr(sk, isk, uaddr, addr_len);
410 if (err)
411 return err;
412
413 lock_sock(sk);
414
415 err = -EINVAL;
416 if (isk->inet_num != 0)
417 goto out;
418
419 err = -EADDRINUSE;
420 ping_set_saddr(sk, uaddr);
421 snum = ntohs(((struct sockaddr_in *)uaddr)->sin_port);
422 if (ping_get_port(sk, snum) != 0) {
423 ping_clear_saddr(sk, dif);
424 goto out;
425 }
426
427 pr_debug("after bind(): num = %d, dif = %d\n",
428 (int)isk->inet_num,
429 (int)sk->sk_bound_dev_if);
430
431 err = 0;
432 if (sk->sk_family == AF_INET && isk->inet_rcv_saddr)
433 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
434#if IS_ENABLED(CONFIG_IPV6)
435 if (sk->sk_family == AF_INET6 && !ipv6_addr_any(&sk->sk_v6_rcv_saddr))
436 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
437#endif
438
439 if (snum)
440 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
441 isk->inet_sport = htons(isk->inet_num);
442 isk->inet_daddr = 0;
443 isk->inet_dport = 0;
444
445#if IS_ENABLED(CONFIG_IPV6)
446 if (sk->sk_family == AF_INET6)
447 memset(&sk->sk_v6_daddr, 0, sizeof(sk->sk_v6_daddr));
448#endif
449
450 sk_dst_reset(sk);
451out:
452 release_sock(sk);
453 pr_debug("ping_v4_bind -> %d\n", err);
454 return err;
455}
456EXPORT_SYMBOL_GPL(ping_bind);
457
458/*
459 * Is this a supported type of ICMP message?
460 */
461
462static inline int ping_supported(int family, int type, int code)
463{
464 return (family == AF_INET && type == ICMP_ECHO && code == 0) ||
465 (family == AF_INET6 && type == ICMPV6_ECHO_REQUEST && code == 0);
466}
467
468/*
469 * This routine is called by the ICMP module when it gets some
470 * sort of error condition.
471 */
472
473void ping_err(struct sk_buff *skb, int offset, u32 info)
474{
475 int family;
476 struct icmphdr *icmph;
477 struct inet_sock *inet_sock;
478 int type;
479 int code;
480 struct net *net = dev_net(skb->dev);
481 struct sock *sk;
482 int harderr;
483 int err;
484
485 if (skb->protocol == htons(ETH_P_IP)) {
486 family = AF_INET;
487 type = icmp_hdr(skb)->type;
488 code = icmp_hdr(skb)->code;
489 icmph = (struct icmphdr *)(skb->data + offset);
490 } else if (skb->protocol == htons(ETH_P_IPV6)) {
491 family = AF_INET6;
492 type = icmp6_hdr(skb)->icmp6_type;
493 code = icmp6_hdr(skb)->icmp6_code;
494 icmph = (struct icmphdr *) (skb->data + offset);
495 } else {
496 BUG();
497 }
498
499 /* We assume the packet has already been checked by icmp_unreach */
500
501 if (!ping_supported(family, icmph->type, icmph->code))
502 return;
503
504 pr_debug("ping_err(proto=0x%x,type=%d,code=%d,id=%04x,seq=%04x)\n",
505 skb->protocol, type, code, ntohs(icmph->un.echo.id),
506 ntohs(icmph->un.echo.sequence));
507
508 sk = ping_lookup(net, skb, ntohs(icmph->un.echo.id));
509 if (sk == NULL) {
510 pr_debug("no socket, dropping\n");
511 return; /* No socket for error */
512 }
513 pr_debug("err on socket %p\n", sk);
514
515 err = 0;
516 harderr = 0;
517 inet_sock = inet_sk(sk);
518
519 if (skb->protocol == htons(ETH_P_IP)) {
520 switch (type) {
521 default:
522 case ICMP_TIME_EXCEEDED:
523 err = EHOSTUNREACH;
524 break;
525 case ICMP_SOURCE_QUENCH:
526 /* This is not a real error but ping wants to see it.
527 * Report it with some fake errno.
528 */
529 err = EREMOTEIO;
530 break;
531 case ICMP_PARAMETERPROB:
532 err = EPROTO;
533 harderr = 1;
534 break;
535 case ICMP_DEST_UNREACH:
536 if (code == ICMP_FRAG_NEEDED) { /* Path MTU discovery */
537 ipv4_sk_update_pmtu(skb, sk, info);
538 if (inet_sock->pmtudisc != IP_PMTUDISC_DONT) {
539 err = EMSGSIZE;
540 harderr = 1;
541 break;
542 }
543 goto out;
544 }
545 err = EHOSTUNREACH;
546 if (code <= NR_ICMP_UNREACH) {
547 harderr = icmp_err_convert[code].fatal;
548 err = icmp_err_convert[code].errno;
549 }
550 break;
551 case ICMP_REDIRECT:
552 /* See ICMP_SOURCE_QUENCH */
553 ipv4_sk_redirect(skb, sk);
554 err = EREMOTEIO;
555 break;
556 }
557#if IS_ENABLED(CONFIG_IPV6)
558 } else if (skb->protocol == htons(ETH_P_IPV6)) {
559 harderr = pingv6_ops.icmpv6_err_convert(type, code, &err);
560#endif
561 }
562
563 /*
564 * RFC1122: OK. Passes ICMP errors back to application, as per
565 * 4.1.3.3.
566 */
567 if ((family == AF_INET && !inet_sock->recverr) ||
568 (family == AF_INET6 && !inet6_sk(sk)->recverr)) {
569 if (!harderr || sk->sk_state != TCP_ESTABLISHED)
570 goto out;
571 } else {
572 if (family == AF_INET) {
573 ip_icmp_error(sk, skb, err, 0 /* no remote port */,
574 info, (u8 *)icmph);
575#if IS_ENABLED(CONFIG_IPV6)
576 } else if (family == AF_INET6) {
577 pingv6_ops.ipv6_icmp_error(sk, skb, err, 0,
578 info, (u8 *)icmph);
579#endif
580 }
581 }
582 sk->sk_err = err;
583 sk->sk_error_report(sk);
584out:
585 sock_put(sk);
586}
587EXPORT_SYMBOL_GPL(ping_err);
588
589/*
590 * Copy and checksum an ICMP Echo packet from user space into a buffer
591 * starting from the payload.
592 */
593
594int ping_getfrag(void *from, char *to,
595 int offset, int fraglen, int odd, struct sk_buff *skb)
596{
597 struct pingfakehdr *pfh = (struct pingfakehdr *)from;
598
599 if (offset == 0) {
600 if (fraglen < sizeof(struct icmphdr))
601 BUG();
602 if (csum_partial_copy_fromiovecend(to + sizeof(struct icmphdr),
603 pfh->iov, 0, fraglen - sizeof(struct icmphdr),
604 &pfh->wcheck))
605 return -EFAULT;
606 } else if (offset < sizeof(struct icmphdr)) {
607 BUG();
608 } else {
609 if (csum_partial_copy_fromiovecend
610 (to, pfh->iov, offset - sizeof(struct icmphdr),
611 fraglen, &pfh->wcheck))
612 return -EFAULT;
613 }
614
615#if IS_ENABLED(CONFIG_IPV6)
616 /* For IPv6, checksum each skb as we go along, as expected by
617 * icmpv6_push_pending_frames. For IPv4, accumulate the checksum in
618 * wcheck, it will be finalized in ping_v4_push_pending_frames.
619 */
620 if (pfh->family == AF_INET6) {
621 skb->csum = pfh->wcheck;
622 skb->ip_summed = CHECKSUM_NONE;
623 pfh->wcheck = 0;
624 }
625#endif
626
627 return 0;
628}
629EXPORT_SYMBOL_GPL(ping_getfrag);
630
631static int ping_v4_push_pending_frames(struct sock *sk, struct pingfakehdr *pfh,
632 struct flowi4 *fl4)
633{
634 struct sk_buff *skb = skb_peek(&sk->sk_write_queue);
635
636 pfh->wcheck = csum_partial((char *)&pfh->icmph,
637 sizeof(struct icmphdr), pfh->wcheck);
638 pfh->icmph.checksum = csum_fold(pfh->wcheck);
639 memcpy(icmp_hdr(skb), &pfh->icmph, sizeof(struct icmphdr));
640 skb->ip_summed = CHECKSUM_NONE;
641 return ip_push_pending_frames(sk, fl4);
642}
643
644int ping_common_sendmsg(int family, struct msghdr *msg, size_t len,
645 void *user_icmph, size_t icmph_len) {
646 u8 type, code;
647
648 if (len > 0xFFFF)
649 return -EMSGSIZE;
650
651 /*
652 * Check the flags.
653 */
654
655 /* Mirror BSD error message compatibility */
656 if (msg->msg_flags & MSG_OOB)
657 return -EOPNOTSUPP;
658
659 /*
660 * Fetch the ICMP header provided by the userland.
661 * iovec is modified! The ICMP header is consumed.
662 */
663 if (memcpy_fromiovec(user_icmph, msg->msg_iov, icmph_len))
664 return -EFAULT;
665
666 if (family == AF_INET) {
667 type = ((struct icmphdr *) user_icmph)->type;
668 code = ((struct icmphdr *) user_icmph)->code;
669#if IS_ENABLED(CONFIG_IPV6)
670 } else if (family == AF_INET6) {
671 type = ((struct icmp6hdr *) user_icmph)->icmp6_type;
672 code = ((struct icmp6hdr *) user_icmph)->icmp6_code;
673#endif
674 } else {
675 BUG();
676 }
677
678 if (!ping_supported(family, type, code))
679 return -EINVAL;
680
681 return 0;
682}
683EXPORT_SYMBOL_GPL(ping_common_sendmsg);
684
685static int ping_v4_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
686 size_t len)
687{
688 struct net *net = sock_net(sk);
689 struct flowi4 fl4;
690 struct inet_sock *inet = inet_sk(sk);
691 struct ipcm_cookie ipc;
692 struct icmphdr user_icmph;
693 struct pingfakehdr pfh;
694 struct rtable *rt = NULL;
695 struct ip_options_data opt_copy;
696 int free = 0;
697 __be32 saddr, daddr, faddr;
698 u8 tos;
699 int err;
700
701 pr_debug("ping_v4_sendmsg(sk=%p,sk->num=%u)\n", inet, inet->inet_num);
702
703 err = ping_common_sendmsg(AF_INET, msg, len, &user_icmph,
704 sizeof(user_icmph));
705 if (err)
706 return err;
707
708 /*
709 * Get and verify the address.
710 */
711
712 if (msg->msg_name) {
713 DECLARE_SOCKADDR(struct sockaddr_in *, usin, msg->msg_name);
714 if (msg->msg_namelen < sizeof(*usin))
715 return -EINVAL;
716 if (usin->sin_family != AF_INET)
717 return -EINVAL;
718 daddr = usin->sin_addr.s_addr;
719 /* no remote port */
720 } else {
721 if (sk->sk_state != TCP_ESTABLISHED)
722 return -EDESTADDRREQ;
723 daddr = inet->inet_daddr;
724 /* no remote port */
725 }
726
727 ipc.addr = inet->inet_saddr;
728 ipc.opt = NULL;
729 ipc.oif = sk->sk_bound_dev_if;
730 ipc.tx_flags = 0;
731 ipc.ttl = 0;
732 ipc.tos = -1;
733
734 sock_tx_timestamp(sk, &ipc.tx_flags);
735
736 if (msg->msg_controllen) {
737 err = ip_cmsg_send(sock_net(sk), msg, &ipc, false);
738 if (err)
739 return err;
740 if (ipc.opt)
741 free = 1;
742 }
743 if (!ipc.opt) {
744 struct ip_options_rcu *inet_opt;
745
746 rcu_read_lock();
747 inet_opt = rcu_dereference(inet->inet_opt);
748 if (inet_opt) {
749 memcpy(&opt_copy, inet_opt,
750 sizeof(*inet_opt) + inet_opt->opt.optlen);
751 ipc.opt = &opt_copy.opt;
752 }
753 rcu_read_unlock();
754 }
755
756 saddr = ipc.addr;
757 ipc.addr = faddr = daddr;
758
759 if (ipc.opt && ipc.opt->opt.srr) {
760 if (!daddr)
761 return -EINVAL;
762 faddr = ipc.opt->opt.faddr;
763 }
764 tos = get_rttos(&ipc, inet);
765 if (sock_flag(sk, SOCK_LOCALROUTE) ||
766 (msg->msg_flags & MSG_DONTROUTE) ||
767 (ipc.opt && ipc.opt->opt.is_strictroute)) {
768 tos |= RTO_ONLINK;
769 }
770
771 if (ipv4_is_multicast(daddr)) {
772 if (!ipc.oif)
773 ipc.oif = inet->mc_index;
774 if (!saddr)
775 saddr = inet->mc_addr;
776 } else if (!ipc.oif)
777 ipc.oif = inet->uc_index;
778
779 flowi4_init_output(&fl4, ipc.oif, sk->sk_mark, tos,
780 RT_SCOPE_UNIVERSE, sk->sk_protocol,
781 inet_sk_flowi_flags(sk), faddr, saddr, 0, 0);
782
783 security_sk_classify_flow(sk, flowi4_to_flowi(&fl4));
784 rt = ip_route_output_flow(net, &fl4, sk);
785 if (IS_ERR(rt)) {
786 err = PTR_ERR(rt);
787 rt = NULL;
788 if (err == -ENETUNREACH)
789 IP_INC_STATS(net, IPSTATS_MIB_OUTNOROUTES);
790 goto out;
791 }
792
793 err = -EACCES;
794 if ((rt->rt_flags & RTCF_BROADCAST) &&
795 !sock_flag(sk, SOCK_BROADCAST))
796 goto out;
797
798 if (msg->msg_flags & MSG_CONFIRM)
799 goto do_confirm;
800back_from_confirm:
801
802 if (!ipc.addr)
803 ipc.addr = fl4.daddr;
804
805 lock_sock(sk);
806
807 pfh.icmph.type = user_icmph.type; /* already checked */
808 pfh.icmph.code = user_icmph.code; /* ditto */
809 pfh.icmph.checksum = 0;
810 pfh.icmph.un.echo.id = inet->inet_sport;
811 pfh.icmph.un.echo.sequence = user_icmph.un.echo.sequence;
812 pfh.iov = msg->msg_iov;
813 pfh.wcheck = 0;
814 pfh.family = AF_INET;
815
816 err = ip_append_data(sk, &fl4, ping_getfrag, &pfh, len,
817 0, &ipc, &rt, msg->msg_flags);
818 if (err)
819 ip_flush_pending_frames(sk);
820 else
821 err = ping_v4_push_pending_frames(sk, &pfh, &fl4);
822 release_sock(sk);
823
824out:
825 ip_rt_put(rt);
826 if (free)
827 kfree(ipc.opt);
828 if (!err) {
829 icmp_out_count(sock_net(sk), user_icmph.type);
830 return len;
831 }
832 return err;
833
834do_confirm:
835 dst_confirm(&rt->dst);
836 if (!(msg->msg_flags & MSG_PROBE) || len)
837 goto back_from_confirm;
838 err = 0;
839 goto out;
840}
841
842int ping_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
843 size_t len, int noblock, int flags, int *addr_len)
844{
845 struct inet_sock *isk = inet_sk(sk);
846 int family = sk->sk_family;
847 struct sk_buff *skb;
848 int copied, err;
849
850 pr_debug("ping_recvmsg(sk=%p,sk->num=%u)\n", isk, isk->inet_num);
851
852 err = -EOPNOTSUPP;
853 if (flags & MSG_OOB)
854 goto out;
855
856 if (flags & MSG_ERRQUEUE) {
857 if (family == AF_INET) {
858 return ip_recv_error(sk, msg, len, addr_len);
859#if IS_ENABLED(CONFIG_IPV6)
860 } else if (family == AF_INET6) {
861 return pingv6_ops.ipv6_recv_error(sk, msg, len,
862 addr_len);
863#endif
864 }
865 }
866
867 skb = skb_recv_datagram(sk, flags, noblock, &err);
868 if (!skb)
869 goto out;
870
871 copied = skb->len;
872 if (copied > len) {
873 msg->msg_flags |= MSG_TRUNC;
874 copied = len;
875 }
876
877 /* Don't bother checking the checksum */
878 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
879 if (err)
880 goto done;
881
882 sock_recv_timestamp(msg, sk, skb);
883
884 /* Copy the address and add cmsg data. */
885 if (family == AF_INET) {
886 DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name);
887
888 if (sin) {
889 sin->sin_family = AF_INET;
890 sin->sin_port = 0 /* skb->h.uh->source */;
891 sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
892 memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
893 *addr_len = sizeof(*sin);
894 }
895
896 if (isk->cmsg_flags)
897 ip_cmsg_recv(msg, skb);
898
899#if IS_ENABLED(CONFIG_IPV6)
900 } else if (family == AF_INET6) {
901 struct ipv6_pinfo *np = inet6_sk(sk);
902 struct ipv6hdr *ip6 = ipv6_hdr(skb);
903 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
904
905 if (sin6) {
906 sin6->sin6_family = AF_INET6;
907 sin6->sin6_port = 0;
908 sin6->sin6_addr = ip6->saddr;
909 sin6->sin6_flowinfo = 0;
910 if (np->sndflow)
911 sin6->sin6_flowinfo = ip6_flowinfo(ip6);
912 sin6->sin6_scope_id =
913 ipv6_iface_scope_id(&sin6->sin6_addr,
914 IP6CB(skb)->iif);
915 *addr_len = sizeof(*sin6);
916 }
917
918 if (inet6_sk(sk)->rxopt.all)
919 pingv6_ops.ip6_datagram_recv_common_ctl(sk, msg, skb);
920 if (skb->protocol == htons(ETH_P_IPV6) &&
921 inet6_sk(sk)->rxopt.all)
922 pingv6_ops.ip6_datagram_recv_specific_ctl(sk, msg, skb);
923 else if (skb->protocol == htons(ETH_P_IP) && isk->cmsg_flags)
924 ip_cmsg_recv(msg, skb);
925#endif
926 } else {
927 BUG();
928 }
929
930 err = copied;
931
932done:
933 skb_free_datagram(sk, skb);
934out:
935 pr_debug("ping_recvmsg -> %d\n", err);
936 return err;
937}
938EXPORT_SYMBOL_GPL(ping_recvmsg);
939
940int ping_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
941{
942 pr_debug("ping_queue_rcv_skb(sk=%p,sk->num=%d,skb=%p)\n",
943 inet_sk(sk), inet_sk(sk)->inet_num, skb);
944 if (sock_queue_rcv_skb(sk, skb) < 0) {
945 kfree_skb(skb);
946 pr_debug("ping_queue_rcv_skb -> failed\n");
947 return -1;
948 }
949 return 0;
950}
951EXPORT_SYMBOL_GPL(ping_queue_rcv_skb);
952
953
954/*
955 * All we need to do is get the socket.
956 */
957
958void ping_rcv(struct sk_buff *skb)
959{
960 struct sock *sk;
961 struct net *net = dev_net(skb->dev);
962 struct icmphdr *icmph = icmp_hdr(skb);
963
964 /* We assume the packet has already been checked by icmp_rcv */
965
966 pr_debug("ping_rcv(skb=%p,id=%04x,seq=%04x)\n",
967 skb, ntohs(icmph->un.echo.id), ntohs(icmph->un.echo.sequence));
968
969 /* Push ICMP header back */
970 skb_push(skb, skb->data - (u8 *)icmph);
971
972 sk = ping_lookup(net, skb, ntohs(icmph->un.echo.id));
973 if (sk != NULL) {
974 pr_debug("rcv on socket %p\n", sk);
975 ping_queue_rcv_skb(sk, skb_get(skb));
976 sock_put(sk);
977 return;
978 }
979 pr_debug("no socket, dropping\n");
980
981 /* We're called from icmp_rcv(). kfree_skb() is done there. */
982}
983EXPORT_SYMBOL_GPL(ping_rcv);
984
985struct proto ping_prot = {
986 .name = "PING",
987 .owner = THIS_MODULE,
988 .init = ping_init_sock,
989 .close = ping_close,
990 .connect = ip4_datagram_connect,
991 .disconnect = udp_disconnect,
992 .setsockopt = ip_setsockopt,
993 .getsockopt = ip_getsockopt,
994 .sendmsg = ping_v4_sendmsg,
995 .recvmsg = ping_recvmsg,
996 .bind = ping_bind,
997 .backlog_rcv = ping_queue_rcv_skb,
998 .release_cb = ip4_datagram_release_cb,
999 .hash = ping_hash,
1000 .unhash = ping_unhash,
1001 .get_port = ping_get_port,
1002 .obj_size = sizeof(struct inet_sock),
1003};
1004EXPORT_SYMBOL(ping_prot);
1005
1006#ifdef CONFIG_PROC_FS
1007
1008static struct sock *ping_get_first(struct seq_file *seq, int start)
1009{
1010 struct sock *sk;
1011 struct ping_iter_state *state = seq->private;
1012 struct net *net = seq_file_net(seq);
1013
1014 for (state->bucket = start; state->bucket < PING_HTABLE_SIZE;
1015 ++state->bucket) {
1016 struct hlist_nulls_node *node;
1017 struct hlist_nulls_head *hslot;
1018
1019 hslot = &ping_table.hash[state->bucket];
1020
1021 if (hlist_nulls_empty(hslot))
1022 continue;
1023
1024 sk_nulls_for_each(sk, node, hslot) {
1025 if (net_eq(sock_net(sk), net) &&
1026 sk->sk_family == state->family)
1027 goto found;
1028 }
1029 }
1030 sk = NULL;
1031found:
1032 return sk;
1033}
1034
1035static struct sock *ping_get_next(struct seq_file *seq, struct sock *sk)
1036{
1037 struct ping_iter_state *state = seq->private;
1038 struct net *net = seq_file_net(seq);
1039
1040 do {
1041 sk = sk_nulls_next(sk);
1042 } while (sk && (!net_eq(sock_net(sk), net)));
1043
1044 if (!sk)
1045 return ping_get_first(seq, state->bucket + 1);
1046 return sk;
1047}
1048
1049static struct sock *ping_get_idx(struct seq_file *seq, loff_t pos)
1050{
1051 struct sock *sk = ping_get_first(seq, 0);
1052
1053 if (sk)
1054 while (pos && (sk = ping_get_next(seq, sk)) != NULL)
1055 --pos;
1056 return pos ? NULL : sk;
1057}
1058
1059void *ping_seq_start(struct seq_file *seq, loff_t *pos, sa_family_t family)
1060{
1061 struct ping_iter_state *state = seq->private;
1062 state->bucket = 0;
1063 state->family = family;
1064
1065 read_lock_bh(&ping_table.lock);
1066
1067 return *pos ? ping_get_idx(seq, *pos-1) : SEQ_START_TOKEN;
1068}
1069EXPORT_SYMBOL_GPL(ping_seq_start);
1070
1071static void *ping_v4_seq_start(struct seq_file *seq, loff_t *pos)
1072{
1073 return ping_seq_start(seq, pos, AF_INET);
1074}
1075
1076void *ping_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1077{
1078 struct sock *sk;
1079
1080 if (v == SEQ_START_TOKEN)
1081 sk = ping_get_idx(seq, 0);
1082 else
1083 sk = ping_get_next(seq, v);
1084
1085 ++*pos;
1086 return sk;
1087}
1088EXPORT_SYMBOL_GPL(ping_seq_next);
1089
1090void ping_seq_stop(struct seq_file *seq, void *v)
1091{
1092 read_unlock_bh(&ping_table.lock);
1093}
1094EXPORT_SYMBOL_GPL(ping_seq_stop);
1095
1096static void ping_v4_format_sock(struct sock *sp, struct seq_file *f,
1097 int bucket)
1098{
1099 struct inet_sock *inet = inet_sk(sp);
1100 __be32 dest = inet->inet_daddr;
1101 __be32 src = inet->inet_rcv_saddr;
1102 __u16 destp = ntohs(inet->inet_dport);
1103 __u16 srcp = ntohs(inet->inet_sport);
1104
1105 seq_printf(f, "%5d: %08X:%04X %08X:%04X"
1106 " %02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %d",
1107 bucket, src, srcp, dest, destp, sp->sk_state,
1108 sk_wmem_alloc_get(sp),
1109 sk_rmem_alloc_get(sp),
1110 0, 0L, 0,
1111 from_kuid_munged(seq_user_ns(f), sock_i_uid(sp)),
1112 0, sock_i_ino(sp),
1113 atomic_read(&sp->sk_refcnt), sp,
1114 atomic_read(&sp->sk_drops));
1115}
1116
1117static int ping_v4_seq_show(struct seq_file *seq, void *v)
1118{
1119 seq_setwidth(seq, 127);
1120 if (v == SEQ_START_TOKEN)
1121 seq_puts(seq, " sl local_address rem_address st tx_queue "
1122 "rx_queue tr tm->when retrnsmt uid timeout "
1123 "inode ref pointer drops");
1124 else {
1125 struct ping_iter_state *state = seq->private;
1126
1127 ping_v4_format_sock(v, seq, state->bucket);
1128 }
1129 seq_pad(seq, '\n');
1130 return 0;
1131}
1132
1133static const struct seq_operations ping_v4_seq_ops = {
1134 .show = ping_v4_seq_show,
1135 .start = ping_v4_seq_start,
1136 .next = ping_seq_next,
1137 .stop = ping_seq_stop,
1138};
1139
1140static int ping_seq_open(struct inode *inode, struct file *file)
1141{
1142 struct ping_seq_afinfo *afinfo = PDE_DATA(inode);
1143 return seq_open_net(inode, file, &afinfo->seq_ops,
1144 sizeof(struct ping_iter_state));
1145}
1146
1147const struct file_operations ping_seq_fops = {
1148 .open = ping_seq_open,
1149 .read = seq_read,
1150 .llseek = seq_lseek,
1151 .release = seq_release_net,
1152};
1153EXPORT_SYMBOL_GPL(ping_seq_fops);
1154
1155static struct ping_seq_afinfo ping_v4_seq_afinfo = {
1156 .name = "icmp",
1157 .family = AF_INET,
1158 .seq_fops = &ping_seq_fops,
1159 .seq_ops = {
1160 .start = ping_v4_seq_start,
1161 .show = ping_v4_seq_show,
1162 .next = ping_seq_next,
1163 .stop = ping_seq_stop,
1164 },
1165};
1166
1167int ping_proc_register(struct net *net, struct ping_seq_afinfo *afinfo)
1168{
1169 struct proc_dir_entry *p;
1170 p = proc_create_data(afinfo->name, S_IRUGO, net->proc_net,
1171 afinfo->seq_fops, afinfo);
1172 if (!p)
1173 return -ENOMEM;
1174 return 0;
1175}
1176EXPORT_SYMBOL_GPL(ping_proc_register);
1177
1178void ping_proc_unregister(struct net *net, struct ping_seq_afinfo *afinfo)
1179{
1180 remove_proc_entry(afinfo->name, net->proc_net);
1181}
1182EXPORT_SYMBOL_GPL(ping_proc_unregister);
1183
1184static int __net_init ping_v4_proc_init_net(struct net *net)
1185{
1186 return ping_proc_register(net, &ping_v4_seq_afinfo);
1187}
1188
1189static void __net_exit ping_v4_proc_exit_net(struct net *net)
1190{
1191 ping_proc_unregister(net, &ping_v4_seq_afinfo);
1192}
1193
1194static struct pernet_operations ping_v4_net_ops = {
1195 .init = ping_v4_proc_init_net,
1196 .exit = ping_v4_proc_exit_net,
1197};
1198
1199int __init ping_proc_init(void)
1200{
1201 return register_pernet_subsys(&ping_v4_net_ops);
1202}
1203
1204void ping_proc_exit(void)
1205{
1206 unregister_pernet_subsys(&ping_v4_net_ops);
1207}
1208
1209#endif
1210
1211void __init ping_init(void)
1212{
1213 int i;
1214
1215 for (i = 0; i < PING_HTABLE_SIZE; i++)
1216 INIT_HLIST_NULLS_HEAD(&ping_table.hash[i], i);
1217 rwlock_init(&ping_table.lock);
1218}
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}