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Merge remote-tracking branches 'asoc/fix/rt5665', 'asoc/fix/simple', 'asoc/fix/sti...
[mirror_ubuntu-focal-kernel.git] / net / ipv4 / ping.c
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
56 struct ping_table {
57 struct hlist_nulls_head hash[PING_HTABLE_SIZE];
58 rwlock_t lock;
59 };
60
61 static struct ping_table ping_table;
62 struct pingv6_ops pingv6_ops;
63 EXPORT_SYMBOL_GPL(pingv6_ops);
64
65 static u16 ping_port_rover;
66
67 static 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 }
74 EXPORT_SYMBOL_GPL(ping_hash);
75
76 static 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
82 int 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;
110 next_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
142 fail:
143 write_unlock_bh(&ping_table.lock);
144 return 1;
145 }
146 EXPORT_SYMBOL_GPL(ping_get_port);
147
148 int 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
156 void 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 }
171 EXPORT_SYMBOL_GPL(ping_unhash);
172
173 static 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;
235 exit:
236 read_unlock_bh(&ping_table.lock);
237
238 return sk;
239 }
240
241 static 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
256 int 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
282 out_release_group:
283 put_group_info(group_info);
284 return ret;
285 }
286 EXPORT_SYMBOL_GPL(ping_init_sock);
287
288 void 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 }
296 EXPORT_SYMBOL_GPL(ping_close);
297
298 /* Checks the bind address and possibly modifies sk->sk_bound_dev_if. */
299 static 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
377 static 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
392 static 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
411 int 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 = %hu, dif = %d\n",
437 isk->inet_num,
438 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);
460 out:
461 release_sock(sk);
462 pr_debug("ping_v4_bind -> %d\n", err);
463 return err;
464 }
465 EXPORT_SYMBOL_GPL(ping_bind);
466
467 /*
468 * Is this a supported type of ICMP message?
469 */
470
471 static 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
482 void 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);
593 out:
594 sock_put(sk);
595 }
596 EXPORT_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
603 int 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 }
638 EXPORT_SYMBOL_GPL(ping_getfrag);
639
640 static 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
655 int 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 }
698 EXPORT_SYMBOL_GPL(ping_common_sendmsg);
699
700 static 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;
818 back_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
842 out:
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
852 do_confirm:
853 if (msg->msg_flags & MSG_PROBE)
854 dst_confirm_neigh(&rt->dst, &fl4.daddr);
855 if (!(msg->msg_flags & MSG_PROBE) || len)
856 goto back_from_confirm;
857 err = 0;
858 goto out;
859 }
860
861 int ping_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int noblock,
862 int flags, int *addr_len)
863 {
864 struct inet_sock *isk = inet_sk(sk);
865 int family = sk->sk_family;
866 struct sk_buff *skb;
867 int copied, err;
868
869 pr_debug("ping_recvmsg(sk=%p,sk->num=%u)\n", isk, isk->inet_num);
870
871 err = -EOPNOTSUPP;
872 if (flags & MSG_OOB)
873 goto out;
874
875 if (flags & MSG_ERRQUEUE)
876 return inet_recv_error(sk, msg, len, addr_len);
877
878 skb = skb_recv_datagram(sk, flags, noblock, &err);
879 if (!skb)
880 goto out;
881
882 copied = skb->len;
883 if (copied > len) {
884 msg->msg_flags |= MSG_TRUNC;
885 copied = len;
886 }
887
888 /* Don't bother checking the checksum */
889 err = skb_copy_datagram_msg(skb, 0, msg, copied);
890 if (err)
891 goto done;
892
893 sock_recv_timestamp(msg, sk, skb);
894
895 /* Copy the address and add cmsg data. */
896 if (family == AF_INET) {
897 DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name);
898
899 if (sin) {
900 sin->sin_family = AF_INET;
901 sin->sin_port = 0 /* skb->h.uh->source */;
902 sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
903 memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
904 *addr_len = sizeof(*sin);
905 }
906
907 if (isk->cmsg_flags)
908 ip_cmsg_recv(msg, skb);
909
910 #if IS_ENABLED(CONFIG_IPV6)
911 } else if (family == AF_INET6) {
912 struct ipv6_pinfo *np = inet6_sk(sk);
913 struct ipv6hdr *ip6 = ipv6_hdr(skb);
914 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
915
916 if (sin6) {
917 sin6->sin6_family = AF_INET6;
918 sin6->sin6_port = 0;
919 sin6->sin6_addr = ip6->saddr;
920 sin6->sin6_flowinfo = 0;
921 if (np->sndflow)
922 sin6->sin6_flowinfo = ip6_flowinfo(ip6);
923 sin6->sin6_scope_id =
924 ipv6_iface_scope_id(&sin6->sin6_addr,
925 inet6_iif(skb));
926 *addr_len = sizeof(*sin6);
927 }
928
929 if (inet6_sk(sk)->rxopt.all)
930 pingv6_ops.ip6_datagram_recv_common_ctl(sk, msg, skb);
931 if (skb->protocol == htons(ETH_P_IPV6) &&
932 inet6_sk(sk)->rxopt.all)
933 pingv6_ops.ip6_datagram_recv_specific_ctl(sk, msg, skb);
934 else if (skb->protocol == htons(ETH_P_IP) && isk->cmsg_flags)
935 ip_cmsg_recv(msg, skb);
936 #endif
937 } else {
938 BUG();
939 }
940
941 err = copied;
942
943 done:
944 skb_free_datagram(sk, skb);
945 out:
946 pr_debug("ping_recvmsg -> %d\n", err);
947 return err;
948 }
949 EXPORT_SYMBOL_GPL(ping_recvmsg);
950
951 int ping_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
952 {
953 pr_debug("ping_queue_rcv_skb(sk=%p,sk->num=%d,skb=%p)\n",
954 inet_sk(sk), inet_sk(sk)->inet_num, skb);
955 if (sock_queue_rcv_skb(sk, skb) < 0) {
956 kfree_skb(skb);
957 pr_debug("ping_queue_rcv_skb -> failed\n");
958 return -1;
959 }
960 return 0;
961 }
962 EXPORT_SYMBOL_GPL(ping_queue_rcv_skb);
963
964
965 /*
966 * All we need to do is get the socket.
967 */
968
969 bool ping_rcv(struct sk_buff *skb)
970 {
971 struct sock *sk;
972 struct net *net = dev_net(skb->dev);
973 struct icmphdr *icmph = icmp_hdr(skb);
974
975 /* We assume the packet has already been checked by icmp_rcv */
976
977 pr_debug("ping_rcv(skb=%p,id=%04x,seq=%04x)\n",
978 skb, ntohs(icmph->un.echo.id), ntohs(icmph->un.echo.sequence));
979
980 /* Push ICMP header back */
981 skb_push(skb, skb->data - (u8 *)icmph);
982
983 sk = ping_lookup(net, skb, ntohs(icmph->un.echo.id));
984 if (sk) {
985 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
986
987 pr_debug("rcv on socket %p\n", sk);
988 if (skb2)
989 ping_queue_rcv_skb(sk, skb2);
990 sock_put(sk);
991 return true;
992 }
993 pr_debug("no socket, dropping\n");
994
995 return false;
996 }
997 EXPORT_SYMBOL_GPL(ping_rcv);
998
999 struct proto ping_prot = {
1000 .name = "PING",
1001 .owner = THIS_MODULE,
1002 .init = ping_init_sock,
1003 .close = ping_close,
1004 .connect = ip4_datagram_connect,
1005 .disconnect = __udp_disconnect,
1006 .setsockopt = ip_setsockopt,
1007 .getsockopt = ip_getsockopt,
1008 .sendmsg = ping_v4_sendmsg,
1009 .recvmsg = ping_recvmsg,
1010 .bind = ping_bind,
1011 .backlog_rcv = ping_queue_rcv_skb,
1012 .release_cb = ip4_datagram_release_cb,
1013 .hash = ping_hash,
1014 .unhash = ping_unhash,
1015 .get_port = ping_get_port,
1016 .obj_size = sizeof(struct inet_sock),
1017 };
1018 EXPORT_SYMBOL(ping_prot);
1019
1020 #ifdef CONFIG_PROC_FS
1021
1022 static struct sock *ping_get_first(struct seq_file *seq, int start)
1023 {
1024 struct sock *sk;
1025 struct ping_iter_state *state = seq->private;
1026 struct net *net = seq_file_net(seq);
1027
1028 for (state->bucket = start; state->bucket < PING_HTABLE_SIZE;
1029 ++state->bucket) {
1030 struct hlist_nulls_node *node;
1031 struct hlist_nulls_head *hslot;
1032
1033 hslot = &ping_table.hash[state->bucket];
1034
1035 if (hlist_nulls_empty(hslot))
1036 continue;
1037
1038 sk_nulls_for_each(sk, node, hslot) {
1039 if (net_eq(sock_net(sk), net) &&
1040 sk->sk_family == state->family)
1041 goto found;
1042 }
1043 }
1044 sk = NULL;
1045 found:
1046 return sk;
1047 }
1048
1049 static struct sock *ping_get_next(struct seq_file *seq, struct sock *sk)
1050 {
1051 struct ping_iter_state *state = seq->private;
1052 struct net *net = seq_file_net(seq);
1053
1054 do {
1055 sk = sk_nulls_next(sk);
1056 } while (sk && (!net_eq(sock_net(sk), net)));
1057
1058 if (!sk)
1059 return ping_get_first(seq, state->bucket + 1);
1060 return sk;
1061 }
1062
1063 static struct sock *ping_get_idx(struct seq_file *seq, loff_t pos)
1064 {
1065 struct sock *sk = ping_get_first(seq, 0);
1066
1067 if (sk)
1068 while (pos && (sk = ping_get_next(seq, sk)) != NULL)
1069 --pos;
1070 return pos ? NULL : sk;
1071 }
1072
1073 void *ping_seq_start(struct seq_file *seq, loff_t *pos, sa_family_t family)
1074 __acquires(ping_table.lock)
1075 {
1076 struct ping_iter_state *state = seq->private;
1077 state->bucket = 0;
1078 state->family = family;
1079
1080 read_lock_bh(&ping_table.lock);
1081
1082 return *pos ? ping_get_idx(seq, *pos-1) : SEQ_START_TOKEN;
1083 }
1084 EXPORT_SYMBOL_GPL(ping_seq_start);
1085
1086 static void *ping_v4_seq_start(struct seq_file *seq, loff_t *pos)
1087 {
1088 return ping_seq_start(seq, pos, AF_INET);
1089 }
1090
1091 void *ping_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1092 {
1093 struct sock *sk;
1094
1095 if (v == SEQ_START_TOKEN)
1096 sk = ping_get_idx(seq, 0);
1097 else
1098 sk = ping_get_next(seq, v);
1099
1100 ++*pos;
1101 return sk;
1102 }
1103 EXPORT_SYMBOL_GPL(ping_seq_next);
1104
1105 void ping_seq_stop(struct seq_file *seq, void *v)
1106 __releases(ping_table.lock)
1107 {
1108 read_unlock_bh(&ping_table.lock);
1109 }
1110 EXPORT_SYMBOL_GPL(ping_seq_stop);
1111
1112 static void ping_v4_format_sock(struct sock *sp, struct seq_file *f,
1113 int bucket)
1114 {
1115 struct inet_sock *inet = inet_sk(sp);
1116 __be32 dest = inet->inet_daddr;
1117 __be32 src = inet->inet_rcv_saddr;
1118 __u16 destp = ntohs(inet->inet_dport);
1119 __u16 srcp = ntohs(inet->inet_sport);
1120
1121 seq_printf(f, "%5d: %08X:%04X %08X:%04X"
1122 " %02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %d",
1123 bucket, src, srcp, dest, destp, sp->sk_state,
1124 sk_wmem_alloc_get(sp),
1125 sk_rmem_alloc_get(sp),
1126 0, 0L, 0,
1127 from_kuid_munged(seq_user_ns(f), sock_i_uid(sp)),
1128 0, sock_i_ino(sp),
1129 atomic_read(&sp->sk_refcnt), sp,
1130 atomic_read(&sp->sk_drops));
1131 }
1132
1133 static int ping_v4_seq_show(struct seq_file *seq, void *v)
1134 {
1135 seq_setwidth(seq, 127);
1136 if (v == SEQ_START_TOKEN)
1137 seq_puts(seq, " sl local_address rem_address st tx_queue "
1138 "rx_queue tr tm->when retrnsmt uid timeout "
1139 "inode ref pointer drops");
1140 else {
1141 struct ping_iter_state *state = seq->private;
1142
1143 ping_v4_format_sock(v, seq, state->bucket);
1144 }
1145 seq_pad(seq, '\n');
1146 return 0;
1147 }
1148
1149 static int ping_seq_open(struct inode *inode, struct file *file)
1150 {
1151 struct ping_seq_afinfo *afinfo = PDE_DATA(inode);
1152 return seq_open_net(inode, file, &afinfo->seq_ops,
1153 sizeof(struct ping_iter_state));
1154 }
1155
1156 const struct file_operations ping_seq_fops = {
1157 .open = ping_seq_open,
1158 .read = seq_read,
1159 .llseek = seq_lseek,
1160 .release = seq_release_net,
1161 };
1162 EXPORT_SYMBOL_GPL(ping_seq_fops);
1163
1164 static struct ping_seq_afinfo ping_v4_seq_afinfo = {
1165 .name = "icmp",
1166 .family = AF_INET,
1167 .seq_fops = &ping_seq_fops,
1168 .seq_ops = {
1169 .start = ping_v4_seq_start,
1170 .show = ping_v4_seq_show,
1171 .next = ping_seq_next,
1172 .stop = ping_seq_stop,
1173 },
1174 };
1175
1176 int ping_proc_register(struct net *net, struct ping_seq_afinfo *afinfo)
1177 {
1178 struct proc_dir_entry *p;
1179 p = proc_create_data(afinfo->name, S_IRUGO, net->proc_net,
1180 afinfo->seq_fops, afinfo);
1181 if (!p)
1182 return -ENOMEM;
1183 return 0;
1184 }
1185 EXPORT_SYMBOL_GPL(ping_proc_register);
1186
1187 void ping_proc_unregister(struct net *net, struct ping_seq_afinfo *afinfo)
1188 {
1189 remove_proc_entry(afinfo->name, net->proc_net);
1190 }
1191 EXPORT_SYMBOL_GPL(ping_proc_unregister);
1192
1193 static int __net_init ping_v4_proc_init_net(struct net *net)
1194 {
1195 return ping_proc_register(net, &ping_v4_seq_afinfo);
1196 }
1197
1198 static void __net_exit ping_v4_proc_exit_net(struct net *net)
1199 {
1200 ping_proc_unregister(net, &ping_v4_seq_afinfo);
1201 }
1202
1203 static struct pernet_operations ping_v4_net_ops = {
1204 .init = ping_v4_proc_init_net,
1205 .exit = ping_v4_proc_exit_net,
1206 };
1207
1208 int __init ping_proc_init(void)
1209 {
1210 return register_pernet_subsys(&ping_v4_net_ops);
1211 }
1212
1213 void ping_proc_exit(void)
1214 {
1215 unregister_pernet_subsys(&ping_v4_net_ops);
1216 }
1217
1218 #endif
1219
1220 void __init ping_init(void)
1221 {
1222 int i;
1223
1224 for (i = 0; i < PING_HTABLE_SIZE; i++)
1225 INIT_HLIST_NULLS_HEAD(&ping_table.hash[i], i);
1226 rwlock_init(&ping_table.lock);
1227 }
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