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Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux...
[linux/fpc-iii.git] / net / ipv4 / ping.c
blobcf9700b1a1061404abb62c906afac1cacb43657a
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, j, count;
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 count = group_info->ngroups;
274 for (i = 0; i < group_info->nblocks; i++) {
275 int cp_count = min_t(int, NGROUPS_PER_BLOCK, count);
276 for (j = 0; j < cp_count; j++) {
277 kgid_t gid = group_info->blocks[i][j];
278 if (gid_lte(low, gid) && gid_lte(gid, high))
279 goto out_release_group;
280 }
281
282 count -= cp_count;
283 }
284
285 ret = -EACCES;
286
287 out_release_group:
288 put_group_info(group_info);
289 return ret;
290 }
291 EXPORT_SYMBOL_GPL(ping_init_sock);
292
293 void ping_close(struct sock *sk, long timeout)
294 {
295 pr_debug("ping_close(sk=%p,sk->num=%u)\n",
296 inet_sk(sk), inet_sk(sk)->inet_num);
297 pr_debug("isk->refcnt = %d\n", sk->sk_refcnt.counter);
298
299 sk_common_release(sk);
300 }
301 EXPORT_SYMBOL_GPL(ping_close);
302
303 /* Checks the bind address and possibly modifies sk->sk_bound_dev_if. */
304 static int ping_check_bind_addr(struct sock *sk, struct inet_sock *isk,
305 struct sockaddr *uaddr, int addr_len) {
306 struct net *net = sock_net(sk);
307 if (sk->sk_family == AF_INET) {
308 struct sockaddr_in *addr = (struct sockaddr_in *) uaddr;
309 int chk_addr_ret;
310
311 if (addr_len < sizeof(*addr))
312 return -EINVAL;
313
314 if (addr->sin_family != AF_INET &&
315 !(addr->sin_family == AF_UNSPEC &&
316 addr->sin_addr.s_addr == htonl(INADDR_ANY)))
317 return -EAFNOSUPPORT;
318
319 pr_debug("ping_check_bind_addr(sk=%p,addr=%pI4,port=%d)\n",
320 sk, &addr->sin_addr.s_addr, ntohs(addr->sin_port));
321
322 chk_addr_ret = inet_addr_type(net, addr->sin_addr.s_addr);
323
324 if (addr->sin_addr.s_addr == htonl(INADDR_ANY))
325 chk_addr_ret = RTN_LOCAL;
326
327 if ((net->ipv4.sysctl_ip_nonlocal_bind == 0 &&
328 isk->freebind == 0 && isk->transparent == 0 &&
329 chk_addr_ret != RTN_LOCAL) ||
330 chk_addr_ret == RTN_MULTICAST ||
331 chk_addr_ret == RTN_BROADCAST)
332 return -EADDRNOTAVAIL;
333
334 #if IS_ENABLED(CONFIG_IPV6)
335 } else if (sk->sk_family == AF_INET6) {
336 struct sockaddr_in6 *addr = (struct sockaddr_in6 *) uaddr;
337 int addr_type, scoped, has_addr;
338 struct net_device *dev = NULL;
339
340 if (addr_len < sizeof(*addr))
341 return -EINVAL;
342
343 if (addr->sin6_family != AF_INET6)
344 return -EAFNOSUPPORT;
345
346 pr_debug("ping_check_bind_addr(sk=%p,addr=%pI6c,port=%d)\n",
347 sk, addr->sin6_addr.s6_addr, ntohs(addr->sin6_port));
348
349 addr_type = ipv6_addr_type(&addr->sin6_addr);
350 scoped = __ipv6_addr_needs_scope_id(addr_type);
351 if ((addr_type != IPV6_ADDR_ANY &&
352 !(addr_type & IPV6_ADDR_UNICAST)) ||
353 (scoped && !addr->sin6_scope_id))
354 return -EINVAL;
355
356 rcu_read_lock();
357 if (addr->sin6_scope_id) {
358 dev = dev_get_by_index_rcu(net, addr->sin6_scope_id);
359 if (!dev) {
360 rcu_read_unlock();
361 return -ENODEV;
362 }
363 }
364 has_addr = pingv6_ops.ipv6_chk_addr(net, &addr->sin6_addr, dev,
365 scoped);
366 rcu_read_unlock();
367
368 if (!(net->ipv6.sysctl.ip_nonlocal_bind ||
369 isk->freebind || isk->transparent || has_addr ||
370 addr_type == IPV6_ADDR_ANY))
371 return -EADDRNOTAVAIL;
372
373 if (scoped)
374 sk->sk_bound_dev_if = addr->sin6_scope_id;
375 #endif
376 } else {
377 return -EAFNOSUPPORT;
378 }
379 return 0;
380 }
381
382 static void ping_set_saddr(struct sock *sk, struct sockaddr *saddr)
383 {
384 if (saddr->sa_family == AF_INET) {
385 struct inet_sock *isk = inet_sk(sk);
386 struct sockaddr_in *addr = (struct sockaddr_in *) saddr;
387 isk->inet_rcv_saddr = isk->inet_saddr = addr->sin_addr.s_addr;
388 #if IS_ENABLED(CONFIG_IPV6)
389 } else if (saddr->sa_family == AF_INET6) {
390 struct sockaddr_in6 *addr = (struct sockaddr_in6 *) saddr;
391 struct ipv6_pinfo *np = inet6_sk(sk);
392 sk->sk_v6_rcv_saddr = np->saddr = addr->sin6_addr;
393 #endif
394 }
395 }
396
397 static void ping_clear_saddr(struct sock *sk, int dif)
398 {
399 sk->sk_bound_dev_if = dif;
400 if (sk->sk_family == AF_INET) {
401 struct inet_sock *isk = inet_sk(sk);
402 isk->inet_rcv_saddr = isk->inet_saddr = 0;
403 #if IS_ENABLED(CONFIG_IPV6)
404 } else if (sk->sk_family == AF_INET6) {
405 struct ipv6_pinfo *np = inet6_sk(sk);
406 memset(&sk->sk_v6_rcv_saddr, 0, sizeof(sk->sk_v6_rcv_saddr));
407 memset(&np->saddr, 0, sizeof(np->saddr));
408 #endif
409 }
410 }
411 /*
412 * We need our own bind because there are no privileged id's == local ports.
413 * Moreover, we don't allow binding to multi- and broadcast addresses.
414 */
415
416 int ping_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len)
417 {
418 struct inet_sock *isk = inet_sk(sk);
419 unsigned short snum;
420 int err;
421 int dif = sk->sk_bound_dev_if;
422
423 err = ping_check_bind_addr(sk, isk, uaddr, addr_len);
424 if (err)
425 return err;
426
427 lock_sock(sk);
428
429 err = -EINVAL;
430 if (isk->inet_num != 0)
431 goto out;
432
433 err = -EADDRINUSE;
434 ping_set_saddr(sk, uaddr);
435 snum = ntohs(((struct sockaddr_in *)uaddr)->sin_port);
436 if (ping_get_port(sk, snum) != 0) {
437 ping_clear_saddr(sk, dif);
438 goto out;
439 }
440
441 pr_debug("after bind(): num = %d, dif = %d\n",
442 (int)isk->inet_num,
443 (int)sk->sk_bound_dev_if);
444
445 err = 0;
446 if (sk->sk_family == AF_INET && isk->inet_rcv_saddr)
447 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
448 #if IS_ENABLED(CONFIG_IPV6)
449 if (sk->sk_family == AF_INET6 && !ipv6_addr_any(&sk->sk_v6_rcv_saddr))
450 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
451 #endif
452
453 if (snum)
454 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
455 isk->inet_sport = htons(isk->inet_num);
456 isk->inet_daddr = 0;
457 isk->inet_dport = 0;
458
459 #if IS_ENABLED(CONFIG_IPV6)
460 if (sk->sk_family == AF_INET6)
461 memset(&sk->sk_v6_daddr, 0, sizeof(sk->sk_v6_daddr));
462 #endif
463
464 sk_dst_reset(sk);
465 out:
466 release_sock(sk);
467 pr_debug("ping_v4_bind -> %d\n", err);
468 return err;
469 }
470 EXPORT_SYMBOL_GPL(ping_bind);
471
472 /*
473 * Is this a supported type of ICMP message?
474 */
475
476 static inline int ping_supported(int family, int type, int code)
477 {
478 return (family == AF_INET && type == ICMP_ECHO && code == 0) ||
479 (family == AF_INET6 && type == ICMPV6_ECHO_REQUEST && code == 0);
480 }
481
482 /*
483 * This routine is called by the ICMP module when it gets some
484 * sort of error condition.
485 */
486
487 void ping_err(struct sk_buff *skb, int offset, u32 info)
488 {
489 int family;
490 struct icmphdr *icmph;
491 struct inet_sock *inet_sock;
492 int type;
493 int code;
494 struct net *net = dev_net(skb->dev);
495 struct sock *sk;
496 int harderr;
497 int err;
498
499 if (skb->protocol == htons(ETH_P_IP)) {
500 family = AF_INET;
501 type = icmp_hdr(skb)->type;
502 code = icmp_hdr(skb)->code;
503 icmph = (struct icmphdr *)(skb->data + offset);
504 } else if (skb->protocol == htons(ETH_P_IPV6)) {
505 family = AF_INET6;
506 type = icmp6_hdr(skb)->icmp6_type;
507 code = icmp6_hdr(skb)->icmp6_code;
508 icmph = (struct icmphdr *) (skb->data + offset);
509 } else {
510 BUG();
511 }
512
513 /* We assume the packet has already been checked by icmp_unreach */
514
515 if (!ping_supported(family, icmph->type, icmph->code))
516 return;
517
518 pr_debug("ping_err(proto=0x%x,type=%d,code=%d,id=%04x,seq=%04x)\n",
519 skb->protocol, type, code, ntohs(icmph->un.echo.id),
520 ntohs(icmph->un.echo.sequence));
521
522 sk = ping_lookup(net, skb, ntohs(icmph->un.echo.id));
523 if (!sk) {
524 pr_debug("no socket, dropping\n");
525 return; /* No socket for error */
526 }
527 pr_debug("err on socket %p\n", sk);
528
529 err = 0;
530 harderr = 0;
531 inet_sock = inet_sk(sk);
532
533 if (skb->protocol == htons(ETH_P_IP)) {
534 switch (type) {
535 default:
536 case ICMP_TIME_EXCEEDED:
537 err = EHOSTUNREACH;
538 break;
539 case ICMP_SOURCE_QUENCH:
540 /* This is not a real error but ping wants to see it.
541 * Report it with some fake errno.
542 */
543 err = EREMOTEIO;
544 break;
545 case ICMP_PARAMETERPROB:
546 err = EPROTO;
547 harderr = 1;
548 break;
549 case ICMP_DEST_UNREACH:
550 if (code == ICMP_FRAG_NEEDED) { /* Path MTU discovery */
551 ipv4_sk_update_pmtu(skb, sk, info);
552 if (inet_sock->pmtudisc != IP_PMTUDISC_DONT) {
553 err = EMSGSIZE;
554 harderr = 1;
555 break;
556 }
557 goto out;
558 }
559 err = EHOSTUNREACH;
560 if (code <= NR_ICMP_UNREACH) {
561 harderr = icmp_err_convert[code].fatal;
562 err = icmp_err_convert[code].errno;
563 }
564 break;
565 case ICMP_REDIRECT:
566 /* See ICMP_SOURCE_QUENCH */
567 ipv4_sk_redirect(skb, sk);
568 err = EREMOTEIO;
569 break;
570 }
571 #if IS_ENABLED(CONFIG_IPV6)
572 } else if (skb->protocol == htons(ETH_P_IPV6)) {
573 harderr = pingv6_ops.icmpv6_err_convert(type, code, &err);
574 #endif
575 }
576
577 /*
578 * RFC1122: OK. Passes ICMP errors back to application, as per
579 * 4.1.3.3.
580 */
581 if ((family == AF_INET && !inet_sock->recverr) ||
582 (family == AF_INET6 && !inet6_sk(sk)->recverr)) {
583 if (!harderr || sk->sk_state != TCP_ESTABLISHED)
584 goto out;
585 } else {
586 if (family == AF_INET) {
587 ip_icmp_error(sk, skb, err, 0 /* no remote port */,
588 info, (u8 *)icmph);
589 #if IS_ENABLED(CONFIG_IPV6)
590 } else if (family == AF_INET6) {
591 pingv6_ops.ipv6_icmp_error(sk, skb, err, 0,
592 info, (u8 *)icmph);
593 #endif
594 }
595 }
596 sk->sk_err = err;
597 sk->sk_error_report(sk);
598 out:
599 sock_put(sk);
600 }
601 EXPORT_SYMBOL_GPL(ping_err);
602
603 /*
604 * Copy and checksum an ICMP Echo packet from user space into a buffer
605 * starting from the payload.
606 */
607
608 int ping_getfrag(void *from, char *to,
609 int offset, int fraglen, int odd, struct sk_buff *skb)
610 {
611 struct pingfakehdr *pfh = (struct pingfakehdr *)from;
612
613 if (offset == 0) {
614 fraglen -= sizeof(struct icmphdr);
615 if (fraglen < 0)
616 BUG();
617 if (csum_and_copy_from_iter(to + sizeof(struct icmphdr),
618 fraglen, &pfh->wcheck,
619 &pfh->msg->msg_iter) != fraglen)
620 return -EFAULT;
621 } else if (offset < sizeof(struct icmphdr)) {
622 BUG();
623 } else {
624 if (csum_and_copy_from_iter(to, fraglen, &pfh->wcheck,
625 &pfh->msg->msg_iter) != fraglen)
626 return -EFAULT;
627 }
628
629 #if IS_ENABLED(CONFIG_IPV6)
630 /* For IPv6, checksum each skb as we go along, as expected by
631 * icmpv6_push_pending_frames. For IPv4, accumulate the checksum in
632 * wcheck, it will be finalized in ping_v4_push_pending_frames.
633 */
634 if (pfh->family == AF_INET6) {
635 skb->csum = pfh->wcheck;
636 skb->ip_summed = CHECKSUM_NONE;
637 pfh->wcheck = 0;
638 }
639 #endif
640
641 return 0;
642 }
643 EXPORT_SYMBOL_GPL(ping_getfrag);
644
645 static int ping_v4_push_pending_frames(struct sock *sk, struct pingfakehdr *pfh,
646 struct flowi4 *fl4)
647 {
648 struct sk_buff *skb = skb_peek(&sk->sk_write_queue);
649
650 pfh->wcheck = csum_partial((char *)&pfh->icmph,
651 sizeof(struct icmphdr), pfh->wcheck);
652 pfh->icmph.checksum = csum_fold(pfh->wcheck);
653 memcpy(icmp_hdr(skb), &pfh->icmph, sizeof(struct icmphdr));
654 skb->ip_summed = CHECKSUM_NONE;
655 return ip_push_pending_frames(sk, fl4);
656 }
657
658 int ping_common_sendmsg(int family, struct msghdr *msg, size_t len,
659 void *user_icmph, size_t icmph_len) {
660 u8 type, code;
661
662 if (len > 0xFFFF)
663 return -EMSGSIZE;
664
665 /*
666 * Check the flags.
667 */
668
669 /* Mirror BSD error message compatibility */
670 if (msg->msg_flags & MSG_OOB)
671 return -EOPNOTSUPP;
672
673 /*
674 * Fetch the ICMP header provided by the userland.
675 * iovec is modified! The ICMP header is consumed.
676 */
677 if (memcpy_from_msg(user_icmph, msg, icmph_len))
678 return -EFAULT;
679
680 if (family == AF_INET) {
681 type = ((struct icmphdr *) user_icmph)->type;
682 code = ((struct icmphdr *) user_icmph)->code;
683 #if IS_ENABLED(CONFIG_IPV6)
684 } else if (family == AF_INET6) {
685 type = ((struct icmp6hdr *) user_icmph)->icmp6_type;
686 code = ((struct icmp6hdr *) user_icmph)->icmp6_code;
687 #endif
688 } else {
689 BUG();
690 }
691
692 if (!ping_supported(family, type, code))
693 return -EINVAL;
694
695 return 0;
696 }
697 EXPORT_SYMBOL_GPL(ping_common_sendmsg);
698
699 static int ping_v4_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
700 {
701 struct net *net = sock_net(sk);
702 struct flowi4 fl4;
703 struct inet_sock *inet = inet_sk(sk);
704 struct ipcm_cookie ipc;
705 struct icmphdr user_icmph;
706 struct pingfakehdr pfh;
707 struct rtable *rt = NULL;
708 struct ip_options_data opt_copy;
709 int free = 0;
710 __be32 saddr, daddr, faddr;
711 u8 tos;
712 int err;
713
714 pr_debug("ping_v4_sendmsg(sk=%p,sk->num=%u)\n", inet, inet->inet_num);
715
716 err = ping_common_sendmsg(AF_INET, msg, len, &user_icmph,
717 sizeof(user_icmph));
718 if (err)
719 return err;
720
721 /*
722 * Get and verify the address.
723 */
724
725 if (msg->msg_name) {
726 DECLARE_SOCKADDR(struct sockaddr_in *, usin, msg->msg_name);
727 if (msg->msg_namelen < sizeof(*usin))
728 return -EINVAL;
729 if (usin->sin_family != AF_INET)
730 return -EAFNOSUPPORT;
731 daddr = usin->sin_addr.s_addr;
732 /* no remote port */
733 } else {
734 if (sk->sk_state != TCP_ESTABLISHED)
735 return -EDESTADDRREQ;
736 daddr = inet->inet_daddr;
737 /* no remote port */
738 }
739
740 ipc.addr = inet->inet_saddr;
741 ipc.opt = NULL;
742 ipc.oif = sk->sk_bound_dev_if;
743 ipc.tx_flags = 0;
744 ipc.ttl = 0;
745 ipc.tos = -1;
746
747 sock_tx_timestamp(sk, &ipc.tx_flags);
748
749 if (msg->msg_controllen) {
750 err = ip_cmsg_send(sock_net(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 saddr = ipc.addr;
772 ipc.addr = faddr = daddr;
773
774 if (ipc.opt && ipc.opt->opt.srr) {
775 if (!daddr)
776 return -EINVAL;
777 faddr = ipc.opt->opt.faddr;
778 }
779 tos = get_rttos(&ipc, inet);
780 if (sock_flag(sk, SOCK_LOCALROUTE) ||
781 (msg->msg_flags & MSG_DONTROUTE) ||
782 (ipc.opt && ipc.opt->opt.is_strictroute)) {
783 tos |= RTO_ONLINK;
784 }
785
786 if (ipv4_is_multicast(daddr)) {
787 if (!ipc.oif)
788 ipc.oif = inet->mc_index;
789 if (!saddr)
790 saddr = inet->mc_addr;
791 } else if (!ipc.oif)
792 ipc.oif = inet->uc_index;
793
794 flowi4_init_output(&fl4, ipc.oif, sk->sk_mark, tos,
795 RT_SCOPE_UNIVERSE, sk->sk_protocol,
796 inet_sk_flowi_flags(sk), faddr, saddr, 0, 0);
797
798 security_sk_classify_flow(sk, flowi4_to_flowi(&fl4));
799 rt = ip_route_output_flow(net, &fl4, sk);
800 if (IS_ERR(rt)) {
801 err = PTR_ERR(rt);
802 rt = NULL;
803 if (err == -ENETUNREACH)
804 IP_INC_STATS(net, IPSTATS_MIB_OUTNOROUTES);
805 goto out;
806 }
807
808 err = -EACCES;
809 if ((rt->rt_flags & RTCF_BROADCAST) &&
810 !sock_flag(sk, SOCK_BROADCAST))
811 goto out;
812
813 if (msg->msg_flags & MSG_CONFIRM)
814 goto do_confirm;
815 back_from_confirm:
816
817 if (!ipc.addr)
818 ipc.addr = fl4.daddr;
819
820 lock_sock(sk);
821
822 pfh.icmph.type = user_icmph.type; /* already checked */
823 pfh.icmph.code = user_icmph.code; /* ditto */
824 pfh.icmph.checksum = 0;
825 pfh.icmph.un.echo.id = inet->inet_sport;
826 pfh.icmph.un.echo.sequence = user_icmph.un.echo.sequence;
827 pfh.msg = msg;
828 pfh.wcheck = 0;
829 pfh.family = AF_INET;
830
831 err = ip_append_data(sk, &fl4, ping_getfrag, &pfh, len,
832 0, &ipc, &rt, msg->msg_flags);
833 if (err)
834 ip_flush_pending_frames(sk);
835 else
836 err = ping_v4_push_pending_frames(sk, &pfh, &fl4);
837 release_sock(sk);
838
839 out:
840 ip_rt_put(rt);
841 if (free)
842 kfree(ipc.opt);
843 if (!err) {
844 icmp_out_count(sock_net(sk), user_icmph.type);
845 return len;
846 }
847 return err;
848
849 do_confirm:
850 dst_confirm(&rt->dst);
851 if (!(msg->msg_flags & MSG_PROBE) || len)
852 goto back_from_confirm;
853 err = 0;
854 goto out;
855 }
856
857 int ping_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int noblock,
858 int flags, int *addr_len)
859 {
860 struct inet_sock *isk = inet_sk(sk);
861 int family = sk->sk_family;
862 struct sk_buff *skb;
863 int copied, err;
864
865 pr_debug("ping_recvmsg(sk=%p,sk->num=%u)\n", isk, isk->inet_num);
866
867 err = -EOPNOTSUPP;
868 if (flags & MSG_OOB)
869 goto out;
870
871 if (flags & MSG_ERRQUEUE)
872 return inet_recv_error(sk, msg, len, addr_len);
873
874 skb = skb_recv_datagram(sk, flags, noblock, &err);
875 if (!skb)
876 goto out;
877
878 copied = skb->len;
879 if (copied > len) {
880 msg->msg_flags |= MSG_TRUNC;
881 copied = len;
882 }
883
884 /* Don't bother checking the checksum */
885 err = skb_copy_datagram_msg(skb, 0, msg, copied);
886 if (err)
887 goto done;
888
889 sock_recv_timestamp(msg, sk, skb);
890
891 /* Copy the address and add cmsg data. */
892 if (family == AF_INET) {
893 DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name);
894
895 if (sin) {
896 sin->sin_family = AF_INET;
897 sin->sin_port = 0 /* skb->h.uh->source */;
898 sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
899 memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
900 *addr_len = sizeof(*sin);
901 }
902
903 if (isk->cmsg_flags)
904 ip_cmsg_recv(msg, skb);
905
906 #if IS_ENABLED(CONFIG_IPV6)
907 } else if (family == AF_INET6) {
908 struct ipv6_pinfo *np = inet6_sk(sk);
909 struct ipv6hdr *ip6 = ipv6_hdr(skb);
910 DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
911
912 if (sin6) {
913 sin6->sin6_family = AF_INET6;
914 sin6->sin6_port = 0;
915 sin6->sin6_addr = ip6->saddr;
916 sin6->sin6_flowinfo = 0;
917 if (np->sndflow)
918 sin6->sin6_flowinfo = ip6_flowinfo(ip6);
919 sin6->sin6_scope_id =
920 ipv6_iface_scope_id(&sin6->sin6_addr,
921 inet6_iif(skb));
922 *addr_len = sizeof(*sin6);
923 }
924
925 if (inet6_sk(sk)->rxopt.all)
926 pingv6_ops.ip6_datagram_recv_common_ctl(sk, msg, skb);
927 if (skb->protocol == htons(ETH_P_IPV6) &&
928 inet6_sk(sk)->rxopt.all)
929 pingv6_ops.ip6_datagram_recv_specific_ctl(sk, msg, skb);
930 else if (skb->protocol == htons(ETH_P_IP) && isk->cmsg_flags)
931 ip_cmsg_recv(msg, skb);
932 #endif
933 } else {
934 BUG();
935 }
936
937 err = copied;
938
939 done:
940 skb_free_datagram(sk, skb);
941 out:
942 pr_debug("ping_recvmsg -> %d\n", err);
943 return err;
944 }
945 EXPORT_SYMBOL_GPL(ping_recvmsg);
946
947 int ping_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
948 {
949 pr_debug("ping_queue_rcv_skb(sk=%p,sk->num=%d,skb=%p)\n",
950 inet_sk(sk), inet_sk(sk)->inet_num, skb);
951 if (sock_queue_rcv_skb(sk, skb) < 0) {
952 kfree_skb(skb);
953 pr_debug("ping_queue_rcv_skb -> failed\n");
954 return -1;
955 }
956 return 0;
957 }
958 EXPORT_SYMBOL_GPL(ping_queue_rcv_skb);
959
960
961 /*
962 * All we need to do is get the socket.
963 */
964
965 bool ping_rcv(struct sk_buff *skb)
966 {
967 struct sock *sk;
968 struct net *net = dev_net(skb->dev);
969 struct icmphdr *icmph = icmp_hdr(skb);
970
971 /* We assume the packet has already been checked by icmp_rcv */
972
973 pr_debug("ping_rcv(skb=%p,id=%04x,seq=%04x)\n",
974 skb, ntohs(icmph->un.echo.id), ntohs(icmph->un.echo.sequence));
975
976 /* Push ICMP header back */
977 skb_push(skb, skb->data - (u8 *)icmph);
978
979 sk = ping_lookup(net, skb, ntohs(icmph->un.echo.id));
980 if (sk) {
981 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
982
983 pr_debug("rcv on socket %p\n", sk);
984 if (skb2)
985 ping_queue_rcv_skb(sk, skb2);
986 sock_put(sk);
987 return true;
988 }
989 pr_debug("no socket, dropping\n");
990
991 return false;
992 }
993 EXPORT_SYMBOL_GPL(ping_rcv);
994
995 struct proto ping_prot = {
996 .name = "PING",
997 .owner = THIS_MODULE,
998 .init = ping_init_sock,
999 .close = ping_close,
1000 .connect = ip4_datagram_connect,
1001 .disconnect = udp_disconnect,
1002 .setsockopt = ip_setsockopt,
1003 .getsockopt = ip_getsockopt,
1004 .sendmsg = ping_v4_sendmsg,
1005 .recvmsg = ping_recvmsg,
1006 .bind = ping_bind,
1007 .backlog_rcv = ping_queue_rcv_skb,
1008 .release_cb = ip4_datagram_release_cb,
1009 .hash = ping_hash,
1010 .unhash = ping_unhash,
1011 .get_port = ping_get_port,
1012 .obj_size = sizeof(struct inet_sock),
1013 };
1014 EXPORT_SYMBOL(ping_prot);
1015
1016 #ifdef CONFIG_PROC_FS
1017
1018 static struct sock *ping_get_first(struct seq_file *seq, int start)
1019 {
1020 struct sock *sk;
1021 struct ping_iter_state *state = seq->private;
1022 struct net *net = seq_file_net(seq);
1023
1024 for (state->bucket = start; state->bucket < PING_HTABLE_SIZE;
1025 ++state->bucket) {
1026 struct hlist_nulls_node *node;
1027 struct hlist_nulls_head *hslot;
1028
1029 hslot = &ping_table.hash[state->bucket];
1030
1031 if (hlist_nulls_empty(hslot))
1032 continue;
1033
1034 sk_nulls_for_each(sk, node, hslot) {
1035 if (net_eq(sock_net(sk), net) &&
1036 sk->sk_family == state->family)
1037 goto found;
1038 }
1039 }
1040 sk = NULL;
1041 found:
1042 return sk;
1043 }
1044
1045 static struct sock *ping_get_next(struct seq_file *seq, struct sock *sk)
1046 {
1047 struct ping_iter_state *state = seq->private;
1048 struct net *net = seq_file_net(seq);
1049
1050 do {
1051 sk = sk_nulls_next(sk);
1052 } while (sk && (!net_eq(sock_net(sk), net)));
1053
1054 if (!sk)
1055 return ping_get_first(seq, state->bucket + 1);
1056 return sk;
1057 }
1058
1059 static struct sock *ping_get_idx(struct seq_file *seq, loff_t pos)
1060 {
1061 struct sock *sk = ping_get_first(seq, 0);
1062
1063 if (sk)
1064 while (pos && (sk = ping_get_next(seq, sk)) != NULL)
1065 --pos;
1066 return pos ? NULL : sk;
1067 }
1068
1069 void *ping_seq_start(struct seq_file *seq, loff_t *pos, sa_family_t family)
1070 __acquires(ping_table.lock)
1071 {
1072 struct ping_iter_state *state = seq->private;
1073 state->bucket = 0;
1074 state->family = family;
1075
1076 read_lock_bh(&ping_table.lock);
1077
1078 return *pos ? ping_get_idx(seq, *pos-1) : SEQ_START_TOKEN;
1079 }
1080 EXPORT_SYMBOL_GPL(ping_seq_start);
1081
1082 static void *ping_v4_seq_start(struct seq_file *seq, loff_t *pos)
1083 {
1084 return ping_seq_start(seq, pos, AF_INET);
1085 }
1086
1087 void *ping_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1088 {
1089 struct sock *sk;
1090
1091 if (v == SEQ_START_TOKEN)
1092 sk = ping_get_idx(seq, 0);
1093 else
1094 sk = ping_get_next(seq, v);
1095
1096 ++*pos;
1097 return sk;
1098 }
1099 EXPORT_SYMBOL_GPL(ping_seq_next);
1100
1101 void ping_seq_stop(struct seq_file *seq, void *v)
1102 __releases(ping_table.lock)
1103 {
1104 read_unlock_bh(&ping_table.lock);
1105 }
1106 EXPORT_SYMBOL_GPL(ping_seq_stop);
1107
1108 static void ping_v4_format_sock(struct sock *sp, struct seq_file *f,
1109 int bucket)
1110 {
1111 struct inet_sock *inet = inet_sk(sp);
1112 __be32 dest = inet->inet_daddr;
1113 __be32 src = inet->inet_rcv_saddr;
1114 __u16 destp = ntohs(inet->inet_dport);
1115 __u16 srcp = ntohs(inet->inet_sport);
1116
1117 seq_printf(f, "%5d: %08X:%04X %08X:%04X"
1118 " %02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %d",
1119 bucket, src, srcp, dest, destp, sp->sk_state,
1120 sk_wmem_alloc_get(sp),
1121 sk_rmem_alloc_get(sp),
1122 0, 0L, 0,
1123 from_kuid_munged(seq_user_ns(f), sock_i_uid(sp)),
1124 0, sock_i_ino(sp),
1125 atomic_read(&sp->sk_refcnt), sp,
1126 atomic_read(&sp->sk_drops));
1127 }
1128
1129 static int ping_v4_seq_show(struct seq_file *seq, void *v)
1130 {
1131 seq_setwidth(seq, 127);
1132 if (v == SEQ_START_TOKEN)
1133 seq_puts(seq, " sl local_address rem_address st tx_queue "
1134 "rx_queue tr tm->when retrnsmt uid timeout "
1135 "inode ref pointer drops");
1136 else {
1137 struct ping_iter_state *state = seq->private;
1138
1139 ping_v4_format_sock(v, seq, state->bucket);
1140 }
1141 seq_pad(seq, '\n');
1142 return 0;
1143 }
1144
1145 static int ping_seq_open(struct inode *inode, struct file *file)
1146 {
1147 struct ping_seq_afinfo *afinfo = PDE_DATA(inode);
1148 return seq_open_net(inode, file, &afinfo->seq_ops,
1149 sizeof(struct ping_iter_state));
1150 }
1151
1152 const struct file_operations ping_seq_fops = {
1153 .open = ping_seq_open,
1154 .read = seq_read,
1155 .llseek = seq_lseek,
1156 .release = seq_release_net,
1157 };
1158 EXPORT_SYMBOL_GPL(ping_seq_fops);
1159
1160 static struct ping_seq_afinfo ping_v4_seq_afinfo = {
1161 .name = "icmp",
1162 .family = AF_INET,
1163 .seq_fops = &ping_seq_fops,
1164 .seq_ops = {
1165 .start = ping_v4_seq_start,
1166 .show = ping_v4_seq_show,
1167 .next = ping_seq_next,
1168 .stop = ping_seq_stop,
1169 },
1170 };
1171
1172 int ping_proc_register(struct net *net, struct ping_seq_afinfo *afinfo)
1173 {
1174 struct proc_dir_entry *p;
1175 p = proc_create_data(afinfo->name, S_IRUGO, net->proc_net,
1176 afinfo->seq_fops, afinfo);
1177 if (!p)
1178 return -ENOMEM;
1179 return 0;
1180 }
1181 EXPORT_SYMBOL_GPL(ping_proc_register);
1182
1183 void ping_proc_unregister(struct net *net, struct ping_seq_afinfo *afinfo)
1184 {
1185 remove_proc_entry(afinfo->name, net->proc_net);
1186 }
1187 EXPORT_SYMBOL_GPL(ping_proc_unregister);
1188
1189 static int __net_init ping_v4_proc_init_net(struct net *net)
1190 {
1191 return ping_proc_register(net, &ping_v4_seq_afinfo);
1192 }
1193
1194 static void __net_exit ping_v4_proc_exit_net(struct net *net)
1195 {
1196 ping_proc_unregister(net, &ping_v4_seq_afinfo);
1197 }
1198
1199 static struct pernet_operations ping_v4_net_ops = {
1200 .init = ping_v4_proc_init_net,
1201 .exit = ping_v4_proc_exit_net,
1202 };
1203
1204 int __init ping_proc_init(void)
1205 {
1206 return register_pernet_subsys(&ping_v4_net_ops);
1207 }
1208
1209 void ping_proc_exit(void)
1210 {
1211 unregister_pernet_subsys(&ping_v4_net_ops);
1212 }
1213
1214 #endif
1215
1216 void __init ping_init(void)
1217 {
1218 int i;
1219
1220 for (i = 0; i < PING_HTABLE_SIZE; i++)
1221 INIT_HLIST_NULLS_HEAD(&ping_table.hash[i], i);
1222 rwlock_init(&ping_table.lock);
1223 }
Linux with added FPC-III support