Linux 3.8-rc7
[cris-mirror.git] / net / ipv4 / ping.c
blob6f9c07268cf6d433379898421e978d74fa49952f
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.
6 * "Ping" sockets
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.
13 * Based on ipv4/udp.c code.
15 * Authors: Vasiliy Kulikov / Openwall (for Linux 2.6),
16 * Pavel Kankovsky (for Linux 2.4.32)
18 * Pavel gave all rights to bugs to Vasiliy,
19 * none of the bugs are Pavel's now.
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/ipv6.h>
37 #include <net/icmp.h>
38 #include <net/protocol.h>
39 #include <linux/skbuff.h>
40 #include <linux/proc_fs.h>
41 #include <linux/export.h>
42 #include <net/sock.h>
43 #include <net/ping.h>
44 #include <net/udp.h>
45 #include <net/route.h>
46 #include <net/inet_common.h>
47 #include <net/checksum.h>
50 static struct ping_table ping_table;
52 static u16 ping_port_rover;
54 static inline int ping_hashfn(struct net *net, unsigned int num, unsigned int mask)
56 int res = (num + net_hash_mix(net)) & mask;
58 pr_debug("hash(%d) = %d\n", num, res);
59 return res;
62 static inline struct hlist_nulls_head *ping_hashslot(struct ping_table *table,
63 struct net *net, unsigned int num)
65 return &table->hash[ping_hashfn(net, num, PING_HTABLE_MASK)];
68 static int ping_v4_get_port(struct sock *sk, unsigned short ident)
70 struct hlist_nulls_node *node;
71 struct hlist_nulls_head *hlist;
72 struct inet_sock *isk, *isk2;
73 struct sock *sk2 = NULL;
75 isk = inet_sk(sk);
76 write_lock_bh(&ping_table.lock);
77 if (ident == 0) {
78 u32 i;
79 u16 result = ping_port_rover + 1;
81 for (i = 0; i < (1L << 16); i++, result++) {
82 if (!result)
83 result++; /* avoid zero */
84 hlist = ping_hashslot(&ping_table, sock_net(sk),
85 result);
86 ping_portaddr_for_each_entry(sk2, node, hlist) {
87 isk2 = inet_sk(sk2);
89 if (isk2->inet_num == result)
90 goto next_port;
93 /* found */
94 ping_port_rover = ident = result;
95 break;
96 next_port:
99 if (i >= (1L << 16))
100 goto fail;
101 } else {
102 hlist = ping_hashslot(&ping_table, sock_net(sk), ident);
103 ping_portaddr_for_each_entry(sk2, node, hlist) {
104 isk2 = inet_sk(sk2);
106 if ((isk2->inet_num == ident) &&
107 (sk2 != sk) &&
108 (!sk2->sk_reuse || !sk->sk_reuse))
109 goto fail;
113 pr_debug("found port/ident = %d\n", ident);
114 isk->inet_num = ident;
115 if (sk_unhashed(sk)) {
116 pr_debug("was not hashed\n");
117 sock_hold(sk);
118 hlist_nulls_add_head(&sk->sk_nulls_node, hlist);
119 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
121 write_unlock_bh(&ping_table.lock);
122 return 0;
124 fail:
125 write_unlock_bh(&ping_table.lock);
126 return 1;
129 static void ping_v4_hash(struct sock *sk)
131 pr_debug("ping_v4_hash(sk->port=%u)\n", inet_sk(sk)->inet_num);
132 BUG(); /* "Please do not press this button again." */
135 static void ping_v4_unhash(struct sock *sk)
137 struct inet_sock *isk = inet_sk(sk);
138 pr_debug("ping_v4_unhash(isk=%p,isk->num=%u)\n", isk, isk->inet_num);
139 if (sk_hashed(sk)) {
140 write_lock_bh(&ping_table.lock);
141 hlist_nulls_del(&sk->sk_nulls_node);
142 sock_put(sk);
143 isk->inet_num = 0;
144 isk->inet_sport = 0;
145 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
146 write_unlock_bh(&ping_table.lock);
150 static struct sock *ping_v4_lookup(struct net *net, __be32 saddr, __be32 daddr,
151 u16 ident, int dif)
153 struct hlist_nulls_head *hslot = ping_hashslot(&ping_table, net, ident);
154 struct sock *sk = NULL;
155 struct inet_sock *isk;
156 struct hlist_nulls_node *hnode;
158 pr_debug("try to find: num = %d, daddr = %pI4, dif = %d\n",
159 (int)ident, &daddr, dif);
160 read_lock_bh(&ping_table.lock);
162 ping_portaddr_for_each_entry(sk, hnode, hslot) {
163 isk = inet_sk(sk);
165 pr_debug("found: %p: num = %d, daddr = %pI4, dif = %d\n", sk,
166 (int)isk->inet_num, &isk->inet_rcv_saddr,
167 sk->sk_bound_dev_if);
169 pr_debug("iterate\n");
170 if (isk->inet_num != ident)
171 continue;
172 if (isk->inet_rcv_saddr && isk->inet_rcv_saddr != daddr)
173 continue;
174 if (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif)
175 continue;
177 sock_hold(sk);
178 goto exit;
181 sk = NULL;
182 exit:
183 read_unlock_bh(&ping_table.lock);
185 return sk;
188 static void inet_get_ping_group_range_net(struct net *net, kgid_t *low,
189 kgid_t *high)
191 kgid_t *data = net->ipv4.sysctl_ping_group_range;
192 unsigned int seq;
194 do {
195 seq = read_seqbegin(&sysctl_local_ports.lock);
197 *low = data[0];
198 *high = data[1];
199 } while (read_seqretry(&sysctl_local_ports.lock, seq));
203 static int ping_init_sock(struct sock *sk)
205 struct net *net = sock_net(sk);
206 kgid_t group = current_egid();
207 struct group_info *group_info = get_current_groups();
208 int i, j, count = group_info->ngroups;
209 kgid_t low, high;
211 inet_get_ping_group_range_net(net, &low, &high);
212 if (gid_lte(low, group) && gid_lte(group, high))
213 return 0;
215 for (i = 0; i < group_info->nblocks; i++) {
216 int cp_count = min_t(int, NGROUPS_PER_BLOCK, count);
217 for (j = 0; j < cp_count; j++) {
218 kgid_t gid = group_info->blocks[i][j];
219 if (gid_lte(low, gid) && gid_lte(gid, high))
220 return 0;
223 count -= cp_count;
226 return -EACCES;
229 static void ping_close(struct sock *sk, long timeout)
231 pr_debug("ping_close(sk=%p,sk->num=%u)\n",
232 inet_sk(sk), inet_sk(sk)->inet_num);
233 pr_debug("isk->refcnt = %d\n", sk->sk_refcnt.counter);
235 sk_common_release(sk);
239 * We need our own bind because there are no privileged id's == local ports.
240 * Moreover, we don't allow binding to multi- and broadcast addresses.
243 static int ping_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len)
245 struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
246 struct inet_sock *isk = inet_sk(sk);
247 unsigned short snum;
248 int chk_addr_ret;
249 int err;
251 if (addr_len < sizeof(struct sockaddr_in))
252 return -EINVAL;
254 pr_debug("ping_v4_bind(sk=%p,sa_addr=%08x,sa_port=%d)\n",
255 sk, addr->sin_addr.s_addr, ntohs(addr->sin_port));
257 chk_addr_ret = inet_addr_type(sock_net(sk), addr->sin_addr.s_addr);
258 if (addr->sin_addr.s_addr == htonl(INADDR_ANY))
259 chk_addr_ret = RTN_LOCAL;
261 if ((sysctl_ip_nonlocal_bind == 0 &&
262 isk->freebind == 0 && isk->transparent == 0 &&
263 chk_addr_ret != RTN_LOCAL) ||
264 chk_addr_ret == RTN_MULTICAST ||
265 chk_addr_ret == RTN_BROADCAST)
266 return -EADDRNOTAVAIL;
268 lock_sock(sk);
270 err = -EINVAL;
271 if (isk->inet_num != 0)
272 goto out;
274 err = -EADDRINUSE;
275 isk->inet_rcv_saddr = isk->inet_saddr = addr->sin_addr.s_addr;
276 snum = ntohs(addr->sin_port);
277 if (ping_v4_get_port(sk, snum) != 0) {
278 isk->inet_saddr = isk->inet_rcv_saddr = 0;
279 goto out;
282 pr_debug("after bind(): num = %d, daddr = %pI4, dif = %d\n",
283 (int)isk->inet_num,
284 &isk->inet_rcv_saddr,
285 (int)sk->sk_bound_dev_if);
287 err = 0;
288 if (isk->inet_rcv_saddr)
289 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
290 if (snum)
291 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
292 isk->inet_sport = htons(isk->inet_num);
293 isk->inet_daddr = 0;
294 isk->inet_dport = 0;
295 sk_dst_reset(sk);
296 out:
297 release_sock(sk);
298 pr_debug("ping_v4_bind -> %d\n", err);
299 return err;
303 * Is this a supported type of ICMP message?
306 static inline int ping_supported(int type, int code)
308 if (type == ICMP_ECHO && code == 0)
309 return 1;
310 return 0;
314 * This routine is called by the ICMP module when it gets some
315 * sort of error condition.
318 static int ping_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
320 void ping_err(struct sk_buff *skb, u32 info)
322 struct iphdr *iph = (struct iphdr *)skb->data;
323 struct icmphdr *icmph = (struct icmphdr *)(skb->data+(iph->ihl<<2));
324 struct inet_sock *inet_sock;
325 int type = icmph->type;
326 int code = icmph->code;
327 struct net *net = dev_net(skb->dev);
328 struct sock *sk;
329 int harderr;
330 int err;
332 /* We assume the packet has already been checked by icmp_unreach */
334 if (!ping_supported(icmph->type, icmph->code))
335 return;
337 pr_debug("ping_err(type=%04x,code=%04x,id=%04x,seq=%04x)\n", type,
338 code, ntohs(icmph->un.echo.id), ntohs(icmph->un.echo.sequence));
340 sk = ping_v4_lookup(net, iph->daddr, iph->saddr,
341 ntohs(icmph->un.echo.id), skb->dev->ifindex);
342 if (sk == NULL) {
343 pr_debug("no socket, dropping\n");
344 return; /* No socket for error */
346 pr_debug("err on socket %p\n", sk);
348 err = 0;
349 harderr = 0;
350 inet_sock = inet_sk(sk);
352 switch (type) {
353 default:
354 case ICMP_TIME_EXCEEDED:
355 err = EHOSTUNREACH;
356 break;
357 case ICMP_SOURCE_QUENCH:
358 /* This is not a real error but ping wants to see it.
359 * Report it with some fake errno. */
360 err = EREMOTEIO;
361 break;
362 case ICMP_PARAMETERPROB:
363 err = EPROTO;
364 harderr = 1;
365 break;
366 case ICMP_DEST_UNREACH:
367 if (code == ICMP_FRAG_NEEDED) { /* Path MTU discovery */
368 ipv4_sk_update_pmtu(skb, sk, info);
369 if (inet_sock->pmtudisc != IP_PMTUDISC_DONT) {
370 err = EMSGSIZE;
371 harderr = 1;
372 break;
374 goto out;
376 err = EHOSTUNREACH;
377 if (code <= NR_ICMP_UNREACH) {
378 harderr = icmp_err_convert[code].fatal;
379 err = icmp_err_convert[code].errno;
381 break;
382 case ICMP_REDIRECT:
383 /* See ICMP_SOURCE_QUENCH */
384 ipv4_sk_redirect(skb, sk);
385 err = EREMOTEIO;
386 break;
390 * RFC1122: OK. Passes ICMP errors back to application, as per
391 * 4.1.3.3.
393 if (!inet_sock->recverr) {
394 if (!harderr || sk->sk_state != TCP_ESTABLISHED)
395 goto out;
396 } else {
397 ip_icmp_error(sk, skb, err, 0 /* no remote port */,
398 info, (u8 *)icmph);
400 sk->sk_err = err;
401 sk->sk_error_report(sk);
402 out:
403 sock_put(sk);
407 * Copy and checksum an ICMP Echo packet from user space into a buffer.
410 struct pingfakehdr {
411 struct icmphdr icmph;
412 struct iovec *iov;
413 __wsum wcheck;
416 static int ping_getfrag(void *from, char *to,
417 int offset, int fraglen, int odd, struct sk_buff *skb)
419 struct pingfakehdr *pfh = (struct pingfakehdr *)from;
421 if (offset == 0) {
422 if (fraglen < sizeof(struct icmphdr))
423 BUG();
424 if (csum_partial_copy_fromiovecend(to + sizeof(struct icmphdr),
425 pfh->iov, 0, fraglen - sizeof(struct icmphdr),
426 &pfh->wcheck))
427 return -EFAULT;
429 return 0;
431 if (offset < sizeof(struct icmphdr))
432 BUG();
433 if (csum_partial_copy_fromiovecend
434 (to, pfh->iov, offset - sizeof(struct icmphdr),
435 fraglen, &pfh->wcheck))
436 return -EFAULT;
437 return 0;
440 static int ping_push_pending_frames(struct sock *sk, struct pingfakehdr *pfh,
441 struct flowi4 *fl4)
443 struct sk_buff *skb = skb_peek(&sk->sk_write_queue);
445 pfh->wcheck = csum_partial((char *)&pfh->icmph,
446 sizeof(struct icmphdr), pfh->wcheck);
447 pfh->icmph.checksum = csum_fold(pfh->wcheck);
448 memcpy(icmp_hdr(skb), &pfh->icmph, sizeof(struct icmphdr));
449 skb->ip_summed = CHECKSUM_NONE;
450 return ip_push_pending_frames(sk, fl4);
453 static int ping_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
454 size_t len)
456 struct net *net = sock_net(sk);
457 struct flowi4 fl4;
458 struct inet_sock *inet = inet_sk(sk);
459 struct ipcm_cookie ipc;
460 struct icmphdr user_icmph;
461 struct pingfakehdr pfh;
462 struct rtable *rt = NULL;
463 struct ip_options_data opt_copy;
464 int free = 0;
465 __be32 saddr, daddr, faddr;
466 u8 tos;
467 int err;
469 pr_debug("ping_sendmsg(sk=%p,sk->num=%u)\n", inet, inet->inet_num);
472 if (len > 0xFFFF)
473 return -EMSGSIZE;
476 * Check the flags.
479 /* Mirror BSD error message compatibility */
480 if (msg->msg_flags & MSG_OOB)
481 return -EOPNOTSUPP;
484 * Fetch the ICMP header provided by the userland.
485 * iovec is modified!
488 if (memcpy_fromiovec((u8 *)&user_icmph, msg->msg_iov,
489 sizeof(struct icmphdr)))
490 return -EFAULT;
491 if (!ping_supported(user_icmph.type, user_icmph.code))
492 return -EINVAL;
495 * Get and verify the address.
498 if (msg->msg_name) {
499 struct sockaddr_in *usin = (struct sockaddr_in *)msg->msg_name;
500 if (msg->msg_namelen < sizeof(*usin))
501 return -EINVAL;
502 if (usin->sin_family != AF_INET)
503 return -EINVAL;
504 daddr = usin->sin_addr.s_addr;
505 /* no remote port */
506 } else {
507 if (sk->sk_state != TCP_ESTABLISHED)
508 return -EDESTADDRREQ;
509 daddr = inet->inet_daddr;
510 /* no remote port */
513 ipc.addr = inet->inet_saddr;
514 ipc.opt = NULL;
515 ipc.oif = sk->sk_bound_dev_if;
516 ipc.tx_flags = 0;
517 err = sock_tx_timestamp(sk, &ipc.tx_flags);
518 if (err)
519 return err;
521 if (msg->msg_controllen) {
522 err = ip_cmsg_send(sock_net(sk), msg, &ipc);
523 if (err)
524 return err;
525 if (ipc.opt)
526 free = 1;
528 if (!ipc.opt) {
529 struct ip_options_rcu *inet_opt;
531 rcu_read_lock();
532 inet_opt = rcu_dereference(inet->inet_opt);
533 if (inet_opt) {
534 memcpy(&opt_copy, inet_opt,
535 sizeof(*inet_opt) + inet_opt->opt.optlen);
536 ipc.opt = &opt_copy.opt;
538 rcu_read_unlock();
541 saddr = ipc.addr;
542 ipc.addr = faddr = daddr;
544 if (ipc.opt && ipc.opt->opt.srr) {
545 if (!daddr)
546 return -EINVAL;
547 faddr = ipc.opt->opt.faddr;
549 tos = RT_TOS(inet->tos);
550 if (sock_flag(sk, SOCK_LOCALROUTE) ||
551 (msg->msg_flags & MSG_DONTROUTE) ||
552 (ipc.opt && ipc.opt->opt.is_strictroute)) {
553 tos |= RTO_ONLINK;
556 if (ipv4_is_multicast(daddr)) {
557 if (!ipc.oif)
558 ipc.oif = inet->mc_index;
559 if (!saddr)
560 saddr = inet->mc_addr;
561 } else if (!ipc.oif)
562 ipc.oif = inet->uc_index;
564 flowi4_init_output(&fl4, ipc.oif, sk->sk_mark, tos,
565 RT_SCOPE_UNIVERSE, sk->sk_protocol,
566 inet_sk_flowi_flags(sk), faddr, saddr, 0, 0);
568 security_sk_classify_flow(sk, flowi4_to_flowi(&fl4));
569 rt = ip_route_output_flow(net, &fl4, sk);
570 if (IS_ERR(rt)) {
571 err = PTR_ERR(rt);
572 rt = NULL;
573 if (err == -ENETUNREACH)
574 IP_INC_STATS_BH(net, IPSTATS_MIB_OUTNOROUTES);
575 goto out;
578 err = -EACCES;
579 if ((rt->rt_flags & RTCF_BROADCAST) &&
580 !sock_flag(sk, SOCK_BROADCAST))
581 goto out;
583 if (msg->msg_flags & MSG_CONFIRM)
584 goto do_confirm;
585 back_from_confirm:
587 if (!ipc.addr)
588 ipc.addr = fl4.daddr;
590 lock_sock(sk);
592 pfh.icmph.type = user_icmph.type; /* already checked */
593 pfh.icmph.code = user_icmph.code; /* ditto */
594 pfh.icmph.checksum = 0;
595 pfh.icmph.un.echo.id = inet->inet_sport;
596 pfh.icmph.un.echo.sequence = user_icmph.un.echo.sequence;
597 pfh.iov = msg->msg_iov;
598 pfh.wcheck = 0;
600 err = ip_append_data(sk, &fl4, ping_getfrag, &pfh, len,
601 0, &ipc, &rt, msg->msg_flags);
602 if (err)
603 ip_flush_pending_frames(sk);
604 else
605 err = ping_push_pending_frames(sk, &pfh, &fl4);
606 release_sock(sk);
608 out:
609 ip_rt_put(rt);
610 if (free)
611 kfree(ipc.opt);
612 if (!err) {
613 icmp_out_count(sock_net(sk), user_icmph.type);
614 return len;
616 return err;
618 do_confirm:
619 dst_confirm(&rt->dst);
620 if (!(msg->msg_flags & MSG_PROBE) || len)
621 goto back_from_confirm;
622 err = 0;
623 goto out;
626 static int ping_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
627 size_t len, int noblock, int flags, int *addr_len)
629 struct inet_sock *isk = inet_sk(sk);
630 struct sockaddr_in *sin = (struct sockaddr_in *)msg->msg_name;
631 struct sk_buff *skb;
632 int copied, err;
634 pr_debug("ping_recvmsg(sk=%p,sk->num=%u)\n", isk, isk->inet_num);
636 err = -EOPNOTSUPP;
637 if (flags & MSG_OOB)
638 goto out;
640 if (addr_len)
641 *addr_len = sizeof(*sin);
643 if (flags & MSG_ERRQUEUE)
644 return ip_recv_error(sk, msg, len);
646 skb = skb_recv_datagram(sk, flags, noblock, &err);
647 if (!skb)
648 goto out;
650 copied = skb->len;
651 if (copied > len) {
652 msg->msg_flags |= MSG_TRUNC;
653 copied = len;
656 /* Don't bother checking the checksum */
657 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
658 if (err)
659 goto done;
661 sock_recv_timestamp(msg, sk, skb);
663 /* Copy the address. */
664 if (sin) {
665 sin->sin_family = AF_INET;
666 sin->sin_port = 0 /* skb->h.uh->source */;
667 sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
668 memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
670 if (isk->cmsg_flags)
671 ip_cmsg_recv(msg, skb);
672 err = copied;
674 done:
675 skb_free_datagram(sk, skb);
676 out:
677 pr_debug("ping_recvmsg -> %d\n", err);
678 return err;
681 static int ping_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
683 pr_debug("ping_queue_rcv_skb(sk=%p,sk->num=%d,skb=%p)\n",
684 inet_sk(sk), inet_sk(sk)->inet_num, skb);
685 if (sock_queue_rcv_skb(sk, skb) < 0) {
686 kfree_skb(skb);
687 pr_debug("ping_queue_rcv_skb -> failed\n");
688 return -1;
690 return 0;
695 * All we need to do is get the socket.
698 void ping_rcv(struct sk_buff *skb)
700 struct sock *sk;
701 struct net *net = dev_net(skb->dev);
702 struct iphdr *iph = ip_hdr(skb);
703 struct icmphdr *icmph = icmp_hdr(skb);
704 __be32 saddr = iph->saddr;
705 __be32 daddr = iph->daddr;
707 /* We assume the packet has already been checked by icmp_rcv */
709 pr_debug("ping_rcv(skb=%p,id=%04x,seq=%04x)\n",
710 skb, ntohs(icmph->un.echo.id), ntohs(icmph->un.echo.sequence));
712 /* Push ICMP header back */
713 skb_push(skb, skb->data - (u8 *)icmph);
715 sk = ping_v4_lookup(net, saddr, daddr, ntohs(icmph->un.echo.id),
716 skb->dev->ifindex);
717 if (sk != NULL) {
718 pr_debug("rcv on socket %p\n", sk);
719 ping_queue_rcv_skb(sk, skb_get(skb));
720 sock_put(sk);
721 return;
723 pr_debug("no socket, dropping\n");
725 /* We're called from icmp_rcv(). kfree_skb() is done there. */
728 struct proto ping_prot = {
729 .name = "PING",
730 .owner = THIS_MODULE,
731 .init = ping_init_sock,
732 .close = ping_close,
733 .connect = ip4_datagram_connect,
734 .disconnect = udp_disconnect,
735 .setsockopt = ip_setsockopt,
736 .getsockopt = ip_getsockopt,
737 .sendmsg = ping_sendmsg,
738 .recvmsg = ping_recvmsg,
739 .bind = ping_bind,
740 .backlog_rcv = ping_queue_rcv_skb,
741 .release_cb = ip4_datagram_release_cb,
742 .hash = ping_v4_hash,
743 .unhash = ping_v4_unhash,
744 .get_port = ping_v4_get_port,
745 .obj_size = sizeof(struct inet_sock),
747 EXPORT_SYMBOL(ping_prot);
749 #ifdef CONFIG_PROC_FS
751 static struct sock *ping_get_first(struct seq_file *seq, int start)
753 struct sock *sk;
754 struct ping_iter_state *state = seq->private;
755 struct net *net = seq_file_net(seq);
757 for (state->bucket = start; state->bucket < PING_HTABLE_SIZE;
758 ++state->bucket) {
759 struct hlist_nulls_node *node;
760 struct hlist_nulls_head *hslot;
762 hslot = &ping_table.hash[state->bucket];
764 if (hlist_nulls_empty(hslot))
765 continue;
767 sk_nulls_for_each(sk, node, hslot) {
768 if (net_eq(sock_net(sk), net))
769 goto found;
772 sk = NULL;
773 found:
774 return sk;
777 static struct sock *ping_get_next(struct seq_file *seq, struct sock *sk)
779 struct ping_iter_state *state = seq->private;
780 struct net *net = seq_file_net(seq);
782 do {
783 sk = sk_nulls_next(sk);
784 } while (sk && (!net_eq(sock_net(sk), net)));
786 if (!sk)
787 return ping_get_first(seq, state->bucket + 1);
788 return sk;
791 static struct sock *ping_get_idx(struct seq_file *seq, loff_t pos)
793 struct sock *sk = ping_get_first(seq, 0);
795 if (sk)
796 while (pos && (sk = ping_get_next(seq, sk)) != NULL)
797 --pos;
798 return pos ? NULL : sk;
801 static void *ping_seq_start(struct seq_file *seq, loff_t *pos)
803 struct ping_iter_state *state = seq->private;
804 state->bucket = 0;
806 read_lock_bh(&ping_table.lock);
808 return *pos ? ping_get_idx(seq, *pos-1) : SEQ_START_TOKEN;
811 static void *ping_seq_next(struct seq_file *seq, void *v, loff_t *pos)
813 struct sock *sk;
815 if (v == SEQ_START_TOKEN)
816 sk = ping_get_idx(seq, 0);
817 else
818 sk = ping_get_next(seq, v);
820 ++*pos;
821 return sk;
824 static void ping_seq_stop(struct seq_file *seq, void *v)
826 read_unlock_bh(&ping_table.lock);
829 static void ping_format_sock(struct sock *sp, struct seq_file *f,
830 int bucket, int *len)
832 struct inet_sock *inet = inet_sk(sp);
833 __be32 dest = inet->inet_daddr;
834 __be32 src = inet->inet_rcv_saddr;
835 __u16 destp = ntohs(inet->inet_dport);
836 __u16 srcp = ntohs(inet->inet_sport);
838 seq_printf(f, "%5d: %08X:%04X %08X:%04X"
839 " %02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %pK %d%n",
840 bucket, src, srcp, dest, destp, sp->sk_state,
841 sk_wmem_alloc_get(sp),
842 sk_rmem_alloc_get(sp),
843 0, 0L, 0,
844 from_kuid_munged(seq_user_ns(f), sock_i_uid(sp)),
845 0, sock_i_ino(sp),
846 atomic_read(&sp->sk_refcnt), sp,
847 atomic_read(&sp->sk_drops), len);
850 static int ping_seq_show(struct seq_file *seq, void *v)
852 if (v == SEQ_START_TOKEN)
853 seq_printf(seq, "%-127s\n",
854 " sl local_address rem_address st tx_queue "
855 "rx_queue tr tm->when retrnsmt uid timeout "
856 "inode ref pointer drops");
857 else {
858 struct ping_iter_state *state = seq->private;
859 int len;
861 ping_format_sock(v, seq, state->bucket, &len);
862 seq_printf(seq, "%*s\n", 127 - len, "");
864 return 0;
867 static const struct seq_operations ping_seq_ops = {
868 .show = ping_seq_show,
869 .start = ping_seq_start,
870 .next = ping_seq_next,
871 .stop = ping_seq_stop,
874 static int ping_seq_open(struct inode *inode, struct file *file)
876 return seq_open_net(inode, file, &ping_seq_ops,
877 sizeof(struct ping_iter_state));
880 static const struct file_operations ping_seq_fops = {
881 .open = ping_seq_open,
882 .read = seq_read,
883 .llseek = seq_lseek,
884 .release = seq_release_net,
887 static int ping_proc_register(struct net *net)
889 struct proc_dir_entry *p;
890 int rc = 0;
892 p = proc_net_fops_create(net, "icmp", S_IRUGO, &ping_seq_fops);
893 if (!p)
894 rc = -ENOMEM;
895 return rc;
898 static void ping_proc_unregister(struct net *net)
900 proc_net_remove(net, "icmp");
904 static int __net_init ping_proc_init_net(struct net *net)
906 return ping_proc_register(net);
909 static void __net_exit ping_proc_exit_net(struct net *net)
911 ping_proc_unregister(net);
914 static struct pernet_operations ping_net_ops = {
915 .init = ping_proc_init_net,
916 .exit = ping_proc_exit_net,
919 int __init ping_proc_init(void)
921 return register_pernet_subsys(&ping_net_ops);
924 void ping_proc_exit(void)
926 unregister_pernet_subsys(&ping_net_ops);
929 #endif
931 void __init ping_init(void)
933 int i;
935 for (i = 0; i < PING_HTABLE_SIZE; i++)
936 INIT_HLIST_NULLS_HEAD(&ping_table.hash[i], i);
937 rwlock_init(&ping_table.lock);