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.
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 <asm/system.h>
24 #include <linux/uaccess.h>
25 #include <linux/types.h>
26 #include <linux/fcntl.h>
27 #include <linux/socket.h>
28 #include <linux/sockios.h>
30 #include <linux/errno.h>
31 #include <linux/timer.h>
33 #include <linux/inet.h>
34 #include <linux/netdevice.h>
39 #include <net/protocol.h>
40 #include <linux/skbuff.h>
41 #include <linux/proc_fs.h>
42 #include <linux/export.h>
46 #include <net/route.h>
47 #include <net/inet_common.h>
48 #include <net/checksum.h>
51 static struct ping_table ping_table;
53 static u16 ping_port_rover;
55 static inline int ping_hashfn(struct net *net, unsigned num, unsigned mask)
57 int res = (num + net_hash_mix(net)) & mask;
58 pr_debug("hash(%d) = %d\n", num, res);
62 static inline struct hlist_nulls_head *ping_hashslot(struct ping_table *table,
63 struct net *net, unsigned 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;
76 write_lock_bh(&ping_table.lock);
79 u16 result = ping_port_rover + 1;
81 for (i = 0; i < (1L << 16); i++, result++) {
83 result++; /* avoid zero */
84 hlist = ping_hashslot(&ping_table, sock_net(sk),
86 ping_portaddr_for_each_entry(sk2, node, hlist) {
89 if (isk2->inet_num == result)
94 ping_port_rover = ident = result;
102 hlist = ping_hashslot(&ping_table, sock_net(sk), ident);
103 ping_portaddr_for_each_entry(sk2, node, hlist) {
106 if ((isk2->inet_num == ident) &&
108 (!sk2->sk_reuse || !sk->sk_reuse))
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");
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);
125 write_unlock_bh(&ping_table.lock);
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);
140 write_lock_bh(&ping_table.lock);
141 hlist_nulls_del(&sk->sk_nulls_node);
142 sk_nulls_node_init(&sk->sk_nulls_node);
144 isk->inet_num = 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, u32 saddr, u32 daddr,
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 = %ld, dif = %d\n",
159 (int)ident, (unsigned long)daddr, dif);
160 read_lock_bh(&ping_table.lock);
162 ping_portaddr_for_each_entry(sk, hnode, hslot) {
165 pr_debug("found: %p: num = %d, daddr = %ld, dif = %d\n", sk,
166 (int)isk->inet_num, (unsigned long)isk->inet_rcv_saddr,
167 sk->sk_bound_dev_if);
169 pr_debug("iterate\n");
170 if (isk->inet_num != ident)
172 if (isk->inet_rcv_saddr && isk->inet_rcv_saddr != daddr)
174 if (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif)
183 read_unlock_bh(&ping_table.lock);
188 static void inet_get_ping_group_range_net(struct net *net, gid_t *low,
191 gid_t *data = net->ipv4.sysctl_ping_group_range;
194 seq = read_seqbegin(&sysctl_local_ports.lock);
198 } while (read_seqretry(&sysctl_local_ports.lock, seq));
202 static int ping_init_sock(struct sock *sk)
204 struct net *net = sock_net(sk);
205 gid_t group = current_egid();
207 struct group_info *group_info;
211 inet_get_ping_group_range_net(net, range, range+1);
212 if (range[0] <= group && group <= range[1])
215 group_info = get_current_groups();
216 count = group_info->ngroups;
217 for (i = 0; i < group_info->nblocks; i++) {
218 int cp_count = min_t(int, NGROUPS_PER_BLOCK, count);
220 for (j = 0; j < cp_count; j++) {
221 group = group_info->blocks[i][j];
222 if (range[0] <= group && group <= range[1])
223 goto out_release_group;
232 put_group_info(group_info);
236 static void ping_close(struct sock *sk, long timeout)
238 pr_debug("ping_close(sk=%p,sk->num=%u)\n",
239 inet_sk(sk), inet_sk(sk)->inet_num);
240 pr_debug("isk->refcnt = %d\n", sk->sk_refcnt.counter);
242 sk_common_release(sk);
246 * We need our own bind because there are no privileged id's == local ports.
247 * Moreover, we don't allow binding to multi- and broadcast addresses.
250 static int ping_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len)
252 struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
253 struct inet_sock *isk = inet_sk(sk);
258 if (addr_len < sizeof(struct sockaddr_in))
261 if (addr->sin_family != AF_INET &&
262 !(addr->sin_family == AF_UNSPEC &&
263 addr->sin_addr.s_addr == htonl(INADDR_ANY)))
264 return -EAFNOSUPPORT;
266 pr_debug("ping_v4_bind(sk=%p,sa_addr=%08x,sa_port=%d)\n",
267 sk, addr->sin_addr.s_addr, ntohs(addr->sin_port));
269 chk_addr_ret = inet_addr_type(sock_net(sk), addr->sin_addr.s_addr);
270 if (addr->sin_addr.s_addr == INADDR_ANY)
271 chk_addr_ret = RTN_LOCAL;
273 if ((sysctl_ip_nonlocal_bind == 0 &&
274 isk->freebind == 0 && isk->transparent == 0 &&
275 chk_addr_ret != RTN_LOCAL) ||
276 chk_addr_ret == RTN_MULTICAST ||
277 chk_addr_ret == RTN_BROADCAST)
278 return -EADDRNOTAVAIL;
283 if (isk->inet_num != 0)
287 isk->inet_rcv_saddr = isk->inet_saddr = addr->sin_addr.s_addr;
288 snum = ntohs(addr->sin_port);
289 if (ping_v4_get_port(sk, snum) != 0) {
290 isk->inet_saddr = isk->inet_rcv_saddr = 0;
294 pr_debug("after bind(): num = %d, daddr = %ld, dif = %d\n",
296 (unsigned long) isk->inet_rcv_saddr,
297 (int)sk->sk_bound_dev_if);
300 if (isk->inet_rcv_saddr)
301 sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
303 sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
304 isk->inet_sport = htons(isk->inet_num);
310 pr_debug("ping_v4_bind -> %d\n", err);
315 * Is this a supported type of ICMP message?
318 static inline int ping_supported(int type, int code)
320 if (type == ICMP_ECHO && code == 0)
326 * This routine is called by the ICMP module when it gets some
327 * sort of error condition.
330 static int ping_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
332 void ping_err(struct sk_buff *skb, u32 info)
334 struct iphdr *iph = (struct iphdr *)skb->data;
335 struct icmphdr *icmph = (struct icmphdr *)(skb->data+(iph->ihl<<2));
336 struct inet_sock *inet_sock;
337 int type = icmp_hdr(skb)->type;
338 int code = icmp_hdr(skb)->code;
339 struct net *net = dev_net(skb->dev);
344 /* We assume the packet has already been checked by icmp_unreach */
346 if (!ping_supported(icmph->type, icmph->code))
349 pr_debug("ping_err(type=%04x,code=%04x,id=%04x,seq=%04x)\n", type,
350 code, ntohs(icmph->un.echo.id), ntohs(icmph->un.echo.sequence));
352 sk = ping_v4_lookup(net, iph->daddr, iph->saddr,
353 ntohs(icmph->un.echo.id), skb->dev->ifindex);
355 pr_debug("no socket, dropping\n");
356 return; /* No socket for error */
358 pr_debug("err on socket %p\n", sk);
362 inet_sock = inet_sk(sk);
366 case ICMP_TIME_EXCEEDED:
369 case ICMP_SOURCE_QUENCH:
370 /* This is not a real error but ping wants to see it.
371 * Report it with some fake errno. */
374 case ICMP_PARAMETERPROB:
378 case ICMP_DEST_UNREACH:
379 if (code == ICMP_FRAG_NEEDED) { /* Path MTU discovery */
380 if (inet_sock->pmtudisc != IP_PMTUDISC_DONT) {
388 if (code <= NR_ICMP_UNREACH) {
389 harderr = icmp_err_convert[code].fatal;
390 err = icmp_err_convert[code].errno;
394 /* See ICMP_SOURCE_QUENCH */
400 * RFC1122: OK. Passes ICMP errors back to application, as per
403 if (!inet_sock->recverr) {
404 if (!harderr || sk->sk_state != TCP_ESTABLISHED)
407 ip_icmp_error(sk, skb, err, 0 /* no remote port */,
411 sk->sk_error_report(sk);
417 * Copy and checksum an ICMP Echo packet from user space into a buffer.
421 struct icmphdr icmph;
426 static int ping_getfrag(void *from, char * to,
427 int offset, int fraglen, int odd, struct sk_buff *skb)
429 struct pingfakehdr *pfh = (struct pingfakehdr *)from;
432 if (fraglen < sizeof(struct icmphdr))
434 if (csum_partial_copy_fromiovecend(to + sizeof(struct icmphdr),
435 pfh->iov, 0, fraglen - sizeof(struct icmphdr),
441 if (offset < sizeof(struct icmphdr))
443 if (csum_partial_copy_fromiovecend
444 (to, pfh->iov, offset - sizeof(struct icmphdr),
445 fraglen, &pfh->wcheck))
450 static int ping_push_pending_frames(struct sock *sk, struct pingfakehdr *pfh,
453 struct sk_buff *skb = skb_peek(&sk->sk_write_queue);
455 pfh->wcheck = csum_partial((char *)&pfh->icmph,
456 sizeof(struct icmphdr), pfh->wcheck);
457 pfh->icmph.checksum = csum_fold(pfh->wcheck);
458 memcpy(icmp_hdr(skb), &pfh->icmph, sizeof(struct icmphdr));
459 skb->ip_summed = CHECKSUM_NONE;
460 return ip_push_pending_frames(sk, fl4);
463 static int ping_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
466 struct net *net = sock_net(sk);
468 struct inet_sock *inet = inet_sk(sk);
469 struct ipcm_cookie ipc;
470 struct icmphdr user_icmph;
471 struct pingfakehdr pfh;
472 struct rtable *rt = NULL;
473 struct ip_options_data opt_copy;
475 u32 saddr, daddr, faddr;
479 pr_debug("ping_sendmsg(sk=%p,sk->num=%u)\n", inet, inet->inet_num);
489 /* Mirror BSD error message compatibility */
490 if (msg->msg_flags & MSG_OOB)
494 * Fetch the ICMP header provided by the userland.
498 if (memcpy_fromiovec((u8 *)&user_icmph, msg->msg_iov,
499 sizeof(struct icmphdr)))
501 if (!ping_supported(user_icmph.type, user_icmph.code))
505 * Get and verify the address.
509 struct sockaddr_in *usin = (struct sockaddr_in *)msg->msg_name;
510 if (msg->msg_namelen < sizeof(*usin))
512 if (usin->sin_family != AF_INET)
513 return -EAFNOSUPPORT;
514 daddr = usin->sin_addr.s_addr;
517 if (sk->sk_state != TCP_ESTABLISHED)
518 return -EDESTADDRREQ;
519 daddr = inet->inet_daddr;
523 ipc.addr = inet->inet_saddr;
525 ipc.oif = sk->sk_bound_dev_if;
527 err = sock_tx_timestamp(sk, &ipc.tx_flags);
531 if (msg->msg_controllen) {
532 err = ip_cmsg_send(sock_net(sk), msg, &ipc);
539 struct ip_options_rcu *inet_opt;
542 inet_opt = rcu_dereference(inet->inet_opt);
544 memcpy(&opt_copy, inet_opt,
545 sizeof(*inet_opt) + inet_opt->opt.optlen);
546 ipc.opt = &opt_copy.opt;
552 ipc.addr = faddr = daddr;
554 if (ipc.opt && ipc.opt->opt.srr) {
557 faddr = ipc.opt->opt.faddr;
559 tos = RT_TOS(inet->tos);
560 if (sock_flag(sk, SOCK_LOCALROUTE) ||
561 (msg->msg_flags & MSG_DONTROUTE) ||
562 (ipc.opt && ipc.opt->opt.is_strictroute)) {
566 if (ipv4_is_multicast(daddr)) {
568 ipc.oif = inet->mc_index;
570 saddr = inet->mc_addr;
573 flowi4_init_output(&fl4, ipc.oif, sk->sk_mark, tos,
574 RT_SCOPE_UNIVERSE, sk->sk_protocol,
575 inet_sk_flowi_flags(sk), faddr, saddr, 0, 0);
577 security_sk_classify_flow(sk, flowi4_to_flowi(&fl4));
578 rt = ip_route_output_flow(net, &fl4, sk);
582 if (err == -ENETUNREACH)
583 IP_INC_STATS(net, IPSTATS_MIB_OUTNOROUTES);
588 if ((rt->rt_flags & RTCF_BROADCAST) &&
589 !sock_flag(sk, SOCK_BROADCAST))
592 if (msg->msg_flags & MSG_CONFIRM)
597 ipc.addr = fl4.daddr;
601 pfh.icmph.type = user_icmph.type; /* already checked */
602 pfh.icmph.code = user_icmph.code; /* ditto */
603 pfh.icmph.checksum = 0;
604 pfh.icmph.un.echo.id = inet->inet_sport;
605 pfh.icmph.un.echo.sequence = user_icmph.un.echo.sequence;
606 pfh.iov = msg->msg_iov;
609 err = ip_append_data(sk, &fl4, ping_getfrag, &pfh, len,
610 0, &ipc, &rt, msg->msg_flags);
612 ip_flush_pending_frames(sk);
614 err = ping_push_pending_frames(sk, &pfh, &fl4);
622 icmp_out_count(sock_net(sk), user_icmph.type);
628 dst_confirm(&rt->dst);
629 if (!(msg->msg_flags & MSG_PROBE) || len)
630 goto back_from_confirm;
635 static int ping_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
636 size_t len, int noblock, int flags, int *addr_len)
638 struct inet_sock *isk = inet_sk(sk);
642 pr_debug("ping_recvmsg(sk=%p,sk->num=%u)\n", isk, isk->inet_num);
647 if (flags & MSG_ERRQUEUE)
648 return ip_recv_error(sk, msg, len, addr_len);
650 skb = skb_recv_datagram(sk, flags, noblock, &err);
656 msg->msg_flags |= MSG_TRUNC;
660 /* Don't bother checking the checksum */
661 err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
665 sock_recv_timestamp(msg, sk, skb);
667 /* Copy the address. */
669 struct sockaddr_in *sin = (struct sockaddr_in *)msg->msg_name;
671 sin->sin_family = AF_INET;
672 sin->sin_port = 0 /* skb->h.uh->source */;
673 sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
674 memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
675 *addr_len = sizeof(*sin);
678 ip_cmsg_recv(msg, skb);
682 skb_free_datagram(sk, skb);
684 pr_debug("ping_recvmsg -> %d\n", err);
688 static int ping_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
690 pr_debug("ping_queue_rcv_skb(sk=%p,sk->num=%d,skb=%p)\n",
691 inet_sk(sk), inet_sk(sk)->inet_num, skb);
692 if (sock_queue_rcv_skb(sk, skb) < 0) {
694 pr_debug("ping_queue_rcv_skb -> failed\n");
702 * All we need to do is get the socket.
705 void ping_rcv(struct sk_buff *skb)
708 struct net *net = dev_net(skb->dev);
709 struct iphdr *iph = ip_hdr(skb);
710 struct icmphdr *icmph = icmp_hdr(skb);
711 u32 saddr = iph->saddr;
712 u32 daddr = iph->daddr;
714 /* We assume the packet has already been checked by icmp_rcv */
716 pr_debug("ping_rcv(skb=%p,id=%04x,seq=%04x)\n",
717 skb, ntohs(icmph->un.echo.id), ntohs(icmph->un.echo.sequence));
719 /* Push ICMP header back */
720 skb_push(skb, skb->data - (u8 *)icmph);
722 sk = ping_v4_lookup(net, saddr, daddr, ntohs(icmph->un.echo.id),
725 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
727 pr_debug("rcv on socket %p\n", sk);
729 ping_queue_rcv_skb(sk, skb2);
733 pr_debug("no socket, dropping\n");
735 /* We're called from icmp_rcv(). kfree_skb() is done there. */
738 struct proto ping_prot = {
740 .owner = THIS_MODULE,
741 .init = ping_init_sock,
743 .connect = ip4_datagram_connect,
744 .disconnect = udp_disconnect,
745 .setsockopt = ip_setsockopt,
746 .getsockopt = ip_getsockopt,
747 .sendmsg = ping_sendmsg,
748 .recvmsg = ping_recvmsg,
750 .backlog_rcv = ping_queue_rcv_skb,
751 .hash = ping_v4_hash,
752 .unhash = ping_v4_unhash,
753 .get_port = ping_v4_get_port,
754 .obj_size = sizeof(struct inet_sock),
756 EXPORT_SYMBOL(ping_prot);
758 #ifdef CONFIG_PROC_FS
760 static struct sock *ping_get_first(struct seq_file *seq, int start)
763 struct ping_iter_state *state = seq->private;
764 struct net *net = seq_file_net(seq);
766 for (state->bucket = start; state->bucket < PING_HTABLE_SIZE;
768 struct hlist_nulls_node *node;
769 struct hlist_nulls_head *hslot;
771 hslot = &ping_table.hash[state->bucket];
773 if (hlist_nulls_empty(hslot))
776 sk_nulls_for_each(sk, node, hslot) {
777 if (net_eq(sock_net(sk), net))
786 static struct sock *ping_get_next(struct seq_file *seq, struct sock *sk)
788 struct ping_iter_state *state = seq->private;
789 struct net *net = seq_file_net(seq);
792 sk = sk_nulls_next(sk);
793 } while (sk && (!net_eq(sock_net(sk), net)));
796 return ping_get_first(seq, state->bucket + 1);
800 static struct sock *ping_get_idx(struct seq_file *seq, loff_t pos)
802 struct sock *sk = ping_get_first(seq, 0);
805 while (pos && (sk = ping_get_next(seq, sk)) != NULL)
807 return pos ? NULL : sk;
810 static void *ping_seq_start(struct seq_file *seq, loff_t *pos)
812 struct ping_iter_state *state = seq->private;
815 read_lock_bh(&ping_table.lock);
817 return *pos ? ping_get_idx(seq, *pos-1) : SEQ_START_TOKEN;
820 static void *ping_seq_next(struct seq_file *seq, void *v, loff_t *pos)
824 if (v == SEQ_START_TOKEN)
825 sk = ping_get_idx(seq, 0);
827 sk = ping_get_next(seq, v);
833 static void ping_seq_stop(struct seq_file *seq, void *v)
835 read_unlock_bh(&ping_table.lock);
838 static void ping_format_sock(struct sock *sp, struct seq_file *f,
839 int bucket, int *len)
841 struct inet_sock *inet = inet_sk(sp);
842 __be32 dest = inet->inet_daddr;
843 __be32 src = inet->inet_rcv_saddr;
844 __u16 destp = ntohs(inet->inet_dport);
845 __u16 srcp = ntohs(inet->inet_sport);
847 seq_printf(f, "%5d: %08X:%04X %08X:%04X"
848 " %02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %pK %d%n",
849 bucket, src, srcp, dest, destp, sp->sk_state,
850 sk_wmem_alloc_get(sp),
851 sk_rmem_alloc_get(sp),
852 0, 0L, 0, sock_i_uid(sp), 0, sock_i_ino(sp),
853 atomic_read(&sp->sk_refcnt), sp,
854 atomic_read(&sp->sk_drops), len);
857 static int ping_seq_show(struct seq_file *seq, void *v)
859 if (v == SEQ_START_TOKEN)
860 seq_printf(seq, "%-127s\n",
861 " sl local_address rem_address st tx_queue "
862 "rx_queue tr tm->when retrnsmt uid timeout "
863 "inode ref pointer drops");
865 struct ping_iter_state *state = seq->private;
868 ping_format_sock(v, seq, state->bucket, &len);
869 seq_printf(seq, "%*s\n", 127 - len, "");
874 static const struct seq_operations ping_seq_ops = {
875 .show = ping_seq_show,
876 .start = ping_seq_start,
877 .next = ping_seq_next,
878 .stop = ping_seq_stop,
881 static int ping_seq_open(struct inode *inode, struct file *file)
883 return seq_open_net(inode, file, &ping_seq_ops,
884 sizeof(struct ping_iter_state));
887 static const struct file_operations ping_seq_fops = {
888 .open = ping_seq_open,
891 .release = seq_release_net,
894 static int ping_proc_register(struct net *net)
896 struct proc_dir_entry *p;
899 p = proc_net_fops_create(net, "icmp", S_IRUGO, &ping_seq_fops);
905 static void ping_proc_unregister(struct net *net)
907 proc_net_remove(net, "icmp");
911 static int __net_init ping_proc_init_net(struct net *net)
913 return ping_proc_register(net);
916 static void __net_exit ping_proc_exit_net(struct net *net)
918 ping_proc_unregister(net);
921 static struct pernet_operations ping_net_ops = {
922 .init = ping_proc_init_net,
923 .exit = ping_proc_exit_net,
926 int __init ping_proc_init(void)
928 return register_pernet_subsys(&ping_net_ops);
931 void ping_proc_exit(void)
933 unregister_pernet_subsys(&ping_net_ops);
938 void __init ping_init(void)
942 for (i = 0; i < PING_HTABLE_SIZE; i++)
943 INIT_HLIST_NULLS_HEAD(&ping_table.hash[i], i);
944 rwlock_init(&ping_table.lock);