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/ping.c code.
 14 *
 15 * Authors:	Lorenzo Colitti (IPv6 support)
 16 *		Vasiliy Kulikov / Openwall (IPv4 implementation, for Linux 2.6),
 17 *		Pavel Kankovsky (IPv4 implementation, for Linux 2.4.32)
 18 *
 19 */
 20
 21#include <net/addrconf.h>
 22#include <net/ipv6.h>
 23#include <net/ip6_route.h>
 24#include <net/protocol.h>
 25#include <net/udp.h>
 26#include <net/transp_v6.h>
 27#include <net/ping.h>
 28
 29/* Compatibility glue so we can support IPv6 when it's compiled as a module */
 30static int dummy_ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len,
 31				 int *addr_len)
 32{
 33	return -EAFNOSUPPORT;
 34}
 35static void dummy_ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg,
 36				       struct sk_buff *skb)
 37{
 38}
 39static int dummy_icmpv6_err_convert(u8 type, u8 code, int *err)
 40{
 41	return -EAFNOSUPPORT;
 42}
 43static void dummy_ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
 44				  __be16 port, u32 info, u8 *payload) {}
 45static int dummy_ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
 46			       const struct net_device *dev, int strict)
 47{
 48	return 0;
 49}
 50
 51static int ping_v6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
 52{
 53	struct inet_sock *inet = inet_sk(sk);
 54	struct ipv6_pinfo *np = inet6_sk(sk);
 55	struct icmp6hdr user_icmph;
 56	int addr_type;
 57	struct in6_addr *daddr;
 58	int iif = 0;
 59	struct flowi6 fl6;
 60	int err;
 61	int hlimit;
 62	struct dst_entry *dst;
 63	struct rt6_info *rt;
 64	struct pingfakehdr pfh;
 65
 66	pr_debug("ping_v6_sendmsg(sk=%p,sk->num=%u)\n", inet, inet->inet_num);
 67
 68	err = ping_common_sendmsg(AF_INET6, msg, len, &user_icmph,
 69				  sizeof(user_icmph));
 70	if (err)
 71		return err;
 72
 73	if (msg->msg_name) {
 74		DECLARE_SOCKADDR(struct sockaddr_in6 *, u, msg->msg_name);
 75		if (msg->msg_namelen < sizeof(*u))
 76			return -EINVAL;
 77		if (u->sin6_family != AF_INET6) {
 78			return -EAFNOSUPPORT;
 79		}
 80		if (sk->sk_bound_dev_if &&
 81		    sk->sk_bound_dev_if != u->sin6_scope_id) {
 82			return -EINVAL;
 83		}
 84		daddr = &(u->sin6_addr);
 85		iif = u->sin6_scope_id;
 86	} else {
 87		if (sk->sk_state != TCP_ESTABLISHED)
 88			return -EDESTADDRREQ;
 89		daddr = &sk->sk_v6_daddr;
 90	}
 91
 92	if (!iif)
 93		iif = sk->sk_bound_dev_if;
 94
 95	addr_type = ipv6_addr_type(daddr);
 96	if (__ipv6_addr_needs_scope_id(addr_type) && !iif)
 97		return -EINVAL;
 98	if (addr_type & IPV6_ADDR_MAPPED)
 99		return -EINVAL;
100
101	/* TODO: use ip6_datagram_send_ctl to get options from cmsg */
102
103	memset(&fl6, 0, sizeof(fl6));
104
105	fl6.flowi6_proto = IPPROTO_ICMPV6;
106	fl6.saddr = np->saddr;
107	fl6.daddr = *daddr;
108	fl6.flowi6_mark = sk->sk_mark;
109	fl6.fl6_icmp_type = user_icmph.icmp6_type;
110	fl6.fl6_icmp_code = user_icmph.icmp6_code;
111	security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
112
113	if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
114		fl6.flowi6_oif = np->mcast_oif;
115	else if (!fl6.flowi6_oif)
116		fl6.flowi6_oif = np->ucast_oif;
117
118	dst = ip6_sk_dst_lookup_flow(sk, &fl6,  daddr);
119	if (IS_ERR(dst))
120		return PTR_ERR(dst);
121	rt = (struct rt6_info *) dst;
122
123	np = inet6_sk(sk);
124	if (!np)
125		return -EBADF;
126
127	if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
128		fl6.flowi6_oif = np->mcast_oif;
129	else if (!fl6.flowi6_oif)
130		fl6.flowi6_oif = np->ucast_oif;
131
132	pfh.icmph.type = user_icmph.icmp6_type;
133	pfh.icmph.code = user_icmph.icmp6_code;
134	pfh.icmph.checksum = 0;
135	pfh.icmph.un.echo.id = inet->inet_sport;
136	pfh.icmph.un.echo.sequence = user_icmph.icmp6_sequence;
137	pfh.msg = msg;
138	pfh.wcheck = 0;
139	pfh.family = AF_INET6;
140
141	hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
142
143	lock_sock(sk);
144	err = ip6_append_data(sk, ping_getfrag, &pfh, len,
145			      0, hlimit,
146			      np->tclass, NULL, &fl6, rt,
147			      MSG_DONTWAIT, np->dontfrag);
148
149	if (err) {
150		ICMP6_INC_STATS(sock_net(sk), rt->rt6i_idev,
151				ICMP6_MIB_OUTERRORS);
152		ip6_flush_pending_frames(sk);
153	} else {
154		err = icmpv6_push_pending_frames(sk, &fl6,
155						 (struct icmp6hdr *) &pfh.icmph,
156						 len);
157	}
158	release_sock(sk);
159
160	if (err)
161		return err;
162
163	return len;
164}
165
166struct proto pingv6_prot = {
167	.name =		"PINGv6",
168	.owner =	THIS_MODULE,
169	.init =		ping_init_sock,
170	.close =	ping_close,
171	.connect =	ip6_datagram_connect_v6_only,
172	.disconnect =	udp_disconnect,
173	.setsockopt =	ipv6_setsockopt,
174	.getsockopt =	ipv6_getsockopt,
175	.sendmsg =	ping_v6_sendmsg,
176	.recvmsg =	ping_recvmsg,
177	.bind =		ping_bind,
178	.backlog_rcv =	ping_queue_rcv_skb,
179	.hash =		ping_hash,
180	.unhash =	ping_unhash,
181	.get_port =	ping_get_port,
182	.obj_size =	sizeof(struct raw6_sock),
183};
184EXPORT_SYMBOL_GPL(pingv6_prot);
185
186static struct inet_protosw pingv6_protosw = {
187	.type =      SOCK_DGRAM,
188	.protocol =  IPPROTO_ICMPV6,
189	.prot =      &pingv6_prot,
190	.ops =       &inet6_dgram_ops,
191	.flags =     INET_PROTOSW_REUSE,
192};
193
194#ifdef CONFIG_PROC_FS
195static void *ping_v6_seq_start(struct seq_file *seq, loff_t *pos)
196{
197	return ping_seq_start(seq, pos, AF_INET6);
198}
199
200static int ping_v6_seq_show(struct seq_file *seq, void *v)
201{
202	if (v == SEQ_START_TOKEN) {
203		seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
204	} else {
205		int bucket = ((struct ping_iter_state *) seq->private)->bucket;
206		struct inet_sock *inet = inet_sk(v);
207		__u16 srcp = ntohs(inet->inet_sport);
208		__u16 destp = ntohs(inet->inet_dport);
209		ip6_dgram_sock_seq_show(seq, v, srcp, destp, bucket);
210	}
211	return 0;
212}
213
214static struct ping_seq_afinfo ping_v6_seq_afinfo = {
215	.name		= "icmp6",
216	.family		= AF_INET6,
217	.seq_fops       = &ping_seq_fops,
218	.seq_ops	= {
219		.start		= ping_v6_seq_start,
220		.show		= ping_v6_seq_show,
221		.next		= ping_seq_next,
222		.stop		= ping_seq_stop,
223	},
224};
225
226static int __net_init ping_v6_proc_init_net(struct net *net)
227{
228	return ping_proc_register(net, &ping_v6_seq_afinfo);
229}
230
231static void __net_init ping_v6_proc_exit_net(struct net *net)
232{
233	return ping_proc_unregister(net, &ping_v6_seq_afinfo);
234}
235
236static struct pernet_operations ping_v6_net_ops = {
237	.init = ping_v6_proc_init_net,
238	.exit = ping_v6_proc_exit_net,
239};
240#endif
241
242int __init pingv6_init(void)
243{
244#ifdef CONFIG_PROC_FS
245	int ret = register_pernet_subsys(&ping_v6_net_ops);
246	if (ret)
247		return ret;
248#endif
249	pingv6_ops.ipv6_recv_error = ipv6_recv_error;
250	pingv6_ops.ip6_datagram_recv_common_ctl = ip6_datagram_recv_common_ctl;
251	pingv6_ops.ip6_datagram_recv_specific_ctl =
252		ip6_datagram_recv_specific_ctl;
253	pingv6_ops.icmpv6_err_convert = icmpv6_err_convert;
254	pingv6_ops.ipv6_icmp_error = ipv6_icmp_error;
255	pingv6_ops.ipv6_chk_addr = ipv6_chk_addr;
256	return inet6_register_protosw(&pingv6_protosw);
257}
258
259/* This never gets called because it's not possible to unload the ipv6 module,
260 * but just in case.
261 */
262void pingv6_exit(void)
263{
264	pingv6_ops.ipv6_recv_error = dummy_ipv6_recv_error;
265	pingv6_ops.ip6_datagram_recv_common_ctl = dummy_ip6_datagram_recv_ctl;
266	pingv6_ops.ip6_datagram_recv_specific_ctl = dummy_ip6_datagram_recv_ctl;
267	pingv6_ops.icmpv6_err_convert = dummy_icmpv6_err_convert;
268	pingv6_ops.ipv6_icmp_error = dummy_ipv6_icmp_error;
269	pingv6_ops.ipv6_chk_addr = dummy_ipv6_chk_addr;
270#ifdef CONFIG_PROC_FS
271	unregister_pernet_subsys(&ping_v6_net_ops);
272#endif
273	inet6_unregister_protosw(&pingv6_protosw);
274}