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
 29struct proto pingv6_prot = {
 30	.name =		"PINGv6",
 31	.owner =	THIS_MODULE,
 32	.init =		ping_init_sock,
 33	.close =	ping_close,
 34	.connect =	ip6_datagram_connect_v6_only,
 35	.disconnect =	udp_disconnect,
 36	.setsockopt =	ipv6_setsockopt,
 37	.getsockopt =	ipv6_getsockopt,
 38	.sendmsg =	ping_v6_sendmsg,
 39	.recvmsg =	ping_recvmsg,
 40	.bind =		ping_bind,
 41	.backlog_rcv =	ping_queue_rcv_skb,
 42	.hash =		ping_hash,
 43	.unhash =	ping_unhash,
 44	.get_port =	ping_get_port,
 45	.obj_size =	sizeof(struct raw6_sock),
 46};
 47EXPORT_SYMBOL_GPL(pingv6_prot);
 48
 49static struct inet_protosw pingv6_protosw = {
 50	.type =      SOCK_DGRAM,
 51	.protocol =  IPPROTO_ICMPV6,
 52	.prot =      &pingv6_prot,
 53	.ops =       &inet6_dgram_ops,
 54	.no_check =  UDP_CSUM_DEFAULT,
 55	.flags =     INET_PROTOSW_REUSE,
 56};
 57
 58
 59/* Compatibility glue so we can support IPv6 when it's compiled as a module */
 60static int dummy_ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len,
 61				 int *addr_len)
 62{
 63	return -EAFNOSUPPORT;
 64}
 65static void dummy_ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg,
 66				       struct sk_buff *skb)
 67{
 68}
 69static int dummy_icmpv6_err_convert(u8 type, u8 code, int *err)
 70{
 71	return -EAFNOSUPPORT;
 72}
 73static void dummy_ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
 74				  __be16 port, u32 info, u8 *payload) {}
 75static int dummy_ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
 76			       const struct net_device *dev, int strict)
 77{
 78	return 0;
 79}
 80
 81int ping_v6_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 82		    size_t len)
 83{
 84	struct inet_sock *inet = inet_sk(sk);
 85	struct ipv6_pinfo *np = inet6_sk(sk);
 86	struct icmp6hdr user_icmph;
 87	int addr_type;
 88	struct in6_addr *daddr;
 89	int iif = 0;
 90	struct flowi6 fl6;
 91	int err;
 92	int hlimit;
 93	struct dst_entry *dst;
 94	struct rt6_info *rt;
 95	struct pingfakehdr pfh;
 96
 97	pr_debug("ping_v6_sendmsg(sk=%p,sk->num=%u)\n", inet, inet->inet_num);
 98
 99	err = ping_common_sendmsg(AF_INET6, msg, len, &user_icmph,
100				  sizeof(user_icmph));
101	if (err)
102		return err;
103
104	if (msg->msg_name) {
105		DECLARE_SOCKADDR(struct sockaddr_in6 *, u, msg->msg_name);
106		if (msg->msg_namelen < sizeof(struct sockaddr_in6) ||
107		    u->sin6_family != AF_INET6) {
108			return -EINVAL;
109		}
110		if (sk->sk_bound_dev_if &&
111		    sk->sk_bound_dev_if != u->sin6_scope_id) {
112			return -EINVAL;
113		}
114		daddr = &(u->sin6_addr);
115		iif = u->sin6_scope_id;
116	} else {
117		if (sk->sk_state != TCP_ESTABLISHED)
118			return -EDESTADDRREQ;
119		daddr = &sk->sk_v6_daddr;
120	}
121
122	if (!iif)
123		iif = sk->sk_bound_dev_if;
124
125	addr_type = ipv6_addr_type(daddr);
126	if (__ipv6_addr_needs_scope_id(addr_type) && !iif)
127		return -EINVAL;
128	if (addr_type & IPV6_ADDR_MAPPED)
129		return -EINVAL;
130
131	/* TODO: use ip6_datagram_send_ctl to get options from cmsg */
132
133	memset(&fl6, 0, sizeof(fl6));
134
135	fl6.flowi6_proto = IPPROTO_ICMPV6;
136	fl6.saddr = np->saddr;
137	fl6.daddr = *daddr;
138	fl6.flowi6_mark = sk->sk_mark;
139	fl6.fl6_icmp_type = user_icmph.icmp6_type;
140	fl6.fl6_icmp_code = user_icmph.icmp6_code;
141	security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
142
143	if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
144		fl6.flowi6_oif = np->mcast_oif;
145	else if (!fl6.flowi6_oif)
146		fl6.flowi6_oif = np->ucast_oif;
147
148	dst = ip6_sk_dst_lookup_flow(sk, &fl6,  daddr);
149	if (IS_ERR(dst))
150		return PTR_ERR(dst);
151	rt = (struct rt6_info *) dst;
152
153	np = inet6_sk(sk);
154	if (!np)
155		return -EBADF;
156
157	if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
158		fl6.flowi6_oif = np->mcast_oif;
159	else if (!fl6.flowi6_oif)
160		fl6.flowi6_oif = np->ucast_oif;
161
162	pfh.icmph.type = user_icmph.icmp6_type;
163	pfh.icmph.code = user_icmph.icmp6_code;
164	pfh.icmph.checksum = 0;
165	pfh.icmph.un.echo.id = inet->inet_sport;
166	pfh.icmph.un.echo.sequence = user_icmph.icmp6_sequence;
167	pfh.iov = msg->msg_iov;
168	pfh.wcheck = 0;
169	pfh.family = AF_INET6;
170
171	if (ipv6_addr_is_multicast(&fl6.daddr))
172		hlimit = np->mcast_hops;
173	else
174		hlimit = np->hop_limit;
175	if (hlimit < 0)
176		hlimit = ip6_dst_hoplimit(dst);
177
178	lock_sock(sk);
179	err = ip6_append_data(sk, ping_getfrag, &pfh, len,
180			      0, hlimit,
181			      np->tclass, NULL, &fl6, rt,
182			      MSG_DONTWAIT, np->dontfrag);
183
184	if (err) {
185		ICMP6_INC_STATS(sock_net(sk), rt->rt6i_idev,
186				ICMP6_MIB_OUTERRORS);
187		ip6_flush_pending_frames(sk);
188	} else {
189		err = icmpv6_push_pending_frames(sk, &fl6,
190						 (struct icmp6hdr *) &pfh.icmph,
191						 len);
192	}
193	release_sock(sk);
194
195	if (err)
196		return err;
197
198	return len;
199}
200
201#ifdef CONFIG_PROC_FS
202static void *ping_v6_seq_start(struct seq_file *seq, loff_t *pos)
203{
204	return ping_seq_start(seq, pos, AF_INET6);
205}
206
207static int ping_v6_seq_show(struct seq_file *seq, void *v)
208{
209	if (v == SEQ_START_TOKEN) {
210		seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
211	} else {
212		int bucket = ((struct ping_iter_state *) seq->private)->bucket;
213		struct inet_sock *inet = inet_sk(v);
214		__u16 srcp = ntohs(inet->inet_sport);
215		__u16 destp = ntohs(inet->inet_dport);
216		ip6_dgram_sock_seq_show(seq, v, srcp, destp, bucket);
217	}
218	return 0;
219}
220
221static struct ping_seq_afinfo ping_v6_seq_afinfo = {
222	.name		= "icmp6",
223	.family		= AF_INET6,
224	.seq_fops       = &ping_seq_fops,
225	.seq_ops	= {
226		.start		= ping_v6_seq_start,
227		.show		= ping_v6_seq_show,
228		.next		= ping_seq_next,
229		.stop		= ping_seq_stop,
230	},
231};
232
233static int __net_init ping_v6_proc_init_net(struct net *net)
234{
235	return ping_proc_register(net, &ping_v6_seq_afinfo);
236}
237
238static void __net_init ping_v6_proc_exit_net(struct net *net)
239{
240	return ping_proc_unregister(net, &ping_v6_seq_afinfo);
241}
242
243static struct pernet_operations ping_v6_net_ops = {
244	.init = ping_v6_proc_init_net,
245	.exit = ping_v6_proc_exit_net,
246};
247#endif
248
249int __init pingv6_init(void)
250{
251#ifdef CONFIG_PROC_FS
252	int ret = register_pernet_subsys(&ping_v6_net_ops);
253	if (ret)
254		return ret;
255#endif
256	pingv6_ops.ipv6_recv_error = ipv6_recv_error;
257	pingv6_ops.ip6_datagram_recv_common_ctl = ip6_datagram_recv_common_ctl;
258	pingv6_ops.ip6_datagram_recv_specific_ctl =
259		ip6_datagram_recv_specific_ctl;
260	pingv6_ops.icmpv6_err_convert = icmpv6_err_convert;
261	pingv6_ops.ipv6_icmp_error = ipv6_icmp_error;
262	pingv6_ops.ipv6_chk_addr = ipv6_chk_addr;
263	return inet6_register_protosw(&pingv6_protosw);
264}
265
266/* This never gets called because it's not possible to unload the ipv6 module,
267 * but just in case.
268 */
269void pingv6_exit(void)
270{
271	pingv6_ops.ipv6_recv_error = dummy_ipv6_recv_error;
272	pingv6_ops.ip6_datagram_recv_common_ctl = dummy_ip6_datagram_recv_ctl;
273	pingv6_ops.ip6_datagram_recv_specific_ctl = dummy_ip6_datagram_recv_ctl;
274	pingv6_ops.icmpv6_err_convert = dummy_icmpv6_err_convert;
275	pingv6_ops.ipv6_icmp_error = dummy_ipv6_icmp_error;
276	pingv6_ops.ipv6_chk_addr = dummy_ipv6_chk_addr;
277#ifdef CONFIG_PROC_FS
278	unregister_pernet_subsys(&ping_v6_net_ops);
279#endif
280	inet6_unregister_protosw(&pingv6_protosw);
281}