xref: /linux/net/ipv6/ping.c (revision c0c914eca7f251c70facc37dfebeaf176601918d)
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 struct 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 };
47 EXPORT_SYMBOL_GPL(pingv6_prot);
48 
49 static struct inet_protosw pingv6_protosw = {
50 	.type =      SOCK_DGRAM,
51 	.protocol =  IPPROTO_ICMPV6,
52 	.prot =      &pingv6_prot,
53 	.ops =       &inet6_dgram_ops,
54 	.flags =     INET_PROTOSW_REUSE,
55 };
56 
57 
58 /* Compatibility glue so we can support IPv6 when it's compiled as a module */
59 static int dummy_ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len,
60 				 int *addr_len)
61 {
62 	return -EAFNOSUPPORT;
63 }
64 static void dummy_ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg,
65 				       struct sk_buff *skb)
66 {
67 }
68 static int dummy_icmpv6_err_convert(u8 type, u8 code, int *err)
69 {
70 	return -EAFNOSUPPORT;
71 }
72 static void dummy_ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
73 				  __be16 port, u32 info, u8 *payload) {}
74 static int dummy_ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
75 			       const struct net_device *dev, int strict)
76 {
77 	return 0;
78 }
79 
80 int ping_v6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
81 {
82 	struct inet_sock *inet = inet_sk(sk);
83 	struct ipv6_pinfo *np = inet6_sk(sk);
84 	struct icmp6hdr user_icmph;
85 	int addr_type;
86 	struct in6_addr *daddr;
87 	int iif = 0;
88 	struct flowi6 fl6;
89 	int err;
90 	int hlimit;
91 	struct dst_entry *dst;
92 	struct rt6_info *rt;
93 	struct pingfakehdr pfh;
94 
95 	pr_debug("ping_v6_sendmsg(sk=%p,sk->num=%u)\n", inet, inet->inet_num);
96 
97 	err = ping_common_sendmsg(AF_INET6, msg, len, &user_icmph,
98 				  sizeof(user_icmph));
99 	if (err)
100 		return err;
101 
102 	if (msg->msg_name) {
103 		DECLARE_SOCKADDR(struct sockaddr_in6 *, u, msg->msg_name);
104 		if (msg->msg_namelen < sizeof(*u))
105 			return -EINVAL;
106 		if (u->sin6_family != AF_INET6) {
107 			return -EAFNOSUPPORT;
108 		}
109 		if (sk->sk_bound_dev_if &&
110 		    sk->sk_bound_dev_if != u->sin6_scope_id) {
111 			return -EINVAL;
112 		}
113 		daddr = &(u->sin6_addr);
114 		iif = u->sin6_scope_id;
115 	} else {
116 		if (sk->sk_state != TCP_ESTABLISHED)
117 			return -EDESTADDRREQ;
118 		daddr = &sk->sk_v6_daddr;
119 	}
120 
121 	if (!iif)
122 		iif = sk->sk_bound_dev_if;
123 
124 	addr_type = ipv6_addr_type(daddr);
125 	if (__ipv6_addr_needs_scope_id(addr_type) && !iif)
126 		return -EINVAL;
127 	if (addr_type & IPV6_ADDR_MAPPED)
128 		return -EINVAL;
129 
130 	/* TODO: use ip6_datagram_send_ctl to get options from cmsg */
131 
132 	memset(&fl6, 0, sizeof(fl6));
133 
134 	fl6.flowi6_proto = IPPROTO_ICMPV6;
135 	fl6.saddr = np->saddr;
136 	fl6.daddr = *daddr;
137 	fl6.flowi6_mark = sk->sk_mark;
138 	fl6.fl6_icmp_type = user_icmph.icmp6_type;
139 	fl6.fl6_icmp_code = user_icmph.icmp6_code;
140 	security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
141 
142 	if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
143 		fl6.flowi6_oif = np->mcast_oif;
144 	else if (!fl6.flowi6_oif)
145 		fl6.flowi6_oif = np->ucast_oif;
146 
147 	dst = ip6_sk_dst_lookup_flow(sk, &fl6,  daddr);
148 	if (IS_ERR(dst))
149 		return PTR_ERR(dst);
150 	rt = (struct rt6_info *) dst;
151 
152 	np = inet6_sk(sk);
153 	if (!np)
154 		return -EBADF;
155 
156 	if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
157 		fl6.flowi6_oif = np->mcast_oif;
158 	else if (!fl6.flowi6_oif)
159 		fl6.flowi6_oif = np->ucast_oif;
160 
161 	pfh.icmph.type = user_icmph.icmp6_type;
162 	pfh.icmph.code = user_icmph.icmp6_code;
163 	pfh.icmph.checksum = 0;
164 	pfh.icmph.un.echo.id = inet->inet_sport;
165 	pfh.icmph.un.echo.sequence = user_icmph.icmp6_sequence;
166 	pfh.msg = msg;
167 	pfh.wcheck = 0;
168 	pfh.family = AF_INET6;
169 
170 	hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
171 
172 	lock_sock(sk);
173 	err = ip6_append_data(sk, ping_getfrag, &pfh, len,
174 			      0, hlimit,
175 			      np->tclass, NULL, &fl6, rt,
176 			      MSG_DONTWAIT, np->dontfrag);
177 
178 	if (err) {
179 		ICMP6_INC_STATS(sock_net(sk), rt->rt6i_idev,
180 				ICMP6_MIB_OUTERRORS);
181 		ip6_flush_pending_frames(sk);
182 	} else {
183 		err = icmpv6_push_pending_frames(sk, &fl6,
184 						 (struct icmp6hdr *) &pfh.icmph,
185 						 len);
186 	}
187 	release_sock(sk);
188 
189 	if (err)
190 		return err;
191 
192 	return len;
193 }
194 
195 #ifdef CONFIG_PROC_FS
196 static void *ping_v6_seq_start(struct seq_file *seq, loff_t *pos)
197 {
198 	return ping_seq_start(seq, pos, AF_INET6);
199 }
200 
201 static int ping_v6_seq_show(struct seq_file *seq, void *v)
202 {
203 	if (v == SEQ_START_TOKEN) {
204 		seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
205 	} else {
206 		int bucket = ((struct ping_iter_state *) seq->private)->bucket;
207 		struct inet_sock *inet = inet_sk(v);
208 		__u16 srcp = ntohs(inet->inet_sport);
209 		__u16 destp = ntohs(inet->inet_dport);
210 		ip6_dgram_sock_seq_show(seq, v, srcp, destp, bucket);
211 	}
212 	return 0;
213 }
214 
215 static struct ping_seq_afinfo ping_v6_seq_afinfo = {
216 	.name		= "icmp6",
217 	.family		= AF_INET6,
218 	.seq_fops       = &ping_seq_fops,
219 	.seq_ops	= {
220 		.start		= ping_v6_seq_start,
221 		.show		= ping_v6_seq_show,
222 		.next		= ping_seq_next,
223 		.stop		= ping_seq_stop,
224 	},
225 };
226 
227 static int __net_init ping_v6_proc_init_net(struct net *net)
228 {
229 	return ping_proc_register(net, &ping_v6_seq_afinfo);
230 }
231 
232 static void __net_init ping_v6_proc_exit_net(struct net *net)
233 {
234 	return ping_proc_unregister(net, &ping_v6_seq_afinfo);
235 }
236 
237 static struct pernet_operations ping_v6_net_ops = {
238 	.init = ping_v6_proc_init_net,
239 	.exit = ping_v6_proc_exit_net,
240 };
241 #endif
242 
243 int __init pingv6_init(void)
244 {
245 #ifdef CONFIG_PROC_FS
246 	int ret = register_pernet_subsys(&ping_v6_net_ops);
247 	if (ret)
248 		return ret;
249 #endif
250 	pingv6_ops.ipv6_recv_error = ipv6_recv_error;
251 	pingv6_ops.ip6_datagram_recv_common_ctl = ip6_datagram_recv_common_ctl;
252 	pingv6_ops.ip6_datagram_recv_specific_ctl =
253 		ip6_datagram_recv_specific_ctl;
254 	pingv6_ops.icmpv6_err_convert = icmpv6_err_convert;
255 	pingv6_ops.ipv6_icmp_error = ipv6_icmp_error;
256 	pingv6_ops.ipv6_chk_addr = ipv6_chk_addr;
257 	return inet6_register_protosw(&pingv6_protosw);
258 }
259 
260 /* This never gets called because it's not possible to unload the ipv6 module,
261  * but just in case.
262  */
263 void pingv6_exit(void)
264 {
265 	pingv6_ops.ipv6_recv_error = dummy_ipv6_recv_error;
266 	pingv6_ops.ip6_datagram_recv_common_ctl = dummy_ip6_datagram_recv_ctl;
267 	pingv6_ops.ip6_datagram_recv_specific_ctl = dummy_ip6_datagram_recv_ctl;
268 	pingv6_ops.icmpv6_err_convert = dummy_icmpv6_err_convert;
269 	pingv6_ops.ipv6_icmp_error = dummy_ipv6_icmp_error;
270 	pingv6_ops.ipv6_chk_addr = dummy_ipv6_chk_addr;
271 #ifdef CONFIG_PROC_FS
272 	unregister_pernet_subsys(&ping_v6_net_ops);
273 #endif
274 	inet6_unregister_protosw(&pingv6_protosw);
275 }
276