xref: /linux/net/ipv6/ping.c (revision 56d06fa29edd58c448766014afd833b7ff51247b)
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 */
30 static int dummy_ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len,
31 				 int *addr_len)
32 {
33 	return -EAFNOSUPPORT;
34 }
35 static void dummy_ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg,
36 				       struct sk_buff *skb)
37 {
38 }
39 static int dummy_icmpv6_err_convert(u8 type, u8 code, int *err)
40 {
41 	return -EAFNOSUPPORT;
42 }
43 static void dummy_ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
44 				  __be16 port, u32 info, u8 *payload) {}
45 static 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 
51 static 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 
166 struct 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 };
184 EXPORT_SYMBOL_GPL(pingv6_prot);
185 
186 static 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
195 static void *ping_v6_seq_start(struct seq_file *seq, loff_t *pos)
196 {
197 	return ping_seq_start(seq, pos, AF_INET6);
198 }
199 
200 static 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 
214 static 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 
226 static int __net_init ping_v6_proc_init_net(struct net *net)
227 {
228 	return ping_proc_register(net, &ping_v6_seq_afinfo);
229 }
230 
231 static void __net_init ping_v6_proc_exit_net(struct net *net)
232 {
233 	return ping_proc_unregister(net, &ping_v6_seq_afinfo);
234 }
235 
236 static 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 
242 int __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  */
262 void 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 }
275