xref: /linux/net/ipv6/ping.c (revision e0bf6c5ca2d3281f231c5f0c9bf145e9513644de)
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 kiocb *iocb, struct sock *sk, struct msghdr *msg,
81 		    size_t len)
82 {
83 	struct inet_sock *inet = inet_sk(sk);
84 	struct ipv6_pinfo *np = inet6_sk(sk);
85 	struct icmp6hdr user_icmph;
86 	int addr_type;
87 	struct in6_addr *daddr;
88 	int iif = 0;
89 	struct flowi6 fl6;
90 	int err;
91 	int hlimit;
92 	struct dst_entry *dst;
93 	struct rt6_info *rt;
94 	struct pingfakehdr pfh;
95 
96 	pr_debug("ping_v6_sendmsg(sk=%p,sk->num=%u)\n", inet, inet->inet_num);
97 
98 	err = ping_common_sendmsg(AF_INET6, msg, len, &user_icmph,
99 				  sizeof(user_icmph));
100 	if (err)
101 		return err;
102 
103 	if (msg->msg_name) {
104 		DECLARE_SOCKADDR(struct sockaddr_in6 *, u, msg->msg_name);
105 		if (msg->msg_namelen < sizeof(*u))
106 			return -EINVAL;
107 		if (u->sin6_family != AF_INET6) {
108 			return -EAFNOSUPPORT;
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.msg = msg;
168 	pfh.wcheck = 0;
169 	pfh.family = AF_INET6;
170 
171 	hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
172 
173 	lock_sock(sk);
174 	err = ip6_append_data(sk, ping_getfrag, &pfh, len,
175 			      0, hlimit,
176 			      np->tclass, NULL, &fl6, rt,
177 			      MSG_DONTWAIT, np->dontfrag);
178 
179 	if (err) {
180 		ICMP6_INC_STATS(sock_net(sk), rt->rt6i_idev,
181 				ICMP6_MIB_OUTERRORS);
182 		ip6_flush_pending_frames(sk);
183 	} else {
184 		err = icmpv6_push_pending_frames(sk, &fl6,
185 						 (struct icmp6hdr *) &pfh.icmph,
186 						 len);
187 	}
188 	release_sock(sk);
189 
190 	if (err)
191 		return err;
192 
193 	return len;
194 }
195 
196 #ifdef CONFIG_PROC_FS
197 static void *ping_v6_seq_start(struct seq_file *seq, loff_t *pos)
198 {
199 	return ping_seq_start(seq, pos, AF_INET6);
200 }
201 
202 static int ping_v6_seq_show(struct seq_file *seq, void *v)
203 {
204 	if (v == SEQ_START_TOKEN) {
205 		seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
206 	} else {
207 		int bucket = ((struct ping_iter_state *) seq->private)->bucket;
208 		struct inet_sock *inet = inet_sk(v);
209 		__u16 srcp = ntohs(inet->inet_sport);
210 		__u16 destp = ntohs(inet->inet_dport);
211 		ip6_dgram_sock_seq_show(seq, v, srcp, destp, bucket);
212 	}
213 	return 0;
214 }
215 
216 static struct ping_seq_afinfo ping_v6_seq_afinfo = {
217 	.name		= "icmp6",
218 	.family		= AF_INET6,
219 	.seq_fops       = &ping_seq_fops,
220 	.seq_ops	= {
221 		.start		= ping_v6_seq_start,
222 		.show		= ping_v6_seq_show,
223 		.next		= ping_seq_next,
224 		.stop		= ping_seq_stop,
225 	},
226 };
227 
228 static int __net_init ping_v6_proc_init_net(struct net *net)
229 {
230 	return ping_proc_register(net, &ping_v6_seq_afinfo);
231 }
232 
233 static void __net_init ping_v6_proc_exit_net(struct net *net)
234 {
235 	return ping_proc_unregister(net, &ping_v6_seq_afinfo);
236 }
237 
238 static struct pernet_operations ping_v6_net_ops = {
239 	.init = ping_v6_proc_init_net,
240 	.exit = ping_v6_proc_exit_net,
241 };
242 #endif
243 
244 int __init pingv6_init(void)
245 {
246 #ifdef CONFIG_PROC_FS
247 	int ret = register_pernet_subsys(&ping_v6_net_ops);
248 	if (ret)
249 		return ret;
250 #endif
251 	pingv6_ops.ipv6_recv_error = ipv6_recv_error;
252 	pingv6_ops.ip6_datagram_recv_common_ctl = ip6_datagram_recv_common_ctl;
253 	pingv6_ops.ip6_datagram_recv_specific_ctl =
254 		ip6_datagram_recv_specific_ctl;
255 	pingv6_ops.icmpv6_err_convert = icmpv6_err_convert;
256 	pingv6_ops.ipv6_icmp_error = ipv6_icmp_error;
257 	pingv6_ops.ipv6_chk_addr = ipv6_chk_addr;
258 	return inet6_register_protosw(&pingv6_protosw);
259 }
260 
261 /* This never gets called because it's not possible to unload the ipv6 module,
262  * but just in case.
263  */
264 void pingv6_exit(void)
265 {
266 	pingv6_ops.ipv6_recv_error = dummy_ipv6_recv_error;
267 	pingv6_ops.ip6_datagram_recv_common_ctl = dummy_ip6_datagram_recv_ctl;
268 	pingv6_ops.ip6_datagram_recv_specific_ctl = dummy_ip6_datagram_recv_ctl;
269 	pingv6_ops.icmpv6_err_convert = dummy_icmpv6_err_convert;
270 	pingv6_ops.ipv6_icmp_error = dummy_ipv6_icmp_error;
271 	pingv6_ops.ipv6_chk_addr = dummy_ipv6_chk_addr;
272 #ifdef CONFIG_PROC_FS
273 	unregister_pernet_subsys(&ping_v6_net_ops);
274 #endif
275 	inet6_unregister_protosw(&pingv6_protosw);
276 }
277