3 ICMP Protocol engine - for sending out pings and receiving
7 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
8 * Copyright (c) 1996-2003 by Internet Software Consortium
10 * Permission to use, copy, modify, and distribute this software for any
11 * purpose with or without fee is hereby granted, provided that the above
12 * copyright notice and this permission notice appear in all copies.
14 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
15 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
16 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR
17 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
18 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
19 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
20 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
22 * Internet Systems Consortium, Inc.
24 * Redwood City, CA 94063
28 * This software has been written for Internet Systems Consortium
29 * by Ted Lemon in cooperation with Vixie Enterprises and Nominum, Inc.
30 * To learn more about Internet Systems Consortium, see
31 * ``http://www.isc.org/''. To learn more about Vixie Enterprises,
32 * see ``http://www.vix.com''. To learn more about Nominum, Inc., see
33 * ``http://www.nominum.com''.
37 static char copyright[] =
38 "$Id: icmp.c,v 1.30.2.6 2004/06/10 17:59:18 dhankins Exp $ Copyright (c) 2004 Internet Systems Consortium. All rights reserved.\n";
42 #include "netinet/ip.h"
43 #include "netinet/ip_icmp.h"
45 struct icmp_state *icmp_state;
46 static omapi_object_type_t *dhcp_type_icmp;
49 OMAPI_OBJECT_ALLOC (icmp_state, struct icmp_state, dhcp_type_icmp)
52 trace_type_t *trace_icmp_input;
53 trace_type_t *trace_icmp_output;
56 /* Initialize the ICMP protocol. */
58 void icmp_startup (routep, handler)
60 void (*handler) PROTO ((struct iaddr, u_int8_t *, int));
62 struct protoent *proto;
64 struct sockaddr_in from;
67 struct icmp_state *new;
71 /* Only initialize icmp once. */
73 log_fatal ("attempted to reinitialize icmp protocol");
75 result = omapi_object_type_register (&dhcp_type_icmp, "icmp",
76 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
77 sizeof (struct icmp_state),
80 if (result != ISC_R_SUCCESS)
81 log_fatal ("Can't register icmp object type: %s",
82 isc_result_totext (result));
84 icmp_state_allocate (&icmp_state, MDL);
85 icmp_state -> icmp_handler = handler;
88 trace_icmp_input = trace_type_register ("icmp-input", (void *)0,
89 trace_icmp_input_input,
90 trace_icmp_input_stop, MDL);
91 trace_icmp_output = trace_type_register ("icmp-output", (void *)0,
92 trace_icmp_output_input,
93 trace_icmp_output_stop, MDL);
95 /* If we're playing back a trace file, don't create the socket
96 or set up the callback. */
97 if (!trace_playback ()) {
99 /* Get the protocol number (should be 1). */
100 proto = getprotobyname ("icmp");
102 protocol = proto -> p_proto;
104 /* Get a raw socket for the ICMP protocol. */
105 icmp_state -> socket = socket (AF_INET, SOCK_RAW, protocol);
106 if (icmp_state -> socket < 0) {
108 log_error ("unable to create icmp socket: %m");
112 #if defined (HAVE_SETFD)
113 if (fcntl (icmp_state -> socket, F_SETFD, 1) < 0)
114 log_error ("Can't set close-on-exec on icmp: %m");
117 /* Make sure it does routing... */
119 if (setsockopt (icmp_state -> socket, SOL_SOCKET, SO_DONTROUTE,
120 (char *)&state, sizeof state) < 0)
121 log_fatal ("Can't disable SO_DONTROUTE on ICMP: %m");
123 result = (omapi_register_io_object
124 ((omapi_object_t *)icmp_state,
125 icmp_readsocket, 0, icmp_echoreply, 0, 0));
126 if (result != ISC_R_SUCCESS)
127 log_fatal ("Can't register icmp handle: %s",
128 isc_result_totext (result));
129 #if defined (TRACING)
134 int icmp_readsocket (h)
137 struct icmp_state *state;
139 state = (struct icmp_state *)h;
140 return state -> socket;
143 int icmp_echorequest (addr)
146 struct sockaddr_in to;
149 #if defined (TRACING)
156 log_fatal ("ICMP protocol used before initialization.");
158 memset (&to, 0, sizeof(to));
160 to.sin_len = sizeof to;
162 to.sin_family = AF_INET;
163 to.sin_port = 0; /* unused. */
164 memcpy (&to.sin_addr, addr -> iabuf, sizeof to.sin_addr); /* XXX */
166 icmp.icmp_type = ICMP_ECHO;
171 icmp.icmp_id = (((u_int32_t)(u_int64_t)addr) ^
172 (u_int32_t)(((u_int64_t)addr) >> 32));
174 icmp.icmp_id = (u_int32_t)addr;
176 memset (&icmp.icmp_dun, 0, sizeof icmp.icmp_dun);
178 icmp.icmp_cksum = wrapsum (checksum ((unsigned char *)&icmp,
181 #if defined (TRACING)
182 if (trace_playback ()) {
183 char *buf = (char *)0;
186 /* Consume the ICMP event. */
187 status = trace_get_packet (&trace_icmp_output, &buflen, &buf);
188 if (status != ISC_R_SUCCESS)
189 log_error ("icmp_echorequest: %s",
190 isc_result_totext (status));
194 if (trace_record ()) {
195 iov [0].buf = (char *)addr;
196 iov [0].len = sizeof *addr;
197 iov [1].buf = (char *)&icmp;
198 iov [1].len = sizeof icmp;
199 trace_write_packet_iov (trace_icmp_output,
203 /* Send the ICMP packet... */
204 status = sendto (icmp_state -> socket,
205 (char *)&icmp, sizeof icmp, 0,
206 (struct sockaddr *)&to, sizeof to);
208 log_error ("icmp_echorequest %s: %m",
209 inet_ntoa(to.sin_addr));
211 if (status != sizeof icmp)
213 #if defined (TRACING)
219 isc_result_t icmp_echoreply (h)
224 struct sockaddr_in from;
225 u_int8_t icbuf [1500];
230 struct icmp_state *state;
231 #if defined (TRACING)
235 state = (struct icmp_state *)h;
238 status = recvfrom (state -> socket, (char *)icbuf, sizeof icbuf, 0,
239 (struct sockaddr *)&from, &sl);
241 log_error ("icmp_echoreply: %m");
242 return ISC_R_UNEXPECTED;
245 /* Find the IP header length... */
246 ip = (struct ip *)icbuf;
250 if (status < hlen + (sizeof *icfrom)) {
251 return ISC_R_SUCCESS;
255 icfrom = (struct icmp *)(icbuf + hlen);
257 /* Silently discard ICMP packets that aren't echoreplies. */
258 if (icfrom -> icmp_type != ICMP_ECHOREPLY) {
259 return ISC_R_SUCCESS;
262 /* If we were given a second-stage handler, call it. */
263 if (state -> icmp_handler) {
264 memcpy (ia.iabuf, &from.sin_addr, sizeof from.sin_addr);
265 ia.len = sizeof from.sin_addr;
267 #if defined (TRACING)
268 if (trace_record ()) {
269 ia.len = htonl(ia.len);
270 iov [0].buf = (char *)&ia;
271 iov [0].len = sizeof ia;
272 iov [1].buf = (char *)icbuf;
274 trace_write_packet_iov (trace_icmp_input, 2, iov, MDL);
275 ia.len = ntohl(ia.len);
278 (*state -> icmp_handler) (ia, icbuf, len);
280 return ISC_R_SUCCESS;
283 #if defined (TRACING)
284 void trace_icmp_input_input (trace_type_t *ttype, unsigned length, char *buf)
289 ia = (struct iaddr *)buf;
290 ia->len = ntohl(ia->len);
291 icbuf = (u_int8_t *)(ia + 1);
292 if (icmp_state -> icmp_handler)
293 (*icmp_state -> icmp_handler) (*ia, icbuf,
294 (int)(length - sizeof ia));
297 void trace_icmp_input_stop (trace_type_t *ttype) { }
299 void trace_icmp_output_input (trace_type_t *ttype, unsigned length, char *buf)
304 if (length != (sizeof (*icmp) + (sizeof ia))) {
305 log_error ("trace_icmp_output_input: data size mismatch %d:%d",
306 length, (int)((sizeof (*icmp)) + (sizeof ia)));
310 memcpy (ia.iabuf, buf, 4);
311 icmp = (struct icmp *)(buf + 1);
313 log_error ("trace_icmp_output_input: unsent ping to %s", piaddr (ia));
316 void trace_icmp_output_stop (trace_type_t *ttype) { }