1 /******************************************************************************/
2 /* */
3 /* Copyright (c) International Business Machines Corp., 2006 */
4 /* */
5 /* This program is free software; you can redistribute it and/or modify */
6 /* it under the terms of the GNU General Public License as published by */
7 /* the Free Software Foundation; either version 2 of the License, or */
8 /* (at your option) any later version. */
9 /* */
10 /* This program is distributed in the hope that it will be useful, */
11 /* but WITHOUT ANY WARRANTY; without even the implied warranty of */
12 /* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See */
13 /* the GNU General Public License for more details. */
14 /* */
15 /* You should have received a copy of the GNU General Public License */
16 /* along with this program; if not, write to the Free Software */
17 /* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */
18 /* */
19 /******************************************************************************/
20
21 /*
22 * File:
23 * ns-igmp_querier.c
24 *
25 * Description:
26 * This utiltity sends IGMP queries.
27 * (General Query, Multicast Address Specific Query
28 * or Multicast Address and Source Specific Query)
29 *
30 * Author:
31 * Mitsuru Chinen <mitch@jp.ibm.com>
32 *
33 * History:
34 * Apr 24 2006 - Created (Mitsuru Chinen)
35 *---------------------------------------------------------------------------*/
36
37 /*
38 * Header Files
39 */
40 #include <stdio.h>
41 #include <stdlib.h>
42 #include <string.h>
43 #include <errno.h>
44 #include <netdb.h>
45 #include <signal.h>
46 #include <time.h>
47 #include <unistd.h>
48 #include <arpa/inet.h>
49 #include <net/if.h>
50 #include <netinet/in.h>
51 #include <netinet/igmp.h>
52 #include <sys/ioctl.h>
53 #include <sys/socket.h>
54 #include <sys/types.h>
55
56 #include "ns-mcast.h"
57 #include "ns-traffic.h"
58
59 /*
60 * Structure Definitions
61 */
62 struct igmp_info {
63 uint32_t ifindex;
64 struct igmpv3_query *query;
65 double timeout;
66 struct timespec interval;
67 };
68
69 /*
70 * Gloval variables
71 */
72 char *program_name; /* program name */
73 struct sigaction handler; /* Behavior for a signal */
74 int catch_sighup; /* When catch the SIGHUP, set to non-zero */
75
76 /*
77 * Function: usage()
78 *
79 * Descripton:
80 * Print the usage of this program. Then, terminate this program with
81 * the specified exit value.
82 *
83 * Argument:
84 * exit_value: exit value
85 *
86 * Return value:
87 * This function does not return.
88 */
usage(char * program_name,int exit_value)89 void usage(char *program_name, int exit_value)
90 {
91 FILE *stream = stdout; /* stream where the usage is output */
92
93 if (exit_value == EXIT_FAILURE)
94 stream = stderr;
95
96 fprintf(stream, "%s [OPTION]\n"
97 "\t-I ifname\tname of listening interface\n"
98 "\t-m addr\tmulticast address\n"
99 "\t-s addrs\tcomma separated array of Source Addresses\n"
100 "\t-r value\tMax Resp Code\n"
101 "\t-i value\tinterval [nanosec]\n"
102 "\t-t value\ttimeout [sec]\n"
103 "\t-o\t\tsend only one query\n"
104 "\t-b\t\twork in the background\n"
105 "\t-d\t\tdisplay debug informations\n"
106 "\t-h\t\tdisplay this usage\n", program_name);
107 exit(exit_value);
108 }
109
110 /*
111 * Function: set_signal_flag()
112 *
113 * Description:
114 * This function sets global variables accordig to signal
115 *
116 * Argument:
117 * type: type of signal
118 *
119 * Return value:
120 * None
121 */
set_signal_flag(int type)122 void set_signal_flag(int type)
123 {
124 if (debug)
125 fprintf(stderr, "Catch signal. type is %d\n", type);
126
127 switch (type) {
128 case SIGHUP:
129 catch_sighup = 1;
130 handler.sa_handler = SIG_IGN;
131 if (sigaction(type, &handler, NULL) < 0)
132 fatal_error("sigaction()");
133 break;
134
135 default:
136 fprintf(stderr, "Unexpected signal (%d) is caught\n", type);
137 exit(EXIT_FAILURE);
138 }
139 }
140
141 /*
142 * Function: create_query()
143 *
144 * Description:
145 * This function create a igmpv3 query information.
146 * This function allocates memory to store the information.
147 *
148 * Argument:
149 * code: Max Resp Code
150 * maddr: multicast address
151 * saddrs: comma separated array of the source addresses
152 *
153 * Return value:
154 * pointer to allocated igmpv3_query structure
155 */
create_query(uint8_t code,char * maddr,char * saddrs)156 struct igmpv3_query *create_query(uint8_t code, char *maddr, char *saddrs)
157 {
158 struct igmpv3_query *query; /* pointer to igmpv3_query structure */
159 uint16_t numsrc; /* number of source address */
160 size_t query_size; /* size of igmpv3_query */
161 struct in_addr ip;
162 uint32_t idx;
163 char *sp, *ep;
164
165 /* calculate the number of source address */
166 if (saddrs == NULL) {
167 numsrc = 0;
168 } else {
169 numsrc = 1;
170 for (sp = saddrs; *sp != '\0'; sp++)
171 if (*sp == ',')
172 numsrc++;
173 }
174 if (debug)
175 fprintf(stderr, "number of source address is %u\n", numsrc);
176
177 /* allocate memory for igmpv3_query structure */
178 query_size = MY_IGMPV3_QUERY_SIZE(numsrc);
179 query = (struct igmpv3_query *)calloc(1, query_size);
180 if (query == NULL)
181 fatal_error("calloc()");
182
183 /* substitute paramaters */
184 query->type = IGMP_HOST_MEMBERSHIP_QUERY;
185 query->code = code;
186 query->csum = 0; /* Calculate later */
187 query->resv = 0;
188 query->suppress = 0;
189 query->qrv = 0;
190 query->qqic = 0;
191 query->nsrcs = htons(numsrc);
192
193 /* substitute multicast address */
194 if (maddr == NULL) {
195 query->group = htonl(INADDR_ANY);
196 } else {
197 if (inet_pton(AF_INET, maddr, &ip) <= 0) {
198 fprintf(stderr,
199 "multicast address is something wrong\n");
200 return NULL;
201 }
202 query->group = ip.s_addr;
203 }
204
205 /* substitute source addresses */
206 sp = saddrs;
207 for (idx = 0; idx < numsrc; idx++) {
208 ep = strchr(sp, ',');
209 if (ep != NULL)
210 *ep = '\0';
211 if (debug)
212 fprintf(stderr, "source address[%u]: %s\n", idx, sp);
213
214 if (inet_pton(AF_INET, sp, &ip) <= 0) {
215 fprintf(stderr,
216 "source address list is something wrong\n");
217 return NULL;
218 }
219 query->srcs[idx] = ip.s_addr;
220 sp = ep + 1;
221 }
222
223 /* Calculate checksum */
224 query->csum = calc_checksum((u_int16_t *) query, query_size);
225
226 return query;
227 }
228
229 /*
230 * Function: parse_options()
231 *
232 * Description:
233 * This function parse the options
234 *
235 * Argument:
236 * argc: the number of argument
237 * argv: arguments
238 * info_p: pointer to data of querier information
239 * bg_p: pointer to the flag of working in backgrond
240 *
241 * Return value:
242 * None
243 */
parse_options(int argc,char * argv[],struct igmp_info * info_p,int * bg_p)244 void parse_options(int argc, char *argv[], struct igmp_info *info_p, int *bg_p)
245 {
246 int optc; /* option */
247 unsigned long opt_ul; /* option value in unsigned long */
248 double opt_d; /* option value in double */
249 uint8_t max_resp; /* Max Resp Code */
250 char *maddr; /* multicast address */
251 char *saddrs; /* comma separated array of source addresses */
252
253 max_resp = IGMP_MAX_HOST_REPORT_DELAY;
254 maddr = NULL;
255 saddrs = NULL;
256
257 while ((optc = getopt(argc, argv, "I:m:s:r:t:i:obdh")) != EOF) {
258 switch (optc) {
259 case 'I':
260 info_p->ifindex = if_nametoindex(optarg);
261 if (info_p->ifindex == 0) {
262 fprintf(stderr,
263 "specified interface is incorrect\n");
264 usage(program_name, EXIT_FAILURE);
265 }
266 break;
267
268 case 'm':
269 maddr = strdup(optarg);
270 if (maddr == NULL)
271 fatal_error("strdup()");
272 break;
273
274 case 's':
275 saddrs = strdup(optarg);
276 if (saddrs == NULL)
277 fatal_error("strdup()");
278 break;
279
280 case 'r':
281 opt_ul = strtoul(optarg, NULL, 0);
282 if (opt_ul > 255) {
283 fprintf(stderr,
284 "Max Resp Code should be less then 256\n");
285 usage(program_name, EXIT_FAILURE);
286 }
287 max_resp = opt_ul;
288 break;
289
290 case 't':
291 opt_d = strtod(optarg, NULL);
292 if (opt_d < 0.0) {
293 fprintf(stderr,
294 "Timeout should be positive value\n");
295 usage(program_name, EXIT_FAILURE);
296 }
297 info_p->timeout = opt_d;
298 break;
299
300 case 'i':
301 if (strtotimespec(optarg, &info_p->interval)) {
302 fprintf(stderr,
303 "Interval is something wrong\n");
304 usage(program_name, EXIT_FAILURE);
305 }
306 break;
307
308 case 'o':
309 info_p->timeout = -1.0;
310 break;
311
312 case 'b':
313 *bg_p = 1;
314 break;
315
316 case 'd':
317 debug = 1;
318 break;
319
320 case 'h':
321 usage(program_name, EXIT_SUCCESS);
322 break;
323
324 default:
325 usage(program_name, EXIT_FAILURE);
326 }
327 }
328
329 if (info_p->ifindex == 0) {
330 fprintf(stderr, "specified interface seems incorrect\n");
331 usage(program_name, EXIT_FAILURE);
332 }
333
334 if ((info_p->query = create_query(max_resp, maddr, saddrs)) == NULL)
335 usage(program_name, EXIT_FAILURE);
336
337 free(maddr);
338 free(saddrs);
339 }
340
341 /*
342 * Function: create_socket()
343 *
344 * Description:
345 * This function creates a socket to send
346 *
347 * Argument:
348 * info_p: pointer to data of igmp query information
349 *
350 * Return value:
351 * file descriptor referencing the socket
352 */
create_socket(struct igmp_info * info_p)353 int create_socket(struct igmp_info *info_p)
354 {
355 int sd; /* socket file descriptor */
356 int on;
357 unsigned char opt[4] = { 0x94, 0x04, 0x00, 0x00 }; /* Router Alert */
358 struct ip_mreqn mcast_req, *req_p = &mcast_req;
359
360 /* Create a socket */
361 sd = socket(AF_INET, SOCK_RAW, IPPROTO_IGMP);
362 if (sd < 0)
363 fatal_error("socket()");
364
365 /* Enable to reuse the socket */
366 on = 1;
367 if (setsockopt(sd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(int)))
368 fatal_error("setsockopt(): enable to reuse the socket");
369
370 /* Add router alert option */
371 if (setsockopt(sd, IPPROTO_IP, IP_OPTIONS, opt, sizeof(opt)))
372 fatal_error("setsockopt(): socket options");
373
374 /* Specify the interface for outgoing datagrams */
375 req_p->imr_multiaddr.s_addr = info_p->query->group;
376 req_p->imr_address.s_addr = htonl(INADDR_ANY);
377 req_p->imr_ifindex = info_p->ifindex;
378 if (setsockopt(sd, IPPROTO_IP, IP_MULTICAST_IF,
379 req_p, sizeof(struct ip_mreqn))) {
380 fatal_error("setsockopt(): specify the interface");
381 }
382
383 return sd;
384 }
385
386 /*
387 * Function: send_query()
388 *
389 * Description:
390 * This function sends IGMP query
391 *
392 * Argument:
393 * info_p: pointer to data of igmp query information
394 *
395 * Return value:
396 * None
397 */
send_query(struct igmp_info * info_p)398 void send_query(struct igmp_info *info_p)
399 {
400 int sd;
401 int retval;
402 double start_time;
403 struct sockaddr_in to;
404 size_t query_size;
405
406 /* Set singal hander for SIGHUP */
407 handler.sa_handler = set_signal_flag;
408 handler.sa_flags = 0;
409 if (sigfillset(&handler.sa_mask) < 0)
410 fatal_error("sigfillset()");
411 if (sigaction(SIGHUP, &handler, NULL) < 0)
412 fatal_error("sigaction()");
413
414 /* Specify multicast address to send */
415 to.sin_family = AF_INET;
416 to.sin_port = IPPROTO_IGMP;
417 if (info_p->query->group == htonl(INADDR_ANY))
418 to.sin_addr.s_addr = IGMP_ALL_HOSTS;
419 else
420 to.sin_addr.s_addr = info_p->query->group;
421
422 /* Create a socket */
423 sd = create_socket(info_p);
424
425 /* loop for sending queries */
426 start_time = time(NULL);
427 query_size = MY_IGMPV3_QUERY_SIZE(ntohs(info_p->query->nsrcs));
428 if (debug)
429 fprintf(stderr, "query size is %zu\n", query_size);
430
431 for (;;) {
432 retval = sendto(sd, info_p->query, query_size, 0,
433 (struct sockaddr *)&to,
434 sizeof(struct sockaddr_in));
435 if (retval != query_size) {
436 if (errno == ENOBUFS) {
437 sleep(1);
438 continue;
439 }
440
441 if (catch_sighup)
442 break;
443 else
444 fatal_error("sendto()");
445 }
446
447 /* Check timeout:
448 If timeout value is negative only send one datagram */
449 if (info_p->timeout)
450 if (info_p->timeout < difftime(time(NULL), start_time))
451 break;
452
453 /* Wait in specified interval */
454 nanosleep(&info_p->interval, NULL);
455
456 /* catch SIGHUP */
457 if (catch_sighup)
458 break;
459
460 }
461
462 close(sd);
463 }
464
465 /*
466 *
467 * Function: main()
468 *
469 */
main(int argc,char * argv[])470 int main(int argc, char *argv[])
471 {
472 struct igmp_info mcast_rcv;
473 int background = 0;
474
475 debug = 0;
476 program_name = strdup(argv[0]);
477
478 memset(&mcast_rcv, '\0', sizeof(struct igmp_info));
479 parse_options(argc, argv, &mcast_rcv, &background);
480
481 if (background) /* Work in the background */
482 if (daemon(0, 0) < 0)
483 fatal_error("daemon()");
484
485 send_query(&mcast_rcv);
486
487 exit(EXIT_SUCCESS);
488 }
489