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authorMike Frysinger <vapier@gentoo.org>2006-04-27 02:03:03 +0000
committerMike Frysinger <vapier@gentoo.org>2006-04-27 02:03:03 +0000
commitee3e57db0d309247a3a6160f1d32e74ef9e15fec (patch)
tree41e83634364c95fc24fe94096792fcaead242f1c
parent2f5f59189ee80bd70426902e10bbea517a8e7f8b (diff)
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Giuseppe Ciotta writes: add -t, --retries=NUM to show_usage()
Diffstat
-rw-r--r--networking/udhcp/dhcpc.c573
1 files changed, 573 insertions, 0 deletions
diff --git a/networking/udhcp/dhcpc.c b/networking/udhcp/dhcpc.c
new file mode 100644
index 000000000..7878e8eea
--- /dev/null
+++ b/networking/udhcp/dhcpc.c
@@ -0,0 +1,573 @@
1/* dhcpc.c
2 *
3 * udhcp DHCP client
4 *
5 * Russ Dill <Russ.Dill@asu.edu> July 2001
6 *
7 * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
8 */
9
10#include <sys/time.h>
11#include <sys/file.h>
12#include <unistd.h>
13#include <getopt.h>
14#include <stdlib.h>
15#include <sys/socket.h>
16#include <netinet/in.h>
17#include <arpa/inet.h>
18#include <signal.h>
19#include <time.h>
20#include <string.h>
21#include <sys/ioctl.h>
22#include <net/if.h>
23#include <errno.h>
24
25#include "common.h"
26#include "dhcpd.h"
27#include "dhcpc.h"
28#include "options.h"
29#include "clientpacket.h"
30#include "clientsocket.h"
31#include "script.h"
32#include "socket.h"
33#include "signalpipe.h"
34
35static int state;
36static unsigned long requested_ip; /* = 0 */
37static unsigned long server_addr;
38static unsigned long timeout;
39static int packet_num; /* = 0 */
40static int fd = -1;
41
42#define LISTEN_NONE 0
43#define LISTEN_KERNEL 1
44#define LISTEN_RAW 2
45static int listen_mode;
46
47struct client_config_t client_config = {
48 /* Default options. */
49 .abort_if_no_lease = 0,
50 .foreground = 0,
51 .quit_after_lease = 0,
52 .background_if_no_lease = 0,
53 .interface = "eth0",
54 .pidfile = NULL,
55 .script = DEFAULT_SCRIPT,
56 .clientid = NULL,
57 .vendorclass = NULL,
58 .hostname = NULL,
59 .fqdn = NULL,
60 .ifindex = 0,
61 .retries = 3,
62 .timeout = 3,
63 .arp = "\0\0\0\0\0\0", /* appease gcc-3.0 */
64};
65
66#ifndef IN_BUSYBOX
67static void ATTRIBUTE_NORETURN show_usage(void)
68{
69 printf(
70"Usage: udhcpc [OPTIONS]\n\n"
71" -c, --clientid=CLIENTID Set client identifier - type is first char\n"
72" -C, --clientid-none Suppress default client identifier\n"
73" -V, --vendorclass=CLASSID Set vendor class identifier\n"
74" -H, --hostname=HOSTNAME Client hostname\n"
75" -h Alias for -H\n"
76" -F, --fqdn=FQDN Client fully qualified domain name\n"
77" -f, --foreground Do not fork after getting lease\n"
78" -b, --background Fork to background if lease cannot be\n"
79" immediately negotiated.\n"
80" -i, --interface=INTERFACE Interface to use (default: eth0)\n"
81" -n, --now Exit with failure if lease cannot be\n"
82" immediately negotiated.\n"
83" -p, --pidfile=file Store process ID of daemon in file\n"
84" -q, --quit Quit after obtaining lease\n"
85" -r, --request=IP IP address to request (default: none)\n"
86" -s, --script=file Run file at dhcp events (default:\n"
87" " DEFAULT_SCRIPT ")\n"
88" -T, --timeout=seconds Try to get the lease for the amount of\n"
89" seconds (default: 3)\n"
90" -t, --retries=NUM Send up to NUM request packets\n"
91" -v, --version Display version\n"
92 );
93 exit(0);
94}
95#else
96#define show_usage bb_show_usage
97extern void show_usage(void) ATTRIBUTE_NORETURN;
98#endif
99
100
101/* just a little helper */
102static void change_mode(int new_mode)
103{
104 DEBUG(LOG_INFO, "entering %s listen mode",
105 new_mode ? (new_mode == 1 ? "kernel" : "raw") : "none");
106 if (fd >= 0) close(fd);
107 fd = -1;
108 listen_mode = new_mode;
109}
110
111
112/* perform a renew */
113static void perform_renew(void)
114{
115 LOG(LOG_INFO, "Performing a DHCP renew");
116 switch (state) {
117 case BOUND:
118 change_mode(LISTEN_KERNEL);
119 case RENEWING:
120 case REBINDING:
121 state = RENEW_REQUESTED;
122 break;
123 case RENEW_REQUESTED: /* impatient are we? fine, square 1 */
124 run_script(NULL, "deconfig");
125 case REQUESTING:
126 case RELEASED:
127 change_mode(LISTEN_RAW);
128 state = INIT_SELECTING;
129 break;
130 case INIT_SELECTING:
131 break;
132 }
133
134 /* start things over */
135 packet_num = 0;
136
137 /* Kill any timeouts because the user wants this to hurry along */
138 timeout = 0;
139}
140
141
142/* perform a release */
143static void perform_release(void)
144{
145 char buffer[16];
146 struct in_addr temp_addr;
147
148 /* send release packet */
149 if (state == BOUND || state == RENEWING || state == REBINDING) {
150 temp_addr.s_addr = server_addr;
151 sprintf(buffer, "%s", inet_ntoa(temp_addr));
152 temp_addr.s_addr = requested_ip;
153 LOG(LOG_INFO, "Unicasting a release of %s to %s",
154 inet_ntoa(temp_addr), buffer);
155 send_release(server_addr, requested_ip); /* unicast */
156 run_script(NULL, "deconfig");
157 }
158 LOG(LOG_INFO, "Entering released state");
159
160 change_mode(LISTEN_NONE);
161 state = RELEASED;
162 timeout = 0x7fffffff;
163}
164
165
166static void client_background(void)
167{
168 background(client_config.pidfile);
169 client_config.foreground = 1; /* Do not fork again. */
170 client_config.background_if_no_lease = 0;
171}
172
173
174#ifdef COMBINED_BINARY
175int udhcpc_main(int argc, char *argv[])
176#else
177int main(int argc, char *argv[])
178#endif
179{
180 uint8_t *temp, *message;
181 unsigned long t1 = 0, t2 = 0, xid = 0;
182 unsigned long start = 0, lease;
183 fd_set rfds;
184 int retval;
185 struct timeval tv;
186 int c, len;
187 struct dhcpMessage packet;
188 struct in_addr temp_addr;
189 long now;
190 int max_fd;
191 int sig;
192 int no_clientid = 0;
193
194 static const struct option arg_options[] = {
195 {"clientid", required_argument, 0, 'c'},
196 {"clientid-none", no_argument, 0, 'C'},
197 {"vendorclass", required_argument, 0, 'V'},
198 {"foreground", no_argument, 0, 'f'},
199 {"background", no_argument, 0, 'b'},
200 {"hostname", required_argument, 0, 'H'},
201 {"hostname", required_argument, 0, 'h'},
202 {"fqdn", required_argument, 0, 'F'},
203 {"interface", required_argument, 0, 'i'},
204 {"now", no_argument, 0, 'n'},
205 {"pidfile", required_argument, 0, 'p'},
206 {"quit", no_argument, 0, 'q'},
207 {"request", required_argument, 0, 'r'},
208 {"script", required_argument, 0, 's'},
209 {"timeout", required_argument, 0, 'T'},
210 {"version", no_argument, 0, 'v'},
211 {"retries", required_argument, 0, 't'},
212 {0, 0, 0, 0}
213 };
214
215 /* get options */
216 while (1) {
217 int option_index = 0;
218 c = getopt_long(argc, argv, "c:CV:fbH:h:F:i:np:qr:s:T:t:v", arg_options, &option_index);
219 if (c == -1) break;
220
221 switch (c) {
222 case 'c':
223 if (no_clientid) show_usage();
224 len = strlen(optarg) > 255 ? 255 : strlen(optarg);
225 free(client_config.clientid);
226 client_config.clientid = xmalloc(len + 2);
227 client_config.clientid[OPT_CODE] = DHCP_CLIENT_ID;
228 client_config.clientid[OPT_LEN] = len;
229 client_config.clientid[OPT_DATA] = '\0';
230 strncpy((char*)client_config.clientid + OPT_DATA, optarg, len);
231 break;
232 case 'C':
233 if (client_config.clientid) show_usage();
234 no_clientid = 1;
235 break;
236 case 'V':
237 len = strlen(optarg) > 255 ? 255 : strlen(optarg);
238 free(client_config.vendorclass);
239 client_config.vendorclass = xmalloc(len + 2);
240 client_config.vendorclass[OPT_CODE] = DHCP_VENDOR;
241 client_config.vendorclass[OPT_LEN] = len;
242 strncpy((char*)client_config.vendorclass + OPT_DATA, optarg, len);
243 break;
244 case 'f':
245 client_config.foreground = 1;
246 break;
247 case 'b':
248 client_config.background_if_no_lease = 1;
249 break;
250 case 'h':
251 case 'H':
252 len = strlen(optarg) > 255 ? 255 : strlen(optarg);
253 free(client_config.hostname);
254 client_config.hostname = xmalloc(len + 2);
255 client_config.hostname[OPT_CODE] = DHCP_HOST_NAME;
256 client_config.hostname[OPT_LEN] = len;
257 strncpy((char*)client_config.hostname + 2, optarg, len);
258 break;
259 case 'F':
260 len = strlen(optarg) > 255 ? 255 : strlen(optarg);
261 free(client_config.fqdn);
262 client_config.fqdn = xmalloc(len + 5);
263 client_config.fqdn[OPT_CODE] = DHCP_FQDN;
264 client_config.fqdn[OPT_LEN] = len + 3;
265 /* Flags: 0000NEOS
266 S: 1 => Client requests Server to update A RR in DNS as well as PTR
267 O: 1 => Server indicates to client that DNS has been updated regardless
268 E: 1 => Name data is DNS format, i.e. <4>host<6>domain<4>com<0> not "host.domain.com"
269 N: 1 => Client requests Server to not update DNS
270 */
271 client_config.fqdn[OPT_LEN + 1] = 0x1;
272 client_config.fqdn[OPT_LEN + 2] = 0;
273 client_config.fqdn[OPT_LEN + 3] = 0;
274 strncpy((char*)client_config.fqdn + 5, optarg, len);
275 break;
276 case 'i':
277 client_config.interface = optarg;
278 break;
279 case 'n':
280 client_config.abort_if_no_lease = 1;
281 break;
282 case 'p':
283 client_config.pidfile = optarg;
284 break;
285 case 'q':
286 client_config.quit_after_lease = 1;
287 break;
288 case 'r':
289 requested_ip = inet_addr(optarg);
290 break;
291 case 's':
292 client_config.script = optarg;
293 break;
294 case 'T':
295 client_config.timeout = atoi(optarg);
296 break;
297 case 't':
298 client_config.retries = atoi(optarg);
299 break;
300 case 'v':
301 printf("udhcpcd, version %s\n\n", VERSION);
302 return 0;
303 break;
304 default:
305 show_usage();
306 }
307 }
308
309 /* Start the log, sanitize fd's, and write a pid file */
310 start_log_and_pid("udhcpc", client_config.pidfile);
311
312 if (read_interface(client_config.interface, &client_config.ifindex,
313 NULL, client_config.arp) < 0)
314 return 1;
315
316 /* if not set, and not suppressed, setup the default client ID */
317 if (!client_config.clientid && !no_clientid) {
318 client_config.clientid = xmalloc(6 + 3);
319 client_config.clientid[OPT_CODE] = DHCP_CLIENT_ID;
320 client_config.clientid[OPT_LEN] = 7;
321 client_config.clientid[OPT_DATA] = 1;
322 memcpy(client_config.clientid + 3, client_config.arp, 6);
323 }
324
325 if (!client_config.vendorclass) {
326 client_config.vendorclass = xmalloc(sizeof("udhcp "VERSION) + 2);
327 client_config.vendorclass[OPT_CODE] = DHCP_VENDOR;
328 client_config.vendorclass[OPT_LEN] = sizeof("udhcp "VERSION) - 1;
329 client_config.vendorclass[OPT_DATA] = 1;
330 memcpy(&client_config.vendorclass[OPT_DATA],
331 "udhcp "VERSION, sizeof("udhcp "VERSION) - 1);
332 }
333
334
335 /* setup the signal pipe */
336 udhcp_sp_setup();
337
338 state = INIT_SELECTING;
339 run_script(NULL, "deconfig");
340 change_mode(LISTEN_RAW);
341
342 for (;;) {
343
344 tv.tv_sec = timeout - uptime();
345 tv.tv_usec = 0;
346
347 if (listen_mode != LISTEN_NONE && fd < 0) {
348 if (listen_mode == LISTEN_KERNEL)
349 fd = listen_socket(INADDR_ANY, CLIENT_PORT, client_config.interface);
350 else
351 fd = raw_socket(client_config.ifindex);
352 if (fd < 0) {
353 LOG(LOG_ERR, "FATAL: couldn't listen on socket, %m");
354 return 0;
355 }
356 }
357 max_fd = udhcp_sp_fd_set(&rfds, fd);
358
359 if (tv.tv_sec > 0) {
360 DEBUG(LOG_INFO, "Waiting on select...");
361 retval = select(max_fd + 1, &rfds, NULL, NULL, &tv);
362 } else retval = 0; /* If we already timed out, fall through */
363
364 now = uptime();
365 if (retval == 0) {
366 /* timeout dropped to zero */
367 switch (state) {
368 case INIT_SELECTING:
369 if (packet_num < client_config.retries) {
370 if (packet_num == 0)
371 xid = random_xid();
372
373 /* send discover packet */
374 send_discover(xid, requested_ip); /* broadcast */
375
376 timeout = now + client_config.timeout;
377 packet_num++;
378 } else {
379 run_script(NULL, "leasefail");
380 if (client_config.background_if_no_lease) {
381 LOG(LOG_INFO, "No lease, forking to background.");
382 client_background();
383 } else if (client_config.abort_if_no_lease) {
384 LOG(LOG_INFO, "No lease, failing.");
385 return 1;
386 }
387 /* wait to try again */
388 packet_num = 0;
389 timeout = now + 60;
390 }
391 break;
392 case RENEW_REQUESTED:
393 case REQUESTING:
394 if (packet_num < client_config.retries) {
395 /* send request packet */
396 if (state == RENEW_REQUESTED)
397 send_renew(xid, server_addr, requested_ip); /* unicast */
398 else send_selecting(xid, server_addr, requested_ip); /* broadcast */
399
400 timeout = now + ((packet_num == 2) ? 10 : 2);
401 packet_num++;
402 } else {
403 /* timed out, go back to init state */
404 if (state == RENEW_REQUESTED) run_script(NULL, "deconfig");
405 state = INIT_SELECTING;
406 timeout = now;
407 packet_num = 0;
408 change_mode(LISTEN_RAW);
409 }
410 break;
411 case BOUND:
412 /* Lease is starting to run out, time to enter renewing state */
413 state = RENEWING;
414 change_mode(LISTEN_KERNEL);
415 DEBUG(LOG_INFO, "Entering renew state");
416 /* fall right through */
417 case RENEWING:
418 /* Either set a new T1, or enter REBINDING state */
419 if ((t2 - t1) <= (lease / 14400 + 1)) {
420 /* timed out, enter rebinding state */
421 state = REBINDING;
422 timeout = now + (t2 - t1);
423 DEBUG(LOG_INFO, "Entering rebinding state");
424 } else {
425 /* send a request packet */
426 send_renew(xid, server_addr, requested_ip); /* unicast */
427
428 t1 = (t2 - t1) / 2 + t1;
429 timeout = t1 + start;
430 }
431 break;
432 case REBINDING:
433 /* Either set a new T2, or enter INIT state */
434 if ((lease - t2) <= (lease / 14400 + 1)) {
435 /* timed out, enter init state */
436 state = INIT_SELECTING;
437 LOG(LOG_INFO, "Lease lost, entering init state");
438 run_script(NULL, "deconfig");
439 timeout = now;
440 packet_num = 0;
441 change_mode(LISTEN_RAW);
442 } else {
443 /* send a request packet */
444 send_renew(xid, 0, requested_ip); /* broadcast */
445
446 t2 = (lease - t2) / 2 + t2;
447 timeout = t2 + start;
448 }
449 break;
450 case RELEASED:
451 /* yah, I know, *you* say it would never happen */
452 timeout = 0x7fffffff;
453 break;
454 }
455 } else if (retval > 0 && listen_mode != LISTEN_NONE && FD_ISSET(fd, &rfds)) {
456 /* a packet is ready, read it */
457
458 if (listen_mode == LISTEN_KERNEL)
459 len = get_packet(&packet, fd);
460 else len = get_raw_packet(&packet, fd);
461
462 if (len == -1 && errno != EINTR) {
463 DEBUG(LOG_INFO, "error on read, %m, reopening socket");
464 change_mode(listen_mode); /* just close and reopen */
465 }
466 if (len < 0) continue;
467
468 if (packet.xid != xid) {
469 DEBUG(LOG_INFO, "Ignoring XID %lx (our xid is %lx)",
470 (unsigned long) packet.xid, xid);
471 continue;
472 }
473 /* Ignore packets that aren't for us */
474 if (memcmp(packet.chaddr, client_config.arp, 6)) {
475 DEBUG(LOG_INFO, "packet does not have our chaddr -- ignoring");
476 continue;
477 }
478
479 if ((message = get_option(&packet, DHCP_MESSAGE_TYPE)) == NULL) {
480 DEBUG(LOG_ERR, "couldnt get option from packet -- ignoring");
481 continue;
482 }
483
484 switch (state) {
485 case INIT_SELECTING:
486 /* Must be a DHCPOFFER to one of our xid's */
487 if (*message == DHCPOFFER) {
488 if ((temp = get_option(&packet, DHCP_SERVER_ID))) {
489 memcpy(&server_addr, temp, 4);
490 xid = packet.xid;
491 requested_ip = packet.yiaddr;
492
493 /* enter requesting state */
494 state = REQUESTING;
495 timeout = now;
496 packet_num = 0;
497 } else {
498 DEBUG(LOG_ERR, "No server ID in message");
499 }
500 }
501 break;
502 case RENEW_REQUESTED:
503 case REQUESTING:
504 case RENEWING:
505 case REBINDING:
506 if (*message == DHCPACK) {
507 if (!(temp = get_option(&packet, DHCP_LEASE_TIME))) {
508 LOG(LOG_ERR, "No lease time with ACK, using 1 hour lease");
509 lease = 60 * 60;
510 } else {
511 memcpy(&lease, temp, 4);
512 lease = ntohl(lease);
513 }
514
515 /* enter bound state */
516 t1 = lease / 2;
517
518 /* little fixed point for n * .875 */
519 t2 = (lease * 0x7) >> 3;
520 temp_addr.s_addr = packet.yiaddr;
521 LOG(LOG_INFO, "Lease of %s obtained, lease time %ld",
522 inet_ntoa(temp_addr), lease);
523 start = now;
524 timeout = t1 + start;
525 requested_ip = packet.yiaddr;
526 run_script(&packet,
527 ((state == RENEWING || state == REBINDING) ? "renew" : "bound"));
528
529 state = BOUND;
530 change_mode(LISTEN_NONE);
531 if (client_config.quit_after_lease)
532 return 0;
533 if (!client_config.foreground)
534 client_background();
535
536 } else if (*message == DHCPNAK) {
537 /* return to init state */
538 LOG(LOG_INFO, "Received DHCP NAK");
539 run_script(&packet, "nak");
540 if (state != REQUESTING)
541 run_script(NULL, "deconfig");
542 state = INIT_SELECTING;
543 timeout = now;
544 requested_ip = 0;
545 packet_num = 0;
546 change_mode(LISTEN_RAW);
547 sleep(3); /* avoid excessive network traffic */
548 }
549 break;
550 /* case BOUND, RELEASED: - ignore all packets */
551 }
552 } else if (retval > 0 && (sig = udhcp_sp_read(&rfds))) {
553 switch (sig) {
554 case SIGUSR1:
555 perform_renew();
556 break;
557 case SIGUSR2:
558 perform_release();
559 break;
560 case SIGTERM:
561 LOG(LOG_INFO, "Received SIGTERM");
562 return 0;
563 }
564 } else if (retval == -1 && errno == EINTR) {
565 /* a signal was caught */
566 } else {
567 /* An error occured */
568 DEBUG(LOG_ERR, "Error on select");
569 }
570
571 }
572 return 0;
573}
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