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Tomato 1.28
[tomato.git] / release / src / router / busybox / networking / udhcp / dhcpc.c
blob37a26a46cc4a4cb964b1d2ad5eb3bef33a185670
1 /* vi: set sw=4 ts=4: */
2 /* dhcpc.c
3 *
4 * udhcp DHCP client
5 *
6 * Russ Dill <Russ.Dill@asu.edu> July 2001
7 *
8 * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
9 */
10
11 #include <syslog.h>
12
13 /* Override ENABLE_FEATURE_PIDFILE - ifupdown needs our pidfile to always exist */
14 #define WANT_PIDFILE 1
15 #include "common.h"
16 #include "dhcpd.h"
17 #include "dhcpc.h"
18 #include "options.h"
19
20
21 static int sockfd = -1;
22
23 #define LISTEN_NONE 0
24 #define LISTEN_KERNEL 1
25 #define LISTEN_RAW 2
26 static smallint listen_mode;
27
28 /* initial state: (re)start DHCP negotiation */
29 #define INIT_SELECTING 0
30 /* discover was sent, DHCPOFFER reply received */
31 #define REQUESTING 1
32 /* select/renew was sent, DHCPACK reply received */
33 #define BOUND 2
34 /* half of lease passed, want renew it by sending unicast renew requests */
35 #define RENEWING 3
36 /* renew requests were not answered, lease is almost over, send broadcast renew */
37 #define REBINDING 4
38 /* manually requested renew (SIGUSR1) */
39 #define RENEW_REQUESTED 5
40 /* release, possibly manually requested (SIGUSR2) */
41 #define RELEASED 6
42 static smallint state;
43
44 /* struct client_config_t client_config is in bb_common_bufsiz1 */
45
46
47 /* just a little helper */
48 static void change_listen_mode(int new_mode)
49 {
50 DEBUG("Entering listen mode: %s",
51 new_mode != LISTEN_NONE
52 ? (new_mode == LISTEN_KERNEL ? "kernel" : "raw")
53 : "none"
54 );
55
56 listen_mode = new_mode;
57 if (sockfd >= 0) {
58 close(sockfd);
59 sockfd = -1;
60 }
61 if (new_mode == LISTEN_KERNEL)
62 sockfd = udhcp_listen_socket(/*INADDR_ANY,*/ CLIENT_PORT, client_config.interface);
63 else if (new_mode != LISTEN_NONE)
64 sockfd = udhcp_raw_socket(client_config.ifindex);
65 /* else LISTEN_NONE: sockfd stay closed */
66 }
67
68
69 /* perform a renew */
70 static void perform_renew(void)
71 {
72 bb_info_msg("Performing a DHCP renew");
73 switch (state) {
74 case BOUND:
75 change_listen_mode(LISTEN_RAW); // zzz
76 case RENEWING:
77 case REBINDING:
78 // state = RENEW_REQUESTED; // zzz
79 // break;
80 case RENEW_REQUESTED: /* impatient are we? fine, square 1 */
81 udhcp_run_script(NULL, "deconfig");
82 case REQUESTING:
83 case RELEASED:
84 change_listen_mode(LISTEN_RAW);
85 state = INIT_SELECTING;
86 break;
87 case INIT_SELECTING:
88 break;
89 }
90 }
91
92
93 /* perform a release */
94 static void perform_release(uint32_t requested_ip, uint32_t server_addr)
95 {
96 char buffer[sizeof("255.255.255.255")];
97 struct in_addr temp_addr;
98
99 /* send release packet */
100 if (state == BOUND || state == RENEWING || state == REBINDING) {
101 temp_addr.s_addr = server_addr;
102 strcpy(buffer, inet_ntoa(temp_addr));
103 temp_addr.s_addr = requested_ip;
104 bb_info_msg("Unicasting a release of %s to %s",
105 inet_ntoa(temp_addr), buffer);
106 send_release(server_addr, requested_ip); /* unicast */
107 udhcp_run_script(NULL, "deconfig");
108 }
109 bb_info_msg("Entering released state");
110
111 change_listen_mode(LISTEN_NONE);
112 state = RELEASED;
113 }
114
115
116 #if BB_MMU
117 static void client_background(void)
118 {
119 bb_daemonize(0);
120 logmode &= ~LOGMODE_STDIO;
121 /* rewrite pidfile, as our pid is different now */
122 write_pidfile(client_config.pidfile);
123 }
124 #endif
125
126
127 static uint8_t* alloc_dhcp_option(int code, const char *str, int extra)
128 {
129 uint8_t *storage;
130 int len = strlen(str);
131 if (len > 255) len = 255;
132 storage = xzalloc(len + extra + OPT_DATA);
133 storage[OPT_CODE] = code;
134 storage[OPT_LEN] = len + extra;
135 memcpy(storage + extra + OPT_DATA, str, len);
136 return storage;
137 }
138
139
140 int udhcpc_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
141 int udhcpc_main(int argc UNUSED_PARAM, char **argv)
142 {
143 uint8_t *temp, *message;
144 char *str_c, *str_V, *str_h, *str_F, *str_r;
145 USE_FEATURE_UDHCP_PORT(char *str_P;)
146 llist_t *list_O = NULL;
147 int tryagain_timeout = 20;
148 int discover_timeout = 3;
149 int discover_retries = 5;
150 uint32_t server_addr = server_addr; /* for compiler */
151 uint32_t requested_ip = 0;
152 uint32_t xid = 0;
153 uint32_t lease_seconds = 0; /* can be given as 32-bit quantity */
154 int packet_num;
155 int timeout; /* must be signed */
156 unsigned already_waited_sec;
157 unsigned opt;
158 int max_fd;
159 int retval;
160 struct timeval tv;
161 struct dhcpMessage packet;
162 fd_set rfds;
163
164 #if ENABLE_GETOPT_LONG
165 static const char udhcpc_longopts[] ALIGN1 =
166 "clientid\0" Required_argument "c"
167 "clientid-none\0" No_argument "C"
168 "vendorclass\0" Required_argument "V"
169 "hostname\0" Required_argument "H"
170 "fqdn\0" Required_argument "F"
171 "interface\0" Required_argument "i"
172 "now\0" No_argument "n"
173 "pidfile\0" Required_argument "p"
174 "quit\0" No_argument "q"
175 "release\0" No_argument "R"
176 "request\0" Required_argument "r"
177 "script\0" Required_argument "s"
178 "timeout\0" Required_argument "T"
179 "version\0" No_argument "v"
180 "retries\0" Required_argument "t"
181 "tryagain\0" Required_argument "A"
182 "syslog\0" No_argument "S"
183 "request-option\0" Required_argument "O"
184 "no-default-options\0" No_argument "o"
185 "foreground\0" No_argument "f"
186 "background\0" No_argument "b"
187 USE_FEATURE_UDHCPC_ARPING("arping\0" No_argument "a")
188 USE_FEATURE_UDHCP_PORT("client-port\0" Required_argument "P")
189 ;
190 #endif
191 enum {
192 OPT_c = 1 << 0,
193 OPT_C = 1 << 1,
194 OPT_V = 1 << 2,
195 OPT_H = 1 << 3,
196 OPT_h = 1 << 4,
197 OPT_F = 1 << 5,
198 OPT_i = 1 << 6,
199 OPT_n = 1 << 7,
200 OPT_p = 1 << 8,
201 OPT_q = 1 << 9,
202 OPT_R = 1 << 10,
203 OPT_r = 1 << 11,
204 OPT_s = 1 << 12,
205 OPT_T = 1 << 13,
206 OPT_t = 1 << 14,
207 OPT_v = 1 << 15,
208 OPT_S = 1 << 16,
209 OPT_A = 1 << 17,
210 OPT_O = 1 << 18,
211 OPT_o = 1 << 19,
212 OPT_f = 1 << 20,
213 OPT_m = 1 << 21, // zzz
214 /* The rest has variable bit positions, need to be clever */
215 OPTBIT_LAST = 21,
216 USE_FOR_MMU( OPTBIT_b,)
217 USE_FEATURE_UDHCPC_ARPING(OPTBIT_a,)
218 USE_FEATURE_UDHCP_PORT( OPTBIT_P,)
219 USE_FOR_MMU( OPT_b = 1 << OPTBIT_b,)
220 USE_FEATURE_UDHCPC_ARPING(OPT_a = 1 << OPTBIT_a,)
221 USE_FEATURE_UDHCP_PORT( OPT_P = 1 << OPTBIT_P,)
222 };
223
224 /* Default options. */
225 USE_FEATURE_UDHCP_PORT(SERVER_PORT = 67;)
226 USE_FEATURE_UDHCP_PORT(CLIENT_PORT = 68;)
227 client_config.interface = "eth0";
228 client_config.script = DEFAULT_SCRIPT;
229
230 /* Parse command line */
231 /* Cc: mutually exclusive; O: list; -T,-t,-A take numeric param */
232 opt_complementary = "c--C:C--c:O::T+:t+:A+";
233 USE_GETOPT_LONG(applet_long_options = udhcpc_longopts;)
234 opt = getopt32(argv, "c:CV:H:h:F:i:np:qRr:s:T:t:vSA:O:of"
235 "m" // zzz
236 USE_FOR_MMU("b")
237 USE_FEATURE_UDHCPC_ARPING("a")
238 USE_FEATURE_UDHCP_PORT("P:")
239 , &str_c, &str_V, &str_h, &str_h, &str_F
240 , &client_config.interface, &client_config.pidfile, &str_r /* i,p */
241 , &client_config.script /* s */
242 , &discover_timeout, &discover_retries, &tryagain_timeout /* T,t,A */
243 , &list_O
244 USE_FEATURE_UDHCP_PORT(, &str_P)
245 );
246 if (opt & OPT_c)
247 client_config.clientid = alloc_dhcp_option(DHCP_CLIENT_ID, str_c, 0);
248 if (opt & OPT_V)
249 client_config.vendorclass = alloc_dhcp_option(DHCP_VENDOR, str_V, 0);
250 if (opt & (OPT_h|OPT_H))
251 client_config.hostname = alloc_dhcp_option(DHCP_HOST_NAME, str_h, 0);
252 if (opt & OPT_F) {
253 client_config.fqdn = alloc_dhcp_option(DHCP_FQDN, str_F, 3);
254 /* Flags: 0000NEOS
255 S: 1 => Client requests Server to update A RR in DNS as well as PTR
256 O: 1 => Server indicates to client that DNS has been updated regardless
257 E: 1 => Name data is DNS format, i.e. <4>host<6>domain<3>com<0> not "host.domain.com"
258 N: 1 => Client requests Server to not update DNS
259 */
260 client_config.fqdn[OPT_DATA + 0] = 0x1;
261 /* client_config.fqdn[OPT_DATA + 1] = 0; - redundant */
262 /* client_config.fqdn[OPT_DATA + 2] = 0; - redundant */
263 }
264 if (opt & OPT_r)
265 requested_ip = inet_addr(str_r);
266 if (opt & OPT_v) {
267 puts("version "BB_VER);
268 return 0;
269 }
270 #if ENABLE_FEATURE_UDHCP_PORT
271 if (opt & OPT_P) {
272 CLIENT_PORT = xatou16(str_P);
273 SERVER_PORT = CLIENT_PORT - 1;
274 }
275 #endif
276 if (opt & OPT_o)
277 client_config.no_default_options = 1;
278 while (list_O) {
279 char *optstr = llist_pop(&list_O);
280 int n = index_in_strings(dhcp_option_strings, optstr);
281 if (n < 0)
282 bb_error_msg_and_die("unknown option '%s'", optstr);
283 n = dhcp_options[n].code;
284 client_config.opt_mask[n >> 3] |= 1 << (n & 7);
285 }
286 if (opt & OPT_m) minpkt = 1; // zzz
287
288 if (udhcp_read_interface(client_config.interface, &client_config.ifindex,
289 NULL, client_config.arp))
290 return 1;
291 #if !BB_MMU
292 /* on NOMMU reexec (i.e., background) early */
293 if (!(opt & OPT_f)) {
294 bb_daemonize_or_rexec(0 /* flags */, argv);
295 logmode = LOGMODE_NONE;
296 }
297 #endif
298 if (opt & OPT_S) {
299 openlog(applet_name, LOG_PID, LOG_DAEMON);
300 logmode |= LOGMODE_SYSLOG;
301 }
302
303 /* Make sure fd 0,1,2 are open */
304 bb_sanitize_stdio();
305 /* Equivalent of doing a fflush after every \n */
306 setlinebuf(stdout);
307
308 /* Create pidfile */
309 write_pidfile(client_config.pidfile);
310
311 /* Goes to stdout (unless NOMMU) and possibly syslog */
312 bb_info_msg("%s (v"BB_VER") started", applet_name);
313
314 /* if not set, and not suppressed, setup the default client ID */
315 if (!client_config.clientid && !(opt & OPT_C)) {
316 client_config.clientid = alloc_dhcp_option(DHCP_CLIENT_ID, "", 7);
317 client_config.clientid[OPT_DATA] = 1;
318 memcpy(client_config.clientid + OPT_DATA+1, client_config.arp, 6);
319 }
320
321 if (!client_config.vendorclass)
322 client_config.vendorclass = alloc_dhcp_option(DHCP_VENDOR, "udhcp "BB_VER, 0);
323
324 /* setup the signal pipe */
325 udhcp_sp_setup();
326
327 state = INIT_SELECTING;
328 udhcp_run_script(NULL, "deconfig");
329 change_listen_mode(LISTEN_RAW);
330 packet_num = 0;
331 timeout = 0;
332 already_waited_sec = 0;
333
334 /* Main event loop. select() waits on signal pipe and possibly
335 * on sockfd.
336 * "continue" statements in code below jump to the top of the loop.
337 */
338 for (;;) {
339 /* silence "uninitialized!" warning */
340 unsigned timestamp_before_wait = timestamp_before_wait;
341
342 //bb_error_msg("sockfd:%d, listen_mode:%d", sockfd, listen_mode);
343
344 /* Was opening raw or udp socket here
345 * if (listen_mode != LISTEN_NONE && sockfd < 0),
346 * but on fast network renew responses return faster
347 * than we open sockets. Thus this code is moved
348 * to change_listen_mode(). Thus we open listen socket
349 * BEFORE we send renew request (see "case BOUND:"). */
350
351 max_fd = udhcp_sp_fd_set(&rfds, sockfd);
352
353 tv.tv_sec = timeout - already_waited_sec;
354 tv.tv_usec = 0;
355 retval = 0; /* If we already timed out, fall through, else... */
356 if ((int)tv.tv_sec > 0) {
357 timestamp_before_wait = (unsigned)monotonic_sec();
358 DEBUG("Waiting on select...");
359 retval = select(max_fd + 1, &rfds, NULL, NULL, &tv);
360 if (retval < 0) {
361 /* EINTR? A signal was caught, don't panic */
362 if (errno == EINTR) {
363 already_waited_sec += (unsigned)monotonic_sec() - timestamp_before_wait;
364 continue;
365 }
366 /* Else: an error occured, panic! */
367 bb_perror_msg_and_die("select");
368 }
369 }
370
371 /* If timeout dropped to zero, time to become active:
372 * resend discover/renew/whatever
373 */
374 if (retval == 0) {
375 /* We will restart the wait in any case */
376 already_waited_sec = 0;
377
378 switch (state) {
379 case INIT_SELECTING:
380 if (packet_num < discover_retries) {
381 if (packet_num == 0)
382 xid = random_xid();
383
384 send_discover(xid, requested_ip); /* broadcast */
385
386 timeout = discover_timeout;
387 packet_num++;
388 continue;
389 }
390 leasefail:
391 udhcp_run_script(NULL, "leasefail");
392 #if BB_MMU /* -b is not supported on NOMMU */
393 if (opt & OPT_b) { /* background if no lease */
394 bb_info_msg("No lease, forking to background");
395 client_background();
396 /* do not background again! */
397 opt = ((opt & ~OPT_b) | OPT_f);
398 } else
399 #endif
400 if (opt & OPT_n) { /* abort if no lease */
401 bb_info_msg("No lease, failing");
402 retval = 1;
403 goto ret;
404 }
405 /* wait before trying again */
406 timeout = tryagain_timeout;
407 packet_num = 0;
408 continue;
409 case REQUESTING:
410 if (packet_num < discover_retries) {
411 /* send broadcast select packet */
412 send_select(xid, server_addr, requested_ip);
413 timeout = discover_timeout;
414 packet_num++;
415 continue;
416 }
417 /* Timed out, go back to init state.
418 * "discover...select...discover..." loops
419 * were seen in the wild. Treat them similarly
420 * to "no response to discover" case */
421 change_listen_mode(LISTEN_RAW);
422 state = INIT_SELECTING;
423 goto leasefail;
424 case BOUND:
425 /* Half of the lease passed, time to enter renewing state */
426 state = RENEWING;
427 change_listen_mode(LISTEN_RAW); // was: LISTEN_KERNEL -- zzz
428 DEBUG("Entering renew state");
429 /* fall right through */
430 case RENEW_REQUESTED: /* manual (SIGUSR1) renew */
431 case_RENEW_REQUESTED:
432 case RENEWING:
433 if (timeout > 60) {
434 /* send an unicast renew request packet */
435 send_renew(xid, server_addr, requested_ip);
436 timeout >>= 1;
437 continue;
438 }
439 /* Timed out, enter rebinding state */
440 DEBUG("Entering rebinding state");
441 state = REBINDING;
442 /* fall right through */
443 case REBINDING:
444 /* Switch to bcast receive */
445 change_listen_mode(LISTEN_RAW);
446 /* Lease is *really* about to run out,
447 * try to find DHCP server using broadcast */
448 if (timeout > 0) {
449 /* send a request packet */
450 send_renew(xid, 0 /*INADDR_ANY*/, requested_ip); /* broadcast */
451 timeout >>= 1;
452 continue;
453 }
454 /* Timed out, enter init state */
455 bb_info_msg("Lease lost, entering init state");
456 udhcp_run_script(NULL, "deconfig");
457 state = INIT_SELECTING;
458 /*timeout = 0; - already is */
459 packet_num = 0;
460 continue;
461 /* case RELEASED: */
462 }
463 /* yah, I know, *you* say it would never happen */
464 timeout = INT_MAX;
465 continue; /* back to main loop */
466 } /* if select timed out */
467
468 /* select() didn't timeout, something happened */
469
470 /* Is it a signal? */
471 /* note: udhcp_sp_read checks FD_ISSET before reading */
472 switch (udhcp_sp_read(&rfds)) {
473 case SIGUSR1:
474 perform_renew();
475 if (state == RENEW_REQUESTED)
476 goto case_RENEW_REQUESTED;
477 /* Start things over */
478 packet_num = 0;
479 /* Kill any timeouts because the user wants this to hurry along */
480 timeout = 0;
481 continue;
482 case SIGUSR2:
483 perform_release(requested_ip, server_addr);
484 timeout = INT_MAX;
485 continue;
486 case SIGTERM:
487 bb_info_msg("Received SIGTERM");
488 if (opt & OPT_R) /* release on quit */
489 perform_release(requested_ip, server_addr);
490 goto ret0;
491 }
492
493 /* Is it a packet? */
494 if (listen_mode == LISTEN_NONE || !FD_ISSET(sockfd, &rfds))
495 continue; /* no */
496
497 {
498 int len;
499
500 /* A packet is ready, read it */
501 if (listen_mode == LISTEN_KERNEL)
502 len = udhcp_recv_kernel_packet(&packet, sockfd);
503 else
504 len = udhcp_recv_raw_packet(&packet, sockfd);
505 if (len == -1) {
506 /* Error is severe, reopen socket */
507 bb_info_msg("Read error: %s, reopening socket", strerror(errno));
508 sleep(discover_timeout); /* 3 seconds by default */
509 change_listen_mode(listen_mode); /* just close and reopen */
510 }
511 /* If this packet will turn out to be unrelated/bogus,
512 * we will go back and wait for next one.
513 * Be sure timeout is properly decreased. */
514 already_waited_sec += (unsigned)monotonic_sec() - timestamp_before_wait;
515 if (len < 0)
516 continue;
517 }
518
519 if (packet.xid != xid) {
520 DEBUG("xid %x (our is %x), ignoring packet",
521 (unsigned)packet.xid, (unsigned)xid);
522 continue;
523 }
524
525 /* Ignore packets that aren't for us */
526 if (memcmp(packet.chaddr, client_config.arp, 6)) {
527 DEBUG("Packet does not have our chaddr - ignoring");
528 continue;
529 }
530
531 message = get_option(&packet, DHCP_MESSAGE_TYPE);
532 if (message == NULL) {
533 bb_error_msg("no message type option, ignoring packet");
534 continue;
535 }
536
537 switch (state) {
538 case INIT_SELECTING:
539 /* Must be a DHCPOFFER to one of our xid's */
540 if (*message == DHCPOFFER) {
541 /* TODO: why we don't just fetch server's IP from IP header? */
542 temp = get_option(&packet, DHCP_SERVER_ID);
543 if (!temp) {
544 bb_error_msg("no server ID in message");
545 continue;
546 /* still selecting - this server looks bad */
547 }
548 /* it IS unaligned sometimes, don't "optimize" */
549 move_from_unaligned32(server_addr, temp);
550 xid = packet.xid;
551 requested_ip = packet.yiaddr;
552
553 /* enter requesting state */
554 state = REQUESTING;
555 timeout = 0;
556 packet_num = 0;
557 already_waited_sec = 0;
558 }
559 continue;
560 case REQUESTING:
561 case RENEWING:
562 case RENEW_REQUESTED:
563 case REBINDING:
564 if (*message == DHCPACK) {
565 temp = get_option(&packet, DHCP_LEASE_TIME);
566 if (!temp) {
567 bb_error_msg("no lease time with ACK, using 1 hour lease");
568 lease_seconds = 60 * 60;
569 } else {
570 /* it IS unaligned sometimes, don't "optimize" */
571 move_from_unaligned32(lease_seconds, temp);
572 lease_seconds = ntohl(lease_seconds);
573 lease_seconds &= 0x0fffffff; /* paranoia: must not be prone to overflows */
574 if (lease_seconds < 10) /* and not too small */
575 lease_seconds = 10;
576 }
577 #if ENABLE_FEATURE_UDHCPC_ARPING
578 if (opt & OPT_a) {
579 /* RFC 2131 3.1 paragraph 5:
580 * "The client receives the DHCPACK message with configuration
581 * parameters. The client SHOULD perform a final check on the
582 * parameters (e.g., ARP for allocated network address), and notes
583 * the duration of the lease specified in the DHCPACK message. At this
584 * point, the client is configured. If the client detects that the
585 * address is already in use (e.g., through the use of ARP),
586 * the client MUST send a DHCPDECLINE message to the server and restarts
587 * the configuration process..." */
588 if (!arpping(packet.yiaddr,
589 (uint32_t) 0,
590 client_config.arp,
591 client_config.interface)
592 ) {
593 bb_info_msg("Offered address is in use "
594 "(got ARP reply), declining");
595 send_decline(xid, server_addr, packet.yiaddr);
596
597 if (state != REQUESTING)
598 udhcp_run_script(NULL, "deconfig");
599 change_listen_mode(LISTEN_RAW);
600 state = INIT_SELECTING;
601 requested_ip = 0;
602 timeout = tryagain_timeout;
603 packet_num = 0;
604 already_waited_sec = 0;
605 continue; /* back to main loop */
606 }
607 }
608 #endif
609 /* enter bound state */
610 timeout = lease_seconds / 2;
611 {
612 struct in_addr temp_addr;
613 temp_addr.s_addr = packet.yiaddr;
614 bb_info_msg("Lease of %s obtained, lease time %u",
615 inet_ntoa(temp_addr), (unsigned)lease_seconds);
616 }
617 requested_ip = packet.yiaddr;
618 udhcp_run_script(&packet, state == REQUESTING ? "bound" : "renew");
619
620 state = BOUND;
621 change_listen_mode(LISTEN_NONE);
622 if (opt & OPT_q) { /* quit after lease */
623 if (opt & OPT_R) /* release on quit */
624 perform_release(requested_ip, server_addr);
625 goto ret0;
626 }
627 /* future renew failures should not exit (JM) */
628 opt &= ~OPT_n;
629 #if BB_MMU /* NOMMU case backgrounded earlier */
630 if (!(opt & OPT_f)) {
631 client_background();
632 /* do not background again! */
633 opt = ((opt & ~OPT_b) | OPT_f);
634 }
635 #endif
636 already_waited_sec = 0;
637 continue; /* back to main loop */
638 }
639 if (*message == DHCPNAK) {
640 /* return to init state */
641 bb_info_msg("Received DHCP NAK");
642 udhcp_run_script(&packet, "nak");
643 if (state != REQUESTING)
644 udhcp_run_script(NULL, "deconfig");
645 change_listen_mode(LISTEN_RAW);
646 sleep(3); /* avoid excessive network traffic */
647 state = INIT_SELECTING;
648 requested_ip = 0;
649 timeout = 0;
650 packet_num = 0;
651 already_waited_sec = 0;
652 }
653 continue;
654 /* case BOUND: - ignore all packets */
655 /* case RELEASED: - ignore all packets */
656 }
657 /* back to main loop */
658 } /* for (;;) - main loop ends */
659
660 ret0:
661 retval = 0;
662 ret:
663 /*if (client_config.pidfile) - remove_pidfile has its own check */
664 remove_pidfile(client_config.pidfile);
665 return retval;
666 }
Tomato firmware and modifications.