source: MondoRescue/branches/3.2/mindi-busybox/networking/udhcp/dhcpc.c@ 3306

Last change on this file since 3306 was 3306, checked in by Bruno Cornec, 10 years ago
  • Fix busybox 1.21.1 to support back old distributions such as RHEL3 and RHEL4 or SLES9 by avoiding usgae of the struct tpacket_auxdata
File size: 55.7 KB
Line 
1/* vi: set sw=4 ts=4: */
2/*
3 * udhcp client
4 *
5 * Russ Dill <Russ.Dill@asu.edu> July 2001
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20 */
21#include <syslog.h>
22/* Override ENABLE_FEATURE_PIDFILE - ifupdown needs our pidfile to always exist */
23#define WANT_PIDFILE 1
24#include "common.h"
25#include "dhcpd.h"
26#include "dhcpc.h"
27
28#include <asm/types.h>
29#if (defined(__GLIBC__) && __GLIBC__ >= 2 && __GLIBC_MINOR__ >= 1) || defined(_NEWLIB_VERSION)
30# include <netpacket/packet.h>
31# include <net/ethernet.h>
32#else
33# include <linux/if_packet.h>
34# include <linux/if_ether.h>
35#endif
36#include <linux/filter.h>
37
38/* "struct client_config_t client_config" is in bb_common_bufsiz1 */
39
40
41#if ENABLE_LONG_OPTS
42static const char udhcpc_longopts[] ALIGN1 =
43 "clientid-none\0" No_argument "C"
44 "vendorclass\0" Required_argument "V"
45 "hostname\0" Required_argument "H"
46 "fqdn\0" Required_argument "F"
47 "interface\0" Required_argument "i"
48 "now\0" No_argument "n"
49 "pidfile\0" Required_argument "p"
50 "quit\0" No_argument "q"
51 "release\0" No_argument "R"
52 "request\0" Required_argument "r"
53 "script\0" Required_argument "s"
54 "timeout\0" Required_argument "T"
55 "retries\0" Required_argument "t"
56 "tryagain\0" Required_argument "A"
57 "syslog\0" No_argument "S"
58 "request-option\0" Required_argument "O"
59 "no-default-options\0" No_argument "o"
60 "foreground\0" No_argument "f"
61 "background\0" No_argument "b"
62 "broadcast\0" No_argument "B"
63 IF_FEATURE_UDHCPC_ARPING("arping\0" No_argument "a")
64 IF_FEATURE_UDHCP_PORT("client-port\0" Required_argument "P")
65 ;
66#endif
67/* Must match getopt32 option string order */
68enum {
69 OPT_C = 1 << 0,
70 OPT_V = 1 << 1,
71 OPT_H = 1 << 2,
72 OPT_h = 1 << 3,
73 OPT_F = 1 << 4,
74 OPT_i = 1 << 5,
75 OPT_n = 1 << 6,
76 OPT_p = 1 << 7,
77 OPT_q = 1 << 8,
78 OPT_R = 1 << 9,
79 OPT_r = 1 << 10,
80 OPT_s = 1 << 11,
81 OPT_T = 1 << 12,
82 OPT_t = 1 << 13,
83 OPT_S = 1 << 14,
84 OPT_A = 1 << 15,
85 OPT_O = 1 << 16,
86 OPT_o = 1 << 17,
87 OPT_x = 1 << 18,
88 OPT_f = 1 << 19,
89 OPT_B = 1 << 20,
90/* The rest has variable bit positions, need to be clever */
91 OPTBIT_B = 20,
92 USE_FOR_MMU( OPTBIT_b,)
93 IF_FEATURE_UDHCPC_ARPING(OPTBIT_a,)
94 IF_FEATURE_UDHCP_PORT( OPTBIT_P,)
95 USE_FOR_MMU( OPT_b = 1 << OPTBIT_b,)
96 IF_FEATURE_UDHCPC_ARPING(OPT_a = 1 << OPTBIT_a,)
97 IF_FEATURE_UDHCP_PORT( OPT_P = 1 << OPTBIT_P,)
98};
99
100
101/*** Script execution code ***/
102
103/* get a rough idea of how long an option will be (rounding up...) */
104static const uint8_t len_of_option_as_string[] = {
105 [OPTION_IP ] = sizeof("255.255.255.255 "),
106 [OPTION_IP_PAIR ] = sizeof("255.255.255.255 ") * 2,
107 [OPTION_STATIC_ROUTES ] = sizeof("255.255.255.255/32 255.255.255.255 "),
108 [OPTION_6RD ] = sizeof("32 128 ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff 255.255.255.255 "),
109 [OPTION_STRING ] = 1,
110 [OPTION_STRING_HOST ] = 1,
111#if ENABLE_FEATURE_UDHCP_RFC3397
112 [OPTION_DNS_STRING ] = 1, /* unused */
113 /* Hmmm, this severely overestimates size if SIP_SERVERS option
114 * is in domain name form: N-byte option in binary form
115 * mallocs ~16*N bytes. But it is freed almost at once.
116 */
117 [OPTION_SIP_SERVERS ] = sizeof("255.255.255.255 "),
118#endif
119// [OPTION_BOOLEAN ] = sizeof("yes "),
120 [OPTION_U8 ] = sizeof("255 "),
121 [OPTION_U16 ] = sizeof("65535 "),
122// [OPTION_S16 ] = sizeof("-32768 "),
123 [OPTION_U32 ] = sizeof("4294967295 "),
124 [OPTION_S32 ] = sizeof("-2147483684 "),
125};
126
127/* note: ip is a pointer to an IP in network order, possibly misaliged */
128static int sprint_nip(char *dest, const char *pre, const uint8_t *ip)
129{
130 return sprintf(dest, "%s%u.%u.%u.%u", pre, ip[0], ip[1], ip[2], ip[3]);
131}
132
133/* really simple implementation, just count the bits */
134static int mton(uint32_t mask)
135{
136 int i = 0;
137 mask = ntohl(mask); /* 111110000-like bit pattern */
138 while (mask) {
139 i++;
140 mask <<= 1;
141 }
142 return i;
143}
144
145/* Check if a given label represents a valid DNS label
146 * Return pointer to the first character after the label upon success,
147 * NULL otherwise.
148 * See RFC1035, 2.3.1
149 */
150/* We don't need to be particularly anal. For example, allowing _, hyphen
151 * at the end, or leading and trailing dots would be ok, since it
152 * can't be used for attacks. (Leading hyphen can be, if someone uses
153 * cmd "$hostname"
154 * in the script: then hostname may be treated as an option)
155 */
156static const char *valid_domain_label(const char *label)
157{
158 unsigned char ch;
159 unsigned pos = 0;
160
161 for (;;) {
162 ch = *label;
163 if ((ch|0x20) < 'a' || (ch|0x20) > 'z') {
164 if (pos == 0) {
165 /* label must begin with letter */
166 return NULL;
167 }
168 if (ch < '0' || ch > '9') {
169 if (ch == '\0' || ch == '.')
170 return label;
171 /* DNS allows only '-', but we are more permissive */
172 if (ch != '-' && ch != '_')
173 return NULL;
174 }
175 }
176 label++;
177 pos++;
178 //Do we want this?
179 //if (pos > 63) /* NS_MAXLABEL; labels must be 63 chars or less */
180 // return NULL;
181 }
182}
183
184/* Check if a given name represents a valid DNS name */
185/* See RFC1035, 2.3.1 */
186static int good_hostname(const char *name)
187{
188 //const char *start = name;
189
190 for (;;) {
191 name = valid_domain_label(name);
192 if (!name)
193 return 0;
194 if (!name[0])
195 return 1;
196 //Do we want this?
197 //return ((name - start) < 1025); /* NS_MAXDNAME */
198 name++;
199 }
200}
201
202/* Create "opt_name=opt_value" string */
203static NOINLINE char *xmalloc_optname_optval(uint8_t *option, const struct dhcp_optflag *optflag, const char *opt_name)
204{
205 unsigned upper_length;
206 int len, type, optlen;
207 char *dest, *ret;
208
209 /* option points to OPT_DATA, need to go back to get OPT_LEN */
210 len = option[-OPT_DATA + OPT_LEN];
211
212 type = optflag->flags & OPTION_TYPE_MASK;
213 optlen = dhcp_option_lengths[type];
214 upper_length = len_of_option_as_string[type]
215 * ((unsigned)(len + optlen - 1) / (unsigned)optlen);
216
217 dest = ret = xmalloc(upper_length + strlen(opt_name) + 2);
218 dest += sprintf(ret, "%s=", opt_name);
219
220 while (len >= optlen) {
221 switch (type) {
222 case OPTION_IP:
223 case OPTION_IP_PAIR:
224 dest += sprint_nip(dest, "", option);
225 if (type == OPTION_IP)
226 break;
227 dest += sprint_nip(dest, "/", option + 4);
228 break;
229// case OPTION_BOOLEAN:
230// dest += sprintf(dest, *option ? "yes" : "no");
231// break;
232 case OPTION_U8:
233 dest += sprintf(dest, "%u", *option);
234 break;
235// case OPTION_S16:
236 case OPTION_U16: {
237 uint16_t val_u16;
238 move_from_unaligned16(val_u16, option);
239 dest += sprintf(dest, "%u", ntohs(val_u16));
240 break;
241 }
242 case OPTION_S32:
243 case OPTION_U32: {
244 uint32_t val_u32;
245 move_from_unaligned32(val_u32, option);
246 dest += sprintf(dest, type == OPTION_U32 ? "%lu" : "%ld", (unsigned long) ntohl(val_u32));
247 break;
248 }
249 /* Note: options which use 'return' instead of 'break'
250 * (for example, OPTION_STRING) skip the code which handles
251 * the case of list of options.
252 */
253 case OPTION_STRING:
254 case OPTION_STRING_HOST:
255 memcpy(dest, option, len);
256 dest[len] = '\0';
257 if (type == OPTION_STRING_HOST && !good_hostname(dest))
258 safe_strncpy(dest, "bad", len);
259 return ret;
260 case OPTION_STATIC_ROUTES: {
261 /* Option binary format:
262 * mask [one byte, 0..32]
263 * ip [big endian, 0..4 bytes depending on mask]
264 * router [big endian, 4 bytes]
265 * may be repeated
266 *
267 * We convert it to a string "IP/MASK ROUTER IP2/MASK2 ROUTER2"
268 */
269 const char *pfx = "";
270
271 while (len >= 1 + 4) { /* mask + 0-byte ip + router */
272 uint32_t nip;
273 uint8_t *p;
274 unsigned mask;
275 int bytes;
276
277 mask = *option++;
278 if (mask > 32)
279 break;
280 len--;
281
282 nip = 0;
283 p = (void*) &nip;
284 bytes = (mask + 7) / 8; /* 0 -> 0, 1..8 -> 1, 9..16 -> 2 etc */
285 while (--bytes >= 0) {
286 *p++ = *option++;
287 len--;
288 }
289 if (len < 4)
290 break;
291
292 /* print ip/mask */
293 dest += sprint_nip(dest, pfx, (void*) &nip);
294 pfx = " ";
295 dest += sprintf(dest, "/%u ", mask);
296 /* print router */
297 dest += sprint_nip(dest, "", option);
298 option += 4;
299 len -= 4;
300 }
301
302 return ret;
303 }
304 case OPTION_6RD:
305 /* Option binary format (see RFC 5969):
306 * 0 1 2 3
307 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
308 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
309 * | OPTION_6RD | option-length | IPv4MaskLen | 6rdPrefixLen |
310 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
311 * | 6rdPrefix |
312 * ... (16 octets) ...
313 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
314 * ... 6rdBRIPv4Address(es) ...
315 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
316 * We convert it to a string
317 * "IPv4MaskLen 6rdPrefixLen 6rdPrefix 6rdBRIPv4Address..."
318 *
319 * Sanity check: ensure that our length is at least 22 bytes, that
320 * IPv4MaskLen <= 32,
321 * 6rdPrefixLen <= 128,
322 * 6rdPrefixLen + (32 - IPv4MaskLen) <= 128
323 * (2nd condition need no check - it follows from 1st and 3rd).
324 * Else, return envvar with empty value ("optname=")
325 */
326 if (len >= (1 + 1 + 16 + 4)
327 && option[0] <= 32
328 && (option[1] + 32 - option[0]) <= 128
329 ) {
330 /* IPv4MaskLen */
331 dest += sprintf(dest, "%u ", *option++);
332 /* 6rdPrefixLen */
333 dest += sprintf(dest, "%u ", *option++);
334 /* 6rdPrefix */
335 dest += sprint_nip6(dest, /* "", */ option);
336 option += 16;
337 len -= 1 + 1 + 16 + 4;
338 /* "+ 4" above corresponds to the length of IPv4 addr
339 * we consume in the loop below */
340 while (1) {
341 /* 6rdBRIPv4Address(es) */
342 dest += sprint_nip(dest, " ", option);
343 option += 4;
344 len -= 4; /* do we have yet another 4+ bytes? */
345 if (len < 0)
346 break; /* no */
347 }
348 }
349
350 return ret;
351#if ENABLE_FEATURE_UDHCP_RFC3397
352 case OPTION_DNS_STRING:
353 /* unpack option into dest; use ret for prefix (i.e., "optname=") */
354 dest = dname_dec(option, len, ret);
355 if (dest) {
356 free(ret);
357 return dest;
358 }
359 /* error. return "optname=" string */
360 return ret;
361 case OPTION_SIP_SERVERS:
362 /* Option binary format:
363 * type: byte
364 * type=0: domain names, dns-compressed
365 * type=1: IP addrs
366 */
367 option++;
368 len--;
369 if (option[-1] == 0) {
370 dest = dname_dec(option, len, ret);
371 if (dest) {
372 free(ret);
373 return dest;
374 }
375 } else
376 if (option[-1] == 1) {
377 const char *pfx = "";
378 while (1) {
379 len -= 4;
380 if (len < 0)
381 break;
382 dest += sprint_nip(dest, pfx, option);
383 pfx = " ";
384 option += 4;
385 }
386 }
387 return ret;
388#endif
389 } /* switch */
390
391 /* If we are here, try to format any remaining data
392 * in the option as another, similarly-formatted option
393 */
394 option += optlen;
395 len -= optlen;
396// TODO: it can be a list only if (optflag->flags & OPTION_LIST).
397// Should we bail out/warn if we see multi-ip option which is
398// not allowed to be such (for example, DHCP_BROADCAST)? -
399 if (len < optlen /* || !(optflag->flags & OPTION_LIST) */)
400 break;
401 *dest++ = ' ';
402 *dest = '\0';
403 } /* while */
404
405 return ret;
406}
407
408/* put all the parameters into the environment */
409static char **fill_envp(struct dhcp_packet *packet)
410{
411 int envc;
412 int i;
413 char **envp, **curr;
414 const char *opt_name;
415 uint8_t *temp;
416 uint8_t overload = 0;
417
418#define BITMAP unsigned
419#define BBITS (sizeof(BITMAP) * 8)
420#define BMASK(i) (1 << (i & (sizeof(BITMAP) * 8 - 1)))
421#define FOUND_OPTS(i) (found_opts[(unsigned)i / BBITS])
422 BITMAP found_opts[256 / BBITS];
423
424 memset(found_opts, 0, sizeof(found_opts));
425
426 /* We need 6 elements for:
427 * "interface=IFACE"
428 * "ip=N.N.N.N" from packet->yiaddr
429 * "siaddr=IP" from packet->siaddr_nip (unless 0)
430 * "boot_file=FILE" from packet->file (unless overloaded)
431 * "sname=SERVER_HOSTNAME" from packet->sname (unless overloaded)
432 * terminating NULL
433 */
434 envc = 6;
435 /* +1 element for each option, +2 for subnet option: */
436 if (packet) {
437 /* note: do not search for "pad" (0) and "end" (255) options */
438//TODO: change logic to scan packet _once_
439 for (i = 1; i < 255; i++) {
440 temp = udhcp_get_option(packet, i);
441 if (temp) {
442 if (i == DHCP_OPTION_OVERLOAD)
443 overload = *temp;
444 else if (i == DHCP_SUBNET)
445 envc++; /* for $mask */
446 envc++;
447 /*if (i != DHCP_MESSAGE_TYPE)*/
448 FOUND_OPTS(i) |= BMASK(i);
449 }
450 }
451 }
452 curr = envp = xzalloc(sizeof(envp[0]) * envc);
453
454 *curr = xasprintf("interface=%s", client_config.interface);
455 putenv(*curr++);
456
457 if (!packet)
458 return envp;
459
460 /* Export BOOTP fields. Fields we don't (yet?) export:
461 * uint8_t op; // always BOOTREPLY
462 * uint8_t htype; // hardware address type. 1 = 10mb ethernet
463 * uint8_t hlen; // hardware address length
464 * uint8_t hops; // used by relay agents only
465 * uint32_t xid;
466 * uint16_t secs; // elapsed since client began acquisition/renewal
467 * uint16_t flags; // only one flag so far: bcast. Never set by server
468 * uint32_t ciaddr; // client IP (usually == yiaddr. can it be different
469 * // if during renew server wants to give us differn IP?)
470 * uint32_t gateway_nip; // relay agent IP address
471 * uint8_t chaddr[16]; // link-layer client hardware address (MAC)
472 * TODO: export gateway_nip as $giaddr?
473 */
474 /* Most important one: yiaddr as $ip */
475 *curr = xmalloc(sizeof("ip=255.255.255.255"));
476 sprint_nip(*curr, "ip=", (uint8_t *) &packet->yiaddr);
477 putenv(*curr++);
478 if (packet->siaddr_nip) {
479 /* IP address of next server to use in bootstrap */
480 *curr = xmalloc(sizeof("siaddr=255.255.255.255"));
481 sprint_nip(*curr, "siaddr=", (uint8_t *) &packet->siaddr_nip);
482 putenv(*curr++);
483 }
484 if (!(overload & FILE_FIELD) && packet->file[0]) {
485 /* watch out for invalid packets */
486 *curr = xasprintf("boot_file=%."DHCP_PKT_FILE_LEN_STR"s", packet->file);
487 putenv(*curr++);
488 }
489 if (!(overload & SNAME_FIELD) && packet->sname[0]) {
490 /* watch out for invalid packets */
491 *curr = xasprintf("sname=%."DHCP_PKT_SNAME_LEN_STR"s", packet->sname);
492 putenv(*curr++);
493 }
494
495 /* Export known DHCP options */
496 opt_name = dhcp_option_strings;
497 i = 0;
498 while (*opt_name) {
499 uint8_t code = dhcp_optflags[i].code;
500 BITMAP *found_ptr = &FOUND_OPTS(code);
501 BITMAP found_mask = BMASK(code);
502 if (!(*found_ptr & found_mask))
503 goto next;
504 *found_ptr &= ~found_mask; /* leave only unknown options */
505 temp = udhcp_get_option(packet, code);
506 *curr = xmalloc_optname_optval(temp, &dhcp_optflags[i], opt_name);
507 putenv(*curr++);
508 if (code == DHCP_SUBNET) {
509 /* Subnet option: make things like "$ip/$mask" possible */
510 uint32_t subnet;
511 move_from_unaligned32(subnet, temp);
512 *curr = xasprintf("mask=%u", mton(subnet));
513 putenv(*curr++);
514 }
515 next:
516 opt_name += strlen(opt_name) + 1;
517 i++;
518 }
519 /* Export unknown options */
520 for (i = 0; i < 256;) {
521 BITMAP bitmap = FOUND_OPTS(i);
522 if (!bitmap) {
523 i += BBITS;
524 continue;
525 }
526 if (bitmap & BMASK(i)) {
527 unsigned len, ofs;
528
529 temp = udhcp_get_option(packet, i);
530 /* udhcp_get_option returns ptr to data portion,
531 * need to go back to get len
532 */
533 len = temp[-OPT_DATA + OPT_LEN];
534 *curr = xmalloc(sizeof("optNNN=") + 1 + len*2);
535 ofs = sprintf(*curr, "opt%u=", i);
536 *bin2hex(*curr + ofs, (void*) temp, len) = '\0';
537 putenv(*curr++);
538 }
539 i++;
540 }
541
542 return envp;
543}
544
545/* Call a script with a par file and env vars */
546static void udhcp_run_script(struct dhcp_packet *packet, const char *name)
547{
548 char **envp, **curr;
549 char *argv[3];
550
551 envp = fill_envp(packet);
552
553 /* call script */
554 log1("Executing %s %s", client_config.script, name);
555 argv[0] = (char*) client_config.script;
556 argv[1] = (char*) name;
557 argv[2] = NULL;
558 spawn_and_wait(argv);
559
560 for (curr = envp; *curr; curr++) {
561 log2(" %s", *curr);
562 bb_unsetenv_and_free(*curr);
563 }
564 free(envp);
565}
566
567
568/*** Sending/receiving packets ***/
569
570static ALWAYS_INLINE uint32_t random_xid(void)
571{
572 return rand();
573}
574
575/* Initialize the packet with the proper defaults */
576static void init_packet(struct dhcp_packet *packet, char type)
577{
578 uint16_t secs;
579
580 /* Fill in: op, htype, hlen, cookie fields; message type option: */
581 udhcp_init_header(packet, type);
582
583 packet->xid = random_xid();
584
585 client_config.last_secs = monotonic_sec();
586 if (client_config.first_secs == 0)
587 client_config.first_secs = client_config.last_secs;
588 secs = client_config.last_secs - client_config.first_secs;
589 packet->secs = htons(secs);
590
591 memcpy(packet->chaddr, client_config.client_mac, 6);
592 if (client_config.clientid)
593 udhcp_add_binary_option(packet, client_config.clientid);
594}
595
596static void add_client_options(struct dhcp_packet *packet)
597{
598 int i, end, len;
599
600 udhcp_add_simple_option(packet, DHCP_MAX_SIZE, htons(IP_UDP_DHCP_SIZE));
601
602 /* Add a "param req" option with the list of options we'd like to have
603 * from stubborn DHCP servers. Pull the data from the struct in common.c.
604 * No bounds checking because it goes towards the head of the packet. */
605 end = udhcp_end_option(packet->options);
606 len = 0;
607 for (i = 1; i < DHCP_END; i++) {
608 if (client_config.opt_mask[i >> 3] & (1 << (i & 7))) {
609 packet->options[end + OPT_DATA + len] = i;
610 len++;
611 }
612 }
613 if (len) {
614 packet->options[end + OPT_CODE] = DHCP_PARAM_REQ;
615 packet->options[end + OPT_LEN] = len;
616 packet->options[end + OPT_DATA + len] = DHCP_END;
617 }
618
619 if (client_config.vendorclass)
620 udhcp_add_binary_option(packet, client_config.vendorclass);
621 if (client_config.hostname)
622 udhcp_add_binary_option(packet, client_config.hostname);
623 if (client_config.fqdn)
624 udhcp_add_binary_option(packet, client_config.fqdn);
625
626 /* Request broadcast replies if we have no IP addr */
627 if ((option_mask32 & OPT_B) && packet->ciaddr == 0)
628 packet->flags |= htons(BROADCAST_FLAG);
629
630 /* Add -x options if any */
631 {
632 struct option_set *curr = client_config.options;
633 while (curr) {
634 udhcp_add_binary_option(packet, curr->data);
635 curr = curr->next;
636 }
637// if (client_config.sname)
638// strncpy((char*)packet->sname, client_config.sname, sizeof(packet->sname) - 1);
639// if (client_config.boot_file)
640// strncpy((char*)packet->file, client_config.boot_file, sizeof(packet->file) - 1);
641 }
642
643 // This will be needed if we remove -V VENDOR_STR in favor of
644 // -x vendor:VENDOR_STR
645 //if (!udhcp_find_option(packet.options, DHCP_VENDOR))
646 // /* not set, set the default vendor ID */
647 // ...add (DHCP_VENDOR, "udhcp "BB_VER) opt...
648}
649
650/* RFC 2131
651 * 4.4.4 Use of broadcast and unicast
652 *
653 * The DHCP client broadcasts DHCPDISCOVER, DHCPREQUEST and DHCPINFORM
654 * messages, unless the client knows the address of a DHCP server.
655 * The client unicasts DHCPRELEASE messages to the server. Because
656 * the client is declining the use of the IP address supplied by the server,
657 * the client broadcasts DHCPDECLINE messages.
658 *
659 * When the DHCP client knows the address of a DHCP server, in either
660 * INIT or REBOOTING state, the client may use that address
661 * in the DHCPDISCOVER or DHCPREQUEST rather than the IP broadcast address.
662 * The client may also use unicast to send DHCPINFORM messages
663 * to a known DHCP server. If the client receives no response to DHCP
664 * messages sent to the IP address of a known DHCP server, the DHCP
665 * client reverts to using the IP broadcast address.
666 */
667
668static int raw_bcast_from_client_config_ifindex(struct dhcp_packet *packet)
669{
670 return udhcp_send_raw_packet(packet,
671 /*src*/ INADDR_ANY, CLIENT_PORT,
672 /*dst*/ INADDR_BROADCAST, SERVER_PORT, MAC_BCAST_ADDR,
673 client_config.ifindex);
674}
675
676/* Broadcast a DHCP discover packet to the network, with an optionally requested IP */
677/* NOINLINE: limit stack usage in caller */
678static NOINLINE int send_discover(uint32_t xid, uint32_t requested)
679{
680 struct dhcp_packet packet;
681
682 /* Fill in: op, htype, hlen, cookie, chaddr fields,
683 * random xid field (we override it below),
684 * client-id option (unless -C), message type option:
685 */
686 init_packet(&packet, DHCPDISCOVER);
687
688 packet.xid = xid;
689 if (requested)
690 udhcp_add_simple_option(&packet, DHCP_REQUESTED_IP, requested);
691
692 /* Add options: maxsize,
693 * optionally: hostname, fqdn, vendorclass,
694 * "param req" option according to -O, options specified with -x
695 */
696 add_client_options(&packet);
697
698 bb_info_msg("Sending discover...");
699 return raw_bcast_from_client_config_ifindex(&packet);
700}
701
702/* Broadcast a DHCP request message */
703/* RFC 2131 3.1 paragraph 3:
704 * "The client _broadcasts_ a DHCPREQUEST message..."
705 */
706/* NOINLINE: limit stack usage in caller */
707static NOINLINE int send_select(uint32_t xid, uint32_t server, uint32_t requested)
708{
709 struct dhcp_packet packet;
710 struct in_addr addr;
711
712/*
713 * RFC 2131 4.3.2 DHCPREQUEST message
714 * ...
715 * If the DHCPREQUEST message contains a 'server identifier'
716 * option, the message is in response to a DHCPOFFER message.
717 * Otherwise, the message is a request to verify or extend an
718 * existing lease. If the client uses a 'client identifier'
719 * in a DHCPREQUEST message, it MUST use that same 'client identifier'
720 * in all subsequent messages. If the client included a list
721 * of requested parameters in a DHCPDISCOVER message, it MUST
722 * include that list in all subsequent messages.
723 */
724 /* Fill in: op, htype, hlen, cookie, chaddr fields,
725 * random xid field (we override it below),
726 * client-id option (unless -C), message type option:
727 */
728 init_packet(&packet, DHCPREQUEST);
729
730 packet.xid = xid;
731 udhcp_add_simple_option(&packet, DHCP_REQUESTED_IP, requested);
732
733 udhcp_add_simple_option(&packet, DHCP_SERVER_ID, server);
734
735 /* Add options: maxsize,
736 * optionally: hostname, fqdn, vendorclass,
737 * "param req" option according to -O, and options specified with -x
738 */
739 add_client_options(&packet);
740
741 addr.s_addr = requested;
742 bb_info_msg("Sending select for %s...", inet_ntoa(addr));
743 return raw_bcast_from_client_config_ifindex(&packet);
744}
745
746/* Unicast or broadcast a DHCP renew message */
747/* NOINLINE: limit stack usage in caller */
748static NOINLINE int send_renew(uint32_t xid, uint32_t server, uint32_t ciaddr)
749{
750 struct dhcp_packet packet;
751
752/*
753 * RFC 2131 4.3.2 DHCPREQUEST message
754 * ...
755 * DHCPREQUEST generated during RENEWING state:
756 *
757 * 'server identifier' MUST NOT be filled in, 'requested IP address'
758 * option MUST NOT be filled in, 'ciaddr' MUST be filled in with
759 * client's IP address. In this situation, the client is completely
760 * configured, and is trying to extend its lease. This message will
761 * be unicast, so no relay agents will be involved in its
762 * transmission. Because 'giaddr' is therefore not filled in, the
763 * DHCP server will trust the value in 'ciaddr', and use it when
764 * replying to the client.
765 */
766 /* Fill in: op, htype, hlen, cookie, chaddr fields,
767 * random xid field (we override it below),
768 * client-id option (unless -C), message type option:
769 */
770 init_packet(&packet, DHCPREQUEST);
771
772 packet.xid = xid;
773 packet.ciaddr = ciaddr;
774
775 /* Add options: maxsize,
776 * optionally: hostname, fqdn, vendorclass,
777 * "param req" option according to -O, and options specified with -x
778 */
779 add_client_options(&packet);
780
781 bb_info_msg("Sending renew...");
782 if (server)
783 return udhcp_send_kernel_packet(&packet,
784 ciaddr, CLIENT_PORT,
785 server, SERVER_PORT);
786 return raw_bcast_from_client_config_ifindex(&packet);
787}
788
789#if ENABLE_FEATURE_UDHCPC_ARPING
790/* Broadcast a DHCP decline message */
791/* NOINLINE: limit stack usage in caller */
792static NOINLINE int send_decline(/*uint32_t xid,*/ uint32_t server, uint32_t requested)
793{
794 struct dhcp_packet packet;
795
796 /* Fill in: op, htype, hlen, cookie, chaddr, random xid fields,
797 * client-id option (unless -C), message type option:
798 */
799 init_packet(&packet, DHCPDECLINE);
800
801#if 0
802 /* RFC 2131 says DHCPDECLINE's xid is randomly selected by client,
803 * but in case the server is buggy and wants DHCPDECLINE's xid
804 * to match the xid which started entire handshake,
805 * we use the same xid we used in initial DHCPDISCOVER:
806 */
807 packet.xid = xid;
808#endif
809 /* DHCPDECLINE uses "requested ip", not ciaddr, to store offered IP */
810 udhcp_add_simple_option(&packet, DHCP_REQUESTED_IP, requested);
811
812 udhcp_add_simple_option(&packet, DHCP_SERVER_ID, server);
813
814 bb_info_msg("Sending decline...");
815 return raw_bcast_from_client_config_ifindex(&packet);
816}
817#endif
818
819/* Unicast a DHCP release message */
820static int send_release(uint32_t server, uint32_t ciaddr)
821{
822 struct dhcp_packet packet;
823
824 /* Fill in: op, htype, hlen, cookie, chaddr, random xid fields,
825 * client-id option (unless -C), message type option:
826 */
827 init_packet(&packet, DHCPRELEASE);
828
829 /* DHCPRELEASE uses ciaddr, not "requested ip", to store IP being released */
830 packet.ciaddr = ciaddr;
831
832 udhcp_add_simple_option(&packet, DHCP_SERVER_ID, server);
833
834 bb_info_msg("Sending release...");
835 return udhcp_send_kernel_packet(&packet, ciaddr, CLIENT_PORT, server, SERVER_PORT);
836}
837
838/* Returns -1 on errors that are fatal for the socket, -2 for those that aren't */
839/* NOINLINE: limit stack usage in caller */
840static NOINLINE int udhcp_recv_raw_packet(struct dhcp_packet *dhcp_pkt, int fd)
841{
842 int bytes;
843 struct ip_udp_dhcp_packet packet;
844 uint16_t check;
845#ifdef PACKET_AUXDATA
846 unsigned char cmsgbuf[CMSG_LEN(sizeof(struct tpacket_auxdata))];
847 struct cmsghdr *cmsg;
848#endif
849 struct iovec iov;
850 struct msghdr msg;
851
852#ifdef PACKET_AUXDATA
853 /* used to use just safe_read(fd, &packet, sizeof(packet))
854 * but we need to check for TP_STATUS_CSUMNOTREADY :(
855 */
856 iov.iov_base = &packet;
857 iov.iov_len = sizeof(packet);
858 memset(&msg, 0, sizeof(msg));
859 msg.msg_iov = &iov;
860 msg.msg_iovlen = 1;
861 msg.msg_control = cmsgbuf;
862 msg.msg_controllen = sizeof(cmsgbuf);
863 for (;;) {
864 bytes = recvmsg(fd, &msg, 0);
865 if (bytes < 0) {
866 if (errno == EINTR)
867 continue;
868 log1("Packet read error, ignoring");
869 /* NB: possible down interface, etc. Caller should pause. */
870 return bytes; /* returns -1 */
871 }
872 break;
873 }
874#else
875 memset(&packet, 0, sizeof(packet));
876 bytes = safe_read(fd, &packet, sizeof(packet));
877 if (bytes < 0) {
878 log1("Packet read error, ignoring");
879 /* NB: possible down interface, etc. Caller should pause. */
880 return bytes; /* returns -1 */
881 }
882#endif
883
884 if (bytes < (int) (sizeof(packet.ip) + sizeof(packet.udp))) {
885 log1("Packet is too short, ignoring");
886 return -2;
887 }
888
889 if (bytes < ntohs(packet.ip.tot_len)) {
890 /* packet is bigger than sizeof(packet), we did partial read */
891 log1("Oversized packet, ignoring");
892 return -2;
893 }
894
895 /* ignore any extra garbage bytes */
896 bytes = ntohs(packet.ip.tot_len);
897
898 /* make sure its the right packet for us, and that it passes sanity checks */
899 if (packet.ip.protocol != IPPROTO_UDP
900 || packet.ip.version != IPVERSION
901 || packet.ip.ihl != (sizeof(packet.ip) >> 2)
902 || packet.udp.dest != htons(CLIENT_PORT)
903 /* || bytes > (int) sizeof(packet) - can't happen */
904 || ntohs(packet.udp.len) != (uint16_t)(bytes - sizeof(packet.ip))
905 ) {
906 log1("Unrelated/bogus packet, ignoring");
907 return -2;
908 }
909
910 /* verify IP checksum */
911 check = packet.ip.check;
912 packet.ip.check = 0;
913 if (check != inet_cksum((uint16_t *)&packet.ip, sizeof(packet.ip))) {
914 log1("Bad IP header checksum, ignoring");
915 return -2;
916 }
917
918#ifdef PACKET_AUXDATA
919 for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
920 if (cmsg->cmsg_level == SOL_PACKET
921 && cmsg->cmsg_type == PACKET_AUXDATA
922 ) {
923 /* some VMs don't checksum UDP and TCP data
924 * they send to the same physical machine,
925 * here we detect this case:
926 */
927 struct tpacket_auxdata *aux = (void *)CMSG_DATA(cmsg);
928 if (aux->tp_status & TP_STATUS_CSUMNOTREADY)
929 goto skip_udp_sum_check;
930 }
931 }
932#endif
933
934 /* verify UDP checksum. IP header has to be modified for this */
935 memset(&packet.ip, 0, offsetof(struct iphdr, protocol));
936 /* ip.xx fields which are not memset: protocol, check, saddr, daddr */
937 packet.ip.tot_len = packet.udp.len; /* yes, this is needed */
938 check = packet.udp.check;
939 packet.udp.check = 0;
940 if (check && check != inet_cksum((uint16_t *)&packet, bytes)) {
941 log1("Packet with bad UDP checksum received, ignoring");
942 return -2;
943 }
944#ifdef PACKET_AUXDATA
945 skip_udp_sum_check:
946#endif
947
948 if (packet.data.cookie != htonl(DHCP_MAGIC)) {
949 bb_info_msg("Packet with bad magic, ignoring");
950 return -2;
951 }
952
953 log1("Received a packet");
954 udhcp_dump_packet(&packet.data);
955
956 bytes -= sizeof(packet.ip) + sizeof(packet.udp);
957 memcpy(dhcp_pkt, &packet.data, bytes);
958 return bytes;
959}
960
961
962/*** Main ***/
963
964static int sockfd = -1;
965
966#define LISTEN_NONE 0
967#define LISTEN_KERNEL 1
968#define LISTEN_RAW 2
969static smallint listen_mode;
970
971/* initial state: (re)start DHCP negotiation */
972#define INIT_SELECTING 0
973/* discover was sent, DHCPOFFER reply received */
974#define REQUESTING 1
975/* select/renew was sent, DHCPACK reply received */
976#define BOUND 2
977/* half of lease passed, want to renew it by sending unicast renew requests */
978#define RENEWING 3
979/* renew requests were not answered, lease is almost over, send broadcast renew */
980#define REBINDING 4
981/* manually requested renew (SIGUSR1) */
982#define RENEW_REQUESTED 5
983/* release, possibly manually requested (SIGUSR2) */
984#define RELEASED 6
985static smallint state;
986
987static int udhcp_raw_socket(int ifindex)
988{
989 int fd;
990 struct sockaddr_ll sock;
991
992 /*
993 * Comment:
994 *
995 * I've selected not to see LL header, so BPF doesn't see it, too.
996 * The filter may also pass non-IP and non-ARP packets, but we do
997 * a more complete check when receiving the message in userspace.
998 *
999 * and filter shamelessly stolen from:
1000 *
1001 * http://www.flamewarmaster.de/software/dhcpclient/
1002 *
1003 * There are a few other interesting ideas on that page (look under
1004 * "Motivation"). Use of netlink events is most interesting. Think
1005 * of various network servers listening for events and reconfiguring.
1006 * That would obsolete sending HUP signals and/or make use of restarts.
1007 *
1008 * Copyright: 2006, 2007 Stefan Rompf <sux@loplof.de>.
1009 * License: GPL v2.
1010 *
1011 * TODO: make conditional?
1012 */
1013 static const struct sock_filter filter_instr[] = {
1014 /* load 9th byte (protocol) */
1015 BPF_STMT(BPF_LD|BPF_B|BPF_ABS, 9),
1016 /* jump to L1 if it is IPPROTO_UDP, else to L4 */
1017 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, IPPROTO_UDP, 0, 6),
1018 /* L1: load halfword from offset 6 (flags and frag offset) */
1019 BPF_STMT(BPF_LD|BPF_H|BPF_ABS, 6),
1020 /* jump to L4 if any bits in frag offset field are set, else to L2 */
1021 BPF_JUMP(BPF_JMP|BPF_JSET|BPF_K, 0x1fff, 4, 0),
1022 /* L2: skip IP header (load index reg with header len) */
1023 BPF_STMT(BPF_LDX|BPF_B|BPF_MSH, 0),
1024 /* load udp destination port from halfword[header_len + 2] */
1025 BPF_STMT(BPF_LD|BPF_H|BPF_IND, 2),
1026 /* jump to L3 if udp dport is CLIENT_PORT, else to L4 */
1027 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, 68, 0, 1),
1028 /* L3: accept packet */
1029 BPF_STMT(BPF_RET|BPF_K, 0xffffffff),
1030 /* L4: discard packet */
1031 BPF_STMT(BPF_RET|BPF_K, 0),
1032 };
1033 static const struct sock_fprog filter_prog = {
1034 .len = sizeof(filter_instr) / sizeof(filter_instr[0]),
1035 /* casting const away: */
1036 .filter = (struct sock_filter *) filter_instr,
1037 };
1038
1039 log1("Opening raw socket on ifindex %d", ifindex); //log2?
1040
1041 fd = xsocket(PF_PACKET, SOCK_DGRAM, htons(ETH_P_IP));
1042 log1("Got raw socket fd"); //log2?
1043
1044 sock.sll_family = AF_PACKET;
1045 sock.sll_protocol = htons(ETH_P_IP);
1046 sock.sll_ifindex = ifindex;
1047 xbind(fd, (struct sockaddr *) &sock, sizeof(sock));
1048
1049 if (CLIENT_PORT == 68) {
1050 /* Use only if standard port is in use */
1051 /* Ignoring error (kernel may lack support for this) */
1052 if (setsockopt(fd, SOL_SOCKET, SO_ATTACH_FILTER, &filter_prog,
1053 sizeof(filter_prog)) >= 0)
1054 log1("Attached filter to raw socket fd"); // log?
1055 }
1056
1057#ifdef PACKET_AUXDATA
1058 if (setsockopt(fd, SOL_PACKET, PACKET_AUXDATA,
1059 &const_int_1, sizeof(int)) < 0
1060 ) {
1061 if (errno != ENOPROTOOPT)
1062 log1("Can't set PACKET_AUXDATA on raw socket");
1063 }
1064#else
1065 sock.sll_family = AF_PACKET;
1066 sock.sll_protocol = htons(ETH_P_IP);
1067 sock.sll_ifindex = ifindex;
1068 xbind(fd, (struct sockaddr *) &sock, sizeof(sock));
1069#endif
1070
1071 log1("Created raw socket");
1072
1073 return fd;
1074}
1075
1076static void change_listen_mode(int new_mode)
1077{
1078 log1("Entering listen mode: %s",
1079 new_mode != LISTEN_NONE
1080 ? (new_mode == LISTEN_KERNEL ? "kernel" : "raw")
1081 : "none"
1082 );
1083
1084 listen_mode = new_mode;
1085 if (sockfd >= 0) {
1086 close(sockfd);
1087 sockfd = -1;
1088 }
1089 if (new_mode == LISTEN_KERNEL)
1090 sockfd = udhcp_listen_socket(/*INADDR_ANY,*/ CLIENT_PORT, client_config.interface);
1091 else if (new_mode != LISTEN_NONE)
1092 sockfd = udhcp_raw_socket(client_config.ifindex);
1093 /* else LISTEN_NONE: sockfd stays closed */
1094}
1095
1096/* Called only on SIGUSR1 */
1097static void perform_renew(void)
1098{
1099 bb_info_msg("Performing a DHCP renew");
1100 switch (state) {
1101 case BOUND:
1102 change_listen_mode(LISTEN_KERNEL);
1103 case RENEWING:
1104 case REBINDING:
1105 state = RENEW_REQUESTED;
1106 break;
1107 case RENEW_REQUESTED: /* impatient are we? fine, square 1 */
1108 udhcp_run_script(NULL, "deconfig");
1109 case REQUESTING:
1110 case RELEASED:
1111 change_listen_mode(LISTEN_RAW);
1112 state = INIT_SELECTING;
1113 break;
1114 case INIT_SELECTING:
1115 break;
1116 }
1117}
1118
1119static void perform_release(uint32_t server_addr, uint32_t requested_ip)
1120{
1121 char buffer[sizeof("255.255.255.255")];
1122 struct in_addr temp_addr;
1123
1124 /* send release packet */
1125 if (state == BOUND || state == RENEWING || state == REBINDING) {
1126 temp_addr.s_addr = server_addr;
1127 strcpy(buffer, inet_ntoa(temp_addr));
1128 temp_addr.s_addr = requested_ip;
1129 bb_info_msg("Unicasting a release of %s to %s",
1130 inet_ntoa(temp_addr), buffer);
1131 send_release(server_addr, requested_ip); /* unicast */
1132 udhcp_run_script(NULL, "deconfig");
1133 }
1134 bb_info_msg("Entering released state");
1135
1136 change_listen_mode(LISTEN_NONE);
1137 state = RELEASED;
1138}
1139
1140static uint8_t* alloc_dhcp_option(int code, const char *str, int extra)
1141{
1142 uint8_t *storage;
1143 int len = strnlen(str, 255);
1144 storage = xzalloc(len + extra + OPT_DATA);
1145 storage[OPT_CODE] = code;
1146 storage[OPT_LEN] = len + extra;
1147 memcpy(storage + extra + OPT_DATA, str, len);
1148 return storage;
1149}
1150
1151#if BB_MMU
1152static void client_background(void)
1153{
1154 bb_daemonize(0);
1155 logmode &= ~LOGMODE_STDIO;
1156 /* rewrite pidfile, as our pid is different now */
1157 write_pidfile(client_config.pidfile);
1158}
1159#endif
1160
1161//usage:#if defined CONFIG_UDHCP_DEBUG && CONFIG_UDHCP_DEBUG >= 1
1162//usage:# define IF_UDHCP_VERBOSE(...) __VA_ARGS__
1163//usage:#else
1164//usage:# define IF_UDHCP_VERBOSE(...)
1165//usage:#endif
1166//usage:#define udhcpc_trivial_usage
1167//usage: "[-fbnq"IF_UDHCP_VERBOSE("v")"oCRB] [-i IFACE] [-r IP] [-s PROG] [-p PIDFILE]\n"
1168//usage: " [-V VENDOR] [-x OPT:VAL]... [-O OPT]..." IF_FEATURE_UDHCP_PORT(" [-P N]")
1169//usage:#define udhcpc_full_usage "\n"
1170//usage: IF_LONG_OPTS(
1171//usage: "\n -i,--interface IFACE Interface to use (default eth0)"
1172//usage: "\n -p,--pidfile FILE Create pidfile"
1173//usage: "\n -s,--script PROG Run PROG at DHCP events (default "CONFIG_UDHCPC_DEFAULT_SCRIPT")"
1174//usage: "\n -B,--broadcast Request broadcast replies"
1175//usage: "\n -t,--retries N Send up to N discover packets"
1176//usage: "\n -T,--timeout N Pause between packets (default 3 seconds)"
1177//usage: "\n -A,--tryagain N Wait N seconds after failure (default 20)"
1178//usage: "\n -f,--foreground Run in foreground"
1179//usage: USE_FOR_MMU(
1180//usage: "\n -b,--background Background if lease is not obtained"
1181//usage: )
1182//usage: "\n -n,--now Exit if lease is not obtained"
1183//usage: "\n -q,--quit Exit after obtaining lease"
1184//usage: "\n -R,--release Release IP on exit"
1185//usage: "\n -S,--syslog Log to syslog too"
1186//usage: IF_FEATURE_UDHCP_PORT(
1187//usage: "\n -P,--client-port N Use port N (default 68)"
1188//usage: )
1189//usage: IF_FEATURE_UDHCPC_ARPING(
1190//usage: "\n -a,--arping Use arping to validate offered address"
1191//usage: )
1192//usage: "\n -O,--request-option OPT Request option OPT from server (cumulative)"
1193//usage: "\n -o,--no-default-options Don't request any options (unless -O is given)"
1194//usage: "\n -r,--request IP Request this IP address"
1195//usage: "\n -x OPT:VAL Include option OPT in sent packets (cumulative)"
1196//usage: "\n Examples of string, numeric, and hex byte opts:"
1197//usage: "\n -x hostname:bbox - option 12"
1198//usage: "\n -x lease:3600 - option 51 (lease time)"
1199//usage: "\n -x 0x3d:0100BEEFC0FFEE - option 61 (client id)"
1200//usage: "\n -F,--fqdn NAME Ask server to update DNS mapping for NAME"
1201//usage: "\n -V,--vendorclass VENDOR Vendor identifier (default 'udhcp VERSION')"
1202//usage: "\n -C,--clientid-none Don't send MAC as client identifier"
1203//usage: IF_UDHCP_VERBOSE(
1204//usage: "\n -v Verbose"
1205//usage: )
1206//usage: )
1207//usage: IF_NOT_LONG_OPTS(
1208//usage: "\n -i IFACE Interface to use (default eth0)"
1209//usage: "\n -p FILE Create pidfile"
1210//usage: "\n -s PROG Run PROG at DHCP events (default "CONFIG_UDHCPC_DEFAULT_SCRIPT")"
1211//usage: "\n -B Request broadcast replies"
1212//usage: "\n -t N Send up to N discover packets"
1213//usage: "\n -T N Pause between packets (default 3 seconds)"
1214//usage: "\n -A N Wait N seconds (default 20) after failure"
1215//usage: "\n -f Run in foreground"
1216//usage: USE_FOR_MMU(
1217//usage: "\n -b Background if lease is not obtained"
1218//usage: )
1219//usage: "\n -n Exit if lease is not obtained"
1220//usage: "\n -q Exit after obtaining lease"
1221//usage: "\n -R Release IP on exit"
1222//usage: "\n -S Log to syslog too"
1223//usage: IF_FEATURE_UDHCP_PORT(
1224//usage: "\n -P N Use port N (default 68)"
1225//usage: )
1226//usage: IF_FEATURE_UDHCPC_ARPING(
1227//usage: "\n -a Use arping to validate offered address"
1228//usage: )
1229//usage: "\n -O OPT Request option OPT from server (cumulative)"
1230//usage: "\n -o Don't request any options (unless -O is given)"
1231//usage: "\n -r IP Request this IP address"
1232//usage: "\n -x OPT:VAL Include option OPT in sent packets (cumulative)"
1233//usage: "\n Examples of string, numeric, and hex byte opts:"
1234//usage: "\n -x hostname:bbox - option 12"
1235//usage: "\n -x lease:3600 - option 51 (lease time)"
1236//usage: "\n -x 0x3d:0100BEEFC0FFEE - option 61 (client id)"
1237//usage: "\n -F NAME Ask server to update DNS mapping for NAME"
1238//usage: "\n -V VENDOR Vendor identifier (default 'udhcp VERSION')"
1239//usage: "\n -C Don't send MAC as client identifier"
1240//usage: IF_UDHCP_VERBOSE(
1241//usage: "\n -v Verbose"
1242//usage: )
1243//usage: )
1244//usage: "\nSignals:"
1245//usage: "\n USR1 Renew lease"
1246//usage: "\n USR2 Release lease"
1247
1248
1249int udhcpc_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
1250int udhcpc_main(int argc UNUSED_PARAM, char **argv)
1251{
1252 uint8_t *temp, *message;
1253 const char *str_V, *str_h, *str_F, *str_r;
1254 IF_FEATURE_UDHCP_PORT(char *str_P;)
1255 void *clientid_mac_ptr;
1256 llist_t *list_O = NULL;
1257 llist_t *list_x = NULL;
1258 int tryagain_timeout = 20;
1259 int discover_timeout = 3;
1260 int discover_retries = 3;
1261 uint32_t server_addr = server_addr; /* for compiler */
1262 uint32_t requested_ip = 0;
1263 uint32_t xid = xid; /* for compiler */
1264 int packet_num;
1265 int timeout; /* must be signed */
1266 unsigned already_waited_sec;
1267 unsigned opt;
1268 int max_fd;
1269 int retval;
1270 fd_set rfds;
1271
1272 /* Default options */
1273 IF_FEATURE_UDHCP_PORT(SERVER_PORT = 67;)
1274 IF_FEATURE_UDHCP_PORT(CLIENT_PORT = 68;)
1275 client_config.interface = "eth0";
1276 client_config.script = CONFIG_UDHCPC_DEFAULT_SCRIPT;
1277 str_V = "udhcp "BB_VER;
1278
1279 /* Parse command line */
1280 /* O,x: list; -T,-t,-A take numeric param */
1281 opt_complementary = "O::x::T+:t+:A+" IF_UDHCP_VERBOSE(":vv") ;
1282 IF_LONG_OPTS(applet_long_options = udhcpc_longopts;)
1283 opt = getopt32(argv, "CV:H:h:F:i:np:qRr:s:T:t:SA:O:ox:fB"
1284 USE_FOR_MMU("b")
1285 IF_FEATURE_UDHCPC_ARPING("a")
1286 IF_FEATURE_UDHCP_PORT("P:")
1287 "v"
1288 , &str_V, &str_h, &str_h, &str_F
1289 , &client_config.interface, &client_config.pidfile, &str_r /* i,p */
1290 , &client_config.script /* s */
1291 , &discover_timeout, &discover_retries, &tryagain_timeout /* T,t,A */
1292 , &list_O
1293 , &list_x
1294 IF_FEATURE_UDHCP_PORT(, &str_P)
1295 IF_UDHCP_VERBOSE(, &dhcp_verbose)
1296 );
1297 if (opt & (OPT_h|OPT_H)) {
1298 //msg added 2011-11
1299 bb_error_msg("option -h NAME is deprecated, use -x hostname:NAME");
1300 client_config.hostname = alloc_dhcp_option(DHCP_HOST_NAME, str_h, 0);
1301 }
1302 if (opt & OPT_F) {
1303 /* FQDN option format: [0x51][len][flags][0][0]<fqdn> */
1304 client_config.fqdn = alloc_dhcp_option(DHCP_FQDN, str_F, 3);
1305 /* Flag bits: 0000NEOS
1306 * S: 1 = Client requests server to update A RR in DNS as well as PTR
1307 * O: 1 = Server indicates to client that DNS has been updated regardless
1308 * E: 1 = Name is in DNS format, i.e. <4>host<6>domain<3>com<0>,
1309 * not "host.domain.com". Format 0 is obsolete.
1310 * N: 1 = Client requests server to not update DNS (S must be 0 then)
1311 * Two [0] bytes which follow are deprecated and must be 0.
1312 */
1313 client_config.fqdn[OPT_DATA + 0] = 0x1;
1314 /*client_config.fqdn[OPT_DATA + 1] = 0; - xzalloc did it */
1315 /*client_config.fqdn[OPT_DATA + 2] = 0; */
1316 }
1317 if (opt & OPT_r)
1318 requested_ip = inet_addr(str_r);
1319#if ENABLE_FEATURE_UDHCP_PORT
1320 if (opt & OPT_P) {
1321 CLIENT_PORT = xatou16(str_P);
1322 SERVER_PORT = CLIENT_PORT - 1;
1323 }
1324#endif
1325 while (list_O) {
1326 char *optstr = llist_pop(&list_O);
1327 unsigned n = bb_strtou(optstr, NULL, 0);
1328 if (errno || n > 254) {
1329 n = udhcp_option_idx(optstr);
1330 n = dhcp_optflags[n].code;
1331 }
1332 client_config.opt_mask[n >> 3] |= 1 << (n & 7);
1333 }
1334 if (!(opt & OPT_o)) {
1335 unsigned i, n;
1336 for (i = 0; (n = dhcp_optflags[i].code) != 0; i++) {
1337 if (dhcp_optflags[i].flags & OPTION_REQ) {
1338 client_config.opt_mask[n >> 3] |= 1 << (n & 7);
1339 }
1340 }
1341 }
1342 while (list_x) {
1343 char *optstr = llist_pop(&list_x);
1344 char *colon = strchr(optstr, ':');
1345 if (colon)
1346 *colon = ' ';
1347 /* now it looks similar to udhcpd's config file line:
1348 * "optname optval", using the common routine: */
1349 udhcp_str2optset(optstr, &client_config.options);
1350 }
1351
1352 if (udhcp_read_interface(client_config.interface,
1353 &client_config.ifindex,
1354 NULL,
1355 client_config.client_mac)
1356 ) {
1357 return 1;
1358 }
1359
1360 clientid_mac_ptr = NULL;
1361 if (!(opt & OPT_C) && !udhcp_find_option(client_config.options, DHCP_CLIENT_ID)) {
1362 /* not suppressed and not set, set the default client ID */
1363 client_config.clientid = alloc_dhcp_option(DHCP_CLIENT_ID, "", 7);
1364 client_config.clientid[OPT_DATA] = 1; /* type: ethernet */
1365 clientid_mac_ptr = client_config.clientid + OPT_DATA+1;
1366 memcpy(clientid_mac_ptr, client_config.client_mac, 6);
1367 }
1368 if (str_V[0] != '\0') {
1369 // can drop -V, str_V, client_config.vendorclass,
1370 // but need to add "vendor" to the list of recognized
1371 // string opts for this to work;
1372 // and need to tweak add_client_options() too...
1373 // ...so the question is, should we?
1374 //bb_error_msg("option -V VENDOR is deprecated, use -x vendor:VENDOR");
1375 client_config.vendorclass = alloc_dhcp_option(DHCP_VENDOR, str_V, 0);
1376 }
1377
1378#if !BB_MMU
1379 /* on NOMMU reexec (i.e., background) early */
1380 if (!(opt & OPT_f)) {
1381 bb_daemonize_or_rexec(0 /* flags */, argv);
1382 logmode = LOGMODE_NONE;
1383 }
1384#endif
1385 if (opt & OPT_S) {
1386 openlog(applet_name, LOG_PID, LOG_DAEMON);
1387 logmode |= LOGMODE_SYSLOG;
1388 }
1389
1390 /* Make sure fd 0,1,2 are open */
1391 bb_sanitize_stdio();
1392 /* Equivalent of doing a fflush after every \n */
1393 setlinebuf(stdout);
1394 /* Create pidfile */
1395 write_pidfile(client_config.pidfile);
1396 /* Goes to stdout (unless NOMMU) and possibly syslog */
1397 bb_info_msg("%s (v"BB_VER") started", applet_name);
1398 /* Set up the signal pipe */
1399 udhcp_sp_setup();
1400 /* We want random_xid to be random... */
1401 srand(monotonic_us());
1402
1403 state = INIT_SELECTING;
1404 udhcp_run_script(NULL, "deconfig");
1405 change_listen_mode(LISTEN_RAW);
1406 packet_num = 0;
1407 timeout = 0;
1408 already_waited_sec = 0;
1409
1410 /* Main event loop. select() waits on signal pipe and possibly
1411 * on sockfd.
1412 * "continue" statements in code below jump to the top of the loop.
1413 */
1414 for (;;) {
1415 struct timeval tv;
1416 struct dhcp_packet packet;
1417 /* silence "uninitialized!" warning */
1418 unsigned timestamp_before_wait = timestamp_before_wait;
1419
1420 //bb_error_msg("sockfd:%d, listen_mode:%d", sockfd, listen_mode);
1421
1422 /* Was opening raw or udp socket here
1423 * if (listen_mode != LISTEN_NONE && sockfd < 0),
1424 * but on fast network renew responses return faster
1425 * than we open sockets. Thus this code is moved
1426 * to change_listen_mode(). Thus we open listen socket
1427 * BEFORE we send renew request (see "case BOUND:"). */
1428
1429 max_fd = udhcp_sp_fd_set(&rfds, sockfd);
1430
1431 tv.tv_sec = timeout - already_waited_sec;
1432 tv.tv_usec = 0;
1433 retval = 0;
1434 /* If we already timed out, fall through with retval = 0, else... */
1435 if ((int)tv.tv_sec > 0) {
1436 log1("Waiting on select %u seconds", (int)tv.tv_sec);
1437 timestamp_before_wait = (unsigned)monotonic_sec();
1438 retval = select(max_fd + 1, &rfds, NULL, NULL, &tv);
1439 if (retval < 0) {
1440 /* EINTR? A signal was caught, don't panic */
1441 if (errno == EINTR) {
1442 already_waited_sec += (unsigned)monotonic_sec() - timestamp_before_wait;
1443 continue;
1444 }
1445 /* Else: an error occured, panic! */
1446 bb_perror_msg_and_die("select");
1447 }
1448 }
1449
1450 /* If timeout dropped to zero, time to become active:
1451 * resend discover/renew/whatever
1452 */
1453 if (retval == 0) {
1454 /* When running on a bridge, the ifindex may have changed
1455 * (e.g. if member interfaces were added/removed
1456 * or if the status of the bridge changed).
1457 * Refresh ifindex and client_mac:
1458 */
1459 if (udhcp_read_interface(client_config.interface,
1460 &client_config.ifindex,
1461 NULL,
1462 client_config.client_mac)
1463 ) {
1464 goto ret0; /* iface is gone? */
1465 }
1466 if (clientid_mac_ptr)
1467 memcpy(clientid_mac_ptr, client_config.client_mac, 6);
1468
1469 /* We will restart the wait in any case */
1470 already_waited_sec = 0;
1471
1472 switch (state) {
1473 case INIT_SELECTING:
1474 if (!discover_retries || packet_num < discover_retries) {
1475 if (packet_num == 0)
1476 xid = random_xid();
1477 /* broadcast */
1478 send_discover(xid, requested_ip);
1479 timeout = discover_timeout;
1480 packet_num++;
1481 continue;
1482 }
1483 leasefail:
1484 udhcp_run_script(NULL, "leasefail");
1485#if BB_MMU /* -b is not supported on NOMMU */
1486 if (opt & OPT_b) { /* background if no lease */
1487 bb_info_msg("No lease, forking to background");
1488 client_background();
1489 /* do not background again! */
1490 opt = ((opt & ~OPT_b) | OPT_f);
1491 } else
1492#endif
1493 if (opt & OPT_n) { /* abort if no lease */
1494 bb_info_msg("No lease, failing");
1495 retval = 1;
1496 goto ret;
1497 }
1498 /* wait before trying again */
1499 timeout = tryagain_timeout;
1500 packet_num = 0;
1501 continue;
1502 case REQUESTING:
1503 if (!discover_retries || packet_num < discover_retries) {
1504 /* send broadcast select packet */
1505 send_select(xid, server_addr, requested_ip);
1506 timeout = discover_timeout;
1507 packet_num++;
1508 continue;
1509 }
1510 /* Timed out, go back to init state.
1511 * "discover...select...discover..." loops
1512 * were seen in the wild. Treat them similarly
1513 * to "no response to discover" case */
1514 change_listen_mode(LISTEN_RAW);
1515 state = INIT_SELECTING;
1516 goto leasefail;
1517 case BOUND:
1518 /* 1/2 lease passed, enter renewing state */
1519 state = RENEWING;
1520 client_config.first_secs = 0; /* make secs field count from 0 */
1521 change_listen_mode(LISTEN_KERNEL);
1522 log1("Entering renew state");
1523 /* fall right through */
1524 case RENEW_REQUESTED: /* manual (SIGUSR1) renew */
1525 case_RENEW_REQUESTED:
1526 case RENEWING:
1527 if (timeout > 60) {
1528 /* send an unicast renew request */
1529 /* Sometimes observed to fail (EADDRNOTAVAIL) to bind
1530 * a new UDP socket for sending inside send_renew.
1531 * I hazard to guess existing listening socket
1532 * is somehow conflicting with it, but why is it
1533 * not deterministic then?! Strange.
1534 * Anyway, it does recover by eventually failing through
1535 * into INIT_SELECTING state.
1536 */
1537 send_renew(xid, server_addr, requested_ip);
1538 timeout >>= 1;
1539 continue;
1540 }
1541 /* Timed out, enter rebinding state */
1542 log1("Entering rebinding state");
1543 state = REBINDING;
1544 /* fall right through */
1545 case REBINDING:
1546 /* Switch to bcast receive */
1547 change_listen_mode(LISTEN_RAW);
1548 /* Lease is *really* about to run out,
1549 * try to find DHCP server using broadcast */
1550 if (timeout > 0) {
1551 /* send a broadcast renew request */
1552 send_renew(xid, 0 /*INADDR_ANY*/, requested_ip);
1553 timeout >>= 1;
1554 continue;
1555 }
1556 /* Timed out, enter init state */
1557 bb_info_msg("Lease lost, entering init state");
1558 udhcp_run_script(NULL, "deconfig");
1559 state = INIT_SELECTING;
1560 client_config.first_secs = 0; /* make secs field count from 0 */
1561 /*timeout = 0; - already is */
1562 packet_num = 0;
1563 continue;
1564 /* case RELEASED: */
1565 }
1566 /* yah, I know, *you* say it would never happen */
1567 timeout = INT_MAX;
1568 continue; /* back to main loop */
1569 } /* if select timed out */
1570
1571 /* select() didn't timeout, something happened */
1572
1573 /* Is it a signal? */
1574 /* note: udhcp_sp_read checks FD_ISSET before reading */
1575 switch (udhcp_sp_read(&rfds)) {
1576 case SIGUSR1:
1577 client_config.first_secs = 0; /* make secs field count from 0 */
1578 already_waited_sec = 0;
1579 perform_renew();
1580 if (state == RENEW_REQUESTED) {
1581 /* We might be either on the same network
1582 * (in which case renew might work),
1583 * or we might be on a completely different one
1584 * (in which case renew won't ever succeed).
1585 * For the second case, must make sure timeout
1586 * is not too big, or else we can send
1587 * futile renew requests for hours.
1588 * (Ab)use -A TIMEOUT value (usually 20 sec)
1589 * as a cap on the timeout.
1590 */
1591 if (timeout > tryagain_timeout)
1592 timeout = tryagain_timeout;
1593 goto case_RENEW_REQUESTED;
1594 }
1595 /* Start things over */
1596 packet_num = 0;
1597 /* Kill any timeouts, user wants this to hurry along */
1598 timeout = 0;
1599 continue;
1600 case SIGUSR2:
1601 perform_release(server_addr, requested_ip);
1602 timeout = INT_MAX;
1603 continue;
1604 case SIGTERM:
1605 bb_info_msg("Received SIGTERM");
1606 goto ret0;
1607 }
1608
1609 /* Is it a packet? */
1610 if (listen_mode == LISTEN_NONE || !FD_ISSET(sockfd, &rfds))
1611 continue; /* no */
1612
1613 {
1614 int len;
1615
1616 /* A packet is ready, read it */
1617 if (listen_mode == LISTEN_KERNEL)
1618 len = udhcp_recv_kernel_packet(&packet, sockfd);
1619 else
1620 len = udhcp_recv_raw_packet(&packet, sockfd);
1621 if (len == -1) {
1622 /* Error is severe, reopen socket */
1623 bb_info_msg("Read error: %s, reopening socket", strerror(errno));
1624 sleep(discover_timeout); /* 3 seconds by default */
1625 change_listen_mode(listen_mode); /* just close and reopen */
1626 }
1627 /* If this packet will turn out to be unrelated/bogus,
1628 * we will go back and wait for next one.
1629 * Be sure timeout is properly decreased. */
1630 already_waited_sec += (unsigned)monotonic_sec() - timestamp_before_wait;
1631 if (len < 0)
1632 continue;
1633 }
1634
1635 if (packet.xid != xid) {
1636 log1("xid %x (our is %x), ignoring packet",
1637 (unsigned)packet.xid, (unsigned)xid);
1638 continue;
1639 }
1640
1641 /* Ignore packets that aren't for us */
1642 if (packet.hlen != 6
1643 || memcmp(packet.chaddr, client_config.client_mac, 6) != 0
1644 ) {
1645//FIXME: need to also check that last 10 bytes are zero
1646 log1("chaddr does not match, ignoring packet"); // log2?
1647 continue;
1648 }
1649
1650 message = udhcp_get_option(&packet, DHCP_MESSAGE_TYPE);
1651 if (message == NULL) {
1652 bb_error_msg("no message type option, ignoring packet");
1653 continue;
1654 }
1655
1656 switch (state) {
1657 case INIT_SELECTING:
1658 /* Must be a DHCPOFFER */
1659 if (*message == DHCPOFFER) {
1660/* What exactly is server's IP? There are several values.
1661 * Example DHCP offer captured with tchdump:
1662 *
1663 * 10.34.25.254:67 > 10.34.25.202:68 // IP header's src
1664 * BOOTP fields:
1665 * Your-IP 10.34.25.202
1666 * Server-IP 10.34.32.125 // "next server" IP
1667 * Gateway-IP 10.34.25.254 // relay's address (if DHCP relays are in use)
1668 * DHCP options:
1669 * DHCP-Message Option 53, length 1: Offer
1670 * Server-ID Option 54, length 4: 10.34.255.7 // "server ID"
1671 * Default-Gateway Option 3, length 4: 10.34.25.254 // router
1672 *
1673 * We think that real server IP (one to use in renew/release)
1674 * is one in Server-ID option. But I am not 100% sure.
1675 * IP header's src and Gateway-IP (same in this example)
1676 * might work too.
1677 * "Next server" and router are definitely wrong ones to use, though...
1678 */
1679 temp = udhcp_get_option(&packet, DHCP_SERVER_ID);
1680 if (!temp) {
1681 bb_error_msg("no server ID, ignoring packet");
1682 continue;
1683 /* still selecting - this server looks bad */
1684 }
1685 /* it IS unaligned sometimes, don't "optimize" */
1686 move_from_unaligned32(server_addr, temp);
1687 /*xid = packet.xid; - already is */
1688 requested_ip = packet.yiaddr;
1689
1690 /* enter requesting state */
1691 state = REQUESTING;
1692 timeout = 0;
1693 packet_num = 0;
1694 already_waited_sec = 0;
1695 }
1696 continue;
1697 case REQUESTING:
1698 case RENEWING:
1699 case RENEW_REQUESTED:
1700 case REBINDING:
1701 if (*message == DHCPACK) {
1702 uint32_t lease_seconds;
1703 struct in_addr temp_addr;
1704
1705 temp = udhcp_get_option(&packet, DHCP_LEASE_TIME);
1706 if (!temp) {
1707 bb_error_msg("no lease time with ACK, using 1 hour lease");
1708 lease_seconds = 60 * 60;
1709 } else {
1710 /* it IS unaligned sometimes, don't "optimize" */
1711 move_from_unaligned32(lease_seconds, temp);
1712 lease_seconds = ntohl(lease_seconds);
1713 /* paranoia: must not be too small and not prone to overflows */
1714 if (lease_seconds < 0x10)
1715 lease_seconds = 0x10;
1716 if (lease_seconds >= 0x10000000)
1717 lease_seconds = 0x0fffffff;
1718 }
1719#if ENABLE_FEATURE_UDHCPC_ARPING
1720 if (opt & OPT_a) {
1721/* RFC 2131 3.1 paragraph 5:
1722 * "The client receives the DHCPACK message with configuration
1723 * parameters. The client SHOULD perform a final check on the
1724 * parameters (e.g., ARP for allocated network address), and notes
1725 * the duration of the lease specified in the DHCPACK message. At this
1726 * point, the client is configured. If the client detects that the
1727 * address is already in use (e.g., through the use of ARP),
1728 * the client MUST send a DHCPDECLINE message to the server and restarts
1729 * the configuration process..." */
1730 if (!arpping(packet.yiaddr,
1731 NULL,
1732 (uint32_t) 0,
1733 client_config.client_mac,
1734 client_config.interface)
1735 ) {
1736 bb_info_msg("Offered address is in use "
1737 "(got ARP reply), declining");
1738 send_decline(/*xid,*/ server_addr, packet.yiaddr);
1739
1740 if (state != REQUESTING)
1741 udhcp_run_script(NULL, "deconfig");
1742 change_listen_mode(LISTEN_RAW);
1743 state = INIT_SELECTING;
1744 client_config.first_secs = 0; /* make secs field count from 0 */
1745 requested_ip = 0;
1746 timeout = tryagain_timeout;
1747 packet_num = 0;
1748 already_waited_sec = 0;
1749 continue; /* back to main loop */
1750 }
1751 }
1752#endif
1753 /* enter bound state */
1754 timeout = lease_seconds / 2;
1755 temp_addr.s_addr = packet.yiaddr;
1756 bb_info_msg("Lease of %s obtained, lease time %u",
1757 inet_ntoa(temp_addr), (unsigned)lease_seconds);
1758 requested_ip = packet.yiaddr;
1759 udhcp_run_script(&packet, state == REQUESTING ? "bound" : "renew");
1760
1761 state = BOUND;
1762 change_listen_mode(LISTEN_NONE);
1763 if (opt & OPT_q) { /* quit after lease */
1764 goto ret0;
1765 }
1766 /* future renew failures should not exit (JM) */
1767 opt &= ~OPT_n;
1768#if BB_MMU /* NOMMU case backgrounded earlier */
1769 if (!(opt & OPT_f)) {
1770 client_background();
1771 /* do not background again! */
1772 opt = ((opt & ~OPT_b) | OPT_f);
1773 }
1774#endif
1775 /* make future renew packets use different xid */
1776 /* xid = random_xid(); ...but why bother? */
1777 already_waited_sec = 0;
1778 continue; /* back to main loop */
1779 }
1780 if (*message == DHCPNAK) {
1781 /* return to init state */
1782 bb_info_msg("Received DHCP NAK");
1783 udhcp_run_script(&packet, "nak");
1784 if (state != REQUESTING)
1785 udhcp_run_script(NULL, "deconfig");
1786 change_listen_mode(LISTEN_RAW);
1787 sleep(3); /* avoid excessive network traffic */
1788 state = INIT_SELECTING;
1789 client_config.first_secs = 0; /* make secs field count from 0 */
1790 requested_ip = 0;
1791 timeout = 0;
1792 packet_num = 0;
1793 already_waited_sec = 0;
1794 }
1795 continue;
1796 /* case BOUND: - ignore all packets */
1797 /* case RELEASED: - ignore all packets */
1798 }
1799 /* back to main loop */
1800 } /* for (;;) - main loop ends */
1801
1802 ret0:
1803 if (opt & OPT_R) /* release on quit */
1804 perform_release(server_addr, requested_ip);
1805 retval = 0;
1806 ret:
1807 /*if (client_config.pidfile) - remove_pidfile has its own check */
1808 remove_pidfile(client_config.pidfile);
1809 return retval;
1810}
Note: See TracBrowser for help on using the repository browser.