source: MondoRescue/branches/2.2.9/mindi-busybox/networking/udhcp/files.c@ 2142

Last change on this file since 2142 was 1765, checked in by Bruno Cornec, 16 years ago

Update to busybox 1.7.2
File size: 11.3 KB
Line 
1/* vi: set sw=4 ts=4: */
2/*
3 * files.c -- DHCP server file manipulation *
4 * Rewrite by Russ Dill <Russ.Dill@asu.edu> July 2001
5 */
6
7#include <netinet/ether.h>
8
9#include "common.h"
10#include "dhcpd.h"
11#include "options.h"
12
13
14/* on these functions, make sure your datatype matches */
15static int read_ip(const char *line, void *arg)
16{
17 len_and_sockaddr *lsa;
18
19 lsa = host_and_af2sockaddr(line, 0, AF_INET);
20 if (!lsa)
21 return 0;
22 *(uint32_t*)arg = lsa->sin.sin_addr.s_addr;
23 free(lsa);
24 return 1;
25}
26
27static int read_mac(const char *line, void *arg)
28{
29 uint8_t *mac_bytes = arg;
30 struct ether_addr *temp_ether_addr;
31
32 temp_ether_addr = ether_aton(line);
33 if (temp_ether_addr == NULL)
34 return 0;
35 memcpy(mac_bytes, temp_ether_addr, 6);
36 return 1;
37}
38
39
40static int read_str(const char *line, void *arg)
41{
42 char **dest = arg;
43
44 free(*dest);
45 *dest = xstrdup(line);
46 return 1;
47}
48
49
50static int read_u32(const char *line, void *arg)
51{
52 *(uint32_t*)arg = bb_strtou32(line, NULL, 10);
53 return errno == 0;
54}
55
56
57static int read_yn(const char *line, void *arg)
58{
59 char *dest = arg;
60
61 if (!strcasecmp("yes", line)) {
62 *dest = 1;
63 return 1;
64 }
65 if (!strcasecmp("no", line)) {
66 *dest = 0;
67 return 1;
68 }
69 return 0;
70}
71
72
73/* find option 'code' in opt_list */
74struct option_set *find_option(struct option_set *opt_list, char code)
75{
76 while (opt_list && opt_list->data[OPT_CODE] < code)
77 opt_list = opt_list->next;
78
79 if (opt_list && opt_list->data[OPT_CODE] == code)
80 return opt_list;
81 return NULL;
82}
83
84
85/* add an option to the opt_list */
86static void attach_option(struct option_set **opt_list,
87 const struct dhcp_option *option, char *buffer, int length)
88{
89 struct option_set *existing, *new, **curr;
90
91 existing = find_option(*opt_list, option->code);
92 if (!existing) {
93 DEBUG("Attaching option %s to list", option->name);
94
95#if ENABLE_FEATURE_RFC3397
96 if ((option->flags & TYPE_MASK) == OPTION_STR1035)
97 /* reuse buffer and length for RFC1035-formatted string */
98 buffer = dname_enc(NULL, 0, buffer, &length);
99#endif
100
101 /* make a new option */
102 new = xmalloc(sizeof(*new));
103 new->data = xmalloc(length + 2);
104 new->data[OPT_CODE] = option->code;
105 new->data[OPT_LEN] = length;
106 memcpy(new->data + 2, buffer, length);
107
108 curr = opt_list;
109 while (*curr && (*curr)->data[OPT_CODE] < option->code)
110 curr = &(*curr)->next;
111
112 new->next = *curr;
113 *curr = new;
114#if ENABLE_FEATURE_RFC3397
115 if ((option->flags & TYPE_MASK) == OPTION_STR1035 && buffer != NULL)
116 free(buffer);
117#endif
118 return;
119 }
120
121 /* add it to an existing option */
122 DEBUG("Attaching option %s to existing member of list", option->name);
123 if (option->flags & OPTION_LIST) {
124#if ENABLE_FEATURE_RFC3397
125 if ((option->flags & TYPE_MASK) == OPTION_STR1035)
126 /* reuse buffer and length for RFC1035-formatted string */
127 buffer = dname_enc(existing->data + 2,
128 existing->data[OPT_LEN], buffer, &length);
129#endif
130 if (existing->data[OPT_LEN] + length <= 255) {
131 existing->data = xrealloc(existing->data,
132 existing->data[OPT_LEN] + length + 3);
133 if ((option->flags & TYPE_MASK) == OPTION_STRING) {
134 /* ' ' can bring us to 256 - bad */
135 if (existing->data[OPT_LEN] + length >= 255)
136 return;
137 /* add space separator between STRING options in a list */
138 existing->data[existing->data[OPT_LEN] + 2] = ' ';
139 existing->data[OPT_LEN]++;
140 }
141 memcpy(existing->data + existing->data[OPT_LEN] + 2, buffer, length);
142 existing->data[OPT_LEN] += length;
143 } /* else, ignore the data, we could put this in a second option in the future */
144#if ENABLE_FEATURE_RFC3397
145 if ((option->flags & TYPE_MASK) == OPTION_STR1035 && buffer != NULL)
146 free(buffer);
147#endif
148 } /* else, ignore the new data */
149}
150
151
152/* read a dhcp option and add it to opt_list */
153static int read_opt(const char *const_line, void *arg)
154{
155 struct option_set **opt_list = arg;
156 char *opt, *val, *endptr;
157 const struct dhcp_option *option;
158 int retval = 0, length;
159 char buffer[8];
160 char *line;
161 uint16_t *result_u16 = (uint16_t *) buffer;
162 uint32_t *result_u32 = (uint32_t *) buffer;
163
164 /* Cheat, the only const line we'll actually get is "" */
165 line = (char *) const_line;
166 opt = strtok(line, " \t=");
167 if (!opt) return 0;
168
169 option = dhcp_options;
170 while (1) {
171 if (!option->code)
172 return 0;
173 if (!strcasecmp(option->name, opt))
174 break;
175 option++;
176 }
177
178 do {
179 val = strtok(NULL, ", \t");
180 if (!val) break;
181 length = option_lengths[option->flags & TYPE_MASK];
182 retval = 0;
183 opt = buffer; /* new meaning for variable opt */
184 switch (option->flags & TYPE_MASK) {
185 case OPTION_IP:
186 retval = read_ip(val, buffer);
187 break;
188 case OPTION_IP_PAIR:
189 retval = read_ip(val, buffer);
190 val = strtok(NULL, ", \t/-");
191 if (!val)
192 retval = 0;
193 if (retval)
194 retval = read_ip(val, buffer + 4);
195 break;
196 case OPTION_STRING:
197#if ENABLE_FEATURE_RFC3397
198 case OPTION_STR1035:
199#endif
200 length = strlen(val);
201 if (length > 0) {
202 if (length > 254) length = 254;
203 opt = val;
204 retval = 1;
205 }
206 break;
207 case OPTION_BOOLEAN:
208 retval = read_yn(val, buffer);
209 break;
210 case OPTION_U8:
211 buffer[0] = strtoul(val, &endptr, 0);
212 retval = (endptr[0] == '\0');
213 break;
214 /* htonX are macros in older libc's, using temp var
215 * in code below for safety */
216 /* TODO: use bb_strtoX? */
217 case OPTION_U16: {
218 unsigned long tmp = strtoul(val, &endptr, 0);
219 *result_u16 = htons(tmp);
220 retval = (endptr[0] == '\0' /*&& tmp < 0x10000*/);
221 break;
222 }
223 case OPTION_S16: {
224 long tmp = strtol(val, &endptr, 0);
225 *result_u16 = htons(tmp);
226 retval = (endptr[0] == '\0');
227 break;
228 }
229 case OPTION_U32: {
230 unsigned long tmp = strtoul(val, &endptr, 0);
231 *result_u32 = htonl(tmp);
232 retval = (endptr[0] == '\0');
233 break;
234 }
235 case OPTION_S32: {
236 long tmp = strtol(val, &endptr, 0);
237 *result_u32 = htonl(tmp);
238 retval = (endptr[0] == '\0');
239 break;
240 }
241 default:
242 break;
243 }
244 if (retval)
245 attach_option(opt_list, option, opt, length);
246 } while (retval && option->flags & OPTION_LIST);
247 return retval;
248}
249
250static int read_staticlease(const char *const_line, void *arg)
251{
252 char *line;
253 char *mac_string;
254 char *ip_string;
255 uint8_t *mac_bytes;
256 uint32_t *ip;
257
258 /* Allocate memory for addresses */
259 mac_bytes = xmalloc(sizeof(unsigned char) * 8);
260 ip = xmalloc(sizeof(uint32_t));
261
262 /* Read mac */
263 line = (char *) const_line;
264 mac_string = strtok(line, " \t");
265 read_mac(mac_string, mac_bytes);
266
267 /* Read ip */
268 ip_string = strtok(NULL, " \t");
269 read_ip(ip_string, ip);
270
271 addStaticLease(arg, mac_bytes, ip);
272
273 if (ENABLE_FEATURE_UDHCP_DEBUG) printStaticLeases(arg);
274
275 return 1;
276}
277
278
279struct config_keyword {
280 const char *keyword;
281 int (*handler)(const char *line, void *var);
282 void *var;
283 const char *def;
284};
285
286static const struct config_keyword keywords[] = {
287 /* keyword handler variable address default */
288 {"start", read_ip, &(server_config.start_ip), "192.168.0.20"},
289 {"end", read_ip, &(server_config.end_ip), "192.168.0.254"},
290 {"interface", read_str, &(server_config.interface), "eth0"},
291 {"option", read_opt, &(server_config.options), ""},
292 {"opt", read_opt, &(server_config.options), ""},
293 /* Avoid "max_leases value not sane" warning by setting default
294 * to default_end_ip - default_start_ip + 1: */
295 {"max_leases", read_u32, &(server_config.max_leases), "235"},
296 {"remaining", read_yn, &(server_config.remaining), "yes"},
297 {"auto_time", read_u32, &(server_config.auto_time), "7200"},
298 {"decline_time", read_u32, &(server_config.decline_time), "3600"},
299 {"conflict_time",read_u32, &(server_config.conflict_time),"3600"},
300 {"offer_time", read_u32, &(server_config.offer_time), "60"},
301 {"min_lease", read_u32, &(server_config.min_lease), "60"},
302 {"lease_file", read_str, &(server_config.lease_file), LEASES_FILE},
303 {"pidfile", read_str, &(server_config.pidfile), "/var/run/udhcpd.pid"},
304 {"notify_file", read_str, &(server_config.notify_file), ""},
305 {"siaddr", read_ip, &(server_config.siaddr), "0.0.0.0"},
306 {"sname", read_str, &(server_config.sname), ""},
307 {"boot_file", read_str, &(server_config.boot_file), ""},
308 {"static_lease", read_staticlease, &(server_config.static_leases), ""},
309 /* ADDME: static lease */
310};
311
312
313/*
314 * Domain names may have 254 chars, and string options can be 254
315 * chars long. However, 80 bytes will be enough for most, and won't
316 * hog up memory. If you have a special application, change it
317 */
318#define READ_CONFIG_BUF_SIZE 80
319
320int read_config(const char *file)
321{
322 FILE *in;
323 char buffer[READ_CONFIG_BUF_SIZE], *token, *line;
324 int i, lm = 0;
325
326 for (i = 0; i < ARRAY_SIZE(keywords); i++)
327 if (keywords[i].def[0])
328 keywords[i].handler(keywords[i].def, keywords[i].var);
329
330 in = fopen_or_warn(file, "r");
331 if (!in) {
332 return 0;
333 }
334
335 while (fgets(buffer, READ_CONFIG_BUF_SIZE, in)) {
336 char debug_orig[READ_CONFIG_BUF_SIZE];
337 char *p;
338
339 lm++;
340 p = strchr(buffer, '\n');
341 if (p) *p = '\0';
342 if (ENABLE_FEATURE_UDHCP_DEBUG) strcpy(debug_orig, buffer);
343 p = strchr(buffer, '#');
344 if (p) *p = '\0';
345
346 if (!(token = strtok(buffer, " \t"))) continue;
347 if (!(line = strtok(NULL, ""))) continue;
348
349 /* eat leading whitespace */
350 line = skip_whitespace(line);
351 /* eat trailing whitespace */
352 i = strlen(line) - 1;
353 while (i >= 0 && isspace(line[i]))
354 line[i--] = '\0';
355
356 for (i = 0; i < ARRAY_SIZE(keywords); i++)
357 if (!strcasecmp(token, keywords[i].keyword))
358 if (!keywords[i].handler(line, keywords[i].var)) {
359 bb_error_msg("cannot parse line %d of %s", lm, file);
360 if (ENABLE_FEATURE_UDHCP_DEBUG)
361 bb_error_msg("cannot parse '%s'", debug_orig);
362 /* reset back to the default value */
363 keywords[i].handler(keywords[i].def, keywords[i].var);
364 }
365 }
366 fclose(in);
367
368 server_config.start_ip = ntohl(server_config.start_ip);
369 server_config.end_ip = ntohl(server_config.end_ip);
370
371 return 1;
372}
373
374
375void write_leases(void)
376{
377 int fp;
378 unsigned i;
379 time_t curr = time(0);
380 unsigned long tmp_time;
381
382 fp = open3_or_warn(server_config.lease_file, O_WRONLY|O_CREAT|O_TRUNC, 0666);
383 if (fp < 0) {
384 return;
385 }
386
387 for (i = 0; i < server_config.max_leases; i++) {
388 if (leases[i].yiaddr != 0) {
389
390 /* screw with the time in the struct, for easier writing */
391 tmp_time = leases[i].expires;
392
393 if (server_config.remaining) {
394 if (lease_expired(&(leases[i])))
395 leases[i].expires = 0;
396 else leases[i].expires -= curr;
397 } /* else stick with the time we got */
398 leases[i].expires = htonl(leases[i].expires);
399 // FIXME: error check??
400 full_write(fp, &leases[i], sizeof(leases[i]));
401
402 /* then restore it when done */
403 leases[i].expires = tmp_time;
404 }
405 }
406 close(fp);
407
408 if (server_config.notify_file) {
409 char *cmd = xasprintf("%s %s", server_config.notify_file, server_config.lease_file);
410 system(cmd);
411 free(cmd);
412 }
413}
414
415
416void read_leases(const char *file)
417{
418 int fp;
419 unsigned int i = 0;
420 struct dhcpOfferedAddr lease;
421
422 fp = open_or_warn(file, O_RDONLY);
423 if (fp < 0) {
424 return;
425 }
426
427 while (i < server_config.max_leases
428 && full_read(fp, &lease, sizeof(lease)) == sizeof(lease)
429 ) {
430 /* ADDME: is it a static lease */
431 uint32_t y = ntohl(lease.yiaddr);
432 if (y >= server_config.start_ip && y <= server_config.end_ip) {
433 lease.expires = ntohl(lease.expires);
434 if (!server_config.remaining)
435 lease.expires -= time(0);
436 if (!(add_lease(lease.chaddr, lease.yiaddr, lease.expires))) {
437 bb_error_msg("too many leases while loading %s", file);
438 break;
439 }
440 i++;
441 }
442 }
443 DEBUG("Read %d leases", i);
444 close(fp);
445}
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