1 /* vi: set sw=4 ts=4: */
3 * files.c -- DHCP server file manipulation *
4 * Rewrite by Russ Dill <Russ.Dill@asu.edu> July 2001
7 #include <netinet/ether.h>
15 * Domain names may have 254 chars, and string options can be 254
16 * chars long. However, 80 bytes will be enough for most, and won't
17 * hog up memory. If you have a special application, change it
19 #define READ_CONFIG_BUF_SIZE 80
21 /* on these functions, make sure you datatype matches */
22 static int read_ip(const char *line, void *arg)
24 struct in_addr *addr = arg;
28 if (!inet_aton(line, addr)) {
29 host = gethostbyname(line);
31 addr->s_addr = *((unsigned long *) host->h_addr_list[0]);
37 static int read_mac(const char *line, void *arg)
39 uint8_t *mac_bytes = arg;
40 struct ether_addr *temp_ether_addr;
43 temp_ether_addr = ether_aton(line);
45 if (temp_ether_addr == NULL)
48 memcpy(mac_bytes, temp_ether_addr, 6);
54 static int read_str(const char *line, void *arg)
65 static int read_u32(const char *line, void *arg)
67 *((uint32_t*)arg) = bb_strtou32(line, NULL, 10);
72 static int read_yn(const char *line, void *arg)
77 if (!strcasecmp("yes", line))
79 else if (!strcasecmp("no", line))
87 /* find option 'code' in opt_list */
88 struct option_set *find_option(struct option_set *opt_list, char code)
90 while (opt_list && opt_list->data[OPT_CODE] < code)
91 opt_list = opt_list->next;
93 if (opt_list && opt_list->data[OPT_CODE] == code) return opt_list;
98 /* add an option to the opt_list */
99 static void attach_option(struct option_set **opt_list,
100 const struct dhcp_option *option, char *buffer, int length)
102 struct option_set *existing, *new, **curr;
104 /* add it to an existing option */
105 existing = find_option(*opt_list, option->code);
107 DEBUG("Attaching option %s to existing member of list", option->name);
108 if (option->flags & OPTION_LIST) {
109 if (existing->data[OPT_LEN] + length <= 255) {
110 existing->data = realloc(existing->data,
111 existing->data[OPT_LEN] + length + 2);
112 memcpy(existing->data + existing->data[OPT_LEN] + 2, buffer, length);
113 existing->data[OPT_LEN] += length;
114 } /* else, ignore the data, we could put this in a second option in the future */
115 } /* else, ignore the new data */
117 DEBUG("Attaching option %s to list", option->name);
119 /* make a new option */
120 new = xmalloc(sizeof(struct option_set));
121 new->data = xmalloc(length + 2);
122 new->data[OPT_CODE] = option->code;
123 new->data[OPT_LEN] = length;
124 memcpy(new->data + 2, buffer, length);
127 while (*curr && (*curr)->data[OPT_CODE] < option->code)
128 curr = &(*curr)->next;
136 /* read a dhcp option and add it to opt_list */
137 static int read_opt(const char *const_line, void *arg)
139 struct option_set **opt_list = arg;
140 char *opt, *val, *endptr;
141 const struct dhcp_option *option;
142 int retval = 0, length;
145 uint16_t *result_u16 = (uint16_t *) buffer;
146 uint32_t *result_u32 = (uint32_t *) buffer;
148 /* Cheat, the only const line we'll actually get is "" */
149 line = (char *) const_line;
150 opt = strtok(line, " \t=");
153 option = dhcp_options;
157 if (!strcasecmp(option->name, opt))
163 val = strtok(NULL, ", \t");
165 length = option_lengths[option->flags & TYPE_MASK];
167 opt = buffer; /* new meaning for variable opt */
168 switch (option->flags & TYPE_MASK) {
170 retval = read_ip(val, buffer);
173 retval = read_ip(val, buffer);
174 if (!(val = strtok(NULL, ", \t/-"))) retval = 0;
175 if (retval) retval = read_ip(val, buffer + 4);
178 length = strlen(val);
180 if (length > 254) length = 254;
186 retval = read_yn(val, buffer);
189 buffer[0] = strtoul(val, &endptr, 0);
190 retval = (endptr[0] == '\0');
193 *result_u16 = htons(strtoul(val, &endptr, 0));
194 retval = (endptr[0] == '\0');
197 *result_u16 = htons(strtol(val, &endptr, 0));
198 retval = (endptr[0] == '\0');
201 *result_u32 = htonl(strtoul(val, &endptr, 0));
202 retval = (endptr[0] == '\0');
205 *result_u32 = htonl(strtol(val, &endptr, 0));
206 retval = (endptr[0] == '\0');
212 attach_option(opt_list, option, opt, length);
213 } while (retval && option->flags & OPTION_LIST);
217 static int read_staticlease(const char *const_line, void *arg)
226 /* Allocate memory for addresses */
227 mac_bytes = xmalloc(sizeof(unsigned char) * 8);
228 ip = xmalloc(sizeof(uint32_t));
231 line = (char *) const_line;
232 mac_string = strtok(line, " \t");
233 read_mac(mac_string, mac_bytes);
236 ip_string = strtok(NULL, " \t");
237 read_ip(ip_string, ip);
239 addStaticLease(arg, mac_bytes, ip);
241 if (ENABLE_FEATURE_UDHCP_DEBUG) printStaticLeases(arg);
247 static const struct config_keyword keywords[] = {
248 /* keyword handler variable address default */
249 {"start", read_ip, &(server_config.start), "192.168.0.20"},
250 {"end", read_ip, &(server_config.end), "192.168.0.254"},
251 {"interface", read_str, &(server_config.interface), "eth0"},
252 {"option", read_opt, &(server_config.options), ""},
253 {"opt", read_opt, &(server_config.options), ""},
254 {"max_leases", read_u32, &(server_config.max_leases), "254"},
255 {"remaining", read_yn, &(server_config.remaining), "yes"},
256 {"auto_time", read_u32, &(server_config.auto_time), "7200"},
257 {"decline_time",read_u32, &(server_config.decline_time),"3600"},
258 {"conflict_time",read_u32,&(server_config.conflict_time),"3600"},
259 {"offer_time", read_u32, &(server_config.offer_time), "60"},
260 {"min_lease", read_u32, &(server_config.min_lease), "60"},
261 {"lease_file", read_str, &(server_config.lease_file), LEASES_FILE},
262 {"pidfile", read_str, &(server_config.pidfile), "/var/run/udhcpd.pid"},
263 {"notify_file", read_str, &(server_config.notify_file), ""},
264 {"siaddr", read_ip, &(server_config.siaddr), "0.0.0.0"},
265 {"sname", read_str, &(server_config.sname), ""},
266 {"boot_file", read_str, &(server_config.boot_file), ""},
267 {"static_lease",read_staticlease, &(server_config.static_leases), ""},
268 /*ADDME: static lease */
273 int read_config(const char *file)
276 char buffer[READ_CONFIG_BUF_SIZE], *token, *line;
279 for (i = 0; keywords[i].keyword[0]; i++)
280 if (keywords[i].def[0])
281 keywords[i].handler(keywords[i].def, keywords[i].var);
283 in = fopen(file, "r");
285 bb_error_msg("cannot open config file: %s", file);
289 while (fgets(buffer, READ_CONFIG_BUF_SIZE, in)) {
290 char debug_orig[READ_CONFIG_BUF_SIZE];
294 p = strchr(buffer, '\n');
296 if (ENABLE_FEATURE_UDHCP_DEBUG) strcpy(debug_orig, buffer);
297 p = strchr(buffer, '#');
300 if (!(token = strtok(buffer, " \t"))) continue;
301 if (!(line = strtok(NULL, ""))) continue;
303 /* eat leading whitespace */
304 line = skip_whitespace(line);
305 /* eat trailing whitespace */
306 i = strlen(line) - 1;
307 while (i >= 0 && isspace(line[i]))
310 for (i = 0; keywords[i].keyword[0]; i++)
311 if (!strcasecmp(token, keywords[i].keyword))
312 if (!keywords[i].handler(line, keywords[i].var)) {
313 bb_error_msg("cannot parse line %d of %s", lm, file);
314 if (ENABLE_FEATURE_UDHCP_DEBUG)
315 bb_error_msg("cannot parse '%s'", debug_orig);
316 /* reset back to the default value */
317 keywords[i].handler(keywords[i].def, keywords[i].var);
325 void write_leases(void)
329 time_t curr = time(0);
330 unsigned long tmp_time;
332 fp = open(server_config.lease_file, O_WRONLY|O_CREAT|O_TRUNC, 0666);
334 bb_error_msg("cannot open %s for writing", server_config.lease_file);
338 for (i = 0; i < server_config.max_leases; i++) {
339 if (leases[i].yiaddr != 0) {
341 /* screw with the time in the struct, for easier writing */
342 tmp_time = leases[i].expires;
344 if (server_config.remaining) {
345 if (lease_expired(&(leases[i])))
346 leases[i].expires = 0;
347 else leases[i].expires -= curr;
348 } /* else stick with the time we got */
349 leases[i].expires = htonl(leases[i].expires);
350 // FIXME: error check??
351 full_write(fp, &leases[i], sizeof(leases[i]));
353 /* then restore it when done */
354 leases[i].expires = tmp_time;
359 if (server_config.notify_file) {
360 char *cmd = xasprintf("%s %s", server_config.notify_file, server_config.lease_file);
367 void read_leases(const char *file)
371 struct dhcpOfferedAddr lease;
373 fp = open(file, O_RDONLY);
375 bb_error_msg("cannot open %s for reading", file);
379 while (i < server_config.max_leases
380 && full_read(fp, &lease, sizeof(lease)) == sizeof(lease)
382 /* ADDME: is it a static lease */
383 if (lease.yiaddr >= server_config.start && lease.yiaddr <= server_config.end) {
384 lease.expires = ntohl(lease.expires);
385 if (!server_config.remaining) lease.expires -= time(0);
386 if (!(add_lease(lease.chaddr, lease.yiaddr, lease.expires))) {
387 bb_error_msg("too many leases while loading %s", file);
393 DEBUG("Read %d leases", i);