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 return safe_strtou32(line, (uint32_t*)arg) == 0;
71 static int read_yn(const char *line, void *arg)
76 if (!strcasecmp("yes", line))
78 else if (!strcasecmp("no", line))
86 /* find option 'code' in opt_list */
87 struct option_set *find_option(struct option_set *opt_list, char code)
89 while (opt_list && opt_list->data[OPT_CODE] < code)
90 opt_list = opt_list->next;
92 if (opt_list && opt_list->data[OPT_CODE] == code) return opt_list;
97 /* add an option to the opt_list */
98 static void attach_option(struct option_set **opt_list, struct dhcp_option *option, char *buffer, int length)
100 struct option_set *existing, *new, **curr;
102 /* add it to an existing option */
103 if ((existing = find_option(*opt_list, option->code))) {
104 DEBUG("Attaching option %s to existing member of list", option->name);
105 if (option->flags & OPTION_LIST) {
106 if (existing->data[OPT_LEN] + length <= 255) {
107 existing->data = realloc(existing->data,
108 existing->data[OPT_LEN] + length + 2);
109 memcpy(existing->data + existing->data[OPT_LEN] + 2, buffer, length);
110 existing->data[OPT_LEN] += length;
111 } /* else, ignore the data, we could put this in a second option in the future */
112 } /* else, ignore the new data */
114 DEBUG("Attaching option %s to list", option->name);
116 /* make a new option */
117 new = xmalloc(sizeof(struct option_set));
118 new->data = xmalloc(length + 2);
119 new->data[OPT_CODE] = option->code;
120 new->data[OPT_LEN] = length;
121 memcpy(new->data + 2, buffer, length);
124 while (*curr && (*curr)->data[OPT_CODE] < option->code)
125 curr = &(*curr)->next;
133 /* read a dhcp option and add it to opt_list */
134 static int read_opt(const char *const_line, void *arg)
136 struct option_set **opt_list = arg;
137 char *opt, *val, *endptr;
138 struct dhcp_option *option;
139 int retval = 0, length;
142 uint16_t *result_u16 = (uint16_t *) buffer;
143 uint32_t *result_u32 = (uint32_t *) buffer;
145 /* Cheat, the only const line we'll actually get is "" */
146 line = (char *) const_line;
147 if (!(opt = strtok(line, " \t="))) return 0;
149 for (option = dhcp_options; option->code; option++)
150 if (!strcasecmp(option->name, opt))
153 if (!option->code) return 0;
156 if (!(val = strtok(NULL, ", \t"))) break;
157 length = option_lengths[option->flags & TYPE_MASK];
159 opt = buffer; /* new meaning for variable opt */
160 switch (option->flags & TYPE_MASK) {
162 retval = read_ip(val, buffer);
165 retval = read_ip(val, buffer);
166 if (!(val = strtok(NULL, ", \t/-"))) retval = 0;
167 if (retval) retval = read_ip(val, buffer + 4);
170 length = strlen(val);
172 if (length > 254) length = 254;
178 retval = read_yn(val, buffer);
181 buffer[0] = strtoul(val, &endptr, 0);
182 retval = (endptr[0] == '\0');
185 *result_u16 = htons(strtoul(val, &endptr, 0));
186 retval = (endptr[0] == '\0');
189 *result_u16 = htons(strtol(val, &endptr, 0));
190 retval = (endptr[0] == '\0');
193 *result_u32 = htonl(strtoul(val, &endptr, 0));
194 retval = (endptr[0] == '\0');
197 *result_u32 = htonl(strtol(val, &endptr, 0));
198 retval = (endptr[0] == '\0');
204 attach_option(opt_list, option, opt, length);
205 } while (retval && option->flags & OPTION_LIST);
209 static int read_staticlease(const char *const_line, void *arg)
218 /* Allocate memory for addresses */
219 mac_bytes = xmalloc(sizeof(unsigned char) * 8);
220 ip = xmalloc(sizeof(uint32_t));
223 line = (char *) const_line;
224 mac_string = strtok(line, " \t");
225 read_mac(mac_string, mac_bytes);
228 ip_string = strtok(NULL, " \t");
229 read_ip(ip_string, ip);
231 addStaticLease(arg, mac_bytes, ip);
233 if (ENABLE_FEATURE_UDHCP_DEBUG) printStaticLeases(arg);
239 static const struct config_keyword keywords[] = {
240 /* keyword handler variable address default */
241 {"start", read_ip, &(server_config.start), "192.168.0.20"},
242 {"end", read_ip, &(server_config.end), "192.168.0.254"},
243 {"interface", read_str, &(server_config.interface), "eth0"},
244 {"option", read_opt, &(server_config.options), ""},
245 {"opt", read_opt, &(server_config.options), ""},
246 {"max_leases", read_u32, &(server_config.max_leases), "254"},
247 {"remaining", read_yn, &(server_config.remaining), "yes"},
248 {"auto_time", read_u32, &(server_config.auto_time), "7200"},
249 {"decline_time",read_u32, &(server_config.decline_time),"3600"},
250 {"conflict_time",read_u32,&(server_config.conflict_time),"3600"},
251 {"offer_time", read_u32, &(server_config.offer_time), "60"},
252 {"min_lease", read_u32, &(server_config.min_lease), "60"},
253 {"lease_file", read_str, &(server_config.lease_file), LEASES_FILE},
254 {"pidfile", read_str, &(server_config.pidfile), "/var/run/udhcpd.pid"},
255 {"notify_file", read_str, &(server_config.notify_file), ""},
256 {"siaddr", read_ip, &(server_config.siaddr), "0.0.0.0"},
257 {"sname", read_str, &(server_config.sname), ""},
258 {"boot_file", read_str, &(server_config.boot_file), ""},
259 {"static_lease",read_staticlease, &(server_config.static_leases), ""},
260 /*ADDME: static lease */
265 int read_config(const char *file)
268 char buffer[READ_CONFIG_BUF_SIZE], *token, *line;
271 for (i = 0; keywords[i].keyword[0]; i++)
272 if (keywords[i].def[0])
273 keywords[i].handler(keywords[i].def, keywords[i].var);
275 if (!(in = fopen(file, "r"))) {
276 bb_error_msg("unable to open config file: %s", file);
280 while (fgets(buffer, READ_CONFIG_BUF_SIZE, in)) {
281 char debug_orig[READ_CONFIG_BUF_SIZE];
284 if (strchr(buffer, '\n')) *(strchr(buffer, '\n')) = '\0';
285 if (ENABLE_FEATURE_UDHCP_DEBUG) strcpy(debug_orig, buffer);
286 if (strchr(buffer, '#')) *(strchr(buffer, '#')) = '\0';
288 if (!(token = strtok(buffer, " \t"))) continue;
289 if (!(line = strtok(NULL, ""))) continue;
291 /* eat leading whitespace */
292 line = line + strspn(line, " \t=");
293 /* eat trailing whitespace */
294 for (i = strlen(line); i > 0 && isspace(line[i - 1]); i--);
297 for (i = 0; keywords[i].keyword[0]; i++)
298 if (!strcasecmp(token, keywords[i].keyword))
299 if (!keywords[i].handler(line, keywords[i].var)) {
300 bb_error_msg("cannot parse line %d of %s", lm, file);
301 if (ENABLE_FEATURE_UDHCP_DEBUG)
302 bb_error_msg("cannot parse '%s'", debug_orig);
303 /* reset back to the default value */
304 keywords[i].handler(keywords[i].def, keywords[i].var);
312 void write_leases(void)
317 time_t curr = time(0);
318 unsigned long tmp_time;
320 if (!(fp = fopen(server_config.lease_file, "w"))) {
321 bb_error_msg("unable to open %s for writing", server_config.lease_file);
325 for (i = 0; i < server_config.max_leases; i++) {
326 if (leases[i].yiaddr != 0) {
328 /* screw with the time in the struct, for easier writing */
329 tmp_time = leases[i].expires;
331 if (server_config.remaining) {
332 if (lease_expired(&(leases[i])))
333 leases[i].expires = 0;
334 else leases[i].expires -= curr;
335 } /* else stick with the time we got */
336 leases[i].expires = htonl(leases[i].expires);
337 fwrite(&leases[i], sizeof(struct dhcpOfferedAddr), 1, fp);
339 /* Then restore it when done. */
340 leases[i].expires = tmp_time;
345 if (server_config.notify_file) {
346 sprintf(buf, "%s %s", server_config.notify_file, server_config.lease_file);
352 void read_leases(const char *file)
356 struct dhcpOfferedAddr lease;
358 if (!(fp = fopen(file, "r"))) {
359 bb_error_msg("unable to open %s for reading", file);
363 while (i < server_config.max_leases && (fread(&lease, sizeof lease, 1, fp) == 1)) {
364 /* ADDME: is it a static lease */
365 if (lease.yiaddr >= server_config.start && lease.yiaddr <= server_config.end) {
366 lease.expires = ntohl(lease.expires);
367 if (!server_config.remaining) lease.expires -= time(0);
368 if (!(add_lease(lease.chaddr, lease.yiaddr, lease.expires))) {
369 bb_error_msg("too many leases while loading %s", file);
375 DEBUG("Read %d leases", i);