2 * files.c -- DHCP server file manipulation *
3 * Rewrite by Russ Dill <Russ.Dill@asu.edu> July 2001
6 #include <sys/socket.h>
20 * Domain names may have 254 chars, and string options can be 254
21 * chars long. However, 80 bytes will be enough for most, and won't
22 * hog up memory. If you have a special application, change it
24 #define READ_CONFIG_BUF_SIZE 80
26 /* on these functions, make sure you datatype matches */
27 static int read_ip(const char *line, void *arg)
29 struct in_addr *addr = arg;
33 if (!inet_aton(line, addr)) {
34 if ((host = gethostbyname(line)))
35 addr->s_addr = *((unsigned long *) host->h_addr_list[0]);
42 static int read_str(const char *line, void *arg)
46 if (*dest) free(*dest);
53 static int read_u32(const char *line, void *arg)
57 *dest = strtoul(line, &endptr, 0);
58 return endptr[0] == '\0';
62 static int read_yn(const char *line, void *arg)
67 if (!strcasecmp("yes", line))
69 else if (!strcasecmp("no", line))
77 /* read a dhcp option and add it to opt_list */
78 static int read_opt(const char *const_line, void *arg)
80 struct option_set **opt_list = arg;
81 char *opt, *val, *endptr;
82 struct dhcp_option *option;
83 int retval = 0, length;
86 uint16_t *result_u16 = (uint16_t *) buffer;
87 uint32_t *result_u32 = (uint32_t *) buffer;
89 /* Cheat, the only const line we'll actually get is "" */
90 line = (char *) const_line;
91 if (!(opt = strtok(line, " \t="))) return 0;
93 for (option = dhcp_options; option->code; option++)
94 if (!strcasecmp(option->name, opt))
97 if (!option->code) return 0;
100 if (!(val = strtok(NULL, ", \t"))) break;
101 length = option_lengths[option->flags & TYPE_MASK];
103 opt = buffer; /* new meaning for variable opt */
104 switch (option->flags & TYPE_MASK) {
106 retval = read_ip(val, buffer);
109 retval = read_ip(val, buffer);
110 if (!(val = strtok(NULL, ", \t/-"))) retval = 0;
111 if (retval) retval = read_ip(val, buffer + 4);
114 length = strlen(val);
116 if (length > 254) length = 254;
122 retval = read_yn(val, buffer);
125 buffer[0] = strtoul(val, &endptr, 0);
126 retval = (endptr[0] == '\0');
129 *result_u16 = htons(strtoul(val, &endptr, 0));
130 retval = (endptr[0] == '\0');
133 *result_u16 = htons(strtol(val, &endptr, 0));
134 retval = (endptr[0] == '\0');
137 *result_u32 = htonl(strtoul(val, &endptr, 0));
138 retval = (endptr[0] == '\0');
141 *result_u32 = htonl(strtol(val, &endptr, 0));
142 retval = (endptr[0] == '\0');
148 attach_option(opt_list, option, opt, length);
149 } while (retval && option->flags & OPTION_LIST);
154 static const struct config_keyword keywords[] = {
155 /* keyword handler variable address default */
156 {"start", read_ip, &(server_config.start), "192.168.0.20"},
157 {"end", read_ip, &(server_config.end), "192.168.0.254"},
158 {"interface", read_str, &(server_config.interface), "eth0"},
159 {"option", read_opt, &(server_config.options), ""},
160 {"opt", read_opt, &(server_config.options), ""},
161 {"max_leases", read_u32, &(server_config.max_leases), "254"},
162 {"remaining", read_yn, &(server_config.remaining), "yes"},
163 {"auto_time", read_u32, &(server_config.auto_time), "7200"},
164 {"decline_time",read_u32, &(server_config.decline_time),"3600"},
165 {"conflict_time",read_u32,&(server_config.conflict_time),"3600"},
166 {"offer_time", read_u32, &(server_config.offer_time), "60"},
167 {"min_lease", read_u32, &(server_config.min_lease), "60"},
168 {"lease_file", read_str, &(server_config.lease_file), LEASES_FILE},
169 {"pidfile", read_str, &(server_config.pidfile), "/var/run/udhcpd.pid"},
170 {"notify_file", read_str, &(server_config.notify_file), ""},
171 {"siaddr", read_ip, &(server_config.siaddr), "0.0.0.0"},
172 {"sname", read_str, &(server_config.sname), ""},
173 {"boot_file", read_str, &(server_config.boot_file), ""},
174 /*ADDME: static lease */
179 int read_config(const char *file)
182 char buffer[READ_CONFIG_BUF_SIZE], *token, *line;
184 char orig[READ_CONFIG_BUF_SIZE];
188 for (i = 0; keywords[i].keyword[0]; i++)
189 if (keywords[i].def[0])
190 keywords[i].handler(keywords[i].def, keywords[i].var);
192 if (!(in = fopen(file, "r"))) {
193 LOG(LOG_ERR, "unable to open config file: %s", file);
197 while (fgets(buffer, READ_CONFIG_BUF_SIZE, in)) {
199 if (strchr(buffer, '\n')) *(strchr(buffer, '\n')) = '\0';
201 strcpy(orig, buffer);
203 if (strchr(buffer, '#')) *(strchr(buffer, '#')) = '\0';
205 if (!(token = strtok(buffer, " \t"))) continue;
206 if (!(line = strtok(NULL, ""))) continue;
208 /* eat leading whitespace */
209 line = line + strspn(line, " \t=");
210 /* eat trailing whitespace */
211 for (i = strlen(line); i > 0 && isspace(line[i - 1]); i--);
214 for (i = 0; keywords[i].keyword[0]; i++)
215 if (!strcasecmp(token, keywords[i].keyword))
216 if (!keywords[i].handler(line, keywords[i].var)) {
217 LOG(LOG_ERR, "Failure parsing line %d of %s", lm, file);
218 DEBUG(LOG_ERR, "unable to parse '%s'", orig);
219 /* reset back to the default value */
220 keywords[i].handler(keywords[i].def, keywords[i].var);
228 void write_leases(void)
233 time_t curr = time(0);
234 unsigned long tmp_time;
236 if (!(fp = fopen(server_config.lease_file, "w"))) {
237 LOG(LOG_ERR, "Unable to open %s for writing", server_config.lease_file);
241 for (i = 0; i < server_config.max_leases; i++) {
242 if (leases[i].yiaddr != 0) {
244 /* screw with the time in the struct, for easier writing */
245 tmp_time = leases[i].expires;
247 if (server_config.remaining) {
248 if (lease_expired(&(leases[i])))
249 leases[i].expires = 0;
250 else leases[i].expires -= curr;
251 } /* else stick with the time we got */
252 leases[i].expires = htonl(leases[i].expires);
253 fwrite(&leases[i], sizeof(struct dhcpOfferedAddr), 1, fp);
255 /* Then restore it when done. */
256 leases[i].expires = tmp_time;
261 if (server_config.notify_file) {
262 sprintf(buf, "%s %s", server_config.notify_file, server_config.lease_file);
268 void read_leases(const char *file)
272 struct dhcpOfferedAddr lease;
274 if (!(fp = fopen(file, "r"))) {
275 LOG(LOG_ERR, "Unable to open %s for reading", file);
279 while (i < server_config.max_leases && (fread(&lease, sizeof lease, 1, fp) == 1)) {
280 /* ADDME: is it a static lease */
281 if (lease.yiaddr >= server_config.start && lease.yiaddr <= server_config.end) {
282 lease.expires = ntohl(lease.expires);
283 if (!server_config.remaining) lease.expires -= time(0);
284 if (!(add_lease(lease.chaddr, lease.yiaddr, lease.expires))) {
285 LOG(LOG_WARNING, "Too many leases while loading %s\n", file);
291 DEBUG(LOG_INFO, "Read %d leases", i);