1/* 2 * files.c -- DHCP server file manipulation * 3 * Rewrite by Russ Dill <Russ.Dill@asu.edu> July 2001 4 */ 5#include <stdio.h> 6#include <stdlib.h> 7#include <string.h> 8 9#include <sys/socket.h> 10#include <arpa/inet.h> 11#include <time.h> 12#include <ctype.h> 13#include <netdb.h> 14 15#include "debug.h" 16#include "dhcpd.h" 17#include "files.h" 18#include "options.h" 19#include "leases.h" 20 21/* on these functions, make sure you datatype matches */ 22/* foxconn modified start, wenchia, 06/25/2007 */ 23/* fix alignment issue in DG834GUv5 */ 24/* original code*/ 25/* 26static int read_ip(char *line, void *arg) 27{ 28 struct in_addr *addr = arg; 29 struct hostent *host; 30 int retval = 1; 31 32 if (!inet_aton(line, addr)) { 33 if ((host = gethostbyname(line))) 34 addr->s_addr = *((unsigned long *) host->h_addr_list[0]); 35 else retval = 0; 36 } 37 return retval; 38} 39*/ 40 41static int read_ip(char *line, void *arg) 42{ 43 struct in_addr addr; 44 struct hostent *host; 45 int retval = 1; 46 47 if (!inet_aton(line, &addr)) { 48 if ((host = gethostbyname(line))) 49 addr.s_addr = *((unsigned long *) host->h_addr_list[0]); 50 else retval = 0; 51 } 52 memcpy((char*)arg, (char*)&addr, sizeof(struct in_addr)); 53 return retval; 54} 55/* foxconn modified end, wenchia, 06/25/2007 */ 56 57 58static int read_str(char *line, void *arg) 59{ 60 char **dest = arg; 61 62 if (*dest) free(*dest); 63 *dest = strdup(line); 64 65 return 1; 66} 67 68 69static int read_u32(char *line, void *arg) 70{ 71 u_int32_t *dest = arg; 72 char *endptr; 73 *dest = strtoul(line, &endptr, 0); 74 return endptr[0] == '\0'; 75} 76 77 78static int read_yn(char *line, void *arg) 79{ 80 char *dest = arg; 81 int retval = 1; 82 83 if (!strcasecmp("yes", line)) 84 *dest = 1; 85 else if (!strcasecmp("no", line)) 86 *dest = 0; 87 else retval = 0; 88 89 return retval; 90} 91 92 93/* read a dhcp option and add it to opt_list */ 94static int read_opt(char *line, void *arg) 95{ 96 struct option_set **opt_list = arg; 97 char *opt, *val, *endptr; 98 struct dhcp_option *option = NULL; 99 int retval = 0, length = 0; 100 char buffer[255]; 101 u_int16_t result_u16; 102 u_int32_t result_u32; 103 int i; 104 105 if (!(opt = strtok(line, " \t="))) return 0; 106 107 for (i = 0; options[i].code; i++) 108 if (!strcmp(options[i].name, opt)) 109 option = &(options[i]); 110 111 if (!option) return 0; 112 113 do { 114 val = strtok(NULL, ", \t"); 115 if (val) { 116 length = option_lengths[option->flags & TYPE_MASK]; 117 retval = 0; 118 switch (option->flags & TYPE_MASK) { 119 case OPTION_IP: 120 retval = read_ip(val, buffer); 121 break; 122 case OPTION_IP_PAIR: 123 retval = read_ip(val, buffer); 124 if (!(val = strtok(NULL, ", \t/-"))) retval = 0; 125 if (retval) retval = read_ip(val, buffer + 4); 126 break; 127 case OPTION_STRING: 128 length = strlen(val); 129 if (length > 0) { 130 if (length > 254) length = 254; 131 memcpy(buffer, val, length); 132 retval = 1; 133 } 134 break; 135 case OPTION_BOOLEAN: 136 retval = read_yn(val, buffer); 137 break; 138 case OPTION_U8: 139 buffer[0] = strtoul(val, &endptr, 0); 140 retval = (endptr[0] == '\0'); 141 break; 142 case OPTION_U16: 143 result_u16 = htons(strtoul(val, &endptr, 0)); 144 memcpy(buffer, &result_u16, 2); 145 retval = (endptr[0] == '\0'); 146 break; 147 case OPTION_S16: 148 result_u16 = htons(strtol(val, &endptr, 0)); 149 memcpy(buffer, &result_u16, 2); 150 retval = (endptr[0] == '\0'); 151 break; 152 case OPTION_U32: 153 result_u32 = htonl(strtoul(val, &endptr, 0)); 154 memcpy(buffer, &result_u32, 4); 155 retval = (endptr[0] == '\0'); 156 break; 157 case OPTION_S32: 158 result_u32 = htonl(strtol(val, &endptr, 0)); 159 memcpy(buffer, &result_u32, 4); 160 retval = (endptr[0] == '\0'); 161 break; 162 default: 163 break; 164 } 165 if (retval) 166 attach_option(opt_list, option, buffer, length); 167 }; 168 } while (val && retval && option->flags & OPTION_LIST); 169 return retval; 170} 171 172 173static struct config_keyword keywords[] = { 174 /* keyword[14] handler variable address default[20] */ 175 {"start", read_ip, &(server_config.start), "192.168.0.20"}, 176 {"end", read_ip, &(server_config.end), "192.168.0.254"}, 177 {"interface", read_str, &(server_config.interface), "eth0"}, 178 {"option", read_opt, &(server_config.options), ""}, 179 {"opt", read_opt, &(server_config.options), ""}, 180 {"max_leases", read_u32, &(server_config.max_leases), "254"}, 181 {"remaining", read_yn, &(server_config.remaining), "yes"}, 182 {"auto_time", read_u32, &(server_config.auto_time), "7200"}, 183 {"decline_time",read_u32, &(server_config.decline_time),"3600"}, 184 {"conflict_time",read_u32,&(server_config.conflict_time),"3600"}, 185 {"offer_time", read_u32, &(server_config.offer_time), "60"}, 186 {"min_lease", read_u32, &(server_config.min_lease), "60"}, 187 {"lease_file", read_str, &(server_config.lease_file), "/var/lib/misc/udhcpd.leases"}, 188 {"pidfile", read_str, &(server_config.pidfile), "/var/run/udhcpd.pid"}, 189 {"notify_file", read_str, &(server_config.notify_file), ""}, 190 {"siaddr", read_ip, &(server_config.siaddr), "0.0.0.0"}, 191 {"sname", read_str, &(server_config.sname), ""}, 192 {"boot_file", read_str, &(server_config.boot_file), ""}, 193 /*ADDME: static lease */ 194 {"", NULL, NULL, ""} 195}; 196 197 198int read_config(char *file) 199{ 200 FILE *in; 201 char buffer[80], orig[80], *token, *line; 202 int i; 203 204 for (i = 0; strlen(keywords[i].keyword); i++) 205 if (strlen(keywords[i].def)) 206 keywords[i].handler(keywords[i].def, keywords[i].var); 207 208 if (!(in = fopen(file, "r"))) { 209 LOG(LOG_ERR, "unable to open config file: %s", file); 210 return 0; 211 } 212 213 while (fgets(buffer, 80, in)) { 214 if (strchr(buffer, '\n')) *(strchr(buffer, '\n')) = '\0'; 215 strncpy(orig, buffer, 80); 216 if (strchr(buffer, '#')) *(strchr(buffer, '#')) = '\0'; 217 token = buffer + strspn(buffer, " \t"); 218 if (*token == '\0') continue; 219 line = token + strcspn(token, " \t="); 220 if (*line == '\0') continue; 221 *line = '\0'; 222 line++; 223 224 /* eat leading whitespace */ 225 line = line + strspn(line, " \t="); 226 /* eat trailing whitespace */ 227 for (i = strlen(line); i > 0 && isspace(line[i - 1]); i--); 228 line[i] = '\0'; 229 230 for (i = 0; strlen(keywords[i].keyword); i++) 231 if (!strcasecmp(token, keywords[i].keyword)) 232 if (!keywords[i].handler(line, keywords[i].var)) { 233 LOG(LOG_ERR, "unable to parse '%s'", orig); 234 /* reset back to the default value */ 235 keywords[i].handler(keywords[i].def, keywords[i].var); 236 } 237 } 238 fclose(in); 239 return 1; 240} 241 242 243void write_leases(void) 244{ 245 FILE *fp; 246 unsigned int i; 247 char buf[255]; 248 time_t curr = time(0); 249 unsigned long lease_time; 250 251 if (!(fp = fopen(server_config.lease_file, "w"))) { 252 LOG(LOG_ERR, "Unable to open %s for writing", server_config.lease_file); 253 return; 254 } 255 256 for (i = 0; i < server_config.max_leases; i++) { 257 if (leases[i].yiaddr != 0) { 258 if (server_config.remaining) { 259 if (lease_expired(&(leases[i]))) 260 lease_time = 0; 261 else lease_time = leases[i].expires - curr; 262 } else lease_time = leases[i].expires; 263 lease_time = htonl(lease_time); 264 fwrite(leases[i].chaddr, 16, 1, fp); 265 fwrite(&(leases[i].yiaddr), 4, 1, fp); 266 fwrite(&lease_time, 4, 1, fp); 267 fwrite(leases[i].hostname, 64, 1, fp); 268 } 269 } 270 fclose(fp); 271 272 if (server_config.notify_file) { 273 sprintf(buf, "%s %s", server_config.notify_file, server_config.lease_file); 274 system(buf); 275 } 276} 277 278 279void read_leases(char *file) 280{ 281 FILE *fp; 282 unsigned int i = 0; 283 struct dhcpOfferedAddr lease, *oldest; 284 285 if (!(fp = fopen(file, "r"))) { 286 LOG(LOG_ERR, "Unable to open %s for reading", file); 287 return; 288 } 289 290 while (i < server_config.max_leases && (fread(&lease, sizeof lease, 1, fp) == 1)) { 291 /* ADDME: is it a static lease */ 292 if (lease.yiaddr >= server_config.start && lease.yiaddr <= server_config.end) { 293 lease.expires = ntohl(lease.expires); 294 if (!server_config.remaining) lease.expires -= time(0); 295 if (!(oldest = add_lease(lease.chaddr, lease.yiaddr, lease.expires))) { 296 LOG(LOG_WARNING, "Too many leases while loading %s\n", file); 297 break; 298 } 299 strncpy(oldest->hostname, lease.hostname, sizeof(oldest->hostname) - 1); 300 oldest->hostname[sizeof(oldest->hostname) - 1] = '\0'; 301 i++; 302 } 303 } 304 DEBUG(LOG_INFO, "Read %d leases", i); 305 fclose(fp); 306} 307 308 309