1 /* 2 * Copyright 2008, The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 /* Utilities for managing the dhcpcd DHCP client daemon */ 18 19 #include <stdio.h> 20 #include <stdlib.h> 21 #include <string.h> 22 #include <unistd.h> 23 #include <arpa/inet.h> 24 #include <netinet/in.h> 25 26 #include <cutils/properties.h> 27 28 static const char DAEMON_NAME[] = "dhcpcd"; 29 static const char DAEMON_PROP_NAME[] = "init.svc.dhcpcd"; 30 static const char HOSTNAME_PROP_NAME[] = "net.hostname"; 31 static const char DHCP_PROP_NAME_PREFIX[] = "dhcp"; 32 static const int NAP_TIME = 200; /* wait for 200ms at a time */ 33 /* when polling for property values */ 34 static const char DAEMON_NAME_RENEW[] = "iprenew"; 35 static char errmsg[100]; 36 /* interface suffix on dhcpcd */ 37 #define MAX_DAEMON_SUFFIX 25 38 39 /* 40 * Wait for a system property to be assigned a specified value. 41 * If desired_value is NULL, then just wait for the property to 42 * be created with any value. maxwait is the maximum amount of 43 * time in seconds to wait before giving up. 44 */ 45 static int wait_for_property(const char *name, const char *desired_value, int maxwait) 46 { 47 char value[PROPERTY_VALUE_MAX] = {'\0'}; 48 int maxnaps = (maxwait * 1000) / NAP_TIME; 49 50 if (maxnaps < 1) { 51 maxnaps = 1; 52 } 53 54 while (maxnaps-- > 0) { 55 usleep(NAP_TIME * 1000); 56 if (property_get(name, value, NULL)) { 57 if (desired_value == NULL || 58 strcmp(value, desired_value) == 0) { 59 return 0; 60 } 61 } 62 } 63 return -1; /* failure */ 64 } 65 66 static int fill_ip_info(const char *interface, 67 char *ipaddr, 68 char *gateway, 69 uint32_t *prefixLength, 70 char *dns1, 71 char *dns2, 72 char *server, 73 uint32_t *lease) 74 { 75 char prop_name[PROPERTY_KEY_MAX]; 76 char prop_value[PROPERTY_VALUE_MAX]; 77 78 snprintf(prop_name, sizeof(prop_name), "%s.%s.ipaddress", DHCP_PROP_NAME_PREFIX, interface); 79 property_get(prop_name, ipaddr, NULL); 80 81 snprintf(prop_name, sizeof(prop_name), "%s.%s.gateway", DHCP_PROP_NAME_PREFIX, interface); 82 property_get(prop_name, gateway, NULL); 83 84 snprintf(prop_name, sizeof(prop_name), "%s.%s.server", DHCP_PROP_NAME_PREFIX, interface); 85 property_get(prop_name, server, NULL); 86 87 //TODO: Handle IPv6 when we change system property usage 88 if (strcmp(gateway, "0.0.0.0") == 0) { 89 //DHCP server is our best bet as gateway 90 strncpy(gateway, server, PROPERTY_VALUE_MAX); 91 } 92 93 snprintf(prop_name, sizeof(prop_name), "%s.%s.mask", DHCP_PROP_NAME_PREFIX, interface); 94 if (property_get(prop_name, prop_value, NULL)) { 95 int p; 96 // this conversion is v4 only, but this dhcp client is v4 only anyway 97 in_addr_t mask = ntohl(inet_addr(prop_value)); 98 // Check netmask is a valid IP address. ntohl gives NONE response (all 1's) for 99 // non 255.255.255.255 inputs. if we get that value check if it is legit.. 100 if (mask == INADDR_NONE && strcmp(prop_value, "255.255.255.255") != 0) { 101 snprintf(errmsg, sizeof(errmsg), "DHCP gave invalid net mask %s", prop_value); 102 return -1; 103 } 104 for (p = 0; p < 32; p++) { 105 if (mask == 0) break; 106 // check for non-contiguous netmask, e.g., 255.254.255.0 107 if ((mask & 0x80000000) == 0) { 108 snprintf(errmsg, sizeof(errmsg), "DHCP gave invalid net mask %s", prop_value); 109 return -1; 110 } 111 mask = mask << 1; 112 } 113 *prefixLength = p; 114 } 115 snprintf(prop_name, sizeof(prop_name), "%s.%s.dns1", DHCP_PROP_NAME_PREFIX, interface); 116 property_get(prop_name, dns1, NULL); 117 118 snprintf(prop_name, sizeof(prop_name), "%s.%s.dns2", DHCP_PROP_NAME_PREFIX, interface); 119 property_get(prop_name, dns2, NULL); 120 121 snprintf(prop_name, sizeof(prop_name), "%s.%s.leasetime", DHCP_PROP_NAME_PREFIX, interface); 122 if (property_get(prop_name, prop_value, NULL)) { 123 *lease = atol(prop_value); 124 } 125 return 0; 126 } 127 128 static const char *ipaddr_to_string(in_addr_t addr) 129 { 130 struct in_addr in_addr; 131 132 in_addr.s_addr = addr; 133 return inet_ntoa(in_addr); 134 } 135 136 void get_daemon_suffix(const char *interface, char *daemon_suffix) { 137 /* Use p2p suffix for any p2p interface. */ 138 if (strncmp(interface, "p2p",3) == 0) { 139 sprintf(daemon_suffix, "p2p"); 140 } else { 141 snprintf(daemon_suffix, MAX_DAEMON_SUFFIX, "%s", interface); 142 } 143 } 144 145 /* 146 * Start the dhcp client daemon, and wait for it to finish 147 * configuring the interface. 148 */ 149 int dhcp_do_request(const char *interface, 150 char *ipaddr, 151 char *gateway, 152 uint32_t *prefixLength, 153 char *dns1, 154 char *dns2, 155 char *server, 156 uint32_t *lease) 157 { 158 char result_prop_name[PROPERTY_KEY_MAX]; 159 char daemon_prop_name[PROPERTY_KEY_MAX]; 160 char prop_value[PROPERTY_VALUE_MAX] = {'\0'}; 161 char daemon_cmd[PROPERTY_VALUE_MAX * 2]; 162 const char *ctrl_prop = "ctl.start"; 163 const char *desired_status = "running"; 164 char daemon_suffix[MAX_DAEMON_SUFFIX]; 165 166 get_daemon_suffix(interface, daemon_suffix); 167 168 snprintf(result_prop_name, sizeof(result_prop_name), "%s.%s.result", 169 DHCP_PROP_NAME_PREFIX, 170 interface); 171 172 snprintf(daemon_prop_name, sizeof(daemon_prop_name), "%s_%s", 173 DAEMON_PROP_NAME, 174 daemon_suffix); 175 176 /* Erase any previous setting of the dhcp result property */ 177 property_set(result_prop_name, ""); 178 179 /* Start the daemon and wait until it's ready */ 180 if (property_get(HOSTNAME_PROP_NAME, prop_value, NULL) && (prop_value[0] != '\0')) 181 snprintf(daemon_cmd, sizeof(daemon_cmd), "%s_%s:-h %s %s", DAEMON_NAME, daemon_suffix, 182 prop_value, interface); 183 else 184 snprintf(daemon_cmd, sizeof(daemon_cmd), "%s_%s:%s", DAEMON_NAME, daemon_suffix, interface); 185 memset(prop_value, '\0', PROPERTY_VALUE_MAX); 186 property_set(ctrl_prop, daemon_cmd); 187 if (wait_for_property(daemon_prop_name, desired_status, 10) < 0) { 188 snprintf(errmsg, sizeof(errmsg), "%s", "Timed out waiting for dhcpcd to start"); 189 return -1; 190 } 191 192 /* Wait for the daemon to return a result */ 193 if (wait_for_property(result_prop_name, NULL, 30) < 0) { 194 snprintf(errmsg, sizeof(errmsg), "%s", "Timed out waiting for DHCP to finish"); 195 return -1; 196 } 197 198 if (!property_get(result_prop_name, prop_value, NULL)) { 199 /* shouldn't ever happen, given the success of wait_for_property() */ 200 snprintf(errmsg, sizeof(errmsg), "%s", "DHCP result property was not set"); 201 return -1; 202 } 203 if (strcmp(prop_value, "ok") == 0) { 204 char dns_prop_name[PROPERTY_KEY_MAX]; 205 if (fill_ip_info(interface, ipaddr, gateway, prefixLength, dns1, dns2, server, lease) 206 == -1) { 207 return -1; 208 } 209 210 /* copy dns data to system properties - TODO - remove this after we have async 211 * notification of renewal's */ 212 snprintf(dns_prop_name, sizeof(dns_prop_name), "net.%s.dns1", interface); 213 property_set(dns_prop_name, *dns1 ? ipaddr_to_string(*dns1) : ""); 214 snprintf(dns_prop_name, sizeof(dns_prop_name), "net.%s.dns2", interface); 215 property_set(dns_prop_name, *dns2 ? ipaddr_to_string(*dns2) : ""); 216 return 0; 217 } else { 218 snprintf(errmsg, sizeof(errmsg), "DHCP result was %s", prop_value); 219 return -1; 220 } 221 } 222 223 /** 224 * Stop the DHCP client daemon. 225 */ 226 int dhcp_stop(const char *interface) 227 { 228 char result_prop_name[PROPERTY_KEY_MAX]; 229 char daemon_prop_name[PROPERTY_KEY_MAX]; 230 char daemon_cmd[PROPERTY_VALUE_MAX * 2]; 231 const char *ctrl_prop = "ctl.stop"; 232 const char *desired_status = "stopped"; 233 234 char daemon_suffix[MAX_DAEMON_SUFFIX]; 235 236 get_daemon_suffix(interface, daemon_suffix); 237 238 snprintf(result_prop_name, sizeof(result_prop_name), "%s.%s.result", 239 DHCP_PROP_NAME_PREFIX, 240 interface); 241 242 snprintf(daemon_prop_name, sizeof(daemon_prop_name), "%s_%s", 243 DAEMON_PROP_NAME, 244 daemon_suffix); 245 246 snprintf(daemon_cmd, sizeof(daemon_cmd), "%s_%s", DAEMON_NAME, daemon_suffix); 247 248 /* Stop the daemon and wait until it's reported to be stopped */ 249 property_set(ctrl_prop, daemon_cmd); 250 if (wait_for_property(daemon_prop_name, desired_status, 5) < 0) { 251 return -1; 252 } 253 property_set(result_prop_name, "failed"); 254 return 0; 255 } 256 257 /** 258 * Release the current DHCP client lease. 259 */ 260 int dhcp_release_lease(const char *interface) 261 { 262 char daemon_prop_name[PROPERTY_KEY_MAX]; 263 char daemon_cmd[PROPERTY_VALUE_MAX * 2]; 264 const char *ctrl_prop = "ctl.stop"; 265 const char *desired_status = "stopped"; 266 267 char daemon_suffix[MAX_DAEMON_SUFFIX]; 268 269 get_daemon_suffix(interface, daemon_suffix); 270 271 snprintf(daemon_prop_name, sizeof(daemon_prop_name), "%s_%s", 272 DAEMON_PROP_NAME, 273 daemon_suffix); 274 275 snprintf(daemon_cmd, sizeof(daemon_cmd), "%s_%s", DAEMON_NAME, daemon_suffix); 276 277 /* Stop the daemon and wait until it's reported to be stopped */ 278 property_set(ctrl_prop, daemon_cmd); 279 if (wait_for_property(daemon_prop_name, desired_status, 5) < 0) { 280 return -1; 281 } 282 return 0; 283 } 284 285 char *dhcp_get_errmsg() { 286 return errmsg; 287 } 288 289 /** 290 * Run WiMAX dhcp renew service. 291 * "wimax_renew" service shoud be included in init.rc. 292 */ 293 int dhcp_do_request_renew(const char *interface, 294 in_addr_t *ipaddr, 295 in_addr_t *gateway, 296 in_addr_t *mask, 297 in_addr_t *dns1, 298 in_addr_t *dns2, 299 in_addr_t *server, 300 uint32_t *lease) 301 { 302 char result_prop_name[PROPERTY_KEY_MAX]; 303 char prop_value[PROPERTY_VALUE_MAX] = {'\0'}; 304 char daemon_cmd[PROPERTY_VALUE_MAX * 2]; 305 const char *ctrl_prop = "ctl.start"; 306 307 char daemon_suffix[MAX_DAEMON_SUFFIX]; 308 309 get_daemon_suffix(interface, daemon_suffix); 310 311 snprintf(result_prop_name, sizeof(result_prop_name), "%s.%s.result", 312 DHCP_PROP_NAME_PREFIX, 313 interface); 314 315 /* Erase any previous setting of the dhcp result property */ 316 property_set(result_prop_name, ""); 317 318 /* Start the renew daemon and wait until it's ready */ 319 snprintf(daemon_cmd, sizeof(daemon_cmd), "%s_%s:%s", DAEMON_NAME_RENEW, 320 daemon_suffix, interface); 321 memset(prop_value, '\0', PROPERTY_VALUE_MAX); 322 property_set(ctrl_prop, daemon_cmd); 323 324 /* Wait for the daemon to return a result */ 325 if (wait_for_property(result_prop_name, NULL, 30) < 0) { 326 snprintf(errmsg, sizeof(errmsg), "%s", "Timed out waiting for DHCP Renew to finish"); 327 return -1; 328 } 329 330 if (!property_get(result_prop_name, prop_value, NULL)) { 331 /* shouldn't ever happen, given the success of wait_for_property() */ 332 snprintf(errmsg, sizeof(errmsg), "%s", "DHCP Renew result property was not set"); 333 return -1; 334 } 335 if (strcmp(prop_value, "ok") == 0) { 336 fill_ip_info(interface, ipaddr, gateway, mask, dns1, dns2, server, lease); 337 return 0; 338 } else { 339 snprintf(errmsg, sizeof(errmsg), "DHCP Renew result was %s", prop_value); 340 return -1; 341 } 342 } 343
