| /* |
| * Copyright 2008, The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| /* Utilities for managing the dhcpcd DHCP client daemon */ |
| |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <unistd.h> |
| #include <arpa/inet.h> |
| #include <netinet/in.h> |
| |
| #include <cutils/properties.h> |
| |
| static const char DAEMON_NAME[] = "dhcpcd"; |
| static const char DAEMON_PROP_NAME[] = "init.svc.dhcpcd"; |
| static const char HOSTNAME_PROP_NAME[] = "net.hostname"; |
| static const char DHCP_PROP_NAME_PREFIX[] = "dhcp"; |
| static const char DHCP_CONFIG_PATH[] = "/system/etc/dhcpcd/dhcpcd.conf"; |
| static const int NAP_TIME = 200; /* wait for 200ms at a time */ |
| /* when polling for property values */ |
| static const char DAEMON_NAME_RENEW[] = "iprenew"; |
| static char errmsg[100]; |
| /* interface length for dhcpcd daemon start (dhcpcd_<interface> as defined in init.rc file) |
| * or for filling up system properties dhcpcd.<interface>.ipaddress, dhcpcd.<interface>.dns1 |
| * and other properties on a successful bind |
| */ |
| #define MAX_INTERFACE_LENGTH 25 |
| |
| /* |
| * P2p interface names increase sequentially p2p-p2p0-1, p2p-p2p0-2.. after |
| * group formation. This does not work well with system properties which can quickly |
| * exhaust or for specifiying a dhcp start target in init which requires |
| * interface to be pre-defined in init.rc file. |
| * |
| * This function returns a common string p2p for all p2p interfaces. |
| */ |
| void get_p2p_interface_replacement(const char *interface, char *p2p_interface) { |
| /* Use p2p for any interface starting with p2p. */ |
| if (strncmp(interface, "p2p",3) == 0) { |
| strncpy(p2p_interface, "p2p", MAX_INTERFACE_LENGTH); |
| } else { |
| strncpy(p2p_interface, interface, MAX_INTERFACE_LENGTH); |
| } |
| } |
| |
| /* |
| * Wait for a system property to be assigned a specified value. |
| * If desired_value is NULL, then just wait for the property to |
| * be created with any value. maxwait is the maximum amount of |
| * time in seconds to wait before giving up. |
| */ |
| static int wait_for_property(const char *name, const char *desired_value, int maxwait) |
| { |
| char value[PROPERTY_VALUE_MAX] = {'\0'}; |
| int maxnaps = (maxwait * 1000) / NAP_TIME; |
| |
| if (maxnaps < 1) { |
| maxnaps = 1; |
| } |
| |
| while (maxnaps-- >= 0) { |
| if (property_get(name, value, NULL)) { |
| if (desired_value == NULL || |
| strcmp(value, desired_value) == 0) { |
| return 0; |
| } |
| } |
| if (maxnaps >= 0) { |
| usleep(NAP_TIME * 1000); |
| } |
| } |
| return -1; /* failure */ |
| } |
| |
| static int fill_ip_info(const char *interface, |
| char *ipaddr, |
| char *gateway, |
| uint32_t *prefixLength, |
| char *dns[], |
| char *server, |
| uint32_t *lease, |
| char *vendorInfo, |
| char *domain, |
| char *mtu) |
| { |
| char prop_name[PROPERTY_KEY_MAX]; |
| char prop_value[PROPERTY_VALUE_MAX]; |
| /* Interface name after converting p2p0-p2p0-X to p2p to reuse system properties */ |
| char p2p_interface[MAX_INTERFACE_LENGTH]; |
| int x; |
| |
| get_p2p_interface_replacement(interface, p2p_interface); |
| |
| snprintf(prop_name, sizeof(prop_name), "%s.%s.ipaddress", DHCP_PROP_NAME_PREFIX, p2p_interface); |
| property_get(prop_name, ipaddr, NULL); |
| |
| snprintf(prop_name, sizeof(prop_name), "%s.%s.gateway", DHCP_PROP_NAME_PREFIX, p2p_interface); |
| property_get(prop_name, gateway, NULL); |
| |
| snprintf(prop_name, sizeof(prop_name), "%s.%s.server", DHCP_PROP_NAME_PREFIX, p2p_interface); |
| property_get(prop_name, server, NULL); |
| |
| //TODO: Handle IPv6 when we change system property usage |
| if (gateway[0] == '\0' || strncmp(gateway, "0.0.0.0", 7) == 0) { |
| //DHCP server is our best bet as gateway |
| strncpy(gateway, server, PROPERTY_VALUE_MAX); |
| } |
| |
| snprintf(prop_name, sizeof(prop_name), "%s.%s.mask", DHCP_PROP_NAME_PREFIX, p2p_interface); |
| if (property_get(prop_name, prop_value, NULL)) { |
| int p; |
| // this conversion is v4 only, but this dhcp client is v4 only anyway |
| in_addr_t mask = ntohl(inet_addr(prop_value)); |
| // Check netmask is a valid IP address. ntohl gives NONE response (all 1's) for |
| // non 255.255.255.255 inputs. if we get that value check if it is legit.. |
| if (mask == INADDR_NONE && strcmp(prop_value, "255.255.255.255") != 0) { |
| snprintf(errmsg, sizeof(errmsg), "DHCP gave invalid net mask %s", prop_value); |
| return -1; |
| } |
| for (p = 0; p < 32; p++) { |
| if (mask == 0) break; |
| // check for non-contiguous netmask, e.g., 255.254.255.0 |
| if ((mask & 0x80000000) == 0) { |
| snprintf(errmsg, sizeof(errmsg), "DHCP gave invalid net mask %s", prop_value); |
| return -1; |
| } |
| mask = mask << 1; |
| } |
| *prefixLength = p; |
| } |
| |
| for (x=0; dns[x] != NULL; x++) { |
| snprintf(prop_name, sizeof(prop_name), "%s.%s.dns%d", DHCP_PROP_NAME_PREFIX, p2p_interface, x+1); |
| property_get(prop_name, dns[x], NULL); |
| } |
| |
| snprintf(prop_name, sizeof(prop_name), "%s.%s.leasetime", DHCP_PROP_NAME_PREFIX, p2p_interface); |
| if (property_get(prop_name, prop_value, NULL)) { |
| *lease = atol(prop_value); |
| } |
| |
| snprintf(prop_name, sizeof(prop_name), "%s.%s.vendorInfo", DHCP_PROP_NAME_PREFIX, |
| p2p_interface); |
| property_get(prop_name, vendorInfo, NULL); |
| |
| snprintf(prop_name, sizeof(prop_name), "%s.%s.domain", DHCP_PROP_NAME_PREFIX, |
| p2p_interface); |
| property_get(prop_name, domain, NULL); |
| |
| snprintf(prop_name, sizeof(prop_name), "%s.%s.mtu", DHCP_PROP_NAME_PREFIX, |
| p2p_interface); |
| property_get(prop_name, mtu, NULL); |
| |
| return 0; |
| } |
| |
| /* |
| * Start the dhcp client daemon, and wait for it to finish |
| * configuring the interface. |
| * |
| * The device init.rc file needs a corresponding entry for this work. |
| * |
| * Example: |
| * service dhcpcd_<interface> /system/bin/dhcpcd -ABKL -f dhcpcd.conf |
| */ |
| int dhcp_do_request(const char *interface, |
| char *ipaddr, |
| char *gateway, |
| uint32_t *prefixLength, |
| char *dns[], |
| char *server, |
| uint32_t *lease, |
| char *vendorInfo, |
| char *domain, |
| char *mtu) |
| { |
| char result_prop_name[PROPERTY_KEY_MAX]; |
| char daemon_prop_name[PROPERTY_KEY_MAX]; |
| char prop_value[PROPERTY_VALUE_MAX] = {'\0'}; |
| char daemon_cmd[PROPERTY_VALUE_MAX * 2 + sizeof(DHCP_CONFIG_PATH)]; |
| const char *ctrl_prop = "ctl.start"; |
| const char *desired_status = "running"; |
| /* Interface name after converting p2p0-p2p0-X to p2p to reuse system properties */ |
| char p2p_interface[MAX_INTERFACE_LENGTH]; |
| |
| get_p2p_interface_replacement(interface, p2p_interface); |
| |
| snprintf(result_prop_name, sizeof(result_prop_name), "%s.%s.result", |
| DHCP_PROP_NAME_PREFIX, |
| p2p_interface); |
| |
| snprintf(daemon_prop_name, sizeof(daemon_prop_name), "%s_%s", |
| DAEMON_PROP_NAME, |
| p2p_interface); |
| |
| /* Erase any previous setting of the dhcp result property */ |
| property_set(result_prop_name, ""); |
| |
| /* Start the daemon and wait until it's ready */ |
| if (property_get(HOSTNAME_PROP_NAME, prop_value, NULL) && (prop_value[0] != '\0')) |
| snprintf(daemon_cmd, sizeof(daemon_cmd), "%s_%s:-f %s -h %s %s", DAEMON_NAME, |
| p2p_interface, DHCP_CONFIG_PATH, prop_value, interface); |
| else |
| snprintf(daemon_cmd, sizeof(daemon_cmd), "%s_%s:-f %s %s", DAEMON_NAME, |
| p2p_interface, DHCP_CONFIG_PATH, interface); |
| memset(prop_value, '\0', PROPERTY_VALUE_MAX); |
| property_set(ctrl_prop, daemon_cmd); |
| if (wait_for_property(daemon_prop_name, desired_status, 10) < 0) { |
| snprintf(errmsg, sizeof(errmsg), "%s", "Timed out waiting for dhcpcd to start"); |
| return -1; |
| } |
| |
| /* Wait for the daemon to return a result */ |
| if (wait_for_property(result_prop_name, NULL, 30) < 0) { |
| snprintf(errmsg, sizeof(errmsg), "%s", "Timed out waiting for DHCP to finish"); |
| return -1; |
| } |
| |
| if (!property_get(result_prop_name, prop_value, NULL)) { |
| /* shouldn't ever happen, given the success of wait_for_property() */ |
| snprintf(errmsg, sizeof(errmsg), "%s", "DHCP result property was not set"); |
| return -1; |
| } |
| if (strcmp(prop_value, "ok") == 0) { |
| if (fill_ip_info(interface, ipaddr, gateway, prefixLength, dns, |
| server, lease, vendorInfo, domain, mtu) == -1) { |
| return -1; |
| } |
| return 0; |
| } else { |
| snprintf(errmsg, sizeof(errmsg), "DHCP result was %s", prop_value); |
| return -1; |
| } |
| } |
| |
| /** |
| * Stop the DHCP client daemon. |
| */ |
| int dhcp_stop(const char *interface) |
| { |
| char result_prop_name[PROPERTY_KEY_MAX]; |
| char daemon_prop_name[PROPERTY_KEY_MAX]; |
| char daemon_cmd[PROPERTY_VALUE_MAX * 2]; |
| const char *ctrl_prop = "ctl.stop"; |
| const char *desired_status = "stopped"; |
| |
| char p2p_interface[MAX_INTERFACE_LENGTH]; |
| |
| get_p2p_interface_replacement(interface, p2p_interface); |
| |
| snprintf(result_prop_name, sizeof(result_prop_name), "%s.%s.result", |
| DHCP_PROP_NAME_PREFIX, |
| p2p_interface); |
| |
| snprintf(daemon_prop_name, sizeof(daemon_prop_name), "%s_%s", |
| DAEMON_PROP_NAME, |
| p2p_interface); |
| |
| snprintf(daemon_cmd, sizeof(daemon_cmd), "%s_%s", DAEMON_NAME, p2p_interface); |
| |
| /* Stop the daemon and wait until it's reported to be stopped */ |
| property_set(ctrl_prop, daemon_cmd); |
| if (wait_for_property(daemon_prop_name, desired_status, 5) < 0) { |
| return -1; |
| } |
| property_set(result_prop_name, "failed"); |
| return 0; |
| } |
| |
| /** |
| * Release the current DHCP client lease. |
| */ |
| int dhcp_release_lease(const char *interface) |
| { |
| char daemon_prop_name[PROPERTY_KEY_MAX]; |
| char daemon_cmd[PROPERTY_VALUE_MAX * 2]; |
| const char *ctrl_prop = "ctl.stop"; |
| const char *desired_status = "stopped"; |
| |
| char p2p_interface[MAX_INTERFACE_LENGTH]; |
| |
| get_p2p_interface_replacement(interface, p2p_interface); |
| |
| snprintf(daemon_prop_name, sizeof(daemon_prop_name), "%s_%s", |
| DAEMON_PROP_NAME, |
| p2p_interface); |
| |
| snprintf(daemon_cmd, sizeof(daemon_cmd), "%s_%s", DAEMON_NAME, p2p_interface); |
| |
| /* Stop the daemon and wait until it's reported to be stopped */ |
| property_set(ctrl_prop, daemon_cmd); |
| if (wait_for_property(daemon_prop_name, desired_status, 5) < 0) { |
| return -1; |
| } |
| return 0; |
| } |
| |
| char *dhcp_get_errmsg() { |
| return errmsg; |
| } |
| |
| /** |
| * The device init.rc file needs a corresponding entry. |
| * |
| * Example: |
| * service iprenew_<interface> /system/bin/dhcpcd -n |
| * |
| */ |
| int dhcp_do_request_renew(const char *interface, |
| char *ipaddr, |
| char *gateway, |
| uint32_t *prefixLength, |
| char *dns[], |
| char *server, |
| uint32_t *lease, |
| char *vendorInfo, |
| char *domain, |
| char *mtu) |
| { |
| char result_prop_name[PROPERTY_KEY_MAX]; |
| char prop_value[PROPERTY_VALUE_MAX] = {'\0'}; |
| char daemon_cmd[PROPERTY_VALUE_MAX * 2]; |
| const char *ctrl_prop = "ctl.start"; |
| |
| char p2p_interface[MAX_INTERFACE_LENGTH]; |
| |
| get_p2p_interface_replacement(interface, p2p_interface); |
| |
| snprintf(result_prop_name, sizeof(result_prop_name), "%s.%s.result", |
| DHCP_PROP_NAME_PREFIX, |
| p2p_interface); |
| |
| /* Erase any previous setting of the dhcp result property */ |
| property_set(result_prop_name, ""); |
| |
| /* Start the renew daemon and wait until it's ready */ |
| snprintf(daemon_cmd, sizeof(daemon_cmd), "%s_%s:%s", DAEMON_NAME_RENEW, |
| p2p_interface, interface); |
| memset(prop_value, '\0', PROPERTY_VALUE_MAX); |
| property_set(ctrl_prop, daemon_cmd); |
| |
| /* Wait for the daemon to return a result */ |
| if (wait_for_property(result_prop_name, NULL, 30) < 0) { |
| snprintf(errmsg, sizeof(errmsg), "%s", "Timed out waiting for DHCP Renew to finish"); |
| return -1; |
| } |
| |
| if (!property_get(result_prop_name, prop_value, NULL)) { |
| /* shouldn't ever happen, given the success of wait_for_property() */ |
| snprintf(errmsg, sizeof(errmsg), "%s", "DHCP Renew result property was not set"); |
| return -1; |
| } |
| if (strcmp(prop_value, "ok") == 0) { |
| return fill_ip_info(interface, ipaddr, gateway, prefixLength, dns, |
| server, lease, vendorInfo, domain, mtu); |
| } else { |
| snprintf(errmsg, sizeof(errmsg), "DHCP Renew result was %s", prop_value); |
| return -1; |
| } |
| } |
