blob: 7d3de382892913042cd16b3e6d8d947fbf307053 [file] [log] [blame]
/*
* Copyright (C) 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.
*/
#include <stdlib.h>
#include <errno.h>
#include <fcntl.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#define LOG_TAG "SecondaryTablController"
#include <cutils/log.h>
#include <cutils/properties.h>
extern "C" int system_nosh(const char *command);
#include "ResponseCode.h"
#include "NetdConstants.h"
#include "SecondaryTableController.h"
SecondaryTableController::SecondaryTableController() {
int i;
for (i=0; i < INTERFACES_TRACKED; i++) {
mInterfaceTable[i][0] = 0;
// TODO - use a hashtable or other prebuilt container class
mInterfaceRuleCount[i] = 0;
}
}
SecondaryTableController::~SecondaryTableController() {
}
int SecondaryTableController::findTableNumber(const char *iface) {
int i;
for (i = 0; i < INTERFACES_TRACKED; i++) {
// compare through the final null, hence +1
if (strncmp(iface, mInterfaceTable[i], IFNAMSIZ + 1) == 0) {
return i;
}
}
return -1;
}
int SecondaryTableController::addRoute(SocketClient *cli, char *iface, char *dest, int prefix,
char *gateway) {
int tableIndex = findTableNumber(iface);
if (tableIndex == -1) {
tableIndex = findTableNumber(""); // look for an empty slot
if (tableIndex == -1) {
ALOGE("Max number of NATed interfaces reached");
errno = ENODEV;
cli->sendMsg(ResponseCode::OperationFailed, "Max number NATed", true);
return -1;
}
strncpy(mInterfaceTable[tableIndex], iface, IFNAMSIZ);
// Ensure null termination even if truncation happened
mInterfaceTable[tableIndex][IFNAMSIZ] = 0;
}
return modifyRoute(cli, ADD, iface, dest, prefix, gateway, tableIndex);
}
int SecondaryTableController::modifyRoute(SocketClient *cli, const char *action, char *iface,
char *dest, int prefix, char *gateway, int tableIndex) {
char *cmd;
if (strcmp("::", gateway) == 0) {
// IP tool doesn't like "::" - the equiv of 0.0.0.0 that it accepts for ipv4
asprintf(&cmd, "%s route %s %s/%d dev %s table %d",
IP_PATH, action, dest, prefix, iface, tableIndex+BASE_TABLE_NUMBER);
} else {
asprintf(&cmd, "%s route %s %s/%d via %s dev %s table %d",
IP_PATH, action, dest, prefix, gateway, iface, tableIndex+BASE_TABLE_NUMBER);
}
if (runAndFree(cli, cmd)) {
ALOGE("ip route %s failed: %s route %s %s/%d via %s dev %s table %d", action,
IP_PATH, action, dest, prefix, gateway, iface, tableIndex+BASE_TABLE_NUMBER);
errno = ENODEV;
cli->sendMsg(ResponseCode::OperationFailed, "ip route modification failed", true);
return -1;
}
if (strcmp(action, ADD) == 0) {
mInterfaceRuleCount[tableIndex]++;
} else {
if (--mInterfaceRuleCount[tableIndex] < 1) {
mInterfaceRuleCount[tableIndex] = 0;
mInterfaceTable[tableIndex][0] = 0;
}
}
modifyRuleCount(tableIndex, action);
cli->sendMsg(ResponseCode::CommandOkay, "Route modified", false);
return 0;
}
void SecondaryTableController::modifyRuleCount(int tableIndex, const char *action) {
if (strcmp(action, ADD) == 0) {
mInterfaceRuleCount[tableIndex]++;
} else {
if (--mInterfaceRuleCount[tableIndex] < 1) {
mInterfaceRuleCount[tableIndex] = 0;
mInterfaceTable[tableIndex][0] = 0;
}
}
}
int SecondaryTableController::verifyTableIndex(int tableIndex) {
if ((tableIndex < 0) ||
(tableIndex >= INTERFACES_TRACKED) ||
(mInterfaceTable[tableIndex][0] == 0)) {
return -1;
} else {
return 0;
}
}
const char *SecondaryTableController::getVersion(const char *addr) {
if (strchr(addr, ':') != NULL) {
return "-6";
} else {
return "-4";
}
}
int SecondaryTableController::removeRoute(SocketClient *cli, char *iface, char *dest, int prefix,
char *gateway) {
int tableIndex = findTableNumber(iface);
if (tableIndex == -1) {
ALOGE("Interface not found");
errno = ENODEV;
cli->sendMsg(ResponseCode::OperationFailed, "Interface not found", true);
return -1;
}
return modifyRoute(cli, DEL, iface, dest, prefix, gateway, tableIndex);
}
int SecondaryTableController::modifyFromRule(int tableIndex, const char *action,
const char *addr) {
char *cmd;
if (verifyTableIndex(tableIndex)) {
return -1;
}
asprintf(&cmd, "%s %s rule %s from %s table %d", IP_PATH, getVersion(addr),
action, addr, tableIndex + BASE_TABLE_NUMBER);
if (runAndFree(NULL, cmd)) {
return -1;
}
modifyRuleCount(tableIndex, action);
return 0;
}
int SecondaryTableController::modifyLocalRoute(int tableIndex, const char *action,
const char *iface, const char *addr) {
char *cmd;
if (verifyTableIndex(tableIndex)) {
return -1;
}
modifyRuleCount(tableIndex, action); // some del's will fail as the iface is already gone.
asprintf(&cmd, "%s route %s %s dev %s table %d", IP_PATH, action, addr, iface,
tableIndex+BASE_TABLE_NUMBER);
return runAndFree(NULL, cmd);
}
int SecondaryTableController::runAndFree(SocketClient *cli, char *cmd) {
int ret = 0;
if (strlen(cmd) >= 255) {
if (cli != NULL) {
ALOGE("ip command (%s) too long", cmd);
errno = E2BIG;
cli->sendMsg(ResponseCode::CommandSyntaxError, "Too long", true);
}
free(cmd);
return -1;
}
ret = system_nosh(cmd);
free(cmd);
return ret;
}