diff options
Diffstat (limited to 'app/src/main/java/se/leap/bitmaskclient/firewall/SetupTetheringTask.java')
-rw-r--r-- | app/src/main/java/se/leap/bitmaskclient/firewall/SetupTetheringTask.java | 220 |
1 files changed, 220 insertions, 0 deletions
diff --git a/app/src/main/java/se/leap/bitmaskclient/firewall/SetupTetheringTask.java b/app/src/main/java/se/leap/bitmaskclient/firewall/SetupTetheringTask.java new file mode 100644 index 00000000..7abd01a8 --- /dev/null +++ b/app/src/main/java/se/leap/bitmaskclient/firewall/SetupTetheringTask.java @@ -0,0 +1,220 @@ +/** + * Copyright (c) 2020 LEAP Encryption Access Project and contributers + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ +package se.leap.bitmaskclient.firewall; + +import android.os.AsyncTask; +import android.util.Log; + +import java.lang.ref.WeakReference; +import java.net.NetworkInterface; +import java.util.ArrayList; +import java.util.Enumeration; + +import se.leap.bitmaskclient.tethering.TetheringObservable; +import se.leap.bitmaskclient.tethering.TetheringState; + +import static se.leap.bitmaskclient.firewall.FirewallManager.BITMASK_FORWARD; +import static se.leap.bitmaskclient.firewall.FirewallManager.BITMASK_POSTROUTING; +import static se.leap.bitmaskclient.utils.Cmd.runBlockingCmd; + +public class SetupTetheringTask extends AsyncTask<Void, Boolean, Boolean> { + + private static final String TAG = SetupTetheringTask.class.getSimpleName(); + private WeakReference<FirewallCallback> callbackWeakReference; + + SetupTetheringTask(FirewallCallback callback) { + callbackWeakReference = new WeakReference<>(callback); + } + + @Override + protected Boolean doInBackground(Void... args) { + TetheringState tetheringState = TetheringObservable.getInstance().getTetheringState(); + StringBuilder log = new StringBuilder(); + + String[] bitmaskChain = new String[]{ + "su", + "id", + "iptables -t filter --list " + BITMASK_FORWARD + " && iptables -t nat --list " + BITMASK_POSTROUTING }; + + try { + boolean hasBitmaskChain = runBlockingCmd(bitmaskChain, log) == 0; + boolean allowSu = log.toString().contains("uid=0"); + FirewallCallback callback = callbackWeakReference.get(); + if (callback != null) { + callback.onSuRequested(allowSu); + } + if (!allowSu) { + return false; + } + + boolean success = true; + log = new StringBuilder(); + + if (!hasBitmaskChain && tetheringState.hasAnyVpnTetheringAllowed() && tetheringState.hasAnyDeviceTetheringEnabled()) { + createChains(log); + } + + if (tetheringState.tetherWifiVpn()) { + log = new StringBuilder(); + success = addWifiTetheringRules(tetheringState, log); + logError(success, log); + } else if (!tetheringState.isVpnWifiTetheringAllowed){ + success = removeWifiTetheringRules(tetheringState, log); + logError(success, log); + } + + log = new StringBuilder(); + if (tetheringState.tetherUsbVpn()) { + success = success && addUsbTetheringRules(tetheringState, log); + logError(success, log); + } else if (!tetheringState.isVpnUsbTetheringAllowed) { + success = success && removeUsbTetheringRules(tetheringState, log); + logError(success, log); + } + + log = new StringBuilder(); + if (tetheringState.tetherBluetoothVpn()) { + success = success && addBluetoothTetheringRules(tetheringState, log); + logError(success, log); + } else if (!tetheringState.isVpnBluetoothTetheringAllowed) { + success = success && removeBluetoothTetheringRules(tetheringState, log); + logError(success, log); + } + return success; + } catch (Exception e) { + e.printStackTrace(); + Log.e(FirewallManager.TAG, log.toString()); + } + return false; + } + + private void logError(boolean success, StringBuilder log) { + if (!success) { + Log.e(TAG, log.toString()); + } + } + + + private void createChains(StringBuilder log) throws Exception { + boolean success; + String[] createChains = new String[]{ + "su", + "iptables -t filter --new-chain " + BITMASK_FORWARD, + "iptables -t nat --new-chain " + BITMASK_POSTROUTING, + "iptables -t filter --insert FORWARD --jump " + BITMASK_FORWARD, + "iptables -t nat --insert POSTROUTING --jump " + BITMASK_POSTROUTING, + }; + success = runBlockingCmd(createChains, log) == 0; + Log.d(FirewallManager.TAG, "added " + BITMASK_FORWARD + " and " + BITMASK_POSTROUTING+" to iptables: " + success); + Log.d(FirewallManager.TAG, log.toString()); + } + + private boolean addWifiTetheringRules(TetheringState state, StringBuilder log) throws Exception { + Log.d(TAG, "add Wifi tethering Rules"); + String[] addRules = getAdditionRules(state.wifiAddress, state.wifiInterface); + return runBlockingCmd(addRules, log) == 0; + } + + private boolean removeWifiTetheringRules(TetheringState state, StringBuilder log) throws Exception { + Log.d(TAG, "add Wifi tethering Rules"); + String[] removeRules = getDeletionRules(state, state.lastSeenWifiAddress, state.lastSeenWifiInterface); + return runBlockingCmd(removeRules, log) == 0; + } + + private boolean addUsbTetheringRules(TetheringState state, StringBuilder log) throws Exception { + Log.d(TAG, "add usb tethering rules"); + String[] addRules = getAdditionRules(state.usbAddress, state.usbInterface); + return runBlockingCmd(addRules, log) == 0; + } + + private boolean removeUsbTetheringRules(TetheringState state, StringBuilder log) throws Exception { + Log.d(TAG, "add usb tethering rules"); + String[] addRules = getDeletionRules(state, state.lastSeenUsbAddress, state.lastSeenUsbInterface); + return runBlockingCmd(addRules, log) == 0; + } + + //TODO: implement the follwing methods -v + private boolean removeBluetoothTetheringRules(TetheringState state, StringBuilder log) { + return true; + } + + private boolean addBluetoothTetheringRules(TetheringState state, StringBuilder log) { + return true; + } + + private String[] getAdditionRules(String addressRange, String interfaceName) { + return new String[] { + "su", + "iptables -t filter --flush " + BITMASK_FORWARD, + "iptables -t nat --flush " + BITMASK_POSTROUTING, + "iptables -t filter --append " + BITMASK_FORWARD + " --jump ACCEPT", + "iptables -t nat --append " + BITMASK_POSTROUTING + " --jump MASQUERADE", + "if [[ ! `ip rule show from "+ addressRange+" lookup 61` ]]; " + + "then ip rule add from " + addressRange + " lookup 61; " + + "fi", + "if [[ ! `ip route list table 61 | grep 'default dev " + getTunName() + " scope link'` ]]; " + + "then ip route add default dev " + getTunName() + " scope link table 61; " + + "fi", + "if [[ ! `ip route list table 61 | grep '"+ addressRange +" dev "+ interfaceName +" scope link'` ]]; " + + "then ip route add " + addressRange + " dev " + interfaceName + " scope link table 61; " + + "fi", + "if [[ ! `ip route list table 61 | grep 'broadcast 255.255.255.255 dev " + interfaceName + " scope link'` ]]; " + + "then ip route add broadcast 255.255.255.255 dev " + interfaceName + " scope link table 61; " + + "fi" + }; + } + + private String[] getDeletionRules(TetheringState state, String addressRange, String interfaceName) { + ArrayList<String> list = new ArrayList<>(); + list.add("su"); + list.add("ip route delete broadcast 255.255.255.255 dev " + addressRange +" scope link table 61"); + list.add("ip route delete " + addressRange + " dev " + interfaceName +" scope link table 61"); + if (!state.hasAnyVpnTetheringAllowed() || !state.hasAnyDeviceTetheringEnabled()) { + list.add("ip route delete default dev " + getTunName() + " scope link table 61"); + } + list.add("if [[ `ip rule show from " + addressRange + " lookup 61` ]]; " + + "then ip rule del from " + addressRange + " lookup 61; " + + "fi"); + + return list.toArray(new String[0]); + } + + + + private String getTunName() { + try { + for (Enumeration<NetworkInterface> en = NetworkInterface.getNetworkInterfaces(); en.hasMoreElements(); ) { + NetworkInterface networkInterface = en.nextElement(); + if (networkInterface.getName().contains("tun")) { + return networkInterface.getName(); + } + } + } catch (Exception e) { + e.printStackTrace(); + } + return ""; + } + + @Override + protected void onPostExecute(Boolean result) { + super.onPostExecute(result); + FirewallCallback callback = callbackWeakReference.get(); + if (callback != null) { + callback.onTetheringStarted(result); + } + } +} |