implement wifi tethering

5 files changed, 329 insertions, 136 deletions

diff --git a/app/src/main/java/se/leap/bitmaskclient/firewall/ConfigureTetheringTask.java b/app/src/main/java/se/leap/bitmaskclient/firewall/ConfigureTetheringTask.java
deleted file mode 100644
index 3363152e..00000000
--- a/app/src/main/java/se/leap/bitmaskclient/firewall/ConfigureTetheringTask.java
+++ /dev/null
@@ -1,111 +0,0 @@
-/**
- * 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 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 ConfigureTetheringTask extends AsyncTask<TetheringState, Boolean, Boolean> {
-
-    private WeakReference<FirewallCallback> callbackWeakReference;
-
-    ConfigureTetheringTask(FirewallCallback callback) {
-        callbackWeakReference = new WeakReference<>(callback);
-    }
-
-    @Override
-    protected Boolean doInBackground(TetheringState... tetheringStates) {
-        TetheringState tetheringState = tetheringStates[0];
-        StringBuilder log = new StringBuilder();
-
-        String[] bitmaskChain = new String[]{
-                "su",
-                "id",
-                "iptables --list " + BITMASK_FORWARD + " && iptables --list " + BITMASK_POSTROUTING };
-
-        try {
-            boolean hasBitmaskChain = runBlockingCmd(bitmaskChain, log) == 0;
-            boolean allowSu = log.toString().contains("uid=0");
-            callbackWeakReference.get().onSuRequested(allowSu);
-            if (!allowSu) {
-                return false;
-            }
-
-            boolean success;
-            log = new StringBuilder();
-            if (hasAnyTetheringEnabled(tetheringState)) {
-                if (!hasBitmaskChain) {
-                    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());
-                }
-
-                String[] addRules = 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" };
-                return runBlockingCmd(addRules, log) == 0;
-            } else {
-                if (!hasBitmaskChain) return true;
-                String[] removeChains = new String[] {
-                        "su",
-                        "iptables -t filter --delete FORWARD --jump " + BITMASK_FORWARD,
-                        "iptables -t nat --delete POSTROUTING --jump " + BITMASK_POSTROUTING,
-                        "iptables -t filter --flush " + BITMASK_FORWARD,
-                        "iptables -t nat --flush " + BITMASK_POSTROUTING,
-                        "iptables -t filter --delete-chain " + BITMASK_FORWARD,
-                        "iptables -t nat --delete-chain " + BITMASK_POSTROUTING
-                };
-                return runBlockingCmd(removeChains, log) == 0;
-            }
-        } catch (Exception e) {
-            e.printStackTrace();
-            Log.e(FirewallManager.TAG, log.toString());
-        }
-        return false;
-    }
-
-    @Override
-    protected void onPostExecute(Boolean result) {
-        super.onPostExecute(result);
-        FirewallCallback callback = callbackWeakReference.get();
-        if (callback != null) {
-            callback.onTetheringConfigured(result);
-        }
-    }
-
-    private boolean hasAnyTetheringEnabled(TetheringState state) {
-        return state.isBluetoothTetheringEnabled || state.isUsbTetheringEnabled || state.isWifiTetheringEnabled;
-    }
-}
diff --git a/app/src/main/java/se/leap/bitmaskclient/firewall/FirewallCallback.java b/app/src/main/java/se/leap/bitmaskclient/firewall/FirewallCallback.java
index c6b3934c..15fa426f 100644
--- a/app/src/main/java/se/leap/bitmaskclient/firewall/FirewallCallback.java
+++ b/app/src/main/java/se/leap/bitmaskclient/firewall/FirewallCallback.java
@@ -19,6 +19,7 @@ package se.leap.bitmaskclient.firewall;
 interface FirewallCallback {
     void onFirewallStarted(boolean success);
     void onFirewallStopped(boolean success);
-    void onTetheringConfigured(boolean success);
+    void onTetheringStarted(boolean success);
+    void onTetheringStopped(boolean success);
     void onSuRequested(boolean success);
 }
diff --git a/app/src/main/java/se/leap/bitmaskclient/firewall/FirewallManager.java b/app/src/main/java/se/leap/bitmaskclient/firewall/FirewallManager.java
index 78166671..82888668 100644
--- a/app/src/main/java/se/leap/bitmaskclient/firewall/FirewallManager.java
+++ b/app/src/main/java/se/leap/bitmaskclient/firewall/FirewallManager.java
@@ -18,13 +18,15 @@ package se.leap.bitmaskclient.firewall;
 
 import android.content.Context;
 
+import java.util.Observable;
+import java.util.Observer;
+
 import de.blinkt.openvpn.core.VpnStatus;
 import se.leap.bitmaskclient.tethering.TetheringObservable;
 import se.leap.bitmaskclient.tethering.TetheringState;
 import se.leap.bitmaskclient.utils.PreferenceHelper;
 
-
-public class FirewallManager implements FirewallCallback {
+public class FirewallManager implements FirewallCallback, Observer {
     public static String BITMASK_CHAIN = "bitmask_fw";
     public static String BITMASK_FORWARD = "bitmask_forward";
     public static String BITMASK_POSTROUTING = "bitmask_postrouting";
@@ -32,11 +34,13 @@ public class FirewallManager implements FirewallCallback {
 
     private Context context;
 
-    public FirewallManager(Context context) {
+    public FirewallManager(Context context, boolean observeTethering) {
         this.context = context;
+        if (observeTethering) {
+            TetheringObservable.getInstance().addObserver(this);
+        }
     }
 
-
     @Override
     public void onFirewallStarted(boolean success) {
         if (success) {
@@ -56,11 +60,20 @@ public class FirewallManager implements FirewallCallback {
     }
 
     @Override
-    public void onTetheringConfigured(boolean success) {
+    public void onTetheringStarted(boolean success) {
+        if (success) {
+            VpnStatus.logInfo("[FIREWALL] Rules for tethering enabled");
+        } else {
+            VpnStatus.logError("[FIREWALL] Could not enable rules for tethering.");
+        }
+    }
+
+    @Override
+    public void onTetheringStopped(boolean success) {
         if (success) {
-            VpnStatus.logInfo("[FIREWALL] Rules for tethering configured");
+            VpnStatus.logInfo("[FIREWALL] Rules for tethering successfully disabled");
         } else {
-            VpnStatus.logError("[FIREWALL] Could not establish rules for tethering ");
+            VpnStatus.logError("[FIREWALL] Could not disable rules for tethering.");
         }
     }
 
@@ -72,30 +85,32 @@ public class FirewallManager implements FirewallCallback {
         }
     }
 
+    public void onDestroy() {
+        TetheringObservable.getInstance().deleteObserver(this);
+    }
+
 
     public void start() {
         startIPv6Firewall();
-        if (TetheringObservable.getInstance().hasAnyTetheringEnabled()) {
-            TetheringState deviceTethering = TetheringObservable.getInstance().getTetheringState();
-            TetheringState vpnTethering = new TetheringState();
-            vpnTethering.isWifiTetheringEnabled = deviceTethering.isWifiTetheringEnabled && PreferenceHelper.getWifiTethering(context);
-            vpnTethering.isUsbTetheringEnabled = deviceTethering.isUsbTetheringEnabled && PreferenceHelper.getUsbTethering(context);
-            vpnTethering.isBluetoothTetheringEnabled = deviceTethering.isBluetoothTetheringEnabled && PreferenceHelper.getBluetoothTethering(context);
-            configureTethering(vpnTethering);
+        TetheringState tetheringState = TetheringObservable.getInstance().getTetheringState();
+        if (tetheringState.hasAnyDeviceTetheringEnabled() && tetheringState.hasAnyVpnTetheringAllowed()) {
+            startTethering();
         }
     }
+
     public void stop() {
-        shutdownIPv6Firewall();
-        TetheringState allowedTethering = new TetheringState();
-        allowedTethering.isWifiTetheringEnabled = PreferenceHelper.getWifiTethering(context);
-        allowedTethering.isUsbTetheringEnabled = PreferenceHelper.getUsbTethering(context);
-        allowedTethering.isBluetoothTetheringEnabled = PreferenceHelper.getBluetoothTethering(context);
-        configureTethering(allowedTethering);
+        stopIPv6Firewall();
+        stopTethering();
+    }
+
+    public void startTethering() {
+        SetupTetheringTask task = new SetupTetheringTask(this);
+        task.execute();
     }
 
-    public void configureTethering(TetheringState state) {
-        ConfigureTetheringTask task = new ConfigureTetheringTask(this);
-        task.execute(state);
+    private void stopTethering() {
+        ShutdownTetheringTask task = new ShutdownTetheringTask(this);
+        task.execute();
     }
 
     private void startIPv6Firewall() {
@@ -103,9 +118,21 @@ public class FirewallManager implements FirewallCallback {
         task.execute();
     }
 
-    private void shutdownIPv6Firewall() {
+    private void stopIPv6Firewall() {
         ShutdownIPv6FirewallTask task = new ShutdownIPv6FirewallTask(this);
         task.execute();
     }
 
+    @Override
+    public void update(Observable o, Object arg) {
+        if (o instanceof TetheringObservable) {
+            TetheringObservable observable = (TetheringObservable) o;
+            TetheringState state = observable.getTetheringState();
+            if (state.hasAnyVpnTetheringAllowed() && state.hasAnyDeviceTetheringEnabled()) {
+                startTethering();
+            } else {
+                stopTethering();
+            }
+        }
+    }
 }
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..93054099
--- /dev/null
+++ b/app/src/main/java/se/leap/bitmaskclient/firewall/SetupTetheringTask.java
@@ -0,0 +1,187 @@
+/**
+ * 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.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");
+            callbackWeakReference.get().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);
+            } else if (!tetheringState.isVpnWifiTetheringAllowed){
+                success = removeWifiTetheringRules(tetheringState, log);
+            }
+
+            if (tetheringState.tetherUsbVpn()) {
+                success = success && addUsbTetheringRules(tetheringState, log);
+            } else if (!tetheringState.isVpnUsbTetheringAllowed) {
+                success = success && removeUsbTetheringRules(tetheringState, log);
+            }
+
+            if (tetheringState.tetherBluetoothVpn()) {
+                success = success && addBluetoothTetheringRules(tetheringState, log);
+            } else if (!tetheringState.isVpnBluetoothTetheringAllowed) {
+                success = success && removeBluetoothTetheringRules(tetheringState, log);
+            }
+            return success;
+        } catch (Exception e) {
+            e.printStackTrace();
+            Log.e(FirewallManager.TAG, log.toString());
+        }
+        return false;
+    }
+
+
+    //TODO: implement the follwing methods -v
+    private boolean removeBluetoothTetheringRules(TetheringState tetheringState, StringBuilder log) {
+        return true;
+    }
+
+    private boolean removeUsbTetheringRules(TetheringState tetheringState, StringBuilder log) {
+        return true;
+    }
+
+    private boolean addBluetoothTetheringRules(TetheringState tetheringState, StringBuilder log) {
+        return true;
+    }
+
+    private boolean addUsbTetheringRules(TetheringState tetheringState, StringBuilder log) {
+        return true;
+    }
+
+
+    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 = 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 "+ state.wifiAddress+" lookup 61` ]]; " +
+                        "then ip rule add from " + state.wifiAddress + " 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 '"+ state.wifiAddress+" dev "+ state.wifiInterface+" scope link'` ]]; " +
+                        "then ip route add " + state.wifiAddress + " dev " + state.wifiInterface + " scope link table 61; " +
+                        "fi",
+                "if [[ ! `ip route list table 61 | grep 'broadcast 255.255.255.255 dev " + state.wifiInterface + " scope link'` ]]; " +
+                        "then ip route add broadcast 255.255.255.255 dev " + state.wifiInterface + " scope link table 61; " +
+                        "fi"
+        };
+
+        return runBlockingCmd(addRules, log) == 0;
+    }
+
+    private boolean removeWifiTetheringRules(TetheringState state, StringBuilder log) throws Exception {
+        Log.d(TAG, "add Wifi tethering Rules");
+        String[] removeRules = new String[] {
+                "su",
+                "ip route delete broadcast 255.255.255.255 dev " + state.wifiInterface +" scope link table 61",
+                "ip route delete " + state.lastWifiAddress + " dev " + state.wifiInterface +" scope link table 61",
+                "ip route delete default dev " + getTunName() + " scope link table 61",
+                "if [[ `ip rule show from " + state.wifiAddress+ " lookup 61` ]]; " +
+                        "then ip rule del from " + state.wifiAddress + " lookup 61; " +
+                        "fi",
+        };
+        return runBlockingCmd(removeRules, log) == 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);
+        }
+    }
+}
diff --git a/app/src/main/java/se/leap/bitmaskclient/firewall/ShutdownTetheringTask.java b/app/src/main/java/se/leap/bitmaskclient/firewall/ShutdownTetheringTask.java
new file mode 100644
index 00000000..6c15c3e3
--- /dev/null
+++ b/app/src/main/java/se/leap/bitmaskclient/firewall/ShutdownTetheringTask.java
@@ -0,0 +1,89 @@
+/**
+ * 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 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 ShutdownTetheringTask extends AsyncTask<Void, Boolean, Boolean> {
+
+    private WeakReference<FirewallCallback> callbackWeakReference;
+
+    ShutdownTetheringTask(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");
+            callbackWeakReference.get().onSuRequested(allowSu);
+            if (!allowSu || !hasBitmaskChain) {
+                return false;
+            }
+
+            log = new StringBuilder();
+
+            String[] removeChains = new String[] {
+                    "su",
+                    "ip route flush table 61",
+                    "if [[ `ip rule show from " + tetheringState.wifiAddress+ " lookup 61` ]]; " +
+                            "then ip rule del from " + tetheringState.wifiAddress + " lookup 61; " +
+                            "fi",
+                    "iptables -t filter --delete FORWARD --jump " + BITMASK_FORWARD,
+                    "iptables -t nat --delete POSTROUTING --jump " + BITMASK_POSTROUTING,
+                    "iptables -t filter --flush " + BITMASK_FORWARD,
+                    "iptables -t nat --flush " + BITMASK_POSTROUTING,
+                    "iptables -t filter --delete-chain " + BITMASK_FORWARD,
+                    "iptables -t nat --delete-chain " + BITMASK_POSTROUTING,
+            };
+            return runBlockingCmd(removeChains, log) == 0;
+
+        } catch (Exception e) {
+            e.printStackTrace();
+            Log.e(FirewallManager.TAG, log.toString());
+        }
+        return false;
+    }
+
+    @Override
+    protected void onPostExecute(Boolean result) {
+        super.onPostExecute(result);
+        FirewallCallback callback = callbackWeakReference.get();
+        if (callback != null) {
+            callback.onTetheringStarted(result);
+        }
+    }
+}