Merge branch 'rooted_firewall' into 'master'

firewall

Closes #8939

See merge request leap/bitmask_android!96

6 files changed, 331 insertions, 32 deletions

diff --git a/app/src/main/java/de/blinkt/openvpn/core/OpenVPNService.java b/app/src/main/java/de/blinkt/openvpn/core/OpenVPNService.java
index 0863cc8e..766dc925 100644
--- a/app/src/main/java/de/blinkt/openvpn/core/OpenVPNService.java
+++ b/app/src/main/java/de/blinkt/openvpn/core/OpenVPNService.java
@@ -47,6 +47,7 @@ import de.blinkt.openvpn.core.connection.Obfs4Connection;
 import se.leap.bitmaskclient.R;
 import se.leap.bitmaskclient.VpnNotificationManager;
 import se.leap.bitmaskclient.pluggableTransports.Shapeshifter;
+import se.leap.bitmaskclient.utils.FirewallHelper;
 
 import static de.blinkt.openvpn.core.ConnectionStatus.LEVEL_CONNECTED;
 import static de.blinkt.openvpn.core.ConnectionStatus.LEVEL_WAITING_FOR_USER_INPUT;
@@ -89,6 +90,7 @@ public class OpenVPNService extends VpnService implements StateListener, Callbac
     private Runnable mOpenVPNThread;
     private VpnNotificationManager notificationManager;
     private Shapeshifter shapeshifter;
+    private FirewallHelper firewallHelper;
 
     private static final int PRIORITY_MIN = -2;
     private static final int PRIORITY_DEFAULT = 0;
@@ -192,6 +194,7 @@ public class OpenVPNService extends VpnService implements StateListener, Callbac
                 VpnStatus.removeStateListener(this);
             }
         }
+        firewallHelper.shutdownFirewall();
     }
 
     private boolean runningOnAndroidTV() {
@@ -446,6 +449,8 @@ public class OpenVPNService extends VpnService implements StateListener, Callbac
             mProcessThread.start();
         }
 
+        firewallHelper.startFirewall();
+
         new Handler(getMainLooper()).post(() -> {
             if (mDeviceStateReceiver != null) {
                 unregisterDeviceStateReceiver();
@@ -513,6 +518,7 @@ public class OpenVPNService extends VpnService implements StateListener, Callbac
         super.onCreate();
         notificationManager = new VpnNotificationManager(this, this);
         notificationManager.createOpenVpnNotificationChannel();
+        firewallHelper = new FirewallHelper(this);
     }
 
     @Override
diff --git a/app/src/main/java/se/leap/bitmaskclient/Constants.java b/app/src/main/java/se/leap/bitmaskclient/Constants.java
index d3c09f08..0cbf82e1 100644
--- a/app/src/main/java/se/leap/bitmaskclient/Constants.java
+++ b/app/src/main/java/se/leap/bitmaskclient/Constants.java
@@ -15,6 +15,7 @@ public interface Constants {
     String LAST_USED_PROFILE = "last_used_profile";
     String EXCLUDED_APPS = "excluded_apps";
     String USE_PLUGGABLE_TRANSPORTS = "usePluggableTransports";
+    String SU_PERMISSION = "su_permission";
 
 
      //////////////////////////////////////////////
diff --git a/app/src/main/java/se/leap/bitmaskclient/Provider.java b/app/src/main/java/se/leap/bitmaskclient/Provider.java
index 507a11bf..b98c3fd3 100644
--- a/app/src/main/java/se/leap/bitmaskclient/Provider.java
+++ b/app/src/main/java/se/leap/bitmaskclient/Provider.java
@@ -141,7 +141,7 @@ public final class Provider implements Parcelable {
                 }
             }
         } catch (Exception e) {
-           e.printStackTrace();
+           // ignore
         }
        return false;
     }
diff --git a/app/src/main/java/se/leap/bitmaskclient/utils/Cmd.java b/app/src/main/java/se/leap/bitmaskclient/utils/Cmd.java
new file mode 100644
index 00000000..a72658a4
--- /dev/null
+++ b/app/src/main/java/se/leap/bitmaskclient/utils/Cmd.java
@@ -0,0 +1,93 @@
+/**
+ * Copyright (c) 2019 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.utils;
+
+import android.support.annotation.WorkerThread;
+import android.util.Log;
+
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.io.OutputStreamWriter;
+
+public class Cmd {
+
+    private static final String TAG = Cmd.class.getSimpleName();
+
+    @WorkerThread
+    public static int runBlockingCmd(String[] cmds, StringBuilder log) throws Exception {
+        return runCmd(cmds, log, true);
+    }
+
+    @WorkerThread
+    private static int runCmd(String[] cmds, StringBuilder log,
+                       boolean waitFor) throws Exception {
+
+        int exitCode = -1;
+        Process proc = Runtime.getRuntime().exec("sh");
+        OutputStreamWriter out = new OutputStreamWriter(proc.getOutputStream());
+
+        try {
+            for (String cmd : cmds) {
+                Log.d(TAG, "executing CMD: " + cmd);
+                out.write(cmd);
+                out.write("\n");
+            }
+
+            out.flush();
+            out.write("exit\n");
+            out.flush();
+        } catch (IOException e) {
+            e.printStackTrace();
+        } finally {
+            out.close();
+        }
+
+        if (waitFor) {
+            // Consume the "stdout"
+            InputStreamReader reader = new InputStreamReader(proc.getInputStream());
+            readToLogString(reader, log);
+
+            // Consume the "stderr"
+            reader = new InputStreamReader(proc.getErrorStream());
+            readToLogString(reader, log);
+
+            try {
+                exitCode = proc.waitFor();
+            } catch (InterruptedException e) {
+                e.printStackTrace();
+            }
+        }
+
+        return exitCode;
+    }
+
+    private static void readToLogString(InputStreamReader reader, StringBuilder log) throws IOException {
+        final char buf[] = new char[10];
+        int read = 0;
+        try {
+            while ((read = reader.read(buf)) != -1) {
+                if (log != null)
+                    log.append(buf, 0, read);
+            }
+        } catch (IOException e) {
+            reader.close();
+            throw new IOException(e);
+        }
+        reader.close();
+    }
+}
diff --git a/app/src/main/java/se/leap/bitmaskclient/utils/FirewallHelper.java b/app/src/main/java/se/leap/bitmaskclient/utils/FirewallHelper.java
new file mode 100644
index 00000000..26e6603a
--- /dev/null
+++ b/app/src/main/java/se/leap/bitmaskclient/utils/FirewallHelper.java
@@ -0,0 +1,196 @@
+package se.leap.bitmaskclient.utils;
+/**
+ * Copyright (c) 2019 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/>.
+ */
+
+import android.content.Context;
+import android.os.AsyncTask;
+import android.util.Log;
+
+import java.lang.ref.WeakReference;
+
+import de.blinkt.openvpn.core.VpnStatus;
+
+import static se.leap.bitmaskclient.utils.Cmd.runBlockingCmd;
+
+interface FirewallCallback {
+    void onFirewallStarted(boolean success);
+    void onFirewallStopped(boolean success);
+    void onSuRequested(boolean success);
+}
+
+
+public class FirewallHelper implements FirewallCallback {
+    private static String BITMASK_CHAIN = "bitmask_fw";
+    private static final String TAG = FirewallHelper.class.getSimpleName();
+
+    private Context context;
+
+    public FirewallHelper(Context context) {
+        this.context = context;
+    }
+
+
+    @Override
+    public void onFirewallStarted(boolean success) {
+        if (success) {
+            VpnStatus.logInfo("[FIREWALL] Custom rules established");
+        } else {
+            VpnStatus.logError("[FIREWALL] Could not establish custom rules.");
+        }
+    }
+
+    @Override
+    public void onFirewallStopped(boolean success) {
+        if (success) {
+            VpnStatus.logInfo("[FIREWALL] Custom rules deleted");
+        } else {
+            VpnStatus.logError("[FIREWALL] Could not delete custom rules");
+        }
+    }
+
+    @Override
+    public void onSuRequested(boolean success) {
+        PreferenceHelper.setSuPermission(context, success);
+        if (!success) {
+            VpnStatus.logError("[FIREWALL] Root permission needed to execute custom firewall rules.");
+        }
+    }
+
+
+    private static class StartFirewallTask extends  AsyncTask<Void, Boolean, Boolean> {
+
+       WeakReference<FirewallCallback> callbackWeakReference;
+
+        StartFirewallTask(FirewallCallback callback) {
+            callbackWeakReference = new WeakReference<>(callback);
+        }
+
+        @Override
+        protected Boolean doInBackground(Void... voids) {
+            StringBuilder log = new StringBuilder();
+            String[] bitmaskChain = new String[]{
+                    "su",
+                    "id",
+                    "ip6tables --list " + BITMASK_CHAIN };
+
+
+            try {
+                boolean hasBitmaskChain = runBlockingCmd(bitmaskChain, log) == 0;
+                boolean allowSu = log.toString().contains("uid=0");
+                try {
+                    callbackWeakReference.get().onSuRequested(allowSu);
+                    Thread.sleep(1000);
+                } catch (Exception e) {
+                    //ignore
+                }
+
+                boolean success;
+                log = new StringBuilder();
+                if (!hasBitmaskChain) {
+                    String[] createChainAndRules = new String[]{
+                            "su",
+                            "ip6tables --new-chain " + BITMASK_CHAIN,
+                            "ip6tables --insert OUTPUT --jump " + BITMASK_CHAIN,
+                            "ip6tables --append " + BITMASK_CHAIN + " -p tcp --jump REJECT",
+                            "ip6tables --append " + BITMASK_CHAIN + " -p udp --jump REJECT"
+                    };
+                    success = runBlockingCmd(createChainAndRules, log) == 0;
+                    Log.d(TAG, "added " + BITMASK_CHAIN + " to ip6tables: " + success);
+                    Log.d(TAG, log.toString());
+                    return success;
+                } else {
+                    String[] addRules = new String[] {
+                            "su",
+                            "ip6tables --append " + BITMASK_CHAIN + " -p tcp --jump REJECT",
+                            "ip6tables --append " + BITMASK_CHAIN + " -p udp --jump REJECT" };
+                    return runBlockingCmd(addRules, log) == 0;
+                }
+            } catch (Exception e) {
+                e.printStackTrace();
+                Log.e(TAG, log.toString());
+            }
+            return false;
+        }
+
+        @Override
+        protected void onPostExecute(Boolean result) {
+            super.onPostExecute(result);
+            FirewallCallback callback = callbackWeakReference.get();
+            if (callback != null) {
+                callback.onFirewallStarted(result);
+            }
+        }
+    }
+
+    private static class ShutdownFirewallTask extends AsyncTask<Void, Boolean, Boolean> {
+
+        WeakReference<FirewallCallback> callbackWeakReference;
+
+        ShutdownFirewallTask(FirewallCallback callback) {
+            callbackWeakReference = new WeakReference<>(callback);
+        }
+
+        @Override
+        protected Boolean doInBackground(Void... voids) {
+            boolean success;
+            StringBuilder log = new StringBuilder();
+            String[] deleteChain = new String[]{
+                    "su",
+                    "id",
+                    "ip6tables --delete OUTPUT --jump " + BITMASK_CHAIN,
+                    "ip6tables --flush " + BITMASK_CHAIN,
+                    "ip6tables --delete-chain " + BITMASK_CHAIN
+            };
+            try {
+                success = runBlockingCmd(deleteChain, log) == 0;
+            } catch (Exception e) {
+                e.printStackTrace();
+                Log.e(TAG, log.toString());
+                return false;
+            }
+
+            try {
+                boolean allowSu = log.toString().contains("uid=0");
+                callbackWeakReference.get().onSuRequested(allowSu);
+            } catch (Exception e) {
+                //ignore
+            }
+            return success;
+        }
+
+        @Override
+        protected void onPostExecute(Boolean result) {
+            super.onPostExecute(result);
+            FirewallCallback callback = callbackWeakReference.get();
+            if (callback != null) {
+                callback.onFirewallStopped(result);
+            }
+        }
+    }
+
+
+    public void startFirewall() {
+        StartFirewallTask task = new StartFirewallTask(this);
+        task.execute();
+    }
+
+    public void shutdownFirewall() {
+        ShutdownFirewallTask task = new ShutdownFirewallTask(this);
+        task.execute();
+    }
+
+}
diff --git a/app/src/main/java/se/leap/bitmaskclient/utils/PreferenceHelper.java b/app/src/main/java/se/leap/bitmaskclient/utils/PreferenceHelper.java
index 9eac7187..40bb2eca 100644
--- a/app/src/main/java/se/leap/bitmaskclient/utils/PreferenceHelper.java
+++ b/app/src/main/java/se/leap/bitmaskclient/utils/PreferenceHelper.java
@@ -31,6 +31,7 @@ import static se.leap.bitmaskclient.Constants.PROVIDER_EIP_DEFINITION;
 import static se.leap.bitmaskclient.Constants.PROVIDER_PRIVATE_KEY;
 import static se.leap.bitmaskclient.Constants.PROVIDER_VPN_CERTIFICATE;
 import static se.leap.bitmaskclient.Constants.SHARED_PREFERENCES;
+import static se.leap.bitmaskclient.Constants.SU_PERMISSION;
 import static se.leap.bitmaskclient.Constants.USE_PLUGGABLE_TRANSPORTS;
 import static se.leap.bitmaskclient.Constants.EXCLUDED_APPS;
 
@@ -214,52 +215,36 @@ public class PreferenceHelper {
                 apply();
     }
 
+    public static boolean hasSuPermission(Context context) {
+        return getBoolean(context, SU_PERMISSION, false);
+    }
+
+    public static void setSuPermission(Context context, boolean allowed) {
+        putBoolean(context, SU_PERMISSION, allowed);
+    }
+
     public static boolean getUsePluggableTransports(Context context) {
-        if (context == null) {
-            return false;
-        }
-        SharedPreferences preferences = context.getSharedPreferences(SHARED_PREFERENCES, MODE_PRIVATE);
-        return preferences.getBoolean(USE_PLUGGABLE_TRANSPORTS, false);
+        return getBoolean(context, USE_PLUGGABLE_TRANSPORTS, false);
     }
 
     public static void usePluggableTransports(Context context, boolean isEnabled) {
-        if (context == null) {
-            return;
-        }
-        SharedPreferences preferences = context.getSharedPreferences(SHARED_PREFERENCES, MODE_PRIVATE);
-        preferences.edit().putBoolean(USE_PLUGGABLE_TRANSPORTS, isEnabled).apply();
+        putBoolean(context, USE_PLUGGABLE_TRANSPORTS, isEnabled);
     }
 
     public static void saveBattery(Context context, boolean isEnabled) {
-        if (context == null) {
-            return;
-        }
-        SharedPreferences preferences = context.getSharedPreferences(SHARED_PREFERENCES, MODE_PRIVATE);
-        preferences.edit().putBoolean(DEFAULT_SHARED_PREFS_BATTERY_SAVER, isEnabled).apply();
+        putBoolean(context, DEFAULT_SHARED_PREFS_BATTERY_SAVER, isEnabled);
     }
 
     public static boolean getSaveBattery(Context context) {
-        if (context == null) {
-            return false;
-        }
-        SharedPreferences preferences = context.getSharedPreferences(SHARED_PREFERENCES, MODE_PRIVATE);
-        return preferences.getBoolean(DEFAULT_SHARED_PREFS_BATTERY_SAVER, false);
+        return getBoolean(context, DEFAULT_SHARED_PREFS_BATTERY_SAVER, false);
     }
 
     public static void saveShowAlwaysOnDialog(Context context, boolean showAlwaysOnDialog) {
-        if (context == null) {
-            return;
-        }
-        SharedPreferences preferences = context.getSharedPreferences(SHARED_PREFERENCES, MODE_PRIVATE);
-        preferences.edit().putBoolean(ALWAYS_ON_SHOW_DIALOG, showAlwaysOnDialog).apply();
+        putBoolean(context, ALWAYS_ON_SHOW_DIALOG, showAlwaysOnDialog);
     }
 
     public static boolean getShowAlwaysOnDialog(Context context) {
-        if (context == null) {
-            return true;
-        }
-        SharedPreferences preferences = context.getSharedPreferences(SHARED_PREFERENCES, MODE_PRIVATE);
-        return preferences.getBoolean(ALWAYS_ON_SHOW_DIALOG, true);
+        return getBoolean(context, ALWAYS_ON_SHOW_DIALOG, true);
     }
 
     public static JSONObject getEipDefinitionFromPreferences(SharedPreferences preferences) {
@@ -296,9 +281,27 @@ public class PreferenceHelper {
         return preferences.getString(key, defValue);
     }
 
-    public static void putString(Context context, String key, String value){
+    public static void putString(Context context, String key, String value) {
         SharedPreferences preferences = context.getSharedPreferences(SHARED_PREFERENCES, MODE_PRIVATE);
         preferences.edit().putString(key, value).apply();
     }
 
+    public static Boolean getBoolean(Context context, String key, Boolean defValue) {
+        if (context == null) {
+            return false;
+        }
+
+        SharedPreferences preferences = context.getSharedPreferences(SHARED_PREFERENCES, MODE_PRIVATE);
+        return preferences.getBoolean(key, defValue);
+    }
+
+    public static void putBoolean(Context context, String key, Boolean value) {
+        if (context == null) {
+            return;
+        }
+
+        SharedPreferences preferences = context.getSharedPreferences(SHARED_PREFERENCES, MODE_PRIVATE);
+        preferences.edit().putBoolean(key, value).apply();
+    }
+
 }