| /* |
| * Copyright (C) 2012 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. |
| */ |
| |
| package com.android.server.adb; |
| |
| import static com.android.internal.util.dump.DumpUtils.writeStringIfNotNull; |
| |
| import android.annotation.TestApi; |
| import android.app.ActivityManager; |
| import android.content.ActivityNotFoundException; |
| import android.content.ComponentName; |
| import android.content.Context; |
| import android.content.Intent; |
| import android.content.pm.PackageManager; |
| import android.content.pm.UserInfo; |
| import android.content.res.Resources; |
| import android.database.ContentObserver; |
| import android.debug.AdbProtoEnums; |
| import android.net.LocalSocket; |
| import android.net.LocalSocketAddress; |
| import android.net.Uri; |
| import android.os.Environment; |
| import android.os.FileUtils; |
| import android.os.Handler; |
| import android.os.Looper; |
| import android.os.Message; |
| import android.os.SystemClock; |
| import android.os.SystemProperties; |
| import android.os.UserHandle; |
| import android.os.UserManager; |
| import android.provider.Settings; |
| import android.service.adb.AdbDebuggingManagerProto; |
| import android.util.AtomicFile; |
| import android.util.Base64; |
| import android.util.Slog; |
| import android.util.StatsLog; |
| import android.util.Xml; |
| |
| import com.android.internal.R; |
| import com.android.internal.annotations.VisibleForTesting; |
| import com.android.internal.util.FastXmlSerializer; |
| import com.android.internal.util.XmlUtils; |
| import com.android.internal.util.dump.DualDumpOutputStream; |
| import com.android.server.FgThread; |
| |
| import org.xmlpull.v1.XmlPullParser; |
| import org.xmlpull.v1.XmlPullParserException; |
| import org.xmlpull.v1.XmlSerializer; |
| |
| import java.io.BufferedReader; |
| import java.io.File; |
| import java.io.FileInputStream; |
| import java.io.FileOutputStream; |
| import java.io.FileReader; |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.io.OutputStream; |
| import java.nio.charset.StandardCharsets; |
| import java.security.MessageDigest; |
| import java.util.ArrayList; |
| import java.util.Arrays; |
| import java.util.HashMap; |
| import java.util.HashSet; |
| import java.util.Iterator; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.Set; |
| |
| /** |
| * Provides communication to the Android Debug Bridge daemon to allow, deny, or clear public keysi |
| * that are authorized to connect to the ADB service itself. |
| */ |
| public class AdbDebuggingManager { |
| private static final String TAG = "AdbDebuggingManager"; |
| private static final boolean DEBUG = false; |
| |
| private static final String ADBD_SOCKET = "adbd"; |
| private static final String ADB_DIRECTORY = "misc/adb"; |
| // This file contains keys that will always be allowed to connect to the device via adb. |
| private static final String ADB_KEYS_FILE = "adb_keys"; |
| // This file contains keys that will be allowed to connect without user interaction as long |
| // as a subsequent connection occurs within the allowed duration. |
| private static final String ADB_TEMP_KEYS_FILE = "adb_temp_keys.xml"; |
| private static final int BUFFER_SIZE = 65536; |
| |
| private final Context mContext; |
| private final Handler mHandler; |
| private AdbDebuggingThread mThread; |
| private boolean mAdbEnabled = false; |
| private String mFingerprints; |
| private final List<String> mConnectedKeys; |
| private String mConfirmComponent; |
| private final File mTestUserKeyFile; |
| |
| public AdbDebuggingManager(Context context) { |
| mHandler = new AdbDebuggingHandler(FgThread.get().getLooper()); |
| mContext = context; |
| mTestUserKeyFile = null; |
| mConnectedKeys = new ArrayList<>(1); |
| } |
| |
| /** |
| * Constructor that accepts the component to be invoked to confirm if the user wants to allow |
| * an adb connection from the key. |
| */ |
| @TestApi |
| protected AdbDebuggingManager(Context context, String confirmComponent, File testUserKeyFile) { |
| mHandler = new AdbDebuggingHandler(FgThread.get().getLooper()); |
| mContext = context; |
| mConfirmComponent = confirmComponent; |
| mTestUserKeyFile = testUserKeyFile; |
| mConnectedKeys = new ArrayList<>(); |
| } |
| |
| class AdbDebuggingThread extends Thread { |
| private boolean mStopped; |
| private LocalSocket mSocket; |
| private OutputStream mOutputStream; |
| private InputStream mInputStream; |
| |
| AdbDebuggingThread() { |
| super(TAG); |
| } |
| |
| @Override |
| public void run() { |
| if (DEBUG) Slog.d(TAG, "Entering thread"); |
| while (true) { |
| synchronized (this) { |
| if (mStopped) { |
| if (DEBUG) Slog.d(TAG, "Exiting thread"); |
| return; |
| } |
| try { |
| openSocketLocked(); |
| } catch (Exception e) { |
| /* Don't loop too fast if adbd dies, before init restarts it */ |
| SystemClock.sleep(1000); |
| } |
| } |
| try { |
| listenToSocket(); |
| } catch (Exception e) { |
| /* Don't loop too fast if adbd dies, before init restarts it */ |
| SystemClock.sleep(1000); |
| } |
| } |
| } |
| |
| private void openSocketLocked() throws IOException { |
| try { |
| LocalSocketAddress address = new LocalSocketAddress(ADBD_SOCKET, |
| LocalSocketAddress.Namespace.RESERVED); |
| mInputStream = null; |
| |
| if (DEBUG) Slog.d(TAG, "Creating socket"); |
| mSocket = new LocalSocket(LocalSocket.SOCKET_SEQPACKET); |
| mSocket.connect(address); |
| |
| mOutputStream = mSocket.getOutputStream(); |
| mInputStream = mSocket.getInputStream(); |
| } catch (IOException ioe) { |
| Slog.e(TAG, "Caught an exception opening the socket: " + ioe); |
| closeSocketLocked(); |
| throw ioe; |
| } |
| } |
| |
| private void listenToSocket() throws IOException { |
| try { |
| byte[] buffer = new byte[BUFFER_SIZE]; |
| while (true) { |
| int count = mInputStream.read(buffer); |
| // if less than 2 bytes are read the if statements below will throw an |
| // IndexOutOfBoundsException. |
| if (count < 2) { |
| Slog.w(TAG, "Read failed with count " + count); |
| break; |
| } |
| |
| if (buffer[0] == 'P' && buffer[1] == 'K') { |
| String key = new String(Arrays.copyOfRange(buffer, 2, count)); |
| Slog.d(TAG, "Received public key: " + key); |
| Message msg = mHandler.obtainMessage( |
| AdbDebuggingHandler.MESSAGE_ADB_CONFIRM); |
| msg.obj = key; |
| mHandler.sendMessage(msg); |
| } else if (buffer[0] == 'D' && buffer[1] == 'C') { |
| String key = new String(Arrays.copyOfRange(buffer, 2, count)); |
| Slog.d(TAG, "Received disconnected message: " + key); |
| Message msg = mHandler.obtainMessage( |
| AdbDebuggingHandler.MESSAGE_ADB_DISCONNECT); |
| msg.obj = key; |
| mHandler.sendMessage(msg); |
| } else if (buffer[0] == 'C' && buffer[1] == 'K') { |
| String key = new String(Arrays.copyOfRange(buffer, 2, count)); |
| Slog.d(TAG, "Received connected key message: " + key); |
| Message msg = mHandler.obtainMessage( |
| AdbDebuggingHandler.MESSAGE_ADB_CONNECTED_KEY); |
| msg.obj = key; |
| mHandler.sendMessage(msg); |
| } else { |
| Slog.e(TAG, "Wrong message: " |
| + (new String(Arrays.copyOfRange(buffer, 0, 2)))); |
| break; |
| } |
| } |
| } finally { |
| synchronized (this) { |
| closeSocketLocked(); |
| } |
| } |
| } |
| |
| private void closeSocketLocked() { |
| if (DEBUG) Slog.d(TAG, "Closing socket"); |
| try { |
| if (mOutputStream != null) { |
| mOutputStream.close(); |
| mOutputStream = null; |
| } |
| } catch (IOException e) { |
| Slog.e(TAG, "Failed closing output stream: " + e); |
| } |
| |
| try { |
| if (mSocket != null) { |
| mSocket.close(); |
| mSocket = null; |
| } |
| } catch (IOException ex) { |
| Slog.e(TAG, "Failed closing socket: " + ex); |
| } |
| } |
| |
| /** Call to stop listening on the socket and exit the thread. */ |
| void stopListening() { |
| synchronized (this) { |
| mStopped = true; |
| closeSocketLocked(); |
| } |
| } |
| |
| void sendResponse(String msg) { |
| synchronized (this) { |
| if (!mStopped && mOutputStream != null) { |
| try { |
| mOutputStream.write(msg.getBytes()); |
| } catch (IOException ex) { |
| Slog.e(TAG, "Failed to write response:", ex); |
| } |
| } |
| } |
| } |
| } |
| |
| class AdbDebuggingHandler extends Handler { |
| // The default time to schedule the job to keep the keystore updated with a currently |
| // connected key as well as to removed expired keys. |
| static final long UPDATE_KEYSTORE_JOB_INTERVAL = 86400000; |
| // The minimum interval at which the job should run to update the keystore. This is intended |
| // to prevent the job from running too often if the allowed connection time for adb grants |
| // is set to an extremely small value. |
| static final long UPDATE_KEYSTORE_MIN_JOB_INTERVAL = 60000; |
| |
| static final int MESSAGE_ADB_ENABLED = 1; |
| static final int MESSAGE_ADB_DISABLED = 2; |
| static final int MESSAGE_ADB_ALLOW = 3; |
| static final int MESSAGE_ADB_DENY = 4; |
| static final int MESSAGE_ADB_CONFIRM = 5; |
| static final int MESSAGE_ADB_CLEAR = 6; |
| static final int MESSAGE_ADB_DISCONNECT = 7; |
| static final int MESSAGE_ADB_PERSIST_KEYSTORE = 8; |
| static final int MESSAGE_ADB_UPDATE_KEYSTORE = 9; |
| static final int MESSAGE_ADB_CONNECTED_KEY = 10; |
| |
| private AdbKeyStore mAdbKeyStore; |
| |
| private ContentObserver mAuthTimeObserver = new ContentObserver(this) { |
| @Override |
| public void onChange(boolean selfChange, Uri uri) { |
| Slog.d(TAG, "Received notification that uri " + uri |
| + " was modified; rescheduling keystore job"); |
| scheduleJobToUpdateAdbKeyStore(); |
| } |
| }; |
| |
| AdbDebuggingHandler(Looper looper) { |
| super(looper); |
| } |
| |
| /** |
| * Constructor that accepts the AdbDebuggingThread to which responses should be sent |
| * and the AdbKeyStore to be used to store the temporary grants. |
| */ |
| @TestApi |
| AdbDebuggingHandler(Looper looper, AdbDebuggingThread thread, AdbKeyStore adbKeyStore) { |
| super(looper); |
| mThread = thread; |
| mAdbKeyStore = adbKeyStore; |
| } |
| |
| public void handleMessage(Message msg) { |
| switch (msg.what) { |
| case MESSAGE_ADB_ENABLED: |
| if (mAdbEnabled) { |
| break; |
| } |
| registerForAuthTimeChanges(); |
| mAdbEnabled = true; |
| |
| mThread = new AdbDebuggingThread(); |
| mThread.start(); |
| |
| mAdbKeyStore = new AdbKeyStore(); |
| mAdbKeyStore.updateKeyStore(); |
| scheduleJobToUpdateAdbKeyStore(); |
| break; |
| |
| case MESSAGE_ADB_DISABLED: |
| if (!mAdbEnabled) { |
| break; |
| } |
| |
| mAdbEnabled = false; |
| |
| if (mThread != null) { |
| mThread.stopListening(); |
| mThread = null; |
| } |
| |
| if (!mConnectedKeys.isEmpty()) { |
| for (String connectedKey : mConnectedKeys) { |
| mAdbKeyStore.setLastConnectionTime(connectedKey, |
| System.currentTimeMillis()); |
| } |
| sendPersistKeyStoreMessage(); |
| mConnectedKeys.clear(); |
| } |
| scheduleJobToUpdateAdbKeyStore(); |
| break; |
| |
| case MESSAGE_ADB_ALLOW: { |
| String key = (String) msg.obj; |
| String fingerprints = getFingerprints(key); |
| if (!fingerprints.equals(mFingerprints)) { |
| Slog.e(TAG, "Fingerprints do not match. Got " |
| + fingerprints + ", expected " + mFingerprints); |
| break; |
| } |
| |
| boolean alwaysAllow = msg.arg1 == 1; |
| if (mThread != null) { |
| mThread.sendResponse("OK"); |
| if (alwaysAllow) { |
| if (!mConnectedKeys.contains(key)) { |
| mConnectedKeys.add(key); |
| } |
| mAdbKeyStore.setLastConnectionTime(key, System.currentTimeMillis()); |
| sendPersistKeyStoreMessage(); |
| scheduleJobToUpdateAdbKeyStore(); |
| } |
| logAdbConnectionChanged(key, AdbProtoEnums.USER_ALLOWED, alwaysAllow); |
| } |
| break; |
| } |
| |
| case MESSAGE_ADB_DENY: |
| if (mThread != null) { |
| mThread.sendResponse("NO"); |
| logAdbConnectionChanged(null, AdbProtoEnums.USER_DENIED, false); |
| } |
| break; |
| |
| case MESSAGE_ADB_CONFIRM: { |
| String key = (String) msg.obj; |
| if ("trigger_restart_min_framework".equals( |
| SystemProperties.get("vold.decrypt"))) { |
| Slog.d(TAG, "Deferring adb confirmation until after vold decrypt"); |
| if (mThread != null) { |
| mThread.sendResponse("NO"); |
| logAdbConnectionChanged(key, AdbProtoEnums.DENIED_VOLD_DECRYPT, false); |
| } |
| break; |
| } |
| String fingerprints = getFingerprints(key); |
| if ("".equals(fingerprints)) { |
| if (mThread != null) { |
| mThread.sendResponse("NO"); |
| logAdbConnectionChanged(key, AdbProtoEnums.DENIED_INVALID_KEY, false); |
| } |
| break; |
| } |
| logAdbConnectionChanged(key, AdbProtoEnums.AWAITING_USER_APPROVAL, false); |
| mFingerprints = fingerprints; |
| startConfirmation(key, mFingerprints); |
| break; |
| } |
| |
| case MESSAGE_ADB_CLEAR: { |
| Slog.d(TAG, "Received a request to clear the adb authorizations"); |
| mConnectedKeys.clear(); |
| mAdbKeyStore.deleteKeyStore(); |
| cancelJobToUpdateAdbKeyStore(); |
| break; |
| } |
| |
| case MESSAGE_ADB_DISCONNECT: { |
| String key = (String) msg.obj; |
| boolean alwaysAllow = false; |
| if (key != null && key.length() > 0) { |
| if (mConnectedKeys.contains(key)) { |
| alwaysAllow = true; |
| mAdbKeyStore.setLastConnectionTime(key, System.currentTimeMillis()); |
| sendPersistKeyStoreMessage(); |
| scheduleJobToUpdateAdbKeyStore(); |
| mConnectedKeys.remove(key); |
| } |
| } else { |
| Slog.w(TAG, "Received a disconnected key message with an empty key"); |
| } |
| logAdbConnectionChanged(key, AdbProtoEnums.DISCONNECTED, alwaysAllow); |
| break; |
| } |
| |
| case MESSAGE_ADB_PERSIST_KEYSTORE: { |
| if (mAdbKeyStore != null) { |
| mAdbKeyStore.persistKeyStore(); |
| } |
| break; |
| } |
| |
| case MESSAGE_ADB_UPDATE_KEYSTORE: { |
| if (!mConnectedKeys.isEmpty()) { |
| for (String connectedKey : mConnectedKeys) { |
| mAdbKeyStore.setLastConnectionTime(connectedKey, |
| System.currentTimeMillis()); |
| } |
| sendPersistKeyStoreMessage(); |
| scheduleJobToUpdateAdbKeyStore(); |
| } else if (!mAdbKeyStore.isEmpty()) { |
| mAdbKeyStore.updateKeyStore(); |
| scheduleJobToUpdateAdbKeyStore(); |
| } |
| break; |
| } |
| |
| case MESSAGE_ADB_CONNECTED_KEY: { |
| String key = (String) msg.obj; |
| if (key == null || key.length() == 0) { |
| Slog.w(TAG, "Received a connected key message with an empty key"); |
| } else { |
| if (!mConnectedKeys.contains(key)) { |
| mConnectedKeys.add(key); |
| } |
| mAdbKeyStore.setLastConnectionTime(key, System.currentTimeMillis()); |
| sendPersistKeyStoreMessage(); |
| scheduleJobToUpdateAdbKeyStore(); |
| logAdbConnectionChanged(key, AdbProtoEnums.AUTOMATICALLY_ALLOWED, true); |
| } |
| break; |
| } |
| } |
| } |
| |
| void registerForAuthTimeChanges() { |
| Uri uri = Settings.Global.getUriFor(Settings.Global.ADB_ALLOWED_CONNECTION_TIME); |
| mContext.getContentResolver().registerContentObserver(uri, false, mAuthTimeObserver); |
| } |
| |
| private void logAdbConnectionChanged(String key, int state, boolean alwaysAllow) { |
| long lastConnectionTime = mAdbKeyStore.getLastConnectionTime(key); |
| long authWindow = mAdbKeyStore.getAllowedConnectionTime(); |
| Slog.d(TAG, |
| "Logging key " + key + ", state = " + state + ", alwaysAllow = " + alwaysAllow |
| + ", lastConnectionTime = " + lastConnectionTime + ", authWindow = " |
| + authWindow); |
| StatsLog.write(StatsLog.ADB_CONNECTION_CHANGED, lastConnectionTime, authWindow, state, |
| alwaysAllow); |
| } |
| |
| |
| /** |
| * Schedules a job to update the connection time of the currently connected key and filter |
| * out any keys that are beyond their expiration time. |
| * |
| * @return the time in ms when the next job will run or -1 if the job should not be |
| * scheduled to run. |
| */ |
| @VisibleForTesting |
| long scheduleJobToUpdateAdbKeyStore() { |
| cancelJobToUpdateAdbKeyStore(); |
| long keyExpiration = mAdbKeyStore.getNextExpirationTime(); |
| // if the keyExpiration time is -1 then either the keys are set to never expire or |
| // there are no keys in the keystore, just return for now as a new job will be |
| // scheduled on the next connection or when the auth time changes. |
| if (keyExpiration == -1) { |
| return -1; |
| } |
| long delay; |
| // if the keyExpiration is 0 this indicates a key has already expired; schedule the job |
| // to run now to ensure the key is removed immediately from adb_keys. |
| if (keyExpiration == 0) { |
| delay = 0; |
| } else { |
| // else the next job should be run either daily or when the next key is set to |
| // expire with a min job interval to ensure this job does not run too often if a |
| // small value is set for the key expiration. |
| delay = Math.max(Math.min(UPDATE_KEYSTORE_JOB_INTERVAL, keyExpiration), |
| UPDATE_KEYSTORE_MIN_JOB_INTERVAL); |
| } |
| Message message = obtainMessage(MESSAGE_ADB_UPDATE_KEYSTORE); |
| sendMessageDelayed(message, delay); |
| return delay; |
| } |
| |
| /** |
| * Cancels the scheduled job to update the connection time of the currently connected key |
| * and to remove any expired keys. |
| */ |
| private void cancelJobToUpdateAdbKeyStore() { |
| removeMessages(AdbDebuggingHandler.MESSAGE_ADB_UPDATE_KEYSTORE); |
| } |
| } |
| |
| private String getFingerprints(String key) { |
| String hex = "0123456789ABCDEF"; |
| StringBuilder sb = new StringBuilder(); |
| MessageDigest digester; |
| |
| if (key == null) { |
| return ""; |
| } |
| |
| try { |
| digester = MessageDigest.getInstance("MD5"); |
| } catch (Exception ex) { |
| Slog.e(TAG, "Error getting digester", ex); |
| return ""; |
| } |
| |
| byte[] base64_data = key.split("\\s+")[0].getBytes(); |
| byte[] digest; |
| try { |
| digest = digester.digest(Base64.decode(base64_data, Base64.DEFAULT)); |
| } catch (IllegalArgumentException e) { |
| Slog.e(TAG, "error doing base64 decoding", e); |
| return ""; |
| } |
| for (int i = 0; i < digest.length; i++) { |
| sb.append(hex.charAt((digest[i] >> 4) & 0xf)); |
| sb.append(hex.charAt(digest[i] & 0xf)); |
| if (i < digest.length - 1) { |
| sb.append(":"); |
| } |
| } |
| return sb.toString(); |
| } |
| |
| private void startConfirmation(String key, String fingerprints) { |
| int currentUserId = ActivityManager.getCurrentUser(); |
| UserInfo userInfo = UserManager.get(mContext).getUserInfo(currentUserId); |
| String componentString; |
| if (userInfo.isAdmin()) { |
| componentString = mConfirmComponent != null |
| ? mConfirmComponent : Resources.getSystem().getString( |
| com.android.internal.R.string.config_customAdbPublicKeyConfirmationComponent); |
| } else { |
| // If the current foreground user is not the admin user we send a different |
| // notification specific to secondary users. |
| componentString = Resources.getSystem().getString( |
| R.string.config_customAdbPublicKeyConfirmationSecondaryUserComponent); |
| } |
| ComponentName componentName = ComponentName.unflattenFromString(componentString); |
| if (startConfirmationActivity(componentName, userInfo.getUserHandle(), key, fingerprints) |
| || startConfirmationService(componentName, userInfo.getUserHandle(), |
| key, fingerprints)) { |
| return; |
| } |
| Slog.e(TAG, "unable to start customAdbPublicKeyConfirmation[SecondaryUser]Component " |
| + componentString + " as an Activity or a Service"); |
| } |
| |
| /** |
| * @return true if the componentName led to an Activity that was started. |
| */ |
| private boolean startConfirmationActivity(ComponentName componentName, UserHandle userHandle, |
| String key, String fingerprints) { |
| PackageManager packageManager = mContext.getPackageManager(); |
| Intent intent = createConfirmationIntent(componentName, key, fingerprints); |
| intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK); |
| if (packageManager.resolveActivity(intent, PackageManager.MATCH_DEFAULT_ONLY) != null) { |
| try { |
| mContext.startActivityAsUser(intent, userHandle); |
| return true; |
| } catch (ActivityNotFoundException e) { |
| Slog.e(TAG, "unable to start adb whitelist activity: " + componentName, e); |
| } |
| } |
| return false; |
| } |
| |
| /** |
| * @return true if the componentName led to a Service that was started. |
| */ |
| private boolean startConfirmationService(ComponentName componentName, UserHandle userHandle, |
| String key, String fingerprints) { |
| Intent intent = createConfirmationIntent(componentName, key, fingerprints); |
| try { |
| if (mContext.startServiceAsUser(intent, userHandle) != null) { |
| return true; |
| } |
| } catch (SecurityException e) { |
| Slog.e(TAG, "unable to start adb whitelist service: " + componentName, e); |
| } |
| return false; |
| } |
| |
| private Intent createConfirmationIntent(ComponentName componentName, String key, |
| String fingerprints) { |
| Intent intent = new Intent(); |
| intent.setClassName(componentName.getPackageName(), componentName.getClassName()); |
| intent.putExtra("key", key); |
| intent.putExtra("fingerprints", fingerprints); |
| return intent; |
| } |
| |
| /** |
| * Returns a new File with the specified name in the adb directory. |
| */ |
| private File getAdbFile(String fileName) { |
| File dataDir = Environment.getDataDirectory(); |
| File adbDir = new File(dataDir, ADB_DIRECTORY); |
| |
| if (!adbDir.exists()) { |
| Slog.e(TAG, "ADB data directory does not exist"); |
| return null; |
| } |
| |
| return new File(adbDir, fileName); |
| } |
| |
| File getAdbTempKeysFile() { |
| return getAdbFile(ADB_TEMP_KEYS_FILE); |
| } |
| |
| File getUserKeyFile() { |
| return mTestUserKeyFile == null ? getAdbFile(ADB_KEYS_FILE) : mTestUserKeyFile; |
| } |
| |
| private void writeKey(String key) { |
| try { |
| File keyFile = getUserKeyFile(); |
| |
| if (keyFile == null) { |
| return; |
| } |
| |
| FileOutputStream fo = new FileOutputStream(keyFile, true); |
| fo.write(key.getBytes()); |
| fo.write('\n'); |
| fo.close(); |
| |
| FileUtils.setPermissions(keyFile.toString(), |
| FileUtils.S_IRUSR | FileUtils.S_IWUSR | FileUtils.S_IRGRP, -1, -1); |
| } catch (IOException ex) { |
| Slog.e(TAG, "Error writing key:" + ex); |
| } |
| } |
| |
| private void writeKeys(Iterable<String> keys) { |
| AtomicFile atomicKeyFile = null; |
| FileOutputStream fo = null; |
| try { |
| File keyFile = getUserKeyFile(); |
| |
| if (keyFile == null) { |
| return; |
| } |
| |
| atomicKeyFile = new AtomicFile(keyFile); |
| fo = atomicKeyFile.startWrite(); |
| for (String key : keys) { |
| fo.write(key.getBytes()); |
| fo.write('\n'); |
| } |
| atomicKeyFile.finishWrite(fo); |
| |
| FileUtils.setPermissions(keyFile.toString(), |
| FileUtils.S_IRUSR | FileUtils.S_IWUSR | FileUtils.S_IRGRP, -1, -1); |
| } catch (IOException ex) { |
| Slog.e(TAG, "Error writing keys: " + ex); |
| if (atomicKeyFile != null) { |
| atomicKeyFile.failWrite(fo); |
| } |
| } |
| } |
| |
| private void deleteKeyFile() { |
| File keyFile = getUserKeyFile(); |
| if (keyFile != null) { |
| keyFile.delete(); |
| } |
| } |
| |
| /** |
| * When {@code enabled} is {@code true}, this allows ADB debugging and starts the ADB hanler |
| * thread. When {@code enabled} is {@code false}, this disallows ADB debugging and shuts |
| * down the handler thread. |
| */ |
| public void setAdbEnabled(boolean enabled) { |
| mHandler.sendEmptyMessage(enabled ? AdbDebuggingHandler.MESSAGE_ADB_ENABLED |
| : AdbDebuggingHandler.MESSAGE_ADB_DISABLED); |
| } |
| |
| /** |
| * Allows the debugging from the endpoint identified by {@code publicKey} either once or |
| * always if {@code alwaysAllow} is {@code true}. |
| */ |
| public void allowDebugging(boolean alwaysAllow, String publicKey) { |
| Message msg = mHandler.obtainMessage(AdbDebuggingHandler.MESSAGE_ADB_ALLOW); |
| msg.arg1 = alwaysAllow ? 1 : 0; |
| msg.obj = publicKey; |
| mHandler.sendMessage(msg); |
| } |
| |
| /** |
| * Denies debugging connection from the device that last requested to connect. |
| */ |
| public void denyDebugging() { |
| mHandler.sendEmptyMessage(AdbDebuggingHandler.MESSAGE_ADB_DENY); |
| } |
| |
| /** |
| * Clears all previously accepted ADB debugging public keys. Any subsequent request will need |
| * to pass through {@link #allowUsbDebugging(boolean, String)} again. |
| */ |
| public void clearDebuggingKeys() { |
| mHandler.sendEmptyMessage(AdbDebuggingHandler.MESSAGE_ADB_CLEAR); |
| } |
| |
| /** |
| * Sends a message to the handler to persist the keystore. |
| */ |
| private void sendPersistKeyStoreMessage() { |
| Message msg = mHandler.obtainMessage(AdbDebuggingHandler.MESSAGE_ADB_PERSIST_KEYSTORE); |
| mHandler.sendMessage(msg); |
| } |
| |
| /** |
| * Dump the USB debugging state. |
| */ |
| public void dump(DualDumpOutputStream dump, String idName, long id) { |
| long token = dump.start(idName, id); |
| |
| dump.write("connected_to_adb", AdbDebuggingManagerProto.CONNECTED_TO_ADB, mThread != null); |
| writeStringIfNotNull(dump, "last_key_received", AdbDebuggingManagerProto.LAST_KEY_RECEVIED, |
| mFingerprints); |
| |
| try { |
| dump.write("user_keys", AdbDebuggingManagerProto.USER_KEYS, |
| FileUtils.readTextFile(new File("/data/misc/adb/adb_keys"), 0, null)); |
| } catch (IOException e) { |
| Slog.e(TAG, "Cannot read user keys", e); |
| } |
| |
| try { |
| dump.write("system_keys", AdbDebuggingManagerProto.SYSTEM_KEYS, |
| FileUtils.readTextFile(new File("/adb_keys"), 0, null)); |
| } catch (IOException e) { |
| Slog.e(TAG, "Cannot read system keys", e); |
| } |
| |
| try { |
| dump.write("keystore", AdbDebuggingManagerProto.KEYSTORE, |
| FileUtils.readTextFile(getAdbTempKeysFile(), 0, null)); |
| } catch (IOException e) { |
| Slog.e(TAG, "Cannot read keystore: ", e); |
| } |
| |
| dump.end(token); |
| } |
| |
| /** |
| * Handles adb keys for which the user has granted the 'always allow' option. This class ensures |
| * these grants are revoked after a period of inactivity as specified in the |
| * ADB_ALLOWED_CONNECTION_TIME setting. |
| */ |
| class AdbKeyStore { |
| private Map<String, Long> mKeyMap; |
| private Set<String> mSystemKeys; |
| private File mKeyFile; |
| private AtomicFile mAtomicKeyFile; |
| |
| private static final String XML_TAG_ADB_KEY = "adbKey"; |
| private static final String XML_ATTRIBUTE_KEY = "key"; |
| private static final String XML_ATTRIBUTE_LAST_CONNECTION = "lastConnection"; |
| private static final String SYSTEM_KEY_FILE = "/adb_keys"; |
| |
| /** |
| * Value returned by {@code getLastConnectionTime} when there is no previously saved |
| * connection time for the specified key. |
| */ |
| public static final long NO_PREVIOUS_CONNECTION = 0; |
| |
| /** |
| * Constructor that uses the default location for the persistent adb keystore. |
| */ |
| AdbKeyStore() { |
| init(); |
| } |
| |
| /** |
| * Constructor that uses the specified file as the location for the persistent adb keystore. |
| */ |
| AdbKeyStore(File keyFile) { |
| mKeyFile = keyFile; |
| init(); |
| } |
| |
| private void init() { |
| initKeyFile(); |
| mKeyMap = getKeyMap(); |
| mSystemKeys = getSystemKeysFromFile(SYSTEM_KEY_FILE); |
| addUserKeysToKeyStore(); |
| } |
| |
| /** |
| * Initializes the key file that will be used to persist the adb grants. |
| */ |
| private void initKeyFile() { |
| if (mKeyFile == null) { |
| mKeyFile = getAdbTempKeysFile(); |
| } |
| // getAdbTempKeysFile can return null if the adb file cannot be obtained |
| if (mKeyFile != null) { |
| mAtomicKeyFile = new AtomicFile(mKeyFile); |
| } |
| } |
| |
| private Set<String> getSystemKeysFromFile(String fileName) { |
| Set<String> systemKeys = new HashSet<>(); |
| File systemKeyFile = new File(fileName); |
| if (systemKeyFile.exists()) { |
| try (BufferedReader in = new BufferedReader(new FileReader(systemKeyFile))) { |
| String key; |
| while ((key = in.readLine()) != null) { |
| key = key.trim(); |
| if (key.length() > 0) { |
| systemKeys.add(key); |
| } |
| } |
| } catch (IOException e) { |
| Slog.e(TAG, "Caught an exception reading " + fileName + ": " + e); |
| } |
| } |
| return systemKeys; |
| } |
| |
| /** |
| * Returns whether there are any 'always allowed' keys in the keystore. |
| */ |
| public boolean isEmpty() { |
| return mKeyMap.isEmpty(); |
| } |
| |
| /** |
| * Iterates through the keys in the keystore and removes any that are beyond the window |
| * within which connections are automatically allowed without user interaction. |
| */ |
| public void updateKeyStore() { |
| if (filterOutOldKeys()) { |
| sendPersistKeyStoreMessage(); |
| } |
| } |
| |
| /** |
| * Returns the key map with the keys and last connection times from the key file. |
| */ |
| private Map<String, Long> getKeyMap() { |
| Map<String, Long> keyMap = new HashMap<String, Long>(); |
| // if the AtomicFile could not be instantiated before attempt again; if it still fails |
| // return an empty key map. |
| if (mAtomicKeyFile == null) { |
| initKeyFile(); |
| if (mAtomicKeyFile == null) { |
| Slog.e(TAG, "Unable to obtain the key file, " + mKeyFile + ", for reading"); |
| return keyMap; |
| } |
| } |
| if (!mAtomicKeyFile.exists()) { |
| return keyMap; |
| } |
| try (FileInputStream keyStream = mAtomicKeyFile.openRead()) { |
| XmlPullParser parser = Xml.newPullParser(); |
| parser.setInput(keyStream, StandardCharsets.UTF_8.name()); |
| XmlUtils.beginDocument(parser, XML_TAG_ADB_KEY); |
| while (parser.next() != XmlPullParser.END_DOCUMENT) { |
| String tagName = parser.getName(); |
| if (tagName == null) { |
| break; |
| } else if (!tagName.equals(XML_TAG_ADB_KEY)) { |
| XmlUtils.skipCurrentTag(parser); |
| continue; |
| } |
| String key = parser.getAttributeValue(null, XML_ATTRIBUTE_KEY); |
| long connectionTime; |
| try { |
| connectionTime = Long.valueOf( |
| parser.getAttributeValue(null, XML_ATTRIBUTE_LAST_CONNECTION)); |
| } catch (NumberFormatException e) { |
| Slog.e(TAG, |
| "Caught a NumberFormatException parsing the last connection time: " |
| + e); |
| XmlUtils.skipCurrentTag(parser); |
| continue; |
| } |
| keyMap.put(key, connectionTime); |
| } |
| } catch (IOException | XmlPullParserException e) { |
| Slog.e(TAG, "Caught an exception parsing the XML key file: ", e); |
| } |
| return keyMap; |
| } |
| |
| /** |
| * Updates the keystore with keys that were previously set to be always allowed before the |
| * connection time of keys was tracked. |
| */ |
| private void addUserKeysToKeyStore() { |
| File userKeyFile = getUserKeyFile(); |
| boolean mapUpdated = false; |
| if (userKeyFile != null && userKeyFile.exists()) { |
| try (BufferedReader in = new BufferedReader(new FileReader(userKeyFile))) { |
| long time = System.currentTimeMillis(); |
| String key; |
| while ((key = in.readLine()) != null) { |
| // if the keystore does not contain the key from the user key file then add |
| // it to the Map with the current system time to prevent it from expiring |
| // immediately if the user is actively using this key. |
| if (!mKeyMap.containsKey(key)) { |
| mKeyMap.put(key, time); |
| mapUpdated = true; |
| } |
| } |
| } catch (IOException e) { |
| Slog.e(TAG, "Caught an exception reading " + userKeyFile + ": " + e); |
| } |
| } |
| if (mapUpdated) { |
| sendPersistKeyStoreMessage(); |
| } |
| } |
| |
| /** |
| * Writes the key map to the key file. |
| */ |
| public void persistKeyStore() { |
| // if there is nothing in the key map then ensure any keys left in the keystore files |
| // are deleted as well. |
| filterOutOldKeys(); |
| if (mKeyMap.isEmpty()) { |
| deleteKeyStore(); |
| return; |
| } |
| if (mAtomicKeyFile == null) { |
| initKeyFile(); |
| if (mAtomicKeyFile == null) { |
| Slog.e(TAG, "Unable to obtain the key file, " + mKeyFile + ", for writing"); |
| return; |
| } |
| } |
| FileOutputStream keyStream = null; |
| try { |
| XmlSerializer serializer = new FastXmlSerializer(); |
| keyStream = mAtomicKeyFile.startWrite(); |
| serializer.setOutput(keyStream, StandardCharsets.UTF_8.name()); |
| serializer.startDocument(null, true); |
| |
| for (Map.Entry<String, Long> keyEntry : mKeyMap.entrySet()) { |
| serializer.startTag(null, XML_TAG_ADB_KEY); |
| serializer.attribute(null, XML_ATTRIBUTE_KEY, keyEntry.getKey()); |
| serializer.attribute(null, XML_ATTRIBUTE_LAST_CONNECTION, |
| String.valueOf(keyEntry.getValue())); |
| serializer.endTag(null, XML_TAG_ADB_KEY); |
| } |
| |
| serializer.endDocument(); |
| mAtomicKeyFile.finishWrite(keyStream); |
| } catch (IOException e) { |
| Slog.e(TAG, "Caught an exception writing the key map: ", e); |
| mAtomicKeyFile.failWrite(keyStream); |
| } |
| } |
| |
| private boolean filterOutOldKeys() { |
| boolean keysDeleted = false; |
| long allowedTime = getAllowedConnectionTime(); |
| long systemTime = System.currentTimeMillis(); |
| Iterator<Map.Entry<String, Long>> keyMapIterator = mKeyMap.entrySet().iterator(); |
| while (keyMapIterator.hasNext()) { |
| Map.Entry<String, Long> keyEntry = keyMapIterator.next(); |
| long connectionTime = keyEntry.getValue(); |
| if (allowedTime != 0 && systemTime > (connectionTime + allowedTime)) { |
| keyMapIterator.remove(); |
| keysDeleted = true; |
| } |
| } |
| // if any keys were deleted then the key file should be rewritten with the active keys |
| // to prevent authorizing a key that is now beyond the allowed window. |
| if (keysDeleted) { |
| writeKeys(mKeyMap.keySet()); |
| } |
| return keysDeleted; |
| } |
| |
| /** |
| * Returns the time in ms that the next key will expire or -1 if there are no keys or the |
| * keys will not expire. |
| */ |
| public long getNextExpirationTime() { |
| long minExpiration = -1; |
| long allowedTime = getAllowedConnectionTime(); |
| // if the allowedTime is 0 then keys never expire; return -1 to indicate this |
| if (allowedTime == 0) { |
| return minExpiration; |
| } |
| long systemTime = System.currentTimeMillis(); |
| Iterator<Map.Entry<String, Long>> keyMapIterator = mKeyMap.entrySet().iterator(); |
| while (keyMapIterator.hasNext()) { |
| Map.Entry<String, Long> keyEntry = keyMapIterator.next(); |
| long connectionTime = keyEntry.getValue(); |
| // if the key has already expired then ensure that the result is set to 0 so that |
| // any scheduled jobs to clean up the keystore can run right away. |
| long keyExpiration = Math.max(0, (connectionTime + allowedTime) - systemTime); |
| if (minExpiration == -1 || keyExpiration < minExpiration) { |
| minExpiration = keyExpiration; |
| } |
| } |
| return minExpiration; |
| } |
| |
| /** |
| * Removes all of the entries in the key map and deletes the key file. |
| */ |
| public void deleteKeyStore() { |
| mKeyMap.clear(); |
| deleteKeyFile(); |
| if (mAtomicKeyFile == null) { |
| return; |
| } |
| mAtomicKeyFile.delete(); |
| } |
| |
| /** |
| * Returns the time of the last connection from the specified key, or {@code |
| * NO_PREVIOUS_CONNECTION} if the specified key does not have an active adb grant. |
| */ |
| public long getLastConnectionTime(String key) { |
| return mKeyMap.getOrDefault(key, NO_PREVIOUS_CONNECTION); |
| } |
| |
| /** |
| * Sets the time of the last connection for the specified key to the provided time. |
| */ |
| public void setLastConnectionTime(String key, long connectionTime) { |
| setLastConnectionTime(key, connectionTime, false); |
| } |
| |
| /** |
| * Sets the time of the last connection for the specified key to the provided time. If force |
| * is set to true the time will be set even if it is older than the previously written |
| * connection time. |
| */ |
| public void setLastConnectionTime(String key, long connectionTime, boolean force) { |
| // Do not set the connection time to a value that is earlier than what was previously |
| // stored as the last connection time unless force is set. |
| if (mKeyMap.containsKey(key) && mKeyMap.get(key) >= connectionTime && !force) { |
| return; |
| } |
| // System keys are always allowed so there's no need to keep track of their connection |
| // time. |
| if (mSystemKeys.contains(key)) { |
| return; |
| } |
| // if this is the first time the key is being added then write it to the key file as |
| // well. |
| if (!mKeyMap.containsKey(key)) { |
| writeKey(key); |
| } |
| mKeyMap.put(key, connectionTime); |
| } |
| |
| /** |
| * Returns the connection time within which a connection from an allowed key is |
| * automatically allowed without user interaction. |
| */ |
| public long getAllowedConnectionTime() { |
| return Settings.Global.getLong(mContext.getContentResolver(), |
| Settings.Global.ADB_ALLOWED_CONNECTION_TIME, |
| Settings.Global.DEFAULT_ADB_ALLOWED_CONNECTION_TIME); |
| } |
| |
| /** |
| * Returns whether the specified key should be authroized to connect without user |
| * interaction. This requires that the user previously connected this device and selected |
| * the option to 'Always allow', and the time since the last connection is within the |
| * allowed window. |
| */ |
| public boolean isKeyAuthorized(String key) { |
| // A system key is always authorized to connect. |
| if (mSystemKeys.contains(key)) { |
| return true; |
| } |
| long lastConnectionTime = getLastConnectionTime(key); |
| if (lastConnectionTime == NO_PREVIOUS_CONNECTION) { |
| return false; |
| } |
| long allowedConnectionTime = getAllowedConnectionTime(); |
| // if the allowed connection time is 0 then revert to the previous behavior of always |
| // allowing previously granted adb grants. |
| if (allowedConnectionTime == 0 || (System.currentTimeMillis() < (lastConnectionTime |
| + allowedConnectionTime))) { |
| return true; |
| } else { |
| return false; |
| } |
| } |
| } |
| } |
