Move AdbKeyStore to its own file outside of AdbDebuggingManager (0e2c64f8) · Commits · e / os / android_frameworks_base

services/core/java/com/android/server/adb/AdbDebuggingManager.java

+71 −319

Original line number	Diff line number	Diff line
		@@ -84,33 +84,16 @@ import java.util.AbstractMap;
		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;
		import java.util.concurrent.CopyOnWriteArraySet;
		import java.util.concurrent.TimeoutException;

		/**
		* Provides communication to the Android Debug Bridge daemon to allow, deny, or clear public keys
		* that are authorized to connect to the ADB service itself.
		*
		* <p>The AdbDebuggingManager controls two files:
		*
		* <ol>
		* <li>adb_keys
		* <li>adb_temp_keys.xml
		* </ol>
		*
		* <p>The ADB Daemon (adbd) reads <em>only</em> the adb_keys file for authorization. Public keys
		* from registered hosts are stored in adb_keys, one entry per line.
		*
		* <p>AdbDebuggingManager also keeps adb_temp_keys.xml, which is used for two things
		*
		* <ol>
		* <li>Removing unused keys from the adb_keys file
		* <li>Managing authorized WiFi access points for ADB over WiFi
		* </ol>
		* Manages communication with the Android Debug Bridge (ADB) daemon to allow, deny, or clear public
		* keys that are authorized to connect to the ADB service itself. The storage of authorized public
		* keys is done through {@link AdbKeyStore}.
		*/
		public class AdbDebuggingManager {
		private static final String TAG = AdbDebuggingManager.class.getSimpleName();
		@@ -144,8 +127,19 @@ public class AdbDebuggingManager {
		private static final long ADBD_STATE_CHANGE_TIMEOUT = DEFAULT_DISPATCHING_TIMEOUT_MILLIS;

		private AdbPairingThread mAdbPairingThread = null;
		// A list of keys connected via wifi
		private final Set<String> mWifiConnectedKeys = new HashSet<>();

		/**
		* The set of public keys for devices currently connected over Wi-Fi ADB.
		*
		* <p>This collection is thread-safe for reads from any thread but MUST only be modified on the
		* {@link AdbDebuggingHandler} thread to avoid dead locks.
		*
		* <p>{@link CopyOnWriteArraySet} is used because reads (for updating the UI) are expected to be
		* much more frequent than writes (device connections and disconnections), making lock-free
		* reads highly efficient.
		*/
		private final Set<String> mWifiConnectedKeys = new CopyOnWriteArraySet<>();

		// The current info of the adbwifi connection.
		private final AdbConnectionInfo mAdbConnectionInfo = new AdbConnectionInfo();

		@@ -610,7 +604,13 @@ public class AdbDebuggingManager {
		@VisibleForTesting
		void initKeyStore() {
		if (mAdbKeyStore == null) {
		mAdbKeyStore = new AdbKeyStore();
		mAdbKeyStore =
		new AdbKeyStore(
		mContext,
		mTempKeysFile,
		mUserKeyFile,
		mTicker,
		() -> sendPersistKeyStoreMessage());
		}
		}

		@@ -899,13 +899,13 @@ public class AdbDebuggingManager {
		mThread.sendResponse(cmdStr);
		mAdbKeyStore.removeKey(publicKey);
		// Send the updated paired devices list to the UI.
		sendPairedDevicesToUI(mAdbKeyStore.getPairedDevices());
		sendPairedDevicesToUI(getPairedDevicesForKeys(mAdbKeyStore.getKeys()));
		}
		case MSG_RESPONSE_PAIRING_RESULT -> {
		String publicKey = (String) msg.obj;
		onPairingResult(publicKey);
		// Send the updated paired devices list to the UI.
		sendPairedDevicesToUI(mAdbKeyStore.getPairedDevices());
		sendPairedDevicesToUI(getPairedDevicesForKeys(mAdbKeyStore.getKeys()));
		}
		case MSG_RESPONSE_PAIRING_PORT -> {
		int port = (int) msg.obj;
		@@ -939,14 +939,14 @@ public class AdbDebuggingManager {
		case MSG_WIFI_DEVICE_CONNECTED -> {
		String key = (String) msg.obj;
		if (mWifiConnectedKeys.add(key)) {
		sendPairedDevicesToUI(mAdbKeyStore.getPairedDevices());
		sendPairedDevicesToUI(getPairedDevicesForKeys(mAdbKeyStore.getKeys()));
		showAdbConnectedNotification(true);
		}
		}
		case MSG_WIFI_DEVICE_DISCONNECTED -> {
		String key = (String) msg.obj;
		if (mWifiConnectedKeys.remove(key)) {
		sendPairedDevicesToUI(mAdbKeyStore.getPairedDevices());
		sendPairedDevicesToUI(getPairedDevicesForKeys(mAdbKeyStore.getKeys()));
		if (mWifiConnectedKeys.isEmpty()) {
		showAdbConnectedNotification(false);
		}
		@@ -1082,7 +1082,7 @@ public class AdbDebuggingManager {

		private void onAdbdWifiServerConnected(int port) {
		// Send the paired devices list to the UI
		sendPairedDevicesToUI(mAdbKeyStore.getPairedDevices());
		sendPairedDevicesToUI(getPairedDevicesForKeys(mAdbKeyStore.getKeys()));
		sendServerConnectionState(true, port);
		}

		@@ -1198,7 +1198,22 @@ public class AdbDebuggingManager {
		}
		}

		private String getFingerprints(String key) {
		/**
		* Calculates and returns the MD5 fingerprint of a given key string. The key string is expected
		* to be a Base64 encoded string, optionally followed by whitespace and other content. Only the
		* first part (before any whitespace) is used for the fingerprint calculation.
		*
		* <p>The MD5 fingerprint is returned as a colon-separated hexadecimal string. For example:
		* "A1:B2:C3:D4:E5:F6:A7:B8:C9:D0:E1:F2:A3:B4:C5:D6"
		*
		* @param key The key string from which to generate the fingerprint. Expected to contain a
		* Base64 encoded string as its first part.
		* @return The MD5 fingerprint of the decoded Base64 key, or an empty string if the input key is
		* null, if the MD5 algorithm is not available, or if there's an error during Base64
		* decoding.
		*/
		// TODO(b/420613813) move to AdbKey object.
		static String getFingerprints(String key) {
		String hex = "0123456789ABCDEF";
		StringBuilder sb = new StringBuilder();
		MessageDigest digester;
		@@ -1434,8 +1449,32 @@ public class AdbDebuggingManager {

		/** Returns the list of paired devices. */
		public Map<String, PairDevice> getPairedDevices() {
		AdbKeyStore keystore = new AdbKeyStore();
		return keystore.getPairedDevices();
		AdbKeyStore keystore =
		new AdbKeyStore(
		mContext,
		mTempKeysFile,
		mUserKeyFile,
		mTicker,
		() -> sendPersistKeyStoreMessage());
		return getPairedDevicesForKeys(keystore.getKeys());
		}

		private Map<String, PairDevice> getPairedDevicesForKeys(Set<String> keys) {
		Map<String, PairDevice> pairedDevices = new HashMap();
		for (String key : keys) {
		String fingerprints = getFingerprints(key);
		String hostname = "nouser@nohostname";
		String[] args = key.split("\\s+");
		if (args.length > 1) {
		hostname = args[1];
		}
		PairDevice pairDevice = new PairDevice();
		pairDevice.name = hostname;
		pairDevice.guid = fingerprints;
		pairDevice.connected = mWifiConnectedKeys.contains(key);
		pairedDevices.put(key, pairDevice);
		}
		return pairedDevices;
		}

		/** Unpair with device */
		@@ -1528,293 +1567,6 @@ public class AdbDebuggingManager {
		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 final Set<String> mSystemKeys;
		private AdbAuthorizationStore.Entries mAuthEntries;

		/**
		* Manages the list of keys that adbd always allows to connect, regardless of last
		* connection-time.
		*
		* <p>This list of keys along with #{mSystemKeys} represents the source of truth for adbd.
		*/
		private final AdbdKeyStoreStorage mAdbKeyUser;

		/**
		* Manages the list of temporary keys, including their last connection time, and the list of
		* trusted networks.
		*/
		private final AdbAuthorizationStore mAuthStore;

		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;

		/**
		* Create an AdbKeyStore instance.
		*
		* <p>Upon creation, we parse {@link #mTempKeysFile} to determine authorized WiFi APs and
		* retrieve the map of stored ADB keys and their last connected times. After that, we read
		* the {@link #mUserKeyFile}, and any keys that exist in that file that do not exist in the
		* map are added to the map (for backwards compatibility).
		*/
		AdbKeyStore() {
		mAdbKeyUser = new AdbdKeyStoreStorage(mUserKeyFile);
		mAuthStore = new AdbAuthorizationStore(mTempKeysFile);
		mAuthEntries = mAuthStore.load();

		// The system keystore handles keys pre-loaded into the read-only system partition at
		// /adb_keys. Unlike the user keystore (/data/misc/adb/adb_keys), these
		// system keys are considered permanently trusted, are not subject to expiration, and
		// cannot be modified by the user.
		AdbdKeyStoreStorage systemKeyStore = new AdbdKeyStoreStorage(
		new File(SYSTEM_KEY_FILE));
		mSystemKeys = systemKeyStore.loadKeys();
		copyUserKeysToTempAuthorizationStore();
		}

		public void reloadKeyMap() {
		mAuthEntries = mAuthStore.load();
		}

		public void addTrustedNetwork(String bssid) {
		mAuthEntries.trustedNetworks().add(bssid);
		sendPersistKeyStoreMessage();
		}

		public Map<String, PairDevice> getPairedDevices() {
		Map<String, PairDevice> pairedDevices = new HashMap<String, PairDevice>();
		for (Map.Entry<String, Long> keyEntry : mAuthEntries.keys().entrySet()) {
		String fingerprints = getFingerprints(keyEntry.getKey());
		String hostname = "nouser@nohostname";
		String[] args = keyEntry.getKey().split("\\s+");
		if (args.length > 1) {
		hostname = args[1];
		}
		PairDevice pairDevice = new PairDevice();
		pairDevice.name = hostname;
		pairDevice.guid = fingerprints;
		pairDevice.connected = mWifiConnectedKeys.contains(keyEntry.getKey());
		pairedDevices.put(keyEntry.getKey(), pairDevice);
		}
		return pairedDevices;
		}

		public String findKeyFromFingerprint(String fingerprint) {
		for (Map.Entry<String, Long> entry : mAuthEntries.keys().entrySet()) {
		String f = getFingerprints(entry.getKey());
		if (fingerprint.equals(f)) {
		return entry.getKey();
		}
		}
		return null;
		}

		public void removeKey(String key) {
		if (mAuthEntries.keys().containsKey(key)) {
		mAuthEntries.keys().remove(key);
		sendPersistKeyStoreMessage();
		}
		}

		/**
		* Returns whether there are any 'always allowed' keys in the keystore.
		*/
		public boolean isEmpty() {
		return mAuthEntries.keys().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();
		}
		}

		/**
		* Copies keys from the user key file to the temp authorization store. This ensures that
		* keys that were previously authorized before the introduction of the keystore are still
		* authorized.
		*/
		private void copyUserKeysToTempAuthorizationStore() {
		Set<String> keys = mAdbKeyUser.loadKeys();
		boolean mapUpdated = false;
		for (String key : keys) {
		if (!mAuthEntries.keys().containsKey(key)) {
		// 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.
		mAuthEntries.keys().put(key, mTicker.currentTimeMillis());
		mapUpdated = true;
		}
		}
		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 (mAuthEntries.isEmpty()) {
		deleteKeyStore();
		return;
		}
		mAuthStore.save(mAuthEntries);
		mAdbKeyUser.saveKeys(mAuthEntries.keys().keySet());
		}

		private boolean filterOutOldKeys() {
		long allowedTime = getAllowedConnectionTime();
		if (allowedTime == 0) {
		return false;
		}
		boolean keysDeleted = false;
		long systemTime = mTicker.currentTimeMillis();
		Iterator<Map.Entry<String, Long>> keyMapIterator =
		mAuthEntries.keys().entrySet().iterator();
		while (keyMapIterator.hasNext()) {
		Map.Entry<String, Long> keyEntry = keyMapIterator.next();
		long connectionTime = keyEntry.getValue();
		if (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) {
		mAdbKeyUser.saveKeys(mAuthEntries.keys().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 = mTicker.currentTimeMillis();
		Iterator<Map.Entry<String, Long>> keyMapIterator =
		mAuthEntries.keys().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() {
		mAuthEntries.clear();
		mAuthStore.delete();
		mAdbKeyUser.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 mAuthEntries.keys().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.
		*/
		@VisibleForTesting
		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 (mAuthEntries.keys().containsKey(key)
		&& mAuthEntries.keys().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;
		}
		mAuthEntries.keys().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.
		return allowedConnectionTime == 0
		\|\| (mTicker.currentTimeMillis() < (lastConnectionTime + allowedConnectionTime));
		}

		/**
		* Returns whether the specified bssid is in the list of trusted networks. This requires
		* that the user previously allowed wireless debugging on this network and selected the
		* option to 'Always allow'.
		*/
		public boolean isTrustedNetwork(String bssid) {
		return mAuthEntries.trustedNetworks().contains(bssid);
		}
		}

		/**
		* A Guava-like interface for getting the current system time.
		*

services/core/java/com/android/server/adb/AdbKeyStore.java

0 → 100644

+337 −0

File added.

Preview size limit exceeded, changes collapsed.

services/tests/servicestests/src/com/android/server/adb/AdbDebuggingManagerTest.java

+40 −6

Original line number	Diff line number	Diff line
		@@ -36,6 +36,8 @@ import android.util.Log;

		import androidx.test.InstrumentationRegistry;

		import com.android.server.adb.AdbDebuggingManager.AdbDebuggingHandler;

		import org.junit.After;
		import org.junit.Before;
		import org.junit.Test;
		@@ -86,7 +88,7 @@ public final class AdbDebuggingManagerTest {
		private AdbDebuggingManager mManager;
		private AdbDebuggingManager.AdbDebuggingThread mThread;
		private AdbDebuggingManager.AdbDebuggingHandler mHandler;
		private AdbDebuggingManager.AdbKeyStore mKeyStore;
		private AdbKeyStore mKeyStore;
		private BlockingQueue<TestResult> mBlockingQueue;
		private long mOriginalAllowedConnectionTime;
		private File mAdbKeyXmlFile;
		@@ -277,9 +279,16 @@ public final class AdbDebuggingManagerTest {
		// Send a message to the handler to persist the updated keystore and verify a new key store
		// backed by the XML file contains the key.
		persistKeyStore();
		AdbKeyStore newKeyStore = new AdbKeyStore(
		mContext,
		mAdbKeyXmlFile,
		mAdbKeyFile,
		mFakeTicker,
		() -> mHandler.obtainMessage(AdbDebuggingHandler.MESSAGE_ADB_PERSIST_KEYSTORE)
		.sendToTarget());
		assertTrue(
		"The key with the 'Always allow' option selected was not persisted in the keystore",
		mManager.new AdbKeyStore().isKeyAuthorized(TEST_KEY_1));
		newKeyStore.isKeyAuthorized(TEST_KEY_1));

		// Get the current last connection time to ensure it is updated in the persisted keystore.
		long lastConnectionTime = mKeyStore.getLastConnectionTime(TEST_KEY_1);
		@@ -293,10 +302,17 @@ public final class AdbDebuggingManagerTest {
		// Persist the updated last connection time and verify a new key store backed by the XML
		// file contains the updated connection time.
		persistKeyStore();
		newKeyStore = new AdbKeyStore(
		mContext,
		mAdbKeyXmlFile,
		mAdbKeyFile,
		mFakeTicker,
		() -> mHandler.obtainMessage(AdbDebuggingHandler.MESSAGE_ADB_PERSIST_KEYSTORE)
		.sendToTarget());
		assertNotEquals(
		"The last connection time in the key file was not updated after the update "
		+ "connection time message", lastConnectionTime,
		mManager.new AdbKeyStore().getLastConnectionTime(TEST_KEY_1));
		newKeyStore.getLastConnectionTime(TEST_KEY_1));
		// Verify that the key is in the adb_keys file
		assertTrue("The key was not in the adb_keys file after persisting the keystore",
		isKeyInFile(TEST_KEY_1, mAdbKeyFile));
		@@ -641,7 +657,13 @@ public final class AdbDebuggingManagerTest {
		setAllowedConnectionTime(Settings.Global.DEFAULT_ADB_ALLOWED_CONNECTION_TIME);

		// The untracked keys should be added to the keystore as part of the constructor.
		AdbDebuggingManager.AdbKeyStore adbKeyStore = mManager.new AdbKeyStore();
		AdbKeyStore adbKeyStore = new AdbKeyStore(
		mContext,
		mAdbKeyXmlFile,
		mAdbKeyFile,
		mFakeTicker,
		() -> mHandler.obtainMessage(AdbDebuggingHandler.MESSAGE_ADB_PERSIST_KEYSTORE)
		.sendToTarget());

		// Verify that the connection time for each test key is within a small value of the current
		// time.
		@@ -762,7 +784,13 @@ public final class AdbDebuggingManagerTest {
		persistKeyStore();

		mFakeTicker.advance(10);
		AdbDebuggingManager.AdbKeyStore newKeyStore = mManager.new AdbKeyStore();
		AdbKeyStore newKeyStore = new AdbKeyStore(
		mContext,
		mAdbKeyXmlFile,
		mAdbKeyFile,
		mFakeTicker,
		() -> mHandler.obtainMessage(AdbDebuggingHandler.MESSAGE_ADB_PERSIST_KEYSTORE)
		.sendToTarget());

		assertEquals(
		"KeyStore not populated from the XML file.",
		@@ -825,7 +853,13 @@ public final class AdbDebuggingManagerTest {
		mKeyStore.addTrustedNetwork(trustedNetwork);
		persistKeyStore();

		AdbDebuggingManager.AdbKeyStore newKeyStore = mManager.new AdbKeyStore();
		AdbKeyStore newKeyStore = new AdbKeyStore(
		mContext,
		mAdbKeyXmlFile,
		mAdbKeyFile,
		mFakeTicker,
		() -> mHandler.obtainMessage(AdbDebuggingHandler.MESSAGE_ADB_PERSIST_KEYSTORE)
		.sendToTarget());

		assertTrue(
		"Persisted trusted network not found in new keystore instance.",