| /* |
| * Copyright (C) 2017 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.locksettings.recoverablekeystore; |
| |
| import static android.security.keystore.recovery.RecoveryController.ERROR_BAD_CERTIFICATE_FORMAT; |
| import static android.security.keystore.recovery.RecoveryController.ERROR_DECRYPTION_FAILED; |
| import static android.security.keystore.recovery.RecoveryController.ERROR_INSECURE_USER; |
| import static android.security.keystore.recovery.RecoveryController.ERROR_INVALID_KEY_FORMAT; |
| import static android.security.keystore.recovery.RecoveryController.ERROR_NO_SNAPSHOT_PENDING; |
| import static android.security.keystore.recovery.RecoveryController.ERROR_SERVICE_INTERNAL_ERROR; |
| import static android.security.keystore.recovery.RecoveryController.ERROR_SESSION_EXPIRED; |
| |
| import android.Manifest; |
| import android.annotation.NonNull; |
| import android.annotation.Nullable; |
| import android.app.PendingIntent; |
| import android.content.Context; |
| import android.os.Binder; |
| import android.os.RemoteException; |
| import android.os.ServiceSpecificException; |
| import android.os.UserHandle; |
| import android.security.keystore.recovery.KeyChainProtectionParams; |
| import android.security.keystore.recovery.KeyChainSnapshot; |
| import android.security.keystore.recovery.RecoveryCertPath; |
| import android.security.keystore.recovery.RecoveryController; |
| import android.security.keystore.recovery.WrappedApplicationKey; |
| import android.security.KeyStore; |
| import android.util.Log; |
| |
| import com.android.internal.annotations.VisibleForTesting; |
| import com.android.internal.util.HexDump; |
| import com.android.server.locksettings.recoverablekeystore.storage.ApplicationKeyStorage; |
| import com.android.server.locksettings.recoverablekeystore.certificate.CertParsingException; |
| import com.android.server.locksettings.recoverablekeystore.certificate.CertValidationException; |
| import com.android.server.locksettings.recoverablekeystore.certificate.CertXml; |
| import com.android.server.locksettings.recoverablekeystore.certificate.TrustedRootCert; |
| import com.android.server.locksettings.recoverablekeystore.storage.RecoverableKeyStoreDb; |
| import com.android.server.locksettings.recoverablekeystore.storage.RecoverySessionStorage; |
| import com.android.server.locksettings.recoverablekeystore.storage.RecoverySnapshotStorage; |
| |
| import java.security.InvalidKeyException; |
| import java.security.KeyFactory; |
| import java.security.KeyStoreException; |
| import java.security.NoSuchAlgorithmException; |
| import java.security.PublicKey; |
| import java.security.UnrecoverableKeyException; |
| import java.security.cert.CertPath; |
| import java.security.cert.CertificateEncodingException; |
| import java.security.cert.CertificateException; |
| import java.security.spec.InvalidKeySpecException; |
| import java.security.spec.X509EncodedKeySpec; |
| import java.util.Arrays; |
| import java.util.HashMap; |
| import java.util.List; |
| import java.util.Locale; |
| import java.util.Map; |
| import java.util.concurrent.ExecutorService; |
| import java.util.concurrent.Executors; |
| |
| import javax.crypto.AEADBadTagException; |
| |
| /** |
| * Class with {@link RecoveryController} API implementation and internal methods to interact |
| * with {@code LockSettingsService}. |
| * |
| * @hide |
| */ |
| public class RecoverableKeyStoreManager { |
| private static final String TAG = "RecoverableKeyStoreMgr"; |
| |
| private static RecoverableKeyStoreManager mInstance; |
| |
| private final Context mContext; |
| private final RecoverableKeyStoreDb mDatabase; |
| private final RecoverySessionStorage mRecoverySessionStorage; |
| private final ExecutorService mExecutorService; |
| private final RecoverySnapshotListenersStorage mListenersStorage; |
| private final RecoverableKeyGenerator mRecoverableKeyGenerator; |
| private final RecoverySnapshotStorage mSnapshotStorage; |
| private final PlatformKeyManager mPlatformKeyManager; |
| private final KeyStore mKeyStore; |
| private final ApplicationKeyStorage mApplicationKeyStorage; |
| |
| /** |
| * Returns a new or existing instance. |
| * |
| * @hide |
| */ |
| public static synchronized RecoverableKeyStoreManager |
| getInstance(Context context, KeyStore keystore) { |
| if (mInstance == null) { |
| RecoverableKeyStoreDb db = RecoverableKeyStoreDb.newInstance(context); |
| PlatformKeyManager platformKeyManager; |
| ApplicationKeyStorage applicationKeyStorage; |
| try { |
| platformKeyManager = PlatformKeyManager.getInstance(context, db); |
| applicationKeyStorage = ApplicationKeyStorage.getInstance(keystore); |
| } catch (NoSuchAlgorithmException e) { |
| // Impossible: all algorithms must be supported by AOSP |
| throw new RuntimeException(e); |
| } catch (KeyStoreException e) { |
| throw new ServiceSpecificException(ERROR_SERVICE_INTERNAL_ERROR, e.getMessage()); |
| } |
| |
| mInstance = new RecoverableKeyStoreManager( |
| context.getApplicationContext(), |
| keystore, |
| db, |
| new RecoverySessionStorage(), |
| Executors.newSingleThreadExecutor(), |
| new RecoverySnapshotStorage(), |
| new RecoverySnapshotListenersStorage(), |
| platformKeyManager, |
| applicationKeyStorage); |
| } |
| return mInstance; |
| } |
| |
| @VisibleForTesting |
| RecoverableKeyStoreManager( |
| Context context, |
| KeyStore keystore, |
| RecoverableKeyStoreDb recoverableKeyStoreDb, |
| RecoverySessionStorage recoverySessionStorage, |
| ExecutorService executorService, |
| RecoverySnapshotStorage snapshotStorage, |
| RecoverySnapshotListenersStorage listenersStorage, |
| PlatformKeyManager platformKeyManager, |
| ApplicationKeyStorage applicationKeyStorage) { |
| mContext = context; |
| mKeyStore = keystore; |
| mDatabase = recoverableKeyStoreDb; |
| mRecoverySessionStorage = recoverySessionStorage; |
| mExecutorService = executorService; |
| mListenersStorage = listenersStorage; |
| mSnapshotStorage = snapshotStorage; |
| mPlatformKeyManager = platformKeyManager; |
| mApplicationKeyStorage = applicationKeyStorage; |
| |
| try { |
| mRecoverableKeyGenerator = RecoverableKeyGenerator.newInstance(mDatabase); |
| } catch (NoSuchAlgorithmException e) { |
| Log.wtf(TAG, "AES keygen algorithm not available. AOSP must support this.", e); |
| throw new ServiceSpecificException(ERROR_SERVICE_INTERNAL_ERROR, e.getMessage()); |
| } |
| } |
| |
| public void initRecoveryService( |
| @NonNull String rootCertificateAlias, @NonNull byte[] recoveryServiceCertFile) |
| throws RemoteException { |
| checkRecoverKeyStorePermission(); |
| int userId = UserHandle.getCallingUserId(); |
| int uid = Binder.getCallingUid(); |
| |
| // TODO: Check the public-key signature on the whole file before parsing it |
| |
| CertXml certXml; |
| try { |
| certXml = CertXml.parse(recoveryServiceCertFile); |
| } catch (CertParsingException e) { |
| // TODO: Do not use raw key bytes anymore once the other components are updated |
| Log.d(TAG, "Failed to parse the input as a cert file: " + HexDump.toHexString( |
| recoveryServiceCertFile)); |
| PublicKey publicKey = parseEcPublicKey(recoveryServiceCertFile); |
| if (mDatabase.setRecoveryServicePublicKey(userId, uid, publicKey) > 0) { |
| mDatabase.setShouldCreateSnapshot(userId, uid, true); |
| } |
| Log.d(TAG, "Successfully set the input as the raw public key"); |
| return; |
| } |
| |
| // Check serial number |
| long newSerial = certXml.getSerial(); |
| Long oldSerial = mDatabase.getRecoveryServiceCertSerial(userId, uid); |
| if (oldSerial != null && oldSerial >= newSerial) { |
| if (oldSerial == newSerial) { |
| Log.i(TAG, "The cert file serial number is the same, so skip updating."); |
| } else { |
| Log.e(TAG, "The cert file serial number is older than the one in database."); |
| } |
| return; |
| } |
| Log.i(TAG, "Updating the certificate with the new serial number " + newSerial); |
| |
| CertPath certPath; |
| try { |
| Log.d(TAG, "Getting and validating a random endpoint certificate"); |
| certPath = certXml.getRandomEndpointCert(TrustedRootCert.TRUSTED_ROOT_CERT); |
| } catch (CertValidationException e) { |
| Log.e(TAG, "Invalid endpoint cert", e); |
| throw new ServiceSpecificException( |
| ERROR_BAD_CERTIFICATE_FORMAT, "Failed to validate certificate."); |
| } |
| try { |
| Log.d(TAG, "Saving the randomly chosen endpoint certificate to database"); |
| if (mDatabase.setRecoveryServiceCertPath(userId, uid, certPath) > 0) { |
| mDatabase.setRecoveryServiceCertSerial(userId, uid, newSerial); |
| mDatabase.setShouldCreateSnapshot(userId, uid, true); |
| } |
| } catch (CertificateEncodingException e) { |
| Log.e(TAG, "Failed to encode CertPath", e); |
| throw new ServiceSpecificException( |
| ERROR_BAD_CERTIFICATE_FORMAT, "Failed to encode CertPath."); |
| } |
| } |
| |
| private PublicKey parseEcPublicKey(@NonNull byte[] bytes) throws ServiceSpecificException { |
| try { |
| KeyFactory kf = KeyFactory.getInstance("EC"); |
| X509EncodedKeySpec pkSpec = new X509EncodedKeySpec(bytes); |
| return kf.generatePublic(pkSpec); |
| } catch (NoSuchAlgorithmException e) { |
| Log.wtf(TAG, "EC algorithm not available. AOSP must support this.", e); |
| throw new ServiceSpecificException(ERROR_SERVICE_INTERNAL_ERROR, e.getMessage()); |
| } catch (InvalidKeySpecException e) { |
| throw new ServiceSpecificException( |
| ERROR_BAD_CERTIFICATE_FORMAT, "Not a valid X509 certificate."); |
| } |
| } |
| |
| /** |
| * Gets all data necessary to recover application keys on new device. |
| * |
| * @return recovery data |
| * @hide |
| */ |
| public @NonNull |
| KeyChainSnapshot getKeyChainSnapshot() |
| throws RemoteException { |
| checkRecoverKeyStorePermission(); |
| int uid = Binder.getCallingUid(); |
| KeyChainSnapshot snapshot = mSnapshotStorage.get(uid); |
| if (snapshot == null) { |
| throw new ServiceSpecificException(ERROR_NO_SNAPSHOT_PENDING); |
| } |
| return snapshot; |
| } |
| |
| public void setSnapshotCreatedPendingIntent(@Nullable PendingIntent intent) |
| throws RemoteException { |
| checkRecoverKeyStorePermission(); |
| int uid = Binder.getCallingUid(); |
| mListenersStorage.setSnapshotListener(uid, intent); |
| } |
| |
| /** |
| * Gets recovery snapshot versions for all accounts. Note that snapshot may have 0 application |
| * keys, but it still needs to be synced, if previous versions were not empty. |
| * |
| * @return Map from Recovery agent account to snapshot version. |
| */ |
| public @NonNull Map<byte[], Integer> getRecoverySnapshotVersions() |
| throws RemoteException { |
| checkRecoverKeyStorePermission(); |
| throw new UnsupportedOperationException(); |
| } |
| |
| public void setServerParams(byte[] serverParams) throws RemoteException { |
| checkRecoverKeyStorePermission(); |
| int userId = UserHandle.getCallingUserId(); |
| int uid = Binder.getCallingUid(); |
| long updatedRows = mDatabase.setServerParams(userId, uid, serverParams); |
| if (updatedRows > 0) { |
| mDatabase.setShouldCreateSnapshot(userId, uid, true); |
| } |
| } |
| |
| /** |
| * Sets the recovery status of key with {@code alias} to {@code status}. |
| */ |
| public void setRecoveryStatus(String alias, int status) throws RemoteException { |
| checkRecoverKeyStorePermission(); |
| mDatabase.setRecoveryStatus(Binder.getCallingUid(), alias, status); |
| } |
| |
| /** |
| * Returns recovery statuses for all keys belonging to the calling uid. |
| * |
| * @return {@link Map} from key alias to recovery status. Recovery status is one of |
| * {@link RecoveryController#RECOVERY_STATUS_SYNCED}, |
| * {@link RecoveryController#RECOVERY_STATUS_SYNC_IN_PROGRESS} or |
| * {@link RecoveryController#RECOVERY_STATUS_PERMANENT_FAILURE}. |
| */ |
| public @NonNull Map<String, Integer> getRecoveryStatus() throws RemoteException { |
| return mDatabase.getStatusForAllKeys(Binder.getCallingUid()); |
| } |
| |
| /** |
| * Sets recovery secrets list used by all recovery agents for given {@code userId} |
| * |
| * @hide |
| */ |
| public void setRecoverySecretTypes( |
| @NonNull @KeyChainProtectionParams.UserSecretType int[] secretTypes) |
| throws RemoteException { |
| checkRecoverKeyStorePermission(); |
| int userId = UserHandle.getCallingUserId(); |
| int uid = Binder.getCallingUid(); |
| long updatedRows = mDatabase.setRecoverySecretTypes(userId, uid, secretTypes); |
| if (updatedRows > 0) { |
| mDatabase.setShouldCreateSnapshot(userId, uid, true); |
| } |
| } |
| |
| /** |
| * Gets secret types necessary to create Recovery Data. |
| * |
| * @return secret types |
| * @hide |
| */ |
| public @NonNull int[] getRecoverySecretTypes() throws RemoteException { |
| checkRecoverKeyStorePermission(); |
| return mDatabase.getRecoverySecretTypes(UserHandle.getCallingUserId(), |
| Binder.getCallingUid()); |
| } |
| |
| /** |
| * Gets secret types RecoveryManagers is waiting for to create new Recovery Data. |
| * |
| * @return secret types |
| * @hide |
| */ |
| public @NonNull int[] getPendingRecoverySecretTypes() throws RemoteException { |
| checkRecoverKeyStorePermission(); |
| throw new UnsupportedOperationException(); |
| } |
| |
| public void recoverySecretAvailable( |
| @NonNull KeyChainProtectionParams recoverySecret) throws RemoteException { |
| int uid = Binder.getCallingUid(); |
| if (recoverySecret.getLockScreenUiFormat() == KeyChainProtectionParams.TYPE_LOCKSCREEN) { |
| throw new SecurityException( |
| "Caller " + uid + " is not allowed to set lock screen secret"); |
| } |
| checkRecoverKeyStorePermission(); |
| // TODO: add hook from LockSettingsService to set lock screen secret. |
| throw new UnsupportedOperationException(); |
| } |
| |
| /** |
| * Initializes recovery session given the X509-encoded public key of the recovery service. |
| * |
| * @param sessionId A unique ID to identify the recovery session. |
| * @param verifierPublicKey X509-encoded public key. |
| * @param vaultParams Additional params associated with vault. |
| * @param vaultChallenge Challenge issued by vault service. |
| * @param secrets Lock-screen hashes. For now only a single secret is supported. |
| * @return Encrypted bytes of recovery claim. This can then be issued to the vault service. |
| * @deprecated Use {@link #startRecoverySessionWithCertPath(String, RecoveryCertPath, byte[], |
| * byte[], List)} instead. |
| * |
| * @hide |
| */ |
| public @NonNull byte[] startRecoverySession( |
| @NonNull String sessionId, |
| @NonNull byte[] verifierPublicKey, |
| @NonNull byte[] vaultParams, |
| @NonNull byte[] vaultChallenge, |
| @NonNull List<KeyChainProtectionParams> secrets) |
| throws RemoteException { |
| checkRecoverKeyStorePermission(); |
| int uid = Binder.getCallingUid(); |
| |
| if (secrets.size() != 1) { |
| throw new UnsupportedOperationException( |
| "Only a single KeyChainProtectionParams is supported"); |
| } |
| |
| PublicKey publicKey; |
| try { |
| publicKey = KeySyncUtils.deserializePublicKey(verifierPublicKey); |
| } catch (InvalidKeySpecException e) { |
| throw new ServiceSpecificException(ERROR_BAD_CERTIFICATE_FORMAT, |
| "Not a valid X509 key"); |
| } |
| // The raw public key bytes contained in vaultParams must match the ones given in |
| // verifierPublicKey; otherwise, the user secret may be decrypted by a key that is not owned |
| // by the original recovery service. |
| if (!publicKeysMatch(publicKey, vaultParams)) { |
| throw new ServiceSpecificException(ERROR_BAD_CERTIFICATE_FORMAT, |
| "The public keys given in verifierPublicKey and vaultParams do not match."); |
| } |
| |
| byte[] keyClaimant = KeySyncUtils.generateKeyClaimant(); |
| byte[] kfHash = secrets.get(0).getSecret(); |
| mRecoverySessionStorage.add( |
| uid, |
| new RecoverySessionStorage.Entry(sessionId, kfHash, keyClaimant, vaultParams)); |
| |
| try { |
| byte[] thmKfHash = KeySyncUtils.calculateThmKfHash(kfHash); |
| return KeySyncUtils.encryptRecoveryClaim( |
| publicKey, |
| vaultParams, |
| vaultChallenge, |
| thmKfHash, |
| keyClaimant); |
| } catch (NoSuchAlgorithmException e) { |
| Log.wtf(TAG, "SecureBox algorithm missing. AOSP must support this.", e); |
| throw new ServiceSpecificException(ERROR_SERVICE_INTERNAL_ERROR, e.getMessage()); |
| } catch (InvalidKeyException e) { |
| throw new ServiceSpecificException(ERROR_BAD_CERTIFICATE_FORMAT, e.getMessage()); |
| } |
| } |
| |
| /** |
| * Initializes recovery session given the certificate path of the recovery service. |
| * |
| * @param sessionId A unique ID to identify the recovery session. |
| * @param verifierCertPath The certificate path of the recovery service. |
| * @param vaultParams Additional params associated with vault. |
| * @param vaultChallenge Challenge issued by vault service. |
| * @param secrets Lock-screen hashes. For now only a single secret is supported. |
| * @return Encrypted bytes of recovery claim. This can then be issued to the vault service. |
| * |
| * @hide |
| */ |
| public @NonNull byte[] startRecoverySessionWithCertPath( |
| @NonNull String sessionId, |
| @NonNull RecoveryCertPath verifierCertPath, |
| @NonNull byte[] vaultParams, |
| @NonNull byte[] vaultChallenge, |
| @NonNull List<KeyChainProtectionParams> secrets) |
| throws RemoteException { |
| checkRecoverKeyStorePermission(); |
| |
| CertPath certPath; |
| try { |
| certPath = verifierCertPath.getCertPath(); |
| } catch (CertificateException e) { |
| throw new ServiceSpecificException(ERROR_BAD_CERTIFICATE_FORMAT, |
| "Failed decode the certificate path"); |
| } |
| |
| // TODO: Validate the cert path according to the root of trust |
| |
| if (certPath.getCertificates().isEmpty()) { |
| throw new ServiceSpecificException(ERROR_BAD_CERTIFICATE_FORMAT, |
| "The given CertPath is empty"); |
| } |
| byte[] verifierPublicKey = certPath.getCertificates().get(0).getPublicKey().getEncoded(); |
| if (verifierPublicKey == null) { |
| Log.e(TAG, "Failed to encode verifierPublicKey"); |
| throw new ServiceSpecificException(ERROR_BAD_CERTIFICATE_FORMAT, |
| "Failed to encode verifierPublicKey"); |
| } |
| |
| return startRecoverySession( |
| sessionId, verifierPublicKey, vaultParams, vaultChallenge, secrets); |
| } |
| |
| /** |
| * Invoked by a recovery agent after a successful recovery claim is sent to the remote vault |
| * service. |
| * |
| * @param sessionId The session ID used to generate the claim. See |
| * {@link #startRecoverySession(String, byte[], byte[], byte[], List)}. |
| * @param encryptedRecoveryKey The encrypted recovery key blob returned by the remote vault |
| * service. |
| * @param applicationKeys The encrypted key blobs returned by the remote vault service. These |
| * were wrapped with the recovery key. |
| * @return Map from alias to raw key material. |
| * @throws RemoteException if an error occurred recovering the keys. |
| */ |
| public Map<String, byte[]> recoverKeys( |
| @NonNull String sessionId, |
| @NonNull byte[] encryptedRecoveryKey, |
| @NonNull List<WrappedApplicationKey> applicationKeys) |
| throws RemoteException { |
| checkRecoverKeyStorePermission(); |
| int uid = Binder.getCallingUid(); |
| RecoverySessionStorage.Entry sessionEntry = mRecoverySessionStorage.get(uid, sessionId); |
| if (sessionEntry == null) { |
| throw new ServiceSpecificException(ERROR_SESSION_EXPIRED, |
| String.format(Locale.US, |
| "Application uid=%d does not have pending session '%s'", uid, sessionId)); |
| } |
| |
| try { |
| byte[] recoveryKey = decryptRecoveryKey(sessionEntry, encryptedRecoveryKey); |
| return recoverApplicationKeys(recoveryKey, applicationKeys); |
| } finally { |
| sessionEntry.destroy(); |
| mRecoverySessionStorage.remove(uid); |
| } |
| } |
| |
| /** |
| * Deprecated |
| * Generates a key named {@code alias} in the recoverable store for the calling uid. Then |
| * returns the raw key material. |
| * |
| * <p>TODO: Once AndroidKeyStore has added move api, do not return raw bytes. |
| * |
| * @deprecated |
| * @hide |
| */ |
| public byte[] generateAndStoreKey(@NonNull String alias) throws RemoteException { |
| int uid = Binder.getCallingUid(); |
| int userId = UserHandle.getCallingUserId(); |
| |
| PlatformEncryptionKey encryptionKey; |
| try { |
| encryptionKey = mPlatformKeyManager.getEncryptKey(userId); |
| } catch (NoSuchAlgorithmException e) { |
| // Impossible: all algorithms must be supported by AOSP |
| throw new RuntimeException(e); |
| } catch (KeyStoreException | UnrecoverableKeyException e) { |
| throw new ServiceSpecificException(ERROR_SERVICE_INTERNAL_ERROR, e.getMessage()); |
| } catch (InsecureUserException e) { |
| throw new ServiceSpecificException(ERROR_INSECURE_USER, e.getMessage()); |
| } |
| |
| try { |
| return mRecoverableKeyGenerator.generateAndStoreKey(encryptionKey, userId, uid, alias); |
| } catch (KeyStoreException | InvalidKeyException | RecoverableKeyStorageException e) { |
| throw new ServiceSpecificException(ERROR_SERVICE_INTERNAL_ERROR, e.getMessage()); |
| } |
| } |
| |
| /** |
| * Destroys the session with the given {@code sessionId}. |
| */ |
| public void closeSession(@NonNull String sessionId) throws RemoteException { |
| mRecoverySessionStorage.remove(Binder.getCallingUid(), sessionId); |
| } |
| |
| public void removeKey(@NonNull String alias) throws RemoteException { |
| int uid = Binder.getCallingUid(); |
| int userId = UserHandle.getCallingUserId(); |
| |
| boolean wasRemoved = mDatabase.removeKey(uid, alias); |
| if (wasRemoved) { |
| mDatabase.setShouldCreateSnapshot(userId, uid, true); |
| mApplicationKeyStorage.deleteEntry(userId, uid, alias); |
| } |
| } |
| |
| /** |
| * Generates a key named {@code alias} in caller's namespace. |
| * The key is stored in system service keystore namespace. |
| * |
| * @return grant alias, which caller can use to access the key. |
| */ |
| public String generateKey(@NonNull String alias) throws RemoteException { |
| int uid = Binder.getCallingUid(); |
| int userId = UserHandle.getCallingUserId(); |
| |
| PlatformEncryptionKey encryptionKey; |
| try { |
| encryptionKey = mPlatformKeyManager.getEncryptKey(userId); |
| } catch (NoSuchAlgorithmException e) { |
| // Impossible: all algorithms must be supported by AOSP |
| throw new RuntimeException(e); |
| } catch (KeyStoreException | UnrecoverableKeyException e) { |
| throw new ServiceSpecificException(ERROR_SERVICE_INTERNAL_ERROR, e.getMessage()); |
| } catch (InsecureUserException e) { |
| throw new ServiceSpecificException(ERROR_INSECURE_USER, e.getMessage()); |
| } |
| |
| try { |
| byte[] secretKey = |
| mRecoverableKeyGenerator.generateAndStoreKey(encryptionKey, userId, uid, alias); |
| mApplicationKeyStorage.setSymmetricKeyEntry(userId, uid, alias, secretKey); |
| return mApplicationKeyStorage.getGrantAlias(userId, uid, alias); |
| } catch (KeyStoreException | InvalidKeyException | RecoverableKeyStorageException e) { |
| throw new ServiceSpecificException(ERROR_SERVICE_INTERNAL_ERROR, e.getMessage()); |
| } |
| } |
| |
| /** |
| * Imports a 256-bit AES-GCM key named {@code alias}. The key is stored in system service |
| * keystore namespace. |
| * |
| * @param alias the alias provided by caller as a reference to the key. |
| * @param keyBytes the raw bytes of the 256-bit AES key. |
| * @return grant alias, which caller can use to access the key. |
| * @throws RemoteException if the given key is invalid or some internal errors occur. |
| * |
| * @hide |
| */ |
| public String importKey(@NonNull String alias, @NonNull byte[] keyBytes) |
| throws RemoteException { |
| if (keyBytes == null || |
| keyBytes.length != RecoverableKeyGenerator.KEY_SIZE_BITS / Byte.SIZE) { |
| Log.e(TAG, "The given key for import doesn't have the required length " |
| + RecoverableKeyGenerator.KEY_SIZE_BITS); |
| throw new ServiceSpecificException(ERROR_INVALID_KEY_FORMAT, |
| "The given key does not contain " + RecoverableKeyGenerator.KEY_SIZE_BITS |
| + " bits."); |
| } |
| |
| int uid = Binder.getCallingUid(); |
| int userId = UserHandle.getCallingUserId(); |
| |
| // TODO: Refactor RecoverableKeyGenerator to wrap the PlatformKey logic |
| |
| PlatformEncryptionKey encryptionKey; |
| try { |
| encryptionKey = mPlatformKeyManager.getEncryptKey(userId); |
| } catch (NoSuchAlgorithmException e) { |
| // Impossible: all algorithms must be supported by AOSP |
| throw new RuntimeException(e); |
| } catch (KeyStoreException | UnrecoverableKeyException e) { |
| throw new ServiceSpecificException(ERROR_SERVICE_INTERNAL_ERROR, e.getMessage()); |
| } catch (InsecureUserException e) { |
| throw new ServiceSpecificException(ERROR_INSECURE_USER, e.getMessage()); |
| } |
| |
| try { |
| // Wrap the key by the platform key and store the wrapped key locally |
| mRecoverableKeyGenerator.importKey(encryptionKey, userId, uid, alias, keyBytes); |
| |
| // Import the key to Android KeyStore and get grant |
| mApplicationKeyStorage.setSymmetricKeyEntry(userId, uid, alias, keyBytes); |
| return mApplicationKeyStorage.getGrantAlias(userId, uid, alias); |
| } catch (KeyStoreException | InvalidKeyException | RecoverableKeyStorageException e) { |
| throw new ServiceSpecificException(ERROR_SERVICE_INTERNAL_ERROR, e.getMessage()); |
| } |
| } |
| |
| /** |
| * Gets a key named {@code alias} in caller's namespace. |
| * |
| * @return grant alias, which caller can use to access the key. |
| */ |
| public String getKey(@NonNull String alias) throws RemoteException { |
| int uid = Binder.getCallingUid(); |
| int userId = UserHandle.getCallingUserId(); |
| String grantAlias = mApplicationKeyStorage.getGrantAlias(userId, uid, alias); |
| return grantAlias; |
| } |
| |
| private byte[] decryptRecoveryKey( |
| RecoverySessionStorage.Entry sessionEntry, byte[] encryptedClaimResponse) |
| throws RemoteException, ServiceSpecificException { |
| byte[] locallyEncryptedKey; |
| try { |
| locallyEncryptedKey = KeySyncUtils.decryptRecoveryClaimResponse( |
| sessionEntry.getKeyClaimant(), |
| sessionEntry.getVaultParams(), |
| encryptedClaimResponse); |
| } catch (InvalidKeyException e) { |
| Log.e(TAG, "Got InvalidKeyException during decrypting recovery claim response", e); |
| throw new ServiceSpecificException(ERROR_DECRYPTION_FAILED, |
| "Failed to decrypt recovery key " + e.getMessage()); |
| } catch (AEADBadTagException e) { |
| Log.e(TAG, "Got AEADBadTagException during decrypting recovery claim response", e); |
| throw new ServiceSpecificException(ERROR_DECRYPTION_FAILED, |
| "Failed to decrypt recovery key " + e.getMessage()); |
| } catch (NoSuchAlgorithmException e) { |
| // Should never happen: all the algorithms used are required by AOSP implementations |
| throw new ServiceSpecificException(ERROR_SERVICE_INTERNAL_ERROR, e.getMessage()); |
| } |
| |
| try { |
| return KeySyncUtils.decryptRecoveryKey(sessionEntry.getLskfHash(), locallyEncryptedKey); |
| } catch (InvalidKeyException e) { |
| Log.e(TAG, "Got InvalidKeyException during decrypting recovery key", e); |
| throw new ServiceSpecificException(ERROR_DECRYPTION_FAILED, |
| "Failed to decrypt recovery key " + e.getMessage()); |
| } catch (AEADBadTagException e) { |
| Log.e(TAG, "Got AEADBadTagException during decrypting recovery key", e); |
| throw new ServiceSpecificException(ERROR_DECRYPTION_FAILED, |
| "Failed to decrypt recovery key " + e.getMessage()); |
| } catch (NoSuchAlgorithmException e) { |
| // Should never happen: all the algorithms used are required by AOSP implementations |
| throw new ServiceSpecificException(ERROR_SERVICE_INTERNAL_ERROR, e.getMessage()); |
| } |
| } |
| |
| /** |
| * Uses {@code recoveryKey} to decrypt {@code applicationKeys}. |
| * |
| * @return Map from alias to raw key material. |
| * @throws RemoteException if an error occurred decrypting the keys. |
| */ |
| private Map<String, byte[]> recoverApplicationKeys( |
| @NonNull byte[] recoveryKey, |
| @NonNull List<WrappedApplicationKey> applicationKeys) throws RemoteException { |
| HashMap<String, byte[]> keyMaterialByAlias = new HashMap<>(); |
| for (WrappedApplicationKey applicationKey : applicationKeys) { |
| String alias = applicationKey.getAlias(); |
| byte[] encryptedKeyMaterial = applicationKey.getEncryptedKeyMaterial(); |
| |
| try { |
| byte[] keyMaterial = |
| KeySyncUtils.decryptApplicationKey(recoveryKey, encryptedKeyMaterial); |
| keyMaterialByAlias.put(alias, keyMaterial); |
| } catch (NoSuchAlgorithmException e) { |
| Log.wtf(TAG, "Missing SecureBox algorithm. AOSP required to support this.", e); |
| throw new ServiceSpecificException( |
| ERROR_SERVICE_INTERNAL_ERROR, e.getMessage()); |
| } catch (InvalidKeyException e) { |
| Log.e(TAG, "Got InvalidKeyException during decrypting application key with alias: " |
| + alias, e); |
| throw new ServiceSpecificException(ERROR_DECRYPTION_FAILED, |
| "Failed to recover key with alias '" + alias + "': " + e.getMessage()); |
| } catch (AEADBadTagException e) { |
| Log.e(TAG, "Got AEADBadTagException during decrypting application key with alias: " |
| + alias, e); |
| // Ignore the exception to continue to recover the other application keys. |
| } |
| } |
| if (!applicationKeys.isEmpty() && keyMaterialByAlias.isEmpty()) { |
| Log.e(TAG, "Failed to recover any of the application keys."); |
| throw new ServiceSpecificException(ERROR_DECRYPTION_FAILED, |
| "Failed to recover any of the application keys."); |
| } |
| return keyMaterialByAlias; |
| } |
| |
| /** |
| * This function can only be used inside LockSettingsService. |
| * |
| * @param storedHashType from {@code CredentialHash} |
| * @param credential - unencrypted String. Password length should be at most 16 symbols {@code |
| * mPasswordMaxLength} |
| * @param userId for user who just unlocked the device. |
| * @hide |
| */ |
| public void lockScreenSecretAvailable( |
| int storedHashType, @NonNull String credential, int userId) { |
| // So as not to block the critical path unlocking the phone, defer to another thread. |
| try { |
| mExecutorService.execute(KeySyncTask.newInstance( |
| mContext, |
| mDatabase, |
| mSnapshotStorage, |
| mListenersStorage, |
| userId, |
| storedHashType, |
| credential, |
| /*credentialUpdated=*/ false)); |
| } catch (NoSuchAlgorithmException e) { |
| Log.wtf(TAG, "Should never happen - algorithm unavailable for KeySync", e); |
| } catch (KeyStoreException e) { |
| Log.e(TAG, "Key store error encountered during recoverable key sync", e); |
| } catch (InsecureUserException e) { |
| Log.wtf(TAG, "Impossible - insecure user, but user just entered lock screen", e); |
| } |
| } |
| |
| /** |
| * This function can only be used inside LockSettingsService. |
| * |
| * @param storedHashType from {@code CredentialHash} |
| * @param credential - unencrypted String |
| * @param userId for the user whose lock screen credentials were changed. |
| * @hide |
| */ |
| public void lockScreenSecretChanged( |
| int storedHashType, |
| @Nullable String credential, |
| int userId) { |
| // So as not to block the critical path unlocking the phone, defer to another thread. |
| try { |
| mExecutorService.execute(KeySyncTask.newInstance( |
| mContext, |
| mDatabase, |
| mSnapshotStorage, |
| mListenersStorage, |
| userId, |
| storedHashType, |
| credential, |
| /*credentialUpdated=*/ true)); |
| } catch (NoSuchAlgorithmException e) { |
| Log.wtf(TAG, "Should never happen - algorithm unavailable for KeySync", e); |
| } catch (KeyStoreException e) { |
| Log.e(TAG, "Key store error encountered during recoverable key sync", e); |
| } catch (InsecureUserException e) { |
| Log.e(TAG, "InsecureUserException during lock screen secret update", e); |
| } |
| } |
| |
| private void checkRecoverKeyStorePermission() { |
| mContext.enforceCallingOrSelfPermission( |
| Manifest.permission.RECOVER_KEYSTORE, |
| "Caller " + Binder.getCallingUid() + " doesn't have RecoverKeyStore permission."); |
| } |
| |
| private boolean publicKeysMatch(PublicKey publicKey, byte[] vaultParams) { |
| byte[] encodedPublicKey = SecureBox.encodePublicKey(publicKey); |
| return Arrays.equals(encodedPublicKey, Arrays.copyOf(vaultParams, encodedPublicKey.length)); |
| } |
| } |