Better biometric key implementation

app/src/main/java/com/kunzisoft/keepass/biometric/AdvancedUnlockedViewManager.kt

@@ -25,9 +25,9 @@ class AdvancedUnlockedViewManager(var context: FragmentActivity,
                                   var onCheckedPasswordChangeListener: CompoundButton.OnCheckedChangeListener? = null,
                                   var passwordView: TextView?,
                                   var loadDatabase: (password: String?) -> Unit)
-    : BiometricHelper.BiometricUnlockCallback {
+    : BiometricUnlockDatabaseHelper.BiometricUnlockCallback {
 
-    private var biometricHelper: BiometricHelper? = null
+    private var biometricUnlockDatabaseHelper: BiometricUnlockDatabaseHelper? = null
     private var biometricMode: Mode = Mode.NOT_CONFIGURED
 
     private var isBiometricPromptAutoOpenEnable = PreferencesUtil.isBiometricPromptAutoOpenEnable(context)
@@ -46,11 +46,11 @@ class AdvancedUnlockedViewManager(var context: FragmentActivity,
 
         // Check if fingerprint well init (be called the first time the fingerprint is configured
         // and the activity still active)
-        if (biometricHelper == null || !biometricHelper!!.isFingerprintInitialized) {
+        if (biometricUnlockDatabaseHelper == null || !biometricUnlockDatabaseHelper!!.isFingerprintInitialized) {
 
-            biometricHelper = BiometricHelper(context, this)
+            biometricUnlockDatabaseHelper = BiometricUnlockDatabaseHelper(context, this)
             // callback for fingerprint findings
-            biometricHelper?.setAuthenticationCallback(biometricCallback)
+            biometricUnlockDatabaseHelper?.setAuthenticationCallback(biometricCallback)
         }
 
         // Add a check listener to change fingerprint mode
@@ -131,12 +131,12 @@ class AdvancedUnlockedViewManager(var context: FragmentActivity,
                 Mode.WAIT_CREDENTIAL -> {}
                 Mode.STORE -> {
                     // newly store the entered password in encrypted way
-                    biometricHelper?.encryptData(passwordView?.text.toString())
+                    biometricUnlockDatabaseHelper?.encryptData(passwordView?.text.toString())
                 }
                 Mode.OPEN -> {
                     // retrieve the encrypted value from preferences
                     prefsNoBackup.getString(preferenceKeyValue, null)?.let {
-                        biometricHelper?.decryptData(it)
+                        biometricUnlockDatabaseHelper?.decryptData(it)
                     }
                 }
             }
@@ -174,7 +174,7 @@ class AdvancedUnlockedViewManager(var context: FragmentActivity,
         setAdvancedUnlockedTitleView(R.string.open_biometric_prompt_store_credential)
         setAdvancedUnlockedMessageView("")
 
-        biometricHelper?.initEncryptData { biometricPrompt, cryptoObject, promptInfo ->
+        biometricUnlockDatabaseHelper?.initEncryptData { biometricPrompt, cryptoObject, promptInfo ->
 
             cryptoObject?.let { crypto ->
                 // Set listener to open the biometric dialog and save credential
@@ -193,9 +193,9 @@ class AdvancedUnlockedViewManager(var context: FragmentActivity,
         setAdvancedUnlockedTitleView(R.string.open_biometric_prompt_unlock_database)
         setAdvancedUnlockedMessageView("")
 
-        if (biometricHelper != null) {
+        if (biometricUnlockDatabaseHelper != null) {
             prefsNoBackup.getString(preferenceKeyIvSpec, null)?.let {
-                biometricHelper?.initDecryptData(it) { biometricPrompt, cryptoObject, promptInfo ->
+                biometricUnlockDatabaseHelper?.initDecryptData(it) { biometricPrompt, cryptoObject, promptInfo ->
 
                     cryptoObject?.let { crypto ->
                         // Set listener to open the biometric dialog and check credential
@@ -244,7 +244,7 @@ class AdvancedUnlockedViewManager(var context: FragmentActivity,
 
         biometricMode = Mode.UNAVAILABLE
         initBiometricMode()
-        biometricHelper = null
+        biometricUnlockDatabaseHelper = null
     }
 
     fun inflateOptionsMenu(menuInflater: MenuInflater, menu: Menu) {
@@ -262,7 +262,7 @@ class AdvancedUnlockedViewManager(var context: FragmentActivity,
     }
 
     fun deleteEntryKey() {
-        biometricHelper?.deleteEntryKey()
+        biometricUnlockDatabaseHelper?.deleteEntryKey()
         removePrefsNoBackupKey()
         biometricMode = Mode.NOT_CONFIGURED
         checkBiometricAvailability()

app/src/main/java/com/kunzisoft/keepass/biometric/BiometricUnlockDatabaseHelper.kt

@@ -46,7 +46,7 @@ import javax.crypto.SecretKey
 import javax.crypto.spec.IvParameterSpec
 
 @RequiresApi(api = Build.VERSION_CODES.M)
-class BiometricHelper(private val context: FragmentActivity, private val biometricUnlockCallback: BiometricUnlockCallback?) {
+class BiometricUnlockDatabaseHelper(private val context: FragmentActivity, private val biometricUnlockCallback: BiometricUnlockCallback?) {
 
     private var biometricPrompt: BiometricPrompt? = null
 
@@ -130,7 +130,7 @@ class BiometricHelper(private val context: FragmentActivity, private val biometr
                                         .build())
                         keyGenerator?.generateKey()
                     }
-                }catch (e: Exception) {
+                } catch (e: Exception) {
                     Log.e(TAG, "Unable to create a key in keystore", e)
                     biometricUnlockCallback?.onBiometricException(e)
                 }
@@ -289,7 +289,7 @@ class BiometricHelper(private val context: FragmentActivity, private val biometr
 
     companion object {
 
-        private val TAG = BiometricHelper::class.java.name
+        private val TAG = BiometricUnlockDatabaseHelper::class.java.name
 
         private const val BIOMETRIC_KEYSTORE = "AndroidKeyStore"
         private const val BIOMETRIC_KEYSTORE_KEY = "com.kunzisoft.keepass.biometric.key"
@@ -302,7 +302,7 @@ class BiometricHelper(private val context: FragmentActivity, private val biometr
          */
         fun deleteEntryKeyInKeystoreForBiometric(context: FragmentActivity,
                                                  biometricUnlockCallback: BiometricUnlockErrorCallback) {
-            val fingerPrintHelper = BiometricHelper(context, object : BiometricUnlockCallback {
+            val fingerPrintHelper = BiometricUnlockDatabaseHelper(context, object : BiometricUnlockCallback {
 
                 override fun handleEncryptedResult(value: String, ivSpec: String) {}
 

app/src/main/java/com/kunzisoft/keepass/settings/NestedSettingsFragment.kt

@@ -48,7 +48,7 @@ import com.kunzisoft.keepass.activities.stylish.Stylish
 import com.kunzisoft.keepass.app.database.FileDatabaseHistory
 import com.kunzisoft.keepass.database.element.Database
 import com.kunzisoft.keepass.education.Education
-import com.kunzisoft.keepass.biometric.BiometricHelper
+import com.kunzisoft.keepass.biometric.BiometricUnlockDatabaseHelper
 import com.kunzisoft.keepass.biometric.AdvancedUnlockedViewManager
 import com.kunzisoft.keepass.icons.IconPackChooser
 import com.kunzisoft.keepass.settings.preferencedialogfragment.*
@@ -252,9 +252,9 @@ class NestedSettingsFragment : PreferenceFragmentCompat(), Preference.OnPreferen
                                 .setPositiveButton(resources.getString(android.R.string.yes)
                                 ) { _, _ ->
                                     if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
-                                        BiometricHelper.deleteEntryKeyInKeystoreForBiometric(
+                                        BiometricUnlockDatabaseHelper.deleteEntryKeyInKeystoreForBiometric(
                                                 activity,
-                                                object : BiometricHelper.BiometricUnlockErrorCallback {
+                                                object : BiometricUnlockDatabaseHelper.BiometricUnlockErrorCallback {
                                                     override fun onInvalidKeyException(e: Exception) {}
 
                                                     override fun onBiometricException(e: Exception) {

app/src/main/java/com/kunzisoft/keepass/view/AdvancedUnlockInfoView.kt

@@ -72,12 +72,16 @@ class AdvancedUnlockInfoView @JvmOverloads constructor(context: Context,
         title = context.getString(textId)
     }
 
-    var message: CharSequence
+    var message: CharSequence?
         get() {
             return unlockMessageTextView?.text?.toString() ?: ""
         }
         set(value) {
-            unlockMessageTextView?.text = value
+            if (value == null || value.isEmpty())
+                unlockMessageTextView?.visibility = GONE
+            else
+                unlockMessageTextView?.visibility = VISIBLE
+            unlockMessageTextView?.text = value ?: ""
         }
 
     fun setMessage(@StringRes textId: Int) {

app/src/main/res/layout-v23/fragment_fingerprint_explanation.xml

@@ -103,6 +103,7 @@
                 android:layout_width="48dp"
                 android:layout_height="48dp"
                 android:elevation="4dp"
+                android:layout_marginBottom="12dp"
                 android:src="@drawable/fingerprint"
                 android:background="@drawable/background_image"
                 tools:targetApi="lollipop" />
@@ -112,7 +113,6 @@
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:orientation="horizontal"
-            android:layout_marginTop="12dp"
             android:layout_marginBottom="8dp">
             <TextView
                 android:layout_width="20dp"