Allow weaker unlock methods in Android 6 - 10 (fixes #4833)

app/src/main/java/eu/kanade/tachiyomi/ui/security/BiometricUnlockActivity.kt

@@ -6,6 +6,7 @@ import androidx.biometric.BiometricPrompt
 import eu.kanade.tachiyomi.R
 import eu.kanade.tachiyomi.data.preference.PreferencesHelper
 import eu.kanade.tachiyomi.util.system.BiometricUtil
+import timber.log.Timber
 import uy.kohesive.injekt.injectLazy
 import java.util.Date
 import java.util.concurrent.Executors
@@ -27,6 +28,7 @@ class BiometricUnlockActivity : AppCompatActivity() {
             object : BiometricPrompt.AuthenticationCallback() {
                 override fun onAuthenticationError(errorCode: Int, errString: CharSequence) {
                     super.onAuthenticationError(errorCode, errString)
+                    Timber.e(errString.toString())
                     finishAffinity()
                 }
 

app/src/main/java/eu/kanade/tachiyomi/util/system/BiometricUtil.kt

@@ -1,12 +1,17 @@
 package eu.kanade.tachiyomi.util.system
 
 import android.content.Context
+import android.os.Build
 import androidx.biometric.BiometricManager
 import androidx.biometric.BiometricManager.Authenticators
 
 object BiometricUtil {
 
     fun getSupportedAuthenticators(context: Context): Int {
+        if (isLegacySecured(context)) {
+            return Authenticators.BIOMETRIC_WEAK or Authenticators.DEVICE_CREDENTIAL
+        }
+
         return listOf(
             Authenticators.BIOMETRIC_STRONG,
             Authenticators.BIOMETRIC_WEAK,
@@ -17,10 +22,22 @@ object BiometricUtil {
     }
 
     fun isSupported(context: Context): Boolean {
-        return getSupportedAuthenticators(context) != 0
+        return isLegacySecured(context) || getSupportedAuthenticators(context) != 0
     }
 
     fun isDeviceCredentialAllowed(context: Context): Boolean {
-        return getSupportedAuthenticators(context) and Authenticators.DEVICE_CREDENTIAL != 0
+        return isLegacySecured(context) || (getSupportedAuthenticators(context) and Authenticators.DEVICE_CREDENTIAL != 0)
+    }
+
+    /**
+     * Returns whether the device is secured with a PIN, pattern or password.
+     */
+    private fun isLegacySecured(context: Context): Boolean {
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M && Build.VERSION.SDK_INT <= Build.VERSION_CODES.Q) {
+            if (context.keyguardManager.isDeviceSecure) {
+                return true
+            }
+        }
+        return false
     }
 }

app/src/main/java/eu/kanade/tachiyomi/util/system/ContextExtensions.kt

@@ -1,6 +1,7 @@
 package eu.kanade.tachiyomi.util.system
 
 import android.app.ActivityManager
+import android.app.KeyguardManager
 import android.app.Notification
 import android.app.NotificationManager
 import android.content.BroadcastReceiver
@@ -153,24 +154,18 @@ val Float.dpToPxEnd: Float
 val Resources.isLTR
     get() = configuration.layoutDirection == View.LAYOUT_DIRECTION_LTR
 
-/**
- * Property to get the notification manager from the context.
- */
 val Context.notificationManager: NotificationManager
     get() = getSystemService()!!
 
-/**
- * Property to get the connectivity manager from the context.
- */
 val Context.connectivityManager: ConnectivityManager
     get() = getSystemService()!!
 
-/**
- * Property to get the power manager from the context.
- */
 val Context.powerManager: PowerManager
     get() = getSystemService()!!
 
+val Context.keyguardManager: KeyguardManager
+    get() = getSystemService()!!
+
 /**
  * Convenience method to acquire a partial wake lock.
  */