Automatically dismiss decryption screen after 60 seconds

CHANGELOG.md

@@ -13,6 +13,7 @@ All notable changes to this project will be documented in this file.
 -   Cancelling the Autofill "Generate password" action now correctly returns you to the original app.
 -   If multiple username fields exist in the password, we now ensure the later ones are not dropped from extra content.
 -   Icons in Autofill suggestions are no longer black on almost black in dark mode.
+-   Decrypt screen would stay in memory infinitely, allowing passwords to be seen without re-auth
 
 ### Changed
 

app/src/main/java/com/zeapo/pwdstore/crypto/DecryptActivity.kt

@@ -113,6 +113,18 @@ class DecryptActivity : BasePgpActivity(), OpenPgpServiceConnection.OnBound {
         e(e)
     }
 
+    /**
+     * Automatically finishes the activity 60 seconds after decryption succeeded to prevent
+     * information leaks from stale activities.
+     */
+    @OptIn(ExperimentalTime::class)
+    private fun startAutoDismissTimer() {
+        lifecycleScope.launch {
+            delay(60.seconds)
+            finish()
+        }
+    }
+
     /**
      * Edit the current password and hide all the fields populated by encrypted data so that when
      * the result triggers they can be repopulated with new data.
@@ -155,6 +167,7 @@ class DecryptActivity : BasePgpActivity(), OpenPgpServiceConnection.OnBound {
             api?.executeApiAsync(data, inputStream, outputStream) { result ->
                 when (result?.getIntExtra(OpenPgpApi.RESULT_CODE, OpenPgpApi.RESULT_CODE_ERROR)) {
                     OpenPgpApi.RESULT_CODE_SUCCESS -> {
+                        startAutoDismissTimer()
                         runCatching {
                             val showPassword = settings.getBoolean(PreferenceKeys.SHOW_PASSWORD, true)
                             val showExtraContent = settings.getBoolean(PreferenceKeys.SHOW_EXTRA_CONTENT, true)