add checkbox in passphrase dialog to clear cache (#3127)

* add checkbox in passphrase dialog to clear cache

* instantiating PasswordDialog via newInstance, passing args as Bundle

* refactor: put checkbox directly in the layout

---------

Co-authored-by: Harsh Shandilya <me@msfjarvis.dev>

app/src/main/java/app/passwordstore/ui/autofill/AutofillDecryptActivity.kt

@@ -11,6 +11,7 @@ import android.content.IntentSender
 import android.os.Build
 import android.os.Bundle
 import android.view.autofill.AutofillManager
+import androidx.core.content.edit
 import androidx.fragment.app.setFragmentResultListener
 import androidx.lifecycle.lifecycleScope
 import app.passwordstore.Application.Companion.screenWasOff
@@ -53,6 +54,7 @@ class AutofillDecryptActivity : BasePGPActivity() {
   @Inject lateinit var passphraseCache: PGPPassphraseCache
 
   private lateinit var directoryStructure: DirectoryStructure
+  private var clearCache = true
 
   override fun onStart() {
     super.onStart()
@@ -114,7 +116,8 @@ class AutofillDecryptActivity : BasePGPActivity() {
         is Result.Success -> {
           /* clear passphrase cache on first use after application startup or if screen was off;
           also make sure to purge a stale cache after caching has been disabled via PGP settings */
-          if (screenWasOff && settings.getBoolean(PreferenceKeys.CLEAR_PASSPHRASE_CACHE, true)) {
+          clearCache = settings.getBoolean(PreferenceKeys.CLEAR_PASSPHRASE_CACHE, true)
+          if (screenWasOff && clearCache) {
             passphraseCache.clearAllCachedPassphrases(this@AutofillDecryptActivity)
             screenWasOff = false
           }
@@ -149,11 +152,16 @@ class AutofillDecryptActivity : BasePGPActivity() {
       decryptWithPassphrase(File(filePath), identifiers, clientState, action, password = "")
       return
     }
-    val dialog = PasswordDialog()
+    val dialog =
+      PasswordDialog.newInstance(
+        cacheEnabled = features.isEnabled(EnablePGPPassphraseCache),
+        clearCache = clearCache,
+      )
     dialog.show(supportFragmentManager, "PASSWORD_DIALOG")
     dialog.setFragmentResultListener(PasswordDialog.PASSWORD_RESULT_KEY) { key, bundle ->
       if (key == PasswordDialog.PASSWORD_RESULT_KEY) {
-        val value = bundle.getString(PasswordDialog.PASSWORD_RESULT_KEY)!!
+        val value = bundle.getString(PasswordDialog.PASSWORD_PHRASE_KEY)!!
+        clearCache = bundle.getBoolean(PasswordDialog.PASSWORD_CLEAR_KEY)
         lifecycleScope.launch(dispatcherProvider.main()) {
           decryptWithPassphrase(File(filePath), identifiers, clientState, action, value)
         }
@@ -185,6 +193,8 @@ class AutofillDecryptActivity : BasePGPActivity() {
           Intent().apply { putExtra(AutofillManager.EXTRA_AUTHENTICATION_RESULT, fillInDataset) },
         )
       }
+      if (features.isEnabled(EnablePGPPassphraseCache))
+        settings.edit { putBoolean(PreferenceKeys.CLEAR_PASSPHRASE_CACHE, clearCache) }
     }
     withContext(dispatcherProvider.main()) { finish() }
   }

app/src/main/java/app/passwordstore/ui/crypto/DecryptActivity.kt

@@ -9,6 +9,7 @@ import android.content.Intent
 import android.os.Bundle
 import android.view.Menu
 import android.view.MenuItem
+import androidx.core.content.edit
 import androidx.fragment.app.setFragmentResultListener
 import androidx.lifecycle.lifecycleScope
 import app.passwordstore.Application.Companion.screenWasOff
@@ -56,6 +57,7 @@ class DecryptActivity : BasePGPActivity() {
   private val relativeParentPath by unsafeLazy { getParentPath(fullPath, repoPath) }
   private var passwordEntry: PasswordEntry? = null
   private var retries = 0
+  private var clearCache = true
 
   override fun onCreate(savedInstanceState: Bundle?) {
     super.onCreate(savedInstanceState)
@@ -170,7 +172,8 @@ class DecryptActivity : BasePGPActivity() {
         is BiometricResult.Success -> {
           /* clear passphrase cache on first use after application startup or if screen was off;
           also make sure to purge a stale cache after caching has been disabled via PGP settings */
-          if (screenWasOff && settings.getBoolean(PreferenceKeys.CLEAR_PASSPHRASE_CACHE, true)) {
+          clearCache = settings.getBoolean(PreferenceKeys.CLEAR_PASSPHRASE_CACHE, true)
+          if (screenWasOff && clearCache) {
             passphraseCache.clearAllCachedPassphrases(this@DecryptActivity)
             screenWasOff = false
           }
@@ -200,14 +203,19 @@ class DecryptActivity : BasePGPActivity() {
       decryptWithPassphrase(passphrase = "", gpgIdentifiers, authResult)
       return
     }
-    val dialog = PasswordDialog()
+    val dialog =
+      PasswordDialog.newInstance(
+        cacheEnabled = features.isEnabled(EnablePGPPassphraseCache),
+        clearCache = clearCache,
+      )
     if (isError) {
       dialog.setError()
     }
     dialog.show(supportFragmentManager, "PASSWORD_DIALOG")
     dialog.setFragmentResultListener(PasswordDialog.PASSWORD_RESULT_KEY) { key, bundle ->
       if (key == PasswordDialog.PASSWORD_RESULT_KEY) {
-        val passphrase = bundle.getString(PasswordDialog.PASSWORD_RESULT_KEY)!!
+        val passphrase = bundle.getString(PasswordDialog.PASSWORD_PHRASE_KEY)!!
+        clearCache = bundle.getBoolean(PasswordDialog.PASSWORD_CLEAR_KEY)
         lifecycleScope.launch(dispatcherProvider.main()) {
           decryptWithPassphrase(passphrase, gpgIdentifiers, authResult) {
             if (authResult is BiometricResult.Success) {
@@ -231,6 +239,8 @@ class DecryptActivity : BasePGPActivity() {
   ) {
     val result = decryptPGPStream(passphrase, identifiers)
     if (result.isOk) {
+      if (features.isEnabled(EnablePGPPassphraseCache))
+        settings.edit { putBoolean(PreferenceKeys.CLEAR_PASSPHRASE_CACHE, clearCache) }
       val entry = passwordEntryFactory.create(result.value.toByteArray())
       passwordEntry = entry
       createPasswordUI(entry)

app/src/main/java/app/passwordstore/ui/crypto/PasswordDialog.kt

@@ -25,11 +25,21 @@ class PasswordDialog : DialogFragment() {
 
   private val binding by unsafeLazy { DialogPasswordEntryBinding.inflate(layoutInflater) }
   private var isError: Boolean = false
+  private var clearCacheChecked: Boolean = true
 
   override fun onCreateDialog(savedInstanceState: Bundle?): Dialog {
     val builder = MaterialAlertDialogBuilder(requireContext())
     builder.setView(binding.root)
     builder.setTitle(R.string.password)
+
+    if (requireArguments().getBoolean(CACHE_ENABLED_EXTRA, false)) {
+      clearCacheChecked = requireArguments().getBoolean(AUTO_CLEAR_CACHE_EXTRA)
+      binding.autoClearCache.isChecked = clearCacheChecked
+      binding.autoClearCache.setOnCheckedChangeListener { _, isChecked ->
+        clearCacheChecked = isChecked
+      }
+    }
+
     builder.setPositiveButton(android.R.string.ok) { _, _ -> setPasswordAndDismiss() }
     val dialog = builder.create()
     dialog.window?.setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_VISIBLE)
@@ -64,11 +74,28 @@ class PasswordDialog : DialogFragment() {
 
   private fun setPasswordAndDismiss() {
     val password = binding.passwordEditText.text.toString()
-    setFragmentResult(PASSWORD_RESULT_KEY, bundleOf(PASSWORD_RESULT_KEY to password))
+    setFragmentResult(
+      PASSWORD_RESULT_KEY,
+      bundleOf(PASSWORD_PHRASE_KEY to password, PASSWORD_CLEAR_KEY to clearCacheChecked),
+    )
     dismissAllowingStateLoss()
   }
 
   companion object {
+
+    private const val CACHE_ENABLED_EXTRA = "CACHE_ENABLED"
+    private const val AUTO_CLEAR_CACHE_EXTRA = "AUTO_CLEAR_CACHE"
+
     const val PASSWORD_RESULT_KEY = "password_result"
+    const val PASSWORD_PHRASE_KEY = "password_phrase"
+    const val PASSWORD_CLEAR_KEY = "password_clear"
+
+    fun newInstance(cacheEnabled: Boolean, clearCache: Boolean): PasswordDialog {
+      val extras =
+        bundleOf(CACHE_ENABLED_EXTRA to cacheEnabled, AUTO_CLEAR_CACHE_EXTRA to clearCache)
+      val fragment = PasswordDialog()
+      fragment.arguments = extras
+      return fragment
+    }
   }
 }

app/src/main/res/layout/dialog_password_entry.xml

@@ -27,4 +27,9 @@
     <requestFocus />
   </com.google.android.material.textfield.TextInputLayout>
 
+  <com.google.android.material.checkbox.MaterialCheckBox
+    android:id="@+id/auto_clear_cache"
+    android:layout_width="match_parent"
+    android:text="@string/clear_cached_password_on_screen_off"
+    android:layout_height="wrap_content" />
 </LinearLayout>

app/src/main/res/values/strings.xml

@@ -381,4 +381,5 @@
   <string name="biometric_prompt_title_gpg_passphrase_cache">Unlock passphrase cache</string>
   <string name="aead_detect_title">AEAD encryption detected</string>
   <string name="aead_detect_message">%1$s, see https://passwordstore.app/fix-aead for more information</string>
+  <string name="clear_cached_password_on_screen_off">Clear cached password on screen-off</string>
 </resources>