Integrate PGPainless backend into the UI properly (#1647)

16 files changed, 378 insertions, 63 deletions

diff --git a/app/src/main/AndroidManifest.xml b/app/src/main/AndroidManifest.xml
index c3ff6302..239cb4f8 100644
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -158,6 +158,8 @@
       android:configChanges="orientation|keyboardHidden"
       android:theme="@style/DialogLikeThemeM3"
       android:windowSoftInputMode="adjustNothing" />
+    <activity android:name=".ui.pgp.PGPKeyImportActivity"
+      android:theme="@style/NoBackgroundThemeM3" />
   </application>
 
 </manifest>
diff --git a/app/src/main/java/dev/msfjarvis/aps/data/crypto/CryptoRepository.kt b/app/src/main/java/dev/msfjarvis/aps/data/crypto/CryptoRepository.kt
new file mode 100644
index 00000000..b0cde380
--- /dev/null
+++ b/app/src/main/java/dev/msfjarvis/aps/data/crypto/CryptoRepository.kt
@@ -0,0 +1,58 @@
+/*
+ * Copyright © 2014-2021 The Android Password Store Authors. All Rights Reserved.
+ * SPDX-License-Identifier: GPL-3.0-only
+ */
+
+package dev.msfjarvis.aps.data.crypto
+
+import com.github.michaelbull.result.runCatching
+import com.github.michaelbull.result.unwrap
+import dev.msfjarvis.aps.crypto.PGPKeyManager
+import dev.msfjarvis.aps.crypto.PGPainlessCryptoHandler
+import dev.msfjarvis.aps.util.extensions.isOk
+import java.io.ByteArrayInputStream
+import java.io.ByteArrayOutputStream
+import javax.inject.Inject
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.withContext
+
+class CryptoRepository
+@Inject
+constructor(
+  private val pgpKeyManager: PGPKeyManager,
+  private val pgpCryptoHandler: PGPainlessCryptoHandler,
+) {
+
+  suspend fun decrypt(
+    password: String,
+    message: ByteArrayInputStream,
+    out: ByteArrayOutputStream,
+  ) {
+    withContext(Dispatchers.IO) { decryptPgp(password, message, out) }
+  }
+
+  suspend fun encrypt(content: ByteArrayInputStream, out: ByteArrayOutputStream) {
+    withContext(Dispatchers.IO) { encryptPgp(content, out) }
+  }
+
+  private suspend fun decryptPgp(
+    password: String,
+    message: ByteArrayInputStream,
+    out: ByteArrayOutputStream,
+  ) {
+    val keys = pgpKeyManager.getAllKeys().unwrap()
+    // Iterates through the keys until the first successful decryption, then returns.
+    keys.first { key ->
+      runCatching { pgpCryptoHandler.decrypt(key, password, message, out) }.isOk()
+    }
+  }
+
+  private suspend fun encryptPgp(content: ByteArrayInputStream, out: ByteArrayOutputStream) {
+    val keys = pgpKeyManager.getAllKeys().unwrap()
+    pgpCryptoHandler.encrypt(
+      keys,
+      content,
+      out,
+    )
+  }
+}
diff --git a/app/src/main/java/dev/msfjarvis/aps/injection/crypto/KeyManagerModule.kt b/app/src/main/java/dev/msfjarvis/aps/injection/crypto/KeyManagerModule.kt
new file mode 100644
index 00000000..0bc1c43d
--- /dev/null
+++ b/app/src/main/java/dev/msfjarvis/aps/injection/crypto/KeyManagerModule.kt
@@ -0,0 +1,38 @@
+/*
+ * Copyright © 2014-2021 The Android Password Store Authors. All Rights Reserved.
+ * SPDX-License-Identifier: GPL-3.0-only
+ */
+
+package dev.msfjarvis.aps.injection.crypto
+
+import android.content.Context
+import dagger.Module
+import dagger.Provides
+import dagger.hilt.InstallIn
+import dagger.hilt.android.qualifiers.ApplicationContext
+import dagger.hilt.components.SingletonComponent
+import dev.msfjarvis.aps.crypto.PGPKeyManager
+import javax.inject.Qualifier
+import kotlinx.coroutines.Dispatchers
+
+@Module
+@InstallIn(SingletonComponent::class)
+object KeyManagerModule {
+  @Provides
+  fun providePGPKeyManager(
+    @PGPKeyDir keyDir: String,
+  ): PGPKeyManager {
+    return PGPKeyManager(
+      keyDir,
+      Dispatchers.IO,
+    )
+  }
+
+  @Provides
+  @PGPKeyDir
+  fun providePGPKeyDir(@ApplicationContext context: Context): String {
+    return context.filesDir.resolve("pgp_keys").absolutePath
+  }
+}
+
+@Qualifier @Retention(AnnotationRetention.RUNTIME) annotation class PGPKeyDir
diff --git a/app/src/main/java/dev/msfjarvis/aps/ui/autofill/AutofillDecryptActivityV2.kt b/app/src/main/java/dev/msfjarvis/aps/ui/autofill/AutofillDecryptActivityV2.kt
index 8f4578cf..697d628d 100644
--- a/app/src/main/java/dev/msfjarvis/aps/ui/autofill/AutofillDecryptActivityV2.kt
+++ b/app/src/main/java/dev/msfjarvis/aps/ui/autofill/AutofillDecryptActivityV2.kt
@@ -21,10 +21,9 @@ import com.github.michaelbull.result.onFailure
 import com.github.michaelbull.result.onSuccess
 import com.github.michaelbull.result.runCatching
 import dagger.hilt.android.AndroidEntryPoint
-import dev.msfjarvis.aps.crypto.Key
+import dev.msfjarvis.aps.data.crypto.CryptoRepository
 import dev.msfjarvis.aps.data.passfile.PasswordEntry
-import dev.msfjarvis.aps.injection.crypto.CryptoSet
-import dev.msfjarvis.aps.ui.crypto.DecryptActivityV2
+import dev.msfjarvis.aps.ui.crypto.PasswordDialog
 import dev.msfjarvis.aps.util.autofill.AutofillPreferences
 import dev.msfjarvis.aps.util.autofill.AutofillResponseBuilder
 import dev.msfjarvis.aps.util.autofill.DirectoryStructure
@@ -33,6 +32,7 @@ import java.io.ByteArrayOutputStream
 import java.io.File
 import javax.inject.Inject
 import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.flow.collectLatest
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
 import logcat.LogPriority.ERROR
@@ -74,7 +74,7 @@ class AutofillDecryptActivityV2 : AppCompatActivity() {
   }
 
   @Inject lateinit var passwordEntryFactory: PasswordEntry.Factory
-  @Inject lateinit var cryptos: CryptoSet
+  @Inject lateinit var repository: CryptoRepository
 
   private lateinit var directoryStructure: DirectoryStructure
 
@@ -98,43 +98,58 @@ class AutofillDecryptActivityV2 : AppCompatActivity() {
     val action = if (isSearchAction) AutofillAction.Search else AutofillAction.Match
     directoryStructure = AutofillPreferences.directoryStructure(this)
     logcat { action.toString() }
+    val dialog = PasswordDialog()
     lifecycleScope.launch {
-      val credentials = decryptCredential(File(filePath))
-      if (credentials == null) {
-        setResult(RESULT_CANCELED)
-      } else {
-        val fillInDataset =
-          AutofillResponseBuilder.makeFillInDataset(
-            this@AutofillDecryptActivityV2,
-            credentials,
-            clientState,
-            action
-          )
-        withContext(Dispatchers.Main) {
-          setResult(
-            RESULT_OK,
-            Intent().apply { putExtra(AutofillManager.EXTRA_AUTHENTICATION_RESULT, fillInDataset) }
-          )
+      withContext(Dispatchers.Main) {
+        dialog.password.collectLatest { value ->
+          if (value != null) {
+            decrypt(File(filePath), clientState, action, value)
+          }
         }
       }
-      withContext(Dispatchers.Main) { finish() }
     }
+    dialog.show(supportFragmentManager, "PASSWORD_DIALOG")
+  }
+
+  private suspend fun decrypt(
+    filePath: File,
+    clientState: Bundle,
+    action: AutofillAction,
+    password: String,
+  ) {
+    val credentials = decryptCredential(filePath, password)
+    if (credentials == null) {
+      setResult(RESULT_CANCELED)
+    } else {
+      val fillInDataset =
+        AutofillResponseBuilder.makeFillInDataset(
+          this@AutofillDecryptActivityV2,
+          credentials,
+          clientState,
+          action
+        )
+      withContext(Dispatchers.Main) {
+        setResult(
+          RESULT_OK,
+          Intent().apply { putExtra(AutofillManager.EXTRA_AUTHENTICATION_RESULT, fillInDataset) }
+        )
+      }
+    }
+    withContext(Dispatchers.Main) { finish() }
   }
 
-  private suspend fun decryptCredential(file: File): Credentials? {
-    runCatching { file.inputStream() }
+  private suspend fun decryptCredential(file: File, password: String): Credentials? {
+    runCatching { file.readBytes().inputStream() }
       .onFailure { e ->
         logcat(ERROR) { e.asLog("File to decrypt not found") }
         return null
       }
       .onSuccess { encryptedInput ->
         runCatching {
-          val crypto = cryptos.first { it.canHandle(file.absolutePath) }
           withContext(Dispatchers.IO) {
             val outputStream = ByteArrayOutputStream()
-            crypto.decrypt(
-              Key(DecryptActivityV2.PRIV_KEY.encodeToByteArray()),
-              DecryptActivityV2.PASS,
+            repository.decrypt(
+              password,
               encryptedInput,
               outputStream,
             )
diff --git a/app/src/main/java/dev/msfjarvis/aps/ui/crypto/DecryptActivityV2.kt b/app/src/main/java/dev/msfjarvis/aps/ui/crypto/DecryptActivityV2.kt
index 799ca32d..33ecdc2b 100644
--- a/app/src/main/java/dev/msfjarvis/aps/ui/crypto/DecryptActivityV2.kt
+++ b/app/src/main/java/dev/msfjarvis/aps/ui/crypto/DecryptActivityV2.kt
@@ -12,11 +12,10 @@ import android.view.MenuItem
 import androidx.lifecycle.lifecycleScope
 import dagger.hilt.android.AndroidEntryPoint
 import dev.msfjarvis.aps.R
-import dev.msfjarvis.aps.crypto.Key
+import dev.msfjarvis.aps.data.crypto.CryptoRepository
 import dev.msfjarvis.aps.data.passfile.PasswordEntry
 import dev.msfjarvis.aps.data.password.FieldItem
 import dev.msfjarvis.aps.databinding.DecryptLayoutBinding
-import dev.msfjarvis.aps.injection.crypto.CryptoSet
 import dev.msfjarvis.aps.ui.adapters.FieldItemAdapter
 import dev.msfjarvis.aps.util.extensions.unsafeLazy
 import dev.msfjarvis.aps.util.extensions.viewBinding
@@ -29,6 +28,7 @@ import kotlin.time.ExperimentalTime
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.delay
 import kotlinx.coroutines.flow.collect
+import kotlinx.coroutines.flow.collectLatest
 import kotlinx.coroutines.flow.onEach
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
@@ -38,7 +38,7 @@ class DecryptActivityV2 : BasePgpActivity() {
 
   private val binding by viewBinding(DecryptLayoutBinding::inflate)
   @Inject lateinit var passwordEntryFactory: PasswordEntry.Factory
-  @Inject lateinit var cryptos: CryptoSet
+  @Inject lateinit var repository: CryptoRepository
   private val relativeParentPath by unsafeLazy { getParentPath(fullPath, repoPath) }
 
   private var passwordEntry: PasswordEntry? = null
@@ -127,16 +127,25 @@ class DecryptActivityV2 : BasePgpActivity() {
   }
 
   private fun decrypt() {
+    val dialog = PasswordDialog()
+    lifecycleScope.launch(Dispatchers.Main) {
+      dialog.password.collectLatest { value ->
+        if (value != null) {
+          decrypt(value)
+        }
+      }
+    }
+    dialog.show(supportFragmentManager, "PASSWORD_DIALOG")
+  }
+
+  private fun decrypt(password: String) {
     lifecycleScope.launch {
-      // TODO(msfjarvis): native methods are fallible, add error handling once out of testing
-      val message = withContext(Dispatchers.IO) { File(fullPath).inputStream() }
+      val message = withContext(Dispatchers.IO) { File(fullPath).readBytes().inputStream() }
       val result =
         withContext(Dispatchers.IO) {
-          val crypto = cryptos.first { it.canHandle(fullPath) }
           val outputStream = ByteArrayOutputStream()
-          crypto.decrypt(
-            Key(PRIV_KEY.encodeToByteArray()),
-            PASS,
+          repository.decrypt(
+            password,
             message,
             outputStream,
           )
@@ -179,10 +188,4 @@ class DecryptActivityV2 : BasePgpActivity() {
       }
     }
   }
-
-  companion object {
-    // TODO(msfjarvis): source these from storage and user input
-    const val PRIV_KEY = ""
-    const val PASS = ""
-  }
 }
diff --git a/app/src/main/java/dev/msfjarvis/aps/ui/crypto/PasswordCreationActivityV2.kt b/app/src/main/java/dev/msfjarvis/aps/ui/crypto/PasswordCreationActivityV2.kt
index ab5b6371..a191ba61 100644
--- a/app/src/main/java/dev/msfjarvis/aps/ui/crypto/PasswordCreationActivityV2.kt
+++ b/app/src/main/java/dev/msfjarvis/aps/ui/crypto/PasswordCreationActivityV2.kt
@@ -36,10 +36,9 @@ import com.google.zxing.integration.android.IntentIntegrator.QR_CODE
 import com.google.zxing.qrcode.QRCodeReader
 import dagger.hilt.android.AndroidEntryPoint
 import dev.msfjarvis.aps.R
-import dev.msfjarvis.aps.crypto.Key
+import dev.msfjarvis.aps.data.crypto.CryptoRepository
 import dev.msfjarvis.aps.data.passfile.PasswordEntry
 import dev.msfjarvis.aps.databinding.PasswordCreationActivityBinding
-import dev.msfjarvis.aps.injection.crypto.CryptoSet
 import dev.msfjarvis.aps.ui.dialogs.DicewarePasswordGeneratorDialogFragment
 import dev.msfjarvis.aps.ui.dialogs.OtpImportDialogFragment
 import dev.msfjarvis.aps.ui.dialogs.PasswordGeneratorDialogFragment
@@ -70,7 +69,7 @@ class PasswordCreationActivityV2 : BasePgpActivity() {
 
   private val binding by viewBinding(PasswordCreationActivityBinding::inflate)
   @Inject lateinit var passwordEntryFactory: PasswordEntry.Factory
-  @Inject lateinit var cryptos: CryptoSet
+  @Inject lateinit var repository: CryptoRepository
 
   private val suggestedName by unsafeLazy { intent.getStringExtra(EXTRA_FILE_NAME) }
   private val suggestedPass by unsafeLazy { intent.getStringExtra(EXTRA_PASSWORD) }
@@ -364,15 +363,10 @@ class PasswordCreationActivityV2 : BasePgpActivity() {
 
       lifecycleScope.launch(Dispatchers.Main) {
         runCatching {
-          val crypto = cryptos.first { it.canHandle(path) }
           val result =
             withContext(Dispatchers.IO) {
               val outputStream = ByteArrayOutputStream()
-              crypto.encrypt(
-                listOf(Key(PUB_KEY.encodeToByteArray())),
-                content.byteInputStream(),
-                outputStream,
-              )
+              repository.encrypt(content.byteInputStream(), outputStream)
               outputStream
             }
           val file = File(path)
@@ -484,7 +478,5 @@ class PasswordCreationActivityV2 : BasePgpActivity() {
     const val EXTRA_EXTRA_CONTENT = "EXTRA_CONTENT"
     const val EXTRA_GENERATE_PASSWORD = "GENERATE_PASSWORD"
     const val EXTRA_EDITING = "EDITING"
-    // TODO(msfjarvis): source this from storage
-    const val PUB_KEY = ""
   }
 }
diff --git a/app/src/main/java/dev/msfjarvis/aps/ui/crypto/PasswordDialog.kt b/app/src/main/java/dev/msfjarvis/aps/ui/crypto/PasswordDialog.kt
new file mode 100644
index 00000000..3542422a
--- /dev/null
+++ b/app/src/main/java/dev/msfjarvis/aps/ui/crypto/PasswordDialog.kt
@@ -0,0 +1,42 @@
+/*
+ * Copyright © 2014-2022 The Android Password Store Authors. All Rights Reserved.
+ * SPDX-License-Identifier: GPL-3.0-only
+ */
+
+package dev.msfjarvis.aps.ui.crypto
+
+import android.app.Dialog
+import android.content.DialogInterface
+import android.os.Bundle
+import androidx.fragment.app.DialogFragment
+import com.google.android.material.dialog.MaterialAlertDialogBuilder
+import dev.msfjarvis.aps.R
+import dev.msfjarvis.aps.databinding.DialogPasswordEntryBinding
+import dev.msfjarvis.aps.util.extensions.finish
+import dev.msfjarvis.aps.util.extensions.unsafeLazy
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.asStateFlow
+
+/** [DialogFragment] to request a password from the user and forward it along. */
+class PasswordDialog : DialogFragment() {
+
+  private val binding by unsafeLazy { DialogPasswordEntryBinding.inflate(layoutInflater) }
+  private val _password = MutableStateFlow<String?>(null)
+  val password = _password.asStateFlow()
+
+  override fun onCreateDialog(savedInstanceState: Bundle?): Dialog {
+    val builder = MaterialAlertDialogBuilder(requireContext())
+    builder.setView(binding.root)
+    builder.setTitle(R.string.password)
+    builder.setPositiveButton(android.R.string.ok) { _, _ ->
+      do {} while (!_password.tryEmit(binding.passwordEditText.text.toString()))
+      dismiss()
+    }
+    return builder.create()
+  }
+
+  override fun onCancel(dialog: DialogInterface) {
+    super.onCancel(dialog)
+    finish()
+  }
+}
diff --git a/app/src/main/java/dev/msfjarvis/aps/ui/pgp/PGPKeyImportActivity.kt b/app/src/main/java/dev/msfjarvis/aps/ui/pgp/PGPKeyImportActivity.kt
new file mode 100644
index 00000000..3cd6930c
--- /dev/null
+++ b/app/src/main/java/dev/msfjarvis/aps/ui/pgp/PGPKeyImportActivity.kt
@@ -0,0 +1,67 @@
+/*
+ * Copyright © 2014-2021 The Android Password Store Authors. All Rights Reserved.
+ * SPDX-License-Identifier: GPL-3.0-only
+ */
+@file:Suppress("BlockingMethodInNonBlockingContext")
+
+package dev.msfjarvis.aps.ui.pgp
+
+import android.os.Bundle
+import androidx.activity.result.contract.ActivityResultContracts.OpenDocument
+import androidx.appcompat.app.AppCompatActivity
+import com.github.michaelbull.result.mapBoth
+import com.github.michaelbull.result.runCatching
+import com.google.android.material.dialog.MaterialAlertDialogBuilder
+import dagger.hilt.android.AndroidEntryPoint
+import dev.msfjarvis.aps.R
+import dev.msfjarvis.aps.crypto.Key
+import dev.msfjarvis.aps.crypto.KeyUtils.tryGetId
+import dev.msfjarvis.aps.crypto.PGPKeyManager
+import javax.inject.Inject
+import kotlinx.coroutines.runBlocking
+
+@AndroidEntryPoint
+class PGPKeyImportActivity : AppCompatActivity() {
+
+  @Inject lateinit var keyManager: PGPKeyManager
+
+  private val pgpKeyImportAction =
+    registerForActivityResult(OpenDocument()) { uri ->
+      runCatching {
+          if (uri == null) {
+            throw IllegalStateException("Selected URI was null")
+          }
+          val keyInputStream =
+            contentResolver.openInputStream(uri)
+              ?: throw IllegalStateException("Failed to open selected file")
+          val bytes = keyInputStream.readBytes()
+          val (key, error) = runBlocking { keyManager.addKey(Key(bytes)) }
+          if (error != null) throw error
+          key
+        }
+        .mapBoth(
+          { key ->
+            require(key != null) { "Key cannot be null here" }
+            MaterialAlertDialogBuilder(this)
+              .setTitle(getString(R.string.pgp_key_import_succeeded))
+              .setMessage(getString(R.string.pgp_key_import_succeeded_message, tryGetId(key)))
+              .setPositiveButton(android.R.string.ok) { _, _ -> finish() }
+              .setOnCancelListener { finish() }
+              .show()
+          },
+          { throwable ->
+            MaterialAlertDialogBuilder(this)
+              .setTitle(getString(R.string.pgp_key_import_failed))
+              .setMessage(throwable.message)
+              .setPositiveButton(android.R.string.ok) { _, _ -> finish() }
+              .setOnCancelListener { finish() }
+              .show()
+          }
+        )
+    }
+
+  override fun onCreate(savedInstanceState: Bundle?) {
+    super.onCreate(savedInstanceState)
+    pgpKeyImportAction.launch(arrayOf("*/*"))
+  }
+}
diff --git a/app/src/main/java/dev/msfjarvis/aps/ui/settings/PGPSettings.kt b/app/src/main/java/dev/msfjarvis/aps/ui/settings/PGPSettings.kt
new file mode 100644
index 00000000..81418ccb
--- /dev/null
+++ b/app/src/main/java/dev/msfjarvis/aps/ui/settings/PGPSettings.kt
@@ -0,0 +1,29 @@
+/*
+ * Copyright © 2014-2021 The Android Password Store Authors. All Rights Reserved.
+ * SPDX-License-Identifier: GPL-3.0-only
+ */
+
+package dev.msfjarvis.aps.ui.settings
+
+import androidx.fragment.app.FragmentActivity
+import de.Maxr1998.modernpreferences.PreferenceScreen
+import de.Maxr1998.modernpreferences.helpers.onClick
+import de.Maxr1998.modernpreferences.helpers.pref
+import dev.msfjarvis.aps.ui.pgp.PGPKeyImportActivity
+import dev.msfjarvis.aps.util.extensions.launchActivity
+
+class PGPSettings(private val activity: FragmentActivity) : SettingsProvider {
+
+  override fun provideSettings(builder: PreferenceScreen.Builder) {
+    builder.apply {
+      pref("_") {
+        title = "Import PGP key"
+        persistent = false
+        onClick {
+          activity.launchActivity(PGPKeyImportActivity::class.java)
+          false
+        }
+      }
+    }
+  }
+}
diff --git a/app/src/main/java/dev/msfjarvis/aps/ui/settings/RepositorySettings.kt b/app/src/main/java/dev/msfjarvis/aps/ui/settings/RepositorySettings.kt
index 8671b5cb..cbd9c18f 100644
--- a/app/src/main/java/dev/msfjarvis/aps/ui/settings/RepositorySettings.kt
+++ b/app/src/main/java/dev/msfjarvis/aps/ui/settings/RepositorySettings.kt
@@ -36,6 +36,7 @@ import dev.msfjarvis.aps.ui.sshkeygen.ShowSshKeyFragment
 import dev.msfjarvis.aps.ui.sshkeygen.SshKeyGenActivity
 import dev.msfjarvis.aps.ui.sshkeygen.SshKeyImportActivity
 import dev.msfjarvis.aps.util.extensions.getString
+import dev.msfjarvis.aps.util.extensions.launchActivity
 import dev.msfjarvis.aps.util.extensions.sharedPrefs
 import dev.msfjarvis.aps.util.extensions.snackbar
 import dev.msfjarvis.aps.util.extensions.unsafeLazy
@@ -59,16 +60,12 @@ class RepositorySettings(private val activity: FragmentActivity) : SettingsProvi
 
   private var showSshKeyPref: Preference? = null
 
-  private fun <T : FragmentActivity> launchActivity(clazz: Class<T>) {
-    activity.startActivity(Intent(activity, clazz))
-  }
-
   private fun selectExternalGitRepository() {
     MaterialAlertDialogBuilder(activity)
       .setTitle(activity.resources.getString(R.string.external_repository_dialog_title))
       .setMessage(activity.resources.getString(R.string.external_repository_dialog_text))
       .setPositiveButton(R.string.dialog_ok) { _, _ ->
-        launchActivity(DirectorySelectionActivity::class.java)
+        activity.launchActivity(DirectorySelectionActivity::class.java)
       }
       .setNegativeButton(R.string.dialog_cancel, null)
       .show()
@@ -89,7 +86,7 @@ class RepositorySettings(private val activity: FragmentActivity) : SettingsProvi
         titleRes = R.string.pref_edit_git_server_settings
         visible = PasswordRepository.isGitRepo()
         onClick {
-          launchActivity(GitServerConfigActivity::class.java)
+          activity.launchActivity(GitServerConfigActivity::class.java)
           true
         }
       }
@@ -97,7 +94,7 @@ class RepositorySettings(private val activity: FragmentActivity) : SettingsProvi
         titleRes = R.string.pref_edit_proxy_settings
         visible = gitSettings.url?.startsWith("https") == true && PasswordRepository.isGitRepo()
         onClick {
-          launchActivity(ProxySelectorActivity::class.java)
+          activity.launchActivity(ProxySelectorActivity::class.java)
           true
         }
       }
@@ -105,7 +102,7 @@ class RepositorySettings(private val activity: FragmentActivity) : SettingsProvi
         titleRes = R.string.pref_edit_git_config
         visible = PasswordRepository.isGitRepo()
         onClick {
-          launchActivity(GitConfigActivity::class.java)
+          activity.launchActivity(GitConfigActivity::class.java)
           true
         }
       }
@@ -113,7 +110,7 @@ class RepositorySettings(private val activity: FragmentActivity) : SettingsProvi
         titleRes = R.string.pref_import_ssh_key_title
         visible = PasswordRepository.isGitRepo()
         onClick {
-          launchActivity(SshKeyImportActivity::class.java)
+          activity.launchActivity(SshKeyImportActivity::class.java)
           true
         }
       }
diff --git a/app/src/main/java/dev/msfjarvis/aps/ui/settings/SettingsActivity.kt b/app/src/main/java/dev/msfjarvis/aps/ui/settings/SettingsActivity.kt
index 26f060ad..d31aa630 100644
--- a/app/src/main/java/dev/msfjarvis/aps/ui/settings/SettingsActivity.kt
+++ b/app/src/main/java/dev/msfjarvis/aps/ui/settings/SettingsActivity.kt
@@ -24,6 +24,7 @@ class SettingsActivity : AppCompatActivity() {
   private val passwordSettings = PasswordSettings(this)
   private val repositorySettings = RepositorySettings(this)
   private val generalSettings = GeneralSettings(this)
+  private val pgpSettings = PGPSettings(this)
 
   private val binding by viewBinding(ActivityPreferenceRecyclerviewBinding::inflate)
   private val preferencesAdapter: PreferencesAdapter
@@ -47,7 +48,7 @@ class SettingsActivity : AppCompatActivity() {
         }
         subScreen {
           titleRes = R.string.pref_category_passwords_title
-          iconRes = R.drawable.ic_lock_open_24px
+          iconRes = R.drawable.ic_password_24px
           passwordSettings.provideSettings(this)
         }
         subScreen {
@@ -60,6 +61,11 @@ class SettingsActivity : AppCompatActivity() {
           iconRes = R.drawable.ic_miscellaneous_services_24px
           miscSettings.provideSettings(this)
         }
+        subScreen {
+          titleRes = R.string.pref_category_pgp_title
+          iconRes = R.drawable.ic_lock_open_24px
+          pgpSettings.provideSettings(this)
+        }
       }
     val adapter = PreferencesAdapter(screen)
     adapter.onScreenChangeListener =
diff --git a/app/src/main/java/dev/msfjarvis/aps/util/extensions/AndroidExtensions.kt b/app/src/main/java/dev/msfjarvis/aps/util/extensions/AndroidExtensions.kt
index 7671adb4..4e045715 100644
--- a/app/src/main/java/dev/msfjarvis/aps/util/extensions/AndroidExtensions.kt
+++ b/app/src/main/java/dev/msfjarvis/aps/util/extensions/AndroidExtensions.kt
@@ -8,6 +8,7 @@ package dev.msfjarvis.aps.util.extensions
 import android.app.KeyguardManager
 import android.content.ClipboardManager
 import android.content.Context
+import android.content.Intent
 import android.content.SharedPreferences
 import android.content.pm.PackageManager
 import android.os.Build
@@ -119,6 +120,11 @@ fun FragmentActivity.snackbar(
   return snackbar
 }
 
+/** Launch an activity denoted by [clazz]. */
+fun <T : FragmentActivity> FragmentActivity.launchActivity(clazz: Class<T>) {
+  startActivity(Intent(this, clazz))
+}
+
 /** Simplifies the common `getString(key, null) ?: defaultValue` case slightly */
 fun SharedPreferences.getString(key: String): String? = getString(key, null)
 
diff --git a/app/src/main/java/dev/msfjarvis/aps/util/extensions/Extensions.kt b/app/src/main/java/dev/msfjarvis/aps/util/extensions/Extensions.kt
index 6c779af6..6e14a29d 100644
--- a/app/src/main/java/dev/msfjarvis/aps/util/extensions/Extensions.kt
+++ b/app/src/main/java/dev/msfjarvis/aps/util/extensions/Extensions.kt
@@ -4,6 +4,9 @@
  */
 package dev.msfjarvis.aps.util.extensions
 
+import com.github.michaelbull.result.Err
+import com.github.michaelbull.result.Ok
+import com.github.michaelbull.result.Result
 import com.github.michaelbull.result.getOrElse
 import com.github.michaelbull.result.runCatching
 import dev.msfjarvis.aps.data.repo.PasswordRepository
@@ -82,3 +85,13 @@ fun <T> unsafeLazy(initializer: () -> T) = lazy(LazyThreadSafetyMode.NONE) { ini
 
 /** A convenience extension to turn a [Throwable] with a message into a loggable string. */
 fun Throwable.asLog(message: String): String = "$message\n${asLog()}"
+
+/** Extension on [Result] that returns if the type is [Ok] */
+fun <V, E> Result<V, E>.isOk(): Boolean {
+  return this is Ok<V>
+}
+
+/** Extension on [Result] that returns if the type is [Err] */
+fun <V, E> Result<V, E>.isErr(): Boolean {
+  return this is Err<E>
+}
diff --git a/app/src/main/res/drawable/ic_password_24px.xml b/app/src/main/res/drawable/ic_password_24px.xml
new file mode 100644
index 00000000..a41a383a
--- /dev/null
+++ b/app/src/main/res/drawable/ic_password_24px.xml
@@ -0,0 +1,14 @@
+<!--
+  ~ Copyright © 2014-2021 The Android Password Store Authors. All Rights Reserved.
+  ~ SPDX-License-Identifier: GPL-3.0-only
+  -->
+
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="24"
+    android:viewportHeight="24">
+  <path
+      android:pathData="M2,17h20v2H2V17zM3.15,12.95L4,11.47l0.85,1.48l1.3,-0.75L5.3,10.72H7v-1.5H5.3l0.85,-1.47L4.85,7L4,8.47L3.15,7l-1.3,0.75L2.7,9.22H1v1.5h1.7L1.85,12.2L3.15,12.95zM9.85,12.2l1.3,0.75L12,11.47l0.85,1.48l1.3,-0.75l-0.85,-1.48H15v-1.5h-1.7l0.85,-1.47L12.85,7L12,8.47L11.15,7l-1.3,0.75l0.85,1.47H9v1.5h1.7L9.85,12.2zM23,9.22h-1.7l0.85,-1.47L20.85,7L20,8.47L19.15,7l-1.3,0.75l0.85,1.47H17v1.5h1.7l-0.85,1.48l1.3,0.75L20,11.47l0.85,1.48l1.3,-0.75l-0.85,-1.48H23V9.22z"
+      android:fillColor="#000000"/>
+</vector>
diff --git a/app/src/main/res/layout/dialog_password_entry.xml b/app/src/main/res/layout/dialog_password_entry.xml
new file mode 100644
index 00000000..3729fb4f
--- /dev/null
+++ b/app/src/main/res/layout/dialog_password_entry.xml
@@ -0,0 +1,29 @@
+<?xml version="1.0" encoding="utf-8"?><!--
+  ~ Copyright © 2014-2022 The Android Password Store Authors. All Rights Reserved.
+  ~ SPDX-License-Identifier: GPL-3.0-only
+  -->
+
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+  xmlns:app="http://schemas.android.com/apk/res-auto"
+  android:layout_width="match_parent"
+  android:layout_height="match_parent"
+  android:orientation="vertical"
+  android:padding="@dimen/activity_horizontal_margin">
+
+  <com.google.android.material.textfield.TextInputLayout
+    android:id="@+id/password_field"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:hint="@string/password"
+    app:endIconMode="password_toggle"
+    app:hintAnimationEnabled="true"
+    app:hintEnabled="true">
+
+    <com.google.android.material.textfield.TextInputEditText
+      android:id="@+id/password_edit_text"
+      android:layout_width="match_parent"
+      android:layout_height="wrap_content"
+      android:inputType="textPassword" />
+  </com.google.android.material.textfield.TextInputLayout>
+
+</LinearLayout>
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index b2eda6fa..432ee6ea 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -390,5 +390,9 @@
   <string name="gpg_key_select_mandatory">Selecting a GPG key is necessary to proceed</string>
   <string name="place_shortcut_on_home_screen">Place shortcut on home screen</string>
   <string name="password_list_fab_content_description">Create new password or folder</string>
+  <string name="pgp_key_import_failed">Failed to import PGP key</string>
+  <string name="pgp_key_import_succeeded">Successfully imported PGP key</string>
+  <string name="pgp_key_import_succeeded_message">The key ID of the imported key is given below, please review it for correctness:\n%1$s</string>
+  <string name="pref_category_pgp_title">PGP settings</string>
 
 </resources>