Persist notification big pictures encrypted

app/src/main/java/se/ajpanton/notificationlog/capture/NotificationCaptureService.kt

@@ -6,6 +6,7 @@ import android.service.notification.NotificationListenerService
 import android.service.notification.StatusBarNotification
 import android.util.Log
 import se.ajpanton.notificationlog.data.EncryptedNotificationLogStore
+import se.ajpanton.notificationlog.data.EncryptedImageStore
 import se.ajpanton.notificationlog.model.NotificationAction
 import se.ajpanton.notificationlog.model.NotificationLogEntry
 import se.ajpanton.notificationlog.settings.LoggingRuleStore
@@ -19,11 +20,13 @@ class NotificationCaptureService : NotificationListenerService() {
     private lateinit var logStore: EncryptedNotificationLogStore
     private lateinit var writeExecutor: ExecutorService
     private lateinit var ruleStore: LoggingRuleStore
+    private lateinit var imageStore: EncryptedImageStore
 
     override fun onCreate() {
         super.onCreate()
         logStore = EncryptedNotificationLogStore(this)
         ruleStore = LoggingRuleStore(this)
+        imageStore = EncryptedImageStore(this)
         writeExecutor = Executors.newSingleThreadExecutor { runnable ->
             Thread(runnable, "notification-log-writer")
         }
@@ -83,6 +86,9 @@ class NotificationCaptureService : NotificationListenerService() {
         )
         writeExecutor.execute {
             try {
+                if (includeContents && snapshot.imageBytes != null && NotificationRuleEvaluator.allows(ruleStore.ruleFor(LoggingType.IMAGE_CONTENT), snapshot.packageName)) {
+                    imageStore.save(entry.id, snapshot.imageBytes)
+                }
                 logStore.append(entry)
             } catch (error: Exception) {
                 Log.e(TAG, "Could not persist notification log entry", error)

app/src/main/java/se/ajpanton/notificationlog/capture/NotificationSnapshot.kt

@@ -1,6 +1,7 @@
 package se.ajpanton.notificationlog.capture
 
 import android.app.Notification
+import android.graphics.Bitmap
 import android.os.Bundle
 import android.service.notification.StatusBarNotification
 
@@ -10,6 +11,7 @@ data class NotificationSnapshot(
     val textContents: String?,
     val hasImage: Boolean,
     val isRoutine: Boolean,
+    val imageBytes: ByteArray?,
 )
 
 object NotificationContents {
@@ -39,6 +41,12 @@ object NotificationContents {
         } == true,
         isRoutine = sbn.notification.extras?.getBoolean(Notification.EXTRA_SHOW_CHRONOMETER, false) == true ||
             sbn.notification.extras?.containsKey(Notification.EXTRA_PROGRESS) == true,
+        imageBytes = sbn.notification.extras?.getParcelable(Notification.EXTRA_PICTURE, Bitmap::class.java)?.let { bitmap ->
+            java.io.ByteArrayOutputStream().use { output ->
+                bitmap.compress(Bitmap.CompressFormat.PNG, 100, output)
+                output.toByteArray()
+            }
+        },
     )
 
     private fun CharSequence.addTo(parts: MutableSet<String>) {

app/src/main/java/se/ajpanton/notificationlog/data/EncryptedImageStore.kt

@@ -0,0 +1,19 @@
+package se.ajpanton.notificationlog.data
+
+import android.content.Context
+import java.io.File
+
+/** Stores copied notification image bytes independently of the source app's URI lifetime. */
+class EncryptedImageStore(context: Context) {
+    private val directory = File(context.filesDir, "notification-images").also(File::mkdirs)
+    private val cipher = AesGcmCipher(LogEncryptionKeyProvider().getOrCreate())
+
+    fun save(id: String, bytes: ByteArray) {
+        val payload = cipher.encrypt(bytes)
+        File(directory, "$id.bin").outputStream().use { output ->
+            output.write(payload.initializationVector.size)
+            output.write(payload.initializationVector)
+            output.write(payload.cipherText)
+        }
+    }
+}