Cannot resend the same intent (security issue when sharing)

Author: bmarty

vector/src/main/java/im/vector/app/features/MainActivity.kt

@@ -83,6 +83,7 @@ class MainActivity : VectorBaseActivity<ActivityMainBinding>(), UnlockedActivity
     companion object {
         private const val EXTRA_ARGS = "EXTRA_ARGS"
         private const val EXTRA_NEXT_INTENT = "EXTRA_NEXT_INTENT"
+        private const val EXTRA_INIT_SESSION = "EXTRA_INIT_SESSION"
 
         // Special action to clear cache and/or clear credentials
         fun restartApp(activity: Activity, args: MainActivityArgs) {
@@ -93,6 +94,12 @@ class MainActivity : VectorBaseActivity<ActivityMainBinding>(), UnlockedActivity
             activity.startActivity(intent)
         }
 
+        fun getIntentToInitSession(activity: Activity): Intent {
+            val intent = Intent(activity, MainActivity::class.java)
+            intent.putExtra(EXTRA_INIT_SESSION, true)
+            return intent
+        }
+
         fun getIntentWithNextIntent(context: Context, nextIntent: Intent): Intent {
             val intent = Intent(context, MainActivity::class.java)
             intent.putExtra(EXTRA_NEXT_INTENT, nextIntent)
@@ -151,6 +158,9 @@ class MainActivity : VectorBaseActivity<ActivityMainBinding>(), UnlockedActivity
             // Start the next Activity
             val nextIntent = intent.getParcelableExtra<Intent>(EXTRA_NEXT_INTENT)
             startIntentAndFinish(nextIntent)
+        } else if (intent.hasExtra(EXTRA_INIT_SESSION)) {
+            setResult(RESULT_OK)
+            finish()
         } else {
             args = parseArgs()
             if (args.clearCredentials || args.isUserLoggedOut || args.clearCache) {

vector/src/main/java/im/vector/app/features/link/LinkHandlerActivity.kt

@@ -26,6 +26,7 @@ import dagger.hilt.android.AndroidEntryPoint
 import im.vector.app.R
 import im.vector.app.core.di.ActiveSessionHolder
 import im.vector.app.core.error.ErrorFormatter
+import im.vector.app.core.extensions.registerStartForActivityResult
 import im.vector.app.core.platform.VectorBaseActivity
 import im.vector.app.core.utils.toast
 import im.vector.app.databinding.ActivityProgressBinding
@@ -57,13 +58,20 @@ class LinkHandlerActivity : VectorBaseActivity<ActivityProgressBinding>() {
         handleIntent()
     }
 
+    private val launcher = registerStartForActivityResult {
+        if (it.resultCode == RESULT_OK) {
+            handleIntent()
+        } else {
+            // User has pressed back on the MainActivity, so finish also this one.
+            finish()
+        }
+    }
+
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
 
         if (startAppViewModel.shouldStartApp()) {
-            // Start MainActivity, providing current Intent has next intent
-            startActivity(MainActivity.getIntentWithNextIntent(this, intent))
-            finish()
+            launcher.launch(MainActivity.getIntentToInitSession(this))
         } else {
             handleIntent()
         }

vector/src/main/java/im/vector/app/features/share/IncomingShareActivity.kt

@@ -22,6 +22,7 @@ import com.airbnb.mvrx.viewModel
 import dagger.hilt.android.AndroidEntryPoint
 import im.vector.app.core.di.ActiveSessionHolder
 import im.vector.app.core.extensions.addFragment
+import im.vector.app.core.extensions.registerStartForActivityResult
 import im.vector.app.core.platform.VectorBaseActivity
 import im.vector.app.databinding.ActivitySimpleBinding
 import im.vector.app.features.MainActivity
@@ -35,13 +36,20 @@ class IncomingShareActivity : VectorBaseActivity<ActivitySimpleBinding>() {
 
     @Inject lateinit var activeSessionHolder: ActiveSessionHolder
 
+    private val launcher = registerStartForActivityResult {
+        if (it.resultCode == RESULT_OK) {
+            handleAppStarted()
+        } else {
+            // User has pressed back on the MainActivity, so finish also this one.
+            finish()
+        }
+    }
+
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
 
         if (startAppViewModel.shouldStartApp()) {
-            // Start MainActivity, providing current Intent has next intent
-            startActivity(MainActivity.getIntentWithNextIntent(this, intent))
-            finish()
+            launcher.launch(MainActivity.getIntentToInitSession(this))
         } else {
             handleAppStarted()
         }