Primer paso de la investigacion. Se aportan el .apk, las carpetas con el apk extraido y el apk descompilado. El archivo API_DOCUMENTATION.md es un archivo donde se anotaran los descubrimientos del funcionamiento de la API, y los .py son scripts para probar la funcionalidad de la API con los métodos que vayamos encontrando. Finalmente, los archivos .js son scripts de Frida para extraer informacion de la APP durante la ejecucion.

apk_decompiled/sources/com/google/firebase/messaging/RequestDeduplicator.java

@@ -0,0 +1,56 @@
+package com.google.firebase.messaging;
+
+import android.util.Log;
+import com.google.android.gms.tasks.Continuation;
+import com.google.android.gms.tasks.Task;
+import java.util.Map;
+import java.util.concurrent.Executor;
+
+/* JADX INFO: Access modifiers changed from: package-private */
+/* loaded from: classes3.dex */
+public class RequestDeduplicator {
+    private final Executor executor;
+    private final Map<String, Task<String>> getTokenRequests = new s.j(0);
+
+    /* loaded from: classes3.dex */
+    public interface GetTokenRequest {
+        Task<String> start();
+    }
+
+    /* JADX WARN: Type inference failed for: r0v0, types: [java.util.Map<java.lang.String, com.google.android.gms.tasks.Task<java.lang.String>>, s.j] */
+    public RequestDeduplicator(Executor executor) {
+        this.executor = executor;
+    }
+
+    /* JADX INFO: Access modifiers changed from: private */
+    public /* synthetic */ Task lambda$getOrStartGetTokenRequest$0(String str, Task task) throws Exception {
+        synchronized (this) {
+            this.getTokenRequests.remove(str);
+        }
+        return task;
+    }
+
+    /* JADX WARN: Multi-variable type inference failed */
+    public synchronized Task<String> getOrStartGetTokenRequest(final String str, GetTokenRequest getTokenRequest) {
+        Task<String> task = this.getTokenRequests.get(str);
+        if (task != null) {
+            if (Log.isLoggable(Constants.TAG, 3)) {
+                Log.d(Constants.TAG, "Joining ongoing request for: " + str);
+            }
+            return task;
+        }
+        if (Log.isLoggable(Constants.TAG, 3)) {
+            Log.d(Constants.TAG, "Making new request for: " + str);
+        }
+        Task continueWithTask = getTokenRequest.start().continueWithTask(this.executor, new Continuation() { // from class: com.google.firebase.messaging.m
+            @Override // com.google.android.gms.tasks.Continuation
+            public final Object then(Task task2) {
+                Task lambda$getOrStartGetTokenRequest$0;
+                lambda$getOrStartGetTokenRequest$0 = RequestDeduplicator.this.lambda$getOrStartGetTokenRequest$0(str, task2);
+                return lambda$getOrStartGetTokenRequest$0;
+            }
+        });
+        this.getTokenRequests.put(str, continueWithTask);
+        return continueWithTask;
+    }
+}