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/Store.java

@@ -0,0 +1,127 @@
+package com.google.firebase.messaging;
+
+import android.content.Context;
+import android.content.SharedPreferences;
+import android.text.TextUtils;
+import android.util.Log;
+import java.io.File;
+import java.io.IOException;
+import java.util.concurrent.TimeUnit;
+import org.json.JSONException;
+import org.json.JSONObject;
+
+/* JADX INFO: Access modifiers changed from: package-private */
+/* loaded from: classes3.dex */
+public class Store {
+    static final String NO_BACKUP_FILE = "com.google.android.gms.appid-no-backup";
+    static final String PREFERENCES = "com.google.android.gms.appid";
+    private static final String SCOPE_ALL = "*";
+    private static final String STORE_KEY_TOKEN = "|T|";
+    final SharedPreferences store;
+
+    /* loaded from: classes3.dex */
+    public static class Token {
+        private static final String KEY_APP_VERSION = "appVersion";
+        private static final String KEY_TIMESTAMP = "timestamp";
+        private static final String KEY_TOKEN = "token";
+        private static final long REFRESH_PERIOD_MILLIS = TimeUnit.DAYS.toMillis(7);
+        final String appVersion;
+        final long timestamp;
+        final String token;
+
+        private Token(String str, String str2, long j4) {
+            this.token = str;
+            this.appVersion = str2;
+            this.timestamp = j4;
+        }
+
+        public static String encode(String str, String str2, long j4) {
+            try {
+                JSONObject jSONObject = new JSONObject();
+                jSONObject.put("token", str);
+                jSONObject.put("appVersion", str2);
+                jSONObject.put(KEY_TIMESTAMP, j4);
+                return jSONObject.toString();
+            } catch (JSONException e4) {
+                Log.w(Constants.TAG, "Failed to encode token: " + e4);
+                return null;
+            }
+        }
+
+        public static Token parse(String str) {
+            if (TextUtils.isEmpty(str)) {
+                return null;
+            }
+            if (!str.startsWith("{")) {
+                return new Token(str, null, 0L);
+            }
+            try {
+                JSONObject jSONObject = new JSONObject(str);
+                return new Token(jSONObject.getString("token"), jSONObject.getString("appVersion"), jSONObject.getLong(KEY_TIMESTAMP));
+            } catch (JSONException e4) {
+                Log.w(Constants.TAG, "Failed to parse token: " + e4);
+                return null;
+            }
+        }
+
+        public boolean needsRefresh(String str) {
+            return System.currentTimeMillis() > this.timestamp + REFRESH_PERIOD_MILLIS || !str.equals(this.appVersion);
+        }
+    }
+
+    public Store(Context context) {
+        this.store = context.getSharedPreferences(PREFERENCES, 0);
+        checkForRestore(context, NO_BACKUP_FILE);
+    }
+
+    private void checkForRestore(Context context, String str) {
+        File file = new File(D.h.getNoBackupFilesDir(context), str);
+        if (file.exists()) {
+            return;
+        }
+        try {
+            if (!file.createNewFile() || isEmpty()) {
+                return;
+            }
+            Log.i(Constants.TAG, "App restored, clearing state");
+            deleteAll();
+        } catch (IOException e4) {
+            if (Log.isLoggable(Constants.TAG, 3)) {
+                Log.d(Constants.TAG, "Error creating file in no backup dir: " + e4.getMessage());
+            }
+        }
+    }
+
+    private String createTokenKey(String str, String str2) {
+        return str + STORE_KEY_TOKEN + str2 + "|*";
+    }
+
+    public synchronized void deleteAll() {
+        this.store.edit().clear().commit();
+    }
+
+    public synchronized void deleteToken(String str, String str2) {
+        String createTokenKey = createTokenKey(str, str2);
+        SharedPreferences.Editor edit = this.store.edit();
+        edit.remove(createTokenKey);
+        edit.commit();
+    }
+
+    public synchronized Token getToken(String str, String str2) {
+        return Token.parse(this.store.getString(createTokenKey(str, str2), null));
+    }
+
+    public synchronized boolean isEmpty() {
+        return this.store.getAll().isEmpty();
+    }
+
+    public synchronized void saveToken(String str, String str2, String str3, String str4) {
+        String encode = Token.encode(str3, str4, System.currentTimeMillis());
+        if (encode == null) {
+            return;
+        }
+        SharedPreferences.Editor edit = this.store.edit();
+        edit.putString(createTokenKey(str, str2), encode);
+        edit.commit();
+    }
+}