Error parsing message with type 'SignedLicenseRequest'

Helpers/Device.py

@@ -0,0 +1,94 @@
+import os
+import logging
+import base64
+import frida
+from Crypto.PublicKey import RSA
+from Helpers.wv_proto2_pb2 import SignedLicenseRequest
+
+
+class Device:
+    def __init__(self, dynamic_function_name, cdm_version, module_names):
+        self.logger = logging.getLogger(__name__)
+        self.saved_keys = {}
+        self.widevine_libraries = module_names
+        self.usb_device = frida.get_usb_device()
+        self.name = self.usb_device.name
+
+        with open('./Helpers/script.js', 'r', encoding="utf_8") as script:
+            self.frida_script = script.read()
+        self.frida_script = self.frida_script.replace(r'${DYNAMIC_FUNCTION_NAME}', dynamic_function_name)
+        self.frida_script = self.frida_script.replace(r'${CDM_VERSION}', cdm_version)
+
+    def export_key(self, key, client_id):
+        save_dir = os.path.join(
+            'key_dumps',
+            f'{self.name}',
+            'private_keys',
+            f'{client_id.Token._DeviceCertificate.SystemId}',
+            f'{str(key.n)[:10]}'
+        )
+
+        if not os.path.exists(save_dir):
+            os.makedirs(save_dir)
+
+        with open(os.path.join(save_dir, 'client_id.bin'), 'wb+') as writer:
+            writer.write(client_id.SerializeToString())
+
+        with open(os.path.join(save_dir, 'private_key.pem'), 'wb+') as writer:
+            writer.write(key.exportKey('PEM'))
+        self.logger.info('Key pairs saved at %s', save_dir)
+
+    def on_message(self, msg, data):
+        if 'payload' in msg:
+            if msg['payload'] == 'private_key':
+                key = RSA.import_key(data)
+                if key.n not in self.saved_keys:
+                    self.logger.debug(
+                        'Retrieved key: \n\n%s\n',
+                        key.export_key().decode("utf-8")
+                    )
+                self.saved_keys[key.n] = key
+            elif msg['payload'] == 'device_info':
+                self.license_request_message(data)
+            elif msg['payload'] == 'message_info':
+                self.logger.info(data.decode())
+
+    def license_request_message(self, data):
+        self.logger.debug(
+            'Retrieved build info: \n\n%s\n',
+            base64.b64encode(data).decode('utf-8')
+        )
+        root = SignedLicenseRequest()
+        root.ParseFromString(data)
+        public_key = root.Msg.ClientId.Token._DeviceCertificate.PublicKey
+        key = RSA.importKey(public_key)
+        cur = self.saved_keys.get(key.n)
+
+        if cur is not None:
+            self.export_key(cur, root.Msg.ClientId)
+
+    def find_widevine_process(self, process_name):
+        process = self.usb_device.attach(process_name)
+        script = process.create_script(self.frida_script)
+        script.load()
+        loaded_modules = []
+        try:
+            for lib in self.widevine_libraries:
+                try:
+                    loaded_modules.append(script.exports.getmodulebyname(lib))
+                except frida.core.RPCException as e:
+                    # Hide the cases where the module cannot be found
+                    continue
+                except Exception as e:
+                    raise(e)
+        finally:
+            process.detach()
+            return loaded_modules
+
+    def hook_to_process(self, process, library):
+        session = self.usb_device.attach(process)
+        script = session.create_script(self.frida_script)
+        script.on('message', self.on_message)
+        script.load()
+        script.exports.hooklibfunctions(library)
+        return session