import os import json import base64 import os.path as path class Module: def __init__(self, incoming=False, verbose=False, options=None): # extract the file name from __file__. __file__ is proxymodules/name.py self.name = path.splitext(path.basename(__file__))[0] self.description = 'Simply print the received data as text' self.incoming = incoming # incoming means module is on -im chain self.find = None # if find is not None, this text will be highlighted # protocol 1: flag{m4n_1n_th3_m1ddl3_w0w} def execute(self, data): print(f"Incoming data: {data}") data_json = json.loads(data) # return handshake messages without modification if data_json.get("type") == "HANDSHAKE": return data # replace "Bob" with "Eve" in the first protocol message elif data_json.get("id") == 1: data_json["content"] = data_json["content"].replace("Bob","Eve") # if message 3 received, build valid message 4 # instead of {Hello Alice!}_K use arbitary data elif data_json.get("id") == 3: data_json["id"] = 4 data_json["sender"] = "Bob" data_json["receiver"] = "Alice" data_json["content"] = str(base64.b64encode(os.urandom(16))) # dump message data = json.dumps(data_json) + "\n" print(f"Outgoing data: {data}") # return crafted message to proxy return data if __name__ == '__main__': print('This module is not supposed to be executed alone!')