---

import socket
import json
import re
import time

HOST = 'tasks.duckerz.ru'
PORT = 30009

def try_full_message(A_value, label):
    """Отправляет полное сообщение с подмененным A."""
    s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    s.settimeout(15.0)
    try:
        s.connect((HOST, PORT))
        data = b""
        while b"Send to Bob:" not in data:
            chunk = s.recv(4096)
            if not chunk:
                break
            data += chunk
        
        text = data.decode('utf-8', errors='ignore')
        match = re.search(r'\{.*\}', text)
        alice = json.loads(match.group())
        
        # Формируем сообщение с подмененным A
        if isinstance(A_value, int):
            A_str = hex(A_value)
        else:
            A_str = A_value
        
        payload = json.dumps({
            "p": alice['p'],
            "g": alice['g'],
            "A": A_str
        })
        
        s.sendall((payload + "\n").encode())
        
        s.settimeout(10.0)
        resp = b""
        try:
            while True:
                chunk = s.recv(4096)
                if not chunk:
                    resp += b"<CLOSED>"
                    break
                resp += chunk
        except socket.timeout:
            resp += b"<TIMEOUT>"
        
        return f"[{label}] {resp.decode('utf-8', errors='ignore')[:200]}"
    except Exception as e:
        return f"[{label}] EXCEPTION: {e}"
    finally:
        s.close()

# Получаем свежие данные
s_temp = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s_temp.settimeout(10.0)
s_temp.connect((HOST, PORT))
data = b""
while b"Send to Bob:" not in data:
    data += s_temp.recv(4096)
text = data.decode('utf-8', errors='ignore')
match = re.search(r'\{.*\}', text)
alice = json.loads(match.group())
s_temp.close()

p = int(alice['p'], 16)
g = int(alice['g'], 16)
A = int(alice['A'], 16)

print(f"[*] p = {p}")
print(f"[*] g = {g}")
print(f"[*] A = {A}")

# Пробуем подменить A
c = 1337
C = pow(g, c, p)  # наш публичный ключ
C_from_A = pow(A, c, p)  # перешифрованный ключ

candidates = [
    (C, "Наш C = g^c mod p"),
    (C_from_A, "C = A^c mod p"),
    (A + 1, "A + 1"),
    (A * 2, "A * 2"),
    (A ^ g, "A XOR g"),
    (1, "1"),
    (0, "0"),
]

print("\n[*] Пробуем отправить полное сообщение с подмененным A. Пауза 20 сек.\n")

for val, label in candidates:
    result = try_full_message(val, label)
    print(result)
    time.sleep(20)

print("\n[*] Готово.")