# quic_server_sim.py - Vulnerable QUIC server (simulated handshake)
import socket

def send_quic_initial(conn, addr, server_salt):
    # Respond with a large "server hello" without validating source address
    # In real QUIC, the server must echo the client's token; here we skip that.
    payload = b'\x00' * 1200  # large response
    conn.sendto(payload, addr)

server_socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
server_socket.bind(('0.0.0.0', 4433))
print("QUIC server on :4433")

while True:
    data, addr = server_socket.recvfrom(1024)
    # Vulnerability: respond to any initial packet, no token verification
    send_quic_initial(server_socket, addr, b'salt')