#!/usr/bin/env python3
import base64


def xor_decrypt(data, key):
    """XOR decrypt bytes with key"""
    result = []
    key_bytes = key.encode('utf-8')
    key_len = len(key_bytes)
    
    for i, byte in enumerate(data):
        result.append(byte ^ key_bytes[i % key_len])
    
    return bytes(result)


# Read the payload from file
with open('payload.txt', 'r') as f:
    payload = f.read().strip()

print(f"Payload length: {len(payload)} characters")

# Base64 decode first
try:
    decoded_base64 = base64.b64decode(payload)
    print(f"Base64 decoded to {len(decoded_base64)} bytes")

    # Then XOR decrypt with key
    decrypted = xor_decrypt(decoded_base64.decode('latin-1'), "ph15h1n9")

    print("\nFlag found:")
    print(decrypted)
except Exception as e:
    print(f"Error: {e}")