Decrypt ruckus backups, debug info files, etc.

decrypt_ruckus.py

#!/usr/bin/env python3
"""
Decrypt Ruckus Unleashed encrypted files
Algorithm source: https://ms264556.net/ruckus/DecryptRuckusBackups
"""
import struct, sys, os

def ruckus_decrypt(input_path, output_path):
    (xor_int, xor_flip) = struct.unpack('QQ', b')\x1aB\x05\xbd,\xd6\xf25\xad\xb8\xe0?T\xc58')
    structInt8 = struct.Struct('Q')

    with open(input_path, "rb") as f_in, open(output_path, "wb") as f_out:
        data = f_in.read()
        prev = 0
        for block in struct.unpack_from(str(len(data) // 8) + "Q", data):
            out = structInt8.pack(prev ^ xor_int ^ block)
            xor_int ^= xor_flip
            prev = block
            f_out.write(out)

        padding = out[-1] & 0xf
        if padding:
            f_out.seek(-padding, os.SEEK_END)
            f_out.truncate()

if __name__ == "__main__":
    if len(sys.argv) < 2:
        print(f"Usage: {sys.argv[0]} <encrypted_file> [output]")
        sys.exit(1)
    output = sys.argv[2] if len(sys.argv) >= 3 else sys.argv[1] + ".decrypted"
    ruckus_decrypt(sys.argv[1], output)
    print(f"Decrypted: {output}")