luigoalma / haccrypto

Nintendo Switch XTSN crypto for Python

haccrypto

haccrypto is the Nintendo Switch XTSN crypto for Python, originally from ninfs and now standalone.

Usage

You can import XTSN class and parse_biskeydump method from haccrypto.crypto. XTSN requires the crypt key and tweak when declaring an instance of it, it will provide you with the encrypt and decrypt methods. parse_biskeydump will provide you with crypt keys and tweaks from a bis key dump.

Example usage

# import the crypto module
from haccrypto.crypto import parse_biskeydump, XTSN

# getting your bis keys
# returns a list of 4 lists, each list containing crypt and tweak, for bis keys 0 to 3 
with open("switch-keys.txt", "r") as o:
	bis_keys = parse_biskeydump(o.read())

# lets use bis key 0's crypt and tweak
bis0xtsn = XTSN(bis_keys[0][0], bis_keys[0][1])

# lets see it in action
# lets encrypt a 0 filled buffer of bytes
# and let's say its from sector offset 0, for example sake
# default sector size = 0x200
zeros = b'\0'*32

enc_zeros = bis0xtsn.encrypt(zeros, 0)

# now lets decrypt, got to tell the same sector offset
# internal key and tweak are still the same
dec_zeros = bis0xtsn.decrypt(enc_zeros, 0)

# this should be always true
# otherwise there's something wrong
# that can happen if the openssl dll provided is not proper, or something arbitrary happened
if zeros == dec_zeros:
	print("XTSN ran correctly!")
else:
	print("XTSN has made a bad crypto operation.")

Licenses

• haccrypto is under the MIT license.
  • hac/aes.cpp and hac/aes.hpp are from @openluopworld's aes_128 commit b5b7f55, and uses the MIT License.
  • hac/_crypto.cpp AES-XTS part by me(@luigoalma), based on @plutooo's crypto module.
  • hac/crypto.py written by @ihaveamac, falls under MIT license as well.