Spectral is algorithm for authenticated encryption with associated data; it uses Speck in CTR mode as the underlying cipher (with a 128-bit block size and a 128-bit key size) along with HMAC-SHA256 in an Encrypt-then-MAC construction.
This package provides tested, performant Python 3 CFFI bindings to an implementation of Spectral, including abstractions for simplified encryption and decryption.
You can install this package using pip or the included setup.py script:
# Using pip
pip install spectral-aead
# Using setup.py
python setup.py install
from spectral import *
# Demonstration key, nonce, plaintext and associated data
key = b"\0" * spectral.KEY_SIZE
nonce = b"\0" * spectral.NONCE_SIZE
plaintext = b"\0" * 16
associated = b"\0" * 16
# Spectral simplified encryption
encrypted = encrypt(key, plaintext, associated) # Associated data is optional
# Spectral simplified decryption
computed_plaintext = decrypt(key, encrypted, associated) # Raises RuntimeError if any parameter has been tampered with
assert plaintext == computed_plaintext
# Spectral disjoint encryption
ciphertext, mac = encrypt_disjoint(key, nonce, plaintext, associated) # Associated data is optional
# Spectral disjoint decryption
computed_plaintext = decrypt_disjoint(key, nonce, ciphertext, mac, associated) # Raises RuntimeError if any parameter has been tampered with
assert plaintext == computed_plaintextBSD 3-Clause License
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