NewHope is a key exchange protocol based on the Ring-Learning-with-Errors (Ring-LWE) problem and a round 2 candidate submission in the Post-Quantum Cryptography Standardization project organised by NIST.
This package provides tested, performant Python 3 CFFI bindings to the NewHope reference implementation with minor, cautious adjustments for cross-platform compatibility.
You can install this package using pip or the included setup.py script:
# Using pip
pip install newhope-cffi
# Using setup.py
python setup.py install
from newhope import generate_keypair, encrypt, decrypt
from secrets import compare_digest
# Alice generates a public key
public_key, secret_key = generate_keypair()
# Bob derives a secret (the plaintext) and encrypts it with Alice's public key to produce a ciphertext
ciphertext, plaintext_original = encrypt(public_key)
# Alice decrypts Bob's ciphertext to derive the now shared secret
plaintext_recovered = decrypt(secret_key, ciphertext)
# Compare the original and recovered secrets in constant time
assert compare_digest(plaintext_original, plaintext_recovered)BSD 3-Clause License
Copyright (c) 2018, Phil Demetriou
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