Rubenesque is an implementation of several standard elliptic curve groups in pure Python 3 used for cryptographic purposes. The classes contained in this source code should be sufficient to implement your own cryptographic primitives.
However, please note that, due to the nature of the Python programming language, this code cannot guarantee either performance or safety from side-channel attacks. Using this library in situations where such properties are required is not advised and may actively lead to security compromise. Although this project will accept patches to improve performance, we will not consider performance or side-channel avoidance as valid bugs.
Rubenesque does, however, strive to be correct and standards compliant. This makes it useful in a variety of scenarios; especially use cases such as offline cryptography or unit tests against servers programmed in lower level languages.
Rubenesque currently implements the following curves:
- brainpoolP160r1
- brainpoolP192r1
- brainpoolP224r1
- brainpoolP256r1
- brainpoolP320r1
- brainpoolP384r1
- brainpoolP512r1
- edwards25519
- edwards448
- MDC201601
- secp192r1
- secp224r1
- secp256r1
- secp384r1
- secp521r1
Here is a simple example of doing ECDH with SEC P256 using SEC1 encoding.
Both sides prepare for the exchange by loading the same curve and encoding:
>>> from rubenesque.codecs.sec import encode, decode
>>> import rubenesque.curves
>>> secp256r1 = rubenesque.curves.find('secp256r1')
Alice generates her private and public keys:
>>> alice_prv = secp256r1.private_key()
>>> alice_pub = secp256r1.generator() * alice_prv
>>> alice_enc = encode(alice_pub)
Bob does the same:
>>> bob_prv = secp256r1.private_key()
>>> bob_pub = secp256r1.generator() * bob_prv
>>> bob_enc = encode(bob_pub)
After exchanging their encoded keys, Alice computes the session key:
>>> alice_ses = decode(secp256r1, bob_enc) * alice_prv
Bob does the same:
>>> bob_ses = decode(secp256r1, alice_enc) * bob_prv
Notice that Bob and Alice share the same session key, but not private key:
>>> alice_prv == bob_prv
False
>>> alice_ses == bob_ses
True
Rubenesque is licensed under the BSD 2-Clause license.