pymceliece

A Python wrapper for the libmceliece microlibrary

Installation

Dependencies

pymceliece depends only on libmceliece (which also depends on libcpucycles and librandombytes), available here

API

Instantiated parameters

The API follows the libmceliece API. It implements the following parameter sets:

• mceliece8192128
• mceliece6960119
• mceliece6688128
• mceliece8192128
• mceliece460896
• mceliece348864
• mceliece6960119f
• mceliece6688128f
• mceliece8192128f
• mceliece460896f
• mceliece348864f

Each has the following constants defined:

• mceliecexxxxxxx.PUBLICKEYBYTES Length of the public key
• mceliecexxxxxxx.SECRETKEYBYTES Length of the private key
• mceliecexxxxxxx.CIPHERTEXTBYTES Length of the ciphertext
• mceliecexxxxxxx.BYTES Length of the session key

Usage

For each instantiation the following functions are available:

mcelieceXXXXXXX.keypair() -> Tuple[bytes, bytes]

Randomly generates a McEliece secret key and its corresponding public key.

Example:

>>> from pymceliece import mceliece6960119
>>> pk, sk = mceliece6960119.keypair()

mcelieceXXXXXXX.enc(pk: bytes) -> Tuple[bytes, bytes]

Randomly generates a ciphertext and the corresponding session key given a public key pk.

Example:

>>> from pymceliece import mceliece8192128f
>>> pk, _ = mceliece8192128f.keypair()
>>> c, k = mceliece8192128f.enc(pk)

mcelieceXXXXXXX.dec(c: bytes, pk: bytes) -> bytes

Given a McEliece secret key sk and a ciphertext c encapsulated to sk's corresponding public key pk, computes the session key k.

Example:

>>> from pymceliece import mceliece348864f
>>> pk, sk = mceliece348864f.keypair()
>>> c, k = mceliece348864f.enc(pk)
>>> mceliece348864f.dec(c, sk) == k
True