pypqc: A C repository from James-E-A

Usage

Simply install from PyPI with pip install pypqc, or see "Development" below if you want to tinker on the codebase!

KEMs

McEliece, Kyber, and HQC are currently provided, all with the same interface.:

# Available: hqc_128, hqc_192, hqc_256,
# kyber512, kyber768, kyber1024,
# mceliece348864, mceliece460896,
# mceliece6688128, mceliece6960119, mceliece8192128
from pqc.kem import mceliece6960119 as kemalg


# 1. Keypair generation
pk, sk = kemalg.keypair()


# 2. Key encapsulation
ss, kem_ct = kemalg.encap(pk)


# 3. Key de-encapsulation
ss_result = kemalg.decap(kem_ct, sk)
assert ss_result == ss

Capabilities not included in PQClean, such as McEliece signatures, Hybrid Encryption or KEM-TRANS, and message encapsulation, are not going to be implemented in this library. (Exception: Plaintext Confirmation is on the agenda for inclusion even if upstream ultimately decides to exclude it.)

Signature Algorithms

SPHINCS+, Dilithium, and Falcon are provided, all with the same interface.:

# Available: dilithium2, dilithium3, dilithium5,
# falcon_512, falcon_padded_512, falcon_1024, falcon_padded_1024,
# sphincs_sha2_128f_simple, sphincs_sha2_128s_simple,
# sphincs_shake_128f_simple, sphincs_shake_128s_simple,
# sphincs_sha2_192f_simple, sphincs_sha2_192s_simple,
# sphincs_shake_192f_simple, sphincs_shake_192s_simple,
# sphincs_sha2_256f_simple, sphincs_sha2_256s_simple,
# sphincs_shake_256f_simple, sphincs_shake_256s_simple
from pqc.sign import sphincs_shake_256s_simple as sigalg


# 1. Keypair generation
pk, sk = sigalg.keypair()


# 2. Signing
# (detached signature)
sig = sigalg.sign(MY_MESSAGE, sk)


# 3. Signature verification
# (Returns None on success; raises ValueError on failure.)
sigalg.verify(sig, MY_MESSAGE, pk)

Regarding SPHINCS+: the Simple version is included; the Robust version is is not; SHA256 and SHAKE256 are included; Haraka is not. See PQClean/PQClean#548 (comment) for more information.

Regarding Falcon: the Compressed and Padded versions are included, and are able to verify() each others' signatures. The CT version is not currently planned.

Development

Dependencies:

Python 3 (tested mainly on CPython 3.9, 3.10, 3.11, and 3.12; and on PyPy 7.3.12)
cffi
- Transitive non-PyPI build-time dependency: Python Headers (only Linux users need to manually install these; they come OOtB on Windows. Not sure about Mac.)
setuptools (build-time dependency)
wheel (build-time dependency)
a C compiler (build-time dependency)
- If you're on Windows, https://visualstudio.microsoft.com/visual-cpp-build-tools/
  - If setuptools is having trouble finding your compiler, make sure to first enter the appropriate environment. (For AMD64, this will be "x64 Native Tools Command Prompt for VS 2022"; for 32-bit x86, this will be "Developer Command Prompt for VS 2022"; for other situations, see the documentation.)
- If you're on Mac, reportedly Homebrew is a good choice.
  - It looks like you will also need pkgconfig and libffi, ideally installed via Homebrew, to build this.
- If you're on Linux, install build-essential or 'Development Tools' or something like that.
- (I haven't tested it, but if you're allergic to installing things outside the venv you might be able to use this C compiler...)

Getting started: