py-edhoc:snake: -- Ephemeral Diffie-Hellman Over COSE

This project provides a Python implementation of the EDHOC key exchange protocol for constrained devices. Currently the protocol is still in draft status at the IETF.

The repository provides an implementation of:

• https://datatracker.ietf.org/doc/html/draft-ietf-lake-edhoc-01
• https://datatracker.ietf.org/doc/html/draft-ietf-lake-edhoc-05

Installation

$ pip install edhoc

Running the test suite

The py-edhoc test suite is based on the official test vectors provided by the LAKE working group.

To run the test suite you'll need pytest:

$ pip install pytest

When you move to the root of the py-edhoc project you can run the test by simply typing:

$ pytest

Supported Cipher Suites

Cipher Suites	COSE algorithms	Support
SUITE 0	(AES-CCM-16-64-128, SHA-256, X25519, EdDSA, Ed25519, AES-CCM-16-64-128, SHA-256)	✔️
SUITE 1	(AES-CCM-16-128-128, SHA-256, X25519, EdDSA, Ed25519, AES-CCM-16-64-128, SHA-256)	✔️
SUITE 2	(AES-CCM-16-64-128, SHA-256, P-256, ES256, P-256, AES-CCM-16-64-128, SHA-256)	❌
SUITE 3	(AES-CCM-16-128-128, SHA-256, P-256, ES256, P-256, AES-CCM-16-64-128, SHA-256)	❌

Authentication Methods

Method	Support
SIGN-SIGN	✔️
STATIC-SIGN	✔️
SIGN-STATIC	✔️
STATIC-STATIC	✔️

Cryptography

The project depends on the python cose package. cose uses pyca/cryptography for all cryptographic operations, except the deterministic ECDSA algorithm. For deterministic ECDSA cose uses python-ecdsa.