pyhpke 0.3.0

A Python implementation of HPKE.

PyHPKE - A Python implementation of HPKE

PyHPKE is a HPKE (Hybrid Public Key Encryption) implementation written in Python.

You can install PyHPKE with pip:

$ pip install pyhpke

And then, you can use it as follows:

from pyhpke import AEADId, CipherSuite, KDFId, KEMId, KEMKey

# The sender side:
suite_s = CipherSuite.new(KEMId.DHKEM_P256_HKDF_SHA256, KDFId.HKDF_SHA256, AEADId.AES128_GCM)
pkr = KEMKey.from_jwk(  # from_pem is also available.
    {
        "kid": "01",
        "kty": "EC",
        "crv": "P-256",
        "x": "Ze2loSV3wrroKUN_4zhwGhCqo3Xhu1td4QjeQ5wIVR0",
        "y": "HlLtdXARY_f55A3fnzQbPcm6hgr34Mp8p-nuzQCE0Zw",
    }
)
enc, sender = suite_s.create_sender_context(pkr)
ct = sender.seal(b"Hello world!")

# The recipient side:
suite_r = CipherSuite.new(KEMId.DHKEM_P256_HKDF_SHA256, KDFId.HKDF_SHA256, AEADId.AES128_GCM)
skr = KEMKey.from_jwk(
    {
        "kid": "01",
        "kty": "EC",
        "crv": "P-256",
        "x": "Ze2loSV3wrroKUN_4zhwGhCqo3Xhu1td4QjeQ5wIVR0",
        "y": "HlLtdXARY_f55A3fnzQbPcm6hgr34Mp8p-nuzQCE0Zw",
        "d": "r_kHyZ-a06rmxM3yESK84r1otSg-aQcVStkRhA-iCM8",
    }
)
recipient = suite_r.create_recipient_context(enc, skr)
pt = recipient.open(ct)

assert pt == b"Hello world!"

Index

• Installation
• Supported HPKE Modes and Cipher Suites
• Usage
• API Reference
• Test
• Contributing

Installation

You can install PySETO with pip:

$ pip install pyseto

Supported HPKE Modes and Cipher Suites

Modes

Base	PSK	Auth	AuthPSK
✅	✅	✅	✅

Key Encapsulation Machanisms (KEMs)

KEMs
DHKEM (P-256, HKDF-SHA256)	✅
DHKEM (P-384, HKDF-SHA384)	✅
DHKEM (P-521, HKDF-SHA512)	✅
DHKEM (X25519, HKDF-SHA256)	✅
DHKEM (X448, HKDF-SHA512)	✅

Key Derivation Functions (KDFs)

KDFs
HKDF-SHA256	✅
HKDF-SHA384	✅
HKDF-SHA512	✅

Authenticated Encryption with Associated Data (AEAD) Functions

AEADs
AES-128-GCM	✅
AES-256-GCM	✅
ChaCha20Poly1305	✅
Export Only	✅

Usage

from pyhpke import AEADId, CipherSuite, KDFId, KEMId, KEMKey

# The sender side:
suite_s = CipherSuite.new(KEMId.DHKEM_P256_HKDF_SHA256, KDFId.HKDF_SHA256, AEADId.AES128_GCM)
pkr = KEMKey.from_jwk(
    {
        "kid": "01",
        "kty": "EC",
        "crv": "P-256",
        "x": "Ze2loSV3wrroKUN_4zhwGhCqo3Xhu1td4QjeQ5wIVR0",
        "y": "HlLtdXARY_f55A3fnzQbPcm6hgr34Mp8p-nuzQCE0Zw",
    }
)
enc, sender = suite_s.create_sender_context(pkr)
ct = sender.seal(b"Hello world!")

# The recipient side:
suite_r = CipherSuite.new(KEMId.DHKEM_P256_HKDF_SHA256, KDFId.HKDF_SHA256, AEADId.AES128_GCM)
skr = KEMKey.from_jwk(
    {
        "kid": "01",
        "kty": "EC",
        "crv": "P-256",
        "x": "Ze2loSV3wrroKUN_4zhwGhCqo3Xhu1td4QjeQ5wIVR0",
        "y": "HlLtdXARY_f55A3fnzQbPcm6hgr34Mp8p-nuzQCE0Zw",
        "d": "r_kHyZ-a06rmxM3yESK84r1otSg-aQcVStkRhA-iCM8",
    }
)
recipient = suite_r.create_recipient_context(enc, skr)
pt = recipient.open(ct)

assert pt == b"Hello world!"

API Reference

See Documentation.

Test

You can run tests from the project root after cloning with:

$ tox

Contributing

We welcome all kind of contributions, filing issues, suggesting new features or sending PRs.