pysui-crypto
June 18, 2026 ยท View on GitHub
A Python extension providing zkLogin <https://docs.sui.io/concepts/cryptography/zklogin>_ and
SEAL <https://github.com/MystenLabs/seal>_ threshold encryption support for Sui <https://sui.io>,
extending the pysui <https://github.com/FrankC01/pysui> SDK.
The library is backed by a Rust crate compiled via PyO3 <https://pyo3.rs>_ and
maturin <https://www.maturin.rs>_, exposing a native Python extension module.
Requirements
- Python 3.10 or later
pysui <https://github.com/FrankC01/pysui>_ โ integrated in the upcoming pysui 1.1.0 release (date TBD)
Installation
From PyPI (sdist)
Only a source distribution is published to PyPI. Installing it requires a Rust toolchain and
`maturin <https://www.maturin.rs>`_:
.. code-block:: bash
pip install maturin
pip install pysui-crypto
Pre-built wheels
~~~~~~~~~~~~~~~~
Platform wheels for Linux (x86_64, aarch64), Windows (x64), and macOS (x86_64, aarch64) are
attached to each `GitHub release <https://github.com/Suitters/pysui-crypto/releases>`_ as zip
archives. Download the archive for your platform and install the wheel directly:
.. code-block:: bash
pip install pysui_crypto-<version>-<platform>.whl
Build from source
maturin <https://www.maturin.rs>_ is required to compile the Rust extension:
.. code-block:: bash
pip install maturin
maturin develop # installs into the active virtual environment
To produce a wheel:
.. code-block:: bash
maturin build --release --out dist
zkLogin Support
Functions for constructing and submitting zkLogin <https://docs.sui.io/concepts/cryptography/zklogin>_
authenticated transactions on Sui.
generate_ephemeral_keypair(as_secp256r1)
Generate an Ed25519 (default) or secp256r1 ephemeral key pair for nonce construction.
Returns {"public_key": bytes, "private_key": bytes}.
extract_jwt_claims(jwt)
Parse a zkLogin JWT and enforce Sui size constraints.
Returns (iss, sub, aud, nonce).
compute_nonce(epk_bytes, max_epoch, randomness)
Compute the Poseidon-hashed nonce to embed in the OAuth authorization request.
compute_address_seed(key_claim_name, key_claim_value, audience, user_salt)
Compute the 32-byte BN254/Poseidon address seed from JWT claims and a user salt.
compute_zklogin_address(iss, address_seed, legacy)
Derive the final Blake2b256 Sui address from the issuer string and address seed.
build_zklogin_signature(proof_json, ephemeral_sig, address_seed, max_epoch)
Assemble and BCS-serialize a ZkLoginAuthenticator; returns standard base64
ready for the Sui RPC.
SEAL Support
Functions for SEAL <https://github.com/MystenLabs/seal>_ threshold encryption.
SEAL requires access to one or more running SEAL key servers; this library provides
the client-side cryptographic primitives only.
DemType
Enum of supported data-encapsulation mechanisms: AesGcm256, Hmac256Ctr, Plain.
EncryptedObject
Parse and inspect a SEAL encrypted object (parse(data) / to_bytes()).
Exposes version, package_id, id, threshold, services, dem_type.
seal_encrypt(package_id, id, key_servers, public_keys, threshold, data, dem_type, aad)
Threshold-encrypt plaintext using IBE. Returns (ciphertext, dem_key)
where dem_key is non-None only for Plain mode.
seal_decrypt(encrypted_object, user_secret_keys, public_keys)
Decrypt a SEAL ciphertext using user secret keys collected from key servers.
generate_session_keypair()
Generate an Ed25519 session key pair for SEAL key server authentication.
Returns {"public_key": bytes, "private_key": bytes}.
generate_elgamal_keypair()
Generate an ElGamal key pair for SEAL key server encryption.
Returns {"public_key": bytes, "private_key": bytes}.
elgamal_decrypt(sk, encryption)
Decrypt an ElGamal ciphertext using a private key.
verify_user_secret_key(usk, full_id, public_key)
Verify a user secret key returned by a key server; raises ValueError on failure.
seal_signed_message(package_id, session_vk, creation_time, ttl_min)
Construct the key server request message for signing; returns hex-encoded bytes.
License
Apache-2.0