sdkey 0.1.1

Official Python client for the SDKey license authentication protocol

sdkey

Official Python client for SDKey license authentication.

Implements the sealed session protocol: Ed25519-verified handshake, HKDF session keys, and AES-256-GCM validate envelopes. See PROTOCOL.md.

Install

pip install sdkey

Requires Python 3.10+.

Quick start

Embed these values from the SDKey dashboard when you ship your app:

from sdkey import SdkeyClient, SdkeyError

client = SdkeyClient(
    api_base_url="https://api.sdkey.dev",
    app_id="YOUR_APP_ID",
    app_public_key_b64="YOUR_APP_PUBLIC_KEY_BASE64",
)

try:
    result = client.validate("SDKY-XXXX-XXXX-XXXX-XXXX", "machine-hwid")
    if result.success:
        print("licensed", result.status, result.expires_at)
    else:
        print("denied", result.code, result.message)
except SdkeyError as err:
    print(err.code, err.message)
    raise

validate calls init() automatically when no session exists. Sessions last ~15 minutes server-side; on SESSION_EXPIRED the client clears local state so the next call re-handshakes.

API

SdkeyClient(options)

Option	Type	Description
api_base_url	str	API origin (no trailing slash)
app_id	str	Application UUID
app_public_key_b64	str	Raw Ed25519 public key (32 bytes), base64
http_post	callable	Optional HTTP POST override (tests / custom transport)

Methods

• init() — challenge handshake; verifies the signed hello; derives the AES session key
• validate(license_key, hwid) — sealed validate; always decrypts then verifies the Ed25519 signature before trusting success
• get_session() / clear_session() — inspect or drop the local session

Errors

Protocol / transport failures raise SdkeyError with a code:

INIT_FAILED · HELLO_SIGNATURE_INVALID · VALIDATE_RESPONSE_INVALID · RESPONSE_SIGNATURE_INVALID · SESSION_MISMATCH · CLOCK_SKEW · NETWORK

License denials (banned, HWID mismatch, etc.) return a normal ValidateResult with success=False — they are not raised.

Security notes

• Never ship app private keys in a client.
• Do not skip signature verification — that is the anti-spoof binding.
• This package is open source; the SDKey server remains a separate product.

Development

python -m pip install -e ".[dev]"
pytest

License

MIT