swarmauri_crypto_composite 0.2.0.dev13

Algorithm-routing crypto provider for Swarmauri

---

Swarmauri Crypto Composite

CompositeCrypto is an algorithm-routing crypto provider that delegates encryption operations to the first child provider that advertises support for the requested algorithm. Its behaviour is defined entirely by the wrapped providers:

• Aggregates each provider's supports() capabilities and removes duplicates.
• Normalises requested algorithms before routing so stylistic variants still match.
• Requires at least one child provider to be supplied at construction time.
• Exposes the full asynchronous ICrypto surface area (encrypt, wrap, seal, etc.).

Installation

Choose the tool that best fits your workflow:

pip install swarmauri_crypto_composite

poetry add swarmauri_crypto_composite

uv add swarmauri_crypto_composite

Usage

"""Route crypto operations to the provider that supports the requested algorithm."""
import asyncio

from swarmauri_crypto_composite import CompositeCrypto
from swarmauri_core.crypto.ICrypto import ICrypto
from swarmauri_core.crypto.types import (
    AEADCiphertext,
    ExportPolicy,
    KeyRef,
    KeyType,
    KeyUse,
)


class DummyCrypto(ICrypto):
    def __init__(self, name: str, alg: str) -> None:
        self._name = name
        self._alg = alg

    def supports(self):
        return {"encrypt": (self._alg,)}

    async def encrypt(self, key, pt, *, alg=None, aad=None, nonce=None):
        return AEADCiphertext(
            kid="dummy",
            version=1,
            alg=alg or self._alg,
            nonce=b"",
            ct=self._name.encode(),
            tag=b"",
        )

    async def decrypt(self, key, ct, *, aad=None):  # pragma: no cover - demo only
        raise NotImplementedError

    async def wrap(self, kek, *, dek=None, wrap_alg=None, nonce=None):  # pragma: no cover - demo only
        raise NotImplementedError

    async def unwrap(self, kek, wrapped):  # pragma: no cover - demo only
        raise NotImplementedError

    async def seal(self, recipient, pt, *, alg=None):  # pragma: no cover - demo only
        raise NotImplementedError

    async def unseal(self, recipient_priv, sealed, *, alg=None):  # pragma: no cover - demo only
        raise NotImplementedError


async def main() -> None:
    # Compose two providers that advertise different algorithms.
    chacha = DummyCrypto("chacha", "CHACHA20-POLY1305")
    aes = DummyCrypto("aes", "A256GCM")
    composite = CompositeCrypto([chacha, aes])

    key = KeyRef(
        kid="k",
        version=1,
        type=KeyType.SYMMETRIC,
        uses=(KeyUse.ENCRYPT, KeyUse.DECRYPT),
        export_policy=ExportPolicy.SECRET_WHEN_ALLOWED,
        material=b"\x00" * 32,
    )

    ciphertext = await composite.encrypt(key, b"payload", alg="A256GCM")
    print(f"Selected provider: {ciphertext.ct.decode()}")


if __name__ == "__main__":
    asyncio.run(main())

Entry point

The provider is registered under the swarmauri.cryptos entry-point as CompositeCrypto.

Want to help?

If you want to contribute to swarmauri-sdk, read up on our guidelines for contributing that will help you get started.