swarmauri_certs_crlverifyservice 0.1.3

Certificate verification against CRLs

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swarmauri_certs_crlverifyservice

CRL-based certificate verification service for the Swarmauri SDK.

This package implements an ICertService that checks X.509 certificates against Certificate Revocation Lists as described in RFC 5280. It validates the certificate's validity period, issuer, and revocation status.

Features

• CrlVerifyService adapter dedicated to revocation-aware verification and parsing.
• Accepts PEM or DER certificates/CRLs and normalizes them with cryptography.
• Returns structured validity metadata, revocation flags, issuers, and extension details.
• Focuses purely on verification; CSR and signing flows stay delegated to other Swarmauri services.

Prerequisites

• Python 3.10 or newer.
• Access to up-to-date CRLs for the certificate authorities you care about.
• Certificates and CRLs stored in PEM (Base64) or DER; the service can decode either.
• Optional: trusted root/intermediate certificates if you plan to record issuer context alongside revocation checks.

Installation

# pip
pip install swarmauri_certs_crlverifyservice

# poetry
poetry add swarmauri_certs_crlverifyservice

# uv (pyproject-based projects)
uv add swarmauri_certs_crlverifyservice

Quickstart: Revocation Check

Load a certificate and its corresponding CRL, then validate the revocation status and validity window:

import asyncio
from pathlib import Path

from swarmauri_certs_crlverifyservice import CrlVerifyService


async def main() -> None:
    service = CrlVerifyService()

    cert_bytes = Path("leaf.pem").read_bytes()
    crl_bytes = Path("issuer.crl").read_bytes()

    verification = await service.verify_cert(
        cert=cert_bytes,
        crls=[crl_bytes],
        check_revocation=True,
    )

    if verification["valid"]:
        print("Certificate is valid.")
    elif verification.get("revoked"):
        print("Certificate was revoked:", verification["reason"])
    else:
        print("Certificate failed validation:", verification["reason"])


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

Parsing Metadata

Use parse_cert to surface fields needed for logging, auditing, or dashboards:

import asyncio
from pathlib import Path

from swarmauri_certs_crlverifyservice import CrlVerifyService


async def describe() -> None:
    service = CrlVerifyService()
    cert_bytes = Path("leaf.pem").read_bytes()

    metadata = await service.parse_cert(cert_bytes)
    print("Subject:", metadata["subject"])
    print("Valid until:", metadata["not_after"])
    print("Key usage:", metadata.get("key_usage"))


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

Best Practices

• Refresh CRLs frequently; RFC 5280 nextUpdate dictates how long a CRL should be considered valid.
• Combine this service with Swarmauri signing services to perform a full lifecycle check (issue → deploy → monitor).
• Cache CRLs in memory or a fast datastore to avoid repeatedly downloading them when calling verify_cert.
• Log verification outputs (especially reason and revoked) to your observability pipeline to catch trust issues early.