tlscrlchecker is a Traefik middleware plugin designed to enhance security by verifying the revocation status of client certificates. It uses a Certificate Revocation List (CRL) to ensure that any client certificates that have been revoked cannot access protected services.
- The plugin intercepts requests that use TLS and checks if a client certificate is presented.
- It loads the CRL from the specified file and validates the presented client certificate against the list of revoked certificates.
- If the certificate is revoked, the plugin blocks the request with a 400 Bad Request error. Otherwise, the request is passed to the next middleware or service in the chain.
A sample is provided in the test folder. You can use it to test the plugin in a controlled environment.