Static CRL certificate validation

Overview

A Certificate Authority (CA) may wish to publish a Certificate Revocation List (CRL) to a file. In this case, API Gateway can load the revoked certificates from the file-based CRL and validate user certificates against it.

[Note] Note
Because the CRL is typically signed by the CA that owns it, the CA certificate that issued the CRL must first be imported into the certificate store. In addition, the CRL (Static) filter requires the certificates message attribute to be set by a preceding filter.

Example CRL-based validation policy

Typically, a Find Certificate filter is first used to find the certificate, which is stored in a certificate message attribute. You can then use a Copy / Modify Attributes filter to copy the certificate attribute to the certificates attribute by selecting its Create list attribute setting.

The following example policy shows the filters used:

Static CRL Policy

The following example shows the settings used in the Copy / Modify Attributes filter:

Copy / Modify Attributes Filter

[Important] Important
Typically, a CA publishes a new CRL, containing the most up-to-date list of revoked certificates at regular intervals. However, the CRL (Static) filter does not automatically update the CRL when it is loaded from a local file. If you need to automatically retrieve updated CRLs from a particular URL, you should use the CRL (Dynamic) filter instead. For more details, see Dynamic CRL certificate validation.

Configuration

Enter a name for the filter in the Name field, and click the Load CRL button to browse to the location of the CRL file. When the CRL has been loaded from the selected location, read-only information regarding revoked certificates and update dates is displayed in the other fields on the window.