Unreachable OCSR
With OCSP enabled, the client implementation running on the Oracle® Enterprise Session Border Controller supports message exchange between the Oracle® Enterprise Session Border Controller and an OCSR as specified in RFC 2560, X.509 Internet Public Key Infrastructure Online Certificate Status Protocol - OCSP. The Oracle® Enterprise Session Border Controller contacts the OCSR whenever a remote client attempts to establish an SSL/TLS connection with the Oracle® Enterprise Session Border Controller. The Oracle® Enterprise Session Border Controller sends a request to the OCSR to check the current status of the certificate presented by the remote client. The Oracle® Enterprise Session Border Controller suspends processing of the SSL/TLS connection request pending receipt of the OCSR response. In previous releases (prior to Version S-CX6.3.0), a good OCSR response resulted in the establishment of a secure SSL/TLS connection. A revoked or unknown OCSR response, or the failure to reach an OCSR, resulted in the rejection of the connection attempt.
This behavior, which adheres to the requirements of RFC 2560, conflicts with the requirements of Section 5.4.6.2.1.6.4.a.i of UCR 2008 which requires an OCSP client to attempt authentication of remote clients in the event of an unreachable OCSR.
Release S-CX6.3F1 adds a new attribute (ignore-dead-responder) to the TLS profile configuration element to provide compliance with DISA/DoD requirements specifying OCSP client operations when faced with unreachable OCSRs. By default, the attribute is disabled meaning that all client connections will be disallowed in the event of unreachable OCSRs.
In DISA/DoD environments ignore-dead-responder should be enabled, allowing local certificate-based authentication by the Oracle® Enterprise Session Border Controller in the event of unreachable OCSRs. Successful authentication is achieved if the certificate presented by the remote client was signed by a Certificate Authority (CA) referenced by the trusted-ca-certificates attribute. If the local authentication succeeds, the secure TLS/SSL connection is established; otherwise the connection is rejected.