A cryptographic device protocol provides a generic interface allowing pre-OS applications to employ any of a variety of cryptographic devices within the pre-OS environment. The generic interface can be used independent of the specific cryptographic devices and is independent of the cryptographic or hashing algorithms used by each device. Cryptographic functions may be performed in the pre-OS environment by pre-OS applications communicating with cryptographic device drivers using the cryptographic device protocol that is independent of the cryptographic devices. Each cryptographic device may be identified by a unique device identifier and may have a number of keys available to it, with each key being identified by a unique key identifier.