1. An apparatus for performing cryptographic operations, comprising: a cryptographic instruction, received by a computing device as part of an instruction flow executing on said computing device, wherein said cryptographic instruction prescribes one of the cryptographic operations, and wherein said cryptographic instruction prescribes that a user-generated key schedule be employed for execution of said one of the cryptographic operations; keygen logic, operatively coupled to said cryptographic instruction, configured to direct said computing device to load said user-generated key schedule; and execution logic, operatively coupled to said keygen logic, configured to employ said user-generated key schedule to execute said one of the cryptographic operations.