A computing device implements a key management system (KMS), and includes an interface, memory, and processing circuitry that executes operational instructions to maintain structured key parameters and a generating procedure associated with associated with a structured key. The generating procedure produces the structured key from an Oblivious Pseudorandom Function (OPRF) output, and the structured key parameters. The computing device receives a blinded value associated with the structured key from a requesting computing device, processes the blinded value using an OPRF secret to generate a blinded OPRF output, and returns the blinded OPRF output, the generating procedure, and the structured key parameters to the requesting computing device, which uses that information to generate the requested structured key.