A method and system for secure and scalable key management for cryptographic processing of data is described herein. In the method, a General Purpose Cryptographic Engine (GPE) receives key material via a secure channel from a key server and stores the received Key encryption keys (KEKs) and/or plain text keys in a secure key cache. When a request is received from a host to cryptographically process a block of data, the requesting entity is authenticated using an authentication tag included in the request. The GPE retrieves a plaintext key or generate a plaintext using a KEK if the authentication is successful, cryptographically processes the data using the plaintext key and transmits the processed data. The system includes a key server that securely provides encrypted keys and/or key handles to a host and key encryption keys and/or plaintext keys to the GPE.