Patent ID: 8938072
Filing Date: 2015-01-20
Classification: G06F,H04L

Abstract:
1. A data processing device comprising: a cryptographic accelerator; a key register configured to store keys; a first processor comprising derive key circuitry, said derive key circuitry configured to derive a key responsive to a derive key command and subsequently replace the derive key command with a different command, said first processor further comprising a buffer configured to store at least a first descriptor, the descriptor having a first set of commands, including a derive key command, and data to be processed by the first set of commands wherein said first processor is electronically coupled to said cryptographic accelerator and said key register, and wherein said first processor is configured to receive the first set of commands from said buffer and process the first set of commands, including the derive key command, and wherein said derive key circuitry is configured, responsive to the derive key command processed by said first processor, to cause said cryptographic accelerator to retrieve a first key from a first location in said key register and alter the first key to create a derived key from said first key, and wherein said derive key circuitry is further configured to place the derived key in a location in the key register, and subsequent to the creation of the derived key, replace the derive key command in the first set of commands in the first descriptor in said buffer with a second command other than a derive key command.