A CIRCUIT CHIP FOR CRYPTOGRAPHIC PROCESSING HAVING A SECURE INTERFACE TO AN EXTERNAL MEMORY

摘要

A mechanism is provided in which a secure chip for performing cryptographic and/or other functions is able to securely access a separate random access memory externally disposed with respect to a secure chip boundary. Addressing of the external memory is controlled so as to define certain regions therein which receive and store only encrypted information from the chip. Other regions of the external memory are set aside for the receipt and storage of unencrypted information. Access to the external memory is provided through a controlled interface which communicates with internal chip hardware which operates to control the flow of communication between various internal components such as cryptographic engines, data processors, internal memory of both the volatile and the nonvolatile variety and an external interface which provides the only other access to the chip. The internal chip hardware with which the external memory interface communicates is implemented as a combined ASIC and programmable hardware circuit, wherein the programmable hardware circuit is also securely configurable.