| 摘要 |
Data is retrieved from a data memory by transmitting instructions containing the memory address of the data to be retrieved. A privileged data table stores a list identifying those regions of the data memory that store privileged or sensitive data. A privileged rule enforcer determines whether an instruction is attempting to access privileged data by comparing the address contained in the instruction with the regions of memory identified by the privileged data table as storing privileged data. If the instruction is attempting to access privileged data, the privileged rule enforcer blocks the instruction, and therefore the data access, unless the instruction is identified as having been verified by a code verifier and the data access satisfies one or more data access rules. To determine whether an instruction has been verified, the privilege rule enforcer receives a privilege signal which is asserted when a verified instruction is transmitted. The data access rules are defined by a rule signal received by the privileged rule enforcer. |
