Methods and systems for achieving high assurance computing using low assurance operating systems and processes
A computing system contains and uses a partitioning microkernel (PMK) or equivalent means for imposing memory partitioning and isolation prior to exposing data to a target operating system or process, and conducts continuing memory management whereby data is validated by security checks before or between sequential processing steps. The PMK may be used in conjunction with an Object Request Broker.
1. A method for operating a multi processor system with shared memory and at least one hardware memory management unit, comprising the steps of:
booting a first memory partitioning kernel in one processor;
seizing control of said at least one hardware memory management unit by said memory partitioning kernel;
partitioning available memory so as to allocate and isolate a specific region of memory for each respective processor;
booting processes in said processors; and
limiting memory access by each said processor to its respective said specific region of memory.
2. The method of claim 1 , said multi processor system comprising one from among a group consisting of an FPGA, DSP, GPP, ASIC, motherboard chipset, and PCI Device.
3. The method of claim 1 , further comprising:
limiting data access by at least one said region of memory to another said region of memory to read-only.
4. The method of claim 1 , said partitioning available memory comprising partitioning available memory for processes to run within a processor.
5. The method of claim 1 , further comprising:
limiting by the hardware memory management unit, of memory access and sub-Partitioning of respective specific regions of memory by other programs, to within specified ranges of memory.
6. The method of claim 1 , further comprising:
limiting subsequent changes to said memory isolation partitions to said first memory partitioning kernel.
7. The method of claim 1 , further comprising:
limiting memory access by processors to their respective specific regions of memory defined by said first memory partitioning kernel.
8. The method of claim 1 , wherein a said process in said processors comprises a respective process-specific memory partitioning kernel, said method further comprising the steps of:
booting said process-specific memory partitioning kernel and therewith
seizing control of a respective process-specific hardware memory management unit by said process-specific memory partitioning kernel;
sub-partitioning the respective said specific region of available memory so as to allocate and isolate a process-specific subregion of memory for each processor process; booting a process in said processor; and
limiting memory access by said process to its respective said process-specific subregion of memory.