Patent ID: 7290284
Filing Date: 2007-10-30
Classification: G06F

Abstract:
1. System for data processing a security critical activity in a secure management mode in a computer, the system comprising: a computer comprising a computer processor, a computer bus, a bridge, a main memory, and a plurality of handling devices connecting to the computer processor via the bridge, the main memory being one of the plural handling devices; a security device comprising a security device processor with a protection mode signal generator (SGpm) and an alter signal generator (SGa), the security device processor connected to the bridge; a switch connected between the bridge and each handling device, the switch containing a table of addresses to different ones of the handling devices including parts of the handling devices, and a comparator, the table having accessibility allocations specifying handling devices or the parts thereof allocated only to the security device and allocated to the computer processor operating in a normal mode, the table of the switch being changeable only under control of signals generated by the security device; and an alter signal receiver (SRa), a source signal receiver (SRs), and a protection mode signal receiver (SRpm) connected to the switch, wherein, the switch is connected to address lines and to operation lines of the bus, the switch is configured for i) a first normal mode wherein the computer processor has access to a first group of the handling devices, and ii) a second protected mode wherein the computer processor is denied access to the first group of handling devices and the security processor is allowed access to the first group of handling devices and to execute a security critical activity with the first group of handling devices, said signals from the security device, enabling the security device and the security processor access to the handling devices and denying the computer processor access to the handling devices, changes the switch from the first normal mode into the second protection mode, and the computer processor and the security device processor are separate processors.