Method and system for preventing reset of a cryptographic subsystem when entering or recovering from a powered-off sleep state

A method for preventing an unauthorized reset of a cryptographic subsystem in a personal computer system (system), the method comprising the steps of:

• a) receiving notification that the system is entering a powered off sleep state;
• b) setting a block signal for blocking a cryptographic subsystem reset;
• and
• c) locking the block signal, such that the cryptographic subsystem is protected from intrusion while in and recovering from the powered off sleep state.

A method for preventing reset of a cryptographic subsystem in a personal computer system when in and recovering from a powered off sleep state, the method comprising the steps of:

• a) setting a block signal when a powered off sleep state is being entered for blocking a cryptographic subsystem reset;
• b) setting a lock signal for locking the block signal such that the cryptographic subsystem is protected from intrusion while in the powered off sleep state;
• c) asserting a system reset when the PC system begins recovering from the powered off sleep state, wherein the system reset releases the lock signal;
• and
• d) clearing the block signal such that the at least one device driver regains control of the cryptographic subsystem reset.

A blocking circuit for preventing a cryptographic subsystem reset when in or recovering from a powered off sleep state, the cryptographic subsystem including at least one device driver, the blocking circuit comprising:

• means for setting a block signal when entering the powered off sleep state;
• a first latch for receiving the block signal, the first latch being coupled to the cryptographic subsystem reset;
• means for setting a lock signal after the block signal has been set;
• and
• a second latch for receiving the lock signal and the block signal, wherein the block signal and the lock signal set the second latch and hold the block signal in the first latch such that the cryptographic subsystem reset is blocked.