Transition between states in a processor
View Patent ↗In one implementation, a processor is provided that includes logic to enable a transition from a zeroize state to a clear state. In another implementation, a processor is provided that includes logic to enable a testing secure state, the testing state to enable a testing function; logic to enable a clear state, the clear state to enable a non-secure processing function and to disable a security function; logic to enable a transition from a testing secure state to a clear state; and logic to enable a full secure state, the full secure state to enable the processing function. In another implementation, a processor is provided that includes logic to disable a transition from a clear state to a secure state.
1. An apparatus, comprising:
a processor that
enables a clear state, the clear state to enable a non-secure processing function and to disable a security function;
enables a secure state that comprises a temporary secure state and a non-volatile secure state, the secure state to enable a secure processing function;
enables a transition from the temporary secure state to the clear state, wherein the transition to the clear state from the temporary secure state is enabled based on a reset pulse; and
enables a transition from the non-volatile secure state to the clear state, wherein the transition to the clear state from the non-volatile secure state is enabled based on a power loss.
2. The apparatus of claim 1 , the processor that:
enables a zeroize state, the zeroize state being a security disabled fault state; and
transitions from the zeroize state to the clear state.
3. The apparatus of claim 2 , wherein the zeroize state enables at least one key in a memory coupled to the processor be erased.
4. The apparatus of claim 2 , the processor that:
enables a transition (i) from the secure state to the zeroize state or (ii) from the clear state to the secure state.
5. The apparatus of claim 2 , wherein the secure state further comprises a full secure state, the processor that:
enables a transition from the full secure state to the zeroize state, wherein the transition to the zeroize state from the full secure state is enabled based on a security violation.
6. A method comprising:
enabling a clear state in which a processor operates, the clear state to enable a non-secure processing function and to disable a security function;
enabling a secure state in which the processor operates, the secure state comprising a temporary secure state and a non-volatile secure state, the secure state to enable a secure processing function;
enabling a transition from the temporary secure state to the clear state, wherein the transition to the clear state from the temporary secure state is enabled based on a reset pulse; and
enabling a transition from the non-volatile secure state to the clear state, wherein the transition to the clear state from the non-volatile secure state is enabled based on a power loss.
7. The method of claim 6 , wherein the secure state further comprises a full secure state.
8. The method of claim 7 , further comprising:
enabling a transition from the clear state to the temporary secure state or the non-volatile secure state;
enabling a transition from the temporary secure state or the non-volatile secure state to the clear state; and
enabling a transition from the clear state to the full secure state.
9. The method of claim 7 , further comprising:
enabling a zeroize state, the zeroize state being a security disabled fault state;
enabling a transition from the full secure state to the zeroize state.
10. The method of claim 7 , further comprising:
enabling a transition from the temporary secure state or the non-volatile secure state to the full secure state.
11. The method of claim 7 , further comprising:
enabling a transition from the clear state to the full secure state.
12. The method of claim 9 , wherein the transition to the zeroize state from the full secure state is enabled based on a security violation.
13. An apparatus, comprising:
a processor comprising a state machine that:
enables a clear state, the clear state to enable a non-secure processing function;
enables a secure state comprising a temporary secure state and a non-volatile secure state, the secure state to enable a secure processing function, wherein:
a transition from the temporary secure state to the clear state is enabled based on a reset pulse, and
a transition from the non-volatile secure state to the clear state is enabled based on a power loss.
14. The apparatus of claim 13 , the state machine that:
disables a transition from the clear state to the secure state; and
enables the disabled transition from the clear state to the secure state.
15. The apparatus of claim 13 , wherein the secure state further comprises a full secure state that is transitioned to a zeroize state based on a security violation.