Secure Time/Date Virtualization

Abstract

A system is provided that includes a processor and a system memory coupled to the processor, the system memory stores at least one application for execution by the processor. The system also includes logic coupled to the processor, the logic providing a secure time reference. The processor selectively accesses the secure time reference to generate a virtual time reference for the at least one application.

1 . A system, comprising:
 a processor;   a system memory coupled to the processor, the system memory stores at least one application for execution by the processor; and   logic coupled to the processor, the logic providing a secure time reference,   wherein the processor selectively accesses the secure time reference to generate a virtual time reference for the at least one application.   
     
     
         2 . The system of  claim 1  wherein the at least one application comprises a Digital Rights Management (DRM) agent that relies on the virtual time reference to determine when user rights to access a particular file or program of the system expires. 
     
     
         3 . The system of  claim 1  wherein the logic comprises a real-time clock. 
     
     
         4 . The system of  claim 1  wherein the logic comprises an incrementing counter of time units. 
     
     
         5 . The system of  claim 1  wherein the logic provides a validity indicator for the secure time reference. 
     
     
         6 . The system of  claim 5  wherein, if the validity indicator is successfully authenticated, the virtual time reference is updated based on the secure time reference. 
     
     
         7 . The system of  claim 5  wherein, if the validity indicator related to the secure time reference fails authentication, the virtual time reference is reset. 
     
     
         8 . The system of  claim 5  wherein, if the secure time reference is interrupted, the validity indicator is changed using a secure mode of the system. 
     
     
         9 . The system of  claim 5  wherein the validity indicator is automatically changed during a boot process that follows a power loss to the logic. 
     
     
         10 . The system of  claim 1  wherein the processor generates a plurality of independent virtual time references based on the secure time reference. 
     
     
         11 . A method, comprising:
 generating a secure time reference and a validity indicator for the secure time reference; and   if the validity indicator is authenticated, generating a virtual time reference based on the secure time reference.   
     
     
         12 . The method of  claim 11  wherein generating the virtual time reference comprises calculating an offset value between the virtual time reference and the secure time reference. 
     
     
         13 . The method of  claim 11  further comprising resetting the virtual time reference if the validity indicator fails authentication. 
     
     
         14 . The method of  claim 11  further comprising changing the validity indicator if the secure time reference is interrupted. 
     
     
         15 . The method of  claim 14  further comprising changing the validity indicator during a boot process that follows a power loss. 
     
     
         16 . A system, comprising:
 means for generating a secure time reference and a validity indicator for the secure time reference; and   means for generating a plurality of independent virtual time references based on the secure time reference.   
     
     
         17 . The system of  claim 16  further comprising means for authenticating the validity indicator. 
     
     
         18 . The system of  claim 16  further comprising means for detecting an interruption to the secure time reference and for changing the validity indicator due to the interruption. 
     
     
         19 . The system of  claim 16  further comprising means for resetting the independent virtual time references if the validity indicator fails authentication. 
     
     
         20 . The system of  claim 16  further comprising means for securely updating the independent virtual time references.