NAME
   CSSM_SetPrivilege - Store privilege value in CSSM framework (CDSA)

 SYNOPSIS
   # include <cssm.h>

        CSSM_RETURN CSSMAPI CSSM_SetPrivilege
        (CSSM_PRIVILEGE Privilege)

 LIBRARY
   Common Security Services Manager library (CDSA$INCSSM300_SHR.EXE)

 PARAMETERS
   Privilege (input)
           The CSSM_PRIVILEGE value to be applied to subsequent calls
           to CSSM interfaces.

 DESCRIPTION
   The CSSM_SetPrivilege() function accepts as input a privilege value
   and stores it in the CSSM framework. The integrity credentials of the
   module calling CSSM_SetPrivilege() must be verified by CSSM before the
   privilege value is updated. Integrity credentials are established
   using CSSM_Introduce(). CSSM will perform a pointer validation check
   to ensure the caller has been previously introduced.  The
   CSSM_SetPrivilege() function will fail if no integrity information can
   be found for the caller.

   After pointer validation checks, CSSM verifies the requested privilege
   is authorized. This is done by comparing Privilege with the set of
   privileges contained in the caller manifest. If Privilege is not a
   member, the CSSM_SetPrivilege() call fails.

   Subsequent calls to the framework that require privileges inherit the
   privilege value previously established by CSSM_SetPrivilege().  CSSM
   will perform pointer validation checks on the API caller before
   servicing the API call. If OK, then the Privilege value is supplied to
   the SPI function.

   Internally, CSSM builds and maintains privilege information based on the
   chosen scope of the implementation. The scope may be dictated by the
   capabilities of the platform hosting the CSSM. If threading is
   available, the privilege value can be associated with the thread ID of
   the currently executing thread.  In this scenario, CSSM can manage a
   table of tuples consisting of threadID and privilege value. If
   threading is not available, the privilege value can be global to the
   process.

   Because the selected privilege value is shared, the application
   programmer should take precautions to reset the privilege value
   whenever program flow leaves the caller's module and again when
   control flow returns. In general, any time there is a possibility
   for CSSM_SetPrivilege() to be called while within the context of
   the security critical section, CSSM_SetPrivilege() should be called
   again. Otherwise, the module receiving execution control could have
   called CSSM_SetPrivilege(), resulting in the privilege value being
   reset.

   Data structures used to maintain the global privilege value should
   be initialized in CSSM_Init(). This includes lock initialization and
   preliminary resource allocation. The CSSM_Init() function is assumed
   to be idempotent with respect to shared structure initialization.
   This means CSSM_Init() will ensure a single thread initializes the
   shared structure and subsequent calls to CSSM_Init() will not
   reinitialize it. A reference count of calls to CSSM_Init() is needed
   to ensure matching calls to CSSM_Terminate() are handled.

   Resource cleanup is performed at CSSM_Terminate() after the reference
   count falls to zero. The last call to CSSM_Terminate() results in
   shared resources being freed and lock structures being released.

 ERRORS
   Errors are described in the CDSA technical standard.  See CDSA.

 SEE ALSO
   Books

   Intel CDSA Application Developer's Guide (see CDSA)

   Other Help Topics