// This file was extracted from the TCG Published

// Trusted Platform Module Library

// Part 3: Commands

// Family "2.0"

// Level 00 Revision 01.16

// October 30, 2014

#include "InternalRoutines.h"

#include "Clear_fp.h"

//

//

//     Error Returns                   Meaning

//

//     TPM_RC_DISABLED                 Clear command has been disabled

//

TPM_RC

TPM2_Clear(

   Clear_In          *in                // IN: input parameter list

   )

{

   TPM_RC                  result;

   // Input parameter is not reference in command action

   in = NULL;

   // The command needs NV update. Check if NV is available.

   // A TPM_RC_NV_UNAVAILABLE or TPM_RC_NV_RATE error may be returned at

   // this point

   result = NvIsAvailable();

   if(result != TPM_RC_SUCCESS) return result;

// Input Validation

   // If Clear command is disabled, return an error

   if(gp.disableClear)

       return TPM_RC_DISABLED;

// Internal Data Update

   // Reset storage hierarchy seed from RNG

   gp.SPSeed.t.size = PRIMARY_SEED_SIZE;

   CryptGenerateRandom(PRIMARY_SEED_SIZE, gp.SPSeed.t.buffer);

   // Create new shProof and ehProof value from RNG

   gp.shProof.t.size = PROOF_SIZE;

   CryptGenerateRandom(PROOF_SIZE, gp.shProof.t.buffer);

   gp.ehProof.t.size= PROOF_SIZE;

   CryptGenerateRandom(PROOF_SIZE, gp.ehProof.t.buffer);

   // Enable storage and endorsement hierarchy

   gc.shEnable = gc.ehEnable = TRUE;

   // set the authValue buffers to zero

   MemorySet(gp.ownerAuth.t.buffer, 0, gp.ownerAuth.t.size);

   MemorySet(gp.endorsementAuth.t.buffer, 0, gp.endorsementAuth.t.size);

   MemorySet(gp.lockoutAuth.t.buffer, 0, gp.lockoutAuth.t.size);

   // Set storage, endorsement and lockout authValue to null

   gp.ownerAuth.t.size = gp.endorsementAuth.t.size = gp.lockoutAuth.t.size = 0;

   // Set storage, endorsement, and lockout authPolicy to null

   gp.ownerAlg = gp.endorsementAlg = gp.lockoutAlg = TPM_ALG_NULL;

   gp.ownerPolicy.t.size = 0;

   gp.endorsementPolicy.t.size = 0;

   gp.lockoutPolicy.t.size = 0;

   // Flush loaded object in storage and endorsement hierarchy

   ObjectFlushHierarchy(TPM_RH_OWNER);

   ObjectFlushHierarchy(TPM_RH_ENDORSEMENT);

   // Flush owner and endorsement object and owner index in NV

   NvFlushHierarchy(TPM_RH_OWNER);

   NvFlushHierarchy(TPM_RH_ENDORSEMENT);

   // Save hierarchy changes to NV

   NvWriteReserved(NV_SP_SEED, &gp.SPSeed);

   NvWriteReserved(NV_SH_PROOF, &gp.shProof);

   NvWriteReserved(NV_EH_PROOF, &gp.ehProof);

   NvWriteReserved(NV_OWNER_AUTH, &gp.ownerAuth);

   NvWriteReserved(NV_ENDORSEMENT_AUTH, &gp.endorsementAuth);

   NvWriteReserved(NV_LOCKOUT_AUTH, &gp.lockoutAuth);

   NvWriteReserved(NV_OWNER_ALG, &gp.ownerAlg);

   NvWriteReserved(NV_ENDORSEMENT_ALG, &gp.endorsementAlg);

   NvWriteReserved(NV_LOCKOUT_ALG, &gp.lockoutAlg);

   NvWriteReserved(NV_OWNER_POLICY, &gp.ownerPolicy);

   NvWriteReserved(NV_ENDORSEMENT_POLICY, &gp.endorsementPolicy);

   NvWriteReserved(NV_LOCKOUT_POLICY, &gp.lockoutPolicy);

   // Initialize dictionary attack parameters

   DAPreInstall_Init();

   // Reset clock

   go.clock = 0;

   go.clockSafe = YES;

   // Update the DRBG state whenever writing orderly state to NV

   CryptDrbgGetPutState(GET_STATE);

   NvWriteReserved(NV_ORDERLY_DATA, &go);

   // Reset counters

   gp.resetCount = gr.restartCount = gr.clearCount = 0;

   gp.auditCounter = 0;

   NvWriteReserved(NV_RESET_COUNT, &gp.resetCount);

   NvWriteReserved(NV_AUDIT_COUNTER, &gp.auditCounter);

#ifdef EMBEDDED_MODE

   // Perform any platform-specific actions.

   _plat__OwnerClearCallback();

#endif

   // orderly state should be cleared because of the update to state clear data

   g_clearOrderly = TRUE;

   return TPM_RC_SUCCESS;

}