| // 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 "PolicyPCR_fp.h" |
| // |
| // |
| // Error Returns Meaning |
| // |
| // TPM_RC_VALUE if provided, pcrDigest does not match the current PCR settings |
| // TPM_RC_PCR_CHANGED a previous TPM2_PolicyPCR() set pcrCounter and it has changed |
| // |
| TPM_RC |
| TPM2_PolicyPCR( |
| PolicyPCR_In *in // IN: input parameter list |
| ) |
| { |
| SESSION *session; |
| TPM2B_DIGEST pcrDigest; |
| BYTE pcrs[sizeof(TPML_PCR_SELECTION)]; |
| UINT32 pcrSize; |
| BYTE *buffer; |
| INT32 bufferSize; |
| TPM_CC commandCode = TPM_CC_PolicyPCR; |
| HASH_STATE hashState; |
| |
| // Input Validation |
| |
| // Get pointer to the session structure |
| session = SessionGet(in->policySession); |
| |
| // Do validation for non trial session |
| if(session->attributes.isTrialPolicy == CLEAR) |
| { |
| // Make sure that this is not going to invalidate a previous PCR check |
| if(session->pcrCounter != 0 && session->pcrCounter != gr.pcrCounter) |
| return TPM_RC_PCR_CHANGED; |
| |
| // Compute current PCR digest |
| PCRComputeCurrentDigest(session->authHashAlg, &in->pcrs, &pcrDigest); |
| |
| // If the caller specified the PCR digest and it does not |
| // match the current PCR settings, return an error.. |
| if(in->pcrDigest.t.size != 0) |
| { |
| if(!Memory2BEqual(&in->pcrDigest.b, &pcrDigest.b)) |
| return TPM_RC_VALUE + RC_PolicyPCR_pcrDigest; |
| } |
| } |
| else |
| { |
| // For trial session, just use the input PCR digest |
| pcrDigest = in->pcrDigest; |
| } |
| // Internal Data Update |
| |
| // Update policy hash |
| // policyDigestnew = hash( policyDigestold || TPM_CC_PolicyPCR |
| // || pcrs || pcrDigest) |
| // Start hash |
| CryptStartHash(session->authHashAlg, &hashState); |
| |
| // add old digest |
| CryptUpdateDigest2B(&hashState, &session->u2.policyDigest.b); |
| |
| // add commandCode |
| CryptUpdateDigestInt(&hashState, sizeof(TPM_CC), &commandCode); |
| |
| // add PCRS |
| buffer = pcrs; |
| bufferSize = sizeof(TPML_PCR_SELECTION); |
| pcrSize = TPML_PCR_SELECTION_Marshal(&in->pcrs, &buffer, &bufferSize); |
| CryptUpdateDigest(&hashState, pcrSize, pcrs); |
| |
| // add PCR digest |
| CryptUpdateDigest2B(&hashState, &pcrDigest.b); |
| |
| // complete the hash and get the results |
| CryptCompleteHash2B(&hashState, &session->u2.policyDigest.b); |
| |
| // update pcrCounter in session context for non trial session |
| if(session->attributes.isTrialPolicy == CLEAR) |
| { |
| session->pcrCounter = gr.pcrCounter; |
| } |
| |
| return TPM_RC_SUCCESS; |
| } |