1// This file was extracted from the TCG Published
2// Trusted Platform Module Library
3// Part 3: Commands
4// Family "2.0"
5// Level 00 Revision 01.16
6// October 30, 2014
7
8#include "InternalRoutines.h"
9#include "PolicyNameHash_fp.h"
10//
11//
12//     Error Returns                     Meaning
13//
14//     TPM_RC_CPHASH                     nameHash has been previously set to a different value
15//     TPM_RC_SIZE                       nameHash is not the size of the digest produced by the hash
16//                                       algorithm associated with policySession
17//
18TPM_RC
19TPM2_PolicyNameHash(
20   PolicyNameHash_In     *in                  // IN: input parameter list
21   )
22{
23   SESSION               *session;
24   TPM_CC                 commandCode = TPM_CC_PolicyNameHash;
25   HASH_STATE             hashState;
26
27// Input Validation
28
29   // Get pointer to the session structure
30   session = SessionGet(in->policySession);
31
32   // A new nameHash is given in input parameter, but cpHash in session context
33   // is not empty
34   if(in->nameHash.t.size != 0 && session->u1.cpHash.t.size != 0)
35       return TPM_RC_CPHASH;
36
37   // A valid nameHash must have the same size as session hash digest
38   if(in->nameHash.t.size != CryptGetHashDigestSize(session->authHashAlg))
39       return TPM_RC_SIZE + RC_PolicyNameHash_nameHash;
40
41// Internal Data Update
42
43   // Update policy hash
44   // policyDigestnew = hash(policyDigestold || TPM_CC_PolicyNameHash || nameHash)
45   // Start hash
46   CryptStartHash(session->authHashAlg, &hashState);
47
48   // add old digest
49   CryptUpdateDigest2B(&hashState, &session->u2.policyDigest.b);
50
51   // add commandCode
52   CryptUpdateDigestInt(&hashState, sizeof(TPM_CC), &commandCode);
53
54   // add nameHash
55   CryptUpdateDigest2B(&hashState, &in->nameHash.b);
56
57   // complete the digest
58   CryptCompleteHash2B(&hashState, &session->u2.policyDigest.b);
59
60   // clear iscpHashDefined bit to indicate now this field contains a nameHash
61   session->attributes.iscpHashDefined = CLEAR;
62
63   // update nameHash in session context
64   session->u1.cpHash = in->nameHash;
65
66   return TPM_RC_SUCCESS;
67}
68