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 "HMAC_Start_fp.h" 10 // 11 // 12 // Error Returns Meaning 13 // 14 // TPM_RC_ATTRIBUTES key referenced by handle is not a signing key or is restricted 15 // TPM_RC_OBJECT_MEMORY no space to create an internal object 16 // TPM_RC_KEY key referenced by handle is not an HMAC key 17 // TPM_RC_VALUE hashAlg is not compatible with the hash algorithm of the scheme of 18 // the object referenced by handle 19 // 20 TPM_RC 21 TPM2_HMAC_Start( 22 HMAC_Start_In *in, // IN: input parameter list 23 HMAC_Start_Out *out // OUT: output parameter list 24 ) 25 { 26 OBJECT *hmacObject; 27 TPMT_PUBLIC *publicArea; 28 TPM_ALG_ID hashAlg; 29 30 // Input Validation 31 32 // Get HMAC key object and public area pointers 33 hmacObject = ObjectGet(in->handle); 34 publicArea = &hmacObject->publicArea; 35 36 // Make sure that the key is an HMAC key 37 if(publicArea->type != TPM_ALG_KEYEDHASH) 38 return TPM_RC_TYPE + RC_HMAC_Start_handle; 39 40 // and that it is unrestricted 41 if(publicArea->objectAttributes.restricted == SET) 42 return TPM_RC_ATTRIBUTES + RC_HMAC_Start_handle; 43 44 // and that it is a signing key 45 if(publicArea->objectAttributes.sign != SET) 46 return TPM_RC_KEY + RC_HMAC_Start_handle; 47 48 // See if the key has a default 49 if(publicArea->parameters.keyedHashDetail.scheme.scheme == TPM_ALG_NULL) 50 // it doesn't so use the input value 51 hashAlg = in->hashAlg; 52 else 53 { 54 // key has a default so use it 55 hashAlg 56 = publicArea->parameters.keyedHashDetail.scheme.details.hmac.hashAlg; 57 // and verify that the input was either the TPM_ALG_NULL or the default 58 if(in->hashAlg != TPM_ALG_NULL && in->hashAlg != hashAlg) 59 hashAlg = TPM_ALG_NULL; 60 } 61 // if we ended up without a hash algorith then return an error 62 if(hashAlg == TPM_ALG_NULL) 63 return TPM_RC_VALUE + RC_HMAC_Start_hashAlg; 64 65 // Internal Data Update 66 67 // Create a HMAC sequence object. A TPM_RC_OBJECT_MEMORY error may be 68 // returned at this point 69 return ObjectCreateHMACSequence(hashAlg, 70 in->handle, 71 &in->auth, 72 &out->sequenceHandle); 73 } 74
