public void CalculateDigests(GetPCRValueDelegate getPCRValue)
{
List <byte[]> pcrValues = new List <byte[]>();
for (uint i = 0; i < _pcrSelection.PcrSelection.BitCount; i++)
{
if (_pcrSelection.PcrSelection.GetBit((int)i))
{
pcrValues.Add(getPCRValue(i));
}
}
TPMPCRCompositeCore composite = new TPMPCRCompositeCore();
composite.PCRSelection = _pcrSelection;
composite.PCRValues = pcrValues.ToArray();
_digest = new HashProvider().Hash(new HashTPMBlobWritableDataProvider(composite));
}
protected override TPMCommandResponse InternalProcess()
{
TPMBlob requestBlob = new TPMBlob();
requestBlob.WriteCmdHeader(TPMCmdTags.TPM_TAG_RQU_AUTH1_COMMAND, TPMOrdinals.TPM_ORD_Quote);
//key handle gets inserted later, it may be not available now
requestBlob.WriteUInt32(0);
requestBlob.Write(_nonce, 0, 20);
_pcrSelection.WriteToTpmBlob(requestBlob);
_keyManager.LoadKey(_params.GetValueOf <string>("key"));
AuthorizeMe(requestBlob);
using (_keyManager.AcquireLock())
{
requestBlob.SkipHeader();
requestBlob.WriteUInt32(_keyManager.IdentifierToHandle(_params.GetValueOf <string>("key")).Handle);
_responseBlob = TransmitMe(requestBlob);
}
CheckResponseAuthInfo();
_responseBlob.SkipHeader();
TPMPCRCompositeCore pcrComposite = TPMPCRCompositeCore.CreateFromTPMBlob(_responseBlob);
uint sigSize = _responseBlob.ReadUInt32();
byte[] signature = _responseBlob.ReadBytes((int)sigSize);
// Do signature verification
TPMQuoteInfoCore quoteInfo = TPMQuoteInfoCore.Create(new HashProvider().Hash(new HashTPMBlobWritableDataProvider(pcrComposite)), _nonce);
byte[] signingData;
using (TPMBlob blob = new TPMBlob())
{
quoteInfo.WriteToTpmBlob(blob);
signingData = blob.ToArray();
}
Parameters pubKeyParams = new Parameters();
pubKeyParams.AddPrimitiveType("key", _params.GetValueOf <string>("key"));
TPMCommandRequest pubKeyRequest = new TPMCommandRequest(TPMCommandNames.TPM_CMD_GetPubKey, pubKeyParams);
TPMCommandResponse pubKeyResponse = _tpmWrapper.Process(pubKeyRequest,
_commandAuthHelper, _keyManager);
if (pubKeyResponse.Status == false)
{
_log.FatalFormat("TPM_Quote: Could not retrieve pubkey of key");
return(new TPMCommandResponse(false, TPMCommandNames.TPM_CMD_Quote, new Parameters()));
}
TPMKey keyInfo = TPMKeyCore.CreateFromBytes(_keyManager.GetKeyBlob(_params.GetValueOf <string>("key")));
TPMPubkey pubkey = pubKeyResponse.Parameters.GetValueOf <TPMPubkey>("pubkey");
if (SignatureVerification.VerifySignature(keyInfo, pubkey, signingData, signature) == false)
{
throw new ArgumentException("The TPM_Quote signature could not be verified");
}
Parameters responseParams = new Parameters();
responseParams.AddValue("pcrData", pcrComposite);
responseParams.AddPrimitiveType("sig", signature);
return(new TPMCommandResponse(true, TPMCommandNames.TPM_CMD_Quote, responseParams));
}
