/// <summary>
/// Get an ECDH key exchange key (one pass ephemeral) and the public key of
/// the ephemeral key using ECDH with encodingParms as input to the KDF (ECC only).
/// </summary>
/// <param name="encodingParms"></param>
/// <param name="pubEphem"></param>
/// <returns></returns>
public byte[] EcdhGetKeyExchangeKey(byte[] encodingParms, out EccPoint ephemPubPt)
{
using (AsymCryptoSystem encryptor = AsymCryptoSystem.CreateFrom(this))
{
return(encryptor.EcdhGetKeyExchangeKey(encodingParms, nameAlg, out ephemPubPt));
}
}
} // VerifySignature()
/// <summary>
/// Generates the key exchange key and the public part of the ephemeral key
/// using specified encoding parameters in the KDF (ECC only).
/// </summary>
/// <param name="encodingParms"></param>
/// <param name="decryptKeyNameAlg"></param>
/// <param name="ephemPub"></param>
/// <returns>key exchange key blob</returns>
public byte[] EcdhGetKeyExchangeKey(byte[] encodingParms, TpmAlgId decryptKeyNameAlg, out EccPoint ephemPub)
{
byte[] keyExchangeKey = null;
ephemPub = null;
#if !__MonoCS__
var eccParms = (EccParms)PublicParms.parameters;
int keyBits = RawEccKey.GetKeyLength(eccParms.curveID);
// Make a new ephemeral key
#if TSS_USE_BCRYPT
var ephKey = Generate(RawEccKey.GetEccAlg(PublicParms), (uint)keyBits);
byte[] ephPub = ephKey.Export(Native.BCRYPT_ECCPUBLIC_BLOB);
byte[] otherPub = Key.Export(Native.BCRYPT_ECCPUBLIC_BLOB);
#else
using (var eph = new ECDiffieHellmanCng(keyBits))
{
byte[] otherPub = EcDhProvider.PublicKey.ToByteArray();
byte[] ephPub = eph.PublicKey.ToByteArray();
eph.KeyDerivationFunction = ECDiffieHellmanKeyDerivationFunction.Hash;
eph.HashAlgorithm = GetCngAlgorithm(decryptKeyNameAlg);
#endif // !TSS_USE_BCRYPT
byte[] herPubX, herPubY;
RawEccKey.KeyInfoFromPublicBlob(otherPub, out herPubX, out herPubY);
byte[] myPubX, myPubY;
RawEccKey.KeyInfoFromPublicBlob(ephPub, out myPubX, out myPubY);
byte[] otherInfo = Globs.Concatenate(new[] { encodingParms, myPubX, herPubX });
// The TPM uses the following number of bytes from the KDF
int bytesNeeded = CryptoLib.DigestSize(decryptKeyNameAlg);
keyExchangeKey = new byte[bytesNeeded];
for (int pos = 0, count = 1, bytesToCopy = 0;
pos < bytesNeeded;
++count, pos += bytesToCopy)
{
byte[] secretPrepend = Marshaller.GetTpmRepresentation((UInt32)count);
#if TSS_USE_BCRYPT
byte[] fragment = ephKey.DeriveKey(Key, decryptKeyNameAlg, secretPrepend, otherInfo);
#else
eph.SecretAppend = otherInfo;
eph.SecretPrepend = secretPrepend;
byte[] fragment = eph.DeriveKeyMaterial(EcDhProvider.Key);
#endif // !TSS_USE_BCRYPT
bytesToCopy = Math.Min(bytesNeeded - pos, fragment.Length);
Array.Copy(fragment, 0, keyExchangeKey, pos, bytesToCopy);
}
ephemPub = new EccPoint(myPubX, myPubY);
#if !TSS_USE_BCRYPT
}
#endif
#endif // !__MonoCS__
return(keyExchangeKey);
}
///<param name = "the_point">coordinates</param>
public Tpm2bEccPoint(
EccPoint the_point
)
{
this.point = the_point;
}
/// <summary>
/// Get an ECDH key exchange key (one pass ephemeral) and the public key of the ephemeral
/// key using ECDH with encodingParms as input to the KDF (ECC only)
/// </summary>
/// <param name="encodingParms"></param>
/// <param name="decryptKeyNameAlg"></param>
/// <param name="pubEphem"></param>
/// <returns></returns>
public byte[] EcdhGetKeyExchangeKey(byte[] encodingParms, TpmAlgId decryptKeyNameAlg, out EccPoint pubEphem)
{
using (AsymCryptoSystem encryptor = AsymCryptoSystem.CreateFrom(this))
{
return encryptor.EcdhGetKeyExchangeKey(encodingParms, decryptKeyNameAlg, out pubEphem);
}
}
public EccPoint Commit(
TpmHandle signHandle,
EccPoint P1,
byte[] s2,
byte[] y2,
[SuppressMessage("Microsoft.Design", "CA1021")]
out EccPoint L,
[SuppressMessage("Microsoft.Design", "CA1021")]
out EccPoint E,
[SuppressMessage("Microsoft.Design", "CA1021")]
out ushort counter
)
{
Tpm2CommitRequest inS = new Tpm2CommitRequest();
inS.signHandle = signHandle;
inS.P1 = P1;
inS.s2 = s2;
inS.y2 = y2;
TpmStructureBase outSBase;
DispatchMethod(TpmCc.Commit, (TpmStructureBase) inS, typeof(Tpm2CommitResponse), out outSBase, 1, 0);
Tpm2CommitResponse outS = (Tpm2CommitResponse) outSBase;
L = outS.L;
E = outS.E;
counter = outS.counter;
return outS.K;
}
public Tpm2bEccPoint()
{
point = new EccPoint();
}
public Tpm2EcEphemeralResponse()
{
Q = new EccPoint();
}
public EccPoint EcdhZGen(
TpmHandle keyHandle,
EccPoint inPoint
)
{
Tpm2EcdhZGenRequest inS = new Tpm2EcdhZGenRequest();
inS.keyHandle = keyHandle;
inS.inPoint = inPoint;
TpmStructureBase outSBase;
DispatchMethod(TpmCc.EcdhZGen, (TpmStructureBase) inS, typeof(Tpm2EcdhZGenResponse), out outSBase, 1, 0);
Tpm2EcdhZGenResponse outS = (Tpm2EcdhZGenResponse) outSBase;
return outS.outPoint;
}
public Tpm2EcdhZGenResponse(Tpm2EcdhZGenResponse the_Tpm2EcdhZGenResponse)
{
if((Object) the_Tpm2EcdhZGenResponse == null ) throw new ArgumentException(Globs.GetResourceString("parmError"));
outPoint = the_Tpm2EcdhZGenResponse.outPoint;
}
public Tpm2CommitResponse()
{
K = new EccPoint();
L = new EccPoint();
E = new EccPoint();
}
///<param name = "the_keyHandle">handle of a loaded ECC key Auth Index: 1 Auth Role: USER</param>
///<param name = "the_inPoint">a public key</param>
public Tpm2EcdhZGenRequest(
TpmHandle the_keyHandle,
EccPoint the_inPoint
)
{
this.keyHandle = the_keyHandle;
this.inPoint = the_inPoint;
}
public Tpm2EcdhZGenResponse()
{
outPoint = new EccPoint();
}
public Tpm2EcdhZGenRequest(Tpm2EcdhZGenRequest the_Tpm2EcdhZGenRequest)
{
if((Object) the_Tpm2EcdhZGenRequest == null ) throw new ArgumentException(Globs.GetResourceString("parmError"));
keyHandle = the_Tpm2EcdhZGenRequest.keyHandle;
inPoint = the_Tpm2EcdhZGenRequest.inPoint;
}
public Tpm2EcdhZGenRequest()
{
keyHandle = new TpmHandle();
inPoint = new EccPoint();
}
///<param name = "the_zPoint">results of P h[de]Qs</param>
///<param name = "the_pubPoint">generated ephemeral public point (Qe)</param>
public Tpm2EcdhKeyGenResponse(
EccPoint the_zPoint,
EccPoint the_pubPoint
)
{
this.zPoint = the_zPoint;
this.pubPoint = the_pubPoint;
}
public Tpm2EcdhKeyGenResponse()
{
zPoint = new EccPoint();
pubPoint = new EccPoint();
}
///<param name = "the_outPoint">X and Y coordinates of the product of the multiplication Z = (xZ , yZ) [hdS]QB</param>
public Tpm2EcdhZGenResponse(
EccPoint the_outPoint
)
{
this.outPoint = the_outPoint;
}
///<param name = "the_signHandle">handle of the key that will be used in the signing operation Auth Index: 1 Auth Role: USER</param>
///<param name = "the_P1">a point (M) on the curve used by signHandle</param>
///<param name = "the_s2">octet array used to derive x-coordinate of a base point</param>
///<param name = "the_y2">y coordinate of the point associated with s2</param>
public Tpm2CommitRequest(
TpmHandle the_signHandle,
EccPoint the_P1,
byte[] the_s2,
byte[] the_y2
)
{
this.signHandle = the_signHandle;
this.P1 = the_P1;
this.s2 = the_s2;
this.y2 = the_y2;
}
public Tpm2ZGen2PhaseRequest()
{
keyA = new TpmHandle();
inQsB = new EccPoint();
inQeB = new EccPoint();
inScheme = TpmAlgId.Null;
}
///<param name = "the_K">ECC point K [ds](x2, y2)</param>
///<param name = "the_L">ECC point L [r](x2, y2)</param>
///<param name = "the_E">ECC point E [r]P1</param>
///<param name = "the_counter">least-significant 16 bits of commitCount</param>
public Tpm2CommitResponse(
EccPoint the_K,
EccPoint the_L,
EccPoint the_E,
ushort the_counter
)
{
this.K = the_K;
this.L = the_L;
this.E = the_E;
this.counter = the_counter;
}
///<param name = "the_keyA">handle of an unrestricted decryption key ECC The private key referenced by this handle is used as dS,A Auth Index: 1 Auth Role: USER</param>
///<param name = "the_inQsB">other partys static public key (Qs,B = (Xs,B, Ys,B))</param>
///<param name = "the_inQeB">other party's ephemeral public key (Qe,B = (Xe,B, Ye,B))</param>
///<param name = "the_inScheme">the key exchange scheme</param>
///<param name = "the_counter">value returned by TPM2_EC_Ephemeral()</param>
public Tpm2ZGen2PhaseRequest(
TpmHandle the_keyA,
EccPoint the_inQsB,
EccPoint the_inQeB,
TpmAlgId the_inScheme,
ushort the_counter
)
{
this.keyA = the_keyA;
this.inQsB = the_inQsB;
this.inQeB = the_inQeB;
this.inScheme = the_inScheme;
this.counter = the_counter;
}
///<param name = "the_Q">ephemeral public key Q [r]G</param>
///<param name = "the_counter">least-significant 16 bits of commitCount</param>
public Tpm2EcEphemeralResponse(
EccPoint the_Q,
ushort the_counter
)
{
this.Q = the_Q;
this.counter = the_counter;
}
public Tpm2ZGen2PhaseResponse()
{
outZ1 = new EccPoint();
outZ2 = new EccPoint();
}
public EccPoint ZGen2Phase(
TpmHandle keyA,
EccPoint inQsB,
EccPoint inQeB,
TpmAlgId inScheme,
ushort counter,
[SuppressMessage("Microsoft.Design", "CA1021")]
out EccPoint outZ2
)
{
Tpm2ZGen2PhaseRequest inS = new Tpm2ZGen2PhaseRequest();
inS.keyA = keyA;
inS.inQsB = inQsB;
inS.inQeB = inQeB;
inS.inScheme = inScheme;
inS.counter = counter;
TpmStructureBase outSBase;
DispatchMethod(TpmCc.ZGen2Phase, (TpmStructureBase) inS, typeof(Tpm2ZGen2PhaseResponse), out outSBase, 1, 0);
Tpm2ZGen2PhaseResponse outS = (Tpm2ZGen2PhaseResponse) outSBase;
outZ2 = outS.outZ2;
return outS.outZ1;
}
public Tpm2ZGen2PhaseResponse(Tpm2ZGen2PhaseResponse the_Tpm2ZGen2PhaseResponse)
{
if((Object) the_Tpm2ZGen2PhaseResponse == null ) throw new ArgumentException(Globs.GetResourceString("parmError"));
outZ1 = the_Tpm2ZGen2PhaseResponse.outZ1;
outZ2 = the_Tpm2ZGen2PhaseResponse.outZ2;
}
public EccPoint(EccPoint the_EccPoint)
{
if((Object) the_EccPoint == null ) throw new ArgumentException(Globs.GetResourceString("parmError"));
x = the_EccPoint.x;
y = the_EccPoint.y;
}
///<param name = "the_outZ1">X and Y coordinates of the computed value (scheme dependent)</param>
///<param name = "the_outZ2">X and Y coordinates of the second computed value (scheme dependent)</param>
public Tpm2ZGen2PhaseResponse(
EccPoint the_outZ1,
EccPoint the_outZ2
)
{
this.outZ1 = the_outZ1;
this.outZ2 = the_outZ2;
}
public Tpm2bEccPoint(Tpm2bEccPoint the_Tpm2bEccPoint)
{
if((Object) the_Tpm2bEccPoint == null ) throw new ArgumentException(Globs.GetResourceString("parmError"));
point = the_Tpm2bEccPoint.point;
}
/// <summary>
/// Get an ECDH key exchange key (one pass ephemeral) and the public key of the ephemeral
/// key using ECDH with encodingParms as input to the KDF (ECC only)
/// </summary>
/// <param name="encodingParms"></param>
/// <param name="decryptKeyNameAlg"></param>
/// <param name="pubEphem"></param>
/// <returns></returns>
public byte[] EcdhGetKeyExchangeKey(byte[] encodingParms, TpmAlgId decryptKeyNameAlg, out EccPoint pubEphem)
{
using (AsymCryptoSystem encryptor = AsymCryptoSystem.CreateFrom(this))
{
return(encryptor.EcdhGetKeyExchangeKey(encodingParms, decryptKeyNameAlg, out pubEphem));
}
}
/// <summary>
/// Create a new random software key (public and private) matching the parameters in keyParams.
/// </summary>
/// <param name="keyParams"></param>
/// <returns></returns>
public AsymCryptoSystem(TpmPublic keyParams)
{
TpmAlgId keyAlgId = keyParams.type;
PublicParms = keyParams.Copy();
switch (keyAlgId)
{
case TpmAlgId.Rsa:
{
var rsaParams = keyParams.parameters as RsaParms;
#if TSS_USE_BCRYPT
Key = Generate(Native.BCRYPT_RSA_ALGORITHM, rsaParams.keyBits);
if (Key == UIntPtr.Zero)
{
Globs.Throw("Failed to generate RSA key");
return;
}
byte[] blob = Export(Native.BCRYPT_RSAPUBLIC_BLOB);
var m = new Marshaller(blob, DataRepresentation.LittleEndian);
var header = m.Get <BCryptRsaKeyBlob>();
/*var exponent = */ m.GetArray <byte>((int)header.cbPublicExp);
var modulus = m.GetArray <byte>((int)header.cbModulus);
#else
RsaProvider = new RSACryptoServiceProvider(rsaParams.keyBits);
var modulus = RsaProvider.ExportParameters(true).Modulus;
#endif
var pubId = new Tpm2bPublicKeyRsa(modulus);
PublicParms.unique = pubId;
break;
}
#if !__MonoCS__
case TpmAlgId.Ecc:
{
var eccParms = keyParams.parameters as EccParms;
var alg = RawEccKey.GetEccAlg(keyParams);
if (alg == null)
{
Globs.Throw <ArgumentException>("Unknown ECC curve");
return;
}
#if TSS_USE_BCRYPT
Key = Generate(alg, (uint)RawEccKey.GetKeyLength(eccParms.curveID));
#else
var keyParmsX = new CngKeyCreationParameters {
ExportPolicy = CngExportPolicies.AllowPlaintextExport
};
using (CngKey key = CngKey.Create(alg, null, keyParmsX))
{
byte[] keyIs = key.Export(CngKeyBlobFormat.EccPublicBlob);
CngKey.Import(keyIs, CngKeyBlobFormat.EccPublicBlob);
if (keyParams.objectAttributes.HasFlag(ObjectAttr.Sign))
{
EcdsaProvider = new ECDsaCng(key);
}
else
{
EcDhProvider = new ECDiffieHellmanCng(key);
}
// Store the public key
const int offset = 8;
int keySize = 0;
switch (eccParms.curveID)
{
case EccCurve.TpmEccNistP256:
case EccCurve.TpmEccBnP256:
case EccCurve.TpmEccSm2P256:
keySize = 32;
break;
case EccCurve.TpmEccNistP384:
keySize = 48;
break;
case EccCurve.TpmEccNistP521:
keySize = 66;
break;
default:
throw new NotImplementedException();
}
var pubId = new EccPoint(
Globs.CopyData(keyIs, offset, keySize),
Globs.CopyData(keyIs, offset + keySize, keySize));
PublicParms.unique = pubId;
}
#endif // !TSS_USE_BCRYPT
break;
}
#endif // !__MonoCS__
default:
Globs.Throw <ArgumentException>("Algorithm not supported");
break;
}
}
public Tpm2EcEphemeralResponse()
{
Q = new EccPoint();
counter = 0;
}
public Tpm2CommitRequest()
{
signHandle = new TpmHandle();
P1 = new EccPoint();
s2 = new byte[0];
y2 = new byte[0];
}
} // VerifySignature()
/// <summary>
/// Generates the key exchange key and the public part of the ephemeral key
/// using specified encoding parameters in the KDF (ECC only).
/// </summary>
/// <param name="encodingParms"></param>
/// <param name="decryptKeyNameAlg"></param>
/// <param name="ephemPub"></param>
/// <returns>key exchange key blob</returns>
public byte[] EcdhGetKeyExchangeKey(byte[] encodingParms, TpmAlgId decryptKeyNameAlg, out EccPoint ephemPub)
{
var eccParms = (EccParms)PublicParms.parameters;
int keyBits = RawEccKey.GetKeyLength(eccParms.curveID);
byte[] keyExchangeKey = null;
ephemPub = new EccPoint();
// Make a new ephemeral key
var prov = AsymmetricKeyAlgorithmProvider.OpenAlgorithm(RawEccKey.GetEccAlg(PublicParms));
var ephKey = prov.CreateKeyPair((uint)keyBits);
IBuffer ephPubBuf = ephKey.ExportPublicKey(CryptographicPublicKeyBlobType.BCryptEccFullPublicKey);
byte[] ephPub;
CryptographicBuffer.CopyToByteArray(ephPubBuf, out ephPub);
IBuffer otherPubBuf = Key.ExportPublicKey(CryptographicPublicKeyBlobType.BCryptEccFullPublicKey);
byte[] otherPub;
CryptographicBuffer.CopyToByteArray(otherPubBuf, out otherPub);
byte[] herPubX, herPubY;
RawEccKey.KeyInfoFromPublicBlob(otherPub, out herPubX, out herPubY);
byte[] myPubX, myPubY;
RawEccKey.KeyInfoFromPublicBlob(ephPub, out myPubX, out myPubY);
byte[] otherInfo = Globs.Concatenate(new[] { encodingParms, myPubX, herPubX });
// The TPM uses the following number of bytes from the KDF
int bytesNeeded = CryptoLib.DigestSize(decryptKeyNameAlg);
keyExchangeKey = new byte[bytesNeeded];
for (int pos = 0, count = 1, bytesToCopy = 0;
pos < bytesNeeded;
++count, pos += bytesToCopy)
{
byte[] secretPrepend = Marshaller.GetTpmRepresentation((UInt32)count);
string algName;
KeyDerivationParameters deriveParams;
switch (decryptKeyNameAlg)
{
case TpmAlgId.Kdf1Sp800108:
algName = KeyDerivationAlgorithmNames.Sp800108CtrHmacSha256;
deriveParams = KeyDerivationParameters.BuildForSP800108(CryptographicBuffer.CreateFromByteArray(secretPrepend), CryptographicBuffer.CreateFromByteArray(otherInfo));
break;
case TpmAlgId.Kdf1Sp80056a:
algName = KeyDerivationAlgorithmNames.Sp80056aConcatSha256;
deriveParams = KeyDerivationParameters.BuildForSP80056a(CryptographicBuffer.ConvertStringToBinary(algName, BinaryStringEncoding.Utf8),
CryptographicBuffer.ConvertStringToBinary("TPM", BinaryStringEncoding.Utf8),
CryptographicBuffer.CreateFromByteArray(secretPrepend),
CryptographicBuffer.ConvertStringToBinary("", BinaryStringEncoding.Utf8),
CryptographicBuffer.CreateFromByteArray(otherInfo));
break;
case TpmAlgId.Kdf2:
algName = KeyDerivationAlgorithmNames.Pbkdf2Sha256;
deriveParams = KeyDerivationParameters.BuildForPbkdf2(CryptographicBuffer.CreateFromByteArray(secretPrepend), 1000);
break;
default:
Globs.Throw <ArgumentException>("wrong KDF name");
return(null);
}
KeyDerivationAlgorithmProvider deriveProv = KeyDerivationAlgorithmProvider.OpenAlgorithm(algName);
IBuffer keyMaterial = CryptographicEngine.DeriveKeyMaterial(Key, deriveParams, (uint)keyBits);
byte[] fragment;
CryptographicBuffer.CopyToByteArray(keyMaterial, out fragment);
bytesToCopy = Math.Min(bytesNeeded - pos, fragment.Length);
Array.Copy(fragment, 0, keyExchangeKey, pos, bytesToCopy);
}
ephemPub = new EccPoint(myPubX, myPubY);
return(keyExchangeKey);
}
public Tpm2CommitRequest(Tpm2CommitRequest the_Tpm2CommitRequest)
{
if((Object) the_Tpm2CommitRequest == null ) throw new ArgumentException(Globs.GetResourceString("parmError"));
signHandle = the_Tpm2CommitRequest.signHandle;
P1 = the_Tpm2CommitRequest.P1;
s2 = the_Tpm2CommitRequest.s2;
y2 = the_Tpm2CommitRequest.y2;
}
public Tpm2CommitResponse()
{
K = new EccPoint();
L = new EccPoint();
E = new EccPoint();
counter = 0;
}
