private TKey CreateKeyExchangeInfo(SymmetricAlgorithm keyExchangeAlgorithm)
{
if (keyExchangeAlgorithm == null)
{
throw ExceptionUtility.ArgumentNull(nameof(keyExchangeAlgorithm));
}
var keyExchange = new TKey();
var keyExchangeParameters = _publicKey.ExportParameters(false);
using (var keyExchangeAsym = CreateEphemeralAlgorithm(_publicKey.ProviderType, keyExchangeParameters))
{
byte[] encodedKeyExchangeInfo;
using (var keyExchangeAlg = keyExchangeAsym.CreateKeyExchange(keyExchangeParameters))
{
encodedKeyExchangeInfo = keyExchangeAlg.EncodeKeyExchange(keyExchangeAlgorithm, GostKeyExchangeExportMethod.CryptoProKeyExport);
}
var keyExchangeInfo = new Gost_28147_89_KeyExchangeInfo();
keyExchangeInfo.Decode(encodedKeyExchangeInfo);
keyExchange.SessionEncryptedKey = keyExchangeInfo;
keyExchange.TransportParameters = keyExchangeAsym.ExportParameters(false);
}
return(keyExchange);
}
public override SymmetricAlgorithm DecodePrivateKey(byte[] encodedKeyExchangeData, GostKeyExchangeExportMethod keyExchangeExportMethod)
{
if (encodedKeyExchangeData == null)
{
throw ExceptionUtility.ArgumentNull(nameof(encodedKeyExchangeData));
}
int keyExchangeExportAlgId;
if (keyExchangeExportMethod == GostKeyExchangeExportMethod.GostKeyExport)
{
keyExchangeExportAlgId = Constants.CALG_SIMPLE_EXPORT;
}
else if (keyExchangeExportMethod == GostKeyExchangeExportMethod.CryptoProKeyExport)
{
keyExchangeExportAlgId = Constants.CALG_PRO_EXPORT;
}
else
{
throw ExceptionUtility.ArgumentOutOfRange(nameof(keyExchangeExportMethod));
}
var providerHandle = CryptoApiHelper.GetProviderHandle(ProviderType);
var keyExchangeInfo = new Gost_28147_89_KeyExchangeInfo();
keyExchangeInfo.Decode(encodedKeyExchangeData);
using (var keyHandle = CryptoApiHelper.DuplicateKey(this.GetSafeHandle()))
{
CryptoApiHelper.SetKeyExchangeExportAlgId(ProviderType, keyHandle, keyExchangeExportAlgId);
var keyExchangeHandle = CryptoApiHelper.ImportKeyExchange(providerHandle, keyExchangeInfo, keyHandle);
return(new Gost_28147_89_SymmetricAlgorithm(ProviderType, providerHandle, keyExchangeHandle));
}
}
private SymmetricAlgorithm DecodeKeyExchangeInternal(byte[] encodedKeyExchangeData, int keyExchangeExportAlgId)
{
var keyExchangeInfo = new Gost_28147_89_KeyExchangeInfo();
keyExchangeInfo.Decode(encodedKeyExchangeData);
SafeKeyHandleImpl symKeyHandle;
SafeKeyHandleImpl keyExchangeHandle = null;
try
{
var importedKeyBytes = CryptoApiHelper.EncodePublicBlob(_keyExchangeParameters, _keySize, _signatureAlgId);
CryptoApiHelper.ImportCspBlob(importedKeyBytes, _provHandle, _keyHandle, out keyExchangeHandle);
CryptoApiHelper.SetKeyExchangeExportAlgId(ProviderType, keyExchangeHandle, keyExchangeExportAlgId);
symKeyHandle = CryptoApiHelper.ImportKeyExchange(_provHandle, keyExchangeInfo, keyExchangeHandle);
}
finally
{
keyExchangeHandle.TryDispose();
}
return(new Gost_28147_89_SymmetricAlgorithm(ProviderType, _provHandle, symKeyHandle));
}
