/// <inheritdoc />
public byte[] Export(CryptographicPrivateKeyBlobType blobType)
{
try
{
if (blobType == CryptographicPrivateKeyBlobType.BCryptPrivateKey && this.eccPrivateKeyBlob != null)
{
// Imported keys are always ephemeral and cannot be exported.
// But we can make the API work if we have the private key data.
// Copy the key data before returning it to avoid sharing an array
// with the caller that would allow the caller to change our key data.
return(this.eccPrivateKeyBlob.CloneArray());
}
return(this.key.Export(CngAsymmetricKeyAlgorithmProvider.GetPlatformKeyBlobType(blobType)));
}
catch (CryptographicException ex)
{
if (ex.IsNotSupportedException())
{
throw new NotSupportedException(ex.Message, ex);
}
throw;
}
}
private ECDsaCng CreateCng()
{
var cng = new ECDsaCng(this.key);
// .NET Core 2.1 / UAP has a bug where it throws NullReferenceException from SignHash because it didn't set this property.
if (cng.HashAlgorithm is null)
{
if (CngAsymmetricKeyAlgorithmProvider.GetHashCngAlgorithm(this.algorithm) is { } algorithm)
{
cng.HashAlgorithm = algorithm;
}
else
{
throw new NotSupportedException("Hash algorithm " + this.algorithm + " could not be obtained.");
}
}
/// <inheritdoc />
public byte[] ExportPublicKey(CryptographicPublicKeyBlobType blobType)
{
return(this.key.Export(CngAsymmetricKeyAlgorithmProvider.GetPlatformKeyBlobType(blobType)));
}