public static void AddSigner_ECDSA_EphemeralKey()
{
using (ECDsa ecdsa = ECDsa.Create())
using (X509Certificate2 publicCertificate = Certificates.ECDsaP256Win.GetCertificate())
using (X509Certificate2 certificateWithKey = Certificates.ECDsaP256Win.TryGetCertificateWithPrivateKey(exportable: true))
{
if (certificateWithKey == null)
{
return;
}
using (ECDsa privateKey = certificateWithKey.GetECDsaPrivateKey())
using (ECDsa exportableKey = privateKey.MakeExportable())
{
ecdsa.ImportParameters(exportableKey.ExportParameters(true));
}
using (X509Certificate2 certWithEphemeralKey = publicCertificate.CopyWithPrivateKey(ecdsa))
{
ContentInfo content = new ContentInfo(new byte[] { 1, 2, 3 });
SignedCms cms = new SignedCms(content, false);
CmsSigner signer = new CmsSigner(certWithEphemeralKey);
cms.ComputeSignature(signer);
}
}
}
