/// <summary>
/// Returns if a self signed certificate is properly signed.
/// </summary>
private static bool IsSignatureValid(X509Certificate2 cert)
{
Org.BouncyCastle.X509.X509Certificate bcCert = new Org.BouncyCastle.X509.X509CertificateParser().ReadCertificate(cert.RawData);
try
{
bcCert.Verify(bcCert.GetPublicKey());
}
catch
{
return(false);
}
return(true);
}
/// <summary>
/// verify data signature with public key
/// </summary>
/// <param name="macdata">source data</param>
/// <param name="mac">signature string</param>
/// <param name="pkInfo">public key</param>
/// <returns>verify result</returns>
public static bool VerifyData(string macdata, string mac, string pkInfo)
{
byte[] data = Encoding.UTF8.GetBytes(macdata);
byte[] signature = Convert.FromBase64String(mac);
string pub;
if (!pkInfo.Contains("CERTIFICATE") && !pkInfo.Contains("PUBLIC KEY"))
{
pub = ReadPK(pkInfo);
}
else
{
pub = pkInfo;
}
Org.BouncyCastle.Crypto.Parameters.ECPublicKeyParameters ecdsaPublicKey = null;
if (pub.Contains("CERTIFICATE"))
{
Org.BouncyCastle.X509.X509Certificate cert = new Org.BouncyCastle.X509.X509CertificateParser().ReadCertificate(Encoding.UTF8.GetBytes(pub));
ecdsaPublicKey = (Org.BouncyCastle.Crypto.Parameters.ECPublicKeyParameters)cert.GetPublicKey();
}
else if (pub.Contains("PUBLIC KEY"))
{
TextReader ptr = new StringReader(pub);
Org.BouncyCastle.OpenSsl.PemReader pem = new Org.BouncyCastle.OpenSsl.PemReader(ptr);
ecdsaPublicKey = (Org.BouncyCastle.Crypto.Parameters.ECPublicKeyParameters)pem.ReadObject();
}
string curveName = "P-256";
var nistCurve = Org.BouncyCastle.Asn1.Nist.NistNamedCurves.GetByName(curveName);
return(nistCurve.Verify(ecdsaPublicKey, data, signature));
}