public static X509Certificate2 AddPemPrivateKeyToCertificate(X509Certificate2 certificate, byte[] privateKeyBuffer)
{
try
{
var keyPair = ReadPrivateKey(privateKeyBuffer);
var rsaPrivateKey = PemUtilsHelper.ToRSA(keyPair.Private as RsaPrivateCrtKeyParameters);
certificate = certificate.CopyWithPrivateKey(rsaPrivateKey);
return(certificate);
}
catch (Exception ex)
{
logger.Error(ex, $"The Method \"{nameof(AddPemPrivateKeyToCertificate)}\" has failed.");
return(null);
}
}
protected RSACryptoServiceProvider GetRsaProvider()
{
var rsaParameters = new RSAParameters();
if (HasPrivateKey)
{
rsaParameters = PemUtilsHelper.ToRSAParameters(PrivateKey);
}
else
{
rsaParameters = PemUtilsHelper.ToRSAParameters(PublicKey);
}
var rsa = new RSACryptoServiceProvider();
rsa.ImportParameters(rsaParameters);
return(rsa);
}
public bool ValidSignature(string data, string base64Data, HashAlgorithmName hashAlgorithm)
{
try
{
var sha = new SHA256CryptoServiceProvider();
var hash = sha.ComputeHash(Encoding.UTF8.GetBytes(data));
var signature = Convert.FromBase64String(base64Data);
using RSA rsa = RSA.Create();
var rsaParameters = PemUtilsHelper.ToRSAParameters(PrivateKey);
rsa.ImportParameters(rsaParameters);
return(rsa.VerifyHash(hash, signature, hashAlgorithm, RSASignaturePadding.Pss));
}
catch (Exception ex)
{
throw new Exception("The public key could not be properly verified.", ex);
}
}
public string SignWithPrivateKey(string data, HashAlgorithmName hashAlgorithm, bool useIndent = false)
{
try
{
using RSA rsa = RSA.Create();
var rsaParameters = PemUtilsHelper.ToRSAParameters(PrivateKey);
rsa.ImportParameters(rsaParameters);
var sha = new SHA256CryptoServiceProvider();
var hash = sha.ComputeHash(Encoding.UTF8.GetBytes(data));
var signature = rsa.SignHash(hash, hashAlgorithm, RSASignaturePadding.Pss);
if (useIndent)
{
return(Convert.ToBase64String(signature, Base64FormattingOptions.InsertLineBreaks));
}
return(Convert.ToBase64String(signature));
}
catch (Exception ex)
{
throw new Exception("Data could not signing.", ex);
}
}
public static X509Certificate2 GenerateSelfSignedCertificate(string subjectName, string issuerName, int keyStrength)
{
try
{
// Generating Random Numbers
var randomGenerator = new VmpcRandomGenerator();
var random = new SecureRandom(randomGenerator);
// The Certificate Generator
var certificateGenerator = new X509V3CertificateGenerator();
// Serial Number
var serialNumber = BigInteger.ProbablePrime(128, new Random());
certificateGenerator.SetSerialNumber(serialNumber);
// Issuer and Subject Name
var subjectDN = new X509Name(subjectName);
var issuerDN = new X509Name(issuerName);
certificateGenerator.SetIssuerDN(issuerDN);
certificateGenerator.SetSubjectDN(subjectDN);
// Valid For
var notBefore = DateTime.UtcNow.Date.AddYears(-1);
var notAfter = notBefore.AddYears(10);
certificateGenerator.SetNotBefore(notBefore);
certificateGenerator.SetNotAfter(notAfter);
// Subject Public Key
var keyGenerationParameters = new KeyGenerationParameters(random, keyStrength);
var keyPairGenerator = new RsaKeyPairGenerator();
keyPairGenerator.Init(keyGenerationParameters);
if (userKeyPair == null)
{
userKeyPair = keyPairGenerator.GenerateKeyPair();
}
certificateGenerator.SetPublicKey(userKeyPair.Public);
//Extented
certificateGenerator.AddExtension(X509Extensions.SubjectKeyIdentifier, false,
new SubjectKeyIdentifierStructure(userKeyPair.Public));
certificateGenerator.AddExtension(X509Extensions.AuthorityKeyIdentifier, false,
new AuthorityKeyIdentifier(SubjectPublicKeyInfoFactory
.CreateSubjectPublicKeyInfo(userKeyPair.Public)));
var valueData = Encoding.ASCII.GetBytes("Client");
certificateGenerator.AddExtension("1.3.6.1.5.5.7.13.3", false, valueData);
// Generating the Certificate
var issuerKeyPair = userKeyPair;
// Signature Algorithm
ISignatureFactory signatureFactory = new Asn1SignatureFactory("SHA512WITHRSA", userKeyPair.Private, random);
// selfsign certificate
var certificate = certificateGenerator.Generate(signatureFactory);
// correcponding private key
var info = PrivateKeyInfoFactory.CreatePrivateKeyInfo(userKeyPair.Private);
// merge into X509Certificate2
var x509 = new X509Certificate2(certificate.GetEncoded());
var seq = (Asn1Sequence)info.ParsePrivateKey();
if (seq.Count != 9)
{
throw new Exception("malformed sequence in RSA private key");
}
var rsa = RsaPrivateKeyStructure.GetInstance(seq);
var rsaparams = new RsaPrivateCrtKeyParameters(rsa.Modulus, rsa.PublicExponent, rsa.PrivateExponent,
rsa.Prime1, rsa.Prime2, rsa.Exponent1, rsa.Exponent2,
rsa.Coefficient);
x509 = x509.CopyWithPrivateKey(PemUtilsHelper.ToRSA(rsaparams));
return(x509);
}
catch (Exception ex)
{
logger.Error(ex, $"The Method \"{nameof(GenerateSelfSignedCertificate)}\" has failed.");
return(null);
}
}
