I searched around, but I didn't find a clear example. I want to create a self-signed (self-)trusted certificate programmatically (C#), following these steps:
STEP 1:
Create a root CA certificate on the fly and add it to the certificate store in the folder "Trusted Root certification Authorities"
I want to do exactly what this command line tool does:
makecert.exe -sk RootCA -sky signature -pe -n CN=MY_CA -r -sr LocalMachine -ss Root MyCA.cer
STEP 2:
Create a certificate based on the previously created root CA certificate and put it in the certificate store, in the folder "Personal"
I want to do exactly what this command line tool does:
makecert.exe -sk server -sky exchange -pe -n CN=127.0.0.1 -ir LocalMachine -is Root -ic MyCA.cer -sr LocalMachine -ss My MyCertificate.cer
I want to obtain this:
I did that (see the following code - STEP 1). How do I make STEP 2? Target machines is Windows XP/7.
I tried both a pure .NET approach and Bouncy Castle library.
// STEP 1
mycerRoot = generateRootCertV1("MY_CA"); // Tried also generateRootCertV2(BouncyCastle)
addCertToStore(mycerRoot, StoreName.Root, StoreLocation.LocalMachine);
// STEP 2
mycer = generateCert("127.0.0.1", mycerRoot); // ?????? <-- Something like that How to implement generateCert??
addCertToStore(mycer, StoreName.My, StoreLocation.LocalMachine);
public static Org.BouncyCastle.X509.X509Certificate generateRootCertV2(string certName)
{
X509V1CertificateGenerator certGen = new X509V1CertificateGenerator();
X509Name CN = new X509Name("CN=" + certName);
RsaKeyPairGenerator keypairgen = new RsaKeyPairGenerator();
keypairgen.Init(new KeyGenerationParameters(new SecureRandom(new CryptoApiRandomGenerator()), 1024));
AsymmetricCipherKeyPair keypair = keypairgen.GenerateKeyPair();
certGen.SetSerialNumber(BigInteger.ProbablePrime(120, new Random()));
certGen.SetIssuerDN(CN);
certGen.SetNotAfter(DateTime.MaxValue);
certGen.SetNotBefore(DateTime.Now.Subtract(new TimeSpan(7, 0, 0, 0)));
certGen.SetSubjectDN(CN);
certGen.SetPublicKey(keypair.Public);
certGen.SetSignatureAlgorithm("MD5WithRSA");
Org.BouncyCastle.X509.X509Certificate newCert = certGen.Generate(keypair.Private);
return newCert;
}
public static X509Certificate2 GenerateRootCertV1(string HostNameOrIP_or_CertName)
{
X509Certificate2 cert = null;
try
{
using (CryptContext ctx = new CryptContext())
{
ctx.Open();
cert = ctx.CreateSelfSignedCertificate(
new SelfSignedCertProperties
{
IsPrivateKeyExportable = true,
KeyBitLength = 4096,
Name = new X500DistinguishedName("cn=" + HostNameOrIP_or_CertName),
ValidFrom = DateTime.Today.AddDays(-1),
ValidTo = DateTime.Today.AddYears(20),
});
}
}
catch (Exception ex)
{
}
return cert;
}
public static bool addCertToStore(X509Certificate2 cert, StoreName st, StoreLocation sl)
{
bool bRet = false;
try
{
X509Store store = new X509Store(st, sl);
store.Open(OpenFlags.ReadWrite);
if (cert != null)
{
byte[] pfx = cert.Export(X509ContentType.Pfx);
cert = new X509Certificate2(pfx, (string)null, X509KeyStorageFlags.PersistKeySet | X509KeyStorageFlags.MachineKeySet);
if (!certExists(store, cert.SubjectName.Name))
{
store.Add(cert);
bRet = true;
}
}
store.Close();
}
catch
{
}
return bRet;
}
I edited the answer to do the root certificate first and then issue an end entity certificate.
Here is some example of generating a self-signed certificate through Bouncy Castle:
public static X509Certificate2 GenerateSelfSignedCertificate(string subjectName, string issuerName, AsymmetricKeyParameter issuerPrivKey, int keyStrength = 2048)
{
// Generating Random Numbers
var randomGenerator = new CryptoApiRandomGenerator();
var random = new SecureRandom(randomGenerator);
// The Certificate Generator
var certificateGenerator = new X509V3CertificateGenerator();
// Serial Number
var serialNumber = BigIntegers.CreateRandomInRange(BigInteger.One, BigInteger.ValueOf(Int64.MaxValue), random);
certificateGenerator.SetSerialNumber(serialNumber);
// Signature Algorithm
const string signatureAlgorithm = "SHA256WithRSA";
certificateGenerator.SetSignatureAlgorithm(signatureAlgorithm);
// 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;
var notAfter = notBefore.AddYears(2);
certificateGenerator.SetNotBefore(notBefore);
certificateGenerator.SetNotAfter(notAfter);
// Subject Public Key
AsymmetricCipherKeyPair subjectKeyPair;
var keyGenerationParameters = new KeyGenerationParameters(random, keyStrength);
var keyPairGenerator = new RsaKeyPairGenerator();
keyPairGenerator.Init(keyGenerationParameters);
subjectKeyPair = keyPairGenerator.GenerateKeyPair();
certificateGenerator.SetPublicKey(subjectKeyPair.Public);
// Generating the Certificate
var issuerKeyPair = subjectKeyPair;
// Selfsign certificate
var certificate = certificateGenerator.Generate(issuerPrivKey, random);
// Corresponding private key
PrivateKeyInfo info = PrivateKeyInfoFactory.CreatePrivateKeyInfo(subjectKeyPair.Private);
// Merge into X509Certificate2
var x509 = new System.Security.Cryptography.X509Certificates.X509Certificate2(certificate.GetEncoded());
var seq = (Asn1Sequence)Asn1Object.FromByteArray(info.PrivateKey.GetDerEncoded());
if (seq.Count != 9)
throw new PemException("malformed sequence in RSA private key");
var rsa = new RsaPrivateKeyStructure(seq);
RsaPrivateCrtKeyParameters rsaparams = new RsaPrivateCrtKeyParameters(
rsa.Modulus, rsa.PublicExponent, rsa.PrivateExponent, rsa.Prime1, rsa.Prime2, rsa.Exponent1, rsa.Exponent2, rsa.Coefficient);
x509.PrivateKey = DotNetUtilities.ToRSA(rsaparams);
return x509;
}
public static AsymmetricKeyParameter GenerateCACertificate(string subjectName, int keyStrength = 2048)
{
// Generating Random Numbers
var randomGenerator = new CryptoApiRandomGenerator();
var random = new SecureRandom(randomGenerator);
// The Certificate Generator
var certificateGenerator = new X509V3CertificateGenerator();
// Serial Number
var serialNumber = BigIntegers.CreateRandomInRange(BigInteger.One, BigInteger.ValueOf(Int64.MaxValue), random);
certificateGenerator.SetSerialNumber(serialNumber);
// Signature Algorithm
const string signatureAlgorithm = "SHA256WithRSA";
certificateGenerator.SetSignatureAlgorithm(signatureAlgorithm);
// Issuer and Subject Name
var subjectDN = new X509Name(subjectName);
var issuerDN = subjectDN;
certificateGenerator.SetIssuerDN(issuerDN);
certificateGenerator.SetSubjectDN(subjectDN);
// Valid For
var notBefore = DateTime.UtcNow.Date;
var notAfter = notBefore.AddYears(2);
certificateGenerator.SetNotBefore(notBefore);
certificateGenerator.SetNotAfter(notAfter);
// Subject Public Key
AsymmetricCipherKeyPair subjectKeyPair;
var keyGenerationParameters = new KeyGenerationParameters(random, keyStrength);
var keyPairGenerator = new RsaKeyPairGenerator();
keyPairGenerator.Init(keyGenerationParameters);
subjectKeyPair = keyPairGenerator.GenerateKeyPair();
certificateGenerator.SetPublicKey(subjectKeyPair.Public);
// Generating the Certificate
var issuerKeyPair = subjectKeyPair;
// Selfsign certificate
var certificate = certificateGenerator.Generate(issuerKeyPair.Private, random);
var x509 = new System.Security.Cryptography.X509Certificates.X509Certificate2(certificate.GetEncoded());
// Add CA certificate to Root store
addCertToStore(cert, StoreName.Root, StoreLocation.CurrentUser);
return issuerKeyPair.Private;
}
And add to the store (your code slightly modified):
public static bool addCertToStore(System.Security.Cryptography.X509Certificates.X509Certificate2 cert, System.Security.Cryptography.X509Certificates.StoreName st, System.Security.Cryptography.X509Certificates.StoreLocation sl)
{
bool bRet = false;
try
{
X509Store store = new X509Store(st, sl);
store.Open(OpenFlags.ReadWrite);
store.Add(cert);
store.Close();
}
catch
{
}
return bRet;
}
And usage:
var caPrivKey = GenerateCACertificate("CN=root ca");
var cert = GenerateSelfSignedCertificate("CN=127.0.01", "CN=root ca", caPrivKey);
addCertToStore(cert, StoreName.My, StoreLocation.CurrentUser);
I have not compiled this example code after @wakeupneo comments. @wakeupneo, you might have to slightly edit the code and add proper extensions to each certificate.