(C#) Generate CSR from Pre-Existing Private Key

Demonstrates how to generate a Certificate Signing Request (CSR) from a pre-existing RSA private key.

Note: This example requires Chilkat v9.5.0.65 or greater.

Chilkat .NET Downloads Chilkat .NET Framework Chilkat for .NET Core

// Note: Requires Chilkat v9.5.0.65 or greater.

// This requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

Chilkat.PrivateKey privKey = new Chilkat.PrivateKey();

// Load the private key from a file.
// (Chilkat provides the ability to load private keys from many different
// formats and sources..)
bool success = privKey.LoadEncryptedPemFile("qa_data/rsa/privKey1.pem","password");
if (!success) {
    Debug.WriteLine(privKey.LastErrorText);
    return;
}

// Create the CSR object and set properties.
Chilkat.Csr csr = new Chilkat.Csr();

// Specify the Common Name.  This is the only required property.
// For SSL/TLS certificates, this would be the domain name. 
// For email certificates this would be the email address. 
csr.CommonName = "mysubdomain.mydomain.com";

// Country Name (2 letter code)
csr.Country = "GB";

// State or Province Name (full name)
csr.State = "Yorks";

// Locality Name (eg, city)
csr.Locality = "York";

// Organization Name (eg, company)
csr.Company = "Internet Widgits Pty Ltd";

// Organizational Unit Name (eg, secion/division)
csr.CompanyDivision = "IT";

// Email address
csr.EmailAddress = "support@mydomain.com";

// Create the CSR using the private key.
string pemStr = csr.GenCsrPem(privKey);
if (csr.LastMethodSuccess != true) {
    Debug.WriteLine(csr.LastErrorText);
    return;
}

// Save the CSR..
Chilkat.FileAccess fac = new Chilkat.FileAccess();
fac.WriteEntireTextFile("qa_output/csr1.pem",pemStr,"utf-8",false);

// Show the CSR.
Debug.WriteLine(pemStr);

// Sample output:
// The CSR PEM can be checked here:
// https://www.networking4all.com/en/support/tools/csr+check/
// Copy-and-paste the PEM into the online CSR Decoding / CSR Verification form

// 	-----BEGIN CERTIFICATE REQUEST-----
// 	MIIC6jCCAdICAQAwgaQxITAfBgNVBAMMGG15c3ViZG9tYWluLm15ZG9tYWluLmNv
// 	bTELMAkGA1UEBhMCR0IxDjAMBgNVBAgMBVlvcmtzMQ0wCwYDVQQHDARZb3JrMSEw
// 	HwYDVQQKDBhJbnRlcm5ldCBXaWRnaXRzIFB0eSBMdGQxCzAJBgNVBAsMAklUMSMw
// 	IQYJKoZIhvcNAQkBFhRzdXBwb3J0QG15ZG9tYWluLmNvbTCCASIwDQYJKoZIhvcN
// 	AQEBBQADggEPADCCAQoCggEBALnQ0un/wF8whk+gPuiAlf3qvx14jgAOV6Erm6EB
// 	H7WACPCpnKcm/8KP+7uoPiwRQaENhMeCgf45vcivl2p6aAn/spLXyEkXyw2d8wFb
// 	YYAGRkiz4Xf7ASJiKuwcOtORz+sSDzgtdfokHfXU1cYeFE2yQhSdLUY5fMn425+g
// 	KoEEsRSjSDe6AKru4+4iGNrLKd8pB9IA5/jOE139IkWlB9r5fEPD5bUTsgqXk9eb
// 	68O0gc712V2eZK07N24lDmFC4bIMTD4csDWocR5hFHXj7NX7c8sOBDcpEb9mPIk4
// 	elxubnhkfnjhOi4J3lDHcT/0ALnbLhf9LnaiKqs+5VcVZvECAwEAAaAAMA0GCSqG
// 	SIb3DQEBBQUAA4IBAQC0AETLIcP3foh5nbu2hVFS8uCUNZ5hEIR1eXmYZmZoBQq2
// 	26ZAoT4CZwixlggC+n7WvAXJ5Pzxpl4wLV4loTiQzaKPX1w0ERo5ZRwLy0n56oG2
// 	6QG+WTViT1C8rlgtVwkCFNOXr0kSSRs8FdaPllqKxK1hxYSL7zwNpumsk39F2cDt
// 	vhcekvH0V3BuGrQFm3dKN/0azW6GOod9+Vq4VzSyOe3kp15oxLBsZOFOu/REujcw
// 	Tzu2jt1asQKUm60CZ9wNHpYepR0Ww40uP1slbehEaFDa6V8b60/tlHHmBbJ4/fy5
// 	hJnYCvjzFz4O9VtT+JtP9ldRHWV3KpZ8ne3AjD+F
// 	-----END CERTIFICATE REQUEST-----