(C#) Generate a CSR containing an Extension Request

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Demonstrates how to generate a CSR containing a 1.2.840.113549.1.9.14 extensionRequest.

Note: This example requires Chilkat v9.5.0.91 or greater.

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

// This example will generate a secp256r1 ECDSA key for the CSR.
Chilkat.Ecc ecc = new Chilkat.Ecc();
Chilkat.Prng prng = new Chilkat.Prng();

Chilkat.PrivateKey privKey = ecc.GenEccKey("secp256r1",prng);
if (ecc.LastMethodSuccess == false) {
    Debug.WriteLine("Failed to generate a new ECDSA private key.");
    return;
}

Chilkat.Csr csr = new Chilkat.Csr();

// Add common CSR fields:
csr.CommonName = "mysubdomain.mydomain.com";
csr.Country = "GB";
csr.State = "Yorks";
csr.Locality = "York";
csr.Company = "Internet Widgits Pty Ltd";
csr.EmailAddress = "support@mydomain.com";

// Add the following 1.2.840.113549.1.9.14 extensionRequest
// Note: The easiest way to know the content and format of the XML to be added is to examine
// a pre-existing CSR with the same desired extensionRequest.  You can use Chilkat to
// get the extensionRequest from an existing CSR. 

// 
// Here is a sample extension request:

// <?xml version="1.0" encoding="utf-8"?>
// <set>
//    <sequence>
//        <sequence>
//            <oid>1.3.6.1.4.1.311.20.2</oid>
//            <asnOctets>
//                <printable>ZATCA-Code-Signing</printable>
//            </asnOctets>
//        </sequence>
//        <sequence>
//            <oid>2.5.29.17</oid>
//            <asnOctets>
//                <sequence>
//                    <contextSpecific tag="4" constructed="1">
//                        <sequence>
//                            <set>
//                                <sequence>
//                                    <oid>2.5.4.4</oid>
//                                    <utf8>334623324234325</utf8>
//                                </sequence>
//                            </set>
//                            <set>
//                                <sequence>
//                                    <oid>0.9.2342.19200300.100.1.1</oid>
//                                    <utf8>310122393500003</utf8>
//                                </sequence>
//                            </set>
//                            <set>
//                                <sequence>
//                                    <oid>2.5.4.12</oid>
//                                    <utf8>0000</utf8>
//                                </sequence>
//                            </set>
//                            <set>
//                                <sequence>
//                                    <oid>2.5.4.26</oid>
//                                    <utf8>Sample E</utf8>
//                                </sequence>
//                            </set>
//                            <set>
//                                <sequence>
//                                    <oid>2.5.4.15</oid>
//                                    <utf8>Sample Business</utf8>
//                                </sequence>
//                            </set>
//                        </sequence>
//                    </contextSpecific>
//                </sequence>
//            </asnOctets>
//        </sequence>
//    </sequence>
// </set>

// Use this online tool to generate code from sample XML: 
// Generate Code to Create XML

// Here's the code to generate the above extension request.

Chilkat.Xml xml = new Chilkat.Xml();
xml.Tag = "set";
xml.UpdateChildContent("sequence|sequence|oid","1.3.6.1.4.1.311.20.2");
xml.UpdateChildContent("sequence|sequence|asnOctets|printable","ZATCA-Code-Signing");
xml.UpdateChildContent("sequence|sequence[1]|oid","2.5.29.17");
xml.UpdateAttrAt("sequence|sequence[1]|asnOctets|sequence|contextSpecific",true,"tag","4");
xml.UpdateAttrAt("sequence|sequence[1]|asnOctets|sequence|contextSpecific",true,"constructed","1");
xml.UpdateChildContent("sequence|sequence[1]|asnOctets|sequence|contextSpecific|sequence|set|sequence|oid","2.5.4.4");
xml.UpdateChildContent("sequence|sequence[1]|asnOctets|sequence|contextSpecific|sequence|set|sequence|utf8","334623324234325");
xml.UpdateChildContent("sequence|sequence[1]|asnOctets|sequence|contextSpecific|sequence|set[1]|sequence|oid","0.9.2342.19200300.100.1.1");
xml.UpdateChildContent("sequence|sequence[1]|asnOctets|sequence|contextSpecific|sequence|set[1]|sequence|utf8","310122393500003");
xml.UpdateChildContent("sequence|sequence[1]|asnOctets|sequence|contextSpecific|sequence|set[2]|sequence|oid","2.5.4.12");
xml.UpdateChildContent("sequence|sequence[1]|asnOctets|sequence|contextSpecific|sequence|set[2]|sequence|utf8","0000");
xml.UpdateChildContent("sequence|sequence[1]|asnOctets|sequence|contextSpecific|sequence|set[3]|sequence|oid","2.5.4.26");
xml.UpdateChildContent("sequence|sequence[1]|asnOctets|sequence|contextSpecific|sequence|set[3]|sequence|utf8","Sample E");
xml.UpdateChildContent("sequence|sequence[1]|asnOctets|sequence|contextSpecific|sequence|set[4]|sequence|oid","2.5.4.15");
xml.UpdateChildContent("sequence|sequence[1]|asnOctets|sequence|contextSpecific|sequence|set[4]|sequence|utf8","Sample Business");

// Add the extension request to the CSR
csr.SetExtensionRequest(xml);

// Generate the CSR with the extension request
string csrPem = csr.GenCsrPem(privKey);
if (csr.LastMethodSuccess == false) {
    Debug.WriteLine(csr.LastErrorText);

    return;
}

Debug.WriteLine(csrPem);

// Sample PEM output:

// -----BEGIN CERTIFICATE REQUEST-----
// MIICEjCCAbkCAQAwgZcxITAfBgNVBAMMGG15c3ViZG9tYWluLm15ZG9tYWluLmNv
// bTELMAkGA1UEBhMCR0IxDjAMBgNVBAgMBVlvcmtzMQ0wCwYDVQQHDARZb3JrMSEw
// HwYDVQQKDBhJbnRlcm5ldCBXaWRnaXRzIFB0eSBMdGQxIzAhBgkqhkiG9w0BCQEW
// FHN1cHBvcnRAbXlkb21haW4uY29tMFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAE
// g8EVNSV0ttlM9kG2E+J3ZB9WEDYVf2QA/8idrPRUafia1CHjd1kslwZA8eP2bAcf
// 2O493QAENqtW6DTHJbRz8KCBvjCBuwYJKoZIhvcNAQkOMYGtMIGqMCEGCSsGAQQB
// gjcUAgQUExJaQVRDQS1Db2RlLVNpZ25pbmcwgYQGA1UdEQR9MHukeTB3MRgwFgYD
// VQQEDA8zMzQ2MjMzMjQyMzQzMjUxHzAdBgoJkiaJk/IsZAEBDA8zMTAxMjIzOTM1
// MDAwMDMxDTALBgNVBAwMBDAwMDAxETAPBgNVBBoMCFNhbXBsZSBFMRgwFgYDVQQP
// DA9TYW1wbGUgQnVzaW5lc3MwCgYIKoZIzj0EAwIDRwAwRAIgF7D30eSBklfo+oel
// 1B0z64eJDB9MB3rCoiFZlj+mz0YCIHYI87eyqdtw2LOcAoBRhyxlBT6i28+Z/8t9
// bYsMIYvp
// -----END CERTIFICATE REQUEST-----