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Java

Duplicate CSR Created by OpenSSL with Config.cnf

See more CSR Examples

Demonstrates how to duplicate a CSR created by the following commands:
# Generate Private Key
openssl ecparam -name secp256k1 -genkey -noout -out PrivateKey.pem

#Generate CSR
openssl req -new -sha256 -key PrivateKey.pem -extensions v3_req -config Config.cnf -out CSR.csr

Chilkat Java Downloads

Java
import com.chilkatsoft.*;

public class ChilkatExample {

  static {
    try {
        System.loadLibrary("chilkat");
    } catch (UnsatisfiedLinkError e) {
      System.err.println("Native code library failed to load.\n" + e);
      System.exit(1);
    }
  }

  public static void main(String argv[])
  {
    boolean success = false;

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

    // This example duplicates the CSR created by OpenSSL with the following config file:

    // oid_section = OIDs
    // [ OIDs ]
    // certificateTemplateName= 1.3.6.1.4.1.311.20.2
    // 
    // [ req ]
    // default_bits 	= 2048
    // emailAddress 	= it@example.sa
    // req_extensions	= v3_req
    // x509_extensions 	= v3_ca
    // prompt = no
    // default_md = sha256
    // req_extensions = req_ext
    // distinguished_name = dn
    // 
    // [ v3_req ]
    // basicConstraints = CA:FALSE
    // keyUsage = digitalSignature, nonRepudiation, keyEncipherment
    // 
    // [req_ext]
    // certificateTemplateName = ASN1:PRINTABLESTRING:ZATCA-Code-Signing
    // subjectAltName = dirName:alt_names
    // 
    // [ dn ]
    // CN =EXAMPLE-CORP  				# Common Name
    // C=SA									# Country Code e.g SA
    // OU=HEAD-OFFICE							# Organization Unit Name
    // O=ASC									# Organization Name
    // 
    // [alt_names]
    // SN=1-ASC|2-V01|3-1234567890				# EGS Serial Number 1-ABC|2-PQR|3-XYZ
    // UID=312345678900003						# Organization Identifier (VAT Number)
    // title=1100								# Invoice Type
    // registeredAddress=Dammam  	 			# Address
    // businessCategory=IT						# Business Category

    // The OpenSSL commands we are duplicating:

    // openssl ecparam -name secp256k1 -genkey -noout -out PrivateKey.pem
    // openssl req -new -sha256 -key PrivateKey.pem -extensions v3_req -config Config.cnf -out CSR.csr

    // The 1st step is to actually use OpenSSL to generate a sample CSR.csr that we wish to duplicate.
    // With the sample CSR.csr, we get the ExtensionRequest as XML.  
    // For example:

    CkStringBuilder sbCsr = new CkStringBuilder();
    success = sbCsr.LoadFile("qa_data/csr/openssl_cnf/CSR.csr","utf-8");
    if (success == false) {
        System.out.println("Failed to load CSR.csr");
        return;
        }

    CkCsr csr0 = new CkCsr();
    success = csr0.LoadCsrPem(sbCsr.getAsString());
    if (success == false) {
        System.out.println(csr0.lastErrorText());
        return;
        }

    CkXml xml0 = new CkXml();
    success = csr0.GetExtensionRequest(xml0);
    if (success == false) {
        System.out.println(csr0.lastErrorText());
        return;
        }

    // Let's examine the extension request..
    System.out.println(xml0.getXml());

    // <?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>1-ASC|2-V01|3-1234567890</utf8>
    //                                 </sequence>
    //                             </set>
    //                             <set>
    //                                 <sequence>
    //                                     <oid>0.9.2342.19200300.100.1.1</oid>
    //                                     <utf8>312345678900003</utf8>
    //                                 </sequence>
    //                             </set>
    //                             <set>
    //                                 <sequence>
    //                                     <oid>2.5.4.12</oid>
    //                                     <utf8>1100</utf8>
    //                                 </sequence>
    //                             </set>
    //                             <set>
    //                                 <sequence>
    //                                     <oid>2.5.4.26</oid>
    //                                     <utf8>Dammam</utf8>
    //                                 </sequence>
    //                             </set>
    //                             <set>
    //                                 <sequence>
    //                                     <oid>2.5.4.15</oid>
    //                                     <utf8>IT</utf8>
    //                                 </sequence>
    //                             </set>
    //                         </sequence>
    //                     </contextSpecific>
    //                 </sequence>
    //             </asnOctets>
    //         </sequence>
    //     </sequence>
    // </set>

    // If you wish to generate the above XML without going through the above steps, copy the XML into
    // the online tool at https://tools.chilkat.io/xmlCreate

    // Here is the generated code for the above XML:

    CkXml xml = new CkXml();
    xml.put_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","1-ASC|2-V01|3-1234567890");
    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","312345678900003");
    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","1100");
    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","Dammam");
    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","IT");

    // We'll need a new secp256k1 private key, so let's generate it.
    CkEcc ecdsa = new CkEcc();
    CkPrng prng = new CkPrng();
    CkPrivateKey privKey = new CkPrivateKey();
    success = ecdsa.GenKey("secp256k1",prng,privKey);
    if (success == false) {
        System.out.println(ecdsa.lastErrorText());
        return;
        }

    System.out.println("Generated secp256k1 private key.");

    // Use a new CSR object to generate a CSR with the private key and extension request.
    CkCsr csr = new CkCsr();

    // Add the [dn] fields
    //  [ dn ]
    //  CN =EXAMPLE-CORP  				# Common Name
    //  C=SA									# Country Code e.g SA
    //  OU=HEAD-OFFICE							# Organization Unit Name
    //  O=ASC									# Organization Name
    csr.put_CommonName("EXAMPLE-CORP");
    csr.put_Country("SA");
    csr.put_CompanyDivision("HEAD-OFFICE");
    csr.put_Company("ASC");

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

    // Generate the CSR with the extension request
    String csrPem = csr.genCsrPem(privKey);
    if (csr.get_LastMethodSuccess() == false) {
        System.out.println(csr.lastErrorText());
        return;
        }

    System.out.println(csrPem);

    // Sample output:

    // -----BEGIN CERTIFICATE REQUEST-----
    // MIIBuDCCAV8CAQAwSDEVMBMGA1UEAwwMRVhBTVBMRS1DT1JQMQswCQYDVQQGEwJT
    // QTEUMBIGA1UECwwLSEVBRC1PRkZJQ0UxDDAKBgNVBAoMA0FTQzBWMBAGByqGSM49
    // AgEGBSuBBAAKA0IABFI5rusr76HiJcMMr1r4L0B0BOAs6azLkt/RwHoT6A0xFRRt
    // tulWT40tNhx3qJ4I5ePNgMceOEtuK1kMGVTovI6ggbcwgbQGCSqGSIb3DQEJDjGB
    // pjCBozAhBgkrBgEEAYI3FAIEFBMSWkFUQ0EtQ29kZS1TaWduaW5nMH4GA1UdEQR3
    // MHWkczBxMSEwHwYDVQQEDBgxLUFTQ3wyLVYwMXwzLTEyMzQ1Njc4OTAxHzAdBgoJ
    // kiaJk/IsZAEBDA8zMTIzNDU2Nzg5MDAwMDMxDTALBgNVBAwMBDExMDAxDzANBgNV
    // BBoMBkRhbW1hbTELMAkGA1UEDwwCSVQwCgYIKoZIzj0EAwIDRwAwRAIgJnbgpSGb
    // diB+0M1VTqc1GU9sFsfnOvVN/8WhWRRxQIwCIF5eH9vgMgXyoU284X8Bx3dqOJ4q
    // xashGWci87POxSvT
    // -----END CERTIFICATE REQUEST-----
  }
}