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Unicode C

Generate a CSR containing an Extension Request

See more CSR Examples

Demonstrates how to generate a CSR containing a 1.2.840.113549.1.9.14 extensionRequest.

Chilkat Unicode C Downloads

Unicode C
#include <C_CkEccW.h>
#include <C_CkPrngW.h>
#include <C_CkPrivateKeyW.h>
#include <C_CkCsrW.h>
#include <C_CkXmlW.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkEccW ecc;
    HCkPrngW prng;
    HCkPrivateKeyW privKey;
    HCkCsrW csr;
    HCkXmlW xml;
    const wchar_t *csrPem;

    success = FALSE;

    //  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.
    ecc = CkEccW_Create();
    prng = CkPrngW_Create();
    privKey = CkPrivateKeyW_Create();

    success = CkEccW_GenKey(ecc,L"secp256r1",prng,privKey);
    if (success == FALSE) {
        wprintf(L"Failed to generate a new ECDSA private key.\n");
        CkEccW_Dispose(ecc);
        CkPrngW_Dispose(prng);
        CkPrivateKeyW_Dispose(privKey);
        return;
    }

    csr = CkCsrW_Create();

    //  Add common CSR fields:
    CkCsrW_putCommonName(csr,L"mysubdomain.mydomain.com");
    CkCsrW_putCountry(csr,L"GB");
    CkCsrW_putState(csr,L"Yorks");
    CkCsrW_putLocality(csr,L"York");
    CkCsrW_putCompany(csr,L"Internet Widgits Pty Ltd");
    CkCsrW_putEmailAddress(csr,L"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.

    xml = CkXmlW_Create();
    CkXmlW_putTag(xml,L"set");
    CkXmlW_UpdateChildContent(xml,L"sequence|sequence|oid",L"1.3.6.1.4.1.311.20.2");
    CkXmlW_UpdateChildContent(xml,L"sequence|sequence|asnOctets|printable",L"ZATCA-Code-Signing");
    CkXmlW_UpdateChildContent(xml,L"sequence|sequence[1]|oid",L"2.5.29.17");
    CkXmlW_UpdateAttrAt(xml,L"sequence|sequence[1]|asnOctets|sequence|contextSpecific",TRUE,L"tag",L"4");
    CkXmlW_UpdateAttrAt(xml,L"sequence|sequence[1]|asnOctets|sequence|contextSpecific",TRUE,L"constructed",L"1");
    CkXmlW_UpdateChildContent(xml,L"sequence|sequence[1]|asnOctets|sequence|contextSpecific|sequence|set|sequence|oid",L"2.5.4.4");
    CkXmlW_UpdateChildContent(xml,L"sequence|sequence[1]|asnOctets|sequence|contextSpecific|sequence|set|sequence|utf8",L"334623324234325");
    CkXmlW_UpdateChildContent(xml,L"sequence|sequence[1]|asnOctets|sequence|contextSpecific|sequence|set[1]|sequence|oid",L"0.9.2342.19200300.100.1.1");
    CkXmlW_UpdateChildContent(xml,L"sequence|sequence[1]|asnOctets|sequence|contextSpecific|sequence|set[1]|sequence|utf8",L"310122393500003");
    CkXmlW_UpdateChildContent(xml,L"sequence|sequence[1]|asnOctets|sequence|contextSpecific|sequence|set[2]|sequence|oid",L"2.5.4.12");
    CkXmlW_UpdateChildContent(xml,L"sequence|sequence[1]|asnOctets|sequence|contextSpecific|sequence|set[2]|sequence|utf8",L"0000");
    CkXmlW_UpdateChildContent(xml,L"sequence|sequence[1]|asnOctets|sequence|contextSpecific|sequence|set[3]|sequence|oid",L"2.5.4.26");
    CkXmlW_UpdateChildContent(xml,L"sequence|sequence[1]|asnOctets|sequence|contextSpecific|sequence|set[3]|sequence|utf8",L"Sample E");
    CkXmlW_UpdateChildContent(xml,L"sequence|sequence[1]|asnOctets|sequence|contextSpecific|sequence|set[4]|sequence|oid",L"2.5.4.15");
    CkXmlW_UpdateChildContent(xml,L"sequence|sequence[1]|asnOctets|sequence|contextSpecific|sequence|set[4]|sequence|utf8",L"Sample Business");

    //  Add the extension request to the CSR
    CkCsrW_SetExtensionRequest(csr,xml);

    //  Generate the CSR with the extension request
    csrPem = CkCsrW_genCsrPem(csr,privKey);
    if (CkCsrW_getLastMethodSuccess(csr) == FALSE) {
        wprintf(L"%s\n",CkCsrW_lastErrorText(csr));
        CkEccW_Dispose(ecc);
        CkPrngW_Dispose(prng);
        CkPrivateKeyW_Dispose(privKey);
        CkCsrW_Dispose(csr);
        CkXmlW_Dispose(xml);
        return;
    }

    wprintf(L"%s\n",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-----


    CkEccW_Dispose(ecc);
    CkPrngW_Dispose(prng);
    CkPrivateKeyW_Dispose(privKey);
    CkCsrW_Dispose(csr);
    CkXmlW_Dispose(xml);

    }