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Unicode C

Get Certificate User Principal Name (UPN)

See more Certificates Examples

Demonstrates how to get a certificate's UPN from the SAN (Subject Alternative Name). Most certificates do not have a UPN. This example only applies to those certificates that have a User Principal Name.

Note: This example requires Chilkat v9.5.0.90 or greater due to fixes made in getting the UPN from the SAN.

Chilkat Unicode C Downloads

Unicode C
#include <C_CkCertW.h>
#include <C_CkXmlW.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkCertW cert;
    HCkXmlW xml;
    const wchar_t *upn;

    success = FALSE;

    cert = CkCertW_Create();

    success = CkCertW_LoadFromFile(cert,L"qa_data/certs/sample.cer");
    if (success == FALSE) {
        wprintf(L"%s\n",CkCertW_lastErrorText(cert));
        CkCertW_Dispose(cert);
        return;
    }

    xml = CkXmlW_Create();
    CkXmlW_LoadXml(xml,CkCertW_subjectAlternativeName(cert));
    wprintf(L"%s\n",CkXmlW_getXml(xml));

    // A certificate with a User Principal Name in the SAN might have this:

    // <SubjectAltName>
    //     <rfc822Name>joe@example.com</rfc822Name>
    //     <name type="oid" oid="1.3.6.1.4.1.311.20.2.3">joe@example.com</name>
    // </SubjectAltName>

    // The OID 1.3.6.1.4.1.311.20.2.3 is for the User Principal Name.
    upn = CkXmlW_chilkatPath(xml,L"/A/name,oid,1.3.6.1.4.1.311.20.2.3|*");
    if (CkXmlW_getLastMethodSuccess(xml) == FALSE) {
        wprintf(L"No user principle name.\n");
    }
    else {
        wprintf(L"User Principle Name = %s\n",upn);
    }



    CkCertW_Dispose(cert);
    CkXmlW_Dispose(xml);

    }