(MFC) Sign PDF with Timestamp from TSA (Timestamp Server Authority)

See more PDF Signatures Examples

This example demonstrates how to a sign a PDF that is both long-term validation (LTV) enabled and includes a validating timestamp from a TSA (Timestamp Server Authority).

Note: This example requires Chilkat v9.5.0.85 or greater.

Chilkat C/C++ Library Downloads MS Visual C/C++ Libs

See Also: Using MFC CString in Chilkat

#include <CkPdf.h>
#include <CkJsonObject.h>
#include <CkCert.h>

void ChilkatSample(void)
    {
    CkString strOut;

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

    CkPdf pdf;

    // Load a PDF to be signed.
    // The "hello.pdf" is available at https://chilkatsoft.com/hello.pdf
    bool success = pdf.LoadFile("qa_data/pdf/hello.pdf");
    if (success == false) {
        strOut.append(pdf.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    // Options for signing are specified in JSON.
    CkJsonObject json;

    // In most cases, the signingCertificateV2 and signingTime attributes are required.
    json.UpdateInt("signingCertificateV2",1);
    json.UpdateInt("signingTime",1);

    // Tell Chilkat to create an LTV-enabled (long term validation) signature.
    // See PDF Long-Term Validation (LTV) Signature Example for more detailed comments about "ltvOcsp".
    json.UpdateBool("ltvOcsp",true);

    // Tell Chilkat to request a timestamp from a TSA server and include the timestamp token (1.2.840.113549.1.9.16.2.14)
    // in the CMS signature's authentication attributes
    json.UpdateBool("timestampToken.enabled",true);

    // In this example, we'll use a free TSA server (timestamp.digicert.com), but you may want to use your own timestamp authority server.
    json.UpdateString("timestampToken.tsaUrl","http://timestamp.digicert.com");

    // If the timestamp server requires a username/password, do the following.  Otherwise omit the following few lines of code.
    json.UpdateString("timestampToken.tsaUsername","the_tsa_username");
    json.UpdateString("timestampToken.tsaPassword","the_tsa_password");

    // When requesting the timestamp token, ask the server to include its certificate in the timestamp token response.
    // This allows for the timestamp server's certificate to be included in the LTV validation (i.e. if the timestamp server
    // has an OCSP URL, then Chilkat will also do the OCSP request for the timestamp server's certificate.)
    json.UpdateBool("timestampToken.requestTsaCert",true);

    // Define the appearance of the signature.
    json.UpdateInt("page",1);
    json.UpdateString("appearance.y","top");
    json.UpdateString("appearance.x","left");
    json.UpdateString("appearance.fontScale","10.0");
    json.UpdateString("appearance.text[0]","Digitally signed by: cert_cn");
    json.UpdateString("appearance.text[1]","current_dt");
    json.UpdateString("appearance.text[2]","This is an LTV-enabled signature with a TSA timestamp.");

    // Load the signing certificate. (Use your own certificate.)
    CkCert cert;
    success = cert.LoadPfxFile("qa_data/pfx/myPdfSigningCert.pfx","pfxPassword");
    if (success == false) {
        strOut.append(cert.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    // Tell the pdf object to use the certificate for signing.
    success = pdf.SetSigningCert(cert);
    if (success == false) {
        strOut.append(pdf.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    success = pdf.SignPdf(json,"qa_output/hello_ltv_signed_with_timestamp.pdf");
    if (success == false) {
        strOut.append(pdf.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    strOut.append("The PDF has been successfully cryptographically signed with TSA timestamp and long-term validation.");
    strOut.append("\r\n");

    // If you open the Signature Panel in Adobe Acrobat, it will indicate that the signature is LTV enabled
    // and contains an embedded timestamp:
    


    SetDlgItemText(IDC_EDIT1,strOut.getUnicode());

    }