C

Sign PDF in the Cloud using AWS CloudHSM

See more Signing in the Cloud Examples

Demonstrates how to sign a PDF using AWS CloudHSM. The signing of the hash happens on a hardware token in AWS CloudHSM. Everything else involving the updating the PDF to add the signature happens locally within Chilkat.

Note: This example requires Chilkat v9.5.0.96 or greater.

C

#include <C_CkPkcs11.h>
#include <C_CkCert.h>
#include <C_CkPdf.h>
#include <C_CkJsonObject.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkPkcs11 pkcs11;
    const char *pin;
    int userType;
    HCkCert cert;
    HCkPdf pdf;
    HCkJsonObject json;
    int i;

    success = FALSE;

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

    // Note: Chilkat's PKCS11 implementation runs on Windows, Linux, Mac OS X, and other supported operating systems.

    pkcs11 = CkPkcs11_Create();

    // Provide the path to the AWS CloudHSM PKCS11 driver.
    // This example runs on Windows, so we'll provide the CloudHSM DLL.
    // If your code runs on Linux, the CloudHSM driver might be at /opt/cloudhsm/lib/libcloudhsm_pkcs11.so
    CkPkcs11_putSharedLibPath(pkcs11,"C:\\Program Files\\Amazon\\CloudHSM\\lib\\cloudhsm_pkcs11.dll");

    // Your PIN should be a string containing your crypto user's login and password, with a colon char delimiting.
    // See https://docs.aws.amazon.com/cloudhsm/latest/userguide/pkcs11-pin.html
    pin = "user:password";
    userType = 1;

    // Establish a PKCS logged-on session using the driver (.so, .dylib, or .dll) as specified in the SharedLibPath above.
    success = CkPkcs11_QuickSession(pkcs11,userType,pin);
    if (success == FALSE) {
        printf("%s\n",CkPkcs11_lastErrorText(pkcs11));
        CkPkcs11_Dispose(pkcs11);
        return;
    }

    cert = CkCert_Create();
    success = CkCert_LoadFromFile(cert,"qa_data/certs/myCert.cer");
    if (success == FALSE) {
        printf("%s\n",CkCert_lastErrorText(cert));
        CkPkcs11_Dispose(pkcs11);
        CkCert_Dispose(cert);
        return;
    }

    // Tell the certificate to link with the PKCS11 session.
    // The cert's private key should be installed on the CloudHSM.
    // If there are multiple private keys on the CloudHSM, then Chilkat will automatically
    // locate and use the private key corresponding to the certificate.
    success = CkCert_LinkPkcs11(cert,pkcs11);
    if (success == FALSE) {
        printf("%s\n",CkCert_lastErrorText(cert));
        CkPkcs11_Dispose(pkcs11);
        CkCert_Dispose(cert);
        return;
    }

    // --------------------------------------------------------------------------
    // At this point, we have the cert to be used for signing.
    // Our PDF signing code is the same as for a cert obtained from any other source..

    pdf = CkPdf_Create();

    // Load a PDF to be signed.
    success = CkPdf_LoadFile(pdf,"qa_data/pdf/hello.pdf");
    if (success == FALSE) {
        printf("%s\n",CkPdf_lastErrorText(pdf));
        success = CkPkcs11_CloseSession(pkcs11);
        CkPkcs11_Dispose(pkcs11);
        CkCert_Dispose(cert);
        CkPdf_Dispose(pdf);
        return;
    }

    json = CkJsonObject_Create();

    CkJsonObject_UpdateInt(json,"page",1);
    CkJsonObject_UpdateString(json,"appearance.y","top");
    CkJsonObject_UpdateString(json,"appearance.x","left");
    CkJsonObject_UpdateString(json,"appearance.fontScale","10.0");
    CkJsonObject_UpdateString(json,"signingAlgorithm","pss");
    CkJsonObject_UpdateString(json,"hashAlgorithm","sha256");

    i = 0;
    CkJsonObject_putI(json,i);
    CkJsonObject_UpdateString(json,"appearance.text[i]","Digitaly signed by: Xyz Widgets, Inc.");
    i = i + 1;
    CkJsonObject_putI(json,i);
    CkJsonObject_UpdateString(json,"appearance.text[i]","current_dt");
    i = i + 1;
    CkJsonObject_putI(json,i);
    CkJsonObject_UpdateString(json,"appearance.text[i]","blah blah blah");

    // The certificate is internally linked to the Pkcs11 object, which is currently in an authenticated session.
    success = CkPdf_SetSigningCert(pdf,cert);

    success = CkPdf_SignPdf(pdf,json,"qa_output/out.pdf");
    if (success == FALSE) {
        printf("%s\n",CkPdf_lastErrorText(pdf));
        success = CkPkcs11_CloseSession(pkcs11);
        CkPkcs11_Dispose(pkcs11);
        CkCert_Dispose(cert);
        CkPdf_Dispose(pdf);
        CkJsonObject_Dispose(json);
        return;
    }

    // --------------------------------------------------------------------------

    // Revert to an unauthenticated session by calling Logout.
    success = CkPkcs11_Logout(pkcs11);
    if (success == FALSE) {
        printf("%s\n",CkPkcs11_lastErrorText(pkcs11));
        success = CkPkcs11_CloseSession(pkcs11);
        CkPkcs11_Dispose(pkcs11);
        CkCert_Dispose(cert);
        CkPdf_Dispose(pdf);
        CkJsonObject_Dispose(json);
        return;
    }

    // When finished, close the session.
    // It is important to close the session (memory leaks will occur if the session is not properly closed).
    success = CkPkcs11_CloseSession(pkcs11);
    if (success == FALSE) {
        printf("%s\n",CkPkcs11_lastErrorText(pkcs11));
        CkPkcs11_Dispose(pkcs11);
        CkCert_Dispose(cert);
        CkPdf_Dispose(pdf);
        CkJsonObject_Dispose(json);
        return;
    }

    printf("Success.\n");


    CkPkcs11_Dispose(pkcs11);
    CkCert_Dispose(cert);
    CkPdf_Dispose(pdf);
    CkJsonObject_Dispose(json);

    }