Use a PFX TLS Client Certificate

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Demonstrates the Chilkat MailMan.SetSslClientCertPfx method, which sets the client-side certificate for SSL/TLS connections, loading it from a PFX/PKCS#12 file. The first argument is the path to the PFX file and the second is its password. This example loads a client certificate directly from a PFX.

Background: This is the convenience form of SetSslClientCert: rather than loading a Cert object first, you point straight at the PFX file and password. A PFX (PKCS#12) bundles the certificate with its private key — exactly what mutual TLS requires, since the client must prove possession of the key during the handshake. It is the usual client-credential format on Windows.

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#include <C_CkMailMan.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkMailMan mailman;

    success = FALSE;

    //  Demonstrates the MailMan.SetSslClientCertPfx method, which sets the client-side
    //  certificate for SSL/TLS connections, loading it from a PFX/PKCS#12 file.  The 1st argument
    //  is the PFX path and the 2nd is the PFX password.

    mailman = CkMailMan_Create();

    //  Configure the SMTP server connection.
    CkMailMan_putSmtpHost(mailman,"smtp.example.com");
    CkMailMan_putSmtpPort(mailman,465);
    CkMailMan_putSmtpSsl(mailman,TRUE);
    CkMailMan_putSmtpUsername(mailman,"user@example.com");
    CkMailMan_putSmtpPassword(mailman,"myPassword");

    //  Load the client certificate directly from a PFX file.
    success = CkMailMan_SetSslClientCertPfx(mailman,"qa_data/certs/client.pfx","pfx_password");
    if (success == FALSE) {
        printf("%s\n",CkMailMan_lastErrorText(mailman));
        CkMailMan_Dispose(mailman);
        return;
    }

    success = CkMailMan_VerifySmtpLogin(mailman);
    if (success == FALSE) {
        printf("%s\n",CkMailMan_lastErrorText(mailman));
        CkMailMan_Dispose(mailman);
        return;
    }

    printf("Connected using a PFX TLS client certificate.\n");

    //  Note: The path "qa_data/certs/client.pfx" is a relative local filesystem path,
    //  relative to the current working directory of the running application.


    CkMailMan_Dispose(mailman);

    }