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Unicode C

Send Signed Email using PFX File (long version)

Demonstrates how to send a signed email using a digital certificate w/ private key stored in a PFX file.

Chilkat Unicode C Downloads

Unicode C
#include <C_CkMailManW.h>
#include <C_CkEmailW.h>
#include <C_CkCertStoreW.h>
#include <C_CkJsonObjectW.h>
#include <C_CkCertW.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkMailManW mailman;
    HCkEmailW email;
    HCkCertStoreW certStore;
    HCkJsonObjectW jsonE;
    HCkCertW cert;
    HCkCertW cert2;

    success = FALSE;

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

    // The mailman object is used for sending and receiving email.
    mailman = CkMailManW_Create();

    // Set the SMTP server.
    CkMailManW_putSmtpHost(mailman,L"smtp.mymailserver.com");

    // Create a new email object
    email = CkEmailW_Create();

    CkEmailW_putSubject(email,L"This email is signed");
    CkEmailW_putBody(email,L"This is a digitally signed mail");
    CkEmailW_putFrom(email,L"Chilkat Admin <admin@chilkatsoft.com>");
    success = CkEmailW_AddTo(email,L"Chilkat Support",L"support@chilkatsoft.com");

    // Indicate that the email should be sent signed.
    CkEmailW_putSendSigned(email,TRUE);

    // Load a PFX file into a certificate store object.
    // Then locate the certificate matching the  sender's email address,
    // and use it for signing.
    // (a PFX file may contain more than one certificate.)
    certStore = CkCertStoreW_Create();
    // The 1st argument is the path of the PFX file, the 2nd arg is the 
    // PFX file's password:
    success = CkCertStoreW_LoadPfxFile(certStore,L"/pfx_files/chilkatsoft_secret.pfx",L"secret");
    if (success != TRUE) {
        wprintf(L"%s\n",CkCertStoreW_lastErrorText(certStore));
        CkMailManW_Dispose(mailman);
        CkEmailW_Dispose(email);
        CkCertStoreW_Dispose(certStore);
        return;
    }

    // Find the certificate for the email address:
    jsonE = CkJsonObjectW_Create();
    CkJsonObjectW_UpdateString(jsonE,L"email",L"admin@chilkatsoft.com");

    cert = CkCertW_Create();
    success = CkCertStoreW_FindCert(certStore,jsonE,cert);
    if (success == FALSE) {
        wprintf(L"%s\n",CkCertStoreW_lastErrorText(certStore));
        CkMailManW_Dispose(mailman);
        CkEmailW_Dispose(email);
        CkCertStoreW_Dispose(certStore);
        CkJsonObjectW_Dispose(jsonE);
        CkCertW_Dispose(cert);
        return;
    }

    // Alternatively, if a PFX file is known to contain a single certificate,
    // you may load it directly into a Chilkat certificate object.
    // This snippet of source code shows how:
    cert2 = CkCertW_Create();
    // The 1st argument is the filename, the 2nd arg is the 
    // PFX file's password:
    success = CkCertW_LoadPfxFile(cert2,L"/pfx_files/chilkatsoft_secret.pfx",L"secret");
    if (success != TRUE) {
        wprintf(L"%s\n",CkCertW_lastErrorText(cert2));
        CkMailManW_Dispose(mailman);
        CkEmailW_Dispose(email);
        CkCertStoreW_Dispose(certStore);
        CkJsonObjectW_Dispose(jsonE);
        CkCertW_Dispose(cert);
        CkCertW_Dispose(cert2);
        return;
    }

    // This example will use the cert from the certStore...
    success = CkEmailW_SetSigningCert(email,cert);

    // Signed email can be sent in two different ways.  
    // In a multipart/signed email, the signature is attached as a separate MIME part.
    // In an opaque email (signedData) the content of the email is encapsulated within the signature
    // and the email is sent as "application/pkcs7-mime". 
    // Either should be fine, but some receiving systems might require one or the other..
    CkMailManW_putOpaqueSigning(mailman,FALSE);

    // Send a signed email.
    success = CkMailManW_SendEmail(mailman,email);
    if (success != TRUE) {
        wprintf(L"%s\n",CkMailManW_lastErrorText(mailman));
    }
    else {
        // The LastErrorText property provides information
        // even when successful.
        wprintf(L"%s\n",CkMailManW_lastErrorText(mailman));
        wprintf(L"Mail Sent!\n");
    }



    CkMailManW_Dispose(mailman);
    CkEmailW_Dispose(email);
    CkCertStoreW_Dispose(certStore);
    CkJsonObjectW_Dispose(jsonE);
    CkCertW_Dispose(cert);
    CkCertW_Dispose(cert2);

    }