(Unicode C++) POP3 Verify Signed (S/MIME) Email

Demonstrates how to download and verify digitally signed S/MIME email.

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#include <CkMailManW.h>
#include <CkStringArrayW.h>
#include <CkEmailW.h>
#include <CkCertW.h>

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

    CkMailManW mailman;
    bool success;

    // Set the POP3 server's hostname
    mailman.put_MailHost(L"pop.someMailServer.com");

    // Set the POP3 login/password.
    mailman.put_PopUsername(L"myLogin");
    mailman.put_PopPassword(L"myPassword");

    CkStringArrayW *sa = mailman.GetUidls();
    if (mailman.get_LastMethodSuccess() == false) {
        wprintf(L"%s\n",mailman.lastErrorText());
        return;
    }

    CkEmailW *email = 0;
    const wchar_t *uidl = 0;

    int i = 0;
    while (i < sa->get_Count()) {

        uidl = sa->getString(i);

        email = mailman.FetchEmail(uidl);
        if (mailman.get_LastMethodSuccess() == false) {
            wprintf(L"%s\n",mailman.lastErrorText());
            delete sa;
            return;
        }

        wprintf(L"%s\n",email->ck_from());
        wprintf(L"%s\n",email->subject());

        // The security layers of signed and/or encrypted emails
        // are automatically "unwrapped" when loaded into
        // a Chilkat email object.
        // An application only needs to check to see if an email
        // was received signed or encrypted, and then examine
        // the success/failure.  For example:
        if (email->get_ReceivedSigned() == true) {

            wprintf(L"This email was signed.\n");

            // Check to see if the signatures were verified.
            if (email->get_SignaturesValid() == true) {
                wprintf(L"Digital signature(s) verified.\n");
                wprintf(L"Signer: %s\n",email->signedBy());

                // The certificate used for signing may be obtained
                // by calling email.GetSignedByCert.
                CkCertW *cert = 0;
                cert = email->GetSignedByCert();
                if (email->get_LastMethodSuccess() == false) {
                    wprintf(L"Failed to get signing certificate object.\n");
                }
                else {
                    wprintf(L"Signing cert: %s\n",cert->subjectCN());
                    delete cert;
                }

            }
            else {
                wprintf(L"Digital signature verification failed.\n");
            }

        }

        delete email;
        i = i + 1;
    }

    delete sa;

    mailman.Pop3EndSession();
    }