(Unicode C++) IMAP Download and Verify Signed (S/MIME) Email

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

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#include <CkImapW.h>
#include <CkMessageSetW.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.

    CkImapW imap;

    // Connect to an IMAP server.
    // Use TLS
    imap.put_Ssl(true);
    imap.put_Port(993);
    bool success = imap.Connect(L"imap.someMailServer.com");
    if (success != true) {
        wprintf(L"%s\n",imap.lastErrorText());
        return;
    }

    success = imap.Login(L"myLogin",L"myPassword");
    if (success != true) {
        wprintf(L"%s\n",imap.lastErrorText());
        return;
    }

    // Select an IMAP mailbox
    success = imap.SelectMailbox(L"Inbox");
    if (success != true) {
        wprintf(L"%s\n",imap.lastErrorText());
        return;
    }

    // We can choose to fetch UIDs or sequence numbers.
    bool fetchUids = true;

    // Get the message IDs of all the emails in the mailbox
    CkMessageSetW *messageSet = imap.Search(L"ALL",fetchUids);
    if (imap.get_LastMethodSuccess() != true) {
        wprintf(L"%s\n",imap.lastErrorText());
        return;
    }

    // Scan for emails with attachments, and save the attachments
    // to a sub-directory.
    int i = 0;
    while (i < messageSet->get_Count()) {

        const wchar_t *uid = messageSet->GetId(i);
        wprintf(L"uid: %s\n",uid);

        CkEmailW *email = imap.FetchSingle(uid,true);

        // 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 = email->GetSignedByCert();
                if (email->get_LastMethodSuccess() != true) {
                    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;
    }

    // Disconnect from the IMAP server.
    success = imap.Disconnect();

    delete messageSet;
    }