(Visual FoxPro) IMAP Download and Verify Signed MIME

Downloads the original MIME of a digitally signed email and saves the .p7s signature along with other MIME parts. It then imports the email into a Chilkat email object to unwrap the S/MIME and verify the signature, and subsequently saves the attachments if they haven't been saved already.

Note: This example requires Chilkat v11.0.0 or greater.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

LOCAL lnSuccess
LOCAL loImap
LOCAL loSbMime
LOCAL loMime
LOCAL lnAlreadySavedParts
LOCAL loSt
LOCAL lnNumFiles
LOCAL i
LOCAL loEmail
LOCAL loCert

lnSuccess = 0

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

loImap = CreateObject('Chilkat.Imap')

* Connect to an IMAP server.
* Use TLS
loImap.Ssl = 1
loImap.Port = 993
lnSuccess = loImap.Connect("imap.example.com")
IF (lnSuccess = 0) THEN
    ? loImap.LastErrorText
    RELEASE loImap
    CANCEL
ENDIF

lnSuccess = loImap.Login("myLogin","myPassword")
IF (lnSuccess = 0) THEN
    ? loImap.LastErrorText
    RELEASE loImap
    CANCEL
ENDIF

* Select an IMAP mailbox
lnSuccess = loImap.SelectMailbox("Inbox")
IF (lnSuccess = 0) THEN
    ? loImap.LastErrorText
    RELEASE loImap
    CANCEL
ENDIF

* Download the 1st email (as MIME) in the Inbox by sequence number.
loSbMime = CreateObject('Chilkat.StringBuilder')
lnSuccess = loImap.FetchSingleAsMimeSb(1,0,loSbMime)
IF (lnSuccess = 0) THEN
    ? loImap.LastErrorText
    RELEASE loImap
    RELEASE loSbMime
    CANCEL
ENDIF

* Load it into a MIME object and check to see if it is signed
loMime = CreateObject('Chilkat.Mime')
loMime.LoadMimeSb(loSbMime)
lnAlreadySavedParts = 0
IF (loMime.ContainsSignedParts() = 1) THEN

    * This will save the .p7s and other parts...
    loSt = CreateObject('Chilkat.StringTable')
    lnSuccess = loMime.PartsToFiles("c:/temp/qa_output",loSt)
    IF (lnSuccess = 1) THEN
        lnNumFiles = loSt.Count
        i = 0
        DO WHILE i < lnNumFiles
            ? "Created: " + loSt.StringAt(i)
            i = i + 1
        ENDDO
        lnAlreadySavedParts = 1
    ENDIF

ENDIF

* Load the MIME into an Email object.  This unwraps the security layers and verifies signatures.
loEmail = CreateObject('Chilkat.Email')
loEmail.SetFromMimeSb(loSbMime)

IF (loEmail.ReceivedSigned = 1) THEN

    ? "This email was signed."

    * Check to see if the signatures were verified.
    IF (loEmail.SignaturesValid = 1) THEN
        ? "Digital signature(s) verified."

        ? "Signer: " + loEmail.SignedBy

        * The certificate used for signing may be obtained
        * by calling email.GetSignedByCert.
        loCert = CreateObject('Chilkat.Cert')
        lnSuccess = loEmail.LastSignerCert(i,loCert)
        IF (lnSuccess = 0) THEN
            ? "Failed to get signing certificate object."
        ELSE
            ? "Signing cert: " + loCert.SubjectCN
        ENDIF

    ENDIF

ELSE
    ? "Digital signature verification failed."
ENDIF

IF (lnAlreadySavedParts <> 1) THEN
    loEmail.SaveAllAttachments("c:/temp/qa_output")
ENDIF

RELEASE loImap
RELEASE loSbMime
RELEASE loMime
RELEASE loSt
RELEASE loEmail
RELEASE loCert