(Visual FoxPro) IMAP Download and Verify Signed MIME

Downloads the unmodified MIME of a digitally signed email, saves the .p7s signature (and other MIME parts), then loads the email into a Chilkat email object (which unwraps the S/MIME and verifies the signature) and then saves attachments (if the MIME parts were not already saved).

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

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

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

* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.Imap')
loImap = CreateObject('Chilkat.Imap')

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

lnSuccess = loImap.Login("myLogin","myPassword")
IF (lnSuccess <> 1) THEN
    ? loImap.LastErrorText
    RELEASE loImap
    CANCEL
ENDIF

* Select an IMAP mailbox
lnSuccess = loImap.SelectMailbox("Inbox")
IF (lnSuccess <> 1) THEN
    ? loImap.LastErrorText
    RELEASE loImap
    CANCEL
ENDIF

* Download the 1st email (as MIME) in the Inbox by sequence number.
* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.StringBuilder')
loSbMime = CreateObject('Chilkat.StringBuilder')
lnSuccess = loImap.FetchSingleAsMimeSb(1,0,loSbMime)
IF (lnSuccess <> 1) THEN
    ? loImap.LastErrorText
    RELEASE loImap
    RELEASE loSbMime
    CANCEL
ENDIF

* Load it into a MIME object and check to see if it is signed
* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.Mime')
loMime = CreateObject('Chilkat.Mime')
loMime.LoadMimeSb(loSbMime)
lnAlreadySavedParts = 0
IF (loMime.ContainsSignedParts() = 1) THEN

    * This will save the .p7s and other parts...
    loSa = loMime.ExtractPartsToFiles("qa_output")
    IF (loMime.LastMethodSuccess = 1) THEN
        lnNumFiles = loSa.Count
        i = 0
        DO WHILE i < lnNumFiles
            ? "Created: " + loSa.GetString(i)
            i = i + 1
        ENDDO
        RELEASE loSa
        lnAlreadySavedParts = 1
    ENDIF

ENDIF

* Load the MIME into an Email object.  This unwraps the security layers and verifies signatures.
* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.Email')
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 = loEmail.GetSignedByCert()
        IF (loEmail.LastMethodSuccess <> 1) THEN
            ? "Failed to get signing certificate object."
        ELSE
            ? "Signing cert: " + loCert.SubjectCN
            RELEASE loCert
        ENDIF

    ENDIF

ELSE
    ? "Digital signature verification failed."
ENDIF

IF (lnAlreadySavedParts <> 1) THEN
    loEmail.SaveAllAttachments("qa_output")
ENDIF

RELEASE loImap
RELEASE loSbMime
RELEASE loMime
RELEASE loEmail