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Decrypt S/MIME and Verify S/MIME Signatures

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_LANGUAGE_ example to decrypt S/MIME and verify S/MIME signatures. The S/MIME is unwrapped to get the original MIME prior to signing/encrypting. AutoIt

Local $bSuccess = False

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

$oMime = ObjCreate("Chilkat.Mime")

; Load an S/MIME message from a file:
$bSuccess = $oMime.LoadMimeFile("signedMime.txt")
If ($bSuccess = False) Then
    ConsoleWrite($oMime.LastErrorText & @CRLF)
    Exit
EndIf

; The ContainsEncryptedParts/ContainsSignedParts methods
; can be called to determine if the MIME is encrypted and/or signed:
Local $bIsEncrypted = $oMime.ContainsEncryptedParts()
Local $bIsSigned = $oMime.ContainsSignedParts()

; We don't want the "unwrap extras".  You'll see what those
; are in a few moments...
$oMime.UnwrapExtras = False

; To verify the signature, call UnwrapSecurity.  This will
; verify the signature(s) and decrypt the S/MIME and restore
; the MIME to the unsigned/unencrypted state.
; The results of what was found are present in the MIME object's
; properties, as well as extra header fields that are added
; to the unwrapped MIME.
$bSuccess = $oMime.UnwrapSecurity()
If ($bSuccess <> True) Then
    ; UnwrapSecurity returns True if all signatures were
    ; verified and all parts decrypted.
    ConsoleWrite($oMime.LastErrorText & @CRLF)
    Exit
EndIf

; The mime.UnwrapExtras property controls whether or not
; these additional fields are added to the unwrapped MIME:
; 
; X-NumPartsSigned: 1
; X-SignaturesValid: yes
; X-NumPartsEncrypted: 1
; X-Decrypted: no
; 
; The X-NumPartsSigned/X-SignaturesValid headers are added
; if the MIME was signed.  
; 
; The X-NumPartsEncrypted/X-Decrypted headers are added
; if the MIME was encrypted.
; 

; If the MIME was signed, get the certificate used for signing.
If ($bIsSigned = True) Then
    $oSignerCert = ObjCreate("Chilkat.Cert")

    ; The NumSignerCerts property indicates how many certificates
    ; were used for signing.  This example will assume the value is 1.
    ; To get the 1st signer cert, call LastSignerCert with an index of 0:
    $bSuccess = $oMime.LastSignerCert(0,$oSignerCert)
    If ($bSuccess = True) Then
        ConsoleWrite("**** Signer Cert: " & $oSignerCert.SubjectCN & @CRLF)
    EndIf

EndIf

; If the MIME was encrypted, get the certificate used for decryption
If ($bIsEncrypted = True) Then
    ; The NumDecryptCerts property indicates how many certificates
    ; were used for decrypting.  This example will assume the value is 1.
    ; To get the 1st decrypt cert, call LastDecryptCert with an index of 0:
    $oDecryptCert = ObjCreate("Chilkat.Cert")
    $bSuccess = $oMime.LastDecryptCert(0,$oDecryptCert)
    If ($bSuccess = True) Then
        ConsoleWrite("**** Decrypt Cert: " & $oDecryptCert.SubjectCN & @CRLF)
    EndIf

EndIf

; Display the unwrapped MIME:
ConsoleWrite($oMime.GetMime() & @CRLF)

; Save the unwrapped MIME to a file:
$bSuccess = $oMime.SaveMime("unwrappedMime.txt")