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Decrypt S/MIME with an Explicit Certificate and Private Key

Loads a CMS/PKCS #7 encrypted S/MIME message and decrypts it back to the original MIME content.

Decrypt2 accepts the certificate and its private key directly as arguments.

The file paths are relative to the application's current working directory. Absolute paths may also be used. Supply the paths appropriate to your own environment.

Background. When the certificate and private key are already loaded as separate objects, Decrypt2 uses them directly rather than searching an internal collection of credential sources.

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Local $bSuccess = False

$oMime = ObjCreate("Chilkat.Mime")
$bSuccess = $oMime.LoadMimeFile("qa_data/encrypted.eml")
If ($bSuccess = False) Then
    ConsoleWrite($oMime.LastErrorText & @CRLF)
    Exit
EndIf

;  Decrypt using an explicitly supplied certificate and private key.  The 1st argument is the
;  certificate and the 2nd is its private key.
$oCert = ObjCreate("Chilkat.Cert")
$bSuccess = $oCert.LoadFromFile("qa_data/recipient.cer")
If ($bSuccess = False) Then
    ConsoleWrite($oCert.LastErrorText & @CRLF)
    Exit
EndIf

$oPrivKey = ObjCreate("Chilkat.PrivateKey")
$bSuccess = $oPrivKey.LoadPemFile("qa_data/recipient_privkey.pem")
If ($bSuccess = False) Then
    ConsoleWrite($oPrivKey.LastErrorText & @CRLF)
    Exit
EndIf

$bSuccess = $oMime.Decrypt2($oCert,$oPrivKey)
If ($bSuccess = False) Then
    ConsoleWrite($oMime.LastErrorText & @CRLF)
    Exit
EndIf

Local $sBody = $oMime.GetBodyDecoded()
If ($oMime.LastMethodSuccess = False) Then
    ConsoleWrite($oMime.LastErrorText & @CRLF)
    Exit
EndIf

ConsoleWrite($sBody & @CRLF)