(AutoIt) Encrypt File to PKCS7 .p7m

AutoIt example to public-key encrypt a file creating a PKCS#7 .p7m file as output. Also demonstrates how to decrypt the .p7m to recover the original file.

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

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

$oCrypt = ObjCreate("Chilkat.Crypt2")

; Indicate the public-key encryption is to be used.
; Do this by setting the encryption algorithm equal 
; to "PKI" (an acroynm for public-key infrastructure).
$oCrypt.CryptAlgorithm = "PKI"

; Indicate the inner symmetric encryption algorithm to be used.
; possible values are "aes", "des", "3des", and "rc2".
; For this example, we'll use 256-bit AES encryption.
$oCrypt.Pkcs7CryptAlg = "aes"
$oCrypt.KeyLength = 256

; To encrypt, only a certificate w/ public key is needed.
; (The certificate w/ private key is required for decryption.)

; The LoadFromFile method can load virtually any certificate format:
; 1. DER encoded binary X.509 (.CER)
; 2. Base-64 encoded X.509 (.CER)
; 3. Cryptographic Message Syntax Standard - PKCS #7 Certificates (.P7B)
; 4. PEM format
$oEncryptCert = ObjCreate("Chilkat.Cert")
Local $bSuccess = $oEncryptCert.LoadFromFile("/Users/chilkat/testData/cer/acme.cer")
If ($bSuccess <> True) Then
    ConsoleWrite($oEncryptCert.LastErrorText & @CRLF)
    Exit
EndIf

; Tell the crypt object to use the certificate for encrypting:
$oCrypt.AddEncryptCert $oEncryptCert

; Encrypt a file, producing a .p7m as output.
; The input file is unchanged, the output .p7m contains the encrypted
; contents of the input file.
Local $sInFile = "/Users/chilkat/testData/pdf/sample.pdf"
Local $sOutFile = "/Users/chilkat/testData/p7m/sample.pdf.p7m"
$bSuccess = $oCrypt.CkEncryptFile($sInFile,$sOutFile)
If ($bSuccess <> True) Then
    ConsoleWrite($oCrypt.LastErrorText & @CRLF)
    Exit
EndIf

; For demonstration purposes, a different instance of the object will be used
; for decryption.
$oDecrypt = ObjCreate("Chilkat.Crypt2")

; To decrypt, the certificate w/ private key is required.  A PFX (also known
; as PKCS#12) is a common secure container for certs and private keys.
Local $sPfxFilename = "/Users/chilkat/testData/pfx/acme.pfx"
Local $sPfxPassword = "secret"

; Tell the component to look in the PFX file for certs and private keys.
$bSuccess = $oDecrypt.AddPfxSourceFile($sPfxFilename,$sPfxPassword)
If ($bSuccess <> True) Then
    ConsoleWrite($oDecrypt.LastErrorText & @CRLF)
    Exit
EndIf

; Tell the decrypt object that PKI (public key encryption) is to be used
; for decryptiong.
$oDecrypt.CryptAlgorithm = "PKI"
; There is no need to set the Pkcs7Alg or KeyLength because this information
; is contained within the .p7m

; Decrypt the .p7m
$sInFile = "/Users/chilkat/testData/p7m/sample.pdf.p7m"
$sOutFile = "/Users/chilkat/testData/pdf/recovered.pdf"
$bSuccess = $oDecrypt.CkDecryptFile($sInFile,$sOutFile)
If ($bSuccess = False) Then
    ConsoleWrite($oDecrypt.LastErrorText & @CRLF)
    Exit
EndIf

ConsoleWrite("Success!" & @CRLF)