(Visual FoxPro) openssl enc decrypt

Demonstrates how to decrypt a file that was encrypted using "openssl enc".

This example shows how to decrypt what was created using this openssl command:

openssl enc -e -aes-256-cbc -in hamlet.xml -out hamlet.enc -pass file:./secret.txt

This example shows how to do this:

openssl enc -d -aes-256-cbc -in hamlet.enc -out hamlet_dec.xml -pass file:./secret.txt

Note: This example requires Chilkat v9.5.0.71 or later.

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

LOCAL loCrypt
LOCAL loFileData
LOCAL lnSuccess

* 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.Crypt2')
loCrypt = CreateObject('Chilkat.Crypt2')

* Use aes-256-cbc
loCrypt.CryptAlgorithm = "aes"
loCrypt.CipherMode = "cbc"
loCrypt.KeyLength = 256

* We'll need to set the hash algorithm to either MD5 or SHA256.
* openssl version 1.0.* or earlier used MD5 by default
* openssl version 1.1.* uses SHA-256 for the password to secret key derivation.

* For example, if openssl 1.1.0 was used, we should do this:
loCrypt.HashAlgorithm = "sha256"

* This example assumes openssl 1.0.2 was used to encrypt what we're now decrypting:
loCrypt.HashAlgorithm = "md5"

* The openssl command we are duplicating is:
* 
*    openssl enc -d -aes-256-cbc -in hamlet.enc -out hamlet_dec.xml -pass file:./secret.txt
* 
* The file secret.txt contains the word "secret".  We could write code to load the contents
* of secret.txt, but instead we'll just do this:
loCrypt.SetSecretKeyViaPassword("secret")

* Load the file to be decrypted.
* For versions of Chilkat < 10.0.0, use CreateObject('Chilkat_9_5_0.BinData')
loFileData = CreateObject('Chilkat.BinData')
lnSuccess = loFileData.LoadFile("qa_data/openssl_enc/hamlet.enc")

* Decrypt
lnSuccess = loCrypt.DecryptBd(loFileData)

* Save the decrypted output.
lnSuccess = loFileData.WriteFile("qa_output/hamlet_dec.xml")

? "success = " + STR(lnSuccess)

RELEASE loCrypt
RELEASE loFileData