Lua Requires Chilkat v11.1.0+

openssl enc decrypt

See more Encryption Examples

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

Lua

local chilkat = require("chilkat")

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

local crypt = chilkat.Crypt2.new()

-- Use aes-256-cbc
crypt.crypt_algorithm = "aes"
crypt.cipher_mode = "cbc"
crypt.key_length = 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:
crypt.hash_algorithm = "sha256"

-- This example assumes openssl 1.0.2 was used to encrypt what we're now decrypting:
crypt.hash_algorithm = "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:
crypt:set_encoded_key("secret", "openssl")

-- Load the file to be decrypted.
local fileData = chilkat.BinData.new()
local success = fileData:load_file("qa_data/openssl_enc/hamlet.enc")

-- Decrypt
crypt.verbose_logging = true
success = crypt:decrypt_bd(fileData)
print(crypt.last_error_text)

-- Save the decrypted output.
success = fileData:write_file("c:/temp/qa_output/hamlet_dec.xml")

print("success = " .. tostring(success))