(Perl) 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 Perl Downloads Perl Module for Windows, MacOS, Linux, Alpine Linux, Solaris

use chilkat();

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

$crypt = chilkat::CkCrypt2->new();

# Use aes-256-cbc
$crypt->put_CryptAlgorithm("aes");
$crypt->put_CipherMode("cbc");
$crypt->put_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:
$crypt->put_HashAlgorithm("sha256");

# This example assumes openssl 1.0.2 was used to encrypt what we're now decrypting:
$crypt->put_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:
$crypt->SetSecretKeyViaPassword("secret");

# Load the file to be decrypted.
$fileData = chilkat::CkBinData->new();
$success = $fileData->LoadFile("qa_data/openssl_enc/hamlet.enc");

# Decrypt
$success = $crypt->DecryptBd($fileData);

# Save the decrypted output.
$success = $fileData->WriteFile("qa_output/hamlet_dec.xml");

print "success = " . $success . "\r\n";