OpenSSL encryption example with AES-256-CBC

openssl.php

<?php

$privateKey = 'someprivatekey';
$secretInfo = 'secretInfo';
$method = 'aes-256-cbc';

$ivLength = openssl_cipher_iv_length($method);
$iv = random_bytes($ivLength);

$encryptedData = openssl_encrypt($secretInfo, $method, $privateKey, OPENSSL_RAW_DATA, $iv);

$token = base64_encode($iv . $encryptedData);
echo "Encrypted token: " . $token . "\n";


$data = base64_decode($token);
$ivLength = openssl_cipher_iv_length($method);
$iv = substr($data, 0, $ivLength);
$encryptedData = substr($data, $ivLength);
$decrypted = openssl_decrypt($encryptedData, $method, $privateKey, OPENSSL_RAW_DATA, $iv);

echo $decrypted;