AES256

Author: nsiatras

berry/encryption.php

@@ -1,4 +1,4 @@
 <?php
-
 require_once(__DIR__ . "/encryption/AES128Encryption.php");
+require_once(__DIR__ . "/encryption/AES256Encryption.php");
 ?>

berry/encryption/AES128Encryption.php

@@ -79,7 +79,7 @@ static function decrypt(string $key, string $data)
     {
         if (strlen($key) < AES128Encryption::$CIPHER_KEY_LEN)
         {
-            $key = str_pad("$key", AES128Encryption::$CIPHER_KEY_LEN, "0"); //0 pad to len 16
+            $key = str_pad($key, AES128Encryption::$CIPHER_KEY_LEN, "0"); //0 pad to len 16
         }
         else if (strlen($key) > AES128Encryption::$CIPHER_KEY_LEN)
         {

berry/encryption/AES256Encryption.php

@@ -0,0 +1,96 @@
+<?php
+
+/*
+  MIT License
+
+  Copyright (c) 2022 Nikos Siatras
+
+  Permission is hereby granted, free of charge, to any person obtaining a copy
+  of this software and associated documentation files (the "Software"), to deal
+  in the Software without restriction, including without limitation the rights
+  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+  copies of the Software, and to permit persons to whom the Software is
+  furnished to do so, subject to the following conditions:
+
+  The above copyright notice and this permission notice shall be included in all
+  copies or substantial portions of the Software.
+
+  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+  SOFTWARE.
+ */
+
+class AES256Encryption
+{
+
+    private static string $OPENSSL_CIPHER_NAME = "aes-256-cbc"; //Name of OpenSSL Cipher 
+    private static int $CIPHER_KEY_LEN = 32; // 32 bytes (256 bits)
+
+    static function getRandomIV()
+    {
+        $length = 16;
+        $characters = '0123456789abcdefghijklmnopqrstuvwxyz!@#$%^&*()-=_+ABCDEFGHIJKLMNOPQRSTUVWXYZ';
+        $charactersLength = strlen($characters);
+        $randomString = '';
+        for ($i = 0; $i < $length; $i++)
+        {
+            $randomString .= $characters[rand(0, $charactersLength - 1)];
+        }
+
+        return $randomString;
+    }
+
+    /**
+
+     * Encrypt data using AES Cipher (CBC) with 256 bit key
+     * @param type $key - key to use should be 32 bytes long (256 bits)
+     * @param type $data - data to encrypt
+     * @return encrypted data in base64 encoding with iv attached at end after a :
+     */
+    static function encrypt(string $key, string $data)
+    {
+        $iv = AES256Encryption::getRandomIV();
+
+        if (strlen($key) < AES256Encryption::$CIPHER_KEY_LEN)
+        {
+            $key = str_pad($key, AES256Encryption::$CIPHER_KEY_LEN, "0"); //0 pad to len 32
+        }
+        else if (strlen($key) > AES256Encryption::$CIPHER_KEY_LEN)
+        {
+            $key = substr($str, 0, AES256Encryption::$CIPHER_KEY_LEN); //truncate to 32 bytes
+        }
+
+        $encodedEncryptedData = base64_encode(openssl_encrypt($data, AES256Encryption::$OPENSSL_CIPHER_NAME, $key, OPENSSL_RAW_DATA, $iv));
+        $encodedIV = base64_encode($iv);
+        $encryptedPayload = $encodedEncryptedData . ":" . $encodedIV;
+        return $encryptedPayload;
+    }
+
+    /**
+     * Decrypt data using AES Cipher (CBC) with 256 bit key
+     * @param type $key - key to use should be 32 bytes long (256 bits)
+     * @param type $data - data to be decrypted in base64 encoding with iv attached at the end after a :
+     * @return decrypted data
+     */
+    static function decrypt(string $key, string $data)
+    {
+        if (strlen($key) < AES256Encryption::$CIPHER_KEY_LEN)
+        {
+            $key = str_pad($key, AES256Encryption::$CIPHER_KEY_LEN, "0"); //0 pad to len 32
+        }
+        else if (strlen($key) > AES256Encryption::$CIPHER_KEY_LEN)
+        {
+            $key = substr($str, 0, AES256Encryption::$CIPHER_KEY_LEN); //truncate to 32 bytes
+        }
+
+        $parts = explode(':', $data); //Separate Encrypted data from iv.
+        $decryptedData = openssl_decrypt(base64_decode($parts[0]), AES256Encryption::$OPENSSL_CIPHER_NAME, $key, OPENSSL_RAW_DATA, base64_decode($parts[1]));
+        return $decryptedData;
+    }
+}
+
+?>