(PHP Extension) AES OFB Output Feedback Mode Encryption

Demonstrates how to encrypt using AES OFB (Output Feedback) mode.

Chilkat PHP Downloads PHP Extension for Windows, Linux, MacOS, Alpine Linux, Solaris

<?php

// The version number (9_5_0) should match version of the Chilkat extension used, omitting the micro-version number.
// For example, if using Chilkat v9.5.0.48, then include as shown here:
include("chilkat_9_5_0.php");

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

$crypt = new CkCrypt2();

$crypt->put_CryptAlgorithm('aes');
// Set the cipher mode to Output Feedback
$crypt->put_CipherMode('ofb');
$crypt->put_KeyLength(256);

// EncodingMode specifies the encoding of the output for
// encryption, and the input for decryption.
// It may be "hex", "url", "base64", "quoted-printable", or many other choices.
$crypt->put_EncodingMode('hex');

$ivHex = '000102030405060708090A0B0C0D0E0F';
$crypt->SetEncodedIV($ivHex,'hex');

// The secret key must equal the size of the key.  For
// 256-bit encryption, the binary secret key is 32 bytes.
$keyHex = '603deb1015ca71be2b73aef0857d77811f352c073b6108d72d9810a30914dff4';
$crypt->SetEncodedKey($keyHex,'hex');

// Encrypt a string...
$encStr = $crypt->encryptStringENC('Popular opinions, on subjects not palpable to sense, are often true, but seldom or never the whole truth. -- John Stuart Mill');
print $encStr . "\n";

$decrypt = new CkCrypt2();
$decrypt->put_CryptAlgorithm('aes');
$decrypt->put_CipherMode('ofb');
$decrypt->put_KeyLength(256);
$decrypt->put_EncodingMode('hex');
$decrypt->SetEncodedIV($ivHex,'hex');
$decrypt->SetEncodedKey($keyHex,'hex');

// Now decrypt:
$decStr = $decrypt->decryptStringENC($encStr);
print $decStr . "\n";

?>