(PHP Extension) Manually Duplicate SetSecretKeyViaPassword

Demonstrates how to duplicate the password string to binary secret key computation of SetSecretKeyViaPassword.

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

$crypt = new CkCrypt2();

// The password string is transformed to a binary secret key by computing the 
// MD5 digest (of the utf-8 password) to obtain 16 bytes.  
// If the KeyLength is greater than 16 bytes, then the MD5 digest of the Base64 encoding 
// of the utf-8 password is added.  A max of 32 bytes of key material is generated, and 
// this is truncated to the actual KeyLength required.

$crypt->put_CryptAlgorithm('aes');
$crypt->put_KeyLength(256);

$password = 'this is my password';
$crypt->SetSecretKeyViaPassword($password);

// Examine the resulting SecretKey in hex:
print 'Computed Secret Key = ' . $crypt->getEncodedKey('hex') . "\n";

// Now perform the same computation manually:
$sb = new CkStringBuilder();

$crypt->put_HashAlgorithm('md5');
$crypt->put_Charset('utf-8');
$crypt->put_EncodingMode('hex');
$sb->Append($crypt->hashStringENC($password));

$passwordBase64 = $crypt->encodeString($password,'utf-8','base64');
$sb->Append($crypt->hashStringENC($passwordBase64));

print 'Manually Computed = ' . $sb->getAsString() . "\n";

// The output is:
// Computed Secret Key = 210D53992DFF432EC1B1A9698AF9DA16C7E90518F90E24828F78EC9E0A413B36
// Manually Computed = 210D53992DFF432EC1B1A9698AF9DA16C7E90518F90E24828F78EC9E0A413B36

?>