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@phpguru phpguru/Crypt.php forked from dfreerksen/Crypt.php
Created Mar 18, 2014

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<?php
class Crypt {
/**
* The encryption cipher
*
* @var string
*/
static public $cipher = MCRYPT_RIJNDAEL_256;
/**
* The encryption mode
*
* @var string
*/
static public $mode = MCRYPT_MODE_CBC;
/**
* The block size of the cipher
*
* @var int
*/
static public $block = 24;
/**
* Default hash algorithm
*
* @var string
*/
static public $algo = 'sha256';
/**
* Salt key
*
* @var string
*/
static public $key = '';
/**
* Set salt key
*
* @param string $key
*/
static public function key($key = '') {
if ( ! empty($key) && is_string($key)) {
self::$key = $key;
}
}
/**
* Encrypt a string using the AES-256 scheme and base64 (URL safe) encoded
*
* @param string $value
* @param string $key
* @return string
*/
static public function encrypt($value = '', $key = NULL) {
$iv = mcrypt_create_iv(self::_ivSize(), self::_randomizer());
$value = self::_pad($value);
$value = mcrypt_encrypt(self::$cipher, self::_key($key), $value, self::$mode, $iv);
return self::_b64encodeSafe($iv.$value);
}
/**
* Decrypt a string
*
* @param string $value
* @param string $key
* @return string
*/
static public function decrypt($value = '', $key = NULL) {
$value = self::_b64decodeSafe($value);
// Extract the input vector and the encrypted value
$iv = substr($value, 0, self::_ivSize());
$value = substr($value, self::_ivSize());
$key = self::_key($key);
$value = mcrypt_decrypt(self::$cipher, $key, $value, self::$mode, $iv);
return self::_unpad($value);
}
/**
* General hashing of a string
*
* @param string $data
* @param string $algo
* @param bool $raw_output
* @return string
*/
static public function hash($data = '', $algo = '', $raw_output = false) {
// Algorithm
$algo = self::_algo($algo);
return hash($algo, $data, (bool) $raw_output);
}
/**
* Determine if an unhashed value matches a hashed value
*
* @param string $data
* @param string $hash
* @param string $algo
* @return bool
*/
static public function check($data = '', $hash = '', $algo = '') {
$algo = self::_algo($algo);
return self::hash($data, $algo) === $hash;
}
/**
* Get the most secure random number generator for the system
*
* @return int
*/
static private function _randomizer() {
if (defined('MCRYPT_DEV_URANDOM')) {
return MCRYPT_DEV_URANDOM;
}
elseif (defined('MCRYPT_DEV_RANDOM')) {
return MCRYPT_DEV_RANDOM;
}
else {
mt_srand();
return MCRYPT_RAND;
}
}
/**
* Get the input vector size for the cipher and mode
*
* @return int
*/
static private function _ivSize() {
return mcrypt_get_iv_size(self::$cipher, self::$mode);
}
/**
* Add compatible padding on the given value
*
* @param string $value
* @return string
*/
static private function _pad($value) {
$block = self::_block();
$pad = $block - (self::_length($value) % $block);
$value .= str_repeat(chr($pad), $pad);
return $value;
}
/**
* Remove the compatible padding from the given value
*
* @param string $value
* @return string
* @throws Exception
*/
static private function _unpad($value = '') {
$block = self::_block();
$pad = ord($value[($length = self::_length($value)) - 1]);
if ($pad and $pad < $block) {
if (preg_match('/'.chr($pad).'{'.$pad.'}$/', $value)) {
return substr($value, 0, $length - $pad);
}
else {
throw new Exception('Decryption error. Padding is invalid.');
}
}
return $value;
}
/**
* Get the encryption key from the application configuration
*
* @param string $key
* @return string
*/
static private function _key($key = NULL) {
if ( ! empty($key)) {
return $key;
}
// Common key
return self::$key;
}
/**
* Base64 encode and make URL safe
*
* @param string $value
* @return string
*/
static private function _b64encodeSafe($value) {
$data = base64_encode($value);
$data = str_replace(array('+', '/', '='), array('-', '_', ''), $data);
return $data;
}
/**
* Base64 decode URL safe string
*
* @param string $value
* @return string
*/
static private function _b64decodeSafe($value) {
$data = str_replace(array('-', '_'), array('+', '/'), $value);
$mod4 = strlen($data) % 4;
if ($mod4) {
$data .= substr('====', $mod4);
}
return base64_decode($data);
}
/**
* Block size
*
* @return int
*/
static private function _block() {
self::$block || self::$block = 24;
return self::$block;
}
/**
* Find hash algorithm
*
* @param string $algo
* @return string
*/
static private function _algo($algo = '') {
// Force to lower case and trim it
$algo = strtolower(trim((string) $algo));
// Algorithm not specified, use the fallback
if ( ! $algo) {
$algo = self::$algo;
}
// Algorithm not recognized. Set to a default
if ( ! in_array($algo, hash_algos())) {
$algo = 'sha256';
}
return $algo;
}
/**
* Get the length of a string
*
* @param string $value
* @param string $encoding
* @return int
*/
static private function _length($value = '', $encoding = 'UTF-8') {
return (function_exists('mb_get_info')) ? mb_strlen($value, $encoding) : strlen($value);
}
}
<?php
var_dump( Crypt::encrypt('Hello, world!') );
var_dump( Crypt::decrypt('Pzgsh33jYNAwzr2mb6id6RW5_Kqeg3Knf7pVpIpQeGhR0UEmvVVk0jzTy-Yx1Wc77Nl2TlZWvvkKDBsjolEL0Q') );
Crypt::key('B617wXZ~&6f5r4rN2jsj5VB*L-5;n#');
var_dump( Crypt::encrypt('Hello, world!') );
var_dump( Crypt::decrypt('2ZqJpkVGRUvgvPgXrSvBey99hBq6JHFA4J9F1QznK9SfOZnpJzSUnYb0EPHywJ6MYUHwVwjm3-fVNKqm3LyyhQ') );
var_dump( Crypt::make('Hello, world!') );
var_dump( Crypt::make('Hello, world!', 'md5') );
var_dump( Crypt::make('Hello, world!', 'FakeHashType') );
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