关于phpAES
phpAES是128、192和256位AES加密密码的PHP 5（现在包括PHP 4版本）类实现。它*不需要* mcrypt扩展，或任何其他扩展都可以编译成PHP，它使用100％PHP，并且完全符合FIPS 197要求。PHP 5和PHP 4版本都与32位和64位系统兼容。
支持的密码模式包括：电子密码本（ECB），密码块链接（CBC），密码反馈（CFB）和输出反馈（OFB）。
什么是AES？
AES（高级加密标准）是美国政府为所有最高机密文档选择的加密算法。AES利用三种不同的密钥长度为您的应用程序提供不同数量的安全性和速度。
class Aes
{
// The number of 32-bit words comprising the plaintext and columns comrising the state matrix of an AES cipher.
private static $Nb = 4;
// The number of 32-bit words comprising the cipher key in this AES cipher.
private $Nk;
// The number of rounds in this AES cipher.
private $Nr;
// The S-Box substitution table.
private static $sBox = array(
0x63, 0x7c, 0x77, 0x7b, 0xf2, 0x6b, 0x6f, 0xc5,
0x30, 0x01, 0x67, 0x2b, 0xfe, 0xd7, 0xab, 0x76,
0xca, 0x82, 0xc9, 0x7d, 0xfa, 0x59, 0x47, 0xf0,
0xad, 0xd4, 0xa2, 0xaf, 0x9c, 0xa4, 0x72, 0xc0,
0xb7, 0xfd, 0x93, 0x26, 0x36, 0x3f, 0xf7, 0xcc,
0x34, 0xa5, 0xe5, 0xf1, 0x71, 0xd8, 0x31, 0x15,
0x04, 0xc7, 0x23, 0xc3, 0x18, 0x96, 0x05, 0x9a,
0x07, 0x12, 0x80, 0xe2, 0xeb, 0x27, 0xb2, 0x75,
0x09, 0x83, 0x2c, 0x1a, 0x1b, 0x6e, 0x5a, 0xa0,
0x52, 0x3b, 0xd6, 0xb3, 0x29, 0xe3, 0x2f, 0x84,
0x53, 0xd1, 0x00, 0xed, 0x20, 0xfc, 0xb1, 0x5b,
0x6a, 0xcb, 0xbe, 0x39, 0x4a, 0x4c, 0x58, 0xcf,
0xd0, 0xef, 0xaa, 0xfb, 0x43, 0x4d, 0x33, 0x85,
0x45, 0xf9, 0x02, 0x7f, 0x50, 0x3c, 0x9f, 0xa8,
0x51, 0xa3, 0x40, 0x8f, 0x92, 0x9d, 0x38, 0xf5,
0xbc, 0xb6, 0xda, 0x21, 0x10, 0xff, 0xf3, 0xd2,
0xcd, 0x0c, 0x13, 0xec, 0x5f, 0x97, 0x44, 0x17,
0xc4, 0xa7, 0x7e, 0x3d, 0x64, 0x5d, 0x19, 0x73,
0x60, 0x81, 0x4f, 0xdc, 0x22, 0x2a, 0x90, 0x88,
0x46, 0xee, 0xb8, 0x14, 0xde, 0x5e, 0x0b, 0xdb,
0xe0, 0x32, 0x3a, 0x0a, 0x49, 0x06, 0x24, 0x5c,
0xc2, 0xd3, 0xac, 0x62, 0x91, 0x95, 0xe4, 0x79,
0xe7, 0xc8, 0x37, 0x6d, 0x8d, 0xd5, 0x4e, 0xa9,
0x6c, 0x56, 0xf4, 0xea, 0x65, 0x7a, 0xae, 0x08,
0xba, 0x78, 0x25, 0x2e, 0x1c, 0xa6, 0xb4, 0xc6,
0xe8, 0xdd, 0x74, 0x1f, 0x4b, 0xbd, 0x8b, 0x8a,
0x70, 0x3e, 0xb5, 0x66, 0x48, 0x03, 0xf6, 0x0e,
0x61, 0x35, 0x57, 0xb9, 0x86, 0xc1, 0x1d, 0x9e,
0xe1, 0xf8, 0x98, 0x11, 0x69, 0xd9, 0x8e, 0x94,
0x9b, 0x1e, 0x87, 0xe9, 0xce, 0x55, 0x28, 0xdf,
0x8c, 0xa1, 0x89, 0x0d, 0xbf, 0xe6, 0x42, 0x68,
0x41, 0x99, 0x2d, 0x0f, 0xb0, 0x54, 0xbb, 0x16
);
// The inverse S-Box substitution table.
private static $invSBox = array(
0x52, 0x09, 0x6a, 0xd5, 0x30, 0x36, 0xa5, 0x38,
0xbf, 0x40, 0xa3, 0x9e, 0x81, 0xf3, 0xd7, 0xfb,
0x7c, 0xe3, 0x39, 0x82, 0x9b, 0x2f, 0xff, 0x87,
0x34, 0x8e, 0x43, 0x44, 0xc4, 0xde, 0xe9, 0xcb,
0x54, 0x7b, 0x94, 0x32, 0xa6, 0xc2, 0x23, 0x3d,
0xee, 0x4c, 0x95, 0x0b, 0x42, 0xfa, 0xc3, 0x4e,
0x08, 0x2e, 0xa1, 0x66, 0x28, 0xd9, 0x24, 0xb2,
0x76, 0x5b, 0xa2, 0x49, 0x6d, 0x8b, 0xd1, 0x25,
0x72, 0xf8, 0xf6, 0x64, 0x86, 0x68, 0x98, 0x16,
0xd4, 0xa4, 0x5c, 0xcc, 0x5d, 0x65, 0xb6, 0x92,
0x6c, 0x70, 0x48, 0x50, 0xfd, 0xed, 0xb9, 0xda,
0x5e, 0x15, 0x46, 0x57, 0xa7, 0x8d, 0x9d, 0x84,
0x90, 0xd8, 0xab, 0x00, 0x8c, 0xbc, 0xd3, 0x0a,
0xf7, 0xe4, 0x58, 0x05, 0xb8, 0xb3, 0x45, 0x06,
0xd0, 0x2c, 0x1e, 0x8f, 0xca, 0x3f, 0x0f, 0x02,
0xc1, 0xaf, 0xbd, 0x03, 0x01, 0x13, 0x8a, 0x6b,
0x3a, 0x91, 0x11, 0x41, 0x4f, 0x67, 0xdc, 0xea,
0x97, 0xf2, 0xcf, 0xce, 0xf0, 0xb4, 0xe6, 0x73,
0x96, 0xac, 0x74, 0x22, 0xe7, 0xad, 0x35, 0x85,
0xe2, 0xf9, 0x37, 0xe8, 0x1c, 0x75, 0xdf, 0x6e,
0x47, 0xf1, 0x1a, 0x71, 0x1d, 0x29, 0xc5, 0x89,
0x6f, 0xb7, 0x62, 0x0e, 0xaa, 0x18, 0xbe, 0x1b,
0xfc, 0x56, 0x3e, 0x4b, 0xc6, 0xd2, 0x79, 0x20,
0x9a, 0xdb, 0xc0, 0xfe, 0x78, 0xcd, 0x5a, 0xf4,
0x1f, 0xdd, 0xa8, 0x33, 0x88, 0x07, 0xc7, 0x31,
0xb1, 0x12, 0x10, 0x59, 0x27, 0x80, 0xec, 0x5f,
0x60, 0x51, 0x7f, 0xa9, 0x19, 0xb5, 0x4a, 0x0d,
0x2d, 0xe5, 0x7a, 0x9f, 0x93, 0xc9, 0x9c, 0xef,
0xa0, 0xe0, 0x3b, 0x4d, 0xae, 0x2a, 0xf5, 0xb0,
0xc8, 0xeb, 0xbb, 0x3c, 0x83, 0x53, 0x99, 0x61,
0x17, 0x2b, 0x04, 0x7e, 0xba, 0x77, 0xd6, 0x26,
0xe1, 0x69, 0x14, 0x63, 0x55, 0x21, 0x0c, 0x7d
);
// Log table based on 0xe5
private static $ltable = array(
0x00, 0xff, 0xc8, 0x08, 0x91, 0x10, 0xd0, 0x36,
0x5a, 0x3e, 0xd8, 0x43, 0x99, 0x77, 0xfe, 0x18,
0x23, 0x20, 0x07, 0x70, 0xa1, 0x6c, 0x0c, 0x7f,
0x62, 0x8b, 0x40, 0x46, 0xc7, 0x4b, 0xe0, 0x0e,
0xeb, 0x16, 0xe8, 0xad, 0xcf, 0xcd, 0x39, 0x53,
0x6a, 0x27, 0x35, 0x93, 0xd4, 0x4e, 0x48, 0xc3,
0x2b, 0x79, 0x54, 0x28, 0x09, 0x78, 0x0f, 0x21,
0x90, 0x87, 0x14, 0x2a, 0xa9, 0x9c, 0xd6, 0x74,
0xb4, 0x7c, 0xde, 0xed, 0xb1, 0x86, 0x76, 0xa4,
0x98, 0xe2, 0x96, 0x8f, 0x02, 0x32, 0x1c, 0xc1,
0x33, 0xee, 0xef, 0x81, 0xfd, 0x30, 0x5c, 0x13,
0x9d, 0x29, 0x17, 0xc4, 0x11, 0x44, 0x8c, 0x80,
0xf3, 0x73, 0x42, 0x1e, 0x1d, 0xb5, 0xf0, 0x12,
0xd1, 0x5b, 0x41, 0xa2, 0xd7, 0x2c, 0xe9, 0xd5,
0x59, 0xcb, 0x50, 0xa8, 0xdc, 0xfc, 0xf2, 0x56,
0x72, 0xa6, 0x65, 0x2f, 0x9f, 0x9b, 0x3d, 0xba,
0x7d, 0xc2, 0x45, 0x82, 0xa7, 0x57, 0xb6, 0xa3,
0x7a, 0x75, 0x4f, 0xae, 0x3f, 0x37, 0x6d, 0x47,
0x61, 0xbe, 0xab, 0xd3, 0x5f, 0xb0, 0x58, 0xaf,
0xca, 0x5e, 0xfa, 0x85, 0xe4, 0x4d, 0x8a, 0x05,
0xfb, 0x60, 0xb7, 0x7b, 0xb8, 0x26, 0x4a, 0x67,
0xc6, 0x1a, 0xf8, 0x69, 0x25, 0xb3, 0xdb, 0xbd,
0x66, 0xdd, 0xf1, 0xd2, 0xdf, 0x03, 0x8d, 0x34,
0xd9, 0x92, 0x0d, 0x63, 0x55, 0xaa, 0x49, 0xec,
0xbc, 0x95, 0x3c, 0x84, 0x0b, 0xf5, 0xe6, 0xe7,
0xe5, 0xac, 0x7e, 0x6e, 0xb9, 0xf9, 0xda, 0x8e,
0x9a, 0xc9, 0x24, 0xe1, 0x0a, 0x15, 0x6b, 0x3a,
0xa0, 0x51, 0xf4, 0xea, 0xb2, 0x97, 0x9e, 0x5d,
0x22, 0x88, 0x94, 0xce, 0x19, 0x01, 0x71, 0x4c,
0xa5, 0xe3, 0xc5, 0x31, 0xbb, 0xcc, 0x1f, 0x2d,
0x3b, 0x52, 0x6f, 0xf6, 0x2e, 0x89, 0xf7, 0xc0,
0x68, 0x1b, 0x64, 0x04, 0x06, 0xbf, 0x83, 0x38
);
// Inverse log table
private static $atable = array(
0x01, 0xe5, 0x4c, 0xb5, 0xfb, 0x9f, 0xfc, 0x12,
0x03, 0x34, 0xd4, 0xc4, 0x16, 0xba, 0x1f, 0x36,
0x05, 0x5c, 0x67, 0x57, 0x3a, 0xd5, 0x21, 0x5a,
0x0f, 0xe4, 0xa9, 0xf9, 0x4e, 0x64, 0x63, 0xee,
0x11, 0x37, 0xe0, 0x10, 0xd2, 0xac, 0xa5, 0x29,
0x33, 0x59, 0x3b, 0x30, 0x6d, 0xef, 0xf4, 0x7b,
0x55, 0xeb, 0x4d, 0x50, 0xb7, 0x2a, 0x07, 0x8d,
0xff, 0x26, 0xd7, 0xf0, 0xc2, 0x7e, 0x09, 0x8c,
0x1a, 0x6a, 0x62, 0x0b, 0x5d, 0x82, 0x1b, 0x8f,
0x2e, 0xbe, 0xa6, 0x1d, 0xe7, 0x9d, 0x2d, 0x8a,
0x72, 0xd9, 0xf1, 0x27, 0x32, 0xbc, 0x77, 0x85,
0x96, 0x70, 0x08, 0x69, 0x56, 0xdf, 0x99, 0x94,
0xa1, 0x90, 0x18, 0xbb, 0xfa, 0x7a, 0xb0, 0xa7,
0xf8, 0xab, 0x28, 0xd6, 0x15, 0x8e, 0xcb, 0xf2,
0x13, 0xe6, 0x78, 0x61, 0x3f, 0x89, 0x46, 0x0d,
0x35, 0x31, 0x88, 0xa3, 0x41, 0x80, 0xca, 0x17,
0x5f, 0x53, 0x83, 0xfe, 0xc3, 0x9b, 0x45, 0x39,
0xe1, 0xf5, 0x9e, 0x19, 0x5e, 0xb6, 0xcf, 0x4b,
0x38, 0x04, 0xb9, 0x2b, 0xe2, 0xc1, 0x4a, 0xdd,
0x48, 0x0c, 0xd0, 0x7d, 0x3d, 0x58, 0xde, 0x7c,
0xd8, 0x14, 0x6b, 0x87, 0x47, 0xe8, 0x79, 0x84,
0x73, 0x3c, 0xbd, 0x92, 0xc9, 0x23, 0x8b, 0x97,
0x95, 0x44, 0xdc, 0xad, 0x40, 0x65, 0x86, 0xa2,
0xa4, 0xcc, 0x7f, 0xec, 0xc0, 0xaf, 0x91, 0xfd,
0xf7, 0x4f, 0x81, 0x2f, 0x5b, 0xea, 0xa8, 0x1c,
0x02, 0xd1, 0x98, 0x71, 0xed, 0x25, 0xe3, 0x24,
0x06, 0x68, 0xb3, 0x93, 0x2c, 0x6f, 0x3e, 0x6c,
0x0a, 0xb8, 0xce, 0xae, 0x74, 0xb1, 0x42, 0xb4,
0x1e, 0xd3, 0x49, 0xe9, 0x9c, 0xc8, 0xc6, 0xc7,
0x22, 0x6e, 0xdb, 0x20, 0xbf, 0x43, 0x51, 0x52,
0x66, 0xb2, 0x76, 0x60, 0xda, 0xc5, 0xf3, 0xf6,
0xaa, 0xcd, 0x9a, 0xa0, 0x75, 0x54, 0x0e, 0x01
);
// The key schedule in this AES cipher.
private $w = array(); // Nb*(Nr+1) 32-bit words
// The state matrix in this AES cipher with Nb columns and 4 rows
private $s = array(array());
// The block cipher mode of operation
private $mode;
// The initialization vector used in advanced cipher modes
private $iv;
/**
* Constructs an AES cipher using a specific key.
*
* @throws LengthException if the initialization vector or key is not the
* appropriate length.
*/
public function __construct($z, $mode = 'ECB', $iv = null)
{
$this->mode = strtoupper($mode);
$this->iv = $iv;
$this->Nk = strlen($z)/4;
$this->Nr = $this->Nk + self::$Nb + 2;
if ($this->mode != 'ECB' && strlen($this->iv) != 16) {
throw new \LengthException(
'The initialization vector must be 128 bits (or 16 characters) long.'
);
}
if ($this->Nk != 4 && $this->Nk != 6 && $this->Nk != 8) {
throw new \LengthException(
'Key is ' . ($this->Nk*32) . ' bits long. *not* 128, 192, or 256.'
);
}
$this->Nr = $this->Nk+self::$Nb+2;
$this->keyExpansion($z); // places expanded key in w
}
public function __destruct()
{
unset($this->w);
unset($this->s);
}
/**
* Encrypts an aribtrary length String.
* @params plaintext string
* @returns ciphertext string
*/
public function encrypt($x)
{
$t = ''; // 16-byte block to hold the temporary input of the cipher
$y = ''; // returned cipher text;
$y_block = $this->iv; // 16-byte block to hold the temporary output of the cipher
$xsize = strlen($x);
switch ($this->mode) {
case 'ECB':
// put a 16-byte block into t, ecnrypt it and add it to the result
for ($i = 0; $i < $xsize; $i += 16) {
for ($j = 0; $j < 16; $j++) {
if (($i+$j)<$xsize) {
$t[$j] = $x[$i+$j];
} else {
$t[$j] = chr(0);
}
}
$y_block = $this->encryptBlock($t);
$y .= $y_block;
}
break;
case 'CBC':
// put a 16-byte block into t, ecnrypt it and add it to the result
for ($i = 0; $i < $xsize; $i += 16) {
for ($j=0; $j<16; $j++) {
// XOR this block of plaintext with the initialization vector
$t[$j] = chr(ord(($i+$j)<$xsize ? $x[$i+$j] : chr(0)) ^ ord($y_block[$j]));
}
$y_block = $this->encryptBlock($t);
$y .= $y_block;
}
break;
case 'CFB':
for ($i = 0; $i < $xsize; $i += 16) {
// Encrypt the initialization vector/cipher output then XOR with the plaintext
$y_block = $this->encryptBlock($y_block);
for ($j = 0; $j < 16; $j++) {
// XOR the cipher output with the plaintext.
$y_block[$j] = chr(ord(($i+$j)<$xsize ? $x[$i+$j] : chr(0)) ^ ord($y_block[$j]));
}
$y .= $y_block;
}
break;
case 'OFB':
for ($i = 0; $i < $xsize; $i += 16) {
// Encrypt the initialization vector/cipher output then XOR with the plaintext
$t = $this->encryptBlock($y_block);
for ($j = 0; $j < 16; $j++) {
// XOR the cipher output with the plaintext.
$y_block[$j] = chr(ord(($i+$j)<$xsize ? $x[$i+$j] : chr(0)) ^ ord($t[$j]));
}
$y .= $y_block;
$y_block = $t;
}
break;
}
return $y;
}
/**
* Decrypts an aribtrary length String.
* @params ciphertext string
* @returns plaintext string
*/
public function decrypt($y)
{
$t = array(); // 16-byte block
$x = ''; // returned plain text;
$y_block = $this->iv;
$x_block = '';
// put a 16-byte block into t
$ysize = strlen($y);
switch ($this->mode) {
case 'ECB':
for ($i = 0; $i < $ysize; $i += 16) {
for ($j = 0; $j < 16; $j++) {
if (($i+$j) < $ysize) {
$t[$j] = $y[$i+$j];
} else {
$t[$j] = chr(0);
}
}
$x_block = $this->decryptBlock($t);
$x .= $x_block;
}
break;
case 'CBC':
for ($i = 0; $i < $ysize; $i += 16) {
for ($j = 0; $j < 16; $j++) {
if (($i+$j)<$ysize) {
$t[$j] = $y[$i+$j];
} else {
$t[$j] = chr(0);
}
}
$x_block = $this->decryptBlock($t);
// XOR the iv/previous cipher block with this decrypted cipher block
for ($j = 0; $j < 16; $j++) {
$x_block[$j] = chr(ord($x_block[$j]) ^ ord($y_block[$j]));
}
$y_block = $t;
$x .= $x_block;
}
break;
case 'CFB':
for ($i = 0; $i < $ysize; $i += 16) {
// Encrypt the initialization vector/cipher output then XOR with the ciphertext
$x_block = $this->encryptBlock($y_block);
for ($j = 0; $j < 16; $j++) {
// XOR the cipher output with the ciphertext.
$x_block[$j] = chr(ord(($i+$j)<$ysize ? $y[$i+$j] : chr(0)) ^ ord($x_block[$j]));
$y_block[$j] = $y[$i+$j];
}
$x .= $x_block;
}
break;
case 'OFB':
$x = $this->encrypt($y);
break;
}
return rtrim($x, chr(0)); // Remove any buffer residue on return.
}
/**
* Encrypts the 16-byte plain text.
* @params 16-byte plaintext string
* @returns 16-byte ciphertext string
*/
public function encryptBlock($x)
{
$y = ''; // 16-byte string
// place input x into the initial state matrix in column order
for ($i = 0; $i <4*self::$Nb; $i++) {
// we want integerger division for the second index
$this->s[$i%4][($i-$i%self::$Nb)/self::$Nb] = ord($x[$i]);
}
// add round key
$this->addRoundKey(0);
for ($i = 1; $i < $this->Nr; $i++) {
// substitute bytes
$this->subBytes();
// shift rows
$this->shiftRows();
// mix columns
$this->mixColumns();
// add round key
$this->addRoundKey($i);
}
// substitute bytes
$this->subBytes();
// shift rows
$this->shiftRows();
// add round key
$this->addRoundKey($i);
// place state matrix s into y in column order
for ($i = 0; $i < 4*self::$Nb; $i++) {
$y .= chr($this->s[$i%4][($i-$i%self::$Nb)/self::$Nb]);
}
return $y;
}
/**
* Decrypts the 16-byte cipher text.
* @params 16-byte ciphertext string
* @returns 16-byte plaintext string
*/
public function decryptBlock($y)
{
$x = ''; // 16-byte string
// place input y into the initial state matrix in column order
for ($i = 0; $i < 4*self::$Nb; $i++) {
$this->s[$i%4][($i-$i%self::$Nb)/self::$Nb] = ord($y[$i]);
}
// add round key
$this->addRoundKey($this->Nr);
for ($i = $this->Nr-1; $i > 0; $i--) {
// inverse shift rows
$this->invShiftRows();
// inverse sub bytes
$this->invSubBytes();
// add round key
$this->addRoundKey($i);
// inverse mix columns
$this->invMixColumns();
}
// inverse shift rows
$this->invShiftRows();
// inverse sub bytes
$this->invSubBytes();
// add round key
$this->addRoundKey($i);
// place state matrix s into x in column order
for ($i = 0; $i < 4*self::$Nb; $i++) {
// Used to remove filled null characters.
$x .= chr($this->s[$i%4][($i-$i%self::$Nb)/self::$Nb]);
}
return $x;
}
/**
* Makes a big key out of a small one
* @returns void
*/
private function keyExpansion($z)
{
// Rcon is the round constant
static $Rcon = array(
0x00000000,
0x01000000,
0x02000000,
0x04000000,
0x08000000,
0x10000000,
0x20000000,
0x40000000,
0x80000000,
0x1b000000,
0x36000000,
0x6c000000,
0xd8000000,
0xab000000,
0x4d000000,
0x9a000000,
0x2f000000
);
$temp = 0; // temporary 32-bit word
// the first Nk words of w are the cipher key z
for ($i = 0; $i < $this->Nk; $i++) {
$this->w[$i] = 0;
// fill an entire word of expanded key w
// by pushing 4 bytes into the w[i] word
$this->w[$i] = ord($z[4*$i]); // add a byte in
$this->w[$i] <<= 8; // make room for the next byte
$this->w[$i] += ord($z[4*$i+1]);
$this->w[$i] <<= 8;
$this->w[$i] += ord($z[4*$i+2]);
$this->w[$i] <<= 8;
$this->w[$i] += ord($z[4*$i+3]);
}
for (; $i < self::$Nb*($this->Nr+1); $i++) {
$temp = $this->w[$i-1];
if ($i%$this->Nk == 0) {
$temp = $this->subWord($this->rotWord($temp)) ^ $Rcon[$i/$this->Nk];
} elseif ($this->Nk > 6 && $i%$this->Nk == 4) {
$temp = $this->subWord($temp);
}
$this->w[$i] = $this->w[$i-$this->Nk] ^ $temp;
self::make32BitWord($this->w[$i]);
}
}
/**
* Adds the key schedule for a round to a state matrix.
* @returns void
*/
private function addRoundKey($round)
{
$temp = '';
for ($i = 0; $i < 4; $i++) {
for ($j = 0; $j < self::$Nb; $j++) {
// place the i-th byte of the j-th word from expanded key w into temp
$temp = $this->w[$round*self::$Nb+$j] >> (3-$i)*8;
// Cast temp from a 32-bit word into an 8-bit byte.
$temp %= 256;
// Can't do unsigned shifts, so we need to make this temp positive
$temp = ($temp < 0 ? (256 + $temp) : $temp);
$this->s[$i][$j] ^= $temp; // xor temp with the byte at location (i,j) of the state
}
}
}
/**
* Unmixes each column of a state matrix.
* @returns void
*/
private function invMixColumns()
{
$s0 = $s1 = $s2 = $s3= '';
// There are Nb columns
for ($i = 0; $i < self::$Nb; $i++) {
$s0 = $this->s[0][$i];
$s1 = $this->s[1][$i];
$s2 = $this->s[2][$i];
$s3 = $this->s[3][$i];
$this->s[0][$i] = $this->mult(0x0e, $s0)
^ $this->mult(0x0b, $s1)
^ $this->mult(0x0d, $s2)
^ $this->mult(0x09, $s3);
$this->s[1][$i] = $this->mult(0x09, $s0)
^ $this->mult(0x0e, $s1)
^ $this->mult(0x0b, $s2)
^ $this->mult(0x0d, $s3);
$this->s[2][$i] = $this->mult(0x0d, $s0)
^ $this->mult(0x09, $s1)
^ $this->mult(0x0e, $s2)
^ $this->mult(0x0b, $s3);
$this->s[3][$i] = $this->mult(0x0b, $s0)
^ $this->mult(0x0d, $s1)
^ $this->mult(0x09, $s2)
^ $this->mult(0x0e, $s3);
}
}
/**
* Applies an inverse cyclic shift to the last 3 rows of a state matrix.
* @returns void
*/
private function invShiftRows()
{
$temp = array();
for ($i = 1; $i < 4; $i++) {
for ($j = 0; $j < self::$Nb; $j++) {
$temp[($i+$j)%self::$Nb] = $this->s[$i][$j];
}
for ($j = 0; $j < self::$Nb; $j++) {
$this->s[$i][$j] = $temp[$j];
}
}
}
/**
* Applies inverse S-Box substitution to each byte of a state matrix.
* @returns void
*/
private function invSubBytes()
{
for ($i = 0; $i < 4; $i++) {
for ($j = 0; $j < self::$Nb; $j++) {
$this->s[$i][$j] = self::$invSBox[$this->s[$i][$j]];
}
}
}
/**
* Mixes each column of a state matrix.
* @returns void
*/
private function mixColumns()
{
$s0 = $s1 = $s2 = $s3= '';
// There are Nb columns
for ($i = 0; $i < self::$Nb; $i++) {
$s0 = $this->s[0][$i];
$s1 = $this->s[1][$i];
$s2 = $this->s[2][$i];
$s3 = $this->s[3][$i];
$this->s[0][$i] = $this->mult(0x02, $s0)
^ $this->mult(0x03, $s1)
^ $this->mult(0x01, $s2)
^ $this->mult(0x01, $s3);
$this->s[1][$i] = $this->mult(0x01, $s0)
^ $this->mult(0x02, $s1)
^ $this->mult(0x03, $s2)
^ $this->mult(0x01, $s3);
$this->s[2][$i] = $this->mult(0x01, $s0)
^ $this->mult(0x01, $s1)
^ $this->mult(0x02, $s2)
^ $this->mult(0x03, $s3);
$this->s[3][$i] = $this->mult(0x03, $s0)
^ $this->mult(0x01, $s1)
^ $this->mult(0x01, $s2)
^ $this->mult(0x02, $s3);
}
}
/**
* Applies a cyclic shift to the last 3 rows of a state matrix.
* @returns void
*/
private function shiftRows()
{
$temp = array();
for ($i = 1; $i < 4; $i++) {
for ($j = 0; $j < self::$Nb; $j++) {
$temp[$j] = $this->s[$i][($j+$i)%self::$Nb];
}
for ($j = 0; $j < self::$Nb; $j++) {
$this->s[$i][$j] = $temp[$j];
}
}
}
/**
* Applies S-Box substitution to each byte of a state matrix.
* @returns void
*/
private function subBytes()
{
for ($i = 0; $i < 4; $i++) {
for ($j = 0; $j < self::$Nb; $j++) {
$this->s[$i][$j] = self::$sBox[$this->s[$i][$j]];
}
}
}
/**
* Multiplies two polynomials a(x), b(x) in GF(2^8) modulo the irreducible polynomial m(x) = x^8+x^4+x^3+x+1
* @returns 8-bit value
*/
private static function mult($a, $b)
{
$sum = self::$ltable[$a] + self::$ltable[$b];
$sum %= 255;
// Get the antilog
$sum = self::$atable[$sum];
return ($a == 0 ? 0 : ($b == 0 ? 0 : $sum));
}
/**
* Applies a cyclic permutation to a 4-byte word.
* @returns 32-bit int
*/
private static function rotWord($w)
{
$temp = $w >> 24; // put the first 8-bits into temp
$w <<= 8; // make room for temp to fill the lower end of the word
self::make32BitWord($w);
// Can't do unsigned shifts, so we need to make this temp positive
$temp += $temp < 0 ? 256 : 0;
$w += $temp;
return $w;
}
/**
* Applies S-box substitution to each byte of a 4-byte word.
* @returns 32-bit int
*/
private static function subWord($w)
{
$temp = 0;
// loop through 4 bytes of a word
for ($i = 0; $i < 4; $i++) {
$temp = $w >> 24; // put the first 8-bits into temp
// Can't do unsigned shifts, so we need to make this temp positive
$temp += $temp < 0 ? 256 : 0;
$w <<= 8; // make room for the substituted byte in w;
self::make32BitWord($w);
$w += self::$sBox[$temp]; // add the substituted byte back
}
self::make32BitWord($w);
return $w;
}
/**
* Reduces a 64-bit word to a 32-bit word
* @returns void
*/
private static function make32BitWord(&$w)
{
// Reduce this 64-bit word to 32-bits on 64-bit machines
$w &= 0x00000000FFFFFFFF;
}
}
?>