function _setupInlineCrypt()
{
// Note: _setupInlineCrypt() will be called only if $this->changed === true
// So here we are'nt under the same heavy timing-stress as we are in _de/encryptBlock() or de/encrypt().
// However...the here generated function- $code, stored as php callback in $this->inline_crypt, must work as fast as even possible.
$lambda_functions =& self::_getLambdaFunctions();
// We create max. 10 hi-optimized code for memory reason. Means: For each $key one ultra fast inline-crypt function.
// (Currently, for Crypt_Rijndael/AES, one generated $lambda_function cost on php5.5@32bit ~80kb unfreeable mem and ~130kb on php5.5@64bit)
// After that, we'll still create very fast optimized code but not the hi-ultimative code, for each $mode one.
$gen_hi_opt_code = (bool) (count($lambda_functions) < 10);
// Generation of a uniqe hash for our generated code
$code_hash = "Crypt_Rijndael, {$this->mode}, {$this->Nr}, {$this->Nb}";
if ($gen_hi_opt_code) {
$code_hash = str_pad($code_hash, 32) . $this->_hashInlineCryptFunction($this->key);
}
if (!isset($lambda_functions[$code_hash])) {
switch (true) {
case $gen_hi_opt_code:
// The hi-optimized $lambda_functions will use the key-words hardcoded for better performance.
$w = $this->w;
$dw = $this->dw;
$init_encrypt = '';
$init_decrypt = '';
break;
default:
for ($i = 0, $cw = count($this->w); $i < $cw; ++$i) {
$w[] = '$w[' . $i . ']';
$dw[] = '$dw[' . $i . ']';
}
$init_encrypt = '$w = $self->w;';
$init_decrypt = '$dw = $self->dw;';
}
$Nr = $this->Nr;
$Nb = $this->Nb;
$c = $this->c;
// Generating encrypt code:
$init_encrypt .= '
static $tables;
if (empty($tables)) {
$tables = &$self->_getTables();
}
$t0 = $tables[0];
$t1 = $tables[1];
$t2 = $tables[2];
$t3 = $tables[3];
$sbox = $tables[4];
';
$s = 'e';
$e = 's';
$wc = $Nb - 1;
// Preround: addRoundKey
$encrypt_block = '$in = unpack("N*", $in);' . "\n";
for ($i = 0; $i < $Nb; ++$i) {
$encrypt_block .= '$s' . $i . ' = $in[' . ($i + 1) . '] ^ ' . $w[++$wc] . ";\n";
}
// Mainrounds: shiftRows + subWord + mixColumns + addRoundKey
for ($round = 1; $round < $Nr; ++$round) {
list($s, $e) = array($e, $s);
for ($i = 0; $i < $Nb; ++$i) {
$encrypt_block .= '$' . $e . $i . ' =
$t0[($' . $s . $i . ' >> 24) & 0xff] ^
$t1[($' . $s . ($i + $c[1]) % $Nb . ' >> 16) & 0xff] ^
$t2[($' . $s . ($i + $c[2]) % $Nb . ' >> 8) & 0xff] ^
$t3[ $' . $s . ($i + $c[3]) % $Nb . ' & 0xff] ^
' . $w[++$wc] . ";\n";
}
}
// Finalround: subWord + shiftRows + addRoundKey
for ($i = 0; $i < $Nb; ++$i) {
$encrypt_block .= '$' . $e . $i . ' =
$sbox[ $' . $e . $i . ' & 0xff] |
($sbox[($' . $e . $i . ' >> 8) & 0xff] << 8) |
($sbox[($' . $e . $i . ' >> 16) & 0xff] << 16) |
($sbox[($' . $e . $i . ' >> 24) & 0xff] << 24);' . "\n";
}
$encrypt_block .= '$in = pack("N*"' . "\n";
for ($i = 0; $i < $Nb; ++$i) {
$encrypt_block .= ',
($' . $e . $i . ' & ' . (int) 0xff000000 . ') ^
($' . $e . ($i + $c[1]) % $Nb . ' & 0x00FF0000 ) ^
($' . $e . ($i + $c[2]) % $Nb . ' & 0x0000FF00 ) ^
($' . $e . ($i + $c[3]) % $Nb . ' & 0x000000FF ) ^
' . $w[$i] . "\n";
}
$encrypt_block .= ');';
// Generating decrypt code:
$init_decrypt .= '
static $invtables;
if (empty($invtables)) {
$invtables = &$self->_getInvTables();
}
$dt0 = $invtables[0];
$dt1 = $invtables[1];
$dt2 = $invtables[2];
$dt3 = $invtables[3];
$isbox = $invtables[4];
';
$s = 'e';
$e = 's';
$wc = $Nb - 1;
// Preround: addRoundKey
$decrypt_block = '$in = unpack("N*", $in);' . "\n";
for ($i = 0; $i < $Nb; ++$i) {
$decrypt_block .= '$s' . $i . ' = $in[' . ($i + 1) . '] ^ ' . $dw[++$wc] . ';' . "\n";
}
// Mainrounds: shiftRows + subWord + mixColumns + addRoundKey
for ($round = 1; $round < $Nr; ++$round) {
list($s, $e) = array($e, $s);
for ($i = 0; $i < $Nb; ++$i) {
$decrypt_block .= '$' . $e . $i . ' =
$dt0[($' . $s . $i . ' >> 24) & 0xff] ^
$dt1[($' . $s . ($Nb + $i - $c[1]) % $Nb . ' >> 16) & 0xff] ^
$dt2[($' . $s . ($Nb + $i - $c[2]) % $Nb . ' >> 8) & 0xff] ^
$dt3[ $' . $s . ($Nb + $i - $c[3]) % $Nb . ' & 0xff] ^
' . $dw[++$wc] . ";\n";
}
}
// Finalround: subWord + shiftRows + addRoundKey
for ($i = 0; $i < $Nb; ++$i) {
$decrypt_block .= '$' . $e . $i . ' =
$isbox[ $' . $e . $i . ' & 0xff] |
($isbox[($' . $e . $i . ' >> 8) & 0xff] << 8) |
($isbox[($' . $e . $i . ' >> 16) & 0xff] << 16) |
($isbox[($' . $e . $i . ' >> 24) & 0xff] << 24);' . "\n";
}
$decrypt_block .= '$in = pack("N*"' . "\n";
for ($i = 0; $i < $Nb; ++$i) {
$decrypt_block .= ',
($' . $e . $i . ' & ' . (int) 0xff000000 . ') ^
($' . $e . ($Nb + $i - $c[1]) % $Nb . ' & 0x00FF0000 ) ^
($' . $e . ($Nb + $i - $c[2]) % $Nb . ' & 0x0000FF00 ) ^
($' . $e . ($Nb + $i - $c[3]) % $Nb . ' & 0x000000FF ) ^
' . $dw[$i] . "\n";
}
$decrypt_block .= ');';
$lambda_functions[$code_hash] = $this->_createInlineCryptFunction(array('init_crypt' => '', 'init_encrypt' => $init_encrypt, 'init_decrypt' => $init_decrypt, 'encrypt_block' => $encrypt_block, 'decrypt_block' => $decrypt_block));
}
$this->inline_crypt = $lambda_functions[$code_hash];
}
