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159.2. PHP

159.2.1. AES/ECB/PKCS5Padding

<?php class CryptAES { protected $cipher = MCRYPT_RIJNDAEL_128; protected $mode = MCRYPT_MODE_ECB; protected $pad_method = NULL; protected $secret_key = ''; protected $iv = ''; public function set_cipher($cipher) { $this->cipher = $cipher; } public function set_mode($mode) { $this->mode = $mode; } public function set_iv($iv) { $this->iv = $iv; } public function set_key($key) { $this->secret_key = $key; } public function require_pkcs5() { $this->pad_method = 'pkcs5'; } protected function pad_or_unpad($str, $ext) { if ( is_null($this->pad_method) ) { return $str; } else { $func_name = __CLASS__ . '::' . $this->pad_method . '_' . $ext . 'pad'; if ( is_callable($func_name) ) { $size = mcrypt_get_block_size($this->cipher, $this->mode); return call_user_func($func_name, $str, $size); } } return $str; } protected function pad($str) { return $this->pad_or_unpad($str, ''); } protected function unpad($str) { return $this->pad_or_unpad($str, 'un'); } public function encrypt($str) { $str = $this->pad($str); $td = mcrypt_module_open($this->cipher, '', $this->mode, ''); if ( empty($this->iv) ) { $iv = @mcrypt_create_iv(mcrypt_enc_get_iv_size($td), MCRYPT_RAND); } else { $iv = $this->iv; } mcrypt_generic_init($td, $this->secret_key, $iv); $cyper_text = mcrypt_generic($td, $str); //$rt = bin2hex($cyper_text); $rt = base64_encode($cyper_text); mcrypt_generic_deinit($td); mcrypt_module_close($td); return $rt; } public function decrypt($str){ $td = mcrypt_module_open($this->cipher, '', $this->mode, ''); if ( empty($this->iv) ) { $iv = @mcrypt_create_iv(mcrypt_enc_get_iv_size($td), MCRYPT_RAND); } else { $iv = $this->iv; } mcrypt_generic_init($td, $this->secret_key, $iv); //$decrypted_text = mdecrypt_generic($td, self::hex2bin($str)); $decrypted_text = mdecrypt_generic($td, base64_decode($str)); $rt = $decrypted_text; mcrypt_generic_deinit($td); mcrypt_module_close($td); return $this->unpad($rt); } public static function hex2bin($hexdata) { $bindata = ''; $length = strlen($hexdata); for ($i=0; $i < $length; $i += 2) { $bindata .= chr(hexdec(substr($hexdata, $i, 2))); } return $bindata; } public static function pkcs5_pad($text, $blocksize) { $pad = $blocksize - (strlen($text) % $blocksize); return $text . str_repeat(chr($pad), $pad); } public static function pkcs5_unpad($text) { $pad = ord($text{strlen($text) - 1}); if ($pad > strlen($text)) return false; if (strspn($text, chr($pad), strlen($text) - $pad) != $pad) return false; return substr($text, 0, -1 * $pad); } } $aes = new CryptAES(); $aes->set_key('NGjPs5cgNS497sdx'); $aes->require_pkcs5(); $rt = $aes->encrypt('ABC'); echo $rt . '<br/>'; echo $aes->decrypt($rt) . '<br/>';