JAVASCRIPT 客户端加密 PHP服务端解密

<?php session_start();
/** PBKDF2 Implementation (as described in RFC 2898);
 *
 *  @param string p password
 *  @param string s salt
 *  @param int c iteration count (use 1000 or higher)
 *  @param int kl derived key length
 *  @param string a hash algorithm
 *
 *  @return string derived key
 */
function pbkdf2_helper_for_javascript( $p, $s, $c, $kl, $a = 'sha256' ) {
    $hl = strlen( hash( $a, null, true ) );
    $kb = ceil( $kl / $hl );
    $dk = '';
    for ( $block = 1; $block <= $kb; $block++ ) {
        $ib = $b = hash_hmac( $a, $s . pack( 'N', $block ), $p, true );
        for ( $i = 1; $i < $c; $i++ ) {
            $ib ^= ( $b = hash_hmac( $a, $b, $p, true ) );
        }
        $dk .= $ib;
    }
    return substr( $dk, 0, $kl );
}

function dectypt_from_javascript_encrypt($dectypted_str, $callback = null) {
	$salt = $_SESSION['password_salt'];
	$secret_key = $_SESSION['password_secret'];
    //get the cipher key
    $key = pbkdf2_helper_for_javascript( $secret_key, $salt, 1000, 32 );

    //get the IV
    $iv64 = $_REQUEST['iv'];
    $iv = base64_decode($iv64);

    //get the HMAC
    $hmac = $_REQUEST['hmac'];
    
    # initialise mcrypt. NB Rijndael-128 covers all variants of AES
    $td = mcrypt_module_open( MCRYPT_RIJNDAEL_128, '', MCRYPT_MODE_NOFB, '' );
    
    # do encryption
    $input = base64_decode($dectypted_str);
    mcrypt_generic_init($td, $key, $iv);
    $plain = mdecrypt_generic($td, $input);
    mcrypt_generic_deinit($td);
    
    # shutdown mcrypt
    mcrypt_module_close($td);

    # create HMAC for message
    $hmacActual = hash_hmac('sha256', $plain, $iv);
    if($hmac == $hmacActual) {
    	if ($callback && is_callable($callback)) {
    		$callback('success', $plain);
    	}
    } else {
    	//解密失败，提示提醒用户
    	$callback('error', null);
    }

    //session 用完后清除
    $_SESSION['password_secret'] = null;
}

if ($user = @$_POST['user'] && $password = @$_POST['password']) {
  	dectypt_from_javascript_encrypt($_POST['password'], function ($status, $password) {
  		print $password;
  	});
}

// 每次发生请求，生成一次key用来解密.
$key = uniqid();
//发送到客户端cookie
setcookie("password_secret", $key, 0);
setcookie("password_salt", "tuding_salt");
//并且保存到session用来后续的解密
$_SESSION['password_secret'] = $key;
$_SESSION['password_salt'] = 'tuding_salt';

?>




	
		<meta charset="utf-8">
		<script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.8.2/jquery.min.js"></script>
        <script type="text/javascript" src="http://crypto-js.googlecode.com/files/2.5.3-crypto.js"></script>
        <script type="text/javascript" src="http://crypto-js.googlecode.com/files/2.5.3-sha256.js"></script>
        <script type="text/javascript" src="http://crypto-js.googlecode.com/files/2.3.0-hmac.js"></script>
        <script type="text/javascript" src="http://crypto-js.googlecode.com/files/2.3.0-pbkdf2.js"></script>
        <script type="text/javascript" src="http://crypto-js.googlecode.com/files/2.3.0-aes.js"></script>
        <script type="text/javascript" src="http://crypto-js.googlecode.com/files/2.5.3-blockmodes.js"></script>
		<script type="text/javascript">
			function doEncrypt(message) {
				var secret = $.cookie('password_secret');
				var salt = $.cookie('password_salt');
			    var bytes_iv = Crypto.util.randomBytes(16);
			    var base64_iv = Crypto.util.bytesToBase64(bytes_iv);
			    var hmac = Crypto.HMAC(Crypto.SHA256, message, bytes_iv);
			    var key = Crypto.PBKDF2(secret, salt, 32, {hasher:Crypto.SHA256, iterations:1000, asBytes:true});
			    var cipher =Crypto.AES.encrypt(message, key, {iv:bytes_iv, mode:new Crypto.mode.OFB, asBytes:false});
			    return {iv: base64_iv, hmac: hmac, cipher: cipher};
			}
			$(document).ready(function () {
				$('#submit').click(function () {
					var user = $('input[name="user"]').val();
					var pwd = $('input[name="password"]').val();
					try {
						var encrypt_pwd = doEncrypt(pwd);
						$('input[name="hmac"]').val(encrypt_pwd['hmac']);
						$('input[name="password"]').val(encrypt_pwd['cipher']);
						$('input[name="iv"]').val(encrypt_pwd['iv']);
					}
					catch (exception) {
						//TODO:
					}
				});

			});
		</script>