PHPRPC Code

/**********************************************************\
|                                                          |
| The implementation of PHPRPC Protocol 3.0                |
|                                                          |
| xxtea.js                                                 |
|                                                          |
| Release 3.0.0 beta 10                                    |
| Copyright (c) 2005-2007 by Team-PHPRPC                   |
|                                                          |
| WebSite:  http://www.phprpc.org/                         |
|           http://www.phprpc.net/                         |
|           http://www.phprpc.com/                         |
|           http://sourceforge.net/projects/php-rpc/       |
|                                                          |
| Authors:  Ma Bingyao <andot@ujn.edu.cn>                  |
|                                                          |
| This file may be distributed and/or modified under the   |
| terms of the GNU Lesser General Public License (LGPL)    |
| version 2.1 as published by the Free Software Foundation |
| and appearing in the included file LICENSE.              |
|                                                          |
\**********************************************************/

/* XXTEA encryption arithmetic library.
 *
 * Copyright (C) 2006 Ma Bingyao <andot@ujn.edu.cn>
 * Version:      1.5
 * LastModified: Dec 9, 2006
 * This library is free.  You can redistribute it and/or modify it.
 */

function long2str(v, w) {
    var vl = v.length;
    var n = (vl - 1) << 2;
    if (w) {
        var m = v[vl - 1];
        if ((m < n - 3) || (m > n)) return null;
        n = m;
    }
    for (var i = 0; i < vl; i++) {
        v[i] = String.fromCharCode(v[i] & 0xff,
                                   v[i] >>> 8 & 0xff,
                                   v[i] >>> 16 & 0xff, 
                                   v[i] >>> 24 & 0xff);
    }
    if (w) {
        return v.join('').substring(0, n);
    }
    else {
        return v.join('');
    }
}

function str2long(s, w) {
    var len = s.length;
    var v = [];
    for (var i = 0; i < len; i += 4) {
        v[i >> 2] = s.charCodeAt(i)
                  | s.charCodeAt(i + 1) << 8
                  | s.charCodeAt(i + 2) << 16
                  | s.charCodeAt(i + 3) << 24;
    }
    if (w) {
        v[v.length] = len;
    }
    return v;
}

function xxtea_encrypt(str, key) {
    if (str == "") {
        return "";
    }
    var v = str2long(str, true);
    var k = str2long(key, false);
    if (k.length < 4) {
        k.length = 4;
    }
    var n = v.length - 1;

    var z = v[n], y = v[0], delta = 0x9E3779B9;
    var mx, e, p, q = Math.floor(6 + 52 / (n + 1)), sum = 0;
    while (0 < q--) {
        sum = sum + delta & 0xffffffff;
        e = sum >>> 2 & 3;
        for (p = 0; p < n; p++) {
            y = v[p + 1];
            mx = (z >>> 5 ^ y << 2) + (y >>> 3 ^ z << 4) ^ (sum ^ y) + (k[p & 3 ^ e] ^ z);
            z = v[p] = v[p] + mx & 0xffffffff;
        }
        y = v[0];
        mx = (z >>> 5 ^ y << 2) + (y >>> 3 ^ z << 4) ^ (sum ^ y) + (k[p & 3 ^ e] ^ z);
        z = v[n] = v[n] + mx & 0xffffffff;
    }

    return long2str(v, false);
}

function xxtea_decrypt(str, key) {
    if (str == "") {
        return "";
    }
    var v = str2long(str, false);
    var k = str2long(key, false);
    if (k.length < 4) {
        k.length = 4;
    }
    var n = v.length - 1;

    var z = v[n - 1], y = v[0], delta = 0x9E3779B9;
    var mx, e, p, q = Math.floor(6 + 52 / (n + 1)), sum = q * delta & 0xffffffff;
    while (sum != 0) {
        e = sum >>> 2 & 3;
        for (p = n; p > 0; p--) {
            z = v[p - 1];
            mx = (z >>> 5 ^ y << 2) + (y >>> 3 ^ z << 4) ^ (sum ^ y) + (k[p & 3 ^ e] ^ z);
            y = v[p] = v[p] - mx & 0xffffffff;
        }
        z = v[n];
        mx = (z >>> 5 ^ y << 2) + (y >>> 3 ^ z << 4) ^ (sum ^ y) + (k[p & 3 ^ e] ^ z);
        y = v[0] = v[0] - mx & 0xffffffff;
        sum = sum - delta & 0xffffffff;
    }

    return long2str(v, true);
}