com.gwtcx.smartgwt.client.util.SecurityUtil.java Source code

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Here is the source code for com.gwtcx.smartgwt.client.util.SecurityUtil.java

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/**
 * (C) Copyright 2010, 2011 upTick Pty Ltd
 *
 * Licensed under the terms of the GNU General Public License version 3
 * as published by the Free Software Foundation. You may obtain a copy of the
 * License at: http://www.gnu.org/copyleft/gpl.html
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations
 * under the License.
 */

package com.gwtcx.smartgwt.client.util;

import com.google.gwt.user.client.Random;

/**
 * Security functions.
 */
public class SecurityUtil {

    public static String byteStringToHexString(final String s) {
        String r = "";
        for (int i = 0; i < s.length(); i++) {
            r += byteToHexChars(s.charAt(i));
        }
        return r;
    }

    public static String byteToHexChars(final int i) {
        final String s = "0" + Integer.toHexString(i);
        return s.substring(s.length() - 2);
    }

    public static String hexStringToByteString(final String s) {
        String r = "";
        for (int i = 0; i < s.length(); i += 2) {
            r += (char) Integer.parseInt(s.substring(i, i + 2), 16);
        }
        return r;
    }

    public static native String md5(String pText)
    /*-{
      return $wnd.hex_md5(pText);
    }-*/;

    public static native String sha256(String pText)
    /*-{
      return $wnd.hex_sha256(pText);
    }-*/;

    public static native String sha512(String pText)
    /*-{
      return $wnd.hex_sha512(pText);
    }-*/;

    public static String randomCharString() {
        String r = "";
        for (int i = 0; i < 32; i++) {
            r += (char) ('A' + Random.nextInt(26));
        }
        return r;
    }

    private final byte sbox[] = new byte[256];
    private int i;
    private int j;

    public String codeDecode(final String plaintext) {
        byte x;
        String r = "";
        final int pl = plaintext.length();
        for (int k = 0; k < pl; k++) {
            i = i + 1 & 0xff;
            j = j + sbox[i] & 0xff;

            x = sbox[i];
            sbox[i] = sbox[j];
            sbox[j] = x;

            r += (char) (plaintext.charAt(k) ^ sbox[sbox[i] + sbox[j] & 0xff] & 0xff);
        }
        return r;
    }

    public String codeDecode(final String key, final String plaintext) {

        setUp(key);
        return codeDecode(plaintext);
    }

    public void setUp(final String key) {
        int k;
        byte x;

        for (i = 0; i < 256; i++) {
            sbox[i] = (byte) i;
        }

        final int kl = key.length();
        for (i = 0, j = 0, k = 0; i < 256; i++) {
            j = j + sbox[i] + key.charAt(k) & 0xff;
            k = (k + 1) % kl;

            x = sbox[i];
            sbox[i] = sbox[j];
            sbox[j] = x;
        }

        // Set things up to start coding/decoding

        i = 0;
        j = 0;
    }
}