【转】JS前台加密,java后台解密实现

因项目需求，需要一些敏感信息进行加密,不能以明文暴露到浏览器。

然后后台进行解密操作 先看一下效果图

 

未对其加密传输

1.前台JS

<script type="text/javascript">
    $(function() {
        $("#btn").click(function() {
            var username = encode64($("#username").val());  //对数据加密
            var password = encode64($("#password").val());
            $("#username").val(username);
            $("#password").val(password);
            document.fm.submit();  //fm为form表单name
        })
    })

    // base64加密开始
    var keyStr = "ABCDEFGHIJKLMNOP" + "QRSTUVWXYZabcdef" + "ghijklmnopqrstuv"
            + "wxyz0123456789+/" + "=";

    function encode64(input) {

        var output = "";
        var chr1, chr2, chr3 = "";
        var enc1, enc2, enc3, enc4 = "";
        var i = 0;
        do {
            chr1 = input.charCodeAt(i++);
            chr2 = input.charCodeAt(i++);
            chr3 = input.charCodeAt(i++);
            enc1 = chr1 >> 2;
            enc2 = ((chr1 & 3) << 4) | (chr2 >> 4);
            enc3 = ((chr2 & 15) << 2) | (chr3 >> 6);
            enc4 = chr3 & 63;
            if (isNaN(chr2)) {
                enc3 = enc4 = 64;
            } else if (isNaN(chr3)) {
                enc4 = 64;
            }
            output = output + keyStr.charAt(enc1) + keyStr.charAt(enc2)
                    + keyStr.charAt(enc3) + keyStr.charAt(enc4);
            chr1 = chr2 = chr3 = "";
            enc1 = enc2 = enc3 = enc4 = "";
        } while (i < input.length);

        return output;
    }
    // base64加密结束
</script>

2、后台java代码

private static char[] base64EncodeChars = new char[] { 'A', 'B', 'C', 'D',
        'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q',
        'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd',
        'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q',
        'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', '0', '1', '2', '3',
        '4', '5', '6', '7', '8', '9', '+', '/', };

private static byte[] base64DecodeChars = new byte[] { -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
        -1, -1, -1, -1, 62, -1, -1, -1, 63, 52, 53, 54, 55, 56, 57, 58, 59,
        60, 61, -1, -1, -1, -1, -1, -1, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,
        10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1,
        -1, -1, -1, -1, -1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37,
        38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1, -1,
        -1, -1 };

/**
 * 解密
 * @param str
 * @return
 */
public static byte[] decode(String str) {
    byte[] data = str.getBytes();
    int len = data.length;
    ByteArrayOutputStream buf = new ByteArrayOutputStream(len);
    int i = 0;
    int b1, b2, b3, b4;

    while (i < len) {
        do {
            b1 = base64DecodeChars[data[i++]];
        } while (i < len && b1 == -1);
        if (b1 == -1) {
            break;
        }

        do {
            b2 = base64DecodeChars[data[i++]];
        } while (i < len && b2 == -1);
        if (b2 == -1) {
            break;
        }
        buf.write((int) ((b1 << 2) | ((b2 & 0x30) >>> 4)));

        do {
            b3 = data[i++];
            if (b3 == 61) {
                return buf.toByteArray();
            }
            b3 = base64DecodeChars[b3];
        } while (i < len && b3 == -1);
        if (b3 == -1) {
            break;
        }
        buf.write((int) (((b2 & 0x0f) << 4) | ((b3 & 0x3c) >>> 2)));

        do {
            b4 = data[i++];
            if (b4 == 61) {
                return buf.toByteArray();
            }
            b4 = base64DecodeChars[b4];
        } while (i < len && b4 == -1);
        if (b4 == -1) {
            break;
        }
        buf.write((int) (((b3 & 0x03) << 6) | b4));
    }
    return buf.toByteArray();
}

System.out.println(new String(decode(username)));  // 使用decode()方法进行解密

 

Java加密算法还包括如下：

MD5(Message Digest algorithm 5，信息摘要算法)

SHA(Secure Hash Algorithm，安全散列算法)

HMAC(Hash Message Authentication Code，散列消息鉴别码)

待有时间研究这些复杂的高级加密算法

 

作者：itmyhome

源码：download