Get logged on windows username

Question

Hi,
I have a tomcat server running my webapps.
And I need a way to retrieve the username of user(client) currently logged on(windows) .
Any help will be great.
Thanks

Answer 1

this is all that you need copy the code and save it as a .jsp file
<%@ page import="sun.misc.BASE64Encoder,java.util.regex.*" %>
<p><h1>Network Windows USERNAME without any login (ie)</h1></p>
<%
String auth = request.getHeader("Authorization");
if (auth == null) {
        response.setStatus(response.SC_UNAUTHORIZED);
        response.setHeader("WWW-Authenticate", "NTLM");
        return;
if (auth.startsWith("NTLM ")) {
        byte[] msg = new sun.misc.BASE64Decoder().decodeBuffer(auth.substring(5));
        int off = 0, length, offset;
        String s;
        if (msg[8] == 1) {
            off = 18;
            byte z = 0;
            byte[] msg1 = {(byte)'N', (byte)'T', (byte)'L', (byte)'M', (byte)'S',
                            (byte)'S', (byte)'P', z,
                            (byte)2, z, z, z, z, z, z, z,
                            (byte)40, z, z, z, (byte)1, (byte)130, z, z,
                            z, (byte)2, (byte)2, (byte)2, z, z, z, z, //
                            z, z, z, z, z, z, z, z};
            response.setStatus(response.SC_UNAUTHORIZED);
            response.setHeader("WWW-Authenticate", "NTLM "
                  + new sun.misc.BASE64Encoder().encodeBuffer(msg1).trim());
            return;
        else if (msg[8] == 3) {
                off = 30;
                length = msg[off+17]*256 + msg[off+16];
                offset = msg[off+19]*256 + msg[off+18];
                s = new String(msg, offset, length);
                //out.println(s + " ");
        else
                return;
        length = msg[off+1]*256 + msg[off];
        offset = msg[off+3]*256 + msg[off+2];
        s = new String(msg, offset, length);
        //out.println(s + " ");
        length = msg[off+9]*256 + msg[off+8];
        offset = msg[off+11]*256 + msg[off+10];
        s = new String(msg, offset, length);
          Pattern pat = Pattern.compile("[a-z,A-Z,0-9]+");
          Matcher mat = pat.matcher(s);
          String s1 = "";
          while(mat.find())
                         System.out.println("Got name: "+mat.group());
                         s1 = s1+mat.group();
          System.out.println("Got name: "+s1);
          if(s.indexOf('.')!=-1)
               System.out.println("dots!!!");
          s.replaceAll("[.]","");
          System.out.println("Got name again: "+s);
        out.println(s);
        out.println("Hello  <span style='position:relative; width:190;"
            + " height:10;filter:glow(Color=#009966,Strength=1)'>");
        out.println(s + "</SPAN>");
          out.println("<br><br><b>"+s+"</b>");
%></BODY>