it.attocchi.web.auth.AuthenticationFilter.java Source code

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Here is the source code for it.attocchi.web.auth.AuthenticationFilter.java

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/*
Copyright (c) 2012,2013 Mirco Attocchi
       
This file is part of WebAppCommon.
    
WebAppCommon is free software: you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
    
WebAppCommon is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU Lesser General Public License for more details.
    
You should have received a copy of the GNU Lesser General Public License
along with WebAppCommon.  If not, see <http://www.gnu.org/licenses/>.
*/

package it.attocchi.web.auth;

import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import org.apache.log4j.Logger;

/**
 * 
 * @author Mirco
 */
public class AuthenticationFilter implements Filter {

    private static Logger logger = Logger.getLogger(AuthenticationFilter.class.getName());
    //
    FilterConfig config = null;
    ServletContext servletContext = null;

    public AuthenticationFilter() {
    }

    public void init(FilterConfig filterConfig) throws ServletException {
        config = filterConfig;
        servletContext = config.getServletContext();
    }

    // public void doFilter(ServletRequest request, ServletResponse response,
    // FilterChain chain) throws IOException, ServletException {
    // System.out.println("Inside the filter");
    // chain.doFilter(request, response);
    // }
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
            throws IOException, ServletException {

        logger.debug("Filtro Autenticazione");

        HttpServletRequest httpRequest = (HttpServletRequest) request;
        HttpServletResponse httpResponse = (HttpServletResponse) response;
        HttpSession session = httpRequest.getSession();

        String requestPath = httpRequest.getServletPath();
        logger.debug("requestPath " + requestPath);

        String user_agent = null;
        String auth = null;

        String workstation = null;
        String domain = null;
        String username = null;

        try {

            if (requestPath != null
                    && (requestPath.endsWith("index.xhtml") || requestPath.endsWith("login.xhtml"))) {
                logger.debug("Richiesta una pagina fra quelle speciali, esco dal filtro");
                chain.doFilter(request, response);
                return;
            } else {

                user_agent = httpRequest.getHeader("user-agent");
                if ((user_agent != null) && (user_agent.indexOf("MSIE") > -1)) {
                    logger.debug("USER-AGENT: " + user_agent);

                    auth = httpRequest.getHeader("Authorization");
                    if (auth == null) {
                        logger.debug("STEP1: SC_UNAUTHORIZED");

                        httpResponse.setStatus(HttpServletResponse.SC_UNAUTHORIZED);
                        httpResponse.setHeader("WWW-Authenticate", "NTLM");
                        httpResponse.flushBuffer();
                        return;
                    }

                    if (auth.startsWith("NTLM ")) {
                        logger.debug("STEP2: NTLM");

                        byte[] msg = org.apache.commons.codec.binary.Base64.decodeBase64(auth.substring(5));
                        // byte[] msg = new
                        // sun.misc.BASE64Decoder().decodeBuffer(auth.substring(5));
                        int off = 0, length, offset;
                        if (msg[8] == 1) {
                            logger.debug("STEP2a: NTLM");

                            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 };
                            // httpResponse.setHeader("WWW-Authenticate",
                            // "NTLM " + new
                            // sun.misc.BASE64Encoder().encodeBuffer(msg1));
                            httpResponse.setHeader("WWW-Authenticate",
                                    "NTLM " + org.apache.commons.codec.binary.Base64.encodeBase64String(msg1));
                            httpResponse.sendError(HttpServletResponse.SC_UNAUTHORIZED);
                            return;
                        } else if (msg[8] == 3) {
                            logger.debug("STEP2b: read data");

                            off = 30;
                            length = msg[off + 17] * 256 + msg[off + 16];
                            offset = msg[off + 19] * 256 + msg[off + 18];
                            workstation = new String(msg, offset, length);

                            length = msg[off + 1] * 256 + msg[off];
                            offset = msg[off + 3] * 256 + msg[off + 2];
                            domain = new String(msg, offset, length);

                            length = msg[off + 9] * 256 + msg[off + 8];
                            offset = msg[off + 11] * 256 + msg[off + 10];
                            username = new String(msg, offset, length);

                            char a = 0;
                            char b = 32;
                            // logger.debug("Username:" +
                            // username.trim().replace(a, b).replaceAll("",
                            // ""));
                            username = username.trim().replace(a, b).replaceAll(" ", "");
                            workstation = workstation.trim().replace(a, b).replaceAll(" ", "");
                            domain = domain.trim().replace(a, b).replaceAll(" ", "");

                            logger.debug("Username: " + username);
                            logger.debug("RemoteHost: " + workstation);
                            logger.debug("Domain: " + domain);

                        }
                    }
                } // if IE
                else {
                    chain.doFilter(request, response);
                }

                String winUser = username; // domain + "\\" + username;

            }
        } catch (RuntimeException e) {
            logger.error("Errore nel Filtro Autenticazione");
            logger.error(e);

            chain.doFilter(request, response);
            httpResponse.sendError(httpResponse.SC_UNAUTHORIZED);

            httpResponse.sendRedirect(httpRequest.getContextPath() + "/index.jsp");
        }

        logger.debug("Fine Filtro Autenticazione");
    }

    public void destroy() {
        logger.debug("");
    }

}