UserPasswordAuthentication.java

/**
 * Copyright 2003-2016 SSHTOOLS Limited. All Rights Reserved.
 *
 * For product documentation visit https://www.sshtools.com/
 *
 * This file is part of J2SSH Maverick.
 *
 * J2SSH Maverick 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.
 *
 * J2SSH Maverick 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with J2SSH Maverick.  If not, see <http://www.gnu.org/licenses/>.
 */
/**
 * This file is originally from the http://sourceforge.net/projects/jsocks/
 * released under the LGPL.
 */
package socks;

/**
  SOCKS5 User Password authentication scheme.
*/
public class UserPasswordAuthentication implements Authentication{

   /**SOCKS ID for User/Password authentication method*/
   public final static int METHOD_ID = 2;

   String userName, password;
   byte[] request;

   /**
     Create an instance of UserPasswordAuthentication.
     @param userName User Name to send to SOCKS server.
     @param password Password to send to SOCKS server.
   */
   public UserPasswordAuthentication(String userName,String password){
     this.userName = userName;
     this.password = password;
     formRequest();
   }
   /** Get the user name.
   @return User name.
   */
   public String getUser(){
     return userName;
   }
   /** Get password
   @return Password
   */
   public String getPassword(){
     return password;
   }
   /**
    Does User/Password authentication as defined in rfc1929.
    @return An array containnig in, out streams, or null if authentication
    fails.
   */
   public Object[] doSocksAuthentication(int methodId,
                                         java.net.Socket proxySocket)
                   throws java.io.IOException{

      if(methodId != METHOD_ID) return null;

      java.io.InputStream in = proxySocket.getInputStream();
      java.io.OutputStream out = proxySocket.getOutputStream();

      out.write(request);
      int version = in.read();
      if(version < 0) return null; //Server closed connection
      int status = in.read();
      if(status != 0) return null; //Server closed connection, or auth failed.

      return new Object[] {in,out};
   }

//Private methods
//////////////////

/** Convert UserName password in to binary form, ready to be send to server*/
   private void formRequest(){
      byte[] user_bytes = userName.getBytes();
      byte[] password_bytes = password.getBytes();

      request = new byte[3+user_bytes.length+password_bytes.length];
      request[0] = (byte) 1; 
      request[1] = (byte) user_bytes.length;
      System.arraycopy(user_bytes,0,request,2,user_bytes.length);
      request[2+user_bytes.length] = (byte) password_bytes.length;
      System.arraycopy(password_bytes,0,
                       request,3+user_bytes.length,password_bytes.length);
   }
}