--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/net/sourceforge/jsocks/server/ServerAuthenticatorNone.java	Thu May 22 10:41:19 2014 -0700
@@ -0,0 +1,169 @@
+package net.sourceforge.jsocks.server;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.io.PushbackInputStream;
+import java.net.Socket;
+
+import net.sourceforge.jsocks.ProxyMessage;
+import net.sourceforge.jsocks.UDPEncapsulation;
+
+/**
+ An implementation of ServerAuthenticator, which does <b>not</b> do
+ any authentication.
+<P>
+<FONT size="+3" color ="FF0000"> Warning!!</font><br> Should not be
+used on machines which are not behind the firewall.
+<p>
+It is only provided to make implementing other authentication schemes
+easier.<br>
+For Example: <tt><pre>
+   class MyAuth extends socks.server.ServerAuthenticator{
+    ...
+    public ServerAuthenticator startSession(java.net.Socket s){
+      if(!checkHost(s.getInetAddress()) return null;
+      return super.startSession(s);
+    }
+
+    boolean checkHost(java.net.Inetaddress addr){
+      boolean allow;
+      //Do it somehow
+      return allow;
+    }
+   }
+</pre></tt>
+*/
+public class ServerAuthenticatorNone implements ServerAuthenticator {
+
+    static final byte[] socks5response = {5, 0};
+
+    InputStream in;
+    OutputStream out;
+
+    /**
+     Creates new instance of the ServerAuthenticatorNone.
+    */
+    public ServerAuthenticatorNone() {
+        this.in = null;
+        this.out = null;
+    }
+    /**
+     Constructs new ServerAuthenticatorNone object suitable for returning
+     from the startSession function.
+     @param in Input stream to return from getInputStream method.
+     @param out Output stream to return from getOutputStream method.
+    */
+    public ServerAuthenticatorNone(InputStream in, OutputStream out) {
+        this.in = in;
+        this.out = out;
+    }
+    /**
+     Grants access to everyone.Removes authentication related bytes from
+     the stream, when a SOCKS5 connection is being made, selects an
+     authentication NONE.
+     */
+    public ServerAuthenticator startSession(Socket s)
+    throws IOException {
+        PushbackInputStream in =  new PushbackInputStream(s.getInputStream());
+        OutputStream out = s.getOutputStream();
+        int version = in.read();
+
+        if (version == 5) {
+            if (!selectSocks5Authentication(in, out, 0))
+                return null;
+        }
+        else if (version == 4) {
+            //Else it is the request message allready, version 4
+            in.unread(version);
+        }
+        else
+            return null;
+
+        return new ServerAuthenticatorNone(in, out);
+    }
+
+    /**
+      Get input stream.
+      @return Input stream speciefied in the constructor.
+    */
+    public InputStream getInputStream() {
+        return in;
+    }
+    /**
+      Get output stream.
+      @return Output stream speciefied in the constructor.
+    */
+    public OutputStream getOutputStream() {
+        return out;
+    }
+    /**
+      Allways returns null.
+      @return null
+    */
+    public UDPEncapsulation getUdpEncapsulation() {
+        return null;
+    }
+
+    /**
+     Allways returns true.
+    */
+    public boolean checkRequest(ProxyMessage msg) {
+        return true;
+    }
+
+    /**
+     Allways returns true.
+    */
+    public boolean checkRequest(java.net.DatagramPacket dp, boolean out) {
+        return true;
+    }
+
+    /**
+     Does nothing.
+     */
+    public void endSession() {
+    }
+
+    /**
+      Convinience routine for selecting SOCKSv5 authentication.
+      <p>
+      This method reads in authentication methods that client supports,
+      checks wether it supports given method. If it does, the notification
+      method is written back to client, that this method have been chosen
+      for authentication. If given method was not found, authentication
+      failure message is send to client ([5,FF]).
+      @param in Input stream, version byte should be removed from the stream
+                before calling this method.
+      @param out Output stream.
+      @param methodId Method which should be selected.
+      @return true if methodId was found, false otherwise.
+    */
+    static public boolean selectSocks5Authentication(InputStream in,
+            OutputStream out,
+            int methodId)
+    throws IOException {
+        int num_methods = in.read();
+
+        if (num_methods <= 0) return false;
+
+        byte method_ids[] = new byte[num_methods];
+        byte response[] = new byte[2];
+        boolean found = false;
+        response[0] = (byte) 5;    //SOCKS version
+        response[1] = (byte) 0xFF; //Not found, we are pessimistic
+        int bread = 0; //bytes read so far
+
+        while (bread < num_methods)
+            bread += in.read(method_ids, bread, num_methods - bread);
+
+        for (int i = 0; i < num_methods; ++i)
+            if (method_ids[i] == methodId) {
+                found = true;
+                response[1] = (byte) methodId;
+                break;
+            }
+
+        out.write(response);
+        return found;
+    }
+}