/*
 * File:       httptrace.java
 * Version:    1.0  08-Jan-2000
 * Author:     Thorsten Sprenger (thorsten@3sprenger.de)
 * Hosted on:  httptrace.sourceforge.org
 *
 */

import java.net.*;
import java.io.*;
import java.util.*;
import java.awt.*;
import java.awt.event.*;

//---------------------------------------------------------------------------
public class httptrace 
extends Frame 
implements ActionListener
{
  static String strVersion = "1.0";
  
  static String strAbout = 
    "\r\nhttptrace - TCP/HTTP trace utility\r\n\r\n"+
    "Usage:  httptrace -help\r\n\r\n"+
    "Version: " +strVersion+ " (see httptrace.sourceforge.org)\r\n"+
    "Author:  Thorsten Sprenger (tsprenger@sourceforge.org)";

  static String strUsage = 
    "\r\nUsage: java httptrace {options}  or Win32 (Microsoft JVM): JVIEW httptrace\r\n"+
    "\r\nOptions are:\r\n"+
    "  -listenport  \tTCP port on which httptrace listens (default: 80)\r\n"+
    "  -tunnelhost  \thostname to which httptrace redirects data  (default: localhost)\r\n"+
    "  -tunnelport  \tport to which httptrace redirects data (default: 80)\r\n"+
    "  -tracefile   \tappend data to this file.\r\n"+
    "               \tuse \"-tracefile stdout\" to write to console.\r\n"+
    "  -pattern     \ttrace only data containing this text (enclosed in \"\")\r\n"+
    "  -nodata      \tdo not trace data\r\n"+
    "  -noheader    \tdo not trace HTTP header\r\n"+
    "  -nodialog    \tdo not display parameter dialog on startup\r\n"+
    "  -nocomments  \tdo not write any comments\r\n"+
    "  -nogui       \tdo not display graphical user interface\r\n"+
    "  -help        \tprint this help\r\n"+
    "  -version     \tprint version\r\n"+
    "\r\nSamples:\r\n"+
    "Listen on port 80 and send requests to www.xyz.com : \r\n"+
    "  java httptrace -tunnelhost www.xyz.com\r\n\r\n"+
    "Listen on port 80 and send requests to local port 81, omit HTTP header : \r\n"+
    "  java httptrace -tunnelport 81 -noheader\r\n\r\n"+
    "Listen on port 80 and send requests to localhost port 6714, but don't display\r\n"+
    "window. Print every packet containing \"<?xml\" on console :\r\n"+
    "  java httptrace -tunnelport 6714 -nogui -pattern \"<?xml\" -tracefile stdout \r\n";
  
  //httptrace parameters:
  static int      iListenPort;
  static int      iTunnelPort;
  static String   strTunnelHost;
  static String   strTraceFile;
  static String   strPattern;
  static boolean  bDisplayData;
  static boolean  bDisplayHttpHeader;
  static boolean  bDisplayComments;
  static boolean  bParameterDialog;
  static boolean  bGui;

  static TextArea taListenText;
  static FileWriter fTrace;
  static DataTunnel inDataTunnel, outDataTunnel;
        
//---------------------------------------------------------------------------
  public httptrace () {    //the constructor inits the main window
  
    if(!bGui) return;      //if no GUI is desired, do not build the frame
    
    Panel p, px;
    ParameterDialog dlg;


    //build main window:     
    setTitle ("httptrace");
    setMenuBar(new MainMenu(this));
    addWindowListener (new WindowAdapter () {
      public void windowClosing (WindowEvent e) {
      	
	System.exit (0);
      }
    });

    setBackground(Color.white);
    setLayout(new BorderLayout(30,30));
    
    add (taListenText = new TextArea ());
    taListenText.setEditable(false);

    pack ();
    show ();
    
    //display parameter dialog:
    if(bParameterDialog) {
      dlg = new ParameterDialog(this);
      dlg.setVisible(true);
    }

    TimeNow t = new TimeNow();
    putComment(1, "httptrace started at " + t.getDateTimeString() );   

    if(!bDisplayHttpHeader) {
      putComment(1, "HTTP headers are not displayed.");
    }
    if(!bDisplayData) {
      putComment(1, "Data is not displayed.");	
    }

    putComment(1, "listenport="+iListenPort+" tunnelhost=" + strTunnelHost+
               " tunnelport="+iTunnelPort);   
    if(strPattern.length() != 0) {
      putComment(1, "searching for pattern: "+strPattern);   
    }
    if(strTraceFile.length() != 0) {
      putComment(1, "writing to file: "+strTraceFile);   
    }
  }

//---------------------------------------------------------------------------
  //print a comment line to text area and trace file.
  //if level=1 then do not print if -nocomments is set
  public void putComment (int level, String txt) {
    if((bDisplayComments) || (level==0)) {
      String s = new String("\r\n> " + txt);
      if (bGui) taListenText.append(s);
      WriteTraceFile(s);      
    }
  }

//---------------------------------------------------------------------------
  //write a string to the tracefile (if -tracefile ist set)
  public void WriteTraceFile(String s) {
    if(strTraceFile.length() != 0) 
    {
      if(strTraceFile.equalsIgnoreCase("stdout")) {
      	System.out.print(s);
      }
      else
      {
        try {
          fTrace = new FileWriter(strTraceFile, true);  //true=append
          fTrace.write(s);
          fTrace.close();
        } catch (IOException e) {
          System.err.println("cannot write to file " + strTraceFile);
          System.err.println(e.toString());
          return;
        }
      }
    }
  }

//---------------------------------------------------------------------------
  //do the menu bar actions:
  public void actionPerformed(ActionEvent event)
  {
    String cmd = event.getActionCommand();
    if(cmd.equals("Exit")) {
      System.exit (0);    	
    } 
    else
    if(cmd.equals("Usage")) {
      putComment(0, strUsage);
    } 
    else
    if(cmd.equals("About")) {
      putComment(0, strAbout);
    } 
    else 
    if(cmd.equals("Clear")) {
      taListenText.setText ("");
    } 
  }


//---------------------------------------------------------------------------
  public static void main (String args[]) throws IOException {
	    
    if( ! processArgs( args ) ) {
      return;
    }
    
    //create the GUI:    
    final httptrace ht = new httptrace ();
    
    // create the server thread:
    Thread threadServer = new Thread () {
      public void run () {
	ServerSocket ss = null;
	try {
	  ss = new ServerSocket (ht.iListenPort);
	} catch (Exception e) {
	  e.printStackTrace ();
	  System.exit (1);
	}
	while (true) {
	  try {
	    // accept the connection from client:
	    Socket sock1 = ss.accept ();
	                       
	    // connect to the thing I'm tunnelling for
	    Socket sock2 = new Socket (ht.strTunnelHost, ht.iTunnelPort);
	    
	    new DataTunnel (ht, sock1.getInputStream (), 
	                        sock2.getOutputStream (),
		                "Request").start ();
	    new DataTunnel (ht, sock2.getInputStream (), 
	                        sock1.getOutputStream (),
		                "Response").start ();
	    
	  } catch (Exception ee) {
	    ee.printStackTrace ();
	  }
	}
      }
    };
    threadServer.start ();
  }

//---------------------------------------------------------------------------
  //read parameters from command line:
  public static boolean processArgs(String[] args) {
    iListenPort        = 80;             //defaults
    strTunnelHost      = "localhost";
    iTunnelPort        = 80;
    strTraceFile       = "";
    strPattern         = "";
    bDisplayHttpHeader = true; 
    bDisplayData       = true;
    bDisplayComments   = true;
    bParameterDialog   = true;
    bGui               = true;
    
    for (int i = 0; i < args.length; i++) {
      String arg = args[i];
	 
      if (arg.equalsIgnoreCase("-help") || 
          arg.equalsIgnoreCase("help") || 
          arg.equalsIgnoreCase("-?") || arg.equalsIgnoreCase("/?")) {
	System.out.println(strUsage);
	return false;
      } else if (arg.equalsIgnoreCase("-listenport")) {
	i++; iListenPort = Integer.parseInt (args[i]);
      } else if (arg.equalsIgnoreCase("-tunnelport")) {
	i++; iTunnelPort = Integer.parseInt (args[i]);
      } else if (arg.equalsIgnoreCase("-tunnelhost")) {
	i++; strTunnelHost = args[i];
      } else if (arg.equalsIgnoreCase("-tracefile")) {
	i++; strTraceFile = args[i];
      } else if (arg.equalsIgnoreCase("-pattern")) {
	i++; strPattern = args[i];
      } else if (arg.equalsIgnoreCase("-nodata")) {
	bDisplayData = false;
      } else if (arg.equalsIgnoreCase("-noheader")) {
	bDisplayHttpHeader = false;
      } else if (arg.equalsIgnoreCase("-nocomments")) {
	bDisplayComments = false;
      } else if (arg.equalsIgnoreCase("-nodialog")) {
	bParameterDialog = false;
      } else if (arg.equalsIgnoreCase("-nogui")) {
	bGui = false;
      } else if (arg.equalsIgnoreCase("-version")) {
	System.out.println(strAbout);
        return false;
      } else {
	System.out.println(strAbout);
        return false;
      }
    }        
    return true;
  }        
}  //end of class httptrace


//---------------------------------------------------------------------------
class MainMenu extends MenuBar {
  public MainMenu(ActionListener listener) {
      Menu m;
      MenuItem mi;
      
      //--------- FILE... -------
      m = new Menu("File");
      
      //--------- EXIT ----------
      mi = new MenuItem("Exit");
      mi.addActionListener (listener);
      m.add(mi);
      
      add(m); 
      
      //--------- VIEW... -------
      m = new Menu("View");
      
      //--------- CLEAR ----------
      mi = new MenuItem("Clear");
      mi.addActionListener (listener);
      m.add(mi);
            
      add(m); 
      	
      //--------- HELP... -------
      m = new Menu("Help");
      
      //--------- USAGE ----------
      mi = new MenuItem("Usage");
      mi.addActionListener (listener);
      m.add(mi);
            
      //--------- ABOUT ----------
      mi = new MenuItem("About");
      mi.addActionListener (listener);
      m.add(mi);
            
      add(m);        	
    }	
}

//---------------------------------------------------------------------------
class ParameterDialog 
extends Dialog
implements ActionListener 
{
  TextField tfiListenPort;
  TextField tfstrTunnelHost;
  TextField tfstrPattern;
  TextField tfstrTraceFile;
  TextField tfiTunnelPort;
  Checkbox  cbDisplayData;
  Checkbox  cbDisplayHttpHeader;
  httptrace ht;
  
  public ParameterDialog(httptrace ht)
  {
    super(ht, "httptrace Parameters:", true);
    Label laOptions;

    this.ht = ht;
    setBackground(Color.lightGray);
    setLayout(new BorderLayout(30,30));
    setResizable(false);
    Point parloc = ht.getLocation();
    setLocation(parloc.x+30,parloc.y+30);

    //Base Parameters:
    Panel p = new Panel ();
    p.setLayout (new GridLayout (4,2,3,0));
    p.add (new Label (""));
    p.add (new Label (""));
    p.add (new Label ("Listen on Port: "));
    tfiListenPort = new TextField(Integer.toString(ht.iListenPort),6);
    p.add(tfiListenPort);
    p.add (new Label ("Tunnel to Host: "));
    tfstrTunnelHost = new TextField(ht.strTunnelHost);
    p.add(tfstrTunnelHost);
    p.add (new Label ("Tunnel to Port: "));
    tfiTunnelPort = new TextField(Integer.toString(ht.iTunnelPort),6);
    p.add(tfiTunnelPort);
    add ("North", p);

    //Optional Parameters:
    Panel pOpt = new Panel ();
    pOpt.setLayout (new GridLayout (6,2,3,0));
    pOpt.add (new Label (""));
    pOpt.add (new Label (""));
    laOptions = new Label ("Options:");  
    pOpt.add (laOptions);
    
    pOpt.add (new Label (""));
    pOpt.add (new Label ("Display Data: "));
    cbDisplayData = new Checkbox("",ht.bDisplayData);
    pOpt.add(cbDisplayData);
    pOpt.add (new Label ("Display HTTP Header: "));
    cbDisplayHttpHeader = new Checkbox("",ht.bDisplayHttpHeader);
    pOpt.add(cbDisplayHttpHeader);
    pOpt.add (new Label ("Search Pattern:"));
    tfstrPattern = new TextField(ht.strPattern);
    pOpt.add(tfstrPattern);
    pOpt.add (new Label ("Write to File:"));
    tfstrTraceFile = new TextField(ht.strTraceFile);
    pOpt.add(tfstrTraceFile);
    add("Center", pOpt);	

    Button bOK = new Button("OK");
    bOK.addActionListener(this);
    add("South", bOK);	
    pack();
  }
  
  public void actionPerformed(ActionEvent event)
  {
    String cmd = event.getActionCommand();
    if(cmd.equals("OK")) {
      setVisible(false);

      ht.iListenPort   = Integer.parseInt(tfiListenPort.getText().trim() );
      ht.strTunnelHost = tfstrTunnelHost.getText().trim();
      ht.strPattern    = tfstrPattern.getText();
      ht.strTraceFile  = tfstrTraceFile.getText();
      ht.iTunnelPort   = Integer.parseInt(tfiTunnelPort.getText().trim() );
      ht.bDisplayHttpHeader = cbDisplayHttpHeader.getState();
      ht.bDisplayData  = cbDisplayData.getState();
	
      dispose();  //close parameter dialog
    }     	
  }
}


//---------------------------------------------------------------------------
class TimeNow
{
  GregorianCalendar cal;            
  String strTime;
  
  TimeNow() {
    cal = new GregorianCalendar();
  }
  
  public String getDateTimeString() {
    strTime = cal.get(Calendar.YEAR)        + "/" + 
              cal.get(Calendar.MONTH)       + "/" +
              cal.get(Calendar.DATE)        + " " +
              cal.get(Calendar.HOUR_OF_DAY) + ":" +
              cal.get(Calendar.MINUTE)      + ":" +
              cal.get(Calendar.SECOND);
    return(strTime);
  }

  public String getTimeString() {
    strTime = cal.get(Calendar.HOUR_OF_DAY) + ":" +
              cal.get(Calendar.MINUTE)      + ":" +
              cal.get(Calendar.SECOND);
    return(strTime);
  }
}


//---------------------------------------------------------------------------
//this thread is started twice: 
//one thread for the client request, the other for the server response.
class DataTunnel extends Thread {
  final static int BUFSIZ = 1000;
  InputStream in;
  OutputStream out;
  byte buf[] = new byte[BUFSIZ];
  String direction;
  TextArea ta;
  httptrace ht;

  DataTunnel (httptrace ht,InputStream in,OutputStream out,String direction) 
  {
    this.ht = ht;
    this.in = in;
    this.out = out;
    this.direction = direction;
    this.ta = ta;
  }

  public void run () {
    int n;
    int iHttpHeaderEnd;  //position of HTTP header end in packet
    int iDataPos;        //postition of HTTP data start in packet
    boolean bHttpHeader;
    String s;
    String strBuf;

    iDataPos = 0;
    try {
      while ((n = in.read (buf)) > 0) {
      		
	//write to TCPIP port:
	out.write (buf, 0, n);
	out.flush ();
        iDataPos = 0;
          
          //is HTTP header in buffer?
	strBuf = new String (buf, 0, n);
	if(strBuf.indexOf("HTTP/1") != -1)
	  bHttpHeader = true;
	else
	  bHttpHeader = false;
		
	//do this only on start of a HTTP transaction:
	//iDataPos marks the begin of HTTP data (after HTTP header):
	if(bHttpHeader) {        
	  bHttpHeader = false;  
	  
	  //display time stamp:  
          TimeNow t = new TimeNow();
          ht.putComment(1, "\r\n---- HTTP " +
             direction + " at " + t.getTimeString() + 
             " ----\r\n");

          //search for end of HTTP header (2 line feeds):
	  strBuf = new String (buf, 0, n);
	  iHttpHeaderEnd = strBuf.indexOf("\n\n");
	  if(iHttpHeaderEnd == -1) {
	    //if not found, try again with DOS line feeds:
  	    iHttpHeaderEnd = strBuf.indexOf("\r\n\r\n");
	  }
	  if(iHttpHeaderEnd == -1) 
	    iDataPos = 0;  // if no HTTP header end, 
	  else                // then display all from start
	    iDataPos = iHttpHeaderEnd + 2;
	}

        s = "";
        if(!ht.bDisplayHttpHeader && ht.bDisplayData) //display no HTTP header, only data
        {
  	  s = new String (buf, iDataPos, n);
  	}
  	 
        if(ht.bDisplayHttpHeader && !ht.bDisplayData) //display no data, only header
        {
  	  s = new String (buf, 0, iDataPos);            
  	}

        if(ht.bDisplayHttpHeader && ht.bDisplayData)  //display both header and data
  	{                          
  	  s = new String (buf, 0, n);
  	}

        //only if there is a search pattern, search for it.
	if((ht.strPattern.length() == 0) || (strBuf.indexOf(ht.strPattern) != -1))
	{
	  if(ht.bGui) ht.taListenText.append (s);     //write to TextArea
          ht.WriteTraceFile(s);                       //write to file
	}
	  
	iDataPos = 0;  //after header packet:
	               //for all following packets, display whole packet
      }
    } catch (IOException e) {} 
    finally {
      try {
	in.close ();
	out.close ();
      } catch (IOException e) {}
    }
  }
}

//---------------------------------------------------------------------------
//end of httptrace.java