java/com/tigervnc/vncviewer/tunnel.java - android_external_tigervnc - Gitiles

 /*
  *  Copyright (C) 2012 Brian P. Hinz.  All Rights Reserved.
  *  Copyright (C) 2000 Const Kaplinsky.  All Rights Reserved.
  *  Copyright (C) 1999 AT&T Laboratories Cambridge.  All Rights Reserved.
  *
  *  This is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
  *  the Free Software Foundation; either version 2 of the License, or
  *  (at your option) any later version.
  *
  *  This software 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 this software; if not, write to the Free Software
  *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
  *  USA.
  */

 /*
  * tunnel.java - SSH tunneling support
  */

 package com.tigervnc.vncviewer;

 import java.io.File;
 import java.lang.Character;
 import java.util.ArrayList;
 import java.util.Iterator;

 import com.tigervnc.rdr.*;
 import com.tigervnc.rfb.*;
 import com.tigervnc.network.*;

 import com.jcraft.jsch.JSch;
 import com.jcraft.jsch.Session;

 public class tunnel
 {
   private final static Integer SERVER_PORT_OFFSET = 5900;;
   private final static String DEFAULT_SSH_CMD = "/usr/bin/ssh";
   private final static String DEFAULT_TUNNEL_CMD
     = DEFAULT_SSH_CMD+" -f -L %L:localhost:%R %H sleep 20";
   private final static String DEFAULT_VIA_CMD
     = DEFAULT_SSH_CMD+" -f -L %L:%H:%R %G sleep 20";

   private final static int H = 17;
   private final static int G = 16;
   private final static int R = 27;
   private final static int L = 21;

   /* True if there was -tunnel or -via option in the command line. */
   private static boolean tunnelSpecified = false;

   /* True if it was -tunnel, not -via option. */
   private static boolean tunnelOption = false;

   /* "Hostname:display" pair in the command line will be substituted
      by this fake argument when tunneling is used. */
   private static String lastArgv;

   private static String tunnelEndpoint;

   public static Boolean
   createTunnel(int pargc, String[] argv, int tunnelArgIndex)
   {
     char[] pattern;
     char[] cmd = new char[1024];
     int[] localPort = new int[1];
     int[] remotePort = new int[1];
     char[] localPortStr = new char[8];
     char[] remotePortStr = new char[8];
     StringBuilder gatewayHost = new StringBuilder("");
     StringBuilder remoteHost = new StringBuilder("localhost");

     tunnelSpecified = true;
     if (argv[tunnelArgIndex].equalsIgnoreCase("-tunnel"))
       tunnelOption = true;

     pattern = getCmdPattern();
     if (pattern == null)
       return false;

     localPort[0] = TcpSocket.findFreeTcpPort();
     if (localPort[0] == 0)
       return false;

     if (tunnelOption) {
       processTunnelArgs(remoteHost, remotePort, localPort,
   		      pargc, argv, tunnelArgIndex);
     } else {
       processViaArgs(gatewayHost, remoteHost, remotePort, localPort,
   		   pargc, argv, tunnelArgIndex);
     }

     localPortStr = Integer.toString(localPort[0]).toCharArray();
     remotePortStr = Integer.toString(remotePort[0]).toCharArray();

     if (!fillCmdPattern(cmd, pattern, gatewayHost.toString().toCharArray(),
 		remoteHost.toString().toCharArray(), remotePortStr, localPortStr))
       return false;

     if (!runCommand(new String(cmd)))
       return false;

     return true;
   }

   private static void
   processTunnelArgs(StringBuilder remoteHost, int[] remotePort,
                     int[] localPort, int pargc, String[] argv,
                     int tunnelArgIndex)
   {
     String pdisplay;

     if (tunnelArgIndex >= pargc - 1)
       VncViewer.usage();

     pdisplay = argv[pargc - 1].split(":")[1];
     if (pdisplay == null || pdisplay == argv[pargc - 1])
       VncViewer.usage();

     if (pdisplay.matches("/[^0-9]/"))
       VncViewer.usage();

     remotePort[0] = Integer.parseInt(pdisplay);
     if (remotePort[0] < 100)
       remotePort[0] = remotePort[0] + SERVER_PORT_OFFSET;

     lastArgv = new String("localhost::"+localPort[0]);

     remoteHost.setLength(0);
     remoteHost.insert(0, argv[pargc - 1].split(":")[0]);
     argv[pargc - 1] = lastArgv;

     //removeArgs(pargc, argv, tunnelArgIndex, 1);
   }

   private static void
   processViaArgs(StringBuilder gatewayHost, StringBuilder remoteHost,
   	       int[] remotePort, int[] localPort,
   	       int pargc, String[] argv, int tunnelArgIndex)
   {
     String colonPos;
     int len, portOffset;
     int disp;

     if (tunnelArgIndex >= pargc - 2)
       VncViewer.usage();

     colonPos = argv[pargc - 1].split(":", 2)[1];
     if (colonPos == null) {
       /* No colon -- use default port number */
       remotePort[0] = SERVER_PORT_OFFSET;
     } else {
       len = colonPos.length();
       portOffset = SERVER_PORT_OFFSET;
       if (colonPos.startsWith(":")) {
         /* Two colons -- interpret as a port number */
         colonPos.replaceFirst(":", "");
         len--;
         portOffset = 0;
       }
       if (len == 0 || colonPos.matches("/[^0-9]/")) {
         VncViewer.usage();
       }
       disp = Integer.parseInt(colonPos);
       if (portOffset != 0 && disp >= 100)
         portOffset = 0;
       remotePort[0] = disp + portOffset;
     }

     lastArgv = "localhost::"+localPort[0];

     gatewayHost.setLength(0);
     gatewayHost.insert(0, argv[tunnelArgIndex + 1]);

     if (!argv[pargc - 1].split(":", 2)[0].equals("")) {
       remoteHost.setLength(0);
       remoteHost.insert(0, argv[pargc - 1].split(":", 2)[0]);
     }

     argv[pargc - 1] = lastArgv;

     //removeArgs(pargc, argv, tunnelArgIndex, 2);
   }

   private static char[]
   getCmdPattern()
   {
     String pattern = "";

     try {
       if (tunnelOption) {
         pattern = System.getProperty("VNC_TUNNEL_CMD");
       } else {
         pattern = System.getProperty("VNC_VIA_CMD");
       }
     } catch (java.lang.Exception e) {
       vlog.info(e.toString());
     }
     if (pattern == null || pattern.equals(""))
       pattern = (tunnelOption) ? DEFAULT_TUNNEL_CMD : DEFAULT_VIA_CMD;

     return pattern.toCharArray();
   }

   /* Note: in fillCmdPattern() result points to a 1024-byte buffer */

   private static boolean
   fillCmdPattern(char[] result, char[] pattern,
   	       char[] gatewayHost, char[] remoteHost,
   	       char[] remotePort, char[] localPort)
   {
     int i, j;
     boolean H_found = false, G_found = false, R_found = false, L_found = false;

     for (i=0, j=0; i < pattern.length && j<1023; i++, j++) {
       if (pattern[i] == '%') {
         switch (pattern[++i]) {
         case 'H':
   	System.arraycopy(remoteHost, 0, result, j, remoteHost.length);
   	j += remoteHost.length;
   	H_found = true;
         tunnelEndpoint = new String(remoteHost);
   	continue;
         case 'G':
   	System.arraycopy(gatewayHost, 0, result, j, gatewayHost.length);
   	j += gatewayHost.length;
   	G_found = true;
         tunnelEndpoint = new String(gatewayHost);
   	continue;
         case 'R':
   	System.arraycopy(remotePort, 0, result, j, remotePort.length);
   	j += remotePort.length;
   	R_found = true;
   	continue;
         case 'L':
   	System.arraycopy(localPort, 0, result, j, localPort.length);
   	j += localPort.length;
   	L_found = true;
   	continue;
         case '\0':
   	i--;
   	continue;
         }
       }
       result[j] = pattern[i];
     }

     if (pattern.length > 1024) {
       vlog.error("Tunneling command is too long.");
       return false;
     }

     if (!H_found || !R_found || !L_found) {
       vlog.error("%H, %R or %L absent in tunneling command.");
       return false;
     }
     if (!tunnelOption && !G_found) {
       vlog.error("%G pattern absent in tunneling command.");
       return false;
     }

     return true;
   }

   private static Boolean
   runCommand(String cmd)
   {
     try{
       JSch jsch=new JSch();
       String homeDir = new String("");
       try {
         homeDir = System.getProperty("user.home");
       } catch(java.security.AccessControlException e) {
         System.out.println("Cannot access user.home system property");
       }
       // NOTE: jsch does not support all ciphers.  User may be
       //       prompted to accept host key authenticy even if
       //       the key is in the known_hosts file.
       File knownHosts = new File(homeDir+"/.ssh/known_hosts");
       if (knownHosts.exists() && knownHosts.canRead())
 	      jsch.setKnownHosts(knownHosts.getAbsolutePath());
       ArrayList<File> privateKeys = new ArrayList<File>();
       privateKeys.add(new File(homeDir+"/.ssh/id_rsa"));
       privateKeys.add(new File(homeDir+"/.ssh/id_dsa"));
       for (Iterator<File> i = privateKeys.iterator(); i.hasNext();) {
         File privateKey = (File)i.next();
         if (privateKey.exists() && privateKey.canRead())
 	        jsch.addIdentity(privateKey.getAbsolutePath());
       }
       // username and passphrase will be given via UserInfo interface.
       PasswdDialog dlg = new PasswdDialog(new String("SSH Authentication"), false, false);
       dlg.promptPassword(new String("SSH Authentication"));

       Session session=jsch.getSession(dlg.userEntry.getText(), tunnelEndpoint, 22);
       session.setPassword(new String(dlg.passwdEntry.getPassword()));
       session.connect();

       String[] tokens = cmd.split("\\s");
       for (int i = 0; i < tokens.length; i++) {
         if (tokens[i].equals("-L")) {
           String[] par = tokens[++i].split(":");
           int localPort = Integer.parseInt(par[0].trim());
           String remoteHost = par[1].trim();
           int remotePort = Integer.parseInt(par[2].trim());
           session.setPortForwardingL(localPort, remoteHost, remotePort);
         } else if (tokens[i].equals("-R")) {
           String[] par = tokens[++i].split(":");
           int remotePort = Integer.parseInt(par[0].trim());
           String localHost = par[1].trim();
           int localPort = Integer.parseInt(par[2].trim());
           session.setPortForwardingR(remotePort, localHost, localPort);
         }
       }
     } catch (java.lang.Exception e) {
       System.out.println(" Tunneling command failed: "+e.toString());
       return false;
     }
     return true;
   }

   static LogWriter vlog = new LogWriter("tunnel");
 }
	/*
	* Copyright (C) 2012 Brian P. Hinz. All Rights Reserved.
	* Copyright (C) 2000 Const Kaplinsky. All Rights Reserved.
	* Copyright (C) 1999 AT&T Laboratories Cambridge. All Rights Reserved.
	*
	* This is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; either version 2 of the License, or
	* (at your option) any later version.
	*
	* This software 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 this software; if not, write to the Free Software
	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
	* USA.
	*/

	/*
	* tunnel.java - SSH tunneling support
	*/

	package com.tigervnc.vncviewer;

	import java.io.File;
	import java.lang.Character;
	import java.util.ArrayList;
	import java.util.Iterator;

	import com.tigervnc.rdr.*;
	import com.tigervnc.rfb.*;
	import com.tigervnc.network.*;

	import com.jcraft.jsch.JSch;
	import com.jcraft.jsch.Session;

	public class tunnel
	{
	private final static Integer SERVER_PORT_OFFSET = 5900;;
	private final static String DEFAULT_SSH_CMD = "/usr/bin/ssh";
	private final static String DEFAULT_TUNNEL_CMD
	= DEFAULT_SSH_CMD+" -f -L %L:localhost:%R %H sleep 20";
	private final static String DEFAULT_VIA_CMD
	= DEFAULT_SSH_CMD+" -f -L %L:%H:%R %G sleep 20";

	private final static int H = 17;
	private final static int G = 16;
	private final static int R = 27;
	private final static int L = 21;

	/* True if there was -tunnel or -via option in the command line. */
	private static boolean tunnelSpecified = false;

	/* True if it was -tunnel, not -via option. */
	private static boolean tunnelOption = false;

	/* "Hostname:display" pair in the command line will be substituted
	by this fake argument when tunneling is used. */
	private static String lastArgv;

	private static String tunnelEndpoint;

	public static Boolean
	createTunnel(int pargc, String[] argv, int tunnelArgIndex)
	{
	char[] pattern;
	char[] cmd = new char[1024];
	int[] localPort = new int[1];
	int[] remotePort = new int[1];
	char[] localPortStr = new char[8];
	char[] remotePortStr = new char[8];
	StringBuilder gatewayHost = new StringBuilder("");
	StringBuilder remoteHost = new StringBuilder("localhost");

	tunnelSpecified = true;
	if (argv[tunnelArgIndex].equalsIgnoreCase("-tunnel"))
	tunnelOption = true;

	pattern = getCmdPattern();
	if (pattern == null)
	return false;

	localPort[0] = TcpSocket.findFreeTcpPort();
	if (localPort[0] == 0)
	return false;

	if (tunnelOption) {
	processTunnelArgs(remoteHost, remotePort, localPort,
	pargc, argv, tunnelArgIndex);
	} else {
	processViaArgs(gatewayHost, remoteHost, remotePort, localPort,
	pargc, argv, tunnelArgIndex);
	}

	localPortStr = Integer.toString(localPort[0]).toCharArray();
	remotePortStr = Integer.toString(remotePort[0]).toCharArray();

	if (!fillCmdPattern(cmd, pattern, gatewayHost.toString().toCharArray(),
	remoteHost.toString().toCharArray(), remotePortStr, localPortStr))
	return false;

	if (!runCommand(new String(cmd)))
	return false;

	return true;
	}

	private static void
	processTunnelArgs(StringBuilder remoteHost, int[] remotePort,
	int[] localPort, int pargc, String[] argv,
	int tunnelArgIndex)
	{
	String pdisplay;

	if (tunnelArgIndex >= pargc - 1)
	VncViewer.usage();

	pdisplay = argv[pargc - 1].split(":")[1];
	if (pdisplay == null \|\| pdisplay == argv[pargc - 1])
	VncViewer.usage();

	if (pdisplay.matches("/[^0-9]/"))
	VncViewer.usage();

	remotePort[0] = Integer.parseInt(pdisplay);
	if (remotePort[0] < 100)
	remotePort[0] = remotePort[0] + SERVER_PORT_OFFSET;

	lastArgv = new String("localhost::"+localPort[0]);

	remoteHost.setLength(0);
	remoteHost.insert(0, argv[pargc - 1].split(":")[0]);
	argv[pargc - 1] = lastArgv;

	//removeArgs(pargc, argv, tunnelArgIndex, 1);
	}

	private static void
	processViaArgs(StringBuilder gatewayHost, StringBuilder remoteHost,
	int[] remotePort, int[] localPort,
	int pargc, String[] argv, int tunnelArgIndex)
	{
	String colonPos;
	int len, portOffset;
	int disp;

	if (tunnelArgIndex >= pargc - 2)
	VncViewer.usage();

	colonPos = argv[pargc - 1].split(":", 2)[1];
	if (colonPos == null) {
	/* No colon -- use default port number */
	remotePort[0] = SERVER_PORT_OFFSET;
	} else {
	len = colonPos.length();
	portOffset = SERVER_PORT_OFFSET;
	if (colonPos.startsWith(":")) {
	/* Two colons -- interpret as a port number */
	colonPos.replaceFirst(":", "");
	len--;
	portOffset = 0;
	}
	if (len == 0 \|\| colonPos.matches("/[^0-9]/")) {
	VncViewer.usage();
	}
	disp = Integer.parseInt(colonPos);
	if (portOffset != 0 && disp >= 100)
	portOffset = 0;
	remotePort[0] = disp + portOffset;
	}

	lastArgv = "localhost::"+localPort[0];

	gatewayHost.setLength(0);
	gatewayHost.insert(0, argv[tunnelArgIndex + 1]);

	if (!argv[pargc - 1].split(":", 2)[0].equals("")) {
	remoteHost.setLength(0);
	remoteHost.insert(0, argv[pargc - 1].split(":", 2)[0]);
	}

	argv[pargc - 1] = lastArgv;

	//removeArgs(pargc, argv, tunnelArgIndex, 2);
	}

	private static char[]
	getCmdPattern()
	{
	String pattern = "";

	try {
	if (tunnelOption) {
	pattern = System.getProperty("VNC_TUNNEL_CMD");
	} else {
	pattern = System.getProperty("VNC_VIA_CMD");
	}
	} catch (java.lang.Exception e) {
	vlog.info(e.toString());
	}
	if (pattern == null \|\| pattern.equals(""))
	pattern = (tunnelOption) ? DEFAULT_TUNNEL_CMD : DEFAULT_VIA_CMD;

	return pattern.toCharArray();
	}

	/* Note: in fillCmdPattern() result points to a 1024-byte buffer */

	private static boolean
	fillCmdPattern(char[] result, char[] pattern,
	char[] gatewayHost, char[] remoteHost,
	char[] remotePort, char[] localPort)
	{
	int i, j;
	boolean H_found = false, G_found = false, R_found = false, L_found = false;

	for (i=0, j=0; i < pattern.length && j<1023; i++, j++) {
	if (pattern[i] == '%') {
	switch (pattern[++i]) {
	case 'H':
	System.arraycopy(remoteHost, 0, result, j, remoteHost.length);
	j += remoteHost.length;
	H_found = true;
	tunnelEndpoint = new String(remoteHost);
	continue;
	case 'G':
	System.arraycopy(gatewayHost, 0, result, j, gatewayHost.length);
	j += gatewayHost.length;
	G_found = true;
	tunnelEndpoint = new String(gatewayHost);
	continue;
	case 'R':
	System.arraycopy(remotePort, 0, result, j, remotePort.length);
	j += remotePort.length;
	R_found = true;
	continue;
	case 'L':
	System.arraycopy(localPort, 0, result, j, localPort.length);
	j += localPort.length;
	L_found = true;
	continue;
	case '\0':
	i--;
	continue;
	}
	}
	result[j] = pattern[i];
	}

	if (pattern.length > 1024) {
	vlog.error("Tunneling command is too long.");
	return false;
	}

	if (!H_found \|\| !R_found \|\| !L_found) {
	vlog.error("%H, %R or %L absent in tunneling command.");
	return false;
	}
	if (!tunnelOption && !G_found) {
	vlog.error("%G pattern absent in tunneling command.");
	return false;
	}

	return true;
	}

	private static Boolean
	runCommand(String cmd)
	{
	try{
	JSch jsch=new JSch();
	String homeDir = new String("");
	try {
	homeDir = System.getProperty("user.home");
	} catch(java.security.AccessControlException e) {
	System.out.println("Cannot access user.home system property");
	}
	// NOTE: jsch does not support all ciphers. User may be
	// prompted to accept host key authenticy even if
	// the key is in the known_hosts file.
	File knownHosts = new File(homeDir+"/.ssh/known_hosts");
	if (knownHosts.exists() && knownHosts.canRead())
	jsch.setKnownHosts(knownHosts.getAbsolutePath());
	ArrayList<File> privateKeys = new ArrayList<File>();
	privateKeys.add(new File(homeDir+"/.ssh/id_rsa"));
	privateKeys.add(new File(homeDir+"/.ssh/id_dsa"));
	for (Iterator<File> i = privateKeys.iterator(); i.hasNext();) {
	File privateKey = (File)i.next();
	if (privateKey.exists() && privateKey.canRead())
	jsch.addIdentity(privateKey.getAbsolutePath());
	}
	// username and passphrase will be given via UserInfo interface.
	PasswdDialog dlg = new PasswdDialog(new String("SSH Authentication"), false, false);
	dlg.promptPassword(new String("SSH Authentication"));

	Session session=jsch.getSession(dlg.userEntry.getText(), tunnelEndpoint, 22);
	session.setPassword(new String(dlg.passwdEntry.getPassword()));
	session.connect();

	String[] tokens = cmd.split("\\s");
	for (int i = 0; i < tokens.length; i++) {
	if (tokens[i].equals("-L")) {
	String[] par = tokens[++i].split(":");
	int localPort = Integer.parseInt(par[0].trim());
	String remoteHost = par[1].trim();
	int remotePort = Integer.parseInt(par[2].trim());
	session.setPortForwardingL(localPort, remoteHost, remotePort);
	} else if (tokens[i].equals("-R")) {
	String[] par = tokens[++i].split(":");
	int remotePort = Integer.parseInt(par[0].trim());
	String localHost = par[1].trim();
	int localPort = Integer.parseInt(par[2].trim());
	session.setPortForwardingR(remotePort, localHost, localPort);
	}
	}
	} catch (java.lang.Exception e) {
	System.out.println(" Tunneling command failed: "+e.toString());
	return false;
	}
	return true;
	}

	static LogWriter vlog = new LogWriter("tunnel");
	}