src/java/com/oroinc/net/bsd/RLoginClient.java

/***
 * $Id: RLoginClient.java,v 1.1 2002/04/03 01:04:40 brekke Exp $
 *
 * NetComponents Internet Protocol Library
 * Copyright (C) 1997-2002  Daniel F. Savarese
 *
 * This library 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 2.1 of the License, or (at your option) any later version.
 *
 * This library 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 this library in the LICENSE file; if not, write
 * to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
 * Boston, MA  02111-1307  USA
 ***/

package com.oroinc.net.bsd;

import java.io.*;

/***
 * RLoginClient is very similar to
 * <a href="com.oroinc.net.bsd.RCommandClient.html"> RCommandClient </a>,
 * from which it is derived, and uses the rcmd() facility implemented
 * in RCommandClient to implement the functionality of the rlogin command that
 * first appeared in 4.2BSD Unix.  rlogin is a command used to login to
 * a remote machine from a trusted host, sometimes without issuing a
 * password.  The trust relationship is the same as described in
 * the documentation for
 * <a href="com.oroinc.net.bsd.RCommandClient.html"> RCommandClient </a>.
 * <p>
 * As with virtually all of the client classes in com.oroinc.net, this
 * class derives from SocketClient.  But it relies on the connection
 * methods defined  in RcommandClient which ensure that the local Socket
 * will originate from an acceptable rshell port.  The way to use 
 * RLoginClient is to first connect
 * to the server, call the <a href="#rlogin"> rlogin() </a> method,
 * and then
 * fetch the connection's input and output streams.
 * Interaction with the remote command is controlled entirely through the
 * I/O streams.  Once you have finished processing the streams, you should
 * invoke <a href="com.oroinc.net.bsd.RExecClient.html#disconnect"> 
 * disconnect() </a> to clean up properly.
 * <p>
 * The standard output and standard error streams of the
 * remote process are transmitted over the same connection, readable
 * from the input stream returned by
 * <a href="com.oroinc.net.bsd.RExecClient.html#getInputStream">
 * getInputStream() </a>.  Unlike RExecClient and RCommandClient, it is
 * not possible to tell the rlogind daemon to return the standard error
 * stream over a separate connection.
 * <a href="com.oroinc.net.bsd.RExecClient.html#getErrorStream">
 * getErrorStream() </a> will always return null.
 * The standard input of the remote process can be written to through
 * the output stream returned by 
 * <a href="com.oroinc.net.bsd.RExecClient.html#getOutputStream"> 
 * getOutputSream() </a>.
 * <p>
 * <p>
 * @author Daniel F. Savarese
 * @see com.oroinc.net.SocketClient
 * @see RExecClient
 * @see RCommandClient
 ***/

public class RLoginClient extends RCommandClient {
  /***
   * The default rlogin port.  Set to 513 in BSD Unix and according 
   * to RFC 1282.
   ***/
  public static final int DEFAULT_PORT    = 513;

  /***
   * The default RLoginClient constructor.  Initializes the
   * default port to <code> DEFAULT_PORT </code>.
   ***/
  public RLoginClient() {
    setDefaultPort(DEFAULT_PORT);
  }


  /***
   * Logins into a remote machine through the rlogind daemon on the server
   * to which the RLoginClient is connected.  After calling this method,
   * you may interact with the remote login shell through its standard input
   * and output streams.  Standard error is sent over the same stream as
   * standard output.  You will typically be able to detect
   * the termination of the remote login shell after reaching end of file
   * on its standard output (accessible through
   * <a href="#getInputStream"> getInputStream() </a>.  Disconnecting
   * from the server or closing the process streams before reaching
   * end of file will terminate the remote login shell in most cases.
   * <p>
   * If user authentication fails, the rlogind daemon will request that
   * a password be entered interactively.  You will be able to read the
   * prompt from the output stream of the RLoginClient and write the
   * password to the input stream of the RLoginClient.
   * <p>
   * @param localUsername  The user account on the local machine that is
   *        trying to login to the remote host.
   * @param remoteUsername  The account name on the server that is
   *        being logged in to.
   * @param terminalType   The name of the user's terminal (e.g., "vt100",
   *        "network", etc.)
   * @param terminalSpeed  The speed of the user's terminal, expressed
   *        as a baud rate or bps (e.g., 9600 or 38400)
   * @exception IOException If the rlogin() attempt fails.  The exception
   *            will contain a message indicating the nature of the failure.
   ***/
  public void rlogin(String localUsername, String remoteUsername,
		     String terminalType, int terminalSpeed)
       throws IOException
  {
    rexec(localUsername, remoteUsername, terminalType + "/" + terminalSpeed,
	  false);
  }

  /***
   * Same as the other rlogin method, but no terminal speed is defined.
   ***/
  public void rlogin(String localUsername, String remoteUsername,
		     String terminalType)
       throws IOException
  {
    rexec(localUsername, remoteUsername, terminalType, false);
  }

}