001 /*
002 * Copyright 2001-2005 The Apache Software Foundation
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 * http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016 package org.apache.commons.net.bsd;
017
018 import java.io.IOException;
019
020 /***
021 * RLoginClient is very similar to
022 * {@link org.apache.commons.net.bsd.RCommandClient},
023 * from which it is derived, and uses the rcmd() facility implemented
024 * in RCommandClient to implement the functionality of the rlogin command that
025 * first appeared in 4.2BSD Unix. rlogin is a command used to login to
026 * a remote machine from a trusted host, sometimes without issuing a
027 * password. The trust relationship is the same as described in
028 * the documentation for
029 * {@link org.apache.commons.net.bsd.RCommandClient}.
030 * <p>
031 * As with virtually all of the client classes in org.apache.commons.net, this
032 * class derives from SocketClient. But it relies on the connection
033 * methods defined in RcommandClient which ensure that the local Socket
034 * will originate from an acceptable rshell port. The way to use
035 * RLoginClient is to first connect
036 * to the server, call the {@link #rlogin rlogin() } method,
037 * and then
038 * fetch the connection's input and output streams.
039 * Interaction with the remote command is controlled entirely through the
040 * I/O streams. Once you have finished processing the streams, you should
041 * invoke {@link org.apache.commons.net.bsd.RExecClient#disconnect disconnect() }
042 * to clean up properly.
043 * <p>
044 * The standard output and standard error streams of the
045 * remote process are transmitted over the same connection, readable
046 * from the input stream returned by
047 * {@link org.apache.commons.net.bsd.RExecClient#getInputStream getInputStream() }
048 * . Unlike RExecClient and RCommandClient, it is
049 * not possible to tell the rlogind daemon to return the standard error
050 * stream over a separate connection.
051 * {@link org.apache.commons.net.bsd.RExecClient#getErrorStream getErrorStream() }
052 * will always return null.
053 * The standard input of the remote process can be written to through
054 * the output stream returned by
055 * {@link org.apache.commons.net.bsd.RExecClient#getOutputStream getOutputSream() }
056 * .
057 * <p>
058 * <p>
059 * @author Daniel F. Savarese
060 * @see org.apache.commons.net.SocketClient
061 * @see RExecClient
062 * @see RCommandClient
063 ***/
064
065 public class RLoginClient extends RCommandClient
066 {
067 /***
068 * The default rlogin port. Set to 513 in BSD Unix and according
069 * to RFC 1282.
070 ***/
071 public static final int DEFAULT_PORT = 513;
072
073 /***
074 * The default RLoginClient constructor. Initializes the
075 * default port to <code> DEFAULT_PORT </code>.
076 ***/
077 public RLoginClient()
078 {
079 setDefaultPort(DEFAULT_PORT);
080 }
081
082
083 /***
084 * Logins into a remote machine through the rlogind daemon on the server
085 * to which the RLoginClient is connected. After calling this method,
086 * you may interact with the remote login shell through its standard input
087 * and output streams. Standard error is sent over the same stream as
088 * standard output. You will typically be able to detect
089 * the termination of the remote login shell after reaching end of file
090 * on its standard output (accessible through
091 * {@link #getInputStream getInputStream() }. Disconnecting
092 * from the server or closing the process streams before reaching
093 * end of file will terminate the remote login shell in most cases.
094 * <p>
095 * If user authentication fails, the rlogind daemon will request that
096 * a password be entered interactively. You will be able to read the
097 * prompt from the output stream of the RLoginClient and write the
098 * password to the input stream of the RLoginClient.
099 * <p>
100 * @param localUsername The user account on the local machine that is
101 * trying to login to the remote host.
102 * @param remoteUsername The account name on the server that is
103 * being logged in to.
104 * @param terminalType The name of the user's terminal (e.g., "vt100",
105 * "network", etc.)
106 * @param terminalSpeed The speed of the user's terminal, expressed
107 * as a baud rate or bps (e.g., 9600 or 38400)
108 * @exception IOException If the rlogin() attempt fails. The exception
109 * will contain a message indicating the nature of the failure.
110 ***/
111 public void rlogin(String localUsername, String remoteUsername,
112 String terminalType, int terminalSpeed)
113 throws IOException
114 {
115 rexec(localUsername, remoteUsername, terminalType + "/" + terminalSpeed,
116 false);
117 }
118
119 /***
120 * Same as the other rlogin method, but no terminal speed is defined.
121 ***/
122 public void rlogin(String localUsername, String remoteUsername,
123 String terminalType)
124 throws IOException
125 {
126 rexec(localUsername, remoteUsername, terminalType, false);
127 }
128
129 }