001 /*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements. See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License. You may obtain a copy of the License at
008 *
009 * http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017
018 package org.apache.commons.net.bsd;
019
020 import java.io.IOException;
021
022 /***
023 * RLoginClient is very similar to
024 * {@link org.apache.commons.net.bsd.RCommandClient},
025 * from which it is derived, and uses the rcmd() facility implemented
026 * in RCommandClient to implement the functionality of the rlogin command that
027 * first appeared in 4.2BSD Unix. rlogin is a command used to login to
028 * a remote machine from a trusted host, sometimes without issuing a
029 * password. The trust relationship is the same as described in
030 * the documentation for
031 * {@link org.apache.commons.net.bsd.RCommandClient}.
032 * <p>
033 * As with virtually all of the client classes in org.apache.commons.net, this
034 * class derives from SocketClient. But it relies on the connection
035 * methods defined in RcommandClient which ensure that the local Socket
036 * will originate from an acceptable rshell port. The way to use
037 * RLoginClient is to first connect
038 * to the server, call the {@link #rlogin rlogin() } method,
039 * and then
040 * fetch the connection's input and output streams.
041 * Interaction with the remote command is controlled entirely through the
042 * I/O streams. Once you have finished processing the streams, you should
043 * invoke {@link org.apache.commons.net.bsd.RExecClient#disconnect disconnect() }
044 * to clean up properly.
045 * <p>
046 * The standard output and standard error streams of the
047 * remote process are transmitted over the same connection, readable
048 * from the input stream returned by
049 * {@link org.apache.commons.net.bsd.RExecClient#getInputStream getInputStream() }
050 * . Unlike RExecClient and RCommandClient, it is
051 * not possible to tell the rlogind daemon to return the standard error
052 * stream over a separate connection.
053 * {@link org.apache.commons.net.bsd.RExecClient#getErrorStream getErrorStream() }
054 * will always return null.
055 * The standard input of the remote process can be written to through
056 * the output stream returned by
057 * {@link org.apache.commons.net.bsd.RExecClient#getOutputStream getOutputSream() }
058 * .
059 * <p>
060 * <p>
061 * @author Daniel F. Savarese
062 * @see org.apache.commons.net.SocketClient
063 * @see RExecClient
064 * @see RCommandClient
065 ***/
066
067 public class RLoginClient extends RCommandClient
068 {
069 /***
070 * The default rlogin port. Set to 513 in BSD Unix and according
071 * to RFC 1282.
072 ***/
073 public static final int DEFAULT_PORT = 513;
074
075 /***
076 * The default RLoginClient constructor. Initializes the
077 * default port to <code> DEFAULT_PORT </code>.
078 ***/
079 public RLoginClient()
080 {
081 setDefaultPort(DEFAULT_PORT);
082 }
083
084
085 /***
086 * Logins into a remote machine through the rlogind daemon on the server
087 * to which the RLoginClient is connected. After calling this method,
088 * you may interact with the remote login shell through its standard input
089 * and output streams. Standard error is sent over the same stream as
090 * standard output. You will typically be able to detect
091 * the termination of the remote login shell after reaching end of file
092 * on its standard output (accessible through
093 * {@link #getInputStream getInputStream() }. Disconnecting
094 * from the server or closing the process streams before reaching
095 * end of file will terminate the remote login shell in most cases.
096 * <p>
097 * If user authentication fails, the rlogind daemon will request that
098 * a password be entered interactively. You will be able to read the
099 * prompt from the output stream of the RLoginClient and write the
100 * password to the input stream of the RLoginClient.
101 * <p>
102 * @param localUsername The user account on the local machine that is
103 * trying to login to the remote host.
104 * @param remoteUsername The account name on the server that is
105 * being logged in to.
106 * @param terminalType The name of the user's terminal (e.g., "vt100",
107 * "network", etc.)
108 * @param terminalSpeed The speed of the user's terminal, expressed
109 * as a baud rate or bps (e.g., 9600 or 38400)
110 * @exception IOException If the rlogin() attempt fails. The exception
111 * will contain a message indicating the nature of the failure.
112 ***/
113 public void rlogin(String localUsername, String remoteUsername,
114 String terminalType, int terminalSpeed)
115 throws IOException
116 {
117 rexec(localUsername, remoteUsername, terminalType + "/" + terminalSpeed,
118 false);
119 }
120
121 /***
122 * Same as the other rlogin method, but no terminal speed is defined.
123 ***/
124 public void rlogin(String localUsername, String remoteUsername,
125 String terminalType)
126 throws IOException
127 {
128 rexec(localUsername, remoteUsername, terminalType, false);
129 }
130
131 }