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 * @see org.apache.commons.net.SocketClient
062 * @see RExecClient
063 * @see RCommandClient
064 ***/
065
066 public class RLoginClient extends RCommandClient
067 {
068 /***
069 * The default rlogin port. Set to 513 in BSD Unix and according
070 * to RFC 1282.
071 ***/
072 public static final int DEFAULT_PORT = 513;
073
074 /***
075 * The default RLoginClient constructor. Initializes the
076 * default port to <code> DEFAULT_PORT </code>.
077 ***/
078 public RLoginClient()
079 {
080 setDefaultPort(DEFAULT_PORT);
081 }
082
083
084 /***
085 * Logins into a remote machine through the rlogind daemon on the server
086 * to which the RLoginClient is connected. After calling this method,
087 * you may interact with the remote login shell through its standard input
088 * and output streams. Standard error is sent over the same stream as
089 * standard output. You will typically be able to detect
090 * the termination of the remote login shell after reaching end of file
091 * on its standard output (accessible through
092 * {@link #getInputStream getInputStream() }. Disconnecting
093 * from the server or closing the process streams before reaching
094 * end of file will terminate the remote login shell in most cases.
095 * <p>
096 * If user authentication fails, the rlogind daemon will request that
097 * a password be entered interactively. You will be able to read the
098 * prompt from the output stream of the RLoginClient and write the
099 * password to the input stream of the RLoginClient.
100 * <p>
101 * @param localUsername The user account on the local machine that is
102 * trying to login to the remote host.
103 * @param remoteUsername The account name on the server that is
104 * being logged in to.
105 * @param terminalType The name of the user's terminal (e.g., "vt100",
106 * "network", etc.)
107 * @param terminalSpeed The speed of the user's terminal, expressed
108 * as a baud rate or bps (e.g., 9600 or 38400)
109 * @exception IOException If the rlogin() attempt fails. The exception
110 * will contain a message indicating the nature of the failure.
111 ***/
112 public void rlogin(String localUsername, String remoteUsername,
113 String terminalType, int terminalSpeed)
114 throws IOException
115 {
116 rexec(localUsername, remoteUsername, terminalType + "/" + terminalSpeed,
117 false);
118 }
119
120 /***
121 * Same as the other rlogin method, but no terminal speed is defined.
122 ***/
123 public void rlogin(String localUsername, String remoteUsername,
124 String terminalType)
125 throws IOException
126 {
127 rexec(localUsername, remoteUsername, terminalType, false);
128 }
129
130 }