1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17
18 package org.apache.commons.net.bsd;
19
20 import java.io.IOException;
21
22 /***
23 * RLoginClient is very similar to
24 * {@link org.apache.commons.net.bsd.RCommandClient},
25 * from which it is derived, and uses the rcmd() facility implemented
26 * in RCommandClient to implement the functionality of the rlogin command that
27 * first appeared in 4.2BSD Unix. rlogin is a command used to login to
28 * a remote machine from a trusted host, sometimes without issuing a
29 * password. The trust relationship is the same as described in
30 * the documentation for
31 * {@link org.apache.commons.net.bsd.RCommandClient}.
32 * <p>
33 * As with virtually all of the client classes in org.apache.commons.net, this
34 * class derives from SocketClient. But it relies on the connection
35 * methods defined in RcommandClient which ensure that the local Socket
36 * will originate from an acceptable rshell port. The way to use
37 * RLoginClient is to first connect
38 * to the server, call the {@link #rlogin rlogin() } method,
39 * and then
40 * fetch the connection's input and output streams.
41 * Interaction with the remote command is controlled entirely through the
42 * I/O streams. Once you have finished processing the streams, you should
43 * invoke {@link org.apache.commons.net.bsd.RExecClient#disconnect disconnect() }
44 * to clean up properly.
45 * <p>
46 * The standard output and standard error streams of the
47 * remote process are transmitted over the same connection, readable
48 * from the input stream returned by
49 * {@link org.apache.commons.net.bsd.RExecClient#getInputStream getInputStream() }
50 * . Unlike RExecClient and RCommandClient, it is
51 * not possible to tell the rlogind daemon to return the standard error
52 * stream over a separate connection.
53 * {@link org.apache.commons.net.bsd.RExecClient#getErrorStream getErrorStream() }
54 * will always return null.
55 * The standard input of the remote process can be written to through
56 * the output stream returned by
57 * {@link org.apache.commons.net.bsd.RExecClient#getOutputStream getOutputSream() }
58 * .
59 * <p>
60 * <p>
61 * @author Daniel F. Savarese
62 * @see org.apache.commons.net.SocketClient
63 * @see RExecClient
64 * @see RCommandClient
65 ***/
66
67 public class RLoginClient extends RCommandClient
68 {
69 /***
70 * The default rlogin port. Set to 513 in BSD Unix and according
71 * to RFC 1282.
72 ***/
73 public static final int DEFAULT_PORT = 513;
74
75 /***
76 * The default RLoginClient constructor. Initializes the
77 * default port to <code> DEFAULT_PORT </code>.
78 ***/
79 public RLoginClient()
80 {
81 setDefaultPort(DEFAULT_PORT);
82 }
83
84
85 /***
86 * Logins into a remote machine through the rlogind daemon on the server
87 * to which the RLoginClient is connected. After calling this method,
88 * you may interact with the remote login shell through its standard input
89 * and output streams. Standard error is sent over the same stream as
90 * standard output. You will typically be able to detect
91 * the termination of the remote login shell after reaching end of file
92 * on its standard output (accessible through
93 * {@link #getInputStream getInputStream() }. Disconnecting
94 * from the server or closing the process streams before reaching
95 * end of file will terminate the remote login shell in most cases.
96 * <p>
97 * If user authentication fails, the rlogind daemon will request that
98 * a password be entered interactively. You will be able to read the
99 * 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 }