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Diffstat (limited to 'org/apache/commons/net/bsd/RExecClient.java')
| -rw-r--r-- | org/apache/commons/net/bsd/RExecClient.java | 292 |
1 files changed, 0 insertions, 292 deletions
diff --git a/org/apache/commons/net/bsd/RExecClient.java b/org/apache/commons/net/bsd/RExecClient.java deleted file mode 100644 index 2924120..0000000 --- a/org/apache/commons/net/bsd/RExecClient.java +++ /dev/null @@ -1,292 +0,0 @@ -/*
- * Licensed to the Apache Software Foundation (ASF) under one or more
- * contributor license agreements. See the NOTICE file distributed with
- * this work for additional information regarding copyright ownership.
- * The ASF licenses this file to You under the Apache License, Version 2.0
- * (the "License"); you may not use this file except in compliance with
- * the License. You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package org.apache.commons.net.bsd;
-
-import java.io.IOException;
-import java.io.InputStream;
-import java.io.OutputStream;
-import java.net.ServerSocket;
-import java.net.Socket;
-
-import org.apache.commons.net.SocketClient;
-import org.apache.commons.net.io.SocketInputStream;
-
-/***
- * RExecClient implements the rexec() facility that first appeared in
- * 4.2BSD Unix. This class will probably only be of use for connecting
- * to Unix systems and only when the rexecd daemon is configured to run,
- * which is a rarity these days because of the security risks involved.
- * However, rexec() can be very useful for performing administrative tasks
- * on a network behind a firewall.
- * <p>
- * As with virtually all of the client classes in org.apache.commons.net, this
- * class derives from SocketClient, inheriting its connection methods.
- * The way to use RExecClient is to first connect
- * to the server, call the {@link #rexec rexec() } method, and then
- * fetch the connection's input, output, and optionally error streams.
- * Interaction with the remote command is controlled entirely through the
- * I/O streams. Once you have finished processing the streams, you should
- * invoke {@link #disconnect disconnect() } to clean up properly.
- * <p>
- * By default the standard output and standard error streams of the
- * remote process are transmitted over the same connection, readable
- * from the input stream returned by
- * {@link #getInputStream getInputStream() }. However, it is
- * possible to tell the rexecd daemon to return the standard error
- * stream over a separate connection, readable from the input stream
- * returned by {@link #getErrorStream getErrorStream() }. You
- * can specify that a separate connection should be created for standard
- * error by setting the boolean <code> separateErrorStream </code>
- * parameter of {@link #rexec rexec() } to <code> true </code>.
- * The standard input of the remote process can be written to through
- * the output stream returned by
- * {@link #getOutputStream getOutputSream() }.
- * <p>
- * <p>
- * @author Daniel F. Savarese
- * @see SocketClient
- * @see RCommandClient
- * @see RLoginClient
- ***/
-
-public class RExecClient extends SocketClient
-{
- /***
- * The default rexec port. Set to 512 in BSD Unix.
- ***/
- public static final int DEFAULT_PORT = 512;
-
- private boolean __remoteVerificationEnabled;
-
- /***
- * If a separate error stream is requested, <code>_errorStream_</code>
- * will point to an InputStream from which the standard error of the
- * remote process can be read (after a call to rexec()). Otherwise,
- * <code> _errorStream_ </code> will be null.
- ***/
- protected InputStream _errorStream_;
-
- // This can be overridden in local package to implement port range
- // limitations of rcmd and rlogin
- InputStream _createErrorStream() throws IOException
- {
- ServerSocket server;
- Socket socket;
-
- server = _serverSocketFactory_.createServerSocket(0, 1, getLocalAddress());
-
- _output_.write(Integer.toString(server.getLocalPort()).getBytes());
- _output_.write('\0');
- _output_.flush();
-
- socket = server.accept();
- server.close();
-
- if (__remoteVerificationEnabled && !verifyRemote(socket))
- {
- socket.close();
- throw new IOException(
- "Security violation: unexpected connection attempt by " +
- socket.getInetAddress().getHostAddress());
- }
-
- return (new SocketInputStream(socket, socket.getInputStream()));
- }
-
-
- /***
- * The default RExecClient constructor. Initializes the
- * default port to <code> DEFAULT_PORT </code>.
- ***/
- public RExecClient()
- {
- _errorStream_ = null;
- setDefaultPort(DEFAULT_PORT);
- }
-
-
- /***
- * Returns the InputStream from which the standard outputof the remote
- * process can be read. The input stream will only be set after a
- * successful rexec() invocation.
- * <p>
- * @return The InputStream from which the standard output of the remote
- * process can be read.
- ***/
- public InputStream getInputStream()
- {
- return _input_;
- }
-
-
- /***
- * Returns the OutputStream through which the standard input of the remote
- * process can be written. The output stream will only be set after a
- * successful rexec() invocation.
- * <p>
- * @return The OutputStream through which the standard input of the remote
- * process can be written.
- ***/
- public OutputStream getOutputStream()
- {
- return _output_;
- }
-
-
- /***
- * Returns the InputStream from which the standard error of the remote
- * process can be read if a separate error stream is requested from
- * the server. Otherwise, null will be returned. The error stream
- * will only be set after a successful rexec() invocation.
- * <p>
- * @return The InputStream from which the standard error of the remote
- * process can be read if a separate error stream is requested from
- * the server. Otherwise, null will be returned.
- ***/
- public InputStream getErrorStream()
- {
- return _errorStream_;
- }
-
-
- /***
- * Remotely executes a command through the rexecd daemon on the server
- * to which the RExecClient is connected. After calling this method,
- * you may interact with the remote process through its standard input,
- * output, and error streams. You will typically be able to detect
- * the termination of the remote process after reaching end of file
- * on its standard output (accessible through
- * {@link #getInputStream getInputStream() }. Disconnecting
- * from the server or closing the process streams before reaching
- * end of file will not necessarily terminate the remote process.
- * <p>
- * If a separate error stream is requested, the remote server will
- * connect to a local socket opened by RExecClient, providing an
- * independent stream through which standard error will be transmitted.
- * RExecClient will do a simple security check when it accepts a
- * connection for this error stream. If the connection does not originate
- * from the remote server, an IOException will be thrown. This serves as
- * a simple protection against possible hijacking of the error stream by
- * an attacker monitoring the rexec() negotiation. You may disable this
- * behavior with {@link #setRemoteVerificationEnabled setRemoteVerificationEnabled()}
- * .
- * <p>
- * @param username The account name on the server through which to execute
- * the command.
- * @param password The plain text password of the user account.
- * @param command The command, including any arguments, to execute.
- * @param separateErrorStream True if you would like the standard error
- * to be transmitted through a different stream than standard output.
- * False if not.
- * @exception IOException If the rexec() attempt fails. The exception
- * will contain a message indicating the nature of the failure.
- ***/
- public void rexec(String username, String password,
- String command, boolean separateErrorStream)
- throws IOException
- {
- int ch;
-
- if (separateErrorStream)
- {
- _errorStream_ = _createErrorStream();
- }
- else
- {
- _output_.write('\0');
- }
-
- _output_.write(username.getBytes());
- _output_.write('\0');
- _output_.write(password.getBytes());
- _output_.write('\0');
- _output_.write(command.getBytes());
- _output_.write('\0');
- _output_.flush();
-
- ch = _input_.read();
- if (ch > 0)
- {
- StringBuffer buffer = new StringBuffer();
-
- while ((ch = _input_.read()) != -1 && ch != '\n')
- buffer.append((char)ch);
-
- throw new IOException(buffer.toString());
- }
- else if (ch < 0)
- {
- throw new IOException("Server closed connection.");
- }
- }
-
-
- /***
- * Same as <code> rexec(username, password, command, false); </code>
- ***/
- public void rexec(String username, String password,
- String command)
- throws IOException
- {
- rexec(username, password, command, false);
- }
-
- /***
- * Disconnects from the server, closing all associated open sockets and
- * streams.
- * <p>
- * @exception IOException If there an error occurs while disconnecting.
- ***/
- @Override
- public void disconnect() throws IOException
- {
- if (_errorStream_ != null)
- _errorStream_.close();
- _errorStream_ = null;
- super.disconnect();
- }
-
-
- /***
- * Enable or disable verification that the remote host connecting to
- * create a separate error stream is the same as the host to which
- * the standard out stream is connected. The default is for verification
- * to be enabled. You may set this value at any time, whether the
- * client is currently connected or not.
- * <p>
- * @param enable True to enable verification, false to disable verification.
- ***/
- public final void setRemoteVerificationEnabled(boolean enable)
- {
- __remoteVerificationEnabled = enable;
- }
-
- /***
- * Return whether or not verification of the remote host providing a
- * separate error stream is enabled. The default behavior is for
- * verification to be enabled.
- * <p>
- * @return True if verification is enabled, false if not.
- ***/
- public final boolean isRemoteVerificationEnabled()
- {
- return __remoteVerificationEnabled;
- }
-
-}
-
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