org.apache.commons.net.tftp.TFTPClient Maven / Gradle / Ivy
/*
* 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.tftp;
import java.io.IOException;
import java.io.InputStream;
import java.io.InterruptedIOException;
import java.io.OutputStream;
import java.net.InetAddress;
import java.net.SocketException;
import java.net.UnknownHostException;
import org.apache.commons.net.io.FromNetASCIIOutputStream;
import org.apache.commons.net.io.ToNetASCIIInputStream;
/**
* The TFTPClient class encapsulates all the aspects of the TFTP protocol
* necessary to receive and send files through TFTP. It is derived from
* the {@link org.apache.commons.net.tftp.TFTP} because
* it is more convenient than using aggregation, and as a result exposes
* the same set of methods to allow you to deal with the TFTP protocol
* directly. However, almost every user should only be concerend with the
* the {@link org.apache.commons.net.DatagramSocketClient#open open() },
* {@link org.apache.commons.net.DatagramSocketClient#close close() },
* {@link #sendFile sendFile() }, and
* {@link #receiveFile receiveFile() } methods. Additionally, the
* {@link #setMaxTimeouts setMaxTimeouts() } and
* {@link org.apache.commons.net.DatagramSocketClient#setDefaultTimeout setDefaultTimeout() }
* methods may be of importance for performance
* tuning.
*
* Details regarding the TFTP protocol and the format of TFTP packets can
* be found in RFC 783. But the point of these classes is to keep you
* from having to worry about the internals.
*
*
* @see TFTP
* @see TFTPPacket
* @see TFTPPacketException
*/
public class TFTPClient extends TFTP
{
/**
* The default number of times a receive attempt is allowed to timeout
* before ending attempts to retry the receive and failing. The default
* is 5 timeouts.
*/
public static final int DEFAULT_MAX_TIMEOUTS = 5;
/** The maximum number of timeouts allowed before failing. */
private int maxTimeouts;
/** The number of bytes received in the ongoing download. */
private long totalBytesReceived;
/** The number of bytes sent in the ongoing upload. */
private long totalBytesSent;
/**
* Creates a TFTPClient instance with a default timeout of DEFAULT_TIMEOUT,
* maximum timeouts value of DEFAULT_MAX_TIMEOUTS, a null socket,
* and buffered operations disabled.
*/
public TFTPClient()
{
maxTimeouts = DEFAULT_MAX_TIMEOUTS;
}
/**
* Sets the maximum number of times a receive attempt is allowed to
* timeout during a receiveFile() or sendFile() operation before ending
* attempts to retry the receive and failing.
* The default is DEFAULT_MAX_TIMEOUTS.
*
* @param numTimeouts The maximum number of timeouts to allow. Values
* less than 1 should not be used, but if they are, they are
* treated as 1.
*/
public void setMaxTimeouts(final int numTimeouts)
{
if (numTimeouts < 1) {
maxTimeouts = 1;
} else {
maxTimeouts = numTimeouts;
}
}
/**
* Returns the maximum number of times a receive attempt is allowed to
* timeout before ending attempts to retry the receive and failing.
*
* @return The maximum number of timeouts allowed.
*/
public int getMaxTimeouts()
{
return maxTimeouts;
}
/**
* @return The number of bytes received in the ongoing download
*/
public long getTotalBytesReceived() {
return totalBytesReceived;
}
/**
* @return The number of bytes sent in the ongoing download
*/
public long getTotalBytesSent() {
return totalBytesSent;
}
/**
* Requests a named file from a remote host, writes the
* file to an OutputStream, closes the connection, and returns the number
* of bytes read. A local UDP socket must first be created by
* {@link org.apache.commons.net.DatagramSocketClient#open open()} before
* invoking this method. This method will not close the OutputStream
* containing the file; you must close it after the method invocation.
*
* @param fileName The name of the file to receive.
* @param mode The TFTP mode of the transfer (one of the MODE constants).
* @param output The OutputStream to which the file should be written.
* @param host The remote host serving the file.
* @param port The port number of the remote TFTP server.
* @return number of bytes read
* @throws IOException If an I/O error occurs. The nature of the
* error will be reported in the message.
*/
public int receiveFile(final String fileName, final int mode, OutputStream output,
InetAddress host, final int port) throws IOException
{
int bytesRead = 0;
int lastBlock = 0;
int block = 1;
int hostPort = 0;
int dataLength = 0;
totalBytesReceived = 0;
if (mode == TFTP.ASCII_MODE) {
output = new FromNetASCIIOutputStream(output);
}
TFTPPacket sent = new TFTPReadRequestPacket(host, port, fileName, mode);
final TFTPAckPacket ack = new TFTPAckPacket(host, port, 0);
beginBufferedOps();
boolean justStarted = true;
try {
do { // while more data to fetch
bufferedSend(sent); // start the fetch/send an ack
boolean wantReply = true;
int timeouts = 0;
do { // until successful response
try {
final TFTPPacket received = bufferedReceive();
// The first time we receive we get the port number and
// answering host address (for hosts with multiple IPs)
final int recdPort = received.getPort();
final InetAddress recdAddress = received.getAddress();
if (justStarted) {
justStarted = false;
if (recdPort == port) { // must not use the control port here
final TFTPErrorPacket error = new TFTPErrorPacket(recdAddress,
recdPort, TFTPErrorPacket.UNKNOWN_TID,
"INCORRECT SOURCE PORT");
bufferedSend(error);
throw new IOException("Incorrect source port ("+recdPort+") in request reply.");
}
hostPort = recdPort;
ack.setPort(hostPort);
if(!host.equals(recdAddress))
{
host = recdAddress;
ack.setAddress(host);
sent.setAddress(host);
}
}
// Comply with RFC 783 indication that an error acknowledgment
// should be sent to originator if unexpected TID or host.
if (host.equals(recdAddress) && recdPort == hostPort) {
switch (received.getType()) {
case TFTPPacket.ERROR:
TFTPErrorPacket error = (TFTPErrorPacket)received;
throw new IOException("Error code " + error.getError() +
" received: " + error.getMessage());
case TFTPPacket.DATA:
final TFTPDataPacket data = (TFTPDataPacket)received;
dataLength = data.getDataLength();
lastBlock = data.getBlockNumber();
if (lastBlock == block) { // is the next block number?
try {
output.write(data.getData(), data.getDataOffset(), dataLength);
} catch (final IOException e) {
error = new TFTPErrorPacket(host, hostPort,
TFTPErrorPacket.OUT_OF_SPACE,
"File write failed.");
bufferedSend(error);
throw e;
}
++block;
if (block > 65535) {
// wrap the block number
block = 0;
}
wantReply = false; // got the next block, drop out to ack it
} else { // unexpected block number
discardPackets();
if (lastBlock == (block == 0 ? 65535 : block - 1)) {
wantReply = false; // Resend last acknowledgemen
}
}
break;
default:
throw new IOException("Received unexpected packet type (" + received.getType() + ")");
}
} else { // incorrect host or TID
final TFTPErrorPacket error = new TFTPErrorPacket(recdAddress, recdPort,
TFTPErrorPacket.UNKNOWN_TID,
"Unexpected host or port.");
bufferedSend(error);
}
} catch (final SocketException | InterruptedIOException e) {
if (++timeouts >= maxTimeouts) {
throw new IOException("Connection timed out.");
}
} catch (final TFTPPacketException e) {
throw new IOException("Bad packet: " + e.getMessage());
}
} while(wantReply); // waiting for response
ack.setBlockNumber(lastBlock);
sent = ack;
bytesRead += dataLength;
totalBytesReceived += dataLength;
} while (dataLength == TFTPPacket.SEGMENT_SIZE); // not eof
bufferedSend(sent); // send the final ack
} finally {
endBufferedOps();
}
return bytesRead;
}
/**
* Requests a named file from a remote host, writes the
* file to an OutputStream, closes the connection, and returns the number
* of bytes read. A local UDP socket must first be created by
* {@link org.apache.commons.net.DatagramSocketClient#open open()} before
* invoking this method. This method will not close the OutputStream
* containing the file; you must close it after the method invocation.
*
* @param fileName The name of the file to receive.
* @param mode The TFTP mode of the transfer (one of the MODE constants).
* @param output The OutputStream to which the file should be written.
* @param hostname The name of the remote host serving the file.
* @param port The port number of the remote TFTP server.
* @return number of bytes read
* @throws IOException If an I/O error occurs. The nature of the
* error will be reported in the message.
* @throws UnknownHostException If the hostname cannot be resolved.
*/
public int receiveFile(final String fileName, final int mode, final OutputStream output,
final String hostname, final int port)
throws UnknownHostException, IOException
{
return receiveFile(fileName, mode, output, InetAddress.getByName(hostname),
port);
}
/**
* Same as calling receiveFile(fileName, mode, output, host, TFTP.DEFAULT_PORT).
*
* @param fileName The name of the file to receive.
* @param mode The TFTP mode of the transfer (one of the MODE constants).
* @param output The OutputStream to which the file should be written.
* @param host The remote host serving the file.
* @return number of bytes read
* @throws IOException If an I/O error occurs. The nature of the
* error will be reported in the message.
*/
public int receiveFile(final String fileName, final int mode, final OutputStream output,
final InetAddress host)
throws IOException
{
return receiveFile(fileName, mode, output, host, DEFAULT_PORT);
}
/**
* Same as calling receiveFile(fileName, mode, output, hostname, TFTP.DEFAULT_PORT).
*
* @param fileName The name of the file to receive.
* @param mode The TFTP mode of the transfer (one of the MODE constants).
* @param output The OutputStream to which the file should be written.
* @param hostname The name of the remote host serving the file.
* @return number of bytes read
* @throws IOException If an I/O error occurs. The nature of the
* error will be reported in the message.
* @throws UnknownHostException If the hostname cannot be resolved.
*/
public int receiveFile(final String fileName, final int mode, final OutputStream output,
final String hostname)
throws UnknownHostException, IOException
{
return receiveFile(fileName, mode, output, InetAddress.getByName(hostname),
DEFAULT_PORT);
}
/**
* Requests to send a file to a remote host, reads the file from an
* InputStream, sends the file to the remote host, and closes the
* connection. A local UDP socket must first be created by
* {@link org.apache.commons.net.DatagramSocketClient#open open()} before
* invoking this method. This method will not close the InputStream
* containing the file; you must close it after the method invocation.
*
* @param fileName The name the remote server should use when creating
* the file on its file system.
* @param mode The TFTP mode of the transfer (one of the MODE constants).
* @param input the input stream containing the data to be sent
* @param host The remote host receiving the file.
* @param port The port number of the remote TFTP server.
* @throws IOException If an I/O error occurs. The nature of the
* error will be reported in the message.
*/
public void sendFile(final String fileName, final int mode, InputStream input,
InetAddress host, final int port) throws IOException
{
int block = 0;
int hostPort = 0;
boolean justStarted = true;
boolean lastAckWait = false;
totalBytesSent = 0L;
if (mode == TFTP.ASCII_MODE) {
input = new ToNetASCIIInputStream(input);
}
TFTPPacket sent = new TFTPWriteRequestPacket(host, port, fileName, mode);
final TFTPDataPacket data = new TFTPDataPacket(host, port, 0, sendBuffer, 4, 0);
beginBufferedOps();
try {
do { // until eof
// first time: block is 0, lastBlock is 0, send a request packet.
// subsequent: block is integer starting at 1, send data packet.
bufferedSend(sent);
boolean wantReply = true;
int timeouts = 0;
do {
try {
final TFTPPacket received = bufferedReceive();
final InetAddress recdAddress = received.getAddress();
final int recdPort = received.getPort();
// The first time we receive we get the port number and
// answering host address (for hosts with multiple IPs)
if (justStarted) {
justStarted = false;
if (recdPort == port) { // must not use the control port here
final TFTPErrorPacket error = new TFTPErrorPacket(recdAddress,
recdPort, TFTPErrorPacket.UNKNOWN_TID,
"INCORRECT SOURCE PORT");
bufferedSend(error);
throw new IOException("Incorrect source port ("+recdPort+") in request reply.");
}
hostPort = recdPort;
data.setPort(hostPort);
if (!host.equals(recdAddress)) {
host = recdAddress;
data.setAddress(host);
sent.setAddress(host);
}
}
// Comply with RFC 783 indication that an error acknowledgment
// should be sent to originator if unexpected TID or host.
if (host.equals(recdAddress) && recdPort == hostPort) {
switch (received.getType()) {
case TFTPPacket.ERROR:
final TFTPErrorPacket error = (TFTPErrorPacket)received;
throw new IOException("Error code " + error.getError() +
" received: " + error.getMessage());
case TFTPPacket.ACKNOWLEDGEMENT:
final int lastBlock = ((TFTPAckPacket)received).getBlockNumber();
if (lastBlock == block) {
++block;
if (block > 65535) {
// wrap the block number
block = 0;
}
wantReply = false; // got the ack we want
} else {
discardPackets();
}
break;
default:
throw new IOException("Received unexpected packet type.");
}
} else { // wrong host or TID; send error
final TFTPErrorPacket error = new TFTPErrorPacket(recdAddress,
recdPort,
TFTPErrorPacket.UNKNOWN_TID,
"Unexpected host or port.");
bufferedSend(error);
}
} catch (final SocketException | InterruptedIOException e) {
if (++timeouts >= maxTimeouts) {
throw new IOException("Connection timed out.");
}
} catch (final TFTPPacketException e) {
throw new IOException("Bad packet: " + e.getMessage());
}
// retry until a good ack
} while(wantReply);
if (lastAckWait) {
break; // we were waiting for this; now all done
}
int dataLength = TFTPPacket.SEGMENT_SIZE;
int offset = 4;
int totalThisPacket = 0;
int bytesRead = 0;
while (dataLength > 0 &&
(bytesRead = input.read(sendBuffer, offset, dataLength)) > 0) {
offset += bytesRead;
dataLength -= bytesRead;
totalThisPacket += bytesRead;
}
if( totalThisPacket < TFTPPacket.SEGMENT_SIZE ) {
/* this will be our last packet -- send, wait for ack, stop */
lastAckWait = true;
}
data.setBlockNumber(block);
data.setData(sendBuffer, 4, totalThisPacket);
sent = data;
totalBytesSent += totalThisPacket;
} while (true); // loops until after lastAckWait is set
} finally {
endBufferedOps();
}
}
/**
* Requests to send a file to a remote host, reads the file from an
* InputStream, sends the file to the remote host, and closes the
* connection. A local UDP socket must first be created by
* {@link org.apache.commons.net.DatagramSocketClient#open open()} before
* invoking this method. This method will not close the InputStream
* containing the file; you must close it after the method invocation.
*
* @param fileName The name the remote server should use when creating
* the file on its file system.
* @param mode The TFTP mode of the transfer (one of the MODE constants).
* @param input the input stream containing the data to be sent
* @param hostname The name of the remote host receiving the file.
* @param port The port number of the remote TFTP server.
* @throws IOException If an I/O error occurs. The nature of the
* error will be reported in the message.
* @throws UnknownHostException If the hostname cannot be resolved.
*/
public void sendFile(final String fileName, final int mode, final InputStream input,
final String hostname, final int port)
throws UnknownHostException, IOException
{
sendFile(fileName, mode, input, InetAddress.getByName(hostname), port);
}
/**
* Same as calling sendFile(fileName, mode, input, host, TFTP.DEFAULT_PORT).
*
* @param fileName The name the remote server should use when creating
* the file on its file system.
* @param mode The TFTP mode of the transfer (one of the MODE constants).
* @param input the input stream containing the data to be sent
* @param host The name of the remote host receiving the file.
* @throws IOException If an I/O error occurs. The nature of the
* error will be reported in the message.
* @throws UnknownHostException If the hostname cannot be resolved.
*/
public void sendFile(final String fileName, final int mode, final InputStream input,
final InetAddress host)
throws IOException
{
sendFile(fileName, mode, input, host, DEFAULT_PORT);
}
/**
* Same as calling sendFile(fileName, mode, input, hostname, TFTP.DEFAULT_PORT).
*
* @param fileName The name the remote server should use when creating
* the file on its file system.
* @param mode The TFTP mode of the transfer (one of the MODE constants).
* @param input the input stream containing the data to be sent
* @param hostname The name of the remote host receiving the file.
* @throws IOException If an I/O error occurs. The nature of the
* error will be reported in the message.
* @throws UnknownHostException If the hostname cannot be resolved.
*/
public void sendFile(final String fileName, final int mode, final InputStream input,
final String hostname)
throws UnknownHostException, IOException
{
sendFile(fileName, mode, input, InetAddress.getByName(hostname),
DEFAULT_PORT);
}
}