From 063284837c8c366e5502b1b0264b8eb807b61732 Mon Sep 17 00:00:00 2001 From: Joe Robinson Date: Wed, 27 Oct 2010 14:21:09 +0100 Subject: Basic upload functionality to predifined location, with basic file browser --- org/apache/commons/net/tftp/TFTPPacket.java | 247 ++++++++++++++++++++++++++++ 1 file changed, 247 insertions(+) create mode 100644 org/apache/commons/net/tftp/TFTPPacket.java (limited to 'org/apache/commons/net/tftp/TFTPPacket.java') diff --git a/org/apache/commons/net/tftp/TFTPPacket.java b/org/apache/commons/net/tftp/TFTPPacket.java new file mode 100644 index 0000000..e1dc5f1 --- /dev/null +++ b/org/apache/commons/net/tftp/TFTPPacket.java @@ -0,0 +1,247 @@ +/* + * 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.net.DatagramPacket; +import java.net.InetAddress; + +/*** + * TFTPPacket is an abstract class encapsulating the functionality common + * to the 5 types of TFTP packets. It also provides a static factory + * method that will create the correct TFTP packet instance from a + * datagram. This relieves the programmer from having to figure out what + * kind of TFTP packet is contained in a datagram and create it himself. + *

+ * 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. Additionally, only very + * few people should have to care about any of the TFTPPacket classes + * or derived classes. Almost all users should only be concerned with the + * {@link org.apache.commons.net.tftp.TFTPClient} class + * {@link org.apache.commons.net.tftp.TFTPClient#receiveFile receiveFile()} + * and + * {@link org.apache.commons.net.tftp.TFTPClient#sendFile sendFile()} + * methods. + *

+ *

+ * @author Daniel F. Savarese + * @see TFTPPacketException + * @see TFTP + ***/ + +public abstract class TFTPPacket +{ + /*** + * The minimum size of a packet. This is 4 bytes. It is enough + * to store the opcode and blocknumber or other required data + * depending on the packet type. + ***/ + static final int MIN_PACKET_SIZE = 4; + + /*** + * This is the actual TFTP spec + * identifier and is equal to 1. + * Identifier returned by {@link #getType getType()} + * indicating a read request packet. + ***/ + public static final int READ_REQUEST = 1; + + /*** + * This is the actual TFTP spec + * identifier and is equal to 2. + * Identifier returned by {@link #getType getType()} + * indicating a write request packet. + ***/ + public static final int WRITE_REQUEST = 2; + + /*** + * This is the actual TFTP spec + * identifier and is equal to 3. + * Identifier returned by {@link #getType getType()} + * indicating a data packet. + ***/ + public static final int DATA = 3; + + /*** + * This is the actual TFTP spec + * identifier and is equal to 4. + * Identifier returned by {@link #getType getType()} + * indicating an acknowledgement packet. + ***/ + public static final int ACKNOWLEDGEMENT = 4; + + /*** + * This is the actual TFTP spec + * identifier and is equal to 5. + * Identifier returned by {@link #getType getType()} + * indicating an error packet. + ***/ + public static final int ERROR = 5; + + /*** + * The TFTP data packet maximum segment size in bytes. This is 512 + * and is useful for those familiar with the TFTP protocol who want + * to use the {@link org.apache.commons.net.tftp.TFTP} + * class methods to implement their own TFTP servers or clients. + ***/ + public static final int SEGMENT_SIZE = 512; + + /*** The type of packet. ***/ + int _type; + + /*** The port the packet came from or is going to. ***/ + int _port; + + /*** The host the packet is going to be sent or where it came from. ***/ + InetAddress _address; + + /*** + * When you receive a datagram that you expect to be a TFTP packet, you use + * this factory method to create the proper TFTPPacket object + * encapsulating the data contained in that datagram. This method is the + * only way you can instantiate a TFTPPacket derived class from a + * datagram. + *

+ * @param datagram The datagram containing a TFTP packet. + * @return The TFTPPacket object corresponding to the datagram. + * @exception TFTPPacketException If the datagram does not contain a valid + * TFTP packet. + ***/ + public final static TFTPPacket newTFTPPacket(DatagramPacket datagram) + throws TFTPPacketException + { + byte[] data; + TFTPPacket packet = null; + + if (datagram.getLength() < MIN_PACKET_SIZE) + throw new TFTPPacketException( + "Bad packet. Datagram data length is too short."); + + data = datagram.getData(); + + switch (data[1]) + { + case READ_REQUEST: + packet = new TFTPReadRequestPacket(datagram); + break; + case WRITE_REQUEST: + packet = new TFTPWriteRequestPacket(datagram); + break; + case DATA: + packet = new TFTPDataPacket(datagram); + break; + case ACKNOWLEDGEMENT: + packet = new TFTPAckPacket(datagram); + break; + case ERROR: + packet = new TFTPErrorPacket(datagram); + break; + default: + throw new TFTPPacketException( + "Bad packet. Invalid TFTP operator code."); + } + + return packet; + } + + /*** + * This constructor is not visible outside of the package. It is used + * by subclasses within the package to initialize base data. + *

+ * @param type The type of the packet. + * @param address The host the packet came from or is going to be sent. + * @param port The port the packet came from or is going to be sent. + **/ + TFTPPacket(int type, InetAddress address, int port) + { + _type = type; + _address = address; + _port = port; + } + + /*** + * This is an abstract method only available within the package for + * implementing efficient datagram transport by elminating buffering. + * It takes a datagram as an argument, and a byte buffer in which + * to store the raw datagram data. Inside the method, the data + * should be set as the datagram's data and the datagram returned. + *

+ * @param datagram The datagram to create. + * @param data The buffer to store the packet and to use in the datagram. + * @return The datagram argument. + ***/ + abstract DatagramPacket _newDatagram(DatagramPacket datagram, byte[] data); + + /*** + * Creates a UDP datagram containing all the TFTP packet + * data in the proper format. + * This is an abstract method, exposed to the programmer in case he + * wants to implement his own TFTP client instead of using + * the {@link org.apache.commons.net.tftp.TFTPClient} + * class. + * Under normal circumstances, you should not have a need to call this + * method. + *

+ * @return A UDP datagram containing the TFTP packet. + ***/ + public abstract DatagramPacket newDatagram(); + + /*** + * Returns the type of the packet. + *

+ * @return The type of the packet. + ***/ + public final int getType() + { + return _type; + } + + /*** + * Returns the address of the host where the packet is going to be sent + * or where it came from. + *

+ * @return The type of the packet. + ***/ + public final InetAddress getAddress() + { + return _address; + } + + /*** + * Returns the port where the packet is going to be sent + * or where it came from. + *

+ * @return The port where the packet came from or where it is going. + ***/ + public final int getPort() + { + return _port; + } + + /*** Sets the port where the packet is going to be sent. ***/ + public final void setPort(int port) + { + _port = port; + } + + /*** Sets the host address where the packet is going to be sent. ***/ + public final void setAddress(InetAddress address) + { + _address = address; + } +} -- cgit v1.2.3