Files
libremetaverse/Programs/mapgenerator/template.cs
John Hurliman 2e4aa31e4a * Remove an unused BuildPacket function in _Packets_.cs
* Make all blocks inherit from the abstract base class PacketBlock

git-svn-id: http://libopenmetaverse.googlecode.com/svn/trunk@2278 52acb1d6-8a22-11de-b505-999d5b087335
2008-10-08 17:08:17 +00:00

407 lines
14 KiB
C#

/*
* Copyright (c) 2008, openmetaverse.org
* All rights reserved.
*
* - Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* - Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
* - Neither the name of the Second Life Reverse Engineering Team nor the names
* of its contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
using System;
using System.Text;
using OpenMetaverse;
namespace OpenMetaverse.Packets
{
/// <summary>
/// Thrown when a packet could not be successfully deserialized
/// </summary>
public class MalformedDataException : ApplicationException
{
/// <summary>
/// Default constructor
/// </summary>
public MalformedDataException() { }
/// <summary>
/// Constructor that takes an additional error message
/// </summary>
/// <param name="Message">An error message to attach to this exception</param>
public MalformedDataException(string Message)
: base(Message)
{
this.Source = "Packet decoding";
}
}
/// <summary>
/// The header of a message template packet. Either 5, 6, or 8 bytes in
/// length at the beginning of the packet, and encapsulates any
/// appended ACKs at the end of the packet as well
/// </summary>
public abstract class Header
{
/// <summary>Raw header data, does not include appended ACKs</summary>
public byte[] Data;
/// <summary>Raw value of the flags byte</summary>
public byte Flags
{
get { return Data[0]; }
set { Data[0] = value; }
}
/// <summary>Reliable flag, whether this packet requires an ACK</summary>
public bool Reliable
{
get { return (Data[0] & Helpers.MSG_RELIABLE) != 0; }
set { if (value) { Data[0] |= (byte)Helpers.MSG_RELIABLE; } else { byte mask = (byte)Helpers.MSG_RELIABLE ^ 0xFF; Data[0] &= mask; } }
}
/// <summary>Resent flag, whether this same packet has already been
/// sent</summary>
public bool Resent
{
get { return (Data[0] & Helpers.MSG_RESENT) != 0; }
set { if (value) { Data[0] |= (byte)Helpers.MSG_RESENT; } else { byte mask = (byte)Helpers.MSG_RESENT ^ 0xFF; Data[0] &= mask; } }
}
/// <summary>Zerocoded flag, whether this packet is compressed with
/// zerocoding</summary>
public bool Zerocoded
{
get { return (Data[0] & Helpers.MSG_ZEROCODED) != 0; }
set { if (value) { Data[0] |= (byte)Helpers.MSG_ZEROCODED; } else { byte mask = (byte)Helpers.MSG_ZEROCODED ^ 0xFF; Data[0] &= mask; } }
}
/// <summary>Appended ACKs flag, whether this packet has ACKs appended
/// to the end</summary>
public bool AppendedAcks
{
get { return (Data[0] & Helpers.MSG_APPENDED_ACKS) != 0; }
set { if (value) { Data[0] |= (byte)Helpers.MSG_APPENDED_ACKS; } else { byte mask = (byte)Helpers.MSG_APPENDED_ACKS ^ 0xFF; Data[0] &= mask; } }
}
/// <summary>Packet sequence number</summary>
public uint Sequence
{
get { return (uint)((Data[1] << 24) + (Data[2] << 16) + (Data[3] << 8) + Data[4]); }
set
{
Data[1] = (byte)(value >> 24); Data[2] = (byte)(value >> 16);
Data[3] = (byte)(value >> 8); Data[4] = (byte)(value % 256);
}
}
/// <summary>Numeric ID number of this packet</summary>
public abstract ushort ID { get; set; }
/// <summary>Frequency classification of this packet, Low Medium or
/// High</summary>
public abstract PacketFrequency Frequency { get; }
/// <summary>Convert this header to a byte array, not including any
/// appended ACKs</summary>
public abstract void ToBytes(byte[] bytes, ref int i);
/// <summary>Array containing all the appended ACKs of this packet</summary>
public uint[] AckList;
public abstract void FromBytes(byte[] bytes, ref int pos, ref int packetEnd);
/// <summary>
/// Convert the AckList to a byte array, used for packet serializing
/// </summary>
/// <param name="bytes">Reference to the target byte array</param>
/// <param name="i">Beginning position to start writing to in the byte
/// array, will be updated with the ending position of the ACK list</param>
public void AcksToBytes(byte[] bytes, ref int i)
{
foreach (uint ack in AckList)
{
bytes[i++] = (byte)((ack >> 24) % 256);
bytes[i++] = (byte)((ack >> 16) % 256);
bytes[i++] = (byte)((ack >> 8) % 256);
bytes[i++] = (byte)(ack % 256);
}
if (AckList.Length > 0) { bytes[i++] = (byte)AckList.Length; }
}
/// <summary>
///
/// </summary>
/// <param name="bytes"></param>
/// <param name="pos"></param>
/// <param name="packetEnd"></param>
/// <returns></returns>
public static Header BuildHeader(byte[] bytes, ref int pos, ref int packetEnd)
{
if (bytes[6] == 0xFF)
{
if (bytes[7] == 0xFF)
{
return new LowHeader(bytes, ref pos, ref packetEnd);
}
else
{
return new MediumHeader(bytes, ref pos, ref packetEnd);
}
}
else
{
return new HighHeader(bytes, ref pos, ref packetEnd);
}
}
/// <summary>
///
/// </summary>
/// <param name="bytes"></param>
/// <param name="packetEnd"></param>
protected void CreateAckList(byte[] bytes, ref int packetEnd)
{
if (AppendedAcks)
{
try
{
int count = bytes[packetEnd--];
AckList = new uint[count];
for (int i = 0; i < count; i++)
{
AckList[i] = (uint)(
(bytes[(packetEnd - i * 4) - 3] << 24) |
(bytes[(packetEnd - i * 4) - 2] << 16) |
(bytes[(packetEnd - i * 4) - 1] << 8) |
(bytes[(packetEnd - i * 4) ]));
}
packetEnd -= (count * 4);
}
catch (Exception)
{
AckList = new uint[0];
throw new MalformedDataException();
}
}
else
{
AckList = new uint[0];
}
}
}
/// <summary>
///
/// </summary>
public class LowHeader : Header
{
/// <summary></summary>
public override ushort ID
{
get { return (ushort)((Data[8] << 8) + Data[9]); }
set { Data[8] = (byte)(value >> 8); Data[9] = (byte)(value % 256); }
}
/// <summary></summary>
public override PacketFrequency Frequency { get { return PacketFrequency.Low; } }
/// <summary>
///
/// </summary>
public LowHeader()
{
Data = new byte[10];
Data[6] = Data[7] = 0xFF;
AckList = new uint[0];
}
/// <summary>
///
/// </summary>
/// <param name="bytes"></param>
/// <param name="pos"></param>
/// <param name="packetEnd"></param>
public LowHeader(byte[] bytes, ref int pos, ref int packetEnd)
{
FromBytes(bytes, ref pos, ref packetEnd);
}
override public void FromBytes(byte[] bytes, ref int pos, ref int packetEnd)
{
if (bytes.Length < 10) { throw new MalformedDataException(); }
Data = new byte[10];
Buffer.BlockCopy(bytes, 0, Data, 0, 10);
if ((bytes[0] & Helpers.MSG_ZEROCODED) != 0 && bytes[8] == 0)
{
if (bytes[9] == 1)
{
Data[9] = bytes[10];
}
else
{
throw new MalformedDataException();
}
}
pos = 10;
CreateAckList(bytes, ref packetEnd);
}
/// <summary>
///
/// </summary>
/// <param name="bytes"></param>
/// <param name="i"></param>
public override void ToBytes(byte[] bytes, ref int i)
{
Buffer.BlockCopy(Data, 0, bytes, i, 10);
i += 10;
}
}
/// <summary>
///
/// </summary>
public class MediumHeader : Header
{
/// <summary></summary>
public override ushort ID
{
get { return (ushort)Data[7]; }
set { Data[7] = (byte)value; }
}
/// <summary></summary>
public override PacketFrequency Frequency { get { return PacketFrequency.Medium; } }
/// <summary>
///
/// </summary>
public MediumHeader()
{
Data = new byte[8];
Data[6] = 0xFF;
AckList = new uint[0];
}
/// <summary>
///
/// </summary>
/// <param name="bytes"></param>
/// <param name="pos"></param>
/// <param name="packetEnd"></param>
public MediumHeader(byte[] bytes, ref int pos, ref int packetEnd)
{
FromBytes(bytes, ref pos, ref packetEnd);
}
override public void FromBytes(byte[] bytes, ref int pos, ref int packetEnd)
{
if (bytes.Length < 8) { throw new MalformedDataException(); }
Data = new byte[8];
Buffer.BlockCopy(bytes, 0, Data, 0, 8);
pos = 8;
CreateAckList(bytes, ref packetEnd);
}
/// <summary>
///
/// </summary>
/// <param name="bytes"></param>
/// <param name="i"></param>
public override void ToBytes(byte[] bytes, ref int i)
{
Buffer.BlockCopy(Data, 0, bytes, i, 8);
i += 8;
}
}
/// <summary>
///
/// </summary>
public class HighHeader : Header
{
/// <summary></summary>
public override ushort ID
{
get { return (ushort)Data[6]; }
set { Data[6] = (byte)value; }
}
/// <summary></summary>
public override PacketFrequency Frequency { get { return PacketFrequency.High; } }
/// <summary>
///
/// </summary>
public HighHeader()
{
Data = new byte[7];
AckList = new uint[0];
}
/// <summary>
///
/// </summary>
/// <param name="bytes"></param>
/// <param name="pos"></param>
/// <param name="packetEnd"></param>
public HighHeader(byte[] bytes, ref int pos, ref int packetEnd)
{
FromBytes(bytes, ref pos, ref packetEnd);
}
override public void FromBytes(byte[] bytes, ref int pos, ref int packetEnd)
{
if (bytes.Length < 7) { throw new MalformedDataException(); }
Data = new byte[7];
Buffer.BlockCopy(bytes, 0, Data, 0, 7);
pos = 7;
CreateAckList(bytes, ref packetEnd);
}
/// <summary>
///
/// </summary>
/// <param name="bytes"></param>
/// <param name="i"></param>
public override void ToBytes(byte[] bytes, ref int i)
{
Buffer.BlockCopy(Data, 0, bytes, i, 7);
i += 7;
}
}
/// <summary>
/// A block of data in a packet. Packets are composed of one or more blocks,
/// each block containing one or more fields
/// </summary>
public abstract class PacketBlock
{
/// <summary>Current length of the data in this packet</summary>
public abstract int Length { get; }
/// <summary>
/// Create a block from a byte array
/// </summary>
/// <param name="bytes">Byte array containing the serialized block</param>
/// <param name="i">Starting position of the block in the byte array.
/// This will point to the data after the end of the block when the
/// call returns</param>
public abstract void FromBytes(byte[] bytes, ref int i);
/// <summary>
/// Serialize this block into a byte array
/// </summary>
/// <param name="bytes">Byte array to serialize this block into</param>
/// <param name="i">Starting position in the byte array to serialize to.
/// This will point to the position directly after the end of the
/// serialized block when the call returns</param>
public abstract void ToBytes(byte[] bytes, ref int i);
}