websocket-sharp/websocket-sharp/WsFrame.cs

684 lines
16 KiB
C#

#region License
/*
* WsFrame.cs
*
* The MIT License
*
* Copyright (c) 2012-2013 sta.blockhead
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#endregion
using System;
using System.IO;
using System.Collections;
using System.Collections.Generic;
using System.Text;
namespace WebSocketSharp {
internal class WsFrame : IEnumerable<byte>
{
#region Private Const Fields
private const int _readBufferLen = 1024;
#endregion
#region Private Constructors
private WsFrame()
{
}
#endregion
#region Public Constructors
public WsFrame(Opcode opcode, PayloadData payloadData)
: this(opcode, Mask.MASK, payloadData)
{
}
public WsFrame(Opcode opcode, Mask mask, PayloadData payloadData)
: this(Fin.FINAL, opcode, mask, payloadData)
{
}
public WsFrame(Fin fin, Opcode opcode, Mask mask, PayloadData payloadData)
: this(fin, opcode, mask, payloadData, false)
{
}
public WsFrame(
Fin fin, Opcode opcode, Mask mask, PayloadData payloadData, bool compressed)
{
if (payloadData.IsNull())
throw new ArgumentNullException("payloadData");
if (isControl(opcode) && payloadData.Length > 125)
throw new ArgumentOutOfRangeException("payloadData",
"The control frame must have a payload length of 125 bytes or less.");
if (!isFinal(fin) && isControl(opcode))
throw new ArgumentException("The control frame must not be fragmented.");
if (isControl(opcode) && compressed)
throw new ArgumentException("The control frame must not be compressed.");
Fin = fin;
Rsv1 = isData(opcode) && compressed ? Rsv.ON : Rsv.OFF;
Opcode = opcode;
Mask = mask;
PayloadData = payloadData;
init();
}
#endregion
#region Internal Properties
internal bool IsBinary {
get {
return isBinary(Opcode);
}
}
internal bool IsClose {
get {
return isClose(Opcode);
}
}
internal bool IsCompressed {
get {
return Rsv1 == Rsv.ON;
}
}
internal bool IsContinuation {
get {
return isContinuation(Opcode);
}
}
internal bool IsControl {
get {
return isControl(Opcode);
}
}
internal bool IsData {
get {
return isData(Opcode);
}
}
internal bool IsFinal {
get {
return isFinal(Fin);
}
}
internal bool IsFragmented {
get {
return !IsFinal || IsContinuation;
}
}
internal bool IsMasked {
get {
return isMasked(Mask);
}
}
internal bool IsPing {
get {
return isPing(Opcode);
}
}
internal bool IsPong {
get {
return isPong(Opcode);
}
}
internal bool IsText {
get {
return isText(Opcode);
}
}
internal ulong Length {
get {
return 2 + (ulong)(ExtPayloadLen.Length + MaskingKey.Length) + PayloadData.Length;
}
}
internal bool PerMessageCompressed {
get {
return IsData && IsCompressed;
}
set {
if (value && !IsData)
return;
Rsv1 = value ? Rsv.ON : Rsv.OFF;
}
}
#endregion
#region Public Properties
public Fin Fin { get; private set; }
public Rsv Rsv1 { get; private set; }
public Rsv Rsv2 { get; private set; }
public Rsv Rsv3 { get; private set; }
public Opcode Opcode { get; private set; }
public Mask Mask { get; private set; }
public byte PayloadLen { get; private set; }
public byte[] ExtPayloadLen { get; private set; }
public byte[] MaskingKey { get; private set; }
public PayloadData PayloadData { get; private set; }
#endregion
#region Private Methods
private static void dump(WsFrame frame)
{
var len = frame.Length;
var count = (long)(len / 4);
var remainder = (int)(len % 4);
int countDigit;
string countFmt;
if (count < 10000)
{
countDigit = 4;
countFmt = "{0,4}";
}
else if (count < 0x010000)
{
countDigit = 4;
countFmt = "{0,4:X}";
}
else if (count < 0x0100000000)
{
countDigit = 8;
countFmt = "{0,8:X}";
}
else
{
countDigit = 16;
countFmt = "{0,16:X}";
}
var spFmt = String.Format("{{0,{0}}}", countDigit);
var headerFmt = String.Format(@"
{0} 01234567 89ABCDEF 01234567 89ABCDEF
{0}+--------+--------+--------+--------+", spFmt);
var footerFmt = String.Format(" {0}+--------+--------+--------+--------+", spFmt);
Func<Action<string, string, string, string>> linePrinter = () =>
{
long lineCount = 0;
var lineFmt = String.Format(" {0}|{{1,8}} {{2,8}} {{3,8}} {{4,8}}|", countFmt);
return (arg1, arg2, arg3, arg4) =>
{
Console.WriteLine(lineFmt, ++lineCount, arg1, arg2, arg3, arg4);
};
};
var printLine = linePrinter();
Console.WriteLine(headerFmt, String.Empty);
var buffer = frame.ToByteArray();
int i, j;
for (i = 0; i <= count; i++)
{
j = i * 4;
if (i < count)
printLine(
Convert.ToString(buffer[j], 2).PadLeft(8, '0'),
Convert.ToString(buffer[j + 1], 2).PadLeft(8, '0'),
Convert.ToString(buffer[j + 2], 2).PadLeft(8, '0'),
Convert.ToString(buffer[j + 3], 2).PadLeft(8, '0'));
else if (remainder > 0)
printLine(
Convert.ToString(buffer[j], 2).PadLeft(8, '0'),
remainder >= 2 ? Convert.ToString(buffer[j + 1], 2).PadLeft(8, '0') : String.Empty,
remainder == 3 ? Convert.ToString(buffer[j + 2], 2).PadLeft(8, '0') : String.Empty,
String.Empty);
}
Console.WriteLine(footerFmt, String.Empty);
}
private void init()
{
Rsv2 = Rsv.OFF;
Rsv3 = Rsv.OFF;
setPayloadLen(PayloadData.Length);
if (IsMasked)
maskPayloadData();
else
MaskingKey = new byte[]{};
}
private static bool isBinary(Opcode opcode)
{
return opcode == Opcode.BINARY;
}
private static bool isClose(Opcode opcode)
{
return opcode == Opcode.CLOSE;
}
private static bool isContinuation(Opcode opcode)
{
return opcode == Opcode.CONT;
}
private static bool isControl(Opcode opcode)
{
return isClose(opcode) || isPing(opcode) || isPong(opcode);
}
private static bool isData(Opcode opcode)
{
return isText(opcode) || isBinary(opcode);
}
private static bool isFinal(Fin fin)
{
return fin == Fin.FINAL;
}
private static bool isMasked(Mask mask)
{
return mask == Mask.MASK;
}
private static bool isPing(Opcode opcode)
{
return opcode == Opcode.PING;
}
private static bool isPong(Opcode opcode)
{
return opcode == Opcode.PONG;
}
private static bool isText(Opcode opcode)
{
return opcode == Opcode.TEXT;
}
private void maskPayloadData()
{
var key = new byte[4];
var rand = new Random();
rand.NextBytes(key);
MaskingKey = key;
PayloadData.Mask(key);
}
private static WsFrame parse(byte[] header, Stream stream, bool unmask)
{
if (header.IsNull() || header.Length != 2)
return null;
var frame = readHeader(header);
readExtPayloadLen(stream, frame);
readMaskingKey(stream, frame);
readPayloadData(stream, frame, unmask);
return frame;
}
private static void print(WsFrame frame)
{
var len = frame.ExtPayloadLen.Length;
var extPayloadLen = len == 2
? frame.ExtPayloadLen.To<ushort>(ByteOrder.BIG).ToString()
: len == 8
? frame.ExtPayloadLen.To<ulong>(ByteOrder.BIG).ToString()
: String.Empty;
var masked = frame.IsMasked;
var maskingKey = masked
? BitConverter.ToString(frame.MaskingKey)
: String.Empty;
var opcode = frame.Opcode;
var payloadData = frame.PayloadData.Length == 0
? String.Empty
: masked || frame.IsFragmented || frame.IsBinary || frame.IsClose
? BitConverter.ToString(frame.PayloadData.ToByteArray())
: Encoding.UTF8.GetString(frame.PayloadData.ToByteArray());
var format = @"
FIN: {0}
RSV1: {1}
RSV2: {2}
RSV3: {3}
Opcode: {4}
MASK: {5}
Payload Len: {6}
Extended Payload Len: {7}
Masking Key: {8}
Payload Data: {9}";
Console.WriteLine(
format, frame.Fin, frame.Rsv1, frame.Rsv2, frame.Rsv3, opcode, frame.Mask, frame.PayloadLen, extPayloadLen, maskingKey, payloadData);
}
private static void readExtPayloadLen(Stream stream, WsFrame frame)
{
int length = frame.PayloadLen <= 125
? 0
: frame.PayloadLen == 126
? 2
: 8;
if (length == 0)
{
frame.ExtPayloadLen = new byte[]{};
return;
}
var extPayloadLen = stream.ReadBytes(length);
if (extPayloadLen.Length != length)
throw new IOException();
frame.ExtPayloadLen = extPayloadLen;
}
private static WsFrame readHeader(byte[] header)
{
// FIN
Fin fin = (header[0] & 0x80) == 0x80 ? Fin.FINAL : Fin.MORE;
// RSV1
Rsv rsv1 = (header[0] & 0x40) == 0x40 ? Rsv.ON : Rsv.OFF;
// RSV2
Rsv rsv2 = (header[0] & 0x20) == 0x20 ? Rsv.ON : Rsv.OFF;
// RSV3
Rsv rsv3 = (header[0] & 0x10) == 0x10 ? Rsv.ON : Rsv.OFF;
// Opcode
Opcode opcode = (Opcode)(header[0] & 0x0f);
// MASK
Mask mask = (header[1] & 0x80) == 0x80 ? Mask.MASK : Mask.UNMASK;
// Payload len
byte payloadLen = (byte)(header[1] & 0x7f);
return new WsFrame {
Fin = fin,
Rsv1 = rsv1,
Rsv2 = rsv2,
Rsv3 = rsv3,
Opcode = opcode,
Mask = mask,
PayloadLen = payloadLen
};
}
private static void readMaskingKey(Stream stream, WsFrame frame)
{
if (!isMasked(frame.Mask))
{
frame.MaskingKey = new byte[]{};
return;
}
var maskingKey = stream.ReadBytes(4);
if (maskingKey.Length != 4)
throw new IOException();
frame.MaskingKey = maskingKey;
}
private static void readPayloadData(Stream stream, WsFrame frame, bool unmask)
{
ulong length = frame.PayloadLen <= 125
? frame.PayloadLen
: frame.PayloadLen == 126
? frame.ExtPayloadLen.To<ushort>(ByteOrder.BIG)
: frame.ExtPayloadLen.To<ulong>(ByteOrder.BIG);
if (length == 0)
{
frame.PayloadData = new PayloadData();
return;
}
if (frame.PayloadLen > 126 && length > PayloadData.MaxLength)
throw new WebSocketException(CloseStatusCode.TOO_BIG);
var buffer = length <= (ulong)_readBufferLen
? stream.ReadBytes((int)length)
: stream.ReadBytes((long)length, _readBufferLen);
if (buffer.LongLength != (long)length)
throw new IOException();
var masked = isMasked(frame.Mask);
var payloadData = masked
? new PayloadData(buffer, true)
: new PayloadData(buffer);
if (masked && unmask)
{
payloadData.Mask(frame.MaskingKey);
frame.Mask = Mask.UNMASK;
frame.MaskingKey = new byte[]{};
}
frame.PayloadData = payloadData;
}
private void setPayloadLen(ulong length)
{
if (length < 126)
{
PayloadLen = (byte)length;
ExtPayloadLen = new byte[]{};
return;
}
if (length < 0x010000)
{
PayloadLen = (byte)126;
ExtPayloadLen = ((ushort)length).ToByteArray(ByteOrder.BIG);
return;
}
PayloadLen = (byte)127;
ExtPayloadLen = length.ToByteArray(ByteOrder.BIG);
}
private void unmaskPayloadData()
{
PayloadData.Mask(MaskingKey);
Mask = Mask.UNMASK;
MaskingKey = new byte[]{};
}
#endregion
#region Public Methods
public IEnumerator<byte> GetEnumerator()
{
foreach (byte b in ToByteArray())
yield return b;
}
public static WsFrame Parse(byte[] src)
{
return Parse(src, true);
}
public static WsFrame Parse(Stream stream)
{
return Parse(stream, true);
}
public static WsFrame Parse(byte[] src, bool unmask)
{
using (MemoryStream ms = new MemoryStream(src))
{
return Parse(ms, unmask);
}
}
public static WsFrame Parse(Stream stream, bool unmask)
{
return Parse(stream, unmask, null);
}
public static WsFrame Parse(Stream stream, bool unmask, Action<Exception> error)
{
WsFrame frame = null;
try
{
var header = stream.ReadBytes(2);
frame = parse(header, stream, unmask);
}
catch (Exception ex)
{
if (!error.IsNull())
error(ex);
}
return frame;
}
public static void ParseAsync(Stream stream, Action<WsFrame> completed)
{
ParseAsync(stream, true, completed, null);
}
public static void ParseAsync(Stream stream, Action<WsFrame> completed, Action<Exception> error)
{
ParseAsync(stream, true, completed, error);
}
public static void ParseAsync(
Stream stream, bool unmask, Action<WsFrame> completed, Action<Exception> error)
{
var header = new byte[2];
AsyncCallback callback = ar =>
{
WsFrame frame = null;
try
{
int readLen = stream.EndRead(ar);
if (readLen != 2)
{
if (readLen == 1)
header[1] = (byte)stream.ReadByte();
else
header = null;
}
frame = parse(header, stream, unmask);
}
catch (Exception ex)
{
if (!error.IsNull())
error(ex);
}
finally
{
if (!completed.IsNull())
completed(frame);
}
};
stream.BeginRead(header, 0, 2, callback, null);
}
public void Print(bool dumped)
{
if (dumped)
dump(this);
else
print(this);
}
public byte[] ToByteArray()
{
var buffer = new List<byte>();
int header = (int)Fin;
header = (header << 1) + (int)Rsv1;
header = (header << 1) + (int)Rsv2;
header = (header << 1) + (int)Rsv3;
header = (header << 4) + (int)Opcode;
header = (header << 1) + (int)Mask;
header = (header << 7) + (int)PayloadLen;
buffer.AddRange(((ushort)header).ToByteArray(ByteOrder.BIG));
if (PayloadLen >= 126)
buffer.AddRange(ExtPayloadLen);
if (IsMasked)
buffer.AddRange(MaskingKey);
if (PayloadLen > 0)
buffer.AddRange(PayloadData.ToByteArray());
return buffer.ToArray();
}
public override string ToString()
{
return BitConverter.ToString(ToByteArray());
}
#endregion
#region Explicitly Implemented Interface Members
IEnumerator IEnumerable.GetEnumerator()
{
return GetEnumerator();
}
#endregion
}
}