//
// ========================================================================
// Copyright (c) 1995-2014 Mort Bay Consulting Pty. Ltd.
// ------------------------------------------------------------------------
// All rights reserved. This program and the accompanying materials
// are made available under the terms of the Eclipse Public License v1.0
// and Apache License v2.0 which accompanies this distribution.
//
// The Eclipse Public License is available at
// http://www.eclipse.org/legal/epl-v10.html
//
// The Apache License v2.0 is available at
// http://www.opensource.org/licenses/apache2.0.php
//
// You may elect to redistribute this code under either of these licenses.
// ========================================================================
//
package org.eclipse.jetty.websocket;
import java.io.IOException;
import org.eclipse.jetty.io.Buffer;
import org.eclipse.jetty.io.Buffers;
import org.eclipse.jetty.io.EndPoint;
import org.eclipse.jetty.util.log.Log;
import org.eclipse.jetty.util.log.Logger;
/* ------------------------------------------------------------ */
/**
* Parser the WebSocket protocol.
*
*/
public class WebSocketParserD06 implements WebSocketParser
{
private static final Logger LOG = Log.getLogger(WebSocketParserD06.class);
public enum State {
START(0), MASK(4), OPCODE(1), LENGTH_7(1), LENGTH_16(2), LENGTH_63(8), DATA(0), SKIP(1);
int _needs;
State(int needs)
{
_needs=needs;
}
int getNeeds()
{
return _needs;
}
}
private final WebSocketBuffers _buffers;
private final EndPoint _endp;
private final FrameHandler _handler;
private final boolean _masked;
private State _state;
private Buffer _buffer;
private byte _flags;
private byte _opcode;
private int _bytesNeeded;
private long _length;
private final byte[] _mask = new byte[4];
private int _m;
/* ------------------------------------------------------------ */
/**
* @param buffers The buffers to use for parsing. Only the {@link Buffers#getBuffer()} is used.
* This should be a direct buffer if binary data is mostly used or an indirect buffer if utf-8 data
* is mostly used.
* @param endp the endpoint
* @param handler the handler to notify when a parse event occurs
* @param masked whether masking should be handled
*/
public WebSocketParserD06(WebSocketBuffers buffers, EndPoint endp, FrameHandler handler, boolean masked)
{
_buffers=buffers;
_endp=endp;
_handler=handler;
_masked=masked;
_state=State.START;
}
/* ------------------------------------------------------------ */
public boolean isBufferEmpty()
{
return _buffer==null || _buffer.length()==0;
}
/* ------------------------------------------------------------ */
public Buffer getBuffer()
{
return _buffer;
}
/* ------------------------------------------------------------ */
/** Parse to next event.
* Parse to the next {@link WebSocketParser.FrameHandler} event or until no more data is
* available. Fill data from the {@link EndPoint} only as necessary.
* @return An indication of progress or otherwise. -1 indicates EOF, 0 indicates
* that no bytes were read and no messages parsed. A positive number indicates either
* the bytes filled or the messages parsed.
*/
public int parseNext()
{
if (_buffer==null)
_buffer=_buffers.getBuffer();
int total_filled=0;
int events=0;
// Loop until an datagram call back or can't fill anymore
while(true)
{
int available=_buffer.length();
// Fill buffer if we need a byte or need length
while (available<(_state==State.SKIP?1:_bytesNeeded))
{
// compact to mark (set at start of data)
_buffer.compact();
// if no space, then the data is too big for buffer
if (_buffer.space() == 0)
throw new IllegalStateException("FULL: "+_state+" "+_bytesNeeded+">"+_buffer.capacity());
// catch IOExceptions (probably EOF) and try to parse what we have
try
{
int filled=_endp.isOpen()?_endp.fill(_buffer):-1;
if (filled<=0)
return (total_filled+events)>0?(total_filled+events):filled;
total_filled+=filled;
available=_buffer.length();
}
catch(IOException e)
{
LOG.debug(e);
return (total_filled+events)>0?(total_filled+events):-1;
}
}
// if we are here, then we have sufficient bytes to process the current state.
// Parse the buffer byte by byte (unless it is STATE_DATA)
byte b;
while (_state!=State.DATA && available>=(_state==State.SKIP?1:_bytesNeeded))
{
switch (_state)
{
case START:
_state=_masked?State.MASK:State.OPCODE;
_bytesNeeded=_state.getNeeds();
continue;
case MASK:
_buffer.get(_mask,0,4);
available-=4;
_state=State.OPCODE;
_bytesNeeded=_state.getNeeds();
_m=0;
continue;
case OPCODE:
b=_buffer.get();
available--;
if (_masked)
b^=_mask[_m++%4];
_opcode=(byte)(b&0xf);
_flags=(byte)(0xf&(b>>4));
if (WebSocketConnectionD06.isControlFrame(_opcode)&&!WebSocketConnectionD06.isLastFrame(_flags))
{
_state=State.SKIP;
events++;
_handler.close(WebSocketConnectionD06.CLOSE_PROTOCOL,"fragmented control");
}
else
_state=State.LENGTH_7;
_bytesNeeded=_state.getNeeds();
continue;
case LENGTH_7:
b=_buffer.get();
available--;
if (_masked)
b^=_mask[_m++%4];
switch(b)
{
case 127:
_length=0;
_state=State.LENGTH_63;
_bytesNeeded=_state.getNeeds();
break;
case 126:
_length=0;
_state=State.LENGTH_16;
_bytesNeeded=_state.getNeeds();
break;
default:
_length=(0x7f&b);
_bytesNeeded=(int)_length;
_state=State.DATA;
}
continue;
case LENGTH_16:
b=_buffer.get();
available--;
if (_masked)
b^=_mask[_m++%4];
_length = _length*0x100 + (0xff&b);
if (--_bytesNeeded==0)
{
_bytesNeeded=(int)_length;
if (_length>_buffer.capacity())
{
_state=State.SKIP;
events++;
_handler.close(WebSocketConnectionD06.CLOSE_LARGE,"frame size "+_length+">"+_buffer.capacity());
}
else
{
_state=State.DATA;
}
}
continue;
case LENGTH_63:
b=_buffer.get();
available--;
if (_masked)
b^=_mask[_m++%4];
_length = _length*0x100 + (0xff&b);
if (--_bytesNeeded==0)
{
_bytesNeeded=(int)_length;
if (_length>=_buffer.capacity())
{
_state=State.SKIP;
events++;
_handler.close(WebSocketConnectionD06.CLOSE_LARGE,"frame size "+_length+">"+_buffer.capacity());
}
else
{
_state=State.DATA;
}
}
continue;
case SKIP:
int skip=Math.min(available,_bytesNeeded);
_buffer.skip(skip);
available-=skip;
_bytesNeeded-=skip;
if (_bytesNeeded==0)
_state=State.START;
}
}
if (_state==State.DATA && available>=_bytesNeeded)
{
Buffer data =_buffer.get(_bytesNeeded);
if (_masked)
{
if (data.array()==null)
data=_buffer.asMutableBuffer();
byte[] array = data.array();
final int end=data.putIndex();
for (int i=data.getIndex();i<end;i++)
array[i]^=_mask[_m++%4];
}
// System.err.printf("%s %s %s >>\n",TypeUtil.toHexString(_flags),TypeUtil.toHexString(_opcode),data.length());
events++;
_handler.onFrame(_flags, _opcode, data);
_bytesNeeded=0;
_state=State.START;
if (_buffer.length()==0)
{
_buffers.returnBuffer(_buffer);
_buffer=null;
}
return total_filled+events;
}
}
}
/* ------------------------------------------------------------ */
public void fill(Buffer buffer)
{
if (buffer!=null && buffer.length()>0)
{
if (_buffer==null)
_buffer=_buffers.getBuffer();
_buffer.put(buffer);
buffer.clear();
}
}
}