/*
* Copyright 2012 The Netty Project
*
* The Netty Project 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 io.netty.handler.codec.http.websocketx;
import io.netty.buffer.
ByteBuf;
import io.netty.buffer.
Unpooled;
import io.netty.channel.
Channel;
import io.netty.channel.
ChannelFuture;
import io.netty.channel.
ChannelPromise;
import io.netty.handler.codec.http.
DefaultFullHttpResponse;
import io.netty.handler.codec.http.
FullHttpRequest;
import io.netty.handler.codec.http.
FullHttpResponse;
import io.netty.handler.codec.http.
HttpHeaderNames;
import io.netty.handler.codec.http.
HttpHeaderValues;
import io.netty.handler.codec.http.
HttpHeaders;
import io.netty.handler.codec.http.
HttpResponseStatus;
import java.util.regex.
Pattern;
import static io.netty.handler.codec.http.
HttpVersion.
HTTP_1_1;
/**
* <p>
* Performs server side opening and closing handshakes for web socket specification version <a
* href="http://tools.ietf.org/html/draft-ietf-hybi-thewebsocketprotocol-00" >draft-ietf-hybi-thewebsocketprotocol-
* 00</a>
* </p>
* <p>
* A very large portion of this code was taken from the Netty 3.2 HTTP example.
* </p>
*/
public class
WebSocketServerHandshaker00 extends
WebSocketServerHandshaker {
private static final
Pattern BEGINNING_DIGIT =
Pattern.
compile("[^0-9]");
private static final
Pattern BEGINNING_SPACE =
Pattern.
compile("[^ ]");
/**
* Constructor specifying the destination web socket location
*
* @param webSocketURL
* URL for web socket communications. e.g "ws://myhost.com/mypath". Subsequent web socket frames will be
* sent to this URL.
* @param subprotocols
* CSV of supported protocols
* @param maxFramePayloadLength
* Maximum allowable frame payload length. Setting this value to your application's requirement may
* reduce denial of service attacks using long data frames.
*/
public
WebSocketServerHandshaker00(
String webSocketURL,
String subprotocols, int
maxFramePayloadLength) {
super(
WebSocketVersion.
V00,
webSocketURL,
subprotocols,
maxFramePayloadLength);
}
/**
* <p>
* Handle the web socket handshake for the web socket specification <a href=
* "http://tools.ietf.org/html/draft-ietf-hybi-thewebsocketprotocol-00">HyBi version 0</a> and lower. This standard
* is really a rehash of <a href="http://tools.ietf.org/html/draft-hixie-thewebsocketprotocol-76" >hixie-76</a> and
* <a href="http://tools.ietf.org/html/draft-hixie-thewebsocketprotocol-75" >hixie-75</a>.
* </p>
*
* <p>
* Browser request to the server:
* </p>
*
* <pre>
* GET /demo HTTP/1.1
* Upgrade: WebSocket
* Connection: Upgrade
* Host: example.com
* Origin: http://example.com
* Sec-WebSocket-Protocol: chat, sample
* Sec-WebSocket-Key1: 4 @1 46546xW%0l 1 5
* Sec-WebSocket-Key2: 12998 5 Y3 1 .P00
*
* ^n:ds[4U
* </pre>
*
* <p>
* Server response:
* </p>
*
* <pre>
* HTTP/1.1 101 WebSocket Protocol Handshake
* Upgrade: WebSocket
* Connection: Upgrade
* Sec-WebSocket-Origin: http://example.com
* Sec-WebSocket-Location: ws://example.com/demo
* Sec-WebSocket-Protocol: sample
*
* 8jKS'y:G*Co,Wxa-
* </pre>
*/
@
Override
protected
FullHttpResponse newHandshakeResponse(
FullHttpRequest req,
HttpHeaders headers) {
// Serve the WebSocket handshake request.
if (!
req.
headers().
containsValue(
HttpHeaderNames.
CONNECTION,
HttpHeaderValues.
UPGRADE, true)
|| !
HttpHeaderValues.
WEBSOCKET.
contentEqualsIgnoreCase(
req.
headers().
get(
HttpHeaderNames.
UPGRADE))) {
throw new
WebSocketHandshakeException("not a WebSocket handshake request: missing upgrade");
}
// Hixie 75 does not contain these headers while Hixie 76 does
boolean
isHixie76 =
req.
headers().
contains(
HttpHeaderNames.
SEC_WEBSOCKET_KEY1) &&
req.
headers().
contains(
HttpHeaderNames.
SEC_WEBSOCKET_KEY2);
// Create the WebSocket handshake response.
FullHttpResponse res = new
DefaultFullHttpResponse(
HTTP_1_1, new
HttpResponseStatus(101,
isHixie76 ? "WebSocket Protocol Handshake" : "Web Socket Protocol Handshake"));
if (
headers != null) {
res.
headers().
add(
headers);
}
res.
headers().
add(
HttpHeaderNames.
UPGRADE,
HttpHeaderValues.
WEBSOCKET);
res.
headers().
add(
HttpHeaderNames.
CONNECTION,
HttpHeaderValues.
UPGRADE);
// Fill in the headers and contents depending on handshake getMethod.
if (
isHixie76) {
// New handshake getMethod with a challenge:
res.
headers().
add(
HttpHeaderNames.
SEC_WEBSOCKET_ORIGIN,
req.
headers().
get(
HttpHeaderNames.
ORIGIN));
res.
headers().
add(
HttpHeaderNames.
SEC_WEBSOCKET_LOCATION,
uri());
String subprotocols =
req.
headers().
get(
HttpHeaderNames.
SEC_WEBSOCKET_PROTOCOL);
if (
subprotocols != null) {
String selectedSubprotocol =
selectSubprotocol(
subprotocols);
if (
selectedSubprotocol == null) {
if (
logger.
isDebugEnabled()) {
logger.
debug("Requested subprotocol(s) not supported: {}",
subprotocols);
}
} else {
res.
headers().
add(
HttpHeaderNames.
SEC_WEBSOCKET_PROTOCOL,
selectedSubprotocol);
}
}
// Calculate the answer of the challenge.
String key1 =
req.
headers().
get(
HttpHeaderNames.
SEC_WEBSOCKET_KEY1);
String key2 =
req.
headers().
get(
HttpHeaderNames.
SEC_WEBSOCKET_KEY2);
int
a = (int) (
Long.
parseLong(
BEGINNING_DIGIT.
matcher(
key1).
replaceAll("")) /
BEGINNING_SPACE.
matcher(
key1).
replaceAll("").
length());
int
b = (int) (
Long.
parseLong(
BEGINNING_DIGIT.
matcher(
key2).
replaceAll("")) /
BEGINNING_SPACE.
matcher(
key2).
replaceAll("").
length());
long
c =
req.
content().
readLong();
ByteBuf input =
Unpooled.
buffer(16);
input.
writeInt(
a);
input.
writeInt(
b);
input.
writeLong(
c);
res.
content().
writeBytes(
WebSocketUtil.
md5(
input.
array()));
} else {
// Old Hixie 75 handshake getMethod with no challenge:
res.
headers().
add(
HttpHeaderNames.
WEBSOCKET_ORIGIN,
req.
headers().
get(
HttpHeaderNames.
ORIGIN));
res.
headers().
add(
HttpHeaderNames.
WEBSOCKET_LOCATION,
uri());
String protocol =
req.
headers().
get(
HttpHeaderNames.
WEBSOCKET_PROTOCOL);
if (
protocol != null) {
res.
headers().
add(
HttpHeaderNames.
WEBSOCKET_PROTOCOL,
selectSubprotocol(
protocol));
}
}
return
res;
}
/**
* Echo back the closing frame
*
* @param channel
* Channel
* @param frame
* Web Socket frame that was received
*/
@
Override
public
ChannelFuture close(
Channel channel,
CloseWebSocketFrame frame,
ChannelPromise promise) {
return
channel.
writeAndFlush(
frame,
promise);
}
@
Override
protected
WebSocketFrameDecoder newWebsocketDecoder() {
return new
WebSocket00FrameDecoder(
maxFramePayloadLength());
}
@
Override
protected
WebSocketFrameEncoder newWebSocketEncoder() {
return new
WebSocket00FrameEncoder();
}
}