/*
* Copyright 2011 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 java.net.URI;
import java.nio.ByteBuffer;
import java.util.Arrays;
import java.util.Map;
import io.netty.buffer.ChannelBuffers;
import io.netty.channel.Channel;
import io.netty.channel.ChannelFuture;
import io.netty.handler.codec.http.DefaultHttpRequest;
import io.netty.handler.codec.http.HttpHeaders.Names;
import io.netty.handler.codec.http.HttpHeaders.Values;
import io.netty.handler.codec.http.HttpMethod;
import io.netty.handler.codec.http.HttpRequest;
import io.netty.handler.codec.http.HttpRequestEncoder;
import io.netty.handler.codec.http.HttpResponse;
import io.netty.handler.codec.http.HttpResponseDecoder;
import io.netty.handler.codec.http.HttpResponseStatus;
import io.netty.handler.codec.http.HttpVersion;
/**
* <p>
* Performs client 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 WebSocketClientHandshaker00 extends WebSocketClientHandshaker {
private byte[] expectedChallengeResponseBytes;
/**
* Constructor specifying the destination web socket location and version to initiate
*
* @param webSocketURL
* URL for web socket communications. e.g "ws://myhost.com/mypath". Subsequent web socket frames will be
* sent to this URL.
* @param version
* Version of web socket specification to use to connect to the server
* @param subprotocol
* Sub protocol request sent to the server.
* @param customHeaders
* Map of custom headers to add to the client request
*/
public WebSocketClientHandshaker00(URI webSocketURL, WebSocketVersion version, String subprotocol,
Map<String, String> customHeaders) {
super(webSocketURL, version, subprotocol, customHeaders);
}
/**
* <p>
* Sends the opening request to the server:
* </p>
*
* <pre>
* GET /demo HTTP/1.1
* Upgrade: WebSocket
* Connection: Upgrade
* Host: example.com
* Origin: http://example.com
* Sec-WebSocket-Key1: 4 @1 46546xW%0l 1 5
* Sec-WebSocket-Key2: 12998 5 Y3 1 .P00
*
* ^n:ds[4U
* </pre>
*
* @param channel
* Channel into which we can write our request
*/
@Override
public ChannelFuture handshake(Channel channel) {
// Make keys
int spaces1 = WebSocketUtil.randomNumber(1, 12);
int spaces2 = WebSocketUtil.randomNumber(1, 12);
int max1 = Integer.MAX_VALUE / spaces1;
int max2 = Integer.MAX_VALUE / spaces2;
int number1 = WebSocketUtil.randomNumber(0, max1);
int number2 = WebSocketUtil.randomNumber(0, max2);
int product1 = number1 * spaces1;
int product2 = number2 * spaces2;
String key1 = Integer.toString(product1);
String key2 = Integer.toString(product2);
key1 = insertRandomCharacters(key1);
key2 = insertRandomCharacters(key2);
key1 = insertSpaces(key1, spaces1);
key2 = insertSpaces(key2, spaces2);
byte[] key3 = WebSocketUtil.randomBytes(8);
ByteBuffer buffer = ByteBuffer.allocate(4);
buffer.putInt(number1);
byte[] number1Array = buffer.array();
buffer = ByteBuffer.allocate(4);
buffer.putInt(number2);
byte[] number2Array = buffer.array();
byte[] challenge = new byte[16];
System.arraycopy(number1Array, 0, challenge, 0, 4);
System.arraycopy(number2Array, 0, challenge, 4, 4);
System.arraycopy(key3, 0, challenge, 8, 8);
expectedChallengeResponseBytes = WebSocketUtil.md5(challenge);
// Get path
URI wsURL = getWebSocketUrl();
String path = wsURL.getPath();
if (wsURL.getQuery() != null && wsURL.getQuery().length() > 0) {
path = wsURL.getPath() + "?" + wsURL.getQuery();
}
// Format request
HttpRequest request = new DefaultHttpRequest(HttpVersion.HTTP_1_1, HttpMethod.GET, path);
request.addHeader(Names.UPGRADE, Values.WEBSOCKET);
request.addHeader(Names.CONNECTION, Values.UPGRADE);
request.addHeader(Names.HOST, wsURL.getHost());
request.addHeader(Names.ORIGIN, "http://" + wsURL.getHost());
request.addHeader(Names.SEC_WEBSOCKET_KEY1, key1);
request.addHeader(Names.SEC_WEBSOCKET_KEY2, key2);
if (getExpectedSubprotocol() != null && !getExpectedSubprotocol().equals("")) {
request.addHeader(Names.SEC_WEBSOCKET_PROTOCOL, getExpectedSubprotocol());
}
if (customHeaders != null) {
for (String header : customHeaders.keySet()) {
request.addHeader(header, customHeaders.get(header));
}
}
request.setContent(ChannelBuffers.copiedBuffer(key3));
ChannelFuture future = channel.write(request);
channel.getPipeline().replace(HttpRequestEncoder.class, "ws-encoder", new WebSocket00FrameEncoder());
return future;
}
/**
* <p>
* Process 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>
*
* @param channel
* Channel
* @param response
* HTTP response returned from the server for the request sent by beginOpeningHandshake00().
* @throws WebSocketHandshakeException
*/
@Override
public void finishHandshake(Channel channel, HttpResponse response) throws WebSocketHandshakeException {
final HttpResponseStatus status = new HttpResponseStatus(101, "WebSocket Protocol Handshake");
if (!response.getStatus().equals(status)) {
throw new WebSocketHandshakeException("Invalid handshake response status: " + response.getStatus());
}
String upgrade = response.getHeader(Names.UPGRADE);
if (upgrade == null || !upgrade.equals(Values.WEBSOCKET)) {
throw new WebSocketHandshakeException("Invalid handshake response upgrade: "
+ response.getHeader(Names.UPGRADE));
}
String connection = response.getHeader(Names.CONNECTION);
if (connection == null || !connection.equals(Values.UPGRADE)) {
throw new WebSocketHandshakeException("Invalid handshake response connection: "
+ response.getHeader(Names.CONNECTION));
}
byte[] challenge = response.getContent().array();
if (!Arrays.equals(challenge, expectedChallengeResponseBytes)) {
throw new WebSocketHandshakeException("Invalid challenge");
}
String protocol = response.getHeader(Names.SEC_WEBSOCKET_PROTOCOL);
setActualSubprotocol(protocol);
channel.getPipeline().replace(HttpResponseDecoder.class, "ws-decoder", new WebSocket00FrameDecoder());
setHandshakeComplete();
}
private String insertRandomCharacters(String key) {
int count = WebSocketUtil.randomNumber(1, 12);
char[] randomChars = new char[count];
int randCount = 0;
while (randCount < count) {
int rand = (int) (Math.random() * 0x7e + 0x21);
if (0x21 < rand && rand < 0x2f || 0x3a < rand && rand < 0x7e) {
randomChars[randCount] = (char) rand;
randCount += 1;
}
}
for (int i = 0; i < count; i++) {
int split = WebSocketUtil.randomNumber(0, key.length());
String part1 = key.substring(0, split);
String part2 = key.substring(split);
key = part1 + randomChars[i] + part2;
}
return key;
}
private String insertSpaces(String key, int spaces) {
for (int i = 0; i < spaces; i++) {
int split = WebSocketUtil.randomNumber(1, key.length() - 1);
String part1 = key.substring(0, split);
String part2 = key.substring(split);
key = part1 + " " + part2;
}
return key;
}
}