package org.webbitserver.netty;
import org.jboss.netty.channel.ChannelHandler;
import org.jboss.netty.handler.codec.http.HttpRequest;
import org.jboss.netty.handler.codec.http.HttpResponse;
import org.jboss.netty.handler.codec.http.HttpResponseStatus;
import org.webbitserver.helpers.Base64;
import java.nio.charset.Charset;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import static org.jboss.netty.handler.codec.http.HttpHeaders.Names.CONNECTION;
import static org.jboss.netty.handler.codec.http.HttpHeaders.Names.UPGRADE;
import static org.jboss.netty.handler.codec.http.HttpHeaders.Values.WEBSOCKET;
public class Hybi implements WebSocketVersion {
public static final String SEC_WEBSOCKET_VERSION = "Sec-WebSocket-Version";
public static final String SEC_WEBSOCKET_ACCEPT = "Sec-WebSocket-Accept";
public static final String SEC_WEBSOCKET_KEY = "Sec-WebSocket-Key";
public static final String SEC_WEBSOCKET_PROTOCOL = "Sec-WebSocket-Protocol";
private static final Charset ASCII = Charset.forName("ASCII");
private static final String ACCEPT_GUID = "258EAFA5-E914-47DA-95CA-C5AB0DC85B11";
private static final int MIN_HYBI_VERSION = 8;
private static final MessageDigest SHA1;
static {
try {
SHA1 = MessageDigest.getInstance("SHA1");
} catch (NoSuchAlgorithmException e) {
throw new InternalError("SHA-1 not supported on this platform");
}
}
private final HttpRequest req;
private final HttpResponse res;
public Hybi(HttpRequest req, HttpResponse res) {
this.req = req;
this.res = res;
}
@Override
public boolean matches() {
return getHybiVersion() != null;
}
@Override
public void prepareHandshakeResponse(NettyWebSocketConnection webSocketConnection) {
webSocketConnection.setHybiWebSocketVersion(getHybiVersion());
if (getHybiVersion() < MIN_HYBI_VERSION) {
res.setStatus(HttpResponseStatus.UPGRADE_REQUIRED);
res.setHeader(SEC_WEBSOCKET_VERSION, String.valueOf(MIN_HYBI_VERSION));
return;
}
String key = req.getHeader(SEC_WEBSOCKET_KEY);
if (key == null) {
res.setStatus(HttpResponseStatus.BAD_REQUEST);
return;
}
String accept = Base64.encode(sha1(key + ACCEPT_GUID));
res.setStatus(new HttpResponseStatus(101, "Switching Protocols"));
res.addHeader(UPGRADE, WEBSOCKET.toLowerCase());
res.addHeader(CONNECTION, UPGRADE);
res.addHeader(SEC_WEBSOCKET_ACCEPT, accept);
String webSocketProtocol = req.getHeader(SEC_WEBSOCKET_PROTOCOL);
if (webSocketProtocol != null) {
res.addHeader(SEC_WEBSOCKET_PROTOCOL, webSocketProtocol);
}
}
@Override
public ChannelHandler createDecoder() {
return HybiWebSocketFrameDecoder.serverSide();
}
@Override
public ChannelHandler createEncoder() {
return new HybiWebSocketFrameEncoder();
}
private Integer getHybiVersion() {
return req.containsHeader(SEC_WEBSOCKET_VERSION) ? Integer.parseInt(req.getHeader(SEC_WEBSOCKET_VERSION).trim()) : null;
}
private byte[] sha1(String s) {
return SHA1.digest(s.getBytes(ASCII));
}
}