Java tutorial
/* * 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 org.wyb.sows.server; import static io.netty.handler.codec.http.HttpHeaders.Names.CONTENT_TYPE; import static io.netty.handler.codec.http.HttpHeaders.Names.HOST; import static io.netty.handler.codec.http.HttpMethod.GET; import static io.netty.handler.codec.http.HttpResponseStatus.BAD_REQUEST; import static io.netty.handler.codec.http.HttpResponseStatus.FORBIDDEN; import static io.netty.handler.codec.http.HttpResponseStatus.NOT_FOUND; import static io.netty.handler.codec.http.HttpResponseStatus.OK; import static io.netty.handler.codec.http.HttpResponseStatus.UNAUTHORIZED; import static io.netty.handler.codec.http.HttpVersion.HTTP_1_1; import java.io.UnsupportedEncodingException; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.wyb.sows.server.security.AuthHandler; import org.wyb.sows.websocket.SowsAuthHelper; import org.wyb.sows.websocket.SowsConnectCmd; import org.wyb.sows.websocket.SowsStatusType; import io.netty.bootstrap.Bootstrap; import io.netty.buffer.ByteBuf; import io.netty.buffer.Unpooled; import io.netty.channel.Channel; import io.netty.channel.ChannelFuture; import io.netty.channel.ChannelFutureListener; import io.netty.channel.ChannelHandlerContext; import io.netty.channel.ChannelOption; import io.netty.channel.SimpleChannelInboundHandler; 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.HttpHeaders; import io.netty.handler.codec.http.websocketx.BinaryWebSocketFrame; import io.netty.handler.codec.http.websocketx.CloseWebSocketFrame; import io.netty.handler.codec.http.websocketx.PingWebSocketFrame; import io.netty.handler.codec.http.websocketx.PongWebSocketFrame; import io.netty.handler.codec.http.websocketx.TextWebSocketFrame; import io.netty.handler.codec.http.websocketx.WebSocketFrame; import io.netty.handler.codec.http.websocketx.WebSocketServerHandshaker; import io.netty.handler.codec.http.websocketx.WebSocketServerHandshakerFactory; import io.netty.util.CharsetUtil; /** * Handles handshakes and messages */ public class WebSocketServerHandler extends SimpleChannelInboundHandler<Object> { final Logger logger = LoggerFactory.getLogger(WebSocketServerHandler.class); private static final String WEBSOCKET_PATH = "/websocket"; private WebSocketServerHandshaker handshaker; private volatile Channel outboundChannel; private boolean remoteConnect = false; private final AuthHandler authHandler; public WebSocketServerHandler(AuthHandler authHandler) { this.authHandler = authHandler; } @Override public void channelRead0(ChannelHandlerContext ctx, Object msg) { if (msg instanceof FullHttpRequest) { handleHttpRequest(ctx, (FullHttpRequest) msg); } else if (msg instanceof WebSocketFrame) { handleWebSocketFrame(ctx, (WebSocketFrame) msg); } } @Override public void channelReadComplete(ChannelHandlerContext ctx) { ctx.flush(); } private void handleHttpRequest(ChannelHandlerContext ctx, FullHttpRequest req) { // Handle a bad request. if (!req.getDecoderResult().isSuccess()) { sendHttpResponse(ctx, req, new DefaultFullHttpResponse(HTTP_1_1, BAD_REQUEST)); return; } // Allow only GET methods. if (req.getMethod() != GET) { sendHttpResponse(ctx, req, new DefaultFullHttpResponse(HTTP_1_1, FORBIDDEN)); return; } // Send the demo page and favicon.ico if ("/".equals(req.getUri())) { ByteBuf content = WebSocketServerIndexPage.getContent(getWebSocketLocation(req)); FullHttpResponse res = new DefaultFullHttpResponse(HTTP_1_1, OK, content); res.headers().set(CONTENT_TYPE, "text/html; charset=UTF-8"); HttpHeaders.setContentLength(res, content.readableBytes()); sendHttpResponse(ctx, req, res); return; } if ("/favicon.ico".equals(req.getUri())) { FullHttpResponse res = new DefaultFullHttpResponse(HTTP_1_1, NOT_FOUND); sendHttpResponse(ctx, req, res); return; } // check auth header if (req.headers().contains(SowsAuthHelper.HEADER_SOWS_USER) && req.headers().contains(SowsAuthHelper.HEADER_SOWS_TOKEN) && req.headers().contains(SowsAuthHelper.HEADER_SOWS_SEED)) { String user = req.headers().get(SowsAuthHelper.HEADER_SOWS_USER); String token = req.headers().get(SowsAuthHelper.HEADER_SOWS_TOKEN); String seed = req.headers().get(SowsAuthHelper.HEADER_SOWS_SEED); if (authHandler.login(user, token, seed) != AuthHandler.OK) { FullHttpResponse res = new DefaultFullHttpResponse(HTTP_1_1, UNAUTHORIZED); sendHttpResponse(ctx, req, res); return; } } else { FullHttpResponse res = new DefaultFullHttpResponse(HTTP_1_1, UNAUTHORIZED); sendHttpResponse(ctx, req, res); return; } // Handshake WebSocketServerHandshakerFactory wsFactory = new WebSocketServerHandshakerFactory(getWebSocketLocation(req), null, true); handshaker = wsFactory.newHandshaker(req); if (handshaker == null) { WebSocketServerHandshakerFactory.sendUnsupportedVersionResponse(ctx.channel()); } else { handshaker.handshake(ctx.channel(), req); } } private void handleWebSocketFrame(ChannelHandlerContext ctx, WebSocketFrame frame) { // Check for closing frame if (frame instanceof CloseWebSocketFrame) { handshaker.close(ctx.channel(), (CloseWebSocketFrame) frame.retain()); return; } if (frame instanceof PingWebSocketFrame) { ctx.channel().write(new PongWebSocketFrame(frame.content().retain())); return; } if (!(frame instanceof WebSocketFrame)) { throw new UnsupportedOperationException( String.format("%s frame types not supported", frame.getClass().getName())); } if (frame instanceof BinaryWebSocketFrame) { if (remoteConnect) { BinaryWebSocketFrame binFrame = (BinaryWebSocketFrame) frame; if (outboundChannel.isActive()) { outboundChannel.writeAndFlush(binFrame.content().retain()) .addListener(new ChannelFutureListener() { @Override public void operationComplete(ChannelFuture future) { if (future.isSuccess()) { ctx.channel().read(); } else { future.channel().close(); } } }); } } else { ctx.close(); } } else if (frame instanceof TextWebSocketFrame) { String request = ((TextWebSocketFrame) frame).text(); if (!remoteConnect) { SowsConnectCmd cmd = new SowsConnectCmd(); try { cmd.decode(request); } catch (UnsupportedEncodingException e) { e.printStackTrace(); ctx.close(); } String host = cmd.getHost(); int port = cmd.getPort(); final Channel inboundChannel = ctx.channel(); // invalid host if (host.equals("localhost") || host.equals("127.0.0.1")) { logger.warn("Invalid host. Target=" + host + ":" + port); WebSocketFrame frame2 = new TextWebSocketFrame(SowsStatusType.FAILED.stringValue()); inboundChannel.writeAndFlush(frame2).addListener(ChannelFutureListener.CLOSE); } // Start the connection attempt. Bootstrap b = new Bootstrap(); b.group(inboundChannel.eventLoop()).channel(ctx.channel().getClass()) .handler(new HexDumpProxyInitializer(inboundChannel, handshaker)) .option(ChannelOption.AUTO_READ, false); ChannelFuture f = b.connect(host, port); outboundChannel = f.channel(); f.addListener(new ChannelFutureListener() { @Override public void operationComplete(ChannelFuture future) { if (future.isSuccess()) { logger.info("Target connection is established. Target=" + host + ":" + port); WebSocketFrame frame = new TextWebSocketFrame(SowsStatusType.SUCCESS.stringValue()); inboundChannel.writeAndFlush(frame); // connection complete start to read first data inboundChannel.read(); } else { logger.warn("Not able to connect target. Target=" + host + ":" + port); WebSocketFrame frame = new TextWebSocketFrame(SowsStatusType.FAILED.stringValue()); inboundChannel.writeAndFlush(frame).addListener(ChannelFutureListener.CLOSE); } } }); remoteConnect = true; } else { logger.warn("Unknown SowsCmd! " + request); ctx.close(); } } } private static void sendHttpResponse(ChannelHandlerContext ctx, FullHttpRequest req, FullHttpResponse res) { // Generate an error page if response getStatus code is not OK (200). if (res.getStatus().code() != 200) { ByteBuf buf = Unpooled.copiedBuffer(res.getStatus().toString(), CharsetUtil.UTF_8); res.content().writeBytes(buf); buf.release(); HttpHeaders.setContentLength(res, res.content().readableBytes()); } // Send the response and close the connection if necessary. ChannelFuture f = ctx.channel().writeAndFlush(res); if (!HttpHeaders.isKeepAlive(req) || res.getStatus().code() != 200) { f.addListener(ChannelFutureListener.CLOSE); } } @Override public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) { cause.printStackTrace(); ctx.close(); } private static String getWebSocketLocation(FullHttpRequest req) { String location = req.headers().get(HOST) + WEBSOCKET_PATH; if (WebSocketServer.SSL) { return "wss://" + location; } else { return "ws://" + location; } } @Override public void channelInactive(ChannelHandlerContext ctx) { if (logger.isDebugEnabled()) { logger.debug("Websocket inbound inactive."); } if (outboundChannel != null) { closeOnFlush(outboundChannel); } } /** * Closes the specified channel after all queued write requests are flushed. */ static void closeOnFlush(Channel ch) { if (ch.isActive()) { ch.writeAndFlush(Unpooled.EMPTY_BUFFER).addListener(ChannelFutureListener.CLOSE); } } }