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.client; import java.net.URI; import org.wyb.sows.websocket.SowsAuthHelper; import io.netty.bootstrap.Bootstrap; import io.netty.channel.Channel; import io.netty.channel.ChannelFuture; import io.netty.channel.ChannelFutureListener; import io.netty.channel.ChannelHandler; import io.netty.channel.ChannelHandlerContext; import io.netty.channel.ChannelInitializer; import io.netty.channel.ChannelOption; import io.netty.channel.ChannelPipeline; import io.netty.channel.SimpleChannelInboundHandler; import io.netty.channel.socket.SocketChannel; import io.netty.channel.socket.nio.NioSocketChannel; import io.netty.handler.codec.http.DefaultHttpHeaders; import io.netty.handler.codec.http.HttpClientCodec; import io.netty.handler.codec.http.HttpHeaders; import io.netty.handler.codec.http.HttpObjectAggregator; import io.netty.handler.codec.http.websocketx.WebSocketClientHandshakerFactory; import io.netty.handler.codec.http.websocketx.WebSocketVersion; import io.netty.handler.codec.socks.SocksCmdRequest; import io.netty.handler.codec.socks.SocksCmdResponse; import io.netty.handler.codec.socks.SocksCmdStatus; import io.netty.util.CharsetUtil; import io.netty.util.concurrent.Future; import io.netty.util.concurrent.GenericFutureListener; import io.netty.util.concurrent.Promise; @ChannelHandler.Sharable public final class SocksServerConnectHandler extends SimpleChannelInboundHandler<SocksCmdRequest> { private final String userName; private final String passcode; private final Bootstrap b = new Bootstrap(); private final URI bridgeServiceUri; public SocksServerConnectHandler(URI bridgeServiceUri, String userName, String passcode) { this.bridgeServiceUri = bridgeServiceUri; this.userName = userName; this.passcode = passcode; } @Override public void channelRead0(final ChannelHandlerContext ctx, final SocksCmdRequest request) throws Exception { if (request.host().equals("127.0.0.1") || request.host().equals("localhost")) { System.err.println("Not able to establish bridge. Inform proxy client."); ctx.channel().writeAndFlush(new SocksCmdResponse(SocksCmdStatus.FAILURE, request.addressType())); SocksServerUtils.closeOnFlush(ctx.channel()); } Promise<Channel> promise = ctx.executor().newPromise(); promise.addListener(new GenericFutureListener<Future<Channel>>() { @Override public void operationComplete(final Future<Channel> future) throws Exception { final Channel outboundChannel = future.getNow(); if (future.isSuccess()) { if (SocksServer.isDebug) { System.out.println("Bridge is established. Inform proxy client."); } SocksCmdResponse resp = new SocksCmdResponse(SocksCmdStatus.SUCCESS, request.addressType()); resp.setProtocolVersion(request.protocolVersion()); ctx.channel().writeAndFlush(resp).addListener(new ChannelFutureListener() { @Override public void operationComplete(ChannelFuture channelFuture) { ChannelPipeline pipeline = ctx.pipeline(); pipeline.remove(SocksServerConnectHandler.this); // ctx.pipeline().addLast(new StringByteCodec()); pipeline.addLast(new WebSocketRelayHandler(outboundChannel)); } }); } else { System.err.println("Not able to establish bridge. Inform proxy client."); ctx.channel() .writeAndFlush(new SocksCmdResponse(SocksCmdStatus.FAILURE, request.addressType())); SocksServerUtils.closeOnFlush(ctx.channel()); } } }); final Channel inboundChannel = ctx.channel(); // Add authentication headers HttpHeaders authHeader = new DefaultHttpHeaders(); authHeader.add(SowsAuthHelper.HEADER_SOWS_USER, this.userName); byte[] nonce = SowsAuthHelper.randomBytes(16); String seed = SowsAuthHelper.base64(nonce); authHeader.add(SowsAuthHelper.HEADER_SOWS_SEED, seed); byte[] sha1 = SowsAuthHelper.sha1((this.passcode + seed).getBytes(CharsetUtil.US_ASCII)); String token = SowsAuthHelper.base64(sha1); authHeader.add(SowsAuthHelper.HEADER_SOWS_TOKEN, token); // initiating websocket client handler final WebSocketClientHandler handler = new WebSocketClientHandler(WebSocketClientHandshakerFactory .newHandshaker(bridgeServiceUri, WebSocketVersion.V13, null, false, authHeader), promise, request.host(), request.port(), inboundChannel); b.group(inboundChannel.eventLoop()).channel(NioSocketChannel.class) .option(ChannelOption.CONNECT_TIMEOUT_MILLIS, 10000).option(ChannelOption.SO_KEEPALIVE, true) .handler(new ChannelInitializer<SocketChannel>() { @Override protected void initChannel(SocketChannel ch) { ChannelPipeline p = ch.pipeline(); p.addLast(new HttpClientCodec(), new HttpObjectAggregator(8192), handler); } }); if (SocksServer.isDebug) { System.out.println("Try to connect to bridge service."); } b.connect(bridgeServiceUri.getHost(), bridgeServiceUri.getPort()).addListener(new ChannelFutureListener() { @Override public void operationComplete(ChannelFuture future) throws Exception { if (future.isSuccess()) { // Connection established use handler provided results if (SocksServer.isDebug) { System.out.printf("Brige service connection is established. host=%s,port=%d \r\n", bridgeServiceUri.getHost(), bridgeServiceUri.getPort()); } } else { // Close the connection if the connection attempt has // failed. System.err.printf("Not able to connect bridge service! host=%s,port=%d \r\n", bridgeServiceUri.getHost(), bridgeServiceUri.getPort()); ctx.channel() .writeAndFlush(new SocksCmdResponse(SocksCmdStatus.FAILURE, request.addressType())); SocksServerUtils.closeOnFlush(ctx.channel()); } } }); } @Override public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception { cause.printStackTrace(); SocksServerUtils.closeOnFlush(ctx.channel()); } }