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 com.flysoloing.learning.network.netty.socksproxy; import io.netty.bootstrap.Bootstrap; import io.netty.channel.*; import io.netty.channel.socket.nio.NioSocketChannel; import io.netty.handler.codec.socksx.SocksMessage; import io.netty.handler.codec.socksx.v4.DefaultSocks4CommandResponse; import io.netty.handler.codec.socksx.v4.Socks4CommandRequest; import io.netty.handler.codec.socksx.v4.Socks4CommandStatus; import io.netty.handler.codec.socksx.v5.DefaultSocks5CommandResponse; import io.netty.handler.codec.socksx.v5.Socks5CommandRequest; import io.netty.handler.codec.socksx.v5.Socks5CommandStatus; import io.netty.util.concurrent.Future; import io.netty.util.concurrent.FutureListener; import io.netty.util.concurrent.Promise; @ChannelHandler.Sharable public final class SocksServerConnectHandler extends SimpleChannelInboundHandler<SocksMessage> { private final Bootstrap b = new Bootstrap(); @Override public void channelRead0(final ChannelHandlerContext ctx, final SocksMessage message) throws Exception { if (message instanceof Socks4CommandRequest) { final Socks4CommandRequest request = (Socks4CommandRequest) message; Promise<Channel> promise = ctx.executor().newPromise(); promise.addListener(new FutureListener<Channel>() { public void operationComplete(final Future<Channel> future) throws Exception { final Channel outboundChannel = future.getNow(); if (future.isSuccess()) { ChannelFuture responseFuture = ctx.channel() .writeAndFlush(new DefaultSocks4CommandResponse(Socks4CommandStatus.SUCCESS)); responseFuture.addListener(new ChannelFutureListener() { public void operationComplete(ChannelFuture channelFuture) { ctx.pipeline().remove(SocksServerConnectHandler.this); outboundChannel.pipeline().addLast(new RelayHandler(ctx.channel())); ctx.pipeline().addLast(new RelayHandler(outboundChannel)); } }); } else { ctx.channel().writeAndFlush( new DefaultSocks4CommandResponse(Socks4CommandStatus.REJECTED_OR_FAILED)); SocksServerUtils.closeOnFlush(ctx.channel()); } } }); final Channel inboundChannel = ctx.channel(); b.group(inboundChannel.eventLoop()).channel(NioSocketChannel.class) .option(ChannelOption.CONNECT_TIMEOUT_MILLIS, 10000).option(ChannelOption.SO_KEEPALIVE, true) .handler(new DirectClientHandler(promise)); b.connect(request.dstAddr(), request.dstPort()).addListener(new ChannelFutureListener() { public void operationComplete(ChannelFuture future) throws Exception { if (future.isSuccess()) { // Connection established use handler provided results } else { // Close the connection if the connection attempt has failed. ctx.channel().writeAndFlush( new DefaultSocks4CommandResponse(Socks4CommandStatus.REJECTED_OR_FAILED)); SocksServerUtils.closeOnFlush(ctx.channel()); } } }); } else if (message instanceof Socks5CommandRequest) { final Socks5CommandRequest request = (Socks5CommandRequest) message; Promise<Channel> promise = ctx.executor().newPromise(); promise.addListener(new FutureListener<Channel>() { public void operationComplete(final Future<Channel> future) throws Exception { final Channel outboundChannel = future.getNow(); if (future.isSuccess()) { ChannelFuture responseFuture = ctx.channel() .writeAndFlush(new DefaultSocks5CommandResponse(Socks5CommandStatus.SUCCESS, request.dstAddrType(), request.dstAddr(), request.dstPort())); responseFuture.addListener(new ChannelFutureListener() { public void operationComplete(ChannelFuture channelFuture) { ctx.pipeline().remove(SocksServerConnectHandler.this); outboundChannel.pipeline().addLast(new RelayHandler(ctx.channel())); ctx.pipeline().addLast(new RelayHandler(outboundChannel)); } }); } else { ctx.channel().writeAndFlush(new DefaultSocks5CommandResponse(Socks5CommandStatus.FAILURE, request.dstAddrType())); SocksServerUtils.closeOnFlush(ctx.channel()); } } }); final Channel inboundChannel = ctx.channel(); b.group(inboundChannel.eventLoop()).channel(NioSocketChannel.class) .option(ChannelOption.CONNECT_TIMEOUT_MILLIS, 10000).option(ChannelOption.SO_KEEPALIVE, true) .handler(new DirectClientHandler(promise)); b.connect(request.dstAddr(), request.dstPort()).addListener(new ChannelFutureListener() { public void operationComplete(ChannelFuture future) throws Exception { if (future.isSuccess()) { // Connection established use handler provided results } else { // Close the connection if the connection attempt has failed. ctx.channel().writeAndFlush(new DefaultSocks5CommandResponse(Socks5CommandStatus.FAILURE, request.dstAddrType())); SocksServerUtils.closeOnFlush(ctx.channel()); } } }); } else { ctx.close(); } } @Override public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception { SocksServerUtils.closeOnFlush(ctx.channel()); } }