com.flysoloing.learning.network.netty.socksproxy.SocksServerHandler.java Source code

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Here is the source code for com.flysoloing.learning.network.netty.socksproxy.SocksServerHandler.java

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/*
 * 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.channel.ChannelHandler;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.handler.codec.socksx.SocksMessage;
import io.netty.handler.codec.socksx.v4.Socks4CommandRequest;
import io.netty.handler.codec.socksx.v4.Socks4CommandType;
import io.netty.handler.codec.socksx.v5.*;

@ChannelHandler.Sharable
public final class SocksServerHandler extends SimpleChannelInboundHandler<SocksMessage> {

    public static final SocksServerHandler INSTANCE = new SocksServerHandler();

    private SocksServerHandler() {
    }

    @Override
    public void channelRead0(ChannelHandlerContext ctx, SocksMessage socksRequest) throws Exception {
        switch (socksRequest.version()) {
        case SOCKS4a:
            Socks4CommandRequest socksV4CmdRequest = (Socks4CommandRequest) socksRequest;
            if (socksV4CmdRequest.type() == Socks4CommandType.CONNECT) {
                ctx.pipeline().addLast(new SocksServerConnectHandler());
                ctx.pipeline().remove(this);
                ctx.fireChannelRead(socksRequest);
            } else {
                ctx.close();
            }
            break;
        case SOCKS5:
            if (socksRequest instanceof Socks5InitialRequest) {
                // auth support example
                //ctx.pipeline().addFirst(new Socks5PasswordAuthRequestDecoder());
                //ctx.write(new DefaultSocks5AuthMethodResponse(Socks5AuthMethod.PASSWORD));
                ctx.pipeline().addFirst(new Socks5CommandRequestDecoder());
                ctx.write(new DefaultSocks5InitialResponse(Socks5AuthMethod.NO_AUTH));
            } else if (socksRequest instanceof Socks5PasswordAuthRequest) {
                ctx.pipeline().addFirst(new Socks5CommandRequestDecoder());
                ctx.write(new DefaultSocks5PasswordAuthResponse(Socks5PasswordAuthStatus.SUCCESS));
            } else if (socksRequest instanceof Socks5CommandRequest) {
                Socks5CommandRequest socks5CmdRequest = (Socks5CommandRequest) socksRequest;
                if (socks5CmdRequest.type() == Socks5CommandType.CONNECT) {
                    ctx.pipeline().addLast(new SocksServerConnectHandler());
                    ctx.pipeline().remove(this);
                    ctx.fireChannelRead(socksRequest);
                } else {
                    ctx.close();
                }
            } else {
                ctx.close();
            }
            break;
        case UNKNOWN:
            ctx.close();
            break;
        }
    }

    @Override
    public void channelReadComplete(ChannelHandlerContext ctx) {
        ctx.flush();
    }

    @Override
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable throwable) {
        throwable.printStackTrace();
        SocksServerUtils.closeOnFlush(ctx.channel());
    }
}