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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up with different versions on classes on the class path).

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/*
 * Copyright 2014 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:
 *
 *   https://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 io.netty.handler.codec.socksx.v5;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.ByteBufUtil;
import io.netty.channel.ChannelHandlerContext;
import io.netty.handler.codec.DecoderException;
import io.netty.handler.codec.DecoderResult;
import io.netty.handler.codec.ReplayingDecoder;
import io.netty.handler.codec.socksx.SocksVersion;
import io.netty.handler.codec.socksx.v5.Socks5CommandResponseDecoder.State;
import io.netty.util.internal.ObjectUtil;
import io.netty.util.internal.UnstableApi;

import java.util.List;

/**
 * Decodes a single {@link Socks5CommandResponse} from the inbound {@link ByteBuf}s.
 * On successful decode, this decoder will forward the received data to the next handler, so that
 * other handler can remove or replace this decoder later.  On failed decode, this decoder will
 * discard the received data, so that other handler closes the connection later.
 */
public class Socks5CommandResponseDecoder extends ReplayingDecoder {

    @UnstableApi
    public enum State {
        INIT,
        SUCCESS,
        FAILURE
    }

    private final Socks5AddressDecoder addressDecoder;

    public Socks5CommandResponseDecoder() {
        this(Socks5AddressDecoder.DEFAULT);
    }

    public Socks5CommandResponseDecoder(Socks5AddressDecoder addressDecoder) {
        super(State.INIT);
        this.addressDecoder = ObjectUtil.checkNotNull(addressDecoder, "addressDecoder");
    }

    @Override
    protected void decode(ChannelHandlerContext ctx, ByteBuf in, List out) throws Exception {
        try {
            switch (state()) {
            case INIT: {
                final byte version = in.readByte();
                if (version != SocksVersion.SOCKS5.byteValue()) {
                    throw new DecoderException(
                            "unsupported version: " + version + " (expected: " + SocksVersion.SOCKS5.byteValue() + ')');
                }
                final Socks5CommandStatus status = Socks5CommandStatus.valueOf(in.readByte());
                in.skipBytes(1); // Reserved
                final Socks5AddressType addrType = Socks5AddressType.valueOf(in.readByte());
                final String addr = addressDecoder.decodeAddress(addrType, in);
                final int port = ByteBufUtil.readUnsignedShortBE(in);

                out.add(new DefaultSocks5CommandResponse(status, addrType, addr, port));
                checkpoint(State.SUCCESS);
            }
            case SUCCESS: {
                int readableBytes = actualReadableBytes();
                if (readableBytes > 0) {
                    out.add(in.readRetainedSlice(readableBytes));
                }
                break;
            }
            case FAILURE: {
                in.skipBytes(actualReadableBytes());
                break;
            }
            }
        } catch (Exception e) {
            fail(out, e);
        }
    }

    private void fail(List out, Exception cause) {
        if (!(cause instanceof DecoderException)) {
            cause = new DecoderException(cause);
        }

        checkpoint(State.FAILURE);

        Socks5Message m = new DefaultSocks5CommandResponse(
                Socks5CommandStatus.FAILURE, Socks5AddressType.IPv4, null, 0);
        m.setDecoderResult(DecoderResult.failure(cause));
        out.add(m);
    }
}