/*
* 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:
*
* 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 io.netty.handler.codec.socksx.v4;
import io.netty.buffer.ByteBuf;
import io.netty.buffer.ByteBufUtil;
import io.netty.channel.ChannelHandler.Sharable;
import io.netty.channel.ChannelHandlerContext;
import io.netty.handler.codec.MessageToByteEncoder;
import io.netty.util.NetUtil;
/**
* Encodes a {@link Socks4CommandRequest} into a {@link ByteBuf}.
*/
@Sharable
public final class Socks4ClientEncoder extends MessageToByteEncoder<Socks4CommandRequest> {
/**
* The singleton instance of {@link Socks4ClientEncoder}
*/
public static final Socks4ClientEncoder INSTANCE = new Socks4ClientEncoder();
private static final byte[] IPv4_DOMAIN_MARKER = {0x00, 0x00, 0x00, 0x01};
private Socks4ClientEncoder() { }
@Override
protected void encode(ChannelHandlerContext ctx, Socks4CommandRequest msg, ByteBuf out) throws Exception {
out.writeByte(msg.version().byteValue());
out.writeByte(msg.type().byteValue());
out.writeShort(msg.dstPort());
if (NetUtil.isValidIpV4Address(msg.dstAddr())) {
out.writeBytes(NetUtil.createByteArrayFromIpAddressString(msg.dstAddr()));
ByteBufUtil.writeAscii(out, msg.userId());
out.writeByte(0);
} else {
out.writeBytes(IPv4_DOMAIN_MARKER);
ByteBufUtil.writeAscii(out, msg.userId());
out.writeByte(0);
ByteBufUtil.writeAscii(out, msg.dstAddr());
out.writeByte(0);
}
}
}