/*
* 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 io.netty.handler.codec.socks;
import io.netty.buffer.ByteBuf;
import io.netty.channel.ChannelHandlerContext;
import io.netty.handler.codec.ReplayingDecoder;
import io.netty.handler.codec.socks.SocksInitRequestDecoder.State;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
/**
* Decodes {@link ByteBuf}s into {@link SocksInitRequest}.
* Before returning SocksRequest decoder removes itself from pipeline.
*/
public class SocksInitRequestDecoder extends ReplayingDecoder<State> {
public SocksInitRequestDecoder() {
super(State.CHECK_PROTOCOL_VERSION);
}
@Override
protected void decode(ChannelHandlerContext ctx, ByteBuf byteBuf, List<Object> out) throws Exception {
switch (state()) {
case CHECK_PROTOCOL_VERSION: {
if (byteBuf.readByte() != SocksProtocolVersion.SOCKS5.byteValue()) {
out.add(SocksCommonUtils.UNKNOWN_SOCKS_REQUEST);
break;
}
checkpoint(State.READ_AUTH_SCHEMES);
}
case READ_AUTH_SCHEMES: {
final byte authSchemeNum = byteBuf.readByte();
final List<SocksAuthScheme> authSchemes;
if (authSchemeNum > 0) {
authSchemes = new ArrayList<SocksAuthScheme>(authSchemeNum);
for (int i = 0; i < authSchemeNum; i++) {
authSchemes.add(SocksAuthScheme.valueOf(byteBuf.readByte()));
}
} else {
authSchemes = Collections.emptyList();
}
out.add(new SocksInitRequest(authSchemes));
break;
}
default: {
throw new Error();
}
}
ctx.pipeline().remove(this);
}
enum State {
CHECK_PROTOCOL_VERSION,
READ_AUTH_SCHEMES
}
}