9229ed98e2
Motivation: Some codecs should be considered unstable as these are relative new. For this purpose we should introduce an annotation which these codecs should us to be marked as unstable in terms of API. Modifications: - Add UnstableApi annotation and use it on codecs that are not stable - Move http2.hpack to http2.internal.hpack as it is internal. Result: Better document unstable APIs.
121 lines
4.3 KiB
Java
121 lines
4.3 KiB
Java
/*
|
|
* Copyright 2015 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.dns;
|
|
|
|
import io.netty.buffer.ByteBuf;
|
|
import io.netty.channel.ChannelHandler;
|
|
import io.netty.channel.ChannelHandlerContext;
|
|
import io.netty.channel.socket.DatagramPacket;
|
|
import io.netty.handler.codec.CorruptedFrameException;
|
|
import io.netty.handler.codec.MessageToMessageDecoder;
|
|
import io.netty.util.internal.UnstableApi;
|
|
|
|
import java.net.InetSocketAddress;
|
|
import java.util.List;
|
|
|
|
import static io.netty.util.internal.ObjectUtil.checkNotNull;
|
|
|
|
/**
|
|
* Decodes a {@link DatagramPacket} into a {@link DatagramDnsResponse}.
|
|
*/
|
|
@UnstableApi
|
|
@ChannelHandler.Sharable
|
|
public class DatagramDnsResponseDecoder extends MessageToMessageDecoder<DatagramPacket> {
|
|
|
|
private final DnsRecordDecoder recordDecoder;
|
|
|
|
/**
|
|
* Creates a new decoder with {@linkplain DnsRecordDecoder#DEFAULT the default record decoder}.
|
|
*/
|
|
public DatagramDnsResponseDecoder() {
|
|
this(DnsRecordDecoder.DEFAULT);
|
|
}
|
|
|
|
/**
|
|
* Creates a new decoder with the specified {@code recordDecoder}.
|
|
*/
|
|
public DatagramDnsResponseDecoder(DnsRecordDecoder recordDecoder) {
|
|
this.recordDecoder = checkNotNull(recordDecoder, "recordDecoder");
|
|
}
|
|
|
|
@Override
|
|
protected void decode(ChannelHandlerContext ctx, DatagramPacket packet, List<Object> out) throws Exception {
|
|
final ByteBuf buf = packet.content();
|
|
|
|
final DnsResponse response = newResponse(packet, buf);
|
|
boolean success = false;
|
|
try {
|
|
final int questionCount = buf.readUnsignedShort();
|
|
final int answerCount = buf.readUnsignedShort();
|
|
final int authorityRecordCount = buf.readUnsignedShort();
|
|
final int additionalRecordCount = buf.readUnsignedShort();
|
|
|
|
decodeQuestions(response, buf, questionCount);
|
|
decodeRecords(response, DnsSection.ANSWER, buf, answerCount);
|
|
decodeRecords(response, DnsSection.AUTHORITY, buf, authorityRecordCount);
|
|
decodeRecords(response, DnsSection.ADDITIONAL, buf, additionalRecordCount);
|
|
|
|
out.add(response);
|
|
success = true;
|
|
} finally {
|
|
if (!success) {
|
|
response.release();
|
|
}
|
|
}
|
|
}
|
|
|
|
private static DnsResponse newResponse(DatagramPacket packet, ByteBuf buf) {
|
|
final int id = buf.readUnsignedShort();
|
|
|
|
final int flags = buf.readUnsignedShort();
|
|
if (flags >> 15 == 0) {
|
|
throw new CorruptedFrameException("not a response");
|
|
}
|
|
|
|
final DnsResponse response = new DatagramDnsResponse(
|
|
packet.sender(),
|
|
packet.recipient(),
|
|
id,
|
|
DnsOpCode.valueOf((byte) (flags >> 11 & 0xf)), DnsResponseCode.valueOf((byte) (flags & 0xf)));
|
|
|
|
response.setRecursionDesired((flags >> 8 & 1) == 1);
|
|
response.setAuthoritativeAnswer((flags >> 10 & 1) == 1);
|
|
response.setTruncated((flags >> 9 & 1) == 1);
|
|
response.setRecursionAvailable((flags >> 7 & 1) == 1);
|
|
response.setZ(flags >> 4 & 0x7);
|
|
return response;
|
|
}
|
|
|
|
private void decodeQuestions(DnsResponse response, ByteBuf buf, int questionCount) throws Exception {
|
|
for (int i = questionCount; i > 0; i --) {
|
|
response.addRecord(DnsSection.QUESTION, recordDecoder.decodeQuestion(buf));
|
|
}
|
|
}
|
|
|
|
private void decodeRecords(
|
|
DnsResponse response, DnsSection section, ByteBuf buf, int count) throws Exception {
|
|
for (int i = count; i > 0; i --) {
|
|
final DnsRecord r = recordDecoder.decodeRecord(buf);
|
|
if (r == null) {
|
|
// Truncated response
|
|
break;
|
|
}
|
|
|
|
response.addRecord(section, r);
|
|
}
|
|
}
|
|
}
|