org.apache.hudi.org.apache.hbase.thirdparty.io.netty.resolver.dns.DnsAddressDecoder Maven / Gradle / Ivy
/*
* Copyright 2018 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 org.apache.hbase.thirdparty.io.netty.resolver.dns;
import java.net.IDN;
import java.net.InetAddress;
import java.net.UnknownHostException;
import org.apache.hbase.thirdparty.io.netty.buffer.ByteBuf;
import org.apache.hbase.thirdparty.io.netty.buffer.ByteBufHolder;
import org.apache.hbase.thirdparty.io.netty.handler.codec.dns.DnsRawRecord;
import org.apache.hbase.thirdparty.io.netty.handler.codec.dns.DnsRecord;
/**
* Decodes an {@link InetAddress} from an A or AAAA {@link DnsRawRecord}.
*/
final class DnsAddressDecoder {
private static final int INADDRSZ4 = 4;
private static final int INADDRSZ6 = 16;
/**
* Decodes an {@link InetAddress} from an A or AAAA {@link DnsRawRecord}.
*
* @param record the {@link DnsRecord}, most likely a {@link DnsRawRecord}
* @param name the host name of the decoded address
* @param decodeIdn whether to convert {@code name} to a unicode host name
*
* @return the {@link InetAddress}, or {@code null} if {@code record} is not a {@link DnsRawRecord} or
* its content is malformed
*/
static InetAddress decodeAddress(DnsRecord record, String name, boolean decodeIdn) {
if (!(record instanceof DnsRawRecord)) {
return null;
}
final ByteBuf content = ((ByteBufHolder) record).content();
final int contentLen = content.readableBytes();
if (contentLen != INADDRSZ4 && contentLen != INADDRSZ6) {
return null;
}
final byte[] addrBytes = new byte[contentLen];
content.getBytes(content.readerIndex(), addrBytes);
try {
return InetAddress.getByAddress(decodeIdn ? IDN.toUnicode(name) : name, addrBytes);
} catch (UnknownHostException e) {
// Should never reach here.
throw new Error(e);
}
}
private DnsAddressDecoder() { }
}