1 /*
2  * Copyright (C) 2024 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package com.android.server.connectivity.mdns;
18 
19 import static com.android.net.module.util.HexDump.toHexString;
20 
21 import android.annotation.NonNull;
22 import android.annotation.Nullable;
23 
24 import androidx.annotation.VisibleForTesting;
25 
26 import java.io.IOException;
27 import java.util.Arrays;
28 
29 /** An mDNS "KEY" record, which contains a public key for a name. See RFC 2535. */
30 @VisibleForTesting(otherwise = VisibleForTesting.PACKAGE_PRIVATE)
31 public class MdnsKeyRecord extends MdnsRecord {
32     @Nullable private byte[] rData;
33 
MdnsKeyRecord(@onNull String[] name, @NonNull MdnsPacketReader reader)34     public MdnsKeyRecord(@NonNull String[] name, @NonNull MdnsPacketReader reader)
35             throws IOException {
36         this(name, reader, false);
37     }
38 
MdnsKeyRecord(@onNull String[] name, @NonNull MdnsPacketReader reader, boolean isQuestion)39     public MdnsKeyRecord(@NonNull String[] name, @NonNull MdnsPacketReader reader,
40             boolean isQuestion) throws IOException {
41         super(name, TYPE_KEY, reader, isQuestion);
42     }
43 
MdnsKeyRecord(@onNull String[] name, boolean isUnicast)44     public MdnsKeyRecord(@NonNull String[] name, boolean isUnicast) {
45         super(name, TYPE_KEY,
46                 MdnsConstants.QCLASS_INTERNET | (isUnicast ? MdnsConstants.QCLASS_UNICAST : 0),
47                 0L /* receiptTimeMillis */, false /* cacheFlush */, 0L /* ttlMillis */);
48     }
49 
MdnsKeyRecord(@onNull String[] name, long receiptTimeMillis, boolean cacheFlush, long ttlMillis, @Nullable byte[] rData)50     public MdnsKeyRecord(@NonNull String[] name, long receiptTimeMillis, boolean cacheFlush,
51             long ttlMillis, @Nullable byte[] rData) {
52         super(name, TYPE_KEY, MdnsConstants.QCLASS_INTERNET, receiptTimeMillis, cacheFlush,
53                 ttlMillis);
54         if (rData != null) {
55             this.rData = Arrays.copyOf(rData, rData.length);
56         }
57     }
58     /** Returns the KEY RDATA in bytes **/
getRData()59     public byte[] getRData() {
60         if (rData == null) {
61             return null;
62         }
63         return Arrays.copyOf(rData, rData.length);
64     }
65 
66     @Override
readData(MdnsPacketReader reader)67     protected void readData(MdnsPacketReader reader) throws IOException {
68         rData = new byte[reader.getRemaining()];
69         reader.readBytes(rData);
70     }
71 
72     @Override
writeData(MdnsPacketWriter writer)73     protected void writeData(MdnsPacketWriter writer) throws IOException {
74         if (rData != null) {
75             writer.writeBytes(rData);
76         }
77     }
78 
79     @Override
toString()80     public String toString() {
81         return "KEY: " + toHexString(rData);
82     }
83 
84     @Override
hashCode()85     public int hashCode() {
86         return (super.hashCode() * 31) + Arrays.hashCode(rData);
87     }
88 
89     @Override
equals(@ullable Object other)90     public boolean equals(@Nullable Object other) {
91         if (this == other) {
92             return true;
93         }
94         if (!(other instanceof MdnsKeyRecord)) {
95             return false;
96         }
97 
98         return super.equals(other) && Arrays.equals(rData, ((MdnsKeyRecord) other).rData);
99     }
100 }