107 lines
3.3 KiB
Java
107 lines
3.3 KiB
Java
/*
|
|
* Copyright (C) 2020 The Android Open Source Project
|
|
*
|
|
* Licensed 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 com.android.testutils;
|
|
|
|
import android.net.util.PacketReader;
|
|
import android.os.Handler;
|
|
|
|
import androidx.annotation.NonNull;
|
|
import androidx.annotation.Nullable;
|
|
|
|
import com.android.net.module.util.ArrayTrackRecord;
|
|
|
|
import java.io.FileDescriptor;
|
|
import java.io.FileOutputStream;
|
|
import java.io.IOException;
|
|
import java.nio.ByteBuffer;
|
|
import java.util.Arrays;
|
|
import java.util.function.Predicate;
|
|
|
|
import kotlin.Lazy;
|
|
import kotlin.LazyKt;
|
|
|
|
/**
|
|
* A packet reader that runs on a TAP interface.
|
|
*
|
|
* It also implements facilities to reply to received packets.
|
|
*/
|
|
public class TapPacketReader extends PacketReader {
|
|
private final FileDescriptor mTapFd;
|
|
private final ArrayTrackRecord<byte[]> mReceivedPackets = new ArrayTrackRecord<>();
|
|
private final Lazy<ArrayTrackRecord<byte[]>.ReadHead> mReadHead =
|
|
LazyKt.lazy(mReceivedPackets::newReadHead);
|
|
|
|
public TapPacketReader(Handler h, FileDescriptor tapFd, int maxPacketSize) {
|
|
super(h, maxPacketSize);
|
|
mTapFd = tapFd;
|
|
}
|
|
|
|
@Override
|
|
protected FileDescriptor createFd() {
|
|
return mTapFd;
|
|
}
|
|
|
|
@Override
|
|
protected void handlePacket(byte[] recvbuf, int length) {
|
|
final byte[] newPacket = Arrays.copyOf(recvbuf, length);
|
|
if (!mReceivedPackets.add(newPacket)) {
|
|
throw new AssertionError("More than " + Integer.MAX_VALUE + " packets outstanding!");
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Get the next packet that was received on the interface.
|
|
*/
|
|
@Nullable
|
|
public byte[] popPacket(long timeoutMs) {
|
|
return mReadHead.getValue().poll(timeoutMs, packet -> true);
|
|
}
|
|
|
|
/**
|
|
* Get the next packet that was received on the interface and matches the specified filter.
|
|
*/
|
|
@Nullable
|
|
public byte[] popPacket(long timeoutMs, @NonNull Predicate<byte[]> filter) {
|
|
return mReadHead.getValue().poll(timeoutMs, filter::test);
|
|
}
|
|
|
|
/**
|
|
* Get the {@link ArrayTrackRecord} that records all packets received by the reader since its
|
|
* creation.
|
|
*/
|
|
public ArrayTrackRecord<byte[]> getReceivedPackets() {
|
|
return mReceivedPackets;
|
|
}
|
|
|
|
/*
|
|
* Send a response on the TAP interface.
|
|
*
|
|
* The passed ByteBuffer is flipped after use.
|
|
*
|
|
* @param packet The packet to send.
|
|
* @throws IOException if the interface can't be written to.
|
|
*/
|
|
public void sendResponse(final ByteBuffer packet) throws IOException {
|
|
try (FileOutputStream out = new FileOutputStream(mTapFd)) {
|
|
byte[] packetBytes = new byte[packet.limit()];
|
|
packet.get(packetBytes);
|
|
packet.flip(); // So we can reuse it in the future.
|
|
out.write(packetBytes);
|
|
}
|
|
}
|
|
}
|