167 lines
7.1 KiB
Java
167 lines
7.1 KiB
Java
/*
|
|
* Copyright (C) 2015 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 android.net.util;
|
|
|
|
import static org.junit.Assert.assertEquals;
|
|
|
|
import androidx.test.filters.SmallTest;
|
|
import androidx.test.runner.AndroidJUnit4;
|
|
|
|
import org.junit.Test;
|
|
import org.junit.runner.RunWith;
|
|
|
|
import java.nio.ByteBuffer;
|
|
|
|
@RunWith(AndroidJUnit4.class)
|
|
@SmallTest
|
|
public class IpUtilsTest {
|
|
|
|
private static final int IPV4_HEADER_LENGTH = 20;
|
|
private static final int IPV6_HEADER_LENGTH = 40;
|
|
private static final int TCP_HEADER_LENGTH = 20;
|
|
private static final int UDP_HEADER_LENGTH = 8;
|
|
private static final int IP_CHECKSUM_OFFSET = 10;
|
|
private static final int TCP_CHECKSUM_OFFSET = 16;
|
|
private static final int UDP_CHECKSUM_OFFSET = 6;
|
|
|
|
private int getUnsignedByte(ByteBuffer buf, int offset) {
|
|
return buf.get(offset) & 0xff;
|
|
}
|
|
|
|
private int getChecksum(ByteBuffer buf, int offset) {
|
|
return getUnsignedByte(buf, offset) * 256 + getUnsignedByte(buf, offset + 1);
|
|
}
|
|
|
|
private void assertChecksumEquals(int expected, short actual) {
|
|
assertEquals(Integer.toHexString(expected), Integer.toHexString(actual & 0xffff));
|
|
}
|
|
|
|
// Generate test packets using Python code like this::
|
|
//
|
|
// from scapy import all as scapy
|
|
//
|
|
// def JavaPacketDefinition(bytes):
|
|
// out = " ByteBuffer packet = ByteBuffer.wrap(new byte[] {\n "
|
|
// for i in xrange(len(bytes)):
|
|
// out += "(byte) 0x%02x" % ord(bytes[i])
|
|
// if i < len(bytes) - 1:
|
|
// if i % 4 == 3:
|
|
// out += ",\n "
|
|
// else:
|
|
// out += ", "
|
|
// out += "\n });"
|
|
// return out
|
|
//
|
|
// packet = (scapy.IPv6(src="2001:db8::1", dst="2001:db8::2") /
|
|
// scapy.UDP(sport=12345, dport=7) /
|
|
// "hello")
|
|
// print JavaPacketDefinition(str(packet))
|
|
|
|
@Test
|
|
public void testIpv6TcpChecksum() throws Exception {
|
|
// packet = (scapy.IPv6(src="2001:db8::1", dst="2001:db8::2", tc=0x80) /
|
|
// scapy.TCP(sport=12345, dport=7,
|
|
// seq=1692871236, ack=128376451, flags=16,
|
|
// window=32768) /
|
|
// "hello, world")
|
|
ByteBuffer packet = ByteBuffer.wrap(new byte[] {
|
|
(byte) 0x68, (byte) 0x00, (byte) 0x00, (byte) 0x00,
|
|
(byte) 0x00, (byte) 0x20, (byte) 0x06, (byte) 0x40,
|
|
(byte) 0x20, (byte) 0x01, (byte) 0x0d, (byte) 0xb8,
|
|
(byte) 0x00, (byte) 0x00, (byte) 0x00, (byte) 0x00,
|
|
(byte) 0x00, (byte) 0x00, (byte) 0x00, (byte) 0x00,
|
|
(byte) 0x00, (byte) 0x00, (byte) 0x00, (byte) 0x01,
|
|
(byte) 0x20, (byte) 0x01, (byte) 0x0d, (byte) 0xb8,
|
|
(byte) 0x00, (byte) 0x00, (byte) 0x00, (byte) 0x00,
|
|
(byte) 0x00, (byte) 0x00, (byte) 0x00, (byte) 0x00,
|
|
(byte) 0x00, (byte) 0x00, (byte) 0x00, (byte) 0x02,
|
|
(byte) 0x30, (byte) 0x39, (byte) 0x00, (byte) 0x07,
|
|
(byte) 0x64, (byte) 0xe7, (byte) 0x2a, (byte) 0x44,
|
|
(byte) 0x07, (byte) 0xa6, (byte) 0xde, (byte) 0x83,
|
|
(byte) 0x50, (byte) 0x10, (byte) 0x80, (byte) 0x00,
|
|
(byte) 0xee, (byte) 0x71, (byte) 0x00, (byte) 0x00,
|
|
(byte) 0x68, (byte) 0x65, (byte) 0x6c, (byte) 0x6c,
|
|
(byte) 0x6f, (byte) 0x2c, (byte) 0x20, (byte) 0x77,
|
|
(byte) 0x6f, (byte) 0x72, (byte) 0x6c, (byte) 0x64
|
|
});
|
|
|
|
// Check that a valid packet has checksum 0.
|
|
int transportLen = packet.limit() - IPV6_HEADER_LENGTH;
|
|
assertEquals(0, IpUtils.tcpChecksum(packet, 0, IPV6_HEADER_LENGTH, transportLen));
|
|
|
|
// Check that we can calculate the checksum from scratch.
|
|
int sumOffset = IPV6_HEADER_LENGTH + TCP_CHECKSUM_OFFSET;
|
|
int sum = getUnsignedByte(packet, sumOffset) * 256 + getUnsignedByte(packet, sumOffset + 1);
|
|
assertEquals(0xee71, sum);
|
|
|
|
packet.put(sumOffset, (byte) 0);
|
|
packet.put(sumOffset + 1, (byte) 0);
|
|
assertChecksumEquals(sum, IpUtils.tcpChecksum(packet, 0, IPV6_HEADER_LENGTH, transportLen));
|
|
|
|
// Check that writing the checksum back into the packet results in a valid packet.
|
|
packet.putShort(
|
|
sumOffset,
|
|
IpUtils.tcpChecksum(packet, 0, IPV6_HEADER_LENGTH, transportLen));
|
|
assertEquals(0, IpUtils.tcpChecksum(packet, 0, IPV6_HEADER_LENGTH, transportLen));
|
|
}
|
|
|
|
@Test
|
|
public void testIpv4UdpChecksum() {
|
|
// packet = (scapy.IP(src="192.0.2.1", dst="192.0.2.2", tos=0x40) /
|
|
// scapy.UDP(sport=32012, dport=4500) /
|
|
// "\xff")
|
|
ByteBuffer packet = ByteBuffer.wrap(new byte[] {
|
|
(byte) 0x45, (byte) 0x40, (byte) 0x00, (byte) 0x1d,
|
|
(byte) 0x00, (byte) 0x01, (byte) 0x00, (byte) 0x00,
|
|
(byte) 0x40, (byte) 0x11, (byte) 0xf6, (byte) 0x8b,
|
|
(byte) 0xc0, (byte) 0x00, (byte) 0x02, (byte) 0x01,
|
|
(byte) 0xc0, (byte) 0x00, (byte) 0x02, (byte) 0x02,
|
|
(byte) 0x7d, (byte) 0x0c, (byte) 0x11, (byte) 0x94,
|
|
(byte) 0x00, (byte) 0x09, (byte) 0xee, (byte) 0x36,
|
|
(byte) 0xff
|
|
});
|
|
|
|
// Check that a valid packet has IP checksum 0 and UDP checksum 0xffff (0 is not a valid
|
|
// UDP checksum, so the udpChecksum rewrites 0 to 0xffff).
|
|
assertEquals(0, IpUtils.ipChecksum(packet, 0));
|
|
assertEquals((short) 0xffff, IpUtils.udpChecksum(packet, 0, IPV4_HEADER_LENGTH));
|
|
|
|
// Check that we can calculate the checksums from scratch.
|
|
final int ipSumOffset = IP_CHECKSUM_OFFSET;
|
|
final int ipSum = getChecksum(packet, ipSumOffset);
|
|
assertEquals(0xf68b, ipSum);
|
|
|
|
packet.put(ipSumOffset, (byte) 0);
|
|
packet.put(ipSumOffset + 1, (byte) 0);
|
|
assertChecksumEquals(ipSum, IpUtils.ipChecksum(packet, 0));
|
|
|
|
final int udpSumOffset = IPV4_HEADER_LENGTH + UDP_CHECKSUM_OFFSET;
|
|
final int udpSum = getChecksum(packet, udpSumOffset);
|
|
assertEquals(0xee36, udpSum);
|
|
|
|
packet.put(udpSumOffset, (byte) 0);
|
|
packet.put(udpSumOffset + 1, (byte) 0);
|
|
assertChecksumEquals(udpSum, IpUtils.udpChecksum(packet, 0, IPV4_HEADER_LENGTH));
|
|
|
|
// Check that writing the checksums back into the packet results in a valid packet.
|
|
packet.putShort(ipSumOffset, IpUtils.ipChecksum(packet, 0));
|
|
packet.putShort(udpSumOffset, IpUtils.udpChecksum(packet, 0, IPV4_HEADER_LENGTH));
|
|
assertEquals(0, IpUtils.ipChecksum(packet, 0));
|
|
assertEquals((short) 0xffff, IpUtils.udpChecksum(packet, 0, IPV4_HEADER_LENGTH));
|
|
}
|
|
}
|