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Diffstat (limited to 'services/tests/servicestests/src/android/net/IpUtilsTest.java')
| -rw-r--r-- | services/tests/servicestests/src/android/net/IpUtilsTest.java | 162 |
1 files changed, 162 insertions, 0 deletions
diff --git a/services/tests/servicestests/src/android/net/IpUtilsTest.java b/services/tests/servicestests/src/android/net/IpUtilsTest.java new file mode 100644 index 0000000..c2d1608 --- /dev/null +++ b/services/tests/servicestests/src/android/net/IpUtilsTest.java @@ -0,0 +1,162 @@ +/* + * 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 android.net.util.IpUtils; +import android.test.suitebuilder.annotation.SmallTest; + +import java.nio.ByteBuffer; + +import junit.framework.TestCase; + + +public class IpUtilsTest extends TestCase { + + 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)) + + @SmallTest + 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)); + } + + @SmallTest + 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)); + } +} |