/* * 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.dhcp; import android.net.NetworkUtils; import android.net.DhcpResults; import android.net.LinkAddress; import android.system.OsConstants; import android.test.suitebuilder.annotation.SmallTest; import junit.framework.TestCase; import java.net.Inet4Address; import java.nio.ByteBuffer; import static android.net.dhcp.DhcpPacket.*; public class DhcpPacketTest extends TestCase { private static Inet4Address SERVER_ADDR = (Inet4Address) NetworkUtils.numericToInetAddress("192.0.2.1"); private static Inet4Address CLIENT_ADDR = (Inet4Address) NetworkUtils.numericToInetAddress("192.0.2.234"); // Use our own empty address instead of Inet4Address.ANY or INADDR_ANY to ensure that the code // doesn't use == instead of equals when comparing addresses. private static Inet4Address ANY = (Inet4Address) NetworkUtils.numericToInetAddress("0.0.0.0"); private static byte[] CLIENT_MAC = new byte[] { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05 }; class TestDhcpPacket extends DhcpPacket { private byte mType; // TODO: Make this a map of option numbers to bytes instead. private byte[] mDomainBytes, mVendorInfoBytes, mLeaseTimeBytes, mNetmaskBytes; public TestDhcpPacket(byte type, Inet4Address clientIp, Inet4Address yourIp) { super(0xdeadbeef, (short) 0, clientIp, yourIp, INADDR_ANY, INADDR_ANY, CLIENT_MAC, true); mType = type; } public TestDhcpPacket(byte type) { this(type, INADDR_ANY, CLIENT_ADDR); } public TestDhcpPacket setDomainBytes(byte[] domainBytes) { mDomainBytes = domainBytes; return this; } public TestDhcpPacket setVendorInfoBytes(byte[] vendorInfoBytes) { mVendorInfoBytes = vendorInfoBytes; return this; } public TestDhcpPacket setLeaseTimeBytes(byte[] leaseTimeBytes) { mLeaseTimeBytes = leaseTimeBytes; return this; } public TestDhcpPacket setNetmaskBytes(byte[] netmaskBytes) { mNetmaskBytes = netmaskBytes; return this; } public ByteBuffer buildPacket(int encap, short unusedDestUdp, short unusedSrcUdp) { ByteBuffer result = ByteBuffer.allocate(MAX_LENGTH); fillInPacket(encap, CLIENT_ADDR, SERVER_ADDR, DHCP_CLIENT, DHCP_SERVER, result, DHCP_BOOTREPLY, false); return result; } public void finishPacket(ByteBuffer buffer) { addTlv(buffer, DHCP_MESSAGE_TYPE, mType); if (mDomainBytes != null) { addTlv(buffer, DHCP_DOMAIN_NAME, mDomainBytes); } if (mVendorInfoBytes != null) { addTlv(buffer, DHCP_VENDOR_CLASS_ID, mVendorInfoBytes); } if (mLeaseTimeBytes != null) { addTlv(buffer, DHCP_LEASE_TIME, mLeaseTimeBytes); } if (mNetmaskBytes != null) { addTlv(buffer, DHCP_SUBNET_MASK, mNetmaskBytes); } addTlvEnd(buffer); } // Convenience method. public ByteBuffer build() { // ENCAP_BOOTP packets don't contain ports, so just pass in 0. ByteBuffer pkt = buildPacket(ENCAP_BOOTP, (short) 0, (short) 0); pkt.flip(); return pkt; } } private void assertDomainAndVendorInfoParses( String expectedDomain, byte[] domainBytes, String expectedVendorInfo, byte[] vendorInfoBytes) { ByteBuffer packet = new TestDhcpPacket(DHCP_MESSAGE_TYPE_OFFER) .setDomainBytes(domainBytes) .setVendorInfoBytes(vendorInfoBytes) .build(); DhcpPacket offerPacket = DhcpPacket.decodeFullPacket(packet, ENCAP_BOOTP); assertEquals(expectedDomain, offerPacket.mDomainName); assertEquals(expectedVendorInfo, offerPacket.mVendorId); } @SmallTest public void testDomainName() throws Exception { byte[] nullByte = new byte[] { 0x00 }; byte[] twoNullBytes = new byte[] { 0x00, 0x00 }; byte[] nonNullDomain = new byte[] { (byte) 'g', (byte) 'o', (byte) 'o', (byte) '.', (byte) 'g', (byte) 'l' }; byte[] trailingNullDomain = new byte[] { (byte) 'g', (byte) 'o', (byte) 'o', (byte) '.', (byte) 'g', (byte) 'l', 0x00 }; byte[] embeddedNullsDomain = new byte[] { (byte) 'g', (byte) 'o', (byte) 'o', 0x00, 0x00, (byte) 'g', (byte) 'l' }; byte[] metered = "ANDROID_METERED".getBytes("US-ASCII"); byte[] meteredEmbeddedNull = metered.clone(); meteredEmbeddedNull[7] = (char) 0; byte[] meteredTrailingNull = metered.clone(); meteredTrailingNull[meteredTrailingNull.length - 1] = (char) 0; assertDomainAndVendorInfoParses("", nullByte, "\u0000", nullByte); assertDomainAndVendorInfoParses("", twoNullBytes, "\u0000\u0000", twoNullBytes); assertDomainAndVendorInfoParses("goo.gl", nonNullDomain, "ANDROID_METERED", metered); assertDomainAndVendorInfoParses("goo", embeddedNullsDomain, "ANDROID\u0000METERED", meteredEmbeddedNull); assertDomainAndVendorInfoParses("goo.gl", trailingNullDomain, "ANDROID_METERE\u0000", meteredTrailingNull); } private void assertLeaseTimeParses(boolean expectValid, Integer rawLeaseTime, long leaseTimeMillis, byte[] leaseTimeBytes) { TestDhcpPacket testPacket = new TestDhcpPacket(DHCP_MESSAGE_TYPE_OFFER); if (leaseTimeBytes != null) { testPacket.setLeaseTimeBytes(leaseTimeBytes); } ByteBuffer packet = testPacket.build(); DhcpPacket offerPacket = DhcpPacket.decodeFullPacket(packet, ENCAP_BOOTP); if (!expectValid) { assertNull(offerPacket); return; } assertEquals(rawLeaseTime, offerPacket.mLeaseTime); DhcpResults dhcpResults = offerPacket.toDhcpResults(); // Just check this doesn't crash. assertEquals(leaseTimeMillis, offerPacket.getLeaseTimeMillis()); } @SmallTest public void testLeaseTime() throws Exception { byte[] noLease = null; byte[] tooShortLease = new byte[] { 0x00, 0x00 }; byte[] tooLongLease = new byte[] { 0x00, 0x00, 0x00, 60, 0x01 }; byte[] zeroLease = new byte[] { 0x00, 0x00, 0x00, 0x00 }; byte[] tenSecondLease = new byte[] { 0x00, 0x00, 0x00, 10 }; byte[] oneMinuteLease = new byte[] { 0x00, 0x00, 0x00, 60 }; byte[] fiveMinuteLease = new byte[] { 0x00, 0x00, 0x01, 0x2c }; byte[] oneDayLease = new byte[] { 0x00, 0x01, 0x51, (byte) 0x80 }; byte[] maxIntPlusOneLease = new byte[] { (byte) 0x80, 0x00, 0x00, 0x01 }; byte[] infiniteLease = new byte[] { (byte) 0xff, (byte) 0xff, (byte) 0xff, (byte) 0xff }; assertLeaseTimeParses(true, null, 0, noLease); assertLeaseTimeParses(false, null, 0, tooShortLease); assertLeaseTimeParses(false, null, 0, tooLongLease); assertLeaseTimeParses(true, 0, 60 * 1000, zeroLease); assertLeaseTimeParses(true, 10, 60 * 1000, tenSecondLease); assertLeaseTimeParses(true, 60, 60 * 1000, oneMinuteLease); assertLeaseTimeParses(true, 300, 300 * 1000, fiveMinuteLease); assertLeaseTimeParses(true, 86400, 86400 * 1000, oneDayLease); assertLeaseTimeParses(true, -2147483647, 2147483649L * 1000, maxIntPlusOneLease); assertLeaseTimeParses(true, DhcpPacket.INFINITE_LEASE, 0, infiniteLease); } private void checkIpAddress(String expected, Inet4Address clientIp, Inet4Address yourIp, byte[] netmaskBytes) { checkIpAddress(expected, DHCP_MESSAGE_TYPE_OFFER, clientIp, yourIp, netmaskBytes); checkIpAddress(expected, DHCP_MESSAGE_TYPE_ACK, clientIp, yourIp, netmaskBytes); } private void checkIpAddress(String expected, byte type, Inet4Address clientIp, Inet4Address yourIp, byte[] netmaskBytes) { ByteBuffer packet = new TestDhcpPacket(type, clientIp, yourIp) .setNetmaskBytes(netmaskBytes) .build(); DhcpPacket offerPacket = DhcpPacket.decodeFullPacket(packet, ENCAP_BOOTP); DhcpResults results = offerPacket.toDhcpResults(); if (expected != null) { LinkAddress expectedAddress = new LinkAddress(expected); assertEquals(expectedAddress, results.ipAddress); } else { assertNull(results); } } @SmallTest public void testIpAddress() throws Exception { byte[] slash11Netmask = new byte[] { (byte) 0xff, (byte) 0xe0, 0x00, 0x00 }; byte[] slash24Netmask = new byte[] { (byte) 0xff, (byte) 0xff, (byte) 0xff, 0x00 }; byte[] invalidNetmask = new byte[] { (byte) 0xff, (byte) 0xfb, (byte) 0xff, 0x00 }; Inet4Address example1 = (Inet4Address) NetworkUtils.numericToInetAddress("192.0.2.1"); Inet4Address example2 = (Inet4Address) NetworkUtils.numericToInetAddress("192.0.2.43"); // A packet without any addresses is not valid. checkIpAddress(null, ANY, ANY, slash24Netmask); // ClientIP is used iff YourIP is not present. checkIpAddress("192.0.2.1/24", example2, example1, slash24Netmask); checkIpAddress("192.0.2.43/11", example2, ANY, slash11Netmask); checkIpAddress("192.0.2.43/11", ANY, example2, slash11Netmask); // Invalid netmasks are ignored. checkIpAddress(null, example2, ANY, invalidNetmask); // If there is no netmask, implicit netmasks are used. checkIpAddress("192.0.2.43/24", ANY, example2, null); } }