Merge "MacAddress follow-up: define the core of the class" (d39a5035) · Commits · e / os / android_frameworks_base

core/java/android/net/MacAddress.java

+226 −14

Original line number	Diff line number	Diff line
		@@ -16,29 +16,128 @@

		package android.net;

		import com.android.internal.annotations.VisibleForTesting;
		import android.os.Parcel;
		import android.os.Parcelable;

		import com.android.internal.util.BitUtils;

		import java.util.Arrays;
		import java.util.Random;
		import java.util.StringJoiner;

		/**
		* Represents a mac address.
		*
		* @hide
		*/
		public final class MacAddress {

		// TODO: add isLocallyAssigned().
		// TODO: add getRandomAddress() factory method.
		public final class MacAddress implements Parcelable {

		private static final int ETHER_ADDR_LEN = 6;
		private static final byte FF = (byte) 0xff;
		@VisibleForTesting
		static final byte[] ETHER_ADDR_BROADCAST = { FF, FF, FF, FF, FF, FF };
		private static final byte[] ETHER_ADDR_BROADCAST = addr(0xff, 0xff, 0xff, 0xff, 0xff, 0xff);

		/** The broadcast mac address. */
		public static final MacAddress BROADCAST_ADDRESS = new MacAddress(ETHER_ADDR_BROADCAST);

		/** The zero mac address. */
		public static final MacAddress ALL_ZEROS_ADDRESS = new MacAddress(0);

		/** Represents categories of mac addresses. */
		public enum MacAddressType {
		UNICAST,
		MULTICAST,
		BROADCAST;
		}

		private static final long VALID_LONG_MASK = BROADCAST_ADDRESS.mAddr;
		private static final long LOCALLY_ASSIGNED_MASK = new MacAddress("2:0:0:0:0:0").mAddr;
		private static final long MULTICAST_MASK = new MacAddress("1:0:0:0:0:0").mAddr;
		private static final long OUI_MASK = new MacAddress("ff:ff:ff:0:0:0").mAddr;
		private static final long NIC_MASK = new MacAddress("0:0:0:ff:ff:ff").mAddr;
		private static final MacAddress BASE_ANDROID_MAC = new MacAddress("da:a1:19:0:0:0");

		// Internal representation of the mac address as a single 8 byte long.
		// The encoding scheme sets the two most significant bytes to 0. The 6 bytes of the
		// mac address are encoded in the 6 least significant bytes of the long, where the first
		// byte of the array is mapped to the 3rd highest logical byte of the long, the second
		// byte of the array is mapped to the 4th highest logical byte of the long, and so on.
		private final long mAddr;

		private MacAddress(long addr) {
		mAddr = addr;
		}

		/** Creates a MacAddress for the given byte representation. */
		public MacAddress(byte[] addr) {
		this(longAddrFromByteAddr(addr));
		}

		/** Creates a MacAddress for the given string representation. */
		public MacAddress(String addr) {
		this(longAddrFromByteAddr(byteAddrFromStringAddr(addr)));
		}

		/** Returns the MacAddressType of this MacAddress. */
		public MacAddressType addressType() {
		if (equals(BROADCAST_ADDRESS)) {
		return MacAddressType.BROADCAST;
		}
		if (isMulticastAddress()) {
		return MacAddressType.MULTICAST;
		}
		return MacAddressType.UNICAST;
		}

		/** Returns true if this MacAddress corresponds to a multicast address. */
		public boolean isMulticastAddress() {
		return (mAddr & MULTICAST_MASK) != 0;
		}

		/** Returns true if this MacAddress corresponds to a locally assigned address. */
		public boolean isLocallyAssigned() {
		return (mAddr & LOCALLY_ASSIGNED_MASK) != 0;
		}

		/** Returns a byte array representation of this MacAddress. */
		public byte[] toByteArray() {
		return byteAddrFromLongAddr(mAddr);
		}

		@Override
		public String toString() {
		return stringAddrFromByteAddr(byteAddrFromLongAddr(mAddr));
		}

		@Override
		public int hashCode() {
		return (int) ((mAddr >> 32) ^ mAddr);
		}

		@Override
		public boolean equals(Object o) {
		return (o instanceof MacAddress) && ((MacAddress) o).mAddr == mAddr;
		}

		@Override
		public void writeToParcel(Parcel out, int flags) {
		out.writeLong(mAddr);
		}

		@Override
		public int describeContents() {
		return 0;
		}

		public static final Parcelable.Creator<MacAddress> CREATOR =
		new Parcelable.Creator<MacAddress>() {
		public MacAddress createFromParcel(Parcel in) {
		return new MacAddress(in.readLong());
		}

		public MacAddress[] newArray(int size) {
		return new MacAddress[size];
		}
		};

		/** Return true if the given byte array is not null and has the length of a mac address. */
		public static boolean isMacAddress(byte[] addr) {
		return addr != null && addr.length == ETHER_ADDR_LEN;
		@@ -46,17 +145,130 @@ public final class MacAddress {

		/**
		* Return the MacAddressType of the mac address represented by the given byte array,
		* or null if the given byte array does not represent an mac address. */
		* or null if the given byte array does not represent an mac address.
		*/
		public static MacAddressType macAddressType(byte[] addr) {
		if (!isMacAddress(addr)) {
		return null;
		}
		if (Arrays.equals(addr, ETHER_ADDR_BROADCAST)) {
		return MacAddressType.BROADCAST;
		return new MacAddress(addr).addressType();
		}
		if ((addr[0] & 0x01) == 1) {
		return MacAddressType.MULTICAST;

		/** DOCME */
		public static byte[] byteAddrFromStringAddr(String addr) {
		if (addr == null) {
		throw new IllegalArgumentException("cannot convert the null String");
		}
		return MacAddressType.UNICAST;
		String[] parts = addr.split(":");
		if (parts.length != ETHER_ADDR_LEN) {
		throw new IllegalArgumentException(addr + " was not a valid MAC address");
		}
		byte[] bytes = new byte[ETHER_ADDR_LEN];
		for (int i = 0; i < ETHER_ADDR_LEN; i++) {
		int x = Integer.valueOf(parts[i], 16);
		if (x < 0 \|\| 0xff < x) {
		throw new IllegalArgumentException(addr + "was not a valid MAC address");
		}
		bytes[i] = (byte) x;
		}
		return bytes;
		}

		/** DOCME */
		public static String stringAddrFromByteAddr(byte[] addr) {
		if (!isMacAddress(addr)) {
		return null;
		}
		StringJoiner j = new StringJoiner(":");
		for (byte b : addr) {
		j.add(Integer.toHexString(BitUtils.uint8(b)));
		}
		return j.toString();
		}

		/** @hide */
		public static byte[] byteAddrFromLongAddr(long addr) {
		byte[] bytes = new byte[ETHER_ADDR_LEN];
		int index = ETHER_ADDR_LEN;
		while (index-- > 0) {
		bytes[index] = (byte) addr;
		addr = addr >> 8;
		}
		return bytes;
		}

		/** @hide */
		public static long longAddrFromByteAddr(byte[] addr) {
		if (!isMacAddress(addr)) {
		throw new IllegalArgumentException(
		Arrays.toString(addr) + " was not a valid MAC address");
		}
		long longAddr = 0;
		for (byte b : addr) {
		longAddr = (longAddr << 8) + BitUtils.uint8(b);
		}
		return longAddr;
		}

		/** @hide */
		public static long longAddrFromStringAddr(String addr) {
		if (addr == null) {
		throw new IllegalArgumentException("cannot convert the null String");
		}
		String[] parts = addr.split(":");
		if (parts.length != ETHER_ADDR_LEN) {
		throw new IllegalArgumentException(addr + " was not a valid MAC address");
		}
		long longAddr = 0;
		int index = ETHER_ADDR_LEN;
		while (index-- > 0) {
		int x = Integer.valueOf(parts[index], 16);
		if (x < 0 \|\| 0xff < x) {
		throw new IllegalArgumentException(addr + "was not a valid MAC address");
		}
		longAddr = x + (longAddr << 8);
		}
		return longAddr;
		}

		/** @hide */
		public static String stringAddrFromLongAddr(long addr) {
		addr = Long.reverseBytes(addr) >> 16;
		StringJoiner j = new StringJoiner(":");
		for (int i = 0; i < ETHER_ADDR_LEN; i++) {
		j.add(Integer.toHexString((byte) addr));
		addr = addr >> 8;
		}
		return j.toString();
		}

		/**
		* Returns a randomely generated mac address with the Android OUI value "DA-A1-19".
		* The locally assigned bit is always set to 1.
		*/
		public static MacAddress getRandomAddress() {
		return getRandomAddress(BASE_ANDROID_MAC, new Random());
		}

		/**
		* Returns a randomely generated mac address using the given Random object and the same
		* OUI values as the given MacAddress. The locally assigned bit is always set to 1.
		*/
		public static MacAddress getRandomAddress(MacAddress base, Random r) {
		long longAddr = (base.mAddr & OUI_MASK) \| (NIC_MASK & r.nextLong()) \| LOCALLY_ASSIGNED_MASK;
		return new MacAddress(longAddr);
		}

		// Convenience function for working around the lack of byte literals.
		private static byte[] addr(int... in) {
		if (in.length != ETHER_ADDR_LEN) {
		throw new IllegalArgumentException(Arrays.toString(in)
		+ " was not an array with length equal to " + ETHER_ADDR_LEN);
		}
		byte[] out = new byte[ETHER_ADDR_LEN];
		for (int i = 0; i < ETHER_ADDR_LEN; i++) {
		out[i] = (byte) in[i];
		}
		return out;
		}
		}

tests/net/java/android/net/MacAddressTest.java

+132 −1

Original line number	Diff line number	Diff line
		@@ -19,12 +19,14 @@ package android.net;
		import static org.junit.Assert.assertEquals;
		import static org.junit.Assert.assertTrue;
		import static org.junit.Assert.assertFalse;
		import static org.junit.Assert.fail;

		import android.net.MacAddress.MacAddressType;
		import android.support.test.filters.SmallTest;
		import android.support.test.runner.AndroidJUnit4;

		import java.util.Arrays;
		import java.util.Random;

		import org.junit.Test;
		import org.junit.runner.RunWith;
		@@ -64,10 +66,139 @@ public class MacAddressTest {
		String msg = String.format("expected type of %s to be %s, but got %s",
		Arrays.toString(t.addr), t.expected, got);
		assertEquals(msg, t.expected, got);

		if (got != null) {
		assertEquals(got, new MacAddress(t.addr).addressType());
		}
		}
		}

		@Test
		public void testIsMulticastAddress() {
		MacAddress[] multicastAddresses = {
		MacAddress.BROADCAST_ADDRESS,
		new MacAddress("07:00:d3:56:8a:c4"),
		new MacAddress("33:33:aa:bb:cc:dd"),
		};
		MacAddress[] unicastAddresses = {
		MacAddress.ALL_ZEROS_ADDRESS,
		new MacAddress("00:01:44:55:66:77"),
		new MacAddress("08:00:22:33:44:55"),
		new MacAddress("06:00:00:00:00:00"),
		};

		for (MacAddress mac : multicastAddresses) {
		String msg = mac.toString() + " expected to be a multicast address";
		assertTrue(msg, mac.isMulticastAddress());
		}
		for (MacAddress mac : unicastAddresses) {
		String msg = mac.toString() + " expected not to be a multicast address";
		assertFalse(msg, mac.isMulticastAddress());
		}
		}

		@Test
		public void testIsLocallyAssignedAddress() {
		MacAddress[] localAddresses = {
		new MacAddress("06:00:00:00:00:00"),
		new MacAddress("07:00:d3:56:8a:c4"),
		new MacAddress("33:33:aa:bb:cc:dd"),
		};
		MacAddress[] universalAddresses = {
		new MacAddress("00:01:44:55:66:77"),
		new MacAddress("08:00:22:33:44:55"),
		};

		for (MacAddress mac : localAddresses) {
		String msg = mac.toString() + " expected to be a locally assigned address";
		assertTrue(msg, mac.isLocallyAssigned());
		}
		for (MacAddress mac : universalAddresses) {
		String msg = mac.toString() + " expected not to be globally unique address";
		assertFalse(msg, mac.isLocallyAssigned());
		}
		}

		@Test
		public void testMacAddressConversions() {
		final int iterations = 10000;
		for (int i = 0; i < iterations; i++) {
		MacAddress mac = MacAddress.getRandomAddress();

		String stringRepr = mac.toString();
		byte[] bytesRepr = mac.toByteArray();

		assertEquals(mac, new MacAddress(stringRepr));
		assertEquals(mac, new MacAddress(bytesRepr));
		}
		}

		@Test
		public void testMacAddressRandomGeneration() {
		final int iterations = 1000;
		final String expectedAndroidOui = "da:a1:19";
		for (int i = 0; i < iterations; i++) {
		MacAddress mac = MacAddress.getRandomAddress();
		String stringRepr = mac.toString();

		assertTrue(stringRepr + " expected to be a locally assigned address",
		mac.isLocallyAssigned());
		assertTrue(stringRepr + " expected to begin with " + expectedAndroidOui,
		stringRepr.startsWith(expectedAndroidOui));
		}

		final Random r = new Random();
		final String anotherOui = "24:5f:78";
		final String expectedLocalOui = "26:5f:78";
		final MacAddress base = new MacAddress(anotherOui + ":0:0:0");
		for (int i = 0; i < iterations; i++) {
		MacAddress mac = MacAddress.getRandomAddress(base, r);
		String stringRepr = mac.toString();

		assertTrue(stringRepr + " expected to be a locally assigned address",
		mac.isLocallyAssigned());
		assertTrue(stringRepr + " expected to begin with " + expectedLocalOui,
		stringRepr.startsWith(expectedLocalOui));
		}
		}

		@Test
		public void testConstructorInputValidation() {
		String[] invalidStringAddresses = {
		null,
		"",
		"abcd",
		"1:2:3:4:5",
		"1:2:3:4:5:6:7",
		"10000:2:3:4:5:6",
		};

		for (String s : invalidStringAddresses) {
		try {
		MacAddress mac = new MacAddress(s);
		fail("new MacAddress(" + s + ") should have failed, but returned " + mac);
		} catch (IllegalArgumentException excepted) {
		}
		}

		byte[][] invalidBytesAddresses = {
		null,
		{},
		{1,2,3,4,5},
		{1,2,3,4,5,6,7},
		};

		for (byte[] b : invalidBytesAddresses) {
		try {
		MacAddress mac = new MacAddress(b);
		fail("new MacAddress(" + Arrays.toString(b)
		+ ") should have failed, but returned " + mac);
		} catch (IllegalArgumentException excepted) {
		}
		}
		}

		static byte[] toByteArray(int[] in) {
		static byte[] toByteArray(int... in) {
		byte[] out = new byte[in.length];
		for (int i = 0; i < in.length; i++) {
		out[i] = (byte) in[i];