MacAddress follow-up: define the core of the class
Test: new unit test parts of $ runtest frameworks-net
Change-Id: I08c57d2d656802f7bdd7a93fde711a7e77247583
diff --git a/core/java/android/net/MacAddress.java b/core/java/android/net/MacAddress.java
index e76d17d..f6a69ba 100644
--- a/core/java/android/net/MacAddress.java
+++ b/core/java/android/net/MacAddress.java
@@ -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 @@
/**
* 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();
+ }
+
+ /** DOCME */
+ public static byte[] byteAddrFromStringAddr(String addr) {
+ if (addr == null) {
+ throw new IllegalArgumentException("cannot convert the null String");
}
- if ((addr[0] & 0x01) == 1) {
- return MacAddressType.MULTICAST;
+ String[] parts = addr.split(":");
+ if (parts.length != ETHER_ADDR_LEN) {
+ throw new IllegalArgumentException(addr + " was not a valid MAC address");
}
- return MacAddressType.UNICAST;
+ 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;
}
}
diff --git a/tests/net/java/android/net/MacAddressTest.java b/tests/net/java/android/net/MacAddressTest.java
index 3fa9c3a..fcbb9da 100644
--- a/tests/net/java/android/net/MacAddressTest.java
+++ b/tests/net/java/android/net/MacAddressTest.java
@@ -19,12 +19,14 @@
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 @@
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());
+ }
}
}
- static byte[] toByteArray(int[] in) {
+ @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) {
byte[] out = new byte[in.length];
for (int i = 0; i < in.length; i++) {
out[i] = (byte) in[i];