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Merge "MacAddress: light refactors and improve documentation"

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Treehugger Robot
2017-12-04 23:01:11 +00:00
committed by Gerrit Code Review
parent a9494954d9 84bb7fc761
commit d871cab32d
4 changed files with 271 additions and 126 deletions
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266
core/java/android/net/MacAddress.java
View File

@@ -16,17 +16,23 @@
package android.net;
import android.annotation.IntDef;
import android.os.Parcel;
import android.os.Parcelable;
import com.android.internal.util.BitUtils;
import com.android.internal.util.Preconditions;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.util.Arrays;
import java.util.Random;
import java.util.StringJoiner;
/**
* Represents a mac address.
* Representation of a MAC address.
*
* This class only supports 48 bits long addresses and does not support 64 bits long addresses.
* Instances of this class are immutable.
*
* @hide
*/
@@ -35,76 +41,102 @@ public final class MacAddress implements Parcelable {
private static final int ETHER_ADDR_LEN = 6;
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 MacAddress representing the unique broadcast MAC address.
*/
public static final MacAddress BROADCAST_ADDRESS = MacAddress.fromBytes(ETHER_ADDR_BROADCAST);
/** The zero mac address. */
/**
* The MacAddress zero MAC address.
* @hide
*/
public static final MacAddress ALL_ZEROS_ADDRESS = new MacAddress(0);
/** Represents categories of mac addresses. */
public enum MacAddressType {
UNICAST,
MULTICAST,
BROADCAST;
}
/** @hide */
@Retention(RetentionPolicy.SOURCE)
@IntDef(prefix = { "TYPE_" }, value = {
TYPE_UNKNOWN,
TYPE_UNICAST,
TYPE_MULTICAST,
TYPE_BROADCAST,
})
public @interface MacAddressType { }
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");
/** Indicates a MAC address of unknown type. */
public static final int TYPE_UNKNOWN = 0;
/** Indicates a MAC address is a unicast address. */
public static final int TYPE_UNICAST = 1;
/** Indicates a MAC address is a multicast address. */
public static final int TYPE_MULTICAST = 2;
/** Indicates a MAC address is the broadcast address. */
public static final int TYPE_BROADCAST = 3;
// Internal representation of the mac address as a single 8 byte long.
private static final long VALID_LONG_MASK = (1L << 48) - 1;
private static final long LOCALLY_ASSIGNED_MASK = MacAddress.fromString("2:0:0:0:0:0").mAddr;
private static final long MULTICAST_MASK = MacAddress.fromString("1:0:0:0:0:0").mAddr;
private static final long OUI_MASK = MacAddress.fromString("ff:ff:ff:0:0:0").mAddr;
private static final long NIC_MASK = MacAddress.fromString("0:0:0:ff:ff:ff").mAddr;
private static final MacAddress BASE_GOOGLE_MAC = MacAddress.fromString("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
// 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;
mAddr = (VALID_LONG_MASK & 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() {
/**
* Returns the type of this address.
*
* @return the int constant representing the MAC address type of this MacAddress.
*/
public @MacAddressType int addressType() {
if (equals(BROADCAST_ADDRESS)) {
return MacAddressType.BROADCAST;
return TYPE_BROADCAST;
}
if (isMulticastAddress()) {
return MacAddressType.MULTICAST;
return TYPE_MULTICAST;
}
return MacAddressType.UNICAST;
return TYPE_UNICAST;
}
/** Returns true if this MacAddress corresponds to a multicast address. */
/**
* @return true if this MacAddress is a multicast address.
* @hide
*/
public boolean isMulticastAddress() {
return (mAddr & MULTICAST_MASK) != 0;
}
/** Returns true if this MacAddress corresponds to a locally assigned address. */
/**
* @return true if this MacAddress is a locally assigned address.
*/
public boolean isLocallyAssigned() {
return (mAddr & LOCALLY_ASSIGNED_MASK) != 0;
}
/** Returns a byte array representation of this MacAddress. */
/**
* @return a byte array representation of this MacAddress.
*/
public byte[] toByteArray() {
return byteAddrFromLongAddr(mAddr);
}
@Override
public String toString() {
return stringAddrFromByteAddr(byteAddrFromLongAddr(mAddr));
return stringAddrFromLongAddr(mAddr);
}
/**
* @return a String representation of the OUI part of this MacAddres,
* with the lower 3 bytes constituting the NIC part replaced with 0.
*/
public String toSafeString() {
return stringAddrFromLongAddr(mAddr & OUI_MASK);
}
@Override
@@ -138,27 +170,50 @@ public final class MacAddress implements Parcelable {
}
};
/** Return true if the given byte array is not null and has the length of a mac address. */
/**
* Returns true if the given byte array is an valid MAC address.
* A valid byte array representation for a MacAddress is a non-null array of length 6.
*
* @param addr a byte array.
* @return true if the given byte array is not null and has the length of a MAC address.
*
* @hide
*/
public static boolean isMacAddress(byte[] addr) {
return addr != null && addr.length == ETHER_ADDR_LEN;
}
/**
* 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.
* Returns the MAC address type of the MAC address represented by the given byte array,
* or null if the given byte array does not represent a MAC address.
* A valid byte array representation for a MacAddress is a non-null array of length 6.
*
* @param addr a byte array representing a MAC address.
* @return the int constant representing the MAC address type of the MAC address represented
* by the given byte array, or type UNKNOWN if the byte array is not a valid MAC address.
*
* @hide
*/
public static MacAddressType macAddressType(byte[] addr) {
public static int macAddressType(byte[] addr) {
if (!isMacAddress(addr)) {
return null;
return TYPE_UNKNOWN;
}
return new MacAddress(addr).addressType();
return MacAddress.fromBytes(addr).addressType();
}
/** DOCME */
/**
* Converts a String representation of a MAC address to a byte array representation.
* A valid String representation for a MacAddress is a series of 6 values in the
* range [0,ff] printed in hexadecimal and joined by ':' characters.
*
* @param addr a String representation of a MAC address.
* @return the byte representation of the MAC address.
* @throws IllegalArgumentException if the given String is not a valid representation.
*
* @hide
*/
public static byte[] byteAddrFromStringAddr(String addr) {
if (addr == null) {
throw new IllegalArgumentException("cannot convert the null String");
}
Preconditions.checkNotNull(addr);
String[] parts = addr.split(":");
if (parts.length != ETHER_ADDR_LEN) {
throw new IllegalArgumentException(addr + " was not a valid MAC address");
@@ -174,20 +229,26 @@ public final class MacAddress implements Parcelable {
return bytes;
}
/** DOCME */
/**
* Converts a byte array representation of a MAC address to a String representation made
* of 6 hexadecimal numbers in [0,ff] joined by ':' characters.
* A valid byte array representation for a MacAddress is a non-null array of length 6.
*
* @param addr a byte array representation of a MAC address.
* @return the String representation of the MAC address.
* @throws IllegalArgumentException if the given byte array is not a valid representation.
*
* @hide
*/
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();
return String.format("%02x:%02x:%02x:%02x:%02x:%02x",
addr[0], addr[1], addr[2], addr[3], addr[4], addr[5]);
}
/** @hide */
public static byte[] byteAddrFromLongAddr(long addr) {
private static byte[] byteAddrFromLongAddr(long addr) {
byte[] bytes = new byte[ETHER_ADDR_LEN];
int index = ETHER_ADDR_LEN;
while (index-- > 0) {
@@ -197,8 +258,8 @@ public final class MacAddress implements Parcelable {
return bytes;
}
/** @hide */
public static long longAddrFromByteAddr(byte[] addr) {
private static long longAddrFromByteAddr(byte[] addr) {
Preconditions.checkNotNull(addr);
if (!isMacAddress(addr)) {
throw new IllegalArgumentException(
Arrays.toString(addr) + " was not a valid MAC address");
@@ -210,11 +271,10 @@ public final class MacAddress implements Parcelable {
return longAddr;
}
/** @hide */
public static long longAddrFromStringAddr(String addr) {
if (addr == null) {
throw new IllegalArgumentException("cannot convert the null String");
}
// Internal conversion function equivalent to longAddrFromByteAddr(byteAddrFromStringAddr(addr))
// that avoids the allocation of an intermediary byte[].
private static long longAddrFromStringAddr(String addr) {
Preconditions.checkNotNull(addr);
String[] parts = addr.split(":");
if (parts.length != ETHER_ADDR_LEN) {
throw new IllegalArgumentException(addr + " was not a valid MAC address");
@@ -231,32 +291,74 @@ public final class MacAddress implements Parcelable {
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();
// Internal conversion function equivalent to stringAddrFromByteAddr(byteAddrFromLongAddr(addr))
// that avoids the allocation of an intermediary byte[].
private static String stringAddrFromLongAddr(long addr) {
return String.format("%02x:%02x:%02x:%02x:%02x:%02x",
(addr >> 40) & 0xff,
(addr >> 32) & 0xff,
(addr >> 24) & 0xff,
(addr >> 16) & 0xff,
(addr >> 8) & 0xff,
addr & 0xff);
}
/**
* Returns a randomely generated mac address with the Android OUI value "DA-A1-19".
* The locally assigned bit is always set to 1.
* Creates a MacAddress from the given String representation. A valid String representation
* for a MacAddress is a series of 6 values in the range [0,ff] printed in hexadecimal
* and joined by ':' characters.
*
* @param addr a String representation of a MAC address.
* @return the MacAddress corresponding to the given String representation.
* @throws IllegalArgumentException if the given String is not a valid representation.
*/
public static MacAddress getRandomAddress() {
return getRandomAddress(BASE_ANDROID_MAC, new Random());
public static MacAddress fromString(String addr) {
return new MacAddress(longAddrFromStringAddr(addr));
}
/**
* 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.
* Creates a MacAddress from the given byte array representation.
* A valid byte array representation for a MacAddress is a non-null array of length 6.
*
* @param addr a byte array representation of a MAC address.
* @return the MacAddress corresponding to the given byte array representation.
* @throws IllegalArgumentException if the given byte array is not a valid representation.
*/
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);
public static MacAddress fromBytes(byte[] addr) {
return new MacAddress(longAddrFromByteAddr(addr));
}
/**
* Returns a generated MAC address whose 24 least significant bits constituting the
* NIC part of the address are randomly selected.
*
* The locally assigned bit is always set to 1. The multicast bit is always set to 0.
*
* @return a random locally assigned MacAddress.
*
* @hide
*/
public static MacAddress createRandomUnicastAddress() {
return createRandomUnicastAddress(BASE_GOOGLE_MAC, new Random());
}
/**
* Returns a randomly 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. The multicast bit is always set to 0.
*
* @param base a base MacAddress whose OUI is used for generating the random address.
* @param r a standard Java Random object used for generating the random address.
* @return a random locally assigned MacAddress.
*
* @hide
*/
public static MacAddress createRandomUnicastAddress(MacAddress base, Random r) {
long addr = (base.mAddr & OUI_MASK) | (NIC_MASK & r.nextLong());
addr = addr | LOCALLY_ASSIGNED_MASK;
addr = addr & ~MULTICAST_MASK;
return new MacAddress(addr);
}
// Convenience function for working around the lack of byte literals.

7
core/java/android/net/metrics/WakeupStats.java
View File

@@ -16,6 +16,7 @@
package android.net.metrics;
import android.net.MacAddress;
import android.os.Process;
import android.os.SystemClock;
import android.util.SparseIntArray;
@@ -80,13 +81,13 @@ public class WakeupStats {
}
switch (ev.dstHwAddr.addressType()) {
case UNICAST:
case MacAddress.TYPE_UNICAST:
l2UnicastCount++;
break;
case MULTICAST:
case MacAddress.TYPE_MULTICAST:
l2MulticastCount++;
break;
case BROADCAST:
case MacAddress.TYPE_BROADCAST:
l2BroadcastCount++;
break;
default: