Merge "Randomize the local Wifi IPv4 address" into pi-dev (046bb433) · Commits · e / os / android_frameworks_base

services/core/java/com/android/server/connectivity/tethering/OffloadController.java

+1 −0

Original line number	Diff line number	Diff line
		@@ -282,6 +282,7 @@ public class OffloadController {
		return stats;
		}

		@Override
		public void setInterfaceQuota(String iface, long quotaBytes) {
		mHandler.post(() -> {
		if (quotaBytes == ITetheringStatsProvider.QUOTA_UNLIMITED) {

services/core/java/com/android/server/connectivity/tethering/OffloadHardwareInterface.java

+1 −0

Original line number	Diff line number	Diff line
		@@ -355,6 +355,7 @@ public class OffloadHardwareInterface {
		boolean success;
		String errMsg;

		@Override
		public String toString() {
		if (success) {
		return "ok";

services/core/java/com/android/server/connectivity/tethering/TetherInterfaceStateMachine.java

+20 −6

Original line number	Diff line number	Diff line
		@@ -16,6 +16,8 @@

		package com.android.server.connectivity.tethering;

		import static android.net.util.NetworkConstants.asByte;
		import static android.net.util.NetworkConstants.FF;
		import static android.net.util.NetworkConstants.RFC7421_PREFIX_LENGTH;

		import android.net.ConnectivityManager;
		@@ -64,6 +66,7 @@ import java.util.Set;
		*/
		public class TetherInterfaceStateMachine extends StateMachine {
		private static final IpPrefix LINK_LOCAL_PREFIX = new IpPrefix("fe80::/64");
		private static final byte DOUG_ADAMS = (byte) 42;

		private static final String USB_NEAR_IFACE_ADDR = "192.168.42.129";
		private static final int USB_PREFIX_LENGTH = 24;
		@@ -204,7 +207,7 @@ public class TetherInterfaceStateMachine extends StateMachine {
		ipAsString = USB_NEAR_IFACE_ADDR;
		prefixLen = USB_PREFIX_LENGTH;
		} else if (mInterfaceType == ConnectivityManager.TETHERING_WIFI) {
		ipAsString = WIFI_HOST_IFACE_ADDR;
		ipAsString = getRandomWifiIPv4Address();
		prefixLen = WIFI_HOST_IFACE_PREFIX_LENGTH;
		} else {
		// Nothing to do, BT does this elsewhere.
		@@ -253,6 +256,16 @@ public class TetherInterfaceStateMachine extends StateMachine {
		return true;
		}

		private String getRandomWifiIPv4Address() {
		try {
		byte[] bytes = NetworkUtils.numericToInetAddress(WIFI_HOST_IFACE_ADDR).getAddress();
		bytes[3] = getRandomSanitizedByte(DOUG_ADAMS, asByte(0), asByte(1), FF);
		return InetAddress.getByAddress(bytes).getHostAddress();
		} catch (Exception e) {
		return WIFI_HOST_IFACE_ADDR;
		}
		}

		private boolean startIPv6() {
		mInterfaceParams = mDeps.getInterfaceParams(mIfaceName);
		if (mInterfaceParams == null) {
		@@ -757,7 +770,7 @@ public class TetherInterfaceStateMachine extends StateMachine {
		// Given a prefix like 2001:db8::/64 return an address like 2001:db8::1.
		private static Inet6Address getLocalDnsIpFor(IpPrefix localPrefix) {
		final byte[] dnsBytes = localPrefix.getRawAddress();
		dnsBytes[dnsBytes.length - 1] = getRandomNonZeroByte();
		dnsBytes[dnsBytes.length - 1] = getRandomSanitizedByte(DOUG_ADAMS, asByte(0), asByte(1));
		try {
		return Inet6Address.getByAddress(null, dnsBytes, 0);
		} catch (UnknownHostException e) {
		@@ -766,10 +779,11 @@ public class TetherInterfaceStateMachine extends StateMachine {
		}
		}

		private static byte getRandomNonZeroByte() {
		private static byte getRandomSanitizedByte(byte dflt, byte... excluded) {
		final byte random = (byte) (new Random()).nextInt();
		// Don't pick the subnet-router anycast address, since that might be
		// in use on the upstream already.
		return (random != 0) ? random : 0x1;
		for (int value : excluded) {
		if (random == value) return dflt;
		}
		return random;
		}
		}

services/net/java/android/net/util/NetworkConstants.java

+1 −1

Original line number	Diff line number	Diff line
		@@ -53,7 +53,7 @@ public final class NetworkConstants {

		public static final int ETHER_HEADER_LEN = 14;

		private static final byte FF = asByte(0xff);
		public static final byte FF = asByte(0xff);
		public static final byte[] ETHER_ADDR_BROADCAST = {
		FF, FF, FF, FF, FF, FF
		};