Merge "Use lower of IPv4/IPv6 MTU values based on config" (86540511) · Commits · e / os / android_frameworks_opt_telephony

src/java/com/android/internal/telephony/dataconnection/DataConnection.java

+25 −1

Original line number	Diff line number	Diff line
		@@ -127,6 +127,8 @@ public class DataConnection extends StateMachine {
		private static final String RAT_NAME_5G = "nr";
		private static final String RAT_NAME_EVDO = "evdo";

		private static final int MIN_V6_MTU = 1280;

		/**
		* The data connection is not being or been handovered. Note this is the state for the source
		* data connection, not destination data connection
		@@ -1603,9 +1605,31 @@ public class DataConnection extends StateMachine {
		}
		}

		boolean useLowerMtuValue = false;
		CarrierConfigManager configManager = (CarrierConfigManager)
		mPhone.getContext().getSystemService(Context.CARRIER_CONFIG_SERVICE);
		if (configManager != null) {
		PersistableBundle bundle = configManager.getConfigForSubId(mSubId);
		if (bundle != null) {
		useLowerMtuValue = bundle.getBoolean(
		CarrierConfigManager.KEY_USE_LOWER_MTU_VALUE_IF_BOTH_RECEIVED)
		&& response.getMtuV4() != PhoneConstants.UNSET_MTU
		&& response.getMtuV6() != PhoneConstants.UNSET_MTU;
		}
		}

		int interfaceMtu = response.getMtu();
		for (InetAddress gateway : response.getGatewayAddresses()) {
		int mtu = gateway instanceof java.net.Inet6Address ? response.getMtuV6()
		: response.getMtuV4();
		if (useLowerMtuValue) {
		mtu = Math.min(response.getMtuV4(), response.getMtuV6());
		// Never set an MTU below MIN_V6_MTU on a network that has IPv6.
		if (mtu < MIN_V6_MTU) {
		mtu = MIN_V6_MTU;
		}
		interfaceMtu = mtu;
		}
		// Allow 0.0.0.0 or :: as a gateway;
		// this indicates a point-to-point interface.
		linkProperties.addRoute(new RouteInfo(null, gateway, null,
		@@ -1615,7 +1639,7 @@ public class DataConnection extends StateMachine {
		// set interface MTU
		// this may clobber the setting read from the APN db, but that's ok
		// TODO: remove once LinkProperties#setMtu is deprecated
		linkProperties.setMtu(response.getMtu());
		linkProperties.setMtu(interfaceMtu);

		result = SetupResult.SUCCESS;
		} catch (UnknownHostException e) {