Merge "[NS04] Introduce Network Offers and their callbacks" am: daffcf97ef (f3249af8) · Commits · e / os / android_frameworks_base

packages/Connectivity/framework/src/android/net/ConnectivityManager.java

+53 −0

Original line number	Diff line number	Diff line
		@@ -3337,7 +3337,60 @@ public class ConnectivityManager {
		provider.setProviderId(NetworkProvider.ID_NONE);
		}

		/**
		* Register or update a network offer with ConnectivityService.
		*
		* ConnectivityService keeps track of offers made by the various providers and matches
		* them to networking requests made by apps or the system. The provider supplies a score
		* and the capabilities of the network it might be able to bring up ; these act as filters
		* used by ConnectivityService to only send those requests that can be fulfilled by the
		* provider.
		*
		* The provider is under no obligation to be able to bring up the network it offers at any
		* given time. Instead, this mechanism is meant to limit requests received by providers
		* to those they actually have a chance to fulfill, as providers don't have a way to compare
		* the quality of the network satisfying a given request to their own offer.
		*
		* An offer can be updated by calling this again with the same callback object. This is
		* similar to calling unofferNetwork and offerNetwork again, but will only update the
		* provider with the changes caused by the changes in the offer.
		*
		* @param provider The provider making this offer.
		* @param score The prospective score of the network.
		* @param caps The prospective capabilities of the network.
		* @param callback The callback to call when this offer is needed or unneeded.
		* @hide
		*/
		@RequiresPermission(anyOf = {
		NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK,
		android.Manifest.permission.NETWORK_FACTORY})
		public void offerNetwork(@NonNull final NetworkProvider provider,
		@NonNull final NetworkScore score, @NonNull final NetworkCapabilities caps,
		@NonNull final INetworkOfferCallback callback) {
		try {
		mService.offerNetwork(Objects.requireNonNull(provider.getMessenger(), "null messenger"),
		Objects.requireNonNull(score, "null score"),
		Objects.requireNonNull(caps, "null caps"),
		Objects.requireNonNull(callback, "null callback"));
		} catch (RemoteException e) {
		throw e.rethrowFromSystemServer();
		}
		}

		/**
		* Withdraw a network offer made with {@link #offerNetwork}.
		*
		* @param callback The callback passed at registration time. This must be the same object
		* that was passed to {@link #offerNetwork}
		* @hide
		*/
		public void unofferNetwork(@NonNull final INetworkOfferCallback callback) {
		try {
		mService.unofferNetwork(Objects.requireNonNull(callback));
		} catch (RemoteException e) {
		throw e.rethrowFromSystemServer();
		}
		}
		/** @hide exposed via the NetworkProvider class. */
		@RequiresPermission(anyOf = {
		NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK,

packages/Connectivity/framework/src/android/net/IConnectivityManager.aidl

+5 −0

Original line number	Diff line number	Diff line
		@@ -23,6 +23,7 @@ import android.net.IConnectivityDiagnosticsCallback;
		import android.net.INetworkAgent;
		import android.net.IOnCompleteListener;
		import android.net.INetworkActivityListener;
		import android.net.INetworkOfferCallback;
		import android.net.IQosCallback;
		import android.net.ISocketKeepaliveCallback;
		import android.net.LinkProperties;
		@@ -221,4 +222,8 @@ interface IConnectivityManager
		in IOnCompleteListener listener);

		int getRestrictBackgroundStatusByCaller();

		void offerNetwork(in Messenger messenger, in NetworkScore score,
		in NetworkCapabilities caps, in INetworkOfferCallback callback);
		void unofferNetwork(in INetworkOfferCallback callback);
		}

packages/Connectivity/framework/src/android/net/INetworkOfferCallback.aidl

0 → 100644

+62 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2021 The Android Open Source Project
		*
		* Licensed under the Apache License, Version 2.0 (the "License");
		* you may not use this file except in compliance with the License.
		* You may obtain a copy of the License at
		*
		* http://www.apache.org/licenses/LICENSE-2.0
		*
		* Unless required by applicable law or agreed to in writing, software
		* distributed under the License is distributed on an "AS IS" BASIS,
		* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
		* See the License for the specific language governing permissions and
		* limitations under the License.
		*/

		package android.net;

		import android.net.NetworkRequest;

		/**
		* A callback registered with connectivity by network providers together with
		* a NetworkOffer.
		*
		* When the offer is needed to satisfy some application or system component,
		* connectivity will call onOfferNeeded on this callback. When this happens,
		* the provider should try and bring up the network.
		*
		* When the offer is no longer needed, for example because the application has
		* withdrawn the request or if the request is being satisfied by a network
		* that this offer will never be able to beat, connectivity calls
		* onOfferUnneeded. When this happens, the provider should stop trying to
		* bring up the network, or tear it down if it has already been brought up.
		*
		* When NetworkProvider#offerNetwork is called, the provider can expect to
		* immediately receive all requests that can be fulfilled by that offer and
		* are not already satisfied by a better network. It is possible no such
		* request is currently outstanding, because no requests have been made that
		* can be satisfied by this offer, or because all such requests are already
		* satisfied by a better network.
		* onOfferNeeded can be called at any time after registration and until the
		* offer is withdrawn with NetworkProvider#unofferNetwork is called. This
		* typically happens when a new network request is filed by an application,
		* or when the network satisfying a request disconnects and this offer now
		* stands a chance to be the best network for it.
		*
		* @hide
		*/
		oneway interface INetworkOfferCallback {
		/**
		* Informs the registrant that the offer is needed to fulfill this request.
		* @param networkRequest the request to satisfy
		* @param providerId the ID of the provider currently satisfying
		* this request, or NetworkProvider.ID_NONE if none.
		*/
		void onOfferNeeded(in NetworkRequest networkRequest, int providerId);

		/**
		* Informs the registrant that the offer is no longer needed to fulfill this request.
		*/
		void onOfferUnneeded(in NetworkRequest networkRequest);
		}

packages/Connectivity/framework/src/android/net/NetworkProvider.java

+152 −1

Original line number	Diff line number	Diff line
		@@ -28,6 +28,11 @@ import android.os.Message;
		import android.os.Messenger;
		import android.util.Log;

		import com.android.internal.annotations.GuardedBy;

		import java.util.ArrayList;
		import java.util.concurrent.Executor;

		/**
		* Base class for network providers such as telephony or Wi-Fi. NetworkProviders connect the device
		* to networks and makes them available to the core network stack by creating
		@@ -78,7 +83,9 @@ public class NetworkProvider {
		*/
		@SystemApi
		public NetworkProvider(@NonNull Context context, @NonNull Looper looper, @NonNull String name) {
		Handler handler = new Handler(looper) {
		// TODO (b/174636568) : this class should be able to cache an instance of
		// ConnectivityManager so it doesn't have to fetch it again every time.
		final Handler handler = new Handler(looper) {
		@Override
		public void handleMessage(Message m) {
		switch (m.what) {
		@@ -159,4 +166,148 @@ public class NetworkProvider {
		public void declareNetworkRequestUnfulfillable(@NonNull NetworkRequest request) {
		ConnectivityManager.from(mContext).declareNetworkRequestUnfulfillable(request);
		}

		/** @hide */
		// TODO : make @SystemApi when the impl is complete
		public interface NetworkOfferCallback {
		/** Called by the system when this offer is needed to satisfy some networking request. */
		void onOfferNeeded(@NonNull NetworkRequest request, int providerId);
		/** Called by the system when this offer is no longer needed. */
		void onOfferUnneeded(@NonNull NetworkRequest request);
		}

		private class NetworkOfferCallbackProxy extends INetworkOfferCallback.Stub {
		@NonNull public final NetworkOfferCallback callback;
		@NonNull private final Executor mExecutor;

		NetworkOfferCallbackProxy(@NonNull final NetworkOfferCallback callback,
		@NonNull final Executor executor) {
		this.callback = callback;
		this.mExecutor = executor;
		}

		@Override
		public void onOfferNeeded(final @NonNull NetworkRequest request,
		final int providerId) {
		mExecutor.execute(() -> callback.onOfferNeeded(request, providerId));
		}

		@Override
		public void onOfferUnneeded(final @NonNull NetworkRequest request) {
		mExecutor.execute(() -> callback.onOfferUnneeded(request));
		}
		}

		@GuardedBy("mProxies")
		@NonNull private final ArrayList<NetworkOfferCallbackProxy> mProxies = new ArrayList<>();

		// Returns the proxy associated with this callback, or null if none.
		@Nullable
		private NetworkOfferCallbackProxy findProxyForCallback(@NonNull final NetworkOfferCallback cb) {
		synchronized (mProxies) {
		for (final NetworkOfferCallbackProxy p : mProxies) {
		if (p.callback == cb) return p;
		}
		}
		return null;
		}

		/**
		* Register or update an offer for network with the passed caps and score.
		*
		* A NetworkProvider's job is to provide networks. This function is how a provider tells the
		* connectivity stack what kind of network it may provide. The score and caps arguments act
		* as filters that the connectivity stack uses to tell when the offer is necessary. When an
		* offer might be advantageous over existing networks, the provider will receive a call to
		* the associated callback's {@link NetworkOfferCallback#onOfferNeeded} method. The provider
		* should then try to bring up this network. When an offer is no longer needed, the stack
		* will inform the provider by calling {@link NetworkOfferCallback#onOfferUnneeded}. The
		* provider should stop trying to bring up such a network, or disconnect it if it already has
		* one.
		*
		* The stack determines what offers are needed according to what networks are currently
		* available to the system, and what networking requests are made by applications. If an
		* offer looks like it could be a better choice than any existing network for any particular
		* request, that's when the stack decides the offer is needed. If the current networking
		* requests are all satisfied by networks that this offer can't possibly be a better match
		* for, that's when the offer is unneeded. An offer starts off as unneeded ; the provider
		* should not try to bring up the network until {@link NetworkOfferCallback#onOfferNeeded}
		* is called.
		*
		* Note that the offers are non-binding to the providers, in particular because providers
		* often don't know if they will be able to bring up such a network at any given time. For
		* example, no wireless network may be in range when the offer is needed. This is fine and
		* expected ; the provider should simply continue to try to bring up the network and do so
		* if/when it becomes possible. In the mean time, the stack will continue to satisfy requests
		* with the best network currently available, or if none, keep the apps informed that no
		* network can currently satisfy this request. When/if the provider can bring up the network,
		* the connectivity stack will match it against requests, and inform interested apps of the
		* availability of this network. This may, in turn, render the offer of some other provider
		* unneeded if all requests it used to satisfy are now better served by this network.
		*
		* A network can become unneeded for a reason like the above : whether the provider managed
		* to bring up the offered network after it became needed or not, some other provider may
		* bring up a better network than this one, making this offer unneeded. A network may also
		* become unneeded if the application making the request withdrew it (for example, after it
		* is done transferring data, or if the user canceled an operation).
		*
		* The capabilities and score act as filters as to what requests the provider will see.
		* They are not promises, but for best performance, the providers should strive to put
		* as much known information as possible in the offer. For capabilities in particular, it
		* should put all NetworkAgent-managed capabilities a network may have, even if it doesn't
		* have them at first. This applies to INTERNET, for example ; if a provider thinks the
		* network it can bring up for this offer may offer Internet access it should include the
		* INTERNET bit. It's fine if the brought up network ends up not actually having INTERNET.
		*
		* TODO : in the future, to avoid possible infinite loops, there should be constraints on
		* what can be put in capabilities of networks brought up for an offer. If a provider might
		* bring up a network with or without INTERNET, then it should file two offers : this will
		* let it know precisely what networks are needed, so it can avoid bringing up networks that
		* won't actually satisfy requests and remove the risk for bring-up-bring-down loops.
		*
		* @hide
		*/
		// TODO : make @SystemApi when the impl is complete
		@RequiresPermission(android.Manifest.permission.NETWORK_FACTORY)
		public void offerNetwork(@NonNull final NetworkScore score,
		@NonNull final NetworkCapabilities caps, @NonNull final Executor executor,
		@NonNull final NetworkOfferCallback callback) {
		NetworkOfferCallbackProxy proxy = null;
		synchronized (mProxies) {
		for (final NetworkOfferCallbackProxy existingProxy : mProxies) {
		if (existingProxy.callback == callback) {
		proxy = existingProxy;
		break;
		}
		}
		if (null == proxy) {
		proxy = new NetworkOfferCallbackProxy(callback, executor);
		mProxies.add(proxy);
		}
		}
		mContext.getSystemService(ConnectivityManager.class).offerNetwork(this, score, caps, proxy);
		}

		/**
		* Withdraw a network offer previously made to the networking stack.
		*
		* If a provider can no longer provide a network they offered, it should call this method.
		* An example of usage could be if the hardware necessary to bring up the network was turned
		* off in UI by the user. Note that because offers are never binding, the provider might
		* alternatively decide not to withdraw this offer and simply refuse to bring up the network
		* even when it's needed. However, withdrawing the request is slightly more resource-efficient
		* because the networking stack won't have to compare this offer to exiting networks to see
		* if it could beat any of them, and may be advantageous to the provider's implementation that
		* can rely on no longer receiving callbacks for a network that they can't bring up anyways.
		*
		* @hide
		*/
		// TODO : make @SystemApi when the impl is complete
		@RequiresPermission(android.Manifest.permission.NETWORK_FACTORY)
		public void unofferNetwork(final @NonNull NetworkOfferCallback callback) {
		final NetworkOfferCallbackProxy proxy = findProxyForCallback(callback);
		if (null == proxy) return;
		mProxies.remove(proxy);
		mContext.getSystemService(ConnectivityManager.class).unofferNetwork(proxy);
		}
		}

services/core/Android.bp

+1 −0

Original line number	Diff line number	Diff line
		@@ -218,6 +218,7 @@ filegroup {
		"java/com/android/server/connectivity/NetworkAgentInfo.java",
		"java/com/android/server/connectivity/NetworkDiagnostics.java",
		"java/com/android/server/connectivity/NetworkNotificationManager.java",
		"java/com/android/server/connectivity/NetworkOffer.java",
		"java/com/android/server/connectivity/NetworkRanker.java",
		"java/com/android/server/connectivity/PermissionMonitor.java",
		"java/com/android/server/connectivity/ProxyTracker.java",