Add new callback to inform blocking of network on specific uid.

Currently, apps rely on querying NetworkInfo object to know
whether their network is blocked or not. There is no proactive
way to tell app when it is being blocked/unblocked. The only
event that app would receive is SocketException with
ECONNABORTED when their ongoing socket connection has been
blocked, which is not an elegant way to notify app.

Thus, this commit is trying to address this problem. Therefore,
with the uses of other callbacks, the need of
getState/getDetailedState in NetworkInfo could be completely
eliminated.

Test: runtest frameworks-net
      runtest -x NetworkPolicyManagerServiceTest.java
      cts-tradefed run cts -m CtsHostsideNetworkTests
      cts-tradefed run cts -m CtsNetTestCases -t \
              android.net.cts.ConnectivityManagerTest
Bug: 74575553

Change-Id: Iec96a3103d0aa9a505020eb89d69b89c0b694486

3 files changed, 51 insertions, 3 deletions

diff --git a/core/java/android/net/ConnectivityManager.java b/core/java/android/net/ConnectivityManager.java
index 8333b817add0..c610beed7602 100644
--- a/core/java/android/net/ConnectivityManager.java
+++ b/core/java/android/net/ConnectivityManager.java
@@ -2809,10 +2809,11 @@ public class ConnectivityManager {
          * @param network The {@link Network} of the satisfying network.
          * @param networkCapabilities The {@link NetworkCapabilities} of the satisfying network.
          * @param linkProperties The {@link LinkProperties} of the satisfying network.
+         * @param blocked Whether access to the {@link Network} is blocked due to system policy.
          * @hide
          */
         public void onAvailable(Network network, NetworkCapabilities networkCapabilities,
-                LinkProperties linkProperties) {
+                LinkProperties linkProperties, boolean blocked) {
             // Internally only this method is called when a new network is available, and
             // it calls the callback in the same way and order that older versions used
             // to call so as not to change the behavior.
@@ -2823,6 +2824,7 @@ public class ConnectivityManager {
             }
             onCapabilitiesChanged(network, networkCapabilities);
             onLinkPropertiesChanged(network, linkProperties);
+            onBlockedStatusChanged(network, blocked);
         }
 
         /**
@@ -2830,7 +2832,8 @@ public class ConnectivityManager {
          * This callback may be called more than once if the {@link Network} that is
          * satisfying the request changes. This will always immediately be followed by a
          * call to {@link #onCapabilitiesChanged(Network, NetworkCapabilities)} then by a
-         * call to {@link #onLinkPropertiesChanged(Network, LinkProperties)}.
+         * call to {@link #onLinkPropertiesChanged(Network, LinkProperties)}, and a call to
+         * {@link #onBlockedStatusChanged(Network, boolean)}.
          *
          * @param network The {@link Network} of the satisfying network.
          */
@@ -2909,6 +2912,14 @@ public class ConnectivityManager {
          */
         public void onNetworkResumed(Network network) {}
 
+        /**
+         * Called when access to the specified network is blocked or unblocked.
+         *
+         * @param network The {@link Network} whose blocked status has changed.
+         * @param blocked The blocked status of this {@link Network}.
+         */
+        public void onBlockedStatusChanged(Network network, boolean blocked) {}
+
         private NetworkRequest networkRequest;
     }
 
@@ -2955,6 +2966,8 @@ public class ConnectivityManager {
     public static final int CALLBACK_SUSPENDED           = BASE + 9;
     /** @hide */
     public static final int CALLBACK_RESUMED             = BASE + 10;
+    /** @hide */
+    public static final int CALLBACK_BLK_CHANGED         = BASE + 11;
 
     /** @hide */
     public static String getCallbackName(int whichCallback) {
@@ -2969,6 +2982,7 @@ public class ConnectivityManager {
             case EXPIRE_LEGACY_REQUEST: return "EXPIRE_LEGACY_REQUEST";
             case CALLBACK_SUSPENDED:    return "CALLBACK_SUSPENDED";
             case CALLBACK_RESUMED:      return "CALLBACK_RESUMED";
+            case CALLBACK_BLK_CHANGED:  return "CALLBACK_BLK_CHANGED";
             default:
                 return Integer.toString(whichCallback);
         }
@@ -3015,7 +3029,7 @@ public class ConnectivityManager {
                 case CALLBACK_AVAILABLE: {
                     NetworkCapabilities cap = getObject(message, NetworkCapabilities.class);
                     LinkProperties lp = getObject(message, LinkProperties.class);
-                    callback.onAvailable(network, cap, lp);
+                    callback.onAvailable(network, cap, lp, message.arg1 != 0);
                     break;
                 }
                 case CALLBACK_LOSING: {
@@ -3048,6 +3062,10 @@ public class ConnectivityManager {
                     callback.onNetworkResumed(network);
                     break;
                 }
+                case CALLBACK_BLK_CHANGED: {
+                    boolean blocked = message.arg1 != 0;
+                    callback.onBlockedStatusChanged(network, blocked);
+                }
             }
         }
 
diff --git a/core/java/android/net/NetworkCapabilities.java b/core/java/android/net/NetworkCapabilities.java
index fd1e5f23382b..74cd1433f574 100644
--- a/core/java/android/net/NetworkCapabilities.java
+++ b/core/java/android/net/NetworkCapabilities.java
@@ -1589,4 +1589,14 @@ public final class NetworkCapabilities implements Parcelable {
         Preconditions.checkArgument(isValidCapability(capability),
                 "NetworkCapability " + capability + "out of range");
     }
+
+    /**
+     * Check if this {@code NetworkCapability} instance is metered.
+     *
+     * @return {@code true} if {@code NET_CAPABILITY_NOT_METERED} is not set on this instance.
+     * @hide
+     */
+    public boolean isMetered() {
+        return !hasCapability(NET_CAPABILITY_NOT_METERED);
+    }
 }
diff --git a/core/java/android/net/NetworkInfo.java b/core/java/android/net/NetworkInfo.java
index d912dd105fe9..1a1d2d33424c 100644
--- a/core/java/android/net/NetworkInfo.java
+++ b/core/java/android/net/NetworkInfo.java
@@ -202,7 +202,9 @@ public class NetworkInfo implements Parcelable {
      * Return a network-type-specific integer describing the subtype
      * of the network.
      * @return the network subtype
+     * @deprecated Use {@link android.telephony.TelephonyManager#getDataNetworkType} instead.
      */
+    @Deprecated
     public int getSubtype() {
         synchronized (this) {
             return mSubtype;
@@ -243,7 +245,9 @@ public class NetworkInfo implements Parcelable {
     /**
      * Return a human-readable name describing the subtype of the network.
      * @return the name of the network subtype
+     * @deprecated Use {@link android.telephony.TelephonyManager#getDataNetworkType} instead.
      */
+    @Deprecated
     public String getSubtypeName() {
         synchronized (this) {
             return mSubtypeName;
@@ -278,7 +282,15 @@ public class NetworkInfo implements Parcelable {
      * connections and pass data.
      * <p>Always call this before attempting to perform data transactions.
      * @return {@code true} if network connectivity exists, {@code false} otherwise.
+     * @deprecated Apps should instead use the
+     *             {@link android.net.ConnectivityManager.NetworkCallback} API to
+     *             learn about connectivity changes. See
+     *             {@link ConnectivityManager#registerDefaultNetworkCallback} and
+     *             {@link ConnectivityManager#registerNetworkCallback}. These will
+     *             give a more accurate picture of the connectivity state of
+     *             the device and let apps react more easily and quickly to changes.
      */
+    @Deprecated
     public boolean isConnected() {
         synchronized (this) {
             return mState == State.CONNECTED;
@@ -411,7 +423,15 @@ public class NetworkInfo implements Parcelable {
     /**
      * Reports the current fine-grained state of the network.
      * @return the fine-grained state
+     * @deprecated Apps should instead use the
+     *             {@link android.net.ConnectivityManager.NetworkCallback} API to
+     *             learn about connectivity changes. See
+     *             {@link ConnectivityManager#registerDefaultNetworkCallback} and
+     *             {@link ConnectivityManager#registerNetworkCallback}. These will
+     *             give a more accurate picture of the connectivity state of
+     *             the device and let apps react more easily and quickly to changes.
      */
+    @Deprecated
     public DetailedState getDetailedState() {
         synchronized (this) {
             return mDetailedState;