Allow system components to request underlying network policies.

This CL updates VcnManager to allow system components with permission
NETWORK_FACTORY to request the current VcnUnderlingNetworkPolicy for a
specific Network's NetworkCapabilities and LinkProperties.

Bug: 175900686
Test: atest FrameworksVcnTests
Change-Id: I16416e619bdb03630582f5660260b0090730e9eb

2 files changed, 38 insertions, 1 deletions

diff --git a/core/java/android/net/vcn/IVcnManagementService.aidl b/core/java/android/net/vcn/IVcnManagementService.aidl
index 80ac64b87d4d..4f293eeb3c3b 100644
--- a/core/java/android/net/vcn/IVcnManagementService.aidl
+++ b/core/java/android/net/vcn/IVcnManagementService.aidl
@@ -16,8 +16,11 @@
 
 package android.net.vcn;
 
+import android.net.LinkProperties;
+import android.net.NetworkCapabilities;
 import android.net.vcn.IVcnUnderlyingNetworkPolicyListener;
 import android.net.vcn.VcnConfig;
+import android.net.vcn.VcnUnderlyingNetworkPolicy;
 import android.os.ParcelUuid;
 
 /**
@@ -29,4 +32,5 @@ interface IVcnManagementService {
 
     void addVcnUnderlyingNetworkPolicyListener(in IVcnUnderlyingNetworkPolicyListener listener);
     void removeVcnUnderlyingNetworkPolicyListener(in IVcnUnderlyingNetworkPolicyListener listener);
+    VcnUnderlyingNetworkPolicy getUnderlyingNetworkPolicy(in NetworkCapabilities nc, in LinkProperties lp);
 }
diff --git a/core/java/android/net/vcn/VcnManager.java b/core/java/android/net/vcn/VcnManager.java
index 2d0a6d74cb86..33beb6a9d188 100644
--- a/core/java/android/net/vcn/VcnManager.java
+++ b/core/java/android/net/vcn/VcnManager.java
@@ -21,6 +21,8 @@ import android.annotation.NonNull;
 import android.annotation.RequiresPermission;
 import android.annotation.SystemService;
 import android.content.Context;
+import android.net.LinkProperties;
+import android.net.NetworkCapabilities;
 import android.os.ParcelUuid;
 import android.os.RemoteException;
 import android.os.ServiceSpecificException;
@@ -62,7 +64,7 @@ import java.util.concurrent.Executor;
  * @hide
  */
 @SystemService(Context.VCN_MANAGEMENT_SERVICE)
-public final class VcnManager {
+public class VcnManager {
     @NonNull private static final String TAG = VcnManager.class.getSimpleName();
 
     /** @hide */
@@ -223,6 +225,37 @@ public final class VcnManager {
     }
 
     /**
+     * Queries the underlying network policy for a network with the given parameters.
+     *
+     * <p>Prior to a new NetworkAgent being registered, or upon notification that Carrier VCN policy
+     * may have changed via {@link VcnUnderlyingNetworkPolicyListener#onPolicyChanged()}, a Network
+     * Provider MUST poll for the updated Network policy based on that Network's capabilities and
+     * properties.
+     *
+     * @param networkCapabilities the NetworkCapabilities to be used in determining the Network
+     *     policy for this Network.
+     * @param linkProperties the LinkProperties to be used in determining the Network policy for
+     *     this Network.
+     * @throws SecurityException if the caller does not have permission NETWORK_FACTORY
+     * @return the VcnUnderlyingNetworkPolicy to be used for this Network.
+     * @hide
+     */
+    @NonNull
+    @RequiresPermission(android.Manifest.permission.NETWORK_FACTORY)
+    public VcnUnderlyingNetworkPolicy getUnderlyingNetworkPolicy(
+            @NonNull NetworkCapabilities networkCapabilities,
+            @NonNull LinkProperties linkProperties) {
+        requireNonNull(networkCapabilities, "networkCapabilities must not be null");
+        requireNonNull(linkProperties, "linkProperties must not be null");
+
+        try {
+            return mService.getUnderlyingNetworkPolicy(networkCapabilities, linkProperties);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
+    /**
      * Binder wrapper for added VcnUnderlyingNetworkPolicyListeners to receive signals from System
      * Server.
      *