Unify behavior of various cases of "no underlying networks"

Before this change, VPNs having no underlying networks would be
marked as metered as the safe option, but VPNs having only
disconnected underlying networks would be marked as unmetered.
Fix this discrepancy.

Bug: 79748782
Test: runtest frameworks-net
Change-Id: I51c3badde29f43f692f383553bd98327d2da8dd1

2 files changed, 11 insertions, 10 deletions

diff --git a/services/core/java/com/android/server/connectivity/Vpn.java b/services/core/java/com/android/server/connectivity/Vpn.java
index dd82950fe020..a91989838521 100644
--- a/services/core/java/com/android/server/connectivity/Vpn.java
+++ b/services/core/java/com/android/server/connectivity/Vpn.java
@@ -319,15 +319,12 @@ public class Vpn {
         boolean roaming = false;
         boolean congested = false;
 
-        if (ArrayUtils.isEmpty(underlyingNetworks)) {
-            // No idea what the underlying networks are; assume sane defaults
-            metered = true;
-            roaming = false;
-            congested = false;
-        } else {
+        boolean hadUnderlyingNetworks = false;
+        if (null != underlyingNetworks) {
             for (Network underlying : underlyingNetworks) {
                 final NetworkCapabilities underlyingCaps = cm.getNetworkCapabilities(underlying);
                 if (underlyingCaps == null) continue;
+                hadUnderlyingNetworks = true;
                 for (int underlyingType : underlyingCaps.getTransportTypes()) {
                     transportTypes = ArrayUtils.appendInt(transportTypes, underlyingType);
                 }
@@ -343,6 +340,12 @@ public class Vpn {
                 congested |= !underlyingCaps.hasCapability(NET_CAPABILITY_NOT_CONGESTED);
             }
         }
+        if (!hadUnderlyingNetworks) {
+            // No idea what the underlying networks are; assume sane defaults
+            metered = true;
+            roaming = false;
+            congested = false;
+        }
 
         caps.setTransportTypes(transportTypes);
         caps.setLinkDownstreamBandwidthKbps(downKbps);
diff --git a/tests/net/java/com/android/server/ConnectivityServiceTest.java b/tests/net/java/com/android/server/ConnectivityServiceTest.java
index cf7ab4294b98..220858081e93 100644
--- a/tests/net/java/com/android/server/ConnectivityServiceTest.java
+++ b/tests/net/java/com/android/server/ConnectivityServiceTest.java
@@ -4413,13 +4413,11 @@ public class ConnectivityServiceTest {
                 && caps.hasCapability(NET_CAPABILITY_NOT_METERED),
                 vpnNetworkAgent);
 
-        // Disconnect wifi too. No underlying networks should mean this is now metered,
-        // unfortunately a discrepancy in the current implementation has this unmetered.
-        // TODO : fix this.
+        // Disconnect wifi too. No underlying networks means this is now metered.
         mWiFiNetworkAgent.disconnect();
         vpnNetworkCallback.expectCapabilitiesLike((caps) -> caps.hasTransport(TRANSPORT_VPN)
                 && !caps.hasTransport(TRANSPORT_CELLULAR) && !caps.hasTransport(TRANSPORT_WIFI)
-                && caps.hasCapability(NET_CAPABILITY_NOT_METERED),
+                && !caps.hasCapability(NET_CAPABILITY_NOT_METERED),
                 vpnNetworkAgent);
 
         mMockVpn.disconnect();