commit 69e1aa9117adeaf07e3c1d5612e466b4a6ae7ff5
author lucaslin <lucaslin@google.com> Tue Mar 22 18:15:09 2022 +0800
committer lucaslin <lucaslin@google.com> Tue Mar 22 18:15:09 2022 +0800
tree fa075a85f4bcb58265fe268b81664f297982dc0c
parent f7c071b1c4172e66e396972cdab26b0cc744b620

Add @RequiresPermission for setUnderlyingNetworks

setUnderlyingNetworks() is mainly for the NetworkAgents who hold
the NETWORK_FACTORY to set its underlying networks.

And the underlying networks are only visible and useful for the
caller of getNetworkCapabilities() or the receiver of
onCapabilitiesChanged() who hold one of NETWORK_FACTORY,
NETWORK_SETTINGS and MAINLINE_NETWORK_STACK permissions.
Otherwise, the underlying networks field will be cleard before
sending.

Bug: 205738644
Test: atest CtsNetTestCases:ConnectivityManagerTest
      atest CtsHostsideNetworkTests:HostsideVpnTests
      atest FrameworksNetTests
Change-Id: Ife7630d9676a31ee5ab977cb1b87aec3b6fd7080

service/src/com/android/server/ConnectivityService.java

diff --git a/service/src/com/android/server/ConnectivityService.java b/service/src/com/android/server/ConnectivityService.java
index e58160a..32d306a 100644
--- a/service/src/com/android/server/ConnectivityService.java
+++ b/service/src/com/android/server/ConnectivityService.java
@@ -2235,6 +2235,13 @@
                 callingAttributionTag);
     }
 
+    private void redactUnderlyingNetworksForCapabilities(NetworkCapabilities nc, int pid, int uid) {
+        if (nc.getUnderlyingNetworks() != null
+                && !checkNetworkFactoryOrSettingsPermission(pid, uid)) {
+            nc.setUnderlyingNetworks(null);
+        }
+    }
+
     @VisibleForTesting
     NetworkCapabilities networkCapabilitiesRestrictedForCallerPermissions(
             NetworkCapabilities nc, int callerPid, int callerUid) {
@@ -2247,8 +2254,6 @@
         if (!checkSettingsPermission(callerPid, callerUid)) {
             newNc.setUids(null);
             newNc.setSSID(null);
-            // TODO: Processes holding NETWORK_FACTORY should be able to see the underlying networks
-            newNc.setUnderlyingNetworks(null);
         }
         if (newNc.getNetworkSpecifier() != null) {
             newNc.setNetworkSpecifier(newNc.getNetworkSpecifier().redact());
@@ -2262,6 +2267,7 @@
             newNc.setAllowedUids(new ArraySet<>());
             newNc.setSubscriptionIds(Collections.emptySet());
         }
+        redactUnderlyingNetworksForCapabilities(newNc, callerPid, callerUid);
 
         return newNc;
     }
@@ -2874,6 +2880,15 @@
                 NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK);
     }
 
+    private boolean checkNetworkFactoryOrSettingsPermission(int pid, int uid) {
+        return PERMISSION_GRANTED == mContext.checkPermission(
+                android.Manifest.permission.NETWORK_FACTORY, pid, uid)
+                || PERMISSION_GRANTED == mContext.checkPermission(
+                android.Manifest.permission.NETWORK_SETTINGS, pid, uid)
+                || PERMISSION_GRANTED == mContext.checkPermission(
+                NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK, pid, uid);
+    }
+
     private boolean checkSettingsPermission() {
         return checkAnyPermissionOf(
                 android.Manifest.permission.NETWORK_SETTINGS,