From d4c4a2c95b605c17b184e2c69a395a3d2303d50e Mon Sep 17 00:00:00 2001
From: lucaslin <lucaslin@google.com>
Date: Wed, 23 Jun 2021 08:17:55 +0800
Subject: [PATCH] Throw UnsupportedOperationException if startLegacyVpn is
 called

Legacy VPN is deprecated starting from Android S. So this API
shouldn't be called if the initial SDK version of device is
Android S+. Otherwise, UnsupportedOperationException will be
thrown.

Bug: 189808606
Test: 1. make gts && gts-tradefed
      2. run gts --module GtsNetworkStackHostTestCases
Change-Id: I00f49555bbbc8ccf270056f0e4d1bfdd927ef26d
---
 core/java/android/net/VpnManager.java                    | 4 ++++
 .../core/java/com/android/server/VpnManagerService.java  | 9 +++++++++
 2 files changed, 13 insertions(+)

diff --git a/core/java/android/net/VpnManager.java b/core/java/android/net/VpnManager.java
index 662ebb356f4c4..5c2855307509c 100644
--- a/core/java/android/net/VpnManager.java
+++ b/core/java/android/net/VpnManager.java
@@ -389,6 +389,10 @@ public class VpnManager {
 
     /**
      * Starts a legacy VPN.
+     *
+     * Legacy VPN is deprecated starting from Android S. So this API shouldn't be called if the
+     * initial SDK version of device is Android S+. Otherwise, UnsupportedOperationException will be
+     * thrown.
      * @hide
      */
     public void startLegacyVpn(VpnProfile profile) {
diff --git a/services/core/java/com/android/server/VpnManagerService.java b/services/core/java/com/android/server/VpnManagerService.java
index 26ecee8f21aba..70176a0fefeb0 100644
--- a/services/core/java/com/android/server/VpnManagerService.java
+++ b/services/core/java/com/android/server/VpnManagerService.java
@@ -38,6 +38,7 @@ import android.net.VpnManager;
 import android.net.VpnService;
 import android.net.util.NetdService;
 import android.os.Binder;
+import android.os.Build;
 import android.os.Handler;
 import android.os.HandlerThread;
 import android.os.INetworkManagementService;
@@ -348,9 +349,17 @@ public class VpnManagerService extends IVpnManager.Stub {
     /**
      * Start legacy VPN, controlling native daemons as needed. Creates a
      * secondary thread to perform connection work, returning quickly.
+     *
+     * Legacy VPN is deprecated starting from Android S. So this API shouldn't be called if the
+     * initial SDK version of device is Android S+. Otherwise, UnsupportedOperationException will be
+     * thrown.
      */
+    @SuppressWarnings("AndroidFrameworkCompatChange")  // This is not an app-visible API.
     @Override
     public void startLegacyVpn(VpnProfile profile) {
+        if (Build.VERSION.DEVICE_INITIAL_SDK_INT >= Build.VERSION_CODES.S) {
+            throw new UnsupportedOperationException("Legacy VPN is deprecated");
+        }
         int user = UserHandle.getUserId(mDeps.getCallingUid());
         // Note that if the caller is not system (uid >= Process.FIRST_APPLICATION_UID),
         // the code might not work well since getActiveNetwork might return null if the uid is