Explicitly disallow multiple user execute

Explicitly disallow multiple user execution:
it's not expected because everything runs as system
but this change explicitly rules out execution.

This change also adds an xTS to confirm that
a secondary user installing the app triggers
an update (as the owner) and the device is updated
correctly.

Test: Manual testing installing updates as secondary device user
Test: PTS: run pts -m PtsTimeZoneTestCases
Bug: 64111659
Change-Id: Ic839bb264b9ce5448e6191c71ffb7c2b634e4efa

1 files changed, 9 insertions, 0 deletions

diff --git a/src/main/com/android/timezone/data/TimeZoneRulesDataProvider.java b/src/main/com/android/timezone/data/TimeZoneRulesDataProvider.java
index 194620f..d92665a 100644
--- a/src/main/com/android/timezone/data/TimeZoneRulesDataProvider.java
+++ b/src/main/com/android/timezone/data/TimeZoneRulesDataProvider.java
@@ -31,6 +31,7 @@ import android.database.Cursor;
 import android.net.Uri;
 import android.os.Bundle;
 import android.os.ParcelFileDescriptor;
+import android.os.UserHandle;
 import android.provider.TimeZoneRulesDataContract;
 import android.provider.TimeZoneRulesDataContract.Operation;
 import android.support.annotation.NonNull;
@@ -94,6 +95,14 @@ public final class TimeZoneRulesDataProvider extends ContentProvider {
     public void attachInfo(Context context, ProviderInfo info) {
         super.attachInfo(context, info);
 
+        // The time zone update process should run as the system user exclusively as it's a
+        // system feature, not user dependent.
+        UserHandle currentUserHandle = android.os.Process.myUserHandle();
+        if (!currentUserHandle.isSystem()) {
+            throw new SecurityException("ContentProvider is supposed to run as the system user,"
+                    + " instead user=" + currentUserHandle);
+        }
+
         // Sanity check our security
         if (!TimeZoneRulesDataContract.AUTHORITY.equals(info.authority)) {
             // The authority looked for by the time zone updater is fixed.