Better network stats parsing, integer tags, async.

Change NMS parsing to handle extended /proc/ stats formats by pairing
values with header keys.  Move TrafficStats to integer tags to match
kernel internals, and offer well-known tags for system services.

Async policy event dispatch from NPMS, and update tests to block for
event dispatch.  Narrow app policy to exclude apps signed with system
key, which are usually critical.

Bug: 4948913, 4903489, 4585280

Change-Id: Idb357227ccaa617906411f309371cea18d7bc519

1 files changed, 48 insertions, 58 deletions

diff --git a/services/java/com/android/server/net/NetworkPolicyManagerService.java b/services/java/com/android/server/net/NetworkPolicyManagerService.java
index 584cd03..12d3ed8 100644
--- a/services/java/com/android/server/net/NetworkPolicyManagerService.java
+++ b/services/java/com/android/server/net/NetworkPolicyManagerService.java
@@ -72,6 +72,7 @@ import android.os.Environment;
 import android.os.Handler;
 import android.os.HandlerThread;
 import android.os.IPowerManager;
+import android.os.Message;
 import android.os.RemoteCallbackList;
 import android.os.RemoteException;
 import android.telephony.TelephonyManager;
@@ -148,6 +149,9 @@ public class NetworkPolicyManagerService extends INetworkPolicyManager.Stub {
 
     private static final long TIME_CACHE_MAX_AGE = DAY_IN_MILLIS;
 
+    private static final int MSG_RULES_CHANGED = 0x1;
+    private static final int MSG_METERED_IFACES_CHANGED = 0x2;
+
     private final Context mContext;
     private final IActivityManager mActivityManager;
     private final IPowerManager mPowerManager;
@@ -210,7 +214,7 @@ public class NetworkPolicyManagerService extends INetworkPolicyManager.Stub {
 
         mHandlerThread = new HandlerThread(TAG);
         mHandlerThread.start();
-        mHandler = new Handler(mHandlerThread.getLooper());
+        mHandler = new Handler(mHandlerThread.getLooper(), mHandlerCallback);
 
         mPolicyFile = new AtomicFile(new File(systemDir, "netpolicy.xml"));
     }
@@ -269,9 +273,6 @@ public class NetworkPolicyManagerService extends INetworkPolicyManager.Stub {
             // only someone like AMS should only be calling us
             mContext.enforceCallingOrSelfPermission(MANAGE_APP_TOKENS, TAG);
 
-            // skip when UID couldn't have any policy
-            if (!isUidValidForPolicy(mContext, uid)) return;
-
             synchronized (mRulesLock) {
                 // because a uid can have multiple pids running inside, we need to
                 // remember all pid states and summarize foreground at uid level.
@@ -292,9 +293,6 @@ public class NetworkPolicyManagerService extends INetworkPolicyManager.Stub {
             // only someone like AMS should only be calling us
             mContext.enforceCallingOrSelfPermission(MANAGE_APP_TOKENS, TAG);
 
-            // skip when UID couldn't have any policy
-            if (!isUidValidForPolicy(mContext, uid)) return;
-
             synchronized (mRulesLock) {
                 // clear records and recompute, when they exist
                 final SparseBooleanArray pidForeground = mUidPidForeground.get(uid);
@@ -599,20 +597,8 @@ public class NetworkPolicyManagerService extends INetworkPolicyManager.Stub {
             }
         }
 
-        // dispatch changed rule to existing listeners
-        // TODO: dispatch outside of holding lock
         final String[] meteredIfaces = mMeteredIfaces.toArray(new String[mMeteredIfaces.size()]);
-        final int length = mListeners.beginBroadcast();
-        for (int i = 0; i < length; i++) {
-            final INetworkPolicyListener listener = mListeners.getBroadcastItem(i);
-            if (listener != null) {
-                try {
-                    listener.onMeteredIfacesChanged(meteredIfaces);
-                } catch (RemoteException e) {
-                }
-            }
-        }
-        mListeners.finishBroadcast();
+        mHandler.obtainMessage(MSG_METERED_IFACES_CHANGED, meteredIfaces).sendToTarget();
     }
 
     /**
@@ -804,32 +790,7 @@ public class NetworkPolicyManagerService extends INetworkPolicyManager.Stub {
 
         mListeners.register(listener);
 
-        synchronized (mRulesLock) {
-            // dispatch any existing rules to new listeners
-            // TODO: dispatch outside of holding lock
-            final int size = mUidRules.size();
-            for (int i = 0; i < size; i++) {
-                final int uid = mUidRules.keyAt(i);
-                final int uidRules = mUidRules.valueAt(i);
-                if (uidRules != RULE_ALLOW_ALL) {
-                    try {
-                        listener.onUidRulesChanged(uid, uidRules);
-                    } catch (RemoteException e) {
-                    }
-                }
-            }
-
-            // dispatch any metered ifaces to new listeners
-            // TODO: dispatch outside of holding lock
-            if (mMeteredIfaces.size() > 0) {
-                final String[] meteredIfaces = mMeteredIfaces.toArray(
-                        new String[mMeteredIfaces.size()]);
-                try {
-                    listener.onMeteredIfacesChanged(meteredIfaces);
-                } catch (RemoteException e) {
-                }
-            }
-        }
+        // TODO: consider dispatching existing rules to new listeners
     }
 
     @Override
@@ -978,8 +939,6 @@ public class NetworkPolicyManagerService extends INetworkPolicyManager.Stub {
     }
 
     private void updateRulesForUidLocked(int uid) {
-        if (!isUidValidForPolicy(mContext, uid)) return;
-
         final int uidPolicy = getUidPolicy(uid);
         final boolean uidForeground = isUidForeground(uid);
 
@@ -999,19 +958,50 @@ public class NetworkPolicyManagerService extends INetworkPolicyManager.Stub {
         //kernelSetUidRejectPaid(uid, rejectPaid);
 
         // dispatch changed rule to existing listeners
-        // TODO: dispatch outside of holding lock
-        final int length = mListeners.beginBroadcast();
-        for (int i = 0; i < length; i++) {
-            final INetworkPolicyListener listener = mListeners.getBroadcastItem(i);
-            if (listener != null) {
-                try {
-                    listener.onUidRulesChanged(uid, uidRules);
-                } catch (RemoteException e) {
+        mHandler.obtainMessage(MSG_RULES_CHANGED, uid, uidRules).sendToTarget();
+    }
+
+    private Handler.Callback mHandlerCallback = new Handler.Callback() {
+        /** {@inheritDoc} */
+        public boolean handleMessage(Message msg) {
+            switch (msg.what) {
+                case MSG_RULES_CHANGED: {
+                    final int uid = msg.arg1;
+                    final int uidRules = msg.arg2;
+                    final int length = mListeners.beginBroadcast();
+                    for (int i = 0; i < length; i++) {
+                        final INetworkPolicyListener listener = mListeners.getBroadcastItem(i);
+                        if (listener != null) {
+                            try {
+                                listener.onUidRulesChanged(uid, uidRules);
+                            } catch (RemoteException e) {
+                            }
+                        }
+                    }
+                    mListeners.finishBroadcast();
+                    return true;
+                }
+                case MSG_METERED_IFACES_CHANGED: {
+                    final String[] meteredIfaces = (String[]) msg.obj;
+                    final int length = mListeners.beginBroadcast();
+                    for (int i = 0; i < length; i++) {
+                        final INetworkPolicyListener listener = mListeners.getBroadcastItem(i);
+                        if (listener != null) {
+                            try {
+                                listener.onMeteredIfacesChanged(meteredIfaces);
+                            } catch (RemoteException e) {
+                            }
+                        }
+                    }
+                    mListeners.finishBroadcast();
+                    return true;
+                }
+                default: {
+                    return false;
                 }
             }
         }
-        mListeners.finishBroadcast();
-    }
+    };
 
     private String getActiveSubscriberId() {
         final TelephonyManager telephony = (TelephonyManager) mContext.getSystemService(