From 6e81f2a7dcbd5d98b07db944812ae084c025a49a Mon Sep 17 00:00:00 2001
From: nuccachen <nuccachen@google.com>
Date: Mon, 30 Jul 2018 17:29:45 +0800
Subject: [PATCH] Add new netd event callback for changes to NAT64 prefix

Bug: 78545619
Test: system/netd/tests/runtests.sh pass
Test: Register a callback in ConnectivityService temporarily and print out
event parameters. Check event parameters as expected in logs while NAT64 prefix
is added and removed.

Change-Id: I11b2b0aeb159d5fe8dc01ccf6dc64bd9d4d960a5
---
 core/java/android/net/INetdEventCallback.aidl      | 14 ++++++++++++++
 .../android/server/net/BaseNetdEventCallback.java  |  6 ++++++
 .../connectivity/NetdEventListenerService.java     | 13 +++++++++++++
 3 files changed, 33 insertions(+)

diff --git a/core/java/android/net/INetdEventCallback.aidl b/core/java/android/net/INetdEventCallback.aidl
index 4b1a08ded9d6a..0877a1a47e2be 100644
--- a/core/java/android/net/INetdEventCallback.aidl
+++ b/core/java/android/net/INetdEventCallback.aidl
@@ -44,6 +44,20 @@ oneway interface INetdEventCallback {
     void onDnsEvent(int netId, int eventType, int returnCode, String hostname,
             in String[] ipAddresses, int ipAddressesCount, long timestamp, int uid);
 
+    /**
+     * Represents adding or removing a NAT64 prefix.
+     * This method must not block or perform long-running operations.
+     *
+     * @param netId the ID of the network the prefix was performed on.
+     * @param added true if the NAT64 prefix was added, or false if the NAT64 prefix was removed.
+     *        There is only one prefix at a time for each netId. If a prefix is added, it replaces
+     *        the previous-added prefix.
+     * @param prefixString the detected NAT64 prefix as a string literal.
+     * @param prefixLength the prefix length associated with this NAT64 prefix.
+     */
+    void onNat64PrefixEvent(int netId, boolean added, @utf8InCpp String prefixString,
+            int prefixLength);
+
     /**
      * Represents a private DNS validation success or failure.
      * This method must not block or perform long-running operations.
diff --git a/core/java/com/android/server/net/BaseNetdEventCallback.java b/core/java/com/android/server/net/BaseNetdEventCallback.java
index 97247aada49d5..a65214a1edca7 100644
--- a/core/java/com/android/server/net/BaseNetdEventCallback.java
+++ b/core/java/com/android/server/net/BaseNetdEventCallback.java
@@ -31,6 +31,12 @@ public class BaseNetdEventCallback extends INetdEventCallback.Stub {
         // default no-op
     }
 
+    @Override
+    public void onNat64PrefixEvent(int netId, boolean added, String prefixString,
+            int prefixLength) {
+        // default no-op
+    }
+
     @Override
     public void onPrivateDnsValidationEvent(int netId, String ipAddress,
             String hostname, boolean validated) {
diff --git a/services/core/java/com/android/server/connectivity/NetdEventListenerService.java b/services/core/java/com/android/server/connectivity/NetdEventListenerService.java
index 422f5566eee18..e40949b785d91 100644
--- a/services/core/java/com/android/server/connectivity/NetdEventListenerService.java
+++ b/services/core/java/com/android/server/connectivity/NetdEventListenerService.java
@@ -214,6 +214,19 @@ public class NetdEventListenerService extends INetdEventListener.Stub {
         }
     }
 
+    @Override
+    // Called concurrently by multiple binder threads.
+    // This method must not block or perform long-running operations.
+    public synchronized void onNat64PrefixEvent(int netId,
+            boolean added, String prefixString, int prefixLength)
+            throws RemoteException {
+        for (INetdEventCallback callback : mNetdEventCallbackList) {
+            if (callback != null) {
+                callback.onNat64PrefixEvent(netId, added, prefixString, prefixLength);
+            }
+        }
+    }
+
     @Override
     // Called concurrently by multiple binder threads.
     // This method must not block or perform long-running operations.