From bff73490ac373f8095f54ebfa26fc30d643bcb54 Mon Sep 17 00:00:00 2001
From: Paul Jensen <pauljensen@google.com>
Date: Mon, 28 Apr 2014 10:33:11 -0400
Subject: [PATCH] Separate network and interface addition/removal netd APIs.
 This should facilitate stacked interfaces (i.e. clatd).

Change-Id: Ib3e7a4d3847ef6ec4449451f6da42e75959baa4f
---
 core/java/android/net/LinkProperties.java     | 29 +++++++++++++++++++
 .../android/server/ConnectivityService.java   | 28 ++++++++++++++++--
 2 files changed, 55 insertions(+), 2 deletions(-)

diff --git a/core/java/android/net/LinkProperties.java b/core/java/android/net/LinkProperties.java
index 2dcc544f6f..0a09fcba4e 100644
--- a/core/java/android/net/LinkProperties.java
+++ b/core/java/android/net/LinkProperties.java
@@ -642,6 +642,35 @@ public class LinkProperties implements Parcelable {
         return result;
     }
 
+    /**
+     * Compares all interface names in this LinkProperties with another
+     * LinkProperties, examining both the the base link and all stacked links.
+     *
+     * @param target a LinkProperties with the new list of interface names
+     * @return the differences between the interface names.
+     * @hide
+     */
+    public CompareResult<String> compareAllInterfaceNames(LinkProperties target) {
+        /*
+         * Duplicate the interface names into removed, we will be removing
+         * interface names which are common between this and target
+         * leaving the interface names that are different. And interface names which
+         * are in target but not in this are placed in added.
+         */
+        CompareResult<String> result = new CompareResult<String>();
+
+        result.removed = getAllInterfaceNames();
+        result.added.clear();
+        if (target != null) {
+            for (String r : target.getAllInterfaceNames()) {
+                if (! result.removed.remove(r)) {
+                    result.added.add(r);
+                }
+            }
+        }
+        return result;
+    }
+
 
     @Override
     /**
diff --git a/services/core/java/com/android/server/ConnectivityService.java b/services/core/java/com/android/server/ConnectivityService.java
index cdb82e76a6..6cc738b763 100644
--- a/services/core/java/com/android/server/ConnectivityService.java
+++ b/services/core/java/com/android/server/ConnectivityService.java
@@ -5088,6 +5088,7 @@ public class ConnectivityService extends IConnectivityManager.Stub {
         LinkProperties newLp = networkAgent.linkProperties;
         int netId = networkAgent.network.netId;
 
+        updateInterfaces(newLp, oldLp, netId);
         updateMtu(newLp, oldLp);
         // TODO - figure out what to do for clat
 //        for (LinkProperties lp : newLp.getStackedLinks()) {
@@ -5096,6 +5097,30 @@ public class ConnectivityService extends IConnectivityManager.Stub {
         updateRoutes(newLp, oldLp, netId);
         updateDnses(newLp, oldLp, netId);
     }
+
+    private void updateInterfaces(LinkProperties newLp, LinkProperties oldLp, int netId) {
+        CompareResult<String> interfaceDiff = new CompareResult<String>();
+        if (oldLp != null) {
+            interfaceDiff = oldLp.compareAllInterfaceNames(newLp);
+        } else if (newLp != null) {
+            interfaceDiff.added = newLp.getAllInterfaceNames();
+        }
+        for (String iface : interfaceDiff.added) {
+            try {
+                mNetd.addInterfaceToNetwork(iface, netId);
+            } catch (Exception e) {
+                loge("Exception adding interface: " + e);
+            }
+        }
+        for (String iface : interfaceDiff.removed) {
+            try {
+                mNetd.removeInterfaceFromNetwork(iface, netId);
+            } catch (Exception e) {
+                loge("Exception removing interface: " + e);
+            }
+        }
+    }
+
     private void updateRoutes(LinkProperties newLp, LinkProperties oldLp, int netId) {
         CompareResult<RouteInfo> routeDiff = new CompareResult<RouteInfo>();
         if (oldLp != null) {
@@ -5300,8 +5325,7 @@ public class ConnectivityService extends IConnectivityManager.Stub {
         if (state == NetworkInfo.State.CONNECTED) {
             // TODO - check if we want it (optimization)
             try {
-                mNetd.createNetwork(networkAgent.network.netId,
-                        networkAgent.linkProperties.getInterfaceName());
+                mNetd.createNetwork(networkAgent.network.netId);
             } catch (Exception e) {
                 loge("Error creating Network " + networkAgent.network.netId);
             }