Remove STOPSHIP but allow seamless Handoff when possible.

If an address is removed we must reset the connection but
only for the connections associated with that address. For
now we're doing the "all" addresses for a type (IPv6 or IPv4)
in the future we only need to reset a particular addresses
connections.


Bug: 4981919
Change-Id: I97f8071a3ed6f827ed22f32216ca5011bfe6c1d9

1 files changed, 54 insertions, 5 deletions

diff --git a/services/java/com/android/server/ConnectivityService.java b/services/java/com/android/server/ConnectivityService.java
index 42be7565e017..812c1eb1d547 100644
--- a/services/java/com/android/server/ConnectivityService.java
+++ b/services/java/com/android/server/ConnectivityService.java
@@ -28,6 +28,7 @@ import android.net.EthernetDataTracker;
 import android.net.IConnectivityManager;
 import android.net.LinkAddress;
 import android.net.LinkProperties;
+import android.net.LinkProperties.CompareAddressesResult;
 import android.net.MobileDataStateTracker;
 import android.net.NetworkConfig;
 import android.net.NetworkInfo;
@@ -61,6 +62,7 @@ import java.io.FileDescriptor;
 import java.io.FileWriter;
 import java.io.IOException;
 import java.io.PrintWriter;
+import java.net.Inet6Address;
 import java.net.InetAddress;
 import java.net.Inet4Address;
 import java.net.UnknownHostException;
@@ -76,6 +78,7 @@ import java.util.List;
 public class ConnectivityService extends IConnectivityManager.Stub {
 
     private static final boolean DBG = true;
+    private static final boolean VDBG = true;
     private static final String TAG = "ConnectivityService";
 
     // how long to wait before switching back to a radio's default network
@@ -99,6 +102,11 @@ public class ConnectivityService extends IConnectivityManager.Stub {
     private NetworkStateTracker mNetTrackers[];
 
     /**
+     * The link properties that define the current links
+     */
+    private LinkProperties mCurrentLinkProperties[];
+
+    /**
      * A per Net list of the PID's that requested access to the net
      * used both as a refcount and for per-PID DNS selection
      */
@@ -302,6 +310,7 @@ public class ConnectivityService extends IConnectivityManager.Stub {
 
         mNetTrackers = new NetworkStateTracker[
                 ConnectivityManager.MAX_NETWORK_TYPE+1];
+        mCurrentLinkProperties = new LinkProperties[ConnectivityManager.MAX_NETWORK_TYPE+1];
 
         mNetworkPreference = getPersistedNetworkPreference();
 
@@ -442,6 +451,7 @@ public class ConnectivityService extends IConnectivityManager.Stub {
                         mNetConfigs[netType].radio);
                 continue;
             }
+            mCurrentLinkProperties[netType] = mNetTrackers[netType].getLinkProperties();
         }
 
         mTethering = new Tethering(mContext, mHandler.getLooper());
@@ -1409,6 +1419,8 @@ public class ConnectivityService extends IConnectivityManager.Stub {
      * right routing table entries exist.
      */
     private void handleConnectivityChange(int netType, boolean doReset) {
+        int resetMask = doReset ? NetworkUtils.RESET_ALL_ADDRESSES : 0;
+
         /*
          * If a non-default network is enabled, add the host routes that
          * will allow it's DNS servers to be accessed.
@@ -1416,6 +1428,45 @@ public class ConnectivityService extends IConnectivityManager.Stub {
         handleDnsConfigurationChange(netType);
 
         if (mNetTrackers[netType].getNetworkInfo().isConnected()) {
+            LinkProperties newLp = mNetTrackers[netType].getLinkProperties();
+            LinkProperties curLp = mCurrentLinkProperties[netType];
+            mCurrentLinkProperties[netType] = newLp;
+            if (VDBG) {
+                log("handleConnectivityChange: changed linkProperty[" + netType + "]:" +
+                        " doReset=" + doReset + " resetMask=" + resetMask +
+                        "\n   curLp=" + curLp +
+                        "\n   newLp=" + newLp);
+            }
+
+            if (curLp.isIdenticalInterfaceName(newLp)) {
+                CompareAddressesResult car = curLp.compareAddresses(newLp);
+                if ((car.removed.size() != 0) || (car.added.size() != 0)) {
+                    for (LinkAddress linkAddr : car.removed) {
+                        if (linkAddr.getAddress() instanceof Inet4Address) {
+                            resetMask |= NetworkUtils.RESET_IPV4_ADDRESSES;
+                        }
+                        if (linkAddr.getAddress() instanceof Inet6Address) {
+                            resetMask |= NetworkUtils.RESET_IPV6_ADDRESSES;
+                        }
+                    }
+                    if (DBG) {
+                        log("handleConnectivityChange: addresses changed" +
+                                " linkProperty[" + netType + "]:" + " resetMask=" + resetMask +
+                                "\n   car=" + car);
+                    }
+                } else {
+                    if (DBG) {
+                        log("handleConnectivityChange: address are the same reset per doReset" +
+                               " linkProperty[" + netType + "]:" +
+                               " resetMask=" + resetMask);
+                    }
+                }
+            } else {
+                resetMask = NetworkUtils.RESET_ALL_ADDRESSES;
+                log("handleConnectivityChange: interface not not equivalent reset both" +
+                        " linkProperty[" + netType + "]:" +
+                        " resetMask=" + resetMask);
+            }
             if (mNetConfigs[netType].isDefault()) {
                 handleApplyDefaultProxy(netType);
                 addDefaultRoute(mNetTrackers[netType]);
@@ -1430,15 +1481,13 @@ public class ConnectivityService extends IConnectivityManager.Stub {
             }
         }
 
-        if (doReset) {
+        if (doReset || resetMask != 0) {
             LinkProperties linkProperties = mNetTrackers[netType].getLinkProperties();
             if (linkProperties != null) {
                 String iface = linkProperties.getInterfaceName();
                 if (TextUtils.isEmpty(iface) == false) {
-                    if (DBG) {
-                        log("resetConnections(" + iface + ", NetworkUtils.RESET_ALL_ADDRESSES)");
-                    }
-                    NetworkUtils.resetConnections(iface, NetworkUtils.RESET_ALL_ADDRESSES);
+                    if (DBG) log("resetConnections(" + iface + ", " + resetMask + ")");
+                    NetworkUtils.resetConnections(iface, resetMask);
                 }
             }
         }