WifiConfigStorLegacy: Add null check during restore

One of our OEM's is running into a crash in the config store migration
logic added in O. See the below bug for more details. This issue is not
seen on Pixel devices, because the |configKey| can never be null there.

Also, added a wrapper for IpConfigStore to help in mocking static
method in IpConfigstore.

Note: This code is pretty much unused on Pixel devices & other OEM's
who have upgraded from N to O. Only will help OEM's who upgrade from N
to P directly.

Bug: 73877225
Test: Unit tests
Change-Id: I1b24c05bbb2bc488d77f3f93ec550517c1d1e5c3

2 files changed, 19 insertions, 6 deletions

diff --git a/service/java/com/android/server/wifi/WifiConfigStoreLegacy.java b/service/java/com/android/server/wifi/WifiConfigStoreLegacy.java
index 184ee2f67..ef6d82f31 100644
--- a/service/java/com/android/server/wifi/WifiConfigStoreLegacy.java
+++ b/service/java/com/android/server/wifi/WifiConfigStoreLegacy.java
@@ -81,16 +81,28 @@ public class WifiConfigStoreLegacy {
      */
     private final WifiNetworkHistory mWifiNetworkHistory;
     private final WifiNative mWifiNative;
-    private final IpConfigStore mIpconfigStore;
+    private final IpConfigStoreWrapper mIpconfigStoreWrapper;
 
     private final LegacyPasspointConfigParser mPasspointConfigParser;
 
+    /**
+     * Used to help mocking the static methods of IpconfigStore.
+     */
+    public static class IpConfigStoreWrapper {
+        /**
+         * Read IP configurations from Ip config store.
+         */
+        public SparseArray<IpConfiguration> readIpAndProxyConfigurations(String filePath) {
+            return IpConfigStore.readIpAndProxyConfigurations(filePath);
+        }
+    }
+
     WifiConfigStoreLegacy(WifiNetworkHistory wifiNetworkHistory,
-            WifiNative wifiNative, IpConfigStore ipConfigStore,
+            WifiNative wifiNative, IpConfigStoreWrapper ipConfigStore,
             LegacyPasspointConfigParser passpointConfigParser) {
         mWifiNetworkHistory = wifiNetworkHistory;
         mWifiNative = wifiNative;
-        mIpconfigStore = ipConfigStore;
+        mIpconfigStoreWrapper = ipConfigStore;
         mPasspointConfigParser = passpointConfigParser;
     }
 
@@ -105,7 +117,7 @@ public class WifiConfigStoreLegacy {
     private static WifiConfiguration lookupWifiConfigurationUsingConfigKeyHash(
             Map<String, WifiConfiguration> configurationMap, int hashCode) {
         for (Map.Entry<String, WifiConfiguration> entry : configurationMap.entrySet()) {
-            if (entry.getKey().hashCode() == hashCode) {
+            if (entry.getKey() != null && entry.getKey().hashCode() == hashCode) {
                 return entry.getValue();
             }
         }
@@ -122,7 +134,8 @@ public class WifiConfigStoreLegacy {
         // This is a map of the hash code of the network's configKey to the corresponding
         // IpConfiguration.
         SparseArray<IpConfiguration> ipConfigurations =
-                mIpconfigStore.readIpAndProxyConfigurations(IP_CONFIG_FILE.getAbsolutePath());
+                mIpconfigStoreWrapper.readIpAndProxyConfigurations(
+                        IP_CONFIG_FILE.getAbsolutePath());
         if (ipConfigurations == null || ipConfigurations.size() == 0) {
             Log.w(TAG, "No ip configurations found in ipconfig store");
             return;
diff --git a/service/java/com/android/server/wifi/WifiInjector.java b/service/java/com/android/server/wifi/WifiInjector.java
index 32bf1aed3..a1ecca2c7 100644
--- a/service/java/com/android/server/wifi/WifiInjector.java
+++ b/service/java/com/android/server/wifi/WifiInjector.java
@@ -214,7 +214,7 @@ public class WifiInjector {
         mWifiNetworkHistory = new WifiNetworkHistory(mContext, writer);
         mIpConfigStore = new IpConfigStore(writer);
         mWifiConfigStoreLegacy = new WifiConfigStoreLegacy(
-                mWifiNetworkHistory, mWifiNative, mIpConfigStore,
+                mWifiNetworkHistory, mWifiNative, new WifiConfigStoreLegacy.IpConfigStoreWrapper(),
                 new LegacyPasspointConfigParser());
         // Config Manager
         mWifiConfigManager = new WifiConfigManager(mContext, mClock,