CMSettings: Validate name and value for System settings

Verify that the name and value being inserted/updated are correct.

Change-Id: I0243556701b1d303ca52135178b055c2fd87671c

packages/CMSettingsProvider/src/org/cyanogenmod/cmsettings/CMSettingsProvider.java

@@ -20,7 +20,6 @@ import android.app.ActivityManager;
 import android.content.BroadcastReceiver;
 import android.content.ContentProvider;
 import android.content.ContentResolver;
-import android.content.ContentUris;
 import android.content.ContentValues;
 import android.content.Context;
 import android.content.Intent;
@@ -29,7 +28,6 @@ import android.content.SharedPreferences;
 import android.content.UriMatcher;
 import android.content.pm.PackageManager;
 import android.content.pm.UserInfo;
-import android.content.res.Configuration;
 import android.database.AbstractCursor;
 import android.database.Cursor;
 import android.database.sqlite.SQLiteDatabase;
@@ -505,12 +503,18 @@ public class CMSettingsProvider extends ContentProvider {
 
         CMDatabaseHelper dbHelper = getOrEstablishDatabase(getUserIdForTable(tableName, userId));
 
+        // Validate value if inserting int System table
+        final String name = values.getAsString(Settings.NameValueTable.NAME);
+        if (CMDatabaseHelper.CMTableNames.TABLE_SYSTEM.equals(tableName)) {
+            final String value = values.getAsString(Settings.NameValueTable.VALUE);
+            validateSystemSettingNameValue(name, value);
+        }
+
         SQLiteDatabase db = dbHelper.getWritableDatabase();
         long rowId = db.insert(tableName, null, values);
 
         Uri returnUri = null;
         if (rowId > -1) {
-            String name = values.getAsString(Settings.NameValueTable.NAME);
             returnUri = Uri.withAppendedPath(uri, name);
             notifyChange(returnUri, tableName, userId);
             if (LOCAL_LOGV) Log.d(TAG, "Inserted row id: " + rowId + " into tableName: " +
@@ -568,6 +572,13 @@ public class CMSettingsProvider extends ContentProvider {
         String tableName = getTableNameFromUri(uri);
         checkWritePermissions(tableName);
 
+        // Validate value if updating System table
+        final String name = values.getAsString(Settings.NameValueTable.NAME);
+        if (CMDatabaseHelper.CMTableNames.TABLE_SYSTEM.equals(tableName)) {
+            final String value = values.getAsString(Settings.NameValueTable.VALUE);
+            validateSystemSettingNameValue(name, value);
+        }
+
         int callingUserId = UserHandle.getCallingUserId();
         CMDatabaseHelper dbHelper = getOrEstablishDatabase(getUserIdForTable(tableName,
                 callingUserId));
@@ -763,5 +774,17 @@ public class CMSettingsProvider extends ContentProvider {
         if (LOCAL_LOGV) Log.v(TAG, "notifying for " + notifyTarget + ": " + uri);
     }
 
+    private void validateSystemSettingNameValue(String name, String value) {
+        CMSettings.System.Validator validator = CMSettings.System.VALIDATORS.get(name);
+        if (validator == null) {
+            throw new IllegalArgumentException("Invalid setting: " + name);
+        }
+
+        if (!validator.validate(value)) {
+            throw new IllegalArgumentException("Invalid value: " + value
+                    + " for setting: " + name);
+        }
+    }
+
     // TODO Add caching
 }