import android.os.Environment;
import android.util.Log;
+import com.hughes.android.dictionary.DictionaryApplication;
+import com.hughes.android.dictionary.DictionaryInfo;
+
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InvalidClassException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
+import java.io.ObjectStreamClass;
import java.io.Serializable;
+import java.util.ArrayList;
+import java.util.HashMap;
import java.util.LinkedHashMap;
import java.util.Map;
public class PersistentObjectCache {
private final File dir;
- private final Map<String, Object> objects = new LinkedHashMap<String, Object>();
+ private final Map<String, Object> objects = new HashMap<String, Object>();
+
+ class ConstrainedOIS extends ObjectInputStream {
+ public ConstrainedOIS(InputStream in) throws IOException {
+ super(in);
+ }
+
+ protected Class<?> resolveClass(ObjectStreamClass desc) throws IOException, ClassNotFoundException {
+ String name = desc.getName();
+ // Note: try to avoid adding more classes.
+ // LinkedHashMap is already more than enough for a DoS
+ if (!name.equals(ArrayList.class.getName()) &&
+ !name.equals(HashMap.class.getName()) &&
+ !name.equals(LinkedHashMap.class.getName()) &&
+ !name.equals(String.class.getName()) &&
+ !name.equals(DictionaryApplication.DictionaryConfig.class.getName()) &&
+ !name.equals(DictionaryInfo.class.getName()) &&
+ !name.equals(DictionaryInfo.IndexInfo.class.getName())) {
+ throw new InvalidClassException("Not allowed to deserialize class", name);
+ }
+ return super.resolveClass(desc);
+ }
+ }
public synchronized <T extends Serializable> T read(final String filename, final Class<T> resultClass) {
try {
Log.d(getClass().getSimpleName(), "File empty: " + src);
return null;
}
+ ObjectInputStream in = null;
try {
- final ObjectInputStream in = new ObjectInputStream(new FileInputStream(src));
+ in = new ConstrainedOIS(new FileInputStream(src));
object = in.readObject();
in.close();
} catch (Exception e) {
Log.e(getClass().getSimpleName(), "Deserialization failed: " + src, e);
+ try {
+ if (in != null) in.close();
+ } catch (IOException e2) {}
return null;
}
objects.put(filename, object);
public synchronized void write(final String filename, final Serializable object) {
objects.put(filename, object);
final File dest = new File(dir, filename);
+ ObjectOutputStream out = null;
try {
- final ObjectOutputStream out = new ObjectOutputStream(new FileOutputStream(dest));
+ out = new ObjectOutputStream(new FileOutputStream(dest));
out.writeObject(object);
- out.close();
} catch (Exception e) {
Log.e(getClass().getSimpleName(), "Serialization failed: " + dest, e);
}
+ try {
+ if (out != null) out.close();
+ } catch (IOException e) {}
}
private PersistentObjectCache(final Context context) {
dir = filesDir != null ? filesDir : Environment.getExternalStorageDirectory();
if (dir == null) {
throw new RuntimeException("context.getFilesDir() == " + context.getFilesDir()
- + ", Environment.getExternalStorageDirectory()="
- + Environment.getExternalStorageDirectory());
+ + ", Environment.getExternalStorageDirectory()="
+ + Environment.getExternalStorageDirectory());
}
}
} else {
if (!instance.dir.equals(context.getFilesDir())) {
throw new RuntimeException("File dir changed. old=" + instance.dir + ", new="
- + context.getFilesDir());
+ + context.getFilesDir());
}
}
return instance;