/*
* Copyright 2012 The Stanford MobiSocial Laboratory
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package mobisocial.musubi.nearby.scanner;
import gnu.trove.list.array.TByteArrayList;
import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.nio.ByteBuffer;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.security.spec.AlgorithmParameterSpec;
import java.util.Arrays;
import java.util.HashSet;
import java.util.List;
import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import mobisocial.crypto.IBHashedIdentity.Authority;
import mobisocial.musubi.nearby.item.NearbyFeed;
import mobisocial.musubi.nearby.item.NearbyItem;
import mobisocial.musubi.nearby.location.GridHandler;
import mobisocial.musubi.ui.MusubiBaseActivity;
import mobisocial.musubi.util.MyLocation;
import mobisocial.musubi.util.Util;
import org.apache.http.HttpResponse;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.DefaultHttpClient;
import org.json.JSONArray;
import org.json.JSONObject;
import android.content.Context;
import android.location.Location;
import android.net.Uri;
import android.util.Base64;
import android.util.Log;
import org.javatuples.Pair;
/**
* Pings a server with GPS information to search for nearby items.
*/
public class GpsScannerTask extends NearbyScannerTask {
private final boolean DBG = MusubiBaseActivity.DBG;
private final Context mContext;
private final String mmPassword;
private final MyLocation mmMyLocation;
private boolean mmLocationScanComplete = false;
private Location mmLocation = null;
public GpsScannerTask(Context context, String password) {
mmPassword = password;
mmMyLocation = new MyLocation();
mContext = context;
}
@Override
protected void onPreExecute() {
mmMyLocation.getLocation(mContext, mmLocationResult);
}
@Override
protected List<NearbyItem> doInBackground(Void... params) {
if (DBG) Log.d(TAG, "Scanning for nearby gps...");
while (!mmLocationScanComplete) {
synchronized (mmLocationResult) {
if (!mmLocationScanComplete) {
try {
if (DBG) Log.d(TAG, "Waiting for location results...");
mmLocationResult.wait();
} catch (InterruptedException e) {
}
}
}
}
if (DBG) Log.d(TAG, "Got location " + mmLocation);
if (isCancelled()) {
return null;
}
try {
if (DBG) Log.d(TAG, "Querying gps server...");
Uri uri = Uri.parse("http://bumblebee.musubi.us:6253/nearbyapi/0/findgroup");
StringBuffer sb = new StringBuffer();
DefaultHttpClient client = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(uri.toString());
httpPost.addHeader("Content-Type", "application/json");
JSONArray buckets = new JSONArray();
double lat = mmLocation.getLatitude();
double lng = mmLocation.getLongitude();
long[] coords = GridHandler.getGridCoords(lat, lng, 5280 / 2);
Log.i(TAG, "coords: " + Arrays.toString(coords));
//TODO: encrypt coords with mmPassword
for(long c : coords) {
MessageDigest md;
try {
byte[] obfuscate = ("sadsalt193s" + mmPassword).getBytes();
md = MessageDigest.getInstance("SHA-256");
ByteBuffer b = ByteBuffer.allocate(8 + obfuscate.length);
b.putLong(c);
b.put(obfuscate);
String secret_bucket = Base64.encodeToString(md.digest(b.array()), Base64.DEFAULT);
buckets.put(buckets.length(), secret_bucket);
} catch (NoSuchAlgorithmException e) {
throw new RuntimeException("your platform does not support sha256", e);
}
}
Log.i(TAG, "buckets: " + buckets);
httpPost.setEntity(new StringEntity(buckets.toString()));
try {
HttpResponse execute = client.execute(httpPost);
InputStream content = execute.getEntity().getContent();
BufferedReader buffer = new BufferedReader(new InputStreamReader(content));
String s = "";
while ((s = buffer.readLine()) != null) {
if (isCancelled()) {
return null;
}
sb.append(s);
}
} catch (Exception e) {
e.printStackTrace();
}
HashSet<Pair<TByteArrayList, TByteArrayList>> dupes = new HashSet<Pair<TByteArrayList, TByteArrayList>>();
String response = sb.toString();
JSONArray groupsJSON = new JSONArray(response);
Log.d(TAG, "Got " + groupsJSON.length() + " groups");
for (int i = 0; i < groupsJSON.length(); i++) {
try {
String s_enc_data = groupsJSON.get(i).toString();
byte[] enc_data = Base64.decode(s_enc_data, Base64.DEFAULT);
byte[] key = Util.sha256(("happysalt621" + mmPassword).getBytes());
byte[] data;
Cipher cipher;
AlgorithmParameterSpec iv_spec;
SecretKeySpec sks;
try {
cipher = Cipher.getInstance("AES/CBC/PKCS7Padding");
} catch (Exception e) {
throw new RuntimeException("AES not supported on this platform", e);
}
try {
iv_spec = new IvParameterSpec(enc_data, 0, 16);
sks = new SecretKeySpec(key, "AES");
cipher.init(Cipher.DECRYPT_MODE, sks, iv_spec);
} catch (Exception e) {
throw new RuntimeException("bad iv or key", e);
}
try {
data = cipher.doFinal(enc_data, 16, enc_data.length - 16);
} catch (Exception e) {
throw new RuntimeException("body decryption failed", e);
}
JSONObject group = new JSONObject(new String(data));
String group_name = group.getString("group_name");
byte[] group_capability = Base64.decode(group.getString("group_capability"), Base64.DEFAULT);
String sharer_name = group.getString("sharer_name");
byte[] sharer_hash = Base64.decode(group.getString("sharer_hash"), Base64.DEFAULT);
byte[] thumbnail = null;
if(group.has("thumbnail"))
thumbnail = Base64.decode(group.getString("thumbnail"), Base64.DEFAULT);
int member_count = group.getInt("member_count");
int sharer_type = group.getInt("sharer_type");
Pair<TByteArrayList, TByteArrayList> p = Pair.with(new TByteArrayList(sharer_hash), new TByteArrayList(group_capability));
if(dupes.contains(p))
continue;
dupes.add(p);
addNearbyItem(new NearbyFeed(mContext, group_name, group_capability, sharer_name, Authority.values()[sharer_type], sharer_hash, thumbnail, member_count));
} catch(Throwable e) {
Log.e(TAG, "Failed to parse group " + i, e);
}
}
} catch (Exception e) {
if (DBG) Log.d(TAG, "Error searching nearby feeds", e);
}
return null;
}
private final MyLocation.LocationResult mmLocationResult = new MyLocation.LocationResult() {
@Override
public void gotLocation(final Location location) {
if (DBG) Log.d(TAG, "got location");
mmLocation = location;
mmLocationScanComplete = true;
synchronized (mmLocationResult) {
mmLocationResult.notify();
}
}
};
}