/*
* 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;
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.SecureRandom;
import java.security.spec.AlgorithmParameterSpec;
import java.util.Date;
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.App;
import mobisocial.musubi.model.MFeed;
import mobisocial.musubi.model.MIdentity;
import mobisocial.musubi.model.helpers.FeedManager;
import mobisocial.musubi.model.helpers.IdentitiesManager;
import mobisocial.musubi.nearby.location.GridHandler;
import mobisocial.musubi.ui.MusubiBaseActivity;
import mobisocial.musubi.ui.util.UiUtil;
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.database.sqlite.SQLiteOpenHelper;
import android.location.Location;
import android.net.Uri;
import android.os.AsyncTask;
import android.util.Base64;
import android.util.Log;
import android.widget.Toast;
/**
* Shares a feed encrypted using the GPS server.
*/
public class GpsBroadcastTask extends AsyncTask<Void, Void, Void> {
private final boolean DBG = MusubiBaseActivity.DBG;
public static final String TAG = "GpsBroadcastTask";
private final Context mContext;
private final String mmPassword;
private final MyLocation mmMyLocation;
private boolean mmLocationScanComplete = false;
private Location mmLocation = null;
private MFeed mFeed = null;
private boolean mSucceeded = false;
public GpsBroadcastTask(Context context, MFeed feed, String password) {
mmPassword = password;
mmMyLocation = new MyLocation();
mContext = context;
mFeed = feed;
}
@Override
protected void onPreExecute() {
mmMyLocation.getLocation(mContext, mmLocationResult);
}
@Override
protected Void doInBackground(Void... params) {
if (DBG) Log.d(TAG, "Uploading group 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 {
SQLiteOpenHelper db = App.getDatabaseSource(mContext);
FeedManager fm = new FeedManager(db);
IdentitiesManager im = new IdentitiesManager(db);
String group_name = UiUtil.getFeedNameFromMembersList(fm, mFeed);
byte[] group_capability = mFeed.capability_;
List<MIdentity> owned = im.getOwnedIdentities();
MIdentity sharer = null;
for(MIdentity i : owned) {
if(i.type_ != Authority.Local) {
sharer = i;
break;
}
}
String sharer_name = UiUtil.safeNameForIdentity(sharer);
byte[] sharer_hash = sharer.principalHash_;
byte[] thumbnail = fm.getFeedThumbnailForId(mFeed.id_);
if(thumbnail == null)
thumbnail = im.getMusubiThumbnail(sharer) != null ? sharer.musubiThumbnail_ : im.getThumbnail(sharer);
int member_count = fm.getFeedMemberCount(mFeed.id_);
JSONObject group = new JSONObject();
group.put("group_name", group_name);
group.put("group_capability", Base64.encodeToString(group_capability, Base64.DEFAULT));
group.put("sharer_name", sharer_name);
group.put("sharer_type", sharer.type_.ordinal());
group.put("sharer_hash", Base64.encodeToString(sharer_hash, Base64.DEFAULT));
if(thumbnail != null)
group.put("thumbnail", Base64.encodeToString(thumbnail, Base64.DEFAULT));
group.put("member_count", member_count);
byte[] key = Util.sha256(("happysalt621" + mmPassword).getBytes());
byte[] data = group.toString().getBytes();
byte[] iv = new byte[16];
new SecureRandom().nextBytes(iv);
byte[] partial_enc_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(iv);
sks = new SecretKeySpec(key, "AES");
cipher.init(Cipher.ENCRYPT_MODE, sks, iv_spec);
} catch (Exception e) {
throw new RuntimeException("bad iv or key", e);
}
try {
partial_enc_data = cipher.doFinal(data);
} catch (Exception e) {
throw new RuntimeException("body encryption failed", e);
}
TByteArrayList bal = new TByteArrayList(iv.length + partial_enc_data.length);
bal.add(iv);
bal.add(partial_enc_data);
byte[] enc_data = bal.toArray();
if (DBG) Log.d(TAG, "Posting to gps server...");
Uri uri = Uri.parse("http://bumblebee.musubi.us:6253/nearbyapi/0/sharegroup");
StringBuffer sb = new StringBuffer();
DefaultHttpClient client = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(uri.toString());
httpPost.addHeader("Content-Type", "application/json");
JSONArray buckets = new JSONArray();
JSONObject descriptor = new JSONObject();
double lat = mmLocation.getLatitude();
double lng = mmLocation.getLongitude();
long[] coords = GridHandler.getGridCoords(lat, lng, 5280 / 2);
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);
}
}
descriptor.put("buckets", buckets);
descriptor.put("data", Base64.encodeToString(enc_data, Base64.DEFAULT));
descriptor.put("expiration", new Date().getTime() + 1000 * 60 * 60);
httpPost.setEntity(new StringEntity(descriptor.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);
}
if(sb.toString().equals("ok"))
mSucceeded = true;
else {
System.err.println(sb);
}
} catch (Exception e) {
e.printStackTrace();
}
//TODO: report failures etc
} catch (Exception e) {
Log.e(TAG, "Failed to broadcast group", e);
}
return null;
}
@Override
protected void onPostExecute(Void result) {
Toast.makeText(mContext, mSucceeded ? "Shared group nearby" : "Error sharing group" , Toast.LENGTH_LONG).show();
}
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();
}
}
};
}