From 70e5e3eb24c3b0160bdf5093e0407b3b3a10ceaf Mon Sep 17 00:00:00 2001
From: "Chris J. Karr" <chris@audacious-software.com>
Date: Sun, 15 Jan 2017 21:03:50 -0600
Subject: [PATCH] Passive data disclosure work

---
 res/values/generators.xml                     |  2 +-
 .../generators/device/Location.java           | 63 ++++++++++++++++++-
 2 files changed, 62 insertions(+), 3 deletions(-)

diff --git a/res/values/generators.xml b/res/values/generators.xml
index cd52c21..a6e8f0e 100755
--- a/res/values/generators.xml
+++ b/res/values/generators.xml
@@ -65,7 +65,7 @@
     <string name="message_location_accuracy_disabled">This app will not use your location, but use an placeholder instead.</string>
 
     <string name="title_location_accuracy_randomized">Locally Randomized</string>
-    <string name="message_location_accuracy_randomized">Please enter the random distance (miles/kilometers)to use to obfuscate your exact location:</string>
+    <string name="message_location_accuracy_randomized">Please enter the random distance (kilometers) to use to obfuscate your exact location:</string>
 
     <string name="title_location_accuracy_user">User Provided</string>
     <string name="message_location_accuracy_user">Please enter a postal code or city and province to use as your location:</string>
diff --git a/src/com/audacious_software/passive_data_kit/generators/device/Location.java b/src/com/audacious_software/passive_data_kit/generators/device/Location.java
index 64c74b0..7428d53 100755
--- a/src/com/audacious_software/passive_data_kit/generators/device/Location.java
+++ b/src/com/audacious_software/passive_data_kit/generators/device/Location.java
@@ -67,8 +67,10 @@
 
 import java.io.File;
 import java.io.IOException;
+import java.security.SecureRandom;
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Random;
 
 @SuppressWarnings("unused")
 public class Location extends Generator implements GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener, LocationListener {
@@ -312,13 +314,42 @@ public void onConnectionFailed(ConnectionResult connectionResult) {
 
     @Override
     public void onLocationChanged(android.location.Location location) {
-        Log.e("PDK", "LOCATION CHANGED");
-
         if (location == null)
             return;
 
         long now = System.currentTimeMillis();
 
+        final SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(this.mContext);
+        int selected = prefs.getInt(Location.ACCURACY_MODE, Location.ACCURACY_BEST);
+
+        if (selected == Location.ACCURACY_RANDOMIZED) {
+            // http://gis.stackexchange.com/a/68275/10230
+
+            double latitude = location.getLatitude();
+            double longitude = location.getLongitude();
+
+            double radius = prefs.getLong(Location.ACCURACY_MODE_RANDOMIZED_RANGE, Location.ACCURACY_MODE_RANDOMIZED_RANGE_DEFAULT);
+
+            double radiusInDegrees = radius / 111000;
+
+            Random r = new SecureRandom();
+
+            double u = r.nextDouble();
+            double v = r.nextDouble();
+
+            double w = radiusInDegrees * Math.sqrt(u);
+            double t = 2 * Math.PI * v;
+            double x = w * Math.cos(t);
+            double y = w * Math.sin(t);
+
+            // Adjust the x-coordinate for the shrinking of the east-west distances
+            longitude = longitude + (x / Math.cos(latitude));
+            latitude = y + latitude;
+
+            location.setLongitude(longitude);
+            location.setLatitude(latitude);
+        }
+
         ContentValues values = new ContentValues();
         values.put(Location.HISTORY_OBSERVED, System.currentTimeMillis());
         values.put(Location.HISTORY_LATITUDE, location.getLatitude());
@@ -913,6 +944,34 @@ public android.location.Location getLastKnownLocation() {
             }
         }
 
+        if (selected == Location.ACCURACY_RANDOMIZED) {
+            // http://gis.stackexchange.com/a/68275/10230
+
+            double latitude = last.getLatitude();
+            double longitude = last.getLongitude();
+
+            double radius = prefs.getLong(Location.ACCURACY_MODE_RANDOMIZED_RANGE, Location.ACCURACY_MODE_RANDOMIZED_RANGE_DEFAULT);
+
+            double radiusInDegrees = radius / 111000;
+
+            Random r = new SecureRandom();
+
+            double u = r.nextDouble();
+            double v = r.nextDouble();
+
+            double w = radiusInDegrees * Math.sqrt(u);
+            double t = 2 * Math.PI * v;
+            double x = w * Math.cos(t);
+            double y = w * Math.sin(t);
+
+            // Adjust the x-coordinate for the shrinking of the east-west distances
+            longitude = longitude + (x / Math.cos(latitude));
+            latitude = y + latitude;
+
+            last.setLongitude(longitude);
+            last.setLatitude(latitude);
+        }
+
         return last;
     }