A slightly less insecure wrapper for SharedUserPreferences for Android. Keys and values encrypted using a symmetric cipher.
Clone or download
Fetching latest commit…
Cannot retrieve the latest commit at this time.
Permalink
Type Name Latest commit message Commit time
Failed to load latest commit information.
src Fixed faulty decryption Jul 9, 2012
README.md More readme info Jun 4, 2012

README.md

encrypted-userprefs

An encrypted and slightly less insecure wrapper for SharedPreferences for Android. SharedPreferences on Android stores all of your values in "plain text", simply protected by the user-restricted file system on Android. If you gain root access to an Android device you have full read/write access to the application preferences of all of the applications installed.

Many applications store some kind of application secret (e.g. a communication token, last used account number) using SharedPreferences.

By using this class you'll protect your preferences with a strong and proven symmetric cipher (AES) which will make it harder for anyone wishing to extract information from your application.

PS: This will not make your application bulletproof, just better :)

Example:

A regular shared preference file looks like this from adb shell:

cat /data/data/your.package.application/shared_prefs/prefs-test.xml
<?xml version='1.0' encoding='utf-8' standalone='yes' ?>
<map>
<string name="hemmelighet">dette er en hemmelighet</string>
</map>

With encryption you get a less obvious version:

cat /data/data/your.package.application/shared_prefs/prefs-test.xml
<?xml version='1.0' encoding='utf-8' standalone='yes' ?>
<map>
<string name="JopRH053b7Ogw17Yxmh7Og==">0AB7Y28XEvbQcnXpEZ4j9PtqzFLtm2V3KBXjTO1V704=</string>
</map>

The key is "hemmelighet" and the value is "dette er en hemmelighet".

Usage:

// Init
SecurePreferences preferences = new SecurePreferences(context, "my-preferences", "SometopSecretKey1235", true);
// Put (all puts are automatically committed)
preferences.put("userId", "User1234");
// Get
String user = preferences.getString("userId");

Requirements and limitation:

Android API Level 8 (for Base64 support). Only strings put/gets are supported for now, this should cover most usages.