How to implement SQLCipher when using SQLiteOpenHelper

Question

I am trying to secure some sensible data by implementing encryption in my already existing and functioning database setup in an android application.

I tried to follow this tutorial (http://sqlcipher.net/sqlcipher-for-android/) and I browsed a lot of foruns, including the google group for Cipher. However, I still don't clearly understand how does SQLCipher work and how I should adapt my code to serve my needs.

I am following this implementation of databases in android: http://www.vogella.com/articles/AndroidSQLite/#databasetutorial_database, meaning I have an extension of the SQLiteOpenHelper class and another class to store CRUD methods.

In this situation how should I use SQLCipher? Where should I define the password? Where should I use loadLibs(context)? Only in the main activity? Or in every activity that accesses the database?

I feel I'm almost there, I just need the final push to figure this out :P Thanks in advance!

Answer 1

In this situation how should I use SQLCipher?

Exactly like an normal your normal sql implementation.

Where should I define the password?

If you are using SQLiteHelper it will create the database when you first get it like this:

helper.getWriteableDatabase("myPassword");

On the first call it will create the database with this Password. On the upcoing calls it will only work with this password.

( Figured that out when i went to the Source: https://github.com/sqlcipher/android-database-sqlcipher/blob/master/android-database-sqlcipher/src/main/java/net/sqlcipher/database/SQLiteOpenHelper.java, checkout the method getWriteableDatabase( String pw ) there! )

Where should I use loadLibs(context)?

Right before you call helper.getWriteableDatabase("myPassword"); the first time!

Answer 2

In this situation how should I use SQLCipher?

That is impossible to answer in the abstract. You would use it largely the same way that you use SQLite.

Where should I define the password?

You should get it from the user.

Where should I use loadLibs(context)? Only in the main activity? Or in every activity that accesses the database?

Once per process is sufficient (in fact, more could conceivably be a problem). If you are using a ContentProvider for your SQLCipher database, call loadLibs() in onCreate() of the ContentProvider. If you are using a custom Application, call loadLibs() in onCreate() of the Application.