97
votes

I have to face a new little project. It will have about 7 or 9 tables, the biggest of them will grow by a max rate of 1000 rows a month.

I thought about SQLite as my db... But i will need to protect the db in case anybody wants to change data from the db

My main question is:

Is it possible password protect a sqlite db as you would do on access?

What other RDBMS would you recommend for such a small solution?

The development would be on C#, but i'm searching something free.

8
You might want to check out SQLiteCrypt - Mike Buckbee
If you need to lock/unlock DB frequently for debugging, try this tool goo.gl/12VnQd - Mangesh
You can find the solution here enter link description here - Ishwar Rimal

8 Answers

77
votes

You can password protect a SQLite3 DB. Before doing any operations, set the password as follows.

SQLiteConnection conn = new SQLiteConnection("Data Source=MyDatabase.sqlite;Version=3;");
conn.SetPassword("password");
conn.Open();

then next time you can access it like

conn = new SQLiteConnection("Data Source=MyDatabase.sqlite;Version=3;Password=password;");
conn.Open();

This wont allow any GUI editor to view your data. Some editors can decrypt the DB if you provide the password. The algorithm used is RSA.

Later if you wish to change the password, use

conn.ChangePassword("new_password");

To reset or remove password, use

conn.ChangePassword(String.Empty);
34
votes

You can use the built-in encryption of the sqlite .net provider (System.Data.SQLite). See more details at http://web.archive.org/web/20070813071554/http://sqlite.phxsoftware.com/forums/t/130.aspx

To encrypt an existing unencrypted database, or to change the password of an encrypted database, open the database and then use the ChangePassword() function of SQLiteConnection:

// Opens an unencrypted database
SQLiteConnection cnn = new SQLiteConnection("Data Source=c:\\test.db3");
cnn.Open();
// Encrypts the database. The connection remains valid and usable afterwards.
cnn.ChangePassword("mypassword");

To decrypt an existing encrypted database call ChangePassword() with a NULL or "" password:

// Opens an encrypted database
SQLiteConnection cnn = new SQLiteConnection("Data Source=c:\\test.db3;Password=mypassword");
cnn.Open();
// Removes the encryption on an encrypted database.
cnn.ChangePassword(null);

To open an existing encrypted database, or to create a new encrypted database, specify a password in the ConnectionString as shown in the previous example, or call the SetPassword() function before opening a new SQLiteConnection. Passwords specified in the ConnectionString must be cleartext, but passwords supplied in the SetPassword() function may be binary byte arrays.

// Opens an encrypted database by calling SetPassword()
SQLiteConnection cnn = new SQLiteConnection("Data Source=c:\\test.db3");
cnn.SetPassword(new byte[] { 0xFF, 0xEE, 0xDD, 0x10, 0x20, 0x30 });
cnn.Open();
// The connection is now usable

By default, the ATTACH keyword will use the same encryption key as the main database when attaching another database file to an existing connection. To change this behavior, you use the KEY modifier as follows:

If you are attaching an encrypted database using a cleartext password:

// Attach to a database using a different key than the main database
SQLiteConnection cnn = new SQLiteConnection("Data Source=c:\\test.db3");
cnn.Open();
cmd = new SQLiteCommand("ATTACH DATABASE 'c:\\pwd.db3' AS [Protected] KEY 'mypassword'", cnn);
cmd.ExecuteNonQuery();

To attach an encrypted database using a binary password:

// Attach to a database encrypted with a binary key
SQLiteConnection cnn = new SQLiteConnection("Data Source=c:\\test.db3");
cnn.Open();
cmd = new SQLiteCommand("ATTACH DATABASE 'c:\\pwd.db3' AS [Protected] KEY X'FFEEDD102030'", cnn);
cmd.ExecuteNonQuery();
14
votes

Use SQLCipher, it's an opensource extension for SQLite that provides transparent 256-bit AES encryption of database files. http://sqlcipher.net

6
votes

You can encrypt your SQLite database with the SEE addon. This way you prevent unauthorized access/modification.

Quoting SQLite documentation:

The SQLite Encryption Extension (SEE) is an enhanced version of SQLite that encrypts database files using 128-bit or 256-Bit AES to help prevent unauthorized access or modification. The entire database file is encrypted so that to an outside observer, the database file appears to contain white noise. There is nothing that identifies the file as an SQLite database.

You can find more info about this addon in this link.

3
votes

One option would be VistaDB. They allow databases (or even tables) to be password protected (and optionally encrypted).

3
votes

If you use FluentNHibernate you can use following configuration code:

private ISessionFactory createSessionFactory()
{
    return Fluently.Configure()
            .Database(SQLiteConfiguration.Standard.UsingFileWithPassword(filename, password))
            .Mappings(m => m.FluentMappings.AddFromAssemblyOf<DBManager>())
            .ExposeConfiguration(this.buildSchema)
            .BuildSessionFactory();    
}

private void buildSchema(Configuration config)
{
        if (filename_not_exists == true)
        {
            new SchemaExport(config).Create(false, true);
        }
}    

Method UsingFileWithPassword(filename, password) encrypts a database file and sets password.
It runs only if the new database file is created. The old one not encrypted fails when is opened with this method.

2
votes

I know this is an old question but wouldn't the simple solution be to just protect the file at the OS level? Just prevent the users from accessing the file and then they shouldn't be able to touch it. This is just a guess and I'm not sure if this is an ideal solution.

1
votes

Why do you need to encrypt the database? The user could easily disassemble your program and figure out the key. If you're encrypting it for network transfer, then consider using PGP instead of squeezing an encryption layer into a database layer.