C# nHibernate programmatically set db password

Question

I have a C# Windows Forms application. We are using nHibernate version 2.1 with Castle. We are installing our application in a secured vault. Therefore, we need to store the password in encrypted format in the hibernate.cfg.xml file. The C# code then decrypts the password. How can I set the nHibernate connectin string password to the decrypted string value in code?

Answer 1

Your best bet is probably to use Configuration.GetProperty and Configuration.SetProperty to modify the configuration defined in your hibernate.cfg.xml file:

var configuration = new Configuration()
    .Configure();

const string connectionStringKey = "connection.connection_string";

string connectionString = configuration.GetProperty(connectionStringKey);
connectionString = Regex.Replace(
    connectionString,
    "Password=(.+);",
    DecryptPasswordMatch);

configuration.SetProperty(connectionStringKey, connectionString);

Where DecryptPasswordMatch is defined as:

static string DecryptPasswordMatch(Match m)
{
    string password = m.Groups[1].Value;

    password = /* some method that decrypts password */;

    return string.Format("Password={0}", password);
}

You'll have to change the regular expression slightly depending on your database engine (this should work for SQL Server).