.net implementation of bcrypt

BCrypt.Net seems to be a most popular library at this moment

http://bcrypt.codeplex.com/

Here is an example how to use it for hashing password:

[TestMethod]
    public void BCryptTest()
    {
        const string password = "PASSWORD";
        const int workFactor = 13;

        var start = DateTime.UtcNow;
        var hashed = BCrypt.Net.BCrypt.HashPassword(password, workFactor);
        var end = DateTime.UtcNow;

        Console.WriteLine("hash length is {0} chars", hashed.Length);
        Console.WriteLine("Processing time is {0} with workFactor {1}", end - start, workFactor);
        Console.WriteLine("Hashed password: {0} ", hashed);
        Console.WriteLine("correct password {0}", BCrypt.Net.BCrypt.Verify("PASSWORD", hashed));
        Console.WriteLine("incorrect password {0}", BCrypt.Net.BCrypt.Verify("PASSWORd", hashed));
    }

Sample output:

hash length is 60 chars
Processing time is 00:00:01.0020000 with workFactor 13
Hashed password: $2a$13$iBqdG7ENBABEargiyzGlTexPsmviF/qrFxUZB2zce7HKF6MoBNhEq 
correct password True
incorrect password False

You can find an updated implementation of BCrypt for .Net here: http://bcrypt.codeplex.com/

It sounds like you are looking for BCrypt.net:

BCrypt.net is an implementation of OpenBSD's Blowfish-based password hashing code, described in "A Future-Adaptable Password Scheme" by Niels Provos and David Mazières. It is a direct port of jBCrypt by Damien Miller, and is thus released under the same BSD-style license. The code is fully managed and should work with any little-endian CLI implementation -- it has been tested with Microsoft .NET and Mono.