generate password for auth-plug for mosquitto in c# - cryptography

Question

I have spent all day trying to make a usable pbkdf2 password for the mosquitto-auth-plug. This program sets it up exactly the way it should be stored in the mysql database. I have a password hash generated by the program that comes with auth-plug and mosquitto loves it. I just can't replicate it in c#, if anyone can help please let me know.
public string CreatePasswordHash(string password)
{
var salt = GenerateRandomSalt();
var iterationCount = GetIterationCount();
var hashValue = GenerateHashValue(password, salt, iterationCount);
string result = "PBKDF2$sha256$" + iterationCount + "$" + Convert.ToBase64String(salt) + "$" + Convert.ToBase64String(hashValue);
return result;
}
private int GetIterationCount()
{
return 901;
}
private static byte[] GenerateRandomSalt()
{
var csprng = new RNGCryptoServiceProvider();
var salt = new byte[SaltByteLength];
csprng.GetBytes(salt);
return salt;
//return GetLetter();
}
private static byte[] GenerateHashValue(string password, byte[] salt, int iterationCount)
{
byte[] hashValue;
var valueToHash = string.IsNullOrEmpty(password) ? string.Empty : password;
using (var pbkdf2 = new Rfc2898DeriveBytes(valueToHash, salt, iterationCount))
{
hashValue = pbkdf2.GetBytes(DerivedKeyLength);
}
return hashValue;
}
---EDIT-----
Rfc2898DeriveBytes states --
Implements password-based key derivation functionality, PBKDF2, by using psuedo-random number generator based on HMACSHA1.
The program/auth-plug seems to be using sha256 is there a c# PBKDF2 that uses this.

Answer 1

As you have already stated in your edit, the problem appears to be the difference in hash functions used between the mosquitto plugin (which only supports SHA-256, according to the source code) and the .NET implementation (which can only do SHA-1).
A more flexible implementation of PBKDF2 is available in BouncyCastle, a more lightweight implementation can be found here. If you are not satisfied with those two, you could chose to implemnt PBKDF2 yourself, which is not really hard.

Answer 2

Well it appears there really wasn't an answer and there weren't many who had tried. I figured out the problem and after contacting the mosquitto-auth-plug author he felt it would be good for us to add my solution to his contrib folder on the plugins github repo.
So now if you need a c# hashing algorithm for mosquitto-auth-plug just go to the repo in git here
https://github.com/jpmens/mosquitto-auth-plug/tree/master/contrib/C%23
and follow my instructions --- Let me know if you have any problems