Interop with Membership Provider

I have a situation where I have been using the Membership provider and wish to migrate to a custom format for the re-work i am doing on OpenID. There is no great reason for not using their structure other than it has a bunch of stuff I really don't need nor will be implementing.

My issue was that the user passwords are SHA-1 hashed and i wanted to simply migrate that data and provide the same implementation so that I don't have hassles checking password or creating new password.

The code below will do that (except for encrypted passwords).

using System;
using System.Text;
using System.Security.Cryptography;

public enum PasswordFormats
{
    Clear,
    Hashed
}

public static class MembershipManager
{
    public static bool IsMatch(string pass, string salt, string encodedPassword)
    {
        string newencoded = EncodePassword(pass, salt);
        return newencoded.Equals(encodedPassword);
    }

    public static string EncodePassword(string pass, string salt)
    {
        return EncodePassword(pass, PasswordFormats.Hashed ,salt);
    }

    public static string EncodePassword(string pass, PasswordFormats format, string salt)
    {
        if (format == PasswordFormats.Clear)
            return pass;

        byte[] bIn = Encoding.Unicode.GetBytes(pass);
        byte[] bSalt = Convert.FromBase64String(salt);
        byte[] bAll = new byte[bSalt.Length + bIn.Length];
        byte[] bRet = null;

        Buffer.BlockCopy(bSalt, 0, bAll, 0, bSalt.Length);
        Buffer.BlockCopy(bIn, 0, bAll, bSalt.Length, bIn.Length);
        HashAlgorithm s = HashAlgorithm.Create("SHA1");
        bRet = s.ComputeHash(bAll);

        return Convert.ToBase64String(bRet);
    }

    public static string GenerateSalt()
    {
        byte[] buf = new byte[16];
        (new RNGCryptoServiceProvider()).GetBytes(buf);
        return Convert.ToBase64String(buf);
    }
}