title: How to generate hash using specified salt and password in asp.net Identity?
body: <p>I am currently using the new ASP.NET Identity framework.</p>
  
  <p>I must implement a way of checking if a password the user wishes to change their password to has been used in the past. I have a table containing retired hashes and their corresponding salts.</p>
  
  <p>What I am unable to figure out is how to generate a hash using a specific salt so I can compare the new password to the retired passwords. I've seen <strong>UserManager.PasswordHasher.HashPassword(password)</strong> but I don't see an overload to specify the salt.</p>
  
  <p>How does one go about hashing a password with Identity and specify a salt?</p>