Custom Password Hasher

CustomPasswordHasher.cs

    public class CustomPasswordHasher : IPasswordHasher
    {
        public IPasswordHasher<User> AspNetPasswordHasher { get; set; }

        public byte Version => throw new NotImplementedException();

        public CustomPasswordHasher(IPasswordHasher<User> ph)
        {
            AspNetPasswordHasher = ph;
        }

        public string HashPassword(string password)
        {
            return AspNetPasswordHasher.HashPassword(null, password);
        }

        public bool VerifyPassword(string hashedPassword, string providedPassword, out bool needsRehash)
        {
            var result = AspNetPasswordHasher.VerifyHashedPassword(null, hashedPassword, providedPassword);

            needsRehash = false;

            switch (result)
            {
                case PasswordVerificationResult.SuccessRehashNeeded:
                case PasswordVerificationResult.Success:
                    needsRehash = true;
                    return true;
                case PasswordVerificationResult.Failed:
                    return false;
                default:
                    return false;
            }
        }
    }