passman/src/Password.hs
2018-12-13 11:15:26 -05:00

79 lines
2.1 KiB
Haskell

{-|
Module: Password
Description: a simple password manager
Copyright: (C) 2018 Jonathan Lamothe
License: LGPLv3 (or later)
Maintainer: jlamothe1980@gmail.com
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as
published by the Free Software Foundation, either version 3 of the
License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this program. If not, see
<https://www.gnu.org/licenses/>.
-}
{-# LANGUAGE TemplateHaskell #-}
module Password (
-- * Data Types
PWPolicy (..),
-- ** Lenses
-- $lenses
pwLength, pwUpper, pwLower, pwDigits, pwSpecial,
-- ** Default Instances
newPWPolicy,
-- * Functions
validatePWPolicy
) where
import Control.Lens (makeLenses, (^.))
import Data.Maybe (fromMaybe)
-- | defines a password policy
data PWPolicy = PWPolicy
{ _pwLength :: Int
-- ^ password length
, _pwUpper :: Int
-- ^ the minimum number of upper case characters
, _pwLower :: Int
-- ^ the minimum number of lower case characters
, _pwDigits :: Int
-- ^ the minimum number of digits
, _pwSpecial :: Maybe Int
-- ^ the minimum number of non-alphanumeric characters (not allowed
-- if @"Nothing"@)
} deriving (Eq, Show)
-- $lenses The following functions are automatically generated by
-- @makeLenses@. See the
-- [lens](http://hackage.haskell.org/package/lens) package for further
-- details.
makeLenses ''PWPolicy
-- | default password policy
newPWPolicy :: PWPolicy
newPWPolicy = PWPolicy 16 0 0 0 (Just 0)
-- | validates a password policy
validatePWPolicy
:: PWPolicy
-- ^ the policy being validated
-> Bool
-- ^ indicates whether or not the policy is valid
validatePWPolicy x = needed <= x^.pwLength where
needed = x^.pwUpper + x^.pwLower + x^.pwDigits + special
special = fromMaybe 0 $ x^.pwSpecial
--jl