implemented newSalt

package.yaml

@@ -24,6 +24,7 @@ dependencies:
 - bytestring
 - containers
 - lens
+- random
 
 library:
   source-dirs: src

src/Password.hs

@@ -34,7 +34,7 @@ module Password (
   -- *** PWPolicy
   pwLength, pwUpper, pwLower, pwDigits, pwSpecial,
   -- ** Default Instances
-  newPWPolicy,
+  newPWPolicy, newSalt,
   -- * Functions
   validatePWPolicy
   ) where
@@ -44,6 +44,7 @@ import Data.Char (isUpper, isLower, isDigit, isAlphaNum)
 import qualified Data.ByteString as B
 import qualified Data.Map as M
 import Data.Maybe (fromMaybe)
+import System.Random (RandomGen, randoms, split)
 
 -- | a mapping of service names to password data
 type PWDatabase = M.Map String PWData
@@ -83,6 +84,17 @@ makeLenses ''PWData
 newPWPolicy :: PWPolicy
 newPWPolicy = PWPolicy 16 0 0 0 (Just 0)
 
+-- | builds a new salt
+newSalt
+  :: RandomGen g
+  => g
+  -- ^ the random generator to use
+  -> (B.ByteString, g)
+  -- ^ the result and new random number generator
+newSalt g = (result, g2) where
+  result = B.pack $ take 256 $ randoms g1
+  (g1, g2) = split g
+
 -- | validates a password policy
 validatePWPolicy
   :: PWPolicy

test/Spec.hs

@@ -26,6 +26,7 @@ import Control.Monad (when)
 import System.Exit (exitFailure)
 import Test.HUnit (errors, failures, runTestTT, Test(TestList))
 
+import qualified Spec.NewSalt as NewSalt
 import qualified Spec.PWPolicy as PWPolicy
 import qualified Spec.ValidatePWPolicy as ValidatePWPolicy
 
@@ -37,6 +38,7 @@ main = do
 tests = TestList
   [ PWPolicy.tests
   , ValidatePWPolicy.tests
+  , NewSalt.tests
   ]
 
 --jl

test/Spec/NewSalt.hs

@@ -0,0 +1,35 @@
+{-
+
+passman
+Copyright (C) 2018 Jonathan Lamothe
+<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/>.
+
+-}
+
+module Spec.NewSalt (tests) where
+
+import qualified Data.ByteString as B
+import System.Random (mkStdGen)
+import Test.HUnit (Test(..), (~?=))
+
+import Password
+
+tests = TestLabel "newSalt" $ B.length salt ~?= 256 where
+  (salt, _) = newSalt g
+  g = mkStdGen 1
+
+--jl