AES 0.2.4 → 0.2.5

raw patch · 2 files changed

+69/−3 lines, 2 filesdep +cerealdep +randomPVP ok

version bump matches the API change (PVP)

Dependencies added: cereal, random

API changes (from Hackage documentation)

Files

• AES.cabal +5/−3
• Codec/Crypto/AES/Random.hs +64/−0

@@ -1,7 +1,7 @@ Name: AES Synopsis: Fast AES encryption/decryption for bytestrings Description: A zero-copy binding to Brian Gladman's AES implementation, including a copy of that implementation-Version: 0.2.4+Version: 0.2.5 License: BSD3 License-file: COPYING Copyright: Copyright (c) 2009 University of Tromsø@@ -18,7 +18,8 @@  Library   Build-Depends:-        base >= 4 && < 5 , bytestring, monads-tf >= 0.0.0.1 && < 0.1, transformers >= 0.1.4.0 && < 0.2+        base >= 4 && < 5 , bytestring, monads-tf >= 0.0.0.1 && < 0.1, transformers >= 0.1.4.0 && < 0.2,+        random, cereal >= 0.2   Extensions:         ForeignFunctionInterface,         ViewPatterns,@@ -28,7 +29,8 @@         Control.Monad.UnsafeIO,         Codec.Crypto.AES,         Codec.Crypto.AES.Monad,-        Codec.Crypto.AES.IO+        Codec.Crypto.AES.IO,+        Codec.Crypto.AES.Random    ghc-options: -Wall   

@@ -0,0 +1,64 @@+-- | This module provides a cryptographically secure PRNG based on+-- AES, reading the seed from /dev/random+module Codec.Crypto.AES.Random(randBytes,prandBytes,AESGen,newAESGen) where++import Data.Serialize+import System.IO.Unsafe+import System.IO+import System.Random+import Control.Applicative+import Prelude hiding(head)+import Codec.Crypto.AES.IO+import Control.Concurrent.MVar+import qualified Data.ByteString as B+import qualified Data.ByteString.Lazy as BL+import Data.List++-- | Randomness from a system source of nonsense such as /dev/random+randBytes :: Int -> IO B.ByteString+randBytes n = withFile "/dev/urandom" ReadMode $ \h -> B.hGet h n++{-# NOINLINE ctx #-}+ctx :: MVar AESCtx+ctx = unsafePerformIO $ do+  key <- randBytes 16+  iv <- randBytes 16+  newMVar =<< newCtx CTR key iv Encrypt+  +-- | Cryptographic pseudorandomness from an AES cipher. This function+-- is currently inefficient for non-multiple-of-16 sized bytestrings.+prandBytes :: Int -> IO B.ByteString+prandBytes n = withMVar ctx $ \aesctx -> do+  bytes <- crypt aesctx $ B.replicate (((n+15) `div` 16) * 16) 0+  return $ B.take n bytes++-- | A random number generator that gets its input from prandBytes,+-- ensuring purity by storing those bytes for later if you don't+-- discard the generator.+--+-- Using split on this generator isn't supported, but could be.+--+-- Please note that if an asynchronous exception is caught while a+-- random number is being generated, the generator will be wrecked+-- forevermore.+newtype AESGen = RND [Int]++instance Show AESGen where+  show _ = "AESGen [...]"++instance RandomGen AESGen where+  next (RND (i:is)) = (i,RND is)+  next (RND []) = undefined+  split _ = error "split not supported on Codec.Crypto.AES.Random.AESGen"++intSizeInBinary :: Int+intSizeInBinary = fromIntegral $ B.length $ encode (0::Int)++newAESGen :: IO AESGen+newAESGen = RND <$> gen+  where gen = unsafeInterleaveIO $ do+          bytes <- prandBytes 64+          let chunks = unfoldr (\b -> if B.null b then Nothing else Just (B.splitAt intSizeInBinary b)) bytes+              ints = map ((\(Right i) -> i) . decode) chunks+          moreInts <- gen+          return (ints ++ moreInts)