Merge pull request #27 from eskimor/warnings

Added warning about resource leakage

Crypto/Classes.hs

@@ -490,6 +490,7 @@ class AsymCipher p v | p -> v, v -> p where
   privateKeyLength :: v -> BitLength
 
 -- |Build a pair of asymmetric keys using the system random generator.
+--   WARNING: This function opens a file handle which will never be closed!
 buildKeyPairIO :: AsymCipher p v => BitLength -> IO (Either GenError (p,v))
 buildKeyPairIO bl = do
         g <- newGenIO :: IO SystemRandom
@@ -542,6 +543,7 @@ class (Serialize p, Serialize v) => Signing p v | p -> v, v -> p  where
   verifyingKeyLength :: p -> BitLength
 
 -- |Build a signing key using the system random generator
+--   WARNING: This function opens a file handle which will never be closed!
 buildSigningKeyPairIO :: (Signing p v) => BitLength -> IO (Either GenError (p,v))
 buildSigningKeyPairIO bl = do
         g <- newGenIO :: IO SystemRandom

Crypto/Random.hs

@@ -162,6 +162,7 @@ class CryptoRandomGen g where
 
         -- |By default this uses "System.Entropy" to obtain
         -- entropy for `newGen`.
+        -- WARNING: The default implementation opens a file handle which will never be closed!
         newGenIO :: IO g
         newGenIO = go 0
           where
@@ -178,7 +179,8 @@ class CryptoRandomGen g where
                         Left _ -> go (i+1)
                         Right g -> return (g `asProxyTypeOf` p)
 
--- |Get a random number generator based on the standard system entropy source
+-- | Get a random number generator based on the standard system entropy source
+--   WARNING: This function opens a file handle which will never be closed!
 getSystemGen :: IO SystemRandom
 getSystemGen = do
         ch <- openHandle