1 files changed, 74 insertions, 12 deletions

diff --git a/Data/OpenPGP/Internal.hs b/Data/OpenPGP/Internal.hs
index a4cdc10..a62923a 100644
--- a/Data/OpenPGP/Internal.hs
+++ b/Data/OpenPGP/Internal.hs
@@ -1,17 +1,47 @@
-{-# LANGUAGE BangPatterns, MagicHash #-}
+{-# LANGUAGE BangPatterns #-}
+{-# LANGUAGE CPP          #-}
+{-# LANGUAGE MagicHash    #-}
 module Data.OpenPGP.Internal where
 
-import           Data.Bits
-import qualified Data.ByteString           as BS
-import qualified Data.ByteString.Internal  as BS
-import           Data.Word
-import           Foreign.ForeignPtr
-import           Foreign.Ptr
-import           Foreign.Storable
-import           GHC.Exts
-import           GHC.Integer.GMP.Internals
-import           System.Endian
-import           System.IO.Unsafe
+import Data.Bits
+import qualified Data.ByteString          as BS
+import qualified Data.ByteString.Internal as BS
+import qualified Data.ByteString.Lazy     as BL
+import Data.Char
+import Data.Int
+import Data.Word
+import Foreign.ForeignPtr
+import Foreign.Ptr
+import Foreign.Storable
+import GHC.Exts
+import GHC.Integer.GMP.Internals
+import System.Endian
+import System.IO.Unsafe
+import Numeric (showHex)
+
+#if defined(VERSION_cryptonite)
+import qualified Data.ByteArray as Bytes
+import Crypto.Hash.Algorithms
+import Crypto.Hash
+import Crypto.Error
+#else
+import qualified Data.Byteable as Vincent
+import Crypto.Hash.SHA1 as SHA1
+#endif
+
+#ifdef CEREAL
+import qualified Data.ByteString      as B
+import qualified Data.ByteString.UTF8 as B (fromString, toString)
+import Data.Serialize
+#define BINARY_CLASS Serialize
+#else
+import Data.Binary
+import Data.Binary.Get
+import Data.Binary.Put
+import qualified Data.ByteString.Lazy      as B
+import qualified Data.ByteString.Lazy.UTF8 as B (fromString, toString)
+#define BINARY_CLASS Binary
+#endif
 
 
 
@@ -91,3 +121,35 @@ integerToLE i = BS.unsafeCreate (I# (word2Int# (sizeInBaseInteger i 256#))) $ \p
         let Ptr addr = ptr
         cnt <- exportIntegerToAddr i addr 0#
         return ()
+
+toStrictBS :: B.ByteString -> BS.ByteString
+toStrictBS = BS.concat . B.toChunks
+
+checksum :: B.ByteString -> Word16
+checksum = fromIntegral .
+        B.foldl (\c i -> (c + fromIntegral i) `mod` 65536) (0::Integer)
+
+
+checksumForKey :: Word8 {- s2k_usage byte -} -> (Int64, B.ByteString -> BS.ByteString)
+checksumForKey 254 = (20, sha1 . toStrictBS)
+ where
+#if defined(VERSION_cryptonite)
+    sha1 x = Bytes.convert (hash x :: Digest SHA1)
+#else
+    sha1 = SHA1.hash
+#endif
+checksumForKey _   = (2, toStrictBS . encode . checksum)
+                    -- Words16s are written as 2 bytes in big-endian (network) order
+
+hexString :: [Word8] -> String
+hexString = foldr (pad `oo` showHex) ""
+        where
+        pad s | odd $ length s = '0':s
+              | otherwise = s
+
+        oo :: (b -> c) -> (a -> a1 -> b) -> a -> a1 -> c
+        oo = (.) . (.)
+
+hexify :: BS.ByteString -> String
+hexify = map toUpper . hexString . BS.unpack
+