{-# LANGUAGE ForeignFunctionInterface #-} -- | -- Module : Crypto.Hash.MD2 -- License : BSD-style -- Maintainer : Vincent Hanquez <vincent@snarc.org> -- Stability : experimental -- Portability : unknown -- -- A module containing MD2 bindings -- module Crypto.Hash.MD2 ( Ctx(..) -- * Incremental hashing Functions , init -- :: Ctx , update -- :: Ctx -> ByteString -> Ctx , updates -- :: Ctx -> [ByteString] -> Ctx , finalize -- :: Ctx -> ByteString -- * Single Pass hashing , hash -- :: ByteString -> ByteString , hashlazy -- :: ByteString -> ByteString ) where import Prelude hiding (init) import Foreign.Ptr import Foreign.ForeignPtr (withForeignPtr) import Foreign.Storable import Foreign.Marshal.Alloc import qualified Data.ByteString.Lazy as L import qualified Data.ByteString as B import Data.ByteString (ByteString) import Data.ByteString.Unsafe (unsafeUseAsCStringLen) import Data.ByteString.Internal (create, toForeignPtr) import Data.Word import Crypto.Hash.Internal (unsafeDoIO) -- | MD2 Context newtype Ctx = Ctx ByteString {-# INLINE digestSize #-} digestSize :: Int digestSize = 16 {-# INLINE sizeCtx #-} sizeCtx :: Int sizeCtx = 96 {-# RULES "digestSize" B.length (finalize init) = digestSize #-} {-# RULES "hash" forall b. finalize (update init b) = hash b #-} {-# RULES "hash.list1" forall b. finalize (updates init [b]) = hash b #-} {-# RULES "hashmany" forall b. finalize (foldl update init b) = hashlazy (L.fromChunks b) #-} {-# RULES "hashlazy" forall b. finalize (foldl update init $ L.toChunks b) = hashlazy b #-} {-# INLINE withByteStringPtr #-} withByteStringPtr :: ByteString -> (Ptr Word8 -> IO a) -> IO a withByteStringPtr b f = withForeignPtr fptr $ \ptr -> f (ptr `plusPtr` off) where (fptr, off, _) = toForeignPtr b {-# INLINE memcopy64 #-} memcopy64 :: Ptr Word64 -> Ptr Word64 -> IO () memcopy64 dst src = mapM_ peekAndPoke [0..(12-1)] where peekAndPoke i = peekElemOff src i >>= pokeElemOff dst i withCtxCopy :: Ctx -> (Ptr Ctx -> IO ()) -> IO Ctx withCtxCopy (Ctx ctxB) f = Ctx `fmap` createCtx where createCtx = create sizeCtx $ \dstPtr -> withByteStringPtr ctxB $ \srcPtr -> do memcopy64 (castPtr dstPtr) (castPtr srcPtr) f (castPtr dstPtr) withCtxThrow :: Ctx -> (Ptr Ctx -> IO a) -> IO a withCtxThrow (Ctx ctxB) f = allocaBytes sizeCtx $ \dstPtr -> withByteStringPtr ctxB $ \srcPtr -> do memcopy64 (castPtr dstPtr) (castPtr srcPtr) f (castPtr dstPtr) withCtxNew :: (Ptr Ctx -> IO ()) -> IO Ctx withCtxNew f = Ctx `fmap` create sizeCtx (f . castPtr) withCtxNewThrow :: (Ptr Ctx -> IO a) -> IO a withCtxNewThrow f = allocaBytes sizeCtx (f . castPtr) foreign import ccall unsafe "md2.h md2_init" c_md2_init :: Ptr Ctx -> IO () foreign import ccall "md2.h md2_update" c_md2_update :: Ptr Ctx -> Ptr Word8 -> Word32 -> IO () foreign import ccall unsafe "md2.h md2_finalize" c_md2_finalize :: Ptr Ctx -> Ptr Word8 -> IO () updateInternalIO :: Ptr Ctx -> ByteString -> IO () updateInternalIO ptr d = unsafeUseAsCStringLen d (\(cs, len) -> c_md2_update ptr (castPtr cs) (fromIntegral len)) finalizeInternalIO :: Ptr Ctx -> IO ByteString finalizeInternalIO ptr = create digestSize (c_md2_finalize ptr) {-# NOINLINE init #-} -- | init a context init :: Ctx init = unsafeDoIO $ withCtxNew $ c_md2_init {-# NOINLINE update #-} -- | update a context with a bytestring update :: Ctx -> ByteString -> Ctx update ctx d = unsafeDoIO $ withCtxCopy ctx $ \ptr -> updateInternalIO ptr d {-# NOINLINE updates #-} -- | updates a context with multiples bytestring updates :: Ctx -> [ByteString] -> Ctx updates ctx d = unsafeDoIO $ withCtxCopy ctx $ \ptr -> mapM_ (updateInternalIO ptr) d {-# NOINLINE finalize #-} -- | finalize the context into a digest bytestring finalize :: Ctx -> ByteString finalize ctx = unsafeDoIO $ withCtxThrow ctx finalizeInternalIO {-# NOINLINE hash #-} -- | hash a strict bytestring into a digest bytestring hash :: ByteString -> ByteString hash d = unsafeDoIO $ withCtxNewThrow $ \ptr -> do c_md2_init ptr >> updateInternalIO ptr d >> finalizeInternalIO ptr {-# NOINLINE hashlazy #-} -- | hash a lazy bytestring into a digest bytestring hashlazy :: L.ByteString -> ByteString hashlazy l = unsafeDoIO $ withCtxNewThrow $ \ptr -> do c_md2_init ptr >> mapM_ (updateInternalIO ptr) (L.toChunks l) >> finalizeInternalIO ptr