{-# OPTIONS_GHC -XBangPatterns #-} ----------------------------------------------------------------------------- -- -- Module : Data.Digest.MD5 -- License : BSD3 -- Maintainer : Thomas.DuBuisson@mail.google.com -- Stability : experimental -- Portability : portable, requires bang patterns and ByteString -- Tested with : GHC-6.8.1 -- -- |To get an MD5 digest of a lazy ByteString (you probably want this): -- hash = md5 lazyByteString -- -- Alternativly, for a context that can be further updated/finalized: -- partialCtx = md5Update md5InitialContext partOfFile -- -- And you finialize the context with: -- hash = md5Finalize partialCtx ----------------------------------------------------------------------------- module Data.Digest.Pure.MD5 ( -- * Types MD5Context , MD5Digest -- * Static data , md5InitialContext , blockSize -- * Functions , md5 , md5Update , md5Finalize ) where import qualified Data.ByteString as B import qualified Data.ByteString.Lazy as L import Data.ByteString.Internal import Data.Bits import Data.List import Data.Int (Int64) import Foreign.Storable import Foreign.Ptr import Foreign.ForeignPtr import Data.Binary import Data.Binary.Get import Data.Binary.Put import Numeric -- | Block size in bits blockSize :: Int blockSize = 512 blockSizeBytes = blockSize `div` 8 blockSizeBytesI64 = (fromIntegral blockSizeBytes) :: Int64 blockSizeBits = (fromIntegral blockSize) :: Word64 data MD5Partial = MD5Par !Word32 !Word32 !Word32 !Word32 deriving (Ord, Eq) -- | The type for intermediate and final results. data MD5Context = MD5Ctx { mdPartial :: !MD5Partial, mdLeftOver :: ByteString, mdTotalLen :: !Word64 } -- |After finalizing a context, using md5Finalize, a new type -- is returned to prevent 're-finalizing' the structure. newtype MD5Digest = MD5Digest MD5Context -- | The initial context to use when calling md5Update for the first time md5InitialContext :: MD5Context md5InitialContext = MD5Ctx (MD5Par h0 h1 h2 h3) B.empty 0 h0 = 0x67452301 h1 = 0xEFCDAB89 h2 = 0x98BADCFE h3 = 0x10325476 -- | Processes a lazy ByteString and returns the md5 digest. -- This is probably what you want. md5 :: L.ByteString -> MD5Digest md5 bs = md5Finalize $ md5Update md5InitialContext bs -- | Closes an MD5 context, thus producing the digest. md5Finalize :: MD5Context -> MD5Digest md5Finalize !ctx@(MD5Ctx (MD5Par _a _b _c _d) rem !totLen) = let totLen' = (totLen + 8*fromIntegral l) :: Word64 padBS = L.toChunks $ runPut ( do putWord8 0x80 mapM_ putWord8 (replicate lenZeroPad 0) putWord64le totLen' ) in MD5Digest $ md5Update ctx (L.fromChunks padBS) where l = B.length rem lenZeroPad = if (l + 1) <= blockSizeBytes - 8 then (blockSizeBytes - 8) - (l + 1) else (2 * blockSizeBytes - 8) - (l + 1) -- | Alters the MD5Context with a partial digest of the data. md5Update :: MD5Context -> L.ByteString -> MD5Context md5Update !ctx@(MD5Ctx _ !leftover _) bsLazy = let bs = L.fromChunks (leftover:L.toChunks bsLazy) in blockAndDo ctx bs --foldl' performMD5Update ctx blks blockAndDo :: MD5Context -> L.ByteString -> MD5Context blockAndDo !ctx bs = if B.length blk == blockSizeBytes then let !newCtx = performMD5Update ctx blk in blockAndDo newCtx rest else ctx { mdLeftOver = blk } where blk = B.concat $ L.toChunks top (top,rest) = L.splitAt blockSizeBytesI64 bs {-# INLINE blockAndDo #-} -- Assumes ByteString length == blockSizeBytes, will fold the -- context across calls to applyMD5Rounds. performMD5Update :: MD5Context -> ByteString -> MD5Context performMD5Update !_ctx@(MD5Ctx !par@(MD5Par !a !b !c !d) _ !len) !bs = let MD5Par a' b' c' d' = applyMD5Rounds par bs in MD5Ctx { mdPartial = MD5Par (a' + a) (b' + b) (c' + c) (d' + d), mdLeftOver = B.empty, mdTotalLen = len + blockSizeBits } {-# INLINE performMD5Update #-} applyMD5Rounds :: MD5Partial -> ByteString -> MD5Partial applyMD5Rounds _par@(MD5Par a b c d) w = let -- Round 1 !r0 = ff a b c d (w!!0) 7 3614090360 !r1 = ff d r0 b c (w!!1) 12 3905402710 !r2 = ff c r1 r0 b (w!!2) 17 606105819 !r3 = ff b r2 r1 r0 (w!!3) 22 3250441966 !r4 = ff r0 r3 r2 r1 (w!!4) 7 4118548399 !r5 = ff r1 r4 r3 r2 (w!!5) 12 1200080426 !r6 = ff r2 r5 r4 r3 (w!!6) 17 2821735955 !r7 = ff r3 r6 r5 r4 (w!!7) 22 4249261313 !r8 = ff r4 r7 r6 r5 (w!!8) 7 1770035416 !r9 = ff r5 r8 r7 r6 (w!!9) 12 2336552879 !r10 = ff r6 r9 r8 r7 (w!!10) 17 4294925233 !r11 = ff r7 r10 r9 r8 (w!!11) 22 2304563134 !r12 = ff r8 r11 r10 r9 (w!!12) 7 1804603682 !r13 = ff r9 r12 r11 r10 (w!!13) 12 4254626195 !r14 = ff r10 r13 r12 r11 (w!!14) 17 2792965006 !r15 = ff r11 r14 r13 r12 (w!!15) 22 1236535329 -- Round 2 !r16 = gg r12 r15 r14 r13 (w!!1) 5 4129170786 !r17 = gg r13 r16 r15 r14 (w!!6) 9 3225465664 !r18 = gg r14 r17 r16 r15 (w!!11) 14 643717713 !r19 = gg r15 r18 r17 r16 (w!!0) 20 3921069994 !r20 = gg r16 r19 r18 r17 (w!!5) 5 3593408605 !r21 = gg r17 r20 r19 r18 (w!!10) 9 38016083 !r22 = gg r18 r21 r20 r19 (w!!15) 14 3634488961 !r23 = gg r19 r22 r21 r20 (w!!4) 20 3889429448 !r24 = gg r20 r23 r22 r21 (w!!9) 5 568446438 !r25 = gg r21 r24 r23 r22 (w!!14) 9 3275163606 !r26 = gg r22 r25 r24 r23 (w!!3) 14 4107603335 !r27 = gg r23 r26 r25 r24 (w!!8) 20 1163531501 !r28 = gg r24 r27 r26 r25 (w!!13) 5 2850285829 !r29 = gg r25 r28 r27 r26 (w!!2) 9 4243563512 !r30 = gg r26 r29 r28 r27 (w!!7) 14 1735328473 !r31 = gg r27 r30 r29 r28 (w!!12) 20 2368359562 -- Round 3 !r32 = hh r28 r31 r30 r29 (w!!5) 4 4294588738 !r33 = hh r29 r32 r31 r30 (w!!8) 11 2272392833 !r34 = hh r30 r33 r32 r31 (w!!11) 16 1839030562 !r35 = hh r31 r34 r33 r32 (w!!14) 23 4259657740 !r36 = hh r32 r35 r34 r33 (w!!1) 4 2763975236 !r37 = hh r33 r36 r35 r34 (w!!4) 11 1272893353 !r38 = hh r34 r37 r36 r35 (w!!7) 16 4139469664 !r39 = hh r35 r38 r37 r36 (w!!10) 23 3200236656 !r40 = hh r36 r39 r38 r37 (w!!13) 4 681279174 !r41 = hh r37 r40 r39 r38 (w!!0) 11 3936430074 !r42 = hh r38 r41 r40 r39 (w!!3) 16 3572445317 !r43 = hh r39 r42 r41 r40 (w!!6) 23 76029189 !r44 = hh r40 r43 r42 r41 (w!!9) 4 3654602809 !r45 = hh r41 r44 r43 r42 (w!!12) 11 3873151461 !r46 = hh r42 r45 r44 r43 (w!!15) 16 530742520 !r47 = hh r43 r46 r45 r44 (w!!2) 23 3299628645 -- Round 4 !r48 = ii r44 r47 r46 r45 (w!!0) 6 4096336452 !r49 = ii r45 r48 r47 r46 (w!!7) 10 1126891415 !r50 = ii r46 r49 r48 r47 (w!!14) 15 2878612391 !r51 = ii r47 r50 r49 r48 (w!!5) 21 4237533241 !r52 = ii r48 r51 r50 r49 (w!!12) 6 1700485571 !r53 = ii r49 r52 r51 r50 (w!!3) 10 2399980690 !r54 = ii r50 r53 r52 r51 (w!!10) 15 4293915773 !r55 = ii r51 r54 r53 r52 (w!!1) 21 2240044497 !r56 = ii r52 r55 r54 r53 (w!!8) 6 1873313359 !r57 = ii r53 r56 r55 r54 (w!!15) 10 4264355552 !r58 = ii r54 r57 r56 r55 (w!!6) 15 2734768916 !r59 = ii r55 r58 r57 r56 (w!!13) 21 1309151649 !r60 = ii r56 r59 r58 r57 (w!!4) 6 4149444226 !r61 = ii r57 r60 r59 r58 (w!!11) 10 3174756917 !r62 = ii r58 r61 r60 r59 (w!!2) 15 718787259 !r63 = ii r59 r62 r61 r60 (w!!9) 21 3951481745 in MD5Par r60 r63 r62 r61 where f !x !y !z = (x .&. y) .|. ((complement x) .&. z) {-# INLINE f #-} g !x !y !z = (x .&. z) .|. (y .&. (complement z)) {-# INLINE g #-} h !x !y !z = (x `xor` y `xor` z) {-# INLINE h #-} i !x !y !z = y `xor` (x .|. (complement z)) {-# INLINE i #-} ff a b c d x s ac = let !a' = f b c d + x + ac + a !a'' = rotateL a' s in a'' + b {-# INLINE ff #-} gg a b c d x s ac = let !a' = g b c d + x + ac + a !a'' = rotateL a' s in a'' + b {-# INLINE gg #-} hh a b c d x s ac = let !a' = h b c d + x + ac + a !a'' = rotateL a' s in a'' + b {-# INLINE hh #-} ii a b c d x s ac = let !a' = i b c d + x + ac + a !a'' = rotateL a' s in a'' + b {-# INLINE ii #-} (!!) word32s pos = getNthWord pos word32s {-# INLINE (!!) #-} getNthWord n _bs@(PS ptr off _len) = inlinePerformIO $ withForeignPtr ptr $ \ptr' -> do let p = castPtr $ plusPtr ptr' off peekElemOff p n {-# INLINE getNthWord #-} {-# INLINE applyMD5Rounds #-} ----- Some quick and dirty instances follow ----- instance Show MD5Digest where show (MD5Digest h) = show h instance Binary MD5Digest where put (MD5Digest (MD5Ctx p _ _)) = put p get = do p <- get return $ MD5Digest $ MD5Ctx p B.empty 0 instance Ord MD5Digest where compare (MD5Digest (MD5Ctx a _ _)) (MD5Digest (MD5Ctx b _ _)) = compare a b instance Eq MD5Digest where (MD5Digest (MD5Ctx a _ _)) == (MD5Digest (MD5Ctx b _ _)) = a == b instance Show MD5Context where show (MD5Ctx (MD5Par a b c d) _ _) = let bs = runPut $ putWord32be d >> putWord32be c >> putWord32be b >> putWord32be a in foldl' (\str w -> let c = showHex w str in if length c < length str + 2 then '0':c else c) "" (L.unpack bs) instance Binary MD5Context where put (MD5Ctx p r l) = put p >> putWord8 (fromIntegral (B.length r)) >> putByteString r >> putWord64be l get = do p <- get s <- getWord8 r <- getByteString (fromIntegral s) l <- getWord64be return $ MD5Ctx p r l instance Binary MD5Partial where put (MD5Par a b c d) = putWord32be a >> putWord32be b >> putWord32be c >> putWord32be d get = do a <- getWord32be b <- getWord32be c <- getWord32be d <- getWord32be return $ MD5Par a b c d