module Data.Digest.Pure.MD5
(
MD5Context
, MD5Digest
, md5InitialContext
, blockSize
, 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 Data.Word
import Foreign.Storable
import Foreign.Ptr
import Foreign.ForeignPtr
import System.IO
import Data.Binary
import Data.Binary.Get
import Data.Binary.Put
import Numeric
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)
data MD5Context = MD5Ctx { mdPartial :: !MD5Partial,
mdLeftOver :: !ByteString,
mdTotalLen :: !Word64 }
data MD5Digest = MD5Digest MD5Partial deriving (Eq, Ord)
md5InitialContext :: MD5Context
md5InitialContext = MD5Ctx (MD5Par h0 h1 h2 h3) B.empty 0
h0 = 0x67452301
h1 = 0xEFCDAB89
h2 = 0x98BADCFE
h3 = 0x10325476
md5 :: L.ByteString -> MD5Digest
md5 bs = md5Finalize $ md5Update md5InitialContext bs
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 $ mdPartial $ 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)
md5Update :: MD5Context -> L.ByteString -> MD5Context
md5Update !ctx@(MD5Ctx _ !leftover _) bsLazy =
let bs = L.fromChunks (leftover:L.toChunks bsLazy)
in blockAndDo ctx bs
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 = if isAligned blk' then blk' else B.copy blk'
blk' = B.concat $ L.toChunks top
(top,rest) = L.splitAt blockSizeBytesI64 bs
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
}
isAligned (PS _ off _) = off `rem` 4 == 0
applyMD5Rounds :: MD5Partial -> ByteString -> MD5Partial
applyMD5Rounds par@(MD5Par a b c d) w =
let
!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
!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
!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
!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)
g !x !y !z = (x .&. z) .|. (y .&. (complement z))
h !x !y !z = (x `xor` y `xor` z)
i !x !y !z = y `xor` (x .|. (complement z))
ff a b c d !x s ac =
let !a' = f b c d + x + ac + a
!a'' = rotateL a' s
in a'' + b
gg a b c d !x s ac =
let !a' = g b c d + x + ac + a
!a'' = rotateL a' s
in a'' + b
hh a b c d !x s ac =
let !a' = h b c d + x + ac + a
!a'' = rotateL a' s
in a'' + b
ii a b c d !x s ac =
let !a' = i b c d + x + ac + a
!a'' = rotateL a' s
in a'' + b
(!!) word32s pos = getNthWord pos word32s
getNthWord n bs@(PS ptr off len) =
inlinePerformIO $ withForeignPtr ptr $ \ptr' -> do
let p = castPtr $ plusPtr ptr' off
peekElemOff p n
infix 9 .<.
(.<.) :: Word8 -> Int -> Word32
(.<.) w i = (fromIntegral w) `shiftL` i
instance Show MD5Digest where
show (MD5Digest h) = show h
instance Binary MD5Digest where
put (MD5Digest p) = put p
get = do
p <- get
return $ MD5Digest p
instance Show MD5Partial where
show (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) = putWord32le a >> putWord32le b >> putWord32le c >> putWord32le d
get = do a <- getWord32le
b <- getWord32le
c <- getWord32le
d <- getWord32le
return $ MD5Par a b c d