-- |
-- Module : Crypto.Cipher.Types.Modes
-- License : BSD-style
-- Maintainer : Vincent Hanquez <vincent@snarc.org>
-- Stability : Stable
-- Portability : Excellent
--
-- block cipher modes immutable interfaces
--
module Crypto.Cipher.Types.OfIO
(
-- * ECB
ecbEncryptOfIO
, ecbDecryptOfIO
{-
-- * CBC
, cbcEncryptOfIO
, cbcDecryptOfIO
-- * CFB
, cfbEncryptOfIO
, cfbDecryptOfIO
, cfb8EncryptOfIO
, cfb8DecryptOfIO
-- * CTR
, ctrCombineOfIO
-- * XTS
, xtsEncryptOfIO
, xtsDecryptOfIO
-}
) where
import Data.ByteString (ByteString)
import qualified Data.ByteString as B
import qualified Data.ByteString.Internal as B
import Data.Byteable
--import Crypto.Cipher.Types.Base
import Crypto.Cipher.Types.Block
import Crypto.Cipher.Types.BlockIO
--import Foreign.Storable (poke)
--import Foreign.Ptr
isBlockSized :: (BlockCipher cipher, BlockCipherIO cipher) => cipher -> Int -> Bool
isBlockSized cipher bsLen = (bsLen `mod` blockSize cipher) == 0
notBlockSized :: (BlockCipher cipher, BlockCipherIO cipher) => cipher -> a
notBlockSized = undefined
withDest :: BlockCipherIO cipher
=> cipher
-> ByteString
-> (PtrDest -> PtrSource -> BufferLength -> IO ())
-> ByteString
withDest cipher bs f
| B.null bs = B.empty
| not (isBlockSized cipher len) = notBlockSized cipher
| otherwise =
B.unsafeCreate len $ \dst ->
withBytePtr bs $ \src ->
f dst src (fromIntegral len)
where len = B.length bs
{-
withDestIV :: BlockCipherIO cipher
=> cipher
-> IV cipher
-> ByteString
-> (PtrIV -> PtrDest -> PtrSource -> BufferLength -> IO ())
-> ByteString
withDestIV cipher (IV iv) bs f
| B.null bs = B.empty
| not (isBlockSized cipher len) = notBlockSized cipher
| otherwise =
B.unsafeCreate len $ \dst ->
withBytePtr iv $ \ivPtr ->
withBytePtr bs $ \src ->
f ivPtr dst src (fromIntegral len)
where len = B.length bs
withDestIVAnySize :: BlockCipherIO cipher
=> IV cipher
-> ByteString
-> (PtrIV -> PtrDest -> PtrSource -> BufferLength -> IO ())
-> ByteString
withDestIVAnySize (IV iv) bs f
| B.null bs = B.empty
| otherwise =
B.unsafeCreate len $ \dst ->
withBytePtr iv $ \ivPtr ->
withBytePtr bs $ \src ->
f ivPtr dst src (fromIntegral len)
where len = B.length bs
-}
-- | Encrypt using the ECB mode.
--
-- input need to be a multiple of the blocksize
ecbEncryptOfIO :: BlockCipherIO cipher => cipher -> ByteString -> ByteString
ecbEncryptOfIO cipher bs = withDest cipher bs $ ecbEncryptMutable cipher
-- | Decrypt using the ECB mode.
--
-- input need to be a multiple of the blocksize
ecbDecryptOfIO :: BlockCipherIO cipher => cipher -> ByteString -> ByteString
ecbDecryptOfIO cipher bs = withDest cipher bs $ ecbEncryptMutable cipher
{-
-- | encrypt using the CBC mode.
--
-- input need to be a multiple of the blocksize
cbcEncryptOfIO :: BlockCipherIO cipher => cipher -> IV cipher -> ByteString -> ByteString
cbcEncryptOfIO cipher iv bs = withDestIV cipher iv bs $ cbcEncryptMutable cipher
-- | decrypt using the CBC mode.
--
-- input need to be a multiple of the blocksize
cbcDecryptOfIO :: BlockCipherIO cipher => cipher -> IV cipher -> ByteString -> ByteString
cbcDecryptOfIO cipher iv bs = withDestIV cipher iv bs $ cbcDecryptMutable cipher
-- | encrypt using the CFB mode.
--
-- input need to be a multiple of the blocksize
cfbEncryptOfIO :: BlockCipherIO cipher => cipher -> IV cipher -> ByteString -> ByteString
cfbEncryptOfIO cipher iv bs = withDestIV cipher iv bs $ cfbEncryptMutable cipher
-- | decrypt using the CFB mode.
--
-- input need to be a multiple of the blocksize
cfbDecryptOfIO :: BlockCipherIO cipher => cipher -> IV cipher -> ByteString -> ByteString
cfbDecryptOfIO cipher iv bs = withDestIV cipher iv bs $ cfbDecryptMutable cipher
-- | combine using the CTR mode.
--
-- CTR mode produce a stream of randomized data that is combined
-- (by XOR operation) with the input stream.
--
-- encryption and decryption are the same operation.
--
-- input can be of any size
ctrCombineOfIO :: BlockCipherIO cipher => cipher -> IV cipher -> ByteString -> ByteString
ctrCombineOfIO cipher iv bs = withDestIVAnySize iv bs $ cfbDecryptMutable cipher
-- | encrypt using the XTS mode.
--
-- input need to be a multiple of the blocksize
xtsEncryptOfIO :: BlockCipherIO cipher => (cipher, cipher) -> IV cipher -> DataUnitOffset -> ByteString -> ByteString
xtsEncryptOfIO ciphers@(c1,_) iv ofs bs = withDestIV c1 iv bs $ \ivPtr -> xtsEncryptMutable ciphers ivPtr ofs
-- | decrypt using the XTS mode.
--
-- input need to be a multiple of the blocksize
xtsDecryptOfIO :: BlockCipherIO cipher => (cipher, cipher) -> IV cipher -> DataUnitOffset -> ByteString -> ByteString
xtsDecryptOfIO ciphers@(c1,_) iv ofs bs = withDestIV c1 iv bs $ \ivPtr -> xtsDecryptMutable ciphers ivPtr ofs
-- | Encrypt using CFB mode in 8 bit output
--
-- Effectively turn a Block cipher in CFB mode into a Stream cipher
cfb8EncryptOfIO :: BlockCipherIO a => a -> IV a -> B.ByteString -> B.ByteString
cfb8EncryptOfIO ctx origIv msg = B.unsafeCreate (B.length msg) $ \dst -> loop dst origIv msg
where loop d iv@(IV i) m
| B.null m = return ()
| otherwise = poke d out >> loop (d `plusPtr` 1) ni (B.drop 1 m)
where m' = if B.length m < blockSize ctx
then m `B.append` B.replicate (blockSize ctx - B.length m) 0
else B.take (blockSize ctx) m
r = cfbEncryptOfIO ctx iv m'
out = B.head r
ni = IV (B.drop 1 i `B.snoc` out)
-- | Decrypt using CFB mode in 8 bit output
--
-- Effectively turn a Block cipher in CFB mode into a Stream cipher
cfb8DecryptOfIO :: BlockCipherIO a => a -> IV a -> B.ByteString -> B.ByteString
cfb8DecryptOfIO ctx origIv msg = B.unsafeCreate (B.length msg) $ \dst -> loop dst origIv msg
where loop d iv@(IV i) m
| B.null m = return ()
| otherwise = poke d out >> loop (d `plusPtr` 1) ni (B.drop 1 m)
where m' = if B.length m < blockSize ctx
then m `B.append` B.replicate (blockSize ctx - B.length m) 0
else B.take (blockSize ctx) m
r = cfbDecryptOfIO ctx iv m'
out = B.head r
ni = IV (B.drop 1 i `B.snoc` B.head m')
-}