-- |
-- Module : Crypto.Hash.SHAKE
-- License : BSD-style
-- Maintainer : Vincent Hanquez <vincent@snarc.org>
-- Stability : experimental
-- Portability : unknown
--
-- module containing the binding functions to work with the
-- SHA3 extendable output functions (SHAKE).
--
{-# LANGUAGE ForeignFunctionInterface #-}
{-# LANGUAGE DeriveDataTypeable #-}
{-# LANGUAGE KindSignatures #-}
{-# LANGUAGE DataKinds #-}
{-# LANGUAGE ConstraintKinds #-}
{-# LANGUAGE ScopedTypeVariables #-}
{-# LANGUAGE TypeOperators #-}
{-# LANGUAGE TypeFamilies #-}
{-# LANGUAGE UndecidableInstances #-}
module Crypto.Hash.SHAKE
( SHAKE128 (..), SHAKE256 (..)
) where
import Crypto.Hash.Types
import Foreign.Ptr (Ptr)
import Data.Typeable
import Data.Word (Word8, Word32)
import Data.Proxy (Proxy(..))
import GHC.TypeLits (Nat, KnownNat, natVal)
import Crypto.Internal.Nat
-- | SHAKE128 (128 bits) extendable output function. Supports an arbitrary
-- digest size (multiple of 8 bits), to be specified as a type parameter
-- of kind 'Nat'.
--
-- Note: outputs from @'SHAKE128' n@ and @'SHAKE128' m@ for the same input are
-- correlated (one being a prefix of the other). Results are unrelated to
-- 'SHAKE256' results.
data SHAKE128 (bitlen :: Nat) = SHAKE128
deriving (Show, Typeable)
instance (IsDivisibleBy8 bitlen, KnownNat bitlen) => HashAlgorithm (SHAKE128 bitlen) where
type HashBlockSize (SHAKE128 bitlen) = 168
type HashDigestSize (SHAKE128 bitlen) = Div8 bitlen
type HashInternalContextSize (SHAKE128 bitlen) = 376
hashBlockSize _ = 168
hashDigestSize _ = byteLen (Proxy :: Proxy bitlen)
hashInternalContextSize _ = 376
hashInternalInit p = c_sha3_init p 128
hashInternalUpdate = c_sha3_update
hashInternalFinalize = shakeFinalizeOutput (Proxy :: Proxy bitlen)
-- | SHAKE256 (256 bits) extendable output function. Supports an arbitrary
-- digest size (multiple of 8 bits), to be specified as a type parameter
-- of kind 'Nat'.
--
-- Note: outputs from @'SHAKE256' n@ and @'SHAKE256' m@ for the same input are
-- correlated (one being a prefix of the other). Results are unrelated to
-- 'SHAKE128' results.
data SHAKE256 (bitlen :: Nat) = SHAKE256
deriving (Show, Typeable)
instance (IsDivisibleBy8 bitlen, KnownNat bitlen) => HashAlgorithm (SHAKE256 bitlen) where
type HashBlockSize (SHAKE256 bitlen) = 136
type HashDigestSize (SHAKE256 bitlen) = Div8 bitlen
type HashInternalContextSize (SHAKE256 bitlen) = 344
hashBlockSize _ = 136
hashDigestSize _ = byteLen (Proxy :: Proxy bitlen)
hashInternalContextSize _ = 344
hashInternalInit p = c_sha3_init p 256
hashInternalUpdate = c_sha3_update
hashInternalFinalize = shakeFinalizeOutput (Proxy :: Proxy bitlen)
shakeFinalizeOutput :: (IsDivisibleBy8 bitlen, KnownNat bitlen)
=> proxy bitlen
-> Ptr (Context a)
-> Ptr (Digest a)
-> IO ()
shakeFinalizeOutput d ctx dig = do
c_sha3_finalize_shake ctx
c_sha3_output ctx dig (byteLen d)
foreign import ccall unsafe "cryptonite_sha3_init"
c_sha3_init :: Ptr (Context a) -> Word32 -> IO ()
foreign import ccall "cryptonite_sha3_update"
c_sha3_update :: Ptr (Context a) -> Ptr Word8 -> Word32 -> IO ()
foreign import ccall unsafe "cryptonite_sha3_finalize_shake"
c_sha3_finalize_shake :: Ptr (Context a) -> IO ()
foreign import ccall unsafe "cryptonite_sha3_output"
c_sha3_output :: Ptr (Context a) -> Ptr (Digest a) -> Word32 -> IO ()