cryptonite/Crypto/PubKey/ECC/P256.hs
2015-05-02 14:50:11 +01:00

143 lines
5.2 KiB
Haskell

-- |
-- Module : Crypto.PubKey.ECC.P256
-- License : BSD-style
-- Maintainer : Vincent Hanquez <vincent@snarc.org>
-- Stability : experimental
-- Portability : unknown
--
-- P256 support
--
{-# LANGUAGE GeneralizedNewtypeDeriving #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE BangPatterns #-}
{-# LANGUAGE EmptyDataDecls #-}
{-# OPTIONS_GHC -fno-warn-unused-binds #-}
{-# OPTIONS_GHC -fno-warn-unused-matches #-}
{-# OPTIONS_GHC -fno-warn-unused-imports #-}
module Crypto.PubKey.ECC.P256
( Scalar
, Point
) where
import Data.Word
import Foreign.Ptr
import Foreign.C.Types
import Crypto.Internal.Compat
import Crypto.Internal.Imports
import Crypto.Internal.Memory
import Crypto.Internal.ByteArray
import qualified Crypto.Internal.ByteArray as B
import Crypto.Error
-- | A P256 scalar
newtype Scalar = Scalar SecureBytes
deriving (Eq,ByteArrayAccess)
-- | A P256 point
data Point = Point !Bytes !Bytes
deriving (Show,Eq)
publicKeySize :: Int
publicKeySize = 32
secretKeySize :: Int
secretKeySize = 32
type P256Digit = Word32
data P256Scalar
data P256Y
data P256X
------------------------------------------------------------------------
-- Point methods
------------------------------------------------------------------------
toPoint :: Scalar -> Point
toPoint s = withNewPoint $ \px py -> withScalar s $ \p ->
ccryptonite_p256_basepoint_mul p px py
------------------------------------------------------------------------
-- Scalar methods
------------------------------------------------------------------------
scalarZero :: Scalar
scalarZero = withNewScalarFreeze $ \d -> ccryptonite_p256_init d
scalarAdd :: Scalar -> Scalar -> Scalar
scalarAdd a b =
withNewScalarFreeze $ \d -> withScalar a $ \pa -> withScalar b $ \pb ->
void $ ccryptonite_p256_add pa pb d
scalarSub :: Scalar -> Scalar -> Scalar
scalarSub a b =
withNewScalarFreeze $ \d -> withScalar a $ \pa -> withScalar b $ \pb ->
void $ ccryptonite_p256_sub pa pb d
scalarCmp :: Scalar -> Scalar -> Ordering
scalarCmp a b = unsafeDoIO $
withScalar a $ \pa -> withScalar b $ \pb -> do
v <- ccryptonite_p256_cmp pa pb
return $ compare v 0
------------------------------------------------------------------------
-- Memory Helpers
------------------------------------------------------------------------
withNewPoint :: (Ptr P256X -> Ptr P256Y -> IO ()) -> Point
withNewPoint f = unsafeDoIO $ do
(x,y) <- B.allocRet pointCoordSize $ \py -> B.alloc pointCoordSize $ \px -> f px py
return $! Point x y
where pointCoordSize = 32
{-# NOINLINE withNewPoint #-}
withPoint :: Point -> (Ptr P256X -> Ptr P256Y -> IO a) -> IO a
withPoint (Point x y) f = B.withByteArray x $ \px -> B.withByteArray y $ \py -> f px py
withNewScalarFreeze :: (Ptr P256Scalar -> IO ()) -> Scalar
withNewScalarFreeze f = Scalar $ B.allocAndFreeze scalarSize f
where scalarSize = 32
{-# NOINLINE withNewScalarFreeze #-}
withScalar :: Scalar -> (Ptr P256Scalar -> IO a) -> IO a
withScalar (Scalar d) f = B.withByteArray d f
------------------------------------------------------------------------
-- Foreign bindings
------------------------------------------------------------------------
foreign import ccall "cryptonite_p256_init"
ccryptonite_p256_init :: Ptr P256Scalar -> IO ()
foreign import ccall "cryptonite_p256_clear"
ccryptonite_p256_clear :: Ptr P256Scalar -> IO ()
foreign import ccall "cryptonite_p256_add"
ccryptonite_p256_add :: Ptr P256Scalar -> Ptr P256Scalar -> Ptr P256Scalar -> IO CInt
foreign import ccall "cryptonite_p256_sub"
ccryptonite_p256_sub :: Ptr P256Scalar -> Ptr P256Scalar -> Ptr P256Scalar -> IO CInt
foreign import ccall "cryptonite_p256_cmp"
ccryptonite_p256_cmp :: Ptr P256Scalar -> Ptr P256Scalar -> IO CInt
foreign import ccall "cryptonite_p256_mod"
ccryptonite_p256_mod :: Ptr P256Scalar -> Ptr P256Scalar -> Ptr P256Scalar -> IO ()
foreign import ccall "cryptonite_p256_modmul"
ccryptonite_p256_modmul :: Ptr P256Scalar -> Ptr P256Scalar -> P256Digit -> Ptr P256Scalar -> Ptr P256Scalar -> IO ()
foreign import ccall "cryptonite_p256_modinv"
ccryptonite_p256_modinv :: Ptr P256Scalar -> Ptr P256Scalar -> Ptr P256Scalar -> IO ()
foreign import ccall "cryptonite_p256_modinv_vartime"
ccryptonite_p256_modinv_vartime :: Ptr P256Scalar -> Ptr P256Scalar -> Ptr P256Scalar -> IO ()
foreign import ccall "cryptonite_p256_base_point_mul"
ccryptonite_p256_basepoint_mul :: Ptr P256Scalar
-> Ptr P256X -> Ptr P256Y
-> IO ()
foreign import ccall "cryptonite_p256_point_mul"
ccryptonite_p256_point_mul :: Ptr P256Scalar
-> Ptr P256Scalar -> Ptr P256Scalar
-> Ptr P256Scalar -> Ptr P256Scalar
-> IO ()
foreign import ccall "cryptonite_p256_is_valid_point"
ccryptonite_p256_is_valid_point :: Ptr P256Scalar -> Ptr P256Scalar -> IO CInt
foreign import ccall "cryptonite_p256_to_bin"
ccryptonite_p256_to_bin :: Ptr P256Scalar -> Ptr Word8 -> IO ()
foreign import ccall "cryptonite_p256_from_bin"
ccryptonite_p256_from_bin :: Ptr Word8 -> Ptr P256Scalar -> IO ()