{-# LANGUAGE DeriveDataTypeable #-}
module Crypto.Cipher.ChaChaPoly1305.Conduit
( encrypt
, decrypt
, ChaChaException (..)
) where
import Control.Exception (assert)
import Control.Monad.Catch (Exception, MonadThrow, throwM)
import qualified Crypto.Cipher.ChaChaPoly1305 as Cha
import qualified Crypto.Error as CE
import qualified Crypto.MAC.Poly1305 as Poly1305
import qualified Data.ByteArray as BA
import Data.ByteString (ByteString)
import qualified Data.ByteString as B
import qualified Data.ByteString.Lazy as BL
import Data.Conduit (ConduitM, await, leftover, yield)
import qualified Data.Conduit.Binary as CB
import Data.Typeable (Typeable)
cf :: MonadThrow m
=> (CE.CryptoError -> ChaChaException)
-> CE.CryptoFailable a
-> m a
cf :: (CryptoError -> ChaChaException) -> CryptoFailable a -> m a
cf _ (CE.CryptoPassed x :: a
x) = a -> m a
forall (m :: * -> *) a. Monad m => a -> m a
return a
x
cf f :: CryptoError -> ChaChaException
f (CE.CryptoFailed e :: CryptoError
e) = ChaChaException -> m a
forall (m :: * -> *) e a. (MonadThrow m, Exception e) => e -> m a
throwM (CryptoError -> ChaChaException
f CryptoError
e)
data ChaChaException
= EncryptNonceException !CE.CryptoError
| EncryptKeyException !CE.CryptoError
| DecryptNonceException !CE.CryptoError
| DecryptKeyException !CE.CryptoError
| MismatchedAuth
deriving (Int -> ChaChaException -> ShowS
[ChaChaException] -> ShowS
ChaChaException -> String
(Int -> ChaChaException -> ShowS)
-> (ChaChaException -> String)
-> ([ChaChaException] -> ShowS)
-> Show ChaChaException
forall a.
(Int -> a -> ShowS) -> (a -> String) -> ([a] -> ShowS) -> Show a
showList :: [ChaChaException] -> ShowS
$cshowList :: [ChaChaException] -> ShowS
show :: ChaChaException -> String
$cshow :: ChaChaException -> String
showsPrec :: Int -> ChaChaException -> ShowS
$cshowsPrec :: Int -> ChaChaException -> ShowS
Show, Typeable)
instance Exception ChaChaException
encrypt
:: MonadThrow m
=> ByteString
-> ByteString
-> ConduitM ByteString ByteString m ()
encrypt :: ByteString -> ByteString -> ConduitM ByteString ByteString m ()
encrypt nonceBS :: ByteString
nonceBS key :: ByteString
key = do
Nonce
nonce <- (CryptoError -> ChaChaException)
-> CryptoFailable Nonce -> ConduitT ByteString ByteString m Nonce
forall (m :: * -> *) a.
MonadThrow m =>
(CryptoError -> ChaChaException) -> CryptoFailable a -> m a
cf CryptoError -> ChaChaException
EncryptNonceException (CryptoFailable Nonce -> ConduitT ByteString ByteString m Nonce)
-> CryptoFailable Nonce -> ConduitT ByteString ByteString m Nonce
forall a b. (a -> b) -> a -> b
$ ByteString -> CryptoFailable Nonce
forall iv. ByteArrayAccess iv => iv -> CryptoFailable Nonce
Cha.nonce12 ByteString
nonceBS
State
state0 <- (CryptoError -> ChaChaException)
-> CryptoFailable State -> ConduitT ByteString ByteString m State
forall (m :: * -> *) a.
MonadThrow m =>
(CryptoError -> ChaChaException) -> CryptoFailable a -> m a
cf CryptoError -> ChaChaException
EncryptKeyException (CryptoFailable State -> ConduitT ByteString ByteString m State)
-> CryptoFailable State -> ConduitT ByteString ByteString m State
forall a b. (a -> b) -> a -> b
$ ByteString -> Nonce -> CryptoFailable State
forall key.
ByteArrayAccess key =>
key -> Nonce -> CryptoFailable State
Cha.initialize ByteString
key Nonce
nonce
ByteString -> ConduitM ByteString ByteString m ()
forall (m :: * -> *) o i. Monad m => o -> ConduitT i o m ()
yield ByteString
nonceBS
let loop :: State -> ConduitT o o m ()
loop state1 :: State
state1 = do
Maybe o
mbs <- ConduitT o o m (Maybe o)
forall (m :: * -> *) i. Monad m => Consumer i m (Maybe i)
await
case Maybe o
mbs of
Nothing -> o -> ConduitT o o m ()
forall (m :: * -> *) o i. Monad m => o -> ConduitT i o m ()
yield (o -> ConduitT o o m ()) -> o -> ConduitT o o m ()
forall a b. (a -> b) -> a -> b
$ Auth -> o
forall bin bout.
(ByteArrayAccess bin, ByteArray bout) =>
bin -> bout
BA.convert (Auth -> o) -> Auth -> o
forall a b. (a -> b) -> a -> b
$ State -> Auth
Cha.finalize State
state1
Just bs :: o
bs -> do
let (bs' :: o
bs', state2 :: State
state2) = o -> State -> (o, State)
forall ba. ByteArray ba => ba -> State -> (ba, State)
Cha.encrypt o
bs State
state1
o -> ConduitT o o m ()
forall (m :: * -> *) o i. Monad m => o -> ConduitT i o m ()
yield o
bs'
State -> ConduitT o o m ()
loop State
state2
State -> ConduitM ByteString ByteString m ()
forall (m :: * -> *) o.
(Monad m, ByteArray o) =>
State -> ConduitT o o m ()
loop (State -> ConduitM ByteString ByteString m ())
-> State -> ConduitM ByteString ByteString m ()
forall a b. (a -> b) -> a -> b
$ State -> State
Cha.finalizeAAD State
state0
decrypt
:: MonadThrow m
=> ByteString
-> ConduitM ByteString ByteString m ()
decrypt :: ByteString -> ConduitM ByteString ByteString m ()
decrypt key :: ByteString
key = do
ByteString
nonceBS <- Int -> ConduitT ByteString ByteString m ByteString
forall (m :: * -> *) o.
Monad m =>
Int -> ConduitT ByteString o m ByteString
CB.take 12
Nonce
nonce <- (CryptoError -> ChaChaException)
-> CryptoFailable Nonce -> ConduitT ByteString ByteString m Nonce
forall (m :: * -> *) a.
MonadThrow m =>
(CryptoError -> ChaChaException) -> CryptoFailable a -> m a
cf CryptoError -> ChaChaException
DecryptNonceException (CryptoFailable Nonce -> ConduitT ByteString ByteString m Nonce)
-> CryptoFailable Nonce -> ConduitT ByteString ByteString m Nonce
forall a b. (a -> b) -> a -> b
$ ByteString -> CryptoFailable Nonce
forall iv. ByteArrayAccess iv => iv -> CryptoFailable Nonce
Cha.nonce12 (ByteString -> CryptoFailable Nonce)
-> ByteString -> CryptoFailable Nonce
forall a b. (a -> b) -> a -> b
$ ByteString -> ByteString
BL.toStrict ByteString
nonceBS
State
state0 <- (CryptoError -> ChaChaException)
-> CryptoFailable State -> ConduitT ByteString ByteString m State
forall (m :: * -> *) a.
MonadThrow m =>
(CryptoError -> ChaChaException) -> CryptoFailable a -> m a
cf CryptoError -> ChaChaException
DecryptKeyException (CryptoFailable State -> ConduitT ByteString ByteString m State)
-> CryptoFailable State -> ConduitT ByteString ByteString m State
forall a b. (a -> b) -> a -> b
$ ByteString -> Nonce -> CryptoFailable State
forall key.
ByteArrayAccess key =>
key -> Nonce -> CryptoFailable State
Cha.initialize ByteString
key Nonce
nonce
let loop :: State -> ConduitT ByteString ByteString m ()
loop state1 :: State
state1 = do
Either ByteString ByteString
ebs <- (ByteString -> ByteString)
-> ConduitT ByteString ByteString m (Either ByteString ByteString)
forall (m :: * -> *) o.
Monad m =>
(ByteString -> ByteString)
-> ConduitT ByteString o m (Either ByteString ByteString)
awaitExcept16 ByteString -> ByteString
forall a. a -> a
id
case Either ByteString ByteString
ebs of
Left final :: ByteString
final ->
case ByteString -> CryptoFailable Auth
forall b. ByteArrayAccess b => b -> CryptoFailable Auth
Poly1305.authTag ByteString
final of
CE.CryptoPassed final' :: Auth
final' | State -> Auth
Cha.finalize State
state1 Auth -> Auth -> Bool
forall a. Eq a => a -> a -> Bool
== Auth
final' -> () -> ConduitT ByteString ByteString m ()
forall (m :: * -> *) a. Monad m => a -> m a
return ()
_ -> ChaChaException -> ConduitT ByteString ByteString m ()
forall (m :: * -> *) e a. (MonadThrow m, Exception e) => e -> m a
throwM ChaChaException
MismatchedAuth
Right bs :: ByteString
bs -> do
let (bs' :: ByteString
bs', state2 :: State
state2) = ByteString -> State -> (ByteString, State)
forall ba. ByteArray ba => ba -> State -> (ba, State)
Cha.decrypt ByteString
bs State
state1
ByteString -> ConduitT ByteString ByteString m ()
forall (m :: * -> *) o i. Monad m => o -> ConduitT i o m ()
yield ByteString
bs'
State -> ConduitT ByteString ByteString m ()
loop State
state2
State -> ConduitM ByteString ByteString m ()
forall (m :: * -> *).
MonadThrow m =>
State -> ConduitT ByteString ByteString m ()
loop (State -> ConduitM ByteString ByteString m ())
-> State -> ConduitM ByteString ByteString m ()
forall a b. (a -> b) -> a -> b
$ State -> State
Cha.finalizeAAD State
state0
where
awaitExcept16 :: (ByteString -> ByteString)
-> ConduitT ByteString o m (Either ByteString ByteString)
awaitExcept16 front :: ByteString -> ByteString
front = do
Maybe ByteString
mbs <- ConduitT ByteString o m (Maybe ByteString)
forall (m :: * -> *) i. Monad m => Consumer i m (Maybe i)
await
case Maybe ByteString
mbs of
Nothing -> Either ByteString ByteString
-> ConduitT ByteString o m (Either ByteString ByteString)
forall (m :: * -> *) a. Monad m => a -> m a
return (Either ByteString ByteString
-> ConduitT ByteString o m (Either ByteString ByteString))
-> Either ByteString ByteString
-> ConduitT ByteString o m (Either ByteString ByteString)
forall a b. (a -> b) -> a -> b
$ ByteString -> Either ByteString ByteString
forall a b. a -> Either a b
Left (ByteString -> Either ByteString ByteString)
-> ByteString -> Either ByteString ByteString
forall a b. (a -> b) -> a -> b
$ ByteString -> ByteString
front ByteString
B.empty
Just bs :: ByteString
bs -> do
let bs' :: ByteString
bs' = ByteString -> ByteString
front ByteString
bs
if ByteString -> Int
B.length ByteString
bs' Int -> Int -> Bool
forall a. Ord a => a -> a -> Bool
> 16
then do
let (x :: ByteString
x, y :: ByteString
y) = Int -> ByteString -> (ByteString, ByteString)
B.splitAt (ByteString -> Int
B.length ByteString
bs' Int -> Int -> Int
forall a. Num a => a -> a -> a
- 16) ByteString
bs'
Bool
-> (ByteString -> ConduitT ByteString o m ())
-> ByteString
-> ConduitT ByteString o m ()
forall a. (?callStack::CallStack) => Bool -> a -> a
assert (ByteString -> Int
B.length ByteString
y Int -> Int -> Bool
forall a. Eq a => a -> a -> Bool
== 16) ByteString -> ConduitT ByteString o m ()
forall i o (m :: * -> *). i -> ConduitT i o m ()
leftover ByteString
y
Either ByteString ByteString
-> ConduitT ByteString o m (Either ByteString ByteString)
forall (m :: * -> *) a. Monad m => a -> m a
return (Either ByteString ByteString
-> ConduitT ByteString o m (Either ByteString ByteString))
-> Either ByteString ByteString
-> ConduitT ByteString o m (Either ByteString ByteString)
forall a b. (a -> b) -> a -> b
$ ByteString -> Either ByteString ByteString
forall a b. b -> Either a b
Right ByteString
x
else (ByteString -> ByteString)
-> ConduitT ByteString o m (Either ByteString ByteString)
awaitExcept16 (ByteString -> ByteString -> ByteString
B.append ByteString
bs')