{-# LANGUAGE CPP #-}
-- |
-- Module      : Network.TLS.Record.Reading
-- License     : BSD-style
-- Maintainer  : Vincent Hanquez <vincent@snarc.org>
-- Stability   : experimental
-- Portability : unknown
--
-- TLS record layer in Rx direction
--
module Network.TLS.Record.Reading
    ( recvRecord
    , recvRecord13
    ) where

import Control.Monad.Reader
import qualified Data.ByteString as B

import Network.TLS.Context.Internal
import Network.TLS.ErrT
import Network.TLS.Hooks
import Network.TLS.Imports
import Network.TLS.Packet
import Network.TLS.Record
import Network.TLS.Struct

----------------------------------------------------------------

exceeds :: Integral ty => Context -> Int -> ty -> Bool
exceeds :: forall ty. Integral ty => Context -> Int -> ty -> Bool
exceeds Context
ctx Int
overhead ty
actual =
    case Context -> Maybe Int
ctxFragmentSize Context
ctx of
        Maybe Int
Nothing -> Bool
False
        Just Int
sz -> forall a b. (Integral a, Num b) => a -> b
fromIntegral ty
actual forall a. Ord a => a -> a -> Bool
> Int
sz forall a. Num a => a -> a -> a
+ Int
overhead

getRecord :: Context -> Int -> Header -> ByteString -> IO (Either TLSError (Record Plaintext))
getRecord :: Context
-> Int
-> Header
-> ByteString
-> IO (Either TLSError (Record Plaintext))
getRecord Context
ctx Int
appDataOverhead header :: Header
header@(Header ProtocolType
pt Version
_ Word16
_) ByteString
content = do
    Context -> (Logging -> IO ()) -> IO ()
withLog Context
ctx forall a b. (a -> b) -> a -> b
$ \Logging
logging -> Logging -> Header -> ByteString -> IO ()
loggingIORecv Logging
logging Header
header ByteString
content
    forall a. Context -> RecordM a -> IO (Either TLSError a)
runRxState Context
ctx forall a b. (a -> b) -> a -> b
$ do
        Record Plaintext
r <- Header -> ByteString -> RecordM (Record Plaintext)
decodeRecordM Header
header ByteString
content
        let Record ProtocolType
_ Version
_ Fragment Plaintext
fragment = Record Plaintext
r
        forall (f :: * -> *). Applicative f => Bool -> f () -> f ()
when (forall ty. Integral ty => Context -> Int -> ty -> Bool
exceeds Context
ctx Int
overhead forall a b. (a -> b) -> a -> b
$ ByteString -> Int
B.length (forall a. Fragment a -> ByteString
fragmentGetBytes Fragment Plaintext
fragment)) forall a b. (a -> b) -> a -> b
$
            forall e (m :: * -> *) a. MonadError e m => e -> m a
throwError TLSError
contentSizeExceeded
        forall (m :: * -> *) a. Monad m => a -> m a
return Record Plaintext
r
  where overhead :: Int
overhead = if ProtocolType
pt forall a. Eq a => a -> a -> Bool
== ProtocolType
ProtocolType_AppData then Int
appDataOverhead else Int
0

decodeRecordM :: Header -> ByteString -> RecordM (Record Plaintext)
decodeRecordM :: Header -> ByteString -> RecordM (Record Plaintext)
decodeRecordM Header
header ByteString
content = Record Ciphertext -> RecordM (Record Plaintext)
disengageRecord Record Ciphertext
erecord
   where
     erecord :: Record Ciphertext
erecord = forall a. Header -> Fragment a -> Record a
rawToRecord Header
header (ByteString -> Fragment Ciphertext
fragmentCiphertext ByteString
content)

contentSizeExceeded :: TLSError
contentSizeExceeded :: TLSError
contentSizeExceeded = String -> AlertDescription -> TLSError
Error_Protocol String
"record content exceeding maximum size" AlertDescription
RecordOverflow

----------------------------------------------------------------

-- | recvRecord receive a full TLS record (header + data), from the other side.
--
-- The record is disengaged from the record layer
recvRecord :: Context -- ^ TLS context
           -> Bool    -- ^ flag to enable SSLv2 compat ClientHello reception
           -> Int     -- ^ number of AppData bytes to accept above normal maximum size
           -> IO (Either TLSError (Record Plaintext))
recvRecord :: Context -> Bool -> Int -> IO (Either TLSError (Record Plaintext))
recvRecord Context
ctx Bool
compatSSLv2 Int
appDataOverhead
#ifdef SSLV2_COMPATIBLE
    | Bool
compatSSLv2 = Context -> Int -> IO (Either TLSError ByteString)
readExactBytes Context
ctx Int
2 forall (m :: * -> *) a b. Monad m => m a -> (a -> m b) -> m b
>>= forall a c b. (a -> c) -> (b -> c) -> Either a b -> c
either (forall (m :: * -> *) a. Monad m => a -> m a
return forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall a b. a -> Either a b
Left) ByteString -> IO (Either TLSError (Record Plaintext))
sslv2Header
#endif
    | Bool
otherwise = Context -> Int -> IO (Either TLSError ByteString)
readExactBytes Context
ctx Int
5 forall (m :: * -> *) a b. Monad m => m a -> (a -> m b) -> m b
>>= forall a c b. (a -> c) -> (b -> c) -> Either a b -> c
either (forall (m :: * -> *) a. Monad m => a -> m a
return forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall a b. a -> Either a b
Left) (Either TLSError Header -> IO (Either TLSError (Record Plaintext))
recvLengthE forall b c a. (b -> c) -> (a -> b) -> a -> c
. ByteString -> Either TLSError Header
decodeHeader)

        where recvLengthE :: Either TLSError Header -> IO (Either TLSError (Record Plaintext))
recvLengthE = forall a c b. (a -> c) -> (b -> c) -> Either a b -> c
either (forall (m :: * -> *) a. Monad m => a -> m a
return forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall a b. a -> Either a b
Left) Header -> IO (Either TLSError (Record Plaintext))
recvLength

              recvLength :: Header -> IO (Either TLSError (Record Plaintext))
recvLength header :: Header
header@(Header ProtocolType
_ Version
_ Word16
readlen)
                | forall ty. Integral ty => Context -> Int -> ty -> Bool
exceeds Context
ctx Int
2048 Word16
readlen = forall (m :: * -> *) a. Monad m => a -> m a
return forall a b. (a -> b) -> a -> b
$ forall a b. a -> Either a b
Left TLSError
maximumSizeExceeded
                | Bool
otherwise                =
                    Context -> Int -> IO (Either TLSError ByteString)
readExactBytes Context
ctx (forall a b. (Integral a, Num b) => a -> b
fromIntegral Word16
readlen) forall (m :: * -> *) a b. Monad m => m a -> (a -> m b) -> m b
>>=
                        forall a c b. (a -> c) -> (b -> c) -> Either a b -> c
either (forall (m :: * -> *) a. Monad m => a -> m a
return forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall a b. a -> Either a b
Left) (Context
-> Int
-> Header
-> ByteString
-> IO (Either TLSError (Record Plaintext))
getRecord Context
ctx Int
appDataOverhead Header
header)
#ifdef SSLV2_COMPATIBLE
              sslv2Header :: ByteString -> IO (Either TLSError (Record Plaintext))
sslv2Header ByteString
header =
                if HasCallStack => ByteString -> Word8
B.head ByteString
header forall a. Ord a => a -> a -> Bool
>= Word8
0x80
                    then forall a c b. (a -> c) -> (b -> c) -> Either a b -> c
either (forall (m :: * -> *) a. Monad m => a -> m a
return forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall a b. a -> Either a b
Left) Word16 -> IO (Either TLSError (Record Plaintext))
recvDeprecatedLength forall a b. (a -> b) -> a -> b
$ ByteString -> Either TLSError Word16
decodeDeprecatedHeaderLength ByteString
header
                    else Context -> Int -> IO (Either TLSError ByteString)
readExactBytes Context
ctx Int
3 forall (m :: * -> *) a b. Monad m => m a -> (a -> m b) -> m b
>>=
                            forall a c b. (a -> c) -> (b -> c) -> Either a b -> c
either (forall (m :: * -> *) a. Monad m => a -> m a
return forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall a b. a -> Either a b
Left) (Either TLSError Header -> IO (Either TLSError (Record Plaintext))
recvLengthE forall b c a. (b -> c) -> (a -> b) -> a -> c
. ByteString -> Either TLSError Header
decodeHeader forall b c a. (b -> c) -> (a -> b) -> a -> c
. ByteString -> ByteString -> ByteString
B.append ByteString
header)

              recvDeprecatedLength :: Word16 -> IO (Either TLSError (Record Plaintext))
recvDeprecatedLength Word16
readlen
                | Word16
readlen forall a. Ord a => a -> a -> Bool
> Word16
1024 forall a. Num a => a -> a -> a
* Word16
4     = forall (m :: * -> *) a. Monad m => a -> m a
return forall a b. (a -> b) -> a -> b
$ forall a b. a -> Either a b
Left TLSError
maximumSizeExceeded
                | Bool
otherwise              = do
                    Either TLSError ByteString
res <- Context -> Int -> IO (Either TLSError ByteString)
readExactBytes Context
ctx (forall a b. (Integral a, Num b) => a -> b
fromIntegral Word16
readlen)
                    case Either TLSError ByteString
res of
                      Left TLSError
e -> forall (m :: * -> *) a. Monad m => a -> m a
return forall a b. (a -> b) -> a -> b
$ forall a b. a -> Either a b
Left TLSError
e
                      Right ByteString
content ->
                        let hdr :: Either TLSError Header
hdr = Word16 -> ByteString -> Either TLSError Header
decodeDeprecatedHeader Word16
readlen (Int -> ByteString -> ByteString
B.take Int
3 ByteString
content)
                         in forall a c b. (a -> c) -> (b -> c) -> Either a b -> c
either (forall (m :: * -> *) a. Monad m => a -> m a
return forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall a b. a -> Either a b
Left) (\Header
h -> Context
-> Int
-> Header
-> ByteString
-> IO (Either TLSError (Record Plaintext))
getRecord Context
ctx Int
appDataOverhead Header
h ByteString
content) Either TLSError Header
hdr
#endif

recvRecord13 :: Context -> IO (Either TLSError (Record Plaintext))
recvRecord13 :: Context -> IO (Either TLSError (Record Plaintext))
recvRecord13 Context
ctx = Context -> Int -> IO (Either TLSError ByteString)
readExactBytes Context
ctx Int
5 forall (m :: * -> *) a b. Monad m => m a -> (a -> m b) -> m b
>>= forall a c b. (a -> c) -> (b -> c) -> Either a b -> c
either (forall (m :: * -> *) a. Monad m => a -> m a
return forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall a b. a -> Either a b
Left) (Either TLSError Header -> IO (Either TLSError (Record Plaintext))
recvLengthE forall b c a. (b -> c) -> (a -> b) -> a -> c
. ByteString -> Either TLSError Header
decodeHeader)
  where recvLengthE :: Either TLSError Header -> IO (Either TLSError (Record Plaintext))
recvLengthE = forall a c b. (a -> c) -> (b -> c) -> Either a b -> c
either (forall (m :: * -> *) a. Monad m => a -> m a
return forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall a b. a -> Either a b
Left) Header -> IO (Either TLSError (Record Plaintext))
recvLength
        recvLength :: Header -> IO (Either TLSError (Record Plaintext))
recvLength header :: Header
header@(Header ProtocolType
_ Version
_ Word16
readlen)
          | forall ty. Integral ty => Context -> Int -> ty -> Bool
exceeds Context
ctx Int
256 Word16
readlen = forall (m :: * -> *) a. Monad m => a -> m a
return forall a b. (a -> b) -> a -> b
$ forall a b. a -> Either a b
Left TLSError
maximumSizeExceeded
          | Bool
otherwise               =
              Context -> Int -> IO (Either TLSError ByteString)
readExactBytes Context
ctx (forall a b. (Integral a, Num b) => a -> b
fromIntegral Word16
readlen) forall (m :: * -> *) a b. Monad m => m a -> (a -> m b) -> m b
>>=
                 forall a c b. (a -> c) -> (b -> c) -> Either a b -> c
either (forall (m :: * -> *) a. Monad m => a -> m a
return forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall a b. a -> Either a b
Left) (Context
-> Int
-> Header
-> ByteString
-> IO (Either TLSError (Record Plaintext))
getRecord Context
ctx Int
0 Header
header)

maximumSizeExceeded :: TLSError
maximumSizeExceeded :: TLSError
maximumSizeExceeded = String -> AlertDescription -> TLSError
Error_Protocol String
"record exceeding maximum size" AlertDescription
RecordOverflow

----------------------------------------------------------------

readExactBytes :: Context -> Int -> IO (Either TLSError ByteString)
readExactBytes :: Context -> Int -> IO (Either TLSError ByteString)
readExactBytes Context
ctx Int
sz = do
    ByteString
hdrbs <- Context -> Int -> IO ByteString
contextRecv Context
ctx Int
sz
    if ByteString -> Int
B.length ByteString
hdrbs forall a. Eq a => a -> a -> Bool
== Int
sz
        then forall (m :: * -> *) a. Monad m => a -> m a
return forall a b. (a -> b) -> a -> b
$ forall a b. b -> Either a b
Right ByteString
hdrbs
        else do
            Context -> IO ()
setEOF Context
ctx
            forall (m :: * -> *) a. Monad m => a -> m a
return forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall a b. a -> Either a b
Left forall a b. (a -> b) -> a -> b
$
                if ByteString -> Bool
B.null ByteString
hdrbs
                    then TLSError
Error_EOF
                    else String -> TLSError
Error_Packet (String
"partial packet: expecting " forall a. [a] -> [a] -> [a]
++ forall a. Show a => a -> String
show Int
sz forall a. [a] -> [a] -> [a]
++ String
" bytes, got: " forall a. [a] -> [a] -> [a]
++ forall a. Show a => a -> String
show (ByteString -> Int
B.length ByteString
hdrbs))