module Network.DNS.Message
( Message(..)
+ , MessageID
, MessageType(..)
, Header(..)
, Opcode(..)
, ResponseCode(..)
, Question(..)
, ResourceRecord(..)
+ , DomainName
+ , DomainLabel
+ , TTL
+ , SomeRR(..)
, RecordType(..)
, RecordClass(..)
+
+ , CNAME(..)
+ , HINFO(..)
)
where
import Control.Monad
import Data.Binary
-import Data.Binary.BitPut
+import Data.Binary.BitPut as BP
import Data.Binary.Get as G
-import Data.Binary.Put
+import Data.Binary.Put as P
import Data.Binary.Strict.BitGet as BG
+import qualified Data.ByteString as BS
+import qualified Data.ByteString.Lazy as LBS
+import Data.Typeable
+import qualified Data.IntMap as IM
+import Data.IntMap (IntMap)
import Data.Word
+replicateM' :: Monad m => Int -> (a -> m (b, a)) -> a -> m ([b], a)
+replicateM' = worker []
+ where
+ worker :: Monad m => [b] -> Int -> (a -> m (b, a)) -> a -> m ([b], a)
+ worker soFar 0 _ a = return (reverse soFar, a)
+ worker soFar n f a = do (b, a') <- f a
+ worker (b : soFar) (n - 1) f a'
+
+
data Message
= Message {
msgHeader :: !Header
, msgQuestions :: ![Question]
- , msgAnswers :: ![ResourceRecord]
- , msgAuthorities :: ![ResourceRecord]
- , msgAdditionals :: ![ResourceRecord]
+ , msgAnswers :: ![SomeRR]
+ , msgAuthorities :: ![SomeRR]
+ , msgAdditionals :: ![SomeRR]
}
data Header
= Header {
- hdMessageID :: !Word16
+ hdMessageID :: !MessageID
, hdMessageType :: !MessageType
, hdOpcode :: !Opcode
, hdIsAuthoritativeAnswer :: !Bool
-- + ARCOUNT
}
+type MessageID = Word16
+
data MessageType
= Query
| Response
}
deriving (Show, Eq)
-type DomainName = [[Word8]]
+putQ :: Question -> Put
+putQ q
+ = do putDomainName $ qName q
+ put $ qType q
+ put $ qClass q
+
+getQ :: DecompTable -> Get (Question, DecompTable)
+getQ dt
+ = do (nm, dt') <- getDomainName dt
+ ty <- get
+ cl <- get
+ let q = Question {
+ qName = nm
+ , qType = ty
+ , qClass = cl
+ }
+ return (q, dt')
+
+type DomainName = [DomainLabel]
+type DomainLabel = BS.ByteString
data RecordClass
= IN
| AnyClass -- Only for queries
deriving (Show, Eq)
-data ResourceRecord
- = ResourceRecord {
- rrName :: !DomainName
- , rrType :: !RecordType
- , rrClass :: !RecordClass
- , rrTTL :: !Word32
- , rrData :: ![Word8]
- }
- deriving (Show, Eq)
+class (Typeable rr, Show rr, Eq rr) => ResourceRecord rr where
+ rrName :: rr -> DomainName
+ rrType :: rr -> RecordType
+ rrClass :: rr -> RecordClass
+ rrTTL :: rr -> TTL
+ rrPutData :: rr -> Put
+ rrGetData :: DecompTable -> DomainName -> RecordClass -> TTL -> Get (rr, DecompTable)
+ toRR :: rr -> SomeRR
+ fromRR :: SomeRR -> Maybe rr
+
+ toRR rr = SomeRR rr
+ fromRR (SomeRR rr') = cast rr'
+
+putRR :: ResourceRecord rr => rr -> Put
+putRR rr = do putDomainName $ rrName rr
+ put $ rrType rr
+ put $ rrClass rr
+ putWord32be $ rrTTL rr
+
+ let dat = runPut $ rrPutData rr
+ putWord16be $ fromIntegral $ LBS.length dat
+ putLazyByteString dat
+
+getRR :: DecompTable -> Get (SomeRR, DecompTable)
+getRR dt
+ = do (nm, dt') <- getDomainName dt
+ ty <- get
+ cl <- get
+ ttl <- G.getWord32be
+ case ty of
+ CNAME -> do (rr, dt'') <- rrGetData dt' nm cl ttl
+ return (toRR (rr :: CNAME), dt'')
+ HINFO -> do (rr, dt'') <- rrGetData dt' nm cl ttl
+ return (toRR (rr :: HINFO), dt'')
+ AXFR -> onlyForQuestions "AXFR"
+ MAILB -> onlyForQuestions "MAILB"
+ MAILA -> onlyForQuestions "MAILA"
+ AnyType -> onlyForQuestions "ANY"
+ where
+ onlyForQuestions name
+ = fail (name ++ " is only for questions, not an actual resource record.")
+
+data SomeRR = forall rr. ResourceRecord rr => SomeRR rr
+ deriving Typeable
+instance ResourceRecord SomeRR where
+ rrName (SomeRR rr) = rrName rr
+ rrType (SomeRR rr) = rrType rr
+ rrClass (SomeRR rr) = rrClass rr
+ rrTTL (SomeRR rr) = rrTTL rr
+ rrPutData (SomeRR rr) = rrPutData rr
+ rrGetData _ _ _ _ = fail "SomeRR can't directly be constructed."
+ toRR = id
+ fromRR = Just
+instance Eq SomeRR where
+ (SomeRR a) == (SomeRR b) = Just a == cast b
+instance Show SomeRR where
+ show (SomeRR rr) = show rr
+
+type DecompTable = IntMap BS.ByteString
+type TTL = Word32
+
+data CNAME = CNAME' !DomainName !RecordClass !TTL !DomainName
+ deriving (Eq, Show, Typeable)
+instance ResourceRecord CNAME where
+ rrName (CNAME' n _ _ _) = n
+ rrType _ = CNAME
+ rrClass (CNAME' _ c _ _) = c
+ rrTTL (CNAME' _ _ t _) = t
+ rrGetData dt n c t = do (d, dt') <- getDomainName dt
+ return (CNAME' n c t d, dt')
+ rrPutData (CNAME' _ _ _ d) = putDomainName d
+
+data HINFO = HINFO' !DomainName !RecordClass !TTL !BS.ByteString !BS.ByteString
+ deriving (Eq, Show, Typeable)
+instance ResourceRecord HINFO where
+ rrName (HINFO' n _ _ _ _) = n
+ rrType _ = HINFO
+ rrClass (HINFO' _ c _ _ _) = c
+ rrTTL (HINFO' _ _ t _ _) = t
+ rrGetData dt n c t = do cpu <- getCharString
+ os <- getCharString
+ return (HINFO' n c t cpu os, dt)
+ rrPutData (HINFO' _ _ _ c o) = do putCharString c
+ putCharString o
+
+getDomainName :: DecompTable -> Get (DomainName, DecompTable)
+getDomainName = flip worker []
+ where
+ worker :: DecompTable -> [DomainLabel] -> Get ([DomainLabel], DecompTable)
+ worker dt soFar
+ = do (l, dt') <- getDomainLabel dt
+ case BS.null l of
+ True -> return (reverse (l : soFar), dt')
+ False -> worker dt' (l : soFar)
+
+getDomainLabel :: DecompTable -> Get (DomainLabel, DecompTable)
+getDomainLabel dt
+ = do header <- getByteString 1
+ let Right h
+ = runBitGet header $
+ do a <- getBit
+ b <- getBit
+ n <- liftM fromIntegral (getAsWord8 6)
+ case (a, b) of
+ ( True, True) -> return $ Offset n
+ (False, False) -> return $ Length n
+ _ -> fail "Illegal label header"
+ case h of
+ Offset n
+ -> do let Just l = IM.lookup n dt
+ return (l, dt)
+ Length n
+ -> do offset <- liftM fromIntegral bytesRead
+ label <- getByteString n
+ let dt' = IM.insert offset label dt
+ return (label, dt')
+
+getCharString :: Get BS.ByteString
+getCharString = do len <- G.getWord8
+ getByteString (fromIntegral len)
+
+putCharString :: BS.ByteString -> Put
+putCharString = putDomainLabel
+
+data LabelHeader
+ = Offset !Int
+ | Length !Int
+
+putDomainName :: DomainName -> Put
+putDomainName = mapM_ putDomainLabel
+
+putDomainLabel :: DomainLabel -> Put
+putDomainLabel l
+ = do putWord8 $ fromIntegral $ BS.length l
+ P.putByteString l
data RecordType
= A
| AnyType
deriving (Show, Eq)
+instance Binary Message where
+ put m = do put $ msgHeader m
+ putWord16be $ fromIntegral $ length $ msgQuestions m
+ putWord16be $ fromIntegral $ length $ msgAnswers m
+ putWord16be $ fromIntegral $ length $ msgAuthorities m
+ putWord16be $ fromIntegral $ length $ msgAdditionals m
+ mapM_ putQ $ msgQuestions m
+ mapM_ putRR $ msgAnswers m
+ mapM_ putRR $ msgAuthorities m
+ mapM_ putRR $ msgAdditionals m
+
+ get = do hdr <- get
+ nQ <- liftM fromIntegral G.getWord16be
+ nAns <- liftM fromIntegral G.getWord16be
+ nAth <- liftM fromIntegral G.getWord16be
+ nAdd <- liftM fromIntegral G.getWord16be
+ (qs , dt1) <- replicateM' nQ getQ IM.empty
+ (anss, dt2) <- replicateM' nAns getRR dt1
+ (aths, dt3) <- replicateM' nAth getRR dt2
+ (adds, _ ) <- replicateM' nAdd getRR dt3
+ return Message {
+ msgHeader = hdr
+ , msgQuestions = qs
+ , msgAnswers = anss
+ , msgAuthorities = aths
+ , msgAdditionals = adds
+ }
+
instance Binary Header where
put h = do putWord16be $ hdMessageID h
putLazyByteString flags
toEnum 4 = HS
toEnum 255 = AnyClass
toEnum _ = undefined
+
+instance Binary RecordType where
+ get = liftM (toEnum . fromIntegral) G.getWord16be
+ put = putWord16be . fromIntegral . fromEnum
+
+instance Binary RecordClass where
+ get = liftM (toEnum . fromIntegral) G.getWord16be
+ put = putWord16be . fromIntegral . fromEnum
\ No newline at end of file
projects / haskell-dns.git / commitdiff