module Network.DNS.Message
( Message(..)
+ , MessageID
, MessageType(..)
, Header(..)
, Opcode(..)
, ResponseCode(..)
, Question(..)
, ResourceRecord(..)
- , RecordType(..)
+ , DomainName
+ , DomainLabel
+ , TTL
+ , RecordType
, RecordClass(..)
+
+ , SomeQT
+ , SomeRR
+ , SomeRT
+
+ , A(..)
+ , NS(..)
+ , CNAME(..)
+ , HINFO(..)
+
+ , mkDomainName
+ , wrapQueryType
+ , wrapRecordType
+ , wrapRecord
)
where
+import Control.Exception
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.Char8 as C8 hiding (ByteString)
+import Data.Typeable
+import qualified Data.IntMap as IM
+import Data.IntMap (IntMap)
+import qualified Data.Map as M
+import Data.Map (Map)
import Data.Word
+import Network.DNS.Packer as P
+import Network.DNS.Unpacker as U
+import Network.Socket
data Message
= Message {
msgHeader :: !Header
, msgQuestions :: ![Question]
- , msgAnswers :: ![ResourceRecord]
- , msgAuthorities :: ![ResourceRecord]
- , msgAdditionals :: ![ResourceRecord]
+ , msgAnswers :: ![SomeRR]
+ , msgAuthorities :: ![SomeRR]
+ , msgAdditionals :: ![SomeRR]
}
+ deriving (Show, Eq)
data Header
= Header {
- hdMessageID :: !Word16
+ hdMessageID :: !MessageID
, hdMessageType :: !MessageType
, hdOpcode :: !Opcode
, hdIsAuthoritativeAnswer :: !Bool
-- + NSCOUNT
-- + ARCOUNT
}
+ deriving (Show, Eq)
+
+type MessageID = Word16
data MessageType
= Query
data Question
= Question {
qName :: !DomainName
- , qType :: !RecordType
+ , qType :: !SomeQT
, qClass :: !RecordClass
}
deriving (Show, Eq)
-type DomainName = [[Word8]]
+type SomeQT = SomeRT
+
+putQ :: Question -> Packer CompTable ()
+putQ q
+ = do putDomainName $ qName q
+ putSomeRT $ qType q
+ putBinary $ qClass q
+
+getQ :: Unpacker DecompTable Question
+getQ = do nm <- getDomainName
+ ty <- getSomeRT
+ cl <- getBinary
+ return Question {
+ qName = nm
+ , qType = ty
+ , qClass = cl
+ }
+
+
+newtype DomainName = DN [DomainLabel] deriving (Eq, Show, Ord, Typeable)
+type DomainLabel = BS.ByteString
+
+rootName :: DomainName
+rootName = DN [BS.empty]
+
+isRootName :: DomainName -> Bool
+isRootName (DN [_]) = True
+isRootName _ = False
+
+consLabel :: DomainLabel -> DomainName -> DomainName
+consLabel x (DN ys) = DN (x:ys)
+
+unconsLabel :: DomainName -> (DomainLabel, DomainName)
+unconsLabel (DN (x:xs)) = (x, DN xs)
+unconsLabel x = error ("Illegal use of unconsLabel: " ++ show x)
+
+mkDomainName :: String -> DomainName
+mkDomainName = DN . mkLabels [] . notEmpty
+ where
+ notEmpty :: String -> String
+ notEmpty xs = assert (not $ null xs) xs
+
+ mkLabels :: [DomainLabel] -> String -> [DomainLabel]
+ mkLabels soFar [] = reverse (C8.empty : soFar)
+ mkLabels soFar xs = case break (== '.') xs of
+ (l, ('.':rest))
+ -> mkLabels (C8.pack l : soFar) rest
+ _ -> error ("Illegal domain name: " ++ xs)
data RecordClass
= IN
| AnyClass -- Only for queries
deriving (Show, Eq)
-data ResourceRecord
+
+data RecordType rt dt => ResourceRecord rt dt
= ResourceRecord {
rrName :: !DomainName
- , rrType :: !RecordType
+ , rrType :: !rt
, rrClass :: !RecordClass
- , rrTTL :: !Word32
- , rrData :: ![Word8]
+ , rrTTL :: !TTL
+ , rrData :: !dt
}
- deriving (Show, Eq)
+ deriving (Show, Eq, Typeable)
+
+
+data SomeRR = forall rt dt. RecordType rt dt => SomeRR (ResourceRecord rt dt)
+
+instance Show SomeRR where
+ show (SomeRR rr) = show rr
+
+instance Eq SomeRR where
+ (SomeRR a) == (SomeRR b) = Just a == cast b
+
+
+putSomeRR :: SomeRR -> Packer CompTable ()
+putSomeRR (SomeRR rr) = putResourceRecord rr
+
+getSomeRR :: Unpacker DecompTable SomeRR
+getSomeRR = do srt <- U.lookAhead $
+ do getDomainName -- skip
+ getSomeRT
+ case srt of
+ SomeRT rt
+ -> getResourceRecord rt >>= return . SomeRR
+
+type CompTable = Map DomainName Int
+type DecompTable = IntMap DomainName
+type TTL = Word32
+
+getDomainName :: Unpacker DecompTable DomainName
+getDomainName = worker
+ where
+ worker :: Unpacker DecompTable DomainName
+ worker
+ = do offset <- U.bytesRead
+ hdr <- getLabelHeader
+ case hdr of
+ Offset n
+ -> do dt <- U.getState
+ case IM.lookup n dt of
+ Just name
+ -> return name
+ Nothing
+ -> fail ("Illegal offset of label pointer: " ++ show (n, dt))
+ Length 0
+ -> return rootName
+ Length n
+ -> do label <- U.getByteString n
+ rest <- worker
+ let name = consLabel label rest
+ U.modifyState $ IM.insert offset name
+ return name
+
+ getLabelHeader :: Unpacker s LabelHeader
+ getLabelHeader
+ = do header <- U.lookAhead $ U.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 _
+ -> do header' <- U.getByteString 2 -- Pointers have 2 octets.
+ let Right h'
+ = runBitGet header' $
+ do BG.skip 2
+ n <- liftM fromIntegral (getAsWord16 14)
+ return $ Offset n
+ return h'
+ len@(Length _)
+ -> do U.skip 1
+ return len
+
+
+getCharString :: Unpacker s BS.ByteString
+getCharString = do len <- U.getWord8
+ U.getByteString (fromIntegral len)
+
+putCharString :: BS.ByteString -> Packer s ()
+putCharString xs = do P.putWord8 $ fromIntegral $ BS.length xs
+ P.putByteString xs
+data LabelHeader
+ = Offset !Int
+ | Length !Int
+
+putDomainName :: DomainName -> Packer CompTable ()
+putDomainName name
+ = do ct <- P.getState
+ case M.lookup name ct of
+ Just n
+ -> do let ptr = runBitPut $
+ do putBit True
+ putBit True
+ putNBits 14 n
+ P.putLazyByteString ptr
+ Nothing
+ -> do offset <- bytesWrote
+ P.modifyState $ M.insert name offset
+
+ let (label, rest) = unconsLabel name
+
+ putCharString label
+
+ if isRootName rest then
+ P.putWord8 0
+ else
+ putDomainName rest
+
+
+class (Show rt, Show dt, Eq rt, Eq dt, Typeable rt, Typeable dt) => RecordType rt dt | rt -> dt where
+ rtToInt :: rt -> Int
+ putRecordData :: rt -> dt -> Packer CompTable ()
+ getRecordData :: rt -> Unpacker DecompTable dt
+
+ putRecordType :: rt -> Packer s ()
+ putRecordType = P.putWord16be . fromIntegral . rtToInt
+
+ putResourceRecord :: ResourceRecord rt dt -> Packer CompTable ()
+ putResourceRecord rr
+ = do putDomainName $ rrName rr
+ putRecordType $ rrType rr
+ putBinary $ rrClass rr
+ P.putWord32be $ rrTTL rr
+
+ -- First, write a dummy data length.
+ offset <- bytesWrote
+ P.putWord16be 0
+
+ -- Second, write data.
+ putRecordData (rrType rr) (rrData rr)
+
+ -- Third, rewrite the dummy length to an actual value.
+ offset' <- bytesWrote
+ withOffset offset
+ $ P.putWord16be (fromIntegral (offset' - offset - 2))
+
+ getResourceRecord :: rt -> Unpacker DecompTable (ResourceRecord rt dt)
+ getResourceRecord rt
+ = do name <- getDomainName
+ U.skip 2 -- record type
+ cl <- getBinary
+ ttl <- U.getWord32be
+ U.skip 2 -- data length
+ dat <- getRecordData rt
+ return $ ResourceRecord {
+ rrName = name
+ , rrType = rt
+ , rrClass = cl
+ , rrTTL = ttl
+ , rrData = dat
+ }
+
+data SomeRT = forall rt dt. RecordType rt dt => SomeRT rt
+
+instance Show SomeRT where
+ show (SomeRT rt) = show rt
+
+instance Eq SomeRT where
+ (SomeRT a) == (SomeRT b) = Just a == cast b
+
+putSomeRT :: SomeRT -> Packer s ()
+putSomeRT (SomeRT rt) = putRecordType rt
+
+getSomeRT :: Unpacker s SomeRT
+getSomeRT = do n <- liftM fromIntegral U.getWord16be
+ case IM.lookup n defaultRTTable of
+ Nothing
+ -> fail ("Unknown resource record type: " ++ show n)
+ Just srt
+ -> return srt
+
+data A = A deriving (Show, Eq, Typeable)
+instance RecordType A HostAddress where
+ rtToInt _ = 1
+ putRecordData _ = P.putWord32be
+ getRecordData _ = U.getWord32be
+
+data NS = NS deriving (Show, Eq, Typeable)
+instance RecordType NS DomainName where
+ rtToInt _ = 2
+ putRecordData _ = putDomainName
+ getRecordData _ = getDomainName
+
+data CNAME = CNAME deriving (Show, Eq, Typeable)
+instance RecordType CNAME DomainName where
+ rtToInt _ = 5
+ putRecordData _ = putDomainName
+ getRecordData _ = getDomainName
+
+data HINFO = HINFO deriving (Show, Eq, Typeable)
+instance RecordType HINFO (BS.ByteString, BS.ByteString) where
+ rtToInt _ = 13
+ putRecordData _ (cpu, os) = do putCharString cpu
+ putCharString os
+ getRecordData _ = do cpu <- getCharString
+ os <- getCharString
+ return (cpu, os)
+
+
+{-
data RecordType
= A
| NS
| MAILA -- Obsolete
| AnyType
deriving (Show, Eq)
+-}
+
+instance Binary Message where
+ put m = P.liftToBinary M.empty $
+ do putBinary $ msgHeader m
+ P.putWord16be $ fromIntegral $ length $ msgQuestions m
+ P.putWord16be $ fromIntegral $ length $ msgAnswers m
+ P.putWord16be $ fromIntegral $ length $ msgAuthorities m
+ P.putWord16be $ fromIntegral $ length $ msgAdditionals m
+ mapM_ putQ $ msgQuestions m
+ mapM_ putSomeRR $ msgAnswers m
+ mapM_ putSomeRR $ msgAuthorities m
+ mapM_ putSomeRR $ msgAdditionals m
+
+ get = U.liftToBinary IM.empty $
+ do hdr <- getBinary
+ nQ <- liftM fromIntegral U.getWord16be
+ nAns <- liftM fromIntegral U.getWord16be
+ nAth <- liftM fromIntegral U.getWord16be
+ nAdd <- liftM fromIntegral U.getWord16be
+ qs <- replicateM nQ getQ
+ anss <- replicateM nAns getSomeRR
+ aths <- replicateM nAth getSomeRR
+ adds <- replicateM nAdd getSomeRR
+ return Message {
+ msgHeader = hdr
+ , msgQuestions = qs
+ , msgAnswers = anss
+ , msgAuthorities = aths
+ , msgAdditionals = adds
+ }
instance Binary Header where
- put h = do putWord16be $ hdMessageID h
- putLazyByteString flags
+ put h = do P'.putWord16be $ hdMessageID h
+ P'.putLazyByteString flags
where
flags = runBitPut $
do putNBits 1 $ fromEnum $ hdMessageType h
putNBits 4 $ fromEnum $ hdResponseCode h
get = do mID <- G.getWord16be
- flags <- getByteString 2
+ flags <- G.getByteString 2
let Right hd
= runBitGet flags $
do qr <- liftM (toEnum . fromIntegral) $ getAsWord8 1
toEnum 5 = Refused
toEnum _ = undefined
+{-
instance Enum RecordType where
fromEnum A = 1
fromEnum NS = 2
toEnum 254 = MAILA
toEnum 255 = AnyType
toEnum _ = undefined
+-}
instance Enum RecordClass where
fromEnum IN = 1
toEnum 4 = HS
toEnum 255 = AnyClass
toEnum _ = undefined
+
+instance Binary RecordClass where
+ get = liftM (toEnum . fromIntegral) G.getWord16be
+ put = P'.putWord16be . fromIntegral . fromEnum
+
+
+defaultRTTable :: IntMap SomeRT
+defaultRTTable = IM.fromList $ map toPair $
+ [ wrapRecordType A
+ , wrapRecordType NS
+ , wrapRecordType CNAME
+ , wrapRecordType HINFO
+ ]
+ where
+ toPair :: SomeRT -> (Int, SomeRT)
+ toPair srt@(SomeRT rt) = (rtToInt rt, srt)
+
+
+wrapQueryType :: RecordType rt dt => rt -> SomeQT
+wrapQueryType = SomeRT
+
+wrapRecordType :: RecordType rt dt => rt -> SomeRT
+wrapRecordType = SomeRT
+
+wrapRecord :: RecordType rt dt => ResourceRecord rt dt -> SomeRR
+wrapRecord = SomeRR
\ No newline at end of file
projects / haskell-dns.git / blobdiff