module Network.DNS.Message
- ( Header(..)
+ ( Message(..)
+ , MessageID
+ , MessageType(..)
+ , Header(..)
, Opcode(..)
, ResponseCode(..)
+ , Question(..)
+ , ResourceRecord(..)
+ , 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.Get
-import Data.Binary.Put
-import Data.Bits
+import Data.Binary.BitPut as BP
+import Data.Binary.Get as G
+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 qualified Data.ByteString.Lazy as LBS
+import Data.Typeable
+import qualified Data.IntMap as IM
+import Data.IntMap (IntMap)
import Data.Word
+import Network.Socket
-data Header
- = QueryHeader {
- hdMessageID :: !Word16
- , hdOpcode :: !Opcode
- , hdIsTruncated :: !Bool
- , hdIsRecursionDesired :: !Bool
+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 :: ![SomeRR]
+ , msgAuthorities :: ![SomeRR]
+ , msgAdditionals :: ![SomeRR]
}
- | ResponseHeader {
- hdMessageID :: !Word16
+ deriving (Show, Eq)
+
+data Header
+ = Header {
+ hdMessageID :: !MessageID
+ , hdMessageType :: !MessageType
, hdOpcode :: !Opcode
, hdIsAuthoritativeAnswer :: !Bool
, hdIsTruncated :: !Bool
, hdIsRecursionDesired :: !Bool
, hdIsRecursionAvailable :: !Bool
, hdResponseCode :: !ResponseCode
+
+ -- These fields are supressed in this data structure:
+ -- + QDCOUNT
+ -- + ANCOUNT
+ -- + NSCOUNT
+ -- + ARCOUNT
}
+ deriving (Show, Eq)
+
+type MessageID = Word16
+
+data MessageType
+ = Query
+ | Response
+ deriving (Show, Eq)
data Opcode
= StandardQuery
| InverseQuery
| ServerStatusRequest
+ deriving (Show, Eq)
data ResponseCode
= NoError
| Refused
deriving (Show, Eq)
-hdIsResponse :: Header -> Bool
-hdIsResponse (QueryHeader _ _ _ _ ) = False
-hdIsResponse (ResponseHeader _ _ _ _ _ _ _) = True
+data Question
+ = Question {
+ qName :: !DomainName
+ , qType :: !SomeQT
+ , qClass :: !RecordClass
+ }
+ deriving (Show, Eq)
+
+type SomeQT = SomeRT
+
+putQ :: Question -> Put
+putQ q
+ = do putDomainName $ qName q
+ putSomeRT $ qType q
+ put $ qClass q
+
+getQ :: DecompTable -> Get (Question, DecompTable)
+getQ dt
+ = do (nm, dt') <- getDomainName dt
+ ty <- getSomeRT
+ cl <- get
+ let q = Question {
+ qName = nm
+ , qType = ty
+ , qClass = cl
+ }
+ return (q, dt')
+
+newtype DomainName = DN [DomainLabel] deriving (Eq, Show, Typeable)
+type DomainLabel = BS.ByteString
+
+nameToLabels :: DomainName -> [DomainLabel]
+nameToLabels (DN ls) = ls
+
+labelsToName :: [DomainLabel] -> DomainName
+labelsToName = DN
+
+rootName :: DomainName
+rootName = DN [BS.empty]
+
+consLabel :: DomainLabel -> DomainName -> DomainName
+consLabel x (DN ys) = DN (x:ys)
+
+mkDomainName :: String -> DomainName
+mkDomainName = labelsToName . 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
+ | CS -- Obsolete
+ | CH
+ | HS
+ | AnyClass -- Only for queries
+ deriving (Show, Eq)
+
+
+data RecordType rt dt => ResourceRecord rt dt
+ = ResourceRecord {
+ rrName :: !DomainName
+ , rrType :: !rt
+ , rrClass :: !RecordClass
+ , rrTTL :: !TTL
+ , rrData :: !dt
+ }
+ deriving (Show, Eq, Typeable)
+
+
+putRR :: forall rt dt. RecordType rt dt => ResourceRecord rt dt -> Put
+putRR rr = do putDomainName $ rrName rr
+ putRecordType $ rrType rr
+ put $ rrClass rr
+ putWord32be $ rrTTL rr
+
+ let dat = runPut $
+ putRecordData (undefined :: rt) (rrData rr)
+ putWord16be $ fromIntegral $ LBS.length dat
+ putLazyByteString dat
+
+
+getRR :: forall rt dt. RecordType rt dt => DecompTable -> rt -> Get (ResourceRecord rt dt, DecompTable)
+getRR dt rt
+ = do (nm, dt1) <- getDomainName dt
+ G.skip 2 -- record type
+ cl <- get
+ ttl <- G.getWord32be
+ G.skip 2 -- data length
+ (dat, dt2) <- getRecordData (undefined :: rt) dt1
+
+ let rr = ResourceRecord {
+ rrName = nm
+ , rrType = rt
+ , rrClass = cl
+ , rrTTL = ttl
+ , rrData = dat
+ }
+ return (rr, dt2)
+
+
+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 -> Put
+putSomeRR (SomeRR rr) = putRR rr
+
+getSomeRR :: DecompTable -> Get (SomeRR, DecompTable)
+getSomeRR dt
+ = do srt <- lookAhead $
+ do getDomainName dt -- skip
+ getSomeRT
+ case srt of
+ SomeRT rt -> getRR dt rt >>= \ (rr, dt') -> return (SomeRR rr, dt')
+
+
+type DecompTable = IntMap DomainName
+type TTL = Word32
+
+getDomainName :: DecompTable -> Get (DomainName, DecompTable)
+getDomainName = worker
+ where
+ worker :: DecompTable -> Get (DomainName, DecompTable)
+ worker dt
+ = do offset <- liftM fromIntegral bytesRead
+ hdr <- getLabelHeader
+ case hdr of
+ Offset n
+ -> case IM.lookup n dt of
+ Just name
+ -> return (name, dt)
+ Nothing
+ -> fail ("Illegal offset of label pointer: " ++ show (n, dt))
+ Length 0
+ -> return (rootName, dt)
+ Length n
+ -> do label <- getByteString n
+ (rest, dt') <- worker dt
+ let name = consLabel label rest
+ dt'' = IM.insert offset name dt'
+ return (name, dt'')
+
+ getLabelHeader :: Get LabelHeader
+ getLabelHeader
+ = do header <- lookAhead $ 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' <- 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 G.skip 1
+ return len
+
+
+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 . nameToLabels
+
+putDomainLabel :: DomainLabel -> Put
+putDomainLabel l
+ = do putWord8 $ fromIntegral $ BS.length l
+ P.putByteString l
+
+class (Show rt, Show dt, Eq rt, Eq dt, Typeable rt, Typeable dt) => RecordType rt dt | rt -> dt where
+ rtToInt :: rt -> Int
+ putRecordType :: rt -> Put
+ putRecordData :: rt -> dt -> Put
+ getRecordData :: rt -> DecompTable -> Get (dt, DecompTable)
+
+ putRecordType = putWord16be . fromIntegral . rtToInt
+
+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 -> Put
+putSomeRT (SomeRT rt) = putRecordType rt
+
+getSomeRT :: Get SomeRT
+getSomeRT = do n <- liftM fromIntegral G.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 _ = putWord32be
+ getRecordData _ = \ dt ->
+ do addr <- G.getWord32be
+ return (addr, dt)
+
+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 _ dt = do cpu <- getCharString
+ os <- getCharString
+ return ((cpu, os), dt)
+
+
+{-
+data RecordType
+ = A
+ | NS
+ | MD
+ | MF
+ | CNAME
+ | SOA
+ | MB
+ | MG
+ | MR
+ | NULL
+ | WKS
+ | PTR
+ | HINFO
+ | MINFO
+ | MX
+ | TXT
+
+ -- Only for queries:
+ | AXFR
+ | MAILB -- Obsolete
+ | MAILA -- Obsolete
+ | 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_ putSomeRR $ msgAnswers m
+ mapM_ putSomeRR $ msgAuthorities m
+ mapM_ putSomeRR $ 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 getSomeRR dt1
+ (aths, dt3) <- replicateM' nAth getSomeRR dt2
+ (adds, _ ) <- replicateM' nAdd getSomeRR dt3
+ return Message {
+ msgHeader = hdr
+ , msgQuestions = qs
+ , msgAnswers = anss
+ , msgAuthorities = aths
+ , msgAdditionals = adds
+ }
instance Binary Header where
put h = do putWord16be $ hdMessageID h
- let qr = boolToNum $ hdIsResponse h
- op = fromIntegral $ fromEnum $ hdOpcode h
- aa = if hdIsResponse h then
- boolToNum $ hdIsAuthoritativeAnswer h
- else
- 0
- tc = boolToNum $ hdIsTruncated h
- rd = boolToNum $ hdIsRecursionDesired h
- ra = if hdIsResponse h then
- boolToNum $ hdIsRecursionAvailable h
- else
- 0
- rc = if hdIsResponse h then
- fromIntegral $ fromEnum $ hdResponseCode h
- else
- 0
- flags = ((qr `shiftL` 15) .&. 0x01) .|.
- ((op `shiftL` 11) .&. 0x0F) .|.
- ((aa `shiftL` 10) .&. 0x01) .|.
- ((tc `shiftL` 9) .&. 0x01) .|.
- ((rd `shiftL` 8) .&. 0x01) .|.
- ((ra `shiftL` 7) .&. 0x01) .|.
- ((rc `shiftL` 0) .&. 0x0F)
- putWord16be flags
+ putLazyByteString flags
where
- boolToNum :: Num a => Bool -> a
- boolToNum True = 1
- boolToNum False = 0
-
- get = do mID <- getWord16be
- flags <- getWord16be
- let qr = testBit flags 15
- op = toEnum $ fromIntegral ((flags `shiftR` 11) .&. 0x0F)
- aa = testBit flags 10
- tc = testBit flags 9
- rd = testBit flags 8
- ra = testBit flags 7
- rc = toEnum $ fromIntegral (flags .&. 0x0F)
- hd = if qr then
- ResponseHeader {
- hdMessageID = mID
- , hdOpcode = op
- , hdIsAuthoritativeAnswer = aa
- , hdIsTruncated = tc
- , hdIsRecursionDesired = rd
- , hdIsRecursionAvailable = ra
- , hdResponseCode = rc
- }
- else
- QueryHeader {
- hdMessageID = mID
- , hdOpcode = op
- , hdIsTruncated = tc
- , hdIsRecursionDesired = rd
- }
+ flags = runBitPut $
+ do putNBits 1 $ fromEnum $ hdMessageType h
+ putNBits 4 $ fromEnum $ hdOpcode h
+ putBit $ hdIsAuthoritativeAnswer h
+ putBit $ hdIsTruncated h
+ putBit $ hdIsRecursionDesired h
+ putBit $ hdIsRecursionAvailable h
+ putNBits 3 (0 :: Int)
+ putNBits 4 $ fromEnum $ hdResponseCode h
+
+ get = do mID <- G.getWord16be
+ flags <- getByteString 2
+ let Right hd
+ = runBitGet flags $
+ do qr <- liftM (toEnum . fromIntegral) $ getAsWord8 1
+ op <- liftM (toEnum . fromIntegral) $ getAsWord8 4
+ aa <- getBit
+ tc <- getBit
+ rd <- getBit
+ ra <- getBit
+ BG.skip 3
+ rc <- liftM (toEnum . fromIntegral) $ getAsWord8 4
+ return Header {
+ hdMessageID = mID
+ , hdMessageType = qr
+ , hdOpcode = op
+ , hdIsAuthoritativeAnswer = aa
+ , hdIsTruncated = tc
+ , hdIsRecursionDesired = rd
+ , hdIsRecursionAvailable = ra
+ , hdResponseCode = rc
+ }
return hd
+instance Enum MessageType where
+ fromEnum Query = 0
+ fromEnum Response = 1
+
+ toEnum 0 = Query
+ toEnum 1 = Response
+ toEnum _ = undefined
+
instance Enum Opcode where
fromEnum StandardQuery = 0
fromEnum InverseQuery = 1
toEnum 2 = ServerStatusRequest
toEnum _ = undefined
-instance Bounded Opcode where
- minBound = StandardQuery
- maxBound = ServerStatusRequest
-
instance Enum ResponseCode where
fromEnum NoError = 0
fromEnum FormatError = 1
toEnum 5 = Refused
toEnum _ = undefined
-instance Bounded ResponseCode where
- minBound = NoError
- maxBound = Refused
+{-
+instance Enum RecordType where
+ fromEnum A = 1
+ fromEnum NS = 2
+ fromEnum MD = 3
+ fromEnum MF = 4
+ fromEnum CNAME = 5
+ fromEnum SOA = 6
+ fromEnum MB = 7
+ fromEnum MG = 8
+ fromEnum MR = 9
+ fromEnum NULL = 10
+ fromEnum WKS = 11
+ fromEnum PTR = 12
+ fromEnum HINFO = 13
+ fromEnum MINFO = 14
+ fromEnum MX = 15
+ fromEnum TXT = 16
+ fromEnum AXFR = 252
+ fromEnum MAILB = 253
+ fromEnum MAILA = 254
+ fromEnum AnyType = 255
+
+ toEnum 1 = A
+ toEnum 2 = NS
+ toEnum 3 = MD
+ toEnum 4 = MF
+ toEnum 5 = CNAME
+ toEnum 6 = SOA
+ toEnum 7 = MB
+ toEnum 8 = MG
+ toEnum 9 = MR
+ toEnum 10 = NULL
+ toEnum 11 = WKS
+ toEnum 12 = PTR
+ toEnum 13 = HINFO
+ toEnum 14 = MINFO
+ toEnum 15 = MX
+ toEnum 16 = TXT
+ toEnum 252 = AXFR
+ toEnum 253 = MAILB
+ toEnum 254 = MAILA
+ toEnum 255 = AnyType
+ toEnum _ = undefined
+-}
+
+instance Enum RecordClass where
+ fromEnum IN = 1
+ fromEnum CS = 2
+ fromEnum CH = 3
+ fromEnum HS = 4
+ fromEnum AnyClass = 255
+
+ toEnum 1 = IN
+ toEnum 2 = CS
+ toEnum 3 = CH
+ toEnum 4 = HS
+ toEnum 255 = AnyClass
+ toEnum _ = undefined
+
+instance Binary RecordClass where
+ get = liftM (toEnum . fromIntegral) G.getWord16be
+ put = 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