diff options
Diffstat (limited to 'Codec')
-rw-r--r-- | Codec/MIME/Base64.hs | 147 | ||||
-rw-r--r-- | Codec/MIME/Decode.hs | 76 | ||||
-rw-r--r-- | Codec/MIME/Parse.hs | 296 | ||||
-rw-r--r-- | Codec/MIME/QuotedPrintable.hs | 66 | ||||
-rw-r--r-- | Codec/MIME/Type.hs | 187 | ||||
-rw-r--r-- | Codec/MIME/Utils.hs | 33 |
6 files changed, 805 insertions, 0 deletions
diff --git a/Codec/MIME/Base64.hs b/Codec/MIME/Base64.hs new file mode 100644 index 0000000..f60419b --- /dev/null +++ b/Codec/MIME/Base64.hs @@ -0,0 +1,147 @@ +-------------------------------------------------------------------- +-- | +-- Module : Codec.MIME.Base64 +-- Copyright : (c) 2006-2009, Galois, Inc. +-- License : BSD3 +-- +-- Maintainer: Sigbjorn Finne <sigbjorn.finne@gmail.com> +-- Stability : provisional +-- Portability: portable +-- +-- +-- Base64 decoding and encoding routines, multiple entry +-- points for either depending on use and level of control +-- wanted over the encoded output (and its input form on the +-- decoding side.) +-- +-------------------------------------------------------------------- +module Codec.MIME.Base64 + ( encodeRaw -- :: Bool -> String -> [Word8] + , encodeRawString -- :: Bool -> String -> String + , encodeRawPrim -- :: Bool -> Char -> Char -> [Word8] -> String + + , formatOutput -- :: Int -> Maybe String -> String -> String + + , decode -- :: String -> [Word8] + , decodeToString -- :: String -> String + , decodePrim -- :: Char -> Char -> String -> [Word8] + ) where + +import Data.Bits +import Data.Char +import Data.Word +import Data.Maybe + +encodeRawString :: Bool -> String -> String +encodeRawString trail xs = encodeRaw trail (map (fromIntegral.ord) xs) + +-- | @formatOutput n mbLT str@ formats @str@, splitting it +-- into lines of length @n@. The optional value lets you control what +-- line terminator sequence to use; the default is CRLF (as per MIME.) +formatOutput :: Int -> Maybe String -> String -> String +formatOutput n mbTerm str + | n <= 0 = error ("Codec.MIME.Base64.formatOutput: negative line length " ++ show n) + | otherwise = chop n str + where + crlf :: String + crlf = fromMaybe "\r\n" mbTerm + + chop _ "" = "" + chop i xs = + case splitAt i xs of + (as,"") -> as + (as,bs) -> as ++ crlf ++ chop i bs + +encodeRaw :: Bool -> [Word8] -> String +encodeRaw trail bs = encodeRawPrim trail '+' '/' bs + +-- | @encodeRawPrim@ lets you control what non-alphanum characters to use +-- (The base64url variation uses @*@ and @-@, for instance.) +-- No support for mapping these to multiple characters in the output though. +encodeRawPrim :: Bool -> Char -> Char -> [Word8] -> String +encodeRawPrim trail ch62 ch63 ls = encoder ls + where + trailer xs ys + | not trail = xs + | otherwise = xs ++ ys + f = fromB64 ch62 ch63 + encoder [] = [] + encoder [x] = trailer (take 2 (encode3 f x 0 0 "")) "==" + encoder [x,y] = trailer (take 3 (encode3 f x y 0 "")) "=" + encoder (x:y:z:ws) = encode3 f x y z (encoder ws) + +encode3 :: (Word8 -> Char) -> Word8 -> Word8 -> Word8 -> String -> String +encode3 f a b c rs = + f (low6 (w24 `shiftR` 18)) : + f (low6 (w24 `shiftR` 12)) : + f (low6 (w24 `shiftR` 6)) : + f (low6 w24) : rs + where + w24 :: Word32 + w24 = (fromIntegral a `shiftL` 16) + + (fromIntegral b `shiftL` 8) + + fromIntegral c + +decodeToString :: String -> String +decodeToString str = map (chr.fromIntegral) $ decode str + +decode :: String -> [Word8] +decode str = decodePrim '+' '/' str + +decodePrim :: Char -> Char -> String -> [Word8] +decodePrim ch62 ch63 str = decoder $ takeUntilEnd str + where + takeUntilEnd "" = [] + takeUntilEnd ('=':_) = [] + takeUntilEnd (x:xs) = + case toB64 ch62 ch63 x of + Nothing -> takeUntilEnd xs + Just b -> b : takeUntilEnd xs + +decoder :: [Word8] -> [Word8] +decoder [] = [] +decoder [x] = take 1 (decode4 x 0 0 0 []) +decoder [x,y] = take 1 (decode4 x y 0 0 []) -- upper 4 bits of second val are known to be 0. +decoder [x,y,z] = take 2 (decode4 x y z 0 []) +decoder (x:y:z:w:xs) = decode4 x y z w (decoder xs) + +decode4 :: Word8 -> Word8 -> Word8 -> Word8 -> [Word8] -> [Word8] +decode4 a b c d rs = + (lowByte (w24 `shiftR` 16)) : + (lowByte (w24 `shiftR` 8)) : + (lowByte w24) : rs + where + w24 :: Word32 + w24 = + (fromIntegral a) `shiftL` 18 .|. + (fromIntegral b) `shiftL` 12 .|. + (fromIntegral c) `shiftL` 6 .|. + (fromIntegral d) + +toB64 :: Char -> Char -> Char -> Maybe Word8 +toB64 a b ch + | ch >= 'A' && ch <= 'Z' = Just (fromIntegral (ord ch - ord 'A')) + | ch >= 'a' && ch <= 'z' = Just (26 + fromIntegral (ord ch - ord 'a')) + | ch >= '0' && ch <= '9' = Just (52 + fromIntegral (ord ch - ord '0')) + | ch == a = Just 62 + | ch == b = Just 63 + | otherwise = Nothing + +fromB64 :: Char -> Char -> Word8 -> Char +fromB64 ch62 ch63 x + | x < 26 = chr (ord 'A' + xi) + | x < 52 = chr (ord 'a' + (xi-26)) + | x < 62 = chr (ord '0' + (xi-52)) + | x == 62 = ch62 + | x == 63 = ch63 + | otherwise = error ("fromB64: index out of range " ++ show x) + where + xi :: Int + xi = fromIntegral x + +low6 :: Word32 -> Word8 +low6 x = fromIntegral (x .&. 0x3f) + +lowByte :: Word32 -> Word8 +lowByte x = (fromIntegral x) .&. 0xff + diff --git a/Codec/MIME/Decode.hs b/Codec/MIME/Decode.hs new file mode 100644 index 0000000..278d6f6 --- /dev/null +++ b/Codec/MIME/Decode.hs @@ -0,0 +1,76 @@ +-------------------------------------------------------------------- +-- | +-- Module : Codec.MIME.Decode +-- Copyright : (c) 2006-2009, Galois, Inc. +-- License : BSD3 +-- +-- Maintainer: Sigbjorn Finne <sigbjorn.finne@gmail.com> +-- Stability : provisional +-- Portability: portable +-- +-- +-- +-------------------------------------------------------------------- + +module Codec.MIME.Decode where + +import Data.Char + +import Codec.MIME.QuotedPrintable as QP +import Codec.MIME.Base64 as Base64 + +-- | @decodeBody enc str@ decodes @str@ according to the scheme +-- specified by @enc@. Currently, @base64@ and @quoted-printable@ are +-- the only two encodings supported. If you supply anything else +-- for @enc@, @decodeBody@ returns @str@. +-- +decodeBody :: String -> String -> String +decodeBody enc body = + case map toLower enc of + "base64" -> Base64.decodeToString body + "quoted-printable" -> QP.decode body + _ -> body + +-- Decoding of RFC 2047's "encoded-words" production +-- (as used in email-headers and some HTTP header cases +-- (AtomPub's Slug: header)) +decodeWord :: String -> Maybe (String, String) +decodeWord str = + case str of + '=':'?':xs -> + case dropLang $ break (\ch -> ch =='?' || ch == '*') xs of + (cs,_:x:'?':bs) + | isKnownCharset (map toLower cs) -> + case toLower x of + 'q' -> decodeQ cs (break (=='?') bs) + 'b' -> decodeB cs (break (=='?') bs) + _ -> Nothing + _ -> Nothing + _ -> Nothing + where + isKnownCharset cs = cs `elem` ["iso-8859-1", "us-ascii"] + + -- ignore RFC 2231 extension of permitting a language tag to be supplied + -- after the charset. + dropLang (as,'*':bs) = (as,dropWhile (/='?') bs) + dropLang (as,bs) = (as,bs) + + decodeQ cset (fs,'?':'=':rs) = Just (fromCharset cset (QP.decode fs),rs) + decodeQ _ _ = Nothing + + decodeB cset (fs,'?':'=':rs) = + Just (fromCharset cset (Base64.decodeToString fs),rs) + decodeB _ _ = Nothing + + fromCharset _cset cs = cs + +decodeWords :: String -> String +decodeWords "" = "" +decodeWords (x:xs) + | isSpace x = x : decodeWords xs + | otherwise = + case decodeWord (x:xs) of + Nothing -> x : decodeWords xs + Just (as,bs) -> as ++ decodeWords bs + + diff --git a/Codec/MIME/Parse.hs b/Codec/MIME/Parse.hs new file mode 100644 index 0000000..f9dfeb2 --- /dev/null +++ b/Codec/MIME/Parse.hs @@ -0,0 +1,296 @@ +{-# LANGUAGE OverloadedStrings #-} +-------------------------------------------------------------------- +-- | +-- Module : Codec.MIME.Pare +-- Copyright : (c) 2006-2009, Galois, Inc. +-- License : BSD3 +-- +-- Maintainer: Sigbjorn Finne <sigbjorn.finne@gmail.com> +-- Stability : provisional +-- Portability: portable +-- +-- Parsing MIME content. +-- +-------------------------------------------------------------------- +module Codec.MIME.Parse + ( parseMIMEBody -- :: [(T.Text,T.Text)] -> T.Text -> MIMEValue + , parseMIMEType -- :: T.Text -> Maybe Type + , parseMIMEMessage -- :: T.Text -> MIMEValue + + , parseHeaders -- :: T.Text -> ([(T.Text,T.Text)], T.Text) + , parseMultipart -- :: Type -> T.Text -> (MIMEValue, T.Text) + , parseContentType -- :: T.Text -> Maybe Type + , splitMulti -- :: T.Text -> T.Text -> ([MIMEValue], T.Text) + , normalizeCRLF + ) where + +import Codec.MIME.Type +import Codec.MIME.Decode +import Control.Arrow(second) + +import Data.Char +import Data.Maybe +import qualified Data.List as L +import Debug.Trace ( trace ) +import qualified Data.Text as T +import Data.Monoid(Monoid(..), (<>)) + +enableTrace :: Bool +enableTrace = False + +doTrace :: String -> b -> b +doTrace | enableTrace = trace + | otherwise = \_ x -> x + + +parseMIMEBody :: [MIMEParam] -> T.Text -> MIMEValue +parseMIMEBody headers_in body = result { mime_val_headers = headers } + where + result = case mimeType mty of + Multipart{} -> fst (parseMultipart mty body) + Message{} -> fst (parseMultipart mty body) + _ -> nullMIMEValue { mime_val_type = mty + , mime_val_disp = parseContentDisp headers + , mime_val_content = Single (processBody headers body) + } + headers = [ MIMEParam (T.toLower k) v | (MIMEParam k v) <- headers_in ] + mty = fromMaybe defaultType + (parseContentType =<< lookupField "content-type" (paramPairs headers)) +defaultType :: Type +defaultType = Type { mimeType = Text "plain" + , mimeParams = [MIMEParam "charset" "us-ascii"] + } + +parseContentDisp :: [MIMEParam] -> Maybe Disposition +parseContentDisp headers = + (processDisp . dropFoldingWSP) =<< lookupField "content-disposition" (paramPairs headers) + where + processDisp t | T.null t = Nothing + | T.null bs = Just $ Disposition { dispType = toDispType (T.toLower as) + , dispParams = [] + } + | otherwise = Just $ Disposition { dispType = toDispType (T.toLower as) + , dispParams = processParams (parseParams bs) + } + where (as,bs) = T.break (\ch -> isSpace ch || ch == ';') t + + processParams = map procP + where + procP (MIMEParam as val) + | "name" == asl = Name val + | "filename" == asl = Filename val + | "creation-date" == asl = CreationDate val + | "modification-date" == asl = ModDate val + | "read-date" == asl = ReadDate val + | "size" == asl = Size val + | otherwise = OtherParam asl val + where asl = T.toLower as + + toDispType t = if t == "inline" then DispInline + else if t == "attachment" then DispAttachment + else if t == "form-data" then DispFormData + else DispOther t + +paramPairs :: [MIMEParam] -> [(T.Text, T.Text)] +paramPairs = map paramPair + where + paramPair (MIMEParam a b) = (a,b) + +processBody :: [MIMEParam] -> T.Text -> T.Text +processBody headers body = + case lookupField "content-transfer-encoding" $ paramPairs headers of + Nothing -> body + Just v -> T.pack $ decodeBody (T.unpack v) $ T.unpack body + +normalizeCRLF :: T.Text -> T.Text +normalizeCRLF t + | T.null t = "" + | "\r\n" `T.isPrefixOf` t = "\r\n" <> normalizeCRLF (T.drop 2 t) + | any (`T.isPrefixOf` t) ["\r", "\n"] = "\r\n" <> normalizeCRLF (T.drop 1 t) + | otherwise = let (a,b) = T.break (`elem` "\r\n") t in a <> normalizeCRLF b + +parseMIMEMessage :: T.Text -> MIMEValue +parseMIMEMessage entity = + case parseHeaders (normalizeCRLF entity) of + (as,bs) -> parseMIMEBody as bs + +parseHeaders :: T.Text -> ([MIMEParam], T.Text) +parseHeaders str = + case findFieldName "" str of + Left (nm, rs) -> parseFieldValue nm (dropFoldingWSP rs) + Right body -> ([],body) + where + findFieldName acc t + | T.null t = Right "" + | "\r\n" `T.isPrefixOf` t = Right $ T.drop 2 t + | ":" `T.isPrefixOf` t = Left (T.reverse $ T.dropWhile isHSpace acc, T.drop 1 t) + | otherwise = findFieldName (T.take 1 t <> acc) $ T.drop 1 t + + parseFieldValue nm xs + | T.null bs = ([MIMEParam nm as], "") + | otherwise = let (zs,ys) = parseHeaders bs in (MIMEParam nm as :zs, ys) + where + (as,bs) = takeUntilCRLF xs + +parseMultipart :: Type -> T.Text -> (MIMEValue, T.Text) +parseMultipart mty body = + case lookupField "boundary" (paramPairs $ mimeParams mty) of + Nothing -> doTrace ("Multipart mime type, " ++ T.unpack (showType mty) ++ + ", has no required boundary parameter. Defaulting to text/plain") $ + (nullMIMEValue{ mime_val_type = defaultType + , mime_val_disp = Nothing + , mime_val_content = Single body + }, "") + Just bnd -> (nullMIMEValue { mime_val_type = mty + , mime_val_disp = Nothing + , mime_val_content = Multi vals + }, rs) + where (vals,rs) = splitMulti bnd body + +splitMulti :: T.Text -> T.Text -> ([MIMEValue], T.Text) +splitMulti bnd body_in = + -- Note: we insert a CRLF if it looks as if the boundary string starts + -- right off the bat. No harm done if this turns out to be incorrect. + let body | "--" `T.isPrefixOf` body_in = "\r\n" <> body_in + | otherwise = body_in + in case untilMatch dashBoundary body of + Nothing -> mempty + Just xs | "--" `T.isPrefixOf` xs -> ([], T.drop 2 xs) + | otherwise -> splitMulti1 (dropTrailer xs) + + where + dashBoundary = ("\r\n--" <> bnd) + + splitMulti1 xs + | T.null as && T.null bs = ([], "") + | T.null bs = ([parseMIMEMessage as],"") + | T.isPrefixOf "--" bs = ([parseMIMEMessage as], dropTrailer bs) + | otherwise = let (zs,ys) = splitMulti1 (dropTrailer bs) + in ((parseMIMEMessage as) : zs,ys) + + where + (as,bs) = matchUntil dashBoundary xs + + dropTrailer xs + | "\r\n" `T.isPrefixOf` xs1 = T.drop 2 xs1 + | otherwise = xs1 -- hmm, flag an error? + where + xs1 = T.dropWhile isHSpace xs + +parseMIMEType :: T.Text -> Maybe Type +parseMIMEType = parseContentType + +parseContentType :: T.Text -> Maybe Type +parseContentType str + | T.null minor0 = doTrace ("unable to parse content-type: " ++ show str) $ Nothing + | otherwise = Just Type { mimeType = toType maj as + , mimeParams = parseParams (T.dropWhile isHSpace bs) + } + where + (maj, minor0) = T.break (=='/') (dropFoldingWSP str) + minor = T.drop 1 minor0 + (as, bs) = T.break (\ ch -> isHSpace ch || isTSpecial ch) minor + toType a b = case lookupField (T.toLower a) mediaTypes of + Just ctor -> ctor b + _ -> Other a b + +parseParams :: T.Text -> [MIMEParam] +parseParams t | T.null t = [] + | ';' == T.head t = let (nm_raw, vs0) = T.break (=='=') (dropFoldingWSP $ T.tail t) + nm = T.toLower nm_raw in + if T.null vs0 + then [] + else let vs = T.tail vs0 in + if not (T.null vs) && T.head vs == '"' + then let vs1 = T.tail vs + (val, zs0) = T.break (=='"') vs1 in + if T.null zs0 + then [MIMEParam nm val] + else MIMEParam nm val : parseParams (T.dropWhile isHSpace $ T.tail zs0) + else let (val, zs) = T.break (\ch -> isHSpace ch || isTSpecial ch) vs in + MIMEParam nm val : parseParams (T.dropWhile isHSpace zs) + | otherwise = doTrace ("Codec.MIME.Parse.parseParams: curious param value -- " ++ show t) [] + +mediaTypes :: [(T.Text, T.Text -> MIMEType)] +mediaTypes = + [ ("multipart", (Multipart . toMultipart)) + , ("application", Application) + , ("audio", Audio) + , ("image", Image) + , ("message", Message) + , ("model", Model) + , ("text", Text) + , ("video", Video) + ] + where toMultipart b = fromMaybe other (lookupField (T.toLower b) multipartTypes) + where other | T.isPrefixOf "x-" b = Extension b + | otherwise = OtherMulti b + +multipartTypes :: [(T.Text, Multipart)] +multipartTypes = + [ ("alternative", Alternative) + , ("byteranges", Byteranges) + , ("digest", Digest) + , ("encrypted", Encrypted) + , ("form-data", FormData) + , ("mixed", Mixed) + , ("parallel", Parallel) + , ("related", Related) + , ("signed", Signed) + ] + +untilMatch :: T.Text -> T.Text -> Maybe T.Text +untilMatch a b | T.null a = Just b + | T.null b = Nothing + | a `T.isPrefixOf` b = Just $ T.drop (T.length a) b + | otherwise = untilMatch a $ T.tail b + +matchUntil :: T.Text -> T.Text -> (T.Text, T.Text) +-- searching str; returning parts before str and after str +matchUntil str = second (T.drop $ T.length str) . T.breakOn str + +{- +matchUntil' :: T.Text -> T.Text -> (T.Text, T.Text) +matchUntil' _ "" = ("", "") +matchUntil' str xs + | T.null xs = mempty + -- slow, but it'll do for now. + | str `T.isPrefixOf` xs = ("", T.drop (T.length str) xs) + | otherwise = let (as,bs) = matchUntil' str $ T.tail xs in (T.take 1 xs <> as, bs) +-} + +isHSpace :: Char -> Bool +isHSpace c = c == ' ' || c == '\t' + +isTSpecial :: Char -> Bool +isTSpecial x = x `elem` "()<>@,;:\\\"/[]?=" -- " + +dropFoldingWSP :: T.Text -> T.Text +dropFoldingWSP t | T.null t = "" + | isHSpace (T.head t) = dropFoldingWSP $ T.tail t + | "\r\n" `T.isPrefixOf` t && not (T.null $ T.drop 2 t) && isHSpace (T.head $ T.drop 2 t) + = dropFoldingWSP $ T.drop 3 t + | otherwise = t + +takeUntilCRLF :: T.Text -> (T.Text, T.Text) +takeUntilCRLF str = go "" str + where + go acc t | T.null t = (T.reverse (T.dropWhile isHSpace acc), "") + | "\r\n" `T.isPrefixOf` t && not (T.null $ T.drop 2 t) && isHSpace (T.head $ T.drop 2 t) + = go (" " <> acc) (T.drop 3 t) + | "\r\n" `T.isPrefixOf` t && not (T.null $ T.drop 2 t) + = (T.reverse (T.dropWhile isHSpace acc), T.drop 2 t) + | otherwise = go (T.take 1 t <> acc) $ T.tail t + +-- case in-sensitive lookup of field names or attributes\/parameters. +lookupField :: T.Text -> [(T.Text,a)] -> Maybe a +lookupField n ns = + -- assume that inputs have been mostly normalized already + -- (i.e., lower-cased), but should the lookup fail fall back + -- to a second try where we do normalize before giving up. + case lookup n ns of + x@Just{} -> x + Nothing -> + let nl = T.toLower n in + fmap snd $ L.find ((nl==) . T.toLower . fst) ns + diff --git a/Codec/MIME/QuotedPrintable.hs b/Codec/MIME/QuotedPrintable.hs new file mode 100644 index 0000000..cdc2266 --- /dev/null +++ b/Codec/MIME/QuotedPrintable.hs @@ -0,0 +1,66 @@ +-------------------------------------------------------------------- +-- | +-- Module : Codec.MIME.QuotedPrintable +-- Copyright : (c) 2006-2009, Galois, Inc. +-- License : BSD3 +-- +-- Maintainer: Sigbjorn Finne <sigbjorn.finne@gmail.com> +-- Stability : provisional +-- Portability: +-- +-- To and from QP content encoding. +-- +-------------------------------------------------------------------- +module Codec.MIME.QuotedPrintable + ( decode -- :: String -> String + , encode -- :: String -> String + ) where + +import Data.Char + +-- | 'decode' incoming quoted-printable content, stripping +-- out soft line breaks and translating @=XY@ sequences +-- into their decoded byte\/octet. The output encoding\/representation +-- is still a String, not a sequence of bytes. +decode :: String -> String +decode "" = "" +decode ('=':'\r':'\n':xs) = decode xs -- soft line break. +decode ('=':x1:x2:xs) + | isHexDigit x1 && isHexDigit x2 = + chr (digitToInt x1 * 16 + digitToInt x2) : decode xs +decode ('=':xs) = '=':decode xs + -- make it explicit that we propagate other '=' occurrences. +decode (x1:xs) = x1:decode xs + +-- | 'encode' converts a sequence of characeter _octets_ into +-- quoted-printable form; suitable for transmission in MIME +-- payloads. Note the stress on _octets_; it is assumed that +-- you have already converted Unicode into a <=8-bit encoding +-- (UTF-8, most likely.) +encode :: String -> String +encode xs = encodeLength 0 xs + +-- | @encodeLength llen str@ is the worker function during encoding. +-- The extra argument @llen@ tracks the current column for the line +-- being processed. Soft line breaks are inserted if a line exceeds +-- a max length. +encodeLength :: Int -> String -> String +encodeLength _ "" = "" +encodeLength n (x:xs) + | n >= 72 = '=':'\r':'\n':encodeLength 0 (x:xs) +encodeLength _ ('=':xs) + = '=':'3':'D':encodeLength 0 xs +encodeLength n (x:xs) + | ox >= 0x100 = error ("QuotedPrintable.encode: encountered > 8 bit character: " ++ show (x,ox)) + | n >= 72 = '=':'\r':'\n':encodeLength 0 (x:xs) + | ox >= 0x21 && ox <= 0x7e = x : encodeLength (n+1) xs + | ox == 0x09 || ox == 0x20 = x : encodeLength (n+1) xs + | otherwise = '=':showH (ox `div` 0x10): showH (ox `mod` 0x10):encodeLength (n+3) xs + where + ox = ord x + showH v + | v < 10 = chr (ord_0 + v) + | otherwise = chr (ord_A + (v-10)) + + ord_0 = ord '0' + ord_A = ord 'A' diff --git a/Codec/MIME/Type.hs b/Codec/MIME/Type.hs new file mode 100644 index 0000000..2ae9abd --- /dev/null +++ b/Codec/MIME/Type.hs @@ -0,0 +1,187 @@ +{-# LANGUAGE OverloadedStrings #-} +-------------------------------------------------------------------- +-- | +-- Module : Codec.MIME.Type +-- Copyright : (c) 2006-2009, Galois, Inc. +-- License : BSD3 +-- +-- Maintainer: Sigbjorn Finne <sigbjorn.finne@gmail.com> +-- Stability : provisional +-- Portability: portable +-- +-- +-- Representing MIME types and values. +-- +-------------------------------------------------------------------- +module Codec.MIME.Type where + +import qualified Data.Text as T +import Data.Monoid ((<>)) + +data MIMEParam = MIMEParam { paramName :: T.Text + , paramValue :: T.Text } + deriving (Show, Ord, Eq) + +data Type = Type + { mimeType :: MIMEType + , mimeParams :: [MIMEParam] + } deriving ( Show, Ord, Eq ) + +-- | The @null@ MIME record type value; currently a @text/plain@. +nullType :: Type +nullType = Type + { mimeType = Text "plain" + , mimeParams = [] + } + +showType :: Type -> T.Text +showType t = showMIMEType (mimeType t) <> showMIMEParams (mimeParams t) + +showMIMEParams :: [MIMEParam] -> T.Text +showMIMEParams ps = T.concat $ map showP ps + where + showP (MIMEParam a b) = "; " <> a <> "=\"" <> b <> "\"" + + +data MIMEType + = Application SubType + | Audio SubType + | Image SubType + | Message SubType + | Model SubType + | Multipart Multipart + | Text TextType + | Video SubType + | Other {otherType :: T.Text, otherSubType :: SubType} + deriving ( Show, Ord, Eq ) + +showMIMEType :: MIMEType -> T.Text +showMIMEType t = + case t of + Application s -> "application/"<>s + Audio s -> "audio/"<>s + Image s -> "image/"<>s + Message s -> "message/"<>s + Model s -> "model/"<>s + Multipart s -> "multipart/"<>showMultipart s + Text s -> "text/"<>s + Video s -> "video/"<>s + Other a b -> a <> "/" <> b + +-- | a (type, subtype) MIME pair. +data MIMEPair + = MIMEPair T.Text SubType + deriving ( Eq ) + +showMIMEPair :: MIMEPair -> T.Text +showMIMEPair (MIMEPair a b) = a <> "/" <> b + +-- | default subtype representation. +type SubType = T.Text + +-- | subtype for text content; currently just a string. +type TextType = SubType + +subTypeString :: Type -> T.Text +subTypeString t = T.drop 1 $ snd $ T.break (=='/') (showMIMEType (mimeType t)) + +majTypeString :: Type -> T.Text +majTypeString t = fst $ T.break (=='/') (showMIMEType (mimeType t)) + +data Multipart + = Alternative + | Byteranges + | Digest + | Encrypted + | FormData + | Mixed + | Parallel + | Related + | Signed + | Extension T.Text -- ^ e.g., 'x-foo' (i.e., includes the 'x-' bit) + | OtherMulti T.Text -- unrecognized\/uninterpreted. + -- (e.g., appledouble, voice-message, etc.) + deriving ( Show, Ord, Eq ) + +isXmlBased :: Type -> Bool +isXmlBased t = + case mimeType t of + Multipart{} -> False + _ -> "+xml" `T.isSuffixOf` subTypeString t + +isXmlType :: Type -> Bool +isXmlType t = isXmlBased t || + case mimeType t of + Application s -> s `elem` xml_media_types + Text s -> s `elem` xml_media_types + _ -> False + where + -- Note: xml-dtd isn't considered an XML type here. + xml_media_types :: [T.Text] + xml_media_types = + [ "xml" + , "xml-external-parsed-entity" + ] + + +showMultipart :: Multipart -> T.Text +showMultipart m = + case m of + Alternative -> "alternative" + Byteranges -> "byteranges" + Digest -> "digest" + Encrypted -> "encrypted" + FormData -> "form-data" + Mixed -> "mixed" + Parallel -> "parallel" + Related -> "related" + Signed -> "signed" + Extension e -> e + OtherMulti e -> e + +type Content = T.Text + +data MIMEValue = MIMEValue + { mime_val_type :: Type + , mime_val_disp :: Maybe Disposition + , mime_val_content :: MIMEContent + , mime_val_headers :: [MIMEParam] + , mime_val_inc_type :: Bool + } deriving ( Show, Eq ) + +nullMIMEValue :: MIMEValue +nullMIMEValue = MIMEValue + { mime_val_type = nullType + , mime_val_disp = Nothing + , mime_val_content = Multi [] + , mime_val_headers = [] + , mime_val_inc_type = True + } + +data MIMEContent + = Single Content + | Multi [MIMEValue] + deriving (Eq,Show) + +data Disposition + = Disposition + { dispType :: DispType + , dispParams :: [DispParam] + } deriving ( Show, Eq ) + +data DispType + = DispInline + | DispAttachment + | DispFormData + | DispOther T.Text + deriving ( Show, Eq) + +data DispParam + = Name T.Text + | Filename T.Text + | CreationDate T.Text + | ModDate T.Text + | ReadDate T.Text + | Size T.Text + | OtherParam T.Text T.Text + deriving ( Show, Eq) diff --git a/Codec/MIME/Utils.hs b/Codec/MIME/Utils.hs new file mode 100644 index 0000000..dd54860 --- /dev/null +++ b/Codec/MIME/Utils.hs @@ -0,0 +1,33 @@ +-------------------------------------------------------------------- +-- | +-- Module : Codec.MIME.Utils +-- Copyright : (c) 2006-2009, Galois, Inc. +-- License : BSD3 +-- +-- Maintainer: Sigbjorn Finne <sigbjorn.finne@gmail.com> +-- Stability : provisional +-- Portability: portable +-- +-- Extracting content from MIME values and types. +-- +-------------------------------------------------------------------- +module Codec.MIME.Utils + ( findMultipartNamed -- :: String -> MIMEValue -> Maybe MIMEValue + ) where + +import Codec.MIME.Type +import Data.List ( find ) +import Control.Monad ( msum ) +import Data.Text(Text) + +-- | Given a parameter name, locate it within a MIME value, +-- returning the corresponding (sub) MIME value. +findMultipartNamed :: Text -> MIMEValue -> Maybe MIMEValue +findMultipartNamed nm mv = + case mime_val_content mv of + Multi ms -> msum (map (findMultipartNamed nm) ms) + Single {} -> do cd <- mime_val_disp mv + _ <- find (withDispName nm) (dispParams cd) + return mv + where withDispName a (Name b) = a == b + withDispName _ _ = False |