@@ -1,170 +1,123 @@
1−{-# LANGUAGE BangPatterns #-}
21{-# LANGUAGE CPP #-}
3−{-# LANGUAGE OverloadedStrings #-}
4−{-# LANGUAGE PackageImports #-}
5−{-# LANGUAGE PatternGuards #-}
6−{-# LANGUAGE RecordWildCards #-}
72{-# LANGUAGE ScopedTypeVariables #-}
8−{-# LANGUAGE TupleSections #-}
9−{-# LANGUAGE ViewPatterns #-}
10−{-# OPTIONS_GHC -fno-warn-deprecations #-}
113
124module Network.Wai.Handler.Warp.Run where
135
14−import "iproute" Data.IP (toHostAddress, toHostAddress6)
15−import Control.Arrow (first)
16−import qualified Control.Concurrent as Conc (yield)
17−import Control.Exception as E
6+import Control.Concurrent (threadDelay, forkIOWithUnmask)
7+import Control.Exception
8+import Control.Monad (forever, when, unless, void)
9+import Control.Monad.IO.Class (MonadIO, liftIO)
10+import Control.Monad.Trans.Class (lift)
11+import Data.ByteString (ByteString)
1812import qualified Data.ByteString as S
19−import Data.Char (chr)
20−import Data.IORef (IORef, newIORef, readIORef, writeIORef)
21−import Data.Streaming.Network (bindPortTCP)
22−import Foreign.C.Error (Errno(..), eCONNABORTED)
23−import GHC.IO.Exception (IOException(..))
24−import qualified Network.HTTP2 as H2
25−import Network.Socket (Socket, close, accept, withSocketsDo, SockAddr(SockAddrInet, SockAddrInet6), setSocketOption, SocketOption(..))
26−#if MIN_VERSION_network(3,1,1)
27−import Network.Socket (gracefulClose)
28−#endif
13+import Data.Conduit
14+import Data.Conduit.Internal (ResumableSource (..))
15+import qualified Data.Conduit.List as CL
16+import Data.Conduit.Network (bindPort)
17+import Network (sClose, Socket)
18+import Network.Sendfile
19+import Network.Socket (accept, SockAddr)
2920import qualified Network.Socket.ByteString as Sock
3021import Network.Wai
31−import Network.Wai.Internal (ResponseReceived (ResponseReceived))
32−import System.Environment (lookupEnv)
33−import qualified System.TimeManager as T
34−import System.Timeout (timeout)
35−
36−import Network.Wai.Handler.Warp.Buffer
37−import Network.Wai.Handler.Warp.Counter
38−import qualified Network.Wai.Handler.Warp.Date as D
39−import qualified Network.Wai.Handler.Warp.FdCache as F
40−import qualified Network.Wai.Handler.Warp.FileInfoCache as I
41−import Network.Wai.Handler.Warp.HTTP2 (http2)
42−import Network.Wai.Handler.Warp.HTTP2.Types (isHTTP2)
43−import Network.Wai.Handler.Warp.Header
44−import Network.Wai.Handler.Warp.Imports hiding (readInt)
45−import Network.Wai.Handler.Warp.ReadInt
46−import Network.Wai.Handler.Warp.Recv
4722import Network.Wai.Handler.Warp.Request
4823import Network.Wai.Handler.Warp.Response
49−import Network.Wai.Handler.Warp.SendFile
5024import Network.Wai.Handler.Warp.Settings
25+import qualified Network.Wai.Handler.Warp.Timeout as T
5126import Network.Wai.Handler.Warp.Types
27+import Prelude hiding (catch)
5228
29+-- Sock.recv first tries to call recvfrom() optimistically.
30+-- If EAGAIN returns, it polls incoming data with epoll/kqueue.
31+-- This code first polls incoming data with epoll/kqueue.
5332
5433#if WINDOWS
55−import Network.Wai.Handler.Warp.Windows
34+import qualified Control.Concurrent.MVar as MV
35+import Network.Socket (withSocketsDo)
36+import Control.Concurrent (forkIO)
5637#else
38+import System.Posix.IO (FdOption(CloseOnExec), setFdOption)
5739import Network.Socket (fdSocket)
5840#endif
5941
60−-- | Creating 'Connection' for plain HTTP based on a given socket.
61−socketConnection :: Settings -> Socket -> IO Connection
62−#if MIN_VERSION_network(3,1,1)
63−socketConnection set s = do
64−#else
65−socketConnection _ s = do
42+#if SENDFILEFD
43+import Control.Applicative
44+import qualified Network.Wai.Handler.Warp.FdCache as F
6645#endif
67− bufferPool <- newBufferPool
68− writeBuf <- allocateBuffer bufferSize
69− let sendall = Sock.sendAll s
70− isH2 <- newIORef False -- HTTP/1.x
71− return Connection {
72− connSendMany = Sock.sendMany s
73− , connSendAll = sendall
74− , connSendFile = sendFile s writeBuf bufferSize sendall
75−#if MIN_VERSION_network(3,1,1)
76− , connClose = do
77− h2 <- readIORef isH2
78− let tm = if h2 then settingsGracefulCloseTimeout2 set
79− else settingsGracefulCloseTimeout1 set
80− if tm == 0 then
81− close s
82− else
83− gracefulClose s tm `E.catch` \(E.SomeException _) -> return ()
46+
47+-- FIXME come up with good values here
48+bytesPerRead :: Int
49+bytesPerRead = 4096
50+
51+-- | Default action value for 'Connection'
52+socketConnection :: Socket -> Connection
53+socketConnection s = Connection
54+ { connSendMany = Sock.sendMany s
55+ , connSendAll = Sock.sendAll s
56+ , connSendFile = sendFile s
57+ , connClose = sClose s
58+ , connRecv = Sock.recv s bytesPerRead
59+ }
60+
61+sendFile :: Socket -> FilePath -> Integer -> Integer -> IO () -> [ByteString] -> Cleaner -> IO ()
62+#if SENDFILEFD
63+sendFile s path off len act hdr cleaner = case fdCacher cleaner of
64+ Nothing -> sendfileWithHeader s path (PartOfFile off len) act hdr
65+ Just fdc -> do
66+ (fd, fresher) <- F.getFd fdc path
67+ sendfileFdWithHeader s fd (PartOfFile off len) (act>>fresher) hdr
8468#else
85− , connClose = close s
69+sendFile s path off len act hdr _ =
70+ sendfileWithHeader s path (PartOfFile off len) act hdr
71+#endif
72+
73+#if __GLASGOW_HASKELL__ < 702
74+allowInterrupt :: IO ()
75+allowInterrupt = unblock $ return ()
8676#endif
87− , connFree = freeBuffer writeBuf
88− , connRecv = receive s bufferPool
89− , connRecvBuf = receiveBuf s
90− , connWriteBuffer = writeBuf
91− , connBufferSize = bufferSize
92− , connHTTP2 = isH2
93− }
9477
95−-- | Run an 'Application' on the given port.
96−-- This calls 'runSettings' with 'defaultSettings'.
78+-- | Run an 'Application' on the given port. This calls 'runSettings' with
79+-- 'defaultSettings'.
9780run :: Port -> Application -> IO ()
9881run p = runSettings defaultSettings { settingsPort = p }
9982
100−-- | Run an 'Application' on the port present in the @PORT@
101−-- environment variable. Uses the 'Port' given when the variable is unset.
102−-- This calls 'runSettings' with 'defaultSettings'.
103−--
104−-- Since 3.0.9
105−runEnv :: Port -> Application -> IO ()
106−runEnv p app = do
107− mp <- lookupEnv "PORT"
108−
109− maybe (run p app) runReadPort mp
110−
111− where
112− runReadPort :: String -> IO ()
113− runReadPort sp = case reads sp of
114− ((p', _):_) -> run p' app
115− _ -> fail $ "Invalid value in $PORT: " ++ sp
116−
117−-- | Run an 'Application' with the given 'Settings'.
118−-- This opens a listen socket on the port defined in 'Settings' and
119−-- calls 'runSettingsSocket'.
83+-- | Run a Warp server with the given settings.
12084runSettings :: Settings -> Application -> IO ()
121−runSettings set app = withSocketsDo $
85+#if WINDOWS
86+runSettings set app = withSocketsDo $ do
87+ var <- MV.newMVar Nothing
88+ let clean = MV.modifyMVar_ var $ \s -> maybe (return ()) sClose s >> return Nothing
89+ void . forkIO $ bracket
90+ (bindPort (settingsPort set) (settingsHost set))
91+ (const clean)
92+ (\s -> do
93+ MV.modifyMVar_ var (\_ -> return $ Just s)
94+ runSettingsSocket set s app)
95+ forever (threadDelay maxBound) `finally` clean
96+#else
97+runSettings set app =
12298 bracket
123− (bindPortTCP (settingsPort set) (settingsHost set))
124− close
99+ (bindPort (settingsPort set) (settingsHost set))
100+ sClose
125101 (\socket -> do
126102 setSocketCloseOnExec socket
127103 runSettingsSocket set socket app)
104+#endif
128105
129−-- | This installs a shutdown handler for the given socket and
130−-- calls 'runSettingsConnection' with the default connection setup action
131−-- which handles plain (non-cipher) HTTP.
132−-- When the listen socket in the second argument is closed, all live
133−-- connections are gracefully shut down.
134−--
135−-- The supplied socket can be a Unix named socket, which
106+-- | Same as 'runSettings', but uses a user-supplied socket instead of opening
107+-- one. This allows the user to provide, for example, Unix named socket, which
136108-- can be used when reverse HTTP proxying into your application.
137109--
138110-- Note that the 'settingsPort' will still be passed to 'Application's via the
139111-- 'serverPort' record.
140112runSettingsSocket :: Settings -> Socket -> Application -> IO ()
141−runSettingsSocket set socket app = do
142− settingsInstallShutdownHandler set closeListenSocket
143− runSettingsConnection set getConn app
113+runSettingsSocket set socket app =
114+ runSettingsConnection set getter app
144115 where
145− getConn = do
146−#if WINDOWS
147− (s, sa) <- windowsThreadBlockHack $ accept socket
148−#else
149− (s, sa) <- accept socket
150−#endif
151− setSocketCloseOnExec s
152− -- NoDelay causes an error for AF_UNIX.
153− setSocketOption s NoDelay 1 `E.catch` \(E.SomeException _) -> return ()
154− conn <- socketConnection set s
155− return (conn, sa)
156−
157− closeListenSocket = close socket
116+ getter = do
117+ (conn, sa) <- accept socket
118+ setSocketCloseOnExec socket
119+ return (socketConnection conn, sa)
158120
159−-- | The connection setup action would be expensive. A good example
160−-- is initialization of TLS.
161−-- So, this converts the connection setup action to the connection maker
162−-- which will be executed after forking a new worker thread.
163−-- Then this calls 'runSettingsConnectionMaker' with the connection maker.
164−-- This allows the expensive computations to be performed
165−-- in a separate worker thread instead of the main server loop.
166−--
167−-- Since 1.3.5
168121runSettingsConnection :: Settings -> IO (Connection, SockAddr) -> Application -> IO ()
169122runSettingsConnection set getConn app = runSettingsConnectionMaker set getConnMaker app
170123 where
@@ -172,428 +125,158 @@ runSettingsConnection set getConn app = runSettingsConnectionMaker set getConnMa
172125 (conn, sa) <- getConn
173126 return (return conn, sa)
174127
175−-- | This modifies the connection maker so that it returns 'TCP' for 'Transport'
176−-- (i.e. plain HTTP) then calls 'runSettingsConnectionMakerSecure'.
177−runSettingsConnectionMaker :: Settings -> IO (IO Connection, SockAddr) -> Application -> IO ()
178−runSettingsConnectionMaker x y =
179− runSettingsConnectionMakerSecure x (toTCP <$> y)
180− where
181− toTCP = first ((, TCP) <$>)
182−
183−----------------------------------------------------------------
184−
185−-- | The core run function which takes 'Settings',
186−-- a connection maker and 'Application'.
187−-- The connection maker can return a connection of either plain HTTP
188−-- or HTTP over TLS.
128+-- | Allows you to provide a function which will return a @Connection@. In
129+-- cases where creating the @Connection@ can be expensive, this allows the
130+-- expensive computations to be performed in a separate thread instead of the
131+-- main server loop.
189132--
190−-- Since 2.1.4
191−runSettingsConnectionMakerSecure :: Settings -> IO (IO (Connection, Transport), SockAddr) -> Application -> IO ()
192−runSettingsConnectionMakerSecure set getConnMaker app = do
133+-- Since 1.3.5
134+runSettingsConnectionMaker :: Settings -> IO (IO Connection, SockAddr) -> Application -> IO ()
135+runSettingsConnectionMaker set getConn app = do
136+#if SENDFILEFD
137+ let duration = settingsFdCacheDuration set
138+ fc <- case duration of
139+ 0 -> return Nothing
140+ _ -> Just <$> F.initialize (duration * 1000000)
141+#endif
193142 settingsBeforeMainLoop set
194− counter <- newCounter
195− withII $ acceptConnection set getConnMaker app counter
196− where
197− withII action =
198− withTimeoutManager $ \tm ->
199− D.withDateCache $ \dc ->
200− F.withFdCache fdCacheDurationInSeconds $ \fdc ->
201− I.withFileInfoCache fdFileInfoDurationInSeconds $ \fic -> do
202− let ii = InternalInfo tm dc fdc fic
203− action ii
204−
205− !fdCacheDurationInSeconds = settingsFdCacheDuration set * 1000000
206− !fdFileInfoDurationInSeconds = settingsFileInfoCacheDuration set * 1000000
207− !timeoutInSeconds = settingsTimeout set * 1000000
208− withTimeoutManager f = case settingsManager set of
209− Just tm -> f tm
210− Nothing -> bracket
211− (T.initialize timeoutInSeconds)
212− T.stopManager
213− f
214143
215−-- Note that there is a thorough discussion of the exception safety of the
216−-- following code at: https://github.com/yesodweb/wai/issues/146
217−--
218−-- We need to make sure of two things:
219−--
220−-- 1. Asynchronous exceptions are not blocked entirely in the main loop.
221−-- Doing so would make it impossible to kill the Warp thread.
222−--
223−-- 2. Once a connection maker is received via acceptNewConnection, the
224−-- connection is guaranteed to be closed, even in the presence of
225−-- async exceptions.
226−--
227−-- Our approach is explained in the comments below.
228−acceptConnection :: Settings
229− -> IO (IO (Connection, Transport), SockAddr)
230− -> Application
231− -> Counter
232− -> InternalInfo
233− -> IO ()
234−acceptConnection set getConnMaker app counter ii = do
235− -- First mask all exceptions in acceptLoop. This is necessary to
236− -- ensure that no async exception is throw between the call to
237− -- acceptNewConnection and the registering of connClose.
144+ -- Note that there is a thorough discussion of the exception safety of the
145+ -- following code at: https://github.com/yesodweb/wai/issues/146
238146 --
239− -- acceptLoop can be broken by closing the listing socket.
240− void $ mask_ acceptLoop
241− -- In some cases, we want to stop Warp here without graceful shutdown.
242− -- So, async exceptions are allowed here.
243− -- That's why `finally` is not used.
244− gracefulShutdown set counter
245− where
246− acceptLoop = do
147+ -- We need to make sure of two things:
148+ --
149+ -- 1. Asynchronous exceptions are not blocked entirely in the main loop.
150+ -- Doing so would make it impossible to kill the Warp thread.
151+ --
152+ -- 2. Once a connection maker is received via getConnLoop, the connection
153+ -- is guaranteed to be closed, even in the presence of async exceptions.
154+ --
155+ -- Our approach is explained in the comments below.
156+
157+ -- First mask all exceptions in the main loop. This is necessary to ensure
158+ -- that no async exception is throw between the call to getConnLoop and the
159+ -- registering of connClose.
160+ withTimeoutManager $ \tm -> mask_ . forever $ do
247161 -- Allow async exceptions before receiving the next connection maker.
248162 allowInterrupt
249163
250− -- acceptNewConnection will try to receive the next incoming
251− -- request. It returns a /connection maker/, not a connection,
252− -- since in some circumstances creating a working connection
253− -- from a raw socket may be an expensive operation, and this
254− -- expensive work should not be performed in the main event
255− -- loop. An example of something expensive would be TLS
256− -- negotiation.
257− mx <- acceptNewConnection
258− case mx of
259− Nothing -> return ()
260− Just (mkConn, addr) -> do
261− fork set mkConn addr app counter ii
262− acceptLoop
263−
264− acceptNewConnection = do
265− ex <- try getConnMaker
266− case ex of
267− Right x -> return $ Just x
268− Left e -> do
269− let eConnAborted = getErrno eCONNABORTED
270− getErrno (Errno cInt) = cInt
271− if ioe_errno e == Just eConnAborted
272− then acceptNewConnection
273− else do
274− settingsOnException set Nothing $ toException e
275− return Nothing
276−
277−-- Fork a new worker thread for this connection maker, and ask for a
278−-- function to unmask (i.e., allow async exceptions to be thrown).
279−fork :: Settings
280− -> IO (Connection, Transport)
281− -> SockAddr
282− -> Application
283− -> Counter
284− -> InternalInfo
285− -> IO ()
286−fork set mkConn addr app counter ii = settingsFork set $ \unmask ->
287− -- Call the user-supplied on exception code if any
288− -- exceptions are thrown.
289− handle (settingsOnException set Nothing) $
290− -- Run the connection maker to get a new connection, and ensure
291− -- that the connection is closed. If the mkConn call throws an
292− -- exception, we will leak the connection. If the mkConn call is
293− -- vulnerable to attacks (e.g., Slowloris), we do nothing to
294− -- protect the server. It is therefore vital that mkConn is well
295− -- vetted.
296− --
297− -- We grab the connection before registering timeouts since the
298− -- timeouts will be useless during connection creation, due to the
299− -- fact that async exceptions are still masked.
300− bracket mkConn cleanUp (serve unmask)
301− where
302− cleanUp (conn, _) = connClose conn `finally` connFree conn
303−
304− -- We need to register a timeout handler for this thread, and
305− -- cancel that handler as soon as we exit.
306− serve unmask (conn, transport) = bracket register cancel $ \th -> do
307− -- We now have fully registered a connection close handler in
308− -- the case of all exceptions, so it is safe to once again
309− -- allow async exceptions.
310− unmask .
311− -- Call the user-supplied code for connection open and
312− -- close events
313− bracket (onOpen addr) (onClose addr) $ \goingon ->
314− -- Actually serve this connection. bracket with closeConn
315− -- above ensures the connection is closed.
316− when goingon $ serveConnection conn ii th addr transport set app
317− where
318− register = T.registerKillThread (timeoutManager ii) (connClose conn)
319− cancel = T.cancel
320−
321− onOpen adr = increase counter >> settingsOnOpen set adr
322− onClose adr _ = decrease counter >> settingsOnClose set adr
323−
324−serveConnection :: Connection
325− -> InternalInfo
326− -> T.Handle
327− -> SockAddr
328− -> Transport
329− -> Settings
330− -> Application
331− -> IO ()
332−serveConnection conn ii th origAddr transport settings app = do
333− -- fixme: Upgrading to HTTP/2 should be supported.
334− (h2,bs) <- if isHTTP2 transport then
335− return (True, "")
336− else do
337− bs0 <- connRecv conn
338− if S.length bs0 >= 4 && "PRI " `S.isPrefixOf` bs0 then
339− return (True, bs0)
340− else
341− return (False, bs0)
342− istatus <- newIORef False
343− if settingsHTTP2Enabled settings && h2 then do
344− rawRecvN <- makeReceiveN bs (connRecv conn) (connRecvBuf conn)
345− -- This thread becomes the sender in http2 library.
346− -- In the case of event source, one request comes and one
347− -- worker gets busy. But it is likely that the receiver does
348− -- not receive any data at all while the sender is sending
349− -- output data from the worker. It's not good enough to tickle
350− -- the time handler in the receiver only. So, we should tickle
351− -- the time handler in both the receiver and the sender.
352− let recvN = wrappedRecvN th istatus (settingsSlowlorisSize settings) rawRecvN
353− sendBS x = connSendAll conn x >> T.tickle th
354− -- fixme: origAddr
355− checkTLS
356− setConnHTTP2 conn True
357− http2 conn transport ii origAddr settings recvN sendBS app
358− else do
359− src <- mkSource (wrappedRecv conn th istatus (settingsSlowlorisSize settings))
360− writeIORef istatus True
361− leftoverSource src bs
362− addr <- getProxyProtocolAddr src
363− http1 True addr istatus src `E.catch` \e ->
364− case () of
365− ()
366− -- See comment below referencing
367− -- https://github.com/yesodweb/wai/issues/618
368− | Just NoKeepAliveRequest <- fromException e -> return ()
369− -- No valid request
370− | Just (BadFirstLine _) <- fromException e -> return ()
371− | otherwise -> do
372− _ <- sendErrorResponse (dummyreq addr) istatus e
373− throwIO e
374−
375− where
376− getProxyProtocolAddr src =
377− case settingsProxyProtocol settings of
378− ProxyProtocolNone ->
379− return origAddr
380− ProxyProtocolRequired -> do
381− seg <- readSource src
382− parseProxyProtocolHeader src seg
383− ProxyProtocolOptional -> do
384− seg <- readSource src
385− if S.isPrefixOf "PROXY " seg
386− then parseProxyProtocolHeader src seg
387− else do leftoverSource src seg
388− return origAddr
389−
390− parseProxyProtocolHeader src seg = do
391− let (header,seg') = S.break (== 0x0d) seg -- 0x0d == CR
392− maybeAddr = case S.split 0x20 header of -- 0x20 == space
393− ["PROXY","TCP4",clientAddr,_,clientPort,_] ->
394− case [x | (x, t) <- reads (decodeAscii clientAddr), null t] of
395− [a] -> Just (SockAddrInet (readInt clientPort)
396− (toHostAddress a))
397− _ -> Nothing
398− ["PROXY","TCP6",clientAddr,_,clientPort,_] ->
399− case [x | (x, t) <- reads (decodeAscii clientAddr), null t] of
400− [a] -> Just (SockAddrInet6 (readInt clientPort)
401− 0
402− (toHostAddress6 a)
403− 0)
404− _ -> Nothing
405− ("PROXY":"UNKNOWN":_) ->
406− Just origAddr
407− _ ->
408− Nothing
409− case maybeAddr of
410− Nothing -> throwIO (BadProxyHeader (decodeAscii header))
411− Just a -> do leftoverSource src (S.drop 2 seg') -- drop CRLF
412− return a
413−
414− decodeAscii = map (chr . fromEnum) . S.unpack
415−
416− shouldSendErrorResponse se
417− | Just ConnectionClosedByPeer <- fromException se = False
418− | otherwise = True
419−
420− sendErrorResponse req istatus e = do
421− status <- readIORef istatus
422− if shouldSendErrorResponse e && status
423− then do
424− sendResponse settings conn ii th req defaultIndexRequestHeader (return S.empty) (errorResponse e)
425− else return False
426−
427− dummyreq addr = defaultRequest { remoteHost = addr }
428−
429− errorResponse e = settingsOnExceptionResponse settings e
430−
431− http1 firstRequest addr istatus src = do
432− (req, mremainingRef, idxhdr, nextBodyFlush) <- recvRequest firstRequest settings conn ii th addr src transport
433− keepAlive <- processRequest istatus src req mremainingRef idxhdr nextBodyFlush
434− `E.catch` \e -> do
435− settingsOnException settings (Just req) e
436− -- Don't throw the error again to prevent calling settingsOnException twice.
437− return False
438−
439− -- When doing a keep-alive connection, the other side may just
440− -- close the connection. We don't want to treat that as an
441− -- exceptional situation, so we pass in False to http1 (which
442− -- in turn passes in False to recvRequest), indicating that
443− -- this is not the first request. If, when trying to read the
444− -- request headers, no data is available, recvRequest will
445− -- throw a NoKeepAliveRequest exception, which we catch here
446− -- and ignore. See: https://github.com/yesodweb/wai/issues/618
447− when keepAlive $ http1 False addr istatus src
448−
449− processRequest istatus src req mremainingRef idxhdr nextBodyFlush = do
450− -- Let the application run for as long as it wants
451− T.pause th
452−
453− -- In the event that some scarce resource was acquired during
454− -- creating the request, we need to make sure that we don't get
455− -- an async exception before calling the ResponseSource.
456− keepAliveRef <- newIORef $ error "keepAliveRef not filled"
457− r <- E.try $ app req $ \res -> do
458− T.resume th
459− -- FIXME consider forcing evaluation of the res here to
460− -- send more meaningful error messages to the user.
461− -- However, it may affect performance.
462− writeIORef istatus False
463− keepAlive <- sendResponse settings conn ii th req idxhdr (readSource src) res
464− writeIORef keepAliveRef keepAlive
465− return ResponseReceived
466− case r of
467− Right ResponseReceived -> return ()
468− Left e@(SomeException _)
469− | Just (ExceptionInsideResponseBody e') <- fromException e -> throwIO e'
470− | otherwise -> do
471− keepAlive <- sendErrorResponse req istatus e
472− settingsOnException settings (Just req) e
473− writeIORef keepAliveRef keepAlive
474−
475− keepAlive <- readIORef keepAliveRef
476−
477− -- We just send a Response and it takes a time to
478− -- receive a Request again. If we immediately call recv,
479− -- it is likely to fail and cause the IO manager to do some work.
480− -- It is very costly, so we yield to another Haskell
481− -- thread hoping that the next Request will arrive
482− -- when this Haskell thread will be re-scheduled.
483− -- This improves performance at least when
484− -- the number of cores is small.
485− Conc.yield
486−
487− if keepAlive
488− then
489− -- If there is an unknown or large amount of data to still be read
490− -- from the request body, simple drop this connection instead of
491− -- reading it all in to satisfy a keep-alive request.
492− case settingsMaximumBodyFlush settings of
493− Nothing -> do
494− flushEntireBody nextBodyFlush
495− T.resume th
496− return True
497− Just maxToRead -> do
498− let tryKeepAlive = do
499− -- flush the rest of the request body
500− isComplete <- flushBody nextBodyFlush maxToRead
501− if isComplete then do
502− T.resume th
503− return True
504− else
505− return False
506− case mremainingRef of
507− Just ref -> do
508− remaining <- readIORef ref
509− if remaining <= maxToRead then
510− tryKeepAlive
511− else
512− return False
513− Nothing -> tryKeepAlive
514− else
515− return False
516−
517− checkTLS = case transport of
518− TCP -> return () -- direct
519− tls -> unless (tls12orLater tls) $ goaway conn H2.InadequateSecurity "Weak TLS"
520− tls12orLater tls = tlsMajorVersion tls == 3 && tlsMinorVersion tls >= 3
521−
522−-- connClose must not be called here since Run:fork calls it
523−goaway :: Connection -> H2.ErrorCodeId -> ByteString -> IO ()
524−goaway Connection{..} etype debugmsg = connSendAll bytestream
164+ -- getConnLoop will try to receive the next incoming request. It
165+ -- returns a /connection maker/, not a connection, since in some
166+ -- circumstances creating a working connection from a raw socket may be
167+ -- an expensive operation, and this expensive work should not be
168+ -- performed in the main event loop. An example of something expensive
169+ -- would be TLS negotiation.
170+ (mkConn, addr) <- getConnLoop
171+
172+ -- Fork a new worker thread for this connection maker, and ask for a
173+ -- function to unmask (i.e., allow async exceptions to be thrown).
174+ void . forkIOWithUnmask $ \unmask ->
175+ -- Run the connection maker to get a new connection, and ensure
176+ -- that the connection is closed. If the mkConn call throws an
177+ -- exception, we will leak the connection. If the mkConn call is
178+ -- vulnerable to attacks (e.g., Slowloris), we do nothing to
179+ -- protect the server. It is therefore vital that mkConn is well
180+ -- vetted.
181+ --
182+ -- We grab the connection before registering timeouts since the
183+ -- timeouts will be useless during connection creation, due to the
184+ -- fact that async exceptions are still masked.
185+ bracket mkConn connClose $ \conn ->
186+
187+ -- We need to register a timeout handler for this thread, and
188+ -- cancel that handler as soon as we exit.
189+ bracket (T.registerKillThread tm) T.cancel $ \th ->
190+#if SENDFILEFD
191+ let cleaner = Cleaner th fc
192+#else
193+ let cleaner = Cleaner th
194+#endif
195+ -- We now have fully registered a connection close handler
196+ -- in the case of all exceptions, so it is safe to one
197+ -- again allow async exceptions.
198+ in unmask .
199+ -- Call the user-supplied on exception code if any
200+ -- exceptions are thrown.
201+ handle onE .
202+
203+ -- Call the user-supplied code for connection open and close events
204+ bracket_ onOpen onClose $
205+
206+ -- Actually serve this connection.
207+ serveConnection set cleaner port app conn addr
525208 where
526− einfo = H2.encodeInfo id 0
527− frame = H2.GoAwayFrame 0 etype debugmsg
528− bytestream = H2.encodeFrame einfo frame
529−
530−flushEntireBody :: IO ByteString -> IO ()
531−flushEntireBody src =
532− loop
209+ -- FIXME: only IOEception is caught. What about other exceptions?
210+ getConnLoop = getConn `catch` \(e :: IOException) -> do
211+ onE (toException e)
212+ -- "resource exhausted (Too many open files)" may happen by accept().
213+ -- Wait a second hoping that resource will be available.
214+ threadDelay 1000000
215+ getConnLoop
216+ onE = settingsOnException set
217+ port = settingsPort set
218+ onOpen = settingsOnOpen set
219+ onClose = settingsOnClose set
220+
221+ withTimeoutManager f =
222+ case settingsManager set of
223+ Nothing -> bracket
224+ (T.initialize $ settingsTimeout set * 1000000)
225+ T.stopManager
226+ f
227+ Just tm -> f tm
228+
229+serveConnection :: Settings
230+ -> Cleaner
231+ -> Port -> Application -> Connection -> SockAddr-> IO ()
232+serveConnection settings cleaner port app conn remoteHost' =
233+ runResourceT serveConnection'
533234 where
534− loop = do
535− bs <- src
536− unless (S.null bs) loop
537−
538−flushBody :: IO ByteString -- ^ get next chunk
539− -> Int -- ^ maximum to flush
540− -> IO Bool -- ^ True == flushed the entire body, False == we didn't
541−flushBody src =
542− loop
235+ innerRunResourceT
236+ | settingsResourceTPerRequest settings = lift . runResourceT
237+ | otherwise = id
238+ th = threadHandle cleaner
239+
240+ serveConnection' :: ResourceT IO ()
241+ serveConnection' = serveConnection'' $ connSource conn th
242+
243+ serveConnection'' fromClient = do
244+ (env, getSource) <- parseRequest conn port remoteHost' fromClient
245+ case settingsIntercept settings env of
246+ Nothing -> do
247+ -- Let the application run for as long as it wants
248+ liftIO $ T.pause th
249+ keepAlive <- innerRunResourceT $ do
250+ res <- app env
251+
252+ liftIO $ T.resume th
253+ sendResponse settings cleaner env conn res
254+
255+ -- flush the rest of the request body
256+ requestBody env $$ CL.sinkNull
257+ ResumableSource fromClient' _ <- liftIO getSource
258+
259+ when keepAlive $ serveConnection'' fromClient'
260+ Just intercept -> do
261+ liftIO $ T.pause th
262+ ResumableSource fromClient' _ <- liftIO getSource
263+ intercept fromClient' conn
264+
265+connSource :: Connection -> T.Handle -> Source (ResourceT IO) ByteString
266+connSource Connection { connRecv = recv } th = src
543267 where
544− loop toRead = do
545− bs <- src
546− let toRead' = toRead - S.length bs
547− case () of
548− ()
549− | S.null bs -> return True
550− | toRead' >= 0 -> loop toRead'
551− | otherwise -> return False
552−
553−wrappedRecv :: Connection -> T.Handle -> IORef Bool -> Int -> IO ByteString
554−wrappedRecv Connection { connRecv = recv } th istatus slowlorisSize = do
555− bs <- recv
556− unless (S.null bs) $ do
557− writeIORef istatus True
558− when (S.length bs >= slowlorisSize) $ T.tickle th
559− return bs
268+ src = do
269+ bs <- liftIO recv
270+ unless (S.null bs) $ do
271+ when (S.length bs >= 2048) $ liftIO $ T.tickle th
272+ yield bs
273+ src
560274
561−wrappedRecvN :: T.Handle -> IORef Bool -> Int -> (BufSize -> IO ByteString) -> (BufSize -> IO ByteString)
562−wrappedRecvN th istatus slowlorisSize readN bufsize = do
563− bs <- readN bufsize
564− unless (S.null bs) $ do
565− writeIORef istatus True
566− -- TODO: think about the slowloris protection in HTTP2: current code
567− -- might open a slow-loris attack vector. Rather than timing we should
568− -- consider limiting the per-client connections assuming that in HTTP2
569− -- we should allow only few connections per host (real-world
570− -- deployments with large NATs may be trickier).
571− when (S.length bs >= slowlorisSize || bufsize <= slowlorisSize) $ T.tickle th
572− return bs
573−
574−-- | Set flag FileCloseOnExec flag on a socket (on Unix)
575−--
576275-- Copied from: https://github.com/mzero/plush/blob/master/src/Plush/Server/Warp.hs
577−--
578−-- @since 3.2.17
579276setSocketCloseOnExec :: Socket -> IO ()
580277#if WINDOWS
581278setSocketCloseOnExec _ = return ()
582279#else
583−setSocketCloseOnExec socket = do
584−#if MIN_VERSION_network(3,0,0)
585− fd <- fdSocket socket
586−#else
587− let fd = fdSocket socket
280+setSocketCloseOnExec socket =
281+ setFdOption (fromIntegral $ fdSocket socket) CloseOnExec True
588282#endif
589− F.setFileCloseOnExec $ fromIntegral fd
590−#endif
591−
592−gracefulShutdown :: Settings -> Counter -> IO ()
593−gracefulShutdown set counter =
594− case settingsGracefulShutdownTimeout set of
595− Nothing ->
596− waitForZero counter
597− (Just seconds) ->
598− void (timeout (seconds * microsPerSecond) (waitForZero counter))
599− where microsPerSecond = 1000000