diff --git a/ChangeLog.md b/ChangeLog.md --- a/ChangeLog.md +++ b/ChangeLog.md @@ -1,3 +1,13 @@ +## 3.0.10 + +* Fix [missing `IORef` tweak](https://github.com/yesodweb/wai/issues/351) +* Disable timeouts as soon as request body is fully consumed. This addresses + the common case of a non-chunked request body. Previously, we would wait + until a zero-length `ByteString` is returned, but that is suboptimal for some + cases. For more information, see [issue + 351](https://github.com/yesodweb/wai/issues/351). +* Add `pauseTimeout` function + ## 3.0.9.3 * Don't serve a 416 status code for 0-length files [keter issue #75](https://github.com/snoyberg/keter/issues/75) diff --git a/Network/Wai/Handler/Warp.hs b/Network/Wai/Handler/Warp.hs --- a/Network/Wai/Handler/Warp.hs +++ b/Network/Wai/Handler/Warp.hs @@ -17,6 +17,21 @@ --------------------------------------------------------- -- | A fast, light-weight HTTP server handler for WAI. +-- +-- Note on slowloris timeouts: to prevent slowloris attacks, timeouts are used +-- at various points in request receiving and response sending. One interesting +-- corner case is partial request body consumption; in that case, Warp's +-- timeout handling is still in effect, and the timeout will not be triggered +-- again. Therefore, it is recommended that once you start consuming the +-- request body, you either: +-- +-- * consume the entire body promptly +-- +-- * call the 'pauseTimeout' function +-- +-- For more information, see . +-- +-- module Network.Wai.Handler.Warp ( -- * Run a Warp server run @@ -73,6 +88,8 @@ , Port , InvalidRequest (..) , ConnSendFileOverride (..) + -- * Per-request utilities + , pauseTimeout -- * Connection , Connection (..) , socketConnection @@ -105,10 +122,12 @@ import Network.Wai.Handler.Warp.Timeout import Network.Wai.Handler.Warp.Types import Control.Exception (SomeException) -import Network.Wai (Request, Response) +import Network.Wai (Request, Response, vault) import Network.Socket (SockAddr) import Data.Streaming.Network (HostPreference) import Data.ByteString (ByteString) +import qualified Data.Vault.Lazy as Vault +import Data.Maybe (fromMaybe) -- | Port to listen on. Default value: 3000 -- @@ -284,3 +303,12 @@ -- Since 3.0.5 setProxyProtocolOptional :: Settings -> Settings setProxyProtocolOptional y = y { settingsProxyProtocol = ProxyProtocolOptional } + +-- | Explicitly pause the slowloris timeout. +-- +-- This is useful for cases where you partially consume a request body. For +-- more information, see +-- +-- Since 3.0.10 +pauseTimeout :: Request -> IO () +pauseTimeout = fromMaybe (return ()) . Vault.lookup pauseTimeoutKey . vault diff --git a/Network/Wai/Handler/Warp/Request.hs b/Network/Wai/Handler/Warp/Request.hs --- a/Network/Wai/Handler/Warp/Request.hs +++ b/Network/Wai/Handler/Warp/Request.hs @@ -6,6 +6,7 @@ module Network.Wai.Handler.Warp.Request ( recvRequest , headerLines + , pauseTimeoutKey ) where import qualified Control.Concurrent as Conc (yield) @@ -16,7 +17,6 @@ import qualified Data.ByteString.Unsafe as SU import qualified Data.CaseInsensitive as CI import qualified Data.IORef as I -import Data.Monoid (mempty) import qualified Network.HTTP.Types as H import Network.Socket (SockAddr) import Network.Wai @@ -30,6 +30,8 @@ import Network.Wai.Internal import Prelude hiding (lines) import Control.Monad (when) +import qualified Data.Vault.Lazy as Vault +import System.IO.Unsafe (unsafePerformIO) ---------------------------------------------------------------- @@ -62,7 +64,7 @@ te = idxhdr ! idxTransferEncoding handleExpect conn httpversion expect (rbody, remainingRef, bodyLength) <- bodyAndSource src cl te - rbody' <- timeoutBody th rbody + rbody' <- timeoutBody remainingRef th rbody let req = Request { requestMethod = method , httpVersion = httpversion @@ -74,7 +76,9 @@ , isSecure = False , remoteHost = addr , requestBody = rbody' - , vault = mempty + , vault = Vault.insert pauseTimeoutKey + (Timeout.pause th) + Vault.empty , requestBodyLength = bodyLength , requestHeaderHost = idxhdr ! idxHost , requestHeaderRange = idxhdr ! idxRange @@ -138,18 +142,31 @@ ---------------------------------------------------------------- -timeoutBody :: Timeout.Handle -> IO ByteString -> IO (IO ByteString) -timeoutBody timeoutHandle rbody = do +timeoutBody :: Maybe (I.IORef Int) -- ^ remaining + -> Timeout.Handle + -> IO ByteString + -> IO (IO ByteString) +timeoutBody remainingRef timeoutHandle rbody = do isFirstRef <- I.newIORef True + let checkEmpty = + case remainingRef of + Nothing -> return . S.null + Just ref -> \bs -> if S.null bs + then return True + else do + x <- I.readIORef ref + return $! x <= 0 + return $ do isFirst <- I.readIORef isFirstRef - when isFirst $ + when isFirst $ do -- Timeout handling was paused after receiving the full request -- headers. Now we need to resume it to avoid a slowloris -- attack during request body sending. Timeout.resume timeoutHandle + I.writeIORef isFirstRef False bs <- rbody @@ -157,7 +174,8 @@ -- because the application is not interested in more bytes, or -- because there is no more data available, pause the timeout -- handler again. - when (S.null bs) (Timeout.pause timeoutHandle) + isEmpty <- checkEmpty bs + when isEmpty (Timeout.pause timeoutHandle) return bs @@ -247,3 +265,7 @@ checkCR bs pos = if pos > 0 && 13 == S.index bs p then p else pos -- 13 is CR where !p = pos - 1 + +pauseTimeoutKey :: Vault.Key (IO ()) +pauseTimeoutKey = unsafePerformIO Vault.newKey +{-# NOINLINE pauseTimeoutKey #-} diff --git a/warp.cabal b/warp.cabal --- a/warp.cabal +++ b/warp.cabal @@ -1,5 +1,5 @@ Name: warp -Version: 3.0.9.3 +Version: 3.0.10 Synopsis: A fast, light-weight web server for WAI applications. License: MIT License-file: LICENSE @@ -46,6 +46,7 @@ , wai >= 3.0 && < 3.1 , text , streaming-commons >= 0.1.10 + , vault >= 0.3 if flag(network-bytestring) Build-Depends: network >= 2.2.1.5 && < 2.2.3 , network-bytestring >= 0.1.3 && < 0.1.4 @@ -143,6 +144,7 @@ , text , streaming-commons >= 0.1.10 , async + , vault if flag(use-bytestring-builder) Build-Depends: bytestring < 0.10.2.0 , bytestring-builder