happstack-server-tls-7.2.1: src/Happstack/Server/Internal/TLS.hs
{-# LANGUAGE CPP, ScopedTypeVariables #-}
{- | core functions and types for HTTPS support
-}
module Happstack.Server.Internal.TLS where
import Control.Concurrent (forkIO, killThread, myThreadId)
import Control.Exception.Extensible as E
import Control.Monad (forever, when)
import Data.Time (UTCTime)
import GHC.IO.Exception (IOErrorType(..))
import Happstack.Server.Internal.Listen (listenOn)
import Happstack.Server.Internal.Handler (request)
import Happstack.Server.Internal.Socket (acceptLite)
import Happstack.Server.Internal.TimeoutManager (cancel, initialize, register)
import Happstack.Server.Internal.TimeoutSocketTLS as TSS
import Happstack.Server.Internal.Types (Request, Response)
import Network.Socket (HostName, PortNumber, Socket, close, socketPort)
import Prelude hiding (catch)
import OpenSSL (withOpenSSL)
import OpenSSL.Session (SSL, SSLContext)
import qualified OpenSSL.Session as SSL
import Happstack.Server.Types (LogAccess, logMAccess)
import System.IO.Error (ioeGetErrorType, isFullError, isDoesNotExistError)
import System.Log.Logger (Priority(..), logM)
#ifndef mingw32_HOST_OS
import System.Posix.Signals (Handler(Ignore), installHandler, openEndedPipe)
#endif
-- | wrapper around 'logM' for this module
log':: Priority -> String -> IO ()
log' = logM "Happstack.Server.Internal.TLS"
-- | configuration for using https:\/\/
data TLSConf = TLSConf {
tlsPort :: Int -- port (usually 443)
, tlsCert :: FilePath -- path to SSL certificate
, tlsKey :: FilePath -- path to SSL private key
, tlsCA :: Maybe FilePath -- PEM encoded list of CA certificates
, tlsTimeout :: Int -- kill connect of timeout (in seconds)
, tlsLogAccess :: Maybe (LogAccess UTCTime) -- see 'logMAccess'
, tlsValidator :: Maybe (Response -> IO Response) -- ^ a function to validate the output on-the-fly
}
-- | a partially complete 'TLSConf' . You must sete 'tlsCert' and 'tlsKey' at a mininum.
nullTLSConf :: TLSConf
nullTLSConf =
TLSConf { tlsPort = 443
, tlsCert = ""
, tlsKey = ""
, tlsCA = Nothing
, tlsTimeout = 30
, tlsLogAccess = Just logMAccess
, tlsValidator = Nothing
}
-- | record that holds the 'Socket' and 'SSLContext' needed to start
-- the https:\/\/ event loop. Used with 'simpleHTTPWithSocket''
--
-- see also: 'httpOnSocket'
data HTTPS = HTTPS
{ httpsSocket :: Socket
, sslContext :: SSLContext
}
-- | generate the 'HTTPS' record needed to start the https:\/\/ event loop
--
httpsOnSocket :: FilePath -- ^ path to ssl certificate
-> FilePath -- ^ path to ssl private key
-> Maybe FilePath -- ^ path to PEM encoded list of CA certificates
-> Socket -- ^ listening socket (on which listen() has been called, but not accept())
-> IO HTTPS
httpsOnSocket cert key mca socket =
do ctx <- SSL.context
SSL.contextSetPrivateKeyFile ctx key
SSL.contextSetCertificateFile ctx cert
case mca of
Nothing -> return ()
(Just ca) -> SSL.contextSetCAFile ctx ca
SSL.contextSetDefaultCiphers ctx
certOk <- SSL.contextCheckPrivateKey ctx
when (not certOk) $ error $ "OpenTLS certificate and key do not match."
return (HTTPS socket ctx)
-- | accept a TLS connection
acceptTLS :: Socket -- ^ the socket returned from 'acceptLite'
-> SSLContext
-> IO SSL
acceptTLS sck ctx =
handle (\ (e :: SomeException) -> close sck >> throwIO e) $ do
ssl <- SSL.connection ctx sck
SSL.accept ssl
return ssl
-- | https:// 'Request'/'Response' loop
--
-- This function initializes SSL, and starts accepting and handling
-- 'Request's and sending 'Respone's.
--
-- Each 'Request' is processed in a separate thread.
listenTLS :: TLSConf -- ^ tls configuration
-> (Request -> IO Response) -- ^ request handler
-> IO ()
listenTLS tlsConf hand =
do withOpenSSL $ return ()
tlsSocket <- listenOn (tlsPort tlsConf)
https <- httpsOnSocket (tlsCert tlsConf) (tlsKey tlsConf) (tlsCA tlsConf) tlsSocket
listenTLS' (tlsTimeout tlsConf) (tlsLogAccess tlsConf) https hand
-- | low-level https:// 'Request'/'Response' loop
--
-- This is the low-level loop that reads 'Request's and sends
-- 'Respone's. It assumes that SSL has already been initialized and
-- that socket is listening.
--
-- Each 'Request' is processed in a separate thread.
--
-- see also: 'listenTLS'
listenTLS' :: Int -> Maybe (LogAccess UTCTime) -> HTTPS -> (Request -> IO Response) -> IO ()
listenTLS' timeout mlog https@(HTTPS lsocket _) handler = do
#ifndef mingw32_HOST_OS
installHandler openEndedPipe Ignore Nothing
#endif
tm <- initialize (timeout * (10^(6 :: Int)))
do let work :: (Socket, SSL, HostName, PortNumber) -> IO ()
work (socket, ssl, hn, p) =
do -- add this thread to the timeout table
tid <- myThreadId
thandle <- register tm $ do shutdownClose socket ssl
killThread tid
-- handle the request
let timeoutIO = TSS.timeoutSocketIO thandle socket ssl
request timeoutIO mlog (hn, fromIntegral p) handler
`E.catches` [ Handler ignoreConnectionAbruptlyTerminated
, Handler ehs
]
-- remove thread from timeout table
cancel thandle
-- close connection
shutdownClose socket ssl
loop :: IO ()
loop = forever $ do -- do a normal accept
(sck, peer, port) <- acceptLite (httpsSocket https)
forkIO $ do -- do the TLS accept/handshake
ssl <- acceptTLS sck (sslContext https)
work (sck, ssl, peer, port)
`catch` (\(e :: SomeException) -> do
shutdownClose sck ssl
throwIO e)
return ()
pe e = log' ERROR ("ERROR in https accept thread: " ++ show e)
infi = loop `catchSome` pe >> infi
-- sockName <- getSocketName lsocket
sockPort <- socketPort lsocket
log' NOTICE ("Listening for https:// on port " ++ show sockPort)
(infi `catch` (\e -> do log' ERROR ("https:// terminated by " ++ show (e :: SomeException))
throwIO e))
`finally` (close lsocket)
where
shutdownClose :: Socket -> SSL -> IO ()
shutdownClose socket ssl =
do SSL.shutdown ssl SSL.Unidirectional `E.catch` ignoreException
close socket `E.catch` ignoreException
-- exception handlers
ignoreConnectionAbruptlyTerminated :: SSL.ConnectionAbruptlyTerminated -> IO ()
ignoreConnectionAbruptlyTerminated _ = return ()
ignoreSSLException :: SSL.SomeSSLException -> IO ()
ignoreSSLException _ = return ()
ignoreException :: SomeException -> IO ()
ignoreException _ = return ()
ehs :: SomeException -> IO ()
ehs x = when ((fromException x) /= Just ThreadKilled) $ log' ERROR ("HTTPS request failed with: " ++ show x)
catchSome op h =
op `E.catches` [ Handler $ ignoreSSLException
, Handler $ \(e :: ArithException) -> h (toException e)
, Handler $ \(e :: ArrayException) -> h (toException e)
, Handler $ \(e :: IOException) ->
if isFullError e || isDoesNotExistError e || isResourceVanishedError e
then return () -- h (toException e) -- we could log the exception, but there could be thousands of them
else log' ERROR ("HTTPS accept loop ignoring " ++ show e)
]
isResourceVanishedError :: IOException -> Bool
isResourceVanishedError = isResourceVanishedType . ioeGetErrorType
isResourceVanishedType :: IOErrorType -> Bool
isResourceVanishedType ResourceVanished = True
isResourceVanishedType _ = False