shrub/pkg/hs/urbit-king/lib/Urbit/Vere/Eyre/Serv.hs
2020-06-11 02:02:53 +00:00

357 lines
9.9 KiB
Haskell

{-|
Runs a single HTTP (or HTTPS) server for the eyre driver.
A server is given:
- A port, or a range or ports.
- Opens a socket on one of those ports.
- If this fails, try again repeatedly.
- Once a socket is opened, runs an HTTP server on the specified port.
- Once the server is up, calls a callback with the port that was opened.
- Once we have chosen a port, we commit to that port (ignoring the
original range).
- If the socket ever goes down, keep trying to reopen that port forever.
- When the server is shutdown, make sure the socket is closed.
TODO How to detect socket closed during server run?
-}
{-# OPTIONS_GHC -Wno-deprecations #-}
module Urbit.Vere.Eyre.Serv
( ServApi(..)
, TlsConfig(..)
, MultiTlsConfig(..)
, ReqApi(..)
, ServType(..)
, ServPort(..)
, ServHost(..)
, ServConf(..)
, configCreds
, serv
, fakeServ
)
where
import Urbit.Prelude hiding (Builder)
import Data.Default (def)
import Data.List.NonEmpty (NonEmpty((:|)))
import Network.TLS (Credential, Credentials(..), ServerHooks(..))
import Network.TLS (credentialLoadX509ChainFromMemory)
import RIO.Prelude (decodeUtf8Lenient)
import qualified Control.Monad.STM as STM
import qualified Data.Char as C
import qualified Network.Socket as Net
import qualified Network.Wai as W
import qualified Network.Wai.Handler.Warp as W
import qualified Network.Wai.Handler.WarpTLS as W
import qualified Urbit.Ob as Ob
import qualified Urbit.Vere.Eyre.Wai as E
-- Internal Types --------------------------------------------------------------
data ServApi = ServApi
{ saKil :: STM ()
, saPor :: STM W.Port
}
data TlsConfig = TlsConfig
{ tcPrKey :: ByteString
, tcCerti :: ByteString
, tcChain :: [ByteString]
}
deriving (Show)
newtype MultiTlsConfig = MTC (TVar (Map Ship (TlsConfig, Credential)))
instance Show MultiTlsConfig where
show = const "MultiTlsConfig"
data ReqApi = ReqApi
{ rcReq :: Ship -> Word64 -> E.ReqInfo -> STM ()
, rcKil :: Ship -> Word64 -> STM ()
}
instance Show ReqApi where
show = const "ReqApi"
data ServType
= STHttp Ship ReqApi
| STHttps Ship TlsConfig ReqApi
| STMultiHttp ReqApi
| STMultiHttps MultiTlsConfig ReqApi
deriving (Show)
data ServPort
= SPAnyPort
| SPChoices (NonEmpty W.Port)
deriving (Show)
data ServHost
= SHLocalhost
| SHAnyHostOk
deriving (Show)
data ServConf = ServConf
{ scType :: ServType
, scHost :: ServHost
, scPort :: ServPort
, scRedi :: Maybe W.Port
, scFake :: Bool
}
deriving (Show)
-- Opening Sockets -------------------------------------------------------------
getBindAddr :: String -> W.Port -> IO Net.SockAddr
getBindAddr hos por =
Net.getAddrInfo Nothing (Just hos) (Just (show por)) >>= \case
[] -> error "this should never happen."
x : _ -> pure (Net.addrAddress x)
bindListenPort :: String -> W.Port -> Net.Socket -> IO Net.PortNumber
bindListenPort hos por sok = do
Net.bind sok =<< getBindAddr hos por
Net.listen sok 1
Net.socketPort sok
tcpSocket :: IO (Either IOError Net.Socket)
tcpSocket =
tryIOError (Net.socket Net.AF_INET Net.Stream Net.defaultProtocol)
tryOpen :: String -> W.Port -> IO (Either IOError (W.Port, Net.Socket))
tryOpen hos por =
tcpSocket >>= \case
Left exn -> pure (Left exn)
Right sok -> tryIOError (bindListenPort hos por sok) >>= \case
Left exn -> Net.close sok $> Left exn
Right por -> pure (Right (fromIntegral por, sok))
openFreePort :: String -> IO (Either IOError (W.Port, Net.Socket))
openFreePort hos = do
tcpSocket >>= \case
Left exn -> pure (Left exn)
Right sok -> tryIOError (doBind sok) >>= \case
Left exn -> Net.close sok $> Left exn
Right ps -> pure (Right ps)
where
doBind sok = do
adr <- Net.inet_addr hos
Net.bind sok (Net.SockAddrInet Net.defaultPort adr)
Net.listen sok 1
port <- Net.socketPort sok
pure (fromIntegral port, sok)
retry :: HasLogFunc e => RIO e (Either IOError a) -> RIO e a
retry act = act >>= \case
Right res -> pure res
Left exn -> do
logDbg ctx ("Failed to open ports. Waiting 5s, then trying again.", exn)
threadDelay 5_000_000
retry act
where
ctx = ["EYRE", "SERV", "retry"]
tryOpenChoices
:: HasLogFunc e
=> String
-> NonEmpty W.Port
-> RIO e (Either IOError (W.Port, Net.Socket))
tryOpenChoices hos = go
where
go (p :| ps) = do
logDebug (displayShow ("EYRE", "Trying to open port.", p))
io (tryOpen hos p) >>= \case
Left err -> do
logError (displayShow ("EYRE", "Failed to open port.", p))
case ps of
[] -> pure (Left err)
q : qs -> go (q :| qs)
Right (p, s) -> do
pure (Right (p, s))
tryOpenAny
:: HasLogFunc e => String -> RIO e (Either IOError (W.Port, Net.Socket))
tryOpenAny hos = do
let ctx = ["EYRE", "SERV", "tryOpenAny"]
logDbg ctx "Asking the OS for any free port."
io (openFreePort hos) >>= \case
Left exn -> pure (Left exn)
Right (p, s) -> do
pure (Right (p, s))
logDbg :: (HasLogFunc e, Show a) => [Text] -> a -> RIO e ()
logDbg ctx msg = logDebug (prefix <> suffix)
where
prefix = display (concat $ fmap (<> ": ") ctx)
suffix = displayShow msg
forceOpenSocket
:: forall e
. HasLogFunc e
=> ServHost
-> ServPort
-> RAcquire e (W.Port, Net.Socket)
forceOpenSocket hos por = mkRAcquire opn kil
where
kil = io . Net.close . snd
opn = do
let ctx = ["EYRE", "SERV", "forceOpenSocket"]
logDbg ctx (hos, por)
(p, s) <- retry $ case por of
SPAnyPort -> tryOpenAny bind
SPChoices ps -> tryOpenChoices bind ps
logDbg ctx ("Opened port.", p)
pure (p, s)
bind = case hos of
SHLocalhost -> "127.0.0.1"
SHAnyHostOk -> "0.0.0.0"
-- Starting WAI ----------------------------------------------------------------
hostShip :: Maybe ByteString -> IO Ship
hostShip Nothing = error "Request must contain HOST header."
hostShip (Just bs) = byteShip (hedLabel bs) & \case
Left err -> error ("Bad host prefix. Must be a ship name: " <> unpack err)
Right sp -> pure sp
where
byteShip = fmap (fromIntegral . Ob.fromPatp) . bytePatp
bytePatp = Ob.parsePatp . decodeUtf8Lenient
hedLabel = fst . break (== fromIntegral (C.ord '.'))
onSniHdr
:: HasLogFunc e => e -> MultiTlsConfig -> Maybe String -> IO Credentials
onSniHdr env (MTC mtls) mHos = do
tabl <- atomically (readTVar mtls)
runRIO env $ logDbg ctx (tabl, mHos)
ship <- hostShip (encodeUtf8 . pack <$> mHos)
runRIO env $ logDbg ctx ship
tcfg <- lookup ship tabl & maybe (notRunning ship) (pure . snd)
runRIO env $ logDbg ctx tcfg
pure (Credentials [tcfg])
where
notRunning ship = error ("Ship not running: ~" <> show ship)
ctx = ["EYRE", "HTTPS", "SNI"]
startServer
:: HasLogFunc e
=> ServType
-> ServHost
-> W.Port
-> Net.Socket
-> Maybe W.Port
-> TVar E.LiveReqs
-> RIO e ()
startServer typ hos por sok red vLive = do
envir <- ask
let host = case hos of
SHLocalhost -> "127.0.0.1"
SHAnyHostOk -> "*"
let opts =
W.defaultSettings
& W.setHost host
& W.setPort (fromIntegral por)
& W.setTimeout (5 * 60)
let runAppl who = E.app envir who vLive
reqShip = hostShip . W.requestHeaderHost
case typ of
STHttp who api -> do
let app = runAppl who (rcReq api who) (rcKil api who)
io (W.runSettingsSocket opts sok app)
STHttps who TlsConfig {..} api -> do
let tls = W.tlsSettingsChainMemory tcCerti tcChain tcPrKey
let app = runAppl who (rcReq api who) (rcKil api who)
io (W.runTLSSocket tls opts sok app)
STMultiHttp api -> do
let app req resp = do
who <- reqShip req
runAppl who (rcReq api who) (rcKil api who) req resp
io (W.runSettingsSocket opts sok app)
STMultiHttps mtls api -> do
TlsConfig {..} <- atomically (getFirstTlsConfig mtls)
let sni = def { onServerNameIndication = onSniHdr envir mtls }
let tlsSing = (W.tlsSettingsChainMemory tcCerti tcChain tcPrKey)
let tlsMany = tlsSing { W.tlsServerHooks = sni }
let ctx = ["EYRE", "HTTPS", "REQ"]
let
app = \req resp -> do
runRIO envir $ logDbg ctx "Got request"
who <- reqShip req
runRIO envir $ logDbg ctx ("Parsed HOST", who)
runAppl who (rcReq api who) (rcKil api who) req resp
io (W.runTLSSocket tlsMany opts sok app)
--------------------------------------------------------------------------------
configCreds :: TlsConfig -> Either Text Credential
configCreds TlsConfig {..} =
credentialLoadX509ChainFromMemory tcCerti tcChain tcPrKey & \case
Left str -> Left (pack str)
Right rs -> Right rs
fakeServ :: HasLogFunc e => ServConf -> RIO e ServApi
fakeServ conf = do
let por = fakePort (scPort conf)
logDebug (displayShow ("EYRE", "SERV", "Running Fake Server", por))
pure $ ServApi
{ saKil = pure ()
, saPor = pure por
}
where
fakePort :: ServPort -> W.Port
fakePort SPAnyPort = 55555
fakePort (SPChoices (x :| _)) = x
getFirstTlsConfig :: MultiTlsConfig -> STM TlsConfig
getFirstTlsConfig (MTC var) = do
map <- readTVar var
case toList map of
[] -> STM.retry
x:_ -> pure (fst x)
realServ :: HasLogFunc e => TVar E.LiveReqs -> ServConf -> RIO e ServApi
realServ vLive conf@ServConf {..} = do
logDebug (displayShow ("EYRE", "SERV", "Running Real Server"))
kil <- newEmptyTMVarIO
por <- newEmptyTMVarIO
tid <- async (runServ por)
_ <- async (atomically (takeTMVar kil) >> cancel tid)
pure $ ServApi
{ saKil = void (tryPutTMVar kil ())
, saPor = readTMVar por
}
where
runServ vPort = do
logDebug (displayShow ("EYRE", "SERV", "runServ"))
rwith (forceOpenSocket scHost scPort) $ \(por, sok) -> do
atomically (putTMVar vPort por)
startServer scType scHost por sok scRedi vLive
serv :: HasLogFunc e => TVar E.LiveReqs -> ServConf -> RIO e ServApi
serv vLive conf = do
if scFake conf
then fakeServ conf
else realServ vLive conf