aa1ad0b7ca
Clean build under ghc 8.8.3, which seems to do better at finding cases where two imports both provide the same symbol, and warns about one of them. This commit was sponsored by Ilya Shlyakhter on Patreon.
392 lines
11 KiB
Haskell
392 lines
11 KiB
Haskell
{- P2P protocol, IO implementation
|
|
-
|
|
- Copyright 2016-2018 Joey Hess <id@joeyh.name>
|
|
-
|
|
- Licensed under the GNU AGPL version 3 or higher.
|
|
-}
|
|
|
|
{-# LANGUAGE RankNTypes, FlexibleContexts, CPP #-}
|
|
|
|
module P2P.IO
|
|
( RunProto
|
|
, RunState(..)
|
|
, mkRunState
|
|
, P2PConnection(..)
|
|
, ConnIdent(..)
|
|
, ClosableConnection(..)
|
|
, stdioP2PConnection
|
|
, connectPeer
|
|
, closeConnection
|
|
, serveUnixSocket
|
|
, setupHandle
|
|
, ProtoFailure(..)
|
|
, describeProtoFailure
|
|
, runNetProto
|
|
, runNet
|
|
) where
|
|
|
|
import Common
|
|
import P2P.Protocol
|
|
import P2P.Address
|
|
import Git
|
|
import Git.Command
|
|
import Utility.AuthToken
|
|
import Utility.SimpleProtocol
|
|
import Utility.Metered
|
|
import Utility.Tor
|
|
import Utility.FileMode
|
|
import Types.UUID
|
|
import Annex.ChangedRefs
|
|
|
|
import Control.Monad.Free
|
|
import Control.Monad.IO.Class
|
|
import System.IO.Error
|
|
import Network.Socket
|
|
import Control.Concurrent
|
|
import Control.Concurrent.Async
|
|
import Control.Concurrent.STM
|
|
import qualified Data.ByteString as B
|
|
import qualified Data.ByteString.Lazy as L
|
|
import System.Log.Logger (debugM)
|
|
import qualified Network.Socket as S
|
|
|
|
-- Type of interpreters of the Proto free monad.
|
|
type RunProto m = forall a. Proto a -> m (Either ProtoFailure a)
|
|
|
|
data ProtoFailure
|
|
= ProtoFailureMessage String
|
|
| ProtoFailureException SomeException
|
|
| ProtoFailureIOError IOError
|
|
|
|
describeProtoFailure :: ProtoFailure -> String
|
|
describeProtoFailure (ProtoFailureMessage s) = s
|
|
describeProtoFailure (ProtoFailureException e) = show e
|
|
describeProtoFailure (ProtoFailureIOError e) = show e
|
|
|
|
data RunState
|
|
= Serving UUID (Maybe ChangedRefsHandle) (TVar ProtocolVersion)
|
|
| Client (TVar ProtocolVersion)
|
|
|
|
mkRunState :: (TVar ProtocolVersion -> RunState) -> IO RunState
|
|
mkRunState mk = do
|
|
tvar <- newTVarIO defaultProtocolVersion
|
|
return (mk tvar)
|
|
|
|
data P2PConnection = P2PConnection
|
|
{ connRepo :: Repo
|
|
, connCheckAuth :: (AuthToken -> Bool)
|
|
, connIhdl :: Handle
|
|
, connOhdl :: Handle
|
|
, connIdent :: ConnIdent
|
|
}
|
|
|
|
-- Identifier for a connection, only used for debugging.
|
|
newtype ConnIdent = ConnIdent (Maybe String)
|
|
|
|
data ClosableConnection conn
|
|
= OpenConnection conn
|
|
| ClosedConnection
|
|
|
|
-- P2PConnection using stdio.
|
|
stdioP2PConnection :: Git.Repo -> P2PConnection
|
|
stdioP2PConnection g = P2PConnection
|
|
{ connRepo = g
|
|
, connCheckAuth = const False
|
|
, connIhdl = stdin
|
|
, connOhdl = stdout
|
|
, connIdent = ConnIdent Nothing
|
|
}
|
|
|
|
-- Opens a connection to a peer. Does not authenticate with it.
|
|
connectPeer :: Git.Repo -> P2PAddress -> IO P2PConnection
|
|
connectPeer g (TorAnnex onionaddress onionport) = do
|
|
h <- setupHandle =<< connectHiddenService onionaddress onionport
|
|
return $ P2PConnection
|
|
{ connRepo = g
|
|
, connCheckAuth = const False
|
|
, connIhdl = h
|
|
, connOhdl = h
|
|
, connIdent = ConnIdent Nothing
|
|
}
|
|
|
|
closeConnection :: P2PConnection -> IO ()
|
|
closeConnection conn = do
|
|
hClose (connIhdl conn)
|
|
hClose (connOhdl conn)
|
|
|
|
-- Serves the protocol on a unix socket.
|
|
--
|
|
-- The callback is run to serve a connection, and is responsible for
|
|
-- closing the Handle when done.
|
|
--
|
|
-- Note that while the callback is running, other connections won't be
|
|
-- processed, so longterm work should be run in a separate thread by
|
|
-- the callback.
|
|
serveUnixSocket :: FilePath -> (Handle -> IO ()) -> IO ()
|
|
serveUnixSocket unixsocket serveconn = do
|
|
nukeFile unixsocket
|
|
soc <- S.socket S.AF_UNIX S.Stream S.defaultProtocol
|
|
S.bind soc (S.SockAddrUnix unixsocket)
|
|
-- Allow everyone to read and write to the socket,
|
|
-- so a daemon like tor, that is probably running as a different
|
|
-- de sock $ addModes
|
|
-- user, can access it.
|
|
--
|
|
-- Connections have to authenticate to do anything,
|
|
-- so it's fine that other local users can connect to the
|
|
-- socket.
|
|
modifyFileMode unixsocket $ addModes
|
|
[groupReadMode, groupWriteMode, otherReadMode, otherWriteMode]
|
|
S.listen soc 2
|
|
forever $ do
|
|
(conn, _) <- S.accept soc
|
|
setupHandle conn >>= serveconn
|
|
|
|
setupHandle :: Socket -> IO Handle
|
|
setupHandle s = do
|
|
h <- socketToHandle s ReadWriteMode
|
|
hSetBuffering h LineBuffering
|
|
hSetBinaryMode h False
|
|
return h
|
|
|
|
-- Purposefully incomplete interpreter of Proto.
|
|
--
|
|
-- This only runs Net actions. No Local actions will be run
|
|
-- (those need the Annex monad) -- if the interpreter reaches any,
|
|
-- it returns Nothing.
|
|
runNetProto :: RunState -> P2PConnection -> Proto a -> IO (Either ProtoFailure a)
|
|
runNetProto runst conn = go
|
|
where
|
|
go :: RunProto IO
|
|
go (Pure v) = return (Right v)
|
|
go (Free (Net n)) = runNet runst conn go n
|
|
go (Free (Local _)) = return $ Left $
|
|
ProtoFailureMessage "unexpected annex operation attempted"
|
|
|
|
-- Interpreter of the Net part of Proto.
|
|
--
|
|
-- An interpreter of Proto has to be provided, to handle the rest of Proto
|
|
-- actions.
|
|
runNet :: (MonadIO m, MonadMask m) => RunState -> P2PConnection -> RunProto m -> NetF (Proto a) -> m (Either ProtoFailure a)
|
|
runNet runst conn runner f = case f of
|
|
SendMessage m next -> do
|
|
v <- liftIO $ tryNonAsync $ do
|
|
let l = unwords (formatMessage m)
|
|
debugMessage conn "P2P >" m
|
|
hPutStrLn (connOhdl conn) l
|
|
hFlush (connOhdl conn)
|
|
case v of
|
|
Left e -> return $ Left $ ProtoFailureException e
|
|
Right () -> runner next
|
|
ReceiveMessage next -> do
|
|
v <- liftIO $ tryIOError $ getProtocolLine (connIhdl conn)
|
|
case v of
|
|
Left e -> return $ Left $ ProtoFailureIOError e
|
|
Right Nothing -> return $ Left $
|
|
ProtoFailureMessage "protocol error"
|
|
Right (Just l) -> case parseMessage l of
|
|
Just m -> do
|
|
liftIO $ debugMessage conn "P2P <" m
|
|
runner (next (Just m))
|
|
Nothing -> runner (next Nothing)
|
|
SendBytes len b p next -> do
|
|
v <- liftIO $ tryNonAsync $ do
|
|
ok <- sendExactly len b (connOhdl conn) p
|
|
hFlush (connOhdl conn)
|
|
return ok
|
|
case v of
|
|
Right True -> runner next
|
|
Right False -> return $ Left $
|
|
ProtoFailureMessage "short data write"
|
|
Left e -> return $ Left $ ProtoFailureException e
|
|
ReceiveBytes len p next -> do
|
|
v <- liftIO $ tryNonAsync $ receiveExactly len (connIhdl conn) p
|
|
case v of
|
|
Left e -> return $ Left $ ProtoFailureException e
|
|
Right b -> runner (next b)
|
|
CheckAuthToken _u t next -> do
|
|
let authed = connCheckAuth conn t
|
|
runner (next authed)
|
|
Relay hin hout next -> do
|
|
v <- liftIO $ runRelay runnerio hin hout
|
|
case v of
|
|
Left e -> return $ Left e
|
|
Right exitcode -> runner (next exitcode)
|
|
RelayService service next -> do
|
|
v <- liftIO $ runRelayService conn runnerio service
|
|
case v of
|
|
Left e -> return $ Left e
|
|
Right () -> runner next
|
|
SetProtocolVersion v next -> do
|
|
liftIO $ atomically $ writeTVar versiontvar v
|
|
runner next
|
|
GetProtocolVersion next ->
|
|
liftIO (readTVarIO versiontvar) >>= runner . next
|
|
where
|
|
-- This is only used for running Net actions when relaying,
|
|
-- so it's ok to use runNetProto, despite it not supporting
|
|
-- all Proto actions.
|
|
runnerio = runNetProto runst conn
|
|
versiontvar = case runst of
|
|
Serving _ _ tv -> tv
|
|
Client tv -> tv
|
|
|
|
debugMessage :: P2PConnection -> String -> Message -> IO ()
|
|
debugMessage conn prefix m = do
|
|
tid <- myThreadId
|
|
debugM "p2p" $ concat $ catMaybes $
|
|
[ (\ident -> "[" ++ ident ++ "] ") <$> mident
|
|
, Just $ "[" ++ show tid ++ "] "
|
|
, Just $ prefix ++ " " ++ unwords (formatMessage safem)
|
|
]
|
|
where
|
|
safem = case m of
|
|
AUTH u _ -> AUTH u nullAuthToken
|
|
_ -> m
|
|
ConnIdent mident = connIdent conn
|
|
|
|
-- Send exactly the specified number of bytes or returns False.
|
|
--
|
|
-- The ByteString can be larger or smaller than the specified length.
|
|
-- For example, it can be lazily streaming from a file that gets
|
|
-- appended to, or truncated.
|
|
--
|
|
-- Must avoid sending too many bytes as it would confuse the other end.
|
|
-- This is easily dealt with by truncating it.
|
|
--
|
|
-- If too few bytes are sent, the only option is to give up on this
|
|
-- connection. False is returned to indicate this problem.
|
|
sendExactly :: Len -> L.ByteString -> Handle -> MeterUpdate -> IO Bool
|
|
sendExactly (Len n) b h p = do
|
|
sent <- meteredWrite' p h (L.take (fromIntegral n) b)
|
|
return (fromBytesProcessed sent == n)
|
|
|
|
receiveExactly :: Len -> Handle -> MeterUpdate -> IO L.ByteString
|
|
receiveExactly (Len n) h p = hGetMetered h (Just n) p
|
|
|
|
runRelay :: RunProto IO -> RelayHandle -> RelayHandle -> IO (Either ProtoFailure ExitCode)
|
|
runRelay runner (RelayHandle hout) (RelayHandle hin) =
|
|
bracket setup cleanup go
|
|
`catchNonAsync` (return . Left . ProtoFailureException)
|
|
where
|
|
setup = do
|
|
v <- newEmptyMVar
|
|
t1 <- async $ relayFeeder runner v hin
|
|
t2 <- async $ relayReader v hout
|
|
return (v, t1, t2)
|
|
|
|
cleanup (_, t1, t2) = do
|
|
hClose hin
|
|
hClose hout
|
|
cancel t1
|
|
cancel t2
|
|
|
|
go (v, _, _) = relayHelper runner v
|
|
|
|
runRelayService :: P2PConnection -> RunProto IO -> Service -> IO (Either ProtoFailure ())
|
|
runRelayService conn runner service =
|
|
withCreateProcess serviceproc' go
|
|
`catchNonAsync` (return . Left . ProtoFailureException)
|
|
where
|
|
cmd = case service of
|
|
UploadPack -> "upload-pack"
|
|
ReceivePack -> "receive-pack"
|
|
|
|
serviceproc = gitCreateProcess
|
|
[ Param cmd
|
|
, File (fromRawFilePath (repoPath (connRepo conn)))
|
|
] (connRepo conn)
|
|
serviceproc' = serviceproc
|
|
{ std_out = CreatePipe
|
|
, std_in = CreatePipe
|
|
}
|
|
|
|
go (Just hin) (Just hout) _ pid = do
|
|
v <- newEmptyMVar
|
|
r <- withAsync (relayFeeder runner v hin) $ \_ ->
|
|
withAsync (relayReader v hout) $ \_ ->
|
|
withAsync (waitexit v pid) $ \_ -> do
|
|
r <- runrelay v
|
|
hClose hin
|
|
hClose hout
|
|
return r
|
|
void $ waitForProcess pid
|
|
return r
|
|
go _ _ _ _ = error "internal"
|
|
|
|
runrelay v = relayHelper runner v >>= \case
|
|
Left e -> return $ Left e
|
|
Right exitcode -> runner $
|
|
net $ relayToPeer (RelayDone exitcode)
|
|
|
|
waitexit v pid = putMVar v . RelayDone =<< waitForProcess pid
|
|
|
|
-- Processes RelayData as it is put into the MVar.
|
|
relayHelper :: RunProto IO -> MVar RelayData -> IO (Either ProtoFailure ExitCode)
|
|
relayHelper runner v = loop
|
|
where
|
|
loop = do
|
|
d <- takeMVar v
|
|
case d of
|
|
RelayToPeer b -> do
|
|
r <- runner $ net $ relayToPeer (RelayToPeer b)
|
|
case r of
|
|
Left e -> return (Left e)
|
|
Right () -> loop
|
|
RelayDone exitcode -> do
|
|
_ <- runner $ net $ relayToPeer (RelayDone exitcode)
|
|
return (Right exitcode)
|
|
RelayFromPeer _ -> loop -- not handled here
|
|
|
|
-- Takes input from the peer, and sends it to the relay process's stdin.
|
|
-- Repeats until the peer tells it it's done or hangs up.
|
|
relayFeeder :: RunProto IO -> MVar RelayData -> Handle -> IO ()
|
|
relayFeeder runner v hin = loop
|
|
where
|
|
loop = do
|
|
mrd <- runner $ net relayFromPeer
|
|
case mrd of
|
|
Left _e ->
|
|
putMVar v (RelayDone (ExitFailure 1))
|
|
Right (RelayDone exitcode) ->
|
|
putMVar v (RelayDone exitcode)
|
|
Right (RelayFromPeer b) -> do
|
|
L.hPut hin b
|
|
hFlush hin
|
|
loop
|
|
Right (RelayToPeer _) -> loop -- not handled here
|
|
|
|
-- Reads input from the Handle and puts it into the MVar for relaying to
|
|
-- the peer. Continues until EOF on the Handle.
|
|
relayReader :: MVar RelayData -> Handle -> IO ()
|
|
relayReader v hout = loop
|
|
where
|
|
loop = do
|
|
bs <- getsome []
|
|
case bs of
|
|
[] -> return ()
|
|
_ -> do
|
|
putMVar v $ RelayToPeer (L.fromChunks bs)
|
|
loop
|
|
|
|
-- Wait for the first available chunk. Then, without blocking,
|
|
-- try to get more chunks, in case a stream of chunks is being
|
|
-- written in close succession.
|
|
--
|
|
-- On Windows, hGetNonBlocking is broken, so avoid using it there.
|
|
getsome [] = do
|
|
b <- B.hGetSome hout chunk
|
|
if B.null b
|
|
then return []
|
|
#ifndef mingw32_HOST_OS
|
|
else getsome [b]
|
|
#else
|
|
else return [b]
|
|
#endif
|
|
getsome bs = do
|
|
b <- B.hGetNonBlocking hout chunk
|
|
if B.null b
|
|
then return (reverse bs)
|
|
else getsome (b:bs)
|
|
|
|
chunk = 65536
|