remotedaemon: git change detection over tor hidden service

4 files changed, 93 insertions, 35 deletions

diff --git a/RemoteDaemon/Common.hs b/RemoteDaemon/Common.hs
index 982a84b43..711771f97 100644
--- a/RemoteDaemon/Common.hs
+++ b/RemoteDaemon/Common.hs
@@ -1,6 +1,6 @@
 {- git-remote-daemon utilities
  -
- - Copyright 2014 Joey Hess <id@joeyh.name>
+ - Copyright 2014-2016 Joey Hess <id@joeyh.name>
  -
  - Licensed under the GNU GPL version 3 or higher.
  -}
@@ -9,6 +9,8 @@ module RemoteDaemon.Common
 	( liftAnnex
 	, inLocalRepo
 	, checkNewShas
+	, ConnectionStatus(..)
+	, robustConnection
 	) where
 
 import qualified Annex
@@ -16,6 +18,7 @@ import Annex.Common
 import RemoteDaemon.Types
 import qualified Git
 import Annex.CatFile
+import Utility.ThreadScheduler
 
 import Control.Concurrent
 
@@ -40,3 +43,22 @@ checkNewShas transporthandle = check
 	check [] = return True
 	check (r:rs) = maybe (check rs) (const $ return False)
 		=<< liftAnnex transporthandle (catObjectDetails r)
+
+data ConnectionStatus = ConnectionStopping | ConnectionClosed
+
+{- Make connection robust, retrying on error, with exponential backoff. -}
+robustConnection :: Int -> IO ConnectionStatus -> IO ()
+robustConnection backoff a = 
+	caught =<< a `catchNonAsync` (const $ return ConnectionClosed)
+  where
+	caught ConnectionStopping = return ()
+	caught ConnectionClosed = do
+		threadDelaySeconds (Seconds backoff)
+		robustConnection increasedbackoff a
+
+	increasedbackoff
+		| b2 > maxbackoff = maxbackoff
+		| otherwise = b2
+	  where
+		b2 = backoff * 2
+		maxbackoff = 3600 -- one hour
diff --git a/RemoteDaemon/Transport.hs b/RemoteDaemon/Transport.hs
index 6605012de..053973424 100644
--- a/RemoteDaemon/Transport.hs
+++ b/RemoteDaemon/Transport.hs
@@ -12,6 +12,7 @@ import qualified RemoteDaemon.Transport.Ssh
 import qualified RemoteDaemon.Transport.GCrypt
 import qualified RemoteDaemon.Transport.Tor
 import qualified Git.GCrypt
+import P2P.Address (torAnnexScheme)
 
 import qualified Data.Map as M
 
@@ -22,6 +23,7 @@ remoteTransports :: M.Map TransportScheme Transport
 remoteTransports = M.fromList
 	[ ("ssh:", RemoteDaemon.Transport.Ssh.transport)
 	, (Git.GCrypt.urlScheme, RemoteDaemon.Transport.GCrypt.transport)
+	, (torAnnexScheme, RemoteDaemon.Transport.Tor.transport)
 	]
 
 remoteServers :: [TransportHandle -> IO ()]
diff --git a/RemoteDaemon/Transport/Ssh.hs b/RemoteDaemon/Transport/Ssh.hs
index 59502f8d3..6f8e8323e 100644
--- a/RemoteDaemon/Transport/Ssh.hs
+++ b/RemoteDaemon/Transport/Ssh.hs
@@ -16,7 +16,6 @@ import qualified RemoteDaemon.Transport.Ssh.Types as SshRemote
 import Utility.SimpleProtocol
 import qualified Git
 import Git.Command
-import Utility.ThreadScheduler
 import Annex.ChangedRefs
 
 import Control.Concurrent.STM
@@ -38,7 +37,7 @@ transportUsingCmd cmd params rr@(RemoteRepo r gc) url h@(TransportHandle (LocalR
 
 transportUsingCmd' :: FilePath -> [CommandParam] -> Transport
 transportUsingCmd' cmd params (RemoteRepo r _) url transporthandle ichan ochan =
-	robustly 1 $ do
+	robustConnection 1 $ do
 		(Just toh, Just fromh, Just errh, pid) <-
 			createProcess (proc cmd (toCommand params))
 			{ std_in = CreatePipe
@@ -79,13 +78,13 @@ transportUsingCmd' cmd params (RemoteRepo r _) url transporthandle ichan ochan =
 					fetch
 				handlestdout fromh
 			-- avoid reconnect on protocol error
-			Nothing -> return Stopping
+			Nothing -> return ConnectionStopping
 	
 	handlecontrol = do
 		msg <- atomically $ readTChan ichan
 		case msg of
-			STOP -> return Stopping
-			LOSTNET -> return Stopping
+			STOP -> return ConnectionStopping
+			LOSTNET -> return ConnectionStopping
 			_ -> handlecontrol
 
 	-- Old versions of git-annex-shell that do not support
@@ -103,23 +102,5 @@ transportUsingCmd' cmd params (RemoteRepo r _) url transporthandle ichan ochan =
 					, "needs its git-annex upgraded"
 					, "to 5.20140405 or newer"
 					]
-				return Stopping
+				return ConnectionStopping
 			else handlestderr errh
-
-data Status = Stopping | ConnectionClosed
-
-{- Make connection robustly, with exponential backoff on failure. -}
-robustly :: Int -> IO Status -> IO ()
-robustly backoff a = caught =<< catchDefaultIO ConnectionClosed a
-  where
-	caught Stopping = return ()
-	caught ConnectionClosed = do
-		threadDelaySeconds (Seconds backoff)
-		robustly increasedbackoff a
-
-	increasedbackoff
-		| b2 > maxbackoff = maxbackoff
-		| otherwise = b2
-	  where
-		b2 = backoff * 2
-		maxbackoff = 3600 -- one hour
diff --git a/RemoteDaemon/Transport/Tor.hs b/RemoteDaemon/Transport/Tor.hs
index 5ea06ac2c..20320cadd 100644
--- a/RemoteDaemon/Transport/Tor.hs
+++ b/RemoteDaemon/Transport/Tor.hs
@@ -1,11 +1,11 @@
-{- git-remote-daemon, tor hidden service transport
+{- git-remote-daemon, tor hidden service server and transport
  -
  - Copyright 2016 Joey Hess <id@joeyh.name>
  -
  - Licensed under the GNU GPL version 3 or higher.
  -}
 
-module RemoteDaemon.Transport.Tor (server) where
+module RemoteDaemon.Transport.Tor (server, transport) where
 
 import Common
 import qualified Annex
@@ -16,20 +16,23 @@ import RemoteDaemon.Common
 import Utility.Tor
 import Utility.FileMode
 import Utility.AuthToken
-import P2P.Protocol
+import P2P.Protocol as P2P
 import P2P.IO
 import P2P.Annex
 import P2P.Auth
+import P2P.Address
 import Annex.UUID
 import Types.UUID
 import Messages
 import Git
+import Git.Command
 
 import System.PosixCompat.User
-import Network.Socket
 import Control.Concurrent
 import System.Log.Logger (debugM)
 import Control.Concurrent.STM
+import Control.Concurrent.Async
+import qualified Network.Socket as S
 
 -- Run tor hidden service.
 server :: TransportHandle -> IO ()
@@ -44,17 +47,17 @@ server th@(TransportHandle (LocalRepo r) _) = do
 	let ident = fromUUID u
 	let sock = hiddenServiceSocketFile uid ident
 	nukeFile sock
-	soc <- socket AF_UNIX Stream defaultProtocol
-	bind soc (SockAddrUnix sock)
+	soc <- S.socket S.AF_UNIX S.Stream S.defaultProtocol
+	S.bind soc (S.SockAddrUnix sock)
 	-- Allow everyone to read and write to the socket; tor is probably
 	-- running as a different user. Connections have to authenticate
 	-- to do anything, so it's fine that other local users can connect.
 	modifyFileMode sock $ addModes
 		[groupReadMode, groupWriteMode, otherReadMode, otherWriteMode]
-	listen soc 2
+	S.listen soc 2
 	debugM "remotedaemon" "Tor hidden service running"
 	forever $ do
-		(conn, _) <- accept soc
+		(conn, _) <- S.accept soc
 		h <- setupHandle conn
 		ok <- atomically $ ifM (isFullTBQueue q)
 			( return False
@@ -97,7 +100,7 @@ serveClient th u r q = bracket setup cleanup start
 				, connIhdl = h
 				, connOhdl = h
 				}
-			v <- liftIO $ runNetProto conn $ serveAuth u
+			v <- liftIO $ runNetProto conn $ P2P.serveAuth u
 			case v of
 				Right (Just theiruuid) -> authed conn theiruuid
 				Right Nothing -> liftIO $
@@ -110,7 +113,57 @@ serveClient th u r q = bracket setup cleanup start
 	authed conn theiruuid = 
 		bracket watchChangedRefs (liftIO . stopWatchingChangedRefs) $ \crh -> do
 			v' <- runFullProto (Serving theiruuid crh) conn $
-				serveAuthed u
+				P2P.serveAuthed u
 			case v' of
 				Right () -> return ()
 				Left e -> liftIO $ debugM "remotedaemon" ("Tor connection error: " ++ e)
+
+-- Connect to peer's tor hidden service.
+transport :: Transport
+transport (RemoteRepo r _) url@(RemoteURI uri) th ichan ochan =
+	case unformatP2PAddress (show uri) of
+		Nothing -> return ()
+		Just addr -> robustConnection 1 $ do
+			g <- liftAnnex th Annex.gitRepo
+			bracket (connectPeer g addr) closeConnection (go addr)
+  where
+	go addr conn = do
+		myuuid <- liftAnnex th getUUID
+		authtoken <- fromMaybe nullAuthToken
+			<$> liftAnnex th (loadP2PRemoteAuthToken addr)
+		res <- runNetProto conn $
+			P2P.auth myuuid authtoken
+		case res of
+			Right (Just theiruuid)
+				| getUncachedUUID r == theiruuid -> do
+					send (CONNECTED url)
+					status <- handlecontrol
+						`race` handlepeer conn
+					send (DISCONNECTED url)
+					return $ either id id status
+				| otherwise -> return ConnectionStopping
+			_ -> return ConnectionClosed
+	
+	send msg = atomically $ writeTChan ochan msg
+	
+	handlecontrol = do
+		msg <- atomically $ readTChan ichan
+		case msg of
+			STOP -> return ConnectionStopping
+			LOSTNET -> return ConnectionStopping
+			_ -> handlecontrol
+
+	handlepeer conn = do
+		v <- runNetProto conn P2P.notifyChange
+		case v of
+			Right (Just (ChangedRefs shas)) -> do
+				whenM (checkNewShas th shas) $
+					fetch
+				handlepeer conn
+			_ -> return ConnectionClosed
+	
+	fetch = do
+		send (SYNCING url)
+		ok <- inLocalRepo th $
+			runBool [Param "fetch", Param $ Git.repoDescribe r]
+		send (DONESYNCING url ok)