Added git-remote-tor-annex, which allows git pull and push to the tor hidden service.

Almost working, but there's a bug in the relaying.

Also, made tor hidden service setup pick a random port, to make it harder
to port scan.

This commit was sponsored by Boyd Stephen Smith Jr. on Patreon.

CmdLine/GitRemoteTorAnnex.hs

@@ -0,0 +1,62 @@
+{- git-remote-tor-annex program
+ -
+ - Copyright 2016 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module CmdLine.GitRemoteTorAnnex where
+
+import Common
+import qualified Annex
+import qualified Git.CurrentRepo
+import Remote.Helper.P2P
+import Remote.Helper.P2P.IO
+import Remote.Helper.Tor
+import Utility.Tor
+import Annex.UUID
+
+run :: [String] -> IO ()
+run (_remotename:address:[]) = forever $ do
+	-- gitremote-helpers protocol
+	l <- getLine
+	case l of
+		"capabilities" -> do
+			putStrLn "connect"
+			putStrLn ""
+		"connect git-upload-pack" -> go UploadPack
+		"connect git-receive-pack" -> go ReceivePack
+		_ -> error $ "git-remote-helpers protocol error at " ++ show l
+  where
+	(onionaddress, onionport)
+		| '/' `elem` address = parseAddressPort $
+			reverse $ takeWhile (/= '/') $ reverse address
+		| otherwise = parseAddressPort address
+	go service = do
+		putStrLn ""
+		hFlush stdout
+		connectService onionaddress onionport service >>= exitWith
+run (_remotename:[]) = giveup "remote address not configured"
+run _ = giveup "expected remote name and address parameters"
+
+parseAddressPort :: String -> (OnionAddress, OnionPort)
+parseAddressPort s = 
+	let (a, sp) = separate (== ':') s
+	in case readish sp of
+		Nothing -> giveup "onion address must include port number"
+		Just p -> (OnionAddress a, p)
+
+connectService :: OnionAddress -> OnionPort -> Service -> IO ExitCode
+connectService address port service = do
+	state <- Annex.new =<< Git.CurrentRepo.get
+	Annex.eval state $ do
+		authtoken <- fromMaybe nullAuthToken
+			<$> getTorAuthToken address
+		myuuid <- getUUID
+		g <- Annex.gitRepo
+		h <- liftIO $ torHandle =<< connectHiddenService address port
+		runNetProtoHandle h h g $ do
+			v <- auth myuuid authtoken
+			case v of
+				Just _theiruuid -> connect service stdin stdout
+				Nothing -> giveup $ "authentication failed, perhaps you need to set " ++ torAuthTokenEnv