use socket for tor hidden service

This avoids needing to bind to the right port before something else
does.

The socket is in /var/run/user/$uid/ which ought to be writable by only
that uid. At least it is on linux systems using systemd.

For Windows, may need to revisit this and use ports or something.

The first version of tor to support sockets for hidden services
was 0.2.6.3. That is not in Debian stable, but is available in
backports.

This commit was sponsored by andrea rota.

Command/EnableTor.hs

@@ -10,19 +10,25 @@ module Command.EnableTor where
 import Command
 import Utility.Tor
 
+-- This runs as root, so avoid making any commits or initializing
+-- git-annex, as that would create root-owned files.
 cmd :: Command
 cmd = noCommit $ dontCheck repoExists $
 	command "enable-tor" SectionPlumbing ""
-		paramNumber (withParams seek)
+		"userid uuid" (withParams seek)
 
 seek :: CmdParams -> CommandSeek
 seek = withWords start
 
 start :: CmdParams -> CommandStart
-start (localport:[]) = case readish localport of
-	Nothing -> error "Bad localport"
-	Just lp -> do
-		(onionaddr, onionport) <- liftIO $ addHiddenService lp
-		liftIO $ putStrLn (onionaddr ++ ":" ++ show onionport)
+start (suserid:uuid:[]) = case readish suserid of
+	Nothing -> error "Bad userid"
+	Just userid -> do
+		(onionaddr, onionport, onionsocket) <- liftIO $
+			addHiddenService userid uuid
+		liftIO $ putStrLn $
+			onionaddr ++ ":" ++ 
+			show onionport ++ " " ++
+			show onionsocket
 		stop
-start _ = error "Need 1 localport parameter"
+start _ = error "Bad params"