module Propellor.Property.Systemd ( module Propellor.Property.Systemd.Core, started, stopped, enabled, disabled, persistentJournal, daemonReloaded, Container, container, nspawned, containerCfg, resolvConfed, ) where import Propellor import Propellor.Types.Chroot import qualified Propellor.Property.Chroot as Chroot import qualified Propellor.Property.Apt as Apt import qualified Propellor.Property.File as File import Propellor.Property.Systemd.Core import Utility.SafeCommand import Utility.FileMode import Data.List import Data.List.Utils import qualified Data.Map as M type ServiceName = String type MachineName = String data Container = Container MachineName Chroot.Chroot Host deriving (Show) instance Hostlike Container where (Container n c h) & p = Container n c (h & p) (Container n c h) &^ p = Container n c (h &^ p) getHost (Container _ _ h) = h -- | Starts a systemd service. started :: ServiceName -> Property started n = trivial $ cmdProperty "systemctl" ["start", n] `describe` ("service " ++ n ++ " started") -- | Stops a systemd service. stopped :: ServiceName -> Property stopped n = trivial $ cmdProperty "systemctl" ["stop", n] `describe` ("service " ++ n ++ " stopped") -- | Enables a systemd service. enabled :: ServiceName -> Property enabled n = trivial $ cmdProperty "systemctl" ["enable", n] `describe` ("service " ++ n ++ " enabled") -- | Disables a systemd service. disabled :: ServiceName -> Property disabled n = trivial $ cmdProperty "systemctl" ["disable", n] `describe` ("service " ++ n ++ " disabled") -- | Enables persistent storage of the journal. persistentJournal :: Property persistentJournal = check (not <$> doesDirectoryExist dir) $ combineProperties "persistent systemd journal" [ cmdProperty "install" ["-d", "-g", "systemd-journal", dir] , cmdProperty "setfacl" ["-R", "-nm", "g:adm:rx,d:g:adm:rx", dir] , started "systemd-journal-flush" ] `requires` Apt.installed ["acl"] where dir = "/var/log/journal" -- | Causes systemd to reload its configuration files. daemonReloaded :: Property daemonReloaded = trivial $ cmdProperty "systemctl" ["daemon-reload"] -- | Defines a container with a given machine name. -- -- Properties can be added to configure the Container. -- -- > container "webserver" (Chroot.debootstrapped (System (Debian Unstable) "amd64") mempty) -- > & Apt.installedRunning "apache2" -- > & ... container :: MachineName -> (FilePath -> Chroot.Chroot) -> Container container name mkchroot = Container name c h & os system & resolvConfed where c@(Chroot.Chroot _ system _ _) = mkchroot (containerDir name) h = Host name [] mempty -- | Runs a container using systemd-nspawn. -- -- A systemd unit is set up for the container, so it will automatically -- be started on boot. -- -- Systemd is automatically installed inside the container, and will -- communicate with the host's systemd. This allows systemctl to be used to -- examine the status of services running inside the container. -- -- When the host system has persistentJournal enabled, journactl can be -- used to examine logs forwarded from the container. -- -- Reverting this property stops the container, removes the systemd unit, -- and deletes the chroot and all its contents. nspawned :: Container -> RevertableProperty nspawned c@(Container name (Chroot.Chroot loc system builderconf _) h) = RevertableProperty setup teardown where setup = combineProperties ("nspawned " ++ name) $ map toProp steps ++ [containerprovisioned] teardown = combineProperties ("not nspawned " ++ name) $ map (toProp . revert) (reverse steps) steps = [ enterScript c , chrootprovisioned , nspawnService c (_chrootCfg $ _chrootinfo $ hostInfo h) ] -- Chroot provisioning is run in systemd-only mode, -- which sets up the chroot and ensures systemd and dbus are -- installed, but does not handle the other provisions. chrootprovisioned = Chroot.provisioned' (Chroot.propigateChrootInfo chroot) chroot True -- Use nsenter to enter container and and run propellor to -- finish provisioning. containerprovisioned = Chroot.propellChroot chroot (enterContainerProcess c) False chroot = Chroot.Chroot loc system builderconf h -- | Sets up the service file for the container, and then starts -- it running. nspawnService :: Container -> ChrootCfg -> RevertableProperty nspawnService (Container name _ _) cfg = RevertableProperty setup teardown where service = nspawnServiceName name servicefile = "/etc/systemd/system/multi-user.target.wants" service servicefilecontent = do ls <- lines <$> readFile "/lib/systemd/system/systemd-nspawn@.service" return $ unlines $ "# deployed by propellor" : map addparams ls addparams l | "ExecStart=" `isPrefixOf` l = l ++ " " ++ unwords (nspawnServiceParams cfg) | otherwise = l goodservicefile = (==) <$> servicefilecontent <*> catchDefaultIO "" (readFile servicefile) writeservicefile = property servicefile $ makeChange $ viaTmp writeFile servicefile =<< servicefilecontent setupservicefile = check (not <$> goodservicefile) $ -- if it's running, it has the wrong configuration, -- so stop it stopped service `requires` daemonReloaded `requires` writeservicefile setup = started service `requires` setupservicefile teardown = check (doesFileExist servicefile) $ disabled service `requires` stopped service nspawnServiceParams :: ChrootCfg -> [String] nspawnServiceParams NoChrootCfg = [] nspawnServiceParams (SystemdNspawnCfg ps) = M.keys $ M.filter id $ M.fromList ps -- | Installs a "enter-machinename" script that root can use to run a -- command inside the container. -- -- This uses nsenter to enter the container, by looking up the pid of the -- container's init process and using its namespace. enterScript :: Container -> RevertableProperty enterScript c@(Container name _ _) = RevertableProperty setup teardown where setup = combineProperties ("generated " ++ enterScriptFile c) [ scriptfile `File.hasContent` [ "#!/bin/sh" , "# Generated by propellor" , "pid=\"$(machinectl show " ++ shellEscape name ++ " -p Leader | cut -d= -f2)\" || true" , "if [ -n \"$pid\" ]; then" , "\tnsenter -p -u -n -i -m -t \"$pid\" \"$@\"" , "else" , "\techo container not running >&2" , "\texit 1" , "fi" ] , scriptfile `File.mode` combineModes (readModes ++ executeModes) ] teardown = File.notPresent scriptfile scriptfile = enterScriptFile c enterScriptFile :: Container -> FilePath enterScriptFile (Container name _ _ ) = "/usr/local/bin/enter-" ++ mungename name enterContainerProcess :: Container -> [String] -> CreateProcess enterContainerProcess = proc . enterScriptFile nspawnServiceName :: MachineName -> ServiceName nspawnServiceName name = "systemd-nspawn@" ++ name ++ ".service" containerDir :: MachineName -> FilePath containerDir name = "/var/lib/container" mungename name mungename :: MachineName -> String mungename = replace "/" "_" -- | This configures how systemd-nspawn(1) starts the container, -- by specifying a parameter, such as "--private-network", or -- "--link-journal=guest" -- -- When there is no leading dash, "--" is prepended to the parameter. -- -- Reverting the property will remove a parameter, if it's present. containerCfg :: String -> RevertableProperty containerCfg p = RevertableProperty (mk True) (mk False) where mk b = pureInfoProperty ("container configuration " ++ (if b then "" else "without ") ++ p') $ mempty { _chrootinfo = mempty { _chrootCfg = SystemdNspawnCfg [(p', b)] } } p' = case p of ('-':_) -> p _ -> "--" ++ p -- | Bind mounts from the host into the container. -- -- This property is enabled by default. Revert it to disable it. resolvConfed :: RevertableProperty resolvConfed = containerCfg "bind=/etc/resolv.conf"