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|
{-# OPTIONS_GHC -fno-warn-type-defaults #-}
{-# LANGUAGE DuplicateRecordFields #-}
{-# LANGUAGE ExtendedDefaultRules #-}
{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE LambdaCase #-}
{-# LANGUAGE NamedFieldPuns #-}
{-# LANGUAGE NoImplicitPrelude #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE RecordWildCards #-}
{-# LANGUAGE ScopedTypeVariables #-}
{-# LANGUAGE ViewPatterns #-}
module Main where
import Rebase.Prelude hiding (bool, hash, join, o, (<.>))
import Rebase.Data.Text (pack, unpack)
import qualified Rebase.Data.Text as Text
import Development.Shake hiding (getEnv)
import Development.Shake.Command ()
import Development.Shake.FilePath
import Options.Applicative hiding (action, command)
import qualified Options.Applicative as Opt
import ConfigFile
import String
import System.Directory as IO
import System.Directory (createDirectoryIfMissing,
getCurrentDirectory)
import System.Posix.Process (getProcessID)
import System.Posix.Types (CUid (..))
import System.Posix.User (getEffectiveUserID)
noParent :: BaseImageSpecification -> Bool
noParent (EmptyImageOfBytes _) = True
noParent (ParentImageConfigFile _) = False
noParent (SeededImage _ _) = False
dynamicNames :: FilePath -> FilePath
dynamicNames = replace "$(kver)" (snd uname) . replace "$(karch)" (fst uname) . replace "$(debarch)" debarch
chomp :: String -> String
chomp = takeWhile (/= '\n')
debarch :: String
debarch = unsafePerformIO $ do
Stdout out <- cmd "dpkg-architecture -q DEB_BUILD_ARCH"
return $ chomp out
getDebianCodename :: String
getDebianCodename = unsafePerformIO $ do
(Stdout codename) <- cmd "sh -c" [". /etc/os-release && printf '%s' \"$VERSION_CODENAME\""]
return $ if codename == "stretch" then "buster" else codename
uname :: (String, String)
uname = unsafePerformIO $ do
Stdout out <- cmd "sh -c" ["f=$([ -L /vmlinuz ] && readlink /vmlinuz); f=${f##*/vmlinuz-}; echo ${f:-$(uname -r)}"]
pure $ (reverse *** reverse . tail) . break (== '-') . reverse . head . lines $ out
data AptListCfg =
AptListCfg
{ releaseCodename :: String
, architecture :: String
, translationLang :: String
}
{-
TODO: language should derive from $LC_MESSAGES as implemented by apt:
Manual page apt.conf(5)
Languages
The Languages subsection controls which Translation files
are downloaded and in which order APT tries to display
the description-translations. APT will try to display
the first available description in the language which is
listed first. Languages can be defined with their short or
long language codes. Note that not all archives provide
Translation files for every language - the long language
codes are especially rare.
The default list includes "environment" and "en".
"environment" has a special meaning here: it will be
replaced at runtime with the language codes extracted from
the LC_MESSAGES environment variable. It will also ensure
that these codes are not included twice in the list. If
LC_MESSAGES is set to "C" only the Translation-en file (if
available) will be used. To force APT to use no Translation
file use the setting Acquire::Languages=none. "none" is
another special meaning code which will stop the search for
a suitable Translation file. This tells APT to download
these translations too, without actually using them unless
the environment specifies the languages. So the following
example configuration will result in the order "en, de" in an
English locale or "de, en" in a German one. Note that "fr"
is downloaded, but not used unless APT is used in a French
locale (where the order would be "fr, de, en").
Acquire::Languages { "environment"; "de"; "en"; "none";
"fr"; };
Note: To prevent problems resulting from APT being executed
in different environments (e.g. by different users or by
other programs) all Translation files which are found in
/var/lib/apt/lists/ will be added to the end of the list
(after an implicit "none").
-}
language :: String
language = "en"
aptListCfg :: AptListCfg
aptListCfg = AptListCfg getDebianCodename debarch language
aptListFiles :: AptListCfg -> [FilePath]
aptListFiles AptListCfg{..} =
("/var/lib/apt/lists" </>) .
(replace "Translation-en" $ "Translation-" ++ translationLang) .
(replace "amd64" architecture) .
(if (releaseCodename == "stretch" || releaseCodename == "buster")
then replace "-security" "_updates" <$> (replace "bullseye" releaseCodename)
else id) <$> observedCorrectListForBullseye
where
observedCorrectListForBullseye =
[ "httpredir.debian.org_debian_dists_bullseye_InRelease"
, "httpredir.debian.org_debian_dists_bullseye_main_binary-amd64_Packages"
, "httpredir.debian.org_debian_dists_bullseye_main_i18n_Translation-en"
-- , "httpredir.debian.org_debian_dists_sid_InRelease"
-- , "httpredir.debian.org_debian_dists_sid_main_binary-amd64_Packages"
-- , "httpredir.debian.org_debian_dists_sid_main_i18n_Translation-en"
, "security.debian.org_dists_bullseye-security_InRelease"
, "security.debian.org_dists_bullseye-security_main_binary-amd64_Packages"
, "security.debian.org_dists_bullseye-security_main_i18n_Translation-en"
]
buildRoot :: DiskImageConfig -> FilePath -> Action ()
buildRoot config@DiskImageConfig{..} finalOut = do
let out = finalOut <.> "tmp"
mountpoint = finalOut <.> "mnt"
cmd_ "sh -c" ["if mountpoint -q \"$0\"; then umount \"$0\"; fi", mountpoint]
let (abortion :: IO ()) = ignoreErrors' $ do
cmd_ "umount" [mountpoint]
cmd_ "rmdir" [mountpoint]
cmd_ "rm -f" [out]
handle' abortion $ buildInitialImage config mountpoint out
handle' abortion $ do
{- 1. debconf -}
forM_ debconfConfig $
readFile' >=> liftIO . appendFile (mountpoint </> "var/cache/debconf/config.dat")
{- 1.5. install apt package cache -}
when installAptLists $ do
cmd_ "rsync -Ra" (("/./" ++) <$> aptListFiles aptListCfg) (mountpoint ++ "/")
cmd_ "chroot" [mountpoint] "/bin/sh -c" ["apt-cache dumpavail | dpkg --update-avail -"]
{- 2. dpkg installs -}
let (fmap dynamicNames -> debs, packageNames) = partitionPackages $ unpack . coerce <$> toList packages
when (noParent initialImage || not (null packageNames)) $
-- When there is no parent, selfstrap should install packages marked
-- "Required" even if no packages are specified. When there is a parent,
-- assume that this has already happened.
cmd_ "selfstrap" (("--unpack" `consWhen` unpackOnly) ["-t", mountpoint, "--release", releaseCodename aptListCfg]) (dynamicNames <$> packageNames)
when (not $ null debs) $ do
need debs
cmd_ (AddEnv "DEBIAN_FRONTEND" "noninteractive")
["dpkg"] [if unpackOnly then "--unpack" else "--install"] ["--root", mountpoint] debs
{- 3. binaries -}
let go b = do
p <- fromMaybe (fail $ "not found in ${PATH}: " ++ b) <$> liftIO (pathLocate b)
need [p]
cmd_ "cp -L" [p] [mountpoint </> "usr/local/bin" </> takeFileName b]
in do
forM_ (unpack <$> binaries) go
forM_ (unpack <$> optionalBinaries) $ ignoreErrors . go
{- 3.5 skel -}
let go f = when (not $ null f) $ do
homeDir <- getHomeDir
target <- absPath mountpoint <&> (</> "etc/skel")
cmd_ "mkdir -p" [target]
cmd_ (Cwd homeDir) "cp -r --preserve=mode,timestamps -L --parents -t" [target] f
in do
go $ toList (unpack <$> skelFiles)
ignoreErrors . go $ toList (unpack <$> optionalSkelFiles)
{- 3.6 systemd unit files -}
let go s = do
target <- absPath mountpoint <&> (</> "etc/systemd/system")
cmd_ "mkdir -p" [target]
cmd_ "install --preserve-timestamps -m644 -t" [target] [s]
go :: String -> Action ()
in forM_ (unpack <$> unitFiles) go
{- 4. custom setup commands -}
forM_ chrootCommands $ \c -> do
cmd_ "chroot" [mountpoint] "/bin/sh -c" [unpack c]
cmd_ "chroot" [mountpoint] "/bin/sh -c" ["[ $(grep -c '^Package: base-files' /var/lib/dpkg/status) = 1 ]"]
Stdout (pkgList :: String) <- cmd "chroot" [mountpoint] "dpkg -l"
writeFileChanged (finalOut -<.> "pkgs.txt") pkgList
{- 5. create a backup snapshot -}
cmd_ "umount" [mountpoint]
setupLoopDevices out
cmd_ "mount -t btrfs -o subvol=/" [out, mountpoint]
ignoreErrors $ cmd_ (EchoStderr False) "btrfs subvolume delete" [mountpoint </> "root~orig"]
cmd_ "btrfs subvolume snapshot -r" [mountpoint </> "root", mountpoint </> "root~orig"]
-- cleanup
cmd_ "umount" [mountpoint]
cmd_ "rmdir" [mountpoint]
cmd_ "mv" [out, finalOut]
setupLoopDevices :: FilePath -> Action ()
setupLoopDevices out = do
(Stdout devices) <- cmd "sh -c" ["if [ -e \"$0\" ]; then cat \"$0\"; fi ", out -<.> "devices.txt"]
cmd_ "losetup -D"
forM_ (lines devices) $ \d -> cmd_ "losetup -f" [d]
absPath :: MonadIO m => FilePath -> m FilePath
absPath f@('/':_) = return f
absPath f = do
wd <- liftIO getCurrentDirectory
return $ wd </> f
getHomeDir :: Action FilePath
getHomeDir = do
Stdout homeDir <- cmd "sh -c" [script]
return homeDir
where
script = "if [ \"$SUDO_USER\" ]; then getent passwd \"$SUDO_USER\" | cut -z -d: -f6; else printf \"%s\\0\" \"$HOME\"; fi | xargs -0 printf %s"
readFileOptional :: FilePath -> IO (String)
readFileOptional f = IO.doesFileExist f >>= \case
True -> readFile f
False -> return ""
copyParentDevices :: FilePath -> FilePath -> Action ()
copyParentDevices parent out = do
devices <- either (const []) lines . readEither <$> liftIO (readFileOptional (parent <.> "devices.txt"))
writeFile' (out -<.> "devices.txt") (unlines $ parent:devices)
buildInitialImage :: DiskImageConfig -> FilePath -> FilePath -> Action ()
buildInitialImage DiskImageConfig{..} mountpoint out = do
case initialImage of
ParentImageConfigFile f -> do
let cwdParent = f -<.> "btrfs"
buildDirParent = "_build" </> cwdParent
parent <- liftIO (IO.doesFileExist cwdParent) >>= \case
True -> return cwdParent
False -> do
need [buildDirParent]
return buildDirParent
cmd_ "cp --reflink" [parent, out]
cmd_ "mkdir -p" [mountpoint]
cmd_ "sh -c" ["if [ -e \"$0\" ]; then cp \"$0\" \"$1\"; fi", parent <.> "devices.txt", out -<.> "devices.txt"]
ignoreErrors $ do cmd_ "btrfs dev scan -u"
cmd_ "mount -t btrfs" [out] mountpoint
SeededImage n f -> do
let parent = f -<.> "seed.btrfs"
need [parent]
copyParentDevices parent out
-- allocate new image file
cmd_ "rm -f" [out]
cmd_ "truncate -s" [show n, out]
cmd_ "fallocate -l" [show n, out]
setupLoopDevices parent
idempotentMountImage parent mountpoint
addImageToBtrfs out mountpoint
EmptyImageOfBytes n -> do
cmd_ "truncate -s" [show n] [out]
cmd_ "mkfs.btrfs" [out]
cmd_ "mkdir -p" [mountpoint]
setupLoopDevices out
cmd_ "mount -t btrfs" [out] mountpoint
-- create new default subvolume, and then remount with it
createDefaultSubvolume mountpoint
cmd_ "umount" [mountpoint]
cmd_ "mount -t btrfs" [out, mountpoint]
cmd_ (Cwd mountpoint) "mkdir -p var/cache/apt"
cmd_ (Cwd mountpoint) "mkdir -p var/cache/debconf"
cmd_ (Cwd mountpoint) "btrfs subvolume create var/cache/apt/archives"
idempotentSetupLoopDev :: FilePath -> Action (Maybe String)
idempotentSetupLoopDev imageFile = do
deleteLoopDev imageFile
cmd_ "losetup -f" imageFile
getLoopDev imageFile
where
deleteLoopDev = getLoopDev >=> mapM_ (cmd_ "losetup -d")
getLoopDev :: FilePath -> Action (Maybe String)
getLoopDev x = do
Stdout r <- cmd "losetup -n -O name -j" x
return $ guard (r /= "") >> Just r
idempotentMountImage :: FilePath -> FilePath -> Action ()
idempotentMountImage imageFile mountPoint = do
cmd_ "mkdir -p" [mountPoint]
mounted <- cmd "mountpoint -q" [mountPoint] <&> (== ExitSuccess)
when mounted $ cmd_ "umount" [mountPoint]
cmd_ "mount -o compress,ro -t btrfs" [imageFile, mountPoint]
addImageToBtrfs :: FilePath -> FilePath -> Action ()
addImageToBtrfs imageFile mountPoint = do
blockDevice <- idempotentSetupLoopDev imageFile <&>
fromMaybe (error "failed to set up loop device for " ++ imageFile)
cmd_ "btrfs device add" blockDevice mountPoint
cmd_ "mount -o remount,rw,compress" mountPoint
ignoreErrors' :: IO () -> IO ()
ignoreErrors' = flip catch (\(SomeException _) -> return ())
ignoreErrors :: Action () -> Action ()
ignoreErrors = flip actionCatch (\(SomeException _) -> return ())
partitionPackages :: [String] -> ([String], [String])
partitionPackages = partition (".deb" `isSuffixOf`)
consWhen :: a -> Bool -> [a] -> [a]
a `consWhen` c = if c then (a:) else id
strip :: String -> String
strip = unpack . Text.strip . pack
createDefaultSubvolume :: FilePath -> Action ()
createDefaultSubvolume mountpoint = do
cmd_ (Cwd mountpoint) "btrfs subvolume create root"
Stdout subvolIdLine <- cmd (Cwd mountpoint) "sh -c"
["btrfs subvolume show root | sed -n -e 's/^[ \t]*Subvolume ID:[ \t]*//p; s/.*is toplevel subvolume/5/p'"]
let subvolId = strip subvolIdLine
when (null subvolId) $ fail "could not obtain btrfs Subvolume ID"
cmd_ "btrfs subvolume set-default" [strip subvolId, mountpoint]
stripSuffix :: Text -> String -> String
stripSuffix s t = fromMaybe t $ fmap unpack $ Text.stripSuffix s $ pack t
data Options = Options { optCommand :: Command }
data Command = Build BuildOpts | Chroot ChrootOpts
data BuildOpts = BuildOpts { optTarget :: String }
data ChrootOpts = ChrootOpts { optTarget :: String, optChrootCommand :: [String] }
buildOpts :: Parser Command
buildOpts = Build . BuildOpts <$> argument str idm
chrootOpts :: Parser Command
chrootOpts = fmap Chroot $ ChrootOpts <$> argument str idm <*> many (argument str idm)
main :: IO ()
main = customExecParser (prefs showHelpOnEmpty) (info opts desc) >>= run
where
opts :: Parser Options
opts = Options <$> parseCommand
desc = fullDesc <> progDesc detailed <> header "fsmgr - Debian rootfs image manager"
detailed = unwords ["This program generates btrfs filesystem images using 'selfstrap'",
"which, much like 'debootstrap', creates new installations of Debian."]
parseCommand :: Parser Command
parseCommand = subparser $ Opt.command "build" (info' buildOpts buildDesc)
<> Opt.command "chroot" (info' chrootOpts chrootDesc)
buildDesc = ["build the image specified by the YAML config file"]
chrootDesc = ["chroot into the mounted image. ",
"Iff the chroot exits with a success value, filesystem changes will persist"]
info' o d = info (helper <*> o) (progDesc $ unwords d)
run :: Options -> IO ()
run (Options (Build (BuildOpts target))) = earlyFail >> shakeBuildOneImage target
run (Options (Chroot (ChrootOpts target args))) = earlyFail >> chrootImage target args
useCGroups :: Bool
useCGroups = True -- TODO: make command-line option
handle' :: IO b -> Action a -> Action a
handle' = flip actionOnException
ourShakeOptions :: ShakeOptions
ourShakeOptions = shakeOptions {
shakeFiles = "_build",
shakeColor = True,
shakeProgress = progressSimple,
shakeVerbosity = Loud
}
chrootImage :: FilePath -> [String] -> IO ()
chrootImage target args =
shake ourShakeOptions $ do
shakeRules
action $ do
pid <- show <$> liftIO getProcessID
let inp = target -<.> "btrfs"
let tmp = inp <.> "tmp" <.> pid
let mnt = tmp <.> "mnt"
orderOnly [inp]
cmd_ "cp --reflink=always" [inp, tmp]
cmd_ "mkdir" [mnt]
setupLoopDevices target
cmd_ "mount -t btrfs" [tmp, mnt]
let (umount :: IO ()) = do
cmd_ "umount" [mnt]
cmd_ "rm -f" [tmp]
handle' umount $
if useCGroups
then liftIO $ cgroupChroot ("fsmgr" <.> takeFileName target) mnt args
else cmd_ (WithStderr False) "chroot" (mnt : args)
cmd_ "umount" [mnt]
cmd_ "sync"
cmd_ "mv" [tmp, inp]
shakeBuildOneImage :: FilePath -> IO ()
shakeBuildOneImage target =
shake ourShakeOptions $ do
want [target -<.> "btrfs"]
shakeRules
head1 :: String -> String
head1 = lines >>> \case
[] -> ""
x:_ -> x
pathLocate :: String -> IO (Maybe FilePath)
pathLocate c | elem '/' c = pure $ pure c
pathLocate c | True = (getEnv "SUDO_USER" >>=) $ fmap (validatePath . head1 . fromStdout) <$> \case
"" -> cmd "which" [c]
u -> do
path <- fromStdout <$> cmd "su -" [u] "-c" ["printf %s \"$PATH\""]
cmd (AddEnv "PATH" path) "which" [c]
where
validatePath "" = Nothing
validatePath x = Just x
infix 1 ~%>
(~%>) :: FilePattern -> (FilePath -> Action ()) -> Rules ()
filepat ~%> act = phonys f
where
f file | (filepat ?== file) = Just (act file)
f _ = Nothing
cgroupChroot :: String -> FilePath -> [String] -> IO ()
cgroupChroot groupName mnt [] = cgroupChroot groupName mnt ["/bin/bash"]
cgroupChroot groupName mnt args = do
let cgdir = "/sys/fs/cgroup/pids" </> groupName
createDirectoryIfMissing False cgdir
-- TODO: unshare hostname & set from /etc/hostname inside root
cmd_ (Cwd mnt) (WithStderr False)
"unshare --ipc --uts --cgroup --mount --pid --fork chroot ."
"sh -exc" ["mount -t proc proc /proc; mount -t devpts devpts /dev/pts; if [ -e /etc/hostname ]; then hostname -F /etc/hostname; fi; exec \"$@\""]
"sh" args
earlyFail :: IO ()
earlyFail = do
CUid euid <- liftIO getEffectiveUserID
when (euid /= 0) $ fail "you are not root"
Stdout () <- cmd (Traced []) "which selfstrap"
return ()
shakeRules :: Rules ()
shakeRules = do
"_build/*.yaml.canon" %> \out -> do
let yaml = dropDirectory1 $ dropExtension out
need [yaml]
cfg <- readCfg yaml
writeFileChanged out (show cfg)
"_build/*.btrfs" %> \out -> do
let cfgFile = (out -<.> "yaml.canon")
need [cfgFile]
cfg <- readEither <$> readFile' cfgFile
either (error . (("Error parsing file: " ++ cfgFile ++ ": ") ++)) (flip buildRoot out) cfg
priority 2 $ "*.seed.btrfs" %> \out -> do
let tmp = out <.> "tmp"
inp = dropExtension out -<.> ".btrfs"
need [inp]
cmd_ "cp --reflink=always" [inp, tmp]
setupLoopDevices ("_build" </> inp <.> "btrfs")
cmd_ "btrfs-shrink" [tmp]
cmd_ "btrfstune -f -S1" [tmp]
cmd_ (WithStderr False) "mv -i" [tmp, out]
priority 1 $ "*.btrfs" %> \out -> do
need ["_build" </> out]
-- WithStderr False needed for `cp` to interact with the tty
cmd_ (WithStderr False) "cp --reflink=always -i" ["_build" </> out, out]
|