git-annex/Types/GitConfig.hs
Joey Hess 07f1e638ee
annex.securehashesonly
Cryptographically secure hashes can be forced to be used in a repository,
by setting annex.securehashesonly. This does not prevent the git repository
from containing files with insecure hashes, but it does prevent the content
of such files from being pulled into .git/annex/objects from another
repository.

We want to make sure that at no point does git-annex accept content into
.git/annex/objects that is hashed with an insecure key. Here's how it
was done:

* .git/annex/objects/xx/yy/KEY/ is kept frozen, so nothing can be
  written to it normally
* So every place that writes content must call, thawContent or modifyContent.
  We can audit for these, and be sure we've considered all cases.
* The main functions are moveAnnex, and linkToAnnex; these were made to
  check annex.securehashesonly, and are the main security boundary
  for annex.securehashesonly.
* Most other calls to modifyContent deal with other files in the KEY
  directory (inode cache etc). The other ones that mess with the content
  are:
	- Annex.Direct.toDirectGen, in which content already in the
	  annex directory is moved to the direct mode file, so not relevant.
	- fix and lock, which don't add new content
	- Command.ReKey.linkKey, which manually unlocks it to make a
	  copy.
* All other calls to thawContent appear safe.

Made moveAnnex return a Bool, so checked all callsites and made them
deal with a failure in appropriate ways.

linkToAnnex simply returns LinkAnnexFailed; all callsites already deal
with it failing in appropriate ways.

This commit was sponsored by Riku Voipio.
2017-02-27 13:33:59 -04:00

265 lines
9.7 KiB
Haskell

{- git-annex configuration
-
- Copyright 2012-2015 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Types.GitConfig (
Configurable(..),
GitConfig(..),
extractGitConfig,
mergeGitConfig,
RemoteGitConfig(..),
extractRemoteGitConfig,
) where
import Common
import qualified Git
import qualified Git.Config
import qualified Git.Construct
import Git.ConfigTypes
import Utility.DataUnits
import Config.Cost
import Types.UUID
import Types.Distribution
import Types.Availability
import Types.NumCopies
import Types.Difference
import Types.RefSpec
import Utility.HumanTime
import Utility.Gpg (GpgCmd, mkGpgCmd)
import Utility.ThreadScheduler (Seconds(..))
-- | A configurable value, that may not be fully determined yet.
data Configurable a
= HasConfig a
-- ^ Value is fully determined.
| DefaultConfig a
-- ^ A default value is known, but not all config sources
-- have been read yet.
deriving (Show)
{- Main git-annex settings. Each setting corresponds to a git-config key
- such as annex.foo -}
data GitConfig = GitConfig
{ annexVersion :: Maybe String
, annexUUID :: UUID
, annexNumCopies :: Maybe NumCopies
, annexDiskReserve :: Integer
, annexDirect :: Bool
, annexBackends :: [String]
, annexQueueSize :: Maybe Int
, annexBloomCapacity :: Maybe Int
, annexBloomAccuracy :: Maybe Int
, annexSshCaching :: Maybe Bool
, annexAlwaysCommit :: Bool
, annexDelayAdd :: Maybe Int
, annexHttpHeaders :: [String]
, annexHttpHeadersCommand :: Maybe String
, annexAutoCommit :: Configurable Bool
, annexSyncContent :: Configurable Bool
, annexDebug :: Bool
, annexWebOptions :: [String]
, annexQuviOptions :: [String]
, annexAriaTorrentOptions :: [String]
, annexWebDownloadCommand :: Maybe String
, annexCrippledFileSystem :: Bool
, annexLargeFiles :: Maybe String
, annexAddSmallFiles :: Bool
, annexFsckNudge :: Bool
, annexAutoUpgrade :: AutoUpgrade
, annexExpireUnused :: Maybe (Maybe Duration)
, annexSecureEraseCommand :: Maybe String
, annexGenMetaData :: Bool
, annexListen :: Maybe String
, annexStartupScan :: Bool
, annexHardLink :: Bool
, annexThin :: Bool
, annexDifferences :: Differences
, annexUsedRefSpec :: Maybe RefSpec
, annexVerify :: Bool
, annexPidLock :: Bool
, annexPidLockTimeout :: Seconds
, annexAddUnlocked :: Bool
, annexSecureHashesOnly :: Bool
, coreSymlinks :: Bool
, coreSharedRepository :: SharedRepository
, receiveDenyCurrentBranch :: DenyCurrentBranch
, gcryptId :: Maybe String
, gpgCmd :: GpgCmd
}
extractGitConfig :: Git.Repo -> GitConfig
extractGitConfig r = GitConfig
{ annexVersion = notempty $ getmaybe (annex "version")
, annexUUID = maybe NoUUID toUUID $ getmaybe (annex "uuid")
, annexNumCopies = NumCopies <$> getmayberead (annex "numcopies")
, annexDiskReserve = fromMaybe onemegabyte $
readSize dataUnits =<< getmaybe (annex "diskreserve")
, annexDirect = getbool (annex "direct") False
, annexBackends = getwords (annex "backends")
, annexQueueSize = getmayberead (annex "queuesize")
, annexBloomCapacity = getmayberead (annex "bloomcapacity")
, annexBloomAccuracy = getmayberead (annex "bloomaccuracy")
, annexSshCaching = getmaybebool (annex "sshcaching")
, annexAlwaysCommit = getbool (annex "alwayscommit") True
, annexDelayAdd = getmayberead (annex "delayadd")
, annexHttpHeaders = getlist (annex "http-headers")
, annexHttpHeadersCommand = getmaybe (annex "http-headers-command")
, annexAutoCommit = configurable True $
getmaybebool (annex "autocommit")
, annexSyncContent = configurable False $
getmaybebool (annex "synccontent")
, annexDebug = getbool (annex "debug") False
, annexWebOptions = getwords (annex "web-options")
, annexQuviOptions = getwords (annex "quvi-options")
, annexAriaTorrentOptions = getwords (annex "aria-torrent-options")
, annexWebDownloadCommand = getmaybe (annex "web-download-command")
, annexCrippledFileSystem = getbool (annex "crippledfilesystem") False
, annexLargeFiles = getmaybe (annex "largefiles")
, annexAddSmallFiles = getbool (annex "addsmallfiles") True
, annexFsckNudge = getbool (annex "fscknudge") True
, annexAutoUpgrade = toAutoUpgrade $ getmaybe (annex "autoupgrade")
, annexExpireUnused = maybe Nothing Just . parseDuration
<$> getmaybe (annex "expireunused")
, annexSecureEraseCommand = getmaybe (annex "secure-erase-command")
, annexGenMetaData = getbool (annex "genmetadata") False
, annexListen = getmaybe (annex "listen")
, annexStartupScan = getbool (annex "startupscan") True
, annexHardLink = getbool (annex "hardlink") False
, annexThin = getbool (annex "thin") False
, annexDifferences = getDifferences r
, annexUsedRefSpec = either (const Nothing) Just . parseRefSpec
=<< getmaybe (annex "used-refspec")
, annexVerify = getbool (annex "verify") True
, annexPidLock = getbool (annex "pidlock") False
, annexPidLockTimeout = Seconds $ fromMaybe 300 $
getmayberead (annex "pidlocktimeout")
, annexAddUnlocked = getbool (annex "addunlocked") False
, annexSecureHashesOnly = getbool (annex "securehashesonly") False
, coreSymlinks = getbool "core.symlinks" True
, coreSharedRepository = getSharedRepository r
, receiveDenyCurrentBranch = getDenyCurrentBranch r
, gcryptId = getmaybe "core.gcrypt-id"
, gpgCmd = mkGpgCmd (getmaybe "gpg.program")
}
where
getbool k d = fromMaybe d $ getmaybebool k
getmaybebool k = Git.Config.isTrue =<< getmaybe k
getmayberead k = readish =<< getmaybe k
getmaybe k = Git.Config.getMaybe k r
getlist k = Git.Config.getList k r
getwords k = fromMaybe [] $ words <$> getmaybe k
configurable d Nothing = DefaultConfig d
configurable _ (Just v) = HasConfig v
annex k = "annex." ++ k
onemegabyte = 1000000
{- Merge a GitConfig that comes from git-config with one containing
- repository-global defaults. -}
mergeGitConfig :: GitConfig -> GitConfig -> GitConfig
mergeGitConfig gitconfig repoglobals = gitconfig
{ annexAutoCommit = merge annexAutoCommit
, annexSyncContent = merge annexSyncContent
}
where
merge f = case f gitconfig of
HasConfig v -> HasConfig v
DefaultConfig d -> case f repoglobals of
HasConfig v -> HasConfig v
DefaultConfig _ -> HasConfig d
{- Per-remote git-annex settings. Each setting corresponds to a git-config
- key such as <remote>.annex-foo, or if that is not set, a default from
- annex.foo -}
data RemoteGitConfig = RemoteGitConfig
{ remoteAnnexCost :: Maybe Cost
, remoteAnnexCostCommand :: Maybe String
, remoteAnnexIgnore :: Bool
, remoteAnnexSync :: Bool
, remoteAnnexReadOnly :: Bool
, remoteAnnexVerify :: Bool
, remoteAnnexTrustLevel :: Maybe String
, remoteAnnexStartCommand :: Maybe String
, remoteAnnexStopCommand :: Maybe String
, remoteAnnexAvailability :: Maybe Availability
, remoteAnnexBare :: Maybe Bool
{- These settings are specific to particular types of remotes
- including special remotes. -}
, remoteAnnexShell :: Maybe String
, remoteAnnexSshOptions :: [String]
, remoteAnnexRsyncOptions :: [String]
, remoteAnnexRsyncUploadOptions :: [String]
, remoteAnnexRsyncDownloadOptions :: [String]
, remoteAnnexRsyncTransport :: [String]
, remoteAnnexGnupgOptions :: [String]
, remoteAnnexGnupgDecryptOptions :: [String]
, remoteAnnexRsyncUrl :: Maybe String
, remoteAnnexBupRepo :: Maybe String
, remoteAnnexTahoe :: Maybe FilePath
, remoteAnnexBupSplitOptions :: [String]
, remoteAnnexDirectory :: Maybe FilePath
, remoteAnnexGCrypt :: Maybe String
, remoteAnnexDdarRepo :: Maybe String
, remoteAnnexHookType :: Maybe String
, remoteAnnexExternalType :: Maybe String
{- A regular git remote's git repository config. -}
, remoteGitConfig :: Maybe GitConfig
}
extractRemoteGitConfig :: Git.Repo -> String -> RemoteGitConfig
extractRemoteGitConfig r remotename = RemoteGitConfig
{ remoteAnnexCost = getmayberead "cost"
, remoteAnnexCostCommand = notempty $ getmaybe "cost-command"
, remoteAnnexIgnore = getbool "ignore" False
, remoteAnnexSync = getbool "sync" True
, remoteAnnexReadOnly = getbool "readonly" False
, remoteAnnexVerify = getbool "verify" True
, remoteAnnexTrustLevel = notempty $ getmaybe "trustlevel"
, remoteAnnexStartCommand = notempty $ getmaybe "start-command"
, remoteAnnexStopCommand = notempty $ getmaybe "stop-command"
, remoteAnnexAvailability = getmayberead "availability"
, remoteAnnexBare = getmaybebool "bare"
, remoteAnnexShell = getmaybe "shell"
, remoteAnnexSshOptions = getoptions "ssh-options"
, remoteAnnexRsyncOptions = getoptions "rsync-options"
, remoteAnnexRsyncDownloadOptions = getoptions "rsync-download-options"
, remoteAnnexRsyncUploadOptions = getoptions "rsync-upload-options"
, remoteAnnexRsyncTransport = getoptions "rsync-transport"
, remoteAnnexGnupgOptions = getoptions "gnupg-options"
, remoteAnnexGnupgDecryptOptions = getoptions "gnupg-decrypt-options"
, remoteAnnexRsyncUrl = notempty $ getmaybe "rsyncurl"
, remoteAnnexBupRepo = getmaybe "buprepo"
, remoteAnnexTahoe = getmaybe "tahoe"
, remoteAnnexBupSplitOptions = getoptions "bup-split-options"
, remoteAnnexDirectory = notempty $ getmaybe "directory"
, remoteAnnexGCrypt = notempty $ getmaybe "gcrypt"
, remoteAnnexDdarRepo = getmaybe "ddarrepo"
, remoteAnnexHookType = notempty $ getmaybe "hooktype"
, remoteAnnexExternalType = notempty $ getmaybe "externaltype"
, remoteGitConfig = Nothing
}
where
getbool k d = fromMaybe d $ getmaybebool k
getmaybebool k = Git.Config.isTrue =<< getmaybe k
getmayberead k = readish =<< getmaybe k
getmaybe k = mplus (Git.Config.getMaybe (key k) r)
(Git.Config.getMaybe (remotekey k) r)
getoptions k = fromMaybe [] $ words <$> getmaybe k
key k = "annex." ++ k
remotekey k = "remote." ++ remotename ++ ".annex-" ++ k
notempty :: Maybe String -> Maybe String
notempty Nothing = Nothing
notempty (Just "") = Nothing
notempty (Just s) = Just s
instance Default RemoteGitConfig where
def = extractRemoteGitConfig Git.Construct.fromUnknown "dummy"