git-annex/Command/ReKey.hs
Joey Hess b657242f5d
enforce retrievalSecurityPolicy
Leveraged the existing verification code by making it also check the
retrievalSecurityPolicy.

Also, prevented getViaTmp from running the download action at all when the
retrievalSecurityPolicy is going to prevent verifying and so storing it.

Added annex.security.allow-unverified-downloads. A per-remote version
would be nice to have too, but would need more plumbing, so KISS.
(Bill the Cat reference not too over the top I hope. The point is to
make this something the user reads the documentation for before using.)

A few calls to verifyKeyContent and getViaTmp, that don't
involve downloads from remotes, have RetrievalAllKeysSecure hard-coded.
It was also hard-coded for P2P.Annex and Command.RecvKey,
to match the values of the corresponding remotes.

A few things use retrieveKeyFile/retrieveKeyFileCheap without going
through getViaTmp.
* Command.Fsck when downloading content from a remote to verify it.
  That content does not get into the annex, so this is ok.
* Command.AddUrl when using a remote to download an url; this is new
  content being added, so this is ok.

This commit was sponsored by Fernando Jimenez on Patreon.
2018-06-21 13:37:01 -04:00

131 lines
4 KiB
Haskell

{- git-annex command
-
- Copyright 2012-2016 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU GPL version 3 or higher.
-}
module Command.ReKey where
import Command
import qualified Annex
import Annex.Content
import Annex.Ingest
import Annex.Link
import Annex.Perms
import Annex.ReplaceFile
import Logs.Location
import Git.FilePath
import qualified Database.Keys
import Annex.InodeSentinal
import Utility.InodeCache
cmd :: Command
cmd = notDirect $
command "rekey" SectionPlumbing
"change keys used for files"
(paramRepeating $ paramPair paramPath paramKey)
(seek <$$> optParser)
data ReKeyOptions = ReKeyOptions
{ reKeyThese :: CmdParams
, batchOption :: BatchMode
}
optParser :: CmdParamsDesc -> Parser ReKeyOptions
optParser desc = ReKeyOptions
<$> cmdParams desc
<*> parseBatchOption
-- Split on the last space, since a FilePath can contain whitespace,
-- but a Key very rarely does.
batchParser :: String -> Either String (FilePath, Key)
batchParser s = case separate (== ' ') (reverse s) of
(rk, rf)
| null rk || null rf -> Left "Expected: \"file key\""
| otherwise -> case file2key (reverse rk) of
Nothing -> Left "bad key"
Just k -> Right (reverse rf, k)
seek :: ReKeyOptions -> CommandSeek
seek o = case batchOption o of
Batch -> batchInput batchParser (batchCommandAction . start)
NoBatch -> withPairs (start . parsekey) (reKeyThese o)
where
parsekey (file, skey) =
(file, fromMaybe (giveup "bad key") (file2key skey))
start :: (FilePath, Key) -> CommandStart
start (file, newkey) = ifAnnexed file go stop
where
go oldkey
| oldkey == newkey = stop
| otherwise = do
showStart "rekey" file
next $ perform file oldkey newkey
perform :: FilePath -> Key -> Key -> CommandPerform
perform file oldkey newkey = do
ifM (inAnnex oldkey)
( unlessM (linkKey file oldkey newkey) $
giveup "failed"
, unlessM (Annex.getState Annex.force) $
giveup $ file ++ " is not available (use --force to override)"
)
next $ cleanup file oldkey newkey
{- Make a hard link to the old key content (when supported),
- to avoid wasting disk space. -}
linkKey :: FilePath -> Key -> Key -> Annex Bool
linkKey file oldkey newkey = ifM (isJust <$> isAnnexLink file)
{- If the object file is already hardlinked to elsewhere, a hard
- link won't be made by getViaTmpFromDisk, but a copy instead.
- This avoids hard linking to content linked to an
- unlocked file, which would leave the new key unlocked
- and vulnerable to corruption. -}
( getViaTmpFromDisk RetrievalAllKeysSecure DefaultVerify newkey $ \tmp -> unVerified $ do
oldobj <- calcRepo (gitAnnexLocation oldkey)
linkOrCopy' (return True) newkey oldobj tmp Nothing
, do
ic <- withTSDelta (liftIO . genInodeCache file)
{- The file being rekeyed is itself an unlocked file, so if
- it's linked to the old key, that link must be broken. -}
oldobj <- calcRepo (gitAnnexLocation oldkey)
v <- tryNonAsync $ modifyContent oldobj $ do
replaceFile oldobj $ \tmp ->
unlessM (checkedCopyFile oldkey file tmp Nothing) $
error "can't lock old key"
freezeContent oldobj
oldic <- withTSDelta (liftIO . genInodeCache oldobj)
whenM (isUnmodified oldkey oldobj) $
Database.Keys.addInodeCaches oldkey (catMaybes [oldic])
case v of
Left e -> do
warning (show e)
return False
Right () -> do
r <- linkToAnnex newkey file ic
return $ case r of
LinkAnnexFailed -> False
LinkAnnexOk -> True
LinkAnnexNoop -> True
)
cleanup :: FilePath -> Key -> Key -> CommandCleanup
cleanup file oldkey newkey = do
ifM (isJust <$> isAnnexLink file)
( do
-- Update symlink to use the new key.
liftIO $ removeFile file
addLink file newkey Nothing
, do
mode <- liftIO $ catchMaybeIO $ fileMode <$> getFileStatus file
liftIO $ whenM (isJust <$> isPointerFile file) $
writePointerFile file newkey mode
stagePointerFile file mode =<< hashPointerFile newkey
Database.Keys.removeAssociatedFile oldkey
=<< inRepo (toTopFilePath file)
)
whenM (inAnnex newkey) $
logStatus newkey InfoPresent
return True