factor non-type stuff out of Key

This commit is contained in:
Joey Hess 2017-02-24 13:42:30 -04:00
parent ae3f6705eb
commit ca0daa8bb8
No known key found for this signature in database
GPG key ID: C910D9222512E3C7
10 changed files with 201 additions and 188 deletions

View file

@ -2,7 +2,7 @@ module Annex.Common (module X) where
import Common as X
import Types as X
import Types.Key as X
import Key as X
import Types.UUID as X
import Annex as X (gitRepo, inRepo, fromRepo, calcRepo)
import Annex.Locations as X

View file

@ -23,7 +23,7 @@ import Data.Hash.MD5
import Data.Default
import Common
import Types.Key
import Key
import Types.GitConfig
import Types.Difference
import Utility.FileSystemEncoding

View file

@ -77,7 +77,7 @@ import Data.Char
import Data.Default
import Common
import Types.Key
import Key
import Types.UUID
import Types.GitConfig
import Types.Difference

View file

@ -14,7 +14,7 @@ import Data.Maybe
import Data.Char
import Utility.PartialPrelude
import Types.Key
import Key
import Utility.InodeCache
-- A serialized Key

186
Key.hs Normal file
View file

@ -0,0 +1,186 @@
{- git-annex Keys
-
- Copyright 2011-2017 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU GPL version 3 or higher.
-}
{-# OPTIONS_GHC -fno-warn-orphans #-}
module Key (
Key(..),
AssociatedFile,
stubKey,
key2file,
file2key,
nonChunkKey,
chunkKeyOffset,
isChunkKey,
isKeyPrefix,
prop_isomorphic_key_encode,
prop_isomorphic_key_decode
) where
import Data.Aeson
import Data.Char
import qualified Data.Text as T
import Common
import Types.Key
import Utility.QuickCheck
import Utility.Bloom
import qualified Utility.SimpleProtocol as Proto
stubKey :: Key
stubKey = Key
{ keyName = ""
, keyBackendName = ""
, keySize = Nothing
, keyMtime = Nothing
, keyChunkSize = Nothing
, keyChunkNum = Nothing
}
-- Gets the parent of a chunk key.
nonChunkKey :: Key -> Key
nonChunkKey k = k
{ keyChunkSize = Nothing
, keyChunkNum = Nothing
}
-- Where a chunk key is offset within its parent.
chunkKeyOffset :: Key -> Maybe Integer
chunkKeyOffset k = (*)
<$> keyChunkSize k
<*> (pred <$> keyChunkNum k)
isChunkKey :: Key -> Bool
isChunkKey k = isJust (keyChunkSize k) && isJust (keyChunkNum k)
-- Checks if a string looks like at least the start of a key.
isKeyPrefix :: String -> Bool
isKeyPrefix s = [fieldSep, fieldSep] `isInfixOf` s
fieldSep :: Char
fieldSep = '-'
{- Converts a key to a string that is suitable for use as a filename.
- The name field is always shown last, separated by doubled fieldSeps,
- and is the only field allowed to contain the fieldSep. -}
key2file :: Key -> FilePath
key2file Key { keyBackendName = b, keySize = s, keyMtime = m, keyChunkSize = cs, keyChunkNum = cn, keyName = n } =
b +++ ('s' ?: s) +++ ('m' ?: m) +++ ('S' ?: cs) +++ ('C' ?: cn) +++ (fieldSep : n)
where
"" +++ y = y
x +++ "" = x
x +++ y = x ++ fieldSep:y
f ?: (Just v) = f : show v
_ ?: _ = ""
file2key :: FilePath -> Maybe Key
file2key s
| key == Just stubKey || (keyName <$> key) == Just "" || (keyBackendName <$> key) == Just "" = Nothing
| otherwise = key
where
key = startbackend stubKey s
startbackend k v = sepfield k v addbackend
sepfield k v a = case span (/= fieldSep) v of
(v', _:r) -> findfields r $ a k v'
_ -> Nothing
findfields (c:v) (Just k)
| c == fieldSep = addkeyname k v
| otherwise = sepfield k v $ addfield c
findfields _ v = v
addbackend k v = Just k { keyBackendName = v }
-- This is a strict parser for security reasons; a key
-- can contain only 4 fields, which all consist only of numbers.
-- Any key containing other fields, or non-numeric data is
-- rejected with Nothing.
--
-- If a key contained non-numeric fields, they could be used to
-- embed data used in a SHA1 collision attack, which would be a
-- problem since the keys are committed to git.
addfield _ _ v | not (all isDigit v) = Nothing
addfield 's' k v = do
sz <- readish v
return $ k { keySize = Just sz }
addfield 'm' k v = do
mtime <- readish v
return $ k { keyMtime = Just mtime }
addfield 'S' k v = do
chunksize <- readish v
return $ k { keyChunkSize = Just chunksize }
addfield 'C' k v = case readish v of
Just chunknum | chunknum > 0 ->
return $ k { keyChunkNum = Just chunknum }
_ -> Nothing
addfield _ _ _ = Nothing
addkeyname k v
| validKeyName k v = Just $ k { keyName = v }
| otherwise = Nothing
{- A key with a backend ending in "E" is an extension preserving key,
- using some hash.
-
- The length of the extension is limited in order to mitigate against
- SHA1 collision attacks (specifically, chosen-prefix attacks).
- In such an attack, the extension of the key could be made to contain
- the collision generation data, with the result that a signed git commit
- including such keys would not be secure.
-
- The maximum extension length ever generated for such a key was 8
- characters; 20 is used here to give a little future wiggle-room.
- The SHA1 common-prefix attack used 128 bytes of data.
-
- This code is here, and not in Backend.Hash (where it really belongs)
- so that file2key can check it whenever a Key is constructed.
-}
validKeyName :: Key -> String -> Bool
validKeyName k v
| end (keyBackendName k) == "E" = length (takeExtensions v) <= 20
| otherwise = True
instance Arbitrary Key where
arbitrary = Key
<$> (listOf1 $ elements $ ['A'..'Z'] ++ ['a'..'z'] ++ ['0'..'9'] ++ "-_\r\n \t")
<*> (listOf1 $ elements ['A'..'Z']) -- BACKEND
<*> ((abs <$>) <$> arbitrary) -- size cannot be negative
<*> arbitrary
<*> ((abs <$>) <$> arbitrary) -- chunksize cannot be negative
<*> ((succ . abs <$>) <$> arbitrary) -- chunknum cannot be 0 or negative
instance Hashable Key where
hashIO32 = hashIO32 . key2file
hashIO64 = hashIO64 . key2file
instance ToJSON Key where
toJSON = toJSON . key2file
instance FromJSON Key where
parseJSON (String t) = maybe mempty pure $ file2key $ T.unpack t
parseJSON _ = mempty
instance Proto.Serializable Key where
serialize = key2file
deserialize = file2key
prop_isomorphic_key_encode :: Key -> Bool
prop_isomorphic_key_encode k = Just k == (file2key . key2file) k
prop_isomorphic_key_decode :: FilePath -> Bool
prop_isomorphic_key_decode f
| normalfieldorder = maybe True (\k -> key2file k == f) (file2key f)
| otherwise = True
where
-- file2key will accept the fields in any order, so don't
-- try the test unless the fields are in the normal order
normalfieldorder = fields `isPrefixOf` "smSC"
fields = map (f !!) $ filter (< length f) $ map succ $
elemIndices fieldSep f

View file

@ -36,7 +36,7 @@ import Data.Maybe
import Data.Monoid
import Prelude
import Types.Key
import Key
import Utility.Metered
import Utility.Percentage

14
Test.hs
View file

@ -63,7 +63,7 @@ import qualified Logs.Presence
import qualified Logs.PreferredContent
import qualified Types.MetaData
import qualified Remote
import qualified Types.Key
import qualified Key
import qualified Types.Messages
import qualified Config
import qualified Config.Cost
@ -152,8 +152,8 @@ properties = localOption (QuickCheckTests 1000) $ testGroup "QuickCheck"
[ testProperty "prop_isomorphic_deencode_git" Git.Filename.prop_isomorphic_deencode
, testProperty "prop_isomorphic_deencode" Utility.Format.prop_isomorphic_deencode
, testProperty "prop_isomorphic_fileKey" Annex.Locations.prop_isomorphic_fileKey
, testProperty "prop_isomorphic_key_encode" Types.Key.prop_isomorphic_key_encode
, testProperty "prop_isomorphic_key_decode" Types.Key.prop_isomorphic_key_decode
, testProperty "prop_isomorphic_key_encode" Key.prop_isomorphic_key_encode
, testProperty "prop_isomorphic_key_decode" Key.prop_isomorphic_key_decode
, testProperty "prop_isomorphic_shellEscape" Utility.SafeCommand.prop_isomorphic_shellEscape
, testProperty "prop_isomorphic_shellEscape_multiword" Utility.SafeCommand.prop_isomorphic_shellEscape_multiword
, testProperty "prop_isomorphic_configEscape" Logs.Remote.prop_isomorphic_configEscape
@ -390,7 +390,7 @@ test_reinject = intmpclonerepoInDirect $ do
git_annex "drop" ["--force", sha1annexedfile] @? "drop failed"
annexed_notpresent sha1annexedfile
writeFile tmp $ content sha1annexedfile
key <- Types.Key.key2file <$> getKey backendSHA1 tmp
key <- Key.key2file <$> getKey backendSHA1 tmp
git_annex "reinject" [tmp, sha1annexedfile] @? "reinject failed"
annexed_present sha1annexedfile
-- fromkey can't be used on a crippled filesystem, since it makes a
@ -846,9 +846,9 @@ test_unused = intmpclonerepoInDirect $ do
checkunused [annexedfilekey, sha1annexedfilekey] "after rm sha1annexedfile"
-- good opportunity to test dropkey also
git_annex "dropkey" ["--force", Types.Key.key2file annexedfilekey]
git_annex "dropkey" ["--force", Key.key2file annexedfilekey]
@? "dropkey failed"
checkunused [sha1annexedfilekey] ("after dropkey --force " ++ Types.Key.key2file annexedfilekey)
checkunused [sha1annexedfilekey] ("after dropkey --force " ++ Key.key2file annexedfilekey)
not <$> git_annex "dropunused" ["1"] @? "dropunused failed to fail without --force"
git_annex "dropunused" ["--force", "1"] @? "dropunused failed"
@ -1959,7 +1959,7 @@ checklocationlog f expected = do
case r of
Just k -> do
uuids <- annexeval $ Remote.keyLocations k
assertEqual ("bad content in location log for " ++ f ++ " key " ++ Types.Key.key2file k ++ " uuid " ++ show thisuuid)
assertEqual ("bad content in location log for " ++ f ++ " key " ++ Key.key2file k ++ " uuid " ++ show thisuuid)
expected (thisuuid `elem` uuids)
_ -> assertFailure $ f ++ " failed to look up key"

View file

@ -9,7 +9,7 @@
module Types.ActionItem where
import Types.Key
import Key
import Types.Transfer
import Git.FilePath

View file

@ -5,30 +5,9 @@
- Licensed under the GNU GPL version 3 or higher.
-}
module Types.Key (
Key(..),
AssociatedFile,
stubKey,
key2file,
file2key,
nonChunkKey,
chunkKeyOffset,
isChunkKey,
isKeyPrefix,
prop_isomorphic_key_encode,
prop_isomorphic_key_decode
) where
module Types.Key where
import System.Posix.Types
import Data.Aeson
import Data.Char
import qualified Data.Text as T
import Common
import Utility.QuickCheck
import Utility.Bloom
import qualified Utility.SimpleProtocol as Proto
{- A Key has a unique name, which is derived from a particular backend,
- and may contain other optional metadata. -}
@ -43,156 +22,3 @@ data Key = Key
{- A filename may be associated with a Key. -}
type AssociatedFile = Maybe FilePath
stubKey :: Key
stubKey = Key
{ keyName = ""
, keyBackendName = ""
, keySize = Nothing
, keyMtime = Nothing
, keyChunkSize = Nothing
, keyChunkNum = Nothing
}
-- Gets the parent of a chunk key.
nonChunkKey :: Key -> Key
nonChunkKey k = k
{ keyChunkSize = Nothing
, keyChunkNum = Nothing
}
-- Where a chunk key is offset within its parent.
chunkKeyOffset :: Key -> Maybe Integer
chunkKeyOffset k = (*)
<$> keyChunkSize k
<*> (pred <$> keyChunkNum k)
isChunkKey :: Key -> Bool
isChunkKey k = isJust (keyChunkSize k) && isJust (keyChunkNum k)
-- Checks if a string looks like at least the start of a key.
isKeyPrefix :: String -> Bool
isKeyPrefix s = [fieldSep, fieldSep] `isInfixOf` s
fieldSep :: Char
fieldSep = '-'
{- Converts a key to a string that is suitable for use as a filename.
- The name field is always shown last, separated by doubled fieldSeps,
- and is the only field allowed to contain the fieldSep. -}
key2file :: Key -> FilePath
key2file Key { keyBackendName = b, keySize = s, keyMtime = m, keyChunkSize = cs, keyChunkNum = cn, keyName = n } =
b +++ ('s' ?: s) +++ ('m' ?: m) +++ ('S' ?: cs) +++ ('C' ?: cn) +++ (fieldSep : n)
where
"" +++ y = y
x +++ "" = x
x +++ y = x ++ fieldSep:y
f ?: (Just v) = f : show v
_ ?: _ = ""
file2key :: FilePath -> Maybe Key
file2key s
| key == Just stubKey || (keyName <$> key) == Just "" || (keyBackendName <$> key) == Just "" = Nothing
| otherwise = key
where
key = startbackend stubKey s
startbackend k v = sepfield k v addbackend
sepfield k v a = case span (/= fieldSep) v of
(v', _:r) -> findfields r $ a k v'
_ -> Nothing
findfields (c:v) (Just k)
| c == fieldSep = addkeyname k v
| otherwise = sepfield k v $ addfield c
findfields _ v = v
addbackend k v = Just k { keyBackendName = v }
-- This is a strict parser for security reasons; a key
-- can contain only 4 fields, which all consist only of numbers.
-- Any key containing other fields, or non-numeric data is
-- rejected with Nothing.
--
-- If a key contained non-numeric fields, they could be used to
-- embed data used in a SHA1 collision attack, which would be a
-- problem since the keys are committed to git.
addfield _ _ v | not (all isDigit v) = Nothing
addfield 's' k v = do
sz <- readish v
return $ k { keySize = Just sz }
addfield 'm' k v = do
mtime <- readish v
return $ k { keyMtime = Just mtime }
addfield 'S' k v = do
chunksize <- readish v
return $ k { keyChunkSize = Just chunksize }
addfield 'C' k v = case readish v of
Just chunknum | chunknum > 0 ->
return $ k { keyChunkNum = Just chunknum }
_ -> Nothing
addfield _ _ _ = Nothing
addkeyname k v
| validKeyName k v = Just $ k { keyName = v }
| otherwise = Nothing
{- A key with a backend ending in "E" is an extension preserving key,
- using some hash.
-
- The length of the extension is limited in order to mitigate against
- SHA1 collision attacks (specifically, chosen-prefix attacks).
- In such an attack, the extension of the key could be made to contain
- the collision generation data, with the result that a signed git commit
- including such keys would not be secure.
-
- The maximum extension length ever generated for such a key was 8
- characters; 20 is used here to give a little future wiggle-room.
- The SHA1 common-prefix attack used 128 bytes of data.
-
- This code is here, and not in Backend.Hash (where it really belongs)
- so that file2key can check it whenever a Key is constructed.
-}
validKeyName :: Key -> String -> Bool
validKeyName k v
| end (keyBackendName k) == "E" = length (takeExtensions v) <= 20
| otherwise = True
instance ToJSON Key where
toJSON = toJSON . key2file
instance FromJSON Key where
parseJSON (String t) = maybe mempty pure $ file2key $ T.unpack t
parseJSON _ = mempty
instance Proto.Serializable Key where
serialize = key2file
deserialize = file2key
instance Arbitrary Key where
arbitrary = Key
<$> (listOf1 $ elements $ ['A'..'Z'] ++ ['a'..'z'] ++ ['0'..'9'] ++ "-_\r\n \t")
<*> (listOf1 $ elements ['A'..'Z']) -- BACKEND
<*> ((abs <$>) <$> arbitrary) -- size cannot be negative
<*> arbitrary
<*> ((abs <$>) <$> arbitrary) -- chunksize cannot be negative
<*> ((succ . abs <$>) <$> arbitrary) -- chunknum cannot be 0 or negative
instance Hashable Key where
hashIO32 = hashIO32 . key2file
hashIO64 = hashIO64 . key2file
prop_isomorphic_key_encode :: Key -> Bool
prop_isomorphic_key_encode k = Just k == (file2key . key2file) k
prop_isomorphic_key_decode :: FilePath -> Bool
prop_isomorphic_key_decode f
| normalfieldorder = maybe True (\k -> key2file k == f) (file2key f)
| otherwise = True
where
-- file2key will accept the fields in any order, so don't
-- try the test unless the fields are in the normal order
normalfieldorder = fields `isPrefixOf` "smSC"
fields = map (f !!) $ filter (< length f) $ map succ $
elemIndices fieldSep f

View file

@ -848,6 +848,7 @@ Executable git-annex
Git.UpdateIndex
Git.Url
Git.Version
Key
Limit
Limit.Wanted
Logs