blob: 82a7fd042e4ade443da5af642a1fad5be8daa4b2 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
|
{- Copyright 2016 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU AGPL version 3 or higher.
-}
{-# LANGUAGE OverloadedStrings #-}
module Storage.Local (localStorage) where
import Types
import Storage
import Serialization ()
import qualified Data.ByteString as B
import qualified Data.ByteString.UTF8 as U8
import Data.Monoid
import Data.List
import System.Posix.User
import System.IO
import System.Directory
import System.Posix
import System.FilePath
import Raaz.Core.Encode
import Control.DeepSeq
import Control.Exception
localStorage :: Storage
localStorage = Storage
{ storeShard = store
, retrieveShard = retrieve
, obscureShards = obscure
, countShards = count
}
store :: StorableObjectIdent -> Shard -> IO StoreResult
store i s = onError (StoreFailure . show) $ do
dir <- shardDir
createDirectoryIfMissing True dir
let dest = dir </> shardFile i
exists <- doesFileExist dest
if exists
then return StoreAlreadyExists
else do
let tmp = dest ++ ".tmp"
fd <- openFd tmp WriteOnly (Just 0o400)
(defaultFileFlags { exclusive = True } )
h <- fdToHandle fd
B.hPut h (toByteString s)
hClose h
renameFile tmp dest
return StoreSuccess
retrieve :: ShardNum -> StorableObjectIdent -> IO RetrieveResult
retrieve n i = onError (RetrieveFailure . show) $ do
dir <- shardDir
fd <- openFd (dir </> shardFile i) ReadOnly Nothing defaultFileFlags
h <- fdToHandle fd
b <- B.hGetContents h
b `deepseq` hClose h
return $ RetrieveSuccess $ Shard n (StorableObject b)
-- | Set atime and mtime to epoch, to obscure access and modification
-- patterns.
--
-- There is no way to set the ctime to the epoch, but setting the other
-- times does at least set it to the current time, which makes all
-- currently stored files look alike.
--
-- Note that the contents of shards is never changed, so it's ok to set the
-- mtime to the epoch; backup programs won't be confused.
obscure :: IO ObscureResult
obscure = onError (ObscureFailure . show) $ do
dir <- shardDir
fs <- filter isShardFile <$> getDirectoryContents dir
mapM_ (\f -> setFileTimes (dir </> f) 0 0) fs
return ObscureSuccess
count :: IO CountResult
count = onError (CountFailure . show) $ do
dir <- shardDir
CountResult . genericLength . filter isShardFile
<$> getDirectoryContents dir
onError :: (IOException -> a) -> IO a -> IO a
onError f a = do
v <- try a
return $ case v of
Left e -> f e
Right r -> r
shardDir :: IO FilePath
shardDir = do
u <- getUserEntryForID =<< getEffectiveUserID
return $ homeDirectory u </> dotdir
shardFile :: StorableObjectIdent -> String
shardFile i = U8.toString (toByteString i) <> ext
ext :: String
ext = ".keysafe"
isShardFile :: FilePath -> Bool
isShardFile f = ext `isSuffixOf` f
dotdir :: FilePath
dotdir = ".keysafe" </> "objects"
|
