blob: 226fac734e60094fe78b3366d987074cd0060fb8 (
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
|
{-# LANGUAGE OverloadedStrings #-}
{- Copyright 2016 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU AGPL version 3 or higher.
-}
module ExpensiveHash where
import Types
import Tunables
import Cost
import Serialization ()
import qualified Data.Text as T
import qualified Data.ByteString as B
import qualified Crypto.Argon2 as Argon2
import Raaz.Core.Encode
import Data.Time.Clock
import Control.DeepSeq
import Data.Monoid
-- | A hash that is expensive to calculate.
--
-- This is a lynchpin of keysafe's security, because using this hash
-- as an encryption key forces brute force attackers to generate
-- hashes over and over again, taking a very long time.
data ExpensiveHash = ExpensiveHash (Cost CreationOp) T.Text
deriving (Show)
data Salt t = Salt t
-- | Would rather use haskell argon2 library, but it doesn't build
-- from source, and is buggy. https://github.com/ocharles/argon2/issues/3
expensiveHash :: Encodable t => Tunables -> Salt t -> B.ByteString -> ExpensiveHash
expensiveHash tunables (Salt s) b =
case expensiveHashTunable tunables of
UseArgon2 opts cost -> ExpensiveHash cost $
-- Using hashEncoded here and not hash,
-- because of this bug:
-- https://github.com/ocharles/argon2/issues/3
Argon2.hashEncoded opts b argonsalt
where
-- argon salt cannot be shorter than 8 bytes, so pad with spaces.
argonsalt =
let sb = toByteString s
in sb <> B.replicate (8 - B.length sb ) 32
benchmarkExpensiveHash :: Tunables -> IO (Benchmark (Cost CreationOp))
benchmarkExpensiveHash tunables = do
start <- getCurrentTime
let ExpensiveHash expected t = expensiveHash tunables
(Salt (KeyId gpgKey ("benchmark" :: B.ByteString)))
("himom" :: B.ByteString)
end <- t `deepseq` getCurrentTime
let diff = floor $ end `diffUTCTime` start
let actual = CPUCost $ Seconds diff
return $ Benchmark
{ expectedBenchmark = expected
, actualBenchmark = actual
}
|
