add cost estimates

1 files changed, 23 insertions, 8 deletions

diff --git a/keysafe.hs b/keysafe.hs
index 7068e22..103388b 100644
--- a/keysafe.hs
+++ b/keysafe.hs
@@ -20,6 +20,8 @@ import Storage
 import Storage.LocalFiles
 import qualified Gpg
 import Data.Maybe
+import Data.Time.Clock
+import Data.Time.Calendar
 import Control.Monad
 import qualified Data.ByteString as B
 import qualified Data.ByteString.UTF8 as BU8
@@ -82,27 +84,36 @@ backup ui tunables secretkeysource secretkey = do
 	name <- fromMaybe (error "Aborting on no name") 
 		<$> promptName ui "Enter name"
 			namedesc username validateName
-	kek <- getkek name
+	kek <- promptkek name
 	let esk = encrypt tunables kek secretkey
 	let sis = shardIdents tunables name secretkeysource
 	shards <- genShards esk tunables
 	print =<< mapM (uncurry (storeShard localFiles)) (zip (getIdents sis) shards)
 	print =<< obscureShards localFiles
   where
-	getkek name = do
+	promptkek name = do
 		password <- fromMaybe (error "Aborting on no password") 
 			<$> promptPassword ui True "Enter password" passworddesc
 		kek <- genKeyEncryptionKey tunables name password
 		username <- userName
 		let badwords = concatMap namewords [name, username]
-		let crackcost = estimateAttack spotAWS $
+		let crackcost = estimateAttackCost spotAWS $
 			estimateBruteforceOf kek $
 				passwordEntropy password badwords
-		ok <- promptQuestion ui "Password strength estimate" $
-			show crackcost
-		if ok
-			then return kek
-			else getkek name
+		let mincost = Dollars 100000
+		if crackcost < mincost
+			then do
+				showError ui $ "Weak password! It would cost less than " ++ show mincost ++ " to crack the password. Please think of a better one. More words would be good.."
+				promptkek name
+			else do
+				(thisyear, _, _) <- toGregorian . utctDay
+					<$> getCurrentTime
+				ok <- promptQuestion ui "Password strength estimate"
+					(crackdesc crackcost thisyear)
+					"Is your password strong enough?"
+				if ok
+					then return kek
+					else promptkek name
 	namewords (Name nb) = words (BU8.toString nb)
 	namedesc = unlines
 		[ "To back up your secret key, you will need to enter a name and a password."
@@ -121,6 +132,10 @@ backup ui tunables secretkeysource secretkey = do
 		, "And, it needs to be one that you will be able to remember years from now"
 		, "in order to restore your secret key."
 		]
+	crackdesc crackcost thisyear = unlines $
+		"Rough estimate of the cost to crack your password: " :
+		map (\(c, y) -> "  " ++ show y ++ ":\t" ++ show c)
+			(costOverTime crackcost thisyear)
 
 restore :: UI -> SecretKeySource -> IO ()
 restore ui secretkeydest = do