Checkpoint; not sure where this code is, but I'm rethinking.

tests/rsa/dead/Test.hs

@@ -0,0 +1,73 @@
+import Codec.Crypto.RSA.Pure
+import Control.Monad(forM_)
+import Data.ByteString.Lazy(ByteString)
+import qualified Data.ByteString.Lazy as BS
+import Data.Map.Strict(Map)
+import qualified Data.Map.Strict as Map
+import Numeric
+
+groupBy :: Int -> [a] -> [[a]]
+groupBy _ [] = []
+groupBy x xs =
+  let (first, rest) = splitAt x xs
+  in first : groupBy x rest
+
+dictionary :: [String] -> Map String String
+dictionary [] = Map.empty
+dictionary (x:xs) =
+  let rest = dictionary xs
+      key  = take 1 x
+      val  = drop 3 x
+  in Map.insert key val rest
+
+number :: String -> Integer
+number x =
+  case readHex x of
+    [(v, _)] -> v
+    _        -> error "number"
+
+hash :: String -> (ByteString -> ByteString)
+hash x =
+  case x of
+    "160" -> hashFunction hashSHA1
+    "224" -> hashFunction hashSHA224
+    "256" -> hashFunction hashSHA256
+    "384" -> hashFunction hashSHA384
+    "512" -> hashFunction hashSHA512
+
+decrypter :: String ->
+             (ByteString -> PrivateKey -> ByteString -> Either RSAError ByteString)
+decrypter x = decryptOAEP hashfun (generateMGF1 hashfun)
+  where hashfun = hash x
+
+bytestring :: String -> ByteString
+bytestring "" = BS.empty
+bytestring xs =
+  let (byte1, rest) = splitAt 2 xs
+  in BS.cons (fromIntegral (number byte1)) (bytestring rest)
+
+forceLookup :: String -> Map String String -> String
+forceLookup x m =
+  case Map.lookup x m of
+    Just v  -> v
+    Nothing -> error ("forceLookup: " ++ x)
+
+runCase :: Map String String -> IO ()
+runCase dict =
+  do let d = number (forceLookup "d" dict)
+         n = number (forceLookup "n" dict)
+         m = bytestring (forceLookup "m" dict)
+         s = bytestring (forceLookup "s" dict)
+         c = bytestring (forceLookup "c" dict)
+         public = PublicKey (512 `div` 8) n 65537
+         private = PrivateKey public d 0 0 0 0 0
+         decrypt = decrypter (forceLookup "h" dict)
+     case decrypt BS.empty private m of
+       Left err -> fail ("Error: " ++ show err)
+       Right _  -> putStrLn "OK"
+
+main :: IO ()
+main =
+  do strs <- lines `fmap` readFile "rsa512.test"
+     let groups = groupBy 7 strs
+     forM_ groups (runCase . dictionary)