[RSA] remove the need for bytestring in HashDescr and work towards more removal

Crypto/PubKey/HashDescr.hs

@@ -11,8 +11,8 @@
 module Crypto.PubKey.HashDescr
     (
     -- * Types
-      HashFunction
+      HashDescr
-    , HashDescr(..)
+    , runHashDescr
     -- * List of known hash description
     , hashDescrMD2
     , hashDescrMD5
@@ -24,73 +24,20 @@ module Crypto.PubKey.HashDescr
     , hashDescrRIPEMD160
     ) where
 
-import           Data.ByteString.Char8 ()
-import           Data.ByteString (ByteString)
-import qualified Data.ByteString as B
 import           Data.Word
 import           Crypto.Hash
-import qualified Crypto.Internal.ByteArray as B (convert)
+import qualified Crypto.Internal.ByteArray as B
 
--- | A standard hash function returning a digest object
+--
-type HashFunction = ByteString -> ByteString
+-- ** Hack **
-
+--
--- | Describe a hash function and a way to wrap the digest into
+-- this happens to not need a real ASN1 encoder, because
--- an DER encoded ASN1 marshalled structure.
+-- thanks to the digest being a specific size AND
-data HashDescr = HashDescr { hashFunction :: HashFunction             -- ^ hash function
+-- that the digest data is the last bytes in the encoding,
-                           , digestToASN1 :: ByteString -> ByteString -- ^ convertion to an ASN1 wrapped digest bytestring
+-- this allows to just prepend the right prefix to the
-                           }
+-- computed digest, to make it in the expected and valid shape.
-
+--
--- | Describe the MD2 hashing algorithm
+-- Otherwise the expected structure is in the following form:
-hashDescrMD2 :: HashDescr
-hashDescrMD2 =
-    HashDescr { hashFunction = B.convert . (hash :: ByteString -> Digest MD2)
-              , digestToASN1 = toHashWithInfo [0x30,0x20,0x30,0x0c,0x06,0x08,0x2a,0x86,0x48,0x86,0xf7,0x0d,0x02,0x02,0x05,0x00,0x04,0x10]
-              }
--- | Describe the MD5 hashing algorithm
-hashDescrMD5 :: HashDescr
-hashDescrMD5 =
-    HashDescr { hashFunction = B.convert . (hash :: ByteString -> Digest MD5)
-              , digestToASN1 = toHashWithInfo [0x30,0x20,0x30,0x0c,0x06,0x08,0x2a,0x86,0x48,0x86,0xf7,0x0d,0x02,0x05,0x05,0x00,0x04,0x10]
-              }
--- | Describe the SHA1 hashing algorithm
-hashDescrSHA1 :: HashDescr
-hashDescrSHA1 =
-    HashDescr { hashFunction = B.convert . (hash :: ByteString -> Digest SHA1)
-              , digestToASN1 = toHashWithInfo [0x30,0x21,0x30,0x09,0x06,0x05,0x2b,0x0e,0x03,0x02,0x1a,0x05,0x00,0x04,0x14]
-              }
--- | Describe the SHA224 hashing algorithm
-hashDescrSHA224 :: HashDescr
-hashDescrSHA224 =
-    HashDescr { hashFunction = B.convert . (hash :: ByteString -> Digest SHA224)
-              , digestToASN1 = toHashWithInfo [0x30,0x2d,0x30,0x0d,0x06,0x09,0x60,0x86,0x48,0x01,0x65,0x03,0x04,0x02,0x04,0x05,0x00,0x04,0x1c]
-              }
--- | Describe the SHA256 hashing algorithm
-hashDescrSHA256 :: HashDescr
-hashDescrSHA256 =
-    HashDescr { hashFunction = B.convert . (hash :: ByteString -> Digest SHA256)
-              , digestToASN1 = toHashWithInfo [0x30,0x31,0x30,0x0d,0x06,0x09,0x60,0x86,0x48,0x01,0x65,0x03,0x04,0x02,0x01,0x05,0x00,0x04,0x20]
-              }
--- | Describe the SHA384 hashing algorithm
-hashDescrSHA384 :: HashDescr
-hashDescrSHA384 =
-    HashDescr { hashFunction = B.convert . (hash :: ByteString -> Digest SHA384)
-              , digestToASN1 = toHashWithInfo [0x30,0x41,0x30,0x0d,0x06,0x09,0x60,0x86,0x48,0x01,0x65,0x03,0x04,0x02,0x02,0x05,0x00,0x04,0x30]
-              }
--- | Describe the SHA512 hashing algorithm
-hashDescrSHA512 :: HashDescr
-hashDescrSHA512 =
-    HashDescr { hashFunction = B.convert . (hash :: ByteString -> Digest SHA512)
-              , digestToASN1 = toHashWithInfo [0x30,0x51,0x30,0x0d,0x06,0x09,0x60,0x86,0x48,0x01,0x65,0x03,0x04,0x02,0x03,0x05,0x00,0x04,0x40]
-              }
-
--- | Describe the RIPEMD160 hashing algorithm
-hashDescrRIPEMD160 :: HashDescr
-hashDescrRIPEMD160 =
-    HashDescr { hashFunction = B.convert . (hash :: ByteString -> Digest RIPEMD160)
-              , digestToASN1 = toHashWithInfo [0x30,0x21,0x30,0x09,0x06,0x05,0x2b,0x24,0x03,0x02,0x01,0x05,0x00,0x04,0x14]
-              }
-
--- | Generate the marshalled structure with the following ASN1 structure:
 --
 --   Start Sequence
 --     ,Start Sequence
@@ -99,6 +46,57 @@ hashDescrRIPEMD160 =
 --     ,End Sequence
 --     ,OctetString digest
 --   ,End Sequence
---
+
-toHashWithInfo :: [Word8] -> ByteString -> ByteString
+hashDescr :: (B.ByteArray ba, HashAlgorithm hashAlg)
-toHashWithInfo pre digest = B.pack pre `B.append` digest
+          => hashAlg -- ^ hash algorithm to use
+          -> [Word8] -- ^ the raw DER encoded ASN1 description of hash algorithm followed by the digest to be filled
+          -> HashDescr hashAlg ba
+hashDescr hashAlg preASN1Descr =
+    HashDescr (\input -> B.pack preASN1Descr `B.append` B.convert (hashWith hashAlg input))
+
+-- | A hash methods to generate a ASN.1 structure digest
+data HashDescr hashAlg ba = HashDescr { unHashDescr :: ba -> ba }
+
+-- | Run the digest function on some input and get the raw bytes
+runHashDescr :: (HashAlgorithm hashAlg, B.ByteArray ba) => HashDescr hashAlg ba -> ba -> ba
+runHashDescr h = unHashDescr h
+
+-- | Describe the MD2 hashing algorithm
+hashDescrMD2 :: B.ByteArray ba => HashDescr MD2 ba
+hashDescrMD2 =
+    hashDescr MD2 [0x30,0x20,0x30,0x0c,0x06,0x08,0x2a,0x86,0x48,0x86,0xf7,0x0d,0x02,0x02,0x05,0x00,0x04,0x10]
+
+-- | Describe the MD5 hashing algorithm
+hashDescrMD5 :: B.ByteArray ba => HashDescr MD5 ba
+hashDescrMD5 =
+    hashDescr MD5 [0x30,0x20,0x30,0x0c,0x06,0x08,0x2a,0x86,0x48,0x86,0xf7,0x0d,0x02,0x05,0x05,0x00,0x04,0x10]
+
+-- | Describe the SHA1 hashing algorithm
+hashDescrSHA1 :: B.ByteArray ba => HashDescr SHA1 ba
+hashDescrSHA1 =
+    hashDescr SHA1 [0x30,0x21,0x30,0x09,0x06,0x05,0x2b,0x0e,0x03,0x02,0x1a,0x05,0x00,0x04,0x14]
+
+-- | Describe the SHA224 hashing algorithm
+hashDescrSHA224 :: B.ByteArray ba => HashDescr SHA224 ba
+hashDescrSHA224 =
+    hashDescr SHA224 [0x30,0x2d,0x30,0x0d,0x06,0x09,0x60,0x86,0x48,0x01,0x65,0x03,0x04,0x02,0x04,0x05,0x00,0x04,0x1c]
+
+-- | Describe the SHA256 hashing algorithm
+hashDescrSHA256 :: B.ByteArray ba => HashDescr SHA256 ba
+hashDescrSHA256 =
+    hashDescr SHA256 [0x30,0x31,0x30,0x0d,0x06,0x09,0x60,0x86,0x48,0x01,0x65,0x03,0x04,0x02,0x01,0x05,0x00,0x04,0x20]
+
+-- | Describe the SHA384 hashing algorithm
+hashDescrSHA384 :: B.ByteArray ba => HashDescr SHA384 ba
+hashDescrSHA384 =
+    hashDescr SHA384 [0x30,0x41,0x30,0x0d,0x06,0x09,0x60,0x86,0x48,0x01,0x65,0x03,0x04,0x02,0x02,0x05,0x00,0x04,0x30]
+
+-- | Describe the SHA512 hashing algorithm
+hashDescrSHA512 :: B.ByteArray ba => HashDescr SHA512 ba
+hashDescrSHA512 =
+    hashDescr SHA512 [0x30,0x51,0x30,0x0d,0x06,0x09,0x60,0x86,0x48,0x01,0x65,0x03,0x04,0x02,0x03,0x05,0x00,0x04,0x40]
+
+-- | Describe the RIPEMD160 hashing algorithm
+hashDescrRIPEMD160 :: B.ByteArray ba => HashDescr RIPEMD160 ba
+hashDescrRIPEMD160 =
+    hashDescr RIPEMD160 [0x30,0x21,0x30,0x09,0x06,0x05,0x2b,0x24,0x03,0x02,0x01,0x05,0x00,0x04,0x14]

Crypto/PubKey/RSA/PKCS15.hs

@@ -27,6 +27,7 @@ import           Crypto.PubKey.RSA.Types
 import           Crypto.PubKey.RSA.Prim
 import           Crypto.PubKey.RSA (generateBlinder)
 import           Crypto.PubKey.HashDescr
+import           Crypto.Hash (HashAlgorithm)
 
 import           Data.ByteString (ByteString)
 
@@ -115,16 +116,17 @@ encrypt pk m = do
 -- information from the timing of the operation, the blinder can be set to None.
 --
 -- If unsure always set a blinder or use signSafer
-sign :: Maybe Blinder -- ^ optional blinder
+sign :: HashAlgorithm hashAlg
-     -> HashDescr     -- ^ hash descriptor
+     => Maybe Blinder -- ^ optional blinder
+     -> HashDescr hashAlg ByteString -- ^ hash descriptor
      -> PrivateKey    -- ^ private key
      -> ByteString    -- ^ message to sign
      -> Either Error ByteString
 sign blinder hashDescr pk m = dp blinder pk `fmap` makeSignature hashDescr (private_size pk) m
 
 -- | sign message using the private key and by automatically generating a blinder.
-signSafer :: MonadRandom m
+signSafer :: (HashAlgorithm hashAlg, MonadRandom m)
-          => HashDescr  -- ^ Hash descriptor
+          => HashDescr hashAlg ByteString -- ^ Hash descriptor
           -> PrivateKey -- ^ private key
           -> ByteString -- ^ message to sign
           -> m (Either Error ByteString)
@@ -133,13 +135,21 @@ signSafer hashDescr pk m = do
     return (sign (Just blinder) hashDescr pk m)
 
 -- | verify message with the signed message
-verify :: HashDescr -> PublicKey -> ByteString -> ByteString -> Bool
+verify :: HashAlgorithm hashAlg
+       => HashDescr hashAlg ByteString
+       -> PublicKey
+       -> ByteString
+       -> ByteString
+       -> Bool
 verify hashDescr pk m sm =
     case makeSignature hashDescr (public_size pk) m of
         Left _  -> False
         Right s -> s == (ep pk sm)
 
-{- makeSignature for sign and verify -}
+-- | make signature digest, used in 'sign' and 'verify'
-makeSignature :: HashDescr -> Int -> ByteString -> Either Error ByteString
+makeSignature :: HashAlgorithm hashAlg
-makeSignature hashDescr klen m = padSignature klen signature
+              => HashDescr hashAlg ByteString
-    where signature = (digestToASN1 hashDescr) $ (hashFunction hashDescr) m
+              -> Int
+              -> ByteString
+              -> Either Error ByteString
+makeSignature hashDescr klen m = padSignature klen (runHashDescr hashDescr m)