Update hsec-tool to use the new CWE data and validation

Author: TristanCacqueray

code/cwe/src/Security/CWE.hs

@@ -2,7 +2,7 @@
 {-# LANGUAGE DerivingStrategies #-}
 {-# LANGUAGE GeneralizedNewtypeDeriving #-}
 {-# LANGUAGE OverloadedStrings #-}
-module Security.CWE (CWEID, mkCWEID, cweNames, cweIds) where
+module Security.CWE (CWEID, unCWEID, mkCWEID, cweNames, cweIds) where
 
 import Security.CWE.Data
 import Data.Text (Text)
@@ -14,6 +14,10 @@ import Data.Bits
 newtype CWEID = CWEID Word
   deriving newtype (Eq, Ord, Show)
 
+-- | Access the underlying data.
+unCWEID :: CWEID -> Word
+unCWEID (CWEID cwe) = cwe
+
 mkCWEID :: (Integral a, Bits a) => a -> Maybe CWEID
 mkCWEID num = CWEID <$> toIntegralSized num
 

code/hsec-tools/hsec-tools.cabal

@@ -49,6 +49,7 @@ library
     , commonmark            ^>=0.2.2
     , commonmark-pandoc     >=0.2     && <0.3
     , containers            >=0.6     && <0.7
+    , cwe                   >=0.1     && <2
     , directory             <2
     , extra                 ^>=1.7.5
     , filepath              >=1.4     && <1.5

code/hsec-tools/src/Security/Advisories/Definition.hs

@@ -4,14 +4,15 @@ module Security.Advisories.Definition
   ( Advisory(..)
     -- * Supporting types
   , Affected(..)
-  , CWE(..)
+  , CWEID
   , Architecture(..)
   , AffectedVersionRange(..)
   , OS(..)
   , Keyword(..)
   )
   where
 
+import Security.CWE (CWEID)
 import Data.Text (Text)
 import Data.Time (ZonedTime)
 import Distribution.Types.Version (Version)
@@ -26,7 +27,7 @@ data Advisory = Advisory
   { advisoryId :: HsecId
   , advisoryModified :: ZonedTime
   , advisoryPublished :: ZonedTime
-  , advisoryCWEs :: [CWE]
+  , advisoryCWEs :: [CWEID]
   , advisoryKeywords :: [Keyword]
   , advisoryAliases :: [Text]
   , advisoryRelated :: [Text]
@@ -53,9 +54,6 @@ data Affected = Affected
   }
   deriving stock (Show)
 
-newtype CWE = CWE {unCWE :: Integer}
-  deriving stock (Show)
-
 data Architecture
   = AArch64
   | Alpha

code/hsec-tools/src/Security/Advisories/Parse.hs

@@ -14,6 +14,7 @@ module Security.Advisories.Parse
   )
   where
 
+import qualified Security.CWE as CWE
 import Data.Bifunctor (first)
 import Data.Foldable (toList)
 import Data.List (intercalate)
@@ -25,6 +26,7 @@ import GHC.Generics (Generic)
 import qualified Data.Map as Map
 import Data.Sequence (Seq((:<|)))
 import qualified Data.Text as T
+import qualified Data.Text.Read as T
 import qualified Data.Text.Lazy as T (toStrict)
 import Data.Time (ZonedTime(..), LocalTime (LocalTime), midnight, utc)
 import Distribution.Parsec (eitherParsec)
@@ -222,7 +224,7 @@ data AdvisoryMetadata = AdvisoryMetadata
   { amdId         :: HsecId
   , amdModified   :: Maybe ZonedTime
   , amdPublished  :: Maybe ZonedTime
-  , amdCWEs       :: [CWE]
+  , amdCWEs       :: [CWE.CWEID]
   , amdKeywords   :: [Keyword]
   , amdAliases    :: [T.Text]
   , amdRelated    :: [T.Text]
@@ -321,11 +323,26 @@ instance Toml.FromValue HsecId where
 instance Toml.ToValue HsecId where
   toValue = Toml.toValue . printHsecId
 
-instance Toml.FromValue CWE where
-  fromValue v = CWE <$> Toml.fromValue v
-
-instance Toml.ToValue CWE where
-  toValue (CWE x) = Toml.toValue x
+instance Toml.FromValue CWE.CWEID where
+  fromValue v = case v of
+    -- Check if the cwe number is known
+    Toml.Integer int | Just cwe <- CWE.mkCWEID int, Map.member cwe CWE.cweNames -> pure cwe
+    -- Check if the cwe text match "number: description"
+    Toml.String string -> case T.breakOn ":" (T.pack string) of
+      (numTxt, name) -> case T.decimal numTxt of
+        Right (num, "") -> do
+          -- Value is a "num: text", now validate if it's known
+          cwe <- Toml.fromValue (Toml.Integer num)
+          case T.strip (T.drop 1 name) of
+            "" -> pure cwe
+            expectedName -> case Map.lookup cwe CWE.cweNames of
+              Just cweName | expectedName == cweName -> pure cwe
+              _ -> fail ("unexpected description, got: " <> show cwe <> ", expected: " <> show expectedName)
+        _ -> fail ("expected a number, got: " <> show numTxt)
+    _ -> fail "expected a valid number or a cwe text description"
+
+instance Toml.ToValue CWE.CWEID where
+  toValue = Toml.toValue . CWE.unCWEID
 
 instance Toml.FromValue Keyword where
   fromValue v = Keyword <$> Toml.fromValue v