Allow disabling Slither (#1327)

This allows explicitly disabling Slither with a new `--disable-slither` command-line flag
or `disableSlither` configuration option. A blinking, red warning will be shown in the UI
when Slither is disabled or otherwise failed, to disuade people from fuzzing without it.

Closes #1318

lib/Echidna/Config.hs

@@ -114,6 +114,7 @@ instance FromJSON EConfigWithUsage where
         <*> v ..:? "balanceContract" ..!= 0
         <*> v ..:? "codeSize"        ..!= 0xffffffff
         <*> v ..:? "prefix"          ..!= "echidna_"
+        <*> v ..:? "disableSlither"  ..!= False
         <*> v ..:? "cryticArgs"      ..!= []
         <*> v ..:? "solcArgs"        ..!= ""
         <*> v ..:? "solcLibs"        ..!= []

lib/Echidna/SourceAnalysis/Slither.hs

@@ -145,8 +145,13 @@ instance FromJSON SlitherInfo where
 
 -- Slither processing
 runSlither :: FilePath -> SolConf -> IO SlitherInfo
-runSlither fp solConf = do
-  findExecutable "slither" >>= \case
+runSlither fp solConf = if solConf.disableSlither
+  then do
+    hPutStrLn stderr $
+        "WARNING: Slither was explicitly disabled. Echidna uses Slither (https://github.com/crytic/slither)"
+        <> " to perform source analysis, which makes fuzzing more effective. You should enable it."
+    pure emptySlitherInfo
+  else findExecutable "slither" >>= \case
     Nothing -> do
       hPutStrLn stderr $
         "WARNING: slither not found. Echidna uses Slither (https://github.com/crytic/slither)"
@@ -177,3 +182,8 @@ runSlither fp solConf = do
 
 emptySlitherInfo :: SlitherInfo
 emptySlitherInfo = SlitherInfo mempty mempty mempty mempty mempty [] [] []
+
+isEmptySlitherInfo :: Maybe SlitherInfo -> Bool
+isEmptySlitherInfo (Just (SlitherInfo _ _ _ _ _ [] [] [])) = True
+isEmptySlitherInfo Nothing = True
+isEmptySlitherInfo _ = False

lib/Echidna/Types/Solidity.hs

@@ -66,6 +66,7 @@ data SolConf = SolConf
   , balanceContract :: Integer          -- ^ Initial balance of contract to test
   , codeSize        :: Integer          -- ^ Max code size for deployed contratcs (default 0xffffffff)
   , prefix          :: Text             -- ^ Function name prefix used to denote tests
+  , disableSlither  :: Bool             -- ^ Whether or not to skip running Slither
   , cryticArgs      :: [String]         -- ^ Args to pass to crytic
   , solcArgs        :: String           -- ^ Args to pass to @solc@
   , solcLibs        :: [String]         -- ^ List of libraries to load, in order.

lib/Echidna/UI.hs

@@ -36,6 +36,7 @@ import Echidna.Campaign (runWorker, spawnListener)
 import Echidna.Output.Corpus (saveCorpusEvent)
 import Echidna.Output.JSON qualified
 import Echidna.Server (runSSEServer)
+import Echidna.SourceAnalysis.Slither (isEmptySlitherInfo)
 import Echidna.Types.Campaign
 import Echidna.Types.Config
 import Echidna.Types.Corpus qualified as Corpus
@@ -126,6 +127,7 @@ ui vm dict initialCorpus cliSelectedContract = do
           , timeStarted = now
           , timeStopped = Nothing
           , now = now
+          , slitherSucceeded = not $ isEmptySlitherInfo env.slitherInfo
           , fetchedContracts = mempty
           , fetchedSlots = mempty
           , fetchedDialog = B.dialog (Just $ str " Fetched contracts/slots ") Nothing 80

lib/Echidna/UI/Widgets.hs

@@ -42,6 +42,7 @@ data UIState = UIState
   , timeStarted :: LocalTime
   , timeStopped :: Maybe LocalTime
   , now :: LocalTime
+  , slitherSucceeded :: Bool
   , fetchedContracts :: Map Addr (Maybe Contract)
   , fetchedSlots :: Map Addr (Map W256 (Maybe W256))
   , fetchedDialog :: B.Dialog () Name
@@ -65,7 +66,8 @@ data UIStateStatus = Uninitialized | Running
 
 attrs :: A.AttrMap
 attrs = A.attrMap (V.white `on` V.black)
-  [ (attrName "failure", fg V.brightRed)
+  [ (attrName "alert", fg V.brightRed `V.withStyle` V.blink `V.withStyle` V.bold)
+  , (attrName "failure", fg V.brightRed)
   , (attrName "maximum", fg V.brightBlue)
   , (attrName "bold", fg V.white `V.withStyle` V.bold)
   , (attrName "tx", fg V.brightWhite)
@@ -79,6 +81,9 @@ attrs = A.attrMap (V.white `on` V.black)
 bold :: Widget n -> Widget n
 bold = withAttr (attrName "bold")
 
+alert :: Widget n -> Widget n
+alert = withAttr (attrName "alert")
+
 failure :: Widget n -> Widget n
 failure = withAttr (attrName "failure")
 
@@ -184,6 +189,8 @@ summaryWidget env uiState =
       str ("Corpus size: " <> show uiState.corpusSize <> " seqs")
       <=>
       str ("New coverage: " <> timeElapsed uiState uiState.lastNewCov <> " ago") <+> fill ' '
+      <=>
+      slitherWidget uiState.slitherSucceeded
   rightSide =
     padLeft (Pad 1)
       (rpcInfoWidget uiState.fetchedContracts uiState.fetchedSlots env.chainId)
@@ -217,6 +224,13 @@ rpcInfoWidget contracts slots chainId =
     let successful = filter isJust fetches
     in outOf (length successful) (length fetches)
 
+slitherWidget
+  :: Bool
+  -> Widget Name
+slitherWidget slitherSucceeded = if slitherSucceeded
+  then success (str "Slither succeeded")
+  else alert (str "No Slither in use!")
+
 outOf :: Int -> Int -> Widget n
 outOf n m =
   let style = if n == m then success else failure

src/Main.hs

@@ -135,6 +135,7 @@ data Options = Options
   , cliDeployer         :: Maybe Addr
   , cliSender           :: [Addr]
   , cliSeed             :: Maybe Int
+  , cliDisableSlither   :: Bool
   , cliCryticArgs       :: Maybe String
   , cliSolcArgs         :: Maybe String
   , cliSymExec          :: Maybe Bool
@@ -210,6 +211,8 @@ options = Options
   <*> optional (option auto $ long "seed"
     <> metavar "SEED"
     <> help "Run with a specific seed.")
+  <*> switch (long "disable-slither"
+    <> help "Disable running Slither.")
   <*> optional (option str $ long "crytic-args"
     <> metavar "ARGS"
     <> help "Additional arguments to use in crytic-compile for the compilation of the contract to test.")
@@ -276,7 +279,8 @@ overrideConfig config Options{..} = do
       }
 
     overrideSolConf solConf = solConf
-      { solcArgs = fromMaybe solConf.solcArgs cliSolcArgs
+      { disableSlither = cliDisableSlither || solConf.disableSlither
+      , solcArgs = fromMaybe solConf.solcArgs cliSolcArgs
       , cryticArgs = maybe solConf.cryticArgs words cliCryticArgs
       , sender = if null cliSender then solConf.sender else Set.fromList cliSender
       , deployer = fromMaybe solConf.deployer cliDeployer

tests/solidity/basic/default.yaml

@@ -40,6 +40,8 @@ balanceAddr: 0xffffffff
 balanceContract: 0
 #codeSize max code size for deployed contratcs (default 0xffffffff)
 codeSize: 0xffffffff
+#whether or not to disable running slither (default false, uses slither)
+disableSlither: false
 #solcArgs allows special args to solc
 solcArgs: ""
 #solcLibs is solc libraries