Require JWT secret, remove default, optionally read from file

Fixes #474, fixes #495 when file is used

main/Main.hs

@@ -12,6 +12,7 @@ import           PostgREST.OpenAPI                    (isMalformedProxyUri)
 import           PostgREST.DbStructure
 
 import           Data.String                          (IsString (..))
+import           Data.Text                            (stripPrefix)
 import           Data.Function                        (id)
 import qualified Hasql.Query                          as H
 import qualified Hasql.Session                        as H
@@ -21,7 +22,6 @@ import qualified Hasql.Pool                           as P
 import           Network.Wai.Handler.Warp
 import           System.IO                            (BufferMode (..),
                                                        hSetBuffering)
-import           Web.JWT                              (secret)
 import           Data.IORef
 #ifndef mingw32_HOST_OS
 import           System.Posix.Signals
@@ -42,7 +42,7 @@ main = do
   hSetBuffering stdin  LineBuffering
   hSetBuffering stderr NoBuffering
 
-  conf <- readOptions
+  conf <- loadSecretFile =<< readOptions
   let host = configHost conf
       port = configPort conf
       proxy = configProxyUri conf
@@ -55,8 +55,6 @@ main = do
   when (isMalformedProxyUri $ toS <$> proxy) $ panic
     "Malformed proxy uri, a correct example: https://example.com:8443/basePath"
 
-  unless (secret "secret" /= configJwtSecret conf) $
-    putStrLn ("WARNING, running in insecure mode, JWT secret is the default value" :: Text)
   putStrLn $ ("Listening on port " :: Text) <> show (configPort conf)
 
   pool <- P.acquire (configPool conf, 10, pgSettings)
@@ -86,3 +84,11 @@ main = do
 #endif
 
   runSettings appSettings $ postgrest conf refDbStructure pool
+
+loadSecretFile :: AppConfig -> IO AppConfig
+loadSecretFile conf = do
+  let s = configJwtSecret conf
+  real <- case stripPrefix "@" s of
+            Nothing -> return s -- the string is the secret, not a filename
+            Just filename -> readFile (toS filename)
+  return conf { configJwtSecret = real }

src/PostgREST/App.hs

@@ -28,6 +28,7 @@ import           Network.HTTP.Types.Status
 import           Network.HTTP.Types.URI    (renderSimpleQuery)
 import           Network.Wai
 import           Network.Wai.Middleware.RequestLogger (logStdout)
+import           Web.JWT                   (secret)
 
 import           Data.Aeson
 import           Data.Aeson.Types          (emptyArray)
@@ -79,7 +80,7 @@ postgrest conf refDbStructure pool =
 
     let schema = toS $ configSchema conf
         apiRequest = userApiRequest schema req body
-        eClaims = jwtClaims (configJwtSecret conf) (iJWT apiRequest) time
+        eClaims = jwtClaims (secret $ configJwtSecret conf) (iJWT apiRequest) time
         authed = containsRole eClaims
         handleReq = runWithClaims conf eClaims (app dbStructure conf) apiRequest
         txMode = transactionMode $ iAction apiRequest
@@ -211,7 +212,7 @@ app dbStructure conf apiRequest =
      Just (PayloadJSON (UniformObjects payload))) -> do
         let p = V.head payload
             singular = iPreferSingular apiRequest
-            jwtSecret = configJwtSecret conf
+            jwtSecret = secret $ configJwtSecret conf
             returnType = lookup (qiName qi) $ dbProcs dbStructure
             returnsJWT = fromMaybe False $
               isInfixOf "jwt_claims" . pdReturnType <$> returnType

src/PostgREST/Config.hs

@@ -31,7 +31,6 @@ import           Options.Applicative
 import           Paths_postgrest             (version)
 import           Protolude hiding            (intercalate)
 import           Safe                        (readMay)
-import           Web.JWT                     (Secret, secret)
 
 -- | Data type to store all command line options
 data AppConfig = AppConfig {
@@ -41,7 +40,7 @@ data AppConfig = AppConfig {
   , configSchema    :: Text
   , configHost      :: Text
   , configPort      :: Int
-  , configJwtSecret :: Secret
+  , configJwtSecret :: Text
   , configPool      :: Int
   , configMaxRows   :: Maybe Integer
   , configQuiet     :: Bool
@@ -55,8 +54,7 @@ argParser = AppConfig
   <*> (toS <$> strOption    (long "schema"     <> short 's' <> help "schema to use for API routes" <> metavar "NAME" <> value "public" <> showDefault))
   <*> (toS <$> strOption    (long "host"       <> short 'l' <> help "hostname or ip on which to run HTTP server" <> metavar "HOST" <> value "*4" <> showDefault))
   <*> option auto  (long "port"       <> short 'p' <> help "port number on which to run HTTP server" <> metavar "PORT" <> value 3000 <> showDefault)
-  <*> (secret . toS <$>
-      strOption    (long "jwt-secret" <> short 'j' <> help "secret used to encrypt and decrypt JWT tokens" <> metavar "SECRET" <> value "secret" <> showDefault))
+  <*> (toS <$> strOption (long "jwt-secret" <> short 'j' <> help "secret used to encrypt and decrypt JWT tokens" <> metavar "SECRET"))
   <*> option auto  (long "pool"       <> short 'o' <> help "max connections in database pool" <> metavar "COUNT" <> value 10 <> showDefault)
   <*> (readMay <$> strOption  (long "max-rows"   <> short 'm' <> help "max rows in response" <> metavar "COUNT" <> value "infinity" <> showDefault))
   <*> pure False

test/SpecHelper.hs

@@ -8,7 +8,6 @@ import Data.CaseInsensitive (CI(..))
 import Text.Regex.TDFA ((=~))
 import qualified Data.ByteString.Char8 as BS
 import System.Process (readProcess)
-import Web.JWT (secret)
 
 import PostgREST.Config (AppConfig(..))
 
@@ -52,19 +51,19 @@ testDbConn = "postgres://postgrest_test_authenticator@localhost:5432/postgrest_t
 
 testCfg :: AppConfig
 testCfg =
-  AppConfig testDbConn "postgrest_test_anonymous" Nothing "test" "localhost" 3000 (secret "safe") 10 Nothing True
+  AppConfig testDbConn "postgrest_test_anonymous" Nothing "test" "localhost" 3000 "safe" 10 Nothing True
 
 testUnicodeCfg :: AppConfig
 testUnicodeCfg =
-  AppConfig testDbConn "postgrest_test_anonymous" Nothing "تست" "localhost" 3000 (secret "safe") 10 Nothing True
+  AppConfig testDbConn "postgrest_test_anonymous" Nothing "تست" "localhost" 3000 "safe" 10 Nothing True
 
 testLtdRowsCfg :: AppConfig
 testLtdRowsCfg =
-  AppConfig testDbConn "postgrest_test_anonymous" Nothing "test" "localhost" 3000 (secret "safe") 10 (Just 2) True
+  AppConfig testDbConn "postgrest_test_anonymous" Nothing "test" "localhost" 3000 "safe" 10 (Just 2) True
 
 testProxyCfg :: AppConfig
 testProxyCfg =
-  AppConfig testDbConn "postgrest_test_anonymous" (Just "https://postgrest.com/openapi.json") "test" "localhost" 3000 (secret "safe") 10 Nothing True
+  AppConfig testDbConn "postgrest_test_anonymous" (Just "https://postgrest.com/openapi.json") "test" "localhost" 3000 "safe" 10 Nothing True
 
 setupDb :: IO ()
 setupDb = do