graphql-engine/server/src-lib/Hasura/Server/Auth/JWT.hs
Naveen Naidu 664e9df9c6
Tracing: Simplify HTTP traced request (#5451)
Remove the Inversion of Control (SuspendRequest) and simplify
the tracing of HTTP Requests.

Co-authored-by: Phil Freeman <phil@hasura.io>
2020-07-28 11:51:56 -07:00

493 lines
18 KiB
Haskell

module Hasura.Server.Auth.JWT
( processJwt
, RawJWT
, JWTConfig (..)
, JWTCtx (..)
, Jose.JWKSet (..)
, JWTClaimsFormat (..)
, JwkFetchError (..)
, JWTConfigClaims (..)
, updateJwkRef
, jwkRefreshCtrl
, defaultClaimNs
-- * Exposed for testing
, processJwt_
, allowedRolesClaim
, defaultRoleClaim
) where
import Control.Exception.Lifted (try)
import Control.Lens
import Control.Monad.Trans.Control (MonadBaseControl)
import Control.Monad.Trans.Maybe
import Data.IORef (IORef, readIORef, writeIORef)
import Data.Time.Clock (NominalDiffTime, UTCTime, diffUTCTime,
getCurrentTime)
import GHC.AssertNF
import Network.URI (URI)
import Data.Aeson.Internal (JSONPath)
import Data.Parser.CacheControl
import Data.Parser.Expires
import Hasura.HTTP
import Hasura.Logging (Hasura, LogLevel (..), Logger (..))
import Hasura.Prelude
import Hasura.RQL.Types
import Hasura.Server.Auth.JWT.Internal (parseHmacKey, parseRsaKey)
import Hasura.Server.Auth.JWT.Logging
import Hasura.Server.Utils (executeJSONPath, getRequestHeader,
isSessionVariable, userRoleHeader)
import Hasura.Server.Version (HasVersion)
import Hasura.Session
import qualified Hasura.Tracing as Tracing
import qualified Control.Concurrent.Extended as C
import qualified Crypto.JWT as Jose
import qualified Data.Aeson as J
import qualified Data.Aeson.Casing as J
import qualified Data.Aeson.Internal as J
import qualified Data.Aeson.TH as J
import qualified Data.ByteString.Lazy as BL
import qualified Data.ByteString.Lazy.Char8 as BLC
import qualified Data.CaseInsensitive as CI
import qualified Data.HashMap.Strict as Map
import qualified Data.Parser.JSONPath as JSONPath
import qualified Data.Text as T
import qualified Data.Text.Encoding as T
import qualified Network.HTTP.Client as HTTP
import qualified Network.HTTP.Types as HTTP
import qualified Network.Wreq as Wreq
newtype RawJWT = RawJWT BL.ByteString
data JWTClaimsFormat
= JCFJson
| JCFStringifiedJson
deriving (Show, Eq)
$(J.deriveJSON J.defaultOptions { J.sumEncoding = J.ObjectWithSingleField
, J.constructorTagModifier = J.snakeCase . drop 3 } ''JWTClaimsFormat)
data JWTConfigClaims
= ClaimNsPath JSONPath
| ClaimNs T.Text
deriving (Show, Eq)
instance J.ToJSON JWTConfigClaims where
toJSON (ClaimNsPath nsPath) = J.String . T.pack $ encodeJSONPath nsPath
toJSON (ClaimNs ns) = J.String ns
-- | The JWT configuration we got from the user.
data JWTConfig
= JWTConfig
{ jcKeyOrUrl :: !(Either Jose.JWK URI)
, jcClaimNs :: !JWTConfigClaims
, jcAudience :: !(Maybe Jose.Audience)
, jcClaimsFormat :: !(Maybe JWTClaimsFormat)
, jcIssuer :: !(Maybe Jose.StringOrURI)
} deriving (Show, Eq)
-- | The validated runtime JWT configuration returned by 'mkJwtCtx' in 'setupAuthMode'.
--
-- This is also evidence that the 'jwkRefreshCtrl' thread is running, if an
-- expiration schedule could be determined.
data JWTCtx
= JWTCtx
{ jcxKey :: !(IORef Jose.JWKSet)
-- ^ This needs to be a mutable variable for 'updateJwkRef'.
, jcxClaimNs :: !JWTConfigClaims
, jcxAudience :: !(Maybe Jose.Audience)
, jcxClaimsFormat :: !JWTClaimsFormat
, jcxIssuer :: !(Maybe Jose.StringOrURI)
} deriving (Eq)
instance Show JWTCtx where
show (JWTCtx _ nsM audM cf iss) =
show ["<IORef JWKSet>", show nsM,show audM, show cf, show iss]
data HasuraClaims
= HasuraClaims
{ _cmAllowedRoles :: ![RoleName]
, _cmDefaultRole :: !RoleName
} deriving (Show, Eq)
$(J.deriveJSON (J.aesonDrop 3 J.snakeCase) ''HasuraClaims)
-- NOTE: these must stay lowercase; TODO consider using "Data.CaseInsensitive"
allowedRolesClaim :: T.Text
allowedRolesClaim = "x-hasura-allowed-roles"
defaultRoleClaim :: T.Text
defaultRoleClaim = "x-hasura-default-role"
defaultClaimNs :: T.Text
defaultClaimNs = "https://hasura.io/jwt/claims"
-- | An action that refreshes the JWK at intervals in an infinite loop.
jwkRefreshCtrl
:: (HasVersion, MonadIO m, MonadBaseControl IO m, Tracing.HasReporter m)
=> Logger Hasura
-> HTTP.Manager
-> URI
-> IORef Jose.JWKSet
-> DiffTime
-> m void
jwkRefreshCtrl logger manager url ref time = do
liftIO $ C.sleep time
forever $ Tracing.runTraceT "jwk refresh" do
res <- runExceptT $ updateJwkRef logger manager url ref
mTime <- either (const $ logNotice >> return Nothing) return res
-- if can't parse time from header, defaults to 1 min
-- let delay = maybe (minutes 1) fromUnits mTime
let delay = maybe (minutes 1) (convertDuration) mTime
liftIO $ C.sleep delay
where
logNotice = do
let err = JwkRefreshLog LevelInfo (Just "retrying again in 60 secs") Nothing
liftIO $ unLogger logger err
-- | Given a JWK url, fetch JWK from it and update the IORef
updateJwkRef
:: ( HasVersion
, MonadIO m
, MonadBaseControl IO m
, MonadError JwkFetchError m
, Tracing.MonadTrace m
)
=> Logger Hasura
-> HTTP.Manager
-> URI
-> IORef Jose.JWKSet
-> m (Maybe NominalDiffTime)
updateJwkRef (Logger logger) manager url jwkRef = do
let urlT = T.pack $ show url
infoMsg = "refreshing JWK from endpoint: " <> urlT
liftIO $ logger $ JwkRefreshLog LevelInfo (Just infoMsg) Nothing
res <- try $ do
initReq <- liftIO $ HTTP.parseRequest $ show url
let req = initReq { HTTP.requestHeaders = addDefaultHeaders (HTTP.requestHeaders initReq) }
Tracing.tracedHttpRequest req \req' -> do
liftIO $ HTTP.httpLbs req' manager
resp <- either logAndThrowHttp return res
let status = resp ^. Wreq.responseStatus
respBody = resp ^. Wreq.responseBody
statusCode = status ^. Wreq.statusCode
unless (statusCode >= 200 && statusCode < 300) $ do
let errMsg = "Non-2xx response on fetching JWK from: " <> urlT
err = JFEHttpError url status respBody errMsg
logAndThrow err
let parseErr e = JFEJwkParseError (T.pack e) $ "Error parsing JWK from url: " <> urlT
!jwkset <- either (logAndThrow . parseErr) return $ J.eitherDecode' respBody
liftIO $ do
$assertNFHere jwkset -- so we don't write thunks to mutable vars
writeIORef jwkRef jwkset
-- first check for Cache-Control header to get max-age, if not found, look for Expires header
runMaybeT $ timeFromCacheControl resp <|> timeFromExpires resp
where
parseCacheControlErr e =
JFEExpiryParseError (Just e)
"Failed parsing Cache-Control header from JWK response. Could not find max-age or s-maxage"
parseTimeErr =
JFEExpiryParseError Nothing
"Failed parsing Expires header from JWK response. Value of header is not a valid timestamp"
timeFromCacheControl resp = do
header <- afold $ bsToTxt <$> resp ^? Wreq.responseHeader "Cache-Control"
fromInteger <$> parseMaxAge header `onLeft` \err -> logAndThrowInfo $ parseCacheControlErr $ T.pack err
timeFromExpires resp = do
header <- afold $ bsToTxt <$> resp ^? Wreq.responseHeader "Expires"
expiry <- parseExpirationTime header `onLeft` const (logAndThrowInfo parseTimeErr)
diffUTCTime expiry <$> liftIO getCurrentTime
logAndThrowInfo :: (MonadIO m, MonadError JwkFetchError m) => JwkFetchError -> m a
logAndThrowInfo err = do
liftIO $ logger $ JwkRefreshLog LevelInfo Nothing (Just err)
throwError err
logAndThrow :: (MonadIO m, MonadError JwkFetchError m) => JwkFetchError -> m a
logAndThrow err = do
liftIO $ logger $ JwkRefreshLog (LevelOther "critical") Nothing (Just err)
throwError err
logAndThrowHttp :: (MonadIO m, MonadError JwkFetchError m) => HTTP.HttpException -> m a
logAndThrowHttp httpEx = do
let errMsg = "Error fetching JWK: " <> T.pack (getHttpExceptionMsg httpEx)
err = JFEHttpException (HttpException httpEx) errMsg
logAndThrow err
getHttpExceptionMsg = \case
HTTP.HttpExceptionRequest _ reason -> show reason
HTTP.InvalidUrlException _ reason -> show reason
-- | Process the request headers to verify the JWT and extract UserInfo from it
--
-- Iff no "Authorization" header was passed, we will fall back to the
-- unauthenticated user role [1], if one was configured at server start.
--
-- When no 'x-hasura-user-role' is specified in the request, the mandatory
-- 'x-hasura-default-role' [2] from the JWT claims will be used.
-- [1]: https://hasura.io/docs/1.0/graphql/manual/auth/authentication/unauthenticated-access.html
-- [2]: https://hasura.io/docs/1.0/graphql/manual/auth/authentication/jwt.html#the-spec
processJwt
:: ( MonadIO m
, MonadError QErr m)
=> JWTCtx
-> HTTP.RequestHeaders
-> Maybe RoleName
-> m (UserInfo, Maybe UTCTime)
processJwt = processJwt_ processAuthZHeader
-- Broken out for testing with mocks:
processJwt_
:: (MonadError QErr m)
=> (_JWTCtx -> BLC.ByteString -> m (J.Object, Maybe UTCTime))
-- ^ mock 'processAuthZHeader'
-> _JWTCtx
-> HTTP.RequestHeaders
-> Maybe RoleName
-> m (UserInfo, Maybe UTCTime)
processJwt_ processAuthZHeader_ jwtCtx headers mUnAuthRole =
maybe withoutAuthZHeader withAuthZHeader mAuthZHeader
where
mAuthZHeader = find (\h -> fst h == CI.mk "Authorization") headers
withAuthZHeader (_, authzHeader) = do
(hasuraClaims, expTimeM) <- processAuthZHeader_ jwtCtx $ BL.fromStrict authzHeader
-- filter only x-hasura claims and convert to lower-case
let claimsMap = Map.filterWithKey (\k _ -> isSessionVariable k)
$ Map.fromList $ map (first T.toLower)
$ Map.toList hasuraClaims
HasuraClaims allowedRoles defaultRole <- parseHasuraClaims claimsMap
-- see if there is a x-hasura-role header, or else pick the default role.
-- The role returned is unauthenticated at this point:
let requestedRole = fromMaybe defaultRole $
getRequestHeader userRoleHeader headers >>= mkRoleName . bsToTxt
when (requestedRole `notElem` allowedRoles) $
throw400 AccessDenied "Your requested role is not in allowed roles"
let finalClaims =
Map.delete defaultRoleClaim . Map.delete allowedRolesClaim $ claimsMap
-- transform the map of text:aeson-value -> text:text
metadata <- parseJwtClaim (J.Object finalClaims) "x-hasura-* claims"
userInfo <- mkUserInfo (URBPreDetermined requestedRole) UAdminSecretNotSent $
mkSessionVariablesText $ Map.toList metadata
pure (userInfo, expTimeM)
withoutAuthZHeader = do
unAuthRole <- maybe missingAuthzHeader return mUnAuthRole
userInfo <- mkUserInfo (URBPreDetermined unAuthRole) UAdminSecretNotSent $
mkSessionVariables headers
pure (userInfo, Nothing)
where
missingAuthzHeader =
throw400 InvalidHeaders "Missing Authorization header in JWT authentication mode"
-- Parse and verify the 'Authorization' header, returning the raw claims
-- object, and the expiration, if any.
processAuthZHeader
:: ( MonadIO m
, MonadError QErr m)
=> JWTCtx
-> BLC.ByteString
-> m (J.Object, Maybe UTCTime)
processAuthZHeader jwtCtx@JWTCtx{jcxClaimNs, jcxClaimsFormat} authzHeader = do
-- try to parse JWT token from Authorization header
jwt <- parseAuthzHeader
-- verify the JWT
claims <- liftJWTError invalidJWTError $ verifyJwt jwtCtx $ RawJWT jwt
let expTimeM = fmap (\(Jose.NumericDate t) -> t) $ claims ^. Jose.claimExp
-- see if the hasura claims key exists in the claims map
let mHasuraClaims =
case jcxClaimNs of
ClaimNs k -> Map.lookup k $ claims ^. Jose.unregisteredClaims
ClaimNsPath path -> parseIValueJsonValue $ executeJSONPath path (J.toJSON $ claims ^. Jose.unregisteredClaims)
hasuraClaimsV <- maybe claimsNotFound return mHasuraClaims
-- return hasura claims value as an object. parse from string possibly
(, expTimeM) <$> parseObjectFromString hasuraClaimsV
where
parseAuthzHeader = do
let tokenParts = BLC.words authzHeader
case tokenParts of
["Bearer", jwt] -> return jwt
_ -> malformedAuthzHeader
parseObjectFromString jVal =
case (jcxClaimsFormat, jVal) of
(JCFStringifiedJson, J.String v) ->
either (const $ claimsErr $ strngfyErr v) return
$ J.eitherDecodeStrict $ T.encodeUtf8 v
(JCFStringifiedJson, _) ->
claimsErr "expecting a string when claims_format is stringified_json"
(JCFJson, J.Object o) -> return o
(JCFJson, _) ->
claimsErr "expecting a json object when claims_format is json"
strngfyErr v =
"expecting stringified json at: '"
<> claimsLocation
<> "', but found: " <> v
where
claimsLocation :: Text
claimsLocation =
case jcxClaimNs of
ClaimNsPath path -> T.pack $ "claims_namespace_path " <> encodeJSONPath path
ClaimNs ns -> "claims_namespace " <> ns
claimsErr = throw400 JWTInvalidClaims
parseIValueJsonValue (J.IError _ _) = Nothing
parseIValueJsonValue (J.ISuccess v) = Just v
liftJWTError :: (MonadError e' m) => (e -> e') -> ExceptT e m a -> m a
liftJWTError ef action = do
res <- runExceptT action
either (throwError . ef) return res
invalidJWTError e =
err400 JWTInvalid $ "Could not verify JWT: " <> T.pack (show e)
malformedAuthzHeader =
throw400 InvalidHeaders "Malformed Authorization header"
claimsNotFound = do
let claimsNsError = case jcxClaimNs of
ClaimNsPath path -> T.pack $ "claims not found at claims_namespace_path: '"
<> encodeJSONPath path <> "'"
ClaimNs ns -> "claims key: '" <> ns <> "' not found"
throw400 JWTInvalidClaims claimsNsError
-- parse x-hasura-allowed-roles, x-hasura-default-role from JWT claims
parseHasuraClaims :: forall m. (MonadError QErr m) => J.Object -> m HasuraClaims
parseHasuraClaims claimsMap = do
HasuraClaims <$>
parseClaim allowedRolesClaim "should be a list of roles" <*>
parseClaim defaultRoleClaim "should be a single role name"
where
parseClaim :: J.FromJSON a => Text -> Text -> m a
parseClaim claim hint = do
claimV <- maybe missingClaim return $ Map.lookup claim claimsMap
parseJwtClaim claimV $ "invalid " <> claim <> "; " <> hint
where
missingClaim = throw400 JWTRoleClaimMissing $ "JWT claim does not contain " <> claim
-- | Verify the JWT against given JWK
verifyJwt
:: ( MonadError Jose.JWTError m
, MonadIO m
)
=> JWTCtx
-> RawJWT
-> m Jose.ClaimsSet
verifyJwt ctx (RawJWT rawJWT) = do
key <- liftIO $ readIORef $ jcxKey ctx
jwt <- Jose.decodeCompact rawJWT
t <- liftIO getCurrentTime
Jose.verifyClaimsAt config key t jwt
where
config = case jcxIssuer ctx of
Nothing -> Jose.defaultJWTValidationSettings audCheck
Just iss -> Jose.defaultJWTValidationSettings audCheck
& set Jose.issuerPredicate (== iss)
audCheck audience =
-- dont perform the check if there are no audiences in the conf
case jcxAudience ctx of
Nothing -> True
Just (Jose.Audience audiences) -> audience `elem` audiences
instance J.ToJSON JWTConfig where
toJSON (JWTConfig keyOrUrl claimNs aud claimsFmt iss) =
J.object (jwkFields ++ sharedFields ++ claimsNsFields)
where
jwkFields = case keyOrUrl of
Left _ -> [ "type" J..= J.String "<TYPE REDACTED>"
, "key" J..= J.String "<JWK REDACTED>" ]
Right url -> [ "jwk_url" J..= url ]
claimsNsFields = case claimNs of
ClaimNsPath nsPath ->
["claims_namespace_path" J..= encodeJSONPath nsPath]
ClaimNs ns -> ["claims_namespace" J..= J.String ns]
sharedFields = [ "claims_format" J..= claimsFmt
, "audience" J..= aud
, "issuer" J..= iss
]
-- | Parse from a json string like:
-- | `{"type": "RS256", "key": "<PEM-encoded-public-key-or-X509-cert>"}`
-- | to JWTConfig
instance J.FromJSON JWTConfig where
parseJSON = J.withObject "JWTConfig" $ \o -> do
mRawKey <- o J..:? "key"
claimsNs <- o J..:? "claims_namespace"
claimsNsPath <- o J..:? "claims_namespace_path"
aud <- o J..:? "audience"
iss <- o J..:? "issuer"
jwkUrl <- o J..:? "jwk_url"
isStrngfd <- o J..:? "claims_format"
hasuraClaimsNs <-
case (claimsNsPath,claimsNs) of
(Nothing, Nothing) -> return $ ClaimNs defaultClaimNs
(Just nsPath, Nothing) -> either failJSONPathParsing (return . ClaimNsPath) . JSONPath.parseJSONPath $ nsPath
(Nothing, Just ns) -> return $ ClaimNs ns
(Just _, Just _) -> fail "claims_namespace and claims_namespace_path both cannot be set"
case (mRawKey, jwkUrl) of
(Nothing, Nothing) -> fail "key and jwk_url both cannot be empty"
(Just _, Just _) -> fail "key, jwk_url both cannot be present"
(Just rawKey, Nothing) -> do
keyType <- o J..: "type"
key <- parseKey keyType rawKey
return $ JWTConfig (Left key) hasuraClaimsNs aud isStrngfd iss
(Nothing, Just url) ->
return $ JWTConfig (Right url) hasuraClaimsNs aud isStrngfd iss
where
parseKey keyType rawKey =
case keyType of
"HS256" -> runEither $ parseHmacKey rawKey 256
"HS384" -> runEither $ parseHmacKey rawKey 384
"HS512" -> runEither $ parseHmacKey rawKey 512
"RS256" -> runEither $ parseRsaKey rawKey
"RS384" -> runEither $ parseRsaKey rawKey
"RS512" -> runEither $ parseRsaKey rawKey
-- TODO: support ES256, ES384, ES512, PS256, PS384
_ -> invalidJwk ("Key type: " <> T.unpack keyType <> " is not supported")
runEither = either (invalidJwk . T.unpack) return
invalidJwk msg = fail ("Invalid JWK: " <> msg)
failJSONPathParsing err = fail $ "invalid JSON path claims_namespace_path error: " ++ err
-- Utility:
parseJwtClaim :: (J.FromJSON a, MonadError QErr m) => J.Value -> Text -> m a
parseJwtClaim v errMsg =
case J.fromJSON v of
J.Success val -> return val
J.Error e -> throw400 JWTInvalidClaims $ errMsg <> ": " <> T.pack e