From ce669863b907839ad1b16a784c0b4077bf59b51e Mon Sep 17 00:00:00 2001 From: Richard van der Hoff <1389908+richvdh@users.noreply.github.com> Date: Wed, 3 Feb 2021 19:45:34 +0000 Subject: [PATCH] Add debug for OIDC flow (#9307) --- changelog.d/9307.misc | 1 + synapse/handlers/oidc_handler.py | 40 ++++++++++++++++++++------------ 2 files changed, 26 insertions(+), 15 deletions(-) create mode 100644 changelog.d/9307.misc diff --git a/changelog.d/9307.misc b/changelog.d/9307.misc new file mode 100644 index 000000000..2f54d1ad0 --- /dev/null +++ b/changelog.d/9307.misc @@ -0,0 +1 @@ +Improve logging for OIDC login flow. diff --git a/synapse/handlers/oidc_handler.py b/synapse/handlers/oidc_handler.py index 71008ec50..3adc75fa4 100644 --- a/synapse/handlers/oidc_handler.py +++ b/synapse/handlers/oidc_handler.py @@ -123,7 +123,6 @@ class OidcHandler: Args: request: the incoming request from the browser. """ - # The provider might redirect with an error. # In that case, just display it as-is. if b"error" in request.args: @@ -137,8 +136,12 @@ class OidcHandler: # either the provider misbehaving or Synapse being misconfigured. # The only exception of that is "access_denied", where the user # probably cancelled the login flow. In other cases, log those errors. - if error != "access_denied": - logger.error("Error from the OIDC provider: %s %s", error, description) + logger.log( + logging.INFO if error == "access_denied" else logging.ERROR, + "Received OIDC callback with error: %s %s", + error, + description, + ) self._sso_handler.render_error(request, error, description) return @@ -149,7 +152,7 @@ class OidcHandler: # Fetch the session cookie session = request.getCookie(SESSION_COOKIE_NAME) # type: Optional[bytes] if session is None: - logger.info("No session cookie found") + logger.info("Received OIDC callback, with no session cookie") self._sso_handler.render_error( request, "missing_session", "No session cookie found" ) @@ -169,7 +172,7 @@ class OidcHandler: # Check for the state query parameter if b"state" not in request.args: - logger.info("State parameter is missing") + logger.info("Received OIDC callback, with no state parameter") self._sso_handler.render_error( request, "invalid_request", "State parameter is missing" ) @@ -183,14 +186,16 @@ class OidcHandler: session, state ) except (MacaroonDeserializationException, ValueError) as e: - logger.exception("Invalid session") + logger.exception("Invalid session for OIDC callback") self._sso_handler.render_error(request, "invalid_session", str(e)) return except MacaroonInvalidSignatureException as e: - logger.exception("Could not verify session") + logger.exception("Could not verify session for OIDC callback") self._sso_handler.render_error(request, "mismatching_session", str(e)) return + logger.info("Received OIDC callback for IdP %s", session_data.idp_id) + oidc_provider = self._providers.get(session_data.idp_id) if not oidc_provider: logger.error("OIDC session uses unknown IdP %r", oidc_provider) @@ -565,6 +570,7 @@ class OidcProvider: Returns: UserInfo: an object representing the user. """ + logger.debug("Using the OAuth2 access_token to request userinfo") metadata = await self.load_metadata() resp = await self._http_client.get_json( @@ -572,6 +578,8 @@ class OidcProvider: headers={"Authorization": ["Bearer {}".format(token["access_token"])]}, ) + logger.debug("Retrieved user info from userinfo endpoint: %r", resp) + return UserInfo(resp) async def _parse_id_token(self, token: Token, nonce: str) -> UserInfo: @@ -600,17 +608,19 @@ class OidcProvider: claims_cls = ImplicitIDToken alg_values = metadata.get("id_token_signing_alg_values_supported", ["RS256"]) - jwt = JsonWebToken(alg_values) claim_options = {"iss": {"values": [metadata["issuer"]]}} + id_token = token["id_token"] + logger.debug("Attempting to decode JWT id_token %r", id_token) + # Try to decode the keys in cache first, then retry by forcing the keys # to be reloaded jwk_set = await self.load_jwks() try: claims = jwt.decode( - token["id_token"], + id_token, key=jwk_set, claims_cls=claims_cls, claims_options=claim_options, @@ -620,13 +630,15 @@ class OidcProvider: logger.info("Reloading JWKS after decode error") jwk_set = await self.load_jwks(force=True) # try reloading the jwks claims = jwt.decode( - token["id_token"], + id_token, key=jwk_set, claims_cls=claims_cls, claims_options=claim_options, claims_params=claims_params, ) + logger.debug("Decoded id_token JWT %r; validating", claims) + claims.validate(leeway=120) # allows 2 min of clock skew return UserInfo(claims) @@ -726,19 +738,18 @@ class OidcProvider: """ # Exchange the code with the provider try: - logger.debug("Exchanging code") + logger.debug("Exchanging OAuth2 code for a token") token = await self._exchange_code(code) except OidcError as e: - logger.exception("Could not exchange code") + logger.exception("Could not exchange OAuth2 code") self._sso_handler.render_error(request, e.error, e.error_description) return - logger.debug("Successfully obtained OAuth2 access token") + logger.debug("Successfully obtained OAuth2 token data: %r", token) # Now that we have a token, get the userinfo, either by decoding the # `id_token` or by fetching the `userinfo_endpoint`. if self._uses_userinfo: - logger.debug("Fetching userinfo") try: userinfo = await self._fetch_userinfo(token) except Exception as e: @@ -746,7 +757,6 @@ class OidcProvider: self._sso_handler.render_error(request, "fetch_error", str(e)) return else: - logger.debug("Extracting userinfo from id_token") try: userinfo = await self._parse_id_token(token, nonce=session_data.nonce) except Exception as e: