Changeset

5404:1087f697c3f3

mod_http_oauth2: Strip unknown extra fields from client registration We shouldn't sign things we don't understand! RFC 7591 section-2 states: > The authorization server MUST ignore any client metadata sent by the > client that it does not understand (for instance, by silently removing > unknown metadata from the client's registration record during > processing). Prevents grandfathering in of unvalidated data that might become used later, especially since the 'additionalProperties' schema keyword was removed in 698fef74ce53
author Kim Alvefur <zash@zash.se>
date Tue, 02 May 2023 16:23:40 +0200
parents 5403:c574aaaa4d57
children 5405:c7a5caad28ef
files mod_http_oauth2/mod_http_oauth2.lua
diffstat 1 files changed, 6 insertions(+), 2 deletions(-) [+]
line wrap: on
line diff
--- a/mod_http_oauth2/mod_http_oauth2.lua	Tue May 02 16:23:05 2023 +0200
+++ b/mod_http_oauth2/mod_http_oauth2.lua	Tue May 02 16:23:40 2023 +0200
@@ -772,9 +772,13 @@
 		end
 	end
 
-	-- Localized URIs should be secure too
 	for k, v in pairs(client_metadata) do
-		if k:find"_uri#" then
+		local base_k = k:match"^([^#]+)#" or k;
+		if not registration_schema.properties[base_k] or k:find"^client_uri#" then
+			-- Ignore and strip unknown extra properties
+			client_metadata[k] = nil;
+		elseif k:find"_uri#" then
+			-- Localized URIs should be secure too
 			if not redirect_uri_allowed(v, client_uri, "web") then
 				return nil, oauth_error("invalid_client_metadata", "Invalid, insecure or inappropriate informative URI");
 			end