From f39e25f9720a8ee75fc093df61376dbe46d8c39f Mon Sep 17 00:00:00 2001
From: Jason Volk <jason@zemos.net>
Date: Sun, 12 Feb 2023 18:52:42 -0800
Subject: [PATCH] modules/federation/invite: Re-enable auth fetch attempts for
 non-synapse invites.

ircd::m::vm::fetch: Attempt auth with tolerated failures when opts.auth=false.
---
 matrix/vm_fetch.cc           | 9 +++++++--
 modules/federation/invite.cc | 2 +-
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/matrix/vm_fetch.cc b/matrix/vm_fetch.cc
index e07b050cf..3114c6894 100644
--- a/matrix/vm_fetch.cc
+++ b/matrix/vm_fetch.cc
@@ -327,14 +327,19 @@ catch(const vm::error &e)
 }
 catch(const std::exception &e)
 {
-	log::error
+	log::logf
 	{
-		log, "Fetching auth chain for %s in %s :%s",
+		log, eval.opts->auth? log::ERROR: log::DERROR,
+		"Fetching auth chain for %s in %s :%s",
 		string_view{room.event_id},
 		string_view{room.room_id},
 		e.what(),
 	};
 
+	// Stop propagation if auth not required but fetch attempted anyway
+	if(!eval.opts->auth)
+		return;
+
 	throw;
 }
 
diff --git a/modules/federation/invite.cc b/modules/federation/invite.cc
index f6159ce80..6f0b4ad02 100644
--- a/modules/federation/invite.cc
+++ b/modules/federation/invite.cc
@@ -423,7 +423,7 @@ try
 	vmopts.node_id = request.node_id;
 
 	// Synapse may 403 a fetch of the prev_event of the invite event.
-	vmopts.fetch = false;
+	vmopts.phase.set(m::vm::phase::FETCH_PREV, false);
 
 	// Synapse now 403's a fetch of auth_events of the invite event
 	vmopts.auth = false;