From 3e3dee8a2f8c95afeaafeb76610982b5ea9ada1a Mon Sep 17 00:00:00 2001
From: default <nobody@localhost>
Date: Fri, 15 Dec 2023 21:43:34 +0100
Subject: [PATCH] Avoid propagating Undo messages innecesarily.

---
 activitypub.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/activitypub.c b/activitypub.c
index 80b8a22..5154ecc 100644
--- a/activitypub.c
+++ b/activitypub.c
@@ -468,6 +468,11 @@ int is_msg_for_me(snac *snac, const xs_dict *c_msg)
             return 0;
     }
 
+    /* if it's an Undo, it must be from someone we follow */
+    if (strcmp(type, "Undo") == 0) {
+        return following_check(snac, xs_dict_get(c_msg, "actor"));
+    }
+
     /* if it's not a Create or Update, allow */
     if (!xs_match(type, "Create|Update"))
         return 1;