From 7d863bde76a751955b6719aee6cbaa86716a82d7 Mon Sep 17 00:00:00 2001
From: Dakota Brink <779390+codabrink@users.noreply.github.com>
Date: Fri, 20 Dec 2024 17:46:38 -0500
Subject: [PATCH] bring back updating the hmac with the payload (#1445)

---
 xmtp_mls/src/groups/mls_sync.rs | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/xmtp_mls/src/groups/mls_sync.rs b/xmtp_mls/src/groups/mls_sync.rs
index f9bcba57a..522969392 100644
--- a/xmtp_mls/src/groups/mls_sync.rs
+++ b/xmtp_mls/src/groups/mls_sync.rs
@@ -1466,8 +1466,7 @@ where
         let mut result = vec![];
         for payload in payloads {
             let mut sender_hmac = sender_hmac.clone();
-            // When we switch to V2, update with the header bytes.
-            sender_hmac.update(&[]);
+            sender_hmac.update(payload);
             let sender_hmac = sender_hmac.finalize();
 
             result.push(GroupMessageInput {