From 478b08bf791d8f84b56a5f0d416dcbb0a7ae5077 Mon Sep 17 00:00:00 2001
From: Gustavo Quadri <87215048+gusquadri@users.noreply.github.com>
Date: Tue, 26 Aug 2025 06:11:58 -0300
Subject: [PATCH] Fix: prevent zero padding in writeRandomPadMax16 causing
 message delivery failures (#1706)

---
 src/Utils/generics.ts | 9 ++-------
 1 file changed, 2 insertions(+), 7 deletions(-)

diff --git a/src/Utils/generics.ts b/src/Utils/generics.ts
index 9da7a21b..13facf88 100644
--- a/src/Utils/generics.ts
+++ b/src/Utils/generics.ts
@@ -70,14 +70,9 @@ export const getKeyAuthor = (key: proto.IMessageKey | undefined | null, meId = '
 
 export const writeRandomPadMax16 = (msg: Uint8Array) => {
 	const pad = randomBytes(1)
+	const padLength = (pad[0]! & 0x0f) + 1
 
-	if (pad[0]) {
-		pad[0] &= 0xf
-	} else {
-		pad[0] = 0xf
-	}
-
-	return Buffer.concat([msg, Buffer.alloc(pad[0], pad[0])])
+	return Buffer.concat([msg, Buffer.alloc(padLength, padLength)])
 }
 
 export const unpadRandomMax16 = (e: Uint8Array | Buffer) => {