From 38f102e2e7bc3d472ec0a9bb6d26e365ca8ef530 Mon Sep 17 00:00:00 2001
From: synqa <synqa@socket.moe>
Date: Fri, 30 Jan 2026 14:42:32 +0900
Subject: [PATCH] Fix undefined behavior of left shift

Left shifting UCHAR promotes it to a signed integer. When the
value is >= 128 and shifted by 24, the result sets the sign bit,
causing undefined behavior. Fixes it by explicit casting to UINT.
---
 src/Mayaqua/Encrypt.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Mayaqua/Encrypt.c b/src/Mayaqua/Encrypt.c
index e9b8b745..c52ed16a 100644
--- a/src/Mayaqua/Encrypt.c
+++ b/src/Mayaqua/Encrypt.c
@@ -4761,7 +4761,7 @@ static void MY_SHA0_Transform(MY_SHA0_CTX* ctx) {
 	UCHAR* p = ctx->buf;
 	int t;
 	for(t = 0; t < 16; ++t) {
-		UINT tmp =  *p++ << 24;
+		UINT tmp =  (UINT)*p++ << 24;
 		tmp |= *p++ << 16;
 		tmp |= *p++ << 8;
 		tmp |= *p++;