From ca983f1473f10f233b4cf8adbd1466ac804f08e9 Mon Sep 17 00:00:00 2001
From: merlokk <807634+merlokk@users.noreply.github.com>
Date: Wed, 7 Jul 2021 18:06:38 +0300
Subject: [PATCH] cmac can be NULL

---
 client/src/mifare/desfirecrypto.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/client/src/mifare/desfirecrypto.c b/client/src/mifare/desfirecrypto.c
index 187744ec7..8960b8b96 100644
--- a/client/src/mifare/desfirecrypto.c
+++ b/client/src/mifare/desfirecrypto.c
@@ -265,6 +265,7 @@ void DesfireCryptoCMAC(DesfireContext *ctx, uint8_t *data, size_t len, uint8_t *
 
     DesfireCryptoEncDec(ctx, true, buffer, len, NULL, true);
 
-    memcpy(cmac, ctx->IV, kbs);
+    if (cmac != NULL)
+        memcpy(cmac, ctx->IV, kbs);
 }