coverity fix 279922 , div by zero

2020-04-28 14:51:47 +02:00
parent ae14272117
commit 7303dd8c5d
1 changed files with 4 additions and 0 deletions
--- a/client/src/mifare/desfire_crypto.c
+++ b/client/src/mifare/desfire_crypto.c
@@ -281,6 +281,10 @@ void cmac_generate_subkeys(desfirekey_t key) {

 void cmac(const desfirekey_t key, uint8_t *ivect, const uint8_t *data, size_t len, uint8_t *cmac) {
    int kbs = key_block_size(key);
+    if (kbs == 0) {
+       return;
+    }
+
    uint8_t *buffer = malloc(padded_data_length(len, kbs));

    memcpy(buffer, data, len);