Add helper function for generating random MAC addresses

Signed-off-by: Jouni Malinen <j@w1.fi>

src/utils/common.c

@@ -846,3 +846,13 @@ void bin_clear_free(void *bin, size_t len)
 		os_free(bin);
 	}
 }
+
+
+int random_mac_addr(u8 *addr)
+{
+	if (os_get_random(addr, ETH_ALEN) < 0)
+		return -1;
+	addr[0] &= 0xfe; /* unicast */
+	addr[0] |= 0x02; /* locally administered */
+	return 0;
+}

src/utils/common.h

@@ -538,6 +538,8 @@ void int_array_add_unique(int **res, int a);
 void str_clear_free(char *str);
 void bin_clear_free(void *bin, size_t len);
 
+int random_mac_addr(u8 *addr);
+
 
 /*
  * gcc 4.4 ends up generating strict-aliasing warnings about some very common