diff --git a/src/util.h b/src/util.h
index d4bb472..70cf294 100644
--- a/src/util.h
+++ b/src/util.h
@@ -9,6 +9,9 @@
 #ifndef PRIVATE_UTIL_H__
 #define PRIVATE_UTIL_H__
 
+#include <stddef.h>
+#include <stdint.h>
+
 extern void ntlm_memzero(void *data, size_t size);
 extern uint64_t ntlm_htonll(uint64_t value);