diff --git a/src/crypto/openssl.c b/src/crypto/openssl.c
index 2bbf29bc..d5d6cca9 100644
--- a/src/crypto/openssl.c
+++ b/src/crypto/openssl.c
@@ -4,6 +4,7 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 
+#include <stdio.h>
 #include <stdint.h>
 
 #include <openssl/evp.h>
@@ -101,4 +102,4 @@ void osdp_fill_random(uint8_t *buf, int len)
 
 void osdp_crypt_teardown()
 {
-}
\ No newline at end of file
+}