diff --git a/src/pkcs11/openssl.c b/src/pkcs11/openssl.c
index 6a68ed8c..7bdb60d2 100644
--- a/src/pkcs11/openssl.c
+++ b/src/pkcs11/openssl.c
@@ -10,6 +10,7 @@
 
 #ifdef HAVE_OPENSSL
 #include <openssl/evp.h>
+#include <openssl/rand.h>
 
 static CK_RV	sc_pkcs11_openssl_md_init(sc_pkcs11_operation_t *);
 static CK_RV	sc_pkcs11_openssl_md_update(sc_pkcs11_operation_t *,