diff --git a/sbin/decryptcore/Makefile b/sbin/decryptcore/Makefile
index 3a3a6a029f8..afaa0311ae5 100644
--- a/sbin/decryptcore/Makefile
+++ b/sbin/decryptcore/Makefile
@@ -2,6 +2,7 @@
 
 PROG=	decryptcore
 
+CFLAGS+=-DOPENSSL_API_COMPAT=0x10100000L
 LIBADD=	crypto pjdlog
 
 MAN=	decryptcore.8