Index: crypto/openssh/sk_config.h
===================================================================
--- /dev/null
+++ crypto/openssh/sk_config.h
@@ -0,0 +1 @@
+#define ENABLE_SK_INTERNAL /**/
Index: secure/ssh.mk
===================================================================
--- secure/ssh.mk
+++ secure/ssh.mk
@@ -8,5 +8,6 @@
 SRCS+=	 ssh_namespace.h
 
 .if ${MK_USB} != "no"
-CFLAGS+=	-DENABLE_SK_INTERNAL=1
+# Built-in security key support
+CFLAGS+=	-include sk_config.h
 .endif