diff --git a/lib/hx509/hx509.h b/lib/hx509/hx509.h
index 4915905b2..85f084bdb 100644
--- a/lib/hx509/hx509.h
+++ b/lib/hx509/hx509.h
@@ -97,7 +97,8 @@ typedef enum {
 /* flags to hx509_cms_unenvelope */
 #define HX509_CMS_UE_DONT_REQUIRE_KU_ENCIPHERMENT	0x01
 
-/* selectors passed to hx509_select */
+/* selectors passed to hx509_select and hx509_avalible */
+#define HX509_SELECT_ALL 0
 #define HX509_SELECT_DIGEST 1
 #define HX509_SELECT_PUBLIC_SIG 2
 #define HX509_SELECT_PUBLIC_ENC 3