diff --git a/scsh/afs/afs-fs.scm b/scsh/afs/afs-fs.scm
index 9a14d14..e55dc36 100644
--- a/scsh/afs/afs-fs.scm
+++ b/scsh/afs/afs-fs.scm
@@ -60,6 +60,9 @@
 (define all-afs-permissions
   (make-afs-permissions (map char->afs-permission (string->list "rlidwka"))))
 
+(define (afs-permissions<=? p1 p2)
+  (enum-set=? (enum-set-union p1 p2) p2))
+
 ;; access control lists: lists of pairs of user name and
 ;; afs-permissions
 
diff --git a/scsh/afs/interfaces.scm b/scsh/afs/interfaces.scm
index 524ce1a..a9835d5 100644
--- a/scsh/afs/interfaces.scm
+++ b/scsh/afs/interfaces.scm
@@ -2,6 +2,8 @@
   (export
    ((afs-permission afs-permissions) :syntax)
    all-afs-permissions
+   make-afs-permissions
+   afs-permissions<=?
    get-acl
    set-acl!
    add-acl!