diff --git a/libexec/ftpd/skey-stuff.c b/libexec/ftpd/skey-stuff.c
new file mode 100644
index 000000000000..fdec650bcef0
--- /dev/null
+++ b/libexec/ftpd/skey-stuff.c
@@ -0,0 +1,23 @@
+/* Author: Wietse Venema, Eindhoven University of Technology. */
+
+#include <stdio.h>
+#include <pwd.h>
+
+#include <skey.h>
+
+/* skey_challenge - additional password prompt stuff */
+
+char   *skey_challenge(name, pwd, pwok)
+char   *name;
+struct passwd *pwd;
+int     pwok;
+{
+    static char buf[128];
+    struct skey skey;
+
+    /* Display s/key challenge where appropriate. */
+
+    if (pwd == 0 || skeychallenge(&skey, pwd->pw_name, buf) != 0)
+	sprintf(buf, "Password required for %s.", name);
+    return (buf);
+}