--- /dev/null
+#ifndef _AUTHFILE_H
+#define _AUTHFILE_H
+
+int eprint(const char *format, ...); /* must be provided by the caller */
+
+int update_authfile(const char *fn, const char *tokenid, const char *id,
+ const char *password, const char *nonce,
+ const unsigned char *secret, const int secsize,
+ const unsigned char *payload, const int paysize);
+
+#endif