extern uschar *tls_certificate; /* Certificate file */
extern uschar *tls_channelbinding_b64; /* string of base64 channel binding */
extern uschar *tls_crl; /* CRL File */
+extern int tls_dh_max_bits; /* don't accept higher lib suggestions */
extern uschar *tls_dhparam; /* DH param file */
#if defined(EXPERIMENTAL_OCSP) && !defined(USE_GNUTLS)
extern uschar *tls_ocsp_file; /* OCSP stapling proof file */