#ifndef DISABLE_TLS
extern BOOL gnutls_compat_mode; /* Less security, more compatibility */
extern BOOL gnutls_allow_auto_pkcs11; /* Let GnuTLS autoload PKCS11 modules */
+extern uschar *hosts_require_alpn; /* Mandatory ALPN successful nogitiation */
extern uschar *openssl_options; /* OpenSSL compatibility options */
extern const pcre *regex_STARTTLS; /* For recognizing STARTTLS settings */
+extern uschar *tls_alpn; /* ALPN names acceptable */
extern uschar *tls_certificate; /* Certificate file */
extern uschar *tls_crl; /* CRL File */
extern int tls_dh_max_bits; /* don't accept higher lib suggestions */