my_networks= my_hostname= smtpd_helo_required=yes smtpd_client_restrictions smtpd_sender_restrictions smtpd_relay_restrictions smtpd_helo_restrictions smtpd_etrn_restritions smtpd_data_restrictions smtpd_end_of_data_restrictions reject_unknown_client reject_unknown_client_hostname reject_unknown_reverse_client_hostname reject_unknown_helo_hostname reject_unknown_sender_domain reject_non_fqdn_sender reject_non_fqdn_recipient reject_non_fqdn reject_unauth_destination reject_unauth_pipelining check_policy_service permit_my_networks reject_invalid_hostname reject_unknown_hostname reject_non_fqdn_hostname reject_unknown_recpient_domain