3Com Switch 8800 Family Firewall Module Configuration and Command Reference Guide

Configuring E-mail Filtering 139
Configuring E-mail
Filtering
Configuring E-mail
Address Filtering
E-mail filtering is needed to prevent internal users from sending out unnecessary
information to illegal targets outside intranets. The module enables you to filter
E-mails by their addresses.
Enabling/Disabling E-mail address filtering
Before configuring E-mail address filtering for a firewall, you must enable this
function first for related configurations to take effect.
Perform the following configuration in system view.
E-mail address filtering is disabled by default.
c
CAUTION: You must configure ASPF policies and execute the detect smtp and
detect tcp commands first to enable E-mail address filtering. Refer to section
“Configuring ASPF” “Configuring ASPF” for information about ASPF.
Configuring the default filtering operation
You can configure the default filtering operation for a firewall to make the firewall
to permit/deny packets that do not match the E-mail addresses set by the
administrator.
Perform the following configuration in system view.
Packets that do not match are permitted by default.
Configuring an E-mail address to be filtered
E-mails are filtered according to the address items previously configured in an
E-mail address filtering file. The administrator can manipulate this kind of files to
add or delete E-mail addresses in them, or even clear all the E-mail addresses.
Perform the following configuration in system view.
Tab le 135 Enable E-mail address filtering
Operation Command
Enable E-mail address filtering firewall smtp-filter rcptto enable
Disable E-mail address filtering undo firewall smtp-filter rcptto enable
Tab le 136 Configure the default filtering operation
Operation Command
Configure the default filtering operation
firewall smtp-filter rcptto default { permit
| deny }
Revert to the default filtering operation undo firewall smtp-filter rcptto default