Using The Smtp Proxy; Configuring The Smtp Proxy; Setting Access Control Options; Setting Proxy Limits - Watchguard Firebox X20E User Manual

Configuring the SMTP Proxy

Setting access control options

On the Incoming tab, you can set rules that filter IP addresses, network addresses, or host ranges. This
is the same functionality you have in packet filter policies. See Chapter 7, "Firewall Policies" for more
information.
Select the Incoming tab.
1
From the Incoming Filter drop-down list, select Deny, Allow, or No Rule.
2
In the Policy Host field, enter the IP address of the computer that you want to receive the traffic.
3
To use port address translation, enter the new port number in the Port Redirect text box. With
4
port address translation, the destination port in the initial packet header is changed to a different
destination
Select Host IP Address, Network IP Address, or Host Range from the drop-down list to specify
5
IP addresses on the external network that can use this policy. Type the IP address or range of IP
addresses you want to allow and click Add. You can enter more than one address.
Type network IP addresses in "slash" notation.
To have the Firebox save log messages for this policy to the log file, select the Log incoming
6
traffic check box.
Click Submit.
7

Setting proxy limits

On the SMTP Settings tab, you can adjust timeout, email size, and line length limits. This stops the
SMTP proxy from using too many network resources and can prevent some types of attacks. You can
also customize the deny message that users see when an email message is blocked by the SMTP proxy.
Timeout
Set the length of time an incoming SMTP connection can idle before the SMTP proxy closes the
connection.
Maximum email size
By default, the SMTP proxy does not restrict email by size (this field is set to zero). Use this setting
if you want to set the maximum length of incoming SMTP messages. Most email is sent as 7-bit
ASCII text. Encoding can increase the length of files by as much as one-third. To allow messages
120
port as the packet goes through the Edge.
Firebox X Edge e-Series