Enabling Anti-Virus Scanning - D-Link NetDefend DFL-210 User Manual

6.4.6. Anti-Virus Options
To prevent this situation, the adminstrator should specify a Compression Ratio limit. If the limit of
the ration is specified as 10 then this will mean that if the uncompressed file is 10 times larger than
the compressed file, the specified Action should be taken. The Action can be one of:
• Allow - The file is allowed through without virus scanning
• Scan - Scan the file for viruses as normal
• Drop - Drop the file
In all three of the above cases the event is logged.
Example 6.15. Enabling Anti-Virus Scanning
This example shows how to setup an Anti-Virus scanning policy for HTTP traffic from lannet to all-nets We will
assume there is already a NAT rule defined in the IP Rule-set to handle this traffic.
CLI
First, create an HTTP Application Layer Gateway (ALG) Object with Anti-Virus scanning enabled:
gw-world:/> set ALG ALG_HTTP anti_virus Antivirus=Protect
Then, create a Service object using the new HTTP ALG:
gw-world:/> add ServiceTCPUDP http_anti_virus Type=TCP DestinationPorts=80
Finally, modify the NAT rule to use the new service:
gw-world:/> set IPRule NATHttp Service=http_anti_virus
Web Interface
A. First, create an HTTP Application Layer Gateway (ALG) Object:
1. Go to Objects > ALG > Add > HTTP ALG
2. Specify a suitable name for the ALG, for instance anti_virus
3. Click the Antivirus tab
4. Select Protect in the Mode dropdown list
5. Click OK
B. Then, create a Service object using the new HTTP ALG:
1. Go to Local Objects > Services > Add > TCP/UDP service
2. Specify a suitable name for the Service, for instance http_anti_virus
3. Select the TCP in the Type dropdown list
4. Enter 80 in the Destination Port textbox
5. Select the HTTP ALG you just created in the ALG dropdown list
6. Click OK
C. Finally, modify the NAT rule (called NATHttp in this example) to use the new service:
1. Go to Rules > IP Rules
2. In the grid control, click the NAT rule handling the traffic between lannet and all-nets
ALG=anti_virus
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Chapter 6. Security Mechanisms