R3721-F3210-F3171-HP High-End Firewalls Attack Protection Configuration Guide-6PW101

NOTE:

FTP command words refer to the command words carried in the FTP requests, including RETR, STOR,

PPE, USER, PASS, PORT, PASV, RNFR, RNTO, DELE, LIST, and QUIT, rather than the command words

typed in the command line. For example, to upload a file named 123.txt, you type command put 123.txt.

In this case, the FTP command word to be filtered is not put but STOR.

• Upload filename filtering—Filters filenames carried in FTP upload requests, preventing clients from

uploading files with the specified names to the server.

• Download filename filtering—Filters filenames carried in FTP download requests, preventing clients

from downloading files with the specified names from the server.

Telnet packet content filtering

Telnet packet content filtering, hereafter referred to as Telnet filtering, filters command words in Telnet

requests, preventing Telnet users from executing specific commands that will greatly impact the normal

operation of the firewall, such as format and reboot.

NOTE:

Telnet command filtering supports the following characters:

• Visible characters—ASCII codes 0x20 to 0x7e.

• Special characters—ASCII codes 0x0, 0x8, 0x0d, 0x0d00, and 0x0d0a.

• Others—Cursor Left (0x1b5b44) and Cursor Right (0x1b5b43).

Configuring content filtering

Configuration guide

To configure content filtering:

1. Configure filtering entries and filtering keywords

You can configure various filtering entries and filtering keywords as needed.

Table 18 Filtering entries and filtering keywords configuration task list

Task Descri

tion

Configuring keyword filtering

entries

Keyword filtering entries include:

• HTTP keyword filtering entries—For header filtering and body filtering in

HTTP filtering policies.

• SMTP keyword filtering entries—For subject filtering, body filtering, and

attachment content filtering in SMTP filtering policies.

• POP3 keyword filtering entries—For subject filtering, body filtering, and

attachment content filtering in POP3 filtering policies.

• FTP keyword filtering entries—For command word filtering in FTP filtering

polices.

• Telnet keyword filtering entries—For command word filtering in Telnet

filtering policies.

By default, no keyword filtering entries exist.