11.5. Browser Useragent

With the help of browser useragent filtering, the administrator can block or allow the use of certain browser type by users.

A predefined useragent list is supplied with the product. To configure filtering by useragent type, follow these steps:



Step 1. Generate a useragent list.

In the Categories pane, click Add and give a name to the new useragent list. Optionally, provide a description and update URL for the list.

Step 2. Add the relevant browser useragents to the new list.

In the Patterns pane, add the relevant useragent. A comprehensive list of useragent strings can be found here: http://www.useragentstring.com/pages/useragentstring.php

Step 3. Create a content filtering rule containing one or more lists.

See the section Content Filtering.

The administrator can create custom useragent lists and distribute them centrally to all computers where UserGate is installed. To create such a list, follow these steps:



Step 1. Generate a file with the relevant useragents.

Create a file named list.txt with the useragent list.

Step 2. Create an archive containing this file.

Put the file in a ZIP archive named list.zip.

Step 3. Create a version file for the list.

Create a file named version.txt and specify the list version number inside it, such as 3. On each update of the list, the version number must be incremented.

Step 4. Upload the files to a web server.

Upload the list.zip and version.txt files to your website so that they can be downloaded.

Step 5. Create a useragent list and specify an update URL for it.

On each UserGate server, create a useragent list. When creating the list, select Updatable as the list type and enter the address for downloading updates. UserGate will check for a new version on your website according to the set update download schedule. The schedule can be configured in the list properties. The available options are:

  • Disabled: update checking will not be performed for the selected item.

  • Daily.

  • Weekly.

  • Monthly.

  • Every ... hours.

  • Every ... minutes.

  • Advanced.

With the Advanced option, a crontab-like format is used where the date/time string consists of six space-separated fields. The fields specify the time as follows: (minutes: 0‑59) (hours: 0-23) (days of the month: 1-31) (month: 1-12) (days of the week: 0‑6, where 0 is Sunday). Each of the first five fields can be defined using:

  • An asterisk (*): denotes the entire range (from the first number to the last).

  • A dash (-): denotes a number range. For example, "5-7" means 5, 6, and 7.

  • Lists: comma-separated numbers or ranges. For example, "1,5,10,11" or "1‑11,19‑23".

An asterisk or range spacing: used for spacing out values in ranges. The increment is given after a slash. Examples: "2-10/2" means "2,4,6,8,10" while "*/2" in the "hours" field means "every two hours".