11.6. Content types

Using filtering by content types, you can block downloads of a specific type of file, such as all *.doc files.

You can subscribe to the content types supplied by UserGate developers. These content type lists are not editable; you can only use them in content filtering rules. To use the lists, an appropriate license is required. For more details on product licensing, see the chapter UserGate Licensing.

To configure filtering by content type, follow these steps:

Task

Description

Step 1. Create a content type list. If UserGate's predefined list is used, skip to Step 3.

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

Step 2. Add the relevant content types to the new list.

Add the relevant content type to the list in the MIME format. A list of content types and their descriptions can be found at this link: https://www.iana.org/assignments/media-types/media-types.xhtml.

For example, to block *.doc documents, add the "application/msword" content type.

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

See the section Content Filtering.

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

Task

Description

Step 1. Create a file with the relevant content types.

Create a file named list.txt with the content type 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 content type list and specify an update URL for it.

On each UserGate server, create a content type 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".