Parameters in /webaccess/

In this section, we will describe all the parameters currently used by the ThinLinc Web Access client. These configuration parameters reside in /opt/thinlinc/etc/conf.d/webaccess.hconf.

/webaccess/cert

The path to the certificate file to be used for TLS encryption.

Note

This certificate may be downloaded by connecting clients to be installed in their browsers. Make sure that this file does not contain a private key.

/webaccess/certkey

The path to the certificate private key file used for TLS encryption.

/webaccess/gnutls_priority

The GnuTLS priority string is used to select the order and availability of TLS versions, ciphers, key exchange, MAC, compression, signature and elliptic curve algorithms for TLS sessions. See GnuTLS priority strings for possible values.

/webaccess/login_page

The URL which is used to redirect back to the Web Access login page on the master server. The default value is /, which redirects to the current server. This parameter needs to be changed when ThinLinc Web Access is used in a cluster setup.

/webaccess/listen_port

The local port for this service to listen on. The default port used is 300.

/webaccess/server_tokens

If set to true, Web Access includes the ThinLinc version, as well as Python version information in the “Server” response header field. If set to false, the “Server” response header will not include any version information. The default value is true.

Note

Disabling server_tokens might make it easier to work with some security scanners that raise alerts when this type of version information is included. But note that hiding version information does nothing to make your server more secure.

/webaccess/trusted_proxies

A space-separated list of proxies that should be considered trusted when handling the X-Forwarded-For HTTP header. Each entry in the list needs to be a valid IP address in either IPv4 or IPv6 format.

For more information on how this feature works and important security implications, see Forwarding client IP addresses.

/webaccess/branding/title

A short string to be displayed in the browser window or tab title. This is empty by default.

The path to the logo to be displayed on the Web Access login page. Any path on the local filesystem works. If this logo used, it will be displayed in place of the ThinLinc logo. A smaller variant of the ThinLinc logo will then appear below the login button.

Maximum displayed width and height is 360 px, it will be scaled down if larger. It is recommended to pick a logo that fits well on a white background. The image formats SVG, PNG, JPEG, GIF, and WEBP are supported. The file must be readable by a non-privileged user. Only the ThinLinc logo is used by default.

/webaccess/branding/background

The path to a background image to be displayed on the Web Access login page. Any path on the local filesystem works. This background will appear only on large screens, surrounding the central box on the login page.

The background image will be stretched to cover the entire page. A semi-transparent white overlay will be applied on top of the background. The image formats SVG, PNG, JPEG, GIF, and WEBP are supported. The file must be readable by a non-privileged user. No background image is used by default.

/webaccess/hsts/policy

Note the warnings about enabling HSTS policy, see Configuring HSTS headers. The results should be considered permanent once enabled and are difficult to reverse. The only way to disable the HSTS policy is to wait for the specified duration, as described below, to pass until visiting the domain again.

  • Off: The default value. The HSTS header will not be sent.

  • Testing: Before setting the policy to permanent, it is recommended to test if the policy works for the intended domains to verify they support HTTPS. This value indicates to the browser that it should only remember this domain for 10 minutes.

  • Permanent: This value indicates that browsers will remember this domain for 2 years. This duration is refreshed every time a domain is revisited, which is why it should be viewed as permanent.

/webaccess/hsts/subdomains_included

The HSTS policy will be applied to the included subdomains of the ThinLinc host if enabled.

Note

It is recommended to verify that all subdomains support HTTPS before enabling this. In order to verify, set policy=testing, restart the service and then visit Web Access in the browser to enable the HSTS policy.

/webaccess/hsts/allow_browser_preload

Requirements: policy=permanent and subdomains_included=true

With allow_browser_preload enabled, it is indicated to the browser that the intention is to add the domain, and subdomains, to the browsers’ lists. This would result in the HSTS policy being enabled at the first visit to the domain or subdomain.

Note

Only use this option if you are sure to support HTTPS for domains and subdomains. It may be difficult to remove domains and subdomains from the preload list.

/webaccess/logging/logfile

The file to use for logging tlwebaccess messages. By default, this is /var/log/tlwebaccess.log.