Managed DAVx⁵

Managed DAVx⁵ is a version of DAVx⁵ that contains mass-deployment and configuration features for organizations.

Managed configuration

Managed DAVx⁵ allows you to manage DAVx⁵ clients centrally by using these configuration methods (in order of precedence):

  • Android Enterprise (recommended)
  • network configuration: fixed URL (QR code)
  • network configuration: unicast DNS
  • network configuration: Zeroconf (DNS-SD)
  • local configuration file

This configuration is used in the Managed DAVx⁵ UI and for new Managed DAVx⁵ accounts.

Note

Existing Managed DAVx⁵ accounts on your devices won’t be modified when the managed configuration is changed.

Configuration by Android Enterprise

Android Enterprise is the recommended method to configure Managed DAVx⁵. With Android Enterprise, IT departments can deploy apps to managed devices and configure them in a standardized way using MDM software. Apps are configured by managed configurations (sometimes called restrictions) which can be set in the MDM software for every deployed app.

Screenshot of Managed DAVx⁵ configuration over an MDM

You can configure Managed DAVx⁵ using MDM/EMM software.

Network configuration

If Android Enterprise is not an option for you, you can choose between three network configuration methods:

  • fixed URL (entered directly or via QR code)
  • unicast DNS
  • Zeroconf (DNS-SD)

Network configuration requires your Android devices to be connected to the network where the configuration file can be found. Usually, this is a WiFi and/or VPN connection. The following paragraphs apply to all network configuration methods:

Warning

Do not join unsafe WiFi networks when you use network configuration. Other networks might offer other Managed DAVx⁵ configuration files, which could lead to confusion. To avoid this problem, only join well-defined WiFi networks (or use Android Enterprise instead of network configuration).

Certificates

When accessing the configuration file, PKI is used to verify the TLS certificate, so a self-signed certificate won’t work without adding it to the Android device first. We recommend to put the configuration file to a location which is accessible over a trusted certificate. You can then define custom trusted certificates in the configuration file.

Caching

Two types of caching are used to cache Managed DAVx⁵ configuration when it’s taken from the network:

  1. configuration cache and
  2. HTTP cache.
Configuration cache:
Managed DAVx⁵ caches the configuration file which is fetched from the network so that Managed DAVx⁵ configuration is available when there is no network access (and for the time when Managed DAVx⁵ has been started, but the new network configuration is not ready yet). The cache will be overwritten when a new configuration file is downloaded. To reset the cache without a new configuration file, use: Managed DAVx⁵ / About/License / Managed configuration / Reload configuration.
HTTP cache:
The configuration file is cached when it has been downloaded from the network according to the rules of the HTTP protocol. For instance, if the Web server which hosts the configuration file returns a freshness period of one hour, Managed DAVx⁵ will always use the cached version for one hour. However, the configuration file will be downloaded at least once a day (max-age: 1 day) to avoid problems caused by obsolete configuration files. If there is no Expires, the cache will use If-Match and If-Unmodified-Since.

It’s advisable to set an expiration time for the configuration file on the Web server (for instance, one hour) explicitly to avoid unnecessary network traffic every time Managed DAVx⁵ is started on a device.

Configuration by fixed URL

The simplest method to configure Managed DAVx⁵ over the network is to use a fixed configuration file URL, which can for example be provided as a QR code. This method can be used if you don’t want to use automatic discovery of the Managed DAVx⁵ configuration file:

  1. Upload the Managed DAVx⁵ configuration file to a HTTPS server in the network (file name: davdroid-config.json)
  2. Trigger an ACTION_VIEW Intent with the configuration file URL (ending in /davdroid-config.json) to the Android device. To do so, you can
    • scan the QR code of the configuration file URL, then open it with Managed DAVx⁵ (not your browser); or
    • link to the configuration file on some page in your Intranet, and use your browser to open it with Managed DAVx⁵.

To use the QR code method, a QR code scanner app has to be installed first.

You can see and reset the current configuration file URL in Managed DAVx⁵ / About/License / Managed configuration.

Configuration by unicast DNS

Managed DAVx⁵ tries to resolve the SRV and TXT path records of davdroid-configs.local in the local network. In case of success, the resulting URL (https scheme, domain and host taken from SRV, path taken from TXT path, or / else) is used to fetch Managed DAVx⁵ configuration.

An example DNS configuration could look like this:

davdroid-configs.local   IN SRV 1 0 443 internal.example.com
davdroid-configs.local   IN TXT "path=/davdroid/davdroid-config.json"

In this case, Managed DAVx⁵ would try to access the configuration file at https://internal.example.com:443/davdroid/davdroid-config.json.

Configuration by Zeroconf (DNS-SD)

Managed DAVx⁵ can discover a service called davdroid-configs._tcp using DNS-SD. The network configuration file URL (https scheme) will be built from the host and path parts of TXT records (the SRV record is not used because the discovery service is not the same as the referenced configuration). If no host is specified, the host name of the host running the avahi service is used. If no path is specified, / will be used.

You can use any DNS-SD server. If you use avahi, the configuration file could be put into /etc/avahi/services and look like this:

<?xml version="1.0" standalone='no'?>
<!DOCTYPE service-group SYSTEM "avahi-service.dtd">
<service-group>
  <name>Managed DAVx⁵ configuration</name>
  <service protocol="ipv4">
    <type>_davdroid-configs._tcp</type>
    <port>443</port>
    <txt-record>host=internal.example.com</txt-record>
    <txt-record>path=/public/davdroid-config.json</txt-record>
  </service>
</service-group>

In this case, Managed DAVx⁵ would try to download the configuration file from https://internal.example.com/public/davdroid-config.json.

Local configuration file

Managed DAVx⁵ watches the device for a file named davdroid-config.json in the app-private directory (package identifier: com.davdroid.managed) on the external storage, for instance /storage/emulated/0/Android/data/com.davdroid.managed/files/davdroid-config.json.

If no other configuration method is active, you can put a configuration file to this location (using a regular file manager app or adb). Changes in this file will be applied immediately.

This method is only recommended for debugging/testing purposes, for instance if you want to test the configuration file without the influence of potential networking problems.

Warning

Other apps with the external storage permission may read/write the Managed DAVx⁵ configuration file. To avoid this security risk, don’t use the local configuration file method.

Configuration variables

These variables can be used for Managed DAVx⁵ configuration:

Configuration variables
Name Type Description
license text* license data (JSON without surrounding curly brackets)
license_signature text* license signature (Base64)
organization text organization display name; shown in app drawer and login activity
logo_url text (URL) organization logo; shown in login activity; must be publicly accessible without authentication
support_homepage_url text (URL) URL of intranet page with details on how to use Managed DAVx⁵ in this organization and how to get internal support; shown in app drawer
support_email_address text (email address) internal support email address – shown in app drawer and some notifications
support_phone_number text (phone number) internal support phone number – shown in app drawer and some notifications
login_introduction text (simple HTML) message that will be shown when the user adds an account; may contain simple HTML like paragrahps, bold text and links
login_base_url text (URL)* base URL for CalDAV/CardDAV service discovery when an account is added; example: https://server.example.com/dav/
login_user_name text default user name when an account is added – only useful when MDM can pre-fill restrictions from user details
login_certificate_alias text if provided, client certificates will be used for authentication (instead of user name/password); value of this field will be pre-selected (if available)
max_accounts integer maximum number of accounts – no new accounts can be created when this number of accounts is reached
override_proxy boolean* true = system proxy settings are ignored and override_proxy_host and override_proxy_port are used instead; false = system proxy settings are used
override_proxy_host text (host name) HTTP proxy host name
override_proxy_port integer (port number) HTTP proxy port number
wifi_only boolean true = DAVx⁵ will only sync when a WiFi connection is active (doesn’t apply to manually forced synchronization); false = DAVx⁵ will sync regardless of the connection type
wifi_only_ssids text (comma-separated list) when set, DAVx⁵ will only sync when device is connected to one of these WiFis; only used when wifi_only is true; example: wifi1,wifi2,wifi3
contact_group_method text: CATEGORIES or GROUP_VCARDS CATEGORIES = contact groups are stored as per-contact category tags; GROUP_VCARDS = contact groups are separate VCards
manage_calendar_colors boolean true = DAVx⁵ will overwrite local calendar colors with the server colors at every sync; false = DAVx⁵ won’t change local calendar colors at every sync
event_colors boolean true = DAVx⁵ will synchronize event colors; false = DAVx⁵ won’t synchronize event colors; setting to true causes some default calendar apps to crash → make sure that your preferred calendar app is working with this setting

*… required

Configuration file syntax

For the network or local file configuration method, a Managed DAVx⁵ configuration file is required. It contains configuration variables in JSON format, like this:

{
  "license": "<escaped JSON, don't change this>",
  "license_signature": "<don't change this>",
  "organization": "bitfire",
  "logo_url": "https://intranet.example.com/your-logo.png",
  "support_homepage_url": "https://intranet.example.com/how-to-use-davdroid",
  "support_email_address": "it-support@example.com",
  "support_phone_number": "+1 234 56789",
  "login_base_url": "https://caldav+carddav.example.com/",
  "max_accounts": 1,
  "override_proxy": false,
  "wifi_only": true,
  "wifi_only_ssids": "wifi1,wifi2",
  "contact_group_method": "GROUP_VCARDS",
  "manage_calendar_colors": true,
  "event_colors": false
}