Web Runtime

The Web Runtime (WRT) engine allows Web applications to run outside the browser. You can install Web applications and use them as standalone applications.

The Web Runtime features include the following:

• Managing Web Applications

  Provides information on supported Web application types and managing Web applications.

• Web Runtime API Support

  Provides information on APIs and features supported by the Web Runtime.

• Web Application Security and Privacy

  Provides information on the key security and privacy considerations for Web applications.

Manage Web applications

The Web Runtime supports the following Web application types:

• Packaged Web applications

• Hosted Web applications

All Web applications must be packaged according to the Widget Packaging and XML Configuration guidelines. However, unlike packaged Web applications, the hosted Web applications have an externally hosted document as their starting page. For more information, see Extending Configuration Elements (in mobile and wearable applications).

You can manage Web applications by:

• Installing Web applications

  To install a Web application, see the guidelines for processing a Web application package. After the installation is completed, the WRT sends a notification of the result.

  The Web Runtime also registers the Web application on the device’s idle screen. It fetches the Web application name and icon from the application package using the rules defined in the Widget Packaging and XML Configuration guidelines.

  If a Web application installation fails due to power failure, the Web Runtime reinstalls it on next boot. The Web Runtime aborts the installation in the following situations:

  • Tizen Web API version supported by the Web Runtime is lower than the minimum version required by the Web application.
  • Web application privilege level is Public, and 1 or more Partner or Platform level API privileges are declared in the configuration file.

Note

A Web application can be installed from the official site for Tizen applications or side-loaded (for example, through a browser or Bluetooth). The <feature> element is ignored in the Tizen Web application installation process.

• Updating Web applications

  The WRT supports updating Web applications when there is a new version available.

  The following rules apply during the Web application updating process:

  • If the Web application that is being updated has a Tizen AppID, it is not updated unless the new version has the exact same Tizen AppID.
  • If the Web application that is being updated has an author signature, it is not updated unless the new version has been signed by the same author.
  • If the Web application that is being updated has no author signature, it is not updated if the new version has an author signature.
  • The updating process is similar to the installation process.
  • Web application data, such as Tizen settings, cookies, and local storage are preserved across updates. You must ensure that the old data in your application is still usable after the update.

• Uninstalling Web applications

  The WRT supports the uninstallation of Web applications. During the uninstallation process, all Web application data, such as preferences, local storage data, cookies, and the local storage folder, are removed.

• Managing Web application life-cycle

  The WRT supports W3C DOM load and unload, and the Page Visibility events for all pages.

  When a Web application is sent to the background or hidden, the JavaScript execution and rendering, including CSS animations, is suspended, unless the application is specifically configured to be a background service.

  When a Web application returns to the foreground, the JavaScript execution and rendering is resumed.

  The Web Runtime supports the following URI schemes: sms://, mmsto://, and mailto://.

  For each supported URI scheme, the Web Runtime launches a registered platform scheme handler with appropriate parameters.

  Content localization is supported according to the Widget Packaging and XML Configuration recommendations.

Web Runtime API support

The main functionality of the Web Runtime is to provide the following Tizen Web APIs to Web applications:

• W3C/HTML5 APIs

• Tizen Device API

It also supports multiple browsing context creation within a single Web application using, for example, the window.open() method, or hyperlink navigation. (The WRT ignores parameters related to the position or size of the window of browsing context.)

Tizen Web APIs can be accessed in the top-level browsing context, such as main document window, and nested browsing contexts, such as iframes.

Note

Tizen Device API can only be used with a locally packaged page. Tizen Device APIs are not available in cross-origin pages.

To access the host page of your Web application, add the domain for access in the config.xml file. For more information, see Content Security Policy.

The Web Runtime also supports the following features:

• Widget Interface.

• maximized and fullscreen view modes of the ‘view-mode’ Media Feature.

Web application security and privacy

The Web application security consists of the following elements:

• Web Application Signature
• Web Application Protection
• Private Storage Support
• HTML5 API Security Policy
• Tizen Device API Security Policy
• Content Security Policy

Web application signature

The Web Runtime follows the XML digital widget signature process:

• Web application can be signed by the author and distributors.
• The first valid Tizen distributor signature, signature1.xml, determines the privilege level of the Web application, which is either Public, Partner, or Platform.
• Web application is installed as a trusted application when it is signed with valid signatures and its privilege level is Public, Partner, or Platform.
• Web application is installed as an untrusted application if it is:
  • Not signed by an author or distributor signature.
  • Signed with a valid signature, but its privilege level is not Public, Partner, or Platform.
• If the signature of a Web application is invalid, it cannot be installed.

Web application protection

For Web applications that explicitly turn on encryption (in mobile and wearable applications) using the <tizen:setting/> element in the configuration file, the Web Runtime provides the following protection features:

• HTML, JavaScript, and CSS files of the Web application stored by the device are encrypted.
• When the Web application is launched, the WRT decrypts all of its resources in a manner which is transparent to the Web application itself.

Private storage support

Each Web application has its own private storage space that is not accessible to any other application.

HTML5 API security policy

The Web applications can use HTML5 APIs, some of which need user permission to execute the API call. For such APIs, the Web Runtime supports specific privileges.

The following table summarizes distributor signature type to API privilege level behavior mapping.

Table: HTML5 API privileges and behavior

Tizen Device API security policy

Web Runtime also provides access to sensitive Device API features after consulting the platform-defined security policy. A Web application or an individual user cannot elevate the permissions set by the platform-defined security policy. The mapping between each Tizen Device API and the corresponding privilege is defined in the API definitions in the Tizen Device API Reference.

The following table summarizes distributor signature type to API privilege level behavior mapping:

Table: Distributor signature type to API privilege level behavior mapping

Content security policy

The Web applications can mitigate various kinds of content injection vulnerabilities, such as cross-site scripting (XSS). The content security policy (CSP) is a declarative policy that lets the author or server administrator of a Web application inform the client from where the application expects to load resources. To mitigate XSS, for example, a Web application can declare from where it expects to load scripts, allowing the client to detect and block malicious scripts injected into the application by an attacker.

Web application configuration can include 1 or more <tizen:content-security-policy>, <tizen:content-security-policy-report-only>, or <tizen:allow-navigation> elements. If these are included, the Web application is set to the CSP-based security mode.

In the CSP-based security mode, the Web Runtime provides content security as per Content Security Policy Level 2 (in mobile applications) and Content Security Policy 1.0 (in wearable applications). CSP policies can be delivered from the following sources:

• Default policy (enforced by WRT, if required): default-src *; script-src 'self'; style-src 'self'; object-src 'none';

• config.xml: <tizen:content-security-policy> or <tizen:content-security-policy-report-only>

  If the CSP is defined in the config.xml file, the configuration-based CSP policy is enforced and the default CSP is ignored.

  If the CSP policy is not defined in the config.xml file, the default CSP policy is enforced.

• HTTP header: Content-Security-Policy or Content-Security-Policy-Report-Only

  If a CSP is present in the HTTP header, the most restrictive policy in the configuration-based CSP and HTTP-based CSP is applied.

Otherwise, the Web application is set to the WARP-based security mode. In this mode, the Web application network and content security is enforced by the legacy <access> tag according to Widget Access Request Policy.

Note

The default CSP enforcement is subject to change in the future.

Note

If a Web application declares the <tizen:allow-navigation> element in its configuration document, the main resource navigation (through the window.open() method or a hyperlink) to an external URL is allowed or restricted accordingly.