AIR applications that script between application and non-application
content have more complex security arrangements. Files that are
not in the application sandbox are only allowed to access the properties
and methods of files in the application sandbox through the use
of a sandbox bridge. A sandbox bridge acts as a gateway between
application content and non-application content, providing explicit
interaction between the two files. When used correctly, sandbox
bridges provide an extra layer of security, restricting non-application content
from accessing object references that are part of application content.
The benefit of sandbox bridges is best illustrated through example.
Suppose an AIR music store application wants to provide an API to
advertisers who want to create their own SWF files, with which the
store application can then communicate. The store wants to provide
advertisers with methods to look up artists and CDs from the store,
but also wants to isolate some methods and properties from the third-party
SWF file for security reasons.
A sandbox bridge can provide this functionality. By default,
content loaded externally into an AIR application at runtime does
not have access to any methods or properties in the main application.
With a custom sandbox bridge implementation, a developer can provide
services to the remote content without exposing these methods or
properties. Consider the sandbox bridge as a pathway between trusted
and untrusted content, providing communication between loader and
loadee content without exposing object references.
For more information on how to securely use sandbox bridges,
Scripting between content in different domains