A User Centric Security Model for Tamper-Resistant Devices

7.3 UCTD Firewall
utilises CDAM to create a single virtual device comprising heterogeneous devices and
a UCTD-based architecture will enable the ecient replacement of a service if the
host device goes out of the network, by requesting installation of the service on an
alternative available device.
7.3 UCTD Firewall
In this section, we discuss the architecture of the proposed rewall mechanism for UCTDs.
7.3.1 Firewall Architecture
The proposed rewall mechanism is based on the Java Card rewall mechanism as illustrated
in gure 7.3 that is discussed subsequently.
Context A
Context B
Package A
Applet A1
Applet A2
ACL
Application Resource Manager (ARM)
Application
Resource Manager
Java Card Firewall
Application Programming Interface (APIs)
System Classes
Java Card Virtual Machine (JCVM)
Runtime Environment
Smart Card Hardware
Package B
SIO
ACL
Applet B1
Applet B2
Runtime Resource Manager
Entry Point Objects
Native Methods
System Context
ACL: Access Control List. SIO: Shareable Interface Object. ARM: Application Resource Manager
Figure 7.3: Architecture of the UCTD rewall mechanism
The request for an application's shareable resource is handled by the application's Application
Resource Manager (ARM) and the Runtime Resource Manager (RRM) handles the
access to the platform's resources (APIs): see gure 7.3.
The RRM controls the access to the entry point objects that are used to access platform
services. The resource manager will enforce the security policy for applications as dened
by the respective SPs, limiting access to the platform resources as stipulated by the policy.
For each application (package), an Application Resource Manager (ARM) is introduced.
This component will act as the authentication and resource allocation point. A client
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