WDMS 2002 June page 1 Middleware Policies for Intrusion Tolerance QuO Franklin Webber, Partha Pal, Chris Jones, Michael Atighetchi, and Paul Rubel BBN Technologies

WDMS 2002 June page 2 Outline Using middleware for defense against intrusions Defense mechanisms Parameterizing defense policies

WDMS 2002 June page 3 A Distributed Military Application

WDMS 2002 June page 4 A Cyber-Attack

WDMS 2002 June page 5 An Abstract View Attacker Data Processing (Fusion, Analysis, Storage, Forwarding, etc.) Data User Data Source

WDMS 2002 June page 6 Traditional Security Attacker Application Private Resources Private Resources Limited Sharing Trusted OSs and Network

WDMS 2002 June page 7 Most OSs and Networks In Common Use Are Untrustworthy Attacker Application Private Resources Private Resources Limited Sharing OSs and Network

WDMS 2002 June page 8 Cryptographic Techniques Can Block (Most) Direct Access to Application Attacker Application Private Resources Private Resources Limited Sharing OSs and Network CryptoCrypto

WDMS 2002 June page 9 Attacker Raw Resources CPU, bandwidth, files... OSs and NetworkIDSsFirewalls Firewalls Block Some Attacks; Intrusion Detectors Notice Others Application CryptoCrypto

WDMS 2002 June page 10 Application Attacker Raw Resources CPU, bandwidth, files... CryptoCrypto OSs and NetworkIDSsFirewalls Defense-Enabled Application Competes With Attacker for Control of Resources Middleware for QoS and Resource Management

WDMS 2002 June page 11 QuO Adaptive Middleware Technology QuO is BBN-developed middleware that provides: interfaces to property managers, each of which monitors and controls an aspect of the Quality of Service (QoS) offered by an application; specifications of the application’s normal and alternate operating conditions and how QoS should depend on these conditions. QuO has integrated managers for several properties: dependability communication bandwidth real-time processing (using TAO from UC Irvine/WUStL) security (using OODTE access control from NAI) QuO

WDMS 2002 June page 12 QuO adds specification, measurement, and adaptation into the distributed object model Application Developer Mechanism Developer CLIENT Network operation() in args out args + return value IDL STUBS IDL SKELETON OBJECT ADAPTER ORB IIOP ORB IIOP CLIENT OBJECT (SERVANT) OBJECT (SERVANT) OBJ REF CLIENT Delegate Contract SysCond Contract Network MECHANISM/PROPERTY MANAGER operation() in args out args + return value IDL STUBS Delegate SysCond IDL SKELETON OBJECT ADAPTER ORB IIOP ORB IIOP CLIENT OBJECT (SERVANT) OBJECT (SERVANT) OBJ REF Application Developer QuO Developer Mechanism Developer CORBA DOC MODEL QUO/CORBA DOC MODEL

WDMS 2002 June page 13 The QuO Toolkit Supports Building Adaptive Apps or Adding Adaptation to Existing Apps QuO Code Generator QoS Adaptivity Specification CORBA IDL Middleware for QoS and Resource Management

WDMS 2002 June page 14 Implementing Defenses in Middleware for simplicity: QoS concerns separated from functionality of application. Better software engineering. for practicality: Requiring secure, reliable OS and network support is not currently cost-effective. Middleware defenses will augment, not replace, defense mechanisms available in lower system layers. for uniformity: Advanced middleware such as QuO provides a systematic way to integrate defense mechanisms. Middleware can hide peculiarities of different platforms. for reuseability Middleware can support a wide variety of applications.

WDMS 2002 June page 15 Security Domains Limit the Damage From A Single Intrusion hacked domain host router domain host router domain host

WDMS 2002 June page 16 Replication Management Can Replace Killed Processes hacked domain host router domain host router domain host application component replicas QuO replica management

WDMS 2002 June page 17 Bandwidth Management Can Counter Flooding Between Routers hacked domain host router domain host router domain host QuO bandwidth management RSVP reservation or packet-filtered link

WDMS 2002 June page 18 Other Defensive Adaptations Dynamically configure firewalls to block traffic Dynamically configure routers to limit traffic Dynamically change communication ports Dynamically change communication protocols

WDMS 2002 June page 19 Defense Strategy Use QuO middleware to coordinate all available defense mechanisms in a coherent strategy. Our best current strategy has two parts: –“outrun”: move application component replicas off bad hosts and on to good ones –“contain”: quarantine bad hosts and bad LANs by limiting or blocking network traffic from them and, within limits, shutting them down

WDMS 2002 June page 20 Policy Issues for ‘Outrunning’ Where should new replicas be placed? –Always in new security domain? –Always on a new host? –Unpredictably? Should number of replicas change under attack? –Increase for protection against stealth? –Decrease for more rapid response?

WDMS 2002 June page 21 Policy Issues for ‘Containment’ Should quarantine be used? –Or rely only on self-shutdown based on local sensors? When is a domain, LAN, or host judged bad? –Depends on source of warning? –Depends on repeated warnings? –Depends on combination of warnings? Is agreement necessary before quarantine? –Yes: local decisions are easier to spoof –No: global decisions are impeded by flooding

WDMS 2002 June page 22 Avoiding Self-Denial-of-Service How to prevent attacker from spoofing defense into quarantining all security domains? –Limit number or fraction of quarantined domains? –Limit rate of quarantining? –Allow later reintegration of quarantined domains?

WDMS 2002 June page 23 Conclusion The feasibility of adaptive cyber-defense is being explored. Adaptive cyber-defense is naturally implemented in middleware. A strategy for cyber-defense can be parameterized in several ways.