Integrity Through Mediated Interfaces

PI Meeting: Feb 22-23, 2000

Bob Balzer

Information Sciences Institute

balzer@isi.edu

Legend: Changes from previous PI meeting

Technical Objectives

• Wrap Data with Integrity Marks– Insure its Integrity– Record its processing history– Reconstruct it from this history if it is corrupted

• by program bugs

• by malicious attacks

• Demo these capabilities on major COTS product– Microsoft Office Suite (PowerPoint & Word only)– Also demo on a mission critical military system

This Slide Intentionally Blank

Existing Practice

• Integrity Stove-Piped on Tool-by-Tool Basis

• End-to-End Integrity Not Supported

• Persistent Data only Safeguarded by OS

• Corruption Detection is Ad-Hoc

• Corruption Repair– Based on Backups– Not Integrated with Detection

• Wrap Program– Detect access of integrity marked data & decode it

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Mediation Cocoon

Environment = Operating System External Programs

Program

ChangeMonitor

– Monitor User Interface to detect change actions• Translate GUI actions into application specific modifications

Technical Approach

– Detect update of integrity marked data • Re-encode & re-integrity mark the updated data

• Repair any subsequent Corruption from History• Build on existing research infrastructure

Major Risks and Planned Mitigation

• Ability to detect application-level modificationsApplication Openness Spectrum:– Event-Generators: Capture as transaction history– Scripting API: Examine state to infer action– Black-Box: Mediate GUI to infer action=> Generic Mediators + Tool Specific mapping

Two Level ArchitectureM

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Mediation Cocoon

Environment = Operating System External Programs

Program

ChangeMonitor

1. Application Independent GUI Monitor signals action types

2. Application Dependent Change Monitor• Determines Action Parameters

• Logs Modification History

Major Risks and Planned Mitigation

• Ability to detect application-level modificationsApplication Openness Spectrum:– Event-Generators: Capture as transaction history– Scripting API: Examine state to infer action– Black-Box: Mediate GUI to infer action=> Generic Mediators + Tool Specific mapping

• Ability to protect transaction history=> Hide the location of the transaction history

• Virtual File System wrapper• System-level Randomization Techniques

• Tool-Specific Modification Trackers Expensive=> Automate common portions=> Provide rule-based scripting language

Accomplishments To Date

• Corruption Detector (for MS Word 2000)– IDs Document Version on Save (in

Document)– Records Document Cryptographic Digest on Save– Checks Document Cryptographic Digest on Load

• GUI Monitor– Application Independent– Signals types of actions (e.g. buttonclick, typing)

Demo

Demo

• Prototype Change Monitor for MS Word– Determines parameters for application-level action– Records transaction history (for possible Replay)

Accomplishments To DateOther IA Projects

• IFE 2.3 ReRun:

IFE 2.3 ReRun Experiment

• 14 Blue Flags established (asset targets)

• 1 in dispute• 13 captured by Red-Team

– Execution of detected modified executables

IFE 2.3 ReRun Wrapper DefensesDetection

AttacksPrevention

Layered Protection

Tolerance

• Prevent modification of– Database by anyone other than DB Manager– EDI Orders by anyone other than FTP Server – Executables by anyone (during “production”)– Execution of unauthorized processes

• Detect modification of– Executables by checking hidden digital

signature• Tolerate modification of

– Executables by reinstalling hidden saved copy

Accomplishments To DateOther IA Projects

• IFE 2.3 ReRun: only uncaptured blue flag(in dispute)

Demo

• NT Security Manager– Policy specifies

• which processes can run• whether executables should be integrity checked• how processes should be wrapped

– All processes wrapped before execution• New AIA Project :Enterprise Wrappers (ISI/ NAI)

– Goal: Network Management of Host Wrappers Common NT/Linux Interface & Infrastructure

Measures of Success

• Widespread Deployment of Integrity Manager for MS-Office

• Extensibility of Integrity Manager to other COTS products

• Ease of creating Modification Trackers• Resistance to Malicious Attacks

– Corruption Avoidance– Corruption Detection– Corruption Repair=> Red-Team Experiment

Expected Major Achievements

• for Integrity Marked Documents:– End-To-End Data Integrity (through multiple tools/sessions)

– Modifications Monitored, Authorized, & Recorded• Authorization Control of Users, Tools, and Operations • All Changes Attributed and Time Stamped

– Assured Detection of Corruption– Ability to Restore Corrupted Data

• Ability to operate with COTS products• MS-Office Documents Integrity Marked• Mission Critical Military System Integrity Marked

Task Schedule

• Dec99: Tool-Level Integrity Manager– Monitor & Authorize Tool access & updates

• Jun00: Operation-Level Integrity Manager – Monitor, Authorize, & Record Modifications

• Dec00: Integrity Management for MS-Office• Jun01: Corruption Repair• Dec01: Integrity Management for

Mission Critical Military System• Jun02: Automated Modification Tracking

Key Outstanding Issues

• None Yet

Transition of Technology

• Piggyback our Technology on a widely used Target Product (MS Office)– Integrity Manager automatically invoked as needed

• Make technology available for COTS products

• Work with Vendors to encouragepublication of modification events

Needed PM Assistance

• None Yet

Watch this space (Summer PI meeting) Help identifying suitable mission critical military system