Toward threat estimation of system memory Hardware Trojans John - - PowerPoint PPT Presentation

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UNCLASSIFIED

Toward threat estimation of system memory Hardware Trojans

John Shield, Brad Hopkins, Chris North Redefining R&D Needs for Australian Cyber Security UNSW ACCS at ADFA, November 16th 2015

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The Australian Perspective

• Australia sources all integrated circuits from overseas
• Lack of resources for:

– designing – fabricating – testing chips

• Majority of supply is from non-allied nations

UNCLASSIFIED

Vendor Foundry Location 2014 Revenue 2014 Market Share (%) TSMC Taiwan 25,175 53.7 UMC Taiwan 4,621 9.9 Globalfoundries U.S. 4,400 9.4 Samsung1 South Korea 2,412 5.1 SMIC China 1,970 4.2

Gartner report "Market Share: Semiconductor Foundry, Worldwide, 2014."

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Hardware Trojans

• Modifications to Circuit Boards or Integrated Circuits
• We Focus on Integrated Circuits

– Harder to verify post-production

• Modifications Possible

– Functional – Parametric

• Outcomes

– Leak or Modify Information – Reduce Effectiveness

• Denial of service, degradation of service, integrity attacks, etc.

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Memory Protection

• Memory Protection is Key to Software Security

– Privilege Levels and Data Isolation

MMU Hardware Trojan

Memory Mapping

Software

DRAM Mapping Valid Memory Access Redirected access to blocked region Normal Access DRAM MEMORY CPU HARDWARE Blocked Memory Access

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Memory Trojan – Exemplar Hardware

• Interposer Card
• Redirects memory accesses

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Case Study: Cloud Computing

• Breaking: Memory Isolation between Virtual

Machines

• Description: Data modification of corporate email in

a corporate VM using an public VM

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Case Study: Guest Accounts

• Breaking: Privileged (kernel) Mode and User Mode
• Description: Overwriting a root executable by a guest

user to gain root access

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System Memory Trojan Threat

• Threat Level

– High Threat: Software security hinges on memory protection

• Securing Procurement

– Not viable

• Defence Mechanisms

– None Commercially Available

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Threat Mitigation Strategy

• DST Group – Trustworthy Systems Research

– Research: Trustworthy circuit design using untrusted components – Provides Australian defence context and applications – Collaboration: Integrate external S&T and Industry

• Academia

– Research: Trustworthy software (eg seL4) – Research: Security primitives for hardware & processors

• Industry - Partner early for

– Technology insertion – Transition into capability