Chapter 14 Physical Tamper Resistance Hack a lock:
Physically secure processors Portable tamper resistant IBM 4758 processors rated at governments highest level of security Was found to be breakable see above. Need: To house crypto material is a secure housing
Crypto Processors Attack key entry Attack casing Attack potting material Memory remanence Cold enhances remanence
Classes of attackers Class 1 clever outsiders Class 2 knowledgeable insiders Class 3 funded organizations 4758 aimed at funded organizations
Medium Security Processors iButton Building access Computer access A “what you have” Dallas 5002 Uses bus encryption Clipper chip Encryption with way for government to decrypt all messages
Smart Cards Mobile phones Build “generic phones” Smart card contains user specific data Used by T-mobile Pay-TV subscriber cards, hotel door locks, telephone cards…
Architecture Most 8-bit processor ROM for program and other non changing data EEPROM for customer specific data RAM registers for processing data
Attacks on Smartcards Protocols Slow cards execution Physical tampering DirectTV attacks back
Smartcards Not feasible for total protection Defense in depth Tamper resistance versus tamper evidence Stop loss Recent articles Kinko Fedex cards not SmartCard, but can recharge at Kiosk:
Magnetic stripe Current fraud: _someone.html _someone.html This site has know how for many types of programming:
What goes wrong Architectural errors Protecting the wrong thing Protocol failure Function creep
Discussion articles iButton actual uses What to protect with secure devices (ie 14.8 What should be protected)
Links to material Hardware Hacking chapter: Tamper resistance: Case Study Hack-a-Bike Data remanence
Links to material Tamper resistance evaluation criteria Ibutton Clipper chip
Links to Material Smart Card Security DirectTV fights back Tools