Research On PUF Hardware Security Techniques Based On FPGA

With the separation of design and manufacture in integrated circuit chips,intellectual property owners are heavily suffering from the problem of disclosu re of intellectual property cores.The pirated chips are not only leading to the huge economic losses,but also restricting the development of integrated circuit market.Therefore,researches focused on intellectual property protection techniques are of growing importance in recent years.The hardware security tec hnologies refer to a series of measurements that allow the intellectual property designers to control and observe their designed integrated circuits for protectin g intellectual property right.Physical unclonable function(PUF),which generates unclonable Challenge-Response Pairs and Key using uncontrollable physical properties in the chipmaking process,is one of the hardware security technologies and forms an effective protection for intellectual property cores.During the application of PUF,the key is facing amount of the reliability and security problems due to various factors.Thus,efficient physical unclonable functions are of great significance for the protection of intellectual property.This paper focuses on the research of high reliability and security and low hardware overhead of PUF.The mainly contributions are described as follows:(1)According to the reliability problem of the Ring Oscillator PUF that influenced by environmental factors,we proposed a frequency compensation scheme.This scheme needs to increase the extra sub tractor unit.First,we measure all ring oscillators' frequency at different temperature in FPGA.Secondly,we calculate and record the relationship between frequency and temperature.In this process,Ring Oscillat PUF will be influenced by varied temperature that makes Challenge-Response Pairs cannot output reliable response by themselves.Compared with hardware overhead of 1-out-of-8 schemes,the output reliable response of proposed scheme is 1.66 times longer than the 1-out-of-8 scheme with the same hardware cost.(2)According to the security problems analysis of the Ring Oscillator PUF that influenced by system variation,we designed a method of mean absolu te difference.The Ring Oscillator's frequency of each chips will showed a regular distribution due to system variation(the gradient of thermal annealing,circuit layout).However,the Ring Oscillator's frequency that not obeys random distribution reduces the security of PUF.Firstly,the scheme measures the Ring Oscillator's average frequency of each chips,then filter the corresponding Ring Oscillator's average frequency multiple times to extract true random frequency.Consequently,the output of PUF follows the random distribution.In our experiments,we test the response sequence of PUF oscillator using the NIST random method.Compared with the adjacent coding scheme,the proposed scheme greatly reduced the influence of system variation,and the output response sequence of PUF obeys random distribution.