RAFA: Redundancies-assisted Algebraic Fault Analysis and its implementation on SPN block ciphers

Algebraic Fault Analysis (AFA) is a cryptanalysis for block ciphers proposed by Courtois et al., which incorporates algebraic to overcome the complexity of manual analysis within context Differential (DFA). The effectiveness AFA on lightweight has been demonstrated. However, systems prevents it from attacking heavyweight efficiently. In this paper, we propose novel called Redundancies-assisted (RAFA) facilitate solution in setting ciphers. core idea RAFA expedite SAT solvers modifying systems, accomplished via two methods. first method introduces redundant constraints, time cryptanalysis. second one sophisticated linearization nonlinear Normal Form (ANF). It takes about 9.68 hours attack AES-128. To best our knowledge, work that uses general solver AES with only single injection byte-fault. Moreover, can AES-128 50.92 and 27.54 minutes nibble- bit-based fault model, respectively. comparison, traditional DFA algorithm implemented pure C 4 ~ 5 under all three models investigated work. order show generality RAFA, also apply other results could recover key Serpent-256 SPEEDY-r-192 20.7 1.5 using faults, not break these even when 30 bits 50 their keys are known, Furthermore, no Serpent or SPEEDY known comparable models.