Security evaluation for a class of generalized feistel ciphers

This paper studies the security evaluation against differential and linear attacks for a class of generalized Feistel ciphers. If the round function is bijective and its maximum differential and linear characteristic probabilities are p and q, then the upper bounds of maximum differential and linear characteristic probabilities for 16-round ciphers are p7 and q7. If the round function is bijective and SP structure, the maximum differential and linear characteristic probabilities of S-boxes are pS and qS, the branch number of P is Pd, then the upper bounds of maximum differential and linear characteristic probabilities for 16-round ciphers are (pS)3Pd+1 and (qS)3Pd+1.