Abstract
Almost Perfect Nonlinear (APN) functions are very useful in cryptography, when they are used as S-Boxes due to their good resistance to differential cryptanalysis. Also, some of the curves and surfaces defined by the corresponding nonlinear functions have many rational points and have applications to Algebraic-Geometric (AG) codes (Janwa and Wilson in Applied algebra, algebraic algorithms and error-correcting codes (San Juan, PR, 1993), vol 673, pp 180–194, Springer, Berlin, 1993, in IEEE Trans Inform Theory, accepted). An APN function \(f:\mathbb {F}_{2^n}\rightarrow \mathbb {F}_{2^n}\) is called an exceptional APN if it is APN on infinitely many extensions of \(\mathbb {F}_{2^n}\). Aubry et al. (Contemp Math 518:23–31, 2010) conjectured that the only exceptional APN functions are the Gold and the Kasami–Welch monomial functions. They established that a polynomial function of odd degree is not an exceptional APN provided the degree is not a Gold number \((2^k+1)\) or a Kasami–Welch number \((2^{2k}-2^k+1)\). When the degree of the polynomial function is a Gold number, several partial results are known. Here, we prove the relative primeness conjecture of the Gold degree polynomials. This result helps us substantially to make advances toward the resolution of the exceptional APN conjecture in the Gold degree case. We prove that Gold degree polynomials of the form \(x^{2^k+1}+h(x)\), where \(\deg (h)\) is an odd integer, cannot be exceptional APN (with a few natural exceptions). We also prove that the absolutely irreducible components of the Kasami–Welch degree curves intersect transversally at a particular point. Consequently, we prove that Kasami–Welch degree functions of type \(x^{2^{2k}-2^k+1}+h(x)\) produce absolutely irreducible surfaces in the case \(\deg (h) \equiv 3\pmod {4}\); and also \(\deg (h) \equiv 2^{m-1}+1 \pmod {2^m}\) under certain conditions. As a result, we show that the exceptional APN conjecture is true for these classes as well.
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References
Aubry Y., McGuire G., Rodier, F.: A few more functions that are not APN infinitely often. In: Finite Fields: Theory and Applications, Contemp. Math., vol. 518, pp. 23–31. Amer. Math. Soc., Providence, RI (2010).
Beth T., Ding C.: On almost perfect nonlinear permutations. In: Workshop on the Theory and Application of Cryptographic Techniques, pp. 65–76. Springer, Berlin (1993).
Budaghyan L., Carlet C., Leander G.: Constructing new APN functions from known ones. Finite Fields Appl. 15(2), 150–159 (2009).
Carlet C., Charpin P., Zinoviev V.: Codes, bent functions and permutations suitable for DES-like cryptosystems. Des. Codes Cryptogr. 15(2), 125–156 (1998).
Caullery F.: A new large class of functions not APN infinitely often. Des. Codes Cryptogr. 73(2), 601–614 (2014).
Delgado M., Janwa H.: On the Conjecture on APN Functions. (2012). arXiv:1207.5528
Delgado M., Janwa H.: Progress on the Conjecture on APN Functions in Absolutely Irreducible Polynomials, IWSDA2015, December (2015). http://www.slideshare.net/MoisesDelgadoOlorteg/iwsda2015talk16sept2015
Delgado M., Janwa H.: Some new results on the conjecture on APN functions and absolutely irreducible polynomials: the Gold case. Adv. Math. Commun. 11, 389–395 (2017).
Delgado M., Janwa H.: Progress towards the conjecture on APN functions and absolutely irreducible polynomials. (2016). arXiv:1602.02576 [math.NT].
Delgado M., Janwa H.: On the conjecture on APN functions and absolute irreducibility of polynomials. Desig. Codes Cryptogr. 82, 617–627 (2016).
Delgado M., Janwa H.: On the absolute irreducibility of hyperplane sections of generalized Fermat varieties in P3 and the conjecture on exceptional APN functions: the Kasami-Welch degree case. (2016). arXiv:1612.05997 [math.AG].
Delgado M., Janwa H.: Progress towards the conjecture on APN functions and absolutely irreducible polynomials. (2016). arXiv:1602.02576
Delgado M., Janwa H.: On the Completion of the Exceptional APN Conjecture in the Gold degree case and on APN Absolutely Irreducible Polynomials. Congressus Numerantium 229, 135–142 (2017).
Delgado M., Janwa H.: On the Decomposition of Generalized Fermat Varieties in \(P^3\) Corresponding to Kasami-Welch Functions. Congressus Numerantium 232, 101–111 (2020).
Dobbertin H.: Almost perfect nonlinear power functions on \({\rm GF}(2^n)\): the Niho case. Inform. Comput. 151(1–2), 57–72 (1999).
Dobbertin H.: Almost perfect nonlinear power functions on \({\rm GF}(2^n)\): the Welch case. IEEE Trans. Inform. Theory 45(4), 1271–1275 (1999).
Dobbertin H.: Almost perfect nonlinear power functions on GF \((2^n)\): a new case for n divisible by 5. In: Finite Fields and Applications (Augsburg, 1999), pp. 113–121. Springer, Berlin (2001).
Edel Y., Kyureghyan G., Pott A.: A new APN function which is not equivalent to a power mapping. IEEE Trans. Inform. Theory 52(2), 744–747 (2006).
Ferard E.: On the irreducibility of the hyperplane sections of Fermat varieties in \(P^3\) in characteristic 2. Adv. Math. Commun. 8(4), 497–509 (2014).
Ferard E.: A infinite class of Kasami functions that are not APN infinitely often. Arithmet. Geomet. Cryptogr. Coding Theory 686, 45 (2017).
Férard E., Oyono R., Rodier F.: more functions that are not APN infinitely often. The case of Gold and Kasami exponents. In: Arithmetic, Geometry, Cryptography and Coding Theory, Contemp. Math., vol. 574, pp. 27–36. Amer. Math. Soc., Providence, RI (2012). https://doi.org/10.1090/conm/574/11423
Fulton W.: Algebraic curves. Advanced Book Classics. Addison-Wesley Publishing Company Advanced Book Program, Redwood City, CA (An introduction to algebraic geometry, notes written with the collaboration of Richard Weiss, Reprint of 1969 original) (1989).
Ghorpade S.R., Lachaud G.: Number of solutions of equations over finite fields and a conjecture of Lang and Weil. In: Number Theory and Discrete Mathematics, pp. 269–291. Hindustan Book Agency, Gurgaon (2002).
Gold R.: Maximal recursive sequences with 3-valued recursive cross-correlation functions (corresp). IEEE Trans. Inform. Theory 14(1), 154–156 (1968).
Hernando F., McGuire G.: Proof of a conjecture on the sequence of exceptional numbers, classifying cyclic codes and APN functions. J. Algebra 343, 78–92 (2011).
Janwa H., McGuire G., Wilson R.M.: Double-error-correcting cyclic codes and absolutely irreducible polynomials over \({\rm GF}(2)\). J. Algebra 178(2), 665–676 (1995).
Janwa H., Wilson R.M.: Hyperplane sections of Fermat varieties in \(\textbf{ P}^3\) in char. 2 and applications to cyclic codes. In: Applied Algebra, Algebraic Algorithms and Error-correcting Codes (San Juan, PR, 1993). Lecture Notes in Comput. Sci., vol. 673, pp. 180–194. Springer, Berlin (1993).
Janwa H., Wilson R.M.: Rational points on the Klein quartic and the binary cyclic codes \(\langle { {m_1 m_7}}\rangle \). IEEE Trans. Inform. Theory (accepted).
Jedlicka D.: APN monomials over GF \((2^n)\) for infinitely many n. Finite Fields Appl. 13(4), 1006–1028 (2007).
Lang S., Weil A.: Number of points of varieties over finite fields. Am. J. Math. 76, 819–827 (1954).
Lidl R., Niederreiter H.: Finite fields. In: Encyclopedia of Mathematics and its Applications, vol. 20, 2nd edn. Cambridge University Press, Cambridge (1997). (With a foreword by P. M. Cohn).
Lucas E.: Théorie des fonctions numériques simplement périodiques. Am. J. Math. 1, 289–321 (1878).
Nyberg K.: Differentially uniform mappings for cryptography. In: Advances in Cryptology–EUROCRYPT ’93 (Lofthus, 1993). Lecture Notes in Comput. Sci., vol. 765, pp. 55–64. Springer, Berlin (1994). https://doi.org/10.1007/3-540-48285-7-6.
Payne S.E.: A complete determination of translation ovoids in finite desarguian planes. Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti 51(5), 328–331 (1971).
Rodier F.: Borne sur le degré des polynômes presque parfaitement non-linéaires. In: Arithmetic, Geometry, Cryptography and Coding Theory. Contemp. Math., vol. 487, pp. 169–181. Amer. Math. Soc., Providence, RI (2009).
Rodier F.: Functions of degree \(4e\) that are not APN infinitely often. Cryptogr. Commun. 3(4), 227–240 (2011).
Schmidt W.: Equations Over Finite Fields: An Elementary Approach, 2nd edn Kendrick Press, Heber City, UT (2004).
Acknowledgements
We thank the referee for a very thorough reading of the manuscript and for helpful suggestions. Carlos Agrinsoni is supported by the NASA Training Grant No. NNX15AI11H, and 80NSSC20M0052. Opinions, findings, conclusions, or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of NASA. The authors would like to express their thanks to Eric Ferard for helpful observations.
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Delgado, M., Janwa, H. & Agrinsoni, C. Some new techniques and progress towards the resolution of the conjecture of exceptional APN functions and absolutely irreducibility of a class of polynomials. Des. Codes Cryptogr. 91, 2481–2495 (2023). https://doi.org/10.1007/s10623-023-01202-y
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DOI: https://doi.org/10.1007/s10623-023-01202-y
Keywords
- APN functions
- Exceptional APN functions
- Janwa–McGuire–Wilson conjecture
- Absolutely irreducible polynomials
- S-boxes
- Differential cryptanalysis