51 research outputs found
Efficient Unified Arithmetic for Hardware Cryptography
The basic arithmetic operations (i.e. addition, multiplication, and inversion) in finite fields, GF(q), where q = pk and p is a prime integer, have several applications in cryptography, such as RSA algorithm, Diffie-Hellman key exchange algorithm [1], the US federal Digital Signature Standard [2], elliptic curve cryptography [3, 4], and also recently identity based cryptography [5, 6]. Most popular finite fields that are heavily used in cryptographic applications due to elliptic curve based schemes are prime fields GF(p) and binary extension fields GF(2n). Recently, identity based cryptography based on pairing operations defined over elliptic curve points has stimulated a significant level of interest in the arithmetic of ternary extension fields, GF(3^n)
A New Algorithm for Inversion mod
A new algorithm for computing is introduced.
It is based on the exact solution of linear equations using
-adic expansions. It starts with the initial value
and iteratively computes the digits of
the inverse in base .
The mod 2 version of the algorithm is significantly more
efficient than the existing algorithms for small values
of . We also describe and analyze
all existing algorithms, and compare them to
the proposed algorithm.
Our algorithm stands out as being the only one that works
for any , any , and digit-by-digit. Moreover it requires
the minimal number of arithmetic operations (just a single
addition) per step
Development of Cryptography since Shannon
This paper presents the development of cryptography since Shannon\u27s seminal paper ``Communication Theory of Secrecy Systems\u27\u27 in 1949
A Matrix Decomposition Method for Optimal Normal Basis Multiplication
We introduce a matrix decomposition method and prove that multiplication in GF(2^k) with a Type 1 optimal normal basis for can be performed using k^2-1 XOR gates irrespective of the choice of the irreducible polynomial generating the field. The previous results achieved this bound only with special irreducible polynomials. Furthermore, the decomposition method performs the multiplication operation using 1.5k(k-1) XOR gates for Type 2a and 2b optimal normal bases, which matches previous bounds
Improved Plantard Arithmetic for Lattice-based Cryptography
This paper presents an improved Plantard’s modular arithmetic (Plantard arithmetic) tailored for Lattice-Based Cryptography (LBC). Based on the improved Plantard arithmetic, we present faster implementations of two LBC schemes, Kyber and NTTRU, running on Cortex-M4. The intrinsic advantage of Plantard arithmetic is that one multiplication can be saved from the modular multiplication of a constant. However, the original Plantard arithmetic is not very practical in LBC schemes because of the limitation on the unsigned input range. In this paper, we improve the Plantard arithmetic and customize it for the existing LBC schemes with theoretical proof. The improved Plantard arithmetic not only inherits its aforementioned advantage but also accepts signed inputs, produces signed output, and enlarges its input range compared with the original design. Moreover, compared with the state-of-the-art Montgomery arithmetic, the improved Plantard arithmetic has a larger input range and smaller output range, which allows better lazy reduction strategies during the NTT/INTT implementation in current LBC schemes. All these merits make it possible to replace the Montgomery arithmetic with the improved Plantard arithmetic in LBC schemes on some platforms. After applying this novel method to Kyber and NTTRU schemes using 16-bit NTT on Cortex-M4 devices, we show that the proposed design outperforms the known fastest implementation that uses Montgomery and Barrett arithmetic. Specifically, compared with the state-of-the-art Kyber implementation, applying the improved Plantard arithmetic in Kyber results in a speedup of 25.02% and 18.56% for NTT and INTT, respectively. Compared with the reference implementation of NTTRU, our NTT and INTT achieve speedup by 83.21% and 78.64%, respectively. As for the LBC KEM schemes, we set new speed records for Kyber and NTTRU running on Cortex-M4
- …