公开(公告)号：US20250139296A1

公开(公告)日：2025-05-01

申请号：US18837269

申请日：2022-02-25

Applicant: NEC Corporation

Inventor： Isamu FURUYA ,  Akiko MUKAI ,  Kazuhiko MINEMATSU

IPC: G06F21/64 ,  G06F21/55

Abstract: A data storage apparatus, including: encoding part; and falsification correction part; wherein the encoding part includes code generation section that generates, based on original data and falsification frequency, a code which enables correction of the original data, and includes a tag generation section that generates a first tag which enables detection of falsification of the original data, based on the original data; wherein the encoding part stores the code and the first tag in a storage part; and wherein the falsification correction part includes a falsified portion determination section that retrieves a falsified code and the first tag from the storage part, generates a second tag based on the falsified code, and determines a falsified portion(s) in the falsified code by using the first tag and the second tag, and includes a data correction section that outputs corrected original data by using the determined falsified portion(s) and the falsified code.

公开(公告)号：US20230139104A1

公开(公告)日：2023-05-04

申请号：US17918643

申请日：2020-04-23

Applicant: NEC Corporation

Inventor： Kazuhiko MINEMATSU ,  Akiko MUKAI ,  Naofumi HOMMA ,  Rei Ueno

IPC: H04L9/32 ,  H04L9/06

Abstract: An authenticated encryption apparatus capable of reducing delays in encryption and in decryption is provided. A nonce generation unit generates a nonce different from any of values generated in the past. A plaintext encryption unit generates a ciphertext corresponding to a plaintext by encrypting each of blocks obtained by dividing the plaintext by using the nonce as an auxiliary variable. A checksum generation unit generates a checksum by using the plaintext. A hash unit acquires a hash value. A nonce encryption unit acquires an encrypted nonce by encrypting the nonce. An authentication tag generation unit generates an authentication tag by using the checksum, the hash value, and the encrypted nonce.

公开(公告)号：US20250047464A1

公开(公告)日：2025-02-06

申请号：US18709111

申请日：2021-11-25

Applicant: NEC Corporation

Inventor： Akiko MUKAI

IPC: H04L9/06 ,  H04L9/32

Abstract: A random number calculation unit generates a set of random numbers for each area by using first data and a predetermined matrix having predetermined values as elements, the first data being derived, in the encryption, from at least one of an input and an output of a function related to the Tweakable block cipher in each area. A random number encryption unit encrypts the set of random numbers generated in each area by using the Tweakable block cipher. Each of the encrypted random numbers becomes an initial value used in processing in the next area. A tag generation unit encrypts the set of random numbers generated in the last area by using the Tweakable block cipher, and thereby generates an authentication tag.

公开(公告)号：US20230132163A1

公开(公告)日：2023-04-27

申请号：US17918597

申请日：2020-04-23

Applicant: NEC Corporation

Inventor： Akiko MUKAI ,  Kazuhiko MINEMATSU ,  Naofumi HOMMA ,  Rei UENO

IPC: H04L9/32 ,  H04L9/08 ,  H04L9/06

Abstract: A memory address allocation unit allocates, to each of nodes in a tree structure configured for protecting a memory, a memory address unique to the node. A tag generation unit defines, for each of the nodes in the tree structure, a connection of the memory address and a constant as a nonce, and generates a tag by inputting the nonce and a plaintext of which tampering with is to be detected, or the nonce and a plurality of constants of child nodes of each of the nodes into a message authentication code, the message authentication code being a code by which a partially-updatable tag can be output. A node generation unit uses a constant as a local counter, and generates each of the nodes in the tree structure by combining at least a tag and the local counter.

公开(公告)号：US20230134515A1

公开(公告)日：2023-05-04

申请号：US17800403

申请日：2020-02-28

Applicant: NEC CORPORATION

Inventor： Akiko MUKAI

IPC: H04L9/06 ,  H04L9/32

Abstract: An authentication encryption device generates a mask sequence having, as an element, multiplication, in a Galois field, of a basic mask and a primitive element raised to power of an exponent. The basic mask is defined based on an initialization vector, a secret key, and a constant. The primitive element is a primitive element of a multiplicative group of the Galois field. The exponent differs per cleartext block. The authentication encryption device generates a mask for tag generation by multiplication, in the Galois field, of the basic mask and the primitive element of the multiplicative group of the Galois field raised to power of an exponent differing from the exponent in any of the element in the mask sequence.