Authenticated encryption device, authenticated encryption method, and computer readable medium
AssigneeMitsubishi Electric Corporation
InventorYusuke NAITO
Life of this patent
Estimating the term…
Abstract
An initial processing unit (21) generates a secret value B from a secret key in authenticated encryption. A function F processing unit (22) repeats a process of setting the secret value B generated by the initial processing unit (21) as an input block of a block cipher, and updating the secret value B using the block cipher. A ciphertext processing unit (23) executes at least one of a process of encrypting a plaintext M and a process of decrypting a ciphertext C, using the secret value B updated by the function F processing unit (23).
Claims18
An authenticated encryption device comprising
- processing circuitry to:
- generate a key component K1 of r bits extracted from a secret key of r+n bits in authenticated encryption, and generate a key component K2 of n bits as a secret value B, the key component K2 being the n bits that remain after the key components K1 is extracted from the secret key;
- set a value generated using a value T that is the key component K1 as a key component of a block cipher, set the secret value B as an input block of the block cipher, and update the secret value B using the block cipher;
- and
- execute at least one of a process of encrypting a plaintext M and a process of decrypting a ciphertext C, using the secret value B that has been updated.
An authenticated encryption device comprising
- processing circuitry to:
- generate a secret value B from a secret key in authenticated encryption;
- set the secret value B as an input block of a block cipher, update the secret value B using the block cipher, set a secret value B at a certain time point as a secret value B[0], set a secret value B[i−1] as an input block of a block cipher, and update the secret value B[i−1] using the block cipher to generate a secret value B[i], for each integer i in ascending order, where i=1, . . . , m;
- and
- execute at least one of a process of encrypting a plaintext M and a process of decrypting a ciphertext C using the secret value B[i] for each integer i, where i=1, . . . , m.
An authenticated encryption method comprising:
- generating a key component K1 of r bits extracted from a secret key of r+n bits in authenticated encryption, and generating a key component K2 of n bits as a secret value B, the key component K2 being the n bits that remain after the key components K1 is extracted from the secret key;
- setting a value generated using a value T that is the key component K1 as a key component of a block cipher, setting the secret value B as an input block of the block cipher, and updating the secret value B using the block cipher;
- and
- executing at least one of a process of encrypting a plaintext M and a process of decrypting a ciphertext C, using the secret value B that has been updated.
A non-transitory computer readable medium storing an authenticated encryption program that causes a computer to function as an authenticated encryption device to perform:
- an initial process of generating a key component K1 of r bits extracted from a secret key of r+n bits in authenticated encryption, and generating a key component K2 of n bits as a secret value B, the key component K2 being the n bits that remain after the key components K1 is extracted from the secret key;
- a function F process of setting a value generated using a value T that is the key component K1 generated by the initial process as a key component of a block cipher, setting the secret value B generated by the initial process as an input block of the block cipher, and updating the secret value B using the block cipher;
- and
- a ciphertext process of executing at least one of a process of encrypting a plaintext M and a process of decrypting a ciphertext C, using the secret value B updated by the function F process.
An authenticated encryption method comprising:
- generating a secret value B from a secret key in authenticated encryption;
- setting the secret value B as an input block of a block cipher, updating the secret value B using the block cipher, setting a secret value B at a certain time point as a secret value B[0], setting a secret value B[i−1] as an input block of a block cipher, and updating the secret value B[i−1] using the block cipher to generate a secret value B[i], for each integer i in ascending order, where i=1, . . . , m;
- and
- executing at least one of a process of encrypting a plaintext M and a process of decrypting a ciphertext C using the secret value B[i] for each integer i, where i=1, . . . , m.
A non-transitory computer readable medium storing an authenticated encryption program that causes a computer to function as an authenticated encryption device to perform:
- an initial process of generating a secret value B from a secret key in authenticated encryption;
- a function F process of setting the secret value B generated by the initial process as an input block of a block cipher, and updating the secret value B using the block cipher, the function F process setting a secret value B at a certain time point as a secret value B[0], setting a secret value B[i−1] as an input block of a block cipher, and updating the secret value B[i−1] using the block cipher to generate a secret value B[i], for each integer i in ascending order, where i=1, . . . , m;
- and
- a ciphertext process of executing at least one of a process of encrypting a plaintext M and a process of decrypting a ciphertext C using the secret value B[i] for each integer i, where i=1, . . . , m, generated by the function F process.
Dependencies are inferred from the claim text.