Electronics and Telecommunications Research Institute

Jung Keun Lee

Daesung Kwon

Deukjo Hong

Dong-chan Kim

Woo-Hwan Kim

Sang Woo Park

Bonwook Koo

Dongyoung Roh

Woo Hwan Kim

Kwon Ho Ryu

An apparatus and method for providing a Feistel-based variable length block cipher, which are configured to, when plaintext having a certain bit length is encrypted, generate ciphertext having the same bit length as plaintext, and to decrypt ciphertext into plaintext having the same bit length. The apparatus includes an encryption/decryption key generation unit for generating a number of encryption/decryption keys corresponding to a preset number of rounds, based on a secret key, the length of the secret key, the length of plaintext, and a round constant; an encryption/decryption tweak generation unit for generating an encryption/decryption tweak based on a tweak, a length of tweak, and the length of plaintext; and a ciphertext output unit for outputting ciphertext having length identical to that of plaintext, based on plaintext, the length of the plaintext, the length of the secret key, the encryption/decryption keys, and the encryption/decryption tweak.

Apparatus and method for providing Feistel-based variable length block cipher

An operation apparatus includes a message expansion unit, a state data initiation unit, a state data generation unit, and a chain variable update unit. The message expansion unit generates a plurality of expanded messages using a message. The state data initiation unit generates the initial value of state data using chain variable data. The state data generation unit generates the final value of the state data by iterating a combination function and a step function using the state data and the plurality of expanded messages. The chain variable update unit updates the chain variable data using the state data of the final value.

Operation method and apparatus for providing compression function for fast message hashing

An apparatus and method for performing a compression operation in a hash algorithm are provided. The apparatus includes an interface unit, a message extension unit, a chain variable initial conversion unit, a compression function computation unit, and a chain variable final conversion unit. The interface unit receives a message and chain variable data. The message extension unit generates a plurality of extended messages from the message. The chain variable initial conversion unit converts the chain variable data into initial state data for a compression function. The compression function computation unit repeatedly computes extended message binding and step functions based on the initial state data and the plurality of extended messages, and performs combination with a final extended message, thereby computing final state data. The chain variable final conversion unit generates and outputs chain variable data, into which the chain variable data has been updated, using the final state data.

Apparatus and method for performing compression operation in hash algorithm

An apparatus and method for performing a compression operation in a fast message hash algorithm, which receive a 512-bit message and 512-bit chaining variable data, repeatedly calculate a 128-bit register-based step function, and then produce updated 512-bit chaining variable data. For this, the apparatus for performing a compression operation in a hash algorithm includes a message extension unit for receiving a message and generating a plurality of extended messages. A chaining variable initial conversion unit receives chaining variable data and converts the chaining variable data into initial state data. A step function operation unit repeatedly calculates a step function based on the initial state data and the plurality of extended messages and produces final state data. A chaining variable final conversion unit generates updated chaining variable data from the chaining variable data using the final state data, and outputs the updated chaining variable data.

An encryption apparatus and method that provide a mobile fast block cipher algorithm that supports low-power encryption. The encryption apparatus includes a user interface unit, a key scheduler unit, an initial conversion unit, a round function processing unit, and a final conversion unit. The user interface unit receives plain text to be encrypted and a master key. The key scheduler unit generates a round key from the master key. The initial conversion unit generates initial round function values from the plain text. The round function processing unit repeatedly processes a round function using the round key and the initial round function values. The final conversion unit generates ciphertext from the resulting values of the round function processed in a final round by the round function processing unit.

Low-power encryption apparatus and method

Provided are a cache memory using a linear hash function and a method of operating the same. The cache memory includes: a first hash function module for converting a main memory address received from a central processing unit (CPU) into a first index value using a first hash function; a second hash function module for converting the main memory address into a second index value using a second hash function; a first comparator for comparing a tag value of a data block located at the first index value in the first bank with a tag value of the main memory address; and a second comparator for comparing a tag value of a data block located at the second index value in the second bank with the tag value of the main memory address. In a pair of linear hash functions according to the present invention, each constructed with a 2m&#xd7;m binary matrix, even if m is an odd number, each of the linear hash functions has the highest degree of interbank dispersion and avoids conflicts in row, column, diagonal, anti-diagonal, and rectangular patterns, so that a 2-way skewed associative cache can be constructed in relatively wide ranges.

Cache memory and method of operating the same

Provided are a method of generating a Message Authentication Code (MAC) using a stream cipher, and authentication/encryption and authentication/decryption methods using a stream cipher. According to the methods, authentication/encryption is performed using a MAC generated using a stream cipher as an initialization vector of the stream cipher. Therefore, it is unnecessary to use a random number generation algorithm to generate the initialization vector, and thus implementation efficiency can be improved. In addition, upon generation of a MAC, a plurality of key stream generators perform computation for a plurality of message blocks, respectively. Therefore, the message blocks are computed in parallel at a time, and thus computation efficiency is excellent.

Method of generating message authentication code using stream cipher and authentication/encryption and authentication/decryption methods using stream cipher

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Daejeon, South Korea

Jung Keun Lee