CRYPTO LAB INC.

A server device is provided. The server device includes an interface configured to communicate with an application device in which an application that uses plaintext data is installed, a memory, and a processor, wherein the processor is configured to generate a homomorphic encrypted master key corresponding to the application device and index information for the master key, store the homomorphic encrypted master key and the index information in the memory, and provide the index information to the application device through the interface. Accordingly, various data processing may be performed, while security is maintained without dedicated hardware.

Disclosed is an electronic device including: a memory storing a lookup table including identification information and data matched to the identification information; an interface; and a processor configured to search the data matched to the identification information corresponding to search information by generating a position identification vector including the number of elements corresponding to the number of the lookup table, and repeatedly performing an operation of updating the position identification vector based on a comparison calculation result based on the search information and each segmented table part while segmenting the lookup table into a plurality of parts, in case of receiving the search information through the interface. Accordingly, the device may perform effective data search on the table including a homomorphically encrypted message.

A text search method is disclosed. The text search method includes, based on a query including a text being input, computing a vector value having a preset size by using a preset encoding algorithm, the vector value corresponding to the text, generating a query ciphertext by homomorphic encryption for the computed vector value, transmitting the generated query ciphertext to a server, receiving a calculation result ciphertext having similarity information with the query for each of a plurality of indexes, determining an index having a preset similarity by restoring the calculation result ciphertext, and receiving information corresponding to the index by transmitting the determined index to the server.

Disclosed is a method of processing an encrypted message. The method of processing an encrypted message includes checking exponential data and mantissa data for numerical data, performing homomorphic encryption on the mantissa data, and merging the encrypted mantissa data and the exponential data to generate a homomorphic encrypted message.

An electronic apparatus is disclosed. The electronic apparatus includes a memory configured to store a homomorphic ciphertext including a tag and a program operating in the electronic apparatus, a user interface, and a processor, and the tag includes type information for original data of the homomorphic ciphertext, and is set, based on computation for the homomorphic ciphertext being performed, such that the tag included in the homomorphic ciphertext used in the computation is included in even a computation result value generated by the computation being performed, and the processor is configured to generate, based on receiving a computation request for the homomorphic ciphertext from the program, a computation result value by performing computation for the homomorphic ciphertext, check the type information for the original data of the homomorphic ciphertext used in the computation based on the tag included in the computation result value, perform decryption of the computation result value, control the user interface to display the checked type information for the original data and the decrypted computation result value, and provide, based on receiving a command to provide data through the user interface, the decrypted computation result value to the program.

An electronic device is disclosed. The present electronic device comprises: a communication device for communicating with an external device; a memory for storing data; and a processor for supporting a trusted execution environment (TEE) function, wherein the processor is configured to store a received open software in a protection zone corresponding to the TEE function, when the open software, signature information corresponding to the open software, and hash information corresponding to the open software are received from the external device, generate a secret key corresponding to the open software, and perform an operation corresponding to the open software by using the open software and the data, stored in the protection zone.

A method for processing homomorphic ciphertexts includes: receiving an input of an instruction for sorting regarding a plurality of homomorphic ciphertexts; sorting the plurality of homomorphic ciphertexts by using a sorter which can sort 3 more homomorphic ciphertexts in a single stage; and outputting the sorting result. The sorter performs sorting by using a comparison function that selectively outputs a bigger value or a smaller value between two input values.

Disclosed is a calculation device. The present calculation device includes: a memory for storing a plurality of homomorphic ciphertexts for an approximate message including an error; and a processor for sorting the plurality of homomorphic ciphertexts by using a 5-way sorter which can sort five homomorphic ciphertexts in a single stage.

Disclosed is an electronic device including: a memory storing a lookup table including identification information and data matched to the identification information; an interface; and a processor configured to search the data matched to the identification information corresponding to search information by generating a position identification vector including the number of elements corresponding to the number of the lookup table, and repeatedly performing an operation of updating the position identification vector based on a comparison calculation result based on the search information and each segmented table part while segmenting the lookup table into a plurality of parts, in case of receiving the search information through the interface. Accordingly, the device may perform effective data search on the table including a homomorphically encrypted message.

Disclosed is an electronic apparatus. The electronic apparatus includes: a memory storing a plurality of homomorphic encryptions and lookup table information; a communication apparatus configured to perform communication with an external apparatus; and a processor configured to retrieve the homomorphic encryption in response to a requested query, wherein the lookup table information stores data acquired by homomorphically encrypting keyword information and index information that respectively correspond to the plurality of homomorphic encryptions, and the processor is configured to retrieve the homomorphically encrypted index information by using received query information and the lookup table information in case of receiving the query information from the external apparatus, and control the communication apparatus to transmit the retrieved index homomorphic encryption to the electronic apparatus.