Method for implementing private set intersection protocol using oblivious pseudo-random function based on minicrypt, and terminal device using same

A receiver, the receiver comprising:

• one or more processors configured to execute instructions;
• a memory storing the instructions, which when executed by the processor configure the processor to:
• generate an OKVS (oblivious key-value store) matrix by applying an OKVS encoding algorithm to first data and hash data of the first data;
• apply a linear code encoder to the OKVS matrix to convert the OKVS matrix into a linear matrix including a linear code configured to perform a linear operation;
• receive a preset first group distributed, among vector or scalar parameters responsive to the vector or scalar parameters satisfying a preset linear equation being generated using vector oblivious linear evaluation (VOLE) for a subspace based on Minicrypt;
• generate a masking matrix by masking the linear matrix to a first vector included in the first group and transmitting the masking matrix to a sender;
• and
• generate first comparison data by applying an OKVS decoding algorithm to a second vector included in the first group and the first data.

A sender, the sender comprising:

• one or more processors configured to execute instructions;
• a memory storing the instructions, which when executed by the processor configure the processor to:
• receive a preset second group distributed, among vector or scalar parameters responsive to the vector or scalar parameters satisfying a preset linear equation being generated using vector oblivious linear evaluation (VOLE) for a subspace based on Minicrypt;
• update one vector of the vectors included in the second group using a masking matrix responsive to the masking matrix being obtained by masking a first vector included in a first group being received from a receiver;
• and
• define a pseudo-random function according to an OKVS (oblivious key-value store) decoding algorithm using the updated one vector and apply second data and parameters in the second group to the pseudo-random function to generate second comparison data.