Access Control Apparatus Using Individual Key ICV Data

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing integrity check technologies face challenges in managing large ICV data sizes, which reduces available memory for program execution, and are vulnerable to tampering due to unique block-ICV correspondences.

Innovation Solution

An access control apparatus that generates and uses ICV data smaller in size than the digest value data, utilizing an individual key to calculate and verify ICVs for blocks, and stores this data in a secure manner to prevent tampering.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If digest value data is stored in memory for integrity check, then verification capability is improved, but memory size available for program execution is reduced

Engineering Contradiction:

Improveintegrity verification capabilityVSAvoidmemory size

Core Design Contradiction:

ReliabilityVSQuantity of substance

Solution Approach 1:

The patent extracts only the necessary portion of digest value data by generating ICV data that is smaller than the full digest value data while still providing integrity verification capability. This selective extraction reduces memory requirements while maintaining verification functionality.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent changes the parameter of data size by generating ICV data with reduced size compared to full digest value data. This parameter transformation allows the system to maintain verification capability with smaller data footprint in memory.

Inventive Principle:

Principle #35Parameter changes

2Measurement precision

If unique correspondence between block and ICV data is established, then integrity check precision is improved, but vulnerability to tampering increases

Engineering Contradiction:

Improveintegrity check precisionVSAvoidtampering vulnerability

Core Design Contradiction:

Measurement precisionVSObject-affected harmful factors

Solution Approach 1:

The patent introduces an intermediary mechanism where ICV data is generated based on verified digest value data but does not directly expose the full digest value. This intermediary layer maintains verification precision while preventing direct tampering with the original digest value data.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent performs preliminary verification by generating ICV data from verified digest value data before actual access operations. This preliminary action ensures integrity is confirmed in advance, preventing tampering during subsequent operations.

Inventive Principle:

Principle #10Preliminary action

Data Source

PatentUS12223096B2Access control apparatus, access control method, and program

Publication Date: 2025.02.11 SONY INTERACTIVE ENTERTAINMENT LLC

AI summary

Provided are an access control apparatus, an access control method, and a program that can reduce risks of tampering with a block while at the same time keeping ICV data size to a minimum. An individual key generation section (52) generates an individual key specific to an information processing apparatus (12). An ICV data generation section (56) generates, by using an individual key, ICV data that is based on verified digest value data, specific to the information processing apparatus (12), and smaller in data size than the digest value data. An ICV calculation section (64) calculates, by using the individual key, an ICV based on the block to which access is requested. A comparison section (66) compares the ICV indicated by a part of the ICV data corresponding to the block with the ICV calculated by the ICV calculation section (64). A writing section (68) writes the block to a memory in a case where the comparison succeeds.