Falsification detecting system, falsification detecting method, falsification detecting program, recording medium, integrated circuit, authentication information generating device and falsification detecting device

A tamper detection system for detecting tampering with a program, comprising:

• a first processing unit operable to generate in-process authentication data from a first program targeted for execution, by conducting a conversion process based on a parameter determined at random to shorten the first program;
• a first generating unit operable to generate, prior to execution of the first program, authentication information from the in-process authentication data by conducting a summarization process that is higher in computational complexity than the conversion process;
• a holding unit operable to hold the authentication information;
• a second processing unit operable to generate in-process comparative data from the first program by conducting the conversion process based on a parameter that is same as the parameter used by the first processing unit;
• a second generating unit operable to generate, during execution of a second program, comparative information from the in-process comparative data by conducting the summarization process;
• and
• a detection unit operable to detect, during execution of the second program, tampering with the first program, by using the authentication information and the comparative information.

A method for detecting tampering with a program, the method comprising,

• a first converting step of generating in-process authentication data from a first program targeted for execution, by conducting a conversion process based on a parameter determined at random to shorten the first program;
• a first generating step of generating, prior to execution of the first program, authentication information from the in-process authentication data by conducting a summarization process that is higher in computational complexity than the conversion process;
• a holding step of holding the authentication information;
• a second converting step of generating in-process comparative data from the first program by conducting the conversion process based on a parameter that is same as the parameter used by the first processing unit;
• a second generating step of generating, during execution of a second program, comparative information from the in-process comparative data by conducting the summarization process;
• and
• a detecting step of detecting, during execution of the second program, tampering with the first program, by using the authentication information and the comparative information.

A tamper detection program for use by a tamper detection system that detects tampering with a program, the tamper detection program comprising code operable to cause a computer to execute:

• a first converting step of generating in-process authentication data from a first program targeted for execution, by conducting a conversion process based on a parameter determined at random to shorten the first program;
• a first generating step of generating, prior to execution of the first program, authentication information from the in-process authentication data by conducting a summarization process that is higher in computational complexity than the conversion process;
• a holding step of holding the authentication information;
• a second converting step of generating in-process comparative data from the first program by conducting the conversion process based on a parameter that is same as the parameter used in the first processing step;
• a second generating step of generating, during execution of a second program, comparative information from the in-process comparative data by conducting the summarization process;
• and
• a detecting step of detecting, during execution of the second program, tampering with the first program, by using the authentication information and the comparative information.

A computer-readable recording medium storing a tamper detection program comprising code operable to cause a computer to execute:

• a first converting step of generating in-process authentication data from a first program targeted for execution, by conducting a conversion process based on a parameter determined at random to shorten the first program;
• a first generating step of generating, prior to execution of the first program, authentication information from the in-process authentication data by conducting a summarization process that is higher in computational complexity than the conversion process;
• a holding step of holding the authentication information;
• a second converting step of generating in-process comparative data from the first program by conducting the conversion process based on a parameter that is same as the parameter used in the first processing step;
• a second generating step of generating, during execution of a second program, comparative information from the in-process comparative data by conducting the summarization process;
• and
• a detecting step of detecting, during execution of the second program, tampering with the first program, by using the authentication information and the comparative information.

An integrated circuit for detecting tampering with a program, the integrated circuit comprising:

• a first processing unit operable to generate in-process authentication data from a first program targeted for execution, by conducting a conversion process based on a parameter determined at random to shorten the first program;
• a first generating unit operable to generate, prior to execution of the first program, authentication information from the in-process authentication data by conducting a summarization process that is higher in computational complexity than the conversion process;
• a holding unit operable to hold the authentication information;
• a second processing unit operable to generate in-process comparative data from the first program by conducting the conversion process based on a parameter that is same as the parameter used by the first processing unit;
• a second generating unit operable to generate, during execution of a second program, comparative information from the in-process comparative data by conducting the summarization process;
• and
• a detection unit operable to detect, during execution of the second program, tampering with the first program, by using the authentication information and the comparative information.

An authentication information generating device for generating authentication information to be used for detecting tampering with a program, the authentication information generating device comprising:

• a processing unit operable to generate in-process authentication data from a program targeted for execution, by conducting a conversion process based on a parameter determined at random to shorten the target program;
• a generating unit operable to generate, prior to execution of the target program, authentication information from the in-process authentication data by conducting a summarization process that is higher in computational complexity than the conversion process;
• and
• a supplying unit operable to supply the authentication information to a tamper detection device.

A tamper detection device for detecting tampering with a program, the tamper detection device comprising:

• a holding unit operable to hold authentication information that is generated, prior to execution of a first program targeted for execution, from the first program by conducting a conversion process based on a random number to shorten the first program and further conducting a summarization process that is higher in computational complexity than the conversion process;
• a processing unit operable to generate in-process comparative data from the first program by conducting the conversion process based on a parameter that is same as the parameter used by the first processing unit;
• a second generating unit operable to generate, during execution of a second program, comparative information from the in-process comparative data by conducting the summarization process;
• and
• a detection unit operable to detect, during execution of the second program, tampering with the first program, by using the authentication information and the comparative information.