A Trusted Measurement Method and Device for Printer-Specific Chips

Abstract

The present invention discloses a method and device for trusted measurement of a printer-specific chip, relating to the technical field of printer security. It includes reading the printer-specific chip code by a dedicated chip code verification module, calculating its unique identifier, and storing it in a trusted system password chip; when the printer starts up, the printer operating system and the dedicated chip code verification module perform self-checks; the dedicated chip code verification module reads the printer-specific chip code and calculates its trusted measurement value; and calls a trusted system interface to verify whether the trusted measurement value of the printer-specific chip code is consistent with the unique identifier to achieve trusted measurement. The present invention realizes anti-replacement and anti-tampering of the printer-specific chip code by hierarchically performing trusted measurement on the printer operating system, the dedicated chip code verification module, and the printer-specific chip code in sequence, reduces the security risks of attacking the printer through the printer-specific chip code, and comprehensively ensures the integrity and reliability of the printer.

Description

Technical Field

[0001] The present invention relates to the technical field of printer security, and particularly to a method and device for trusted measurement of a printer-specific chip, a printer, and a computer-readable storage medium. Background Art

[0002] Printers usually need to use a dedicated chip to complete specific functions. For example, a toner cartridge technology chip is used to monitor the usage status and count of the toner cartridge. Currently, trusted systems are usually used to ensure the trustworthiness of the core software and application software of the operating system. Limited by the independence of the dedicated chip, the code of the dedicated chip is usually not protected by the trusted system, and there is a risk that the dedicated chip may be tampered with by a third party. For example, malicious code may be implanted, or the chip with implanted malicious code may be replaced. Existing security measures usually involve anti-counterfeiting verification of the dedicated chip to prevent the dedicated chip from being counterfeited. However, there is a lack of real-time trusted measurement of the code of the dedicated chip. Even if the original genuine printer-specific chip passes the anti-counterfeiting verification, the execution code in it may be tampered with by a third party, and the threats of information leakage and data tampering caused by the untrustworthiness of the dedicated chip cannot be detected and prevented in a timely manner. Therefore, there is an urgent need for a method to ensure the data integrity and reliability of the dedicated chip. Summary of the Invention

[0003] Aiming at the problem that in existing embedded system devices such as printers, it is impossible to detect whether the dedicated chip is replaced or the chip execution code is tampered with, the present invention provides a method and device for trusted measurement of a printer-specific chip, a printer, and a computer-readable storage medium, to achieve trusted measurement of the code of the dedicated chip and comprehensively ensure the security and reliability of the printer.

[0004] In a first aspect, the present invention provides a method for trusted measurement of a printer-specific chip, including:

[0005] Read the code of the dedicated chip on the printer accessory through a dedicated chip code verification module, calculate the unique identifier of the dedicated chip code, and pre-store the unique identifier in the password chip of the printer trusted system that cannot be modified;

[0006] When the printer starts up, read the dedicated chip code and calculate the trusted measurement value of the dedicated chip code;

[0007] Verify whether the trusted measurement value is consistent with the unique identifier. If it is, it is determined that the dedicated chip code has not been tampered with, and the printer is allowed to run normally. Otherwise, it is determined that the dedicated chip code has been tampered with, the startup of the printer is stopped, and an alarm is issued.

[0008] Furthermore, it also includes calculating the unique identifiers of the main code of the printer operating system and the dedicated chip code verification module, and pre-storing them in the password chip.

[0009] Further, it also includes that when the printer starts, calculate and obtain the trusted measurement value of the main code of the operating system, and call the unique identifier of the main code of the operating system pre-stored in the password chip to perform trusted verification with the trusted measurement value of the main code of the operating system. If the two are consistent, the verification passes; calculate and obtain the trusted measurement value of the dedicated chip code verification module, and call the unique identifier of the dedicated chip code verification module pre-stored in the password chip to perform trusted verification with the trusted measurement value of the dedicated chip code verification module. If the two are consistent, the verification passes.

[0010] Further, the reading of the dedicated chip code on the printer accessory by the dedicated chip code verification module includes:

[0011] Obtain the identification code, relevant production information of the dedicated chip, and the check code pre-stored in the dedicated chip through the dedicated chip code verification module. The check code is generated by encrypting the identification code and the relevant production information with a private key, and the public key corresponding to the private key is pre-stored in the password chip of the printer;

[0012] The dedicated chip code verification module calls the pre-stored public key to decrypt the check code to obtain decrypted data, and performs authenticity verification on the dedicated chip by comparing the decrypted data with the obtained identification code and relevant production information;

[0013] After the authenticity verification passes, the dedicated chip code verification module sends a code acquisition instruction to read the dedicated chip code from the memory area where the specified code address of the dedicated chip is located.

[0014] In a second aspect, the present invention provides a trusted measurement device for a printer dedicated chip, including:

[0015] A preprocessing module, configured to read the dedicated chip code on the printer accessory through the dedicated chip code verification module, calculate the unique identifier of the dedicated chip code, and pre-store the unique identifier into the password chip that cannot be changed in the printer trusted system;

[0016] A trusted computing module, configured to read the dedicated chip code when the printer starts, and calculate the trusted measurement value of the dedicated chip code;

[0017] A trusted measurement module, configured to verify whether the trusted measurement value is consistent with the unique identifier. If so, it is determined that the dedicated chip code has not been tampered with, and the printer is allowed to run normally. Otherwise, it is determined that the dedicated chip code has been tampered with, the startup of the printer is stopped, and an alarm is issued.

[0018] Further, it further includes a self-check preprocessing module, which is configured to calculate and obtain the unique identifier of the main code of the printer operating system and the unique identifier of the dedicated chip code verification module, and pre-store them in the password chip.

[0019] Further, it further includes a self-check module, which is configured to, when the printer starts up, calculate and obtain the trusted measurement value of the main code of the operating system, and call the unique identifier of the main code of the operating system pre-stored in the password chip to perform a trusted verification with the trusted measurement value of the main code of the operating system. If the two are consistent, the verification passes; calculate and obtain the trusted measurement value of the dedicated chip code verification module, and call the unique identifier of the dedicated chip code verification module pre-stored in the password chip to perform a trusted verification with the trusted measurement value of the dedicated chip code verification module. If the two are consistent, the verification passes.

[0020] Further, the preprocessing module is further configured to,

[0021] obtain the identification code, relevant production information of the dedicated chip, and the check code pre-stored in the dedicated chip through the dedicated chip code verification module. The check code is generated by encrypting the identification code and the relevant production information with a private key, and the public key corresponding to the private key is pre-stored in the password chip of the printer;

[0022] The dedicated chip code verification module calls the pre-stored public key to decrypt the check code to obtain decrypted data, and verifies the authenticity of the dedicated chip by comparing the decrypted data with the obtained identification code and relevant production information;

[0023] After the authenticity verification passes, the dedicated chip code verification module sends a code acquisition instruction to read the dedicated chip code from the memory area where the specified code address of the dedicated chip is located.

[0024] In a third aspect, the present invention provides a printer, including:

[0025] One or more processing devices;

[0026] A storage device for storing one or more programs;

[0027] A printer dedicated chip, which is arranged on a printer accessory and is communicatively connected to the processing device through a dedicated interface;

[0028] When the one or more programs are executed by the one or more processing devices, the one or more processing devices implement the above-mentioned method for trusted measurement of a printer dedicated chip.

[0029] Fourthly, the present invention provides a computer-readable storage medium, on which a computer program is stored, and the computer program is executed by a processor to implement the above-mentioned printer-specific chip trust measurement method.

[0030] The beneficial effects of the present invention are as follows: the dedicated chip code verification application reads the dedicated chip code and calls the trusted system for trust measurement, further realizing the anti-tampering of the printer-specific chip on the basis of the anti-counterfeiting of the printer-specific chip, reducing the possibility of an attacker replacing the dedicated chip or tampering with the code executed by the dedicated chip, and reducing the security risk of attacking the printer through the dedicated chip. Description of the Drawings

[0031] By reading the detailed description of the non-limiting embodiments with reference to the following drawings, other features, objectives, and advantages of the present application will become more apparent:

[0032] Figure 1 is a schematic flowchart of a printer-specific chip trust measurement method provided by an embodiment of the present application;

[0033] Figure 2 is a schematic structural diagram of a printer-specific chip trust measurement device provided by an embodiment of the present application;

[0034] Figure 3 is a schematic structural diagram of a printer provided by an embodiment of the present application. Detailed Embodiments

[0035] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0036] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The singular forms "a", "the", and "said" used in the embodiments of the present invention and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0037] It should be understood that although the terms first, second, third, etc. may be used to describe the acquisition modules in the embodiments of the present invention, these acquisition modules should not be limited to these terms. These terms are only used to distinguish the acquisition modules from each other.

[0038] Depending on the context, as used herein, the term "if" may be interpreted as "when" or "while" or "in response to determining" or "in response to detecting". Similarly, depending on the context, the phrase "if determined" or "if detected (stated condition or event)" may be interpreted as "when determined" or "in response to determining" or "when detected (stated condition or event)" or "in response to detecting (stated condition or event)".

[0039] It should be noted that the orientation terms such as "upper", "lower", "left", and "right" described in the embodiments of the present invention are described from the angles shown in the drawings and should not be construed as limitations on the embodiments of the present invention. In addition, in the context, it should also be understood that when it is mentioned that an element is formed "on" or "under" another element, it can not only be directly formed "on" or "under" another element, but also be indirectly formed "on" or "under" another element through an intermediate element.

[0040] See Figure 1 , embodiments of the present invention provide a method for trusted measurement of a printer - specific chip, including the following steps:

[0041] S101, read the dedicated chip code on the printer accessory through the dedicated chip code verification module, calculate the unique identifier of the dedicated chip code, and pre - store the unique identifier in the unmodifiable password chip of the printer trusted system;

[0042] Specifically, develop a dedicated chip code verification module in the printer firmware operating environment in advance. Reading the dedicated chip code on the printer accessory through the dedicated chip code verification module includes:

[0043] First, obtain the identification code, relevant production information of the dedicated chip, and the check code pre - stored in the dedicated chip through the dedicated chip code verification module;

[0044] Among them, the dedicated chip has an identity identification code, model, production date and other relevant production information, and generates a pair of keys during the production stage. The identification code and the relevant production information of the dedicated chip are encrypted through the private key to generate a check code, the check code is stored in the dedicated chip, and the public key is pre - stored in the password chip of the printer.

[0045] Second, the dedicated chip code verification module calls the pre - stored public key to decrypt the check code to obtain decrypted data, and verifies the authenticity of the dedicated chip by comparing the decrypted data with the obtained identification code and relevant production information;

[0046] After the verification passes, the dedicated chip code verification module sends a code acquisition instruction to read the dedicated chip code from the memory area where the dedicated chip specified code address is located.

[0047] After reading the dedicated chip code on the printer accessory through the dedicated chip code verification module, the unique identifier of the dedicated chip code is calculated. Exemplarily, the printer accessories include toner cartridges, ink cartridges, etc. The printer dedicated chips are toner cartridge chips, ink cartridge chips, etc. The toner cartridge chip code, i.e., the execution code, includes a counting program, etc. Then, through a hash function, the dedicated chip code is converted and output as a fixed-length string as the unique identifier of the dedicated chip code. During the printer production stage, it is stored in the password chip of the printer's trusted system that cannot be modified. The hash functions include MD5, SHA, etc.

[0048] In addition, the unique identifier of the printer operating system main code and the unique identifier of the dedicated chip code verification module are calculated through a hash function and pre-stored in the above password chip.

[0049] S102. When the printer starts, read the dedicated chip code and calculate the trusted measurement value of the dedicated chip code.

[0050] Specifically, when the printer starts, first calculate the trusted measurement value of the operating system main code by using the same hash function as in the pre-storage stage, and call the unique identifier of the operating system main code pre-stored in the password chip to perform trusted verification with the trusted measurement value of the operating system main code. If the two are consistent, the verification passes; calculate the trusted measurement value of the dedicated chip code verification module, and call the unique identifier of the dedicated chip code verification module pre-stored in the password chip to perform trusted verification with the trusted measurement value of the dedicated chip code verification module. If the two are consistent, the verification passes, thereby ensuring that the dedicated chip code verification module itself has not been tampered with and guaranteeing that it is safe and trusted to further read the dedicated chip code through this dedicated chip code verification module.

[0051] After passing the trusted verification, the dedicated chip code verification module reads the dedicated chip code by using the same method as in step S101 and calculates the trusted measurement value of the dedicated chip code by using the same hash function as in the pre-storage stage.

[0052] S103. Verify whether the trusted measurement value is consistent with the unique identifier. If so, determine that the dedicated chip code has not been tampered with and let the printer run normally; otherwise, determine that the dedicated chip code has been tampered with, stop the startup of the printer, and issue an alarm.

[0053] Specifically, after the dedicated chip code verification module obtains the trusted measurement value of the dedicated chip code, it calls the trusted system interface and verifies whether the trusted measurement value of the dedicated chip code is consistent with the unique identifier of the dedicated chip code pre-stored in the cryptographic chip through the pre-set trusted measurement program in the cryptographic chip. The dedicated chip code and its unique identifier are uniquely corresponding through a hash function. If the dedicated chip code is tampered with by a third party after leaving the factory, when the printer installs this dedicated chip, the trusted measurement value calculated by the dedicated chip code verification module reading this dedicated chip code is inconsistent with the unique identifier of the dedicated chip code pre-stored in the printer trusted system cryptographic chip during the production stage, it can be determined that the dedicated chip code has been tampered with, and the trusted system is notified to stop the printer from continuing to start and issue an alarm.

[0054] A method for trusted measurement of a printer dedicated chip provided in this embodiment is based on Trusted System 3.0. Without interfering with the original printer operating system, it performs trusted measurement on the printer operating system, dedicated chip code verification module, and dedicated chip code hierarchically in sequence. On the basis of dedicated chip anti-counterfeiting, it further realizes anti-replacement and anti-tampering of the dedicated chip code, reduces the security risks of attacking the printer through the dedicated chip code, and comprehensively guarantees the integrity and reliability of the printer.

[0055] Reference Figure 2 , an embodiment of the present invention further provides a printer dedicated chip trusted measurement device 200, including:

[0056] A preprocessing module 201, configured to read the dedicated chip code on the printer accessory through the dedicated chip code verification module, calculate the unique identifier of the dedicated chip code, and pre-store the unique identifier into the non-changeable cryptographic chip of the printer trusted system;

[0057] A trusted computing module 202, configured to read the dedicated chip code when the printer starts, and calculate the trusted measurement value of the dedicated chip code;

[0058] A trusted measurement module 203, configured to verify whether the trusted measurement value is consistent with the unique identifier. If so, it is determined that the dedicated chip code has not been tampered with, and the printer is allowed to run normally. Otherwise, it is determined that the dedicated chip code has been tampered with, the start of the printer is stopped, and an alarm is issued.

[0059] Further, it further includes a self-check preprocessing module, configured to calculate the unique identifier of the main code of the printer operating system and the unique identifier of the dedicated chip code verification module, and pre-store them in the cryptographic chip.

[0060] Further, it further includes a self-check module, which is configured to calculate and obtain the trust measurement value of the main code of the operating system when the printer is started, and call the unique identifier of the main code of the operating system pre-stored in the password chip to perform trust verification with the trust measurement value of the main code of the operating system. If the two are consistent, the verification passes; calculate and obtain the trust measurement value of the dedicated chip code verification module, and call the unique identifier of the dedicated chip code verification module pre-stored in the password chip to perform trust verification with the trust measurement value of the dedicated chip code verification module. If the two are consistent, the verification passes.

[0061] Further, the preprocessing module 201 is further configured to

[0062] obtain the identification code of the dedicated chip and the check code pre-stored in the dedicated chip through the dedicated chip code verification module, and the check code is obtained by encrypting the identification code and the relevant production information of the dedicated chip through an encryption algorithm;

[0063] decrypt the check code through the dedicated chip code verification module to obtain decryption data, and authenticate the authenticity of the dedicated chip by comparing the decryption data with the identification code;

[0064] After the authenticity verification passes, the dedicated chip code verification module sends a code acquisition instruction to read the dedicated chip code from the memory area where the specified code address of the dedicated chip is located.

[0065] See Figure 3 , another embodiment of the present invention further provides a printer 300 for implementing the above-mentioned method for trusted measurement of a printer dedicated chip. The printer 300 may include a processing device (such as a central processing unit, a graphics processing unit, etc.) 301, which may perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) 302 or a program loaded from a storage device 308 into a random access memory (RAM) 303 to implement the methods of the embodiments described in the present invention. In the RAM 303, various programs and data required for the operation of the printer 300 are also stored. The processing device 301, the ROM 302, and the RAM 303 are connected to each other through a bus 304. An input / output (I / O) interface 305 is also connected to the bus 304.

[0066] Generally, the following devices may be connected to the I / O interface 305: an input device 306 including, for example, a touch screen, a touch pad, a keyboard, a mouse, a camera, a microphone, an accelerometer, a gyroscope, etc.; an output device 307 including, for example, a liquid crystal display (LCD), a speaker, a vibrator, etc.; a storage device 308 including, for example, a magnetic tape, a hard disk, etc.; and a communication device 309. The communication device 309 may allow the printer 300 to communicate with other devices wirelessly or wiredly to exchange data. AlthoughFigure 3 Printer 300 is shown with various devices, but it should be understood that it is not required to implement or have all the devices shown. More or fewer devices may be implemented or had alternatively.

[0067] In particular, according to an embodiment of the present invention, the process described above with reference to the flowchart can be implemented as a computer software program. For example, an embodiment of the present invention includes a computer program product, which includes a computer program carried on a non-transitory computer-readable medium. The computer program contains program code for executing the method shown in the flowchart, so as to implement the method described above. In such an embodiment, the computer program can be downloaded and installed from the network through the communication device 309, or installed from the storage device 308, or installed from the ROM 302. When the computer program is executed by the processing device 301, the above functions defined in the method of the embodiment of the present invention are executed.

[0068] Another embodiment of the present invention also provides a computer-readable storage medium, which may be included in the above-mentioned electronic device; or may exist separately without being assembled into the electronic device. It can be realized when the computer program is executed by the processor.

[0069] The above description is only a preferred embodiment of the present invention. Those skilled in the art should understand that the scope of disclosure involved in the present invention is not limited to the technical solution formed by the specific combination of the above technical features, and should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the above disclosure concept. For example, the technical solution formed by mutually replacing the above features with the technical features (but not limited to) having similar functions disclosed in the present invention.

Claims

1. A method for trusted measurement of a printer-specific chip, characterized in that Comprising: Reading the dedicated chip code on the printer accessory through a dedicated chip code verification module, calculating the unique identifier of the dedicated chip code, and pre-storing the unique identifier into the unchangeable password chip of the printer trusted system; Calculating the unique identifier of the printer operating system main code and the unique identifier of the dedicated chip code verification module, and pre-storing them in the password chip; When the printer starts up, calculating and obtaining the trusted measurement value of the operating system main code, calling the unique identifier of the operating system main code pre-stored in the password chip to perform a trusted verification with the trusted measurement value of the operating system main code, and if they are consistent, the verification passes; calculating and obtaining the trusted measurement value of the dedicated chip code verification module, and calling the unique identifier of the dedicated chip code verification module pre-stored in the password chip to perform a trusted verification with the trusted measurement value of the dedicated chip code verification module, and if they are consistent, the verification passes; When the printer starts up, reading the dedicated chip code and calculating the trusted measurement value of the dedicated chip code; Verifying whether the trusted measurement value is consistent with the unique identifier, if so, determining that the dedicated chip code has not been tampered with, enabling the printer to run normally, otherwise determining that the dedicated chip code has been tampered with, stopping the startup of the printer, and issuing an alarm.

2. The method for trustworthy measurement of a printer-specific chip according to claim 1, characterized in that The reading of the dedicated chip code on the printer accessory through the dedicated chip code verification module includes: Obtaining the identification code, relevant production information of the dedicated chip, and the check code pre-stored in the dedicated chip through the dedicated chip code verification module, where the check code is generated by encrypting the identification code and the relevant production information with a private key, and the public key corresponding to the private key is pre-stored in the password chip of the printer; The dedicated chip code verification module calls the pre-stored public key to decrypt the check code to obtain decrypted data, and verifies the authenticity of the dedicated chip by comparing the decrypted data with the obtained identification code and relevant production information; After the authenticity verification passes, the dedicated chip code verification module sends a code acquisition instruction to read the dedicated chip code from the memory area where the dedicated chip specified code address is located.

3. A trusted measurement device for a printer-specific chip, characterized in that, Comprising: A preprocessing module configured to read the dedicated chip code on the printer accessory through a dedicated chip code verification module, calculate the unique identifier of the dedicated chip code, and pre-store the unique identifier into the unchangeable password chip of the printer trusted system; A self-check preprocessing module configured to calculate the unique identifier of the printer operating system main code and the unique identifier of the dedicated chip code verification module, and pre-store them in the password chip; A self-check module, configured to calculate and obtain a trusted measurement value of the main code of the operating system when the printer is started, call the unique identifier of the main code of the operating system pre-stored in the password chip to perform trusted verification with the trusted measurement value of the main code of the operating system, and pass the verification if the two are consistent; calculate and obtain a trusted measurement value of the dedicated chip code verification module, and call the unique identifier of the dedicated chip code verification module pre-stored in the password chip to perform trusted verification with the trusted measurement value of the dedicated chip code verification module, and pass the verification if the two are consistent; A trusted computing module, configured to read the dedicated chip code when the printer is started and calculate a trusted measurement value of the dedicated chip code; A trusted measurement module, configured to verify whether the trusted measurement value is consistent with the unique identifier, if so, determine that the dedicated chip code has not been tampered with, and allow the printer to run normally, otherwise determine that the dedicated chip code has been tampered with, stop the startup of the printer, and issue an alarm.

4. The trusted measurement device for a printer dedicated chip according to claim 3, wherein The preprocessing module is further configured to obtain the identification code, relevant production information of the dedicated chip and the check code pre-stored in the dedicated chip through the dedicated chip code verification module, and the check code is generated by encrypting the identification code and the relevant production information with a private key, and the public key corresponding to the private key is pre-stored in the password chip of the printer; The dedicated chip code verification module calls the pre-stored public key to decrypt the check code to obtain decryption data, and verifies the authenticity of the dedicated chip by comparing the decryption data with the obtained identification code and relevant production information; After the authenticity verification passes, the dedicated chip code verification module sends a code acquisition instruction to read the dedicated chip code from the memory area where the dedicated chip specified code address is located.

5. A printer, characterized in that, Including: One or more processing devices; A storage device for storing one or more programs; A printer dedicated chip, arranged in a printer accessory and communicatively connected to the processing device through a dedicated interface; When the one or more programs are executed by the one or more processing devices, the one or more processing devices implement a trusted measurement method for a printer dedicated chip as described in claim 1 or 2.

6. A computer-readable storage medium having a computer program stored thereon, characterized in that, The computer program, when executed by a processor, implements the trusted measurement method for a printer dedicated chip as described in claim 1 or 2.

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