Printer dedicated chip trusted measurement method and device

Abstract

The invention discloses a trusted measurement method and device for a special chip of a printer, and relates to the technical field of printer security. Comprising the following steps: reading a special chip code through a special chip code verification module, calculating a unique identifier of the special chip code, and storing the unique identifier into a trusted system cryptographic chip; when the printer is started, the printer operating system and the special chip code verification module carry out self-detection; the special chip code verification module reads a special chip code and calculates a credibility measurement value of the special chip code; and calling a trusted system interface to verify whether the trusted measurement value of the special chip code is consistent with the unique identifier so as to realize trusted measurement. According to the method, trusted measurement is carried out on the printer operating system, the special chip code verification module and the special chip code in sequence in a hierarchical manner, so that the special chip code is prevented from being replaced and tampered, the potential safety hazard that the printer is attacked through the special chip code is reduced, and the completeness and reliability of the printer are comprehensively guaranteed.

Description

Technical Field

[0001] The present invention relates to the field of printer security technology, and in particular to a printer-specific chip trust measurement method, device, printer and computer-readable storage medium. Background Art

[0002] Printers usually need to use dedicated chips to complete specific functions. For example, the toner cartridge technology chip is used to monitor the toner cartridge usage status and count. The current trusted system is usually used to ensure the credibility of the operating system core software and application software. Due to the independence of the dedicated chip, the code of the dedicated chip is usually not placed under the protection of the trusted system. The dedicated chip is at risk of being tampered with by a third party. For example, it may be implanted with malicious code or replaced by a chip implanted with malicious code. Existing security measures usually perform anti-counterfeiting verification on the dedicated chip to prevent the dedicated chip from being imitated. However, there is a lack of real-time trust measurement of the dedicated chip code. Even the original genuine printer dedicated chip that has passed the anti-counterfeiting verification may have its execution code tampered with by a third party. It is impossible to timely discover and prevent the threat of information leakage and data tampering caused by the unreliability of the dedicated chip. Therefore, there is an urgent need for a method to ensure the integrity and reliability of the dedicated chip data. Summary of the invention

[0003] In view of the problem that existing embedded system devices such as printers cannot detect that the dedicated chip has been replaced or the chip execution code has been tampered with, the present invention provides a method and device for measuring the trustworthiness of a printer dedicated chip, a printer, and a computer-readable storage medium to achieve trustworthiness measurement of the dedicated chip code, so as to fully ensure the safety and reliability of the printer.

[0004] In a first aspect, the present invention provides a method for measuring the trustworthiness of a printer-specific chip, comprising: The dedicated chip code verification module reads the dedicated chip code on the printer accessory, calculates the unique identifier of the dedicated chip code, and stores the unique identifier in advance in the unchangeable password chip of the printer trusted system; When the printer is started, the dedicated chip code is read and a trust metric value of the dedicated chip code is calculated; Verify whether the trust metric value is consistent with the unique identifier. If yes, determine that the dedicated chip code has not been tampered with and allow the printer to operate normally. Otherwise, determine that the dedicated chip code has been tampered with, stop starting the printer, and issue an alarm.

[0005] Furthermore, the method further includes calculating and obtaining a unique identifier of the printer operating system main code and a unique identifier of the dedicated chip code verification module, and pre-storing them in the password chip.

[0006] Furthermore, it also includes that when the printer is started, the trust measurement value of the operating system main code is calculated and obtained, and the unique identifier of the operating system main code pre-stored in the cryptographic chip and the trust measurement value of the operating system main code are called for trust verification, and the verification is successful if the two are consistent; the trust measurement value of the dedicated chip code verification module is calculated and obtained, and the unique identifier of the dedicated chip code verification module pre-stored in the cryptographic chip and the trust measurement value of the dedicated chip code verification module are called for trust verification, and the verification is successful if the two are consistent.

[0007] Further, the step of reading the dedicated chip code on the printer accessory through the dedicated chip code verification module includes: The identification code of the dedicated chip, relevant production information and a check code pre-stored in the dedicated chip are obtained through a 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 verification code to obtain decrypted data, and verifies the authenticity of the dedicated chip by comparing the decrypted data with the obtained identification code and related production information; After the authenticity verification is passed, the dedicated chip code verification module sends a code acquisition instruction to read the dedicated chip code from the memory interval where the dedicated chip specifies the code address.

[0008] In a second aspect, the present invention provides a printer-specific chip trust measurement device, comprising: A preprocessing module is 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 in an unchangeable password chip of the printer trusted system; A trusted computing module is configured to read the dedicated chip code and calculate a trust metric value of the dedicated chip code when the printer is started; The trust measurement module is configured to verify whether the trust 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 operates 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.

[0009] Furthermore, it also includes a self-check pre-processing module, which is configured to calculate the unique identifier of the printer operating system main code and the unique identifier of the dedicated chip code verification module, which are pre-stored in the password chip.

[0010] Furthermore, it also includes a self-test module, which is configured to calculate and obtain the trust value of the operating system main code when the printer is started, call the unique identifier of the operating system main code pre-stored in the cryptographic chip and the trust value of the operating system main code for trust verification, and if the two are consistent, the verification is successful; calculate and obtain the trust value of the dedicated chip code verification module, and call the unique identifier of the dedicated chip code verification module pre-stored in the cryptographic chip and the trust value of the dedicated chip code verification module for trust verification, and if the two are consistent, the verification is successful.

[0011] Furthermore, the preprocessing module is further configured to: The identification code of the dedicated chip, relevant production information and a check code pre-stored in the dedicated chip are obtained through a 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 verification code to obtain decrypted data, and verifies the authenticity of the dedicated chip by comparing the decrypted data with the obtained identification code and related production information; After the authenticity verification is passed, the dedicated chip code verification module sends a code acquisition instruction to read the dedicated chip code from the memory interval where the dedicated chip specifies the code address.

[0012] In a third aspect, the present invention provides a printer, comprising: one or more processing devices; A storage device for storing one or more programs; A printer-specific chip, which is disposed in the printer accessory and is communicatively connected with the processing device via 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 the above-mentioned printer-specific chip trust measurement method.

[0013] In a fourth aspect, the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program is executed by a processor to implement the above-mentioned printer-specific chip trust measurement method.

[0014] The beneficial effect of the present invention is that by reading the dedicated chip code through the dedicated chip code verification application and calling the trusted system to perform trust measurement, the printer dedicated chip anti-tampering is further realized on the basis of the printer dedicated chip anti-counterfeiting, reducing the possibility of attackers executing codes by replacing the dedicated chip or tampering with the dedicated chip, and reducing the security risks of attacking the printer through the dedicated chip. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Other features, objects and advantages of the present application will become more apparent by reading the detailed description of non-limiting embodiments made with reference to the following drawings: Figure 1 It is a flowchart of a printer-specific chip trust measurement method provided by an embodiment of the present application; Figure 2 It is a schematic diagram of the structure of a printer-specific chip trust measurement device provided by an embodiment of the present application; Figure 3 It is a structural schematic diagram of a printer provided by an embodiment of the present application. DETAILED DESCRIPTION

[0016] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0017] 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", "said" and "the" used in the embodiments of the present invention and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

[0018] 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, the acquisition modules should not be limited to these terms. These terms are only used to distinguish the acquisition modules from each other.

[0019] The word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining" or "in response to detecting", depending on the context. Similarly, the phrases "if it is determined" or "if (stated condition or event) is detected" may be interpreted as "when it is determined" or "in response to determining" or "when detecting (stated condition or event)" or "in response to detecting (stated condition or event)", depending on the context.

[0020] It should be noted that the directional words such as "upper", "lower", "left", and "right" described in the embodiments of the present invention are described at the angles shown in the drawings and should not be understood as limiting 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 formed directly "on" or "under" another element, but also be formed "on" or "under" another element indirectly through an intermediate element.

[0021] See also Figure 1 The embodiment of the present invention provides a method for measuring the credibility of a printer-specific chip, including the following steps: S101, reading a dedicated chip code on a printer accessory through a dedicated chip code verification module, calculating a unique identifier of the dedicated chip code, and pre-storing the unique identifier in an unchangeable password chip of a printer trusted system; Specifically, a dedicated chip code verification module is developed in advance in the printer firmware operating environment, and the dedicated chip code verification module is used to read the dedicated chip code on the printer accessory, including: First, the identification code of the dedicated chip, relevant production information and the verification code pre-stored in the dedicated chip are obtained through the dedicated chip code verification module; Among them, the dedicated chip carries an identity identification code and relevant production information such as model and production date, and generates a pair of keys during the production stage. The identification code and the production information related to the dedicated chip are encrypted with a private key to generate a verification code, which is stored in the dedicated chip, and the public key is pre-stored in the password chip of the printer.

[0022] Secondly, the dedicated chip code verification module calls the pre-stored public key to decrypt the verification code to obtain decrypted data, and verifies the authenticity of the dedicated chip by comparing the decrypted data with the obtained identification code and related production information; After the verification is passed, the dedicated chip code verification module sends a code acquisition instruction to read the dedicated chip code from the memory interval where the dedicated chip specifies the code address.

[0023] After reading the dedicated chip code on the printer accessories through the dedicated chip code verification module, the unique identification of the dedicated chip code is calculated. For example, the printer accessories include toner cartridges, ink cartridges, etc. The printer dedicated chip is the toner cartridge chip, ink cartridge chip, etc. The toner cartridge chip code is the execution code including the counting program, etc. The dedicated chip code is then converted through a hash function to output a fixed-length string as the unique identification of the dedicated chip code. During the printer production stage, it is stored in the unchangeable password chip of the printer's trusted system. The hash function includes MD5, SHA, etc.

[0024] 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 by a hash function and pre-stored in the above-mentioned password chip.

[0025] S102, when the printer is started, reading the dedicated chip code, and calculating the trustworthiness value of the dedicated chip code; Specifically, when the printer is started, it first uses the same hash function calculation as in the pre-storage stage to obtain the trust value of the operating system main code, and calls the unique identifier of the operating system main code pre-stored in the cryptographic chip and the trust value of the operating system main code for trust verification. If the two are consistent, the verification passes; the trust value of the dedicated chip code verification module is calculated to obtain the trust value, and the unique identifier of the dedicated chip code verification module pre-stored in the cryptographic chip and the trust value of the dedicated chip code verification module are called for trust verification. If the two are consistent, the verification passes, thereby ensuring that the dedicated chip code verification module itself has not been tampered with, and ensuring that further reading of the dedicated chip code through the dedicated chip code verification module is safe and reliable.

[0026] After passing the trustworthy verification, the dedicated chip code verification module adopts the same method as step S101 to read the dedicated chip code, and adopts the same hash function calculation as in the pre-storage stage to obtain the trustworthy measurement value of the dedicated chip code.

[0027] S103, verifying whether the trust metric value is consistent with the unique identifier, if yes, determining that the dedicated chip code has not been tampered with, allowing the printer to operate normally, otherwise determining that the dedicated chip code has been tampered with, stopping the startup of the printer, and issuing an alarm.

[0028] Specifically, after the dedicated chip code verification module obtains the trust measurement value of the dedicated chip code, it calls the trusted system interface to verify whether the trust 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 trusted measurement program preset in the cryptographic chip. The dedicated chip code and its unique identifier are uniquely corresponded through a hash function. If the dedicated chip code is tampered with by a third party after leaving the factory, after the printer installs the dedicated chip, the trust measurement value calculated by the dedicated chip code reading the dedicated chip code by the dedicated chip code verification module 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 starting up and issue an alarm.

[0029] The present embodiment provides a method for measuring the trustworthiness of a printer-specific chip. Based on the Trusted System 3.0, the method measures the trustworthiness of the printer operating system, the dedicated chip code verification module, and the dedicated chip code in sequence without interfering with the original printer operating system. On the basis of the dedicated chip anti-counterfeiting, the dedicated chip code is further protected from replacement and tampering, thereby reducing the potential security risks of attacks on the printer through the dedicated chip code and comprehensively ensuring the integrity and reliability of the printer.

[0030] refer to Figure 2 The embodiment of the present invention further provides a printer-specific chip trust measurement device 200, comprising: The preprocessing module 201 is 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 in the unchangeable password chip of the printer trusted system; The trusted computing module 202 is configured to read the dedicated chip code and calculate the trust value of the dedicated chip code when the printer is started; The trust metric module 203 is configured to verify whether the trust metric 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 operates normally. Otherwise, it is determined that the dedicated chip code has been tampered with, the printer is stopped from starting, and an alarm is issued.

[0031] Furthermore, it also includes a self-check pre-processing module, which is configured to calculate the unique identifier of the printer operating system main code and the unique identifier of the dedicated chip code verification module, which are pre-stored in the password chip.

[0032] Furthermore, it also includes a self-test module, which is configured to calculate and obtain the trust value of the operating system main code when the printer is started, call the unique identifier of the operating system main code pre-stored in the cryptographic chip and the trust value of the operating system main code for trust verification, and if the two are consistent, the verification is successful; calculate and obtain the trust value of the dedicated chip code verification module, and call the unique identifier of the dedicated chip code verification module pre-stored in the cryptographic chip and the trust value of the dedicated chip code verification module for trust verification, and if the two are consistent, the verification is successful.

[0033] Furthermore, the preprocessing module 201 is further configured to: The identification code of the dedicated chip and the verification code pre-stored in the dedicated chip are obtained by encrypting the identification code and the relevant production information of the dedicated chip through an encryption algorithm; Decrypting the verification code by a dedicated chip code verification module to obtain decrypted data, and verifying the authenticity of the dedicated chip by comparing the decrypted data with the identification code; After the authenticity verification is passed, the dedicated chip code verification module sends a code acquisition instruction to read the dedicated chip code from the memory interval where the dedicated chip specifies the code address.

[0034] See also Figure 3 Another embodiment of the present invention also provides a printer 300 for implementing the above printer-specific chip trust measurement method. The printer 300 may include a processing device (such as a central processing unit, a graphics processing unit, etc.) 301, which can 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 to a random access memory (RAM) 303 to implement the method of each embodiment 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 via a bus 304. An input / output (I / O) interface 305 is also connected to the bus 304.

[0035] Typically, 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 by wire to exchange data. Although Figure 3 The printer 300 is shown with various devices, but it should be understood that it is not required to implement or have all of the devices shown. More or fewer devices may be implemented or have instead.

[0036] 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, and the computer program includes a program code for executing the method shown in the flowchart, thereby implementing 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-mentioned functions defined in the method of the embodiment of the present invention are executed.

[0037] Another embodiment of the present invention further provides a computer-readable storage medium, which may be included in the above electronic device or may exist independently without being installed in the electronic device. The computer program can be implemented when executed by a processor.

[0038] 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 a specific combination of the above technical features, but also should cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the above disclosed concept. For example, the above features are replaced with the technical features with similar functions disclosed in the present invention (but not limited to) to form a technical solution.

Claims

1. A printer-specific chip trust measurement method, characterized in that: include: The dedicated chip code verification module reads the dedicated chip code on the printer accessory, calculates the unique identifier of the dedicated chip code, and stores the unique identifier in advance in the unchangeable password chip of the printer trusted system; When the printer is started, the dedicated chip code is read and a trust metric value of the dedicated chip code is calculated; Verify whether the trust metric value is consistent with the unique identifier. If yes, determine that the dedicated chip code has not been tampered with and allow the printer to operate normally. Otherwise, determine that the dedicated chip code has been tampered with, stop starting the printer, and issue an alarm.

2. A printer-specific chip trust measurement method according to claim 1, characterized in that: Also includes: The unique identifier of the printer operating system main code and the unique identifier of the dedicated chip code verification module are calculated and pre-stored in the password chip.

3. A printer-specific chip trust measurement method according to claim 2, characterized in that: Also includes: When the printer is started, the trust measurement value of the operating system main code is calculated and obtained, and the unique identifier of the operating system main code pre-stored in the password chip and the trust measurement value of the operating system main code are called for trust verification. If the two are consistent, the verification is successful; the trust measurement value of the dedicated chip code verification module is calculated and obtained, and the unique identifier of the dedicated chip code verification module pre-stored in the password chip and the trust measurement value of the dedicated chip code verification module are called for trust verification. If the two are consistent, the verification is successful.

4. A printer-specific chip trust measurement method according to claim 1, characterized in that: The method of reading the dedicated chip code on the printer accessory by the dedicated chip code verification module includes: The identification code of the dedicated chip, relevant production information and a check code pre-stored in the dedicated chip are obtained through a 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 verification code to obtain decrypted data, and verifies the authenticity of the dedicated chip by comparing the decrypted data with the obtained identification code and related production information; After the authenticity verification is passed, the dedicated chip code verification module sends a code acquisition instruction to read the dedicated chip code from the memory interval where the dedicated chip specifies the code address.

5. A printer-specific chip trust measurement device, characterized in that: include: A preprocessing module is 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 in an unchangeable password chip of the printer trusted system; A trusted computing module is configured to read the dedicated chip code and calculate a trust metric value of the dedicated chip code when the printer is started; The trust measurement module is configured to verify whether the trust 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 operates 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.

6. A printer-specific chip trust measurement device according to claim 5, characterized in that: Also includes: The self-check pre-processing module is configured to calculate and obtain the unique identifier of the printer operating system main code and the unique identifier of the dedicated chip code verification module, which are pre-stored in the password chip.

7. A printer-specific chip trust measurement device according to claim 6, characterized in that: Also includes: The self-check module is configured to, when the printer is started, calculate and obtain the trust value of the main code of the operating system, call the unique identifier of the main code of the operating system pre-stored in the password chip and the trust value of the main code of the operating system for trust verification, and if the two are consistent, the verification is successful; calculate and obtain the trust 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 and the trust value of the dedicated chip code verification module for trust verification, and if the two are consistent, the verification is successful.

8. A printer-specific chip trust measurement device according to claim 6, characterized in that: The preprocessing module is further configured to: The identification code of the dedicated chip, relevant production information and a check code pre-stored in the dedicated chip are obtained through a 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 verification code to obtain decrypted data, and verifies the authenticity of the dedicated chip by comparing the decrypted data with the obtained identification code and related production information; After the authenticity verification is passed, the dedicated chip code verification module sends a code acquisition instruction to read the dedicated chip code from the memory interval where the dedicated chip specifies the code address.

9. A printer, characterized in that: include: one or more processing devices; A storage device for storing one or more programs; A printer-specific chip, which is disposed in the printer accessory and is communicatively connected with the processing device via 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 printer-specific chip trust measurement method as described in any one of claims 1-4.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the printer-specific chip trust measurement method according to any one of claims 1 to 4 is implemented.

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