POS machine for data signature, storage medium and tool
By introducing a security design of multiple module combinations in POS machines, the problems of centralized key storage, weak password authentication and insufficient data transmission integrity in POS machines data signatures are solved, and multiple security protection of keys and high reliability of data signatures are achieved.
Patent Information
- Application Number
- CN202510482284.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-17
- Publication Date
- 2025-06-17
AI Technical Summary
When signing data, existing POS machines have problems such as centralized key storage being vulnerable to physical attacks, weak password authentication mechanisms, and insufficient data transmission integrity, resulting in a high risk of key leakage and data tampering.
By introducing card reader module, security authentication module, key synthesis module, security chip module and communication interface module into the POS machine, the RSA private key components that are physically separated are read, the complete key is generated through XOR operation, and stored in the key security protection area, combining dynamic out-of-order password authentication, data block transmission and verification code generation mechanisms to ensure the security of data signatures.
It realizes multiple security protection for the entire life cycle of the key, significantly reducing the risks of physical attacks, password cracking and data tampering, and improving the security and reliability of POS machine data signatures.
Smart Images
Figure CN120164286A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of financial transaction security, and particularly to a POS machine, a storage medium, and a tool for data signature. Background Art
[0002] With the popularization of electronic payment technology, as a key data processing terminal, the security of data signature of the POS machine is of crucial importance. When traditional POS machines implement the data signature function, they usually centrally store the RSA private key in a single storage medium and perform access control through a conventional password authentication mechanism.
[0003] However, such a solution has significant security flaws: on the one hand, the centralized storage of keys is vulnerable to physical attacks (such as disassembly and side-channel attacks), resulting in key leakage; on the other hand, the static password authentication mechanism is easily brute-forced or subject to man-in-the-middle attacks, and there is a lack of an effective integrity verification mechanism during data transmission, making it possible for signature data to be tampered with or forged. These problems seriously threaten the security of payment transactions, and there is an urgent need for a solution that can provide multiple security guarantees in all aspects of key storage, authentication processes, and data transmission. Summary of the Invention
[0004] The present invention aims to solve the problem that existing POS machines have security risks such as centralized storage of keys being vulnerable to physical attacks, weak password authentication mechanisms, and insufficient data transmission integrity during data signature, resulting in a relatively high risk of key leakage and data tampering.
[0005] To solve the above technical problems, the technical solution adopted by the present invention is: a POS machine for data signature, including a card reader module, a security authentication module, a key synthesis module, a security chip module, and a communication interface module.
[0006] The card reader module is used to read the key components stored in at least two chip cards; the security authentication module is used to perform password authentication on the inserted chip card, and the password authentication includes scrambling the input password and interacting with the chip card through APDU instructions; the key synthesis module is used to generate a complete key by performing an exclusive OR operation on the at least two read key components and store the complete key in the key security protection area of the POS machine; the security chip module is used to perform integrity verification on the input data and complete data signature inside the security chip based on the complete key; the communication interface module is used to interact with external tools and transmit signature data and verification information through a predefined serial port protocol.
[0007] Among them, the key security protection area is configured with a physical anti-disassembly design and triggers the destruction of sensitive data when a physical attack is detected.
[0008] As a further improvement of the present invention, the key component is a component of the RSA private key, and the at least two chip cards are physically separated Card A and Card B, which store the first component and the second component of the RSA private key respectively.
[0009] As a further improvement of the present invention, the security authentication module further includes a password scrambling unit and an authentication interaction unit.
[0010] The password scrambling unit is used to dynamically scramble the password input by the operator according to a preset rule; the authentication interaction unit is used to interact with the chip card through APDU instructions to authorize the reading of the key component after the password verification is completed.
[0011] As a further improvement of the present invention, the serial port protocol of the communication interface module includes: a data block transmission mechanism, a checksum generation mechanism, and an error retransmission mechanism.
[0012] The data block transmission mechanism is used to transmit the data to be signed to the security chip module in blocks of a fixed length; the checksum generation mechanism is used to generate a data integrity checksum during the transmission process; the error retransmission mechanism is used to trigger a retransmission process when the data verification fails.
[0013] A storage medium includes at least two chip cards, each chip card stores a component of the RSA private key, and the components can be combined into a complete key through an exclusive OR operation; the chip card is configured to only allow the key component to be read after the password authentication is passed.
[0014] As a further improvement of the present invention, the chip card adopts hardware encryption technology and supports security features such as anti-tampering, anti-counterfeiting, and anti-illegal access.
[0015] A data signature tool includes a PC-side tool, a protocol parsing module, and a log recording module.
[0016] The PC-side tool is used to load the data to be signed and transmit it to the above-mentioned POS machine through the serial port protocol; the protocol parsing module is used to parse the signature data and the integrity check result returned by the POS machine; the log recording module is used to record the complete process of the signature operation and abnormal events.
[0017] As a further improvement of the present invention, the PC-side tool further includes a dynamic key injection unit and a permission management unit.
[0018] The dynamic key injection unit is used to update the key component to the key security protection area of the POS machine through a secure channel; the permission management unit is used to restrict the execution permission of the signature operation according to the operator's role.
[0019] A data signature method, applied to the above POS machine, includes the following steps:
[0020] S1: Insert the first chip card into the POS machine, read the first key component after completing authentication by entering the password;
[0021] S2: Replace it with the second chip card, repeat the authentication process to read the second key component;
[0022] S3: Perform an exclusive OR operation on the first key component and the second key component to generate a complete key and store it in the key security protection area;
[0023] S4: Receive the data to be signed transmitted by an external tool, and complete data verification and signature through the security chip module;
[0024] S5: Return the signature data to the external tool according to the serial port protocol.
[0025] As a further improvement of the present invention, the exclusive OR operation is completed within the security chip module of the POS machine, and the generated complete key only exists temporarily in the memory and is not written into the persistent storage device.
[0026] Advantages of the present invention: By storing the RSA private key separately in physically separated chip cards, combining dynamic out-of-order password authentication, key synthesis and in-chip signature mechanism, as well as integrity verification and error retransmission design of data transmission, the present invention realizes multiple security protections for the entire life cycle of the key (storage, authentication, use, transmission), significantly reduces the risks of physical attacks, password cracking and data tampering. At the same time, through the key temporary storage and physical anti-disassembly design, it ensures that sensitive information cannot be persistently retained and is difficult to be illegally obtained, thus comprehensively improving the security and reliability of data signature of the POS machine. Description of the Drawings
[0027] Figure 1 is a flow block diagram of a POS machine, a storage medium, and a tool for data signature according to the present invention;
[0028] Figure 2 is an interaction process diagram of a PC tool and a POS machine of a POS machine, a storage medium, and a tool for data signature according to the present invention. Detailed Embodiments
[0029] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application clearer, the following further describes the present application in detail with reference to the drawings and embodiments. It should be understood that the embodiments described herein are only used to explain the present application and are not used to limit the present application.
[0030] The present invention provides a POS machine for data signature, which includes a card reader module, a security authentication module, a key synthesis module, a security chip module, and a communication interface module. The card reader module is used to read the key components stored in at least two chip cards; the security authentication module is used to perform password authentication on the inserted chip card, and the password authentication includes scrambling the input password and interacting with the chip card through APDU instructions; the key synthesis module is used to generate a complete key by performing an exclusive OR operation on at least two read key components and store the complete key in the key security protection area of the POS machine; the security chip module is used to perform integrity verification on the input data and complete data signature inside the security chip based on the complete key; the communication interface module is used to interact with external tools and transmit signature data and verification information through a predefined serial port protocol. Among them, the key security protection area is configured with a physical anti-disassembly design and triggers the destruction of sensitive data when a physical attack is detected.
[0031] In the present invention, the key component is a component of the RSA private key, and at least two chip cards are physically separated card A and card B, which store the first component and the second component of the RSA private key respectively.
[0032] In the present invention, the security authentication module further includes a password scrambling unit and an authentication interaction unit. The password scrambling unit is used to dynamically scramble the password input by the operator according to a preset rule; the authentication interaction unit is used to interact with the chip card through APDU instructions and authorize the reading of the key component after the password verification is completed.
[0033] The serial port protocol of the communication interface module in the present invention includes: a data block transmission mechanism, a check code generation mechanism, and an error retransmission mechanism. The data block transmission mechanism is used to transmit the data to be signed to the security chip module in fixed-length blocks; the check code generation mechanism is used to generate a data integrity check code during the transmission process; the error retransmission mechanism is used to trigger a retransmission process when the data verification fails.
[0034] A storage medium includes at least two chip cards, each chip card stores a component of the RSA private key, and the components can be synthesized into a complete key through an exclusive OR operation; the chip card is configured to only allow the key component to be read after the password authentication is passed.
[0035] In the present invention, the chip card adopts hardware encryption technology and supports security features such as anti-tampering, anti-counterfeiting, and anti-illegal access.
[0036] A data signature tool includes a PC-side tool, a protocol parsing module, and a log recording module. The PC-side tool is used to load the data to be signed and transmit it to the above-mentioned POS machine through the serial port protocol; the protocol parsing module is used to parse the signature data and integrity verification results returned by the POS machine; the log recording module is used to record the complete process of the signature operation and abnormal events.
[0037] In the present invention, the PC - side tool further includes a dynamic key injection unit and a permission management unit. The dynamic key injection unit is used to update the key component to the key security protection area of the POS machine through a secure channel; the permission management unit is used to restrict the execution permission of the signature operation according to the operator's role.
[0038] A data signature method, applied to the above - mentioned POS machine, includes the following steps:
[0039] S1: Insert the first chip card into the POS machine, after inputting the password to complete the authentication, read the first key component;
[0040] S2: Replace it with the second chip card, repeat the authentication process to read the second key component;
[0041] S3: Perform an exclusive - OR operation on the first key component and the second key component to generate a complete key and store it in the key security protection area;
[0042] S4: Receive the data to be signed transmitted by an external tool, and complete data verification and signature through the secure chip module;
[0043] S5: Return the signed data to the external tool according to the serial port protocol.
[0044] In the present invention, the exclusive - OR operation is completed within the secure chip module of the POS machine, and the generated complete key only exists temporarily in the memory and is not written into the persistent storage device.
[0045] Embodiment 1 (a specific implementation of a POS machine and method for data signature):
[0046] Taking a certain financial payment scenario as an example, this embodiment details the implementation process and technical effects of the present invention.
[0047] Step 1: Storage of key components and initialization of chip cards
[0048] Generate an RSA private key, and split it into two components (component one and component two), which are respectively stored in physically separated Card A and Card B.
[0049] Set independent access passwords for Card A and Card B respectively, and encrypt and store the key components through hardware encryption technology (such as the SM4 algorithm) to ensure that the chip cards have the capabilities of anti - tampering, anti - forgery, and anti - illegal access.
[0050] Step 2: Key synthesis and security authentication
[0051] The operator inserts card A into the card reader module of the POS machine, and the POS machine starts the password authentication process through the security authentication module: (1) The operator enters the password of card A into the POS machine, and the password scrambling unit dynamically scrambles the password according to preset rules (such as randomly replacing the order of input characters). (2) The security authentication module sends the scrambled password to card A through the APDU instruction, and card A decrypts and verifies the correctness of the password. (3) If the authentication is successful, the card reader module reads the key component 1 stored in card A and temporarily stores it in the memory of the POS machine.
[0052] Remove card A, insert card B, repeat the above password authentication process, and read key component 2.
[0053] The key synthesis module performs an XOR operation on component one and component two in the security chip module to generate a complete RSA private key and temporarily stores it in the key security protection zone. The key security protection zone adopts a physical anti-disassembly design (such as encapsulating epoxy resin). If a physical attack (such as drilling, high temperature) is detected, the sensitive data will be immediately triggered to self-destruct.
[0054] Step 3: Data signing and transmission
[0055] The PC-side tool sends the data to be signed (such as transaction message) to the POS machine via the serial port protocol.
[0056] (1) The communication interface module adopts a data block transmission mechanism to transmit data in blocks of fixed length (such as 1024 bytes) to the security chip module. (2) A checksum (such as CRC32) is added to each block of data. The security chip module verifies the data integrity. If the check fails, the error retransmission mechanism is triggered to retransmit the data.
[0057] The security chip module uses the temporarily stored complete key to perform a signing operation on the data. The signing process is completed entirely inside the security chip, and the key and intermediate calculation results are not exposed to the external environment.
[0058] After the signature is completed, the communication interface module returns the signature data to the PC tool through the serial port protocol, and the protocol parsing module parses the signature result and records the log.
[0059] Step 4: Dynamic key update and permission management
[0060] The administrator generates new key components through the dynamic key injection unit of the PC tool and transmits them to the POS machine through an encrypted channel (such as the TLS protocol) to update the key components in the key security protection zone.
[0061] The authority management unit limits the execution authority of the signature operation according to the operator role (such as ordinary operator, administrator), for example, only allowing the administrator to update the key component.
[0062] Verification of Technical Effects
[0063] (1) Key security: The physical separation storage and dynamic synthesis mechanism of key components prevent the exposure of the complete key even if a single chip card is leaked.
[0064] (2) Resistance to brute force cracking: The dynamic disordered password authentication significantly increases the difficulty of password guessing. Combined with the encrypted interaction of APDU instructions, it effectively resists man-in-the-middle attacks.
[0065] (3) Guarantee of data integrity: The block transfer and checksum mechanism ensure that the data is not tampered with during the transmission process, and the error retransmission mechanism improves the transmission reliability.
[0066] (4) Resistance to physical attacks: The self-destruction design of the key security protection area and the hardware encryption characteristics of the chip card effectively prevent physical disassembly and side-channel attacks.
[0067] Example 1 (Practical Application of Storage Medium and Tools):
[0068] In this example, a certain bank uses the storage media (Card A and Card B) and data signature tools of the present invention for cross-border payment services with high security levels.
[0069] (1) Key management: Card A and Card B are respectively kept by two authorized personnel, and the key is only synthesized by inserting into the POS machine during transactions, avoiding the risk of centralized key storage.
[0070] (2) Log traceability: The log recording module completely records the time, operator, data hash value, and abnormal events (such as authentication failures) of each signature operation, supporting post-event auditing and responsibility tracing.
[0071] (3) Emergency response: After a physical attack attempt triggers the self-destruction of the key, the administrator quickly updates the key components through the dynamic key injection unit to restore system operation and ensure business continuity.
[0072] This example verifies the significant advantages of the present invention in key storage, authentication process, data transmission, and anti-attack capabilities through a specific application scenario, providing a highly secure and reliable data signature solution for the financial payment field.
[0073] In summary, a POS machine, storage medium, and tool for data signature according to the present invention not only improve the security of data signature but also enhance the reliability and flexibility of the system. By implementing the present invention, financial institutions and other industries that require highly secure data signatures can significantly reduce the risks of key leakage and data tampering, while ensuring the integrity and traceability of signature operations. In addition, the dynamic key update mechanism and permission management function of the present invention provide a strong guarantee for the long-term secure operation and maintenance of the system. Therefore, the present invention has broad application prospects and important practical values.
[0074] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.
Claims
1. A POS machine for digital signature, characterized in that: Including card reader module, security authentication module, key synthesis module, security chip module, communication interface module, The card reader module is used to read the key components stored in at least two chip cards; the security authentication module is used to perform password authentication on the inserted chip card, and the password authentication includes interacting with the chip card through APDU instructions after scrambling the input password; the key synthesis module is used to generate a complete key through an XOR operation of the at least two key components read, and store the complete key in the key security protection zone of the POS machine; the security chip module is used to perform integrity verification on the input data, and complete the data signature inside the security chip based on the complete key; the communication interface module is used to interact with external tools and transmit signature data and verification information through a predefined serial port protocol; The key security protection zone is configured as a physical anti-disassembly design and triggers the destruction of sensitive data when a physical attack is detected.
2. A POS machine for data signature according to claim 1, characterized in that: The key components are components of an RSA private key, and the at least two chip cards are physically separated card A and card B, which respectively store a first component and a second component of the RSA private key.
3. A POS machine for data signature according to claim 1, characterized in that: The security authentication module further includes a password scrambling unit and an authentication interaction unit. The password scrambling unit is used to dynamically scramble the password input by the operator according to preset rules; the authentication interaction unit is used to interact with the chip card through APDU instructions and authorize the reading of the key component after completing the password verification.
4. A POS machine for data signature according to claim 1, characterized in that: The serial port protocol of the communication interface module includes: data block transmission mechanism, check code generation mechanism, error retransmission mechanism, The data block transmission mechanism is used to transmit the data to be signed in blocks of fixed length to the security chip module; the verification code generation mechanism is used to generate a data integrity verification code during the transmission process; and the error retransmission mechanism is used to trigger the retransmission process when the data verification fails.
5. A storage medium, characterized in that: It comprises at least two chip cards, each chip card stores a component of an RSA private key, and the components can be combined into a complete key through an exclusive OR operation; the chip card is configured to only allow authorized reading of the key component after password authentication is passed.
6. A storage medium according to claim 5, characterized in that: The chip card adopts hardware encryption technology and supports security features of anti-tampering, anti-counterfeiting and anti-illegal access.
7. A data signature tool, characterized in that: Including PC tools, protocol analysis module, and log recording module. The PC-side tool is used to load the data to be signed and transmit it to the POS machine as described in any one of claims 1-4 through the serial port protocol; the protocol parsing module is used to parse the signature data and integrity verification results returned by the POS machine; the log recording module is used to record the complete process and abnormal events of the signature operation.
8. A data signature tool according to claim 7, characterized in that: The PC-side tool further includes a dynamic key injection unit and a permission management unit. The dynamic key injection unit is used to update the key component to the key security protection zone of the POS machine through a secure channel; The authority management unit is used to limit the execution authority of the signature operation according to the operator role.
9. A data signature method, applied to a POS machine as claimed in any one of claims 1 to 4, characterized in that: The following steps are involved: S1: insert the first chip card into the POS machine, enter the password to complete the authentication and then read the first key component; S2: Replace with a second chip card and repeat the authentication process to read the second key component; S3: Perform an XOR operation on the first key component and the second key component to generate a complete key and store it in a key security protection zone; S4: receiving the data to be signed transmitted by the external tool, and completing the data verification and signing through the security chip module; S5: Return the signature data to the external tool according to the serial port protocol.
10. A data signature method according to claim 9, characterized in that: The XOR operation is completed in the security chip module of the POS machine, and the generated complete key only exists temporarily in the memory and is not written to the persistent storage device.