Device safety protection structure
By setting up an invisible and easily damaged wiring structure on the device and covering it with synthetic resin, the reverse engineering problem of FPGA and ROM devices is solved, and low-cost and high-resistance safety protection is achieved, and it is suitable for a variety of devices.
Patent Information
- Application Number
- CN202380092497.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2023-01-30
- Filing Date
- 2023-03-13
- Publication Date
- 2025-09-02
AI Technical Summary
The existing FPGA and ROM devices are easily reverse engineered to analyze, resulting in illegal acquisition of circuit wiring information and operation signal information, and the existing encryption technology is costly and poorly versatile.
A wiring structure with inherent characteristics is provided on the device, and the wiring position is covered with synthetic resin, so that the wiring position is invisible and vulnerable to damage. The device can only work when the wiring structure is not damaged, and security protection is achieved in combination with existing encryption technology.
It realizes low-cost, high-resistance reverse engineering safety protection, is suitable for a variety of devices, and does not require expensive pre-process processes, with flexibility and high versatility.
Smart Images
Figure CN120584346A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a device security protection structure that can prevent the illegal acquisition of working signal information or circuit wiring information through action analysis of a device installed on a substrate, thereby improving reverse engineering resistance. The device is, for example, a field programmable gate array (FPGA) as an integrated circuit that can be programmed by the user (for circuit wiring information), or a ROM that stores the circuit wiring information. Background Art
[0002] For example, an FPGA, a device mounted on a substrate, is an integrated circuit that generates a desired logic circuit by programming and inputting circuit wiring information, such as the positional information and wiring information of the components that make up the circuit. Specifically, for example, one such device includes a standard chip pre-arranged with multiple general-purpose logic circuits in a grid pattern. Users program the FPGA with the specified circuit wiring information required to implement the desired integrated circuit and input this program. This allows the general-purpose logic circuits to be connected, generating a logic circuit with the specified function. This device enables rapid device design and manufacture, making it highly advantageous for device development.
[0003] Furthermore, for example, in the case of an SRAM-type FPGA, the circuit wiring information required to obtain the desired integrated circuit is programmed, and the program is saved in an internally provided SRAM area, and actions are performed according to the program. However, since the circuit wiring information needs to be maintained even when the power is cut off, a non-volatile memory (ROM) is prepared externally, and the circuit wiring information is automatically loaded from the ROM to the FPGA when the power is turned on, so that the FPGA can operate.
[0004] That is, such an FPGA is a device that can generate the following desired integrated circuit. When the integrated circuit starts working, in order to achieve the desired function, the circuit wiring information is loaded from the ROM and written into the SRAM within the FPGA, thereby controlling the switch matrix, setting the function of the logic circuit block, and performing complex logical operations in sequence.
[0005] However, as mentioned above, existing FPGAs use a ROM that pre-stores circuit wiring information, and the circuit wiring information is loaded from the ROM when the power is turned on for use. However, the contents of the ROM can be easily read by a third party by using a ROM writer, etc., and the functions of the FPGA can be illegally used using such a copied ROM.
[0006] Therefore, in order to prevent illegal acquisition of circuit wiring information through internal analysis of devices such as FPGAs and ROMs mounted on substrates and to improve reverse engineering resistance, devices incorporating advanced encryption technology into the FPGAs and ROMs have been developed.
[0007] For example, a device has been developed that not only encrypts ROM data so that the internal data cannot be accessed, but also encrypts the FPGA's unique ID as a key, preventing the circuit wiring information from being expanded even when connected to other FPGAs.
[0008] On the other hand, even if the data is encrypted in this way, there is a concern that the action signal information and circuit wiring information can be illegally obtained by performing action analysis on the action signal and its operation. In order to prevent this concern and further improve the reverse engineering resistance, more expensive front-end processes are required, which increases the cost. Therefore, the security function of such FPGA is still insufficient, and it is not a technology that can be retrofitted to existing devices (such as such FPGA), and its versatility is also poor. Summary of the Invention
[0009] Problems to be solved by the invention
[0010] The purpose of the present invention is to provide a revolutionary device security protection structure with extremely excellent practicality. Its conversion concept solves the security problems existing in such installed devices such as FPGAs through technology that can be implemented at a low price. It can achieve extremely high reverse engineering resistance with low-cost installation technology. In addition, it is a technology that can also perform post-processing on existing devices. It is also highly versatile and can flexibly cope with and protect multiple devices, making it easy to implement in society.
[0011] Means for solving problems
[0012] The gist of the present invention will be described with reference to the accompanying drawings.
[0013] The present invention relates to a device safety protection structure, characterized in that a wiring structure 4 for safety with inherent characteristics is provided on the upper part of a device 2 mounted on a substrate 1 using wiring 3 or passive or active elements connected by wiring. The device 2 and the wiring structure 4 are covered with a synthetic resin 5, and the wiring position of the wiring structure 4 cannot be visually confirmed from the outside due to the covering synthetic resin 5. The device 2 cannot be disassembled or the operation of the device 2 cannot be analyzed and measured from the outside unless the wiring structure 4 is damaged. The wiring structure 4 is configured so that the acquisition of the inherent characteristics of the wiring 3 or the passive or active elements connected by wiring, or the acquisition of the combination of the inherent characteristics of the wiring structure 4 and the characteristics of the device 2, becomes an operating condition of the device 2. The device 2 has the following safety function: when the wiring structure 4 is damaged or removed, the device 2 does not operate and operation analysis cannot be performed.
[0014] Furthermore, the device security protection structure according to Technical Solution 1 is characterized in that the device 2 is an FPGA or a ROM in which the circuit wiring information of the FPGA is written, and the FPGA is an integrated circuit in which the user can program the circuit wiring information.
[0015] Furthermore, the device safety protection structure according to Technical Solution 1 is characterized in that it is constructed to have the following safety function: when the device 2 starts to work, if the wiring structure 4 is damaged or removed and the inherent characteristics cannot be obtained, the device 2 does not work, the working analysis of the device 2 cannot be performed, and the working signal information or circuit wiring information of the device 2 cannot be obtained.
[0016] Furthermore, the device safety protection structure according to technical solution 1 is characterized in that the wiring structure 4 is constructed by the wiring 3 or the passive components or active components that are wired around the upper part of the device 2, is covered with the synthetic resin 5 and integrated with the device 2, and is constructed to use the signal output from the specified terminals of the wiring 3 or the passive components or the active components or the combination of signals output from different terminals as the inherent characteristics, and the acquisition of the inherent characteristics or the acquisition of the combination of the inherent characteristics of the wiring structure 4 and the characteristics of the device 2 becomes the working condition of the device 2.
[0017] Furthermore, the device safety protection structure according to Technical Solution 1 is characterized in that the wiring structure 4 is constructed to surround the upper part of the device 2 vertically and horizontally, and the wiring is repeated in a wavy line shape with a height difference of 50 μm or more.
[0018] Furthermore, the device safety protection structure according to technical solution 1 is characterized in that the wiring 3 of the wiring structure 4 is a structure in which the wiring is carried out vertically and horizontally around the upper part of the device 2, and is covered by the synthetic resin 5 so that the wiring position or the passive components or the active components wired out cannot be visually confirmed from the outside, and is set to a material that can be damaged by removing the chemical of the synthetic resin 5.
[0019] Effects of the Invention
[0020] The present invention is constructed as described above, and thus becomes an extremely practical and epoch-making device safety protection structure. It can achieve extremely high reverse engineering resistance with low-cost installation technology. In addition, it is a technology that can also perform post-processing on existing devices. It is also highly versatile and can flexibly cope with and protect multiple devices, making social implementation easier. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 It is an operation explanation diagram of this embodiment.
[0022] Figure 2 It is an explanatory cross-sectional view showing the schematic structure of this embodiment.
[0023] Figure 3 This is an explanatory perspective view of the installation state before protection using synthetic resin in this embodiment.
[0024] Figure 4 This is a perspective view illustrating the installation state of the embodiment after protection using synthetic resin. DETAILED DESCRIPTION
[0025] The preferred embodiments of the present invention will be briefly described with reference to the accompanying drawings to illustrate the effects of the present invention.
[0026] The present invention adopts a structure in which a wiring structure 4 for realizing a safety function is provided on the upper part of a device 2 mounted on a substrate 1, and is configured such that the acquisition of the aforementioned inherent characteristics of the wiring structure 4 based on the wiring 3 or the passive elements or active elements wired out, or the acquisition of the inherent characteristics of the wiring structure 4 in combination with the characteristics of the aforementioned device 2 becomes the working condition of the device 2.
[0027] Therefore, the configuration is such that when the wiring structure 4 is damaged or removed, the device 2 does not operate, and operation analysis cannot be performed.
[0028] Furthermore, in the present invention, the device 2 and the wiring structure 4 are covered with synthetic resin 5 to integrate them, and the synthetic resin 5 is made, for example, an opaque resin, thereby making it impossible to visually confirm the wiring position of the wiring structure 4 or the passive elements or active elements from the outside.
[0029] That is, in the present invention, a safety protection structure is implemented for the device 2 to be protected. The safety protection structure uses a wiring structure 4 that realizes the safety function and a synthetic resin 5 covering the wiring structure 4 for protection. The wiring structure 4 is composed of wiring 3 or passive components or active components connected with the wiring. Therefore, unless the wiring 3 or the passive components or active components of the aforementioned wiring structure 4 are damaged, the protected device 2 cannot be disassembled or the action of the protected device 2 cannot be analyzed and measured from the outside.
[0030] Specifically, for example, when one wants to physically remove the synthetic resin 5, since the wiring position or passive components or active components of the wiring structure 4 cannot be seen, if the wiring 3 is arranged vertically and horizontally, or is arranged in a wavy manner with ups and downs, at least a portion of the wiring 3 will almost certainly be damaged and broken.
[0031] Furthermore, for example, when chemical dissolution removal is attempted using chemicals, if the material of the wiring 3 is set to a material that reacts with the synthetic resin 5, at least a portion of the wiring 3 will almost certainly be damaged and disconnected.
[0032] Furthermore, for example, even if a measuring piece is inserted from the outside while the synthetic resin 5 is kept intact to perform an operation analysis of the device 2, since the wiring position or the passive or active components cannot be seen, if the wiring 3 is arranged vertically and horizontally, or is arranged in a wavy manner with up and down projections, at least a portion of the wiring 3 will almost certainly be damaged and broken.
[0033] Therefore, if someone attempts to access the device 2 for internal analysis and operational analysis, the wiring 3 or passive or active components will almost certainly be damaged, making it impossible to illegally perform operational analysis. Specifically, unsealing analysis is difficult, and the device is resistant to both physical and chemical lineage analysis. By employing a security structure with such security functions, operational analysis is impossible. Furthermore, by combining this with existing encryption technology, for example, a security structure with extremely high resistance to reverse engineering can be achieved through simple wiring installation and molding of synthetic resin 5.
[0034] To further explain, in the present invention, the inherent characteristics of the wiring structure 4 based on the wiring 3 are used as inherent characteristics, for example, the combination of signals output from the wiring 3 or the specified terminals or different terminals of the passive element or active element is used as the inherent characteristic, and the inherent characteristics are used as the inherent working key for, for example, starting the device 2 and expanding the program of circuit wiring information. That is, the inherent characteristics of the wiring structure 4 based on the wiring 3 or the passive element or active element wired out become the working conditions of the device 2. Therefore, unless the wiring structure 4 is damaged, the inherent characteristics cannot be obtained, so the device 2 does not work and the working analysis cannot be performed illegally. Therefore, as described above, a security protection structure with a security function with high resistance to reverse engineering can be easily constructed.
[0035] That is, in the present invention, when the device 2 starts to work, if the wiring 3 of the aforementioned wiring structure 4 or the passive components or active components connected by the wiring are damaged or removed and the aforementioned inherent characteristics cannot be obtained, the aforementioned device 2 does not work, and therefore the operation analysis of the device 2 cannot be performed, and the operation signal information and circuit wiring information of the aforementioned device cannot be obtained. Therefore, as described above, a safety protection structure with a safety function that is highly resistant to reverse engineering can be easily constructed.
[0036] Therefore, the present invention is a groundbreaking device security protection structure that does not require further expensive encryption processing to improve reverse engineering resistance in order to prevent illegal action analysis. It can achieve extremely high reverse engineering resistance with low-cost installation technology. In addition, it is a technology that can perform post-processing on existing devices, has high versatility, can flexibly cope with and protect multiple devices, and is easy to implement in society.
[0037] Example
[0038] Specific embodiments of the present invention will be described with reference to the accompanying drawings.
[0039] In this embodiment, a safety wiring structure 4 with inherent characteristics based on the wiring 3 is stacked and arranged above two devices 2: an FPGA (an integrated circuit whose circuit wiring information can be programmed by a user) and a ROM (a programmable ROM) on which the FPGA's circuit wiring information is written. Furthermore, the wiring structure 4 is covered from above with an opaque synthetic resin 5 to form an integrated structure. The wiring positions of the wiring structure 4 are thus obscured from view from the outside by the opaque synthetic resin 5. This prevents the device 2 from being removed from the substrate 1 or from being analyzed and measured from the outside unless the wiring structure 4 is damaged. Alternatively, multiple devices 2 may be assembled and covered with the wiring structure 4 and synthetic resin 5, or each device 2 to be protected may be covered separately. Furthermore, the devices 2 are not limited to FPGAs and ROMs; for example, a single-chip microcomputer or the like may be used as the device 2 and covered.
[0040] Furthermore, in this embodiment, the acquisition of the inherent characteristics of the wiring structure 4 based on the wiring 3, or the acquisition of the combination of the inherent characteristics of the wiring structure 4 and the characteristics of the device 2, becomes a condition for the operation of the device 2. This configuration provides a safety feature: if the wiring structure 4 is damaged or removed, the device 2 will not operate, and analysis of the operation of the device 2 will become impossible. Furthermore, in this embodiment, the inherent characteristics are acquired by combining the outputs between terminals at various locations on the wiring of the wiring structure 4, which is arranged in a concave and convex pattern on the upper portion of the device 2. However, the wiring structure 4 may be constructed not only from wiring but also from wiring combined with passive or active elements, and the inherent characteristics may be acquired by combining the outputs between these predetermined terminals.
[0041] Specifically, the data of the FPGA and ROM serving as the device 2 are encrypted and, as described above, covered with security protection having the aforementioned security function. The security function is configured such that when the device 2 starts working, if the aforementioned wiring structure 4 is damaged or removed and the aforementioned inherent characteristics cannot be obtained, the aforementioned device 2 does not work. If an action analysis of the aforementioned device 2 is desired, the protected wiring structure 4 will be damaged, causing the device 2 to not work, making it impossible to perform action analysis and illegally obtain action signal information and circuit wiring information.
[0042] To further explain, the wiring structure 4 of this embodiment is a structure for performing circuit wiring around the wiring 3 on the upper part of the device 2, and is constructed so as to use the signal output between specified terminals selected from multiple terminals of the wiring 3 or the combination of signals output from different terminals as the aforementioned inherent characteristics, and use the inherent characteristics as the working conditions of the aforementioned device 2 (the inherent working key at startup).
[0043] Specifically, as described above, the inherent characteristics of the wiring structure 4 based on the wiring 3 are used as inherent characteristics, for example, the combination of signals output from the specified terminals of the wiring 3 is used as the inherent characteristics, and the inherent characteristics are used as the inherent working key for the operation of the device 2. As long as the wiring structure 4 is damaged, the inherent characteristics cannot be obtained, and therefore the program of circuit wiring information cannot be loaded from the ROM, so the device 2 does not work, and even if the program is erased in the middle of the operation, for example, it cannot work again.
[0044] For example, when the FPGA is activated, if the inherent characteristics of the wiring structure 4 can be detected and acquired, the user program in the ROM is loaded into the FPGA and expanded, thereby initiating operation. Furthermore, after the user program is expanded, the initial startup program is deleted from the FPGA. Furthermore, even while the program is running, the status of the wiring structure 4 is periodically checked to monitor for abnormalities. Furthermore, although this depends on the settings, if an abnormality occurs, the function may be limited, the status may be maintained constant, the program may be deleted, or operation may be disabled.
[0045] Furthermore, in this embodiment, in addition to this security function, the data in the device 2 is encrypted using existing encryption technology, making it impossible to illegally obtain circuit wiring information and the like through internal analysis.
[0046] Therefore, through this safety protection structure, if its protection is damaged, that is, the wiring 3 of the wiring structure 4 is broken, at least the device 2 will not work, and will stop working or cannot work again, so illegal action analysis cannot be performed, and a safety function with extremely high resistance to reverse engineering will be exerted.
[0047] The wiring structure 4 of this embodiment is connected to the device 2 and is wired vertically and horizontally around the device 2 above it. It has a plurality of output terminals and is wired in a wavy line shape with repeated unevenness having a height difference of 50 μm or more.
[0048] Furthermore, in this embodiment, in order to facilitate such wiring, the synthetic resin 5 is used to form bulges 6 at intervals on the upper part of the device 2, and wiring is routed around the bulges 6, thereby making it easy to wire in a wavy shape with the desired height difference.
[0049] Furthermore, the wiring 3 is a structure of vertical and horizontal wiring on the upper part of the aforementioned device 2, and is covered by the aforementioned opaque synthetic resin 5, making it impossible to visually confirm the wiring position from the outside, but the wiring 3 is formed of a material that can be damaged by chemicals that can dissolve and remove the synthetic resin 5.
[0050] Therefore, for example, when one wants to physically remove the synthetic resin 5 bit by bit, such as by mechanically grinding it off, since the wiring position of the wiring structure 4 cannot be seen, and the wiring 3 is not only arranged vertically and horizontally, but also arranged in a wavy manner with up and down bumps, at least a portion of the wiring 3 will definitely be damaged and broken.
[0051] Furthermore, even if chemical dissolution and removal are attempted using chemicals, as described above, since the wiring 3 is made of a material that reacts with the synthetic resin 5 , at least a portion of the wiring 3 is inevitably damaged and disconnected.
[0052] Moreover, even if one wants to insert a measuring piece from the outside while keeping the synthetic resin 5 intact to perform an operation analysis of the device 2, it is difficult to see the wiring position, and the wiring 3 is not only arranged vertically and horizontally, but also arranged in a wavy manner with up and down bumps. Therefore, it is almost certain that the measuring piece will damage at least a part of the wiring 3 and cause it to break.
[0053] Therefore, if one wants to approach the device 2 to perform action analysis for internal analysis, the wiring 3 will almost certainly be damaged. Therefore, the following device protection structure can be easily implemented. The device protection structure makes action analysis impossible through the installation of the wiring 3 and the molding of the synthetic resin 5, and has a safety function with high resistance to reverse engineering.
[0054] Furthermore, to further explain, in this embodiment, if the synthetic resin 5 is removed or a measuring piece is inserted to perform motion analysis, the user program cannot be loaded as described above and the device will not work. Even if an abnormality is detected due to damage to the wiring 3 during operation, initialization is performed and the program is erased. Furthermore, even if the ROM is replaced, it cannot be started using the encryption of the ID inherent in the FPGA. Furthermore, as described above, abnormal voltage monitoring is performed through the function of the FPGA, and if an abnormality occurs, the device stops working. Therefore, replacement work cannot be performed and motion analysis cannot be performed, thereby achieving further improvement in reverse engineering resistance.
[0055] Furthermore, by providing a plurality of terminals in the wiring structure 4 as described above, the unique work key for operation can be easily changed to various values by selecting combinations of the terminals, thereby achieving high reverse engineering resistance.
[0056] Therefore, in this embodiment, instead of using expensive pre-processes for making motion analysis impossible to perform advanced encryption processing, a revolutionary device security protection structure that is versatile, inexpensive, and highly resistant to reverse engineering can be provided through inexpensive installation technology. The device security protection structure can install the wiring structure 4 on the device 2, and can integrate them by post-installation molding of synthetic resin 5 to provide security protection with a security function. The wiring structure 4 generates an inherent key for starting work that can be detected and obtained by startup.
[0057] Furthermore, it can be realized with a small number of devices, has a high degree of freedom in wiring formation, can be flexibly formed in a plurality of devices 2, and can easily change and set various unique operation keys as operation conditions.
[0058] The present invention is not limited to the present embodiment, and the specific structure of each component can be designed as appropriate.
[0059] Description of labels
[0060] 1: Substrate; 2: Device; 3: Wiring; 4: Wiring structure; 5: Synthetic resin; 6: Protrusion.
Claims
1. A device safety protection structure, characterized in that: On the upper part of the device mounted on the substrate, a wiring structure with inherent safety characteristics is provided by wiring or passive or active elements derived from the wiring. The device and the wiring structure are covered with a synthetic resin, and the wiring position of the wiring structure cannot be visually confirmed from the outside due to the covering synthetic resin. The device is configured so that the device cannot be disassembled or its operation cannot be analyzed and measured from the outside unless the wiring structure is damaged. The structure is such that the acquisition of the inherent characteristics of the wiring structure based on the wiring or the passive elements or the active elements routed out, or the acquisition of the combination of the inherent characteristics of the wiring structure and the characteristics of the device becomes the working condition of the device, and has the following safety function: when the wiring structure is damaged or removed, the device does not work and action analysis cannot be performed.
2. The device safety protection structure according to claim 1, characterized in that: The device is an FPGA or a ROM in which circuit wiring information of the FPGA is written. The FPGA is an integrated circuit whose circuit wiring information can be programmed by a user.
3. The device safety protection structure according to claim 1, characterized in that: The structure is such that it has the following safety function: when the device starts to work, if the wiring structure is damaged or removed and the inherent characteristics cannot be obtained, the device will not work, the device operation analysis cannot be performed, and the device operation signal information or circuit wiring information cannot be obtained.
4. The device safety protection structure according to claim 1, characterized in that: The wiring structure is constructed by the wiring or the passive elements or active elements that are wired around the upper part of the device, is covered with the synthetic resin and integrated with the device, and is constructed so that the signal output from the specified terminals of the wiring or the passive elements or the active elements or the combination of signals output from different terminals is used as the inherent characteristic. The acquisition of the inherent characteristic or the acquisition of the combination of the inherent characteristic of the wiring structure and the characteristics of the device becomes the working condition of the device.
5. The device safety protection structure according to claim 1, characterized in that: The wiring structure is configured to surround the upper portion of the device in both vertical and horizontal directions, and is wired in a wavy line shape with repeated concavities and convexities having a height difference of 50 μm or more.
6. The device safety protection structure according to claim 1, characterized in that: The wiring of the wiring structure is a structure in which the wiring is carried out vertically and horizontally around the upper part of the device, and is covered with the synthetic resin so that the wiring position or the passive components or active components wired out cannot be visually confirmed from the outside, and is set to a material that can be damaged by the chemical used to remove the synthetic resin.