TW515948B - Content securing method of non-volatile storage device and architecture thereof - Google Patents

Abstract

The present invention relates to a content securing method of non-volatile storage device and an architecture thereof. Firstly, programs stored in a flash memory are block-based. Based on the blocks, rotation is carried out or, in other words, stored addresses are scrambled, to store the data in the original address into a new address after rotation. A random number generator is applied to generate a random number reading sequence for data reading and the read data includes correct data and some dummy data. Then, all the dummy read data are filtered before carrying out address rotation to recover and restore the original data. So, by means of address scrambling, data are directly read into useless data to make data stealing, modification, and alteration of illegal intruders difficult. Thus, protection is provided to flash memory.

Description

515948 V. Description of the invention (1) Summary of the invention: The present invention relates to a non-volatile storage device content confidentiality method and 3 j means: a kind of use of address disruption to make data messy, so that non- ^ Useless to protect flash memory 'stolen, modified, changed. Technical background description: As shown in the first figure, the microcontroller unit (MClKnucro controller unit) in the existing computer architecture is the main body of the architecture, and its external memory (multiple flash memory 1 ()) is used. It is stored in the flash memory i. However, the current encryption / decryption protection system does not provide any protection for the quick girlfriend body 10, so it is stored in the flash = body 10 ^ program The content will be difficult to protect. Those skilled in cryptographic cracking technology can easily read the clear text stored in flash memory 丨 0. For example, the program stored in flash memory 10 is to detect the user ’s password and verify the user ’s body. All the resources of the system will be completely disclosed as such, or use software (such as SOFT IN CIRCUIT EMULATOR, SOFT ICE) to crack and modify the program, so that the intruder can directly read the flash memory if the password is unknown. It can achieve the purpose of stealing resources by entering the system, making the system security at risk. For another example, mobile phone manufacturers usually use DSPs to develop their own programs. These programs are In the mobile phone function, and does not receive important information people want to know information such as capacity, are entitled to the protection of intellectual property rights, but the set is stored in flash memory 1〇 Shique these important data is tantamount to public. In other

515948

In other words, in the encryption / decryption system that provides system protection, the network memory is suspected to be a security loophole: "The solution before the project (as shown in the second picture) is to change the micro: early Wu MCU" flash memory The body 10 is placed in the same IC20 and accessed through the 2 data line, and the program to be executed in the flash memory is determined to be modified and cracked. However, although this method can hardly be cracked, the production of the flash memory 10 and the logic elements of the microcontroller unit MCU belongs to a different process, which will cause a significant increase in process costs. Therefore, it is not an ideal solution. This is why the present invention is mainly based on the fact that the flash memory is read / injected at the _ second boot or load mode, and these two situations do not occur often, so = use Xixu's logic design and Specially designed software achieves flash memory protection. According to the foregoing, the main purpose of the present invention is to provide a method and structure for protecting the content of a volatile storage device. The method is mainly to block the program with an appropriate size and use the concepts of address scrambling and random numbers (rand0In). In order to make the data arrangement a new combination with the change of the address, the original data cannot be reorganized without the restoration method, so as to provide the security of flash memory protection without the cost of a large process. The structure design and technical principle of the present invention will be described in detail below _ and explained with reference to the accompanying drawings to further understand the features of the present invention, of which:

515948 V. Description of the invention (3) The first diagram is a schematic diagram of an existing computer architecture; the second diagram is a schematic diagram of a current structure in which a microcontroller unit and a flash memory are placed in the same IC; the third diagram is a system of the present invention Schematic diagram; The fourth diagram is the internal architecture diagram of the memory data security chip of the third diagram; the fifth diagram is the schematic diagram of the data before and after the rotation of the invention; the sixth diagram is the flowchart of the write operation steps of the invention: The diagram is a flowchart of the reading operation steps of the present invention: The eighth diagram is a schematic diagram of the architecture of the second embodiment of the present invention; the ninth diagram is a diagram before and after the data of the eighth diagram A is rotated. Call for illustrations:

1 0 Flash memory 20 1C 3 0 Memory data security chip 31 Address disturber 32 Random number generator 33 Decoder 3 4 Buffer g 35 Key 4 0 Chip 41 Register 42 Programmable read-only memory 43 Random number generator

515948

As shown in the third figure, the microcontroller unit or the MR of the present invention reads or writes data to the flash memory 10, first, 30: Γ =: or restore. The memory information is stored in the security chip 30. The P structure is shown in the fourth figure; it includes:-Bit Island Scrambler 31 'is a block program that rotates, disrupts the original address into a set of new addresses for the original data storage, and uses the new address Flash memory 10;

-Random number generator 32, which generates a set of random sequences, so that the data in flash memory 10 is read in this order; Understanding the code generator 33, which filters the address data read in random numbers in order Data, and invert the program block to obtain the original data and address for the microcontroller unit MCU (or DSP) to execute. In the following, the MCU unit MCU writes and reads the flash memory 10 as two parts: [Writing procedure] ---- Can be regarded as the encoding action of the data: The software will The program to be executed is block-based. Generally, 8x8 is used as a block basis, and these blocks are used as a basis to rotate 'that is, the stored address is scrambling through the address disruptor 31. ), So that the data in the original address is stored in the new address after rotation. In order to simplify the description, a 4 X 4 block is used for explanation below. The left side of the fifth circle is a squared raw data. The address 8Oh is stored as 0011, the address 81h is stored as 1011, 82h is stored as 1100, and 83h is stored as 1010. Rotate (rotate 90 degrees to the right in this embodiment, not limited

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The formula box is shown on the right side of the fifth figure. The new address «, = ΐ is 1110, 81,11 and the stored one is changed to 0100, η 1 is changed to 1011, 83, and h is changed to _. For the ^ 'x box, you can find the rightmost vertical data in the right figure, that is, $: rh data, and so on. Therefore, it is obvious that all 1s in the same address have been disrupted. These data are stored in the flash memory 101. The intruder does not know that the data has been disrupted, it directly from the flash memory 10 The reader is completely different from the original data. The writing operation can be summarized as the flow chart of the sixth figure: Step a · Program block step; Step b. Rotate the box to disturb the original data address to generate a new address step; Step c • Store the original data in a new position Address; step d · write to the flash memory 10 according to the new address. [Reading procedure] It can be regarded as the decoding operation of the data. A random number generator 32 (random number generator) is used to randomly generate a random sequence. Stored in a buffer 34 (can be SRAM). These read data include the data written in the aforementioned writing procedure and dummy data. Therefore, the redundant data must be filtered out when the data is restored. , Find the required relevant address, filter out the redundant address data through the decoder 33, and then reverse this box to obtain the original data and address for use by the microcontroller unit MCU or DSP. Since the flash memory 10 is externally connected to the MCU or DSP of the microcontroller unit, the illegal intruder can also read these data, but through random numbers

515948 V. Description of the invention (6) The random number reading order provided by the generator 32 will read the required and redundant data, and the ordering and combination that cannot be understood, so it is extremely difficult to crack the read data content . The reading operation can be summarized in the flowchart of the seventh figure: Step a. Use the random number generator 32 to generate a group of random number reading sequence steps; Step b. Read from the flash memory 10 in the order of step a. Steps of outputting and temporarily storing in the buffer 34; Step c. Filtering the temporary storage value of the buffer 34 to remove redundant data; Step d. Reverse rotating the block to obtain the original address and data. In addition, in the reading process, since each memory data security chip 3 0 uses a single key 3 5 (key), that is, each system has its single address mapping sequence, so it can be filtered What address information is redundant and what address information is useful. And this spare key 35 can be stored in the memory data security chip 30 or a smart card. [Second Embodiment] Since the address is linearly increased, in this simple change, illegal intruders are very easy to find the address of the program they need. Therefore, in this embodiment, the original randomness in the chip 40 is used. The code randomly swaps real addresses to generate a new set of random addresses to store data and make a simple change. As shown in the eighth figure, the program loaded by the microcontroller unit MCU is read into the chip 40 with the byte (BYTE) as an early bit, and stored in the register 41 in the chip 40. This chip 40 is also provided with Programmable read-only memory

515948 V. Description of the invention (7) 'One' One ---- the body 42 (PROM) or a smaller flash memory. As mentioned above, it is difficult and expensive to include flash memory 10 in the chip, but it is very easy to make a programmable read-only memory 42. The random code generated by the random number generator 43 is burned into the programmable read-only memory 42 and a conversion table (not shown) is constructed to control the correspondence between the original address and the rotated address. The data in the address is written according to the random code, and then the flash memory 10 is rotated and written into the random address. The data is directly read by the address fragmentation, which makes it useless, making it difficult for illegal intruders to steal. , Modify, and update the information, and provide protection for the Flash memory 10. In addition, since the random number generator 43 randomly generates the conversion tables generated on the actually manufactured wafer 40, they are not identical, so it is not limited to the only way to cover the original data in the flash memory. In addition, the original address can be complemented first and then randomly swapped to increase the difficulty of cracking. " The following uses a 4-bit address as an illustration (as in the ninth figure), as ~ A0 is the original address, m3 ~ m0 is the random code address, and the arrow shown in the figure is the random swap of the two. relationship. For example, A3 is 0011, A2 is 〇〇〇〇, A1 * 000 1, and 〇 is 〇〇〇〇, the original address is complemented operation 'm3 = A2, m2 = A 0, ml = A3, m〇 = A1, m3 is 0110, m2 is ooio, mi is oiii, and ο is 〇〇11, as & the new address of the flash memory 10 is stored, and the original data is more based on the above operation. Capture. When reading, the conversion table stored in the programmable read-only memory 42 (PROM) is restored to the original data.

515948 V. Description of the invention (8) In addition, 'Since the computer is turned on, the material is read, and then read in order = read the first-pen resource-random number generator 43 in the data ::: increase the difficulty of cracking, It is possible to insert unwanted data, and the computer will return the required Gongke with two ^ ^^^^ ^ Gore also reads the inserted data, forming a situation of false reading, so it is not ^^ β ^ ^ 卜 x This non-intruder will not be able to know the correct address sequence, and will not be able to access the correct data. In summary, in the non-volatile storage device provided by the present invention, m ?: address scrambling and e-), the data arrangement of the block processing will generate a new one as the address changes. Combination, and cannot restore the original data without the restoration method, and propose effective solutions and countermeasures for the lack of flash memory that cannot be protected by the current encryption / decryption protection system, which has indeed met the application requirements for the creation patent. The Bureau has conducted detailed examination and granted patents to benefit the people and benefit the country and the people. ~ Only the methods, techniques, diagrams, programs, or control methods described above are just one of the preferred embodiments of the present invention; for example, all equivalent changes or modifications or extraction of some functions made according to the technology of the scope of patent application of the present invention The same production should still fall within the scope of the patent right of the present invention; when the scope of implementation of the present invention cannot be limited accordingly.

Claims (1)

515948 6. Application scope d. Reverse rotation block to obtain the original address and data; 5. Kinds of non-volatile storage and confidentiality structure of the content, mainly in fast material, single unit (or DSP) and flash There is one memory data and two J pieces in the memory, which are used to add and write data to and from the flash memory, including the in-address disturber, which rotates the block program, and starts the address disruption. Create a new set of addresses for storing the original data, and insert them into the flash memory according to the address; Depending on the well-being, a fast-random number generator is generated to generate a random sequence so that the fast data is read out in this order; 〇u Internal tribute: solution: device Zhao ,: address data read in random order filters out excess resources and reverses the square block to obtain the original data and address and the two units (or DSP) execute.叩 仏 From the controller 6. The non-volatile storage architecture described in item 5 of the scope of the patent application, wherein the memory data security chip further includes a single device, which is a single address mapping sequence, and Filter out extra data. 7. · A non-volatile storage device content confidentiality method, especially the special read-only memory (PR0M), or the characteristics of: the use of a random number generator to generate random read-only memory Construct a conversion table 'to control the correspondence between the original and converted addresses, write the data in the original address according to a random code', and then rotate the random address into the flash memory. 8. Content protection of non-volatile storage device as described in item 7 of the scope of patent application Page 13 515948 VI. Patent application range secret method, which includes the steps of performing a complement operation on the original address before the address is randomly swapped. 9. The non-volatile storage device content confidentiality method described in item 7 of the scope of patent application, wherein when reading, a random number generator can be used to 'randomly insert unnecessary lean materials' among the required data. The computer is also the same For these inserted lean material reads, a false read situation is formed, so that illegal intruders will not be able to know the correct address sequence, and will not be able to retrieve the correct data. # Page 14