WO2021129557A1

WO2021129557A1 - File encryption method and related apparatus

Info

Publication number: WO2021129557A1
Application number: PCT/CN2020/137923
Authority: WO
Inventors: 杨涛; 张广宇; 王海军
Original assignee: 华为技术有限公司
Priority date: 2019-12-23
Filing date: 2020-12-21
Publication date: 2021-07-01
Also published as: CN113094718A

Abstract

A file encryption apparatus, comprising: a processor, a universal flash storage (UFS) controller coupled with the processor, and a memory coupled with the UFS controller. The processor is used for sending a first request to the UFS controller (S301), wherein the first request is used for requesting the storage of a target file. The UFS controller is used for: acquiring a target random number corresponding to the target file (S302); generating, according to the target random number and a pre-stored first key, a second key corresponding to the target file (S304); encrypting the target file by means of the second key, so as to obtain an encrypted target file (S305); and storing the encrypted target file in the memory. The memory is used for storing the encrypted target file (S306). By means of the apparatus provided in a first aspect, in the case of a high storage efficiency, the mode of encryption of one file with one key can still be ensured, which improves the encryption level of a file.

Description

File encryption method and related device

This application claims the priority of a Chinese patent application filed with the Chinese Patent Office on December 23, 2019, the application number is 201911343064.0, and the application name is "a file encryption method and related device", the entire content of which is incorporated into this application by reference in.

Technical field

This application relates to the field of information technology, and in particular to a file encryption method and related devices.

Background technique

With the popularization of smart terminals, smart terminals have become a necessity in people's daily life, but at the same time, the security problems of smart terminals have become increasingly prominent: such as information leakage, fraud, and Trojan horse viruses. Therefore, users pay more and more attention to the safety of smart terminals. For information security in smart terminals, current smart terminal storage systems generally use full disk encryption or file encryption to protect file information in smart terminals. For example: the file encryption method based on the existing Universal Flash Storage (UFS) protocol uses the limited key file encryption (total files limited keys) method, which is determined by the trusted execution environment in the processor ( Trust Execute Environment (TEE) configures 32 sets of initial keys ClassKey at one time, and then encrypts the files in the smart terminal with the initial keys. However, this method will not refresh and configure the new Class Key in the encryption process of other files in the future. Therefore, the keys used in the encryption process of this file encryption method are all fixed 32 sets of initial keys. To the requirement of one file and one key, the encryption level is lower. If you want to implement a file with a key, you need to switch the TEE side to configure a new Class Key before switching to the file management module in the processor to encrypt the file before encrypting the file. It will lead to frequent interactions between TEE and file management modules, making the actual storage efficiency extremely low.

Therefore, how to ensure the storage efficiency and encryption level of file encryption at the same time when the smart terminal encrypts and saves the file is a problem to be solved urgently.

Summary of the invention

The embodiments of the present application provide a file encryption method and related equipment, which guarantee the storage efficiency and encryption level of file encryption at the same time under the condition of UFS transmission protocol.

In the first aspect, an embodiment of the present application provides a file encryption device, including: a processor and a universal flash memory host UFS controller coupled with the above-mentioned processor; the above-mentioned processor is configured to send a first request to the above-mentioned UFS controller, The first request is used to request storage of the target file; the UFS controller is used to: obtain the target random number corresponding to the target file; generate the target file corresponding to the target file according to the target random number and the pre-stored first key The second key; the target file is encrypted by the second key to obtain the encrypted target file.

With the device provided in the first aspect, when the UFS controller encrypts different files, it can first generate the encryption of different files according to the same initial key (first key) and the random number corresponding to each file in the different files. Key (second key), and then encrypt different files according to the key corresponding to each file in the different files, so that the encryption key used by each file in the file encryption process is different , Where each file has a unique random number corresponding to it. It is understandable that because the keys used for file encryption are different between different files, it can be ensured that after the encrypted storage of the file, the encrypted file is not easily hacked, resulting in information leakage. This encryption method can greatly improve the file’s security. Encryption level. Secondly, in each file encryption process, different random numbers can be used to generate the file key based on the same initial key, which can avoid the TEE refreshing the initial file too frequently in order to increase the encryption level of the file. The key makes the encrypted storage of files inefficient and wastes resources. Therefore, the method provided by the first aspect can ensure the storage efficiency and encryption level of file encryption at the same time based on the UFS transmission protocol.

In a possible implementation manner, the above UFS controller is also used to: obtain the above target file. To implement the embodiments of this application, the target file can be obtained first before encrypting the target file. The target file may be obtained by the UFS controller actively after the file management system of the processor generates the file, or it may be file management of the processor. After the system generates the file, the UFS controller passively receives it. For example: the file management module directly sends the target file to the UFS controller after creating the target file; another example: the file management module stores the target file in the temporary memory after creating the target file, and the storage address It is sent to the UFS controller together with the first request, and the UFS controller obtains the above-mentioned target file according to the storage address.

In a possible implementation manner, the UFS controller is further configured to: obtain the descriptor of the first request corresponding to the target file, the descriptor includes the data unit number DUN; the UFS controller is specifically used for: The target file is divided into multiple file data blocks; starting from a file data block corresponding to the DUN among the multiple file data blocks, the multiple file data blocks are sequentially encrypted according to the second key to obtain the encryption After the target file. To implement the embodiment of this application, in the process of encrypting the target file by the UFS controller, the initial encryption object of the target file (that is, the file data block corresponding to the above DUN among the multiple file data blocks) needs to be determined according to the DUN in the descriptor, and then Controlling the target file to perform an encrypted storage operation can improve the encryption level of the file while ensuring the storage efficiency of the file encryption. Second, divide the target file into multiple file data blocks, and then use a block encryption algorithm to encrypt the target file, which also improves the encryption level of file encryption. For example, the block length of the block encryption algorithm can be 128 bits, and the key length can be 128 bits, 192 bits, or 256 bits of the advanced encryption standard encryption algorithm.

In a possible implementation manner, the above-mentioned processor is further configured to generate the above-mentioned target random number and the above-mentioned descriptor of the above-mentioned target file when the above-mentioned target file is created. In implementing the embodiment of the present application, when the file management module in the processor creates the target file, it can generate the target random number uniquely corresponding to the target file and the first request descriptor corresponding to the target file. Therefore, the random numbers and descriptors corresponding to different files are different, which ensures the encryption level of file encryption, increases the difficulty of cracking the encrypted target file, and reduces the risk of target file leakage.

In a possible implementation manner, the aforementioned device further includes a dynamic random access memory coupled to the processor and the aforementioned UFS controller respectively; the aforementioned processor is further configured to: extend the aforementioned descriptor according to the aforementioned target random number to obtain The extended descriptor, the extended descriptor includes the target random number and the DUN; the extended descriptor is sent to the dynamic random access memory; the UFS controller is specifically configured to: according to the first request, from the above The above-mentioned extended descriptor is acquired in the dynamic random access memory; the above-mentioned target random number and the above-mentioned DUN are acquired according to the above-mentioned extended descriptor. To implement the embodiment of the present application, the UFS controller can obtain the target random number by adding the target random number to the descriptor when generating the target random number and the descriptor, that is, by extending the descriptor, The expanded descriptor may carry the target random number and be stored in the dynamic random access memory. The UFS controller obtains the target random number by obtaining the expanded descriptor. After obtaining the target random number, the key is generated according to the target random number. The method of obtaining the key also ensures that only the target random number will appear in the file management module (ie, software level) of the processor, and the root secret The key (ie, the second key) is derived from hardware logic, and will not be perceived and acquired by software, so the security factor of the key will be improved.

In a possible implementation manner, the aforementioned device further includes a dynamic random access memory coupled to the processor and the aforementioned UFS controller respectively; the aforementioned processor is further configured to: send the aforementioned target random number to the aforementioned dynamic random access memory; The descriptor is expanded according to the storage address of the target random number and the data length of the target random number to obtain an expanded descriptor. The expanded descriptor includes the storage address of the target random number and the data length of the target random number. And the aforementioned DUN; sending the aforementioned expanded descriptor to the aforementioned dynamic random access memory; the aforementioned UFS controller is specifically configured to: obtain the aforementioned expanded descriptor from the aforementioned dynamic random access memory according to the aforementioned first request; and determine the aforementioned expanded descriptor The storage address of the target random number in the descriptor, and the target random number is obtained according to the storage address of the target random number; and the DUN is obtained according to the expanded descriptor. In the case of implementing the embodiments of this application based on the JESD223D protocol, the UFS controller can obtain the target random number by obtaining the storage address in the extended descriptor. After obtaining the target random number, the key is generated according to the target random number. The method of obtaining the key also ensures that only the target random number will appear in the file management module (ie, software level) of the processor, and the root secret The key (that is, the second key) is derived from the hardware logic and will not be perceived and acquired by the software. Therefore, the security factor of the key will be improved, and the risk of cracking the file after a criminal steals the key is greatly reduced.

In a possible implementation manner, the aforementioned device further includes a dynamic random access memory coupled with the processor and the aforementioned UFS controller respectively; the aforementioned processor is further configured to: send the aforementioned descriptor to the aforementioned dynamic random access memory; The address register in the UFS controller sends the storage address of the target random number; the UFS controller is specifically used to: obtain the descriptor from the dynamic random access memory according to the first request; store according to the address register in the UFS controller The storage address of the above-mentioned target random number to obtain the above-mentioned target random number. To implement the embodiment of this application, the processor directly sends the target random number to the UFS controller, and the UFS controller generates the encrypted key according to the target random number. This UFS controller can directly obtain the storage address of the target random number. The method to obtain the target random number also ensures that only the target random number will appear in the processor (that is, at the software level), and the root key (second key) is derived from the hardware logic and will not be obtained by the software. Perception and acquisition will increase the security factor of the key used to encrypt the target file, greatly reduce the risk of cracking the file after a criminal steals the key, improve the security level, and the method of obtaining the target random number will not affect The storage efficiency of target files saves resources.

In a possible implementation manner, the above-mentioned device further includes: a random number generator coupled with the above-mentioned UFS controller, the above-mentioned random number generator is used to generate variable parameters, and the above-mentioned variable parameters are used to generate the above-mentioned second key; the above-mentioned UFS The controller is specifically configured to: generate a third key according to the target random number and the variable parameter, wherein the variable parameter includes a first variable and a second variable, and the first variable is used to identify the position of the second key. Width, the second variable is a random number with a preset fixed bit width or a number with a preset fixed bit width that identifies the file attribute of the target file, wherein the preset fixed bit width of the second variable is determined by the third key The bit width of is determined; the second key is generated by a derived algorithm according to the third key and the pre-stored first key. The implementation of the embodiment of this application can generate a third key according to the target random number, the first variable parameter, and the second variable parameter. The third key uniquely corresponds to the target file, and then it is based on the third key and the pre-stored first secret. The second key generated by the key is also unique. Therefore, the encryption method of one file one key greatly improves the encryption level of the file. At the same time, the second key is derived from the hardware logic according to the first key, and the software cannot perceive and obtain it, which reduces the risk of file decryption after the key is stolen by criminals.

In a possible implementation manner, the target random number is a random number of file attributes, and the bit width of the target random number includes one of the following bit widths: 128 bits, 192 bits, 256 bits, and 512 bits. The implementation of the embodiment of the present application can encrypt the target file by using random numbers with different digits. It is understandable that the target random number is to encrypt the target file. The encryption algorithm used in the encryption process for different digits of random numbers may be the same or different. When the digits of the random number are higher, the corresponding The encryption algorithm may be more complicated, that is, the calculation process is more cumbersome, the higher the security performance, and the more conducive to file protection.

In a possible implementation manner, the above-mentioned device further includes a memory coupled with the above-mentioned UFS controller; the above-mentioned UFS controller is used to store the above-mentioned encrypted target file in the above-mentioned memory; the above-mentioned memory is used to store the above-mentioned encrypted target file The target file. To implement the embodiments of this application, the encrypted target file can be stored in a memory. The memory can be a solid-state drive of a smart terminal, UFS Flash (UFS Flash), solid-state memory, etc., which can effectively save the target after the smart terminal encrypts the file. file.

In a possible implementation manner, the above-mentioned processor is further configured to: send a second request to the above-mentioned UFS controller, and the above-mentioned second request is used to request to read the above-mentioned encrypted target file; the above-mentioned UFS controller, It is also used for: obtaining the second key corresponding to the target file according to the second request, decrypting the encrypted target file according to the second key, and reading it. By implementing the embodiments of the present application, when the UFS controller receives a request to read an encrypted file, it can decrypt and read the encrypted file according to the read request to obtain the unique second key used when encrypting the file. The target file can only be read when there is a second key, which is conducive to the confidentiality of the target file. At the same time, the second key is derived from hardware logic and will not be stored in the UFS controller. Access, reducing the risk of being stolen by criminals.

In the second aspect, an embodiment of the present application provides a file encryption method, including: sending a first request to a universal flash memory host UFS controller through a processor, the first request is used to request storage of a target file; The device obtains the target random number corresponding to the target file; the UFS controller generates the second key corresponding to the target file according to the target random number and the pre-stored first key; the UFS controller generates the second key corresponding to the target file according to the second secret key. The key encrypts the above target file to obtain the encrypted target file.

In a possible implementation manner, the foregoing method further includes: obtaining the foregoing target file through the foregoing UFS controller.

In a possible implementation manner, the above method further includes: obtaining, through the UFS controller, the descriptor of the first request corresponding to the target file, and the descriptor includes the data unit number DUN; The second key encrypts the target file to obtain the encrypted target file, including: dividing the target file into a plurality of file data blocks by the UFS controller; from the plurality of file data blocks by the UFS controller Starting from a file data block corresponding to the DUN, the multiple file data blocks are sequentially encrypted according to the second key to obtain an encrypted target file.

In a possible implementation manner, the above method further includes: when the target file is created by the processor, generating the target random number and the descriptor of the target file.

In a possible implementation manner, the above method further includes: extending the descriptor according to the target random number by the processor to obtain an extended descriptor, and the extended descriptor includes the target random number and the DUN. Sending the expanded descriptor to the dynamic random access memory through the processor; acquiring the target random number corresponding to the target file through the UFS controller includes: using the UFS controller according to the first request, from the dynamic random number The aforementioned extended descriptor is acquired in the memory; the aforementioned target random number and the aforementioned DUN are acquired according to the aforementioned expanded descriptor through the aforementioned UFS controller.

In a possible implementation manner, the above method further includes: sending the target random number to the dynamic random access memory through the processor; and using the processor to base the descriptor on the storage address of the target random number and the value of the target random number. The data length is expanded to obtain an expanded descriptor. The expanded descriptor includes the storage address of the target random number, the data length of the target random number, and the DUN; and the processor sends the expanded descriptor to the dynamic random access memory through the processor. The above-mentioned obtaining the target random number corresponding to the above-mentioned target file through the above-mentioned UFS controller includes: obtaining the above-mentioned extended descriptor from the above-mentioned dynamic random access memory according to the above-mentioned first request through the above-mentioned UFS controller; through the above-mentioned UFS The controller determines the storage address of the target random number in the expanded descriptor, and obtains the target random number according to the storage address of the target random number; the UFS controller obtains the first request corresponding to the target file The descriptor includes: obtaining the DUN according to the expanded descriptor through the UFS controller.

In a possible implementation manner, the above method further includes: sending the descriptor to the dynamic random access memory through the processor; sending the storage address of the target random number to the address register in the UFS controller through the processor; Obtaining the target random number corresponding to the target file through the UFS controller includes: acquiring the descriptor from the dynamic random access memory through the UFS controller according to the first request; and acquiring the descriptor from the dynamic random access memory through the UFS controller according to the UFS controller. The storage address of the target random number stored in the address register is used to obtain the target random number.

In a possible implementation manner, the above method further includes: generating a variable parameter by a random number generator, the variable parameter is used to generate the second key; the UFS controller according to the target random number and pre-stored The first key to generate the second key corresponding to the target file includes: generating a third key according to the target random number and the variable parameter by the UFS controller, wherein the variable parameter includes a first variable and a second variable , The first variable is used to identify the bit width of the second key, the second variable is a random number with a preset fixed bit width or a number with a preset fixed bit width that identifies the file attribute of the target file, wherein the first The preset fixed bit width of the two variables is determined by the bit width of the third key; the UFS controller generates the second key through a derived algorithm according to the third key and the pre-stored first key.

In a possible implementation manner, the target random number is a random number of file attributes, and the bit width of the target random number includes one of the following bit widths: 128 bits, 192 bits, 256 bits, and 512 bits.

In a possible implementation manner, the above method further includes: storing the encrypted target file in a memory through the UFS controller; and storing the encrypted target file in the memory.

In a possible implementation manner, the above method further includes: sending a second request to the UFS controller through the processor, the second request being used to request to read the encrypted target file; and controlling through the UFS According to the second request, the device obtains the second key corresponding to the target file, decrypts the encrypted target file according to the second key, and reads it.

In a third aspect, an embodiment of the present application provides a file encryption device, including: a first sending unit, configured to send a first request to a universal flash memory host UFS controller through a processor, and the first request is used to request a target file The first acquisition unit is used to obtain the target random number corresponding to the target file through the UFS controller; the key unit is used to generate the target random number and the pre-stored first key through the UFS controller The second key corresponding to the target file; an encryption unit for encrypting the target file according to the second key by the UFS controller to obtain an encrypted target file.

In a possible implementation manner, the above-mentioned apparatus further includes: a second obtaining unit, configured to obtain the above-mentioned target file through the above-mentioned UFS controller.

In a possible implementation manner, the above-mentioned apparatus further includes: a third obtaining unit, configured to obtain, through the above-mentioned UFS controller, the descriptor of the above-mentioned first request corresponding to the above-mentioned target file, and the above-mentioned descriptor includes the data unit number DUN; The encryption unit is specifically configured to: divide the target file into multiple file data blocks through the UFS controller; start from a file data block corresponding to the DUN among the multiple file data blocks through the UFS controller, and in turn according to the above The second key encrypts the multiple file data blocks to obtain the encrypted target file.

In a possible implementation manner, the above-mentioned apparatus further includes: a first generating unit, configured to generate the above-mentioned target random number and the above-mentioned descriptor of the above-mentioned target file when the above-mentioned processor is used to create the above-mentioned target file.

In a possible implementation manner, the above-mentioned apparatus further includes: a first extension unit, configured to extend the above-mentioned descriptor according to the above-mentioned target random number by the above-mentioned processor to obtain an extended descriptor, and the above-mentioned extended descriptor includes The above-mentioned target random number and the above-mentioned DUN; a second sending unit, configured to send the above-mentioned extended descriptor to a dynamic random access memory through the above-mentioned processor; and the above-mentioned first acquiring unit, specifically configured to: according to the above-mentioned first The request is to obtain the expanded descriptor from the dynamic random access memory; the UFS controller obtains the target random number and the DUN according to the expanded descriptor.

In a possible implementation manner, the above-mentioned apparatus further includes: a third sending unit, configured to send the above-mentioned target random number to the dynamic random access memory through the above-mentioned processor; and a second extension unit, configured to send the above-mentioned descriptor through the above-mentioned processor According to the storage address of the target random number and the data length extension of the target random number, an expanded descriptor is obtained. The expanded descriptor includes the storage address of the target random number, the data length of the target random number, and the DUN The third sending unit is configured to send the expanded descriptor to the dynamic random access memory through the above-mentioned processor; the above-mentioned first acquiring unit is specifically configured to: according to the above-mentioned first request through the above-mentioned UFS controller, from the above-mentioned dynamic random access The expanded descriptor is acquired in the memory; the storage address of the target random number in the expanded descriptor is determined by the UFS controller, and the target random number is acquired according to the storage address of the target random number; the third The obtaining unit is specifically configured to obtain the DUN according to the expanded descriptor through the UFS controller.

In a possible implementation manner, the above-mentioned device further includes: a fourth sending unit, configured to send the above-mentioned descriptor to the dynamic random access memory through the above-mentioned processor; and send the above-mentioned target to the address register in the UFS controller through the above-mentioned processor. The storage address of the random number; the first obtaining unit is specifically configured to: obtain the descriptor from the dynamic random access memory through the UFS controller according to the first request; use the UFS controller according to the address in the UFS controller The storage address of the target random number stored in the register is used to obtain the target random number.

In a possible implementation manner, the above-mentioned device further includes: a second generation unit, configured to generate a variable parameter through a random number generator, the above-mentioned variable parameter is used to generate the above-mentioned second key; the above-mentioned key unit is specifically used to: The UFS controller generates a third key according to the target random number and the variable parameter, wherein the variable parameter includes a first variable and a second variable, and the first variable is used to identify the bit width of the second key, The second variable is a random number with a preset fixed bit width or a number that identifies the file attribute of the target file. The preset fixed bit width of the second variable is determined by the bit width of the third key. Wide determination; the UFS controller generates the second key through a derived algorithm according to the third key and the pre-stored first key.

In a possible implementation manner, the above-mentioned device further includes: a first storage unit, configured to store the encrypted target file in a memory through the above UFS controller; and a second storage unit, configured to store the above-mentioned encrypted target file through the above-mentioned memory. After the target file.

In a possible implementation manner, the foregoing apparatus further includes: a fifth sending unit, configured to send a second request to the UFS controller through the foregoing processor, and the foregoing second request is used to request to perform the encryption on the encrypted target file. Read; a decryption unit for obtaining the second key corresponding to the target file according to the second request through the UFS controller, and decrypting the encrypted target file according to the second key before reading.

In a fourth aspect, the embodiments of the present application provide a chip system that includes any device for supporting file encryption involved in the first aspect mentioned above. The chip system may be composed of a chip, or may include a chip and Other discrete devices.

In the fifth aspect, an embodiment of the present application provides a computer storage medium for storing computer software instructions used for the file encryption device provided in the first aspect, which includes a program for executing the program designed in the first aspect. .

In a sixth aspect, the embodiments of the present application provide a computer program, the computer program includes instructions, when the computer program is executed by a computer, the computer can execute the process executed by the file encryption apparatus in the first aspect.

Description of the drawings

In order to more clearly describe the technical solutions in the embodiments of the present application or the background art, the following will describe the drawings that need to be used in the embodiments of the present application or the background art.

FIG. 1A is a schematic diagram of an application scenario when an audio recording file is encrypted and saved according to an embodiment of the present application.

Fig. 1B is a schematic diagram of an application scenario for saving downloaded files provided by an embodiment of the present application.

FIG. 1C is a schematic diagram of a file encryption architecture based on a UFS controller provided by an embodiment of the present application.

FIG. 1D is a schematic diagram of another file encryption architecture based on a UFS controller provided by an embodiment of the present application.

Figure 2 is a schematic diagram of a file encryption device provided by an embodiment of the present application.

Fig. 3 is a schematic flowchart of a file encryption method provided by an embodiment of the present application.

Fig. 4 is a schematic structural diagram of a transmission request descriptor UTRD provided by an embodiment of the present application.

FIG. 5 is a schematic structural diagram of an extended descriptor UTRD provided by an embodiment of the present application.

Fig. 6 is a schematic diagram of a file encryption algorithm framework applied in a UFS controller provided by an embodiment of the present application.

Fig. 7 is a schematic structural diagram of another file encryption device provided by an embodiment of the present application.

FIG. 8 is a schematic structural diagram of another file encryption device provided by an embodiment of the present application.

Detailed ways

The embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application.

The terms "first", "second", "third", and "fourth" in the specification and claims of this application and the drawings are used to distinguish different objects, not to describe a specific order . In addition, the terms "including" and "having" and any variations of them are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes unlisted steps or units, or optionally also includes Other steps or units inherent to these processes, methods, products or equipment.

The reference to "embodiments" herein means that a specific feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art clearly and implicitly understand that the embodiments described herein can be combined with other embodiments.

The terms "component", "module", "system", etc. used in this specification are used to denote computer-related entities, hardware, firmware, a combination of hardware and software, software, or software in execution. For example, the component may be, but is not limited to, a process, a processor, an object, an executable file, an execution thread, a program, and/or a computer running on a processor. Through the illustration, both the application running on the computing device and the computing device can be components. One or more components may reside in processes and/or threads of execution, and components may be located on one computer and/or distributed among two or more computers. In addition, these components can be executed from various computer readable media having various data structures stored thereon. The component may be based on, for example, data having one or more data packets (for example, data from two components interacting with another component in a local system, a distributed system, and/or a network, for example, the Internet that interacts with other systems through signals) Signals are communicated through local and/or remote processes.

First of all, some terms in this application are explained to facilitate the understanding of those skilled in the art.

(1) Universal Flash Storage (UFS) is a flash storage specification designed for use in electronic products such as digital cameras and smart terminals. While providing high data transmission speed and stability, it can also reduce user confusion about various memory card formats on the market and the use of different memory card adapters. Among them, UFS Flash (UFS Flash) is one of the mainstream storage media in the mobile phone system, which can be the storage medium of the mobile phone chip system. The exchange of data between the mobile phone SOC chip and UFS Flash is based on the mipi ufs protocol.

(2) Solid State Drive (SSD), or solid state drive, is a hard drive made of an array of solid-state electronic storage chips. The SSD is composed of a control unit and a storage unit (Flash chip, DRAM chip). Its chip has a wide operating temperature range and has a wide range of applications. There are usually two types of storage media for solid-state hard drives, one is to use flash memory (Flash chip) as the storage medium, and the other is to use DRAM as the storage medium.

(3) Advanced Encryption Standard (AES), the AES encryption process operates on a 4×4 byte matrix, this matrix is also called "state", and its initial value is a plaintext block (The size of an element in the matrix is one Byte in the plaintext block). (The Rijndael encryption method supports larger blocks, and the number of matrix rows can be increased according to the situation.) When encrypting, each round of AES encryption cycle (except the last round) includes 4 steps, namely AddRoundKey, SubBytes, ShiftRows, And MixColumns.

(4) Key Derivation Functions (KDF), which can also be called key derivation functions. The function of the key derivation function is to derive key data from a shared secret bit string. In the key agreement process, the key derivation function acts on the shared secret bit string obtained by the key exchange to generate the required session key or further encrypt the required key data.

(5) Central Processing Unit, CPU for short, is the computing core and control core of a computer, and the final execution unit for information processing and program operation. The CPU includes arithmetic logic components, register components, and control components, and has functions such as processing instructions, executing operations, controlling time, and processing data.

(6) Trusted execution environment (TEE), which is an area on the processor CPU. The function of this area is to provide a safer space for data and code execution, and to ensure their confidentiality and integrity.

(7) Register is a very important storage unit in integrated circuits, usually composed of flip-flops. The register is an integral part of the central processing unit. Registers are high-speed storage components with limited storage capacity. They can be used to temporarily store instructions, data, and addresses. In the control unit of the central processing unit, the registers included are the instruction register (IR) and the program counter (PC). In the arithmetic and logic components of the central processing unit, the register has an accumulator (ACC).

(8) A physical block (block) is the smallest storage and processing unit in the database, and contains the header data or PL/SQL code of the block itself. The size of the block can be specified by selecting "Custom Installation" during installation. The size of the block is generally between hundreds of KB to several MB. Each block includes multiple pages, and the size of the page is generally 4KB Multiples of (such as 4KB or 16KB).

(9) Double-rate synchronous dynamic random access memory (Double Data Rate, DDR), so that the main steps of transmission and output of the specified address and data are executed independently, while keeping fully synchronized with the CPU; DDR uses DLL (Delay Locked Loop, extended Time-locked loop provides a data filtering signal) technology. When the data is valid, the storage controller can use this data filtering signal to accurately locate the data, output once every 16 times, and resynchronize the data from different memory modules.

(10) Dynamic Random Access Memory (DRAM) uses the amount of charge stored in a capacitor to represent 0 and 1. This is a binary bit (bit), the smallest unit of memory. That is, DRAM is the most common system memory. DRAM can only hold data for a short time. In order to retain data, DRAM uses capacitor storage, so it must be refreshed every certain period of time. If the memory cell is not refreshed, the stored information will be lost.

In order to facilitate the understanding of the embodiments of the present invention, the following exemplarily enumerate the application scenarios of the file encryption method in this application, which may include the following two scenarios:

Scenario 1: When using the smart terminal, the user can encrypt and save the generated related files.

When a user is using a smart terminal (such as a mobile phone), in order to better protect the privacy of the user when using the smart terminal, the files generated when the smart terminal is used (such as: game video when playing a game) Files, audio files recorded during phone calls, image files taken by the camera, text files when editing memos, browsing records when browsing the Internet, etc.) are encrypted and stored to prevent smart terminal information from being stolen by criminals and causing users Privacy leaked. For example: please refer to FIG. 1A, which is a schematic diagram of an application scenario when an encrypted recording file is saved according to an embodiment of the present application. As shown in Fig. 1A, when the user finishes using the recording function of the mobile phone, the smart terminal can encrypt the recorded audio file through the SOC chip, and then store it in the memory. Therefore, when the user uses the smart terminal, the related data generated by the user can be encrypted and stored to ensure that the user's privacy is not leaked.

Scenario 2: The user connects to the Internet through a smart terminal, and after downloading the relevant data file, the data file can be encrypted and saved.

When the user browses to the favorite pictures, videos, files, etc., when using the mobile phone to surf the Internet, the file can be encrypted and saved in the mobile phone, which not only can better store the file, but also prevent the leakage of private information. For example: please refer to Figure 1B, which is a schematic diagram of an application scenario for saving downloaded files provided by an embodiment of the present application. As shown in Figure 1B, after a user downloads a file online, he can control the encryption through the file control module and the UFS controller, and store it in the memory. The encrypted file greatly reduces the risk of the encrypted file being stolen. Therefore, when a user uses a smart terminal to download or receive a file sent by another smart terminal, the file is encrypted and stored, which can greatly avoid important information or privacy information leakage opportunities.

It is understandable that the above two application scenarios are only a few exemplary implementations in the embodiments of the present invention, and the application scenarios in the embodiments of the present invention include but are not limited to the above application scenarios. For example: encrypted storage of files received via Bluetooth, encrypted storage of system files generated after the smart terminal runs related applications, and so on.

Based on the corresponding application scenarios in this application, and in order to facilitate the understanding of the embodiments of the present invention, the following first describes one of the system architectures on which the embodiments of the present application are based. Please refer to Figure 1C. Figure 1C is a schematic diagram of a file encryption architecture based on a UFS controller provided by an embodiment of the present application. The architecture shown in Figure 1C is mainly based on an SOC chip and is described from the perspective of file encryption storage. In the application scenarios shown in the foregoing FIG. 1A and the foregoing FIG. 1B. The file encryption method based on the UFS controller proposed in this application can be applied to the system architecture. The system architecture includes a processor 101 and a universal flash storage host controller (Universal Flash Storage Host Controller, UFSHC) coupled with the processor 101, that is, the UFS controller 102, and may also include: and the UFS controller 102 coupled memory 103, Double Data Rate DRAM controller (DDRC) 104, where, if the encryption architecture is applied to smart terminals (such as mobile phones, tablet computers, etc.), UFS controller 102 is equivalent For the solid state disk (SSD) of the smart terminal, it can be understood that the solid state disk can be configured in different devices, and different devices correspond to different forms of master control. Not limited, such as servers or personal computers; the memory 103 is equivalent to UFS Flash (UFS Flash), solid-state memory, etc., used to store encrypted target files; the double-rate dynamic random storage controller 104 is used to control the intelligent terminal Temporary memory or running memory, such as Dynamic Random Access Memory (DRAM), Double Data Rate Synchronous Dynamic Random Access Memory (Double Data Rate, DDR), etc. Optionally, please refer to FIG. 1D. FIG. 1D is a schematic diagram of another file encryption architecture based on a UFS controller provided in an embodiment of the present application. On the basis of FIG. 1C, the file encryption architecture based on the UFS controller may further include a random number generator 105 coupled with the UFS controller 102. Take Fig. 1D taking the processor 101, the UFS controller 102, the double-rate dynamic random memory controller 104 and the random number generator 105 integrated inside the SOC chip as an example for illustration; alternatively, the UFS controller 102 can be independent of The processing device of the processor 101 is connected to the processor 101 and the memory 103 to perform operations such as file storage, file reading, and file encryption; and the double-rate dynamic random storage controller 103 can also be an independent storage device for Control the dynamic random access memory storage processor 101 to generate the target random number and descriptor of the target file, etc., which will not be repeated here.

Specifically, when the processor 101 creates a file, it can synchronously generate a target random number and a descriptor of the file, where the target random number (Meta Data) is randomly generated and has a random number with file attributes; the descriptor In this application, it can be understood as a UFS Transfer Request Descriptor (UTP Transfer Request Descriptor, UTRD). The processor is further configured to send a first request to the UFS controller, where the first request is used to request storage or encrypted storage of the target file.

After the UFS controller 102 receives the first request from the processor 101 for the target file, it can obtain the target random number of the target file corresponding to the first request according to the first request; and then according to the target random number and the pre-stored target random number. The first key generates the second key corresponding to the target file; then the target file is encrypted by the second key to obtain the encrypted target file; the encrypted target file is stored in the Memory.

The random number generator 105 coupled with the UFS controller 102 can generate variable parameters, and the variable parameters are used to generate a second key for file encryption. After using the second key to encrypt, the variable parameter, the target random number and the encrypted file can be stored in the memory 103 together. So that when the file is read, the second secret key is determined according to the variable parameter corresponding to the target file and the target random number, and then the same second secret key is used to decrypt and read the encrypted file. Among them, the random number generator 104 may be a true random number generator.

It is understandable that the specific file encryption scenario after the processor 101, the UFS controller 102 coupled to the processor 101, and the memory 103 coupled to the UFS controller 102 are configured are also applicable to the embodiments of the present application. The system architecture shown in the figure will not be repeated here.

It can also be understood that memory and dynamic random access memory are two different types of memory. The memory is used to store encrypted files. It is a memory that stores data for a long time, that is, the encrypted files stored in the smart terminal/system after the power is off. Will be lost, such as: the mobile phone memory in the mobile phone; and the dynamic random access memory is used to temporarily store the target file before encryption, used to store random numbers, descriptors, etc., and is the memory for storing data for a short time, that is, the smart terminal/system interrupt Temporary files, stored random numbers, descriptors, etc. stored in it will be lost after power-up, such as the running memory in the mobile phone.

It should be noted that, the processor 101, the UFS controller 102, and the double-rate dynamic random memory controller 104 may be integrated in one chip, or they may be integrated in different chips. The embodiment of this application does not make specific details about this limited.

It should also be noted that the file encryption system architecture shown in FIG. 1C and FIG. 1D are only some exemplary implementations in the embodiments of the present application. The file encryption system architecture in the embodiments of the present application includes but is not limited to the above file encryption system Architecture.

In combination with the system architecture shown in FIG. 1C and FIG. 1D, an embodiment of the present application also provides a diagram of a file encryption device applied to a smart phone terminal, which can be applied to the system architecture shown in FIG. 1D, please refer to FIG. 2, FIG. 2. It is a schematic diagram of a file encryption device provided by an embodiment of the present application. As shown in FIG. 2, the file encryption device 10 in the embodiment of the present application may include a processor 101, a UFS controller 102 coupled with the processor 101, a memory 103 coupled with the UFS controller 102, and the UFS A dynamic random access memory DRAM 113 coupled to the controller 102 and a double-rate dynamic random access memory controller 104 (DDRC), and a random number generator 105 coupled to the UFS controller 102. The built-in logic module of the processor 101 may include: a trusted execution environment (Trust Execute Environment, TEE) 211, a file management module 212, and so on. The built-in logic module of the UFS controller 102 may include: a key store (Key Store) 221, etc., the key store 221 is equivalent to the internal memory of the UFS controller, wherein the key store 221 may also include a storage target random The address register that stores the address of the number. The built-in logic module of the dynamic random access memory DRAM 113 may include a first storage module 231 and a second storage module 232. among them,

The TEE211 in the processor can be used to configure the first key in the file encryption process. For example, after the system of the smart terminal to which the file encryption device belongs is powered on or when the UFS controller is initialized, the trusted execution environment TEE configures the first key (Class Key) in the Key Store of the UFS controller. In general, there are only 32 sets of ClassKeys in the UFS controller. Therefore, one of the most efficient solutions can be to configure 32 sets of ClassKeys to the KeyStore of the UFS controller by the TEE at one time when the UFS controller is initialized.

The file management module 212 in the processor can create a target file for storage or reading, etc., and can also synchronously generate the target random number of the file and the transmission request descriptor UTRD when creating the target file for encrypted storage of the file And decrypted read.

The Key Store 221 in the UFS controller 102 is equivalent to the memory/register inside the UFS controller for storing the first key issued by the TEE in the processor. Wherein, in a possible implementation manner, the memory may also include an address register, which is used to store the storage address of the target random number, so that the UFS controller can directly obtain the target random number according to the storage address stored in the register. So that the target file is encrypted.

The first storage module 231 in the dynamic random access memory 113 may be used to store the target random number.

The second storage module 232 in the dynamic random access memory 113 may be used to store the transmission request descriptor UTRD. It can be understood that the first storage module 231 and the second storage module 232 may be different storage areas in the same dynamic random access memory, or may be two different dynamic random access memories, which are not specifically limited for comparison in the embodiments of the present application.

The random number generator 105 can generate variable parameters, the variable parameters including a first variable and a second variable, the first variable is used to identify the bit width of the second key, and the second variable is a preset A random number with a fixed bit width or a number with a preset fixed bit width identifying the file attribute of the target file, wherein the preset fixed bit width of the second variable is determined by the bit width of the third key; The second key is generated through a derived algorithm according to the third key and the pre-stored first key. Among them, the random number generator 105 may be a true random number generator.

It should also be noted that the structure of the file encryption device shown in FIG. 2 is only a partial exemplary implementation in the embodiments of the present application, and the structure of the file encryption device in the embodiments of the present application includes but is not limited to the above file encryption device structure.

Based on the system architecture provided in FIG. 1C and FIG. 1D and the structure of the file encryption device provided in FIG. 2, combined with the file encryption method provided in this application, the technical problems proposed in this application are specifically analyzed and resolved.

Referring to FIG. 3, FIG. 3 is a schematic flowchart of a file encryption method provided by an embodiment of the present application. The method can be applied to the file encryption system architecture shown in FIG. 1C and FIG. 1D and the file encryption device shown in FIG. 2 Among them, the file encryption device 10 shown in FIG. 2 can be used to support and execute steps S301 to S306 of the method flow shown in FIG. 3.

Step S301: Send a first request to the universal flash memory host UFS controller through the processor.

Specifically, the processor sends a first request to the universal flash memory host UFS controller, where the first request is used to request storage of the target file. It is understandable that the file management module in the processor may send a first request for storing the target file to the UFS controller. For example, the first request may be a UFS Transport Request (UFS Transport) in this application. Protocol Transfer Request), that is, UTP Transfer Request. Optionally, the first request may also be used to request encrypted storage of the target file.

Optionally, the target file is obtained through the UFS controller. It is understandable that after receiving the first request, the UFS controller can obtain the target file identified or carried in the first request to encrypt it. Among them, the way the UFS controller obtains the file may include: the UFS controller receives the target file sent by the file management module in the processor, for example: the file management module directly sends the target file to the UFS controller after creating the target file Or, the UFS controller then obtains the target file from the dynamic random access memory (ie, temporary memory) according to the first request sent by the file management module in the processor, where the dynamic random access memory can be used for temporary storage in the processor The target file created by the file management module of the file management module, for example: after the file management module creates the target file, it stores the target file in the dynamic random access memory, and sends the storage address to the UFS controller together with the first request. The UFS The controller obtains the target file according to the storage address.

Optionally, when the target file is created by the processor, the target random number and the descriptor of the target file are generated. It is understandable that the file management module in the processor creates the target file, and can generate the target random number (Meta Data) and the transmission request descriptor UTRD of the target file. Among them, the target random number can uniquely correspond to the target file, and is an identifier for the uniqueness of the file. It is understandable that the random numbers corresponding to the files are different between different files. Therefore, use and When the target file is encrypted with the unique random number corresponding to the target file, the encryption level of the target file can be better improved to ensure the information security of the target file. Descriptors can be used to provide a data unit number (DUN) when the target file is encrypted in this embodiment of the application. It should also be noted that there are multiple descriptors corresponding to the file (for example, description for reading). Symbol), different commands or requests correspond to different descriptors, that is, different types of descriptors correspond to different functions. The descriptor mentioned in this application can be understood as the UFS Transfer Request Descriptor (UTRD). When the UFS controller obtains the transmission request sent by the processor, the UFS controller will go to Obtain the UTRD to implement the command and/or function corresponding to the UTRD through the UFS controller. At the same time, when the target file is created, the target random number and the descriptor of the target file are generated, which can ensure that the corresponding random numbers and descriptors of different files are different, which ensures that the file is encrypted. The encryption level increases the difficulty of cracking the encrypted target file by criminals.

Optionally, the target random number is a random number of a file attribute, and the bit width of the target random number includes one of the following bit widths: 128 bits, 192 bits, 256 bits, and 512 bits. It should be noted that this application does not specifically limit the specific bit width of the target random number. For example, the bit width of the target random number can be 128bit, 192bit, 256bit, or 512bit. In addition to the above four bit widths, it is not excluded that bit widths of other values are also applicable to file encryption in this embodiment of the application. It can be understood that the target random number is to encrypt the target file. The encryption algorithm used in the encryption process for different digits of random numbers may be the same or different. When the digits of the random number are higher, the corresponding encryption The algorithm may be more complicated, that is, the calculation process is more cumbersome, the higher the security performance, and the more conducive to file protection.

Step S302: Obtain the target random number corresponding to the target file through the UFS controller.

Specifically, the target random number (Meta Data) corresponding to the target file is obtained through the UFS controller. In the embodiment of this application, the target random number can be used in the encryption process together with the initial key to generate the file key used to encrypt the target file (that is, the second key in this application), because the target file only Uniquely corresponds to a target random number, so the file key determined according to the target random number can ensure the uniqueness of the file key. Therefore, the UFS controller needs to obtain the target random number first before encrypting the file.

Step S303: Obtain the first request descriptor corresponding to the target file through the UFS controller.

Specifically, the descriptor of the first request corresponding to the target file is obtained through the UFS controller, and the descriptor includes a data unit number DUN. Please refer to FIG. 4, which is a schematic structural diagram of a transmission request descriptor UTRD provided by an embodiment of the present application. In the process of encrypting the target file, the UFS controller needs to determine the initial encryption object of the target file according to the DUN value in the transmission request descriptor UTRD (for example: lines DW1 and DW3 shown in Figure 4), and The target descriptor also includes the storage address of the storage command, etc. (as shown in rows DW4 and DW5 in FIG. 4). The storage command can be used by the UFS controller to control the target file to perform an encrypted storage operation according to the storage command.

It can be understood that the embodiment of the present application does not specifically limit the sequence of performing step S302 and step S303. For example, the embodiment of the application may first obtain the target random number corresponding to the target file and then obtain the descriptor, or first obtain the descriptor and then obtain the target random number corresponding to the target file, or the target random number corresponding to the target file and the descriptor simultaneously Obtain.

Optionally, extend the descriptor according to the target random number by the processor to obtain an extended descriptor, where the extended descriptor includes the target random number and the DUN; The processor sends the extended descriptor to the dynamic random access memory. The obtaining the target random number corresponding to the target file by the UFS controller includes: obtaining the extended descriptor from the dynamic random access memory by the UFS controller according to the first request; The UFS controller obtains the target random number and the DUN according to the expanded descriptor. It is understandable that if the UFS controller wants to encrypt the target file with the target random number, it must first obtain the target random number, and the target random number is generated by the file management module in the processor and the descriptor together. Therefore, the UFS controller can obtain the target random number by obtaining the extended descriptor, that is, one of the ways that the UFS controller obtains the target random number based on the JESD223D protocol. Please refer to FIG. 5, which is a schematic structural diagram of an extended descriptor UTRD provided by an embodiment of the present application. For example, as shown in Figure 5, the 128-bit target random number is in the DW8-DW11 row area of the extended descriptor UTRD. It should be noted that when the number of bits of the target random number increases, the extended descriptor UTRD The number of rows also increases. It is understandable that when the file management module in the processor generates the target random number and the descriptor, it adds the target random number to the descriptor UTRD, that is, the extended descriptor can be made The UTRD can carry the target random number and be stored in the dynamic random access memory, and then the UFS controller can obtain the target random number by obtaining the extended descriptor, and then generate the key according to the target random number after obtaining the target random number. The method of obtaining the key ensures that only the target random number will appear in the file management module (ie, the software level) of the processor, and the root key (ie, the second key) is derived from the hardware logic, not It will be perceived and/or acquired by the software, so the security factor of the key will be improved.

Optionally, send the target random number to a dynamic random access memory through the processor; extend the descriptor according to the storage address of the target random number and the data length of the target random number through the processor, Obtain an extended descriptor, the extended descriptor includes the storage address of the target random number, the data length of the target random number, and the DUN; The expanded descriptor; the obtaining the target random number corresponding to the target file by the UFS controller includes: obtaining, by the UFS controller, from the dynamic random access memory according to the first request The expanded descriptor; the storage address of the target random number in the expanded descriptor is determined by the UFS controller, and the storage address of the target random number in the expanded descriptor is determined according to Obtaining the target random number by an address; obtaining, by the UFS controller, the descriptor of the first request corresponding to the target file includes: obtaining, by the UFS controller, according to the extended descriptor Said DUN.

It is understandable that after the file management module in the processor generates the target random number and stores the target random number in the dynamic random access memory, it can add the storage address of the target random number and the data length of the target random number to the descriptor UTRD That is, the extended descriptor UTRD can carry the storage address and data length of the target random number by extending the descriptor, and the UFS controller can obtain the target random number through the storage address and data length. , And the extended descriptor can also get the DUN value. For example, the extension method can be to add two lines DW8 and DW9 to the descriptor shown in Figure 4, where line DW8 can be added in the form of line DW4, line DW8 includes the storage address of the target random number, line DW9 can be The DW5 line is added, and the DW9 line includes the data length of the target random number. Therefore, based on the JESD223D protocol, the UFS controller can obtain the target random number by obtaining the storage address in the extended descriptor. After obtaining the target random number, the key is generated according to the target random number. The method of obtaining the key also ensures that only the target random number will appear in the file management module (ie, software level) of the processor, and the root secret The key (ie, the second key) The second key is derived from the hardware logic according to the first key, and will not be perceived and obtained by the software. Therefore, the security factor of the key will be improved and the criminals will be greatly reduced. The risk of cracking the file after stealing the key.

Optionally, the descriptor is sent to a dynamic random access memory through the processor; the storage address of the target random number is sent to the address register in the UFS controller through the processor; and the UFS is sent through the UFS The controller acquiring the target random number corresponding to the target file includes: acquiring the descriptor from the dynamic random access memory through the UFS controller according to the first request; and acquiring the descriptor through the UFS controller according to the The storage address of the target random number stored in the address register in the UFS controller is used to obtain the target random number. It is understandable that if the UFS controller wants to encrypt the target file with the target random number, it must first obtain the target random number, and the target random number is generated by the file management module in the processor and the descriptor together. Therefore, in addition to obtaining the target random number by obtaining the extended descriptor, the UFS controller can also receive the storage address of the target random number directly sent by the file management module to the address register of the key bank, according to the storage address Get the target random number. That is, you can control the UFS controller to add the address register of Meta Data (target random number) to the Register Space (key library) in the case of IO Memory/Register Space based on the extended protocol. The implementation method can refer to this protocol. The UTRLBA/UTRLBAU registers part in. It is also understandable that the target random number is sent to a dynamic random access memory for storage through the processor.

For example, when the UFS controller receives a UTP Transfer Request (first request), it reads the storage address of Meta Data through the Address register, and then obtains Meta Data according to the storage address. At the same time, the UFS controller can also read the descriptor UTRD from the Memory Space through the UTRLBA/UTRLBAU registers when receiving a UTP Transfer Request (first request). This file management module directly sends the target random number to the UFS controller, and the UFS controller generates an encrypted key according to the target random number. This method also ensures that only the target random number will appear in the file management module of the processor ( That is, in the software level), the first key only exists in the trusted execution environment TEE and UFS controller, so that the security factor of the key is improved. In summary, the embodiment of this application can obtain the target random number through at least three acquisition methods, and then generate the key according to the acquired target random number, which ensures that the key only exists in the hardware and does not appear in the software. At the software level, only the target random number is stored, which greatly reduces the risk of key leakage and improves the encryption level of the target file. Moreover, this method of obtaining the target random number will not affect the storage efficiency of the target file, saving Resources.

Step S304: The UFS controller generates a second key corresponding to the target file according to the target random number and the pre-stored first key.

Specifically, the UFS controller generates a second key corresponding to the target file according to the target random number and a pre-stored first key, where the first key is the initial key of the hardware configuration, and the first key is the initial key of the hardware configuration. The second key is the key used to encrypt the target file. The file key used to encrypt the target file is generated through the combination of the random number and the initial key, which can guarantee one file and one key, which improves the security of the encrypted target file coefficient. It should be noted that the pre-stored first key Class Key (ie, the initial key) is configured to UFS once by the trusted execution environment TEE in the processor after the system is powered on or when the UFS controller is initialized. In the KeyStore of the controller, the embodiment of this application avoids the frequent interaction between the trusted execution environment TEE and the UFS controller, and generates the first key for file encryption through the target random number and the first key. Two keys, one document and one secret, the possibility of being compromised is almost zero, which improves the security factor of the file key, greatly reduces the possibility of being compromised, and also improves the efficiency of use.

It is understandable that because the first key is sent by the TEE to the UFS controller, but the first key is stored in the UFS controller and cannot be read by the software, and because the second key is derived from the first key Therefore, for file encryption, only the target random number will appear in the file management module (software level), and the first key only exists in TEE and UFSHC, and the security factor is improved. Therefore, the hardware in the embodiment of this application can achieve security authentication (Protection Profile for Mobile Device, MDPP) 3.0 key system.

Optionally, before generating the second key, a random number generator may be used to generate variable parameters, and the variable parameters are used to generate the second key; the UFS controller randomly generates the second key according to the target. Generating a second key corresponding to the target file by using the UFS controller according to the target random number and the variable parameter, wherein the UFS controller generates a third key according to the target random number and the variable parameter. Variable parameters include a first variable and a second variable. The first variable is used to identify the bit width of the second key, and the second variable is a random number with a preset fixed bit width or identifies the target file. The number of the preset fixed bit width of the attribute, wherein the preset fixed bit width of the second variable is determined by the bit width of the third key; the UFS controller according to the third key And the pre-stored first key to generate the second key through a derived algorithm.

It is understandable that the third key is generated according to the target random number, the first variable parameter, and the second variable parameter, and the third key uniquely corresponds to the target file. Furthermore, it is based on the third key and the pre-stored first secret. The second key generated by the key is also unique. Therefore, the one-file-one-key encryption method greatly improves the encryption level of the file and reduces the risk of the file being stolen. Among them, for example: please refer to FIG. 6, which is a schematic diagram of a file encryption algorithm framework applied in a UFS controller provided by an embodiment of the present application. As shown in Figure 6, the third key FixData can be generated according to the target random number, the first variable L, and the second variable label through the root key module fixdataGEN. That is, Fix data Gen has three input variables, Mata Data, label, and L, and outputs a third key Fix Data with a fixed bit width. Among them, the L variable is a value representing the fixed bit width of the third key, and the Label variable can be randomly generated by the hardware random number generator trng to represent the attributes of the target file, or it can be a fixed bit width value. For example, the third key can be obtained by directly concatenating the three variables of Mata Data, label, and L. In a possible implementation manner, the specific algorithm for generating the third key Fix Data can also be found in the NIST Special Publication 800-108 protocol, which will not be repeated here in this application.

It is also understandable that after the third key is generated, the UFS controller also needs to generate a second key for file encryption through a derivative algorithm based on the third key and the pre-stored first key. key. It is also understandable that the second key is derived from hardware logic and cannot be sensed and obtained by software, which reduces the risk of being stolen by criminals. Among them, the derived algorithm (Key Derivation Functions, KDF) may also be referred to as a key acquisition function, and the KDF may include one of the following algorithms: CMAC algorithm, HMAC algorithm, and so on. For example, as shown in Figure 6, the second key FEK can be generated by the key derivation module NIST-KDF according to the third key FixData and the first key ClassKey, and the derivation algorithm used is a 256-bit CMAC algorithm. Among them, the bit width of the second key FEK is determined by the third key Fix Data and the first key Class Key. In a possible implementation manner, the specific algorithm for generating the second key FEK can also be found in the NIST Special Publication 800-108 protocol, which will not be repeated here in this application.

Step S305: The UFS controller encrypts the target file according to the second key to obtain the encrypted target file.

Specifically, the UFS controller encrypts the target file according to the second key to obtain the encrypted target file. After implementing the embodiment of the present application, after obtaining the second key uniquely corresponding to the target file, the target file can be encrypted by an encryption algorithm according to the second key and then saved, where the encryption algorithm can be a symmetric encryption algorithm, for example: The encryption algorithm may include at least one of the following methods: Advanced Encryption Standard (AES), Data Encryption Standard Lightweight Extension (DESL), International Data Encryption Algorithm (IDEA), and so on.

Optionally, the encrypting the target file by the UFS controller according to the second key to obtain the encrypted target file includes: dividing the target file into multiple files by the UFS controller File data blocks; the UFS controller starts from a file data block corresponding to the DUN in the plurality of file data blocks, and sequentially encrypts the plurality of file data blocks according to the second key to Obtain the encrypted target file. It is understandable that the embodiment of the present application can divide the target file into multiple sets of file data blocks, and then use the block encryption algorithm in the advanced encryption standard to encrypt the target file. The block encryption algorithm block length can be 128 bits, and the block encryption algorithm can be 128 bits long. The key length can be 128-bit, 192-bit or 256-bit encryption algorithm, which can greatly improve the efficiency of file encryption and storage, and also improve the encryption level of file encryption. The size of the packet file block may be 128 bits, 256 bits, etc., which is not limited in the embodiment of the present application. For example, as shown in Figure 6, plaintext[j] in Figure 6 is the data plaintext of the j-th block, with a size of 128bit; i in Figure 6 is an adjustment parameter. In the encryption engine of the UFS controller, the first The adjustment parameters of the block are initialized with the DUN value in the UTRD, and the adjustment parameters of the subsequent block will be compensated and adjusted according to the DUN value in the first UTRD; a[j] is the calculation component related to the block[j]; Cipher Text[j ] Is the ciphertext obtained after plaintext encryption of the j-th block data; AES-ENC (AES128 block encryption algorithm)/AES-DEC (AES128 block decryption algorithm) in Figure 6 is used as the basic encryption unit/basic decryption unit to perform the target file encrypt and decode. After the UFS controller obtains the file data of a predetermined length (such as 128bit) from the DRAM (that is, plaintext[j] in Figure 6), it uses FEK as the file key and the input parameters such as i, which are encrypted and stored in the memory. , And finally notify the file management module in the processor that the storage is complete.

Step S306: Store the encrypted target file in the memory.

Specifically, the encrypted target file is stored in a memory, and the encrypted target file is stored in the memory, and finally the file management module in the processor is notified that the storage is completed. It is understandable that the memory may be a solid-state hard drive of the smart terminal, UFS Flash (UFS Flash), solid-state memory, etc., which can effectively save the target file after the smart terminal encrypts the file.

Optionally, a second request is sent to the UFS controller through the processor, and the second request is used to request to read the encrypted target file; The second request is to obtain the second key corresponding to the target file, decrypt the encrypted target file according to the second key, and read it. It can be understood that when the UFS controller receives a request to read the encrypted file, it can read and decrypt the encrypted file according to the second secret key derived from the read request. The target file can only be read when there is a second key, which is conducive to the confidentiality of the target file. At the same time, the second key is derived from the hardware logic, and the software cannot perceive and obtain it, reducing the stolen by criminals. risk. For example: after ufshc reads data of a predetermined length from the specified address in the ufs device (consistent with the predetermined length of the file obtained during encryption), use FEK as the file key and input parameters such as i, and store it to the specified address of DRAM after decryption Finally, the file management module in the processor is notified that the reading is complete.

To implement the embodiments of this application, the UFS controller can obtain the random number corresponding to the target file through the first request sent by the processor; then generate the second key after encrypting it according to the random number and the pre-stored first key, and finally according to The second key encrypts the target file. First, when encrypting different files, on the basis of the same initial key (first key), different file keys (second key) can be generated through different random numbers corresponding to different files, and finally according to different Different file keys corresponding to the files respectively encrypt different files, and each file has a unique file key corresponding to it. It is understandable that because the keys used for file encryption are different between different files, it can be ensured that after the encrypted storage of the file, the encrypted file is not easy to be hacked, causing information leakage. This encryption method can greatly improve the file’s security. Encryption level. Secondly, in each file encryption process, different random numbers can be used to generate the file key based on the same initial key, which can avoid the TEE refreshing the initial file too frequently in order to increase the encryption level of the file. The key makes the encrypted storage of files inefficient and wastes resources. Furthermore, this UFS controller first obtains the target random number, and then generates the file encryption key according to the target random number. This key acquisition method ensures that the encryption key only exists at the hardware level. The key is derived from the hardware logic and will not be perceived and acquired by the software. Therefore, the security factor of the key will be greatly improved, and the possibility of being compromised is almost zero. It also improves the target file’s security. Encryption level. Finally, the chip implementation can ensure the functional isolation of the TEE and the file management module, the best security performance, and the file storage efficiency will not be affected.

The foregoing describes the method of the embodiment of the present application in detail, and the relevant device of the embodiment of the present application is provided below.

Please refer to FIG. 7, which is a schematic structural diagram of another file encryption device provided by an embodiment of the present application. The file encryption device 20 may include a first sending unit 701, a first obtaining unit 702, a key unit 703, and an encryption unit. 704, it may also include a second acquisition unit 705, a third acquisition unit 706, a first generation unit 707, a first extension unit 708, a second sending unit 709, a third sending unit 710, a second extension unit 711, and a third sending unit. Unit 7122, fourth sending unit 713, second generating unit 714, fifth sending unit 715, first storage unit 716, second storage unit 717, and decryption unit 718. Among them, the detailed description of each unit is as follows.

The first sending unit 701 is configured to send a first request to the universal flash memory host UFS controller through the processor, where the first request is used to request storage of a target file;

The first obtaining unit 702 is configured to obtain the target random number corresponding to the target file through the UFS controller;

A key unit 703, configured to generate a second key corresponding to the target file according to the target random number and a pre-stored first key through the UFS controller;

The encryption unit 704 is configured to encrypt the target file according to the second key through the UFS controller to obtain an encrypted target file.

In a possible implementation manner, the device further includes: a second obtaining unit 705, configured to obtain the target file through the UFS controller.

In a possible implementation manner, the device further includes: a third obtaining unit 706, configured to obtain, through the UFS controller, the descriptor of the first request corresponding to the target file, the descriptor including Data unit number DUN; the encryption unit 704 is specifically configured to: divide the target file into a plurality of file data blocks by the UFS controller; obtain data from the plurality of file data blocks by the UFS controller Starting from a file data block corresponding to the DUN, the multiple file data blocks are sequentially encrypted according to the second key to obtain the encrypted target file.

In a possible implementation manner, the device further includes: a first generating unit 707, configured to generate the target random number and the target random number of the target file and the target file when the target file is created by the processor. Descriptor.

In a possible implementation manner, the apparatus further includes: a first extension unit 708, configured to extend the descriptor according to the target random number by the processor to obtain an extended descriptor, and The extended descriptor includes the target random number and the DUN; the second sending unit 709 is configured to send the extended descriptor to the dynamic random access memory through the processor; the first acquiring unit 702, Specifically, the UFS controller is used to obtain the extended descriptor from the dynamic random access memory according to the first request; and the UFS controller obtains the extended descriptor according to the extended descriptor. The target random number and the DUN.

In a possible implementation manner, the apparatus further includes: a third sending unit 710, configured to send the target random number to a dynamic random access memory through the processor; and a second extension unit 711, configured to communicate through the The processor expands the descriptor according to the storage address of the target random number and the data length of the target random number to obtain an expanded descriptor, where the expanded descriptor includes the storage address of the target random number , The data length of the target random number and the DUN; a third sending unit 712, configured to send the extended descriptor to the dynamic random access memory through the processor; the first acquiring unit 702, It is specifically used to: obtain the extended descriptor from the dynamic random access memory by the UFS controller according to the first request; and determine all of the extended descriptors by the UFS controller. The storage address of the target random number, and obtain the target random number according to the storage address of the target random number; the third obtaining unit 706 is specifically configured to: use the UFS controller according to the extended description The character gets the DUN.

In a possible implementation manner, the device further includes: a fourth sending unit 713, configured to send the descriptor to the dynamic random access memory through the processor; and send the descriptor to the UFS controller through the processor The address register of the UFS sends the storage address of the target random number; the first obtaining unit 702 is specifically configured to: obtain the descriptor from the dynamic random access memory according to the first request through the UFS controller ; Obtain the target random number by the UFS controller according to the storage address of the target random number stored in the address register in the UFS controller.

In a possible implementation manner, the device further includes: a second generating unit 714, configured to generate a variable parameter through a random number generator, the variable parameter being used to generate the second key; the key The unit 703 is specifically configured to generate a third key according to the target random number and the variable parameter through the UFS controller, where the variable parameter includes a first variable and a second variable, and the first variable is used for To identify the bit width of the second key, the second variable is a random number with a preset fixed bit width or a number with a preset fixed bit width that identifies the file attribute of the target file, wherein the second variable The preset fixed bit width is determined by the bit width of the third key; the UFS controller generates the first key through a derived algorithm according to the third key and the pre-stored first key Two keys.

In a possible implementation manner, the target random number is a random number of a file attribute, and the bit width of the target random number includes one of the following bit widths: 128 bits, 192 bits, 256 bits, and 512 bits.

In a possible implementation manner, the device further includes: a first storage unit 715, configured to store the encrypted target file in a memory through the UFS controller; and a second storage unit 716, configured to access The memory stores the encrypted target file.

In a possible implementation manner, the device further includes: a fifth sending unit 717, configured to send a second request to the UFS controller through the processor, and the second request is used to request a request to the UFS controller. The encrypted target file is read; the decryption unit 718 is configured to obtain the second key corresponding to the target file according to the second request through the UFS controller, and convert the second key corresponding to the target file according to the second key. The encrypted target file is read after decryption.

It should be noted that the functions of each functional unit in the file encryption device 20 described in the embodiment of the present application can be referred to the related description of step S301 to step S306 in the method embodiment described in FIG. 3, which will not be repeated here. .

As shown in FIG. 8, FIG. 8 is a schematic structural diagram of another file encryption apparatus provided by an embodiment of the present application. The apparatus 30 includes at least one processor 801, at least one memory 802, and at least one UFS controller 803. In addition, the device may also include general components such as antennas, which will not be described in detail here.

The processor 801 may be a general-purpose central processing unit (CPU), a microprocessor, an application-specific integrated circuit (ASIC), or one or more integrated circuits for controlling the execution of the programs of the above solutions.

The UFS controller 803, which may be a solid state hard disk, is composed of a control unit and a storage unit.

The memory 802 may be a read-only memory (ROM) or other types of static storage devices that can store static information and instructions, random access memory (RAM), or other types that can store information and instructions The dynamic storage device can also be electrically erasable programmable read-only memory (Electrically Erasable Programmable Read-Only Memory, EEPROM), CD-ROM (Compact Disc Read-Only Memory, CD-ROM) or other optical disc storage, optical disc storage (Including compact discs, laser discs, optical discs, digital versatile discs, Blu-ray discs, etc.), magnetic disk storage media or other magnetic storage devices, or can be used to carry or store desired program codes in the form of instructions or data structures and can be used by a computer Any other media accessed, but not limited to this. The memory can exist independently and is connected to the processor through a bus. The memory can also be integrated with the processor.

Wherein, the memory 802 is used to store application program codes for executing the above solutions, and is controlled and executed by the processor 801 and the UFS controller 803. The processor 801 and the UFS controller 803 are configured to execute application program codes stored in the memory 802.

The code stored in the memory 802 can execute the file encryption method provided in FIG. 3 above. For example, the processor sends a first request to the universal flash memory host UFS controller, and the first request is used to request storage of the target file; The controller obtains the target random number corresponding to the target file; the UFS controller generates the second key corresponding to the target file according to the target random number and the pre-stored first key; and the UFS controls The device encrypts the target file according to the second key to obtain an encrypted target file.

It should be noted that the functions of each functional unit in the file encryption device 30 described in the embodiment of the present application can refer to the related descriptions of step S301 to step S306 in the method embodiment described in FIG. 3, which will not be repeated here. .

In the above-mentioned embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in an embodiment, reference may be made to related descriptions of other embodiments.

It should be noted that for the foregoing method embodiments, for the sake of simple description, they are all expressed as a series of action combinations, but those skilled in the art should know that this application is not limited by the described sequence of actions. Because according to this application, some steps may be performed in other order or at the same time. Secondly, those skilled in the art should also know that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by this application.

In the several embodiments provided in this application, it should be understood that the disclosed device may be implemented in other ways. For example, the device embodiments described above are only illustrative, for example, the division of the above-mentioned units is only a logical function division, and there may be other divisions in actual implementation, for example, multiple units or components can be combined or integrated. To another system, or some features can be ignored, or not implemented. In addition, the displayed or discussed mutual coupling or direct coupling or communication connection may be indirect coupling or communication connection through some interfaces, devices or units, and may be in electrical or other forms.

The units described above as separate components may or may not be physically separate, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the objectives of the solutions of the embodiments.

In addition, the functional units in the embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units may be integrated into one unit. The above-mentioned integrated unit can be implemented in the form of hardware or software functional unit.

If the above integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer readable storage medium. Based on this understanding, the technical solution of the present application essentially or the part that contributes to the existing technology or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium , Including several instructions to enable a computer device (which may be a personal computer, a server or a network device, etc., specifically a processor in a computer device) to execute all or part of the steps of the above methods of the various embodiments of the present application. Among them, the aforementioned storage media may include: U disk, mobile hard disk, magnetic disk, optical disk, read-only memory (Read-Only Memory, abbreviation: ROM) or Random Access Memory (Random Access Memory, abbreviation: RAM), etc. A medium that can store program codes.

As mentioned above, the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: The technical solutions recorded in the embodiments are modified, or some of the technical features are equivalently replaced; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

A file encryption device, characterized by comprising: a processor and a universal flash memory host UFS controller coupled with the processor;

The processor is configured to send a first request to the UFS controller, where the first request is used to request storage of a target file;

The UFS controller is used for:

Acquiring a target random number corresponding to the target file;

Generating a second key corresponding to the target file according to the target random number and the pre-stored first key;

The target file is encrypted by the second key to obtain an encrypted target file.
The device according to claim 1, wherein the UFS controller is further configured to: obtain the target file.
The device according to claim 1 or 2, wherein the UFS controller is further used for:

Acquiring a descriptor of the first request corresponding to the target file, where the descriptor includes a data unit number DUN;

The UFS controller is specifically configured to: divide the target file into multiple file data blocks;

Starting from a file data block corresponding to the DUN in the plurality of file data blocks, the plurality of file data blocks are sequentially encrypted according to the second key to obtain the encrypted target file.
The device according to claim 3, wherein the processor is further configured to:

When the target file is created, the target random number and the descriptor of the target file are generated.
The device according to claim 4, wherein the device further comprises a dynamic random access memory coupled with the processor and the UFS controller respectively;

The processor is further configured to: expand the descriptor according to the target random number to obtain an expanded descriptor, where the expanded descriptor includes the target random number and the DUN;

Sending the extended descriptor to the dynamic random access memory;

The UFS controller is specifically used for:

Obtaining the extended descriptor from the dynamic random access memory according to the first request;

According to the expanded descriptor, the target random number and the DUN are acquired.
The device according to claim 4, wherein the device further comprises a dynamic random access memory coupled with the processor and the UFS controller respectively;

The processor is further configured to: send the target random number to the dynamic random access memory;

The descriptor is expanded according to the storage address of the target random number and the data length of the target random number to obtain an expanded descriptor. The expanded descriptor includes the storage address of the target random number and the data length of the target random number. The data length of the target random number and the DUN;

Sending the extended descriptor to the dynamic random access memory;

The UFS controller is specifically used for:

Obtaining the extended descriptor from the dynamic random access memory according to the first request;

Determine the storage address of the target random number in the extended descriptor, and obtain the target random number according to the storage address of the target random number;

Obtain the DUN according to the expanded descriptor.
The device according to claim 4, wherein the device further comprises a dynamic random access memory coupled with the processor and the UFS controller respectively;

The processor is further configured to: send the descriptor to the dynamic random access memory;

Sending the storage address of the target random number to the address register in the UFS controller;

The UFS controller is specifically used for:

Obtaining the descriptor from the dynamic random access memory according to the first request;

Obtain the target random number according to the storage address of the target random number stored in the address register in the UFS controller.
The device according to any one of claims 1-7, wherein the device further comprises: a random number generator coupled with the UFS controller, the random number generator is used to generate variable parameters, the The variable parameter is used to generate the second key;

The UFS controller is specifically used for:

Generating a third key according to the target random number and the variable parameter, wherein the variable parameter includes a first variable and a second variable, and the first variable is used to identify the bit width of the second key; The second variable is a random number with a preset fixed bit width or a number with a preset fixed bit width identifying the file attribute of the target file, wherein the preset fixed bit width of the second variable is determined by the first The bit width of the three keys is determined;

The second key is generated through a derived algorithm according to the third key and the pre-stored first key.
The device according to any one of claims 1-8, wherein the target random number is a random number of a file attribute, and the bit width of the target random number includes one of the following bit widths: 128 bits, 192 Bit, 256 bit, 512 bit.
9. The device according to any one of claims 1-9, wherein the processor is further configured to:

Sending a second request to the UFS controller, where the second request is used to request to read the encrypted target file;

The UFS controller is also used for:

According to the second request, the second key corresponding to the target file is obtained, and the encrypted target file is decrypted and read according to the second key.
A file encryption method, characterized in that it comprises:

Sending a first request to the universal flash memory host UFS controller through the processor, where the first request is used to request storage of the target file;

Obtaining the target random number corresponding to the target file through the UFS controller;

Generating the second key corresponding to the target file by the UFS controller according to the target random number and the pre-stored first key;

The UFS controller encrypts the target file according to the second key to obtain an encrypted target file.
The method of claim 11, wherein the method further comprises:

Obtain the target file through the UFS controller.
The method according to claim 11 or 12, wherein the method further comprises:

Acquiring, by the UFS controller, the descriptor of the first request corresponding to the target file, where the descriptor includes a data unit number DUN;

The encrypting the target file by the UFS controller according to the second key to obtain the encrypted target file includes: dividing the target file into a plurality of file data blocks by the UFS controller ；

The UFS controller starts from a file data block corresponding to the DUN among the plurality of file data blocks, and sequentially encrypts the plurality of file data blocks according to the second key to obtain the encrypted The target file.
The method of claim 13, wherein the method further comprises:

When the target file is created by the processor, the target random number and the descriptor of the target file are generated.
The method of claim 14, wherein the method further comprises:

Expanding the descriptor according to the target random number by the processor to obtain an expanded descriptor, where the expanded descriptor includes the target random number and the DUN;

Sending the extended descriptor to a dynamic random access memory through the processor;

The obtaining the target random number corresponding to the target file by the UFS controller includes:

Obtaining, by the UFS controller, the extended descriptor from the dynamic random access memory according to the first request;

The UFS controller obtains the target random number and the DUN according to the expanded descriptor.
The method of claim 14, wherein the method further comprises:

Sending the target random number to a dynamic random access memory through the processor;

The processor expands the descriptor according to the storage address of the target random number and the data length of the target random number to obtain an expanded descriptor, where the expanded descriptor includes the target random number The storage address of, the data length of the target random number, and the DUN;

Sending the extended descriptor to the dynamic random access memory through the processor;

The obtaining the target random number corresponding to the target file by the UFS controller includes:

Obtaining, by the UFS controller, the extended descriptor from the dynamic random access memory according to the first request;

Determine the storage address of the target random number in the extended descriptor by the UFS controller, and obtain the target random number according to the storage address of the target random number;

The obtaining, by the UFS controller, the descriptor of the first request corresponding to the target file includes:

Obtain the DUN according to the extended descriptor through the UFS controller.
The method according to claim 14, wherein the processor is further configured to:

Sending the descriptor to a dynamic random access memory through the processor;

Sending the storage address of the target random number to the address register in the UFS controller through the processor;

The obtaining the target random number corresponding to the target file by the UFS controller includes:

Acquiring, by the UFS controller, the descriptor from the dynamic random access memory according to the first request;

The UFS controller obtains the target random number according to the storage address of the target random number stored in the address register in the UFS controller.
The method according to any one of claims 11-17, wherein the method further comprises: generating a variable parameter through a random number generator, and the variable parameter is used to generate the second key;

The generating, by the UFS controller, the second key corresponding to the target file according to the target random number and the pre-stored first key includes:

The UFS controller generates a third key according to the target random number and the variable parameter, where the variable parameter includes a first variable and a second variable, and the first variable is used to identify the second variable. The bit width of the key, the second variable is a random number with a preset fixed bit width or a number with a preset fixed bit width identifying the file attribute of the target file, wherein the preset fixed bit width of the second variable The bit width is determined by the bit width of the third key;

The UFS controller generates the second key through a derived algorithm according to the third key and the pre-stored first key.
The method according to any one of claims 11-18, wherein the target random number is a random number of a file attribute, and the bit width of the target random number includes one of the following bit widths: 128 bits, 192 Bit, 256 bit, 512 bit.
The method according to any one of claims 11-19, wherein the method further comprises:

Sending a second request to the UFS controller through the processor, where the second request is used to request to read the encrypted target file;

The UFS controller obtains the second key corresponding to the target file according to the second request, and decrypts the encrypted target file according to the second key and reads it.
A computer storage medium, characterized in that the computer storage medium stores a computer program, and when the computer program is executed by a processor, the method according to any one of claims 11-20 is realized.
A computer program, characterized in that the computer program includes instructions, which when the computer program is executed by a computer, cause the computer to execute the method according to any one of claims 11-20.