CN117453258A - Embedded equipment and upgrading method thereof - Google Patents

Abstract

The invention discloses an embedded device and an upgrading method thereof, wherein the method comprises the following steps: creating a backup partition and a backup system, and storing the backup system in the backup partition; storing work flows through the environment variable partition, and identifying the work flow of the current equipment, wherein the work flows comprise an upgrading flow and a normal flow; the upgrade process is executed, and the backup system is loaded into the memory of the embedded equipment from the backup partition through a quick starting mechanism, so that when the embedded equipment encounters unexpected hardware problems to cause upgrade suspension, the upgrade process can be continuously executed after the embedded equipment is powered on again; after the upgrading is successful, modifying the current working flow into a normal flow, and restarting; the backup system can be written into the partition once, the device can read the partition when running, the requirement of the embedded device on the storage space is obviously reduced, the probability of the embedded device upgrading damage is reduced, and the reliability and the safety of the embedded device upgrading process are improved.

Description

Embedded equipment and upgrading method thereof

Technical Field

The invention relates to the technical field of computer embedded software, in particular to embedded equipment and an upgrading method thereof.

Background

OpenWrt is an embedded operating system based on Linux (an operating system), specifically designed for embedded devices such as routers, wireless devices, etc. Flash Memory (Flash Memory), a form of electronically erasable programmable read-only Memory, allows Memory to be erased or written multiple times during operation. OpenWrt mainly operates on embedded devices based on Flash (a storage device for short) storage, such as NAND Flash and NOR Flash. In Flash storage devices, there are typically several partitions: boot (BootLoader) partition, environment variable (bootv) partition, firmware (Firmware) partition, and file system data (rootfs_data) partition. The several partitions are specifically described as follows:

BootLoader partition: this is the first program that the device starts, and it is the responsibility of the device to initialize hardware and load a kernel to start the operating system. Its main task is to load and execute Kernel, while also providing some important functions for system recovery.

Bootenv partitioning: this partition stores the environment variables required during the boot process, such as device model, MAC (MediaAccess Control ) address, etc.

Firmware partition: the kernel and file system of this partitioned storage device includes the OpenWrt system itself. At system upgrade, new firmware is written to this partition.

Rootfs_data partition: this part is the file system of the embedded device for storing data of device configuration, application programs, etc.

When the OpenWrt system is upgraded, a Ramfs file system (memory file system) is read from Flash and is switched into memory from a normal Rootfs (root file system), and then the original Firmware partition in Flash is erased to realize the upgrading of Firmware.

Flash is a short term for memory devices, flash memory (Flash memory), a form of electronically erasable programmable read-only memory, which allows memory to be erased or written to multiple times during operation. Flash memory is a non-volatile memory, has the characteristics of low power consumption, small size, random access support and the like, and is widely applied to embedded equipment. Flash storage realizes data writing by erasing and writing in units of blocks, and therefore, writing errors of the data, such as unstable power supply, incorrect writing flow and the like, are easily caused by the influence of various factors in the data writing process. The read operation is generally less error-prone because it does not require erasing of Flash.

At present, the upgrading of routers and wireless devices is generally realized by erasing and writing data to Firmware partitions. This means that if an unexpected hardware failure or data writing error is encountered during the device upgrade, the device upgrade may fail, and even the device may not recover.

In summary, the existing embedded equipment upgrading method still has the problems of more occupied storage space and higher upgrading failure rate.

Disclosure of Invention

The invention aims to solve the technical problems that the existing embedded equipment upgrading method occupies more storage space and has higher upgrading failure rate, and provides an embedded equipment and an upgrading method thereof.

The technical problems of the invention are solved by the following technical scheme:

an embedded device upgrading method comprises the following steps:

s1, creating a backup partition and a backup system, and storing the backup system in the backup partition;

s2, storing work flows through environment variable partition, and identifying the work flow of the current equipment, wherein the work flows comprise an upgrading flow and a normal flow;

s3, executing an upgrading process, and loading the backup system into the memory of the embedded equipment from the backup partition through a quick starting mechanism, so that when the embedded equipment encounters an unexpected hardware problem to cause upgrading suspension, the upgrading process can be continuously executed after the embedded equipment is powered on again;

s4, after the upgrading is successful, the current working flow is modified into a normal flow, and restarting is carried out.

In some embodiments, the method further comprises the following technical characteristics:

step S3 further comprises the steps of: and verifying the upgrading flow based on a verification algorithm, identifying abnormal firmware when the firmware data writing errors are encountered, and repairing the firmware.

In some embodiments, the method further comprises the steps of:

s5, executing a normal flow, checking the normal flow based on a checking algorithm, and when the firmware data reading error is encountered, changing the working flow and executing an upgrading flow.

In some embodiments, the verification algorithm is a non-cryptographic hash algorithm.

In some embodiments, verifying the upgrade procedure includes the steps of:

e1, after uploading the firmware, calculating a 32-bit hash value of the firmware to obtain a first hash value, and writing the firmware into a firmware partition through a storage technology device read-write tool;

e2, after the firmware is written in, reading the firmware from the storage device and recalculating the hash value to obtain a second hash value;

e3, comparing the first hash value with the second hash value, if the first hash value and the second hash value are consistent, writing the second hash value into the tail of the firmware partition after alignment, modifying the workflow into a normal flow, and restarting;

and E4, if the two are inconsistent, inquiring whether the user tries to rewrite the firmware, and circularly executing the steps E1 to E3.

In some embodiments, checking the normal flow includes the steps of:

f1, reading firmware of the firmware partition into a memory, and performing hash value calculation to obtain a third hash value;

f2, comparing the third hash value with a second hash value at the end of the firmware partition, and if the third hash value is consistent with the second hash value, normally loading the firmware of the firmware partition; if the two are inconsistent, the current workflow is modified into an upgrade workflow, and steps E1 to E3 are executed.

In some embodiments, the backup system in step S1 includes a kernel and a file system, and the backup system is 1.5M to 2M in size.

In some embodiments, the backup system further includes a Flash driver and a network driver, the kernel is a Linux kernel, and the file system is built through a busy box; the file system provides a Web upgrade page for a user by providing Unix tools and commands and integrating an Http server.

In some embodiments, the fast start mechanism in step S3 is a Kexec mechanism.

The invention also provides the following technical scheme:

an embedded device comprising a processor and a memory, the memory having stored therein a computer program executable by the processor to perform the steps of the method as described above.

Compared with the prior art, the invention has the beneficial effects that:

according to the embedded equipment upgrading method, the backup partition and the backup system are created, the backup system is loaded from the backup partition to the internal memory of the embedded equipment through the quick starting mechanism, and the technical characteristics of the backup system can be set, so that the backup system can be written into the partition only once, and equipment can read the partition only when in operation, so that the technical problems that the existing upgrading method occupies more storage space and has higher upgrading failure rate are solved, and the effects of remarkably reducing the requirement of the embedded equipment upgrading on the storage space, reducing the probability of the embedded equipment upgrading damage and improving the reliability and safety of the embedded equipment upgrading process are achieved.

Furthermore, in some embodiments, the following benefits are also provided:

the embodiment of the invention adopts the non-encrypted hash algorithm as a verification method to verify the upgrade flow (data writing process) and the normal flow (equipment starting process), has the characteristics of high speed and low conflict, can obviously improve the verification speed and reliability, ensures the user experience and ensures the accuracy and reliability of data writing.

The embodiment of the invention uses Kexec mechanism to load the backup system, can obviously reduce the requirement on Flash space while rapidly starting the upgrading process, and is particularly important in devices with smaller storage space, such as routers and gateways.

Other advantages of embodiments of the present invention are further described below.

Drawings

FIG. 1 is a diagram illustrating Flash partition adjustment according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of an apparatus upgrade process according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of a device start-up procedure according to an embodiment of the present invention;

FIG. 4 is a schematic diagram of the structure and function of a fail-safe system according to an embodiment of the present invention;

fig. 5 is a flowchart of an upgrade method of an embedded device according to an embodiment of the present invention.

Detailed Description

The following describes embodiments of the present invention in detail. It should be emphasized that the following description is merely exemplary in nature and is in no way intended to limit the scope of the invention or its applications.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the embodiments of the present invention, the meaning of "plurality" is two or more, unless explicitly defined otherwise.

Before describing the embodiment of the invention, the idea of the invention is described as follows:

in the process of upgrading embedded devices, the industry currently generally adopts the following ways to fix or avoid problems: 1. the upgrade is not ensured, and only a user is required to ensure the stability of the power supply, and professional tools such as tftpd (a data transmission tool) and the like are provided for recovering the upgrade damaged equipment after the upgrade fault occurs. 2. The method of double Firmware partitions is adopted, namely two Firmware partitions with the same size are divided in Flash, alternate writing is carried out in upgrading, and the current starting Firmware is controlled through Bootloader and Bootenv, so that whether upgrading is successful or not can be ensured to have a starting Firmware. The first method has the defects that: no protective measures exist, the probability of failure is high, and the users are required to have higher professional literacy; the second approach suffers from two drawbacks: 1. the use of dual partitions occupies more Flash space, which is generally smaller for embedded devices; 2. if the write-in check and the start-up check are not performed, the equipment considers that the upgrade is successful, and the written-in data is in error, and at the moment, the restarting crash risk exists. Based on the defects of the prior method, the invention provides a new upgrading method: a safe and reliable Openwrt equipment upgrading method is used for realizing that when equipment encounters an upgrading suspension (power-off and the like) caused by an unexpected hardware problem, an upgrading repair flow can be continuously executed when the equipment is powered on again to repair damaged firmware, and when the equipment encounters a Flash self firmware data writing error during upgrading, abnormal firmware can be identified to repair the firmware. The method of the invention can ensure that the firmware is written correctly, does not occupy excessive Flash space, and does not need professional operation for recovery by a user when abnormality occurs.

Examples

The embodiment of the invention provides an embedded equipment upgrading method, as shown in fig. 5, comprising the following steps:

s1, creating a backup partition and a backup system, and storing the backup system in the backup partition;

s2, storing work flows through environment variable partition, and identifying the work flow of the current equipment, wherein the work flows comprise an upgrading flow and a normal flow;

s3, executing an upgrading process, and loading the backup system into the memory of the embedded equipment from the backup partition through a quick starting mechanism, so that when the embedded equipment encounters an unexpected hardware problem to cause upgrading suspension, the upgrading process can be continuously executed after the embedded equipment is powered on again;

s4, after the upgrading is successful, the current working flow is modified into a normal flow, and restarting is carried out.

The following is a detailed description of the method of this example:

1. preparation stage

(1) Partition adjustment:

creating a backup partition and a backup system, and storing the backup system in the backup partition.

Specifically, as shown in fig. 1, a new backup partition is created between a Bootenv partition and a Firmware partition on the basis of the original partition of Flash, and is used for storing a backup system. Specifically, the backup Partition is a Fail-Safe Partition (Fail-Safe Partition), and the backup System is a Fail-Safe System (Fail-Safe System). The failsafe partition is a storage partition in the storage medium that is used to house the failsafe system.

(2) Fail-Safe System composition:

as shown in FIG. 4, the Fail-Safe System includes the most compact Linux kernel, minimal file System and applications, and the necessary Flash drivers and network drivers. The minimum file system is built by using a Busybox (an open source project) to provide basic Unix (an operating system) tools and commands, and meanwhile, a Http (HyperTextTransferprotocol) server is integrated to provide a Web upgrade page for a user. Because of the use of the reduced kernel and file system, its size is smaller than that of a normal operating system, only 1.5M to 2M. The application comprises hash value calculation and verification; writing and reading Flash; and starting a logic control method by the Http server.

(3) Workflow classification

The Workflow (Workflow) is stored by the environment variable partition, identifying what Workflow the current device is in.

Specifically, one environment variable is stored by Bootenv partition. A Bootenv partition is a memory partition that stores some data, where state values for the workflow are stored to the partition primarily so that the operating system can learn about its own operating state. Preferably, the environment variable is Workflow, which is used to identify what Workflow the current device is in. The workflow includes the following two kinds:

normal (Normal flow), update (upgrade flow).

2. Upgrade process

1. The upgrading process comprises the following steps:

and executing an upgrading process, and loading the backup system into the memory of the embedded equipment from the backup partition through a quick starting mechanism, so that when the embedded equipment encounters unexpected hardware problems to cause upgrading suspension, the upgrading process can be continuously executed after the embedded equipment is powered on again. And verifying the upgrading flow based on a verification algorithm, identifying abnormal firmware when the firmware data writing errors are encountered, and repairing the firmware. And after the upgrading is successful, modifying the current working flow into a normal flow, and restarting. The fast boot mechanism is preferably a Kexec (a tool for replacing kernels on the fly) mechanism and the verification algorithm is preferably a non-cryptographic hash algorithm (xxHash). As shown in fig. 2, the process of upgrading the embedded device specifically includes the following steps:

a1, when a user needs to upgrade firmware, an upgrade flow is triggered through Web, and the Workflow is modified into Update. The specific mode of Web triggering is as follows: the Web page provides an upgrade page and the user may trigger an upgrade process by clicking an upgrade button on the Web page.

A2, the OpenWrt System loads the Fail-Safe System into the memory from the Fail-Safe Partition through Kexec, and executes jump. Kexec allows another kernel to be booted directly at the time of Linux kernel execution for rapid startup of the Fail-Safe System without requiring a full restart of the hardware.

A3, the Fail-Safe System reads the current Workflow, and when the current Workflow is in Update, a firmware uploading Web page is displayed, and a user is guided to upload new firmware to the file System data partition.

And A4, after the user uploads the Firmware, calculating 32-bit xxHash of the Firmware to obtain a first hash value (hashA), and writing the Firmware into a Firmware partition through a mtd (Memory Technology Device, storage technical equipment) read-write tool.

And A5, after the firmware is written, reading the firmware from the Flash, and recalculating the xxHash to obtain a second hash value (hashB).

And A6, comparing the hashA with the hashB, if the hashA and the hashB are consistent, namely, the verification is successful, writing the hash B into the end of the firmware partition after alignment, changing the Workflow, modifying the Workflow into Normal, restarting, and guiding to start a Normal operating system according to the working state of the Normal.

2. Upgrade flow exception handling mechanism:

the embedded device can change the workflow into update when upgrading, and can remain in the state when upgrading is abnormal until upgrading is successful, and the embedded device can not be switched to normal. The specific processing logic method for the embedded equipment upgrade exception processing specifically comprises the following steps:

b1, firmware is not uploaded or unexpected faults (power failure) occur in the uploading process, and the workflow state is not changed at the moment, the upgrading process is still carried out, and the original Firmware partition is not modified, so that the Firmware is electrified again at the moment and then is upgraded.

B2, unexpected faults (power failure) occur in the firmware writing process to cause writing failure, at the moment, the Workflow becomes Update, and after restarting the equipment, the upgrading process is continuously executed.

B3, as shown in FIG. 2, after the Firmware writing is completed, the recalculated hash B is inconsistent with the hash A calculated before writing, which indicates that Firmware writing has abnormality and needs to be rewritten. At this time, the user is asked whether to attempt to rewrite the firmware, and the operations of steps A4, A5, and A6 of the upgrade process are circularly performed.

3. The starting process comprises the following steps:

and executing the normal flow, checking the normal flow based on a checking algorithm, and when the firmware data reading error is encountered, performing work flow change and executing the upgrading flow. When in starting, a starting logic control method is adopted to guide the jump, check, loading and upgrade repair logic. The verification algorithm is preferably a non-cryptographic hash algorithm (xxHash). As shown in fig. 3, the method for controlling the start logic of the device start process specifically includes the following steps:

c1, when equipment is started, bootloader guides to jump to a Fail-Safe System;

c2, the Fail-Safe System determines the current flow according to the Workflow, and guides the user to upgrade when the user is in Update, and the steps 4, 5 and 6 of the upgrade flow are executed.

And C3, when the Workflow is in Normal, reading Firmware partition Firmware into the memory, and performing xxHash calculation to obtain a third hash value (hash C).

C4, comparing the hash C with the hash B at the end of the Firmware partition, and normally loading Firmware if the hash C is consistent with the hash B at the end of the Firmware partition;

and C5, if the Workflow is inconsistent, carrying out Workflow change, modifying the current Workflow into Update, and executing steps A4, A5 and A6 of the upgrading flow.

By the technical scheme, unexpected faults, writing errors and reading errors in the upgrading process can be ensured, and the upgrading recovery can be continued without complex operation. By adopting a Kexec mode, reliable upgrading can be realized without occupying too much Flash space. Meanwhile, the xxHash is adopted in the verification method, so that the verification speed can be remarkably increased, and the user experience is ensured.

The embodiment of the invention also provides an embedded device comprising a processor and a memory, the memory having stored therein a computer program executable by the processor to perform the steps of the method as described above.

The embodiment of the invention realizes the following technical effects:

1. the backup system is only written into the Flash partition once, equipment only reads the partition when running, the probability of damage is extremely low, and the reliability and the safety of the upgrading process are improved.

2. Compared with a mode of using double partition upgrade, a mode of using Kexec to load a backup system can remarkably reduce the requirement on Flash space, and is particularly important in devices with smaller storage space, such as routers and gateways.

3. Hash check algorithms are added in the data writing and system starting processes, so that the accuracy and reliability of data writing can be ensured.

4. The xxHash is adopted as a verification method, so that the method has the characteristics of high speed and low conflict, the verification speed can be remarkably improved, and the user experience is ensured.

5. The method of the embodiment of the invention can be applied to different Flash storage devices and Linux systems, and has stronger universality and compatibility.

Alternative/variations of embodiments of the invention:

1. by simply adding backup partitions but not performing xxHash checking, the speed and reliability of checking may be reduced.

2. The deformation scheme is as follows: different verification algorithms, such as SHA-256 instead of xxHash, are used, or the way and content of construction of the backup system is changed.

The innovation points of the embodiment of the invention are as follows:

1. upgrades were performed using Kexec: and a Kexec mechanism is used for loading the Fail-Safe System, so that the upgrade process is started rapidly, and the Flash storage space is saved.

2. Upgrade exception handling mechanism: specific processing logic methods are designed for various abnormal conditions such as power failure, firmware writing abnormality and the like.

3. The special design method of the starting process comprises the following steps: the design method of the boot jump, check, loading and upgrade repair logic during starting.

It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

The foregoing is a further detailed description of the invention in connection with specific/preferred embodiments, and it is not intended that the invention be limited to such description. It will be apparent to those skilled in the art that several alternatives or modifications can be made to the described embodiments without departing from the spirit of the invention, and these alternatives or modifications should be considered to be within the scope of the invention. In the description of the present specification, reference to the terms "one embodiment," "some embodiments," "preferred embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Those skilled in the art may combine and combine the features of the different embodiments or examples described in this specification and of the different embodiments or examples without contradiction. Although embodiments of the present invention and their advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the scope of the invention as defined by the appended claims.

Claims (10)

1. An embedded device upgrading method is characterized by comprising the following steps:

s1, creating a backup partition and a backup system, and storing the backup system in the backup partition;

s2, storing work flows through environment variable partition, and identifying the work flow of the current equipment, wherein the work flows comprise an upgrading flow and a normal flow;

s3, executing an upgrading process, and loading the backup system into the memory of the embedded equipment from the backup partition through a quick starting mechanism, so that when the embedded equipment encounters an unexpected hardware problem to cause upgrading suspension, the upgrading process can be continuously executed after the embedded equipment is powered on again;

s4, after the upgrading is successful, the current working flow is modified into a normal flow, and restarting is carried out.

2. The embedded device upgrade method of claim 1, wherein step S3 further comprises the steps of: and verifying the upgrading flow based on a verification algorithm, identifying abnormal firmware when the firmware data writing errors are encountered, and repairing the firmware.

3. The embedded device upgrade method of claim 2, further comprising the steps of:

s5, executing a normal flow, checking the normal flow based on a checking algorithm, and when the firmware data reading error is encountered, changing the working flow and executing an upgrading flow.

4. A method of upgrading an embedded device according to claim 2 or 3, wherein the verification algorithm is a non-cryptographic hash algorithm.

5. The method for upgrading an embedded device according to claim 4, wherein verifying the upgrading process comprises the steps of:

e1, after uploading the firmware, calculating a 32-bit hash value of the firmware to obtain a first hash value, and writing the firmware into a firmware partition through a storage technology device read-write tool;

e2, after the firmware is written in, reading the firmware from the storage device and recalculating the hash value to obtain a second hash value;

e3, comparing the first hash value with the second hash value, if the first hash value and the second hash value are consistent, writing the second hash value into the tail of the firmware partition after alignment, modifying the workflow into a normal flow, and restarting;

and E4, if the two are inconsistent, inquiring whether the user tries to rewrite the firmware, and circularly executing the steps E1 to E3.

6. The embedded device upgrade method of claim 5, wherein verifying the normal flow comprises the steps of:

f1, reading firmware of the firmware partition into a memory, and performing hash value calculation to obtain a third hash value;

f2, comparing the third hash value with a second hash value at the end of the firmware partition, and if the third hash value is consistent with the second hash value, normally loading the firmware of the firmware partition; if the two are inconsistent, the current workflow is modified into an upgrade workflow, and steps E1 to E3 are executed.

7. The embedded device upgrade method of claim 1, wherein the backup system in step S1 includes a kernel and a file system, and the backup system has a size of 1.5M to 2M.

8. The embedded device upgrading method according to claim 7, wherein the backup system further comprises a Flash driver and a network driver, the kernel is a Linux kernel, and the file system is built through a busy box; the file system provides a Web upgrade page for a user by providing Unix tools and commands and integrating an Http server.

9. The embedded device upgrade method of claim 1, wherein the fast boot mechanism in step S3 is a Kexec mechanism.

10. An embedded device comprising a processor and a memory, the memory having stored therein a computer program, characterized in that the computer program is executable by the processor to implement the steps of the method according to any of claims 1-9.