CN103034811B - A kind of method, system and device of file process - Google Patents

Abstract

The invention discloses a file processing method, system and device, which are used to improve the file processing capability of the Android operating system while ensuring the security of the Android operating system. The method includes: the kernel layer receives the message sent by the application layer, the kernel layer verifies the received message, and when the verification is passed, executes the file included in the message that the application layer does not have permission to execute Process commands.

Description

Method, system and device for file processing

technical field

The present invention relates to the technical field of operating systems, in particular to a file processing method, system and device.

Background technique

In recent years, the Android operating system has become more and more widely used due to its open source nature, and embedded devices such as smartphones and tablet computers developed using the Android system emerge in endlessly.

The Android operating system is an operating system based on the Linux2.6 kernel, which is divided into four layers: the linux kernel layer, the system runtime layer, the application framework layer and the application layer. Among them, the Linux kernel layer, that is, the kernel layer includes the core system services of Android, such as security, memory management, process management, etc.; the system runtime layer mainly includes the program library and the android runtime library, and the program library can be used by different Android systems Component usage, the Android runtime library provides most of the functions of the core library of the JAVA programming language; the application framework layer is the API framework used by the core application, and developers can also use these frameworks to develop their own applications; the application layer uses Java A program written in a language that runs on a virtual machine.

Since Android is based on the Linux kernel, the Android security system is also based on the Linux security architecture. Linux is a multi-user, multi-task operating system, and users and components play an important role. Different users and components have different access attributes to the same file, which makes the Linux system more secure. Therefore, in the Android operating system, the system creates a user and component for each application. These users and components are common users, they cannot access the data of the Linux kernel layer, they can only access the files and directories of the corresponding applications, and they cannot access the data of other applications. This protects the private data of the application program, isolates the application from the application, and the application from the system, and enhances the security and robustness of the system.

It can be seen that in the current Android operating system, each application program has only the system (system) authority, and does not have the highest authority, that is, the root (root) authority, so that only private data can be operated. In this way, although the security of the system is enhanced , but it also brings some problems. When the application layer program, that is, the application program needs to perform some operations on system files, such as copying or modifying file content and attributes to the system directory, configuring network addresses, etc., all of these require users with the highest authority (root authority) to be able to Operations, since the application only has system permissions, these operations cannot be performed.

Contents of the invention

Embodiments of the present invention provide a file processing method, system and device, which are used to improve the file processing capability of the Android operating system while ensuring the security of the Android operating system.

An embodiment of the present invention provides a method for file processing, including:

The kernel layer receives the message sent by the application layer;

The kernel layer verifies the received message, and when the verification is passed, executes the file processing command included in the message that the application layer has no authority to execute.

An embodiment of the present invention provides a file processing system, including: an application layer and a kernel layer, wherein,

The application layer is configured to send a message to the kernel layer;

The kernel layer is configured to receive the message, verify the received message, and execute a file processing command included in the message that the application layer has no authority to execute when the verification is passed.

An embodiment of the present invention provides a service processing device, which is applied to the kernel layer and includes:

The receiving unit is used to receive the message sent by the application layer;

The processing unit is configured to verify the received message, and execute the file processing command included in the message that the application layer has no authority to execute when the verification is passed.

An embodiment of the present invention provides a business processing device, which is applied in the application layer, including:

an acquisition unit, configured to acquire the first message verification code;

A building unit, configured to form a message according to the first message verification code and the file processing command executed by the application layer without permission, wherein the header of the message is the encrypted first message verification Code, the message body of the message is a file processing command that the application layer has no authority to execute;

A sending unit, configured to send the message to the kernel layer through a socket communication protocol.

In the embodiment of the present invention, when the application program layer in the Android operating system does not have the file processing command executed by authority, the message generated by the file processing command is sent to the kernel layer, and the kernel layer has the highest authority. Like this, the kernel layer receives the message After the file, the message is verified, and when the verification is passed, the file processing command included in the message that the application layer has no authority to execute is executed. Therefore, only the application program layer with system authority can process system files through the kernel layer with root authority, so as to improve the file processing capability of the Android operating system. Moreover, all system files are only processed by the kernel layer, and the private data of each application program is still isolated separately, ensuring the security of the operating system.

Description of drawings

Fig. 1 is the flowchart of file processing in the embodiment of the present invention;

Fig. 2 is the architecture diagram of the file processing system in the embodiment of the present invention;

3 is a structural diagram of a file processing device in a kernel layer in an embodiment of the present invention;

FIG. 4 is a structural diagram of an application layer file processing device in an embodiment of the present invention.

detailed description

In the embodiment of the present invention, the linux kernel layer of the Android operating system, that is, the kernel layer, has root authority and can process system files. In this way, when the program of the application layer of the Android operating system needs to process system files, because it does not have root authority, the task must be sent to the kernel layer, and the task is executed by the kernel layer. Therefore, while ensuring the security of the system, the file processing capability is improved.

In the embodiment of the present invention, when the application program in the Android operating system needs to perform some operations on system files, such as copying or modifying file content and attributes under the system directory, configuring network addresses, etc., since the application program only has system permissions, it cannot To perform these operations, these file processing commands without permission must be sent to the kernel layer for execution, that is, only the application layer with system permission can process system files through the kernel layer with root permission.

Referring to Figure 1, the process of file processing in the Android operating system includes:

Step 101: the application program layer sends a message to the kernel layer, and the message includes a file processing command that the application program layer does not have permission to execute.

Before the application layer executes the file processing command, it can judge whether there is authority to execute the file processing command. When it is determined that there is no authority to execute the file processing command, it sends a message to the kernel layer. The application layer included in the message has no Permissions to execute file processing commands.

Here, the application layer may directly send a message carrying a file processing command to the kernel layer. It is also possible to assemble a secure message and then send it. The specific process includes:

Obtain the first message verification code, and construct a message according to the first message verification code and the file processing command that the application layer has no authority to execute, and finally, send the message to the kernel layer through the socket communication protocol. Wherein, the packet header of the message is the encrypted first message verification code, and the message body of the message is a file processing command that the application layer has no authority to execute.

The first message verification code can be obtained through the user interface of the application program layer, or the first message verification code is obtained from the storage unit of the system, and then the first message verification code is encrypted, and the encrypted second message verification code is encrypted. A message verification code is used as the header of the message, and the file processing command that the application layer has no authority to execute is used as the message body of the message, and then the message is sent to the kernel layer through the socket communication protocol.

In addition, in the embodiment of the present invention, the file processing command can also be directly encrypted using the message verification code to generate a message and send the message to the kernel layer.

Step 102: The kernel layer receives the message sent by the application layer.

Various communication protocols can be used between the kernel layer and the application layer. For example: in step 101, the application program layer sends the message to the kernel layer through the socket communication protocol. Here, the kernel layer monitors the socket port and receives the message sent by the application program layer through the socket port. Of course, the embodiment of the present invention also includes other communication protocols, for example, sharing files, message mailboxes, and the like.

Step 103: The kernel layer verifies the received message, and if the verification is passed, execute step 104; otherwise, the process ends.

In the embodiment of the present invention, only the packet header of the message, or only the message body of the message, or both the packet header and the message body of the message may be verified. in,

When verifying the packet header of the message, the method of building the message is different, and the verification process of the message by the kernel layer is also different, that is, the decryption protocol in the verification process is consistent with the encryption protocol in the process of building the message. For example, the packet header of the packet is encrypted, and the verification process includes:

Decrypt the packet header of the received message to obtain the second message verification code, compare the second message verification code with the saved first message verification code, and verify the packet header of the message when the two are consistent Pass; otherwise, validation fails.

In the embodiment of the present invention, the authority can be released to the kernel layer, that is, all file processing commands can be executed. Therefore, here, there is no need to verify the message body of the message. When the verification of the header of the message is passed, that is Step 104 can be executed; otherwise, the process ends.

In another embodiment of the present invention, it is also possible to only partially open the authority to the kernel layer, that is, the kernel layer can only execute part of the file processing command, therefore, the executable file processing command is preserved in the kernel layer, and the header verification of the message is performed. After passing, the message body of the message needs to be verified. The specific process includes:

The kernel layer checks whether there is a file processing command in the message body of the received message among the stored executable file processing commands; if so, it is determined that the message is a legal message, and step 104 is executed; otherwise, the process ends. In this way, only part of the permission is opened to the kernel layer, which further improves the security of the operating system.

Of course, in another embodiment of the present invention, only the message body of the message can be verified, that is, the kernel layer searches for the file processing command in the message body of the received message in the stored executable file processing command ; If yes, determine that the message is a legal message, and execute step 104, otherwise, the process ends.

Step 104: The kernel layer executes the file processing command included in the message that the application layer has no authority to execute, and the file processing process ends.

After the kernel layer passes the verification of the received message, it can execute the file processing command that the application layer in the message body of the message does not have permission to execute, so as to realize the file processing.

In the embodiment of the present invention, the kernel layer can execute file processing commands that the application layer program does not have permission to execute by calling the execve(constchar*filename, char*constargv[], char*constenvp[]) function.

In the above file processing process, the application layer in the Android operating system can operate the system files through the kernel layer, which improves the file processing capability of the Android operating system. At the same time, all system files are only processed by the kernel layer, and the private data of each application program is still isolated separately, ensuring the security of the operating system.

In the embodiment of the present invention, the kernel layer of the Android operating system must have the highest authority. Therefore, before the kernel layer receives the message sent by the application layer, the kernel layer needs to be activated so that the kernel layer has the highest authority. Generally, when a terminal using an Android operating system is turned on, the kernel layer of the Android operating system is activated. Here, a service myserver can be defined in the init.rc file of the Android operating system, and the executable program server compiled by the kernel layer can be placed in the /system/bin directory, and the kernel layer program server can be defined as the service to be run, as follows :

servicemyserver/system/bin/server

In this way, myserver has root authority. Since the init.rc file is called by the system when the Android operating system is installed, the service myserver will be created every time the system is turned on.

All terminals using the Android operating system can process files through the above method. For example: the home information terminal using the Android operating system performs network address configuration through the above method. After the network address configuration module of the application layer obtains the IP address, subnet mask, gateway address and DNS input by the end user, the configuration module forms them into the message body of the message, and obtains the message verification code for encryption. Use the encrypted verification code as the packet header of the message, communicate with the server at the kernel layer, and send the message to the server at the kernel layer.

After receiving the message, the server at the kernel layer parses and verifies the message. If it is a legal message, it obtains relevant information such as the IP address and subnet mask in the message body, and calls the command to configure the network to configure the network. configuration. In this way, the configuration of the network address at the application layer is realized, that is, the processing of the system file is realized.

Wherein, when the kernel layer has full authority, the server of the kernel layer can only verify the packet header of the message. If the kernel layer has only partial authority, at this time, after verifying the packet header of the packet, the server at the kernel layer needs to determine whether the command for configuring the network can be executed, that is, check whether there is a command for configuring the network in the saved executable commands. If yes, obtain relevant information such as the IP address and subnet mask in the message body, and perform network configuration. Otherwise, return the instruction of illegal message.

It can be seen that in the embodiment of the present invention, when the application program needs to perform some operations on the system files, such as copying or modifying file content and attributes to the system directory, configuring the network address, etc., although the application program only has the system authority, the application program The program can perform these operations through the kernel layer with root authority, so as to improve the file processing capability of the Android operating system.

Through the above file processing method, it can be known that the file processing system in the embodiment of the present invention, referring to FIG. 2 , includes: an application layer 100 and a kernel layer 200, wherein,

The application layer 100 is configured to send a message to the kernel layer 200 .

The kernel layer 200 is used to receive the message and verify the received message, and execute the file processing command included in the message that the application layer 100 has no authority to execute when the verification is passed.

In this system, the application program layer 100 is specifically used to obtain the first message verification code, according to the first message verification code and the file processing command that the application program layer has no authority to execute, to form a message, and through the socket communication protocol, the The message is sent to the kernel layer, wherein the packet header of the message is the encrypted first message verification code, and the message body of the message is a file processing command that the application layer has no authority to execute.

The kernel layer 200 is specifically used to monitor the socket port, receive the message sent by the application program layer through the socket port, decrypt the packet header of the received message, obtain the second message verification code, and save the second message verification code with the compare the verification codes of the first message, and when the two are consistent, the packet header of the message is verified, and the file processing command included in the message that the application layer has no authority to execute is executed.

In the embodiment of the present invention, there are multiple ways for the application program layer 100 to construct a message, and the kernel layer 200 also has multiple verification processes for the message. Generally, the encryption protocol in the process of program layer 100 building a message is verified by the kernel layer 200. The decryption protocol of the process is consistent.

In addition, there may be various communication protocols between the application program layer 100 and the kernel layer 200, and are not limited to socket communication protocols.

The kernel layer 200 can execute all file processing commands, or the kernel layer 200 can only have partial authority, and can only execute part of the file processing commands.

When the kernel layer 200 only has partial authority, it is specifically used to find whether there is a file processing command in the message body of the message in the stored executable file processing command, and if so, determine that the message is legal message.

The file processing system further includes activation means for activating the kernel layer so that the kernel layer has the highest authority.

In the above-mentioned operating system, the apparatus applied to file processing in the kernel layer, referring to FIG. 3 , includes: a receiving unit 310 and a processing unit 320 .

The receiving unit 310 is configured to receive a message sent by the application layer.

The processing unit 320 is configured to verify the received message, and execute the file processing command included in the message that the application layer does not have permission to execute when the verification is passed.

Wherein, the receiving unit 310 is specifically configured to monitor the socket port, and receive the message sent by the application program layer through the socket port.

The processing unit 320 is specifically configured to decrypt the packet header of the received message to obtain a second message verification code, and compare the second message verification code with the stored first message verification code, and when both If it is consistent, the verification is passed, and the file processing command included in the message that the application layer does not have permission to execute is executed.

The processing unit 320 is specifically configured to find out whether there is a file processing command in the message body of the message in the stored executable file processing commands, and if so, determine that the message is a legal message.

In the above-mentioned operating system, the apparatus applied to file processing in the application layer, referring to FIG. 4 , includes: an acquisition unit 410 , an assembly unit 420 , and a sending unit 430 .

The obtaining unit 410 is configured to obtain the first message verification code.

The building unit 420 is used to form a message according to the first message verification code and the file processing command that the application layer has no authority to execute, wherein the packet header of the message is the encrypted first message verification code, and the packet header of the message is the encrypted first message verification code. The message body is a file processing command that the application layer does not have permission to execute.

The sending unit 430 is configured to send the message to the kernel layer through the socket communication protocol.

All the above-mentioned embodiments are described with the Android operating system as an example, but the embodiment of the present invention is not limited thereto, and all operating systems based on the Linux kernel layer can be applied to all of the above-mentioned embodiments, for example: Symbian system.

In the embodiment of the present invention, when the application program layer in the operating system based on the Linux kernel layer has no authority to execute the file processing command, the file processing command generates a message and sends it to the kernel layer, and the kernel layer has the highest authority. Like this, the kernel After the layer receives the message, it verifies the message, and when the verification is passed, executes the file processing command included in the message that the application layer has no authority to execute. In this way, in the operating system based on the Linux kernel layer, only the application program layer with system authority can operate the system files through the kernel layer with root authority, which improves the file processing capability of the operating system based on the Linux kernel layer. At the same time, all system files are only processed by the kernel layer, and the private data of each application program is still isolated separately, ensuring the security of the operating system.

Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.

Claims (12)

1. A file processing method is applied to an Android operating system and is characterized by comprising the following steps:

the kernel layer receives a message sent by the application program layer;

the kernel layer verifies the received message, and executes a file processing command which is not authorized to be executed by the application program layer and is included in the message when the message passes the verification; wherein the sending of the message by the application layer comprises:

acquiring a first message verification code;

according to the first message verification code and the file processing command which is not executed by the application program layer in the permission, a message is established, wherein the packet header of the message is the encrypted first message verification code, and the message body of the message is the file processing command which is not executed by the application program layer in the permission;

and sending the message to the kernel layer through a socket communication protocol.

2. The method of claim 1, wherein the kernel layer receiving the message sent by the application layer comprises:

and the kernel layer monitors a socket port and receives the message sent by the application program layer through the socket port.

3. The method of claim 1, wherein the kernel layer validating the received message comprises:

decrypting the packet header of the received message to obtain a second message verification code;

and comparing the second message verification code with the stored first message verification code, and when the second message verification code is consistent with the stored first message verification code, verifying the packet header of the message.

4. The method of claim 1 or 3, wherein the kernel layer validating the received message comprises:

searching whether a file processing command in the message body of the message exists in the stored executable file processing command;

and if so, determining that the message is a legal message.

5. The method of claim 1, wherein before the kernel layer receives the message sent by the application layer, the method further comprises:

and activating the inner core layer to enable the inner core layer to have the highest authority.

6. A file processing system is applied to an Android operating system and is characterized by comprising: an application layer and a kernel layer, wherein,

the application program layer is used for sending messages to the kernel layer;

the kernel layer is used for receiving the message, verifying the received message and executing a file processing command which is contained in the message and is not authorized to be executed by the application program layer when the verification is passed;

the application program layer is specifically configured to obtain a first message authentication code, construct a message according to the first message authentication code and a file processing command that the application program layer does not have an authority to execute, and send the message to the kernel layer through a socket communication protocol, where a packet header of the message is the encrypted first message authentication code, and a message body of the message is the file processing command that the application program layer does not have the authority to execute.

7. The system of claim 6,

the kernel layer is specifically configured to monitor a socket port, receive a packet sent by the application layer through the socket port, decrypt a packet header of the received packet to obtain a second packet verification code, compare the second packet verification code with the stored first packet verification code, and when the second packet verification code is consistent with the stored first packet verification code, verify the packet header of the packet, and execute a file processing command that the application layer does not have an authority to execute, included in the packet.

8. The system of claim 7,

the kernel layer is specifically configured to search for whether a file processing command in the message body of the message exists in the stored executable file processing commands, and if so, determine that the message is a legal message.

9. The system of claim 6, further comprising:

and the activating device is used for activating the inner core layer to enable the inner core layer to have the highest authority.

10. The device for processing the file is applied to a kernel layer of an Android operating system and comprises the following steps:

the receiving unit is used for receiving the message sent by the application program layer;

the processing unit is used for verifying the received message and executing a file processing command which is not authorized to be executed by the application program layer and is contained in the message when the verification is passed; wherein,

the receiving unit is specifically configured to monitor a socket port, and receive a packet sent by an application layer through the socket port.

11. The apparatus of claim 10,

the processing unit is specifically configured to decrypt a packet header of a received packet to obtain a second packet verification code, compare the second packet verification code with the stored first packet verification code, and if the second packet verification code is identical to the stored first packet verification code, verify the packet header of the packet, and execute a file processing command that the application program layer does not have an authority to execute, included in the packet.

12. The apparatus of claim 10,

the processing unit is specifically configured to search for whether a file processing command in the message body of the message exists in the stored executable file processing commands, and if so, determine that the message is a legal message.