CN108491197A - A kind of in-orbit maintenance injection code generating method of the spacecraft compiled based on same platform combination - Google Patents

Abstract

A method for generating injection codes for spacecraft on-orbit maintenance based on combined compilation on the same platform, (1) adopting the ERC32 compilation system to restore the status of the spacecraft’s on-orbit operating software, and generating a.out format on-orbit status object files through one link; ( 2) Use the ERC32 compilation system to preprocess and compile the on-orbit maintenance source code to generate the corresponding assembly code target file; (3) use the RCC compilation system to assemble the assembly code target file to generate an intermediate target file to be uploaded; ( 4) converting the on-orbit state object file into an on-orbit state intermediate object file in ELF format; (5) streamlining the on-orbit state intermediate object file; (6) creating a new link script file; (7) generating a new executable object file; (8) Convert the new executable object file into a link instruction file or a BIN file through the RCC compilation system, and directly extract the injection code instruction specifying the starting address, thereby completing the generation of the spacecraft maintenance injection code.

Description

A Method of Injection Code Generation for Spacecraft On-orbit Maintenance Based on Compilation on the Same Platform

technical field

The invention belongs to the field of on-orbit maintenance of spacecraft, and is aimed at but not limited to a method for generating injection codes for on-orbit maintenance of spacecraft software in a sparc architecture.

Background technique

The on-orbit maintenance capability of the spacecraft software is an indispensable means to ensure the long life of the spacecraft. Compared with the redundant backup of hardware, this method is more economical and more flexible. The method of improving the long life and high reliability of spacecraft on-orbit operation through software on-orbit maintenance has been paid more and more attention.

At present, the main processor platform of my country's spacecraft in orbit is the sparc series architecture, specifically, the sparc V7 architecture and the sparc V8 architecture. The main means of on-orbit operation and maintenance of spacecraft is to implement software on-orbit maintenance. The maintenance of the spacecraft’s on-orbit software is mainly based on the hook function method, that is, an on-orbit maintenance injection code is injected on the writable storage injection area. When the on-orbit maintenance is enabled, the hook function jumps to the injection through the specified address. After execution, return to the original on-orbit software to continue execution. In this application scenario, the generation of on-orbit maintenance injection code is a key link in software on-orbit maintenance, and it is also a relatively difficult task. Since the sparc V8 architecture processor platform uses the RCC (RTEMS Cross Compilation System) cross compiler, the object file generated by the RCC compiler is in ELF format, and supports compilation and linking based on the "section" attribute, which is convenient for setting the "section" attribute. Set the starting address of the injection area, and use the method of secondary linking (patent applied for: a method for generating injection codes for spacecraft on-orbit maintenance based on secondary links, 201710476446.5) to realize the generation of on-orbit maintenance injection codes. The sparc V7 architecture processor platform generally uses the ERC32 cross compiler. The object file generated by the compiler system is in the a.out format, and does not support compilation links based on the "section" attribute, and cannot directly use the secondary link method. Realize the generation of injection code for on-orbit maintenance. Previously, for the spacecraft software using the ERC32 cross-compiler, the generation of the on-orbit maintenance injection code was mainly by analyzing the original on-orbit software and the compilation result files of the on-orbit maintenance software, and sorting out all the on-orbit maintenance instruction codes that need to be re-written. Locate the information and complete the relocation. This process is relatively complicated. On the one hand, it requires proficiency in the file format of the compilation result and the ability to sort out all relocation information; on the other hand, it requires a deeper understanding of the command rule set and the ability to relocate the on-orbit maintenance command code.

Contents of the invention

The technical problem of the present invention is to overcome the deficiencies of the prior art and provide a method for generating injection codes for on-orbit maintenance of spacecraft based on the same platform combination compilation.

The technical solution of the present invention is: a method for generating injection codes for on-orbit maintenance of spacecraft based on the combined compilation of the same platform, which is realized in the following manner:

(1) Use the ERC32 compilation system to restore the status of the spacecraft’s on-orbit software, and generate the a.out format on-orbit status object file through a link;

(2) Write the on-orbit maintenance source code, use the ERC32 compilation system to preprocess and compile the on-orbit maintenance source code, and generate the corresponding assembly code target file;

(3) use the RCC compilation system to assemble the assembly code target file generated in step (2), and generate an intermediate target file to be uploaded;

(4) the a.out format on-track state target file generated in the step (1) is converted into the on-track state intermediate target file of the ELF format through target file format conversion;

(5) streamline the on-orbit state intermediate object file of the ELF format generated in step (4), remove information irrelevant to the link relocation process;

(6) Create a link script file;

(7) Based on the link script file established in step (6), use the RCC compilation system to perform a secondary process on the simplified in-orbit state intermediate object file, the intermediate object file to be uploaded, and the corresponding static library file described in step (5). link to generate a new executable object file;

(8) convert the new executable target file generated in step (7) into a link instruction file or a BIN file by the RCC compilation system, and directly extract the injection code instruction of the specified starting address from the link instruction file or the BIN file, thereby Complete the generation of injection codes for spacecraft on-orbit maintenance.

Further, in step (1), by using the same sparc platform ERC32 compilation system as the original on-orbit software of the spacecraft, the original on-orbit software source file directory is compiled and linked to generate the a.out format on-orbit status target file.

Further, the storage path of the on-orbit maintenance source code is in the injected code source file of the new on-orbit maintenance under the original on-orbit software source file directory of the spacecraft.

Further, the RCC compilation system and the ERC32 compilation system used belong to the compilation system under the sparc platform, and the instruction set Φ _ERC32 compiled by the ERC32 compilation system is a subset of the instruction set Φ _RCC compiled by the RCC compilation system, namely

Further, the step (4) converts the a.out format on-track status target file generated in step (1) to the a.out format on-track status target file by using the target file format conversion tool that comes with the RCC compilation system. Convert to an in-orbit state intermediate object file in ELF format.

Further, described step (5) utilizes the on-track state intermediate object file of the ELF format generated in step (4), utilizes the file cutting tool strip that the RCC compiling system carries, carries out the on-track state intermediate object file of the ELF format Compact, removing information not relevant to the link relocation process.

Further, described step (6) new link script file is specifically: in the section of script file SECTIONS, according to the address setting of the output section of the original in-track software, create a new first output section space, and create the first output section space of the newly created section The initial address of an output section space is set to the initial address of the output section of the original in-track software, and the input section element of the first output section space of the described new creation is set to a link after being simplified through step (5) file format The generated streamlined in-track state intermediate object file, and then according to the preset start address of the injection area, create a new second output segment space, and set the start address of the second output segment space to the preset injection area The starting address of the area, and the input section element of the second output section space is set as an intermediate target file to be uploaded generated by the on-orbit maintenance software after being combined and compiled on the same platform.

Further, the on-track status target file is an executable target file in a.out file format, the on-track status intermediate target file, the simplified on-track status intermediate target file, and the to-be-uploaded intermediate target file and the new executable object files are in ELF file format.

Further, through the RCC compilation system, use the objdump command to convert the new executable object file a.out in ELF format generated in step (7) into a link instruction file with the extension .lst, or use the objcopy command to convert the step ( 7) The new executable object file a.out of the ELF format that generates in the conversion is the BIN file that extension is called .bin.

Furthermore, the source codes of the spacecraft’s on-orbit operation software and on-orbit maintenance are written in C language.

Compared with the prior art, the present invention has beneficial effects as follows:

(1) The spacecraft on-orbit maintenance injection code generation method based on the combined compilation of the same platform, through the comprehensive utilization of the sparc platform ERC32 and RCC two compilation systems for combined compilation, can ensure the consistency of the instruction set and symbol information of the generated target files Under the premise of this, the on-orbit maintenance software injection code is relocated relative to the address information of the original on-orbit software, which greatly improves the efficiency and correctness of the on-orbit maintenance injection code generation.

(2) The spacecraft on-orbit maintenance injection code generation method based on the combined compilation of the same platform is mainly for the on-orbit spacecraft software that uses the ERC32 compilation system of the sparc platform to generate the on-orbit maintenance injection code. Compared with its original file analysis The method of generating injection code in this way eliminates the restrictions on the writing of on-orbit maintenance codes such as new global variables and new library function calls, and greatly improves the implementation efficiency of on-orbit maintenance source codes.

(3) The spacecraft on-orbit maintenance injection code generation method based on the combined compilation of the same platform, by cutting the on-orbit state intermediate object file in ELF format, the information irrelevant to the link relocation process is removed, and the link process is realized. The magnitude of the target file expands the effective address space for the on-orbit maintenance and relocation of the spacecraft software in the secondary link mode.

(4) This method has been applied in the implementation of on-orbit maintenance for several on-orbit spacecraft software using the sparc platform ERC32 compilation system. The feasibility and effectiveness of this method have been verified by engineering practice, and the on-orbit The maintainability of spacecraft software provides a new method for realizing on-orbit maintenance for the development of subsequent spacecraft software.

Description of drawings

Fig. 1 is the flow chart of the present invention.

Detailed ways

The present invention will be described in detail below in conjunction with the accompanying drawings and examples.

A spacecraft on-orbit maintenance injection code generation method based on same-platform combined compilation of the present invention is mainly oriented to, but not limited to, on-orbit spacecraft software using the sparc platform ERC32 compilation system. The content includes: according to the requirements of the spacecraft software on-orbit maintenance tasks, write the corresponding on-orbit maintenance source code (C language), use two compiler systems under the same sparc platform: ERC32 compilation system and RCC compilation system, for on-orbit maintenance The source code is combined and compiled to generate an intermediate object file to be uploaded, and the intermediate object file is relinked with the executable object file compiled and linked to the original on-orbit software, thereby completing the generation of the spacecraft on-orbit maintenance injection code.

Implementation method of the present invention is as follows:

(1) Use the ERC32 compilation system to restore the status of the spacecraft’s on-orbit software, and generate the a.out format on-orbit status object file through a link;

Specifically: use the ERC32 compilation system of the sparc platform to compile the source file directory of the spacecraft on-orbit software and realize a link. The ERC32 compilation system and the source file directory of the spacecraft on-orbit software must be executable with the spacecraft on-orbit software The state at the time of code generation remains consistent.

(2) Write source code for on-orbit maintenance;

Specifically: in the source file directory of the spacecraft’s on-orbit software, create a new on-orbit maintenance code source file with the extension .c, and write the corresponding on-orbit maintenance source code and required head File.

(3) Use the ERC32 compilation system to preprocess and compile the on-orbit maintenance source code written in step (2) separately, and generate the corresponding assembly code target file. The assembly code target file has the extension of .s or .S;

(4) use the RCC compilation system to assemble the assembly code object file generated in step (3), generate an intermediate object file to be uploaded, and the intermediate object file to be uploaded is the ELF object file format with an extension of .o;

(5) Convert the on-orbit state object file in the a.out format generated in step (1) to an on-orbit state intermediate object file in ELF format through object file format conversion. The object file format conversion tool can automatically use the RCC compilation system It is realized by the object file format conversion tool objcopy;

(6) Cut the on-orbit intermediate object file in ELF format generated in step (5), and remove symbol information, debugging information, and character string information that are not related to the link relocation process, so as to realize lightweight in the link process Target files, to better expand the address space of the effective injection area, and the clipping of target files in the middle of the track state can be realized by using the strip tool that comes with the RCC compilation system;

(7) Create a link script file;

Specifically: create a new link script file, in the section of the new link script file SECTIONS, according to the address setting of the output section of the original in-orbit software of the spacecraft, create a new first output section space, and place the newly created first The initial address of the output section space is set to the initial address of the output section of the spacecraft's former on-orbit software, and the input section element of the first output section space of the new creation is set to a link after the step (6) file is clipped The generated streamlined in-track state intermediate object file, and then according to the preset start address of the injection area, create a new second output segment space, and set the start address of the second output segment space to the preset injection area The starting address of the area, and the input section element of the second output section space is set as an intermediate target file to be uploaded generated by the on-orbit maintenance software after being combined and compiled on the same platform.

(8) Based on the link script file established in step (7), use the RCC compilation system to perform secondary linking on the simplified in-orbit state intermediate object file, the intermediate object file to be uploaded, and the corresponding static library file to generate ELF A new executable object file in the format a.out;

(9) Through the RCC compilation system, use the objdump command to convert the new executable object file a.out in ELF format generated in step (8) into a link instruction file with an extension of .lst, or use the objcopy command to convert the step ( 8) The new executable object file a.out in ELF format generated in 8) is converted into a BIN file with an extension of .bin, and the injection code instruction specifying the starting address is directly extracted from the link instruction file or BIN file generated above, In this way, the generation of injection codes for on-orbit maintenance of the spacecraft is completed.

Example:

(1) On the premise of ensuring that the ERC32 compilation system and source file compilation directory of the spacecraft on-orbit software are consistent with the state of the spacecraft on-orbit software when the executable code is generated, use the ERC32 compiler sparc-rtems-gcc, through the makefile file, The source file compilation directory of the spacecraft on-orbit software is compiled and linked to generate an executable object file a.out in the a.out file format.

(2) In the source file directory of the spacecraft’s on-orbit software, create a new injection code source file task_inject.c for on-orbit maintenance, and write the on-orbit maintenance source code in the task_inject.c source file, as shown in Table 1:

Table 1 Example of source code for on-orbit maintenance

(3) Use the ERC32 compiler sparc-rtems-gcc to preprocess and compile the on-orbit maintenance source code task_inject.c separately, and generate the corresponding assembly code object file task_inject.s.

(4) Use the RCC compiler sparc-rtems-gcc to assemble the assembly code target file task_inject.s generated in step (3), and generate the intermediate target file task_inject.o to be uploaded;

(5) Use the RCC compiler object file format conversion tool sparc-rtems-objcopy to convert the executable object file a.out in the a.out file format generated in step (1) into the on-orbit state intermediate object file a.o in ELF format .

(6) Use the RCC compiler file clipping tool sparc-rtems-strip to clip the in-track state intermediate object file a.o in ELF format generated in step (5), and remove symbolic information, debugging information and String information, generate the streamlined on-orbit intermediate object file a.o.

(7) Create a new link script file linkobsm as a new link script file, as shown in Table 2:

Table 2 Secondary link script file example

(8) Based on the new link script file linkobsm, use the RCC compiler sparc-rtems-gcc to link the simplified in-orbit intermediate object file a.o, the intermediate object file task_inject.o to be uploaded, and the static library files such as the math library , generate a new linked ELF format executable object file a.out;

(9) Use the sparc-rtems-objdump command of the RCC compilation system to convert the new linked ELF format executable object file a.out generated by step (8) into a link instruction file boot.lst with an extension of .lst, Or use the sparc-rtems-objcopy command of the RCC compilation system to convert the new linked ELF format executable object file a.out generated in step (8) into a BIN file boot.bin with an extension of .bin. Directly extract the injection code instruction whose starting address is 0x21a0000 from the above-mentioned generated file boot.lst or boot.bin file, so as to complete the generation of the spacecraft maintenance injection code.

The technical solution of this embodiment uses two compilation systems of the sparc platform: the ERC32 compilation system and the RCC compilation system, to combine and compile the on-orbit maintenance source code, and perform secondary linking with the executable target file compiled by the original on-orbit software. The on-orbit maintenance software injection code is automatically relocated relative to the address information of the original on-orbit software, which greatly improves the efficiency and correctness of the on-orbit maintenance injection code generation.

Parts not described in detail in the present invention belong to the common knowledge of those skilled in the art.

Claims (10)

1. A spacecraft on-orbit maintenance injection code generation method based on the same platform combination compilation is characterized in that it is realized in the following manner: (1) Use the ERC32 compilation system to restore the status of the spacecraft’s on-orbit software, and generate the a.out format on-orbit status object file through a link; (2) Write the on-orbit maintenance source code, use the ERC32 compilation system to preprocess and compile the on-orbit maintenance source code, and generate the corresponding assembly code target file; (3) use the RCC compilation system to assemble the assembly code target file generated in step (2), and generate an intermediate target file to be uploaded; (4) the a.out format on-track state target file generated in the step (1) is converted into the on-track state intermediate target file of the ELF format through target file format conversion; (5) streamline the on-orbit state intermediate object file of the ELF format generated in step (4), remove information irrelevant to the link relocation process; (6) Create a link script file; (7) Based on the link script file established in step (6), use the RCC compilation system to perform a secondary process on the simplified in-orbit state intermediate object file, the intermediate object file to be uploaded, and the corresponding static library file described in step (5). link to generate a new executable object file; (8) convert the new executable target file generated in step (7) into a link instruction file or a BIN file by the RCC compilation system, and directly extract the injection code instruction of the specified starting address from the link instruction file or the BIN file, thereby Complete the generation of injection codes for spacecraft on-orbit maintenance. 2. method according to claim 1, it is characterized in that: in the step (1), by using the same sparc platform ERC32 compiling system with the original on-orbit software of the spacecraft, the original on-orbit software source file directory is compiled and linked to generate a.out format on-orbit state object file. 3. The method according to claim 1, characterized in that: the on-orbit maintenance source code storage path is in the newly-created on-orbit maintenance injection code source file under the original on-orbit software source file directory of the spacecraft. 4. the method according to claim 1 is characterized in that: used RCC compilation system and ERC32 compilation system belong to the compilation system under the sparc platform together, and the instruction set Φ _ERC32 that ERC32 compilation system compiles and generates is that RCC compilation system compiles The generated instruction set Φ is a subset of _RCC , namely 5. The method according to claim 1, characterized in that: said step (4) utilizes the target file format conversion carried by the RCC compiling system to convert the a.out format on-track state target file generated in step (1) Tool to convert a.out format on-orbit state object file to ELF format on-orbit state intermediate object file. 6. the method according to claim 1 is characterized in that: described step (5) utilizes the file clipping tool strip that RCC compilation system carries with the on-track state intermediate object file of the ELF format that generates in step (4) , streamline the on-track state intermediate object file in ELF format, and remove information irrelevant to the link relocation process. 7. The method according to claim 1, characterized in that: said step (6) newly-built link script file, specifically: in the script file SECTIONS section, according to the address setting of the output section of the original in-track software, newly-created The first output segment space, the initial address of the first output segment space of the new creation is set to the initial address of the output segment of the original in-track software, and the input segment element of the first output segment space of the new creation is set to After a link, the streamlined in-track state intermediate object file generated after the file format streamlining in step (5), and then according to the pre-set initial address of the injection area, create a second output segment space, and the second output segment The start address of the space is set to the preset start address of the injection area, and the input segment element of the second output segment space is set to be an intermediate object file to be uploaded generated by the on-orbit maintenance software combined and compiled on the same platform. 8. The method according to claim 1, characterized in that: the on-track state target file is an executable target file in the a.out file format, the on-track state intermediate target file, the simplified on-track The state intermediate object file, the intermediate object file to be uploaded and the new executable object file are all in ELF file format. 9. the method according to claim 1 is characterized in that: by RCC compiling system, use objdump order to convert the new executable target file a.out of the ELF format that generates in step (7) into extension name.lst link instruction file, or use the objcopy command to convert the new executable object file a.out in ELF format generated in step (7) into a BIN file with an extension of .bin. 10. The method according to claim 1, characterized in that: the spacecraft on-orbit operation software and the on-orbit maintenance source code are written in C language.