mirror of https://github.com/0intro/libelf
104 lines
1.9 KiB
Markdown
104 lines
1.9 KiB
Markdown
[](https://github.com/0intro/libelf/actions/workflows/c.yml)
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[](https://scan.coverity.com/projects/0intro-libelf)
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libelf
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======
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Libelf is a simple library which provides functions to read ELF files.
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Headers
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-------
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```
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#include <stdint.h>
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#include <elf.h>
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```
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Structures
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----------
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```
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typedef struct Fhdr Fhdr;
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/*
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* Portable ELF file header
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*/
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struct Fhdr {
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/* Private */
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...
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/* ELF Identification */
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uint8_t class; /* File class */
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uint8_t data; /* Data encoding */
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uint8_t elfversion; /* File version */
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uint8_t osabi; /* Operating system/ABI identification */
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uint8_t abiversion; /* ABI version */
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/* ELF Header */
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uint16_t type;
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uint16_t machine;
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uint32_t version;
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uint64_t entry;
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uint64_t phoff;
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uint64_t shoff;
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uint16_t ehsize; /* ELF Header size */
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uint16_t phentsize; /* Section Header size */
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uint16_t phnum;
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uint16_t shentsize; /* Program Header size */
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uint16_t shnum;
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uint16_t shstrndx;
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/* Section Header */
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uint32_t name;
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uint64_t offset;
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uint64_t size;
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/* String Table */
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uint32_t strndxsize; /* String Table Size */
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uint8_t *strndx; /* Copy of String Table */
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};
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```
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Functions
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---------
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```
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/* Read */
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int readelf(FILE *f, Fhdr *fp);
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uint8_t* readelfsection(FILE *f, char *name, uint64_t *size, Fhdr *fp);
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void freeelf(Fhdr *fp);
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/* Print */
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void printelfhdr(Fhdr *fp);
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/* String */
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char* elfclass(uint8_t class);
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char* elfdata(uint8_t data);
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char* elfosabi(uint8_t osabi);
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char* elftype(uint16_t type);
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char* elfmachine(uint16_t machine);
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char* elfversion(uint8_t version);
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```
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Example
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-------
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```
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Fhdr fhdr;
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FILE *f;
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uint8_t *buf;
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uint64_t len;
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f = fopen("/bin/ls", "rb");
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if (f == NULL)
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return -1;
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buf = readelfsection(f, ".text", &len, &fhdr);
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if (buf == NULL)
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return -1;
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// ...
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freeelf(&fhdr);
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```
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