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ELF Parser Project
What are the available APIs?

What are the available APIs?

This file includes all the internal APIs that does the heavy lifting.

core_api/parser.h
#ifndef PARSER_H
#define PARSER_H

#include <stdio.h>
#include <elf.h>

typedef struct {
  Elf64_Ehdr* ehdr;         // File Header
  Elf64_Phdr* phdrs;        // Program Headers
  Elf64_Shdr* shdrs;        // Section Headers

  char* r_shstrtab;         // flat section header string table dump
  int r_shstr_count;        // └─ count of total bytes

  char** f_shstrtab;        // formatted dump of section header string table
  int f_shstr_count;        // └─ count of total individual entries

  char* r_strtab;           // flat string table dump
  int r_str_count;          // └─ count of total bytes

  char** f_strtab;          // formatted dump of string table
  int f_str_count;          // └─ count of total individual entries

  Elf64_Sym* symtab;        // Symbol Table
  int symtab_count;         // └─ entry count

  Elf64_Sym* dynsym;        // Dynamic Symbol Table
  int dynsym_count;         // └─ entry count

  Elf64_Rela* reladyn;      // .rela.dyn Table
  int reladyn_count;        // └─ entry count

  Elf64_Rela* relaplt;      // .rela.plt Table
  int relaplt_count;        // └─ entry count

  char* r_dynstr;           // flat .dynstr dump
  int r_dstr_count;         // └─ count of total bytes

  char** f_dynstr;          // formatted dump of .dynstr table
  int f_dstr_count;         // └─ count of total individual entries

  Elf64_Dyn* dynamic;       // Dynamic Section
  int dyn_ent;              // └─ entry count
} ElfFile;

int verify_elf(FILE* f_obj);
int parse_ehdr(FILE* f_obj, ElfFile* AccessFile);
int parse_phdrs(FILE* f_obj, ElfFile* AccessFile);
int parse_shdrs(FILE* f_obj, ElfFile* AccessFile);
int parse_shstrtab(FILE* f_obj, ElfFile* AccessFile);
int parse_strtab(FILE* f_obj, ElfFile* AccessFile);
int parse_symtab(FILE* f_obj, ElfFile* AccessFile);
int parse_dynsym(FILE* f_obj, ElfFile* AccessELF);
int parse_relocations(FILE* f_obj, ElfFile* AccessELF);
int parse_dynstr(FILE* f_obj, ElfFile* AccessELF);
int parse_dynamic(FILE* f_obj, ElfFile* AccessELF);
int deallocator(ElfFile* AccessELF);

#endif

The data type structs, like Elf64_Ehdr are borrowed from elf.h header file.

The ElfFile is the actual API that would be out for external use.

The idea is that the main controller would open the ELF file to be parsed and it will pass the file pointer to each of these APIs, along with a ElfFile struct. Every API will populate its pointer and it can be used later.

The idea behind ElfFile struct is that it will be the one stop solution for all the extracted parts from the ELF. It really simplifies the access to different parts of the ELF just by one struct.

In the end, deallocator is called to free up the memory.

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