ELF FIle Format

- 목적파일 구조는 8-비트 와 32비트 구조를 가진 다양한 CPU들을 지원한다.

    Size  Alignment        Purpose

Elf32_Addr    4    4    Unsigned program address

Elf32_Half     2    2     Unsigned medium integer

Elf32_Off       4    4    Unsigned file offset

Elf32_Sword   4   4    Signed large integer

Elf32_Word    4    4    Unsigned large integer

unsgined char   1 1  unsgined small integer

 

 

include/uapi/linux/elf.h

/* 32-bit ELF base types. */ typedef __u32 Elf32_Addr; typedef __u16 Elf32_Half; typedef __u32 Elf32_Off; typedef __s32 Elf32_Sword; typedef __u32 Elf32_Word; /* 64-bit ELF base types. */ typedef __u64 Elf64_Addr; typedef __u16 Elf64_Half; typedef __s16 Elf64_SHalf; typedef __u64 Elf64_Off; typedef __s32 Elf64_Sword; typedef __u32 Elf64_Word; typedef __u64 Elf64_Xword; typedef __s64 Elf64_Sxword;

 

 

#define EI_NIDENT 16 typedef struct elf32_hdr{ unsigned char e_ident[EI_NIDENT]; Elf32_Half e_type; Elf32_Half e_machine; Elf32_Word e_version; Elf32_Addr e_entry; /* Entry point */ Elf32_Off e_phoff; Elf32_Off e_shoff; Elf32_Word e_flags; Elf32_Half e_ehsize; Elf32_Half e_phentsize; Elf32_Half e_phnum; Elf32_Half e_shentsize; Elf32_Half e_shnum; Elf32_Half e_shstrndx; } Elf32_Ehdr; typedef struct elf64_hdr { unsigned char e_ident[EI_NIDENT]; /* ELF "magic number" */ Elf64_Half e_type; Elf64_Half e_machine; Elf64_Word e_version; Elf64_Addr e_entry; /* Entry point virtual address */ Elf64_Off e_phoff; /* Program header table file offset */ Elf64_Off e_shoff; /* Section header table file offset */ Elf64_Word e_flags; Elf64_Half e_ehsize; Elf64_Half e_phentsize; Elf64_Half e_phnum; Elf64_Half e_shentsize; Elf64_Half e_shnum; Elf64_Half e_shstrndx; } Elf64_Ehdr;