elf32.h

/*
 * @file elf32.h
 * @brief Standard ELF32 structures definitions
 *
 * @see https://docs.oracle.com/cd/E23824_01/html/819-0690/chapter6-46512.html
 *
 * TODO: relocation
 */
 
#ifndef ELF32_H
#define ELF32_H
 
#include <stdint.h>
 
typedef uint16_t elf32_half;
typedef uint32_t elf32_word;
typedef int32_t elf32_sword;
typedef uint32_t elf32_off;
typedef uint32_t elf32_addr;
 
struct elf32_ehdr {
    uint8_t e_ident[16];
    elf32_half e_type;      
    elf32_half e_machine;   
    elf32_word e_version;   
    elf32_word e_entry;     
    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;  
};
 
typedef enum {
    EI_MAG0 = 0,       // 0x7F
    EI_MAG1 = 1,       // 'E'
    EI_MAG2 = 2,       // 'L'
    EI_MAG3 = 3,       // 'F'
    EI_CLASS = 4,      // Architecture (32/64)
    EI_DATA = 5,       // Byte Order
    EI_VERSION = 6,    // ELF Version
    EI_OSABI = 7,      // OS Specific
    EI_ABIVERSION = 8, // OS Specific
    EI_PAD = 9,        // Padding
    EI_NIDENT = 16,
} e_ident;
 
typedef enum {
    ET_NONE = 0, 
    ET_REL = 1,  
    ET_EXEC = 2, 
    ET_DYN = 3,  
    ET_CORE = 4  
} e_type;
 
typedef enum {
    EI_MAG_0 = 0x7f,
    EI_MAG_1 = 'E',
    EI_MAG_2 = 'L',
    EI_MAG_3 = 'F',
} ei_mag;
 
typedef enum {
    EI_CLASS_32 = 1, 
    EI_CLASS_64 = 2, 
} ei_class;
 
typedef enum {
    EI_DATA_LSB = 1, 
    EI_DATA_MSB = 2, 
} ei_data;
 
typedef enum {
    EM_NONE = 0, 
    EM_386 = 3,  
} e_machine;
 
/***/
typedef enum {
    EV_NONE = 0,    
    EV_CURRENT = 1, 
} e_version;
 
struct elf32_shdr {
    elf32_word sh_name; 
    elf32_word sh_type; 
    elf32_word sh_flags; 
    elf32_addr sh_addr;  
    elf32_off sh_offset; 
    elf32_word sh_size;  
    elf32_word sh_link;
    elf32_word sh_info;
    elf32_word sh_addralign; 
    elf32_word sh_entsize;
};
 
typedef enum {
    SHN_UNDEF = 0, 
} sh_index;
 
typedef enum {
    SHT_NULL = 0,     
    SHT_PROGBITS = 1, 
    SHT_SYMTAB = 2,   
    SHT_STRTAB = 3,   
    SHT_RELA = 4,     
    SHT_NOBITS = 8,   
    SHT_REL = 9,      
} sh_type;
 
typedef enum {
    SHF_WRITE = 0x1,           
    SHF_ALLOC = 0x2,           
    SHF_EXECINSTR = 0x4,       
    SHF_MASKPROC = 0xf0000000, 
} sh_flags;
 
struct elf32_sym {
    elf32_word st_name; 
    elf32_addr st_value;   
    elf32_word st_size;    
    unsigned char st_info; 
    unsigned char st_other; 
    elf32_half st_shndx;    
};
 
#define ELF32_ST_BIND(info) ((info) >> 4)
#define ELF32_ST_TYPE(info) ((info)&0xf)
#define ELF32_ST_INFO(bind, type) (((bind) << 4) | ((type)&0xf))
 
typedef enum {
    STB_LOCAL = 0,  
    STB_GLOBAL = 1, 
    STB_WEAK = 2, 
} st_bind;
 
typedef enum {
    STT_NOTYPE = 0,  
    STT_OBJECT = 1,  
    STT_FUNC = 2,    
    STT_SECTION = 3, 
    STT_FILE = 4,    
} st_type;
 
struct elf32_phdr {
    elf32_word p_type;   
    elf32_off p_offset;  
    elf32_addr p_vaddr;  
    elf32_addr p_paddr;  
    elf32_word p_filesz; 
    elf32_word p_memsz;  
    elf32_word p_pflags; 
    elf32_word p_align;  
};
 
typedef enum {
    PT_NULL = 0,    
    PT_LOAD = 1,    
    PT_DYNAMIC = 2, 
    PT_INTERP = 3,  
    PT_NOTE = 4,    
    PT_SHLIB = 5,   
    PT_PHDR = 6,    
} p_type;
 
typedef enum {
    PF_X = 0x1, 
    PF_W = 0x2, 
    PF_R = 0x4, 
} p_flags;
 
#endif /* ELF32_H */