matos/core/elf.h

#pragma once

#include "process.h"
#include "thread.h"
#include "types.h"

/**
 * Typedefs, constants and structure definitions as given by the ELF
 * standard specifications.
 */
typedef unsigned long Elf32_Addr;
typedef unsigned long Elf32_Word;
typedef unsigned short Elf32_Half;
typedef unsigned long Elf32_Off;
// typedef signed long Elf32_Sword;

/**
 * ELF 32-bit format related structures.
 * See http://www.cs.cmu.edu/afs/cs/academic/class/15213-f00/docs/elf.pdf
 */

#define SHT_NULL 0
#define SHT_PROGBITS 1
#define SHT_SYMTAB 2
#define SHT_STRTAB 3
#define SHT_RELA 4
#define SHT_HASH 5
#define SHT_DYNAMIC 6
#define SHT_NOTE 7
#define SHT_NOBITS 8
#define SHT_REL 9
#define SHT_SHLIB 10
#define SHT_DYNSYM 11
#define SHT_LOPROC 0x70000000
#define SHT_HIPROC 0x7fffffff
#define SHT_LOUSER 0x80000000
#define SHT_HIUSER 0xffffffff


/** ELF Header **/
#define EI_NIDENT 16
typedef struct {
    unsigned char e_ident[EI_NIDENT];
    Elf32_Half e_type;
    Elf32_Half e_machine;
    Elf32_Word e_version;
    Elf32_Addr 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;
} __attribute__((packed)) Elf32_Ehdr_t;

/** ELF Section header */
typedef struct {
    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;
} __attribute__((packed)) Elf32_Shdr_t;

/** ELF Symbol **/
typedef struct {
    Elf32_Word st_name;
    Elf32_Addr st_value;
    Elf32_Word st_size;
    unsigned char st_info;
    unsigned char st_other;
    Elf32_Half st_shndx;
} __attribute__((packed)) Elf32_Sym_t;

/** ELF Program header **/
typedef struct {
    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_flags;
    Elf32_Word p_align;
} __attribute__((packed)) Elf32_Phdr_t;

#define ELF_SYM_TYPE(info) ((info) & 0xf)
#define ELF_SYM_TYPE_FUNC  0x2


uaddr_t loadElfProg(const char *prog, struct process *proc);