elf.h

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#pragma once

#include<libtransistor/types.h>
#include<assert.h>
#include<stdint.h>

#ifdef __cplusplus
extern "C" {
#endif

typedef struct {
    int64_t d_tag;
    union {
        uint64_t d_val;
        void *d_ptr;
    };
} Elf64_Dyn;

typedef struct {
    uint64_t r_offset;
    uint32_t r_reloc_type;
    uint32_t r_symbol;
    uint64_t r_addend;
} Elf64_Rela;

typedef struct {
    uint64_t r_offset;
    uint32_t r_reloc_type;
    uint32_t r_symbol;
} Elf64_Rel;

typedef struct {
    uint32_t st_name;
    uint8_t st_info;
    uint8_t st_other;
    uint16_t st_shndx;
    uint64_t st_value;
    uint64_t st_size;
} Elf64_Sym;

enum {
    EI_MAG0,
    EI_MAG1,
    EI_MAG2,
    EI_MAG3,
    EI_CLASS,
    EI_DATA,
    EI_VERSION,
    EI_OSABI,
    EI_ABIVERSION,
    EI_NIDENT = 16
};

typedef struct {
    uint8_t e_ident[EI_NIDENT];
    uint16_t e_type;
    uint16_t e_machine;
    uint32_t e_version;
    uint64_t e_entry;
    uint64_t e_phoff;
    uint64_t e_shoff;
    uint32_t e_flags;
    uint16_t e_ehsize;
    uint16_t e_phentsize;
    uint16_t e_phnum;
    uint16_t e_shentsize;
    uint16_t e_shnum;
    uint16_t e_shstrndx;
} Elf64_Ehdr;

enum {
    PF_X = 0x1,
    PF_W = 0x2,
    PF_R = 0x4,
};

enum {
    PT_NULL,
    PT_LOAD,
    PT_DYNAMIC
};

typedef struct {
    uint32_t p_type;
    uint32_t p_flags;
    uint64_t p_offset;
    uint64_t p_vaddr;
    uint64_t p_paddr;
    uint64_t p_filesz;
    uint64_t p_memsz;
    uint64_t p_align;
} Elf64_Phdr;

#define STN_UNDEF 0
#define SHN_UNDEF 0

static_assert(sizeof(Elf64_Rela) == 0x18, "Elf64_Rela size should be 0x18");

enum {
    DT_NULL = 0,
    DT_NEEDED = 1,
    DT_PLTRELSZ = 2,
    DT_PLTGOT = 3,
    DT_HASH = 4,
    DT_STRTAB = 5,
    DT_SYMTAB = 6,
    DT_RELA = 7,
    DT_RELASZ = 8,
    DT_RELAENT = 9,
    DT_STRSZ = 10,
    DT_SYMENT = 11,
    // 12-15
    DT_SYMBOLIC = 16,
    DT_REL = 17,
    DT_RELSZ = 18,
    DT_RELENT = 19,
    DT_PLTREL = 20,
    // 21-22
    DT_JMPREL = 23,
    // 24
    DT_INIT_ARRAY = 25,
    DT_FINI_ARRAY = 26,
    DT_INIT_ARRAYSZ = 27,
    DT_FINI_ARRAYSZ = 28,
    // 29
    DT_FLAGS = 30,
    DT_GNU_HASH = 0x6ffffef5,
    DT_RELACOUNT = 0x6ffffff9,
};

result_t elf_dynamic_find_value(Elf64_Dyn *dynamic, int64_t tag, uint64_t *value);

result_t elf_dynamic_find_offset(Elf64_Dyn *dynamic, int64_t tag, void **value, void *base);

uint64_t elf_hash_string(const char *string);

#ifdef __cplusplus
}
#endif