mirror of
https://github.com/RGBCube/serenity
synced 2025-07-25 16:17:45 +00:00
DynamicLoader+LibELF: Move self-relocation code into a separate file
This commit is contained in:
parent
3c616ae00f
commit
daeb371180
4 changed files with 85 additions and 45 deletions
|
@ -8,6 +8,7 @@
|
|||
#include <LibC/unistd.h>
|
||||
#include <LibELF/AuxiliaryVector.h>
|
||||
#include <LibELF/DynamicLinker.h>
|
||||
#include <LibELF/Relocation.h>
|
||||
|
||||
char* __static_environ[] = { nullptr }; // We don't get the environment without some libc workarounds..
|
||||
|
||||
|
@ -35,52 +36,8 @@ static void perform_self_relocations(auxv_t* auxvp)
|
|||
}
|
||||
}
|
||||
VERIFY(found_base_address);
|
||||
ElfW(Ehdr)* header = (ElfW(Ehdr)*)(base_address);
|
||||
ElfW(Phdr)* pheader = (ElfW(Phdr)*)(base_address + header->e_phoff);
|
||||
FlatPtr dynamic_section_addr = 0;
|
||||
for (size_t i = 0; i < (size_t)header->e_phnum; ++i, ++pheader) {
|
||||
if (pheader->p_type != PT_DYNAMIC)
|
||||
continue;
|
||||
dynamic_section_addr = pheader->p_vaddr + base_address;
|
||||
}
|
||||
if (!dynamic_section_addr)
|
||||
if (!ELF::perform_relative_relocations(base_address))
|
||||
exit(1);
|
||||
|
||||
FlatPtr relocation_section_addr = 0;
|
||||
size_t relocation_table_size = 0;
|
||||
size_t relocation_count = 0;
|
||||
bool use_addend = false;
|
||||
auto* dyns = reinterpret_cast<const ElfW(Dyn)*>(dynamic_section_addr);
|
||||
for (unsigned i = 0;; ++i) {
|
||||
auto& dyn = dyns[i];
|
||||
if (dyn.d_tag == DT_NULL)
|
||||
break;
|
||||
if (dyn.d_tag == DT_RELA)
|
||||
use_addend = true;
|
||||
if (dyn.d_tag == DT_REL || dyn.d_tag == DT_RELA)
|
||||
relocation_section_addr = base_address + dyn.d_un.d_ptr;
|
||||
else if (dyn.d_tag == DT_RELCOUNT || dyn.d_tag == DT_RELACOUNT)
|
||||
relocation_count = dyn.d_un.d_val;
|
||||
else if (dyn.d_tag == DT_RELSZ || dyn.d_tag == DT_RELASZ)
|
||||
relocation_table_size = dyn.d_un.d_val;
|
||||
}
|
||||
if (!relocation_section_addr || !relocation_table_size || !relocation_count)
|
||||
exit(1);
|
||||
|
||||
auto relocation_entry_size = relocation_table_size / relocation_count;
|
||||
for (unsigned i = 0; i < relocation_count; ++i) {
|
||||
size_t offset_in_section = i * relocation_entry_size;
|
||||
auto* relocation = (ElfW(Rela)*)(relocation_section_addr + offset_in_section);
|
||||
#if ARCH(I386)
|
||||
VERIFY(ELF32_R_TYPE(relocation->r_info) == R_386_RELATIVE);
|
||||
#else
|
||||
VERIFY(ELF64_R_TYPE(relocation->r_info) == R_X86_64_RELATIVE);
|
||||
#endif
|
||||
if (use_addend)
|
||||
*(FlatPtr*)(base_address + relocation->r_offset) = base_address + relocation->r_addend;
|
||||
else
|
||||
*(FlatPtr*)(base_address + relocation->r_offset) += base_address;
|
||||
}
|
||||
}
|
||||
|
||||
static void display_help()
|
||||
|
|
Loading…
Add table
Add a link
Reference in a new issue