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#pragma once
#include <LibELF/ELFImage.h>
#include <LibELF/exec_elf.h>
#include <dlfcn.h>
#include <mman.h>
#include <AK/OwnPtr.h>
#include <AK/RefCounted.h>
#include <AK/String.h>
#define ALIGN_ROUND_UP(x, align) ((((size_t)(x)) + align - 1) & (~(align - 1)))
class ELFDynamicObject : public RefCounted<ELFDynamicObject> {
public:
static NonnullRefPtr<ELFDynamicObject> construct(const char* filename, int fd, size_t file_size);
~ELFDynamicObject();
bool is_valid() const { return m_valid; }
// FIXME: How can we resolve all of the symbols without having the original elf image for our process?
// RTLD_LAZY only at first probably... though variables ('objects') need resolved at load time every time
bool load(unsigned flags);
// Intended for use by dlsym or other internal methods
void* symbol_for_name(const char*);
void dump();
private:
class ProgramHeaderRegion {
public:
ProgramHeaderRegion(const Elf32_Phdr& header)
: m_program_header(header)
{
}
VirtualAddress load_address() const { return m_load_address; }
VirtualAddress base_address() const { return m_image_base_address; }
void set_load_address(VirtualAddress addr) { m_load_address = addr; }
void set_base_address(VirtualAddress addr) { m_image_base_address = addr; }
// Information from ELF Program header
u32 type() const { return m_program_header.p_type; }
u32 flags() const { return m_program_header.p_flags; }
u32 offset() const { return m_program_header.p_offset; }
VirtualAddress desired_load_address() const { return VirtualAddress(m_program_header.p_vaddr); }
u32 size_in_memory() const { return m_program_header.p_memsz; }
u32 size_in_image() const { return m_program_header.p_filesz; }
u32 alignment() const { return m_program_header.p_align; }
u32 mmap_prot() const;
bool is_readable() const { return flags() & PF_R; }
bool is_writable() const { return flags() & PF_W; }
bool is_executable() const { return flags() & PF_X; }
bool is_tls_template() const { return type() == PT_TLS; }
bool is_load() const { return type() == PT_LOAD; }
bool is_dynamic() const { return type() == PT_DYNAMIC; }
u32 required_load_size() { return ALIGN_ROUND_UP(m_program_header.p_memsz, m_program_header.p_align); }
private:
Elf32_Phdr m_program_header; // Explictly a copy of the PHDR in the image
VirtualAddress m_load_address { 0 };
VirtualAddress m_image_base_address { 0 };
};
explicit ELFDynamicObject(const char* filename, int fd, size_t file_size);
String m_filename;
size_t m_file_size { 0 };
int m_image_fd { -1 };
void* m_file_mapping { nullptr };
bool m_valid { false };
OwnPtr<ELFImage> m_image;
void parse_dynamic_section();
void do_relocations();
static void patch_plt_entry(u32 got_offset, void* dso_got_tag);
Vector<ProgramHeaderRegion> m_program_header_regions;
ProgramHeaderRegion* m_text_region { nullptr };
ProgramHeaderRegion* m_data_region { nullptr };
ProgramHeaderRegion* m_tls_region { nullptr };
// Begin Section information collected from DT_* entries
uintptr_t m_init_offset { 0 };
uintptr_t m_fini_offset { 0 };
uintptr_t m_init_array_offset { 0 };
size_t m_init_array_size { 0 };
uintptr_t m_hash_table_offset { 0 };
uintptr_t m_string_table_offset { 0 };
uintptr_t m_symbol_table_offset { 0 };
size_t m_size_of_string_table { 0 };
size_t m_size_of_symbol_table_entry { 0 };
Elf32_Sword m_procedure_linkage_table_relocation_type { -1 };
uintptr_t m_plt_relocation_offset_location { 0 }; // offset of PLT relocations, at end of relocations
size_t m_size_of_plt_relocation_entry_list { 0 };
uintptr_t m_procedure_linkage_table_offset { 0 };
// NOTE: We'll only ever either RELA or REL entries, not both (thank god)
size_t m_number_of_relocations { 0 };
size_t m_size_of_relocation_entry { 0 };
size_t m_size_of_relocation_table { 0 };
uintptr_t m_relocation_table_offset { 0 };
// DT_FLAGS
bool m_should_process_origin = false;
bool m_requires_symbolic_symbol_resolution = false;
// Text relocations meaning: we need to edit the .text section which is normally mapped PROT_READ
bool m_has_text_relocations = false;
bool m_must_bind_now = false; // FIXME: control with an environment var as well?
bool m_has_static_thread_local_storage = false;
// End Section information from DT_* entries
};
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