feat: kernel is now elf

This commit is contained in:
karina
2026-04-26 09:32:07 +04:00
parent 1463402c6c
commit 6698c4ab3f
9 changed files with 137 additions and 42 deletions
+2 -2
View File
@@ -9,13 +9,13 @@ set(UEFI_COMPILE_OPTIONS
)
add_executable(BOOTAA64
Source/uefi/efi_entry.c
Source/modules/uefi/efi_entry.c
Source/main.c
)
target_compile_options(BOOTAA64 PRIVATE ${UEFI_COMPILE_OPTIONS})
target_include_directories(BOOTAA64 PRIVATE
${CMAKE_CURRENT_SOURCE_DIR}/Source
${CMAKE_CURRENT_SOURCE_DIR}/Source/uefi
${CMAKE_CURRENT_SOURCE_DIR}/Source/modules/uefi
)
target_link_options(BOOTAA64 PRIVATE
+78 -20
View File
@@ -1,10 +1,11 @@
#include "uefi/uefi.h"
#include "modules/uefi/uefi.h"
#include "modules/elf/elf.h"
#include "../../Common/bootinfo.h"
#define PAGE_SIZE 0x1000
#define WSTR(str) ((wchar_t*)L##str)
static wchar_t* kernel_path = WSTR("ksOSKernel.bin");
static wchar_t* kernel_path = WSTR("ksOSKernel.elf");
static efi_guid_t dtb_guid = {
0xb1b621d5, 0xf19c, 0x41a5, {0x83, 0x0b, 0xd9, 0x15, 0x2c, 0x69, 0xaa, 0xe0}
};
@@ -13,6 +14,14 @@ static void print(const wchar_t* msg) {
ST->ConOut->OutputString(ST->ConOut, (wchar_t*)msg);
}
void* memset(void* destination, int value, uint64_t count) {
uint8_t* ptr = (uint8_t*)destination;
while (count--) {
*ptr++ = (uint8_t)value;
}
return destination;
}
static efi_status_t die(void) {
while (1) {
__asm__ volatile("wfi");
@@ -83,33 +92,73 @@ static efi_status_t read_file_info(efi_file_handle_t* file, efi_file_info_t** fi
return file->GetInfo(file, &file_info_guid, &file_info_size, *file_info);
}
static efi_status_t load_kernel(efi_file_handle_t* root, efi_physical_address_t* kernel_addr, uint64_t* kernel_size) {
static efi_status_t load_kernel(efi_file_handle_t* root, efi_physical_address_t* kernel_addr, uint64_t* kernel_size, efi_file_handle_t** out_handle) {
efi_file_handle_t* kernel_file = NULL;
efi_file_info_t* kernel_info = NULL;
efi_status_t status = root->Open(root, &kernel_file, kernel_path, EFI_FILE_MODE_READ, 0);
if (EFI_ERROR(status)) {
return status;
}
if (EFI_ERROR(status)) return status;
efi_file_info_t* kernel_info = NULL;
status = read_file_info(kernel_file, &kernel_info);
if (EFI_ERROR(status)) {
return status;
}
if (EFI_ERROR(status)) return status;
*kernel_size = kernel_info->FileSize;
uintn_t bytes_to_read = (uintn_t)*kernel_size;
uintn_t kernel_pages = (*kernel_size + PAGE_SIZE - 1) / PAGE_SIZE;
*kernel_addr = 0;
status = gBS->AllocatePages(AllocateAnyPages, EfiLoaderData, kernel_pages, kernel_addr);
if (EFI_ERROR(status)) {
return status;
if (EFI_ERROR(status)) return status;
uintn_t bytes_to_read = (uintn_t)*kernel_size;
status = kernel_file->Read(kernel_file, &bytes_to_read, (void*)*kernel_addr);
if (EFI_ERROR(status)) return status;
*out_handle = kernel_file;
return EFI_SUCCESS;
}
static efi_status_t parse_elf_headers(efi_physical_address_t kernel_addr) {
Elf64_Ehdr* elf_header = (Elf64_Ehdr*)kernel_addr;
if (elf_header->e_ident[0] != 0x7f || elf_header->e_ident[1] != 'E' ||
elf_header->e_ident[2] != 'L' || elf_header->e_ident[3] != 'F') {
return fail(WSTR("Invalid ELF header\r\n"));
}
if (elf_header->e_machine != 0xB7) { // AArch64
return fail(WSTR("Invalid ELF machine\r\n"));
}
status = kernel_file->Read(kernel_file, &bytes_to_read, (void*)*kernel_addr);
if (EFI_ERROR(status) || bytes_to_read != (uintn_t)*kernel_size) {
return EFI_LOAD_ERROR;
return EFI_SUCCESS;
}
static efi_status_t load_elf_segments(efi_physical_address_t kernel_addr, efi_file_handle_t* kernel_file) {
Elf64_Ehdr* elf_header = (Elf64_Ehdr*)kernel_addr;
for (int i = 0; i < elf_header->e_phnum; i++) {
Elf64_Phdr* phdr = (Elf64_Phdr*)(kernel_addr + elf_header->e_phoff + i * elf_header->e_phentsize);
if (phdr->p_type != PT_LOAD) continue;
if (phdr->p_vaddr < 0x40000000) {
print(WSTR("Skipping low/weird segment\r\n"));
continue;
}
uintn_t pages = (phdr->p_memsz + 0xFFF) / 0x1000;
efi_physical_address_t segment_addr = phdr->p_vaddr;
efi_status_t status = gBS->AllocatePages(AllocateAddress, EfiLoaderData, pages, &segment_addr);
if (EFI_ERROR(status)) {
if (status == EFI_NOT_FOUND) print(WSTR(" (Range not in RAM) "));
if (status == EFI_OUT_OF_RESOURCES) print(WSTR(" (Occupied) "));
return fail(WSTR("Address conflict!\r\n"));
}
memset((void*)segment_addr, 0, phdr->p_memsz);
kernel_file->SetPosition(kernel_file, phdr->p_offset);
uintn_t size_to_read = phdr->p_filesz;
status = kernel_file->Read(kernel_file, &size_to_read, (void*)segment_addr);
if (EFI_ERROR(status) || size_to_read != phdr->p_filesz) {
return fail(WSTR("File read error\r\n"));
}
}
return EFI_SUCCESS;
@@ -175,11 +224,20 @@ efi_status_t bootloader_main(void) {
efi_physical_address_t kernel_addr = 0;
uint64_t kernel_size = 0;
status = load_kernel(root, &kernel_addr, &kernel_size);
efi_file_handle_t* kernel_file = NULL;
status = load_kernel(root, &kernel_addr, &kernel_size, &kernel_file);
if (EFI_ERROR(status)) {
return fail(WSTR("Failed to load ksOSKernel.bin\r\n"));
}
Elf64_Ehdr* elf_header = (Elf64_Ehdr*)kernel_addr;
status = parse_elf_headers(kernel_addr);
if (EFI_ERROR(status)) return status;
status = load_elf_segments(kernel_addr, kernel_file);
if (EFI_ERROR(status)) return status;
Bootinfo* boot_info = NULL;
status = gBS->AllocatePool(EfiLoaderData, sizeof(Bootinfo), (void**)&boot_info);
if (EFI_ERROR(status) || boot_info == NULL) {
@@ -203,7 +261,7 @@ efi_status_t bootloader_main(void) {
}
typedef void (*kernel_entry_t)(Bootinfo*);
kernel_entry_t kernel_main = (kernel_entry_t)kernel_addr;
kernel_entry_t kernel_main = (kernel_entry_t)elf_header->e_entry;
kernel_main(boot_info);
return EFI_SUCCESS;
+32
View File
@@ -0,0 +1,32 @@
#pragma once
#include "../../modules/uefi/uefi.h" // IWYU pragma: keep
typedef struct {
uint8_t e_ident[16];
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;
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 PT_LOAD 1
@@ -36,6 +36,8 @@ typedef uint16_t wchar_t;
#define EFI_LOAD_ERROR EFIERR(1)
#define EFI_UNSUPPORTED EFIERR(3)
#define EFI_BUFFER_TOO_SMALL EFIERR(5)
#define EFI_OUT_OF_RESOURCES EFIERR(9)
#define EFI_NOT_FOUND EFIERR(14)
#define EFI_ABORTED EFIERR(21)
#define EFI_OPEN_PROTOCOL_GET_PROTOCOL 0x00000002