mirror of
https://github.com/memtest86plus/memtest86plus.git
synced 2025-02-16 13:34:45 -06:00
b01c8e4388
We have a .setup section in the EFI image that contains the remainder of the Linux boot header and the real-mode setup code to support booting via an intermediate bootloader. This sits between the PE header and the .text section. We don't want the EFI loader to load this section, so simply increase the SizeOfHeader field in the PE header to cover it.
252 lines
6.5 KiB
ArmAsm
252 lines
6.5 KiB
ArmAsm
// SPDX-License-Identifier: GPL-2.0
|
|
//
|
|
// header.S supports booting directly from a UEFI BIOS or via an intermediate
|
|
// bootloader that supports the Linux boot protocol. When booted directly from
|
|
// the BIOS, it provides the MS-DOS & PE/COFF headers. When using an intermediate
|
|
// bootloader, it provides the first few bytes of the Linux boot header (at the
|
|
// end of the boot sector), with the remainder of the header being provided by
|
|
// setup.S.
|
|
//
|
|
// Copyright (C) 2020-2023 Martin Whitaker.
|
|
//
|
|
// Derived from Linux 5.6 arch/x86/boot/header.S:
|
|
//
|
|
// Copyright (C) 1991, 1992 Linus Torvalds
|
|
//
|
|
// Based on bootsect.S and setup.S
|
|
// modified by more people than can be counted
|
|
//
|
|
// Rewritten as a common file by H. Peter Anvin (Apr 2007)
|
|
|
|
#define __ASSEMBLY__
|
|
|
|
#include "boot.h"
|
|
#include "peimage.h"
|
|
|
|
# The EFI loader loads the header at ImageBase, so we have to locate the main program
|
|
# after that. This means we can't load the main program at HIGH_LOAD_ADDR. Pick a load
|
|
# address well away from HIGH_LOAD_ADDR, to avoid overlap when relocating the code.
|
|
|
|
#define IMAGE_BASE 0x200000
|
|
|
|
.section ".header", "ax", @progbits
|
|
.code16
|
|
|
|
.globl boot
|
|
boot:
|
|
# "MZ", the MS-DOS header signature.
|
|
.byte 0x4d
|
|
.byte 0x5a
|
|
|
|
# In case we are booted by a legacy BIOS, print an error message.
|
|
# Fortunately the MS-DOS header translates to harmless instructions.
|
|
|
|
ljmp $BOOT_SEG, $(error - boot)
|
|
error:
|
|
movw %cs, %ax
|
|
movw %ax, %ds
|
|
movw %ax, %es
|
|
movw %ax, %ss
|
|
xorw %sp, %sp
|
|
sti
|
|
cld
|
|
|
|
movw $error_msg, %si
|
|
0: lodsb
|
|
andb %al, %al
|
|
jz wait
|
|
movb $0xe, %ah
|
|
movw $7, %bx
|
|
int $0x10
|
|
jmp 0b
|
|
|
|
wait:
|
|
# Allow the user to press a key, then reboot.
|
|
xorw %ax, %ax
|
|
int $0x16
|
|
int $0x19
|
|
|
|
# int 0x19 should never return. In case it does, invoke the BIOS.
|
|
# reset code.
|
|
ljmp $0xf000,$0xfff0
|
|
|
|
# The PE header pointer.
|
|
.org 0x3c
|
|
.long pe_header
|
|
|
|
error_msg:
|
|
.ascii "This is a UEFI bootable image\r\n"
|
|
.ascii "\n"
|
|
.asciz "Press any key to reboot\r\n"
|
|
|
|
pe_header:
|
|
.ascii "PE"
|
|
.word 0
|
|
|
|
coff_header:
|
|
#ifdef __x86_64__
|
|
.word IMAGE_FILE_MACHINE_X64 # Machine (x86-64)
|
|
#else
|
|
.word IMAGE_FILE_MACHINE_I386 # Machine (i386)
|
|
#endif
|
|
.word 3 # NumberOfSections
|
|
.long 0 # TimeDateStamp
|
|
.long 0 # PointerToSymbolTable
|
|
.long 0 # NumberOfSymbols
|
|
.word section_table - optional_header # SizeOfOptionalHeader
|
|
#ifdef __x86_64__
|
|
.word IMAGE_FILE_DEBUG_STRIPPED \
|
|
| IMAGE_FILE_LOCAL_SYMS_STRIPPED \
|
|
| IMAGE_FILE_LINE_NUMS_STRIPPED \
|
|
| IMAGE_FILE_EXECUTABLE_IMAGE # Characteristics
|
|
#else
|
|
.word IMAGE_FILE_32BIT_MACHINE \
|
|
| IMAGE_FILE_DEBUG_STRIPPED \
|
|
| IMAGE_FILE_LOCAL_SYMS_STRIPPED \
|
|
| IMAGE_FILE_LINE_NUMS_STRIPPED \
|
|
| IMAGE_FILE_EXECUTABLE_IMAGE # Characteristics.
|
|
#endif
|
|
|
|
optional_header:
|
|
#ifdef __x86_64__
|
|
.word IMAGE_NT_OPTIONAL_HDR64_MAGIC # PE32+ format
|
|
#else
|
|
.word IMAGE_NT_OPTIONAL_HDR32_MAGIC # PE32 format
|
|
#endif
|
|
.byte 0x02 # MajorLinkerVersion
|
|
.byte 0x14 # MinorLinkerVersion
|
|
|
|
.long _virt_text_size # SizeOfCode
|
|
.long _virt_sbat_size # SizeOfInitializedData
|
|
.long 0 # SizeOfUninitializedData
|
|
|
|
.long _virt_text_start + 0x1e0 # AddressOfEntryPoint
|
|
|
|
.long _virt_text_start # BaseOfCode
|
|
#ifndef __x86_64__
|
|
.long _virt_sbat_start # BaseOfData
|
|
#endif
|
|
|
|
extra_header_fields:
|
|
#ifdef __x86_64__
|
|
.quad IMAGE_BASE # ImageBase
|
|
#else
|
|
.long IMAGE_BASE # ImageBase
|
|
#endif
|
|
.long 4096 # SectionAlignment
|
|
.long 512 # FileAlignment
|
|
.word 0 # MajorOperatingSystemVersion
|
|
.word 0 # MinorOperatingSystemVersion
|
|
.word 0 # MajorImageVersion
|
|
.word 0 # MinorImageVersion
|
|
.word 0 # MajorSubsystemVersion
|
|
.word 0 # MinorSubsystemVersion
|
|
.long 0 # Win32VersionValue
|
|
|
|
.long _virt_img_size # SizeOfImage
|
|
.long _file_head_size # SizeOfHeaders
|
|
.long 0 # CheckSum
|
|
.word 10 # Subsystem (EFI application)
|
|
.word 0 # DllCharacteristics
|
|
#ifdef __x86_64__
|
|
.quad 0 # SizeOfStackReserve
|
|
.quad 0 # SizeOfStackCommit
|
|
.quad 0 # SizeOfHeapReserve
|
|
.quad 0 # SizeOfHeapCommit
|
|
#else
|
|
.long 0 # SizeOfStackReserve
|
|
.long 0 # SizeOfStackCommit
|
|
.long 0 # SizeOfHeapReserve
|
|
.long 0 # SizeOfHeapCommit
|
|
#endif
|
|
.long 0 # LoaderFlags
|
|
.long IMAGE_DIRECTORY_ENTRY_DEBUG # NumberOfRvaAndSizes
|
|
|
|
.long 0 # DataDirectory.Export.VirtualAddress
|
|
.long 0 # DataDirectory.Export.Size
|
|
.long 0 # DataDirectory.Import.VirtualAddress
|
|
.long 0 # DataDirectory.Import.Size
|
|
.long 0 # DataDirectory.Resource.VirtualAddress
|
|
.long 0 # DataDirectory.Resource.Size
|
|
.long 0 # DataDirectory.Exception.VirtualAddress
|
|
.long 0 # DataDirectory.Exception.Size
|
|
.long 0 # DataDirectory.Certs.VirtualAddress
|
|
.long 0 # DataDirectory.Certs.Size
|
|
.long _virt_reloc_start # DataDirectory.BaseReloc.VirtualAddress
|
|
.long _real_reloc_size # DataDirectory.BaseReloc.Size
|
|
|
|
# Section table
|
|
section_table:
|
|
.ascii ".text"
|
|
.byte 0
|
|
.byte 0
|
|
.byte 0
|
|
.long _virt_text_size # VirtualSize
|
|
.long _virt_text_start # VirtualAddress
|
|
.long _file_text_size # SizeOfRawData
|
|
.long _file_text_start # PointerToRawData
|
|
.long 0 # PointerToRelocations
|
|
.long 0 # PointerToLineNumbers
|
|
.word 0 # NumberOfRelocations
|
|
.word 0 # NumberOfLineNumbers
|
|
.long IMAGE_SCN_MEM_READ \
|
|
| IMAGE_SCN_MEM_EXECUTE \
|
|
| IMAGE_SCN_CNT_CODE # Characteristics (section flags)
|
|
|
|
.ascii ".reloc"
|
|
.byte 0
|
|
.byte 0
|
|
.long _virt_reloc_size # VirtualSize
|
|
.long _virt_reloc_start # VirtualAddress
|
|
.long _file_reloc_size # SizeOfRawData
|
|
.long _file_reloc_start # PointerToRawData
|
|
.long 0 # PointerToRelocations
|
|
.long 0 # PointerToLineNumbers
|
|
.word 0 # NumberOfRelocations
|
|
.word 0 # NumberOfLineNumbers
|
|
.long IMAGE_SCN_MEM_READ \
|
|
| IMAGE_SCN_CNT_INITIALIZED_DATA # Characteristics (section flags)
|
|
|
|
.ascii ".sbat"
|
|
.byte 0
|
|
.byte 0
|
|
.byte 0
|
|
.long _virt_sbat_size # VirtualSize
|
|
.long _virt_sbat_start # VirtualAddress
|
|
.long _file_sbat_size # SizeOfRawData
|
|
.long _file_sbat_start # PointerToRawData
|
|
.long 0 # PointerToRelocations
|
|
.long 0 # PointerToLineNumbers
|
|
.word 0 # NumberOfRelocations
|
|
.word 0 # NumberOfLineNumbers
|
|
.long IMAGE_SCN_MEM_READ \
|
|
| IMAGE_SCN_CNT_INITIALIZED_DATA # Characteristics (section flags)
|
|
|
|
# Emulate the Linux boot header, to allow loading by intermediate boot loaders.
|
|
|
|
.org 497
|
|
setup_sects:
|
|
.byte SETUP_SECS
|
|
root_flags:
|
|
.word 0
|
|
sys_size:
|
|
.long _sys_size
|
|
ram_size:
|
|
.word 0
|
|
vid_mode:
|
|
.word 0
|
|
root_dev:
|
|
.word 0
|
|
boot_flag:
|
|
.word 0xAA55
|
|
|
|
.org 512
|
|
|
|
.section ".reloc"
|
|
.long 0 // Page RVA
|
|
.long 10 // Block Size (2*4+2)
|
|
.word (IMAGE_REL_BASED_ABSOLUTE << 12) + 0 // reloc 0 -> 0
|
|
|
|
.section ".sbat", "a", @progbits
|
|
.incbin "../boot/sbat.csv"
|