First step of moving bootloader to C++
This commit is contained in:
Justin C. Miller
255
src/boot/loader.cpp
Normal file
255
src/boot/loader.cpp
Normal file
@@ -0,0 +1,255 @@
|
||||
#include "elf.h"
|
||||
#include "guids.h"
|
||||
#include "loader.h"
|
||||
#include "memory.h"
|
||||
#include "utility.h"
|
||||
|
||||
#define PAGE_SIZE 0x1000
|
||||
|
||||
static wchar_t kernel_name[] = KERNEL_FILENAME;
|
||||
static wchar_t initrd_name[] = INITRD_FILENAME;
|
||||
|
||||
EFI_STATUS
|
||||
loader_alloc_pages(
|
||||
EFI_BOOT_SERVICES *bootsvc,
|
||||
EFI_MEMORY_TYPE mem_type,
|
||||
size_t *length,
|
||||
void **pages)
|
||||
{
|
||||
EFI_STATUS status;
|
||||
|
||||
size_t page_count = ((*length - 1) / PAGE_SIZE) + 1;
|
||||
EFI_PHYSICAL_ADDRESS addr = (EFI_PHYSICAL_ADDRESS)*pages;
|
||||
|
||||
status = bootsvc->AllocatePages(AllocateAddress, mem_type, page_count, &addr);
|
||||
if (status == EFI_NOT_FOUND || status == EFI_OUT_OF_RESOURCES) {
|
||||
// couldn't get the address we wanted, try loading the kernel anywhere
|
||||
status =
|
||||
bootsvc->AllocatePages(AllocateAnyPages, mem_type, page_count, &addr);
|
||||
}
|
||||
CHECK_EFI_STATUS_OR_RETURN(status,
|
||||
L"Allocating %d kernel pages type %x",
|
||||
page_count, mem_type);
|
||||
|
||||
*length = page_count * PAGE_SIZE;
|
||||
*pages = (void *)addr;
|
||||
|
||||
return EFI_SUCCESS;
|
||||
}
|
||||
|
||||
EFI_STATUS
|
||||
loader_load_initrd(
|
||||
EFI_BOOT_SERVICES *bootsvc,
|
||||
EFI_FILE_PROTOCOL *root,
|
||||
struct loader_data *data)
|
||||
{
|
||||
EFI_STATUS status;
|
||||
|
||||
EFI_FILE_PROTOCOL *file = NULL;
|
||||
status = root->Open(root, &file, (wchar_t *)initrd_name, EFI_FILE_MODE_READ,
|
||||
EFI_FILE_READ_ONLY | EFI_FILE_HIDDEN | EFI_FILE_SYSTEM);
|
||||
|
||||
if (status == EFI_NOT_FOUND)
|
||||
return status;
|
||||
|
||||
CHECK_EFI_STATUS_OR_RETURN(status, L"Opening file %s", initrd_name);
|
||||
|
||||
char info[sizeof(EFI_FILE_INFO) + 100];
|
||||
size_t info_length = sizeof(info);
|
||||
|
||||
status = file->GetInfo(file, &guid_file_info, &info_length, info);
|
||||
CHECK_EFI_STATUS_OR_RETURN(status, L"Getting file info");
|
||||
|
||||
data->initrd_length = ((EFI_FILE_INFO *)info)->FileSize;
|
||||
|
||||
status = loader_alloc_pages(
|
||||
bootsvc,
|
||||
INITRD_MEMTYPE,
|
||||
&data->initrd_length,
|
||||
&data->initrd);
|
||||
CHECK_EFI_STATUS_OR_RETURN(status, L"Allocating pages");
|
||||
|
||||
status = file->Read(file, &data->initrd_length, data->initrd);
|
||||
CHECK_EFI_STATUS_OR_RETURN(status, L"Reading file");
|
||||
|
||||
status = file->Close(file);
|
||||
CHECK_EFI_STATUS_OR_RETURN(status, L"Closing file handle");
|
||||
|
||||
return EFI_SUCCESS;
|
||||
}
|
||||
|
||||
|
||||
EFI_STATUS
|
||||
loader_load_elf(
|
||||
EFI_BOOT_SERVICES *bootsvc,
|
||||
EFI_FILE_PROTOCOL *root,
|
||||
struct loader_data *data)
|
||||
{
|
||||
EFI_STATUS status;
|
||||
|
||||
con_debug(L"Opening kernel file %s\r\n", (wchar_t *)kernel_name);
|
||||
|
||||
EFI_FILE_PROTOCOL *file = NULL;
|
||||
status = root->Open(root, &file, (wchar_t *)kernel_name, EFI_FILE_MODE_READ,
|
||||
EFI_FILE_READ_ONLY | EFI_FILE_HIDDEN | EFI_FILE_SYSTEM);
|
||||
|
||||
if (status == EFI_NOT_FOUND)
|
||||
return status;
|
||||
|
||||
uint64_t length = 0;
|
||||
data->kernel = 0;
|
||||
data->kernel_entry = 0;
|
||||
data->kernel_length = 0;
|
||||
|
||||
CHECK_EFI_STATUS_OR_RETURN(status, L"Opening file %s", kernel_name);
|
||||
|
||||
struct elf_header header;
|
||||
|
||||
length = sizeof(struct elf_header);
|
||||
status = file->Read(file, &length, &header);
|
||||
CHECK_EFI_STATUS_OR_RETURN(status, L"Reading ELF header");
|
||||
|
||||
con_debug(L"Read %u bytes of ELF header\r\n", length);
|
||||
|
||||
if (length < sizeof(struct elf_header))
|
||||
CHECK_EFI_STATUS_OR_RETURN(EFI_LOAD_ERROR, L"Incomplete read of ELF header");
|
||||
|
||||
static const char expected[] = {0x7f, 'E', 'L', 'F'};
|
||||
for (int i = 0; i < sizeof(expected); ++i) {
|
||||
if (header.ident.magic[i] != expected[i])
|
||||
CHECK_EFI_STATUS_OR_RETURN(EFI_LOAD_ERROR, L"Bad ELF magic number");
|
||||
}
|
||||
|
||||
if (header.ident.word_size != ELF_WORDSIZE)
|
||||
CHECK_EFI_STATUS_OR_RETURN(EFI_LOAD_ERROR, L"ELF load error: 32 bit ELF not supported");
|
||||
|
||||
if (header.ph_entsize != sizeof(struct elf_program_header))
|
||||
CHECK_EFI_STATUS_OR_RETURN(EFI_LOAD_ERROR, L"ELF load error: program header size mismatch");
|
||||
|
||||
if (header.ident.version != ELF_VERSION ||
|
||||
header.version != ELF_VERSION)
|
||||
CHECK_EFI_STATUS_OR_RETURN(EFI_LOAD_ERROR, L"ELF load error: wrong ELF version");
|
||||
|
||||
if (header.ident.endianness != 1 ||
|
||||
header.ident.os_abi != 0 ||
|
||||
header.machine != 0x3e)
|
||||
CHECK_EFI_STATUS_OR_RETURN(EFI_LOAD_ERROR, L"ELF load error: wrong machine architecture");
|
||||
|
||||
con_debug(L"ELF is valid, entrypoint %lu\r\n", header.entrypoint);
|
||||
|
||||
data->kernel_entry = (void *)header.entrypoint;
|
||||
|
||||
struct elf_program_header prog_header;
|
||||
for (int i = 0; i < header.ph_num; ++i) {
|
||||
con_debug(L"Reading ELF program header %d\r\n", i);
|
||||
|
||||
status = file->SetPosition(file, header.ph_offset + i * header.ph_entsize);
|
||||
CHECK_EFI_STATUS_OR_RETURN(status, L"Setting ELF file position");
|
||||
|
||||
length = header.ph_entsize;
|
||||
status = file->Read(file, &length, &prog_header);
|
||||
CHECK_EFI_STATUS_OR_RETURN(status, L"Reading ELF program header");
|
||||
|
||||
if (prog_header.type != ELF_PT_LOAD) continue;
|
||||
|
||||
length = prog_header.mem_size;
|
||||
void *addr = (void *)(prog_header.vaddr - KERNEL_VIRT_ADDRESS);
|
||||
status = loader_alloc_pages(bootsvc, KERNEL_MEMTYPE, &length, &addr);
|
||||
CHECK_EFI_STATUS_OR_RETURN(status, L"Allocating kernel pages");
|
||||
|
||||
if (data->kernel == 0)
|
||||
data->kernel = addr;
|
||||
data->kernel_length = (uint64_t)addr + length - (uint64_t)data->kernel;
|
||||
}
|
||||
|
||||
struct elf_section_header sec_header;
|
||||
for (int i = 0; i < header.sh_num; ++i) {
|
||||
con_debug(L"Reading ELF section header %d ", i);
|
||||
|
||||
status = file->SetPosition(file, header.sh_offset + i * header.sh_entsize);
|
||||
CHECK_EFI_STATUS_OR_RETURN(status, L"Setting ELF file position");
|
||||
|
||||
length = header.sh_entsize;
|
||||
status = file->Read(file, &length, &sec_header);
|
||||
CHECK_EFI_STATUS_OR_RETURN(status, L"Reading ELF section header");
|
||||
|
||||
if ((sec_header.flags & ELF_SHF_ALLOC) == 0) {
|
||||
con_debug(L"SHF_ALLOC section\r\n");
|
||||
continue;
|
||||
}
|
||||
|
||||
void *addr = (void *)(sec_header.addr - KERNEL_VIRT_ADDRESS);
|
||||
|
||||
if (sec_header.type == ELF_ST_PROGBITS) {
|
||||
con_debug(L"PROGBITS section\r\n");
|
||||
status = file->SetPosition(file, sec_header.offset);
|
||||
CHECK_EFI_STATUS_OR_RETURN(status, L"Setting ELF file position");
|
||||
|
||||
length = sec_header.size;
|
||||
status = file->Read(file, &length, addr);
|
||||
CHECK_EFI_STATUS_OR_RETURN(status, L"Reading file");
|
||||
} else if (sec_header.type == ELF_ST_NOBITS) {
|
||||
con_debug(L"NOBITS section\r\n");
|
||||
bootsvc->SetMem(addr, sec_header.size, 0);
|
||||
} else {
|
||||
con_debug(L"other section\r\n");
|
||||
}
|
||||
}
|
||||
|
||||
status = file->Close(file);
|
||||
CHECK_EFI_STATUS_OR_RETURN(status, L"Closing file handle");
|
||||
|
||||
return EFI_SUCCESS;
|
||||
}
|
||||
|
||||
|
||||
EFI_STATUS
|
||||
loader_load_kernel(
|
||||
EFI_BOOT_SERVICES *bootsvc,
|
||||
struct loader_data *data)
|
||||
{
|
||||
if (data == NULL)
|
||||
CHECK_EFI_STATUS_OR_RETURN(EFI_INVALID_PARAMETER, L"NULL loader_data");
|
||||
|
||||
EFI_STATUS status;
|
||||
EFI_HANDLE *handles = NULL;
|
||||
size_t handleCount = 0;
|
||||
|
||||
status = bootsvc->LocateHandleBuffer(ByProtocol, &guid_simple_filesystem, NULL, &handleCount, &handles);
|
||||
CHECK_EFI_STATUS_OR_RETURN(status, L"LocateHandleBuffer");
|
||||
|
||||
for (unsigned i = 0; i < handleCount; ++i) {
|
||||
EFI_SIMPLE_FILE_SYSTEM_PROTOCOL *fileSystem = NULL;
|
||||
|
||||
status = bootsvc->HandleProtocol(handles[i], &guid_simple_filesystem, (void **)&fileSystem);
|
||||
CHECK_EFI_STATUS_OR_RETURN(status, L"HandleProtocol");
|
||||
|
||||
EFI_FILE_PROTOCOL *root = NULL;
|
||||
status = fileSystem->OpenVolume(fileSystem, &root);
|
||||
CHECK_EFI_STATUS_OR_RETURN(status, L"OpenVolume");
|
||||
|
||||
status = loader_load_elf(bootsvc, root, data);
|
||||
if (status == EFI_NOT_FOUND)
|
||||
continue;
|
||||
|
||||
CHECK_EFI_STATUS_OR_RETURN(status, L"loader_load_elf: %s", kernel_name);
|
||||
|
||||
data->initrd = (void *)((uint64_t)data->kernel + data->kernel_length);
|
||||
status = loader_load_initrd(bootsvc, root, data);
|
||||
|
||||
CHECK_EFI_STATUS_OR_RETURN(status, L"loader_load_file: %s", initrd_name);
|
||||
|
||||
data->data = (void *)((uint64_t)data->initrd + data->initrd_length);
|
||||
data->data_length += PAGE_SIZE; // extra page for map growth
|
||||
status = loader_alloc_pages(
|
||||
bootsvc,
|
||||
KERNEL_DATA_MEMTYPE,
|
||||
&data->data_length,
|
||||
&data->data);
|
||||
CHECK_EFI_STATUS_OR_RETURN(status, L"loader_alloc_pages: kernel data");
|
||||
|
||||
return EFI_SUCCESS;
|
||||
}
|
||||
|
||||
return EFI_NOT_FOUND;
|
||||
}
|
||||
Reference in New Issue
Block a user