452 lines
12 KiB
C
452 lines
12 KiB
C
/* multiboot.c - boot a multiboot OS image. */
|
|
/*
|
|
* GRUB -- GRand Unified Bootloader
|
|
* Copyright (C) 2003, 2004, 2005 Free Software Foundation, Inc.
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software
|
|
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
|
|
*/
|
|
|
|
/*
|
|
* FIXME: The following features from the Multiboot specification still
|
|
* need to be implemented:
|
|
* - VBE support
|
|
* - a.out support
|
|
* - boot device
|
|
* - symbol table
|
|
* - memory map
|
|
* - drives table
|
|
* - ROM configuration table
|
|
* - APM table
|
|
*/
|
|
|
|
#include <grub/loader.h>
|
|
#include <grub/machine/loader.h>
|
|
#include <grub/machine/multiboot.h>
|
|
#include <grub/machine/init.h>
|
|
#include <grub/elf.h>
|
|
#include <grub/file.h>
|
|
#include <grub/err.h>
|
|
#include <grub/rescue.h>
|
|
#include <grub/dl.h>
|
|
#include <grub/mm.h>
|
|
#include <grub/misc.h>
|
|
#include <grub/gzio.h>
|
|
|
|
static grub_dl_t my_mod;
|
|
static struct grub_multiboot_info *mbi;
|
|
static grub_addr_t entry;
|
|
|
|
static grub_err_t
|
|
grub_multiboot_boot (void)
|
|
{
|
|
grub_multiboot_real_boot (entry, mbi);
|
|
|
|
/* Not reached. */
|
|
return GRUB_ERR_NONE;
|
|
}
|
|
|
|
static grub_err_t
|
|
grub_multiboot_unload (void)
|
|
{
|
|
if (mbi)
|
|
{
|
|
unsigned int i;
|
|
for (i = 0; i < mbi->mods_count; i++)
|
|
{
|
|
grub_free ((void *)
|
|
((struct grub_mod_list *) mbi->mods_addr)[i].mod_start);
|
|
grub_free ((void *)
|
|
((struct grub_mod_list *) mbi->mods_addr)[i].cmdline);
|
|
}
|
|
grub_free ((void *) mbi->mods_addr);
|
|
grub_free ((void *) mbi->cmdline);
|
|
grub_free (mbi);
|
|
}
|
|
|
|
|
|
mbi = 0;
|
|
grub_dl_unref (my_mod);
|
|
|
|
return GRUB_ERR_NONE;
|
|
}
|
|
|
|
/* Check if BUFFER contains ELF32. */
|
|
static int
|
|
grub_multiboot_is_elf32 (void *buffer)
|
|
{
|
|
Elf32_Ehdr *ehdr = (Elf32_Ehdr *) buffer;
|
|
|
|
return ehdr->e_ident[EI_CLASS] == ELFCLASS32;
|
|
}
|
|
|
|
static grub_err_t
|
|
grub_multiboot_load_elf32 (grub_file_t file, void *buffer)
|
|
{
|
|
Elf32_Ehdr *ehdr = (Elf32_Ehdr *) buffer;
|
|
Elf32_Phdr *phdr;
|
|
int i;
|
|
|
|
if (ehdr->e_ident[EI_CLASS] != ELFCLASS32)
|
|
return grub_error (GRUB_ERR_UNKNOWN_OS, "invalid ELF class");
|
|
|
|
if (grub_dl_check_header (ehdr, sizeof(Elf32_Ehdr)))
|
|
return grub_error (GRUB_ERR_UNKNOWN_OS, "no valid ELF header found");
|
|
|
|
if (ehdr->e_type != ET_EXEC)
|
|
return grub_error (GRUB_ERR_UNKNOWN_OS, "invalid ELF file type");
|
|
|
|
/* FIXME: Should we support program headers at strange locations? */
|
|
if (ehdr->e_phoff + ehdr->e_phnum * ehdr->e_phentsize > GRUB_MB_SEARCH)
|
|
return grub_error (GRUB_ERR_BAD_OS, "program header at a too high offset");
|
|
|
|
entry = ehdr->e_entry;
|
|
|
|
/* Load every loadable segment in memory. */
|
|
for (i = 0; i < ehdr->e_phnum; i++)
|
|
{
|
|
phdr = (Elf32_Phdr *) ((char *) buffer + ehdr->e_phoff
|
|
+ i * ehdr->e_phentsize);
|
|
if (phdr->p_type == PT_LOAD)
|
|
{
|
|
/* The segment should fit in the area reserved for the OS. */
|
|
if ((phdr->p_paddr < grub_os_area_addr)
|
|
|| (phdr->p_paddr + phdr->p_memsz
|
|
> grub_os_area_addr + grub_os_area_size))
|
|
return grub_error (GRUB_ERR_BAD_OS,
|
|
"segment doesn't fit in memory reserved for the OS");
|
|
|
|
if (grub_file_seek (file, phdr->p_offset) == -1)
|
|
return grub_error (GRUB_ERR_BAD_OS,
|
|
"invalid offset in program header");
|
|
|
|
if (grub_file_read (file, (void *) phdr->p_paddr, phdr->p_filesz)
|
|
!= (grub_ssize_t) phdr->p_filesz)
|
|
return grub_error (GRUB_ERR_BAD_OS,
|
|
"couldn't read segment from file");
|
|
|
|
if (phdr->p_filesz < phdr->p_memsz)
|
|
grub_memset ((char *) phdr->p_paddr + phdr->p_filesz, 0,
|
|
phdr->p_memsz - phdr->p_filesz);
|
|
}
|
|
}
|
|
|
|
return grub_errno;
|
|
}
|
|
|
|
/* Check if BUFFER contains ELF64. */
|
|
static int
|
|
grub_multiboot_is_elf64 (void *buffer)
|
|
{
|
|
Elf64_Ehdr *ehdr = (Elf64_Ehdr *) buffer;
|
|
|
|
return ehdr->e_ident[EI_CLASS] == ELFCLASS64;
|
|
}
|
|
|
|
static grub_err_t
|
|
grub_multiboot_load_elf64 (grub_file_t file, void *buffer)
|
|
{
|
|
Elf64_Ehdr *ehdr = (Elf64_Ehdr *) buffer;
|
|
Elf64_Phdr *phdr;
|
|
int i;
|
|
|
|
if (ehdr->e_ident[EI_CLASS] != ELFCLASS64)
|
|
return grub_error (GRUB_ERR_UNKNOWN_OS, "invalid ELF class");
|
|
|
|
if (ehdr->e_ident[EI_MAG0] != ELFMAG0
|
|
|| ehdr->e_ident[EI_MAG1] != ELFMAG1
|
|
|| ehdr->e_ident[EI_MAG2] != ELFMAG2
|
|
|| ehdr->e_ident[EI_MAG3] != ELFMAG3
|
|
|| ehdr->e_version != EV_CURRENT
|
|
|| ehdr->e_ident[EI_DATA] != ELFDATA2LSB
|
|
|| ehdr->e_machine != EM_X86_64)
|
|
return grub_error(GRUB_ERR_UNKNOWN_OS, "no valid ELF header found");
|
|
|
|
if (ehdr->e_type != ET_EXEC)
|
|
return grub_error (GRUB_ERR_UNKNOWN_OS, "invalid ELF file type");
|
|
|
|
/* FIXME: Should we support program headers at strange locations? */
|
|
if (ehdr->e_phoff + ehdr->e_phnum * ehdr->e_phentsize > GRUB_MB_SEARCH)
|
|
return grub_error (GRUB_ERR_BAD_OS, "program header at a too high offset");
|
|
|
|
/* We still in 32-bit mode */
|
|
if (ehdr->e_entry > 0xffffffff)
|
|
return grub_error (GRUB_ERR_BAD_OS, "invalid entry point for ELF64");
|
|
|
|
entry = ehdr->e_entry;
|
|
|
|
/* Load every loadable segment in memory. */
|
|
for (i = 0; i < ehdr->e_phnum; i++)
|
|
{
|
|
phdr = (Elf64_Phdr *) ((char *) buffer + ehdr->e_phoff
|
|
+ i * ehdr->e_phentsize);
|
|
if (phdr->p_type == PT_LOAD)
|
|
{
|
|
/* The segment should fit in the area reserved for the OS. */
|
|
if ((phdr->p_paddr < (grub_uint64_t) grub_os_area_addr)
|
|
|| (phdr->p_paddr + phdr->p_memsz
|
|
> ((grub_uint64_t) grub_os_area_addr
|
|
+ (grub_uint64_t) grub_os_area_size)))
|
|
return grub_error (GRUB_ERR_BAD_OS,
|
|
"segment doesn't fit in memory reserved for the OS");
|
|
|
|
if (grub_file_seek (file, phdr->p_offset) == -1)
|
|
return grub_error (GRUB_ERR_BAD_OS,
|
|
"invalid offset in program header");
|
|
|
|
if (grub_file_read (file, (void *) ((grub_uint32_t) phdr->p_paddr),
|
|
phdr->p_filesz)
|
|
!= (grub_ssize_t) phdr->p_filesz)
|
|
return grub_error (GRUB_ERR_BAD_OS,
|
|
"couldn't read segment from file");
|
|
|
|
if (phdr->p_filesz < phdr->p_memsz)
|
|
grub_memset (((char *) ((grub_uint32_t) phdr->p_paddr)
|
|
+ phdr->p_filesz),
|
|
0,
|
|
phdr->p_memsz - phdr->p_filesz);
|
|
}
|
|
}
|
|
|
|
return grub_errno;
|
|
}
|
|
|
|
/* Load ELF32 or ELF64. */
|
|
static grub_err_t
|
|
grub_multiboot_load_elf (grub_file_t file, void *buffer)
|
|
{
|
|
if (grub_multiboot_is_elf32 (buffer))
|
|
return grub_multiboot_load_elf32 (file, buffer);
|
|
else if (grub_multiboot_is_elf64 (buffer))
|
|
return grub_multiboot_load_elf64 (file, buffer);
|
|
|
|
return grub_error (GRUB_ERR_UNKNOWN_OS, "unknown ELF class");
|
|
}
|
|
|
|
void
|
|
grub_rescue_cmd_multiboot (int argc, char *argv[])
|
|
{
|
|
grub_file_t file = 0;
|
|
char buffer[GRUB_MB_SEARCH], *cmdline = 0, *p;
|
|
struct grub_multiboot_header *header;
|
|
grub_ssize_t len;
|
|
int i;
|
|
|
|
grub_dl_ref (my_mod);
|
|
|
|
grub_loader_unset ();
|
|
|
|
if (argc == 0)
|
|
{
|
|
grub_error (GRUB_ERR_BAD_ARGUMENT, "No kernel specified");
|
|
goto fail;
|
|
}
|
|
|
|
file = grub_gzfile_open (argv[0], 1);
|
|
if (! file)
|
|
{
|
|
grub_error (GRUB_ERR_BAD_ARGUMENT, "Couldn't open file");
|
|
goto fail;
|
|
}
|
|
|
|
len = grub_file_read (file, buffer, GRUB_MB_SEARCH);
|
|
if (len < 32)
|
|
{
|
|
grub_error (GRUB_ERR_BAD_OS, "File too small");
|
|
goto fail;
|
|
}
|
|
|
|
/* Look for the multiboot header in the buffer. The header should
|
|
be at least 12 bytes and aligned on a 4-byte boundary. */
|
|
for (header = (struct grub_multiboot_header *) buffer;
|
|
((char *) header <= buffer + len - 12) || (header = 0);
|
|
header = (struct grub_multiboot_header *) ((char *) header + 4))
|
|
{
|
|
if (header->magic == GRUB_MB_MAGIC
|
|
&& !(header->magic + header->flags + header->checksum))
|
|
break;
|
|
}
|
|
|
|
if (header == 0)
|
|
{
|
|
grub_error (GRUB_ERR_BAD_ARGUMENT, "No multiboot header found");
|
|
goto fail;
|
|
}
|
|
|
|
if (header->flags & GRUB_MB_UNSUPPORTED)
|
|
{
|
|
grub_error (GRUB_ERR_UNKNOWN_OS,
|
|
"Unsupported flag: 0x%x", header->flags);
|
|
goto fail;
|
|
}
|
|
|
|
if (grub_multiboot_load_elf (file, buffer) != GRUB_ERR_NONE)
|
|
goto fail;
|
|
|
|
mbi = grub_malloc (sizeof (struct grub_multiboot_info));
|
|
if (! mbi)
|
|
goto fail;
|
|
|
|
mbi->flags = GRUB_MB_INFO_MEMORY;
|
|
|
|
/* Convert from bytes to kilobytes. */
|
|
mbi->mem_lower = grub_lower_mem / 1024;
|
|
mbi->mem_upper = grub_upper_mem / 1024;
|
|
|
|
for (i = 0, len = 0; i < argc; i++)
|
|
len += grub_strlen (argv[i]) + 1;
|
|
|
|
cmdline = p = grub_malloc (len);
|
|
if (! cmdline)
|
|
goto fail;
|
|
|
|
for (i = 0; i < argc; i++)
|
|
{
|
|
p = grub_stpcpy (p, argv[i]);
|
|
*(p++) = ' ';
|
|
}
|
|
|
|
/* Remove the space after the last word. */
|
|
*(--p) = '\0';
|
|
|
|
mbi->flags |= GRUB_MB_INFO_CMDLINE;
|
|
mbi->cmdline = (grub_uint32_t) cmdline;
|
|
|
|
mbi->flags |= GRUB_MB_INFO_BOOT_LOADER_NAME;
|
|
mbi->boot_loader_name = (grub_uint32_t) grub_strdup (PACKAGE_STRING);
|
|
|
|
grub_loader_set (grub_multiboot_boot, grub_multiboot_unload);
|
|
|
|
fail:
|
|
if (file)
|
|
grub_file_close (file);
|
|
|
|
if (grub_errno != GRUB_ERR_NONE)
|
|
{
|
|
grub_free (cmdline);
|
|
grub_free (mbi);
|
|
grub_dl_unref (my_mod);
|
|
}
|
|
}
|
|
|
|
|
|
void
|
|
grub_rescue_cmd_module (int argc, char *argv[])
|
|
{
|
|
grub_file_t file = 0;
|
|
grub_ssize_t size, len = 0;
|
|
char *module = 0, *cmdline = 0, *p;
|
|
int i;
|
|
|
|
if (argc == 0)
|
|
{
|
|
grub_error (GRUB_ERR_BAD_ARGUMENT, "No module specified");
|
|
goto fail;
|
|
}
|
|
|
|
if (!mbi)
|
|
{
|
|
grub_error (GRUB_ERR_BAD_ARGUMENT,
|
|
"You need to load the multiboot kernel first");
|
|
goto fail;
|
|
}
|
|
|
|
file = grub_gzfile_open (argv[0], 1);
|
|
if (! file)
|
|
goto fail;
|
|
|
|
size = grub_file_size (file);
|
|
module = grub_memalign (GRUB_MB_MOD_ALIGN, size);
|
|
if (! module)
|
|
goto fail;
|
|
|
|
if (grub_file_read (file, module, size) != size)
|
|
{
|
|
grub_error (GRUB_ERR_FILE_READ_ERROR, "Couldn't read file");
|
|
goto fail;
|
|
}
|
|
|
|
for (i = 0; i < argc; i++)
|
|
len += grub_strlen (argv[i]) + 1;
|
|
|
|
cmdline = p = grub_malloc (len);
|
|
if (! cmdline)
|
|
goto fail;
|
|
|
|
for (i = 0; i < argc; i++)
|
|
{
|
|
p = grub_stpcpy (p, argv[i]);
|
|
*(p++) = ' ';
|
|
}
|
|
|
|
/* Remove the space after the last word. */
|
|
*(--p) = '\0';
|
|
|
|
if (mbi->flags & GRUB_MB_INFO_MODS)
|
|
{
|
|
struct grub_mod_list *modlist = (struct grub_mod_list *) mbi->mods_addr;
|
|
|
|
modlist = grub_realloc (modlist, (mbi->mods_count + 1)
|
|
* sizeof (struct grub_mod_list));
|
|
if (! modlist)
|
|
goto fail;
|
|
mbi->mods_addr = (grub_uint32_t) modlist;
|
|
modlist += mbi->mods_count;
|
|
modlist->mod_start = (grub_uint32_t) module;
|
|
modlist->mod_end = (grub_uint32_t) module + size;
|
|
modlist->cmdline = (grub_uint32_t) cmdline;
|
|
modlist->pad = 0;
|
|
mbi->mods_count++;
|
|
}
|
|
else
|
|
{
|
|
struct grub_mod_list *modlist = grub_malloc (sizeof (struct grub_mod_list));
|
|
if (! modlist)
|
|
goto fail;
|
|
modlist->mod_start = (grub_uint32_t) module;
|
|
modlist->mod_end = (grub_uint32_t) module + size;
|
|
modlist->cmdline = (grub_uint32_t) cmdline;
|
|
modlist->pad = 0;
|
|
mbi->mods_count = 1;
|
|
mbi->mods_addr = (grub_uint32_t) modlist;
|
|
mbi->flags |= GRUB_MB_INFO_MODS;
|
|
}
|
|
|
|
fail:
|
|
if (file)
|
|
grub_file_close (file);
|
|
|
|
if (grub_errno != GRUB_ERR_NONE)
|
|
{
|
|
grub_free (module);
|
|
grub_free (cmdline);
|
|
}
|
|
}
|
|
|
|
|
|
GRUB_MOD_INIT
|
|
{
|
|
grub_rescue_register_command ("multiboot", grub_rescue_cmd_multiboot,
|
|
"load a multiboot kernel");
|
|
grub_rescue_register_command ("module", grub_rescue_cmd_module,
|
|
"load a multiboot module");
|
|
my_mod = mod;
|
|
}
|
|
|
|
GRUB_MOD_FINI
|
|
{
|
|
grub_rescue_unregister_command ("multiboot");
|
|
grub_rescue_unregister_command ("module");
|
|
}
|