grub/grub-core/loader/i386/coreboot/chainloader.c
Vladimir Serbinenko aebe31c375 verifiers: File type for fine-grained signature-verification controlling
Let's provide file type info to the I/O layer. This way verifiers
framework and its users will be able to differentiate files and verify
only required ones.

This is preparatory patch.

Signed-off-by: Vladimir Serbinenko <phcoder@gmail.com>
Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com>
Reviewed-by: Ross Philipson <ross.philipson@oracle.com>
2020-09-21 13:29:05 -04:00

517 lines
13 KiB
C

/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2011 Free Software Foundation, Inc.
*
* GRUB 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 3 of the License, or
* (at your option) any later version.
*
* GRUB 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 GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
#include <grub/loader.h>
#include <grub/memory.h>
#include <grub/i386/memory.h>
#include <grub/file.h>
#include <grub/err.h>
#include <grub/dl.h>
#include <grub/mm.h>
#include <grub/elfload.h>
#include <grub/video.h>
#include <grub/relocator.h>
#include <grub/i386/relocator.h>
#include <grub/command.h>
#include <grub/i18n.h>
#include <grub/cbfs_core.h>
#include <grub/lib/LzmaDec.h>
#include <grub/efi/pe32.h>
#include <grub/i386/cpuid.h>
GRUB_MOD_LICENSE ("GPLv3+");
static grub_addr_t entry;
static struct grub_relocator *relocator = NULL;
static grub_err_t
grub_chain_boot (void)
{
struct grub_relocator32_state state;
grub_video_set_mode ("text", 0, 0);
state.eip = entry;
return grub_relocator32_boot (relocator, state, 0);
}
static grub_err_t
grub_chain_unload (void)
{
grub_relocator_unload (relocator);
relocator = NULL;
return GRUB_ERR_NONE;
}
static grub_err_t
load_elf (grub_file_t file, const char *filename)
{
grub_elf_t elf;
Elf32_Phdr *phdr;
grub_err_t err;
elf = grub_elf_file (file, filename);
if (!elf)
return grub_errno;
if (!grub_elf_is_elf32 (elf))
return grub_error (GRUB_ERR_BAD_OS, "only ELF32 can be coreboot payload");
entry = elf->ehdr.ehdr32.e_entry;
FOR_ELF32_PHDRS(elf, phdr)
{
grub_uint8_t *load_addr;
grub_relocator_chunk_t ch;
if (phdr->p_type != PT_LOAD)
continue;
err = grub_relocator_alloc_chunk_addr (relocator, &ch,
phdr->p_paddr, phdr->p_memsz);
if (err)
{
elf->file = 0;
grub_elf_close (elf);
return err;
}
load_addr = get_virtual_current_address (ch);
if (grub_file_seek (elf->file, phdr->p_offset) == (grub_off_t) -1)
{
elf->file = 0;
grub_elf_close (elf);
return grub_errno;
}
if (phdr->p_filesz)
{
grub_ssize_t read;
read = grub_file_read (elf->file, load_addr, phdr->p_filesz);
if (read != (grub_ssize_t) phdr->p_filesz)
{
if (!grub_errno)
grub_error (GRUB_ERR_FILE_READ_ERROR,
N_("premature end of file %s"),
filename);
elf->file = 0;
grub_elf_close (elf);
return grub_errno;
}
}
if (phdr->p_filesz < phdr->p_memsz)
grub_memset ((load_addr + phdr->p_filesz),
0, phdr->p_memsz - phdr->p_filesz);
}
elf->file = 0;
grub_elf_close (elf);
return GRUB_ERR_NONE;
}
static void *SzAlloc(void *p __attribute__ ((unused)), size_t size) { return grub_malloc (size); }
static void SzFree(void *p __attribute__ ((unused)), void *address) { grub_free (address); }
static ISzAlloc g_Alloc = { SzAlloc, SzFree };
static grub_err_t
load_segment (grub_file_t file, const char *filename,
void *load_addr, grub_uint32_t comp,
grub_size_t *size, grub_size_t max_size)
{
switch (comp)
{
case grub_cpu_to_be32_compile_time (CBFS_COMPRESS_NONE):
if (grub_file_read (file, load_addr, *size)
!= (grub_ssize_t) *size)
{
if (!grub_errno)
grub_error (GRUB_ERR_FILE_READ_ERROR,
N_("premature end of file %s"),
filename);
return grub_errno;
}
return GRUB_ERR_NONE;
case grub_cpu_to_be32_compile_time (CBFS_COMPRESS_LZMA):
{
grub_uint8_t *buf;
grub_size_t outsize, insize;
SRes res;
SizeT src_len, dst_len;
ELzmaStatus status;
if (*size < 13)
return grub_error (GRUB_ERR_BAD_OS, "invalid compressed chunk");
buf = grub_malloc (*size);
if (!buf)
return grub_errno;
if (grub_file_read (file, buf, *size)
!= (grub_ssize_t) *size)
{
if (!grub_errno)
grub_error (GRUB_ERR_FILE_READ_ERROR,
N_("premature end of file %s"),
filename);
grub_free (buf);
return grub_errno;
}
outsize = grub_get_unaligned64 (buf + 5);
if (outsize > max_size)
{
grub_free (buf);
return grub_error (GRUB_ERR_BAD_OS, "invalid compressed chunk");
}
insize = *size - 13;
src_len = insize;
dst_len = outsize;
res = LzmaDecode (load_addr, &dst_len, buf + 13, &src_len,
buf, 5, LZMA_FINISH_END, &status, &g_Alloc);
/* ELzmaFinishMode finishMode,
ELzmaStatus *status, ISzAlloc *alloc)*/
grub_free (buf);
grub_dprintf ("chain", "%x, %x, %x, %x\n",
insize, src_len, outsize, dst_len);
if (res != SZ_OK
|| src_len != insize || dst_len != outsize)
return grub_error (GRUB_ERR_BAD_OS, "decompression failure %d", res);
*size = outsize;
}
return GRUB_ERR_NONE;
default:
return grub_error (GRUB_ERR_BAD_OS, "unsupported compression %d",
grub_be_to_cpu32 (comp));
}
}
static grub_err_t
load_tianocore (grub_file_t file)
{
grub_uint16_t header_length;
grub_uint32_t section_head;
grub_uint8_t mz[2], pe[4];
struct grub_pe32_coff_header coff_head;
struct file_header
{
grub_uint8_t unused[18];
grub_uint8_t type;
grub_uint8_t unused2;
grub_uint8_t size[3];
grub_uint8_t unused3;
} file_head;
grub_relocator_chunk_t ch;
if (grub_file_seek (file, 48) == (grub_off_t) -1
|| grub_file_read (file, &header_length, sizeof (header_length))
!= sizeof (header_length)
|| grub_file_seek (file, header_length) == (grub_off_t) -1)
goto fail;
while (1)
{
grub_off_t off;
if (grub_file_read (file, &file_head, sizeof (file_head))
!= sizeof (file_head))
goto fail;
if (file_head.type != 0xf0)
break;
off = grub_get_unaligned32 (file_head.size) & 0xffffff;
if (off < sizeof (file_head))
goto fail;
if (grub_file_seek (file, grub_file_tell (file) + off
- sizeof (file_head)) == (grub_off_t) -1)
goto fail;
}
if (file_head.type != 0x03)
goto fail;
while (1)
{
if (grub_file_read (file, &section_head, sizeof (section_head))
!= sizeof (section_head))
goto fail;
if ((section_head >> 24) != 0x19)
break;
if ((section_head & 0xffffff) < sizeof (section_head))
goto fail;
if (grub_file_seek (file, grub_file_tell (file)
+ (section_head & 0xffffff)
- sizeof (section_head)) == (grub_off_t) -1)
goto fail;
}
if ((section_head >> 24) != 0x10)
goto fail;
grub_off_t exe_start = grub_file_tell (file);
if (grub_file_read (file, &mz, sizeof (mz)) != sizeof (mz))
goto fail;
if (mz[0] != 'M' || mz[1] != 'Z')
goto fail;
if (grub_file_seek (file, grub_file_tell (file) + 0x3a) == (grub_off_t) -1)
goto fail;
if (grub_file_read (file, &section_head, sizeof (section_head))
!= sizeof (section_head))
goto fail;
if (section_head < 0x40)
goto fail;
if (grub_file_seek (file, grub_file_tell (file)
+ section_head - 0x40) == (grub_off_t) -1)
goto fail;
if (grub_file_read (file, &pe, sizeof (pe))
!= sizeof (pe))
goto fail;
if (pe[0] != 'P' || pe[1] != 'E' || pe[2] != '\0' || pe[3] != '\0')
goto fail;
if (grub_file_read (file, &coff_head, sizeof (coff_head))
!= sizeof (coff_head))
goto fail;
grub_uint32_t loadaddr;
switch (coff_head.machine)
{
case GRUB_PE32_MACHINE_I386:
{
struct grub_pe32_optional_header oh;
if (grub_file_read (file, &oh, sizeof (oh))
!= sizeof (oh))
goto fail;
if (oh.magic != GRUB_PE32_PE32_MAGIC)
goto fail;
loadaddr = oh.image_base - exe_start;
entry = oh.image_base + oh.entry_addr;
break;
}
case GRUB_PE32_MACHINE_X86_64:
{
struct grub_pe64_optional_header oh;
if (! grub_cpuid_has_longmode)
{
grub_error (GRUB_ERR_BAD_OS, "your CPU does not implement AMD64 architecture");
goto fail;
}
if (grub_file_read (file, &oh, sizeof (oh))
!= sizeof (oh))
goto fail;
if (oh.magic != GRUB_PE32_PE64_MAGIC)
goto fail;
loadaddr = oh.image_base - exe_start;
entry = oh.image_base + oh.entry_addr;
break;
}
default:
goto fail;
}
if (grub_file_seek (file, 0) == (grub_off_t) -1)
goto fail;
grub_size_t fz = grub_file_size (file);
if (grub_relocator_alloc_chunk_addr (relocator, &ch,
loadaddr, fz))
goto fail;
if (grub_file_read (file, get_virtual_current_address (ch), fz)
!= (grub_ssize_t) fz)
goto fail;
return GRUB_ERR_NONE;
fail:
if (!grub_errno)
grub_error (GRUB_ERR_BAD_OS, "fv volume is invalid");
return grub_errno;
}
static grub_err_t
load_chewed (grub_file_t file, const char *filename)
{
grub_size_t i;
for (i = 0;; i++)
{
struct cbfs_payload_segment segment;
grub_err_t err;
if (grub_file_seek (file, sizeof (segment) * i) == (grub_off_t) -1
|| grub_file_read (file, &segment, sizeof (segment))
!= sizeof (segment))
{
if (!grub_errno)
return grub_error (GRUB_ERR_BAD_OS,
"payload is too short");
return grub_errno;
}
switch (segment.type)
{
case PAYLOAD_SEGMENT_PARAMS:
break;
case PAYLOAD_SEGMENT_ENTRY:
entry = grub_be_to_cpu64 (segment.load_addr);
return GRUB_ERR_NONE;
case PAYLOAD_SEGMENT_BSS:
segment.len = 0;
segment.offset = 0;
segment.len = 0;
/* Fallthrough. */
case PAYLOAD_SEGMENT_CODE:
case PAYLOAD_SEGMENT_DATA:
{
grub_uint32_t target = grub_be_to_cpu64 (segment.load_addr);
grub_uint32_t memsize = grub_be_to_cpu32 (segment.mem_len);
grub_uint32_t filesize = grub_be_to_cpu32 (segment.len);
grub_uint8_t *load_addr;
grub_relocator_chunk_t ch;
if (memsize < filesize)
memsize = filesize;
grub_dprintf ("chain", "%x+%x\n", target, memsize);
err = grub_relocator_alloc_chunk_addr (relocator, &ch,
target, memsize);
if (err)
return err;
load_addr = get_virtual_current_address (ch);
if (filesize)
{
if (grub_file_seek (file, grub_be_to_cpu32 (segment.offset))
== (grub_off_t) -1)
return grub_errno;
err = load_segment (file, filename, load_addr,
segment.compression, &filesize, memsize);
if (err)
return err;
}
if (filesize < memsize)
grub_memset ((load_addr + filesize),
0, memsize - filesize);
}
}
}
}
static grub_err_t
grub_cmd_chain (grub_command_t cmd __attribute__ ((unused)),
int argc, char *argv[])
{
grub_err_t err;
grub_file_t file;
grub_uint32_t head;
if (argc != 1)
return grub_error (GRUB_ERR_BAD_ARGUMENT, N_("filename expected"));
grub_loader_unset ();
file = grub_file_open (argv[0], GRUB_FILE_TYPE_COREBOOT_CHAINLOADER);
if (!file)
return grub_errno;
relocator = grub_relocator_new ();
if (!relocator)
{
grub_file_close (file);
return grub_errno;
}
if (grub_file_read (file, &head, sizeof (head)) != sizeof (head)
|| grub_file_seek (file, 0) == (grub_off_t) -1)
{
grub_file_close (file);
grub_relocator_unload (relocator);
relocator = 0;
if (!grub_errno)
return grub_error (GRUB_ERR_BAD_OS,
"payload is too short");
return grub_errno;
}
switch (head)
{
case ELFMAG0 | (ELFMAG1 << 8) | (ELFMAG2 << 16) | (ELFMAG3 << 24):
err = load_elf (file, argv[0]);
break;
case PAYLOAD_SEGMENT_CODE:
case PAYLOAD_SEGMENT_DATA:
case PAYLOAD_SEGMENT_PARAMS:
case PAYLOAD_SEGMENT_BSS:
case PAYLOAD_SEGMENT_ENTRY:
err = load_chewed (file, argv[0]);
break;
default:
if (grub_file_seek (file, 40) == (grub_off_t) -1
|| grub_file_read (file, &head, sizeof (head)) != sizeof (head)
|| grub_file_seek (file, 0) == (grub_off_t) -1
|| head != 0x4856465f)
err = grub_error (GRUB_ERR_BAD_OS, "unrecognised payload type");
else
err = load_tianocore (file);
break;
}
grub_file_close (file);
if (err)
{
grub_relocator_unload (relocator);
relocator = 0;
return err;
}
grub_loader_set (grub_chain_boot, grub_chain_unload, 0);
return GRUB_ERR_NONE;
}
static grub_command_t cmd_chain;
GRUB_MOD_INIT (chain)
{
cmd_chain = grub_register_command ("chainloader", grub_cmd_chain,
N_("FILE"),
/* TRANSLATORS: "payload" is a term used
by coreboot and must be translated in
sync with coreboot. If unsure,
let it untranslated. */
N_("Load another coreboot payload"));
}
GRUB_MOD_FINI (chain)
{
grub_unregister_command (cmd_chain);
grub_chain_unload ();
}