grub/grub-core/loader/arm/linux.c
Vladimir Serbinenko 0f20a51812 verifiers: Add possibility to verify kernel and modules command lines
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 13:46:34 -04:00

509 lines
13 KiB
C

/* linux.c - boot Linux */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2013 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/dl.h>
#include <grub/fdt.h>
#include <grub/file.h>
#include <grub/loader.h>
#include <grub/mm.h>
#include <grub/misc.h>
#include <grub/command.h>
#include <grub/cache.h>
#include <grub/cpu/linux.h>
#include <grub/lib/cmdline.h>
#include <grub/linux.h>
#include <grub/verify.h>
GRUB_MOD_LICENSE ("GPLv3+");
static grub_dl_t my_mod;
static grub_addr_t initrd_start;
static grub_addr_t initrd_end;
static grub_addr_t linux_addr;
static grub_size_t linux_size;
static char *linux_args;
static grub_uint32_t machine_type;
static const void *current_fdt;
typedef void (*kernel_entry_t) (int, unsigned long, void *);
#define LINUX_PHYS_OFFSET (0x00008000)
#define LINUX_INITRD_PHYS_OFFSET (LINUX_PHYS_OFFSET + 0x02000000)
#define LINUX_FDT_PHYS_OFFSET (LINUX_INITRD_PHYS_OFFSET - 0x10000)
static grub_size_t
get_atag_size (const grub_uint32_t *atag)
{
const grub_uint32_t *atag0 = atag;
while (atag[0] && atag[1])
atag += atag[0];
return atag - atag0;
}
/*
* linux_prepare_fdt():
* Prepares a loaded FDT for being passed to Linux.
* Merges in command line parameters and sets up initrd addresses.
*/
static grub_err_t
linux_prepare_atag (void *target_atag)
{
const grub_uint32_t *atag_orig = (const grub_uint32_t *) current_fdt;
grub_uint32_t *tmp_atag, *to;
const grub_uint32_t *from;
grub_size_t tmp_size;
grub_size_t arg_size = grub_strlen (linux_args);
char *cmdline_orig = NULL;
grub_size_t cmdline_orig_len = 0;
/* some place for cmdline, initrd and terminator. */
tmp_size = get_atag_size (atag_orig) + 20 + (arg_size) / 4;
tmp_atag = grub_malloc (tmp_size * sizeof (grub_uint32_t));
if (!tmp_atag)
return grub_errno;
for (from = atag_orig, to = tmp_atag; from[0] && from[1];
from += from[0])
switch (from[1])
{
case 0x54410004:
case 0x54410005:
case 0x54420005:
break;
case 0x54410009:
if (*(char *) (from + 2))
{
cmdline_orig = (char *) (from + 2);
cmdline_orig_len = grub_strlen (cmdline_orig) + 1;
}
break;
default:
grub_memcpy (to, from, sizeof (grub_uint32_t) * from[0]);
to += from[0];
break;
}
grub_dprintf ("linux", "linux inherited args: '%s'\n",
cmdline_orig ? : "");
grub_dprintf ("linux", "linux_args: '%s'\n", linux_args);
/* Generate and set command line */
to[0] = 3 + (arg_size + cmdline_orig_len) / 4;
to[1] = 0x54410009;
if (cmdline_orig)
{
grub_memcpy ((char *) to + 8, cmdline_orig, cmdline_orig_len - 1);
*((char *) to + 8 + cmdline_orig_len - 1) = ' ';
}
grub_memcpy ((char *) to + 8 + cmdline_orig_len, linux_args, arg_size);
grub_memset ((char *) to + 8 + cmdline_orig_len + arg_size, 0,
4 - ((arg_size + cmdline_orig_len) & 3));
to += to[0];
if (initrd_start && initrd_end)
{
/*
* We're using physical addresses, so even if we have LPAE, we're
* restricted to a 32-bit address space.
*/
grub_dprintf ("loader", "Initrd @ 0x%08x-0x%08x\n",
initrd_start, initrd_end);
to[0] = 4;
to[1] = 0x54420005;
to[2] = initrd_start;
to[3] = initrd_end - initrd_start;
to += 4;
}
to[0] = 0;
to[1] = 0;
to += 2;
/* Copy updated FDT to its launch location */
grub_memcpy (target_atag, tmp_atag, sizeof (grub_uint32_t) * (to - tmp_atag));
grub_free (tmp_atag);
grub_dprintf ("loader", "ATAG updated for Linux boot\n");
return GRUB_ERR_NONE;
}
/*
* linux_prepare_fdt():
* Prepares a loaded FDT for being passed to Linux.
* Merges in command line parameters and sets up initrd addresses.
*/
static grub_err_t
linux_prepare_fdt (void *target_fdt)
{
int node;
int retval;
int tmp_size;
void *tmp_fdt;
tmp_size = grub_fdt_get_totalsize (current_fdt) + 0x100 + grub_strlen (linux_args);
tmp_fdt = grub_malloc (tmp_size);
if (!tmp_fdt)
return grub_errno;
grub_memcpy (tmp_fdt, current_fdt, grub_fdt_get_totalsize (current_fdt));
grub_fdt_set_totalsize (tmp_fdt, tmp_size);
/* Find or create '/chosen' node */
node = grub_fdt_find_subnode (tmp_fdt, 0, "chosen");
if (node < 0)
{
grub_dprintf ("linux", "No 'chosen' node in FDT - creating.\n");
node = grub_fdt_add_subnode (tmp_fdt, 0, "chosen");
if (node < 0)
goto failure;
}
grub_dprintf ("linux", "linux_args: '%s'\n", linux_args);
/* Generate and set command line */
retval = grub_fdt_set_prop (tmp_fdt, node, "bootargs", linux_args,
grub_strlen (linux_args) + 1);
if (retval)
goto failure;
if (initrd_start && initrd_end)
{
/*
* We're using physical addresses, so even if we have LPAE, we're
* restricted to a 32-bit address space.
*/
grub_dprintf ("loader", "Initrd @ 0x%08x-0x%08x\n",
initrd_start, initrd_end);
retval = grub_fdt_set_prop32 (tmp_fdt, node, "linux,initrd-start",
initrd_start);
if (retval)
goto failure;
retval = grub_fdt_set_prop32 (tmp_fdt, node, "linux,initrd-end",
initrd_end);
if (retval)
goto failure;
}
/* Copy updated FDT to its launch location */
grub_memcpy (target_fdt, tmp_fdt, tmp_size);
grub_free (tmp_fdt);
grub_dprintf ("loader", "FDT updated for Linux boot\n");
return GRUB_ERR_NONE;
failure:
grub_free (tmp_fdt);
return grub_error (GRUB_ERR_BAD_ARGUMENT, "unable to prepare FDT");
}
static grub_err_t
linux_boot (void)
{
kernel_entry_t linuxmain;
int fdt_valid, atag_valid;
void *target_fdt = 0;
fdt_valid = (current_fdt && grub_fdt_check_header_nosize (current_fdt) == 0);
atag_valid = ((((const grub_uint16_t *) current_fdt)[3] & ~3) == 0x5440
&& *((const grub_uint32_t *) current_fdt));
grub_dprintf ("loader", "atag: %p, %x, %x, %s, %s\n",
current_fdt,
((const grub_uint16_t *) current_fdt)[3],
*((const grub_uint32_t *) current_fdt),
(const char *) current_fdt,
(const char *) current_fdt + 1);
if (!fdt_valid && machine_type == GRUB_ARM_MACHINE_TYPE_FDT)
return grub_error (GRUB_ERR_FILE_NOT_FOUND,
N_("device tree must be supplied (see `devicetree' command)"));
grub_arch_sync_caches ((void *) linux_addr, linux_size);
grub_dprintf ("loader", "Kernel at: 0x%x\n", linux_addr);
if (fdt_valid || atag_valid)
{
#ifdef GRUB_MACHINE_EFI
grub_size_t size;
if (fdt_valid)
size = grub_fdt_get_totalsize (current_fdt);
else
size = 4 * get_atag_size (current_fdt);
size += grub_strlen (linux_args) + 256;
target_fdt = grub_efi_allocate_loader_memory (LINUX_FDT_PHYS_OFFSET, size);
if (!target_fdt)
return grub_error (GRUB_ERR_OUT_OF_MEMORY, N_("out of memory"));
#else
target_fdt = (void *) LINUX_FDT_ADDRESS;
#endif
}
if (fdt_valid)
{
grub_err_t err;
err = linux_prepare_fdt (target_fdt);
if (err)
return err;
grub_dprintf ("loader", "FDT @ %p\n", target_fdt);
}
else if (atag_valid)
{
grub_err_t err;
err = linux_prepare_atag (target_fdt);
if (err)
return err;
grub_dprintf ("loader", "ATAG @ %p\n", target_fdt);
}
grub_dprintf ("loader", "Jumping to Linux...\n");
/* Boot the kernel.
* Arguments to kernel:
* r0 - 0
* r1 - machine type
* r2 - address of DTB
*/
linuxmain = (kernel_entry_t) linux_addr;
grub_arm_disable_caches_mmu ();
linuxmain (0, machine_type, target_fdt);
return grub_error (GRUB_ERR_BAD_OS, "Linux call returned");
}
/*
* Only support zImage, so no relocations necessary
*/
static grub_err_t
linux_load (const char *filename, grub_file_t file)
{
struct linux_arm_kernel_header *lh;
int size;
size = grub_file_size (file);
linux_addr = LINUX_ADDRESS;
grub_dprintf ("loader", "Loading Linux to 0x%08x\n",
(grub_addr_t) linux_addr);
if (grub_file_read (file, (void *) linux_addr, size) != size)
{
if (!grub_errno)
grub_error (GRUB_ERR_BAD_OS, N_("premature end of file %s"),
filename);
return grub_errno;
}
lh = (void *) linux_addr;
if ((grub_size_t) size > sizeof (*lh) &&
lh->magic == GRUB_LINUX_ARM_MAGIC_SIGNATURE)
;
else if (size > 0x8000 && *(grub_uint32_t *) (linux_addr) == 0xea000006
&& machine_type == GRUB_ARM_MACHINE_TYPE_RASPBERRY_PI)
grub_memmove ((void *) linux_addr, (void *) (linux_addr + 0x8000),
size - 0x8000);
else
return grub_error (GRUB_ERR_BAD_FILE_TYPE, N_("invalid zImage"));
linux_size = size;
return GRUB_ERR_NONE;
}
static grub_err_t
linux_unload (void)
{
grub_dl_unref (my_mod);
grub_free (linux_args);
linux_args = NULL;
initrd_start = initrd_end = 0;
return GRUB_ERR_NONE;
}
static grub_err_t
grub_cmd_linux (grub_command_t cmd __attribute__ ((unused)),
int argc, char *argv[])
{
int size;
grub_err_t err;
grub_file_t file;
grub_dl_ref (my_mod);
if (argc == 0)
return grub_error (GRUB_ERR_BAD_ARGUMENT, N_("filename expected"));
file = grub_file_open (argv[0]);
if (!file)
goto fail;
err = linux_load (argv[0], file);
grub_file_close (file);
if (err)
goto fail;
grub_loader_set (linux_boot, linux_unload, 0);
size = grub_loader_cmdline_size (argc, argv);
linux_args = grub_malloc (size + sizeof (LINUX_IMAGE));
if (!linux_args)
{
grub_loader_unset();
goto fail;
}
/* Create kernel command line. */
grub_memcpy (linux_args, LINUX_IMAGE, sizeof (LINUX_IMAGE));
err = grub_create_loader_cmdline (argc, argv,
linux_args + sizeof (LINUX_IMAGE) - 1, size,
GRUB_VERIFY_KERNEL_CMDLINE);
if (err)
goto fail;
return GRUB_ERR_NONE;
fail:
grub_dl_unref (my_mod);
return grub_errno;
}
static grub_err_t
grub_cmd_initrd (grub_command_t cmd __attribute__ ((unused)),
int argc, char *argv[])
{
grub_file_t file;
grub_size_t size = 0;
struct grub_linux_initrd_context initrd_ctx = { 0, 0, 0 };
if (argc == 0)
return grub_error (GRUB_ERR_BAD_ARGUMENT, N_("filename expected"));
file = grub_file_open (argv[0]);
if (!file)
return grub_errno;
if (grub_initrd_init (argc, argv, &initrd_ctx))
goto fail;
size = grub_get_initrd_size (&initrd_ctx);
initrd_start = LINUX_INITRD_ADDRESS;
grub_dprintf ("loader", "Loading initrd to 0x%08x\n",
(grub_addr_t) initrd_start);
if (grub_initrd_load (&initrd_ctx, argv, (void *) initrd_start))
goto fail;
initrd_end = initrd_start + size;
return GRUB_ERR_NONE;
fail:
grub_file_close (file);
return grub_errno;
}
static grub_err_t
load_dtb (grub_file_t dtb, int size)
{
void *new_fdt = grub_zalloc (size);
if (!new_fdt)
return grub_errno;
grub_dprintf ("loader", "Loading device tree to %p\n",
new_fdt);
if ((grub_file_read (dtb, new_fdt, size) != size)
|| (grub_fdt_check_header (new_fdt, size) != 0))
{
grub_free (new_fdt);
return grub_error (GRUB_ERR_BAD_OS, N_("invalid device tree"));
}
grub_fdt_set_totalsize (new_fdt, size);
current_fdt = new_fdt;
/*
* We've successfully loaded an FDT, so any machine type passed
* from firmware is now obsolete.
*/
machine_type = GRUB_ARM_MACHINE_TYPE_FDT;
return GRUB_ERR_NONE;
}
static grub_err_t
grub_cmd_devicetree (grub_command_t cmd __attribute__ ((unused)),
int argc, char *argv[])
{
grub_file_t dtb;
int size;
if (argc != 1)
return grub_error (GRUB_ERR_BAD_ARGUMENT, N_("filename expected"));
dtb = grub_file_open (argv[0]);
if (!dtb)
return grub_errno;
size = grub_file_size (dtb);
if (size == 0)
grub_error (GRUB_ERR_BAD_OS, "empty file");
else
load_dtb (dtb, size);
grub_file_close (dtb);
return grub_errno;
}
static grub_command_t cmd_linux, cmd_initrd, cmd_devicetree;
GRUB_MOD_INIT (linux)
{
cmd_linux = grub_register_command ("linux", grub_cmd_linux,
0, N_("Load Linux."));
cmd_initrd = grub_register_command ("initrd", grub_cmd_initrd,
0, N_("Load initrd."));
cmd_devicetree = grub_register_command ("devicetree", grub_cmd_devicetree,
/* TRANSLATORS: DTB stands for device tree blob. */
0, N_("Load DTB file."));
my_mod = mod;
current_fdt = (const void *) grub_arm_firmware_get_boot_data ();
machine_type = grub_arm_firmware_get_machine_type ();
}
GRUB_MOD_FINI (linux)
{
grub_unregister_command (cmd_linux);
grub_unregister_command (cmd_initrd);
grub_unregister_command (cmd_devicetree);
}