grub/grub-core/lib/cmdline.c
Matthew Garrett 2d410729e9 Measure the kernel commandline
Measure the kernel commandline to ensure that it hasn't been modified
2016-01-05 14:35:17 -08:00

112 lines
2.2 KiB
C

/* cmdline.c - linux command line handling */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2010 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/lib/cmdline.h>
#include <grub/misc.h>
#include <grub/tpm.h>
static unsigned int check_arg (char *c, int *has_space)
{
int space = 0;
unsigned int size = 0;
while (*c)
{
if (*c == '\\' || *c == '\'' || *c == '"')
size++;
else if (*c == ' ')
space = 1;
size++;
c++;
}
if (space)
size += 2;
if (has_space)
*has_space = space;
return size;
}
unsigned int grub_loader_cmdline_size (int argc, char *argv[])
{
int i;
unsigned int size = 0;
for (i = 0; i < argc; i++)
{
size += check_arg (argv[i], 0);
size++; /* Separator space or NULL. */
}
if (size == 0)
size = 1;
return size;
}
int grub_create_loader_cmdline (int argc, char *argv[], char *buf,
grub_size_t size)
{
int i, space;
unsigned int arg_size;
char *c, *orig = buf;
for (i = 0; i < argc; i++)
{
c = argv[i];
arg_size = check_arg(argv[i], &space);
arg_size++; /* Separator space or NULL. */
if (size < arg_size)
break;
size -= arg_size;
if (space)
*buf++ = '"';
while (*c)
{
if (*c == '\\' || *c == '\'' || *c == '"')
*buf++ = '\\';
*buf++ = *c;
c++;
}
if (space)
*buf++ = '"';
*buf++ = ' ';
}
/* Replace last space with null. */
if (i)
buf--;
*buf = 0;
grub_tpm_measure ((void *)orig, grub_strlen (orig), GRUB_CMDLINE_PCR,
"Kernel Commandline");
return i;
}