u-boot/common/cmd_nvedit.c
Wolfgang Denk 54841ab50c Make sure that argv[] argument pointers are not modified.
The hush shell dynamically allocates (and re-allocates) memory for the
argument strings in the "char *argv[]" argument vector passed to
commands.  Any code that modifies these pointers will cause serious
corruption of the malloc data structures and crash U-Boot, so make
sure the compiler can check that no such modifications are being done
by changing the code into "char * const argv[]".

This modification is the result of debugging a strange crash caused
after adding a new command, which used the following argument
processing code which has been working perfectly fine in all Unix
systems since version 6 - but not so in U-Boot:

int main (int argc, char **argv)
{
	while (--argc > 0 && **++argv == '-') {
/* ====> */	while (*++*argv) {
			switch (**argv) {
			case 'd':
				debug++;
				break;
			...
			default:
				usage ();
			}
		}
	}
	...
}

The line marked "====>" will corrupt the malloc data structures and
usually cause U-Boot to crash when the next command gets executed by
the shell.  With the modification, the compiler will prevent this with
an
	error: increment of read-only location '*argv'

N.B.: The code above can be trivially rewritten like this:

	while (--argc > 0 && **++argv == '-') {
		char *arg = *argv;
		while (*++arg) {
			switch (*arg) {
			...

Signed-off-by: Wolfgang Denk <wd@denx.de>
Acked-by: Mike Frysinger <vapier@gentoo.org>
2010-07-04 23:55:42 +02:00

670 lines
15 KiB
C

/*
* (C) Copyright 2000-2002
* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
*
* (C) Copyright 2001 Sysgo Real-Time Solutions, GmbH <www.elinos.com>
* Andreas Heppel <aheppel@sysgo.de>
* See file CREDITS for list of people who contributed to this
* project.
*
* 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., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
/**************************************************************************
*
* Support for persistent environment data
*
* The "environment" is stored as a list of '\0' terminated
* "name=value" strings. The end of the list is marked by a double
* '\0'. New entries are always added at the end. Deleting an entry
* shifts the remaining entries to the front. Replacing an entry is a
* combination of deleting the old value and adding the new one.
*
* The environment is preceeded by a 32 bit CRC over the data part.
*
**************************************************************************
*/
#include <common.h>
#include <command.h>
#include <environment.h>
#if defined(CONFIG_CMD_EDITENV)
#include <malloc.h>
#endif
#include <watchdog.h>
#include <serial.h>
#include <linux/stddef.h>
#include <asm/byteorder.h>
#if defined(CONFIG_CMD_NET)
#include <net.h>
#endif
DECLARE_GLOBAL_DATA_PTR;
#if !defined(CONFIG_ENV_IS_IN_EEPROM) && \
!defined(CONFIG_ENV_IS_IN_FLASH) && \
!defined(CONFIG_ENV_IS_IN_DATAFLASH) && \
!defined(CONFIG_ENV_IS_IN_MG_DISK) && \
!defined(CONFIG_ENV_IS_IN_NAND) && \
!defined(CONFIG_ENV_IS_IN_NVRAM) && \
!defined(CONFIG_ENV_IS_IN_ONENAND) && \
!defined(CONFIG_ENV_IS_IN_SPI_FLASH) && \
!defined(CONFIG_ENV_IS_NOWHERE)
# error Define one of CONFIG_ENV_IS_IN_{EEPROM|FLASH|DATAFLASH|ONENAND|\
SPI_FLASH|MG_DISK|NVRAM|NOWHERE}
#endif
#define XMK_STR(x) #x
#define MK_STR(x) XMK_STR(x)
/************************************************************************
************************************************************************/
/*
* Table with supported baudrates (defined in config_xyz.h)
*/
static const unsigned long baudrate_table[] = CONFIG_SYS_BAUDRATE_TABLE;
#define N_BAUDRATES (sizeof(baudrate_table) / sizeof(baudrate_table[0]))
/*
* This variable is incremented on each do_setenv (), so it can
* be used via get_env_id() as an indication, if the environment
* has changed or not. So it is possible to reread an environment
* variable only if the environment was changed ... done so for
* example in NetInitLoop()
*/
static int env_id = 1;
int get_env_id (void)
{
return env_id;
}
/************************************************************************
* Command interface: print one or all environment variables
*/
/*
* state 0: finish printing this string and return (matched!)
* state 1: no matching to be done; print everything
* state 2: continue searching for matched name
*/
static int printenv(char *name, int state)
{
int i, j;
char c, buf[17];
i = 0;
buf[16] = '\0';
while (state && env_get_char(i) != '\0') {
if (state == 2 && envmatch((uchar *)name, i) >= 0)
state = 0;
j = 0;
do {
buf[j++] = c = env_get_char(i++);
if (j == sizeof(buf) - 1) {
if (state <= 1)
puts(buf);
j = 0;
}
} while (c != '\0');
if (state <= 1) {
if (j)
puts(buf);
putc('\n');
}
if (ctrlc())
return -1;
}
if (state == 0)
i = 0;
return i;
}
int do_printenv (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
int i;
int rcode = 0;
if (argc == 1) {
/* print all env vars */
rcode = printenv(NULL, 1);
if (rcode < 0)
return 1;
printf("\nEnvironment size: %d/%ld bytes\n",
rcode, (ulong)ENV_SIZE);
return 0;
}
/* print selected env vars */
for (i = 1; i < argc; ++i) {
char *name = argv[i];
if (printenv(name, 2)) {
printf("## Error: \"%s\" not defined\n", name);
++rcode;
}
}
return rcode;
}
/************************************************************************
* Set a new environment variable,
* or replace or delete an existing one.
*
* This function will ONLY work with a in-RAM copy of the environment
*/
int _do_setenv (int flag, int argc, char * const argv[])
{
int i, len, oldval;
int console = -1;
uchar *env, *nxt = NULL;
char *name;
bd_t *bd = gd->bd;
uchar *env_data = env_get_addr(0);
if (!env_data) /* need copy in RAM */
return 1;
name = argv[1];
if (strchr(name, '=')) {
printf ("## Error: illegal character '=' in variable name \"%s\"\n", name);
return 1;
}
env_id++;
/*
* search if variable with this name already exists
*/
oldval = -1;
for (env=env_data; *env; env=nxt+1) {
for (nxt=env; *nxt; ++nxt)
;
if ((oldval = envmatch((uchar *)name, env-env_data)) >= 0)
break;
}
/* Check for console redirection */
if (strcmp(name,"stdin") == 0) {
console = stdin;
} else if (strcmp(name,"stdout") == 0) {
console = stdout;
} else if (strcmp(name,"stderr") == 0) {
console = stderr;
}
if (console != -1) {
if (argc < 3) { /* Cannot delete it! */
printf("Can't delete \"%s\"\n", name);
return 1;
}
#ifdef CONFIG_CONSOLE_MUX
i = iomux_doenv(console, argv[2]);
if (i)
return i;
#else
/* Try assigning specified device */
if (console_assign (console, argv[2]) < 0)
return 1;
#ifdef CONFIG_SERIAL_MULTI
if (serial_assign (argv[2]) < 0)
return 1;
#endif
#endif /* CONFIG_CONSOLE_MUX */
}
/*
* Delete any existing definition
*/
if (oldval >= 0) {
#ifndef CONFIG_ENV_OVERWRITE
/*
* Ethernet Address and serial# can be set only once,
* ver is readonly.
*/
if (
#ifdef CONFIG_HAS_UID
/* Allow serial# forced overwrite with 0xdeaf4add flag */
((strcmp (name, "serial#") == 0) && (flag != 0xdeaf4add)) ||
#else
(strcmp (name, "serial#") == 0) ||
#endif
((strcmp (name, "ethaddr") == 0)
#if defined(CONFIG_OVERWRITE_ETHADDR_ONCE) && defined(CONFIG_ETHADDR)
&& (strcmp ((char *)env_get_addr(oldval),MK_STR(CONFIG_ETHADDR)) != 0)
#endif /* CONFIG_OVERWRITE_ETHADDR_ONCE && CONFIG_ETHADDR */
) ) {
printf ("Can't overwrite \"%s\"\n", name);
return 1;
}
#endif
/*
* Switch to new baudrate if new baudrate is supported
*/
if (strcmp(argv[1],"baudrate") == 0) {
int baudrate = simple_strtoul(argv[2], NULL, 10);
int i;
for (i=0; i<N_BAUDRATES; ++i) {
if (baudrate == baudrate_table[i])
break;
}
if (i == N_BAUDRATES) {
printf ("## Baudrate %d bps not supported\n",
baudrate);
return 1;
}
printf ("## Switch baudrate to %d bps and press ENTER ...\n",
baudrate);
udelay(50000);
gd->baudrate = baudrate;
#if defined(CONFIG_PPC) || defined(CONFIG_MCF52x2)
gd->bd->bi_baudrate = baudrate;
#endif
serial_setbrg ();
udelay(50000);
for (;;) {
if (getc() == '\r')
break;
}
}
if (*++nxt == '\0') {
if (env > env_data) {
env--;
} else {
*env = '\0';
}
} else {
for (;;) {
*env = *nxt++;
if ((*env == '\0') && (*nxt == '\0'))
break;
++env;
}
}
*++env = '\0';
}
/* Delete only ? */
if ((argc < 3) || argv[2] == NULL) {
env_crc_update ();
return 0;
}
/*
* Append new definition at the end
*/
for (env=env_data; *env || *(env+1); ++env)
;
if (env > env_data)
++env;
/*
* Overflow when:
* "name" + "=" + "val" +"\0\0" > ENV_SIZE - (env-env_data)
*/
len = strlen(name) + 2;
/* add '=' for first arg, ' ' for all others */
for (i=2; i<argc; ++i) {
len += strlen(argv[i]) + 1;
}
if (len > (&env_data[ENV_SIZE]-env)) {
printf ("## Error: environment overflow, \"%s\" deleted\n", name);
return 1;
}
while ((*env = *name++) != '\0')
env++;
for (i=2; i<argc; ++i) {
char *val = argv[i];
*env = (i==2) ? '=' : ' ';
while ((*++env = *val++) != '\0')
;
}
/* end is marked with double '\0' */
*++env = '\0';
/* Update CRC */
env_crc_update ();
/*
* Some variables should be updated when the corresponding
* entry in the enviornment is changed
*/
if (strcmp(argv[1],"ethaddr") == 0)
return 0;
if (strcmp(argv[1],"ipaddr") == 0) {
char *s = argv[2]; /* always use only one arg */
char *e;
unsigned long addr;
bd->bi_ip_addr = 0;
for (addr=0, i=0; i<4; ++i) {
ulong val = s ? simple_strtoul(s, &e, 10) : 0;
addr <<= 8;
addr |= (val & 0xFF);
if (s) s = (*e) ? e+1 : e;
}
bd->bi_ip_addr = htonl(addr);
return 0;
}
if (strcmp(argv[1],"loadaddr") == 0) {
load_addr = simple_strtoul(argv[2], NULL, 16);
return 0;
}
#if defined(CONFIG_CMD_NET)
if (strcmp(argv[1],"bootfile") == 0) {
copy_filename (BootFile, argv[2], sizeof(BootFile));
return 0;
}
#endif
return 0;
}
int setenv (char *varname, char *varvalue)
{
char * const argv[4] = { "setenv", varname, varvalue, NULL };
if ((varvalue == NULL) || (varvalue[0] == '\0'))
return _do_setenv (0, 2, argv);
else
return _do_setenv (0, 3, argv);
}
#ifdef CONFIG_HAS_UID
void forceenv (char *varname, char *varvalue)
{
char * const argv[4] = { "forceenv", varname, varvalue, NULL };
_do_setenv (0xdeaf4add, 3, argv);
}
#endif
int do_setenv (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
if (argc < 2) {
cmd_usage(cmdtp);
return 1;
}
return _do_setenv (flag, argc, argv);
}
/************************************************************************
* Prompt for environment variable
*/
#if defined(CONFIG_CMD_ASKENV)
int do_askenv ( cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
extern char console_buffer[CONFIG_SYS_CBSIZE];
char message[CONFIG_SYS_CBSIZE];
int size = CONFIG_SYS_CBSIZE - 1;
int len;
char *local_args[4];
local_args[0] = argv[0];
local_args[1] = argv[1];
local_args[2] = NULL;
local_args[3] = NULL;
if (argc < 2) {
cmd_usage(cmdtp);
return 1;
}
/* Check the syntax */
switch (argc) {
case 1:
cmd_usage(cmdtp);
return 1;
case 2: /* askenv envname */
sprintf (message, "Please enter '%s':", argv[1]);
break;
case 3: /* askenv envname size */
sprintf (message, "Please enter '%s':", argv[1]);
size = simple_strtoul (argv[2], NULL, 10);
break;
default: /* askenv envname message1 ... messagen size */
{
int i;
int pos = 0;
for (i = 2; i < argc - 1; i++) {
if (pos) {
message[pos++] = ' ';
}
strcpy (message+pos, argv[i]);
pos += strlen(argv[i]);
}
message[pos] = '\0';
size = simple_strtoul (argv[argc - 1], NULL, 10);
}
break;
}
if (size >= CONFIG_SYS_CBSIZE)
size = CONFIG_SYS_CBSIZE - 1;
if (size <= 0)
return 1;
/* prompt for input */
len = readline (message);
if (size < len)
console_buffer[size] = '\0';
len = 2;
if (console_buffer[0] != '\0') {
local_args[2] = console_buffer;
len = 3;
}
/* Continue calling setenv code */
return _do_setenv (flag, len, local_args);
}
#endif
/************************************************************************
* Interactively edit an environment variable
*/
#if defined(CONFIG_CMD_EDITENV)
int do_editenv(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
char buffer[CONFIG_SYS_CBSIZE];
char *init_val;
int len;
if (argc < 2) {
cmd_usage(cmdtp);
return 1;
}
/* Set read buffer to initial value or empty sting */
init_val = getenv(argv[1]);
if (init_val)
len = sprintf(buffer, "%s", init_val);
else
buffer[0] = '\0';
readline_into_buffer("edit: ", buffer);
return setenv(argv[1], buffer);
}
#endif /* CONFIG_CMD_EDITENV */
/************************************************************************
* Look up variable from environment,
* return address of storage for that variable,
* or NULL if not found
*/
char *getenv (char *name)
{
int i, nxt;
WATCHDOG_RESET();
for (i=0; env_get_char(i) != '\0'; i=nxt+1) {
int val;
for (nxt=i; env_get_char(nxt) != '\0'; ++nxt) {
if (nxt >= CONFIG_ENV_SIZE) {
return (NULL);
}
}
if ((val=envmatch((uchar *)name, i)) < 0)
continue;
return ((char *)env_get_addr(val));
}
return (NULL);
}
int getenv_r (char *name, char *buf, unsigned len)
{
int i, nxt;
for (i=0; env_get_char(i) != '\0'; i=nxt+1) {
int val, n;
for (nxt=i; env_get_char(nxt) != '\0'; ++nxt) {
if (nxt >= CONFIG_ENV_SIZE) {
return (-1);
}
}
if ((val=envmatch((uchar *)name, i)) < 0)
continue;
/* found; copy out */
n = 0;
while ((len > n++) && (*buf++ = env_get_char(val++)) != '\0')
;
if (len == n)
*buf = '\0';
return (n);
}
return (-1);
}
#if defined(CONFIG_CMD_SAVEENV) && !defined(CONFIG_ENV_IS_NOWHERE)
int do_saveenv (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
extern char * env_name_spec;
printf ("Saving Environment to %s...\n", env_name_spec);
return (saveenv() ? 1 : 0);
}
U_BOOT_CMD(
saveenv, 1, 0, do_saveenv,
"save environment variables to persistent storage",
""
);
#endif
/************************************************************************
* Match a name / name=value pair
*
* s1 is either a simple 'name', or a 'name=value' pair.
* i2 is the environment index for a 'name2=value2' pair.
* If the names match, return the index for the value2, else NULL.
*/
int envmatch (uchar *s1, int i2)
{
while (*s1 == env_get_char(i2++))
if (*s1++ == '=')
return(i2);
if (*s1 == '\0' && env_get_char(i2-1) == '=')
return(i2);
return(-1);
}
/**************************************************/
#if defined(CONFIG_CMD_EDITENV)
U_BOOT_CMD(
editenv, 2, 0, do_editenv,
"edit environment variable",
"name\n"
" - edit environment variable 'name'"
);
#endif
U_BOOT_CMD(
printenv, CONFIG_SYS_MAXARGS, 1, do_printenv,
"print environment variables",
"\n - print values of all environment variables\n"
"printenv name ...\n"
" - print value of environment variable 'name'"
);
U_BOOT_CMD(
setenv, CONFIG_SYS_MAXARGS, 0, do_setenv,
"set environment variables",
"name value ...\n"
" - set environment variable 'name' to 'value ...'\n"
"setenv name\n"
" - delete environment variable 'name'"
);
#if defined(CONFIG_CMD_ASKENV)
U_BOOT_CMD(
askenv, CONFIG_SYS_MAXARGS, 1, do_askenv,
"get environment variables from stdin",
"name [message] [size]\n"
" - get environment variable 'name' from stdin (max 'size' chars)\n"
"askenv name\n"
" - get environment variable 'name' from stdin\n"
"askenv name size\n"
" - get environment variable 'name' from stdin (max 'size' chars)\n"
"askenv name [message] size\n"
" - display 'message' string and get environment variable 'name'"
"from stdin (max 'size' chars)"
);
#endif
#if defined(CONFIG_CMD_RUN)
int do_run (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]);
U_BOOT_CMD(
run, CONFIG_SYS_MAXARGS, 1, do_run,
"run commands in an environment variable",
"var [...]\n"
" - run the commands in the environment variable(s) 'var'"
);
#endif