u-boot/tools/env/fw_env_main.c

267 lines
6.1 KiB
C
Raw Normal View History

/*
* (C) Copyright 2000-2008
* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
*
* SPDX-License-Identifier: GPL-2.0+
*/
/*
* Command line user interface to firmware (=U-Boot) environment.
*
* Implements:
* fw_printenv [ -a key ] [[ -n name ] | [ name ... ]]
* - prints the value of a single environment variable
* "name", the ``name=value'' pairs of one or more
* environment variables "name", or the whole
* environment if no names are specified.
* fw_setenv [ -a key ] name [ value ... ]
* - If a name without any values is given, the variable
* with this name is deleted from the environment;
* otherwise, all "value" arguments are concatenated,
* separated by single blank characters, and the
* resulting string is assigned to the environment
* variable "name"
*
* If '-a key' is specified, the env block is encrypted with AES 128 CBC.
* The 'key' argument is in the format of 32 hexadecimal numbers (16 bytes
* of AES key), eg. '-a aabbccddeeff00112233445566778899'.
*/
#include <fcntl.h>
#include <getopt.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <sys/file.h>
#include <unistd.h>
#include "fw_env.h"
#define CMD_PRINTENV "fw_printenv"
#define CMD_SETENV "fw_setenv"
static int do_printenv;
static struct option long_options[] = {
{"aes", required_argument, NULL, 'a'},
{"config", required_argument, NULL, 'c'},
{"help", no_argument, NULL, 'h'},
{"script", required_argument, NULL, 's'},
{"noheader", required_argument, NULL, 'n'},
{NULL, 0, NULL, 0}
};
static struct env_opts env_opts;
/* setenv options */
static int noheader;
/* getenv options */
static char *script_file;
void usage_printenv(void)
{
fprintf(stderr,
"Usage: fw_printenv [OPTIONS]... [VARIABLE]...\n"
"Print variables from U-Boot environment\n"
"\n"
" -h, --help print this help.\n"
#ifdef CONFIG_ENV_AES
" -a, --aes aes key to access environment\n"
#endif
#ifdef CONFIG_FILE
" -c, --config configuration file, default:" CONFIG_FILE "\n"
#endif
" -n, --noheader do not repeat variable name in output\n"
"\n");
}
void usage_setenv(void)
{
fprintf(stderr,
"Usage: fw_setenv [OPTIONS]... [VARIABLE]...\n"
"Modify variables in U-Boot environment\n"
"\n"
" -h, --help print this help.\n"
#ifdef CONFIG_ENV_AES
" -a, --aes aes key to access environment\n"
#endif
#ifdef CONFIG_FILE
" -c, --config configuration file, default:" CONFIG_FILE "\n"
#endif
" -s, --script batch mode to minimize writes\n"
"\n"
"Examples:\n"
" fw_setenv foo bar set variable foo equal bar\n"
" fw_setenv foo clear variable foo\n"
" fw_setenv --script file run batch script\n"
"\n"
"Script Syntax:\n"
" key [space] value\n"
" lines starting with '#' are treated as comment\n"
"\n"
" A variable without value will be deleted. Any number of spaces are\n"
" allowed between key and value. Space inside of the value is treated\n"
" as part of the value itself.\n"
"\n"
"Script Example:\n"
" netdev eth0\n"
" kernel_addr 400000\n"
" foo empty empty empty empty empty empty\n"
" bar\n"
"\n");
}
static void parse_common_args(int argc, char *argv[])
{
int c;
#ifdef CONFIG_FILE
env_opts.config_file = CONFIG_FILE;
#endif
while ((c = getopt_long(argc, argv, ":a:c:h", long_options, NULL)) !=
EOF) {
switch (c) {
case 'a':
if (parse_aes_key(optarg, env_opts.aes_key)) {
fprintf(stderr, "AES key parse error\n");
exit(EXIT_FAILURE);
}
env_opts.aes_flag = 1;
break;
#ifdef CONFIG_FILE
case 'c':
env_opts.config_file = optarg;
break;
#endif
case 'h':
do_printenv ? usage_printenv() : usage_setenv();
exit(EXIT_SUCCESS);
break;
default:
/* ignore unknown options */
break;
}
}
/* Reset getopt for the next pass. */
opterr = 1;
optind = 1;
}
int parse_printenv_args(int argc, char *argv[])
{
int c;
parse_common_args(argc, argv);
while ((c = getopt_long(argc, argv, "a:c:ns:h", long_options, NULL)) !=
EOF) {
switch (c) {
case 'n':
noheader = 1;
break;
case 'a':
case 'c':
case 'h':
/* ignore common options */
break;
default: /* '?' */
usage_printenv();
exit(EXIT_FAILURE);
break;
}
}
return 0;
}
int parse_setenv_args(int argc, char *argv[])
{
int c;
parse_common_args(argc, argv);
while ((c = getopt_long(argc, argv, "a:c:ns:h", long_options, NULL)) !=
EOF) {
switch (c) {
case 's':
script_file = optarg;
break;
case 'a':
case 'c':
case 'h':
/* ignore common options */
break;
default: /* '?' */
usage_setenv();
exit(EXIT_FAILURE);
break;
}
}
return 0;
}
int main(int argc, char *argv[])
{
const char *lockname = "/var/lock/" CMD_PRINTENV ".lock";
int lockfd = -1;
int retval = EXIT_SUCCESS;
char *_cmdname;
_cmdname = *argv;
if (strrchr(_cmdname, '/') != NULL)
_cmdname = strrchr(_cmdname, '/') + 1;
if (strcmp(_cmdname, CMD_PRINTENV) == 0) {
do_printenv = 1;
} else if (strcmp(_cmdname, CMD_SETENV) == 0) {
do_printenv = 0;
} else {
fprintf(stderr,
"Identity crisis - may be called as `%s' or as `%s' but not as `%s'\n",
CMD_PRINTENV, CMD_SETENV, _cmdname);
exit(EXIT_FAILURE);
}
if (do_printenv) {
if (parse_printenv_args(argc, argv))
exit(EXIT_FAILURE);
} else {
if (parse_setenv_args(argc, argv))
exit(EXIT_FAILURE);
}
/* shift parsed flags, jump to non-option arguments */
argc -= optind;
argv += optind;
lockfd = open(lockname, O_WRONLY | O_CREAT | O_TRUNC, 0666);
if (-1 == lockfd) {
fprintf(stderr, "Error opening lock file %s\n", lockname);
return EXIT_FAILURE;
}
if (-1 == flock(lockfd, LOCK_EX)) {
fprintf(stderr, "Error locking file %s\n", lockname);
close(lockfd);
return EXIT_FAILURE;
}
if (do_printenv) {
if (fw_printenv(argc, argv, noheader, &env_opts) != 0)
retval = EXIT_FAILURE;
} else {
if (!script_file) {
if (fw_setenv(argc, argv, &env_opts) != 0)
retval = EXIT_FAILURE;
} else {
if (fw_parse_script(script_file, &env_opts) != 0)
retval = EXIT_FAILURE;
}
}
flock(lockfd, LOCK_UN);
close(lockfd);
return retval;
}