tools/env/fw_env_main.c

   1 /*
   2  * (C) Copyright 2000-2008
   3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   4  *
   5  * SPDX-License-Identifier:     GPL-2.0+
   6  */
   7
   8 /*
   9  * Command line user interface to firmware (=U-Boot) environment.
  10  *
  11  * Implements:
  12  *      fw_printenv [ -a key ] [[ -n name ] | [ name ... ]]
  13  *              - prints the value of a single environment variable
  14  *                "name", the ``name=value'' pairs of one or more
  15  *                environment variables "name", or the whole
  16  *                environment if no names are specified.
  17  *      fw_setenv [ -a key ] name [ value ... ]
  18  *              - If a name without any values is given, the variable
  19  *                with this name is deleted from the environment;
  20  *                otherwise, all "value" arguments are concatenated,
  21  *                separated by single blank characters, and the
  22  *                resulting string is assigned to the environment
  23  *                variable "name"
  24  *
  25  * If '-a key' is specified, the env block is encrypted with AES 128 CBC.
  26  * The 'key' argument is in the format of 32 hexadecimal numbers (16 bytes
  27  * of AES key), eg. '-a aabbccddeeff00112233445566778899'.
  28  */
  29
  30 #include <fcntl.h>
  31 #include <getopt.h>
  32 #include <stdio.h>
  33 #include <string.h>
  34 #include <stdlib.h>
  35 #include <sys/file.h>
  36 #include <unistd.h>
  37 #include <version.h>
  38 #include "fw_env_private.h"
  39 #include "fw_env.h"
  40
  41 #define CMD_PRINTENV    "fw_printenv"
  42 #define CMD_SETENV      "fw_setenv"
  43 static int do_printenv;
  44
  45 static struct option long_options[] = {
  46         {"aes", required_argument, NULL, 'a'},
  47         {"config", required_argument, NULL, 'c'},
  48         {"help", no_argument, NULL, 'h'},
  49         {"script", required_argument, NULL, 's'},
  50         {"noheader", required_argument, NULL, 'n'},
  51         {"lock", required_argument, NULL, 'l'},
  52         {"version", no_argument, NULL, 'v'},
  53         {NULL, 0, NULL, 0}
  54 };
  55
  56 static struct env_opts env_opts;
  57
  58 /* setenv options */
  59 static int noheader;
  60
  61 /* getenv options */
  62 static char *script_file;
  63
  64 void usage_printenv(void)
  65 {
  66
  67         fprintf(stderr,
  68                 "Usage: fw_printenv [OPTIONS]... [VARIABLE]...\n"
  69                 "Print variables from U-Boot environment\n"
  70                 "\n"
  71                 " -h, --help           print this help.\n"
  72                 " -v, --version        display version\n"
  73 #ifdef CONFIG_ENV_AES
  74                 " -a, --aes            aes key to access environment\n"
  75 #endif
  76 #ifdef CONFIG_FILE
  77                 " -c, --config         configuration file, default:" CONFIG_FILE "\n"
  78 #endif
  79                 " -n, --noheader       do not repeat variable name in output\n"
  80                 " -l, --lock           lock node, default:/var/lock\n"
  81                 "\n");
  82 }
  83
  84 void usage_env_set(void)
  85 {
  86         fprintf(stderr,
  87                 "Usage: fw_setenv [OPTIONS]... [VARIABLE]...\n"
  88                 "Modify variables in U-Boot environment\n"
  89                 "\n"
  90                 " -h, --help           print this help.\n"
  91                 " -v, --version        display version\n"
  92 #ifdef CONFIG_ENV_AES
  93                 " -a, --aes            aes key to access environment\n"
  94 #endif
  95 #ifdef CONFIG_FILE
  96                 " -c, --config         configuration file, default:" CONFIG_FILE "\n"
  97 #endif
  98                 " -l, --lock           lock node, default:/var/lock\n"
  99                 " -s, --script         batch mode to minimize writes\n"
 100                 "\n"
 101                 "Examples:\n"
 102                 "  fw_setenv foo bar   set variable foo equal bar\n"
 103                 "  fw_setenv foo       clear variable foo\n"
 104                 "  fw_setenv --script file run batch script\n"
 105                 "\n"
 106                 "Script Syntax:\n"
 107                 "  key [space] value\n"
 108                 "  lines starting with '#' are treated as comment\n"
 109                 "\n"
 110                 "  A variable without value will be deleted. Any number of spaces are\n"
 111                 "  allowed between key and value. Space inside of the value is treated\n"
 112                 "  as part of the value itself.\n"
 113                 "\n"
 114                 "Script Example:\n"
 115                 "  netdev         eth0\n"
 116                 "  kernel_addr    400000\n"
 117                 "  foo            empty empty empty    empty empty empty\n"
 118                 "  bar\n"
 119                 "\n");
 120 }
 121
 122 static void parse_common_args(int argc, char *argv[])
 123 {
 124         int c;
 125
 126 #ifdef CONFIG_FILE
 127         env_opts.config_file = CONFIG_FILE;
 128 #endif
 129
 130         while ((c = getopt_long(argc, argv, ":a:c:l:h:v", long_options, NULL)) !=
 131                EOF) {
 132                 switch (c) {
 133                 case 'a':
 134                         if (parse_aes_key(optarg, env_opts.aes_key)) {
 135                                 fprintf(stderr, "AES key parse error\n");
 136                                 exit(EXIT_FAILURE);
 137                         }
 138                         env_opts.aes_flag = 1;
 139                         break;
 140 #ifdef CONFIG_FILE
 141                 case 'c':
 142                         env_opts.config_file = optarg;
 143                         break;
 144 #endif
 145                 case 'l':
 146                         env_opts.lockname = optarg;
 147                         break;
 148                 case 'h':
 149                         do_printenv ? usage_printenv() : usage_env_set();
 150                         exit(EXIT_SUCCESS);
 151                         break;
 152                 case 'v':
 153                         fprintf(stderr, "Compiled with " U_BOOT_VERSION "\n");
 154                         exit(EXIT_SUCCESS);
 155                         break;
 156                 default:
 157                         /* ignore unknown options */
 158                         break;
 159                 }
 160         }
 161
 162         /* Reset getopt for the next pass. */
 163         opterr = 1;
 164         optind = 1;
 165 }
 166
 167 int parse_printenv_args(int argc, char *argv[])
 168 {
 169         int c;
 170
 171         parse_common_args(argc, argv);
 172
 173         while ((c = getopt_long(argc, argv, "a:c:ns:l:h:v", long_options, NULL))
 174                 != EOF) {
 175                 switch (c) {
 176                 case 'n':
 177                         noheader = 1;
 178                         break;
 179                 case 'a':
 180                 case 'c':
 181                 case 'h':
 182                 case 'l':
 183                         /* ignore common options */
 184                         break;
 185                 default: /* '?' */
 186                         usage_printenv();
 187                         exit(EXIT_FAILURE);
 188                         break;
 189                 }
 190         }
 191         return 0;
 192 }
 193
 194 int parse_setenv_args(int argc, char *argv[])
 195 {
 196         int c;
 197
 198         parse_common_args(argc, argv);
 199
 200         while ((c = getopt_long(argc, argv, "a:c:ns:l:h:v", long_options, NULL))
 201                 != EOF) {
 202                 switch (c) {
 203                 case 's':
 204                         script_file = optarg;
 205                         break;
 206                 case 'a':
 207                 case 'c':
 208                 case 'h':
 209                 case 'l':
 210                         /* ignore common options */
 211                         break;
 212                 default: /* '?' */
 213                         usage_env_set();
 214                         exit(EXIT_FAILURE);
 215                         break;
 216                 }
 217         }
 218         return 0;
 219 }
 220
 221 int main(int argc, char *argv[])
 222 {
 223         char *lockname = "/var/lock/" CMD_PRINTENV ".lock";
 224         int lockfd = -1;
 225         int retval = EXIT_SUCCESS;
 226         char *_cmdname;
 227
 228         _cmdname = *argv;
 229         if (strrchr(_cmdname, '/') != NULL)
 230                 _cmdname = strrchr(_cmdname, '/') + 1;
 231
 232         if (strcmp(_cmdname, CMD_PRINTENV) == 0) {
 233                 do_printenv = 1;
 234         } else if (strcmp(_cmdname, CMD_SETENV) == 0) {
 235                 do_printenv = 0;
 236         } else {
 237                 fprintf(stderr,
 238                         "Identity crisis - may be called as `%s' or as `%s' but not as `%s'\n",
 239                         CMD_PRINTENV, CMD_SETENV, _cmdname);
 240                 exit(EXIT_FAILURE);
 241         }
 242
 243         if (do_printenv) {
 244                 if (parse_printenv_args(argc, argv))
 245                         exit(EXIT_FAILURE);
 246         } else {
 247                 if (parse_setenv_args(argc, argv))
 248                         exit(EXIT_FAILURE);
 249         }
 250
 251         /* shift parsed flags, jump to non-option arguments */
 252         argc -= optind;
 253         argv += optind;
 254
 255         if (env_opts.lockname) {
 256                 lockname = malloc(sizeof(env_opts.lockname) +
 257                                 sizeof(CMD_PRINTENV) + 10);
 258                 if (!lockname) {
 259                         fprintf(stderr, "Unable allocate memory");
 260                         exit(EXIT_FAILURE);
 261                 }
 262
 263                 sprintf(lockname, "%s/%s.lock",
 264                         env_opts.lockname, CMD_PRINTENV);
 265         }
 266
 267         lockfd = open(lockname, O_WRONLY | O_CREAT | O_TRUNC, 0666);
 268         if (-1 == lockfd) {
 269                 fprintf(stderr, "Error opening lock file %s\n", lockname);
 270                 return EXIT_FAILURE;
 271         }
 272
 273         if (-1 == flock(lockfd, LOCK_EX)) {
 274                 fprintf(stderr, "Error locking file %s\n", lockname);
 275                 close(lockfd);
 276                 return EXIT_FAILURE;
 277         }
 278
 279         if (do_printenv) {
 280                 if (fw_printenv(argc, argv, noheader, &env_opts) != 0)
 281                         retval = EXIT_FAILURE;
 282         } else {
 283                 if (!script_file) {
 284                         if (fw_env_set(argc, argv, &env_opts) != 0)
 285                                 retval = EXIT_FAILURE;
 286                 } else {
 287                         if (fw_parse_script(script_file, &env_opts) != 0)
 288                                 retval = EXIT_FAILURE;
 289                 }
 290         }
 291
 292         if (env_opts.lockname)
 293                 free(lockname);
 294
 295         flock(lockfd, LOCK_UN);
 296         close(lockfd);
 297         return retval;
 298 }