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 "fw_env.h" 38 39 #define CMD_PRINTENV "fw_printenv" 40 #define CMD_SETENV "fw_setenv" 41 static int do_printenv; 42 43 static struct option long_options[] = { 44 {"aes", required_argument, NULL, 'a'}, 45 {"config", required_argument, NULL, 'c'}, 46 {"help", no_argument, NULL, 'h'}, 47 {"script", required_argument, NULL, 's'}, 48 {"noheader", required_argument, NULL, 'n'}, 49 {"lock", required_argument, NULL, 'l'}, 50 {NULL, 0, NULL, 0} 51 }; 52 53 static struct env_opts env_opts; 54 55 /* setenv options */ 56 static int noheader; 57 58 /* getenv options */ 59 static char *script_file; 60 61 void usage_printenv(void) 62 { 63 64 fprintf(stderr, 65 "Usage: fw_printenv [OPTIONS]... [VARIABLE]...\n" 66 "Print variables from U-Boot environment\n" 67 "\n" 68 " -h, --help print this help.\n" 69 #ifdef CONFIG_ENV_AES 70 " -a, --aes aes key to access environment\n" 71 #endif 72 #ifdef CONFIG_FILE 73 " -c, --config configuration file, default:" CONFIG_FILE "\n" 74 #endif 75 " -n, --noheader do not repeat variable name in output\n" 76 " -l, --lock lock node, default:/var/lock\n" 77 "\n"); 78 } 79 80 void usage_setenv(void) 81 { 82 fprintf(stderr, 83 "Usage: fw_setenv [OPTIONS]... [VARIABLE]...\n" 84 "Modify variables in U-Boot environment\n" 85 "\n" 86 " -h, --help print this help.\n" 87 #ifdef CONFIG_ENV_AES 88 " -a, --aes aes key to access environment\n" 89 #endif 90 #ifdef CONFIG_FILE 91 " -c, --config configuration file, default:" CONFIG_FILE "\n" 92 #endif 93 " -l, --lock lock node, default:/var/lock\n" 94 " -s, --script batch mode to minimize writes\n" 95 "\n" 96 "Examples:\n" 97 " fw_setenv foo bar set variable foo equal bar\n" 98 " fw_setenv foo clear variable foo\n" 99 " fw_setenv --script file run batch script\n" 100 "\n" 101 "Script Syntax:\n" 102 " key [space] value\n" 103 " lines starting with '#' are treated as comment\n" 104 "\n" 105 " A variable without value will be deleted. Any number of spaces are\n" 106 " allowed between key and value. Space inside of the value is treated\n" 107 " as part of the value itself.\n" 108 "\n" 109 "Script Example:\n" 110 " netdev eth0\n" 111 " kernel_addr 400000\n" 112 " foo empty empty empty empty empty empty\n" 113 " bar\n" 114 "\n"); 115 } 116 117 static void parse_common_args(int argc, char *argv[]) 118 { 119 int c; 120 121 #ifdef CONFIG_FILE 122 env_opts.config_file = CONFIG_FILE; 123 #endif 124 125 while ((c = getopt_long(argc, argv, ":a:c:l:h", long_options, NULL)) != 126 EOF) { 127 switch (c) { 128 case 'a': 129 if (parse_aes_key(optarg, env_opts.aes_key)) { 130 fprintf(stderr, "AES key parse error\n"); 131 exit(EXIT_FAILURE); 132 } 133 env_opts.aes_flag = 1; 134 break; 135 #ifdef CONFIG_FILE 136 case 'c': 137 env_opts.config_file = optarg; 138 break; 139 #endif 140 case 'l': 141 env_opts.lockname = optarg; 142 break; 143 case 'h': 144 do_printenv ? usage_printenv() : usage_setenv(); 145 exit(EXIT_SUCCESS); 146 break; 147 default: 148 /* ignore unknown options */ 149 break; 150 } 151 } 152 153 /* Reset getopt for the next pass. */ 154 opterr = 1; 155 optind = 1; 156 } 157 158 int parse_printenv_args(int argc, char *argv[]) 159 { 160 int c; 161 162 parse_common_args(argc, argv); 163 164 while ((c = getopt_long(argc, argv, "a:c:ns:l:h", long_options, NULL)) 165 != EOF) { 166 switch (c) { 167 case 'n': 168 noheader = 1; 169 break; 170 case 'a': 171 case 'c': 172 case 'h': 173 case 'l': 174 /* ignore common options */ 175 break; 176 default: /* '?' */ 177 usage_printenv(); 178 exit(EXIT_FAILURE); 179 break; 180 } 181 } 182 return 0; 183 } 184 185 int parse_setenv_args(int argc, char *argv[]) 186 { 187 int c; 188 189 parse_common_args(argc, argv); 190 191 while ((c = getopt_long(argc, argv, "a:c:ns:l:h", long_options, NULL)) 192 != EOF) { 193 switch (c) { 194 case 's': 195 script_file = optarg; 196 break; 197 case 'a': 198 case 'c': 199 case 'h': 200 case 'l': 201 /* ignore common options */ 202 break; 203 default: /* '?' */ 204 usage_setenv(); 205 exit(EXIT_FAILURE); 206 break; 207 } 208 } 209 return 0; 210 } 211 212 int main(int argc, char *argv[]) 213 { 214 char *lockname = "/var/lock/" CMD_PRINTENV ".lock"; 215 int lockfd = -1; 216 int retval = EXIT_SUCCESS; 217 char *_cmdname; 218 219 _cmdname = *argv; 220 if (strrchr(_cmdname, '/') != NULL) 221 _cmdname = strrchr(_cmdname, '/') + 1; 222 223 if (strcmp(_cmdname, CMD_PRINTENV) == 0) { 224 do_printenv = 1; 225 } else if (strcmp(_cmdname, CMD_SETENV) == 0) { 226 do_printenv = 0; 227 } else { 228 fprintf(stderr, 229 "Identity crisis - may be called as `%s' or as `%s' but not as `%s'\n", 230 CMD_PRINTENV, CMD_SETENV, _cmdname); 231 exit(EXIT_FAILURE); 232 } 233 234 if (do_printenv) { 235 if (parse_printenv_args(argc, argv)) 236 exit(EXIT_FAILURE); 237 } else { 238 if (parse_setenv_args(argc, argv)) 239 exit(EXIT_FAILURE); 240 } 241 242 /* shift parsed flags, jump to non-option arguments */ 243 argc -= optind; 244 argv += optind; 245 246 if (env_opts.lockname) { 247 lockname = malloc(sizeof(env_opts.lockname) + 248 sizeof(CMD_PRINTENV) + 10); 249 if (!lockname) { 250 fprintf(stderr, "Unable allocate memory"); 251 exit(EXIT_FAILURE); 252 } 253 254 sprintf(lockname, "%s/%s.lock", 255 env_opts.lockname, CMD_PRINTENV); 256 } 257 258 lockfd = open(lockname, O_WRONLY | O_CREAT | O_TRUNC, 0666); 259 if (-1 == lockfd) { 260 fprintf(stderr, "Error opening lock file %s\n", lockname); 261 return EXIT_FAILURE; 262 } 263 264 if (-1 == flock(lockfd, LOCK_EX)) { 265 fprintf(stderr, "Error locking file %s\n", lockname); 266 close(lockfd); 267 return EXIT_FAILURE; 268 } 269 270 if (do_printenv) { 271 if (fw_printenv(argc, argv, noheader, &env_opts) != 0) 272 retval = EXIT_FAILURE; 273 } else { 274 if (!script_file) { 275 if (fw_setenv(argc, argv, &env_opts) != 0) 276 retval = EXIT_FAILURE; 277 } else { 278 if (fw_parse_script(script_file, &env_opts) != 0) 279 retval = EXIT_FAILURE; 280 } 281 } 282 283 if (env_opts.lockname) 284 free(lockname); 285 286 flock(lockfd, LOCK_UN); 287 close(lockfd); 288 return retval; 289 } 290