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_private.h" 38 #include "fw_env.h" 39 40 #define CMD_PRINTENV "fw_printenv" 41 #define CMD_SETENV "fw_setenv" 42 static int do_printenv; 43 44 static struct option long_options[] = { 45 {"aes", required_argument, NULL, 'a'}, 46 {"config", required_argument, NULL, 'c'}, 47 {"help", no_argument, NULL, 'h'}, 48 {"script", required_argument, NULL, 's'}, 49 {"noheader", required_argument, NULL, 'n'}, 50 {"lock", required_argument, NULL, 'l'}, 51 {NULL, 0, NULL, 0} 52 }; 53 54 static struct env_opts env_opts; 55 56 /* setenv options */ 57 static int noheader; 58 59 /* getenv options */ 60 static char *script_file; 61 62 void usage_printenv(void) 63 { 64 65 fprintf(stderr, 66 "Usage: fw_printenv [OPTIONS]... [VARIABLE]...\n" 67 "Print variables from U-Boot environment\n" 68 "\n" 69 " -h, --help print this help.\n" 70 #ifdef CONFIG_ENV_AES 71 " -a, --aes aes key to access environment\n" 72 #endif 73 #ifdef CONFIG_FILE 74 " -c, --config configuration file, default:" CONFIG_FILE "\n" 75 #endif 76 " -n, --noheader do not repeat variable name in output\n" 77 " -l, --lock lock node, default:/var/lock\n" 78 "\n"); 79 } 80 81 void usage_env_set(void) 82 { 83 fprintf(stderr, 84 "Usage: fw_setenv [OPTIONS]... [VARIABLE]...\n" 85 "Modify variables in U-Boot environment\n" 86 "\n" 87 " -h, --help print this help.\n" 88 #ifdef CONFIG_ENV_AES 89 " -a, --aes aes key to access environment\n" 90 #endif 91 #ifdef CONFIG_FILE 92 " -c, --config configuration file, default:" CONFIG_FILE "\n" 93 #endif 94 " -l, --lock lock node, default:/var/lock\n" 95 " -s, --script batch mode to minimize writes\n" 96 "\n" 97 "Examples:\n" 98 " fw_setenv foo bar set variable foo equal bar\n" 99 " fw_setenv foo clear variable foo\n" 100 " fw_setenv --script file run batch script\n" 101 "\n" 102 "Script Syntax:\n" 103 " key [space] value\n" 104 " lines starting with '#' are treated as comment\n" 105 "\n" 106 " A variable without value will be deleted. Any number of spaces are\n" 107 " allowed between key and value. Space inside of the value is treated\n" 108 " as part of the value itself.\n" 109 "\n" 110 "Script Example:\n" 111 " netdev eth0\n" 112 " kernel_addr 400000\n" 113 " foo empty empty empty empty empty empty\n" 114 " bar\n" 115 "\n"); 116 } 117 118 static void parse_common_args(int argc, char *argv[]) 119 { 120 int c; 121 122 #ifdef CONFIG_FILE 123 env_opts.config_file = CONFIG_FILE; 124 #endif 125 126 while ((c = getopt_long(argc, argv, ":a:c:l:h", long_options, NULL)) != 127 EOF) { 128 switch (c) { 129 case 'a': 130 if (parse_aes_key(optarg, env_opts.aes_key)) { 131 fprintf(stderr, "AES key parse error\n"); 132 exit(EXIT_FAILURE); 133 } 134 env_opts.aes_flag = 1; 135 break; 136 #ifdef CONFIG_FILE 137 case 'c': 138 env_opts.config_file = optarg; 139 break; 140 #endif 141 case 'l': 142 env_opts.lockname = optarg; 143 break; 144 case 'h': 145 do_printenv ? usage_printenv() : usage_env_set(); 146 exit(EXIT_SUCCESS); 147 break; 148 default: 149 /* ignore unknown options */ 150 break; 151 } 152 } 153 154 /* Reset getopt for the next pass. */ 155 opterr = 1; 156 optind = 1; 157 } 158 159 int parse_printenv_args(int argc, char *argv[]) 160 { 161 int c; 162 163 parse_common_args(argc, argv); 164 165 while ((c = getopt_long(argc, argv, "a:c:ns:l:h", long_options, NULL)) 166 != EOF) { 167 switch (c) { 168 case 'n': 169 noheader = 1; 170 break; 171 case 'a': 172 case 'c': 173 case 'h': 174 case 'l': 175 /* ignore common options */ 176 break; 177 default: /* '?' */ 178 usage_printenv(); 179 exit(EXIT_FAILURE); 180 break; 181 } 182 } 183 return 0; 184 } 185 186 int parse_setenv_args(int argc, char *argv[]) 187 { 188 int c; 189 190 parse_common_args(argc, argv); 191 192 while ((c = getopt_long(argc, argv, "a:c:ns:l:h", long_options, NULL)) 193 != EOF) { 194 switch (c) { 195 case 's': 196 script_file = optarg; 197 break; 198 case 'a': 199 case 'c': 200 case 'h': 201 case 'l': 202 /* ignore common options */ 203 break; 204 default: /* '?' */ 205 usage_env_set(); 206 exit(EXIT_FAILURE); 207 break; 208 } 209 } 210 return 0; 211 } 212 213 int main(int argc, char *argv[]) 214 { 215 char *lockname = "/var/lock/" CMD_PRINTENV ".lock"; 216 int lockfd = -1; 217 int retval = EXIT_SUCCESS; 218 char *_cmdname; 219 220 _cmdname = *argv; 221 if (strrchr(_cmdname, '/') != NULL) 222 _cmdname = strrchr(_cmdname, '/') + 1; 223 224 if (strcmp(_cmdname, CMD_PRINTENV) == 0) { 225 do_printenv = 1; 226 } else if (strcmp(_cmdname, CMD_SETENV) == 0) { 227 do_printenv = 0; 228 } else { 229 fprintf(stderr, 230 "Identity crisis - may be called as `%s' or as `%s' but not as `%s'\n", 231 CMD_PRINTENV, CMD_SETENV, _cmdname); 232 exit(EXIT_FAILURE); 233 } 234 235 if (do_printenv) { 236 if (parse_printenv_args(argc, argv)) 237 exit(EXIT_FAILURE); 238 } else { 239 if (parse_setenv_args(argc, argv)) 240 exit(EXIT_FAILURE); 241 } 242 243 /* shift parsed flags, jump to non-option arguments */ 244 argc -= optind; 245 argv += optind; 246 247 if (env_opts.lockname) { 248 lockname = malloc(sizeof(env_opts.lockname) + 249 sizeof(CMD_PRINTENV) + 10); 250 if (!lockname) { 251 fprintf(stderr, "Unable allocate memory"); 252 exit(EXIT_FAILURE); 253 } 254 255 sprintf(lockname, "%s/%s.lock", 256 env_opts.lockname, CMD_PRINTENV); 257 } 258 259 lockfd = open(lockname, O_WRONLY | O_CREAT | O_TRUNC, 0666); 260 if (-1 == lockfd) { 261 fprintf(stderr, "Error opening lock file %s\n", lockname); 262 return EXIT_FAILURE; 263 } 264 265 if (-1 == flock(lockfd, LOCK_EX)) { 266 fprintf(stderr, "Error locking file %s\n", lockname); 267 close(lockfd); 268 return EXIT_FAILURE; 269 } 270 271 if (do_printenv) { 272 if (fw_printenv(argc, argv, noheader, &env_opts) != 0) 273 retval = EXIT_FAILURE; 274 } else { 275 if (!script_file) { 276 if (fw_env_set(argc, argv, &env_opts) != 0) 277 retval = EXIT_FAILURE; 278 } else { 279 if (fw_parse_script(script_file, &env_opts) != 0) 280 retval = EXIT_FAILURE; 281 } 282 } 283 284 if (env_opts.lockname) 285 free(lockname); 286 287 flock(lockfd, LOCK_UN); 288 close(lockfd); 289 return retval; 290 } 291