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