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