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