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 42 static struct option long_options[] = { 43 {"script", required_argument, NULL, 's'}, 44 {"help", no_argument, NULL, 'h'}, 45 {NULL, 0, NULL, 0} 46 }; 47 48 struct common_args common_args; 49 struct printenv_args printenv_args; 50 struct setenv_args setenv_args; 51 52 void usage(void) 53 { 54 55 fprintf(stderr, "fw_printenv/fw_setenv, " 56 "a command line interface to U-Boot environment\n\n" 57 #ifndef CONFIG_FILE 58 "usage:\tfw_printenv [-a key] [-n] [variable name]\n" 59 "\tfw_setenv [-a key] [variable name] [variable value]\n" 60 #else 61 "usage:\tfw_printenv [-c /my/fw_env.config] [-a key] [-n] [variable name]\n" 62 "\tfw_setenv [-c /my/fw_env.config] [-a key] [variable name] [variable value]\n" 63 #endif 64 "\tfw_setenv -s [ file ]\n" 65 "\tfw_setenv -s - < [ file ]\n\n" 66 "The file passed as argument contains only pairs " 67 "name / value\n" 68 "Example:\n" 69 "# Any line starting with # is treated as comment\n" 70 "\n" 71 "\t netdev eth0\n" 72 "\t kernel_addr 400000\n" 73 "\t var1\n" 74 "\t var2 The quick brown fox jumps over the " 75 "lazy dog\n" 76 "\n" 77 "A variable without value will be dropped. It is possible\n" 78 "to put any number of spaces between the fields, but any\n" 79 "space inside the value is treated as part of the value " 80 "itself.\n\n" 81 ); 82 } 83 84 int parse_printenv_args(int argc, char *argv[]) 85 { 86 int c; 87 88 #ifdef CONFIG_FILE 89 common_args.config_file = CONFIG_FILE; 90 #endif 91 92 while ((c = getopt_long (argc, argv, "a:c:ns:h", 93 long_options, NULL)) != EOF) { 94 switch (c) { 95 case 'a': 96 if (parse_aes_key(optarg, common_args.aes_key)) { 97 fprintf(stderr, "AES key parse error\n"); 98 return EXIT_FAILURE; 99 } 100 common_args.aes_flag = 1; 101 break; 102 #ifdef CONFIG_FILE 103 case 'c': 104 common_args.config_file = optarg; 105 break; 106 #endif 107 case 'n': 108 printenv_args.name_suppress = 1; 109 break; 110 case 'h': 111 usage(); 112 exit(EXIT_SUCCESS); 113 break; 114 default: /* '?' */ 115 usage(); 116 exit(EXIT_FAILURE); 117 break; 118 } 119 } 120 return 0; 121 } 122 123 int parse_setenv_args(int argc, char *argv[]) 124 { 125 int c; 126 127 #ifdef CONFIG_FILE 128 common_args.config_file = CONFIG_FILE; 129 #endif 130 131 while ((c = getopt_long (argc, argv, "a:c:ns:h", 132 long_options, NULL)) != EOF) { 133 switch (c) { 134 case 'a': 135 if (parse_aes_key(optarg, common_args.aes_key)) { 136 fprintf(stderr, "AES key parse error\n"); 137 return EXIT_FAILURE; 138 } 139 common_args.aes_flag = 1; 140 break; 141 #ifdef CONFIG_FILE 142 case 'c': 143 common_args.config_file = optarg; 144 break; 145 #endif 146 case 's': 147 setenv_args.script_file = optarg; 148 break; 149 case 'h': 150 usage(); 151 exit(EXIT_SUCCESS); 152 break; 153 default: /* '?' */ 154 usage(); 155 exit(EXIT_FAILURE); 156 break; 157 } 158 } 159 return 0; 160 } 161 162 int main(int argc, char *argv[]) 163 { 164 char *cmdname = *argv; 165 const char *lockname = "/var/lock/" CMD_PRINTENV ".lock"; 166 int lockfd = -1; 167 int retval = EXIT_SUCCESS; 168 169 if (strrchr(cmdname, '/') != NULL) 170 cmdname = strrchr(cmdname, '/') + 1; 171 172 if (strcmp(cmdname, CMD_PRINTENV) == 0) { 173 if (parse_printenv_args(argc, argv)) 174 exit(EXIT_FAILURE); 175 } else if (strcmp(cmdname, CMD_SETENV) == 0) { 176 if (parse_setenv_args(argc, argv)) 177 exit(EXIT_FAILURE); 178 } else { 179 fprintf(stderr, 180 "Identity crisis - may be called as `%s' or as `%s' but not as `%s'\n", 181 CMD_PRINTENV, CMD_SETENV, cmdname); 182 exit(EXIT_FAILURE); 183 } 184 185 /* shift parsed flags, jump to non-option arguments */ 186 argc -= optind; 187 argv += optind; 188 189 lockfd = open(lockname, O_WRONLY | O_CREAT | O_TRUNC, 0666); 190 if (-1 == lockfd) { 191 fprintf(stderr, "Error opening lock file %s\n", lockname); 192 return EXIT_FAILURE; 193 } 194 195 if (-1 == flock(lockfd, LOCK_EX)) { 196 fprintf(stderr, "Error locking file %s\n", lockname); 197 close(lockfd); 198 return EXIT_FAILURE; 199 } 200 201 if (strcmp(cmdname, CMD_PRINTENV) == 0) { 202 if (fw_printenv(argc, argv) != 0) 203 retval = EXIT_FAILURE; 204 } else if (strcmp(cmdname, CMD_SETENV) == 0) { 205 if (!setenv_args.script_file) { 206 if (fw_setenv(argc, argv) != 0) 207 retval = EXIT_FAILURE; 208 } else { 209 if (fw_parse_script(setenv_args.script_file) != 0) 210 retval = EXIT_FAILURE; 211 } 212 } 213 214 flock(lockfd, LOCK_UN); 215 close(lockfd); 216 return retval; 217 } 218