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 void usage(void) 49 { 50 51 fprintf(stderr, "fw_printenv/fw_setenv, " 52 "a command line interface to U-Boot environment\n\n" 53 #ifndef CONFIG_FILE 54 "usage:\tfw_printenv [-a key] [-n] [variable name]\n" 55 "\tfw_setenv [-a key] [variable name] [variable value]\n" 56 #else 57 "usage:\tfw_printenv [-c /my/fw_env.config] [-a key] [-n] [variable name]\n" 58 "\tfw_setenv [-c /my/fw_env.config] [-a key] [variable name] [variable value]\n" 59 #endif 60 "\tfw_setenv -s [ file ]\n" 61 "\tfw_setenv -s - < [ file ]\n\n" 62 "The file passed as argument contains only pairs " 63 "name / value\n" 64 "Example:\n" 65 "# Any line starting with # is treated as comment\n" 66 "\n" 67 "\t netdev eth0\n" 68 "\t kernel_addr 400000\n" 69 "\t var1\n" 70 "\t var2 The quick brown fox jumps over the " 71 "lazy dog\n" 72 "\n" 73 "A variable without value will be dropped. It is possible\n" 74 "to put any number of spaces between the fields, but any\n" 75 "space inside the value is treated as part of the value " 76 "itself.\n\n" 77 ); 78 } 79 80 int main(int argc, char *argv[]) 81 { 82 char *p; 83 char *cmdname = *argv; 84 char *script_file = NULL; 85 int c; 86 const char *lockname = "/var/lock/" CMD_PRINTENV ".lock"; 87 int lockfd = -1; 88 int retval = EXIT_SUCCESS; 89 90 lockfd = open(lockname, O_WRONLY | O_CREAT | O_TRUNC, 0666); 91 if (-1 == lockfd) { 92 fprintf(stderr, "Error opening lock file %s\n", lockname); 93 return EXIT_FAILURE; 94 } 95 96 if (-1 == flock(lockfd, LOCK_EX)) { 97 fprintf(stderr, "Error locking file %s\n", lockname); 98 close(lockfd); 99 return EXIT_FAILURE; 100 } 101 102 if ((p = strrchr (cmdname, '/')) != NULL) { 103 cmdname = p + 1; 104 } 105 106 while ((c = getopt_long (argc, argv, "a:c:ns:h", 107 long_options, NULL)) != EOF) { 108 switch (c) { 109 case 'a': 110 /* AES key, handled later */ 111 break; 112 case 'c': 113 /* handled later */ 114 break; 115 case 'n': 116 /* handled in fw_printenv */ 117 break; 118 case 's': 119 script_file = optarg; 120 break; 121 case 'h': 122 usage(); 123 goto exit; 124 default: /* '?' */ 125 fprintf(stderr, "Try `%s --help' for more information." 126 "\n", cmdname); 127 retval = EXIT_FAILURE; 128 goto exit; 129 } 130 } 131 132 if (strcmp(cmdname, CMD_PRINTENV) == 0) { 133 if (fw_printenv(argc, argv) != 0) 134 retval = EXIT_FAILURE; 135 } else if (strcmp(cmdname, CMD_SETENV) == 0) { 136 if (!script_file) { 137 if (fw_setenv(argc, argv) != 0) 138 retval = EXIT_FAILURE; 139 } else { 140 if (fw_parse_script(script_file) != 0) 141 retval = EXIT_FAILURE; 142 } 143 } else { 144 fprintf(stderr, 145 "Identity crisis - may be called as `" CMD_PRINTENV 146 "' or as `" CMD_SETENV "' but not as `%s'\n", 147 cmdname); 148 retval = EXIT_FAILURE; 149 } 150 151 exit: 152 flock(lockfd, LOCK_UN); 153 close(lockfd); 154 return retval; 155 } 156