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