summaryrefslogtreecommitdiff
path: root/tools/env/fw_env_main.c
blob: 0c9f918fc674a72236ac4e04469b208e07855a1c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
/*
 * (C) Copyright 2000-2008
 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

/*
 * Command line user interface to firmware (=U-Boot) environment.
 *
 * Implements:
 *	fw_printenv [ -a key ] [[ -n name ] | [ name ... ]]
 *              - prints the value of a single environment variable
 *                "name", the ``name=value'' pairs of one or more
 *                environment variables "name", or the whole
 *                environment if no names are specified.
 *	fw_setenv [ -a key ] name [ value ... ]
 *		- If a name without any values is given, the variable
 *		  with this name is deleted from the environment;
 *		  otherwise, all "value" arguments are concatenated,
 *		  separated by single blank characters, and the
 *		  resulting string is assigned to the environment
 *		  variable "name"
 *
 * If '-a key' is specified, the env block is encrypted with AES 128 CBC.
 * The 'key' argument is in the format of 32 hexadecimal numbers (16 bytes
 * of AES key), eg. '-a aabbccddeeff00112233445566778899'.
 */

#include <fcntl.h>
#include <getopt.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <sys/file.h>
#include <unistd.h>
#include "fw_env.h"

#define	CMD_PRINTENV	"fw_printenv"
#define CMD_SETENV	"fw_setenv"

static struct option long_options[] = {
	{"script", required_argument, NULL, 's'},
	{"help", no_argument, NULL, 'h'},
	{NULL, 0, NULL, 0}
};

struct printenv_args printenv_args;
struct setenv_args setenv_args;

void usage(void)
{

	fprintf(stderr, "fw_printenv/fw_setenv, "
		"a command line interface to U-Boot environment\n\n"
#ifndef CONFIG_FILE
		"usage:\tfw_printenv [-a key] [-n] [variable name]\n"
		"\tfw_setenv [-a key] [variable name] [variable value]\n"
#else
		"usage:\tfw_printenv [-c /my/fw_env.config] [-a key] [-n] [variable name]\n"
		"\tfw_setenv [-c /my/fw_env.config] [-a key] [variable name] [variable value]\n"
#endif
		"\tfw_setenv -s [ file ]\n"
		"\tfw_setenv -s - < [ file ]\n\n"
		"The file passed as argument contains only pairs "
		"name / value\n"
		"Example:\n"
		"# Any line starting with # is treated as comment\n"
		"\n"
		"\t      netdev         eth0\n"
		"\t      kernel_addr    400000\n"
		"\t      var1\n"
		"\t      var2          The quick brown fox jumps over the "
		"lazy dog\n"
		"\n"
		"A variable without value will be dropped. It is possible\n"
		"to put any number of spaces between the fields, but any\n"
		"space inside the value is treated as part of the value "
		"itself.\n\n"
	);
}

int parse_printenv_args(int argc, char *argv[])
{
	int c;

	while ((c = getopt_long (argc, argv, "a:c:ns:h",
		long_options, NULL)) != EOF) {
		switch (c) {
		case 'a':
			/* AES key, handled later */
			break;
		case 'c':
			/* handled later */
			break;
		case 'n':
			/* handled in fw_printenv */
			break;
		case 'h':
			usage();
			exit(EXIT_SUCCESS);
			break;
		default: /* '?' */
			usage();
			exit(EXIT_FAILURE);
			break;
		}
	}
	return 0;
}

int parse_setenv_args(int argc, char *argv[])
{
	int c;

	while ((c = getopt_long (argc, argv, "a:c:ns:h",
		long_options, NULL)) != EOF) {
		switch (c) {
		case 'a':
			/* AES key, handled later */
			break;
		case 'c':
			/* handled later */
			break;
		case 's':
			setenv_args.script_file = optarg;
			break;
		case 'h':
			usage();
			exit(EXIT_SUCCESS);
			break;
		default: /* '?' */
			usage();
			exit(EXIT_FAILURE);
			break;
		}
	}
	return 0;
}

int main(int argc, char *argv[])
{
	char *cmdname = *argv;
	const char *lockname = "/var/lock/" CMD_PRINTENV ".lock";
	int lockfd = -1;
	int retval = EXIT_SUCCESS;

	if (strrchr(cmdname, '/') != NULL)
		cmdname = strrchr(cmdname, '/') + 1;

	if (strcmp(cmdname, CMD_PRINTENV) == 0) {
		if (parse_printenv_args(argc, argv))
			exit(EXIT_FAILURE);
	} else if (strcmp(cmdname, CMD_SETENV) == 0) {
		if (parse_setenv_args(argc, argv))
			exit(EXIT_FAILURE);
	} else {
		fprintf(stderr,
			"Identity crisis - may be called as `%s' or as `%s' but not as `%s'\n",
			CMD_PRINTENV, CMD_SETENV, cmdname);
		exit(EXIT_FAILURE);
	}

	lockfd = open(lockname, O_WRONLY | O_CREAT | O_TRUNC, 0666);
	if (-1 == lockfd) {
		fprintf(stderr, "Error opening lock file %s\n", lockname);
		return EXIT_FAILURE;
	}

	if (-1 == flock(lockfd, LOCK_EX)) {
		fprintf(stderr, "Error locking file %s\n", lockname);
		close(lockfd);
		return EXIT_FAILURE;
	}

	if (strcmp(cmdname, CMD_PRINTENV) == 0) {
		if (fw_printenv(argc, argv) != 0)
			retval = EXIT_FAILURE;
	} else if (strcmp(cmdname, CMD_SETENV) == 0) {
		if (!setenv_args.script_file) {
			if (fw_setenv(argc, argv) != 0)
				retval = EXIT_FAILURE;
		} else {
			if (fw_parse_script(setenv_args.script_file) != 0)
				retval = EXIT_FAILURE;
		}
	}

	flock(lockfd, LOCK_UN);
	close(lockfd);
	return retval;
}