xref: /freebsd/usr.sbin/efidp/efidp.c (revision d6b92ffa)
1 /*-
2  * Copyright (c) 2016 Netflix, Inc.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <efivar.h>
31 #include <efivar-dp.h>
32 #include <err.h>
33 #include <getopt.h>
34 #include <stddef.h>
35 #include <stdio.h>
36 #include <stdlib.h>
37 #include <string.h>
38 #include <unistd.h>
39 
40 /* options descriptor */
41 static struct option longopts[] = {
42 	{ "format",		no_argument,		NULL,	'f' },
43 	{ "parse",		no_argument,		NULL,	'p' },
44 	{ NULL,			0,			NULL,	0 }
45 };
46 
47 
48 static int flag_format, flag_parse;
49 
50 static void
51 usage(void)
52 {
53 
54 	errx(1, "efidp [-fp]");
55 }
56 
57 static ssize_t
58 read_file(int fd, void **rv)
59 {
60 	uint8_t *retval;
61 	size_t len;
62 	off_t off;
63 	ssize_t red;
64 
65 	len = 4096;
66 	off = 0;
67 	retval = malloc(len);
68 	do {
69 		red = read(fd, retval + off, len - off);
70 		off += red;
71 		if (red < (ssize_t)(len - off))
72 			break;
73 		len *= 2;
74 		retval = reallocf(retval, len);
75 		if (retval == NULL)
76 			return -1;
77 	} while (1);
78 	*rv = retval;
79 
80 	return off;
81 }
82 
83 static void
84 parse_args(int argc, char **argv)
85 {
86 	int ch;
87 
88 	while ((ch = getopt_long(argc, argv, "fp",
89 		    longopts, NULL)) != -1) {
90 		switch (ch) {
91 		case 'f':
92 			flag_format++;
93 			break;
94 		case 'p':
95 			flag_parse++;
96 			break;
97 		default:
98 			usage();
99 		}
100 	}
101 	argc -= optind;
102 	argv += optind;
103 
104 	if (argc >= 1)
105 		usage();
106 
107 	if (flag_parse + flag_format != 1) {
108 		warnx("Can only use one of -p (--parse), "
109 		    "and -f (--format)");
110 		usage();
111 	}
112 }
113 
114 int
115 main(int argc, char **argv)
116 {
117 	void *data;
118 	ssize_t len;
119 
120 	parse_args(argc, argv);
121 	len = read_file(STDIN_FILENO, &data);
122 	if (len == -1)
123 		err(1, "read");
124 	if (flag_format) {
125 		char buffer[4096];
126 		ssize_t fmtlen;
127 
128 		fmtlen = efidp_format_device_path(buffer, sizeof(buffer),
129 		    (const_efidp)data, len);
130 		if (fmtlen > 0)
131 			printf("%s\n", buffer);
132 		free(data);
133 	} else if (flag_parse) {
134 		efidp dp;
135 		ssize_t dplen;
136 		char *str;
137 
138 		dp = malloc(8192);
139 		str = realloc(data, len + 1);
140 		if (str == NULL || dp == NULL)
141 			errx(1, "Can't allocate memory.");
142 		str[len] = '\0';
143 		dplen = efidp_parse_device_path(str, dp, 8192);
144 		if (dplen == -1)
145 			errx(1, "Can't parse %s", str);
146 		write(STDOUT_FILENO, dp, dplen);
147 	}
148 }
149