efidp.c revision 318576 
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: stable/11/usr.sbin/efidp/efidp.c 314928 2017-03-09 00:33:38Z imp $");
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 */
41static struct option longopts[] = {
42	{ "format",		no_argument,		NULL,	'f' },
43	{ "parse",		no_argument,		NULL,	'p' },
44	{ NULL,			0,			NULL,	0 }
45};
46
47
48static int flag_format, flag_parse;
49
50static void
51usage(void)
52{
53
54	errx(1, "efidp [-fp]");
55}
56
57static ssize_t
58read_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
83static void
84parse_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
114int
115main(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