gpt_uuid.c revision 1.16 
1/*	$NetBSD: gpt_uuid.c,v 1.16 2018/11/06 04:04:33 mrg Exp $	*/
2
3/*-
4 * Copyright (c) 2014 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
17 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
20 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26 * POSSIBILITY OF SUCH DAMAGE.
27 */
28
29#if HAVE_NBTOOL_CONFIG_H
30#include "nbtool_config.h"
31#endif
32
33#include <sys/cdefs.h>
34#ifdef __RCSID
35__RCSID("$NetBSD: gpt_uuid.c,v 1.16 2018/11/06 04:04:33 mrg Exp $");
36#endif
37
38#include <err.h>
39#include <fcntl.h>
40#include <stdio.h>
41#include <unistd.h>
42
43#include "map.h"
44#include "gpt.h"
45#include "gpt_private.h"
46
47#if defined(HAVE_SYS_ENDIAN_H) || ! defined(HAVE_NBTOOL_CONFIG_H)
48#include <sys/endian.h>
49#endif
50
51
52const gpt_uuid_t gpt_uuid_nil;
53
54struct dce_uuid {
55	uint32_t	time_low;
56	uint16_t	time_mid;
57	uint16_t	time_hi_and_version;
58	uint8_t		clock_seq_hi_and_reserved;
59	uint8_t		clock_seq_low;
60	uint8_t		node[6];
61};
62
63static const struct {
64	struct dce_uuid u;
65	const char *n;
66	const char *d;
67} gpt_nv[] = {
68	{ GPT_ENT_TYPE_APPLE_HFS, "apple", "Apple HFS" },
69	{ GPT_ENT_TYPE_APPLE_UFS, "apple-ufs", "Apple UFS" },
70	{ GPT_ENT_TYPE_BIOS, "bios", "BIOS Boot" },
71	{ GPT_ENT_TYPE_EFI, "efi", "EFI System" },
72	{ GPT_ENT_TYPE_FREEBSD, "fbsd-legacy", "FreeBSD legacy" },
73	{ GPT_ENT_TYPE_FREEBSD_SWAP, "fbsd-swap", "FreeBSD swap" },
74	{ GPT_ENT_TYPE_FREEBSD_UFS, "fbsd-ufs", "FreeBSD UFS/UFS2" },
75	{ GPT_ENT_TYPE_FREEBSD_VINUM, "fbsd-vinum", "FreeBSD vinum" },
76	{ GPT_ENT_TYPE_FREEBSD_ZFS, "fbsd-zfs", "FreeBSD ZFS" },
77	{ GPT_ENT_TYPE_LINUX_DATA, "linux-data", "Linux data" },
78	{ GPT_ENT_TYPE_LINUX_RAID, "linux-raid", "Linux RAID" },
79	{ GPT_ENT_TYPE_LINUX_SWAP, "linux-swap", "Linux swap" },
80	{ GPT_ENT_TYPE_LINUX_LVM, "linux-lvm", "Linux LVM" },
81	{ GPT_ENT_TYPE_MS_BASIC_DATA, "windows", "Windows basic data" },
82	{ GPT_ENT_TYPE_MS_RESERVED, "windows-reserved", "Windows reserved" },
83	{ GPT_ENT_TYPE_NETBSD_CCD, "ccd", "NetBSD ccd component" },
84	{ GPT_ENT_TYPE_NETBSD_CGD, "cgd", "NetBSD Cryptographic Disk" },
85	{ GPT_ENT_TYPE_NETBSD_FFS, "ffs", "NetBSD FFSv1/FFSv2" },
86	{ GPT_ENT_TYPE_NETBSD_LFS, "lfs", "NetBSD LFS" },
87	{ GPT_ENT_TYPE_NETBSD_RAIDFRAME, "raid",
88	    "NetBSD RAIDFrame component" },
89	{ GPT_ENT_TYPE_NETBSD_SWAP, "swap", "NetBSD swap" },
90	{ GPT_ENT_TYPE_VMWARE_VMKCORE, "swap", "VMware VMkernel core dump" },
91	{ GPT_ENT_TYPE_VMWARE_VMFS, "swap", "VMware VMFS" },
92	{ GPT_ENT_TYPE_VMWARE_RESERVED, "swap", "VMware reserved" },
93};
94
95static void
96gpt_uuid_to_dce(const gpt_uuid_t buf, struct dce_uuid *uuid)
97{
98	const uint8_t *p = buf;
99	size_t i;
100
101	uuid->time_low = le32dec(p);
102	uuid->time_mid = le16dec(p + 4);
103	uuid->time_hi_and_version = le16dec(p + 6);
104	uuid->clock_seq_hi_and_reserved = p[8];
105	uuid->clock_seq_low = p[9];
106	for (i = 0; i < sizeof(uuid->node); i++)
107		uuid->node[i] = p[10 + i];
108}
109
110static void
111gpt_dce_to_uuid(const struct dce_uuid *uuid, uint8_t *buf)
112{
113	uint8_t *p = buf;
114	size_t i;
115
116	le32enc(p, uuid->time_low);
117	le16enc(p + 4, uuid->time_mid);
118	le16enc(p + 6, uuid->time_hi_and_version);
119	p[8] = uuid->clock_seq_hi_and_reserved;
120	p[9] = uuid->clock_seq_low;
121	for (i = 0; i < sizeof(uuid->node); i++)
122		p[10 + i] = uuid->node[i];
123}
124
125static int
126gpt_uuid_numeric(char *buf, size_t bufsiz, const struct dce_uuid *u)
127{
128	return snprintf(buf, bufsiz,
129	    "%08x-%04x-%04x-%02x%02x-%02x%02x%02x%02x%02x%02x",
130	    u->time_low, u->time_mid, u->time_hi_and_version,
131	    u->clock_seq_hi_and_reserved, u->clock_seq_low, u->node[0],
132	    u->node[1], u->node[2], u->node[3], u->node[4], u->node[5]);
133}
134
135
136static int
137gpt_uuid_symbolic(char *buf, size_t bufsiz, const struct dce_uuid *u)
138{
139	size_t i;
140
141	for (i = 0; i < __arraycount(gpt_nv); i++)
142		if (memcmp(&gpt_nv[i].u, u, sizeof(*u)) == 0)
143			return (int)strlcpy(buf, gpt_nv[i].n, bufsiz);
144	return -1;
145}
146
147static int
148gpt_uuid_descriptive(char *buf, size_t bufsiz, const struct dce_uuid *u)
149{
150	size_t i;
151
152	for (i = 0; i < __arraycount(gpt_nv); i++)
153		if (memcmp(&gpt_nv[i].u, u, sizeof(*u)) == 0)
154			return (int)strlcpy(buf, gpt_nv[i].d, bufsiz);
155	return -1;
156}
157
158int
159gpt_uuid_snprintf(char *buf, size_t bufsiz, const char *fmt,
160    const gpt_uuid_t uu)
161{
162	struct dce_uuid u;
163	gpt_uuid_to_dce(uu, &u);
164
165	if (fmt[1] == 's') {
166		int r;
167		if ((r = gpt_uuid_symbolic(buf, bufsiz, &u)) != -1)
168			return r;
169	}
170	if (fmt[1] == 'l') {
171		int r;
172		if ((r = gpt_uuid_descriptive(buf, bufsiz, &u)) != -1)
173			return r;
174	}
175	return gpt_uuid_numeric(buf, bufsiz, &u);
176}
177
178static int
179gpt_uuid_parse_numeric(const char *s, struct dce_uuid *u)
180{
181	int n;
182
183	if (s == NULL || *s == '\0') {
184		memset(u, 0, sizeof(*u));
185		return 0;
186	}
187
188	n = sscanf(s,
189	    "%8x-%4hx-%4hx-%2hhx%2hhx-%2hhx%2hhx%2hhx%2hhx%2hhx%2hhx",
190	    &u->time_low, &u->time_mid, &u->time_hi_and_version,
191	    &u->clock_seq_hi_and_reserved, &u->clock_seq_low, &u->node[0],
192	    &u->node[1], &u->node[2], &u->node[3], &u->node[4], &u->node[5]);
193
194	/* Make sure we have all conversions. */
195	if (n != 11)
196		return -1;
197
198	/* We have a successful scan. Check semantics... */
199	n = u->clock_seq_hi_and_reserved;
200	if ((n & 0x80) != 0x00 &&			/* variant 0? */
201	    (n & 0xc0) != 0x80 &&			/* variant 1? */
202	    (n & 0xe0) != 0xc0) 			/* variant 2? */
203		return -1;
204	return 0;
205}
206
207static int
208gpt_uuid_parse_symbolic(const char *s, struct dce_uuid *u)
209{
210	size_t i;
211
212	for (i = 0; i < __arraycount(gpt_nv); i++)
213		if (strcmp(gpt_nv[i].n, s) == 0) {
214			*u = gpt_nv[i].u;
215			return 0;
216		}
217	return -1;
218}
219
220int
221gpt_uuid_parse(const char *s, gpt_uuid_t uuid)
222{
223	struct dce_uuid u;
224
225	if (gpt_uuid_parse_numeric(s, &u) != -1) {
226		gpt_dce_to_uuid(&u, uuid);
227		return 0;
228	}
229
230	if (gpt_uuid_parse_symbolic(s, &u) == -1)
231		return -1;
232
233	gpt_dce_to_uuid(&u, uuid);
234	return 0;
235}
236
237void
238gpt_uuid_help(const char *prefix)
239{
240	size_t i;
241
242	for (i = 0; i < __arraycount(gpt_nv); i++)
243		printf("%s%18.18s\t%s\n", prefix, gpt_nv[i].n, gpt_nv[i].d);
244}
245
246void
247gpt_uuid_create(gpt_type_t t, gpt_uuid_t u, uint16_t *b, size_t s)
248{
249	gpt_dce_to_uuid(&gpt_nv[t].u, u);
250	if (b)
251		utf8_to_utf16((const uint8_t *)gpt_nv[t].d, b, s / sizeof(*b));
252}
253
254static int
255gpt_uuid_random(gpt_t gpt, void *v, size_t n)
256{
257	int fd;
258	uint8_t *p;
259	ssize_t nread;
260
261	/* Randomly generate the content.  */
262	fd = open("/dev/urandom", O_RDONLY | O_CLOEXEC);
263	if (fd == -1) {
264		gpt_warn(gpt, "Can't open `/dev/urandom'");
265		return -1;
266	}
267	for (p = v;  n > 0; p += nread, n -= (size_t)nread) {
268		nread = read(fd, p, n);
269		if (nread < 0) {
270			gpt_warn(gpt, "Can't read `/dev/urandom'");
271			goto out;
272		}
273		if (nread == 0) {
274			gpt_warn(gpt, "EOF from /dev/urandom");
275			goto out;
276		}
277		if ((size_t)nread > n) {
278			gpt_warnx(gpt, "read too much: %zd > %zu", nread, n);
279			goto out;
280		}
281	}
282	(void)close(fd);
283	return 0;
284out:
285	(void)close(fd);
286	return -1;
287}
288
289static int
290gpt_uuid_tstamp(gpt_t gpt, void *v, size_t l)
291{
292	uint8_t *p;
293	// Perhaps use SHA?
294	uint32_t x = (uint32_t)gpt->timestamp;
295
296	for (p = v; l > 0; p += sizeof(x), l -= sizeof(x))
297		memcpy(p, &x, sizeof(x));
298
299	return 0;
300}
301
302int
303gpt_uuid_generate(gpt_t gpt, gpt_uuid_t t)
304{
305	int rv;
306	struct dce_uuid u;
307	if (gpt->flags & GPT_TIMESTAMP)
308		rv = gpt_uuid_tstamp(gpt, &u, sizeof(u));
309	else
310		rv = gpt_uuid_random(gpt, &u, sizeof(u));
311
312	if (rv == -1)
313		return -1;
314
315	/* Set the version number to 4.  */
316	u.time_hi_and_version &= (uint16_t)~0xf000;
317	u.time_hi_and_version |= 0x4000;
318
319	/* Fix the reserved bits.  */
320	u.clock_seq_hi_and_reserved &= (uint8_t)~0x40;
321	u.clock_seq_hi_and_reserved |= 0x80;
322
323	gpt_dce_to_uuid(&u, t);
324	return 0;
325}
326