gpt.c revision 263466
1/*-
2 * Copyright (c) 2014 Juniper Networks, 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: user/marcel/mkimg/gpt.c 263466 2014-03-21 05:30:27Z marcel $");
29
30#include <sys/types.h>
31#include <sys/diskmbr.h>
32#include <sys/endian.h>
33#include <sys/errno.h>
34#include <sys/gpt.h>
35#include <stddef.h>
36#include <stdint.h>
37#include <stdlib.h>
38#include <string.h>
39#include <unistd.h>
40#include <uuid.h>
41
42#include "mkimg.h"
43#include "scheme.h"
44
45static uuid_t gpt_uuid_efi = GPT_ENT_TYPE_EFI;
46
47static struct mkimg_alias gpt_aliases[] = {
48    {	"efi", ALIAS_PTR2TYPE(&gpt_uuid_efi) },
49    {	NULL, 0 }
50};
51
52/* CRC32 code derived from work by Gary S. Brown. */
53static const uint32_t crc32_tab[] = {
54	0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f,
55	0xe963a535, 0x9e6495a3,	0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
56	0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, 0x1db71064, 0x6ab020f2,
57	0xf3b97148, 0x84be41de,	0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
58	0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec,	0x14015c4f, 0x63066cd9,
59	0xfa0f3d63, 0x8d080df5,	0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172,
60	0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b,	0x35b5a8fa, 0x42b2986c,
61	0xdbbbc9d6, 0xacbcf940,	0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
62	0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423,
63	0xcfba9599, 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
64	0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d,	0x76dc4190, 0x01db7106,
65	0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
66	0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d,
67	0x91646c97, 0xe6635c01, 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e,
68	0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950,
69	0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
70	0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7,
71	0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0,
72	0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa,
73	0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
74	0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81,
75	0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a,
76	0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, 0xe3630b12, 0x94643b84,
77	0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
78	0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb,
79	0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc,
80	0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 0xd6d6a3e8, 0xa1d1937e,
81	0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
82	0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55,
83	0x316e8eef, 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
84	0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, 0xb2bd0b28,
85	0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
86	0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f,
87	0x72076785, 0x05005713, 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38,
88	0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242,
89	0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
90	0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69,
91	0x616bffd3, 0x166ccf45, 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2,
92	0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc,
93	0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
94	0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693,
95	0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
96	0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d
97};
98
99static uint32_t
100crc32(const void *buf, size_t sz)
101{
102	const uint8_t *p = (const uint8_t *)buf;
103	uint32_t crc = ~0U;
104
105	while (sz--)
106		crc = crc32_tab[(crc ^ *p++) & 0xff] ^ (crc >> 8);
107	return (crc ^ ~0U);
108}
109
110static u_int
111gpt_tblsz(u_int parts, u_int secsz)
112{
113	u_int ents;
114
115	ents = secsz / sizeof(struct gpt_ent);
116	return ((parts + ents - 1) / ents);
117}
118
119static u_int
120gpt_metadata(u_int where, u_int parts, u_int secsz)
121{
122	u_int secs;
123
124	if (where != SCHEME_META_IMG_START && where != SCHEME_META_IMG_END)
125		return (0);
126
127	secs = gpt_tblsz(parts, secsz);
128	secs += (where == SCHEME_META_IMG_START) ? 2 : 1;
129	return (secs);
130}
131
132static int
133gpt_filewrite(int fd, off_t ofs, void *buf, ssize_t bufsz)
134{
135
136	if (lseek(fd, ofs, SEEK_SET) != ofs)
137		return (errno);
138	if (write(fd, buf, bufsz) != bufsz)
139		return (errno);
140	return (0);
141}
142
143static int
144gpt_write_pmbr(int fd, off_t nblocks, u_int secsz)
145{
146	u_char *pmbr;
147	uint32_t secs;
148	int error;
149
150	secs = (nblocks > UINT32_MAX) ? UINT32_MAX : nblocks;
151
152	pmbr = malloc(secsz);
153	if (pmbr == NULL)
154		return (errno);
155	memset(pmbr, 0, secsz);
156	pmbr[DOSPARTOFF + 2] = 2;
157	pmbr[DOSPARTOFF + 4] = 0xee;
158	pmbr[DOSPARTOFF + 5] = 0xff;
159	pmbr[DOSPARTOFF + 6] = 0xff;
160	pmbr[DOSPARTOFF + 7] = 0xff;
161	le32enc(pmbr + DOSPARTOFF + 8, 1);
162	le32enc(pmbr + DOSPARTOFF + 12, secs);
163	le16enc(pmbr + DOSMAGICOFFSET, DOSMAGIC);
164	error = gpt_filewrite(fd, 0, pmbr, secsz);
165	free(pmbr);
166	return (error);
167}
168
169static struct gpt_ent *
170gpt_mktbl(u_int tblsz, u_int secsz)
171{
172	uuid_t uuid;
173	struct gpt_ent *tbl, *ent;
174	struct part *part;
175	uint64_t limit;
176	int c, idx;
177
178	tbl = calloc(tblsz, secsz);
179	if (tbl == NULL)
180		return (NULL);
181
182	STAILQ_FOREACH(part, &partlist, link) {
183		ent = tbl + part->index;
184		uuid_enc_le(&ent->ent_type, ALIAS_TYPE2PTR(part->type));
185		uuidgen(&uuid, 1);
186		uuid_enc_le(&ent->ent_uuid, &uuid);
187		le64enc(&ent->ent_lba_start, part->offset / secsz);
188		limit = (part->offset + part->size) / secsz;
189		le64enc(&ent->ent_lba_end, limit - 1);
190		if (part->label != NULL) {
191			idx = 0;
192			while ((c = part->label[idx]) != '\0') {
193				le16enc(ent->ent_name + idx, c);
194				idx++;
195			}
196		}
197	}
198	return (tbl);
199}
200
201static int
202gpt_write_hdr(int fd, struct gpt_hdr *hdr, uint64_t self, uint64_t alt,
203    uint64_t tbl, u_int secsz)
204{
205	uint32_t crc;
206
207	le64enc(&hdr->hdr_lba_self, self);
208	le64enc(&hdr->hdr_lba_alt, alt);
209	le64enc(&hdr->hdr_lba_table, tbl);
210	hdr->hdr_crc_self = 0;
211	crc = crc32(hdr, offsetof(struct gpt_hdr, padding));
212	le64enc(&hdr->hdr_crc_self, crc);
213	return (gpt_filewrite(fd, self * secsz, hdr, secsz));
214}
215
216static int
217gpt_write(int fd, off_t imgsz, u_int parts, u_int secsz)
218{
219	uuid_t uuid;
220	struct gpt_ent *tbl;
221	struct gpt_hdr *hdr;
222	off_t nblocks;
223	uint32_t crc;
224	u_int tblsz;
225	int error;
226
227	nblocks = imgsz / secsz;
228
229	/* PMBR */
230	error = gpt_write_pmbr(fd, nblocks, secsz);
231	if (error)
232		return (error);
233
234	/* GPT table(s) */
235	tblsz = gpt_tblsz(parts, secsz);
236	tbl = gpt_mktbl(tblsz, secsz);
237	if (tbl == NULL)
238		return (errno);
239	error = gpt_filewrite(fd, 2 * secsz, tbl, tblsz * secsz);
240	if (error)
241		goto out;
242	error = gpt_filewrite(fd, imgsz - (tblsz + 1) * secsz, tbl,
243	    tblsz * secsz);
244	if (error)
245		goto out;
246
247	/* GPT header(s) */
248	hdr = malloc(secsz);
249	if (hdr == NULL) {
250		error = errno;
251		goto out;
252	}
253	memset(hdr, 0, secsz);
254	memcpy(hdr->hdr_sig, GPT_HDR_SIG, sizeof(hdr->hdr_sig));
255	le32enc(&hdr->hdr_revision, GPT_HDR_REVISION);
256	le32enc(&hdr->hdr_size, offsetof(struct gpt_hdr, padding));
257	le64enc(&hdr->hdr_lba_start, 2 + tblsz);
258	le64enc(&hdr->hdr_lba_end, nblocks - tblsz - 2);
259	uuidgen(&uuid, 1);
260	uuid_enc_le(&hdr->hdr_uuid, &uuid);
261	le32enc(&hdr->hdr_entries, parts);
262	le32enc(&hdr->hdr_entsz, sizeof(struct gpt_ent));
263	crc = crc32(tbl, parts * sizeof(struct gpt_ent));
264	le32enc(&hdr->hdr_crc_table, crc);
265	error = gpt_write_hdr(fd, hdr, 1, nblocks - 1, 2, secsz);
266	if (!error)
267		error = gpt_write_hdr(fd, hdr, nblocks - 1, 1,
268		    nblocks - tblsz - 1, secsz);
269	free(hdr);
270
271 out:
272	free(tbl);
273	return (error);
274}
275
276static struct mkimg_scheme gpt_scheme = {
277	.name = "gpt",
278	.description = "GUID Partition Table",
279	.aliases = gpt_aliases,
280	.metadata = gpt_metadata,
281	.write = gpt_write,
282	.nparts = 4096,
283	.labellen = 36
284};
285
286SCHEME_DEFINE(gpt_scheme);
287