xref: /netbsd-src/sbin/gpt/restore.c (revision d147ce22261127af83eeb5ca2822a025e97f785b)
1 /*-
2  * Copyright (c) 2002 Marcel Moolenaar
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  *
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 
27 #if HAVE_NBTOOL_CONFIG_H
28 #include "nbtool_config.h"
29 #endif
30 
31 #include <sys/cdefs.h>
32 #ifdef __FBSDID
33 __FBSDID("$FreeBSD: src/sbin/gpt/create.c,v 1.11 2005/08/31 01:47:19 marcel Exp $");
34 #endif
35 #ifdef __RCSID
36 __RCSID("$NetBSD: restore.c,v 1.20 2020/06/07 05:42:25 thorpej Exp $");
37 #endif
38 
39 #include <sys/types.h>
40 #include <sys/bootblock.h>
41 #include <sys/disklabel_gpt.h>
42 
43 #include <err.h>
44 #include <stddef.h>
45 #include <stdio.h>
46 #include <stdlib.h>
47 #include <string.h>
48 #include <unistd.h>
49 #include <prop/proplib.h>
50 
51 #include "map.h"
52 #include "gpt.h"
53 #include "gpt_private.h"
54 
55 static int cmd_restore(gpt_t, int, char *[]);
56 
57 static const char *restorehelp[] = {
58 	"[-F] [-i infile]",
59 };
60 
61 struct gpt_cmd c_restore = {
62 	"restore",
63 	cmd_restore,
64 	restorehelp, __arraycount(restorehelp),
65 	GPT_SYNC,
66 };
67 
68 #define usage() gpt_usage(NULL, &c_restore)
69 
70 #define PROP_ERR(x)     if (!(x)) {		\
71 	gpt_warnx(gpt, "proplib failure");	\
72 	return -1;				\
73 }
74 
75 static int
restore_mbr(gpt_t gpt,struct mbr * mbr,prop_dictionary_t mbr_dict,off_t last)76 restore_mbr(gpt_t gpt, struct mbr *mbr, prop_dictionary_t mbr_dict, off_t last)
77 {
78 	unsigned int i;
79 	struct mbr_part *part;
80 
81 	PROP_ERR(prop_dictionary_get_uint(mbr_dict, "index", &i));
82 	part = &mbr->mbr_part[i];
83 
84 	PROP_ERR(prop_dictionary_get_uint8(mbr_dict, "flag", &part->part_flag));
85 	PROP_ERR(prop_dictionary_get_uint8(mbr_dict, "start_head",
86 					   &part->part_shd));
87 	PROP_ERR(prop_dictionary_get_uint8(mbr_dict, "start_sector",
88 					   &part->part_ssect ));
89 	PROP_ERR(prop_dictionary_get_uint8(mbr_dict, "start_cylinder",
90 					   &part->part_scyl));
91 	PROP_ERR(prop_dictionary_get_uint8(mbr_dict, "type",
92 					   &part->part_typ));
93 	PROP_ERR(prop_dictionary_get_uint8(mbr_dict, "end_head",
94 					   &part->part_ehd));
95 	PROP_ERR(prop_dictionary_get_uint8(mbr_dict, "end_sector",
96 					   &part->part_esect));
97 	PROP_ERR(prop_dictionary_get_uint8(mbr_dict, "end_cylinder",
98 					   &part->part_ecyl));
99 	PROP_ERR(prop_dictionary_get_uint16(mbr_dict, "lba_start_low",
100 					    &part->part_start_lo));
101 	part->part_start_lo = htole16(part->part_start_lo);
102 	PROP_ERR(prop_dictionary_get_uint16(mbr_dict, "lba_start_high",
103 					    &part->part_start_hi));
104 	part->part_start_hi = htole16(part->part_start_hi);
105 
106 	/* adjust PMBR size to size of device */
107 	if (part->part_typ == MBR_PTYPE_PMBR) {
108 		if (last > 0xffffffff) {
109 			mbr->mbr_part[0].part_size_lo = htole16(0xffff);
110 			mbr->mbr_part[0].part_size_hi = htole16(0xffff);
111 		} else {
112 			mbr->mbr_part[0].part_size_lo = htole16((uint16_t)last);
113 			mbr->mbr_part[0].part_size_hi = htole16(
114 			    (uint16_t)(last >> 16));
115 		}
116 	} else {
117 		PROP_ERR(prop_dictionary_get_uint16(mbr_dict, "lba_size_low",
118 						    &part->part_size_lo));
119 		part->part_size_lo = htole16(part->part_size_lo);
120 		PROP_ERR(prop_dictionary_get_uint16(mbr_dict, "lba_size_high",
121 						    &part->part_size_hi));
122 		part->part_size_hi = htole16(part->part_size_hi);
123 	}
124 	return 0;
125 }
126 
127 static int
restore_ent(gpt_t gpt,prop_dictionary_t gpt_dict,void * secbuf,u_int gpt_size,u_int entries)128 restore_ent(gpt_t gpt, prop_dictionary_t gpt_dict, void *secbuf, u_int gpt_size,
129     u_int entries)
130 {
131 	unsigned int i;
132 	struct gpt_ent ent;
133 	const char *s;
134 
135 	memset(&ent, 0, sizeof(ent));
136 	PROP_ERR(prop_dictionary_get_string(gpt_dict, "type", &s));
137 	if (gpt_uuid_parse(s, ent.ent_type) != 0) {
138 		gpt_warnx(gpt, "%s: not able to convert to an UUID", s);
139 		return -1;
140 	}
141 	PROP_ERR(prop_dictionary_get_string(gpt_dict, "guid", &s));
142 	if (gpt_uuid_parse(s, ent.ent_guid) != 0) {
143 		gpt_warnx(gpt, "%s: not able to convert to an UUID", s);
144 		return -1;
145 	}
146 	PROP_ERR(prop_dictionary_get_uint64(gpt_dict, "start",
147 					    &ent.ent_lba_start));
148 	ent.ent_lba_start = htole64(ent.ent_lba_start);
149 	PROP_ERR(prop_dictionary_get_uint64(gpt_dict, "end",
150 					    &ent.ent_lba_end));
151 	ent.ent_lba_end = htole64(ent.ent_lba_end);
152 	PROP_ERR(prop_dictionary_get_uint64(gpt_dict, "attributes",
153 					    &ent.ent_attr));
154 	ent.ent_attr = htole64(ent.ent_attr);
155 
156 	if (prop_dictionary_get_string(gpt_dict, "name", &s)) {
157 		utf8_to_utf16((const uint8_t *)s, ent.ent_name,
158 		    __arraycount(ent.ent_name));
159 	}
160 	PROP_ERR(prop_dictionary_get_uint(gpt_dict, "index", &i));
161 	if (i > entries) {
162 		gpt_warnx(gpt, "Entity index out of bounds %u > %u\n",
163 		    i, entries);
164 		return -1;
165 	}
166 	memcpy((char *)secbuf + gpt->secsz + ((i - 1) * sizeof(ent)),
167 	    &ent, sizeof(ent));
168 	return 0;
169 }
170 
171 static int
restore(gpt_t gpt,const char * infile,int force)172 restore(gpt_t gpt, const char *infile, int force)
173 {
174 	gpt_uuid_t gpt_guid, uuid;
175 	off_t firstdata, last, lastdata, gpe_start, gpe_end;
176 	map_t map;
177 	struct mbr *mbr;
178 	struct gpt_hdr *hdr;
179 	unsigned int i, gpt_size;
180 	prop_dictionary_t props, gpt_dict, mbr_dict, type_dict;
181 	prop_object_iterator_t propiter;
182 	prop_data_t propdata;
183 	prop_array_t mbr_array, gpt_array;
184 	prop_number_t propnum;
185 	unsigned int entries;
186 	const char *s;
187 	void *secbuf = NULL;
188 	int rv = -1;
189 
190 	last = gpt->mediasz / gpt->secsz - 1LL;
191 
192 	if (map_find(gpt, MAP_TYPE_PRI_GPT_HDR) != NULL ||
193 	    map_find(gpt, MAP_TYPE_SEC_GPT_HDR) != NULL) {
194 		if (!force) {
195 			gpt_warnx(gpt, "Device contains a GPT");
196 			return -1;
197 		}
198 	}
199 	map = map_find(gpt, MAP_TYPE_MBR);
200 	if (map != NULL) {
201 		if (!force) {
202 			gpt_warnx(gpt, "Device contains an MBR");
203 			return -1;
204 		}
205 		/* Nuke the MBR in our internal map. */
206 		map->map_type = MAP_TYPE_UNUSED;
207 	}
208 
209 	props = prop_dictionary_internalize_from_file(
210 	    strcmp(infile, "-") == 0 ? "/dev/stdin" : infile);
211 	if (props == NULL) {
212 		gpt_warnx(gpt, "Unable to read/parse backup file");
213 		return -1;
214 	}
215 
216 	propnum = prop_dictionary_get(props, "sector_size");
217 	PROP_ERR(propnum);
218 	if (!prop_number_equals_signed(propnum, gpt->secsz)) {
219 		gpt_warnx(gpt, "Sector size does not match backup");
220 		prop_object_release(props);
221 		return -1;
222 	}
223 
224 	gpt_dict = prop_dictionary_get(props, "GPT_HDR");
225 	PROP_ERR(gpt_dict);
226 
227 	propnum = prop_dictionary_get(gpt_dict, "revision");
228 	PROP_ERR(propnum);
229 	if (!prop_number_equals_unsigned(propnum, 0x10000)) {
230 		gpt_warnx(gpt, "backup is not revision 1.0");
231 		prop_object_release(gpt_dict);
232 		prop_object_release(props);
233 		return -1;
234 	}
235 
236 	PROP_ERR(prop_dictionary_get_uint(gpt_dict, "entries", &entries));
237 
238 	gpt_size = (u_int)(entries * sizeof(struct gpt_ent) / gpt->secsz);
239 	if (gpt_size * sizeof(struct gpt_ent) % gpt->secsz)
240 		gpt_size++;
241 
242 	PROP_ERR(prop_dictionary_get_string(gpt_dict, "guid", &s));
243 	if (gpt_uuid_parse(s, gpt_guid) != 0) {
244 		gpt_warnx(gpt, "%s: not able to convert to an UUID", s);
245 		goto out;
246 	}
247 	firstdata = gpt_size + 2;		/* PMBR and GPT header */
248 	lastdata = last - gpt_size - 1;		/* alt. GPT table and header */
249 
250 	type_dict = prop_dictionary_get(props, "GPT_TBL");
251 	PROP_ERR(type_dict);
252 	gpt_array = prop_dictionary_get(type_dict, "gpt_array");
253 	PROP_ERR(gpt_array);
254 	propiter = prop_array_iterator(gpt_array);
255 	PROP_ERR(propiter);
256 	while ((gpt_dict = prop_object_iterator_next(propiter)) != NULL) {
257 		PROP_ERR(prop_dictionary_get_string(gpt_dict, "type", &s));
258 		if (gpt_uuid_parse(s, uuid) != 0) {
259 			gpt_warnx(gpt, "%s: not able to convert to an UUID", s);
260 			goto out;
261 		}
262 		if (gpt_uuid_is_nil(uuid))
263 			continue;
264 		PROP_ERR(prop_dictionary_get_int64(gpt_dict, "start",
265 						   &gpe_start));
266 		PROP_ERR(prop_dictionary_get_int64(gpt_dict, "end",
267 						   &gpe_end));
268 		if (gpe_start < firstdata || gpe_end > lastdata) {
269 			gpt_warnx(gpt, "Backup GPT doesn't fit");
270 			goto out;
271 		}
272 	}
273 	prop_object_iterator_release(propiter);
274 
275 	/* GPT TABLE + GPT HEADER */
276 	if ((secbuf = calloc(gpt_size + 1, gpt->secsz)) == NULL) {
277 		gpt_warn(gpt, "not enough memory to create a sector buffer");
278 		goto out;
279 	}
280 
281 	if (lseek(gpt->fd, 0LL, SEEK_SET) == -1) {
282 		gpt_warn(gpt, "Can't seek to beginning");
283 		goto out;
284 	}
285 	for (i = 0; i < firstdata; i++) {
286 		if (write(gpt->fd, secbuf, gpt->secsz) != (ssize_t)gpt->secsz) {
287 			gpt_warn(gpt, "Error writing");
288 			goto out;
289 		}
290 	}
291 	if (lseek(gpt->fd, (lastdata + 1) * gpt->secsz, SEEK_SET) == -1) {
292 		gpt_warn(gpt, "Can't seek to end");
293 		goto out;
294 	}
295 	for (i = (u_int)(lastdata + 1); i <= (u_int)last; i++) {
296 		if (write(gpt->fd, secbuf, gpt->secsz) != (ssize_t)gpt->secsz) {
297 			gpt_warn(gpt, "Error writing");
298 			goto out;
299 		}
300 	}
301 
302 	mbr = secbuf;
303 	type_dict = prop_dictionary_get(props, "MBR");
304 	PROP_ERR(type_dict);
305 	propdata = prop_dictionary_get(type_dict, "code");
306 	PROP_ERR(propdata);
307 	memcpy(mbr->mbr_code, prop_data_value(propdata),
308 	    sizeof(mbr->mbr_code));
309 	mbr_array = prop_dictionary_get(type_dict, "mbr_array");
310 	PROP_ERR(mbr_array);
311 	propiter = prop_array_iterator(mbr_array);
312 	PROP_ERR(propiter);
313 	while ((mbr_dict = prop_object_iterator_next(propiter)) != NULL) {
314 		if (restore_mbr(gpt, mbr, mbr_dict, last) == -1)
315 			goto out;
316 	}
317 
318 	prop_object_iterator_release(propiter);
319 	mbr->mbr_sig = htole16(MBR_SIG);
320 	if (lseek(gpt->fd, 0LL, SEEK_SET) == -1 ||
321 	    write(gpt->fd, mbr, gpt->secsz) != (ssize_t)gpt->secsz) {
322 		gpt_warn(gpt, "Unable to seek/write MBR");
323 		return -1;
324 	}
325 
326 	propiter = prop_array_iterator(gpt_array);
327 	PROP_ERR(propiter);
328 
329 	while ((gpt_dict = prop_object_iterator_next(propiter)) != NULL) {
330 		if (restore_ent(gpt, gpt_dict, secbuf, gpt_size, entries) == -1)
331 			goto out;
332 	}
333 	prop_object_iterator_release(propiter);
334 
335 	size_t len = gpt_size * gpt->secsz;
336 	if (lseek(gpt->fd, 2 * gpt->secsz, SEEK_SET) == -1 ||
337 	    write(gpt->fd, (char *)secbuf + gpt->secsz, len) != (ssize_t) len) {
338 		gpt_warn(gpt, "Unable to write primary GPT");
339 		goto out;
340 	}
341 
342 	if (lseek(gpt->fd, (lastdata + 1) * gpt->secsz, SEEK_SET) == -1 ||
343 	    write(gpt->fd, (char *)secbuf + gpt->secsz, len) != (ssize_t) len) {
344 		gpt_warn(gpt, "Unable to write secondary GPT");
345 		goto out;
346 	}
347 
348 	memset(secbuf, 0, gpt->secsz);
349 	hdr = secbuf;
350 	memcpy(hdr->hdr_sig, GPT_HDR_SIG, sizeof(hdr->hdr_sig));
351 	hdr->hdr_revision = htole32(GPT_HDR_REVISION);
352 	hdr->hdr_size = htole32(GPT_HDR_SIZE);
353 	hdr->hdr_lba_self = htole64(GPT_HDR_BLKNO);
354 	hdr->hdr_lba_alt = htole64((uint64_t)last);
355 	hdr->hdr_lba_start = htole64((uint64_t)firstdata);
356 	hdr->hdr_lba_end = htole64((uint64_t)lastdata);
357 	gpt_uuid_copy(hdr->hdr_guid, gpt_guid);
358 	hdr->hdr_lba_table = htole64(2);
359 	hdr->hdr_entries = htole32(entries);
360 	hdr->hdr_entsz = htole32(sizeof(struct gpt_ent));
361 	hdr->hdr_crc_table = htole32(crc32((char *)secbuf + gpt->secsz, len));
362 	hdr->hdr_crc_self = htole32(crc32(hdr, GPT_HDR_SIZE));
363 	if (lseek(gpt->fd, gpt->secsz, SEEK_SET) == -1 ||
364 	    write(gpt->fd, hdr, gpt->secsz) != (ssize_t)gpt->secsz) {
365 		gpt_warn(gpt, "Unable to write primary header");
366 		goto out;
367 	}
368 
369 	hdr->hdr_lba_self = htole64((uint64_t)last);
370 	hdr->hdr_lba_alt = htole64(GPT_HDR_BLKNO);
371 	hdr->hdr_lba_table = htole64((uint64_t)(lastdata + 1));
372 	hdr->hdr_crc_self = 0;
373 	hdr->hdr_crc_self = htole32(crc32(hdr, GPT_HDR_SIZE));
374 	if (lseek(gpt->fd, last * gpt->secsz, SEEK_SET) == -1 ||
375 	    write(gpt->fd, hdr, gpt->secsz) != (ssize_t)gpt->secsz) {
376 		gpt_warn(gpt, "Unable to write secondary header");
377 		goto out;
378 	}
379 	rv = 0;
380 
381 out:
382 	free(secbuf);
383 	prop_object_release(props);
384 	return rv;
385 }
386 
387 static int
cmd_restore(gpt_t gpt,int argc,char * argv[])388 cmd_restore(gpt_t gpt, int argc, char *argv[])
389 {
390 	int ch;
391 	int force = 0;
392 	const char *infile = "-";
393 
394 	while ((ch = getopt(argc, argv, "Fi:")) != -1) {
395 		switch(ch) {
396 		case 'i':
397 			infile = optarg;
398 			break;
399 		case 'F':
400 			force = 1;
401 			break;
402 		default:
403 			return usage();
404 		}
405 	}
406 
407 	if (argc != optind)
408 		return usage();
409 
410 	return restore(gpt, infile, force);
411 }
412