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/recover.c,v 1.8 2005/08/31 01:47:19 marcel Exp $");
34 #endif
35 #ifdef __RCSID
36 __RCSID("$NetBSD: recover.c,v 1.19 2020/12/13 21:55:25 jnemeth Exp $");
37 #endif
38
39 #include <sys/types.h>
40
41 #include <err.h>
42 #include <stddef.h>
43 #include <stdio.h>
44 #include <stdlib.h>
45 #include <string.h>
46 #include <unistd.h>
47
48 #include "map.h"
49 #include "gpt.h"
50 #include "gpt_private.h"
51
52 static int cmd_recover(gpt_t, int, char *[]);
53
54 static const char *recoverhelp[] = {
55 "",
56 };
57
58 struct gpt_cmd c_recover = {
59 "recover",
60 cmd_recover,
61 recoverhelp, __arraycount(recoverhelp),
62 GPT_SYNC,
63 };
64
65 #define usage() gpt_usage(NULL, &c_recover)
66
67 static int
recover_gpt_hdr(gpt_t gpt,int type,off_t last)68 recover_gpt_hdr(gpt_t gpt, int type, off_t last)
69 {
70 const char *name, *origname;
71 map_t *dgpt, dtbl, sgpt, stbl __unused;
72 struct gpt_hdr *hdr;
73
74 if (gpt_add_hdr(gpt, type, last) == -1)
75 return -1;
76
77 switch (type) {
78 case MAP_TYPE_PRI_GPT_HDR:
79 dgpt = &gpt->gpt;
80 dtbl = gpt->tbl;
81 sgpt = gpt->tpg;
82 stbl = gpt->lbt;
83 origname = "secondary";
84 name = "primary";
85 break;
86 case MAP_TYPE_SEC_GPT_HDR:
87 dgpt = &gpt->tpg;
88 dtbl = gpt->lbt;
89 sgpt = gpt->gpt;
90 stbl = gpt->tbl;
91 origname = "primary";
92 name = "secondary";
93 break;
94 default:
95 gpt_warn(gpt, "Bad table type %d", type);
96 return -1;
97 }
98
99 memcpy((*dgpt)->map_data, sgpt->map_data, gpt->secsz);
100 hdr = (*dgpt)->map_data;
101 hdr->hdr_lba_self = htole64((uint64_t)(*dgpt)->map_start);
102 hdr->hdr_lba_alt = htole64((uint64_t)sgpt->map_start);
103 hdr->hdr_lba_table = htole64((uint64_t)dtbl->map_start);
104 hdr->hdr_crc_self = 0;
105 hdr->hdr_crc_self = htole32(crc32(hdr, le32toh(hdr->hdr_size)));
106 if (gpt_write(gpt, *dgpt) == -1) {
107 gpt_warnx(gpt, "Writing %s GPT header failed", name);
108 return -1;
109 }
110 gpt_msg(gpt, "Recovered %s GPT header from %s", name, origname);
111 return 0;
112 }
113
114 static int
recover_gpt_tbl(gpt_t gpt,int type,off_t start)115 recover_gpt_tbl(gpt_t gpt, int type, off_t start)
116 {
117 const char *name, *origname;
118 map_t *dtbl, stbl;
119
120 switch (type) {
121 case MAP_TYPE_PRI_GPT_TBL:
122 dtbl = &gpt->tbl;
123 stbl = gpt->lbt;
124 origname = "secondary";
125 name = "primary";
126 break;
127 case MAP_TYPE_SEC_GPT_TBL:
128 dtbl = &gpt->lbt;
129 stbl = gpt->tbl;
130 origname = "primary";
131 name = "secondary";
132 break;
133 default:
134 gpt_warn(gpt, "Bad table type %d", type);
135 return -1;
136 }
137
138 *dtbl = map_add(gpt, start, stbl->map_size, type, stbl->map_data, 0);
139 if (*dtbl == NULL) {
140 gpt_warnx(gpt, "Adding %s GPT table failed", name);
141 return -1;
142 }
143 if (gpt_write(gpt, *dtbl) == -1) {
144 gpt_warnx(gpt, "Writing %s GPT table failed", name);
145 return -1;
146 }
147 gpt_msg(gpt, "Recovered %s GPT table from %s", name, origname);
148 return 0;
149 }
150
151 static int
recover(gpt_t gpt)152 recover(gpt_t gpt)
153 {
154 off_t last = gpt_last(gpt);
155 map_t map;
156 struct mbr *mbr;
157
158 if (map_find(gpt, MAP_TYPE_MBR) != NULL) {
159 gpt_warnx(gpt, "Device contains an MBR");
160 return -1;
161 }
162
163 gpt->gpt = map_find(gpt, MAP_TYPE_PRI_GPT_HDR);
164 gpt->tpg = map_find(gpt, MAP_TYPE_SEC_GPT_HDR);
165 gpt->tbl = map_find(gpt, MAP_TYPE_PRI_GPT_TBL);
166 gpt->lbt = map_find(gpt, MAP_TYPE_SEC_GPT_TBL);
167
168 if (gpt->gpt == NULL && gpt->tpg == NULL) {
169 gpt_warnx(gpt, "No primary or secondary GPT headers, "
170 "can't recover");
171 return -1;
172 }
173 if (gpt->tbl == NULL && gpt->lbt == NULL) {
174 gpt_warnx(gpt, "No primary or secondary GPT tables, "
175 "can't recover");
176 return -1;
177 }
178
179 if (gpt->gpt != NULL &&
180 le64toh(((struct gpt_hdr *)(gpt->gpt->map_data))->hdr_lba_alt) !=
181 (uint64_t)last) {
182 gpt_warnx(gpt, "Media size has changed, please use "
183 "'%s resizedisk'", getprogname());
184 return -1;
185 }
186
187 if (gpt->tbl != NULL && gpt->lbt == NULL) {
188 if (recover_gpt_tbl(gpt, MAP_TYPE_SEC_GPT_TBL,
189 last - gpt->tbl->map_size) == -1)
190 return -1;
191 } else if (gpt->tbl == NULL && gpt->lbt != NULL) {
192 if (recover_gpt_tbl(gpt, MAP_TYPE_PRI_GPT_TBL, 2LL) == -1)
193 return -1;
194 }
195
196 if (gpt->gpt != NULL && gpt->tpg == NULL) {
197 if (recover_gpt_hdr(gpt, MAP_TYPE_SEC_GPT_HDR, last) == -1)
198 return -1;
199 } else if (gpt->gpt == NULL && gpt->tpg != NULL) {
200 if (recover_gpt_hdr(gpt, MAP_TYPE_PRI_GPT_HDR, 1LL) == -1)
201 return -1;
202 }
203
204 /*
205 * Create PMBR if it doesn't already exist.
206 */
207 if (map_find(gpt, MAP_TYPE_PMBR) == NULL) {
208 if (map_free(gpt, 0LL, 1LL) == 0) {
209 gpt_warnx(gpt, "No room for the PMBR");
210 return -1;
211 }
212 mbr = gpt_read(gpt, 0LL, 1);
213 if (mbr == NULL) {
214 gpt_warnx(gpt, "Error reading MBR");
215 return -1;
216 }
217 memset(mbr, 0, sizeof(*mbr));
218 mbr->mbr_sig = htole16(MBR_SIG);
219 gpt_create_pmbr_part(mbr->mbr_part, last, 0);
220
221 map = map_add(gpt, 0LL, 1LL, MAP_TYPE_PMBR, mbr, 1);
222 if (gpt_write(gpt, map) == -1) {
223 gpt_warn(gpt, "Can't write PMBR");
224 return -1;
225 }
226 gpt_msg(gpt,
227 "Recreated PMBR (you may need to rerun 'gpt biosboot'");
228 }
229 return 0;
230 }
231
232 static int
cmd_recover(gpt_t gpt,int argc,char * argv[])233 cmd_recover(gpt_t gpt, int argc, char *argv[])
234 {
235 int ch;
236
237 while ((ch = getopt(argc, argv, "r")) != -1) {
238 switch(ch) {
239 default:
240 return usage();
241 }
242 }
243
244 if (argc != optind)
245 return usage();
246
247 return recover(gpt);
248 }
249