xref: /netbsd-src/sys/dev/dkwedge/dkwedge_gpt.c (revision 89c40d7e6d8331b8b56615fed77be1b42a5efc4d)
1 /*	$NetBSD: dkwedge_gpt.c,v 1.26 2020/04/11 16:00:34 jdolecek Exp $	*/
2 
3 /*-
4  * Copyright (c) 2004 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Jason R. Thorpe.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  * EFI GUID Partition Table support for disk wedges
34  */
35 
36 #include <sys/cdefs.h>
37 __KERNEL_RCSID(0, "$NetBSD: dkwedge_gpt.c,v 1.26 2020/04/11 16:00:34 jdolecek Exp $");
38 
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/proc.h>
42 #include <sys/errno.h>
43 #include <sys/disk.h>
44 #include <sys/vnode.h>
45 #include <sys/buf.h>
46 
47 #include <sys/disklabel_gpt.h>
48 #include <sys/uuid.h>
49 
50 /* UTF-8 encoding stuff */
51 #include <fs/unicode.h>
52 
53 /*
54  * GUID to dkw_ptype mapping information.
55  *
56  * GPT_ENT_TYPE_MS_BASIC_DATA is not suited to mapping.  Aside from being
57  * used for multiple Microsoft file systems, Linux uses it for its own
58  * set of native file systems.  Treating this GUID as unknown seems best.
59  */
60 
61 static const struct {
62 	struct uuid ptype_guid;
63 	const char *ptype_str;
64 } gpt_ptype_guid_to_str_tab[] = {
65 	{ GPT_ENT_TYPE_EFI,			DKW_PTYPE_FAT },
66 	{ GPT_ENT_TYPE_NETBSD_SWAP,		DKW_PTYPE_SWAP },
67 	{ GPT_ENT_TYPE_FREEBSD_SWAP,		DKW_PTYPE_SWAP },
68 	{ GPT_ENT_TYPE_NETBSD_FFS,		DKW_PTYPE_FFS },
69 	{ GPT_ENT_TYPE_FREEBSD_UFS,		DKW_PTYPE_FFS },
70 	{ GPT_ENT_TYPE_APPLE_UFS,		DKW_PTYPE_FFS },
71 	{ GPT_ENT_TYPE_NETBSD_LFS,		DKW_PTYPE_LFS },
72 	{ GPT_ENT_TYPE_NETBSD_RAIDFRAME,	DKW_PTYPE_RAIDFRAME },
73 	{ GPT_ENT_TYPE_NETBSD_CCD,		DKW_PTYPE_CCD },
74 	{ GPT_ENT_TYPE_NETBSD_CGD,		DKW_PTYPE_CGD },
75 	{ GPT_ENT_TYPE_APPLE_HFS,		DKW_PTYPE_APPLEHFS },
76 	{ GPT_ENT_TYPE_VMWARE_VMKCORE,		DKW_PTYPE_VMKCORE },
77 	{ GPT_ENT_TYPE_VMWARE_VMFS,		DKW_PTYPE_VMFS },
78 	{ GPT_ENT_TYPE_VMWARE_RESERVED,		DKW_PTYPE_VMWRESV },
79 	{ GPT_ENT_TYPE_MS_BASIC_DATA,		DKW_PTYPE_NTFS },
80 	{ GPT_ENT_TYPE_LINUX_DATA,		DKW_PTYPE_EXT2FS },
81 	{ GPT_ENT_TYPE_FREEBSD_ZFS,		DKW_PTYPE_ZFS },
82 };
83 
84 static const char *
gpt_ptype_guid_to_str(const struct uuid * guid)85 gpt_ptype_guid_to_str(const struct uuid *guid)
86 {
87 	int i;
88 
89 	for (i = 0; i < __arraycount(gpt_ptype_guid_to_str_tab); i++) {
90 		if (memcmp(&gpt_ptype_guid_to_str_tab[i].ptype_guid,
91 			   guid, sizeof(*guid)) == 0)
92 			return (gpt_ptype_guid_to_str_tab[i].ptype_str);
93 	}
94 
95 	return (DKW_PTYPE_UNKNOWN);
96 }
97 
98 static int
gpt_verify_header_crc(struct gpt_hdr * hdr)99 gpt_verify_header_crc(struct gpt_hdr *hdr)
100 {
101 	uint32_t crc;
102 	int rv;
103 
104 	crc = hdr->hdr_crc_self;
105 	hdr->hdr_crc_self = 0;
106 	rv = le32toh(crc) == crc32(0, (void *)hdr, le32toh(hdr->hdr_size));
107 	hdr->hdr_crc_self = crc;
108 
109 	return (rv);
110 }
111 
112 static int
dkwedge_discover_gpt(struct disk * pdk,struct vnode * vp)113 dkwedge_discover_gpt(struct disk *pdk, struct vnode *vp)
114 {
115 	static const struct uuid ent_type_unused = GPT_ENT_TYPE_UNUSED;
116 	static const char gpt_hdr_sig[] = GPT_HDR_SIG;
117 	struct dkwedge_info dkw;
118 	struct buf *bp;
119 	uint32_t secsize;
120 	struct gpt_hdr *hdr;
121 	struct gpt_ent *ent;
122 	uint32_t entries, entsz;
123 	daddr_t lba_start, lba_end, lba_table;
124 	uint32_t gpe_crc;
125 	int error;
126 	u_int i;
127 	size_t r, n, sz;
128 	uint8_t *c;
129 
130 	secsize = DEV_BSIZE << pdk->dk_blkshift;
131 	bp = geteblk(secsize);
132 
133 	/*
134 	 * Note: We don't bother with a Legacy or Protective MBR
135 	 * here.  If a GPT is found, then the search stops, and
136 	 * the GPT is authoritative.
137 	 */
138 
139 	/* Read in the GPT Header. */
140 	error = dkwedge_read(pdk, vp, GPT_HDR_BLKNO << pdk->dk_blkshift,
141 	    bp->b_data, secsize);
142 	if (error)
143 		goto out;
144 	hdr = bp->b_data;
145 
146 	/* Validate it. */
147 	if (memcmp(gpt_hdr_sig, hdr->hdr_sig, sizeof(hdr->hdr_sig)) != 0) {
148 		/* XXX Should check at end-of-disk. */
149 		error = ESRCH;
150 		goto out;
151 	}
152 	if (hdr->hdr_revision != htole32(GPT_HDR_REVISION)) {
153 		/* XXX Should check at end-of-disk. */
154 		error = ESRCH;
155 		goto out;
156 	}
157 	if (le32toh(hdr->hdr_size) > secsize) {
158 		/* XXX Should check at end-of-disk. */
159 		error = ESRCH;
160 		goto out;
161 	}
162 	if (gpt_verify_header_crc(hdr) == 0) {
163 		/* XXX Should check at end-of-disk. */
164 		error = ESRCH;
165 		goto out;
166 	}
167 
168 	/* XXX Now that we found it, should we validate the backup? */
169 
170 	{
171 		struct uuid disk_guid;
172 		char guid_str[UUID_STR_LEN];
173 		uuid_dec_le(hdr->hdr_guid, &disk_guid);
174 		uuid_snprintf(guid_str, sizeof(guid_str), &disk_guid);
175 		aprint_verbose("%s: GPT GUID: %s\n", pdk->dk_name, guid_str);
176 	}
177 
178 	entries = le32toh(hdr->hdr_entries);
179 	entsz = roundup(le32toh(hdr->hdr_entsz), 8);
180 	if (entsz != sizeof(struct gpt_ent)) {
181 		aprint_error("%s: bogus GPT entry size: %u\n",
182 		    pdk->dk_name, le32toh(hdr->hdr_entsz));
183 		error = EINVAL;
184 		goto out;
185 	}
186 	gpe_crc = le32toh(hdr->hdr_crc_table);
187 
188 	/* XXX Clamp entries at 512 for now. */
189 	if (entries > 512) {
190 		aprint_error("%s: WARNING: clamping number of GPT entries to "
191 		    "512 (was %u)\n", pdk->dk_name, entries);
192 		entries = 512;
193 	}
194 
195 	lba_start = le64toh(hdr->hdr_lba_start);
196 	lba_end = le64toh(hdr->hdr_lba_end);
197 	lba_table = le64toh(hdr->hdr_lba_table);
198 	if (lba_start < 0 || lba_end < 0 || lba_table < 0) {
199 		aprint_error("%s: GPT block numbers out of range\n",
200 		    pdk->dk_name);
201 		error = EINVAL;
202 		goto out;
203 	}
204 
205 	brelse(bp, 0);
206 
207 	sz = roundup(entries * entsz, secsize);
208 	bp = geteblk(sz);
209 	error = dkwedge_read(pdk, vp, lba_table << pdk->dk_blkshift,
210 	    bp->b_data, sz);
211 	if (error) {
212 		/* XXX Should check alternate location. */
213 		aprint_error("%s: unable to read GPT partition array, "
214 		    "error = %d\n", pdk->dk_name, error);
215 		goto out;
216 	}
217 
218 	if (crc32(0, bp->b_data, entries * entsz) != gpe_crc) {
219 		/* XXX Should check alternate location. */
220 		aprint_error("%s: bad GPT partition array CRC\n",
221 		    pdk->dk_name);
222 		error = EINVAL;
223 		goto out;
224 	}
225 
226 	/*
227 	 * Walk the partitions, adding a wedge for each type we know about.
228 	 */
229 	for (i = 0; i < entries; i++) {
230 		struct uuid ptype_guid, ent_guid;
231 		const char *ptype;
232 		int j;
233 		char ptype_guid_str[UUID_STR_LEN], ent_guid_str[UUID_STR_LEN];
234 
235 		ent = (struct gpt_ent *)((char *)bp->b_data + (i * entsz));
236 
237 		uuid_dec_le(ent->ent_type, &ptype_guid);
238 		if (memcmp(&ptype_guid, &ent_type_unused,
239 			   sizeof(ptype_guid)) == 0)
240 			continue;
241 
242 		uuid_dec_le(ent->ent_guid, &ent_guid);
243 
244 		uuid_snprintf(ptype_guid_str, sizeof(ptype_guid_str),
245 		    &ptype_guid);
246 		uuid_snprintf(ent_guid_str, sizeof(ent_guid_str),
247 		    &ent_guid);
248 
249 		memset(&dkw, 0, sizeof(dkw));
250 
251 		/* figure out the type */
252 		ptype = gpt_ptype_guid_to_str(&ptype_guid);
253 		strlcpy(dkw.dkw_ptype, ptype, sizeof(dkw.dkw_ptype));
254 
255 		strlcpy(dkw.dkw_parent, pdk->dk_name, sizeof(dkw.dkw_parent));
256 		dkw.dkw_offset = le64toh(ent->ent_lba_start);
257 		dkw.dkw_size = le64toh(ent->ent_lba_end) - dkw.dkw_offset + 1;
258 
259 		/* XXX Make sure it falls within the disk's data area. */
260 
261 		if (ent->ent_name[0] == 0x0000)
262 			strlcpy(dkw.dkw_wname, ent_guid_str, sizeof(dkw.dkw_wname));
263 		else {
264 			c = dkw.dkw_wname;
265 			r = sizeof(dkw.dkw_wname) - 1;
266 			for (j = 0; j < __arraycount(ent->ent_name)
267 			    && ent->ent_name[j] != 0x0000; j++) {
268 				n = wput_utf8(c, r, le16toh(ent->ent_name[j]));
269 				if (n == 0)
270 					break;
271 				c += n; r -= n;
272 			}
273 			*c = '\0';
274 		}
275 
276 		/*
277 		 * Try with the partition name first.  If that fails,
278 		 * use the GUID string.  If that fails, punt.
279 		 */
280 		if ((error = dkwedge_add(&dkw)) == EEXIST &&
281 		    strcmp(dkw.dkw_wname, ent_guid_str) != 0) {
282 			char orig[sizeof(dkw.dkw_wname)];
283 			strlcpy(orig, dkw.dkw_wname, sizeof(orig));
284 			strlcpy(dkw.dkw_wname, ent_guid_str, sizeof(dkw.dkw_wname));
285 			error = dkwedge_add(&dkw);
286 			if (!error)
287 				aprint_error("%s: wedge named '%s' already "
288 				    "existed, using '%s'\n", pdk->dk_name,
289 				    orig, ent_guid_str);
290 		}
291 		if (error == EEXIST)
292 			aprint_error("%s: wedge named '%s' already exists, "
293 			    "manual intervention required\n", pdk->dk_name,
294 			    dkw.dkw_wname);
295 		else if (error)
296 			aprint_error("%s: error %d adding entry %u (%s), "
297 			    "type %s\n", pdk->dk_name, error, i, ent_guid_str,
298 			    ptype_guid_str);
299 	}
300 	error = 0;
301 
302  out:
303 	brelse(bp, 0);
304 	return (error);
305 }
306 
307 DKWEDGE_DISCOVERY_METHOD_DECL(GPT, 0, dkwedge_discover_gpt);
308