dkwedge_gpt.c revision 1.6
1 /* $NetBSD: dkwedge_gpt.c,v 1.6 2007/03/04 06:01:45 christos 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 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the NetBSD 21 * Foundation, Inc. and its contributors. 22 * 4. Neither the name of The NetBSD Foundation nor the names of its 23 * contributors may be used to endorse or promote products derived 24 * from this software without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 29 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 36 * POSSIBILITY OF SUCH DAMAGE. 37 */ 38 39 /* 40 * EFI GUID Partition Table support for disk wedges 41 */ 42 43 #include <sys/cdefs.h> 44 __KERNEL_RCSID(0, "$NetBSD: dkwedge_gpt.c,v 1.6 2007/03/04 06:01:45 christos Exp $"); 45 46 #include <sys/param.h> 47 #include <sys/systm.h> 48 #include <sys/proc.h> 49 #include <sys/errno.h> 50 #include <sys/disk.h> 51 #include <sys/vnode.h> 52 #include <sys/malloc.h> 53 54 #include <sys/disklabel_gpt.h> 55 #include <sys/uuid.h> 56 57 static const struct { 58 struct uuid ptype_guid; 59 const char *ptype_str; 60 } gpt_ptype_guid_to_str_tab[] = { 61 { GPT_ENT_TYPE_EFI, "msdos" }, /* XXX yes? */ 62 #if 0 63 { GPT_ENT_TYPE_FREEBSD, ??? }, 64 #endif 65 { GPT_ENT_TYPE_FREEBSD_SWAP, "swap" }, /* XXX for now */ 66 { GPT_ENT_TYPE_FREEBSD_UFS, "ffs" }, /* XXX for now */ 67 68 /* XXX What about the MS and Linux types? */ 69 70 { { .time_low = 0 }, NULL }, 71 }; 72 73 static const char * 74 gpt_ptype_guid_to_str(const struct uuid *guid) 75 { 76 int i; 77 78 for (i = 0; gpt_ptype_guid_to_str_tab[i].ptype_str != NULL; i++) { 79 if (memcmp(&gpt_ptype_guid_to_str_tab[i].ptype_guid, 80 guid, sizeof(*guid)) == 0) 81 return (gpt_ptype_guid_to_str_tab[i].ptype_str); 82 } 83 84 return (NULL); 85 } 86 87 static const uint32_t gpt_crc_tab[16] = { 88 0x00000000U, 0x1db71064U, 0x3b6e20c8U, 0x26d930acU, 89 0x76dc4190U, 0x6b6b51f4U, 0x4db26158U, 0x5005713cU, 90 0xedb88320U, 0xf00f9344U, 0xd6d6a3e8U, 0xcb61b38cU, 91 0x9b64c2b0U, 0x86d3d2d4U, 0xa00ae278U, 0xbdbdf21cU 92 }; 93 94 static uint32_t 95 gpt_crc32(const void *vbuf, size_t len) 96 { 97 const uint8_t *buf = vbuf; 98 uint32_t crc; 99 100 crc = 0xffffffffU; 101 while (len--) { 102 crc ^= *buf++; 103 crc = (crc >> 4) ^ gpt_crc_tab[crc & 0xf]; 104 crc = (crc >> 4) ^ gpt_crc_tab[crc & 0xf]; 105 } 106 107 return (crc ^ 0xffffffffU); 108 } 109 110 static int 111 gpt_verify_header_crc(struct gpt_hdr *hdr) 112 { 113 uint32_t crc; 114 int rv; 115 116 crc = hdr->hdr_crc_self; 117 hdr->hdr_crc_self = 0; 118 rv = le32toh(crc) == gpt_crc32(hdr, le32toh(hdr->hdr_size)); 119 hdr->hdr_crc_self = crc; 120 121 return (rv); 122 } 123 124 static int 125 dkwedge_discover_gpt(struct disk *pdk, struct vnode *vp) 126 { 127 static const struct uuid ent_type_unused = GPT_ENT_TYPE_UNUSED; 128 static const char gpt_hdr_sig[] = GPT_HDR_SIG; 129 struct dkwedge_info dkw; 130 void *buf; 131 struct gpt_hdr *hdr; 132 struct gpt_ent *ent; 133 uint32_t entries, entsz; 134 daddr_t lba_start, lba_end, lba_table; 135 uint32_t gpe_crc; 136 int error; 137 u_int i; 138 139 buf = malloc(DEV_BSIZE, M_DEVBUF, M_WAITOK); 140 141 /* 142 * Note: We don't bother with a Legacy or Protective MBR 143 * here. If a GPT is found, then the search stops, and 144 * the GPT is authoritative. 145 */ 146 147 /* Read in the GPT Header. */ 148 error = dkwedge_read(pdk, vp, GPT_HDR_BLKNO, buf, DEV_BSIZE); 149 if (error) 150 goto out; 151 hdr = buf; 152 153 /* Validate it. */ 154 if (memcmp(gpt_hdr_sig, hdr->hdr_sig, sizeof(hdr->hdr_sig)) != 0) { 155 /* XXX Should check at end-of-disk. */ 156 error = ESRCH; 157 goto out; 158 } 159 if (hdr->hdr_revision != htole32(GPT_HDR_REVISION)) { 160 /* XXX Should check at end-of-disk. */ 161 error = ESRCH; 162 goto out; 163 } 164 if (le32toh(hdr->hdr_size) > DEV_BSIZE) { 165 /* XXX Should check at end-of-disk. */ 166 error = ESRCH; 167 goto out; 168 } 169 if (gpt_verify_header_crc(hdr) == 0) { 170 /* XXX Should check at end-of-disk. */ 171 error = ESRCH; 172 goto out; 173 } 174 175 /* XXX Now that we found it, should we validate the backup? */ 176 177 { 178 struct uuid disk_guid; 179 char guid_str[UUID_STR_LEN]; 180 uuid_dec_le(hdr->hdr_guid, &disk_guid); 181 uuid_snprintf(guid_str, sizeof(guid_str), &disk_guid); 182 aprint_verbose("%s: GPT GUID: %s\n", pdk->dk_name, guid_str); 183 } 184 185 entries = le32toh(hdr->hdr_entries); 186 entsz = roundup(le32toh(hdr->hdr_entsz), 8); 187 if (entsz > roundup(sizeof(struct gpt_ent), 8)) { 188 aprint_error("%s: bogus GPT entry size: %u\n", 189 pdk->dk_name, le32toh(hdr->hdr_entsz)); 190 error = EINVAL; 191 goto out; 192 } 193 gpe_crc = le32toh(hdr->hdr_crc_table); 194 195 /* XXX Clamp entries at 128 for now. */ 196 if (entries > 128) { 197 aprint_error("%s: WARNING: clamping number of GPT entries to " 198 "128 (was %u)\n", pdk->dk_name, entries); 199 entries = 128; 200 } 201 202 lba_start = le64toh(hdr->hdr_lba_start); 203 lba_end = le64toh(hdr->hdr_lba_end); 204 lba_table = le64toh(hdr->hdr_lba_table); 205 if (lba_start < 0 || lba_end < 0 || lba_table < 0) { 206 aprint_error("%s: GPT block numbers out of range\n", 207 pdk->dk_name); 208 error = EINVAL; 209 goto out; 210 } 211 212 free(buf, M_DEVBUF); 213 buf = malloc(roundup(entries * entsz, DEV_BSIZE), M_DEVBUF, M_WAITOK); 214 error = dkwedge_read(pdk, vp, lba_table, buf, 215 roundup(entries * entsz, DEV_BSIZE)); 216 if (error) { 217 /* XXX Should check alternate location. */ 218 aprint_error("%s: unable to read GPT partition array, " 219 "error = %d\n", pdk->dk_name, error); 220 goto out; 221 } 222 223 if (gpt_crc32(buf, entries * entsz) != gpe_crc) { 224 /* XXX Should check alternate location. */ 225 aprint_error("%s: bad GPT partition array CRC\n", 226 pdk->dk_name); 227 error = EINVAL; 228 goto out; 229 } 230 231 /* 232 * Walk the partitions, adding a wedge for each type we know about. 233 */ 234 for (i = 0; i < entries; i++) { 235 struct uuid ptype_guid, ent_guid; 236 const char *ptype; 237 int j; 238 char ptype_guid_str[UUID_STR_LEN], ent_guid_str[UUID_STR_LEN]; 239 240 ent = (struct gpt_ent *)((char *)buf + (i * entsz)); 241 242 uuid_dec_le(ent->ent_type, &ptype_guid); 243 if (memcmp(&ptype_guid, &ent_type_unused, 244 sizeof(ptype_guid)) == 0) 245 continue; 246 247 uuid_dec_le(ent->ent_guid, &ent_guid); 248 249 uuid_snprintf(ptype_guid_str, sizeof(ptype_guid_str), 250 &ptype_guid); 251 uuid_snprintf(ent_guid_str, sizeof(ent_guid_str), 252 &ent_guid); 253 254 /* Skip it if we don't grok this ptype. */ 255 if ((ptype = gpt_ptype_guid_to_str(&ptype_guid)) == NULL) { 256 /* 257 * XXX Should probably just add these... maybe 258 * XXX just have an empty ptype? 259 */ 260 aprint_verbose("%s: skipping entry %u (%s), type %s\n", 261 pdk->dk_name, i, ent_guid_str, ptype_guid_str); 262 continue; 263 } 264 strcpy(dkw.dkw_ptype, ptype); 265 266 strcpy(dkw.dkw_parent, pdk->dk_name); 267 dkw.dkw_offset = le64toh(ent->ent_lba_start); 268 dkw.dkw_size = le64toh(ent->ent_lba_end) - dkw.dkw_offset + 1; 269 270 /* XXX Make sure it falls within the disk's data area. */ 271 272 if (ent->ent_name[0] == 0x0000) 273 strcpy(dkw.dkw_wname, ent_guid_str); 274 else { 275 for (j = 0; ent->ent_name[j] != 0x0000; j++) { 276 /* XXX UTF-16 -> UTF-8 */ 277 dkw.dkw_wname[j] = 278 le16toh(ent->ent_name[j]) & 0xff; 279 } 280 dkw.dkw_wname[j] = '\0'; 281 } 282 283 /* 284 * Try with the partition name first. If that fails, 285 * use the GUID string. If that fails, punt. 286 */ 287 if ((error = dkwedge_add(&dkw)) == EEXIST) { 288 aprint_error("%s: wedge named '%s' already exists, " 289 "trying '%s'\n", pdk->dk_name, 290 dkw.dkw_wname, /* XXX Unicode */ 291 ent_guid_str); 292 strcpy(dkw.dkw_wname, ent_guid_str); 293 error = dkwedge_add(&dkw); 294 } 295 if (error == EEXIST) 296 aprint_error("%s: wedge named '%s' already exists, " 297 "manual intervention required\n", pdk->dk_name, 298 dkw.dkw_wname); 299 else if (error) 300 aprint_error("%s: error %d adding entry %u (%s), " 301 "type %s\n", pdk->dk_name, error, i, ent_guid_str, 302 ptype_guid_str); 303 } 304 error = 0; 305 306 out: 307 free(buf, M_DEVBUF); 308 return (error); 309 } 310 311 DKWEDGE_DISCOVERY_METHOD_DECL(GPT, 0, dkwedge_discover_gpt); 312
Indexes created Fri Oct 03 02:09:57 GMT 2025