1 /*- 2 * Copyright (c) 2007, 2008 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 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD$"); 29 30 #include <sys/param.h> 31 #include <sys/bio.h> 32 #include <sys/diskmbr.h> 33 #include <sys/endian.h> 34 #include <sys/kernel.h> 35 #include <sys/kobj.h> 36 #include <sys/limits.h> 37 #include <sys/lock.h> 38 #include <sys/malloc.h> 39 #include <sys/mutex.h> 40 #include <sys/queue.h> 41 #include <sys/sbuf.h> 42 #include <sys/systm.h> 43 #include <sys/sysctl.h> 44 #include <geom/geom.h> 45 #include <geom/part/g_part.h> 46 47 #include "g_part_if.h" 48 49 FEATURE(geom_part_mbr, "GEOM partitioning class for MBR support"); 50 51 #define MBRSIZE 512 52 53 struct g_part_mbr_table { 54 struct g_part_table base; 55 u_char mbr[MBRSIZE]; 56 }; 57 58 struct g_part_mbr_entry { 59 struct g_part_entry base; 60 struct dos_partition ent; 61 }; 62 63 static int g_part_mbr_add(struct g_part_table *, struct g_part_entry *, 64 struct g_part_parms *); 65 static int g_part_mbr_bootcode(struct g_part_table *, struct g_part_parms *); 66 static int g_part_mbr_create(struct g_part_table *, struct g_part_parms *); 67 static int g_part_mbr_destroy(struct g_part_table *, struct g_part_parms *); 68 static void g_part_mbr_dumpconf(struct g_part_table *, struct g_part_entry *, 69 struct sbuf *, const char *); 70 static int g_part_mbr_dumpto(struct g_part_table *, struct g_part_entry *); 71 static int g_part_mbr_modify(struct g_part_table *, struct g_part_entry *, 72 struct g_part_parms *); 73 static const char *g_part_mbr_name(struct g_part_table *, struct g_part_entry *, 74 char *, size_t); 75 static int g_part_mbr_probe(struct g_part_table *, struct g_consumer *); 76 static int g_part_mbr_read(struct g_part_table *, struct g_consumer *); 77 static int g_part_mbr_setunset(struct g_part_table *, struct g_part_entry *, 78 const char *, unsigned int); 79 static const char *g_part_mbr_type(struct g_part_table *, struct g_part_entry *, 80 char *, size_t); 81 static int g_part_mbr_write(struct g_part_table *, struct g_consumer *); 82 static int g_part_mbr_resize(struct g_part_table *, struct g_part_entry *, 83 struct g_part_parms *); 84 85 static kobj_method_t g_part_mbr_methods[] = { 86 KOBJMETHOD(g_part_add, g_part_mbr_add), 87 KOBJMETHOD(g_part_bootcode, g_part_mbr_bootcode), 88 KOBJMETHOD(g_part_create, g_part_mbr_create), 89 KOBJMETHOD(g_part_destroy, g_part_mbr_destroy), 90 KOBJMETHOD(g_part_dumpconf, g_part_mbr_dumpconf), 91 KOBJMETHOD(g_part_dumpto, g_part_mbr_dumpto), 92 KOBJMETHOD(g_part_modify, g_part_mbr_modify), 93 KOBJMETHOD(g_part_resize, g_part_mbr_resize), 94 KOBJMETHOD(g_part_name, g_part_mbr_name), 95 KOBJMETHOD(g_part_probe, g_part_mbr_probe), 96 KOBJMETHOD(g_part_read, g_part_mbr_read), 97 KOBJMETHOD(g_part_setunset, g_part_mbr_setunset), 98 KOBJMETHOD(g_part_type, g_part_mbr_type), 99 KOBJMETHOD(g_part_write, g_part_mbr_write), 100 { 0, 0 } 101 }; 102 103 static struct g_part_scheme g_part_mbr_scheme = { 104 "MBR", 105 g_part_mbr_methods, 106 sizeof(struct g_part_mbr_table), 107 .gps_entrysz = sizeof(struct g_part_mbr_entry), 108 .gps_minent = NDOSPART, 109 .gps_maxent = NDOSPART, 110 .gps_bootcodesz = MBRSIZE, 111 }; 112 G_PART_SCHEME_DECLARE(g_part_mbr); 113 114 static struct g_part_mbr_alias { 115 u_char typ; 116 int alias; 117 } mbr_alias_match[] = { 118 { DOSPTYP_386BSD, G_PART_ALIAS_FREEBSD }, 119 { DOSPTYP_EXT, G_PART_ALIAS_EBR }, 120 { DOSPTYP_NTFS, G_PART_ALIAS_MS_NTFS }, 121 { DOSPTYP_FAT32, G_PART_ALIAS_MS_FAT32 }, 122 { DOSPTYP_EXTLBA, G_PART_ALIAS_EBR }, 123 { DOSPTYP_LDM, G_PART_ALIAS_MS_LDM_DATA }, 124 { DOSPTYP_LINSWP, G_PART_ALIAS_LINUX_SWAP }, 125 { DOSPTYP_LINUX, G_PART_ALIAS_LINUX_DATA }, 126 { DOSPTYP_LINLVM, G_PART_ALIAS_LINUX_LVM }, 127 { DOSPTYP_LINRAID, G_PART_ALIAS_LINUX_RAID }, 128 { DOSPTYP_PPCBOOT, G_PART_ALIAS_FREEBSD_BOOT }, 129 { DOSPTYP_VMFS, G_PART_ALIAS_VMFS }, 130 { DOSPTYP_VMKDIAG, G_PART_ALIAS_VMKDIAG }, 131 }; 132 133 static int 134 mbr_parse_type(const char *type, u_char *dp_typ) 135 { 136 const char *alias; 137 char *endp; 138 long lt; 139 int i; 140 141 if (type[0] == '!') { 142 lt = strtol(type + 1, &endp, 0); 143 if (type[1] == '\0' || *endp != '\0' || lt <= 0 || lt >= 256) 144 return (EINVAL); 145 *dp_typ = (u_char)lt; 146 return (0); 147 } 148 for (i = 0; 149 i < sizeof(mbr_alias_match) / sizeof(mbr_alias_match[0]); i++) { 150 alias = g_part_alias_name(mbr_alias_match[i].alias); 151 if (strcasecmp(type, alias) == 0) { 152 *dp_typ = mbr_alias_match[i].typ; 153 return (0); 154 } 155 } 156 return (EINVAL); 157 } 158 159 static int 160 mbr_probe_bpb(u_char *bpb) 161 { 162 uint16_t secsz; 163 uint8_t clstsz; 164 165 #define PO2(x) ((x & (x - 1)) == 0) 166 secsz = le16dec(bpb); 167 if (secsz < 512 || secsz > 4096 || !PO2(secsz)) 168 return (0); 169 clstsz = bpb[2]; 170 if (clstsz < 1 || clstsz > 128 || !PO2(clstsz)) 171 return (0); 172 #undef PO2 173 174 return (1); 175 } 176 177 static void 178 mbr_set_chs(struct g_part_table *table, uint32_t lba, u_char *cylp, u_char *hdp, 179 u_char *secp) 180 { 181 uint32_t cyl, hd, sec; 182 183 sec = lba % table->gpt_sectors + 1; 184 lba /= table->gpt_sectors; 185 hd = lba % table->gpt_heads; 186 lba /= table->gpt_heads; 187 cyl = lba; 188 if (cyl > 1023) 189 sec = hd = cyl = ~0; 190 191 *cylp = cyl & 0xff; 192 *hdp = hd & 0xff; 193 *secp = (sec & 0x3f) | ((cyl >> 2) & 0xc0); 194 } 195 196 static int 197 g_part_mbr_add(struct g_part_table *basetable, struct g_part_entry *baseentry, 198 struct g_part_parms *gpp) 199 { 200 struct g_part_mbr_entry *entry; 201 struct g_part_mbr_table *table; 202 uint32_t start, size, sectors; 203 204 if (gpp->gpp_parms & G_PART_PARM_LABEL) 205 return (EINVAL); 206 207 sectors = basetable->gpt_sectors; 208 209 entry = (struct g_part_mbr_entry *)baseentry; 210 table = (struct g_part_mbr_table *)basetable; 211 212 start = gpp->gpp_start; 213 size = gpp->gpp_size; 214 if (size < sectors) 215 return (EINVAL); 216 if (start % sectors) { 217 size = size - sectors + (start % sectors); 218 start = start - (start % sectors) + sectors; 219 } 220 if (size % sectors) 221 size = size - (size % sectors); 222 if (size < sectors) 223 return (EINVAL); 224 225 if (baseentry->gpe_deleted) 226 bzero(&entry->ent, sizeof(entry->ent)); 227 228 KASSERT(baseentry->gpe_start <= start, ("%s", __func__)); 229 KASSERT(baseentry->gpe_end >= start + size - 1, ("%s", __func__)); 230 baseentry->gpe_start = start; 231 baseentry->gpe_end = start + size - 1; 232 entry->ent.dp_start = start; 233 entry->ent.dp_size = size; 234 mbr_set_chs(basetable, baseentry->gpe_start, &entry->ent.dp_scyl, 235 &entry->ent.dp_shd, &entry->ent.dp_ssect); 236 mbr_set_chs(basetable, baseentry->gpe_end, &entry->ent.dp_ecyl, 237 &entry->ent.dp_ehd, &entry->ent.dp_esect); 238 return (mbr_parse_type(gpp->gpp_type, &entry->ent.dp_typ)); 239 } 240 241 static int 242 g_part_mbr_bootcode(struct g_part_table *basetable, struct g_part_parms *gpp) 243 { 244 struct g_part_mbr_table *table; 245 uint32_t dsn; 246 247 if (gpp->gpp_codesize != MBRSIZE) 248 return (ENODEV); 249 250 table = (struct g_part_mbr_table *)basetable; 251 dsn = *(uint32_t *)(table->mbr + DOSDSNOFF); 252 bcopy(gpp->gpp_codeptr, table->mbr, DOSPARTOFF); 253 if (dsn != 0) 254 *(uint32_t *)(table->mbr + DOSDSNOFF) = dsn; 255 return (0); 256 } 257 258 static int 259 g_part_mbr_create(struct g_part_table *basetable, struct g_part_parms *gpp) 260 { 261 struct g_provider *pp; 262 struct g_part_mbr_table *table; 263 264 pp = gpp->gpp_provider; 265 if (pp->sectorsize < MBRSIZE) 266 return (ENOSPC); 267 268 basetable->gpt_first = basetable->gpt_sectors; 269 basetable->gpt_last = MIN(pp->mediasize / pp->sectorsize, 270 UINT32_MAX) - 1; 271 272 table = (struct g_part_mbr_table *)basetable; 273 le16enc(table->mbr + DOSMAGICOFFSET, DOSMAGIC); 274 return (0); 275 } 276 277 static int 278 g_part_mbr_destroy(struct g_part_table *basetable, struct g_part_parms *gpp) 279 { 280 281 /* Wipe the first sector to clear the partitioning. */ 282 basetable->gpt_smhead |= 1; 283 return (0); 284 } 285 286 static void 287 g_part_mbr_dumpconf(struct g_part_table *table, struct g_part_entry *baseentry, 288 struct sbuf *sb, const char *indent) 289 { 290 struct g_part_mbr_entry *entry; 291 292 entry = (struct g_part_mbr_entry *)baseentry; 293 if (indent == NULL) { 294 /* conftxt: libdisk compatibility */ 295 sbuf_printf(sb, " xs MBR xt %u", entry->ent.dp_typ); 296 } else if (entry != NULL) { 297 /* confxml: partition entry information */ 298 sbuf_printf(sb, "%s<rawtype>%u</rawtype>\n", indent, 299 entry->ent.dp_typ); 300 if (entry->ent.dp_flag & 0x80) 301 sbuf_printf(sb, "%s<attrib>active</attrib>\n", indent); 302 } else { 303 /* confxml: scheme information */ 304 } 305 } 306 307 static int 308 g_part_mbr_dumpto(struct g_part_table *table, struct g_part_entry *baseentry) 309 { 310 struct g_part_mbr_entry *entry; 311 312 /* Allow dumping to a FreeBSD partition or Linux swap partition only. */ 313 entry = (struct g_part_mbr_entry *)baseentry; 314 return ((entry->ent.dp_typ == DOSPTYP_386BSD || 315 entry->ent.dp_typ == DOSPTYP_LINSWP) ? 1 : 0); 316 } 317 318 static int 319 g_part_mbr_modify(struct g_part_table *basetable, 320 struct g_part_entry *baseentry, struct g_part_parms *gpp) 321 { 322 struct g_part_mbr_entry *entry; 323 324 if (gpp->gpp_parms & G_PART_PARM_LABEL) 325 return (EINVAL); 326 327 entry = (struct g_part_mbr_entry *)baseentry; 328 if (gpp->gpp_parms & G_PART_PARM_TYPE) 329 return (mbr_parse_type(gpp->gpp_type, &entry->ent.dp_typ)); 330 return (0); 331 } 332 333 static int 334 g_part_mbr_resize(struct g_part_table *basetable, 335 struct g_part_entry *baseentry, struct g_part_parms *gpp) 336 { 337 struct g_part_mbr_entry *entry; 338 uint32_t size, sectors; 339 340 sectors = basetable->gpt_sectors; 341 size = gpp->gpp_size; 342 343 if (size < sectors) 344 return (EINVAL); 345 if (size % sectors) 346 size = size - (size % sectors); 347 if (size < sectors) 348 return (EINVAL); 349 350 entry = (struct g_part_mbr_entry *)baseentry; 351 baseentry->gpe_end = baseentry->gpe_start + size - 1; 352 entry->ent.dp_size = size; 353 mbr_set_chs(basetable, baseentry->gpe_end, &entry->ent.dp_ecyl, 354 &entry->ent.dp_ehd, &entry->ent.dp_esect); 355 return (0); 356 } 357 358 static const char * 359 g_part_mbr_name(struct g_part_table *table, struct g_part_entry *baseentry, 360 char *buf, size_t bufsz) 361 { 362 363 snprintf(buf, bufsz, "s%d", baseentry->gpe_index); 364 return (buf); 365 } 366 367 static int 368 g_part_mbr_probe(struct g_part_table *table, struct g_consumer *cp) 369 { 370 char psn[8]; 371 struct g_provider *pp; 372 u_char *buf, *p; 373 int error, index, res, sum; 374 uint16_t magic; 375 376 pp = cp->provider; 377 378 /* Sanity-check the provider. */ 379 if (pp->sectorsize < MBRSIZE || pp->mediasize < pp->sectorsize) 380 return (ENOSPC); 381 if (pp->sectorsize > 4096) 382 return (ENXIO); 383 384 /* We don't nest under an MBR (see EBR instead). */ 385 error = g_getattr("PART::scheme", cp, &psn); 386 if (error == 0 && strcmp(psn, g_part_mbr_scheme.name) == 0) 387 return (ELOOP); 388 389 /* Check that there's a MBR. */ 390 buf = g_read_data(cp, 0L, pp->sectorsize, &error); 391 if (buf == NULL) 392 return (error); 393 394 /* We goto out on mismatch. */ 395 res = ENXIO; 396 397 magic = le16dec(buf + DOSMAGICOFFSET); 398 if (magic != DOSMAGIC) 399 goto out; 400 401 for (index = 0; index < NDOSPART; index++) { 402 p = buf + DOSPARTOFF + index * DOSPARTSIZE; 403 if (p[0] != 0 && p[0] != 0x80) 404 goto out; 405 } 406 407 /* 408 * If the partition table does not consist of all zeroes, 409 * assume we have a MBR. If it's all zeroes, we could have 410 * a boot sector. For example, a boot sector that doesn't 411 * have boot code -- common on non-i386 hardware. In that 412 * case we check if we have a possible BPB. If so, then we 413 * assume we have a boot sector instead. 414 */ 415 sum = 0; 416 for (index = 0; index < NDOSPART * DOSPARTSIZE; index++) 417 sum += buf[DOSPARTOFF + index]; 418 if (sum != 0 || !mbr_probe_bpb(buf + 0x0b)) 419 res = G_PART_PROBE_PRI_NORM; 420 421 out: 422 g_free(buf); 423 return (res); 424 } 425 426 static int 427 g_part_mbr_read(struct g_part_table *basetable, struct g_consumer *cp) 428 { 429 struct dos_partition ent; 430 struct g_provider *pp; 431 struct g_part_mbr_table *table; 432 struct g_part_mbr_entry *entry; 433 u_char *buf, *p; 434 off_t chs, msize, first; 435 u_int sectors, heads; 436 int error, index; 437 438 pp = cp->provider; 439 table = (struct g_part_mbr_table *)basetable; 440 first = basetable->gpt_sectors; 441 msize = MIN(pp->mediasize / pp->sectorsize, UINT32_MAX); 442 443 buf = g_read_data(cp, 0L, pp->sectorsize, &error); 444 if (buf == NULL) 445 return (error); 446 447 bcopy(buf, table->mbr, sizeof(table->mbr)); 448 for (index = NDOSPART - 1; index >= 0; index--) { 449 p = buf + DOSPARTOFF + index * DOSPARTSIZE; 450 ent.dp_flag = p[0]; 451 ent.dp_shd = p[1]; 452 ent.dp_ssect = p[2]; 453 ent.dp_scyl = p[3]; 454 ent.dp_typ = p[4]; 455 ent.dp_ehd = p[5]; 456 ent.dp_esect = p[6]; 457 ent.dp_ecyl = p[7]; 458 ent.dp_start = le32dec(p + 8); 459 ent.dp_size = le32dec(p + 12); 460 if (ent.dp_typ == 0 || ent.dp_typ == DOSPTYP_PMBR) 461 continue; 462 if (ent.dp_start == 0 || ent.dp_size == 0) 463 continue; 464 sectors = ent.dp_esect & 0x3f; 465 if (sectors > basetable->gpt_sectors && 466 !basetable->gpt_fixgeom) { 467 g_part_geometry_heads(msize, sectors, &chs, &heads); 468 if (chs != 0) { 469 basetable->gpt_sectors = sectors; 470 basetable->gpt_heads = heads; 471 } 472 } 473 if (ent.dp_start < first) 474 first = ent.dp_start; 475 entry = (struct g_part_mbr_entry *)g_part_new_entry(basetable, 476 index + 1, ent.dp_start, ent.dp_start + ent.dp_size - 1); 477 entry->ent = ent; 478 } 479 480 basetable->gpt_entries = NDOSPART; 481 basetable->gpt_first = basetable->gpt_sectors; 482 basetable->gpt_last = msize - 1; 483 484 if (first < basetable->gpt_first) 485 basetable->gpt_first = 1; 486 487 g_free(buf); 488 return (0); 489 } 490 491 static int 492 g_part_mbr_setunset(struct g_part_table *table, struct g_part_entry *baseentry, 493 const char *attrib, unsigned int set) 494 { 495 struct g_part_entry *iter; 496 struct g_part_mbr_entry *entry; 497 int changed; 498 499 if (strcasecmp(attrib, "active") != 0) 500 return (EINVAL); 501 502 /* Only one entry can have the active attribute. */ 503 LIST_FOREACH(iter, &table->gpt_entry, gpe_entry) { 504 if (iter->gpe_deleted) 505 continue; 506 changed = 0; 507 entry = (struct g_part_mbr_entry *)iter; 508 if (iter == baseentry) { 509 if (set && (entry->ent.dp_flag & 0x80) == 0) { 510 entry->ent.dp_flag |= 0x80; 511 changed = 1; 512 } else if (!set && (entry->ent.dp_flag & 0x80)) { 513 entry->ent.dp_flag &= ~0x80; 514 changed = 1; 515 } 516 } else { 517 if (set && (entry->ent.dp_flag & 0x80)) { 518 entry->ent.dp_flag &= ~0x80; 519 changed = 1; 520 } 521 } 522 if (changed && !iter->gpe_created) 523 iter->gpe_modified = 1; 524 } 525 return (0); 526 } 527 528 static const char * 529 g_part_mbr_type(struct g_part_table *basetable, struct g_part_entry *baseentry, 530 char *buf, size_t bufsz) 531 { 532 struct g_part_mbr_entry *entry; 533 int i; 534 535 entry = (struct g_part_mbr_entry *)baseentry; 536 for (i = 0; 537 i < sizeof(mbr_alias_match) / sizeof(mbr_alias_match[0]); i++) { 538 if (mbr_alias_match[i].typ == entry->ent.dp_typ) 539 return (g_part_alias_name(mbr_alias_match[i].alias)); 540 } 541 snprintf(buf, bufsz, "!%d", entry->ent.dp_typ); 542 return (buf); 543 } 544 545 static int 546 g_part_mbr_write(struct g_part_table *basetable, struct g_consumer *cp) 547 { 548 struct g_part_entry *baseentry; 549 struct g_part_mbr_entry *entry; 550 struct g_part_mbr_table *table; 551 u_char *p; 552 int error, index; 553 554 table = (struct g_part_mbr_table *)basetable; 555 baseentry = LIST_FIRST(&basetable->gpt_entry); 556 for (index = 1; index <= basetable->gpt_entries; index++) { 557 p = table->mbr + DOSPARTOFF + (index - 1) * DOSPARTSIZE; 558 entry = (baseentry != NULL && index == baseentry->gpe_index) 559 ? (struct g_part_mbr_entry *)baseentry : NULL; 560 if (entry != NULL && !baseentry->gpe_deleted) { 561 p[0] = entry->ent.dp_flag; 562 p[1] = entry->ent.dp_shd; 563 p[2] = entry->ent.dp_ssect; 564 p[3] = entry->ent.dp_scyl; 565 p[4] = entry->ent.dp_typ; 566 p[5] = entry->ent.dp_ehd; 567 p[6] = entry->ent.dp_esect; 568 p[7] = entry->ent.dp_ecyl; 569 le32enc(p + 8, entry->ent.dp_start); 570 le32enc(p + 12, entry->ent.dp_size); 571 } else 572 bzero(p, DOSPARTSIZE); 573 574 if (entry != NULL) 575 baseentry = LIST_NEXT(baseentry, gpe_entry); 576 } 577 578 error = g_write_data(cp, 0, table->mbr, cp->provider->sectorsize); 579 return (error); 580 } 581