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