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