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