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 <geom/geom.h> 44 #include <geom/part/g_part.h> 45 46 #include "g_part_if.h" 47 48 #define MBRSIZE 512 49 50 struct g_part_mbr_table { 51 struct g_part_table base; 52 u_char mbr[MBRSIZE]; 53 }; 54 55 struct g_part_mbr_entry { 56 struct g_part_entry base; 57 struct dos_partition ent; 58 }; 59 60 static int g_part_mbr_add(struct g_part_table *, struct g_part_entry *, 61 struct g_part_parms *); 62 static int g_part_mbr_bootcode(struct g_part_table *, struct g_part_parms *); 63 static int g_part_mbr_create(struct g_part_table *, struct g_part_parms *); 64 static int g_part_mbr_destroy(struct g_part_table *, struct g_part_parms *); 65 static int g_part_mbr_dumpconf(struct g_part_table *, struct g_part_entry *, 66 struct sbuf *, const char *); 67 static int g_part_mbr_dumpto(struct g_part_table *, struct g_part_entry *); 68 static int g_part_mbr_modify(struct g_part_table *, struct g_part_entry *, 69 struct g_part_parms *); 70 static char *g_part_mbr_name(struct g_part_table *, struct g_part_entry *, 71 char *, size_t); 72 static int g_part_mbr_probe(struct g_part_table *, struct g_consumer *); 73 static int g_part_mbr_read(struct g_part_table *, struct g_consumer *); 74 static int g_part_mbr_setunset(struct g_part_table *, struct g_part_entry *, 75 const char *, unsigned int); 76 static const char *g_part_mbr_type(struct g_part_table *, struct g_part_entry *, 77 char *, size_t); 78 static int g_part_mbr_write(struct g_part_table *, struct g_consumer *); 79 80 static kobj_method_t g_part_mbr_methods[] = { 81 KOBJMETHOD(g_part_add, g_part_mbr_add), 82 KOBJMETHOD(g_part_bootcode, g_part_mbr_bootcode), 83 KOBJMETHOD(g_part_create, g_part_mbr_create), 84 KOBJMETHOD(g_part_destroy, g_part_mbr_destroy), 85 KOBJMETHOD(g_part_dumpconf, g_part_mbr_dumpconf), 86 KOBJMETHOD(g_part_dumpto, g_part_mbr_dumpto), 87 KOBJMETHOD(g_part_modify, g_part_mbr_modify), 88 KOBJMETHOD(g_part_name, g_part_mbr_name), 89 KOBJMETHOD(g_part_probe, g_part_mbr_probe), 90 KOBJMETHOD(g_part_read, g_part_mbr_read), 91 KOBJMETHOD(g_part_setunset, g_part_mbr_setunset), 92 KOBJMETHOD(g_part_type, g_part_mbr_type), 93 KOBJMETHOD(g_part_write, g_part_mbr_write), 94 { 0, 0 } 95 }; 96 97 static struct g_part_scheme g_part_mbr_scheme = { 98 "MBR", 99 g_part_mbr_methods, 100 sizeof(struct g_part_mbr_table), 101 .gps_entrysz = sizeof(struct g_part_mbr_entry), 102 .gps_minent = NDOSPART, 103 .gps_maxent = NDOSPART, 104 .gps_bootcodesz = MBRSIZE, 105 }; 106 G_PART_SCHEME_DECLARE(g_part_mbr); 107 108 static int 109 mbr_parse_type(const char *type, u_char *dp_typ) 110 { 111 const char *alias; 112 char *endp; 113 long lt; 114 115 if (type[0] == '!') { 116 lt = strtol(type + 1, &endp, 0); 117 if (type[1] == '\0' || *endp != '\0' || lt <= 0 || lt >= 256) 118 return (EINVAL); 119 *dp_typ = (u_char)lt; 120 return (0); 121 } 122 alias = g_part_alias_name(G_PART_ALIAS_FREEBSD); 123 if (!strcasecmp(type, alias)) { 124 *dp_typ = DOSPTYP_386BSD; 125 return (0); 126 } 127 return (EINVAL); 128 } 129 130 static int 131 mbr_probe_bpb(u_char *bpb) 132 { 133 uint16_t secsz; 134 uint8_t clstsz; 135 136 #define PO2(x) ((x & (x - 1)) == 0) 137 secsz = le16dec(bpb); 138 if (secsz < 512 || secsz > 4096 || !PO2(secsz)) 139 return (0); 140 clstsz = bpb[2]; 141 if (clstsz < 1 || clstsz > 128 || !PO2(clstsz)) 142 return (0); 143 #undef PO2 144 145 return (1); 146 } 147 148 static void 149 mbr_set_chs(struct g_part_table *table, uint32_t lba, u_char *cylp, u_char *hdp, 150 u_char *secp) 151 { 152 uint32_t cyl, hd, sec; 153 154 sec = lba % table->gpt_sectors + 1; 155 lba /= table->gpt_sectors; 156 hd = lba % table->gpt_heads; 157 lba /= table->gpt_heads; 158 cyl = lba; 159 if (cyl > 1023) 160 sec = hd = cyl = ~0; 161 162 *cylp = cyl & 0xff; 163 *hdp = hd & 0xff; 164 *secp = (sec & 0x3f) | ((cyl >> 2) & 0xc0); 165 } 166 167 static int 168 g_part_mbr_add(struct g_part_table *basetable, struct g_part_entry *baseentry, 169 struct g_part_parms *gpp) 170 { 171 struct g_part_mbr_entry *entry; 172 struct g_part_mbr_table *table; 173 uint32_t start, size, sectors; 174 175 if (gpp->gpp_parms & G_PART_PARM_LABEL) 176 return (EINVAL); 177 178 sectors = basetable->gpt_sectors; 179 180 entry = (struct g_part_mbr_entry *)baseentry; 181 table = (struct g_part_mbr_table *)basetable; 182 183 start = gpp->gpp_start; 184 size = gpp->gpp_size; 185 if (size < sectors) 186 return (EINVAL); 187 if (start % sectors) { 188 size = size - sectors + (start % sectors); 189 start = start - (start % sectors) + sectors; 190 } 191 if (size % sectors) 192 size = size - (size % sectors); 193 if (size < sectors) 194 return (EINVAL); 195 196 if (baseentry->gpe_deleted) 197 bzero(&entry->ent, sizeof(entry->ent)); 198 199 KASSERT(baseentry->gpe_start <= start, (__func__)); 200 KASSERT(baseentry->gpe_end >= start + size - 1, (__func__)); 201 baseentry->gpe_start = start; 202 baseentry->gpe_end = start + size - 1; 203 entry->ent.dp_start = start; 204 entry->ent.dp_size = size; 205 mbr_set_chs(basetable, baseentry->gpe_start, &entry->ent.dp_scyl, 206 &entry->ent.dp_shd, &entry->ent.dp_ssect); 207 mbr_set_chs(basetable, baseentry->gpe_end, &entry->ent.dp_ecyl, 208 &entry->ent.dp_ehd, &entry->ent.dp_esect); 209 return (mbr_parse_type(gpp->gpp_type, &entry->ent.dp_typ)); 210 } 211 212 static int 213 g_part_mbr_bootcode(struct g_part_table *basetable, struct g_part_parms *gpp) 214 { 215 struct g_part_mbr_table *table; 216 size_t codesz; 217 218 codesz = DOSPARTOFF; 219 table = (struct g_part_mbr_table *)basetable; 220 bzero(table->mbr, codesz); 221 codesz = MIN(codesz, gpp->gpp_codesize); 222 if (codesz > 0) 223 bcopy(gpp->gpp_codeptr, table->mbr, codesz); 224 return (0); 225 } 226 227 static int 228 g_part_mbr_create(struct g_part_table *basetable, struct g_part_parms *gpp) 229 { 230 struct g_consumer *cp; 231 struct g_provider *pp; 232 struct g_part_mbr_table *table; 233 uint64_t msize; 234 235 pp = gpp->gpp_provider; 236 cp = LIST_FIRST(&pp->consumers); 237 238 if (pp->sectorsize < MBRSIZE) 239 return (ENOSPC); 240 241 msize = pp->mediasize / pp->sectorsize; 242 basetable->gpt_first = basetable->gpt_sectors; 243 basetable->gpt_last = msize - (msize % basetable->gpt_sectors) - 1; 244 245 table = (struct g_part_mbr_table *)basetable; 246 le16enc(table->mbr + DOSMAGICOFFSET, DOSMAGIC); 247 return (0); 248 } 249 250 static int 251 g_part_mbr_destroy(struct g_part_table *basetable, struct g_part_parms *gpp) 252 { 253 254 /* Wipe the first sector to clear the partitioning. */ 255 basetable->gpt_smhead |= 1; 256 return (0); 257 } 258 259 static int 260 g_part_mbr_dumpconf(struct g_part_table *table, struct g_part_entry *baseentry, 261 struct sbuf *sb, const char *indent) 262 { 263 struct g_part_mbr_entry *entry; 264 265 entry = (struct g_part_mbr_entry *)baseentry; 266 if (indent == NULL) { 267 /* conftxt: libdisk compatibility */ 268 sbuf_printf(sb, " xs MBR xt %u", entry->ent.dp_typ); 269 } else if (entry != NULL) { 270 /* confxml: partition entry information */ 271 sbuf_printf(sb, "%s<rawtype>%u</rawtype>\n", indent, 272 entry->ent.dp_typ); 273 if (entry->ent.dp_flag & 0x80) 274 sbuf_printf(sb, "%s<attrib>active</attrib>\n", indent); 275 } else { 276 /* confxml: scheme information */ 277 } 278 return (0); 279 } 280 281 static int 282 g_part_mbr_dumpto(struct g_part_table *table, struct g_part_entry *baseentry) 283 { 284 struct g_part_mbr_entry *entry; 285 286 /* Allow dumping to a FreeBSD partition only. */ 287 entry = (struct g_part_mbr_entry *)baseentry; 288 return ((entry->ent.dp_typ == DOSPTYP_386BSD) ? 1 : 0); 289 } 290 291 static int 292 g_part_mbr_modify(struct g_part_table *basetable, 293 struct g_part_entry *baseentry, struct g_part_parms *gpp) 294 { 295 struct g_part_mbr_entry *entry; 296 297 if (gpp->gpp_parms & G_PART_PARM_LABEL) 298 return (EINVAL); 299 300 entry = (struct g_part_mbr_entry *)baseentry; 301 if (gpp->gpp_parms & G_PART_PARM_TYPE) 302 return (mbr_parse_type(gpp->gpp_type, &entry->ent.dp_typ)); 303 return (0); 304 } 305 306 static char * 307 g_part_mbr_name(struct g_part_table *table, struct g_part_entry *baseentry, 308 char *buf, size_t bufsz) 309 { 310 311 snprintf(buf, bufsz, "s%d", baseentry->gpe_index); 312 return (buf); 313 } 314 315 static int 316 g_part_mbr_probe(struct g_part_table *table, struct g_consumer *cp) 317 { 318 struct g_provider *pp; 319 u_char *buf, *p; 320 int error, index, res, sum; 321 uint16_t magic; 322 323 pp = cp->provider; 324 325 /* Sanity-check the provider. */ 326 if (pp->sectorsize < MBRSIZE || pp->mediasize < pp->sectorsize) 327 return (ENOSPC); 328 if (pp->sectorsize > 4096) 329 return (ENXIO); 330 331 /* Check that there's a MBR. */ 332 buf = g_read_data(cp, 0L, pp->sectorsize, &error); 333 if (buf == NULL) 334 return (error); 335 336 /* We goto out on mismatch. */ 337 res = ENXIO; 338 339 magic = le16dec(buf + DOSMAGICOFFSET); 340 if (magic != DOSMAGIC) 341 goto out; 342 343 for (index = 0; index < NDOSPART; index++) { 344 p = buf + DOSPARTOFF + index * DOSPARTSIZE; 345 if (p[0] != 0 && p[0] != 0x80) 346 goto out; 347 } 348 349 /* 350 * If the partition table does not consist of all zeroes, 351 * assume we have a MBR. If it's all zeroes, we could have 352 * a boot sector. For example, a boot sector that doesn't 353 * have boot code -- common on non-i386 hardware. In that 354 * case we check if we have a possible BPB. If so, then we 355 * assume we have a boot sector instead. 356 */ 357 sum = 0; 358 for (index = 0; index < NDOSPART * DOSPARTSIZE; index++) 359 sum += buf[DOSPARTOFF + index]; 360 if (sum != 0 || !mbr_probe_bpb(buf + 0x0b)) 361 res = G_PART_PROBE_PRI_NORM; 362 363 out: 364 g_free(buf); 365 return (res); 366 } 367 368 static int 369 g_part_mbr_read(struct g_part_table *basetable, struct g_consumer *cp) 370 { 371 struct dos_partition ent; 372 struct g_provider *pp; 373 struct g_part_mbr_table *table; 374 struct g_part_mbr_entry *entry; 375 u_char *buf, *p; 376 off_t chs, msize; 377 u_int sectors, heads; 378 int error, index; 379 380 pp = cp->provider; 381 table = (struct g_part_mbr_table *)basetable; 382 msize = pp->mediasize / pp->sectorsize; 383 384 buf = g_read_data(cp, 0L, pp->sectorsize, &error); 385 if (buf == NULL) 386 return (error); 387 388 bcopy(buf, table->mbr, sizeof(table->mbr)); 389 for (index = NDOSPART - 1; index >= 0; index--) { 390 p = buf + DOSPARTOFF + index * DOSPARTSIZE; 391 ent.dp_flag = p[0]; 392 ent.dp_shd = p[1]; 393 ent.dp_ssect = p[2]; 394 ent.dp_scyl = p[3]; 395 ent.dp_typ = p[4]; 396 ent.dp_ehd = p[5]; 397 ent.dp_esect = p[6]; 398 ent.dp_ecyl = p[7]; 399 ent.dp_start = le32dec(p + 8); 400 ent.dp_size = le32dec(p + 12); 401 if (ent.dp_typ == 0 || ent.dp_typ == DOSPTYP_PMBR) 402 continue; 403 if (ent.dp_start == 0 || ent.dp_size == 0) 404 continue; 405 sectors = ent.dp_esect & 0x3f; 406 if (sectors > basetable->gpt_sectors && 407 !basetable->gpt_fixgeom) { 408 g_part_geometry_heads(msize, sectors, &chs, &heads); 409 if (chs != 0) { 410 basetable->gpt_sectors = sectors; 411 basetable->gpt_heads = heads; 412 } 413 } 414 if ((ent.dp_start % basetable->gpt_sectors) != 0) 415 printf("GEOM: %s: partition %d does not start on a " 416 "track boundary.\n", pp->name, index + 1); 417 if ((ent.dp_size % basetable->gpt_sectors) != 0) 418 printf("GEOM: %s: partition %d does not end on a " 419 "track boundary.\n", pp->name, index + 1); 420 421 entry = (struct g_part_mbr_entry *)g_part_new_entry(basetable, 422 index + 1, ent.dp_start, ent.dp_start + ent.dp_size - 1); 423 entry->ent = ent; 424 } 425 426 basetable->gpt_entries = NDOSPART; 427 basetable->gpt_first = basetable->gpt_sectors; 428 basetable->gpt_last = msize - (msize % basetable->gpt_sectors) - 1; 429 430 return (0); 431 } 432 433 static int 434 g_part_mbr_setunset(struct g_part_table *table, struct g_part_entry *baseentry, 435 const char *attrib, unsigned int set) 436 { 437 struct g_part_entry *iter; 438 struct g_part_mbr_entry *entry; 439 int changed; 440 441 if (strcasecmp(attrib, "active") != 0) 442 return (EINVAL); 443 444 /* Only one entry can have the active attribute. */ 445 LIST_FOREACH(iter, &table->gpt_entry, gpe_entry) { 446 if (iter->gpe_deleted) 447 continue; 448 changed = 0; 449 entry = (struct g_part_mbr_entry *)iter; 450 if (iter == baseentry) { 451 if (set && (entry->ent.dp_flag & 0x80) == 0) { 452 entry->ent.dp_flag |= 0x80; 453 changed = 1; 454 } else if (!set && (entry->ent.dp_flag & 0x80)) { 455 entry->ent.dp_flag &= ~0x80; 456 changed = 1; 457 } 458 } else { 459 if (set && (entry->ent.dp_flag & 0x80)) { 460 entry->ent.dp_flag &= ~0x80; 461 changed = 1; 462 } 463 } 464 if (changed && !iter->gpe_created) 465 iter->gpe_modified = 1; 466 } 467 return (0); 468 } 469 470 static const char * 471 g_part_mbr_type(struct g_part_table *basetable, struct g_part_entry *baseentry, 472 char *buf, size_t bufsz) 473 { 474 struct g_part_mbr_entry *entry; 475 int type; 476 477 entry = (struct g_part_mbr_entry *)baseentry; 478 type = entry->ent.dp_typ; 479 if (type == DOSPTYP_386BSD) 480 return (g_part_alias_name(G_PART_ALIAS_FREEBSD)); 481 snprintf(buf, bufsz, "!%d", type); 482 return (buf); 483 } 484 485 static int 486 g_part_mbr_write(struct g_part_table *basetable, struct g_consumer *cp) 487 { 488 struct g_part_entry *baseentry; 489 struct g_part_mbr_entry *entry; 490 struct g_part_mbr_table *table; 491 u_char *p; 492 int error, index; 493 494 table = (struct g_part_mbr_table *)basetable; 495 baseentry = LIST_FIRST(&basetable->gpt_entry); 496 for (index = 1; index <= basetable->gpt_entries; index++) { 497 p = table->mbr + DOSPARTOFF + (index - 1) * DOSPARTSIZE; 498 entry = (baseentry != NULL && index == baseentry->gpe_index) 499 ? (struct g_part_mbr_entry *)baseentry : NULL; 500 if (entry != NULL && !baseentry->gpe_deleted) { 501 p[0] = entry->ent.dp_flag; 502 p[1] = entry->ent.dp_shd; 503 p[2] = entry->ent.dp_ssect; 504 p[3] = entry->ent.dp_scyl; 505 p[4] = entry->ent.dp_typ; 506 p[5] = entry->ent.dp_ehd; 507 p[6] = entry->ent.dp_esect; 508 p[7] = entry->ent.dp_ecyl; 509 le32enc(p + 8, entry->ent.dp_start); 510 le32enc(p + 12, entry->ent.dp_size); 511 } else 512 bzero(p, DOSPARTSIZE); 513 514 if (entry != NULL) 515 baseentry = LIST_NEXT(baseentry, gpe_entry); 516 } 517 518 error = g_write_data(cp, 0, table->mbr, cp->provider->sectorsize); 519 return (error); 520 } 521