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; 216 217 table = (struct g_part_mbr_table *)basetable; 218 bcopy(gpp->gpp_codeptr, table->mbr, DOSPARTOFF); 219 return (0); 220 } 221 222 static int 223 g_part_mbr_create(struct g_part_table *basetable, struct g_part_parms *gpp) 224 { 225 struct g_consumer *cp; 226 struct g_provider *pp; 227 struct g_part_mbr_table *table; 228 uint64_t msize; 229 230 pp = gpp->gpp_provider; 231 cp = LIST_FIRST(&pp->consumers); 232 233 if (pp->sectorsize < MBRSIZE) 234 return (ENOSPC); 235 236 msize = pp->mediasize / pp->sectorsize; 237 basetable->gpt_first = basetable->gpt_sectors; 238 basetable->gpt_last = msize - (msize % basetable->gpt_sectors) - 1; 239 240 table = (struct g_part_mbr_table *)basetable; 241 le16enc(table->mbr + DOSMAGICOFFSET, DOSMAGIC); 242 return (0); 243 } 244 245 static int 246 g_part_mbr_destroy(struct g_part_table *basetable, struct g_part_parms *gpp) 247 { 248 249 /* Wipe the first sector to clear the partitioning. */ 250 basetable->gpt_smhead |= 1; 251 return (0); 252 } 253 254 static int 255 g_part_mbr_dumpconf(struct g_part_table *table, struct g_part_entry *baseentry, 256 struct sbuf *sb, const char *indent) 257 { 258 struct g_part_mbr_entry *entry; 259 260 entry = (struct g_part_mbr_entry *)baseentry; 261 if (indent == NULL) { 262 /* conftxt: libdisk compatibility */ 263 sbuf_printf(sb, " xs MBR xt %u", entry->ent.dp_typ); 264 } else if (entry != NULL) { 265 /* confxml: partition entry information */ 266 sbuf_printf(sb, "%s<rawtype>%u</rawtype>\n", indent, 267 entry->ent.dp_typ); 268 if (entry->ent.dp_flag & 0x80) 269 sbuf_printf(sb, "%s<attrib>active</attrib>\n", indent); 270 } else { 271 /* confxml: scheme information */ 272 } 273 return (0); 274 } 275 276 static int 277 g_part_mbr_dumpto(struct g_part_table *table, struct g_part_entry *baseentry) 278 { 279 struct g_part_mbr_entry *entry; 280 281 /* Allow dumping to a FreeBSD partition only. */ 282 entry = (struct g_part_mbr_entry *)baseentry; 283 return ((entry->ent.dp_typ == DOSPTYP_386BSD) ? 1 : 0); 284 } 285 286 static int 287 g_part_mbr_modify(struct g_part_table *basetable, 288 struct g_part_entry *baseentry, struct g_part_parms *gpp) 289 { 290 struct g_part_mbr_entry *entry; 291 292 if (gpp->gpp_parms & G_PART_PARM_LABEL) 293 return (EINVAL); 294 295 entry = (struct g_part_mbr_entry *)baseentry; 296 if (gpp->gpp_parms & G_PART_PARM_TYPE) 297 return (mbr_parse_type(gpp->gpp_type, &entry->ent.dp_typ)); 298 return (0); 299 } 300 301 static char * 302 g_part_mbr_name(struct g_part_table *table, struct g_part_entry *baseentry, 303 char *buf, size_t bufsz) 304 { 305 306 snprintf(buf, bufsz, "s%d", baseentry->gpe_index); 307 return (buf); 308 } 309 310 static int 311 g_part_mbr_probe(struct g_part_table *table, struct g_consumer *cp) 312 { 313 struct g_provider *pp; 314 u_char *buf, *p; 315 int error, index, res, sum; 316 uint16_t magic; 317 318 pp = cp->provider; 319 320 /* Sanity-check the provider. */ 321 if (pp->sectorsize < MBRSIZE || pp->mediasize < pp->sectorsize) 322 return (ENOSPC); 323 if (pp->sectorsize > 4096) 324 return (ENXIO); 325 326 /* Check that there's a MBR. */ 327 buf = g_read_data(cp, 0L, pp->sectorsize, &error); 328 if (buf == NULL) 329 return (error); 330 331 /* We goto out on mismatch. */ 332 res = ENXIO; 333 334 magic = le16dec(buf + DOSMAGICOFFSET); 335 if (magic != DOSMAGIC) 336 goto out; 337 338 for (index = 0; index < NDOSPART; index++) { 339 p = buf + DOSPARTOFF + index * DOSPARTSIZE; 340 if (p[0] != 0 && p[0] != 0x80) 341 goto out; 342 } 343 344 /* 345 * If the partition table does not consist of all zeroes, 346 * assume we have a MBR. If it's all zeroes, we could have 347 * a boot sector. For example, a boot sector that doesn't 348 * have boot code -- common on non-i386 hardware. In that 349 * case we check if we have a possible BPB. If so, then we 350 * assume we have a boot sector instead. 351 */ 352 sum = 0; 353 for (index = 0; index < NDOSPART * DOSPARTSIZE; index++) 354 sum += buf[DOSPARTOFF + index]; 355 if (sum != 0 || !mbr_probe_bpb(buf + 0x0b)) 356 res = G_PART_PROBE_PRI_NORM; 357 358 out: 359 g_free(buf); 360 return (res); 361 } 362 363 static int 364 g_part_mbr_read(struct g_part_table *basetable, struct g_consumer *cp) 365 { 366 struct dos_partition ent; 367 struct g_provider *pp; 368 struct g_part_mbr_table *table; 369 struct g_part_mbr_entry *entry; 370 u_char *buf, *p; 371 off_t chs, msize; 372 u_int sectors, heads; 373 int error, index; 374 375 pp = cp->provider; 376 table = (struct g_part_mbr_table *)basetable; 377 msize = pp->mediasize / pp->sectorsize; 378 379 buf = g_read_data(cp, 0L, pp->sectorsize, &error); 380 if (buf == NULL) 381 return (error); 382 383 bcopy(buf, table->mbr, sizeof(table->mbr)); 384 for (index = NDOSPART - 1; index >= 0; index--) { 385 p = buf + DOSPARTOFF + index * DOSPARTSIZE; 386 ent.dp_flag = p[0]; 387 ent.dp_shd = p[1]; 388 ent.dp_ssect = p[2]; 389 ent.dp_scyl = p[3]; 390 ent.dp_typ = p[4]; 391 ent.dp_ehd = p[5]; 392 ent.dp_esect = p[6]; 393 ent.dp_ecyl = p[7]; 394 ent.dp_start = le32dec(p + 8); 395 ent.dp_size = le32dec(p + 12); 396 if (ent.dp_typ == 0 || ent.dp_typ == DOSPTYP_PMBR) 397 continue; 398 if (ent.dp_start == 0 || ent.dp_size == 0) 399 continue; 400 sectors = ent.dp_esect & 0x3f; 401 if (sectors > basetable->gpt_sectors && 402 !basetable->gpt_fixgeom) { 403 g_part_geometry_heads(msize, sectors, &chs, &heads); 404 if (chs != 0) { 405 basetable->gpt_sectors = sectors; 406 basetable->gpt_heads = heads; 407 } 408 } 409 if ((ent.dp_start % basetable->gpt_sectors) != 0) 410 printf("GEOM: %s: partition %d does not start on a " 411 "track boundary.\n", pp->name, index + 1); 412 if ((ent.dp_size % basetable->gpt_sectors) != 0) 413 printf("GEOM: %s: partition %d does not end on a " 414 "track boundary.\n", pp->name, index + 1); 415 416 entry = (struct g_part_mbr_entry *)g_part_new_entry(basetable, 417 index + 1, ent.dp_start, ent.dp_start + ent.dp_size - 1); 418 entry->ent = ent; 419 } 420 421 basetable->gpt_entries = NDOSPART; 422 basetable->gpt_first = basetable->gpt_sectors; 423 basetable->gpt_last = msize - (msize % basetable->gpt_sectors) - 1; 424 425 return (0); 426 } 427 428 static int 429 g_part_mbr_setunset(struct g_part_table *table, struct g_part_entry *baseentry, 430 const char *attrib, unsigned int set) 431 { 432 struct g_part_entry *iter; 433 struct g_part_mbr_entry *entry; 434 int changed; 435 436 if (strcasecmp(attrib, "active") != 0) 437 return (EINVAL); 438 439 /* Only one entry can have the active attribute. */ 440 LIST_FOREACH(iter, &table->gpt_entry, gpe_entry) { 441 if (iter->gpe_deleted) 442 continue; 443 changed = 0; 444 entry = (struct g_part_mbr_entry *)iter; 445 if (iter == baseentry) { 446 if (set && (entry->ent.dp_flag & 0x80) == 0) { 447 entry->ent.dp_flag |= 0x80; 448 changed = 1; 449 } else if (!set && (entry->ent.dp_flag & 0x80)) { 450 entry->ent.dp_flag &= ~0x80; 451 changed = 1; 452 } 453 } else { 454 if (set && (entry->ent.dp_flag & 0x80)) { 455 entry->ent.dp_flag &= ~0x80; 456 changed = 1; 457 } 458 } 459 if (changed && !iter->gpe_created) 460 iter->gpe_modified = 1; 461 } 462 return (0); 463 } 464 465 static const char * 466 g_part_mbr_type(struct g_part_table *basetable, struct g_part_entry *baseentry, 467 char *buf, size_t bufsz) 468 { 469 struct g_part_mbr_entry *entry; 470 int type; 471 472 entry = (struct g_part_mbr_entry *)baseentry; 473 type = entry->ent.dp_typ; 474 if (type == DOSPTYP_386BSD) 475 return (g_part_alias_name(G_PART_ALIAS_FREEBSD)); 476 snprintf(buf, bufsz, "!%d", type); 477 return (buf); 478 } 479 480 static int 481 g_part_mbr_write(struct g_part_table *basetable, struct g_consumer *cp) 482 { 483 struct g_part_entry *baseentry; 484 struct g_part_mbr_entry *entry; 485 struct g_part_mbr_table *table; 486 u_char *p; 487 int error, index; 488 489 table = (struct g_part_mbr_table *)basetable; 490 baseentry = LIST_FIRST(&basetable->gpt_entry); 491 for (index = 1; index <= basetable->gpt_entries; index++) { 492 p = table->mbr + DOSPARTOFF + (index - 1) * DOSPARTSIZE; 493 entry = (baseentry != NULL && index == baseentry->gpe_index) 494 ? (struct g_part_mbr_entry *)baseentry : NULL; 495 if (entry != NULL && !baseentry->gpe_deleted) { 496 p[0] = entry->ent.dp_flag; 497 p[1] = entry->ent.dp_shd; 498 p[2] = entry->ent.dp_ssect; 499 p[3] = entry->ent.dp_scyl; 500 p[4] = entry->ent.dp_typ; 501 p[5] = entry->ent.dp_ehd; 502 p[6] = entry->ent.dp_esect; 503 p[7] = entry->ent.dp_ecyl; 504 le32enc(p + 8, entry->ent.dp_start); 505 le32enc(p + 12, entry->ent.dp_size); 506 } else 507 bzero(p, DOSPARTSIZE); 508 509 if (entry != NULL) 510 baseentry = LIST_NEXT(baseentry, gpe_entry); 511 } 512 513 error = g_write_data(cp, 0, table->mbr, cp->provider->sectorsize); 514 return (error); 515 } 516