1 /*- 2 * Copyright (c) 1994 Bruce D. Evans. 3 * All rights reserved. 4 * 5 * Copyright (c) 1982, 1986, 1988 Regents of the University of California. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 * from: @(#)ufs_disksubr.c 7.16 (Berkeley) 5/4/91 33 * from: ufs_disksubr.c,v 1.8 1994/06/07 01:21:39 phk Exp $ 34 * $FreeBSD: src/sys/kern/subr_diskmbr.c,v 1.45 2000/01/28 10:22:07 bde Exp $ 35 */ 36 37 #include <sys/param.h> 38 #include <sys/systm.h> 39 #include <sys/buf.h> 40 #include <sys/conf.h> 41 #include <sys/diskslice.h> 42 #define DOSPTYP_EXTENDED 5 43 #define DOSPTYP_EXTENDEDX 15 44 #define DOSPTYP_ONTRACK 84 45 #include <sys/diskmbr.h> 46 #include <sys/disk.h> 47 #include <sys/malloc.h> 48 #include <sys/syslog.h> 49 #include <sys/device.h> 50 51 #define TRACE(str) do { if (dsi_debug) kprintf str; } while (0) 52 53 static volatile u_char dsi_debug; 54 55 /* 56 * This is what we have embedded in every boot1 for supporting the bogus 57 * "Dangerously Dedicated" mode. However, the old table is broken because 58 * it has an illegal geometry in it - it specifies 256 heads (heads = end 59 * head + 1) which causes nasty stuff when that wraps to zero in bios code. 60 * eg: divide by zero etc. This caused the dead-thinkpad problem, numerous 61 * SCSI bios crashes, EFI to crash, etc. 62 * 63 * We still have to recognize the old table though, even though we stopped 64 * inflicting it upon the world. 65 */ 66 static struct dos_partition historical_bogus_partition_table[NDOSPART] = { 67 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, }, 68 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, }, 69 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, }, 70 { 0x80, 0, 1, 0, DOSPTYP_386BSD, 255, 255, 255, 0, 50000, }, 71 }; 72 static struct dos_partition historical_bogus_partition_table_fixed[NDOSPART] = { 73 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, }, 74 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, }, 75 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, }, 76 { 0x80, 0, 1, 0, DOSPTYP_386BSD, 254, 255, 255, 0, 50000, }, 77 }; 78 79 static int check_part (char *sname, struct dos_partition *dp, 80 u_int64_t offset, int nsectors, int ntracks, 81 u_int64_t mbr_offset); 82 static void mbr_extended (cdev_t dev, struct disk_info *info, 83 struct diskslices *ssp, u_int64_t ext_offset, 84 u_int64_t ext_size, u_int64_t base_ext_offset, 85 int nsectors, int ntracks, u_int64_t mbr_offset, 86 int level); 87 static int mbr_setslice (char *sname, struct disk_info *info, 88 struct diskslice *sp, struct dos_partition *dp, 89 u_int64_t br_offset); 90 91 92 int 93 mbrinit(cdev_t dev, struct disk_info *info, struct diskslices **sspp) 94 { 95 struct buf *bp; 96 u_char *cp; 97 int dospart; 98 struct dos_partition *dp; 99 struct dos_partition *dp0; 100 struct dos_partition dpcopy[NDOSPART]; 101 int error; 102 int max_ncyls; 103 int max_nsectors; 104 int max_ntracks; 105 u_int64_t mbr_offset; 106 char partname[2]; 107 u_long secpercyl; 108 char *sname = "tempname"; 109 struct diskslice *sp; 110 struct diskslices *ssp; 111 cdev_t wdev; 112 113 mbr_offset = DOSBBSECTOR; 114 reread_mbr: 115 /* 116 * Don't bother if the block size is weird or the 117 * media size is 0 (probably means no media present). 118 */ 119 if (info->d_media_blksize & DEV_BMASK) 120 return (EIO); 121 if (info->d_media_size == 0) 122 return (EIO); 123 124 /* 125 * Read master boot record. 126 */ 127 wdev = dev; 128 bp = geteblk((int)info->d_media_blksize); 129 bp->b_bio1.bio_offset = (off_t)mbr_offset * info->d_media_blksize; 130 bp->b_bio1.bio_done = biodone_sync; 131 bp->b_bio1.bio_flags |= BIO_SYNC; 132 bp->b_bcount = info->d_media_blksize; 133 bp->b_cmd = BUF_CMD_READ; 134 dev_dstrategy(wdev, &bp->b_bio1); 135 if (biowait(&bp->b_bio1, "mbrrd") != 0) { 136 if ((info->d_dsflags & DSO_MBRQUIET) == 0) { 137 diskerr(&bp->b_bio1, wdev, 138 "reading primary partition table: error", 139 LOG_PRINTF, 0); 140 kprintf("\n"); 141 } 142 error = EIO; 143 goto done; 144 } 145 146 /* Weakly verify it. */ 147 cp = bp->b_data; 148 sname = dsname(dev, 0, 0, 0, NULL); 149 if (cp[0x1FE] != 0x55 || cp[0x1FF] != 0xAA) { 150 if (bootverbose) 151 kprintf("%s: invalid primary partition table: no magic\n", 152 sname); 153 error = EINVAL; 154 goto done; 155 } 156 157 /* Make a copy of the partition table to avoid alignment problems. */ 158 memcpy(&dpcopy[0], cp + DOSPARTOFF, sizeof(dpcopy)); 159 160 dp0 = &dpcopy[0]; 161 162 /* 163 * Check for "Ontrack Diskmanager" or GPT. If a GPT is found in 164 * the first dos partition, ignore the rest of the MBR and go 165 * to GPT processing. 166 */ 167 for (dospart = 0, dp = dp0; dospart < NDOSPART; dospart++, dp++) { 168 if (dospart == 0 && 169 (dp->dp_typ == DOSPTYP_PMBR || dp->dp_typ == DOSPTYP_GPT)) { 170 if (bootverbose) 171 kprintf( 172 "%s: Found GPT in slice #%d\n", sname, dospart + 1); 173 error = gptinit(dev, info, sspp); 174 goto done; 175 } 176 177 if (dp->dp_typ == DOSPTYP_ONTRACK) { 178 if (bootverbose) 179 kprintf( 180 "%s: Found \"Ontrack Disk Manager\" on this disk.\n", sname); 181 bp->b_flags |= B_INVAL | B_AGE; 182 brelse(bp); 183 mbr_offset = 63; 184 goto reread_mbr; 185 } 186 } 187 188 if (bcmp(dp0, historical_bogus_partition_table, 189 sizeof historical_bogus_partition_table) == 0 || 190 bcmp(dp0, historical_bogus_partition_table_fixed, 191 sizeof historical_bogus_partition_table_fixed) == 0) { 192 #if 0 193 TRACE(("%s: invalid primary partition table: historical\n", 194 sname)); 195 #endif /* 0 */ 196 if (bootverbose) 197 kprintf( 198 "%s: invalid primary partition table: Dangerously Dedicated (ignored)\n", 199 sname); 200 error = EINVAL; 201 goto done; 202 } 203 204 /* Guess the geometry. */ 205 /* 206 * TODO: 207 * Perhaps skip entries with 0 size. 208 * Perhaps only look at entries of type DOSPTYP_386BSD. 209 */ 210 max_ncyls = 0; 211 max_nsectors = 0; 212 max_ntracks = 0; 213 for (dospart = 0, dp = dp0; dospart < NDOSPART; dospart++, dp++) { 214 int ncyls; 215 int nsectors; 216 int ntracks; 217 218 ncyls = DPCYL(dp->dp_ecyl, dp->dp_esect) + 1; 219 if (max_ncyls < ncyls) 220 max_ncyls = ncyls; 221 nsectors = DPSECT(dp->dp_esect); 222 if (max_nsectors < nsectors) 223 max_nsectors = nsectors; 224 ntracks = dp->dp_ehd + 1; 225 if (max_ntracks < ntracks) 226 max_ntracks = ntracks; 227 } 228 229 /* 230 * Check that we have guessed the geometry right by checking the 231 * partition entries. 232 */ 233 /* 234 * TODO: 235 * As above. 236 * Check for overlaps. 237 * Check against d_secperunit if the latter is reliable. 238 */ 239 error = 0; 240 for (dospart = 0, dp = dp0; dospart < NDOSPART; dospart++, dp++) { 241 if (dp->dp_scyl == 0 && dp->dp_shd == 0 && dp->dp_ssect == 0 242 && dp->dp_start == 0 && dp->dp_size == 0) 243 continue; 244 //sname = dsname(dev, dkunit(dev), BASE_SLICE + dospart, 245 // WHOLE_SLICE_PART, partname); 246 247 /* 248 * Temporarily ignore errors from this check. We could 249 * simplify things by accepting the table eariler if we 250 * always ignore errors here. Perhaps we should always 251 * accept the table if the magic is right but not let 252 * bad entries affect the geometry. 253 */ 254 check_part(sname, dp, mbr_offset, max_nsectors, max_ntracks, 255 mbr_offset); 256 } 257 if (error != 0) 258 goto done; 259 260 /* 261 * Accept the DOS partition table. 262 * 263 * Adjust the disk information structure with updated CHS 264 * conversion parameters, but only use values extracted from 265 * the primary partition table. 266 * 267 * NOTE! Regardless of our having to deal with this old cruft, 268 * we do not screw around with the info->d_media* parameters. 269 */ 270 secpercyl = (u_long)max_nsectors * max_ntracks; 271 if (secpercyl != 0 && mbr_offset == DOSBBSECTOR) { 272 info->d_secpertrack = max_nsectors; 273 info->d_nheads = max_ntracks; 274 info->d_secpercyl = secpercyl; 275 info->d_ncylinders = info->d_media_blocks / secpercyl; 276 } 277 278 /* 279 * We are passed a pointer to a suitably initialized minimal 280 * slices "struct" with no dangling pointers in it. Replace it 281 * by a maximal one. This usually oversizes the "struct", but 282 * enlarging it while searching for logical drives would be 283 * inconvenient. 284 */ 285 kfree(*sspp, M_DEVBUF); 286 ssp = dsmakeslicestruct(MAX_SLICES, info); 287 *sspp = ssp; 288 289 /* Initialize normal slices. */ 290 sp = &ssp->dss_slices[BASE_SLICE]; 291 for (dospart = 0, dp = dp0; dospart < NDOSPART; dospart++, dp++, sp++) { 292 sname = dsname(dev, dkunit(dev), BASE_SLICE + dospart, 293 WHOLE_SLICE_PART, partname); 294 (void)mbr_setslice(sname, info, sp, dp, mbr_offset); 295 } 296 ssp->dss_nslices = BASE_SLICE + NDOSPART; 297 298 /* Handle extended partitions. */ 299 sp -= NDOSPART; 300 for (dospart = 0; dospart < NDOSPART; dospart++, sp++) { 301 if (sp->ds_type == DOSPTYP_EXTENDED || 302 sp->ds_type == DOSPTYP_EXTENDEDX) { 303 mbr_extended(wdev, info, ssp, 304 sp->ds_offset, sp->ds_size, sp->ds_offset, 305 max_nsectors, max_ntracks, mbr_offset, 1); 306 } 307 } 308 309 /* 310 * mbr_extended() abuses ssp->dss_nslices for the number of slices 311 * that would be found if there were no limit on the number of slices 312 * in *ssp. Cut it back now. 313 */ 314 if (ssp->dss_nslices > MAX_SLICES) 315 ssp->dss_nslices = MAX_SLICES; 316 317 done: 318 bp->b_flags |= B_INVAL | B_AGE; 319 brelse(bp); 320 if (error == EINVAL) 321 error = 0; 322 return (error); 323 } 324 325 static int 326 check_part(char *sname, struct dos_partition *dp, u_int64_t offset, 327 int nsectors, int ntracks, u_int64_t mbr_offset) 328 { 329 int chs_ecyl; 330 int chs_esect; 331 int chs_scyl; 332 int chs_ssect; 333 int error; 334 u_long secpercyl; 335 u_int64_t esector; 336 u_int64_t esector1; 337 u_int64_t ssector; 338 u_int64_t ssector1; 339 340 secpercyl = (u_long)nsectors * ntracks; 341 chs_scyl = DPCYL(dp->dp_scyl, dp->dp_ssect); 342 chs_ssect = DPSECT(dp->dp_ssect); 343 ssector = chs_ssect - 1 + dp->dp_shd * nsectors + chs_scyl * secpercyl 344 + mbr_offset; 345 ssector1 = offset + dp->dp_start; 346 347 /* 348 * If ssector1 is on a cylinder >= 1024, then ssector can't be right. 349 * Allow the C/H/S for it to be 1023/ntracks-1/nsectors, or correct 350 * apart from the cylinder being reduced modulo 1024. Always allow 351 * 1023/255/63, because this is the official way to represent 352 * pure-LBA for the starting position. 353 */ 354 if ((ssector < ssector1 355 && ((chs_ssect == nsectors && dp->dp_shd == ntracks - 1 356 && chs_scyl == 1023) 357 || (secpercyl != 0 358 && (ssector1 - ssector) % (1024 * secpercyl) == 0))) 359 || (dp->dp_scyl == 255 && dp->dp_shd == 255 360 && dp->dp_ssect == 255)) { 361 TRACE(("%s: C/H/S start %d/%d/%d, start %llu: allow\n", 362 sname, chs_scyl, dp->dp_shd, chs_ssect, 363 (long long)ssector1)); 364 ssector = ssector1; 365 } 366 367 chs_ecyl = DPCYL(dp->dp_ecyl, dp->dp_esect); 368 chs_esect = DPSECT(dp->dp_esect); 369 esector = chs_esect - 1 + dp->dp_ehd * nsectors + chs_ecyl * secpercyl 370 + mbr_offset; 371 esector1 = ssector1 + dp->dp_size - 1; 372 373 /* 374 * Allow certain bogus C/H/S values for esector, as above. However, 375 * heads == 255 isn't really legal and causes some BIOS crashes. The 376 * correct value to indicate a pure-LBA end is 1023/heads-1/sectors - 377 * usually 1023/254/63. "heads" is base 0, "sectors" is base 1. 378 */ 379 if ((esector < esector1 380 && ((chs_esect == nsectors && dp->dp_ehd == ntracks - 1 381 && chs_ecyl == 1023) 382 || (secpercyl != 0 383 && (esector1 - esector) % (1024 * secpercyl) == 0))) 384 || (dp->dp_ecyl == 255 && dp->dp_ehd == 255 385 && dp->dp_esect == 255)) { 386 TRACE(("%s: C/H/S end %d/%d/%d, end %llu: allow\n", 387 sname, chs_ecyl, dp->dp_ehd, chs_esect, 388 (long long)esector1)); 389 esector = esector1; 390 } 391 392 error = (ssector == ssector1 && esector == esector1) ? 0 : EINVAL; 393 if (bootverbose) 394 kprintf("%s: type 0x%x, start %llu, end = %llu, size %u %s\n", 395 sname, dp->dp_typ, 396 (long long)ssector1, (long long)esector1, 397 dp->dp_size, (error ? "" : ": OK")); 398 if (ssector != ssector1 && bootverbose) 399 kprintf("%s: C/H/S start %d/%d/%d (%llu) != start %llu: invalid\n", 400 sname, chs_scyl, dp->dp_shd, chs_ssect, 401 (long long)ssector, (long long)ssector1); 402 if (esector != esector1 && bootverbose) 403 kprintf("%s: C/H/S end %d/%d/%d (%llu) != end %llu: invalid\n", 404 sname, chs_ecyl, dp->dp_ehd, chs_esect, 405 (long long)esector, (long long)esector1); 406 return (error); 407 } 408 409 static 410 void 411 mbr_extended(cdev_t dev, struct disk_info *info, struct diskslices *ssp, 412 u_int64_t ext_offset, u_int64_t ext_size, u_int64_t base_ext_offset, 413 int nsectors, int ntracks, u_int64_t mbr_offset, int level) 414 { 415 struct buf *bp; 416 u_char *cp; 417 int dospart; 418 struct dos_partition *dp; 419 struct dos_partition dpcopy[NDOSPART]; 420 u_int64_t ext_offsets[NDOSPART]; 421 u_int64_t ext_sizes[NDOSPART]; 422 char partname[2]; 423 int slice; 424 char *sname; 425 struct diskslice *sp; 426 427 if (level >= 16) { 428 kprintf( 429 "%s: excessive recursion in search for slices; aborting search\n", 430 devtoname(dev)); 431 return; 432 } 433 434 /* Read extended boot record. */ 435 bp = geteblk((int)info->d_media_blksize); 436 bp->b_bio1.bio_offset = (off_t)ext_offset * info->d_media_blksize; 437 bp->b_bio1.bio_done = biodone_sync; 438 bp->b_bio1.bio_flags |= BIO_SYNC; 439 bp->b_bcount = info->d_media_blksize; 440 bp->b_cmd = BUF_CMD_READ; 441 dev_dstrategy(dev, &bp->b_bio1); 442 if (biowait(&bp->b_bio1, "mbrrd") != 0) { 443 diskerr(&bp->b_bio1, dev, 444 "reading extended partition table: error", 445 LOG_PRINTF, 0); 446 kprintf("\n"); 447 goto done; 448 } 449 450 /* Weakly verify it. */ 451 cp = bp->b_data; 452 if (cp[0x1FE] != 0x55 || cp[0x1FF] != 0xAA) { 453 sname = dsname(dev, dkunit(dev), WHOLE_DISK_SLICE, WHOLE_SLICE_PART, 454 partname); 455 if (bootverbose) 456 kprintf("%s: invalid extended partition table: no magic\n", 457 sname); 458 goto done; 459 } 460 461 /* Make a copy of the partition table to avoid alignment problems. */ 462 memcpy(&dpcopy[0], cp + DOSPARTOFF, sizeof(dpcopy)); 463 464 slice = ssp->dss_nslices; 465 for (dospart = 0, dp = &dpcopy[0]; dospart < NDOSPART; 466 dospart++, dp++) { 467 ext_sizes[dospart] = 0; 468 if (dp->dp_scyl == 0 && dp->dp_shd == 0 && dp->dp_ssect == 0 469 && dp->dp_start == 0 && dp->dp_size == 0) 470 continue; 471 if (dp->dp_typ == DOSPTYP_EXTENDED || 472 dp->dp_typ == DOSPTYP_EXTENDEDX) { 473 static char buf[32]; 474 475 sname = dsname(dev, dkunit(dev), WHOLE_DISK_SLICE, 476 WHOLE_SLICE_PART, partname); 477 ksnprintf(buf, sizeof(buf), "%s", sname); 478 if (strlen(buf) < sizeof buf - 11) 479 strcat(buf, "<extended>"); 480 check_part(buf, dp, base_ext_offset, nsectors, 481 ntracks, mbr_offset); 482 ext_offsets[dospart] = base_ext_offset + dp->dp_start; 483 ext_sizes[dospart] = dp->dp_size; 484 } else { 485 sname = dsname(dev, dkunit(dev), slice, WHOLE_SLICE_PART, 486 partname); 487 check_part(sname, dp, ext_offset, nsectors, ntracks, 488 mbr_offset); 489 if (slice >= MAX_SLICES) { 490 kprintf("%s: too many slices\n", sname); 491 slice++; 492 continue; 493 } 494 sp = &ssp->dss_slices[slice]; 495 if (mbr_setslice(sname, info, sp, dp, ext_offset) != 0) 496 continue; 497 slice++; 498 } 499 } 500 ssp->dss_nslices = slice; 501 502 /* If we found any more slices, recursively find all the subslices. */ 503 for (dospart = 0; dospart < NDOSPART; dospart++) { 504 if (ext_sizes[dospart] != 0) { 505 mbr_extended(dev, info, ssp, ext_offsets[dospart], 506 ext_sizes[dospart], base_ext_offset, 507 nsectors, ntracks, mbr_offset, ++level); 508 } 509 } 510 511 done: 512 bp->b_flags |= B_INVAL | B_AGE; 513 brelse(bp); 514 } 515 516 static int 517 mbr_setslice(char *sname, struct disk_info *info, struct diskslice *sp, 518 struct dos_partition *dp, u_int64_t br_offset) 519 { 520 u_int64_t offset; 521 u_int64_t size; 522 523 offset = br_offset + dp->dp_start; 524 if (offset > info->d_media_blocks || offset < br_offset) { 525 kprintf( 526 "%s: slice starts beyond end of the disk: rejecting it\n", 527 sname); 528 return (1); 529 } 530 size = info->d_media_blocks - offset; 531 if (size >= dp->dp_size) { 532 if (dp->dp_size == 0xFFFFFFFFU) { 533 kprintf("%s: slice >2TB, using media size instead " 534 "of slice table size\n", sname); 535 } else { 536 size = dp->dp_size; 537 } 538 } else { 539 kprintf("%s: slice extends beyond end of disk: " 540 "truncating from %u to %llu sectors\n", 541 sname, dp->dp_size, (unsigned long long)size); 542 } 543 sp->ds_offset = offset; 544 sp->ds_size = size; 545 sp->ds_type = dp->dp_typ; 546 bzero(&sp->ds_type_uuid, sizeof(sp->ds_type_uuid)); 547 bzero(&sp->ds_stor_uuid, sizeof(sp->ds_type_uuid)); 548 549 /* 550 * Slices do not overlap with the parent (if any). 551 */ 552 sp->ds_reserved = 0; 553 return (0); 554 } 555