1 /* 2 * GRUB -- GRand Unified Bootloader 3 * Copyright (C) 1999,2000,2001,2002,2003,2004 Free Software Foundation, Inc. 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License as published by 7 * the Free Software Foundation; either version 2 of the License, or 8 * (at your option) any later version. 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program; if not, write to the Free Software 17 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 18 */ 19 /* 20 * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 21 * Use is subject to license terms. 22 */ 23 #pragma ident "%Z%%M% %I% %E% SMI" 24 25 /* 26 * The zfs plug-in routines for GRUB are: 27 * 28 * zfs_mount() - locates a valid uberblock of the root pool and reads 29 * in its MOS at the memory address MOS. 30 * 31 * zfs_open() - locates a plain file object by following the MOS 32 * and places its dnode at the memory address DNODE. 33 * 34 * zfs_read() - read in the data blocks pointed by the DNODE. 35 * 36 * ZFS_SCRATCH is used as a working area. 37 * 38 * (memory addr) MOS DNODE ZFS_SCRATCH 39 * | | | 40 * +-------V---------V----------V---------------+ 41 * memory | | dnode | dnode | scratch | 42 * | | 512B | 512B | area | 43 * +--------------------------------------------+ 44 */ 45 46 #ifdef FSYS_ZFS 47 48 #include "shared.h" 49 #include "filesys.h" 50 #include "fsys_zfs.h" 51 52 /* cache for a file block of the currently zfs_open()-ed file */ 53 static void *file_buf = NULL; 54 static uint64_t file_start = 0; 55 static uint64_t file_end = 0; 56 57 /* cache for a dnode block */ 58 static dnode_phys_t *dnode_buf = NULL; 59 static dnode_phys_t *dnode_mdn = NULL; 60 static uint64_t dnode_start = 0; 61 static uint64_t dnode_end = 0; 62 63 static char *stackbase; 64 65 decomp_entry_t decomp_table[ZIO_COMPRESS_FUNCTIONS] = 66 { 67 {"noop", 0}, 68 {"on", lzjb_decompress}, /* ZIO_COMPRESS_ON */ 69 {"off", 0}, 70 {"lzjb", lzjb_decompress} /* ZIO_COMPRESS_LZJB */ 71 }; 72 73 /* 74 * Our own version of bcmp(). 75 */ 76 static int 77 zfs_bcmp(const void *s1, const void *s2, size_t n) 78 { 79 const uchar_t *ps1 = s1; 80 const uchar_t *ps2 = s2; 81 82 if (s1 != s2 && n != 0) { 83 do { 84 if (*ps1++ != *ps2++) 85 return (1); 86 } while (--n != 0); 87 } 88 89 return (0); 90 } 91 92 /* 93 * Our own version of log2(). Same thing as highbit()-1. 94 */ 95 static int 96 zfs_log2(uint64_t num) 97 { 98 int i = 0; 99 100 while (num > 1) { 101 i++; 102 num = num >> 1; 103 } 104 105 return (i); 106 } 107 108 /* Checksum Functions */ 109 static void 110 zio_checksum_off(const void *buf, uint64_t size, zio_cksum_t *zcp) 111 { 112 ZIO_SET_CHECKSUM(zcp, 0, 0, 0, 0); 113 } 114 115 /* Checksum Table and Values */ 116 zio_checksum_info_t zio_checksum_table[ZIO_CHECKSUM_FUNCTIONS] = { 117 NULL, NULL, 0, 0, "inherit", 118 NULL, NULL, 0, 0, "on", 119 zio_checksum_off, zio_checksum_off, 0, 0, "off", 120 zio_checksum_SHA256, zio_checksum_SHA256, 1, 1, "label", 121 zio_checksum_SHA256, zio_checksum_SHA256, 1, 1, "gang_header", 122 fletcher_2_native, fletcher_2_byteswap, 0, 1, "zilog", 123 fletcher_2_native, fletcher_2_byteswap, 0, 0, "fletcher2", 124 fletcher_4_native, fletcher_4_byteswap, 1, 0, "fletcher4", 125 zio_checksum_SHA256, zio_checksum_SHA256, 1, 0, "SHA256", 126 }; 127 128 /* 129 * zio_checksum_verify: Provides support for checksum verification. 130 * 131 * Fletcher2, Fletcher4, and SHA256 are supported. 132 * 133 * Return: 134 * -1 = Failure 135 * 0 = Success 136 */ 137 static int 138 zio_checksum_verify(blkptr_t *bp, char *data, int size) 139 { 140 zio_cksum_t zc = bp->blk_cksum; 141 uint32_t checksum = BP_IS_GANG(bp) ? ZIO_CHECKSUM_GANG_HEADER : 142 BP_GET_CHECKSUM(bp); 143 int byteswap = BP_SHOULD_BYTESWAP(bp); 144 zio_block_tail_t *zbt = (zio_block_tail_t *)(data + size) - 1; 145 zio_checksum_info_t *ci = &zio_checksum_table[checksum]; 146 zio_cksum_t actual_cksum, expected_cksum; 147 148 /* byteswap is not supported */ 149 if (byteswap) 150 return (-1); 151 152 if (checksum >= ZIO_CHECKSUM_FUNCTIONS || ci->ci_func[0] == NULL) 153 return (-1); 154 155 if (ci->ci_zbt) { 156 if (checksum == ZIO_CHECKSUM_GANG_HEADER) { 157 /* 158 * 'gang blocks' is not supported. 159 */ 160 return (-1); 161 } 162 163 if (zbt->zbt_magic == BSWAP_64(ZBT_MAGIC)) { 164 /* byte swapping is not supported */ 165 return (-1); 166 } else { 167 expected_cksum = zbt->zbt_cksum; 168 zbt->zbt_cksum = zc; 169 ci->ci_func[0](data, size, &actual_cksum); 170 zbt->zbt_cksum = expected_cksum; 171 } 172 zc = expected_cksum; 173 174 } else { 175 if (BP_IS_GANG(bp)) 176 return (-1); 177 ci->ci_func[byteswap](data, size, &actual_cksum); 178 } 179 180 if ((actual_cksum.zc_word[0] - zc.zc_word[0]) | 181 (actual_cksum.zc_word[1] - zc.zc_word[1]) | 182 (actual_cksum.zc_word[2] - zc.zc_word[2]) | 183 (actual_cksum.zc_word[3] - zc.zc_word[3])) 184 return (-1); 185 186 return (0); 187 } 188 189 /* 190 * vdev_label_offset takes "offset" (the offset within a vdev_label) and 191 * returns its physical disk offset (starting from the beginning of the vdev). 192 * 193 * Input: 194 * psize : Physical size of this vdev 195 * l : Label Number (0-3) 196 * offset : The offset with a vdev_label in which we want the physical 197 * address 198 * Return: 199 * Success : physical disk offset 200 * Failure : errnum = ERR_BAD_ARGUMENT, return value is meaningless 201 */ 202 static uint64_t 203 vdev_label_offset(uint64_t psize, int l, uint64_t offset) 204 { 205 /* XXX Need to add back label support! */ 206 if (l >= VDEV_LABELS/2 || offset > sizeof (vdev_label_t)) { 207 errnum = ERR_BAD_ARGUMENT; 208 return (0); 209 } 210 211 return (offset + l * sizeof (vdev_label_t) + (l < VDEV_LABELS / 2 ? 212 0 : psize - VDEV_LABELS * sizeof (vdev_label_t))); 213 214 } 215 216 /* 217 * vdev_uberblock_compare takes two uberblock structures and returns an integer 218 * indicating the more recent of the two. 219 * Return Value = 1 if ub2 is more recent 220 * Return Value = -1 if ub1 is more recent 221 * The most recent uberblock is determined using its transaction number and 222 * timestamp. The uberblock with the highest transaction number is 223 * considered "newer". If the transaction numbers of the two blocks match, the 224 * timestamps are compared to determine the "newer" of the two. 225 */ 226 static int 227 vdev_uberblock_compare(uberblock_t *ub1, uberblock_t *ub2) 228 { 229 if (ub1->ub_txg < ub2->ub_txg) 230 return (-1); 231 if (ub1->ub_txg > ub2->ub_txg) 232 return (1); 233 234 if (ub1->ub_timestamp < ub2->ub_timestamp) 235 return (-1); 236 if (ub1->ub_timestamp > ub2->ub_timestamp) 237 return (1); 238 239 return (0); 240 } 241 242 /* 243 * Three pieces of information are needed to verify an uberblock: the magic 244 * number, the version number, and the checksum. 245 * 246 * Currently Implemented: version number, magic number 247 * Need to Implement: checksum 248 * 249 * Return: 250 * 0 - Success 251 * -1 - Failure 252 */ 253 static int 254 uberblock_verify(uberblock_phys_t *ub, int offset) 255 { 256 257 uberblock_t *uber = &ub->ubp_uberblock; 258 blkptr_t bp; 259 260 BP_ZERO(&bp); 261 BP_SET_CHECKSUM(&bp, ZIO_CHECKSUM_LABEL); 262 BP_SET_BYTEORDER(&bp, ZFS_HOST_BYTEORDER); 263 ZIO_SET_CHECKSUM(&bp.blk_cksum, offset, 0, 0, 0); 264 265 if (zio_checksum_verify(&bp, (char *)ub, UBERBLOCK_SIZE) != 0) 266 return (-1); 267 268 if (uber->ub_magic == UBERBLOCK_MAGIC && 269 uber->ub_version >= SPA_VERSION_1 && 270 uber->ub_version <= SPA_VERSION) 271 return (0); 272 273 return (-1); 274 } 275 276 /* 277 * Find the best uberblock. 278 * Return: 279 * Success - Pointer to the best uberblock. 280 * Failure - NULL 281 */ 282 static uberblock_phys_t * 283 find_bestub(uberblock_phys_t *ub_array, int label) 284 { 285 uberblock_phys_t *ubbest = NULL; 286 int i, offset; 287 288 for (i = 0; i < (VDEV_UBERBLOCK_RING >> VDEV_UBERBLOCK_SHIFT); i++) { 289 offset = vdev_label_offset(0, label, VDEV_UBERBLOCK_OFFSET(i)); 290 if (errnum == ERR_BAD_ARGUMENT) 291 return (NULL); 292 if (uberblock_verify(&ub_array[i], offset) == 0) { 293 if (ubbest == NULL) { 294 ubbest = &ub_array[i]; 295 } else if (vdev_uberblock_compare( 296 &(ub_array[i].ubp_uberblock), 297 &(ubbest->ubp_uberblock)) > 0) { 298 ubbest = &ub_array[i]; 299 } 300 } 301 } 302 303 return (ubbest); 304 } 305 306 /* 307 * Read in a block and put its uncompressed data in buf. 308 * 309 * Return: 310 * 0 - success 311 * errnum - failure 312 */ 313 static int 314 zio_read(blkptr_t *bp, void *buf, char *stack) 315 { 316 uint64_t offset, sector; 317 int psize, lsize; 318 int i, comp, cksum; 319 320 psize = BP_GET_PSIZE(bp); 321 lsize = BP_GET_LSIZE(bp); 322 comp = BP_GET_COMPRESS(bp); 323 cksum = BP_GET_CHECKSUM(bp); 324 325 if ((unsigned int)comp >= ZIO_COMPRESS_FUNCTIONS || 326 comp != ZIO_COMPRESS_OFF && decomp_table[comp].decomp_func == NULL) 327 return (ERR_FSYS_CORRUPT); 328 329 /* pick a good dva from the block pointer */ 330 for (i = 0; i < SPA_DVAS_PER_BP; i++) { 331 332 if (bp->blk_dva[i].dva_word[0] == 0 && 333 bp->blk_dva[i].dva_word[1] == 0) 334 continue; 335 336 /* read in a block */ 337 offset = DVA_GET_OFFSET(&bp->blk_dva[i]); 338 sector = DVA_OFFSET_TO_PHYS_SECTOR(offset); 339 340 if (comp != ZIO_COMPRESS_OFF) { 341 342 if (devread(sector, 0, psize, stack) == 0) 343 continue; 344 if (zio_checksum_verify(bp, stack, psize) != 0) 345 continue; 346 decomp_table[comp].decomp_func(stack, buf, psize, 347 lsize); 348 } else { 349 if (devread(sector, 0, psize, buf) == 0) 350 continue; 351 if (zio_checksum_verify(bp, buf, psize) != 0) 352 continue; 353 } 354 return (0); 355 } 356 357 return (ERR_FSYS_CORRUPT); 358 } 359 360 /* 361 * Get the block from a block id. 362 * push the block onto the stack. 363 * 364 * Return: 365 * 0 - success 366 * errnum - failure 367 */ 368 static int 369 dmu_read(dnode_phys_t *dn, uint64_t blkid, void *buf, char *stack) 370 { 371 int idx, level; 372 blkptr_t *bp_array = dn->dn_blkptr; 373 int epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 374 blkptr_t *bp, *tmpbuf; 375 376 bp = (blkptr_t *)stack; 377 stack += sizeof (blkptr_t); 378 379 tmpbuf = (blkptr_t *)stack; 380 stack += 1<<dn->dn_indblkshift; 381 382 for (level = dn->dn_nlevels - 1; level >= 0; level--) { 383 idx = (blkid >> (epbs * level)) & ((1<<epbs)-1); 384 *bp = bp_array[idx]; 385 if (level == 0) 386 tmpbuf = buf; 387 if (BP_IS_HOLE(bp)) { 388 grub_memset(buf, 0, 389 dn->dn_datablkszsec << SPA_MINBLOCKSHIFT); 390 break; 391 } else if (errnum = zio_read(bp, tmpbuf, stack)) { 392 return (errnum); 393 } 394 395 bp_array = tmpbuf; 396 } 397 398 return (0); 399 } 400 401 /* 402 * mzap_lookup: Looks up property described by "name" and returns the value 403 * in "value". 404 * 405 * Return: 406 * 0 - success 407 * errnum - failure 408 */ 409 static int 410 mzap_lookup(mzap_phys_t *zapobj, int objsize, char *name, 411 uint64_t *value) 412 { 413 int i, chunks; 414 mzap_ent_phys_t *mzap_ent = zapobj->mz_chunk; 415 416 chunks = objsize/MZAP_ENT_LEN - 1; 417 for (i = 0; i < chunks; i++) { 418 if (grub_strcmp(mzap_ent[i].mze_name, name) == 0) { 419 *value = mzap_ent[i].mze_value; 420 return (0); 421 } 422 } 423 424 return (ERR_FSYS_CORRUPT); 425 } 426 427 static uint64_t 428 zap_hash(uint64_t salt, const char *name) 429 { 430 static uint64_t table[256]; 431 const uint8_t *cp; 432 uint8_t c; 433 uint64_t crc = salt; 434 435 if (table[128] == 0) { 436 uint64_t *ct; 437 int i, j; 438 for (i = 0; i < 256; i++) { 439 for (ct = table + i, *ct = i, j = 8; j > 0; j--) 440 *ct = (*ct >> 1) ^ (-(*ct & 1) & 441 ZFS_CRC64_POLY); 442 } 443 } 444 445 if (crc == 0 || table[128] != ZFS_CRC64_POLY) { 446 errnum = ERR_FSYS_CORRUPT; 447 return (0); 448 } 449 450 for (cp = (const uint8_t *)name; (c = *cp) != '\0'; cp++) 451 crc = (crc >> 8) ^ table[(crc ^ c) & 0xFF]; 452 453 /* 454 * Only use 28 bits, since we need 4 bits in the cookie for the 455 * collision differentiator. We MUST use the high bits, since 456 * those are the onces that we first pay attention to when 457 * chosing the bucket. 458 */ 459 crc &= ~((1ULL << (64 - ZAP_HASHBITS)) - 1); 460 461 return (crc); 462 } 463 464 /* 465 * Only to be used on 8-bit arrays. 466 * array_len is actual len in bytes (not encoded le_value_length). 467 * buf is null-terminated. 468 */ 469 static int 470 zap_leaf_array_equal(zap_leaf_phys_t *l, int blksft, int chunk, 471 int array_len, const char *buf) 472 { 473 int bseen = 0; 474 475 while (bseen < array_len) { 476 struct zap_leaf_array *la = 477 &ZAP_LEAF_CHUNK(l, blksft, chunk).l_array; 478 int toread = MIN(array_len - bseen, ZAP_LEAF_ARRAY_BYTES); 479 480 if (chunk >= ZAP_LEAF_NUMCHUNKS(blksft)) 481 return (0); 482 483 if (zfs_bcmp(la->la_array, buf + bseen, toread) != 0) 484 break; 485 chunk = la->la_next; 486 bseen += toread; 487 } 488 return (bseen == array_len); 489 } 490 491 /* 492 * Given a zap_leaf_phys_t, walk thru the zap leaf chunks to get the 493 * value for the property "name". 494 * 495 * Return: 496 * 0 - success 497 * errnum - failure 498 */ 499 static int 500 zap_leaf_lookup(zap_leaf_phys_t *l, int blksft, uint64_t h, 501 const char *name, uint64_t *value) 502 { 503 uint16_t chunk; 504 struct zap_leaf_entry *le; 505 506 /* Verify if this is a valid leaf block */ 507 if (l->l_hdr.lh_block_type != ZBT_LEAF) 508 return (ERR_FSYS_CORRUPT); 509 if (l->l_hdr.lh_magic != ZAP_LEAF_MAGIC) 510 return (ERR_FSYS_CORRUPT); 511 512 for (chunk = l->l_hash[LEAF_HASH(blksft, h)]; 513 chunk != CHAIN_END; chunk = le->le_next) { 514 515 if (chunk >= ZAP_LEAF_NUMCHUNKS(blksft)) 516 return (ERR_FSYS_CORRUPT); 517 518 le = ZAP_LEAF_ENTRY(l, blksft, chunk); 519 520 /* Verify the chunk entry */ 521 if (le->le_type != ZAP_CHUNK_ENTRY) 522 return (ERR_FSYS_CORRUPT); 523 524 if (le->le_hash != h) 525 continue; 526 527 if (zap_leaf_array_equal(l, blksft, le->le_name_chunk, 528 le->le_name_length, name)) { 529 530 struct zap_leaf_array *la; 531 uint8_t *ip; 532 533 if (le->le_int_size != 8 || le->le_value_length != 1) 534 return (ERR_FSYS_CORRUPT); 535 536 /* get the uint64_t property value */ 537 la = &ZAP_LEAF_CHUNK(l, blksft, 538 le->le_value_chunk).l_array; 539 ip = la->la_array; 540 541 *value = (uint64_t)ip[0] << 56 | (uint64_t)ip[1] << 48 | 542 (uint64_t)ip[2] << 40 | (uint64_t)ip[3] << 32 | 543 (uint64_t)ip[4] << 24 | (uint64_t)ip[5] << 16 | 544 (uint64_t)ip[6] << 8 | (uint64_t)ip[7]; 545 546 return (0); 547 } 548 } 549 550 return (ERR_FSYS_CORRUPT); 551 } 552 553 /* 554 * Fat ZAP lookup 555 * 556 * Return: 557 * 0 - success 558 * errnum - failure 559 */ 560 static int 561 fzap_lookup(dnode_phys_t *zap_dnode, zap_phys_t *zap, 562 char *name, uint64_t *value, char *stack) 563 { 564 zap_leaf_phys_t *l; 565 uint64_t hash, idx, blkid; 566 int blksft = zfs_log2(zap_dnode->dn_datablkszsec << DNODE_SHIFT); 567 568 /* Verify if this is a fat zap header block */ 569 if (zap->zap_magic != (uint64_t)ZAP_MAGIC) 570 return (ERR_FSYS_CORRUPT); 571 572 hash = zap_hash(zap->zap_salt, name); 573 if (errnum) 574 return (errnum); 575 576 /* get block id from index */ 577 if (zap->zap_ptrtbl.zt_numblks != 0) { 578 /* external pointer tables not supported */ 579 return (ERR_FSYS_CORRUPT); 580 } 581 idx = ZAP_HASH_IDX(hash, zap->zap_ptrtbl.zt_shift); 582 blkid = ((uint64_t *)zap)[idx + (1<<(blksft-3-1))]; 583 584 /* Get the leaf block */ 585 l = (zap_leaf_phys_t *)stack; 586 stack += 1<<blksft; 587 if (errnum = dmu_read(zap_dnode, blkid, l, stack)) 588 return (errnum); 589 590 return (zap_leaf_lookup(l, blksft, hash, name, value)); 591 } 592 593 /* 594 * Read in the data of a zap object and find the value for a matching 595 * property name. 596 * 597 * Return: 598 * 0 - success 599 * errnum - failure 600 */ 601 static int 602 zap_lookup(dnode_phys_t *zap_dnode, char *name, uint64_t *val, char *stack) 603 { 604 uint64_t block_type; 605 int size; 606 void *zapbuf; 607 608 /* Read in the first block of the zap object data. */ 609 zapbuf = stack; 610 size = zap_dnode->dn_datablkszsec << SPA_MINBLOCKSHIFT; 611 stack += size; 612 if (errnum = dmu_read(zap_dnode, 0, zapbuf, stack)) 613 return (errnum); 614 615 block_type = *((uint64_t *)zapbuf); 616 617 if (block_type == ZBT_MICRO) { 618 return (mzap_lookup(zapbuf, size, name, val)); 619 } else if (block_type == ZBT_HEADER) { 620 /* this is a fat zap */ 621 return (fzap_lookup(zap_dnode, zapbuf, name, 622 val, stack)); 623 } 624 625 return (ERR_FSYS_CORRUPT); 626 } 627 628 /* 629 * Get the dnode of an object number from the metadnode of an object set. 630 * 631 * Input 632 * mdn - metadnode to get the object dnode 633 * objnum - object number for the object dnode 634 * buf - data buffer that holds the returning dnode 635 * stack - scratch area 636 * 637 * Return: 638 * 0 - success 639 * errnum - failure 640 */ 641 static int 642 dnode_get(dnode_phys_t *mdn, uint64_t objnum, uint8_t type, dnode_phys_t *buf, 643 char *stack) 644 { 645 uint64_t blkid, blksz; /* the block id this object dnode is in */ 646 int epbs; /* shift of number of dnodes in a block */ 647 int idx; /* index within a block */ 648 dnode_phys_t *dnbuf; 649 650 blksz = mdn->dn_datablkszsec << SPA_MINBLOCKSHIFT; 651 epbs = zfs_log2(blksz) - DNODE_SHIFT; 652 blkid = objnum >> epbs; 653 idx = objnum & ((1<<epbs)-1); 654 655 if (dnode_buf != NULL && dnode_mdn == mdn && 656 objnum >= dnode_start && objnum < dnode_end) { 657 grub_memmove(buf, &dnode_buf[idx], DNODE_SIZE); 658 VERIFY_DN_TYPE(buf, type); 659 return (0); 660 } 661 662 if (dnode_buf && blksz == 1<<DNODE_BLOCK_SHIFT) { 663 dnbuf = dnode_buf; 664 dnode_mdn = mdn; 665 dnode_start = blkid << epbs; 666 dnode_end = (blkid + 1) << epbs; 667 } else { 668 dnbuf = (dnode_phys_t *)stack; 669 stack += blksz; 670 } 671 672 if (errnum = dmu_read(mdn, blkid, (char *)dnbuf, stack)) 673 return (errnum); 674 675 grub_memmove(buf, &dnbuf[idx], DNODE_SIZE); 676 VERIFY_DN_TYPE(buf, type); 677 678 return (0); 679 } 680 681 /* 682 * Check if this is a special file that resides at the top 683 * dataset of the pool. Currently this is the GRUB menu, 684 * boot signature and boot signature backup. 685 * str starts with '/'. 686 */ 687 static int 688 is_top_dataset_file(char *str) 689 { 690 char *tptr; 691 692 if ((tptr = grub_strstr(str, "menu.lst")) && 693 (tptr[8] == '\0' || tptr[8] == ' ') && 694 *(tptr-1) == '/') 695 return (1); 696 697 if (grub_strncmp(str, BOOTSIGN_DIR"/", 698 grub_strlen(BOOTSIGN_DIR) + 1) == 0) 699 return (1); 700 701 if (grub_strcmp(str, BOOTSIGN_BACKUP) == 0) 702 return (1); 703 704 return (0); 705 } 706 707 /* 708 * Get the file dnode for a given file name where mdn is the meta dnode 709 * for this ZFS object set. When found, place the file dnode in dn. 710 * The 'path' argument will be mangled. 711 * 712 * Return: 713 * 0 - success 714 * errnum - failure 715 */ 716 static int 717 dnode_get_path(dnode_phys_t *mdn, char *path, dnode_phys_t *dn, 718 char *stack) 719 { 720 uint64_t objnum, version; 721 char *cname, ch; 722 723 if (errnum = dnode_get(mdn, MASTER_NODE_OBJ, DMU_OT_MASTER_NODE, 724 dn, stack)) 725 return (errnum); 726 727 if (errnum = zap_lookup(dn, ZPL_VERSION_STR, &version, stack)) 728 return (errnum); 729 if (version > ZPL_VERSION) 730 return (-1); 731 732 if (errnum = zap_lookup(dn, ZFS_ROOT_OBJ, &objnum, stack)) 733 return (errnum); 734 735 if (errnum = dnode_get(mdn, objnum, DMU_OT_DIRECTORY_CONTENTS, 736 dn, stack)) 737 return (errnum); 738 739 /* skip leading slashes */ 740 while (*path == '/') 741 path++; 742 743 while (*path && !isspace(*path)) { 744 745 /* get the next component name */ 746 cname = path; 747 while (*path && !isspace(*path) && *path != '/') 748 path++; 749 ch = *path; 750 *path = 0; /* ensure null termination */ 751 752 if (errnum = zap_lookup(dn, cname, &objnum, stack)) 753 return (errnum); 754 755 objnum = ZFS_DIRENT_OBJ(objnum); 756 if (errnum = dnode_get(mdn, objnum, 0, dn, stack)) 757 return (errnum); 758 759 *path = ch; 760 while (*path == '/') 761 path++; 762 } 763 764 /* We found the dnode for this file. Verify if it is a plain file. */ 765 VERIFY_DN_TYPE(dn, DMU_OT_PLAIN_FILE_CONTENTS); 766 767 return (0); 768 } 769 770 /* 771 * Get the default 'bootfs' property value from the rootpool. 772 * 773 * Return: 774 * 0 - success 775 * errnum -failure 776 */ 777 static int 778 get_default_bootfsobj(dnode_phys_t *mosmdn, uint64_t *obj, char *stack) 779 { 780 uint64_t objnum = 0; 781 dnode_phys_t *dn = (dnode_phys_t *)stack; 782 stack += DNODE_SIZE; 783 784 if (errnum = dnode_get(mosmdn, DMU_POOL_DIRECTORY_OBJECT, 785 DMU_OT_OBJECT_DIRECTORY, dn, stack)) 786 return (errnum); 787 788 /* 789 * find the object number for 'pool_props', and get the dnode 790 * of the 'pool_props'. 791 */ 792 if (zap_lookup(dn, DMU_POOL_PROPS, &objnum, stack)) 793 return (ERR_FILESYSTEM_NOT_FOUND); 794 795 if (errnum = dnode_get(mosmdn, objnum, DMU_OT_POOL_PROPS, dn, stack)) 796 return (errnum); 797 798 if (zap_lookup(dn, ZPOOL_PROP_BOOTFS, &objnum, stack)) 799 return (ERR_FILESYSTEM_NOT_FOUND); 800 801 if (!objnum) 802 return (ERR_FILESYSTEM_NOT_FOUND); 803 804 *obj = objnum; 805 return (0); 806 } 807 808 /* 809 * Given a MOS metadnode, get the metadnode of a given filesystem name (fsname), 810 * e.g. pool/rootfs, or a given object number (obj), e.g. the object number 811 * of pool/rootfs. 812 * 813 * If no fsname and no obj are given, return the DSL_DIR metadnode. 814 * If fsname is given, return its metadnode and its matching object number. 815 * If only obj is given, return the metadnode for this object number. 816 * 817 * Return: 818 * 0 - success 819 * errnum - failure 820 */ 821 static int 822 get_objset_mdn(dnode_phys_t *mosmdn, char *fsname, uint64_t *obj, 823 dnode_phys_t *mdn, char *stack) 824 { 825 uint64_t objnum, headobj; 826 char *cname, ch; 827 blkptr_t *bp; 828 objset_phys_t *osp; 829 830 if (fsname == NULL && obj) { 831 headobj = *obj; 832 goto skip; 833 } 834 835 if (errnum = dnode_get(mosmdn, DMU_POOL_DIRECTORY_OBJECT, 836 DMU_OT_OBJECT_DIRECTORY, mdn, stack)) 837 return (errnum); 838 839 if (errnum = zap_lookup(mdn, DMU_POOL_ROOT_DATASET, &objnum, 840 stack)) 841 return (errnum); 842 843 if (errnum = dnode_get(mosmdn, objnum, DMU_OT_DSL_DIR, mdn, stack)) 844 return (errnum); 845 846 if (fsname == NULL) { 847 headobj = 848 ((dsl_dir_phys_t *)DN_BONUS(mdn))->dd_head_dataset_obj; 849 goto skip; 850 } 851 852 /* take out the pool name */ 853 while (*fsname && !isspace(*fsname) && *fsname != '/') 854 fsname++; 855 856 while (*fsname && !isspace(*fsname)) { 857 uint64_t childobj; 858 859 while (*fsname == '/') 860 fsname++; 861 862 cname = fsname; 863 while (*fsname && !isspace(*fsname) && *fsname != '/') 864 fsname++; 865 ch = *fsname; 866 *fsname = 0; 867 868 childobj = 869 ((dsl_dir_phys_t *)DN_BONUS(mdn))->dd_child_dir_zapobj; 870 if (errnum = dnode_get(mosmdn, childobj, 871 DMU_OT_DSL_DIR_CHILD_MAP, mdn, stack)) 872 return (errnum); 873 874 if (zap_lookup(mdn, cname, &objnum, stack)) 875 return (ERR_FILESYSTEM_NOT_FOUND); 876 877 if (errnum = dnode_get(mosmdn, objnum, DMU_OT_DSL_DIR, 878 mdn, stack)) 879 return (errnum); 880 881 *fsname = ch; 882 } 883 headobj = ((dsl_dir_phys_t *)DN_BONUS(mdn))->dd_head_dataset_obj; 884 if (obj) 885 *obj = headobj; 886 887 skip: 888 if (errnum = dnode_get(mosmdn, headobj, DMU_OT_DSL_DATASET, mdn, stack)) 889 return (errnum); 890 891 /* TODO: Add snapshot support here - for fsname=snapshot-name */ 892 893 bp = &((dsl_dataset_phys_t *)DN_BONUS(mdn))->ds_bp; 894 osp = (objset_phys_t *)stack; 895 stack += sizeof (objset_phys_t); 896 if (errnum = zio_read(bp, osp, stack)) 897 return (errnum); 898 899 grub_memmove((char *)mdn, (char *)&osp->os_meta_dnode, DNODE_SIZE); 900 901 return (0); 902 } 903 904 /* 905 * For a given XDR packed nvlist, verify the first 4 bytes and move on. 906 * 907 * An XDR packed nvlist is encoded as (comments from nvs_xdr_create) : 908 * 909 * encoding method/host endian (4 bytes) 910 * nvl_version (4 bytes) 911 * nvl_nvflag (4 bytes) 912 * encoded nvpairs: 913 * encoded size of the nvpair (4 bytes) 914 * decoded size of the nvpair (4 bytes) 915 * name string size (4 bytes) 916 * name string data (sizeof(NV_ALIGN4(string)) 917 * data type (4 bytes) 918 * # of elements in the nvpair (4 bytes) 919 * data 920 * 2 zero's for the last nvpair 921 * (end of the entire list) (8 bytes) 922 * 923 * Return: 924 * 0 - success 925 * 1 - failure 926 */ 927 static int 928 nvlist_unpack(char *nvlist, char **out) 929 { 930 /* Verify if the 1st and 2nd byte in the nvlist are valid. */ 931 if (nvlist[0] != NV_ENCODE_XDR || nvlist[1] != HOST_ENDIAN) 932 return (1); 933 934 nvlist += 4; 935 *out = nvlist; 936 return (0); 937 } 938 939 static char * 940 nvlist_array(char *nvlist, int index) 941 { 942 int i, encode_size; 943 944 for (i = 0; i < index; i++) { 945 /* skip the header, nvl_version, and nvl_nvflag */ 946 nvlist = nvlist + 4 * 2; 947 948 while (encode_size = BSWAP_32(*(uint32_t *)nvlist)) 949 nvlist += encode_size; /* goto the next nvpair */ 950 951 nvlist = nvlist + 4 * 2; /* skip the ending 2 zeros - 8 bytes */ 952 } 953 954 return (nvlist); 955 } 956 957 static int 958 nvlist_lookup_value(char *nvlist, char *name, void *val, int valtype, 959 int *nelmp) 960 { 961 int name_len, type, slen, encode_size; 962 char *nvpair, *nvp_name, *strval = val; 963 uint64_t *intval = val; 964 965 /* skip the header, nvl_version, and nvl_nvflag */ 966 nvlist = nvlist + 4 * 2; 967 968 /* 969 * Loop thru the nvpair list 970 * The XDR representation of an integer is in big-endian byte order. 971 */ 972 while (encode_size = BSWAP_32(*(uint32_t *)nvlist)) { 973 974 nvpair = nvlist + 4 * 2; /* skip the encode/decode size */ 975 976 name_len = BSWAP_32(*(uint32_t *)nvpair); 977 nvpair += 4; 978 979 nvp_name = nvpair; 980 nvpair = nvpair + ((name_len + 3) & ~3); /* align */ 981 982 type = BSWAP_32(*(uint32_t *)nvpair); 983 nvpair += 4; 984 985 if ((grub_strncmp(nvp_name, name, name_len) == 0) && 986 type == valtype) { 987 int nelm; 988 989 if ((nelm = BSWAP_32(*(uint32_t *)nvpair)) < 1) 990 return (1); 991 nvpair += 4; 992 993 switch (valtype) { 994 case DATA_TYPE_STRING: 995 slen = BSWAP_32(*(uint32_t *)nvpair); 996 nvpair += 4; 997 grub_memmove(strval, nvpair, slen); 998 strval[slen] = '\0'; 999 return (0); 1000 1001 case DATA_TYPE_UINT64: 1002 *intval = BSWAP_64(*(uint64_t *)nvpair); 1003 return (0); 1004 1005 case DATA_TYPE_NVLIST: 1006 *(void **)val = (void *)nvpair; 1007 return (0); 1008 1009 case DATA_TYPE_NVLIST_ARRAY: 1010 *(void **)val = (void *)nvpair; 1011 if (nelmp) 1012 *nelmp = nelm; 1013 return (0); 1014 } 1015 } 1016 1017 nvlist += encode_size; /* goto the next nvpair */ 1018 } 1019 1020 return (1); 1021 } 1022 1023 /* 1024 * Check if this vdev is online and is in a good state. 1025 */ 1026 static int 1027 vdev_validate(char *nv) 1028 { 1029 uint64_t ival; 1030 1031 if (nvlist_lookup_value(nv, ZPOOL_CONFIG_OFFLINE, &ival, 1032 DATA_TYPE_UINT64, NULL) == 0 || 1033 nvlist_lookup_value(nv, ZPOOL_CONFIG_FAULTED, &ival, 1034 DATA_TYPE_UINT64, NULL) == 0 || 1035 nvlist_lookup_value(nv, ZPOOL_CONFIG_DEGRADED, &ival, 1036 DATA_TYPE_UINT64, NULL) == 0 || 1037 nvlist_lookup_value(nv, ZPOOL_CONFIG_REMOVED, &ival, 1038 DATA_TYPE_UINT64, NULL) == 0) 1039 return (ERR_DEV_VALUES); 1040 1041 return (0); 1042 } 1043 1044 /* 1045 * Get a list of valid vdev pathname from the boot device. 1046 * The caller should already allocate MAXNAMELEN memory for bootpath. 1047 */ 1048 static int 1049 vdev_get_bootpath(char *nv, char *bootpath) 1050 { 1051 char type[16]; 1052 1053 bootpath[0] = '\0'; 1054 if (nvlist_lookup_value(nv, ZPOOL_CONFIG_TYPE, &type, DATA_TYPE_STRING, 1055 NULL)) 1056 return (ERR_FSYS_CORRUPT); 1057 1058 if (strcmp(type, VDEV_TYPE_DISK) == 0) { 1059 if (vdev_validate(nv) != 0 || 1060 nvlist_lookup_value(nv, ZPOOL_CONFIG_PHYS_PATH, bootpath, 1061 DATA_TYPE_STRING, NULL) != 0) 1062 return (ERR_NO_BOOTPATH); 1063 1064 } else if (strcmp(type, VDEV_TYPE_MIRROR) == 0) { 1065 int nelm, i; 1066 char *child; 1067 1068 if (nvlist_lookup_value(nv, ZPOOL_CONFIG_CHILDREN, &child, 1069 DATA_TYPE_NVLIST_ARRAY, &nelm)) 1070 return (ERR_FSYS_CORRUPT); 1071 1072 for (i = 0; i < nelm; i++) { 1073 char tmp_path[MAXNAMELEN]; 1074 char *child_i; 1075 1076 child_i = nvlist_array(child, i); 1077 if (vdev_validate(child_i) != 0) 1078 continue; 1079 1080 if (nvlist_lookup_value(child_i, ZPOOL_CONFIG_PHYS_PATH, 1081 tmp_path, DATA_TYPE_STRING, NULL) != 0) 1082 return (ERR_NO_BOOTPATH); 1083 1084 if ((strlen(bootpath) + strlen(tmp_path)) > MAXNAMELEN) 1085 return (ERR_WONT_FIT); 1086 1087 if (strlen(bootpath) == 0) 1088 sprintf(bootpath, "%s", tmp_path); 1089 else 1090 sprintf(bootpath, "%s %s", bootpath, tmp_path); 1091 } 1092 } 1093 1094 return (strlen(bootpath) > 0 ? 0 : ERR_NO_BOOTPATH); 1095 } 1096 1097 /* 1098 * Check the disk label information and retrieve needed vdev name-value pairs. 1099 * 1100 * Return: 1101 * 0 - success 1102 * ERR_* - failure 1103 */ 1104 static int 1105 check_pool_label(int label, char *stack) 1106 { 1107 vdev_phys_t *vdev; 1108