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 /* 21 * Copyright 2010 Sun Microsystems, Inc. All rights reserved. 22 * Use is subject to license terms. 23 */ 24 25 /* 26 * Copyright (c) 2012, 2015 by Delphix. All rights reserved. 27 * Copyright (c) 2013 by Saso Kiselkov. All rights reserved. 28 * Copyright (c) 2014 Integros [integros.com] 29 */ 30 31 /* 32 * The zfs plug-in routines for GRUB are: 33 * 34 * zfs_mount() - locates a valid uberblock of the root pool and reads 35 * in its MOS at the memory address MOS. 36 * 37 * zfs_open() - locates a plain file object by following the MOS 38 * and places its dnode at the memory address DNODE. 39 * 40 * zfs_read() - read in the data blocks pointed by the DNODE. 41 * 42 * ZFS_SCRATCH is used as a working area. 43 * 44 * (memory addr) MOS DNODE ZFS_SCRATCH 45 * | | | 46 * +-------V---------V----------V---------------+ 47 * memory | | dnode | dnode | scratch | 48 * | | 512B | 512B | area | 49 * +--------------------------------------------+ 50 */ 51 52 #ifdef FSYS_ZFS 53 54 #include "shared.h" 55 #include "filesys.h" 56 #include "fsys_zfs.h" 57 58 /* cache for a file block of the currently zfs_open()-ed file */ 59 static void *file_buf = NULL; 60 static uint64_t file_start = 0; 61 static uint64_t file_end = 0; 62 63 /* cache for a dnode block */ 64 static dnode_phys_t *dnode_buf = NULL; 65 static dnode_phys_t *dnode_mdn = NULL; 66 static uint64_t dnode_start = 0; 67 static uint64_t dnode_end = 0; 68 69 static uint64_t pool_guid = 0; 70 static uberblock_t current_uberblock; 71 static char *stackbase; 72 73 decomp_entry_t decomp_table[ZIO_COMPRESS_FUNCTIONS] = 74 { 75 {"inherit", 0}, /* ZIO_COMPRESS_INHERIT */ 76 {"on", lzjb_decompress}, /* ZIO_COMPRESS_ON */ 77 {"off", 0}, /* ZIO_COMPRESS_OFF */ 78 {"lzjb", lzjb_decompress}, /* ZIO_COMPRESS_LZJB */ 79 {"empty", 0}, /* ZIO_COMPRESS_EMPTY */ 80 {"gzip-1", 0}, /* ZIO_COMPRESS_GZIP_1 */ 81 {"gzip-2", 0}, /* ZIO_COMPRESS_GZIP_2 */ 82 {"gzip-3", 0}, /* ZIO_COMPRESS_GZIP_3 */ 83 {"gzip-4", 0}, /* ZIO_COMPRESS_GZIP_4 */ 84 {"gzip-5", 0}, /* ZIO_COMPRESS_GZIP_5 */ 85 {"gzip-6", 0}, /* ZIO_COMPRESS_GZIP_6 */ 86 {"gzip-7", 0}, /* ZIO_COMPRESS_GZIP_7 */ 87 {"gzip-8", 0}, /* ZIO_COMPRESS_GZIP_8 */ 88 {"gzip-9", 0}, /* ZIO_COMPRESS_GZIP_9 */ 89 {"zle", 0}, /* ZIO_COMPRESS_ZLE */ 90 {"lz4", lz4_decompress} /* ZIO_COMPRESS_LZ4 */ 91 }; 92 93 static int zio_read_data(blkptr_t *bp, void *buf, char *stack); 94 95 /* 96 * Our own version of bcmp(). 97 */ 98 static int 99 zfs_bcmp(const void *s1, const void *s2, size_t n) 100 { 101 const uchar_t *ps1 = s1; 102 const uchar_t *ps2 = s2; 103 104 if (s1 != s2 && n != 0) { 105 do { 106 if (*ps1++ != *ps2++) 107 return (1); 108 } while (--n != 0); 109 } 110 111 return (0); 112 } 113 114 /* 115 * Our own version of log2(). Same thing as highbit()-1. 116 */ 117 static int 118 zfs_log2(uint64_t num) 119 { 120 int i = 0; 121 122 while (num > 1) { 123 i++; 124 num = num >> 1; 125 } 126 127 return (i); 128 } 129 130 /* Checksum Functions */ 131 static void 132 zio_checksum_off(const void *buf, uint64_t size, zio_cksum_t *zcp) 133 { 134 ZIO_SET_CHECKSUM(zcp, 0, 0, 0, 0); 135 } 136 137 /* Checksum Table and Values */ 138 zio_checksum_info_t zio_checksum_table[ZIO_CHECKSUM_FUNCTIONS] = { 139 {{NULL, NULL}, 0, 0, "inherit"}, 140 {{NULL, NULL}, 0, 0, "on"}, 141 {{zio_checksum_off, zio_checksum_off}, 0, 0, "off"}, 142 {{zio_checksum_SHA256, zio_checksum_SHA256}, 1, 1, "label"}, 143 {{zio_checksum_SHA256, zio_checksum_SHA256}, 1, 1, "gang_header"}, 144 {{NULL, NULL}, 0, 0, "zilog"}, 145 {{fletcher_2_native, fletcher_2_byteswap}, 0, 0, "fletcher2"}, 146 {{fletcher_4_native, fletcher_4_byteswap}, 1, 0, "fletcher4"}, 147 {{zio_checksum_SHA256, zio_checksum_SHA256}, 1, 0, "SHA256"}, 148 {{NULL, NULL}, 0, 0, "zilog2"}, 149 {{zio_checksum_off, zio_checksum_off}, 0, 0, "noparity"}, 150 {{zio_checksum_SHA512, NULL}, 0, 0, "SHA512"} 151 }; 152 153 /* 154 * zio_checksum_verify: Provides support for checksum verification. 155 * 156 * Fletcher2, Fletcher4, SHA-256 and SHA-512/256 are supported. 157 * 158 * Return: 159 * -1 = Failure 160 * 0 = Success 161 */ 162 static int 163 zio_checksum_verify(blkptr_t *bp, char *data, int size) 164 { 165 zio_cksum_t zc = bp->blk_cksum; 166 uint32_t checksum = BP_GET_CHECKSUM(bp); 167 int byteswap = BP_SHOULD_BYTESWAP(bp); 168 zio_eck_t *zec = (zio_eck_t *)(data + size) - 1; 169 zio_checksum_info_t *ci = &zio_checksum_table[checksum]; 170 zio_cksum_t actual_cksum, expected_cksum; 171 172 if (byteswap) { 173 grub_printf("byteswap not supported\n"); 174 return (-1); 175 } 176 177 if (checksum >= ZIO_CHECKSUM_FUNCTIONS || ci->ci_func[0] == NULL) { 178 grub_printf("checksum algorithm %u not supported\n", checksum); 179 return (-1); 180 } 181 182 if (ci->ci_eck) { 183 expected_cksum = zec->zec_cksum; 184 zec->zec_cksum = zc; 185 ci->ci_func[0](data, size, &actual_cksum); 186 zec->zec_cksum = expected_cksum; 187 zc = expected_cksum; 188 } else { 189 ci->ci_func[byteswap](data, size, &actual_cksum); 190 } 191 192 if ((actual_cksum.zc_word[0] - zc.zc_word[0]) | 193 (actual_cksum.zc_word[1] - zc.zc_word[1]) | 194 (actual_cksum.zc_word[2] - zc.zc_word[2]) | 195 (actual_cksum.zc_word[3] - zc.zc_word[3])) 196 return (-1); 197 198 return (0); 199 } 200 201 /* 202 * vdev_label_start returns the physical disk offset (in bytes) of 203 * label "l". 204 */ 205 static uint64_t 206 vdev_label_start(uint64_t psize, int l) 207 { 208 return (l * sizeof (vdev_label_t) + (l < VDEV_LABELS / 2 ? 209 0 : psize - VDEV_LABELS * sizeof (vdev_label_t))); 210 } 211 212 /* 213 * vdev_uberblock_compare takes two uberblock structures and returns an integer 214 * indicating the more recent of the two. 215 * Return Value = 1 if ub2 is more recent 216 * Return Value = -1 if ub1 is more recent 217 * The most recent uberblock is determined using its transaction number and 218 * timestamp. The uberblock with the highest transaction number is 219 * considered "newer". If the transaction numbers of the two blocks match, the 220 * timestamps are compared to determine the "newer" of the two. 221 */ 222 static int 223 vdev_uberblock_compare(uberblock_t *ub1, uberblock_t *ub2) 224 { 225 if (ub1->ub_txg < ub2->ub_txg) 226 return (-1); 227 if (ub1->ub_txg > ub2->ub_txg) 228 return (1); 229 230 if (ub1->ub_timestamp < ub2->ub_timestamp) 231 return (-1); 232 if (ub1->ub_timestamp > ub2->ub_timestamp) 233 return (1); 234 235 return (0); 236 } 237 238 /* 239 * Three pieces of information are needed to verify an uberblock: the magic 240 * number, the version number, and the checksum. 241 * 242 * Return: 243 * 0 - Success 244 * -1 - Failure 245 */ 246 static int 247 uberblock_verify(uberblock_t *uber, uint64_t ub_size, uint64_t offset) 248 { 249 blkptr_t bp; 250 251 BP_ZERO(&bp); 252 BP_SET_CHECKSUM(&bp, ZIO_CHECKSUM_LABEL); 253 BP_SET_BYTEORDER(&bp, ZFS_HOST_BYTEORDER); 254 ZIO_SET_CHECKSUM(&bp.blk_cksum, offset, 0, 0, 0); 255 256 if (zio_checksum_verify(&bp, (char *)uber, ub_size) != 0) 257 return (-1); 258 259 if (uber->ub_magic == UBERBLOCK_MAGIC && 260 SPA_VERSION_IS_SUPPORTED(uber->ub_version)) 261 return (0); 262 263 return (-1); 264 } 265 266 /* 267 * Find the best uberblock. 268 * Return: 269 * Success - Pointer to the best uberblock. 270 * Failure - NULL 271 */ 272 static uberblock_t * 273 find_bestub(char *ub_array, uint64_t ashift, uint64_t sector) 274 { 275 uberblock_t *ubbest = NULL; 276 uberblock_t *ubnext; 277 uint64_t offset, ub_size; 278 int i; 279 280 ub_size = VDEV_UBERBLOCK_SIZE(ashift); 281 282 for (i = 0; i < VDEV_UBERBLOCK_COUNT(ashift); i++) { 283 ubnext = (uberblock_t *)ub_array; 284 ub_array += ub_size; 285 offset = (sector << SPA_MINBLOCKSHIFT) + 286 VDEV_UBERBLOCK_OFFSET(ashift, i); 287 288 if (uberblock_verify(ubnext, ub_size, offset) != 0) 289 continue; 290 291 if (ubbest == NULL || 292 vdev_uberblock_compare(ubnext, ubbest) > 0) 293 ubbest = ubnext; 294 } 295 296 return (ubbest); 297 } 298 299 /* 300 * Read a block of data based on the gang block address dva, 301 * and put its data in buf. 302 * 303 * Return: 304 * 0 - success 305 * 1 - failure 306 */ 307 static int 308 zio_read_gang(blkptr_t *bp, dva_t *dva, void *buf, char *stack) 309 { 310 zio_gbh_phys_t *zio_gb; 311 uint64_t offset, sector; 312 blkptr_t tmpbp; 313 int i; 314 315 zio_gb = (zio_gbh_phys_t *)stack; 316 stack += SPA_GANGBLOCKSIZE; 317 offset = DVA_GET_OFFSET(dva); 318 sector = DVA_OFFSET_TO_PHYS_SECTOR(offset); 319 320 /* read in the gang block header */ 321 if (devread(sector, 0, SPA_GANGBLOCKSIZE, (char *)zio_gb) == 0) { 322 grub_printf("failed to read in a gang block header\n"); 323 return (1); 324 } 325 326 /* self checksuming the gang block header */ 327 BP_ZERO(&tmpbp); 328 BP_SET_CHECKSUM(&tmpbp, ZIO_CHECKSUM_GANG_HEADER); 329 BP_SET_BYTEORDER(&tmpbp, ZFS_HOST_BYTEORDER); 330 ZIO_SET_CHECKSUM(&tmpbp.blk_cksum, DVA_GET_VDEV(dva), 331 DVA_GET_OFFSET(dva), bp->blk_birth, 0); 332 if (zio_checksum_verify(&tmpbp, (char *)zio_gb, SPA_GANGBLOCKSIZE)) { 333 grub_printf("failed to checksum a gang block header\n"); 334 return (1); 335 } 336 337 for (i = 0; i < SPA_GBH_NBLKPTRS; i++) { 338 if (BP_IS_HOLE(&zio_gb->zg_blkptr[i])) 339 continue; 340 341 if (zio_read_data(&zio_gb->zg_blkptr[i], buf, stack)) 342 return (1); 343 buf += BP_GET_PSIZE(&zio_gb->zg_blkptr[i]); 344 } 345 346 return (0); 347 } 348 349 /* 350 * Read in a block of raw data to buf. 351 * 352 * Return: 353 * 0 - success 354 * 1 - failure 355 */ 356 static int 357 zio_read_data(blkptr_t *bp, void *buf, char *stack) 358 { 359 int i, psize; 360 361 psize = BP_GET_PSIZE(bp); 362 363 /* pick a good dva from the block pointer */ 364 for (i = 0; i < SPA_DVAS_PER_BP; i++) { 365 uint64_t offset, sector; 366 367 if (bp->blk_dva[i].dva_word[0] == 0 && 368 bp->blk_dva[i].dva_word[1] == 0) 369 continue; 370 371 if (DVA_GET_GANG(&bp->blk_dva[i])) { 372 if (zio_read_gang(bp, &bp->blk_dva[i], buf, stack) != 0) 373 continue; 374 } else { 375 /* read in a data block */ 376 offset = DVA_GET_OFFSET(&bp->blk_dva[i]); 377 sector = DVA_OFFSET_TO_PHYS_SECTOR(offset); 378 if (devread(sector, 0, psize, buf) == 0) 379 continue; 380 } 381 382 /* verify that the checksum matches */ 383 if (zio_checksum_verify(bp, buf, psize) == 0) { 384 return (0); 385 } 386 } 387 388 grub_printf("could not read block due to EIO or ECKSUM\n"); 389 return (1); 390 } 391 392 /* 393 * buf must be at least BPE_GET_PSIZE(bp) bytes long (which will never be 394 * more than BPE_PAYLOAD_SIZE bytes). 395 */ 396 static void 397 decode_embedded_bp_compressed(const blkptr_t *bp, void *buf) 398 { 399 int psize, i; 400 uint8_t *buf8 = buf; 401 uint64_t w = 0; 402 const uint64_t *bp64 = (const uint64_t *)bp; 403 404 psize = BPE_GET_PSIZE(bp); 405 406 /* 407 * Decode the words of the block pointer into the byte array. 408 * Low bits of first word are the first byte (little endian). 409 */ 410 for (i = 0; i < psize; i++) { 411 if (i % sizeof (w) == 0) { 412 /* beginning of a word */ 413 w = *bp64; 414 bp64++; 415 if (!BPE_IS_PAYLOADWORD(bp, bp64)) 416 bp64++; 417 } 418 buf8[i] = BF64_GET(w, (i % sizeof (w)) * NBBY, NBBY); 419 } 420 } 421 422 /* 423 * Fill in the buffer with the (decompressed) payload of the embedded 424 * blkptr_t. Takes into account compression and byteorder (the payload is 425 * treated as a stream of bytes). 426 * Return 0 on success, or ENOSPC if it won't fit in the buffer. 427 */ 428 static int 429 decode_embedded_bp(const blkptr_t *bp, void *buf) 430 { 431 int comp; 432 int lsize, psize; 433 uint8_t *dst = buf; 434 uint64_t w = 0; 435 436 lsize = BPE_GET_LSIZE(bp); 437 psize = BPE_GET_PSIZE(bp); 438 comp = BP_GET_COMPRESS(bp); 439 440 if (comp != ZIO_COMPRESS_OFF) { 441 uint8_t dstbuf[BPE_PAYLOAD_SIZE]; 442 443 if ((unsigned int)comp >= ZIO_COMPRESS_FUNCTIONS || 444 decomp_table[comp].decomp_func == NULL) { 445 grub_printf("compression algorithm not supported\n"); 446 return (ERR_FSYS_CORRUPT); 447 } 448 449 decode_embedded_bp_compressed(bp, dstbuf); 450 decomp_table[comp].decomp_func(dstbuf, buf, psize, lsize); 451 } else { 452 decode_embedded_bp_compressed(bp, buf); 453 } 454 455 return (0); 456 } 457 458 /* 459 * Read in a block of data, verify its checksum, decompress if needed, 460 * and put the uncompressed data in buf. 461 * 462 * Return: 463 * 0 - success 464 * errnum - failure 465 */ 466 static int 467 zio_read(blkptr_t *bp, void *buf, char *stack) 468 { 469 int lsize, psize, comp; 470 char *retbuf; 471 472 if (BP_IS_EMBEDDED(bp)) { 473 if (BPE_GET_ETYPE(bp) != BP_EMBEDDED_TYPE_DATA) { 474 grub_printf("unsupported embedded BP (type=%u)\n", 475 (int)BPE_GET_ETYPE(bp)); 476 return (ERR_FSYS_CORRUPT); 477 } 478 return (decode_embedded_bp(bp, buf)); 479 } 480 481 comp = BP_GET_COMPRESS(bp); 482 lsize = BP_GET_LSIZE(bp); 483 psize = BP_GET_PSIZE(bp); 484 485 if ((unsigned int)comp >= ZIO_COMPRESS_FUNCTIONS || 486 (comp != ZIO_COMPRESS_OFF && 487 decomp_table[comp].decomp_func == NULL)) { 488 grub_printf("compression algorithm not supported\n"); 489 return (ERR_FSYS_CORRUPT); 490 } 491 492 if ((char *)buf < stack && ((char *)buf) + lsize > stack) { 493 grub_printf("not enough memory to fit %u bytes on stack\n", 494 lsize); 495 return (ERR_WONT_FIT); 496 } 497 498 retbuf = buf; 499 if (comp != ZIO_COMPRESS_OFF) { 500 buf = stack; 501 stack += psize; 502 } 503 504 if (zio_read_data(bp, buf, stack) != 0) { 505 grub_printf("zio_read_data failed\n"); 506 return (ERR_FSYS_CORRUPT); 507 } 508 509 if (comp != ZIO_COMPRESS_OFF) { 510 if (decomp_table[comp].decomp_func(buf, retbuf, psize, 511 lsize) != 0) { 512 grub_printf("zio_read decompression failed\n"); 513 return (ERR_FSYS_CORRUPT); 514 } 515 } 516 517 return (0); 518 } 519 520 /* 521 * Get the block from a block id. 522 * push the block onto the stack. 523 * 524 * Return: 525 * 0 - success 526 * errnum - failure 527 */ 528 static int 529 dmu_read(dnode_phys_t *dn, uint64_t blkid, void *buf, char *stack) 530 { 531 int idx, level; 532 blkptr_t *bp_array = dn->dn_blkptr; 533 int epbs = dn->dn_indblkshift - SPA_BLKPTRSHIFT; 534 blkptr_t *bp, *tmpbuf; 535 536 bp = (blkptr_t *)stack; 537 stack += sizeof (blkptr_t); 538 539 tmpbuf = (blkptr_t *)stack; 540 stack += 1<<dn->dn_indblkshift; 541 542 for (level = dn->dn_nlevels - 1; level >= 0; level--) { 543 idx = (blkid >> (epbs * level)) & ((1<<epbs)-1); 544 *bp = bp_array[idx]; 545 if (level == 0) 546 tmpbuf = buf; 547 if (BP_IS_HOLE(bp)) { 548 grub_memset(buf, 0, 549 dn->dn_datablkszsec << SPA_MINBLOCKSHIFT); 550 break; 551 } else if (errnum = zio_read(bp, tmpbuf, stack)) { 552 return (errnum); 553 } 554 555 bp_array = tmpbuf; 556 } 557 558 return (0); 559 } 560 561 /* 562 * mzap_lookup: Looks up property described by "name" and returns the value 563 * in "value". 564 * 565 * Return: 566 * 0 - success 567 * errnum - failure 568 */ 569 static int 570 mzap_lookup(mzap_phys_t *zapobj, int objsize, const char *name, 571 uint64_t *value) 572 { 573 int i, chunks; 574 mzap_ent_phys_t *mzap_ent = zapobj->mz_chunk; 575 576 chunks = objsize / MZAP_ENT_LEN - 1; 577 for (i = 0; i < chunks; i++) { 578 if (grub_strcmp(mzap_ent[i].mze_name, name) == 0) { 579 *value = mzap_ent[i].mze_value; 580 return (0); 581 } 582 } 583 584 return (ERR_FSYS_CORRUPT); 585 } 586 587 static uint64_t 588 zap_hash(uint64_t salt, const char *name) 589 { 590 static uint64_t table[256]; 591 const uint8_t *cp; 592 uint8_t c; 593 uint64_t crc = salt; 594 595 if (table[128] == 0) { 596 uint64_t *ct; 597 int i, j; 598 for (i = 0; i < 256; i++) { 599 for (ct = table + i, *ct = i, j = 8; j > 0; j--) 600 *ct = (*ct >> 1) ^ (-(*ct & 1) & 601 ZFS_CRC64_POLY); 602 } 603 } 604 605 if (crc == 0 || table[128] != ZFS_CRC64_POLY) { 606 errnum = ERR_FSYS_CORRUPT; 607 return (0); 608 } 609 610 for (cp = (const uint8_t *)name; (c = *cp) != '\0'; cp++) 611 crc = (crc >> 8) ^ table[(crc ^ c) & 0xFF]; 612 613 /* 614 * Only use 28 bits, since we need 4 bits in the cookie for the 615 * collision differentiator. We MUST use the high bits, since 616 * those are the ones that we first pay attention to when 617 * choosing the bucket. 618 */ 619 crc &= ~((1ULL << (64 - 28)) - 1); 620 621 return (crc); 622 } 623 624 /* 625 * Only to be used on 8-bit arrays. 626 * array_len is actual len in bytes (not encoded le_value_length). 627 * buf is null-terminated. 628 */ 629 static int 630 zap_leaf_array_equal(zap_leaf_phys_t *l, int blksft, int chunk, 631 int array_len, const char *buf) 632 { 633 int bseen = 0; 634 635 while (bseen < array_len) { 636 struct zap_leaf_array *la = 637 &ZAP_LEAF_CHUNK(l, blksft, chunk).l_array; 638 int toread = MIN(array_len - bseen, ZAP_LEAF_ARRAY_BYTES); 639 640 if (chunk >= ZAP_LEAF_NUMCHUNKS(blksft)) 641 return (0); 642 643 if (zfs_bcmp(la->la_array, buf + bseen, toread) != 0) 644 break; 645 chunk = la->la_next; 646 bseen += toread; 647 } 648 return (bseen == array_len); 649 } 650 651 /* 652 * Given a zap_leaf_phys_t, walk thru the zap leaf chunks to get the 653 * value for the property "name". 654 * 655 * Return: 656 * 0 - success 657 * errnum - failure 658 */ 659 static int 660 zap_leaf_lookup(zap_leaf_phys_t *l, int blksft, uint64_t h, 661 const char *name, uint64_t *value) 662 { 663 uint16_t chunk; 664 struct zap_leaf_entry *le; 665 666 /* Verify if this is a valid leaf block */ 667 if (l->l_hdr.lh_block_type != ZBT_LEAF) 668 return (ERR_FSYS_CORRUPT); 669 if (l->l_hdr.lh_magic != ZAP_LEAF_MAGIC) 670 return (ERR_FSYS_CORRUPT); 671 672 for (chunk = l->l_hash[LEAF_HASH(blksft, h)]; 673 chunk != CHAIN_END; chunk = le->le_next) { 674 675 if (chunk >= ZAP_LEAF_NUMCHUNKS(blksft)) 676 return (ERR_FSYS_CORRUPT); 677 678 le = ZAP_LEAF_ENTRY(l, blksft, chunk); 679 680 /* Verify the chunk entry */ 681 if (le->le_type != ZAP_CHUNK_ENTRY) 682 return (ERR_FSYS_CORRUPT); 683 684 if (le->le_hash != h) 685 continue; 686 687 if (zap_leaf_array_equal(l, blksft, le->le_name_chunk, 688 le->le_name_length, name)) { 689 690 struct zap_leaf_array *la; 691 uint8_t *ip; 692 693 if (le->le_int_size != 8 || le->le_value_length != 1) 694 return (ERR_FSYS_CORRUPT); 695 696 /* get the uint64_t property value */ 697 la = &ZAP_LEAF_CHUNK(l, blksft, 698 le->le_value_chunk).l_array; 699 ip = la->la_array; 700 701 *value = (uint64_t)ip[0] << 56 | (uint64_t)ip[1] << 48 | 702 (uint64_t)ip[2] << 40 | (uint64_t)ip[3] << 32 | 703 (uint64_t)ip[4] << 24 | (uint64_t)ip[5] << 16 | 704 (uint64_t)ip[6] << 8 | (uint64_t)ip[7]; 705 706 return (0); 707 } 708 } 709 710 return (ERR_FSYS_CORRUPT); 711 } 712 713 /* 714 * Fat ZAP lookup 715 * 716 * Return: 717 * 0 - success 718 * errnum - failure 719 */ 720 static int 721 fzap_lookup(dnode_phys_t *zap_dnode, zap_phys_t *zap, 722 const char *name, uint64_t *value, char *stack) 723 { 724 zap_leaf_phys_t *l; 725 uint64_t hash, idx, blkid; 726 int blksft = zfs_log2(zap_dnode->dn_datablkszsec << DNODE_SHIFT); 727 728 /* Verify if this is a fat zap header block */ 729 if (zap->zap_magic != (uint64_t)ZAP_MAGIC || 730 zap->zap_flags != 0) 731 return (ERR_FSYS_CORRUPT); 732 733 hash = zap_hash(zap->zap_salt, name); 734 if (errnum) 735 return (errnum); 736 737 /* get block id from index */ 738 if (zap->zap_ptrtbl.zt_numblks != 0) { 739 /* external pointer tables not supported */ 740 return (ERR_FSYS_CORRUPT); 741 } 742 idx = ZAP_HASH_IDX(hash, zap->zap_ptrtbl.zt_shift); 743 blkid = ((uint64_t *)zap)[idx + (1<<(blksft-3-1))]; 744 745 /* Get the leaf block */ 746 l = (zap_leaf_phys_t *)stack; 747 stack += 1<<blksft; 748 if ((1<<blksft) < sizeof (zap_leaf_phys_t)) 749 return (ERR_FSYS_CORRUPT); 750 if (errnum = dmu_read(zap_dnode, blkid, l, stack)) 751 return (errnum); 752 753 return (zap_leaf_lookup(l, blksft, hash, name, value)); 754 } 755 756 /* 757 * Read in the data of a zap object and find the value for a matching 758 * property name. 759 * 760 * Return: 761 * 0 - success 762 * errnum - failure 763 */ 764 static int 765 zap_lookup(dnode_phys_t *zap_dnode, const char *name, uint64_t *val, 766 char *stack) 767 { 768 uint64_t block_type; 769 int size; 770 void *zapbuf; 771 772 /* Read in the first block of the zap object data. */ 773 zapbuf = stack; 774 size = zap_dnode->dn_datablkszsec << SPA_MINBLOCKSHIFT; 775 stack += size; 776 777 if ((errnum = dmu_read(zap_dnode, 0, zapbuf, stack)) != 0) 778 return (errnum); 779 780 block_type = *((uint64_t *)zapbuf); 781 782 if (block_type == ZBT_MICRO) { 783 return (mzap_lookup(zapbuf, size, name, val)); 784 } else if (block_type == ZBT_HEADER) { 785 /* this is a fat zap */ 786 return (fzap_lookup(zap_dnode, zapbuf, name, 787 val, stack)); 788 } 789 790 return (ERR_FSYS_CORRUPT); 791 } 792 793 typedef struct zap_attribute { 794 int za_integer_length; 795 uint64_t za_num_integers; 796 uint64_t za_first_integer; 797 char *za_name; 798 } zap_attribute_t; 799 800 typedef int (zap_cb_t)(zap_attribute_t *za, void *arg, char *stack); 801 802 static int 803 zap_iterate(dnode_phys_t *zap_dnode, zap_cb_t *cb, void *arg, char *stack) 804 { 805 uint32_t size = zap_dnode->dn_datablkszsec << SPA_MINBLOCKSHIFT; 806 zap_attribute_t za; 807 int i; 808 mzap_phys_t *mzp = (mzap_phys_t *)stack; 809 stack += size; 810 811 if ((errnum = dmu_read(zap_dnode, 0, mzp, stack)) != 0) 812 return (errnum); 813 814 /* 815 * Iteration over fatzap objects has not yet been implemented. 816 * If we encounter a pool in which there are more features for 817 * read than can fit inside a microzap (i.e., more than 2048 818 * features for read), we can add support for fatzap iteration. 819 * For now, fail. 820 */ 821 if (mzp->mz_block_type != ZBT_MICRO) { 822 grub_printf("feature information stored in fatzap, pool " 823 "version not supported\n"); 824 return (1); 825 } 826 827 za.za_integer_length = 8; 828 za.za_num_integers = 1; 829 for (i = 0; i < size / MZAP_ENT_LEN - 1; i++) { 830 mzap_ent_phys_t *mzep = &mzp->mz_chunk[i]; 831 int err; 832 833 za.za_first_integer = mzep->mze_value; 834 za.za_name = mzep->mze_name; 835 err = cb(&za, arg, stack); 836 if (err != 0) 837 return (err); 838 } 839 840 return (0); 841 } 842 843 /* 844 * Get the dnode of an object number from the metadnode of an object set. 845 * 846 * Input 847 * mdn - metadnode to get the object dnode 848 * objnum - object number for the object dnode 849 * type - if nonzero, object must be of this type 850 * buf - data buffer that holds the returning dnode 851 * stack - scratch area 852 * 853 * Return: 854 * 0 - success 855 * errnum - failure 856 */ 857 static int 858 dnode_get(dnode_phys_t *mdn, uint64_t objnum, uint8_t type, dnode_phys_t *buf, 859 char *stack) 860 { 861 uint64_t blkid, blksz; /* the block id this object dnode is in */ 862 int epbs; /* shift of number of dnodes in a block */ 863 int idx; /* index within a block */ 864 dnode_phys_t *dnbuf; 865 866 blksz = mdn->dn_datablkszsec << SPA_MINBLOCKSHIFT; 867 epbs = zfs_log2(blksz) - DNODE_SHIFT; 868 blkid = objnum >> epbs; 869 idx = objnum & ((1<<epbs)-1); 870 871 if (dnode_buf != NULL && dnode_mdn == mdn && 872 objnum >= dnode_start && objnum < dnode_end) { 873 grub_memmove(buf, &dnode_buf[idx], DNODE_SIZE); 874 VERIFY_DN_TYPE(buf, type); 875 return (0); 876 } 877 878 if (dnode_buf && blksz == 1<<DNODE_BLOCK_SHIFT) { 879 dnbuf = dnode_buf; 880 dnode_mdn = mdn; 881 dnode_start = blkid << epbs; 882 dnode_end = (blkid + 1) << epbs; 883 } else { 884 dnbuf = (dnode_phys_t *)stack; 885 stack += blksz; 886 } 887 888 if (errnum = dmu_read(mdn, blkid, (char *)dnbuf, stack)) 889 return (errnum); 890 891 grub_memmove(buf, &dnbuf[idx], DNODE_SIZE); 892 VERIFY_DN_TYPE(buf, type); 893 894 return (0); 895 } 896 897 /* 898 * Check if this is a special file that resides at the top 899 * dataset of the pool. Currently this is the GRUB menu, 900 * boot signature and boot signature backup. 901 * str starts with '/'. 902 */ 903 static int 904 is_top_dataset_file(char *str) 905 { 906 char *tptr; 907 908 if ((tptr = grub_strstr(str, "menu.lst")) && 909 (tptr[8] == '\0' || tptr[8] == ' ') && 910 *(tptr-1) == '/') 911 return (1); 912 913 if (grub_strncmp(str, BOOTSIGN_DIR"/", 914 grub_strlen(BOOTSIGN_DIR) + 1) == 0) 915 return (1); 916 917 if (grub_strcmp(str, BOOTSIGN_BACKUP) == 0) 918 return (1); 919 920 return (0); 921 } 922 923 static int 924 check_feature(zap_attribute_t *za, void *arg, char *stack) 925 { 926 const char **names = arg; 927 int i; 928 929 if (za->za_first_integer == 0) 930 return (0); 931 932 for (i = 0; names[i] != NULL; i++) { 933 if (grub_strcmp(za->za_name, names[i]) == 0) { 934 return (0); 935 } 936 } 937 grub_printf("missing feature for read '%s'\n", za->za_name); 938 return (ERR_NEWER_VERSION); 939 } 940 941 /* 942 * Get the file dnode for a given file name where mdn is the meta dnode 943 * for this ZFS object set. When found, place the file dnode in dn. 944 * The 'path' argument will be mangled. 945 * 946 * Return: 947 * 0 - success 948 * errnum - failure 949 */ 950 static int 951 dnode_get_path(dnode_phys_t *mdn, char *path, dnode_phys_t *dn, 952 char *stack) 953 { 954 uint64_t objnum, version; 955 char *cname, ch; 956 957 if (errnum = dnode_get(mdn, MASTER_NODE_OBJ, DMU_OT_MASTER_NODE, 958 dn, stack)) 959 return (errnum); 960 961 if (errnum = zap_lookup(dn, ZPL_VERSION_STR, &version, stack)) 962 return (errnum); 963 if (version > ZPL_VERSION) 964 return (-1); 965 966 if (errnum = zap_lookup(dn, ZFS_ROOT_OBJ, &objnum, stack)) 967 return (errnum); 968 969 if (errnum = dnode_get(mdn, objnum, DMU_OT_DIRECTORY_CONTENTS, 970 dn, stack)) 971 return (errnum); 972 973 /* skip leading slashes */ 974 while (*path == '/') 975 path++; 976 977 while (*path && !grub_isspace(*path)) { 978 979 /* get the next component name */ 980 cname = path; 981 while (*path && !grub_isspace(*path) && *path != '/') 982 path++; 983 ch = *path; 984 *path = 0; /* ensure null termination */ 985 986 if (errnum = zap_lookup(dn, cname, &objnum, stack)) 987 return (errnum); 988 989 objnum = ZFS_DIRENT_OBJ(objnum); 990 if (errnum = dnode_get(mdn, objnum, 0, dn, stack)) 991 return (errnum); 992 993 *path = ch; 994 while (*path == '/') 995 path++; 996 } 997 998 /* We found the dnode for this file. Verify if it is a plain file. */ 999 VERIFY_DN_TYPE(dn, DMU_OT_PLAIN_FILE_CONTENTS); 1000 1001 return (0); 1002 } 1003 1004 /* 1005 * Get the default 'bootfs' property value from the rootpool. 1006 * 1007 * Return: 1008 * 0 - success 1009 * errnum -failure 1010 */ 1011 static int 1012 get_default_bootfsobj(dnode_phys_t *mosmdn, uint64_t *obj, char *stack) 1013 { 1014 uint64_t objnum = 0; 1015 dnode_phys_t *dn = (dnode_phys_t *)stack; 1016 stack += DNODE_SIZE; 1017 1018 if (errnum = dnode_get(mosmdn, DMU_POOL_DIRECTORY_OBJECT, 1019 DMU_OT_OBJECT_DIRECTORY, dn, stack)) 1020 return (errnum); 1021 1022 /* 1023 * find the object number for 'pool_props', and get the dnode 1024 * of the 'pool_props'. 1025 */ 1026 if (zap_lookup(dn, DMU_POOL_PROPS, &objnum, stack)) 1027 return (ERR_FILESYSTEM_NOT_FOUND); 1028 1029 if (errnum = dnode_get(mosmdn, objnum, DMU_OT_POOL_PROPS, dn, stack)) 1030 return (errnum); 1031 1032 if (zap_lookup(dn, ZPOOL_PROP_BOOTFS, &objnum, stack)) 1033 return (ERR_FILESYSTEM_NOT_FOUND); 1034 1035 if (!objnum) 1036 return (ERR_FILESYSTEM_NOT_FOUND); 1037 1038 *obj = objnum; 1039 return (0); 1040 } 1041 1042 /* 1043 * List of pool features that the grub implementation of ZFS supports for 1044 * read. Note that features that are only required for write do not need 1045 * to be listed here since grub opens pools in read-only mode. 1046 * 1047 * When this list is updated the version number in usr/src/grub/capability 1048 * must be incremented to ensure the new grub gets installed. 1049 */ 1050 static const char *spa_feature_names[] = { 1051 "org.illumos:lz4_compress", 1052 "com.delphix:hole_birth", 1053 "com.delphix:extensible_dataset", 1054 "com.delphix:embedded_data", 1055 "org.open-zfs:large_blocks", 1056 "org.illumos:sha512", 1057 NULL 1058 }; 1059 1060 /* 1061 * Checks whether the MOS features that are active are supported by this 1062 * (GRUB's) implementation of ZFS. 1063 * 1064 * Return: 1065 * 0: Success. 1066 * errnum: Failure. 1067 */ 1068 static int 1069 check_mos_features(dnode_phys_t *mosmdn, char *stack) 1070 { 1071 uint64_t objnum; 1072 dnode_phys_t *dn; 1073 uint8_t error = 0; 1074 1075 dn = (dnode_phys_t *)stack; 1076 stack += DNODE_SIZE; 1077 1078 if ((errnum = dnode_get(mosmdn, DMU_POOL_DIRECTORY_OBJECT, 1079 DMU_OT_OBJECT_DIRECTORY, dn, stack)) != 0) 1080 return (errnum); 1081 1082 /* 1083 * Find the object number for 'features_for_read' and retrieve its 1084 * corresponding dnode. Note that we don't check features_for_write 1085 * because GRUB is not opening the pool for write. 1086 */ 1087 if ((errnum = zap_lookup(dn, DMU_POOL_FEATURES_FOR_READ, &objnum, 1088 stack)) != 0) 1089 return (errnum); 1090 1091 if ((errnum = dnode_get(mosmdn, objnum, DMU_OTN_ZAP_METADATA, 1092 dn, stack)) != 0) 1093 return (errnum); 1094 1095 return (zap_iterate(dn, check_feature, spa_feature_names, stack)); 1096 } 1097 1098 /* 1099 * Given a MOS metadnode, get the metadnode of a given filesystem name (fsname), 1100 * e.g. pool/rootfs, or a given object number (obj), e.g. the object number 1101 * of pool/rootfs. 1102 * 1103 * If no fsname and no obj are given, return the DSL_DIR metadnode. 1104 * If fsname is given, return its metadnode and its matching object number. 1105 * If only obj is given, return the metadnode for this object number. 1106 * 1107 * Return: 1108 * 0 - success 1109 * errnum - failure 1110 */ 1111 static int 1112 get_objset_mdn(dnode_phys_t *mosmdn, char *fsname, uint64_t *obj, 1113 dnode_phys_t *mdn, char *stack) 1114 { 1115 uint64_t objnum, headobj; 1116 char *cname, ch; 1117 blkptr_t *bp; 1118 objset_phys_t *osp; 1119 int issnapshot = 0; 1120 char *snapname; 1121 1122 if (fsname == NULL && obj) { 1123 headobj = *obj; 1124 goto skip; 1125 } 1126 1127 if (errnum = dnode_get(mosmdn, DMU_POOL_DIRECTORY_OBJECT, 1128 DMU_OT_OBJECT_DIRECTORY, mdn, stack)) 1129 return (errnum); 1130 1131 if (errnum = zap_lookup(mdn, DMU_POOL_ROOT_DATASET, &objnum, 1132 stack)) 1133 return (errnum); 1134 1135 if (errnum = dnode_get(mosmdn, objnum, 0, mdn, stack)) 1136 return (errnum); 1137 1138 if (fsname == NULL) { 1139 headobj = 1140 ((dsl_dir_phys_t *)DN_BONUS(mdn))->dd_head_dataset_obj; 1141 goto skip; 1142 } 1143 1144 /* take out the pool name */ 1145 while (*fsname && !grub_isspace(*fsname) && *fsname != '/') 1146 fsname++; 1147 1148 while (*fsname && !grub_isspace(*fsname)) { 1149 uint64_t childobj; 1150 1151 while (*fsname == '/') 1152 fsname++; 1153 1154 cname = fsname; 1155 while (*fsname && !grub_isspace(*fsname) && *fsname != '/') 1156 fsname++; 1157 ch = *fsname; 1158 *fsname = 0; 1159 1160 snapname = cname; 1161 while (*snapname && !grub_isspace(*snapname) && *snapname != 1162 '@') 1163 snapname++; 1164 if (*snapname == '@') { 1165 issnapshot = 1; 1166 *snapname = 0; 1167 } 1168 childobj = 1169 ((dsl_dir_phys_t *)DN_BONUS(mdn))->dd_child_dir_zapobj; 1170 if (errnum = dnode_get(mosmdn, childobj, 1171 DMU_OT_DSL_DIR_CHILD_MAP, mdn, stack)) 1172 return (errnum); 1173 1174 if (zap_lookup(mdn, cname, &objnum, stack)) 1175 return (ERR_FILESYSTEM_NOT_FOUND); 1176 1177 if (errnum = dnode_get(mosmdn, objnum, 0, 1178 mdn, stack)) 1179 return (errnum); 1180 1181 *fsname = ch; 1182 if (issnapshot) 1183 *snapname = '@'; 1184 } 1185 headobj = ((dsl_dir_phys_t *)DN_BONUS(mdn))->dd_head_dataset_obj; 1186 if (obj) 1187 *obj = headobj; 1188 1189 skip: 1190 if (errnum = dnode_get(mosmdn, headobj, 0, mdn, stack)) 1191 return (errnum); 1192 if (issnapshot) { 1193 uint64_t snapobj; 1194 1195 snapobj = ((dsl_dataset_phys_t *)DN_BONUS(mdn))-> 1196 ds_snapnames_zapobj; 1197 1198 if (errnum = dnode_get(mosmdn, snapobj, 1199 DMU_OT_DSL_DS_SNAP_MAP, mdn, stack)) 1200 return (errnum); 1201 if (zap_lookup(mdn, snapname + 1, &headobj, stack)) 1202 return (ERR_FILESYSTEM_NOT_FOUND); 1203 if (errnum = dnode_get(mosmdn, headobj, 0, mdn, stack)) 1204 return (errnum); 1205 if (obj) 1206 *obj = headobj; 1207 } 1208 1209 bp = &((dsl_dataset_phys_t *)DN_BONUS(mdn))->ds_bp; 1210 osp = (objset_phys_t *)stack; 1211 stack += sizeof (objset_phys_t); 1212 if (errnum = zio_read(bp, osp, stack)) 1213 return (errnum); 1214 1215 grub_memmove((char *)mdn, (char *)&osp->os_meta_dnode, DNODE_SIZE); 1216 1217 return (0); 1218 } 1219 1220 /* 1221 * For a given XDR packed nvlist, verify the first 4 bytes and move on. 1222 * 1223 * An XDR packed nvlist is encoded as (comments from nvs_xdr_create) : 1224 * 1225 * encoding method/host endian (4 bytes) 1226 * nvl_version (4 bytes) 1227 * nvl_nvflag (4 bytes) 1228 * encoded nvpairs: 1229 * encoded size of the nvpair (4 bytes) 1230 * decoded size of the nvpair (4 bytes) 1231 * name string size (4 bytes) 1232 * name string data (sizeof(NV_ALIGN4(string)) 1233 * data type (4 bytes) 1234 * # of elements in the nvpair (4 bytes) 1235 * data 1236 * 2 zero's for the last nvpair 1237 * (end of the entire list) (8 bytes) 1238 * 1239 * Return: 1240 * 0 - success 1241 * 1 - failure 1242 */ 1243 static int 1244 nvlist_unpack(char *nvlist, char **out) 1245 { 1246 /* Verify if the 1st and 2nd byte in the nvlist are valid. */ 1247 if (nvlist[0] != NV_ENCODE_XDR || nvlist[1] != HOST_ENDIAN) 1248 return (1); 1249 1250 *out = nvlist + 4; 1251 return (0); 1252 } 1253 1254 static char * 1255 nvlist_array(char *nvlist, int index) 1256 { 1257 int i, encode_size; 1258 1259 for (i = 0; i < index; i++) { 1260 /* skip the header, nvl_version, and nvl_nvflag */ 1261 nvlist = nvlist + 4 * 2; 1262 1263 while (encode_size = BSWAP_32(*(uint32_t *)nvlist)) 1264 nvlist += encode_size; /* goto the next nvpair */ 1265 1266 nvlist = nvlist + 4 * 2; /* skip the ending 2 zeros - 8 bytes */ 1267 } 1268 1269 return (nvlist); 1270 } 1271 1272 /* 1273 * The nvlist_next_nvpair() function returns a handle to the next nvpair in the 1274 * list following nvpair. If nvpair is NULL, the first pair is returned. If 1275 * nvpair is the last pair in the nvlist, NULL is returned. 1276 */ 1277 static char * 1278 nvlist_next_nvpair(char *nvl, char *nvpair) 1279 { 1280 char *cur, *prev; 1281 int encode_size; 1282 1283 if (nvl == NULL) 1284 return (NULL); 1285 1286 if (nvpair == NULL) { 1287 /* skip over nvl_version and nvl_nvflag */ 1288 nvpair = nvl + 4 * 2; 1289 } else { 1290 /* skip to the next nvpair */ 1291 encode_size = BSWAP_32(*(uint32_t *)nvpair); 1292 nvpair += encode_size; 1293 } 1294 1295 /* 8 bytes of 0 marks the end of the list */ 1296 if (*(uint64_t *)nvpair == 0) 1297 return (NULL); 1298 1299 return (nvpair); 1300 } 1301 1302 /* 1303 * This function returns 0 on success and 1 on failure. On success, a string 1304 * containing the name of nvpair is saved in buf. 1305 */ 1306 static int 1307 nvpair_name(char *nvp, char *buf, int buflen) 1308 { 1309 int len; 1310 1311 /* skip over encode/decode size */ 1312 nvp += 4 * 2; 1313 1314 len = BSWAP_32(*(uint32_t *)nvp); 1315 if (buflen < len + 1) 1316 return (1); 1317 1318 grub_memmove(buf, nvp + 4, len); 1319 buf[len] = '\0'; 1320 1321 return (0); 1322 } 1323 1324 /* 1325 * This function retrieves the value of the nvpair in the form of enumerated 1326 * type data_type_t. This is used to determine the appropriate type to pass to 1327 * nvpair_value(). 1328 */ 1329 static int 1330 nvpair_type(char *nvp) 1331 { 1332 int name_len, type; 1333 1334 /* skip over encode/decode size */ 1335 nvp += 4 * 2; 1336 1337 /* skip over name_len */ 1338 name_len = BSWAP_32(*(uint32_t *)nvp); 1339 nvp += 4; 1340 1341 /* skip over name */ 1342 nvp = nvp + ((name_len + 3) & ~3); /* align */ 1343 1344 type = BSWAP_32(*(uint32_t *)nvp); 1345 1346 return (type); 1347 } 1348 1349 static int 1350 nvpair_value(char *nvp, void *val, int valtype, int *nelmp) 1351 { 1352 int name_len, type, slen; 1353 char *strval = val; 1354 uint64_t *intval = val; 1355 1356 /* skip over encode/decode size */ 1357 nvp += 4 * 2; 1358 1359 /* skip over name_len */ 1360 name_len = BSWAP_32(*(uint32_t *)nvp); 1361 nvp += 4; 1362 1363 /* skip over name */ 1364 nvp = nvp + ((name_len + 3) & ~3); /* align */ 1365 1366 /* skip over type */ 1367 type = BSWAP_32(*(uint32_t *)nvp); 1368 nvp += 4; 1369 1370 if (type == valtype) { 1371 int nelm; 1372 1373 nelm = BSWAP_32(*(uint32_t *)nvp); 1374 if (valtype != DATA_TYPE_BOOLEAN && nelm < 1) 1375 return (1); 1376 nvp += 4; 1377 1378 switch (valtype) { 1379 case DATA_TYPE_BOOLEAN: 1380 return (0); 1381 1382 case DATA_TYPE_STRING: 1383 slen = BSWAP_32(*(uint32_t *)nvp); 1384 nvp += 4; 1385 grub_memmove(strval, nvp, slen); 1386 strval[slen] = '\0'; 1387 return (0); 1388 1389 case DATA_TYPE_UINT64: 1390 *intval = BSWAP_64(*(uint64_t *)nvp); 1391 return (0); 1392 1393 case DATA_TYPE_NVLIST: 1394 *(void **)val = (void *)nvp; 1395 return (0); 1396 1397 case DATA_TYPE_NVLIST_ARRAY: 1398 *(void **)val = (void *)nvp; 1399 if (nelmp) 1400 *nelmp = nelm; 1401 return (0); 1402 } 1403 } 1404 1405 return (1); 1406 } 1407 1408 static int 1409 nvlist_lookup_value(char *nvlist, char *name, void *val, int valtype, 1410 int *nelmp) 1411 { 1412 char *nvpair; 1413 1414 for (nvpair = nvlist_next_nvpair(nvlist, NULL); 1415 nvpair != NULL; 1416 nvpair = nvlist_next_nvpair(nvlist, nvpair)) { 1417 int name_len = BSWAP_32(*(uint32_t *)(nvpair + 4 * 2)); 1418 char *nvp_name = nvpair + 4 * 3; 1419 1420 if ((grub_strncmp(nvp_name, name, name_len) == 0) && 1421 nvpair_type(nvpair) == valtype) { 1422 return (nvpair_value(nvpair, val, valtype, nelmp)); 1423 } 1424 } 1425 return (1); 1426 } 1427 1428 /* 1429 * Check if this vdev is online and is in a good state. 1430 */ 1431 static int 1432 vdev_validate(char *nv) 1433 { 1434 uint64_t ival; 1435 1436 if (nvlist_lookup_value(nv, ZPOOL_CONFIG_OFFLINE, &ival, 1437 DATA_TYPE_UINT64, NULL) == 0 || 1438 nvlist_lookup_value(nv, ZPOOL_CONFIG_FAULTED, &ival, 1439 DATA_TYPE_UINT64, NULL) == 0 || 1440 nvlist_lookup_value(nv, ZPOOL_CONFIG_REMOVED, &ival, 1441 DATA_TYPE_UINT64, NULL) == 0) 1442 return (ERR_DEV_VALUES); 1443 1444 return (0); 1445 } 1446 1447 /* 1448 * Get a valid vdev pathname/devid from the boot device. 1449 * The caller should already allocate MAXPATHLEN memory for bootpath and devid. 1450 */ 1451 static int 1452 vdev_get_bootpath(char *nv, uint64_t inguid, char *devid, char *bootpath, 1453 int is_spare) 1454 { 1455 char type[16]; 1456 1457 if (nvlist_lookup_value(nv, ZPOOL_CONFIG_TYPE, &type, DATA_TYPE_STRING, 1458 NULL)) 1459 return (ERR_FSYS_CORRUPT); 1460 1461 if (grub_strcmp(type, VDEV_TYPE_DISK) == 0) { 1462 uint64_t guid; 1463 1464 if (vdev_validate(nv) != 0) 1465 return (ERR_NO_BOOTPATH); 1466 1467 if (nvlist_lookup_value(nv, ZPOOL_CONFIG_GUID, 1468 &guid, DATA_TYPE_UINT64, NULL) != 0) 1469 return (ERR_NO_BOOTPATH); 1470 1471 if (guid != inguid) 1472 return (ERR_NO_BOOTPATH); 1473 1474 /* for a spare vdev, pick the disk labeled with "is_spare" */ 1475 if (is_spare) { 1476 uint64_t spare = 0; 1477 (void) nvlist_lookup_value(nv, ZPOOL_CONFIG_IS_SPARE, 1478 &spare, DATA_TYPE_UINT64, NULL); 1479 if (!spare) 1480 return (ERR_NO_BOOTPATH); 1481 } 1482 1483 if (nvlist_lookup_value(nv, ZPOOL_CONFIG_PHYS_PATH, 1484 bootpath, DATA_TYPE_STRING, NULL) != 0) 1485 bootpath[0] = '\0'; 1486 1487 if (nvlist_lookup_value(nv, ZPOOL_CONFIG_DEVID, 1488 devid, DATA_TYPE_STRING, NULL) != 0) 1489 devid[0] = '\0'; 1490 1491 if (grub_strlen(bootpath) >= MAXPATHLEN || 1492 grub_strlen(devid) >= MAXPATHLEN) 1493 return (ERR_WONT_FIT); 1494 1495 return (0); 1496 1497 } else if (grub_strcmp(type, VDEV_TYPE_MIRROR) == 0 || 1498 grub_strcmp(type, VDEV_TYPE_REPLACING) == 0 || 1499 (is_spare = (grub_strcmp(type, VDEV_TYPE_SPARE) == 0))) { 1500 int nelm, i; 1501 char *child; 1502 1503 if (nvlist_lookup_value(nv, ZPOOL_CONFIG_CHILDREN, &child, 1504 DATA_TYPE_NVLIST_ARRAY, &nelm)) 1505 return (ERR_FSYS_CORRUPT); 1506 1507 for (i = 0; i < nelm; i++) { 1508 char *child_i; 1509 1510 child_i = nvlist_array(child, i); 1511 if (vdev_get_bootpath(child_i, inguid, devid, 1512 bootpath, is_spare) == 0) 1513 return (0); 1514 } 1515 } 1516 1517 return (ERR_NO_BOOTPATH); 1518 } 1519 1520 /* 1521 * Check the disk label information and retrieve needed vdev name-value pairs. 1522 * 1523 * Return: 1524 * 0 - success 1525 * ERR_* - failure 1526 */ 1527 static int 1528 check_pool_label(uint64_t sector, char *stack, char *outdevid, 1529 char *outpath, uint64_t *outguid, uint64_t *outashift, uint64_t *outversion) 1530 { 1531 vdev_phys_t *vdev; 1532 uint64_t pool_state, txg = 0; 1533 char *nvlist, *nv, *features; 1534 uint64_t diskguid; 1535 1536 sector += (VDEV_SKIP_SIZE >> SPA_MINBLOCKSHIFT); 1537 1538 /* Read in the vdev name-value pair list (112K). */ 1539 if (devread(sector, 0, VDEV_PHYS_SIZE, stack) == 0) 1540 return (ERR_READ); 1541 1542 vdev = (vdev_phys_t *)stack; 1543 stack += sizeof (vdev_phys_t); 1544 1545 if (nvlist_unpack(vdev->vp_nvlist, &nvlist)) 1546 return (ERR_FSYS_CORRUPT); 1547 1548 if (nvlist_lookup_value(nvlist, ZPOOL_CONFIG_POOL_STATE, &pool_state, 1549 DATA_TYPE_UINT64, NULL)) 1550 return (ERR_FSYS_CORRUPT); 1551 1552 if (pool_state == POOL_STATE_DESTROYED) 1553 return (ERR_FILESYSTEM_NOT_FOUND); 1554 1555 if (nvlist_lookup_value(nvlist, ZPOOL_CONFIG_POOL_NAME, 1556 current_rootpool, DATA_TYPE_STRING, NULL)) 1557 return (ERR_FSYS_CORRUPT); 1558 1559 if (nvlist_lookup_value(nvlist, ZPOOL_CONFIG_POOL_TXG, &txg, 1560 DATA_TYPE_UINT64, NULL)) 1561 return (ERR_FSYS_CORRUPT); 1562 1563 /* not an active device */ 1564 if (txg == 0) 1565 return (ERR_NO_BOOTPATH); 1566 1567 if (nvlist_lookup_value(nvlist, ZPOOL_CONFIG_VERSION, outversion, 1568 DATA_TYPE_UINT64, NULL)) 1569 return (ERR_FSYS_CORRUPT); 1570 if (!SPA_VERSION_IS_SUPPORTED(*outversion)) 1571 return (ERR_NEWER_VERSION); 1572 if (nvlist_lookup_value(nvlist, ZPOOL_CONFIG_VDEV_TREE, &nv, 1573 DATA_TYPE_NVLIST, NULL)) 1574 return (ERR_FSYS_CORRUPT); 1575 if (nvlist_lookup_value(nvlist, ZPOOL_CONFIG_GUID, &diskguid, 1576 DATA_TYPE_UINT64, NULL)) 1577 return (ERR_FSYS_CORRUPT); 1578 if (nvlist_lookup_value(nv, ZPOOL_CONFIG_ASHIFT, outashift, 1579 DATA_TYPE_UINT64, NULL) != 0) 1580 return (ERR_FSYS_CORRUPT); 1581 if (vdev_get_bootpath(nv, diskguid, outdevid, outpath, 0)) 1582 return (ERR_NO_BOOTPATH); 1583 if (nvlist_lookup_value(nvlist, ZPOOL_CONFIG_POOL_GUID, outguid, 1584 DATA_TYPE_UINT64, NULL)) 1585 return (ERR_FSYS_CORRUPT); 1586 1587 if (nvlist_lookup_value(nvlist, ZPOOL_CONFIG_FEATURES_FOR_READ, 1588 &features, DATA_TYPE_NVLIST, NULL) == 0) { 1589 char *nvp; 1590 char *name = stack; 1591 stack += MAXNAMELEN; 1592 1593 for (nvp = nvlist_next_nvpair(features, NULL); 1594 nvp != NULL; 1595 nvp = nvlist_next_nvpair(features, nvp)) { 1596 zap_attribute_t za; 1597 1598 if (nvpair_name(nvp, name, MAXNAMELEN) != 0) 1599 return (ERR_FSYS_CORRUPT); 1600 1601 za.za_integer_length = 8; 1602 za.za_num_integers = 1; 1603 za.za_first_integer = 1; 1604 za.za_name = name; 1605 if (check_feature(&za, spa_feature_names, stack) != 0) 1606 return (ERR_NEWER_VERSION); 1607 } 1608 } 1609 1610 return (0); 1611 } 1612 1613 /* 1614 * zfs_mount() locates a valid uberblock of the root pool and read in its MOS 1615 * to the memory address MOS. 1616 * 1617 * Return: 1618 * 1 - success 1619 * 0 - failure 1620 */ 1621 int 1622 zfs_mount(void) 1623 { 1624 char *stack, *ub_array; 1625 int label = 0; 1626 uberblock_t *ubbest; 1627 objset_phys_t *osp; 1628 char tmp_bootpath[MAXNAMELEN]; 1629 char tmp_devid[MAXNAMELEN]; 1630 uint64_t tmp_guid, ashift, version; 1631 uint64_t adjpl = (uint64_t)part_length << SPA_MINBLOCKSHIFT; 1632 int err = errnum; /* preserve previous errnum state */ 1633 1634 /* if it's our first time here, zero the best uberblock out */ 1635 if (best_drive == 0 && best_part == 0 && find_best_root) { 1636 grub_memset(¤t_uberblock, 0, sizeof (uberblock_t)); 1637 pool_guid = 0; 1638 } 1639 1640 stackbase = ZFS_SCRATCH; 1641 stack = stackbase; 1642 ub_array = stack; 1643 stack += VDEV_UBERBLOCK_RING; 1644 1645 osp = (objset_phys_t *)stack; 1646 stack += sizeof (objset_phys_t); 1647 adjpl = P2ALIGN(adjpl, (uint64_t)sizeof (vdev_label_t)); 1648 1649 for (label = 0; label < VDEV_LABELS; label++) { 1650 1651 /* 1652 * some eltorito stacks don't give us a size and 1653 * we end up setting the size to MAXUINT, further 1654 * some of these devices stop working once a single 1655 * read past the end has been issued. Checking 1656 * for a maximum part_length and skipping the backup 1657 * labels at the end of the slice/partition/device 1658 * avoids breaking down on such devices. 1659 */ 1660 if (part_length == MAXUINT && label == 2) 1661 break; 1662 1663 uint64_t sector = vdev_label_start(adjpl, 1664 label) >> SPA_MINBLOCKSHIFT; 1665 1666 /* Read in the uberblock ring (128K). */ 1667 if (devread(sector + 1668 ((VDEV_SKIP_SIZE + VDEV_PHYS_SIZE) >> SPA_MINBLOCKSHIFT), 1669 0, VDEV_UBERBLOCK_RING, ub_array) == 0) 1670 continue; 1671 1672 if (check_pool_label(sector, stack, tmp_devid, 1673 tmp_bootpath, &tmp_guid, &ashift, &version)) 1674 continue; 1675 1676 if (pool_guid == 0) 1677 pool_guid = tmp_guid; 1678 1679 if ((ubbest = find_bestub(ub_array, ashift, sector)) == NULL || 1680 zio_read(&ubbest->ub_rootbp, osp, stack) != 0) 1681 continue; 1682 1683 VERIFY_OS_TYPE(osp, DMU_OST_META); 1684 1685 if (version >= SPA_VERSION_FEATURES && 1686 check_mos_features(&osp->os_meta_dnode, stack) != 0) 1687 continue; 1688 1689 if (find_best_root && ((pool_guid != tmp_guid) || 1690 vdev_uberblock_compare(ubbest, &(current_uberblock)) <= 0)) 1691 continue; 1692 1693 /* Got the MOS. Save it at the memory addr MOS. */ 1694 grub_memmove(MOS, &osp->os_meta_dnode, DNODE_SIZE); 1695 grub_memmove(¤t_uberblock, ubbest, sizeof (uberblock_t)); 1696 grub_memmove(current_bootpath, tmp_bootpath, MAXNAMELEN); 1697 grub_memmove(current_devid, tmp_devid, grub_strlen(tmp_devid)); 1698 is_zfs_mount = 1; 1699 return (1); 1700 } 1701 1702 /* 1703 * While some fs impls. (tftp) rely on setting and keeping 1704 * global errnums set, others won't reset it and will break 1705 * when issuing rawreads. The goal here is to simply not 1706 * have zfs mount attempts impact the previous state. 1707 */ 1708 errnum = err; 1709 return (0); 1710 } 1711 1712 /* 1713 * zfs_open() locates a file in the rootpool by following the 1714 * MOS and places the dnode of the file in the memory address DNODE. 1715 * 1716 * Return: 1717 * 1 - success 1718 * 0 - failure 1719 */ 1720 int 1721 zfs_open(char *filename) 1722 { 1723 char *stack; 1724 dnode_phys_t *mdn; 1725 1726 file_buf = NULL; 1727 stackbase = ZFS_SCRATCH; 1728 stack = stackbase; 1729 1730 mdn = (dnode_phys_t *)stack; 1731 stack += sizeof (dnode_phys_t); 1732 1733 dnode_mdn = NULL; 1734 dnode_buf = (dnode_phys_t *)stack; 1735 stack += 1<<DNODE_BLOCK_SHIFT; 1736 1737 /* 1738 * menu.lst is placed at the root pool filesystem level, 1739 * do not goto 'current_bootfs'. 1740 */ 1741 if (is_top_dataset_file(filename)) { 1742 if (errnum = get_objset_mdn(MOS, NULL, NULL, mdn, stack)) 1743 return (0); 1744 1745 current_bootfs_obj = 0; 1746 } else { 1747 if (current_bootfs[0] == '\0') { 1748 /* Get the default root filesystem object number */ 1749 if (errnum = get_default_bootfsobj(MOS, 1750 ¤t_bootfs_obj, stack)) 1751 return (0); 1752 1753 if (errnum = get_objset_mdn(MOS, NULL, 1754 ¤t_bootfs_obj, mdn, stack)) 1755 return (0); 1756 } else { 1757 if (errnum = get_objset_mdn(MOS, current_bootfs, 1758 ¤t_bootfs_obj, mdn, stack)) { 1759 grub_memset(current_bootfs, 0, MAXNAMELEN); 1760 return (0); 1761 } 1762 } 1763 } 1764 1765 if (dnode_get_path(mdn, filename, DNODE, stack)) { 1766 errnum = ERR_FILE_NOT_FOUND; 1767 return (0); 1768 } 1769 1770 /* get the file size and set the file position to 0 */ 1771 1772 /* 1773 * For DMU_OT_SA we will need to locate the SIZE attribute 1774 * attribute, which could be either in the bonus buffer 1775 * or the "spill" block. 1776 */ 1777 if (DNODE->dn_bonustype == DMU_OT_SA) { 1778 sa_hdr_phys_t *sahdrp; 1779 int hdrsize; 1780 1781 if (DNODE->dn_bonuslen != 0) { 1782 sahdrp = (sa_hdr_phys_t *)DN_BONUS(DNODE); 1783 } else { 1784 if (DNODE->dn_flags & DNODE_FLAG_SPILL_BLKPTR) { 1785 blkptr_t *bp = &DNODE->dn_spill; 1786 void *buf; 1787 1788 buf = (void *)stack; 1789 stack += BP_GET_LSIZE(bp); 1790 1791 /* reset errnum to rawread() failure */ 1792 errnum = 0; 1793 if (zio_read(bp, buf, stack) != 0) { 1794 return (0); 1795 } 1796 sahdrp = buf; 1797 } else { 1798 errnum = ERR_FSYS_CORRUPT; 1799 return (0); 1800 } 1801 } 1802 hdrsize = SA_HDR_SIZE(sahdrp); 1803 filemax = *(uint64_t *)((char *)sahdrp + hdrsize + 1804 SA_SIZE_OFFSET); 1805 } else { 1806 filemax = ((znode_phys_t *)DN_BONUS(DNODE))->zp_size; 1807 } 1808 filepos = 0; 1809 1810 dnode_buf = NULL; 1811 return (1); 1812 } 1813 1814 /* 1815 * zfs_read reads in the data blocks pointed by the DNODE. 1816 * 1817 * Return: 1818 * len - the length successfully read in to the buffer 1819 * 0 - failure 1820 */ 1821 int 1822 zfs_read(char *buf, int len) 1823 { 1824 char *stack; 1825 int blksz, length, movesize; 1826 1827 if (file_buf == NULL) { 1828 file_buf = stackbase; 1829 stackbase += SPA_MAXBLOCKSIZE; 1830 file_start = file_end = 0; 1831 } 1832 stack = stackbase; 1833 1834 /* 1835 * If offset is in memory, move it into the buffer provided and return. 1836 */ 1837 if (filepos >= file_start && filepos+len <= file_end) { 1838 grub_memmove(buf, file_buf + filepos - file_start, len); 1839 filepos += len; 1840 return (len); 1841 } 1842 1843 blksz = DNODE->dn_datablkszsec << SPA_MINBLOCKSHIFT; 1844 1845 /* 1846 * Note: for GRUB, SPA_MAXBLOCKSIZE is 128KB. There is not enough 1847 * memory to allocate the new max blocksize (16MB), so while 1848 * GRUB understands the large_blocks on-disk feature, it can't 1849 * actually read large blocks. 1850 */ 1851 if (blksz > SPA_MAXBLOCKSIZE) { 1852 grub_printf("blocks larger than 128K are not supported\n"); 1853 return (0); 1854 } 1855 1856 /* 1857 * Entire Dnode is too big to fit into the space available. We 1858 * will need to read it in chunks. This could be optimized to 1859 * read in as large a chunk as there is space available, but for 1860 * now, this only reads in one data block at a time. 1861 */ 1862 length = len; 1863 while (length) { 1864 /* 1865 * Find requested blkid and the offset within that block. 1866 */ 1867 uint64_t blkid = filepos / blksz; 1868 1869 if (errnum = dmu_read(DNODE, blkid, file_buf, stack)) 1870 return (0); 1871 1872 file_start = blkid * blksz; 1873 file_end = file_start + blksz; 1874 1875 movesize = MIN(length, file_end - filepos); 1876 1877 grub_memmove(buf, file_buf + filepos - file_start, 1878 movesize); 1879 buf += movesize; 1880 length -= movesize; 1881 filepos += movesize; 1882 } 1883 1884 return (len); 1885 } 1886 1887 /* 1888 * No-Op 1889 */ 1890 int 1891 zfs_embed(int *start_sector, int needed_sectors) 1892 { 1893 return (1); 1894 } 1895 1896 #endif /* FSYS_ZFS */ 1897