1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2017, Fedor Uporov 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 * 28 * $FreeBSD$ 29 */ 30 31 #include <sys/param.h> 32 #include <sys/systm.h> 33 #include <sys/types.h> 34 #include <sys/sdt.h> 35 #include <sys/stat.h> 36 #include <sys/kernel.h> 37 #include <sys/malloc.h> 38 #include <sys/vnode.h> 39 #include <sys/bio.h> 40 #include <sys/buf.h> 41 #include <sys/endian.h> 42 #include <sys/conf.h> 43 #include <sys/gsb_crc32.h> 44 #include <sys/mount.h> 45 46 #include <fs/ext2fs/fs.h> 47 #include <fs/ext2fs/ext2fs.h> 48 #include <fs/ext2fs/ext2_dinode.h> 49 #include <fs/ext2fs/inode.h> 50 #include <fs/ext2fs/ext2_dir.h> 51 #include <fs/ext2fs/htree.h> 52 #include <fs/ext2fs/ext2_extattr.h> 53 #include <fs/ext2fs/ext2_extern.h> 54 55 SDT_PROVIDER_DECLARE(ext2fs); 56 /* 57 * ext2fs trace probe: 58 * arg0: verbosity. Higher numbers give more verbose messages 59 * arg1: Textual message 60 */ 61 SDT_PROBE_DEFINE2(ext2fs, , trace, csum, "int", "char*"); 62 63 #define EXT2_BG_INODE_BITMAP_CSUM_HI_END \ 64 (offsetof(struct ext2_gd, ext4bgd_i_bmap_csum_hi) + \ 65 sizeof(uint16_t)) 66 67 #define EXT2_INODE_CSUM_HI_EXTRA_END \ 68 (offsetof(struct ext2fs_dinode, e2di_chksum_hi) + sizeof(uint16_t) - \ 69 E2FS_REV0_INODE_SIZE) 70 71 #define EXT2_BG_BLOCK_BITMAP_CSUM_HI_LOCATION \ 72 (offsetof(struct ext2_gd, ext4bgd_b_bmap_csum_hi) + \ 73 sizeof(uint16_t)) 74 75 void 76 ext2_sb_csum_set_seed(struct m_ext2fs *fs) 77 { 78 79 if (EXT2_HAS_INCOMPAT_FEATURE(fs, EXT2F_INCOMPAT_CSUM_SEED)) 80 fs->e2fs_csum_seed = le32toh(fs->e2fs->e4fs_chksum_seed); 81 else if (EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT2F_ROCOMPAT_METADATA_CKSUM)) { 82 fs->e2fs_csum_seed = calculate_crc32c(~0, fs->e2fs->e2fs_uuid, 83 sizeof(fs->e2fs->e2fs_uuid)); 84 } 85 else 86 fs->e2fs_csum_seed = 0; 87 } 88 89 int 90 ext2_sb_csum_verify(struct m_ext2fs *fs) 91 { 92 93 if (fs->e2fs->e4fs_chksum_type != EXT4_CRC32C_CHKSUM) { 94 printf( 95 "WARNING: mount of %s denied due bad sb csum type\n", fs->e2fs_fsmnt); 96 return (EINVAL); 97 } 98 if (le32toh(fs->e2fs->e4fs_sbchksum) != 99 calculate_crc32c(~0, (const char *)fs->e2fs, 100 offsetof(struct ext2fs, e4fs_sbchksum))) { 101 printf( 102 "WARNING: mount of %s denied due bad sb csum=0x%x, expected=0x%x - run fsck\n", 103 fs->e2fs_fsmnt, le32toh(fs->e2fs->e4fs_sbchksum), 104 calculate_crc32c(~0, (const char *)fs->e2fs, 105 offsetof(struct ext2fs, e4fs_sbchksum))); 106 return (EINVAL); 107 } 108 109 return (0); 110 } 111 112 void 113 ext2_sb_csum_set(struct m_ext2fs *fs) 114 { 115 116 fs->e2fs->e4fs_sbchksum = 117 htole32(calculate_crc32c(~0, (const char *)fs->e2fs, 118 offsetof(struct ext2fs, e4fs_sbchksum))); 119 } 120 121 static uint32_t 122 ext2_extattr_blk_csum(struct inode *ip, uint64_t facl, 123 struct ext2fs_extattr_header *header) 124 { 125 struct m_ext2fs *fs; 126 uint32_t crc, dummy_crc = 0; 127 uint64_t facl_bn = htole64(facl); 128 int offset = offsetof(struct ext2fs_extattr_header, h_checksum); 129 130 fs = ip->i_e2fs; 131 132 crc = calculate_crc32c(fs->e2fs_csum_seed, (uint8_t *)&facl_bn, 133 sizeof(facl_bn)); 134 crc = calculate_crc32c(crc, (uint8_t *)header, offset); 135 crc = calculate_crc32c(crc, (uint8_t *)&dummy_crc, 136 sizeof(dummy_crc)); 137 offset += sizeof(dummy_crc); 138 crc = calculate_crc32c(crc, (uint8_t *)header + offset, 139 fs->e2fs_bsize - offset); 140 141 return (htole32(crc)); 142 } 143 144 int 145 ext2_extattr_blk_csum_verify(struct inode *ip, struct buf *bp) 146 { 147 struct ext2fs_extattr_header *header; 148 149 header = (struct ext2fs_extattr_header *)bp->b_data; 150 151 if (EXT2_HAS_RO_COMPAT_FEATURE(ip->i_e2fs, EXT2F_ROCOMPAT_METADATA_CKSUM) && 152 (header->h_checksum != ext2_extattr_blk_csum(ip, ip->i_facl, header))) { 153 SDT_PROBE2(ext2fs, , trace, csum, 1, "bad extattr csum detected"); 154 return (EIO); 155 } 156 157 return (0); 158 } 159 160 void 161 ext2_extattr_blk_csum_set(struct inode *ip, struct buf *bp) 162 { 163 struct ext2fs_extattr_header *header; 164 165 if (!EXT2_HAS_RO_COMPAT_FEATURE(ip->i_e2fs, EXT2F_ROCOMPAT_METADATA_CKSUM)) 166 return; 167 168 header = (struct ext2fs_extattr_header *)bp->b_data; 169 header->h_checksum = ext2_extattr_blk_csum(ip, ip->i_facl, header); 170 } 171 172 void 173 ext2_init_dirent_tail(struct ext2fs_direct_tail *tp) 174 { 175 memset(tp, 0, sizeof(struct ext2fs_direct_tail)); 176 tp->e2dt_rec_len = le16toh(sizeof(struct ext2fs_direct_tail)); 177 tp->e2dt_reserved_ft = EXT2_FT_DIR_CSUM; 178 } 179 180 int 181 ext2_is_dirent_tail(struct inode *ip, struct ext2fs_direct_2 *ep) 182 { 183 struct m_ext2fs *fs; 184 struct ext2fs_direct_tail *tp; 185 186 fs = ip->i_e2fs; 187 188 if (!EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT2F_ROCOMPAT_METADATA_CKSUM)) 189 return (0); 190 191 tp = (struct ext2fs_direct_tail *)ep; 192 if (tp->e2dt_reserved_zero1 == 0 && 193 le16toh(tp->e2dt_rec_len) == sizeof(struct ext2fs_direct_tail) && 194 tp->e2dt_reserved_zero2 == 0 && 195 tp->e2dt_reserved_ft == EXT2_FT_DIR_CSUM) 196 return (1); 197 198 return (0); 199 } 200 201 struct ext2fs_direct_tail * 202 ext2_dirent_get_tail(struct inode *ip, struct ext2fs_direct_2 *ep) 203 { 204 struct ext2fs_direct_2 *dep; 205 void *top; 206 unsigned int rec_len; 207 208 dep = ep; 209 top = EXT2_DIRENT_TAIL(ep, ip->i_e2fs->e2fs_bsize); 210 rec_len = le16toh(dep->e2d_reclen); 211 212 while (rec_len && !(rec_len & 0x3)) { 213 dep = (struct ext2fs_direct_2 *)(((char *)dep) + rec_len); 214 if ((void *)dep >= top) 215 break; 216 rec_len = le16toh(dep->e2d_reclen); 217 } 218 219 if (dep != top) 220 return (NULL); 221 222 if (ext2_is_dirent_tail(ip, dep)) 223 return ((struct ext2fs_direct_tail *)dep); 224 225 return (NULL); 226 } 227 228 static uint32_t 229 ext2_dirent_csum(struct inode *ip, struct ext2fs_direct_2 *ep, int size) 230 { 231 struct m_ext2fs *fs; 232 char *buf; 233 uint32_t inum, gen, crc; 234 235 fs = ip->i_e2fs; 236 237 buf = (char *)ep; 238 239 inum = htole32(ip->i_number); 240 gen = htole32(ip->i_gen); 241 crc = calculate_crc32c(fs->e2fs_csum_seed, (uint8_t *)&inum, sizeof(inum)); 242 crc = calculate_crc32c(crc, (uint8_t *)&gen, sizeof(gen)); 243 crc = calculate_crc32c(crc, (uint8_t *)buf, size); 244 245 return (crc); 246 } 247 248 int 249 ext2_dirent_csum_verify(struct inode *ip, struct ext2fs_direct_2 *ep) 250 { 251 uint32_t calculated; 252 struct ext2fs_direct_tail *tp; 253 254 tp = ext2_dirent_get_tail(ip, ep); 255 if (tp == NULL) 256 return (0); 257 258 calculated = ext2_dirent_csum(ip, ep, (char *)tp - (char *)ep); 259 if (calculated != le32toh(tp->e2dt_checksum)) 260 return (EIO); 261 262 return (0); 263 } 264 265 static struct ext2fs_htree_count * 266 ext2_get_dx_count(struct inode *ip, struct ext2fs_direct_2 *ep, int *offset) 267 { 268 struct ext2fs_direct_2 *dp; 269 struct ext2fs_htree_root_info *root; 270 int count_offset; 271 272 if (le16toh(ep->e2d_reclen) == EXT2_BLOCK_SIZE(ip->i_e2fs)) 273 count_offset = 8; 274 else if (le16toh(ep->e2d_reclen) == 12) { 275 dp = (struct ext2fs_direct_2 *)(((char *)ep) + 12); 276 if (le16toh(dp->e2d_reclen) != EXT2_BLOCK_SIZE(ip->i_e2fs) - 12) 277 return (NULL); 278 279 root = (struct ext2fs_htree_root_info *)(((char *)dp + 12)); 280 if (root->h_reserved1 || 281 root->h_info_len != sizeof(struct ext2fs_htree_root_info)) 282 return (NULL); 283 284 count_offset = 32; 285 } else 286 return (NULL); 287 288 if (offset) 289 *offset = count_offset; 290 291 return ((struct ext2fs_htree_count *)(((char *)ep) + count_offset)); 292 } 293 294 static uint32_t 295 ext2_dx_csum(struct inode *ip, struct ext2fs_direct_2 *ep, int count_offset, 296 int count, struct ext2fs_htree_tail *tp) 297 { 298 struct m_ext2fs *fs; 299 char *buf; 300 int size; 301 uint32_t inum, old_csum, gen, crc; 302 303 fs = ip->i_e2fs; 304 305 buf = (char *)ep; 306 307 size = count_offset + (count * sizeof(struct ext2fs_htree_entry)); 308 old_csum = tp->ht_checksum; 309 tp->ht_checksum = 0; 310 311 inum = htole32(ip->i_number); 312 gen = htole32(ip->i_gen); 313 crc = calculate_crc32c(fs->e2fs_csum_seed, (uint8_t *)&inum, sizeof(inum)); 314 crc = calculate_crc32c(crc, (uint8_t *)&gen, sizeof(gen)); 315 crc = calculate_crc32c(crc, (uint8_t *)buf, size); 316 crc = calculate_crc32c(crc, (uint8_t *)tp, sizeof(struct ext2fs_htree_tail)); 317 tp->ht_checksum = old_csum; 318 319 return htole32(crc); 320 } 321 322 int 323 ext2_dx_csum_verify(struct inode *ip, struct ext2fs_direct_2 *ep) 324 { 325 uint32_t calculated; 326 struct ext2fs_htree_count *cp; 327 struct ext2fs_htree_tail *tp; 328 int count_offset, limit, count; 329 330 cp = ext2_get_dx_count(ip, ep, &count_offset); 331 if (cp == NULL) 332 return (0); 333 334 limit = le16toh(cp->h_entries_max); 335 count = le16toh(cp->h_entries_num); 336 if (count_offset + (limit * sizeof(struct ext2fs_htree_entry)) > 337 ip->i_e2fs->e2fs_bsize - sizeof(struct ext2fs_htree_tail)) 338 return (EIO); 339 340 tp = (struct ext2fs_htree_tail *)(((struct ext2fs_htree_entry *)cp) + limit); 341 calculated = ext2_dx_csum(ip, ep, count_offset, count, tp); 342 343 if (tp->ht_checksum != calculated) 344 return (EIO); 345 346 return (0); 347 } 348 349 int 350 ext2_dir_blk_csum_verify(struct inode *ip, struct buf *bp) 351 { 352 struct m_ext2fs *fs; 353 struct ext2fs_direct_2 *ep; 354 int error = 0; 355 356 fs = ip->i_e2fs; 357 358 if (!EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT2F_ROCOMPAT_METADATA_CKSUM)) 359 return (error); 360 361 ep = (struct ext2fs_direct_2 *)bp->b_data; 362 363 if (ext2_dirent_get_tail(ip, ep) != NULL) 364 error = ext2_dirent_csum_verify(ip, ep); 365 else if (ext2_get_dx_count(ip, ep, NULL) != NULL) 366 error = ext2_dx_csum_verify(ip, ep); 367 368 if (error) 369 SDT_PROBE2(ext2fs, , trace, csum, 1, "bad directory csum detected"); 370 371 return (error); 372 } 373 374 void 375 ext2_dirent_csum_set(struct inode *ip, struct ext2fs_direct_2 *ep) 376 { 377 struct m_ext2fs *fs; 378 struct ext2fs_direct_tail *tp; 379 380 fs = ip->i_e2fs; 381 382 if (!EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT2F_ROCOMPAT_METADATA_CKSUM)) 383 return; 384 385 tp = ext2_dirent_get_tail(ip, ep); 386 if (tp == NULL) 387 return; 388 389 tp->e2dt_checksum = 390 htole32(ext2_dirent_csum(ip, ep, (char *)tp - (char *)ep)); 391 } 392 393 void 394 ext2_dx_csum_set(struct inode *ip, struct ext2fs_direct_2 *ep) 395 { 396 struct m_ext2fs *fs; 397 struct ext2fs_htree_count *cp; 398 struct ext2fs_htree_tail *tp; 399 int count_offset, limit, count; 400 401 fs = ip->i_e2fs; 402 403 if (!EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT2F_ROCOMPAT_METADATA_CKSUM)) 404 return; 405 406 cp = ext2_get_dx_count(ip, ep, &count_offset); 407 if (cp == NULL) 408 return; 409 410 limit = le16toh(cp->h_entries_max); 411 count = le16toh(cp->h_entries_num); 412 if (count_offset + (limit * sizeof(struct ext2fs_htree_entry)) > 413 ip->i_e2fs->e2fs_bsize - sizeof(struct ext2fs_htree_tail)) 414 return; 415 416 tp = (struct ext2fs_htree_tail *)(((struct ext2fs_htree_entry *)cp) + limit); 417 tp->ht_checksum = ext2_dx_csum(ip, ep, count_offset, count, tp); 418 } 419 420 static uint32_t 421 ext2_extent_blk_csum(struct inode *ip, struct ext4_extent_header *ehp) 422 { 423 struct m_ext2fs *fs; 424 size_t size; 425 uint32_t inum, gen, crc; 426 427 fs = ip->i_e2fs; 428 429 size = EXT4_EXTENT_TAIL_OFFSET(ehp) + 430 offsetof(struct ext4_extent_tail, et_checksum); 431 432 inum = htole32(ip->i_number); 433 gen = htole32(ip->i_gen); 434 crc = calculate_crc32c(fs->e2fs_csum_seed, (uint8_t *)&inum, sizeof(inum)); 435 crc = calculate_crc32c(crc, (uint8_t *)&gen, sizeof(gen)); 436 crc = calculate_crc32c(crc, (uint8_t *)ehp, size); 437 438 return (crc); 439 } 440 441 int 442 ext2_extent_blk_csum_verify(struct inode *ip, void *data) 443 { 444 struct m_ext2fs *fs; 445 struct ext4_extent_header *ehp; 446 struct ext4_extent_tail *etp; 447 uint32_t provided, calculated; 448 449 fs = ip->i_e2fs; 450 451 if (!EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT2F_ROCOMPAT_METADATA_CKSUM)) 452 return (0); 453 454 ehp = (struct ext4_extent_header *)data; 455 etp = (struct ext4_extent_tail *)(((char *)ehp) + 456 EXT4_EXTENT_TAIL_OFFSET(ehp)); 457 458 provided = le32toh(etp->et_checksum); 459 calculated = ext2_extent_blk_csum(ip, ehp); 460 461 if (provided != calculated) { 462 SDT_PROBE2(ext2fs, , trace, csum, 1, "bad extent csum detected"); 463 return (EIO); 464 } 465 466 return (0); 467 } 468 469 void 470 ext2_extent_blk_csum_set(struct inode *ip, void *data) 471 { 472 struct m_ext2fs *fs; 473 struct ext4_extent_header *ehp; 474 struct ext4_extent_tail *etp; 475 476 fs = ip->i_e2fs; 477 478 if (!EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT2F_ROCOMPAT_METADATA_CKSUM)) 479 return; 480 481 ehp = (struct ext4_extent_header *)data; 482 etp = (struct ext4_extent_tail *)(((char *)data) + 483 EXT4_EXTENT_TAIL_OFFSET(ehp)); 484 485 etp->et_checksum = htole32(ext2_extent_blk_csum(ip, 486 (struct ext4_extent_header *)data)); 487 } 488 489 int 490 ext2_gd_i_bitmap_csum_verify(struct m_ext2fs *fs, int cg, struct buf *bp) 491 { 492 uint32_t hi, provided, calculated; 493 494 if (!EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT2F_ROCOMPAT_METADATA_CKSUM)) 495 return (0); 496 497 provided = le16toh(fs->e2fs_gd[cg].ext4bgd_i_bmap_csum); 498 calculated = calculate_crc32c(fs->e2fs_csum_seed, bp->b_data, 499 fs->e2fs_ipg / 8); 500 if (le16toh(fs->e2fs->e3fs_desc_size) >= 501 EXT2_BG_INODE_BITMAP_CSUM_HI_END) { 502 hi = le16toh(fs->e2fs_gd[cg].ext4bgd_i_bmap_csum_hi); 503 provided |= (hi << 16); 504 } else 505 calculated &= 0xFFFF; 506 507 if (provided != calculated) { 508 SDT_PROBE2(ext2fs, , trace, csum, 1, "bad inode bitmap csum detected"); 509 return (EIO); 510 } 511 512 return (0); 513 } 514 515 void 516 ext2_gd_i_bitmap_csum_set(struct m_ext2fs *fs, int cg, struct buf *bp) 517 { 518 uint32_t csum; 519 520 if (!EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT2F_ROCOMPAT_METADATA_CKSUM)) 521 return; 522 523 csum = calculate_crc32c(fs->e2fs_csum_seed, bp->b_data, 524 fs->e2fs_ipg / 8); 525 fs->e2fs_gd[cg].ext4bgd_i_bmap_csum = htole16(csum & 0xFFFF); 526 if (le16toh(fs->e2fs->e3fs_desc_size) >= EXT2_BG_INODE_BITMAP_CSUM_HI_END) 527 fs->e2fs_gd[cg].ext4bgd_i_bmap_csum_hi = htole16(csum >> 16); 528 } 529 530 int 531 ext2_gd_b_bitmap_csum_verify(struct m_ext2fs *fs, int cg, struct buf *bp) 532 { 533 uint32_t hi, provided, calculated, size; 534 535 if (!EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT2F_ROCOMPAT_METADATA_CKSUM)) 536 return (0); 537 538 size = fs->e2fs_fpg / 8; 539 provided = le16toh(fs->e2fs_gd[cg].ext4bgd_b_bmap_csum); 540 calculated = calculate_crc32c(fs->e2fs_csum_seed, bp->b_data, size); 541 if (le16toh(fs->e2fs->e3fs_desc_size) >= 542 EXT2_BG_BLOCK_BITMAP_CSUM_HI_LOCATION) { 543 hi = le16toh(fs->e2fs_gd[cg].ext4bgd_b_bmap_csum_hi); 544 provided |= (hi << 16); 545 } else 546 calculated &= 0xFFFF; 547 548 if (provided != calculated) { 549 SDT_PROBE2(ext2fs, , trace, csum, 1, "bad block bitmap csum detected"); 550 return (EIO); 551 } 552 553 return (0); 554 } 555 556 void 557 ext2_gd_b_bitmap_csum_set(struct m_ext2fs *fs, int cg, struct buf *bp) 558 { 559 uint32_t csum, size; 560 561 if (!EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT2F_ROCOMPAT_METADATA_CKSUM)) 562 return; 563 564 size = fs->e2fs_fpg / 8; 565 csum = calculate_crc32c(fs->e2fs_csum_seed, bp->b_data, size); 566 fs->e2fs_gd[cg].ext4bgd_b_bmap_csum = htole16(csum & 0xFFFF); 567 if (le16toh(fs->e2fs->e3fs_desc_size) >= EXT2_BG_BLOCK_BITMAP_CSUM_HI_LOCATION) 568 fs->e2fs_gd[cg].ext4bgd_b_bmap_csum_hi = htole16(csum >> 16); 569 } 570 571 static uint32_t 572 ext2_ei_csum(struct inode *ip, struct ext2fs_dinode *ei) 573 { 574 struct m_ext2fs *fs; 575 uint32_t inode_csum_seed, inum, gen, crc; 576 uint16_t dummy_csum = 0; 577 unsigned int offset, csum_size; 578 579 fs = ip->i_e2fs; 580 offset = offsetof(struct ext2fs_dinode, e2di_chksum_lo); 581 csum_size = sizeof(dummy_csum); 582 inum = htole32(ip->i_number); 583 crc = calculate_crc32c(fs->e2fs_csum_seed, 584 (uint8_t *)&inum, sizeof(inum)); 585 gen = htole32(ip->i_gen); 586 inode_csum_seed = calculate_crc32c(crc, 587 (uint8_t *)&gen, sizeof(gen)); 588 589 crc = calculate_crc32c(inode_csum_seed, (uint8_t *)ei, offset); 590 crc = calculate_crc32c(crc, (uint8_t *)&dummy_csum, csum_size); 591 offset += csum_size; 592 crc = calculate_crc32c(crc, (uint8_t *)ei + offset, 593 E2FS_REV0_INODE_SIZE - offset); 594 595 if (EXT2_INODE_SIZE(fs) > E2FS_REV0_INODE_SIZE) { 596 offset = offsetof(struct ext2fs_dinode, e2di_chksum_hi); 597 crc = calculate_crc32c(crc, (uint8_t *)ei + 598 E2FS_REV0_INODE_SIZE, offset - E2FS_REV0_INODE_SIZE); 599 600 if ((EXT2_INODE_SIZE(ip->i_e2fs) > E2FS_REV0_INODE_SIZE && 601 le16toh(ei->e2di_extra_isize) >= 602 EXT2_INODE_CSUM_HI_EXTRA_END)) { 603 crc = calculate_crc32c(crc, (uint8_t *)&dummy_csum, 604 csum_size); 605 offset += csum_size; 606 } 607 608 crc = calculate_crc32c(crc, (uint8_t *)ei + offset, 609 EXT2_INODE_SIZE(fs) - offset); 610 } 611 612 return (crc); 613 } 614 615 int 616 ext2_ei_csum_verify(struct inode *ip, struct ext2fs_dinode *ei) 617 { 618 struct m_ext2fs *fs; 619 const static struct ext2fs_dinode ei_zero; 620 uint32_t hi, provided, calculated; 621 622 fs = ip->i_e2fs; 623 624 if (!EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT2F_ROCOMPAT_METADATA_CKSUM)) 625 return (0); 626 627 provided = le16toh(ei->e2di_chksum_lo); 628 calculated = ext2_ei_csum(ip, ei); 629 630 if ((EXT2_INODE_SIZE(fs) > E2FS_REV0_INODE_SIZE && 631 le16toh(ei->e2di_extra_isize) >= EXT2_INODE_CSUM_HI_EXTRA_END)) { 632 hi = le16toh(ei->e2di_chksum_hi); 633 provided |= hi << 16; 634 } else 635 calculated &= 0xFFFF; 636 637 if (provided != calculated) { 638 /* 639 * If it is first time used dinode, 640 * it is expected that it will be zeroed 641 * and we will not return checksum error in this case. 642 */ 643 if (!memcmp(ei, &ei_zero, sizeof(struct ext2fs_dinode))) 644 return (0); 645 646 SDT_PROBE2(ext2fs, , trace, csum, 1, "bad inode csum"); 647 648 return (EIO); 649 } 650 651 return (0); 652 } 653 654 void 655 ext2_ei_csum_set(struct inode *ip, struct ext2fs_dinode *ei) 656 { 657 struct m_ext2fs *fs; 658 uint32_t crc; 659 660 fs = ip->i_e2fs; 661 662 if (!EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT2F_ROCOMPAT_METADATA_CKSUM)) 663 return; 664 665 crc = ext2_ei_csum(ip, ei); 666 667 ei->e2di_chksum_lo = htole16(crc & 0xFFFF); 668 if ((EXT2_INODE_SIZE(fs) > E2FS_REV0_INODE_SIZE && 669 le16toh(ei->e2di_extra_isize) >= EXT2_INODE_CSUM_HI_EXTRA_END)) 670 ei->e2di_chksum_hi = htole16(crc >> 16); 671 } 672 673 static uint16_t 674 ext2_crc16(uint16_t crc, const void *buffer, unsigned int len) 675 { 676 const unsigned char *cp = buffer; 677 /* CRC table for the CRC-16. The poly is 0x8005 (x16 + x15 + x2 + 1). */ 678 static uint16_t const crc16_table[256] = { 679 0x0000, 0xC0C1, 0xC181, 0x0140, 0xC301, 0x03C0, 0x0280, 0xC241, 680 0xC601, 0x06C0, 0x0780, 0xC741, 0x0500, 0xC5C1, 0xC481, 0x0440, 681 0xCC01, 0x0CC0, 0x0D80, 0xCD41, 0x0F00, 0xCFC1, 0xCE81, 0x0E40, 682 0x0A00, 0xCAC1, 0xCB81, 0x0B40, 0xC901, 0x09C0, 0x0880, 0xC841, 683 0xD801, 0x18C0, 0x1980, 0xD941, 0x1B00, 0xDBC1, 0xDA81, 0x1A40, 684 0x1E00, 0xDEC1, 0xDF81, 0x1F40, 0xDD01, 0x1DC0, 0x1C80, 0xDC41, 685 0x1400, 0xD4C1, 0xD581, 0x1540, 0xD701, 0x17C0, 0x1680, 0xD641, 686 0xD201, 0x12C0, 0x1380, 0xD341, 0x1100, 0xD1C1, 0xD081, 0x1040, 687 0xF001, 0x30C0, 0x3180, 0xF141, 0x3300, 0xF3C1, 0xF281, 0x3240, 688 0x3600, 0xF6C1, 0xF781, 0x3740, 0xF501, 0x35C0, 0x3480, 0xF441, 689 0x3C00, 0xFCC1, 0xFD81, 0x3D40, 0xFF01, 0x3FC0, 0x3E80, 0xFE41, 690 0xFA01, 0x3AC0, 0x3B80, 0xFB41, 0x3900, 0xF9C1, 0xF881, 0x3840, 691 0x2800, 0xE8C1, 0xE981, 0x2940, 0xEB01, 0x2BC0, 0x2A80, 0xEA41, 692 0xEE01, 0x2EC0, 0x2F80, 0xEF41, 0x2D00, 0xEDC1, 0xEC81, 0x2C40, 693 0xE401, 0x24C0, 0x2580, 0xE541, 0x2700, 0xE7C1, 0xE681, 0x2640, 694 0x2200, 0xE2C1, 0xE381, 0x2340, 0xE101, 0x21C0, 0x2080, 0xE041, 695 0xA001, 0x60C0, 0x6180, 0xA141, 0x6300, 0xA3C1, 0xA281, 0x6240, 696 0x6600, 0xA6C1, 0xA781, 0x6740, 0xA501, 0x65C0, 0x6480, 0xA441, 697 0x6C00, 0xACC1, 0xAD81, 0x6D40, 0xAF01, 0x6FC0, 0x6E80, 0xAE41, 698 0xAA01, 0x6AC0, 0x6B80, 0xAB41, 0x6900, 0xA9C1, 0xA881, 0x6840, 699 0x7800, 0xB8C1, 0xB981, 0x7940, 0xBB01, 0x7BC0, 0x7A80, 0xBA41, 700 0xBE01, 0x7EC0, 0x7F80, 0xBF41, 0x7D00, 0xBDC1, 0xBC81, 0x7C40, 701 0xB401, 0x74C0, 0x7580, 0xB541, 0x7700, 0xB7C1, 0xB681, 0x7640, 702 0x7200, 0xB2C1, 0xB381, 0x7340, 0xB101, 0x71C0, 0x7080, 0xB041, 703 0x5000, 0x90C1, 0x9181, 0x5140, 0x9301, 0x53C0, 0x5280, 0x9241, 704 0x9601, 0x56C0, 0x5780, 0x9741, 0x5500, 0x95C1, 0x9481, 0x5440, 705 0x9C01, 0x5CC0, 0x5D80, 0x9D41, 0x5F00, 0x9FC1, 0x9E81, 0x5E40, 706 0x5A00, 0x9AC1, 0x9B81, 0x5B40, 0x9901, 0x59C0, 0x5880, 0x9841, 707 0x8801, 0x48C0, 0x4980, 0x8941, 0x4B00, 0x8BC1, 0x8A81, 0x4A40, 708 0x4E00, 0x8EC1, 0x8F81, 0x4F40, 0x8D01, 0x4DC0, 0x4C80, 0x8C41, 709 0x4400, 0x84C1, 0x8581, 0x4540, 0x8701, 0x47C0, 0x4680, 0x8641, 710 0x8201, 0x42C0, 0x4380, 0x8341, 0x4100, 0x81C1, 0x8081, 0x4040 711 }; 712 713 while (len--) 714 crc = (((crc >> 8) & 0xffU) ^ 715 crc16_table[(crc ^ *cp++) & 0xffU]) & 0x0000ffffU; 716 return crc; 717 } 718 719 static uint16_t 720 ext2_gd_csum(struct m_ext2fs *fs, uint32_t block_group, struct ext2_gd *gd) 721 { 722 size_t offset; 723 uint32_t csum32; 724 uint16_t crc, dummy_csum; 725 726 offset = offsetof(struct ext2_gd, ext4bgd_csum); 727 728 block_group = htole32(block_group); 729 730 if (EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT2F_ROCOMPAT_METADATA_CKSUM)) { 731 csum32 = calculate_crc32c(fs->e2fs_csum_seed, 732 (uint8_t *)&block_group, sizeof(block_group)); 733 csum32 = calculate_crc32c(csum32, (uint8_t *)gd, offset); 734 dummy_csum = 0; 735 csum32 = calculate_crc32c(csum32, (uint8_t *)&dummy_csum, 736 sizeof(dummy_csum)); 737 offset += sizeof(dummy_csum); 738 if (offset < le16toh(fs->e2fs->e3fs_desc_size)) 739 csum32 = calculate_crc32c(csum32, (uint8_t *)gd + offset, 740 le16toh(fs->e2fs->e3fs_desc_size) - offset); 741 742 crc = csum32 & 0xFFFF; 743 return (htole16(crc)); 744 } else if (EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT2F_ROCOMPAT_GDT_CSUM)) { 745 crc = ext2_crc16(~0, fs->e2fs->e2fs_uuid, 746 sizeof(fs->e2fs->e2fs_uuid)); 747 crc = ext2_crc16(crc, (uint8_t *)&block_group, 748 sizeof(block_group)); 749 crc = ext2_crc16(crc, (uint8_t *)gd, offset); 750 offset += sizeof(gd->ext4bgd_csum); /* skip checksum */ 751 if (EXT2_HAS_INCOMPAT_FEATURE(fs, EXT2F_INCOMPAT_64BIT) && 752 offset < le16toh(fs->e2fs->e3fs_desc_size)) 753 crc = ext2_crc16(crc, (uint8_t *)gd + offset, 754 le16toh(fs->e2fs->e3fs_desc_size) - offset); 755 return (htole16(crc)); 756 } 757 758 return (0); 759 } 760 761 int 762 ext2_gd_csum_verify(struct m_ext2fs *fs, struct cdev *dev) 763 { 764 unsigned int i; 765 int error = 0; 766 767 for (i = 0; i < fs->e2fs_gcount; i++) { 768 if (fs->e2fs_gd[i].ext4bgd_csum != 769 ext2_gd_csum(fs, i, &fs->e2fs_gd[i])) { 770 printf( 771 "WARNING: mount of %s denied due bad gd=%d csum=0x%x, expected=0x%x - run fsck\n", 772 devtoname(dev), i, fs->e2fs_gd[i].ext4bgd_csum, 773 ext2_gd_csum(fs, i, &fs->e2fs_gd[i])); 774 error = EIO; 775 break; 776 } 777 } 778 779 return (error); 780 } 781 782 void 783 ext2_gd_csum_set(struct m_ext2fs *fs) 784 { 785 unsigned int i; 786 787 for (i = 0; i < fs->e2fs_gcount; i++) 788 fs->e2fs_gd[i].ext4bgd_csum = ext2_gd_csum(fs, i, &fs->e2fs_gd[i]); 789 } 790