debugfs/htree.c

   1 /*
   2  * htree.c --- hash tree routines
   3  *
   4  * Copyright (C) 2002 Theodore Ts'o.  This file may be redistributed
   5  * under the terms of the GNU Public License.
   6  */
   7
   8 #include "config.h"
   9 #include <stdio.h>
  10 #include <unistd.h>
  11 #include <stdlib.h>
  12 #include <ctype.h>
  13 #include <string.h>
  14 #include <time.h>
  15 #ifdef HAVE_ERRNO_H
  16 #include <errno.h>
  17 #endif
  18 #include <sys/types.h>
  19 #ifdef HAVE_GETOPT_H
  20 #include <getopt.h>
  21 #else
  22 extern int optind;
  23 extern char *optarg;
  24 #endif
  25
  26 #include "debugfs.h"
  27 #include "uuid/uuid.h"
  28 #include "e2p/e2p.h"
  29
  30 static FILE *pager;
  31
  32 static void htree_dump_leaf_node(ext2_filsys fs, ext2_ino_t ino,
  33                                  struct ext2_inode *inode,
  34                                  struct ext2_dx_root_info * rootnode,
  35                                  blk64_t blk, char *buf)
  36 {
  37         errcode_t       errcode;
  38         struct ext2_dir_entry *dirent;
  39         int             thislen, col = 0;
  40         unsigned int    offset = 0;
  41         char            name[EXT2_NAME_LEN + 1];
  42         char            tmp[EXT2_NAME_LEN + 64];
  43         blk64_t         pblk;
  44         ext2_dirhash_t  hash, minor_hash;
  45         unsigned int    rec_len;
  46         int             hash_alg;
  47         int             hash_flags = inode->i_flags & EXT4_CASEFOLD_FL;
  48         int             csum_size = 0;
  49
  50         if (ext2fs_has_feature_metadata_csum(fs->super))
  51                 csum_size = sizeof(struct ext2_dir_entry_tail);
  52
  53         errcode = ext2fs_bmap2(fs, ino, inode, buf, 0, blk, 0, &pblk);
  54         if (errcode) {
  55                 com_err("htree_dump_leaf_node", errcode,
  56                         "while mapping logical block %llu\n",
  57                         (unsigned long long) blk);
  58                 return;
  59         }
  60
  61         fprintf(pager, "Reading directory block %llu, phys %llu\n",
  62                 (unsigned long long) blk, (unsigned long long) pblk);
  63         errcode = ext2fs_read_dir_block4(current_fs, pblk, buf, 0, ino);
  64         if (errcode) {
  65                 com_err("htree_dump_leaf_node", errcode,
  66                         "while reading block %llu (%llu)\n",
  67                         (unsigned long long) blk, (unsigned long long) pblk);
  68                 return;
  69         }
  70         hash_alg = rootnode->hash_version;
  71         if ((hash_alg <= EXT2_HASH_TEA) &&
  72             (fs->super->s_flags & EXT2_FLAGS_UNSIGNED_HASH))
  73                 hash_alg += 3;
  74
  75         while (offset < fs->blocksize) {
  76                 dirent = (struct ext2_dir_entry *) (buf + offset);
  77                 errcode = ext2fs_get_rec_len(fs, dirent, &rec_len);
  78                 if (errcode) {
  79                         com_err("htree_dump_leaf_inode", errcode,
  80                                 "while getting rec_len for block %lu",
  81                                 (unsigned long) blk);
  82                         return;
  83                 }
  84                 thislen = ext2fs_dirent_name_len(dirent);
  85                 if (((offset + rec_len) > fs->blocksize) ||
  86                     (rec_len < 8) ||
  87                     ((rec_len % 4) != 0) ||
  88                     ((unsigned) thislen + 8 > rec_len)) {
  89                         fprintf(pager, "Corrupted directory block (%llu)!\n",
  90                                 (unsigned long long) blk);
  91                         break;
  92                 }
  93                 strncpy(name, dirent->name, thislen);
  94                 name[thislen] = '\0';
  95                 errcode = ext2fs_dirhash2(hash_alg, name, thislen,
  96                                           fs->encoding, hash_flags,
  97                                           fs->super->s_hash_seed,
  98                                           &hash, &minor_hash);
  99                 if (errcode)
 100                         com_err("htree_dump_leaf_node", errcode,
 101                                 "while calculating hash");
 102                 if ((offset == fs->blocksize - csum_size) &&
 103                     (dirent->inode == 0) &&
 104                     (dirent->rec_len == csum_size) &&
 105                     (dirent->name_len == EXT2_DIR_NAME_LEN_CSUM)) {
 106                         struct ext2_dir_entry_tail *t;
 107
 108                         t = (struct ext2_dir_entry_tail *) dirent;
 109
 110                         snprintf(tmp, EXT2_NAME_LEN + 64,
 111                                  "leaf block checksum: 0x%08x  ",
 112                                  t->det_checksum);
 113                 } else {
 114                         snprintf(tmp, EXT2_NAME_LEN + 64,
 115                                  "%u 0x%08x-%08x (%d) %s   ",
 116                                  dirent->inode, hash, minor_hash,
 117                                  rec_len, name);
 118                 }
 119                 thislen = strlen(tmp);
 120                 if (col + thislen > 80) {
 121                         fprintf(pager, "\n");
 122                         col = 0;
 123                 }
 124                 fprintf(pager, "%s", tmp);
 125                 col += thislen;
 126                 offset += rec_len;
 127         }
 128         fprintf(pager, "\n");
 129 }
 130
 131
 132 static void htree_dump_int_block(ext2_filsys fs, ext2_ino_t ino,
 133                                  struct ext2_inode *inode,
 134                                  struct ext2_dx_root_info * rootnode,
 135                                  blk64_t blk, char *buf, int level);
 136
 137
 138 static void htree_dump_int_node(ext2_filsys fs, ext2_ino_t ino,
 139                                 struct ext2_inode *inode,
 140                                 struct ext2_dx_root_info * rootnode,
 141                                 struct ext2_dx_entry *ent, __u32 crc,
 142                                 char *buf, int level)
 143 {
 144         struct ext2_dx_countlimit       dx_countlimit;
 145         struct ext2_dx_tail             *tail;
 146         int                             hash, i;
 147         int                             limit, count;
 148         int                             remainder;
 149
 150         dx_countlimit = *((struct ext2_dx_countlimit *) ent);
 151         count = ext2fs_le16_to_cpu(dx_countlimit.count);
 152         limit = ext2fs_le16_to_cpu(dx_countlimit.limit);
 153
 154         fprintf(pager, "Number of entries (count): %d\n", count);
 155         fprintf(pager, "Number of entries (limit): %d\n", limit);
 156
 157         remainder = fs->blocksize - (limit * sizeof(struct ext2_dx_entry));
 158         if (ent == (struct ext2_dx_entry *)(rootnode + 1))
 159                 remainder -= sizeof(struct ext2_dx_root_info) + 24;
 160         else
 161                 remainder -= 8;
 162         if (ext2fs_has_feature_metadata_csum(fs->super) &&
 163             remainder == sizeof(struct ext2_dx_tail)) {
 164                 tail = (struct ext2_dx_tail *)(ent + limit);
 165                 fprintf(pager, "Checksum: 0x%08x",
 166                         ext2fs_le32_to_cpu(tail->dt_checksum));
 167                 if (tail->dt_checksum != crc)
 168                         fprintf(pager, " --- EXPECTED: 0x%08x", crc);
 169                 fputc('\n', pager);
 170         }
 171
 172         for (i=0; i < count; i++) {
 173                 hash = i ? ext2fs_le32_to_cpu(ent[i].hash) : 0;
 174                 fprintf(pager, "Entry #%d: Hash 0x%08x%s, block %u\n", i,
 175                         hash, (hash & 1) ? " (**)" : "",
 176                         ext2fs_le32_to_cpu(ent[i].block));
 177                 }
 178
 179         fprintf(pager, "\n");
 180
 181         for (i=0; i < count; i++) {
 182                 unsigned int hashval, block;
 183
 184                 hashval = ext2fs_le32_to_cpu(ent[i].hash);
 185                 block = ext2fs_le32_to_cpu(ent[i].block);
 186                 fprintf(pager, "Entry #%d: Hash 0x%08x, block %u\n", i,
 187                        i ? hashval : 0, block);
 188                 if (level)
 189                         htree_dump_int_block(fs, ino, inode, rootnode,
 190                                              block, buf, level-1);
 191                 else
 192                         htree_dump_leaf_node(fs, ino, inode, rootnode,
 193                                              block, buf);
 194         }
 195
 196         fprintf(pager, "---------------------\n");
 197 }
 198
 199 static void htree_dump_int_block(ext2_filsys fs, ext2_ino_t ino,
 200                                  struct ext2_inode *inode,
 201                                  struct ext2_dx_root_info * rootnode,
 202                                  blk64_t blk, char *buf, int level)
 203 {
 204         char            *cbuf;
 205         errcode_t       errcode;
 206         blk64_t         pblk;
 207         __u32           crc;
 208
 209         cbuf = malloc(fs->blocksize);
 210         if (!cbuf) {
 211                 fprintf(pager, "Couldn't allocate child block.\n");
 212                 return;
 213         }
 214
 215         errcode = ext2fs_bmap2(fs, ino, inode, buf, 0, blk, 0, &pblk);
 216         if (errcode) {
 217                 com_err("htree_dump_int_block", errcode,
 218                         "while mapping logical block %llu\n",
 219                         (unsigned long long) blk);
 220                 goto errout;
 221         }
 222
 223         errcode = io_channel_read_blk64(current_fs->io, pblk, 1, buf);
 224         if (errcode) {
 225                 com_err("htree_dump_int_block", errcode,
 226                         "while reading block %llu\n",
 227                         (unsigned long long) blk);
 228                 goto errout;
 229         }
 230
 231         errcode = ext2fs_dx_csum(current_fs, ino,
 232                                  (struct ext2_dir_entry *) buf, &crc, NULL);
 233         if (errcode) {
 234                 com_err("htree_dump_int_block", errcode,
 235                         "while calculating checksum for logical block %llu\n",
 236                         (unsigned long long) blk);
 237                 crc = (unsigned int) -1;
 238         }
 239         htree_dump_int_node(fs, ino, inode, rootnode,
 240                             (struct ext2_dx_entry *) (buf+8),
 241                             crc, cbuf, level);
 242 errout:
 243         free(cbuf);
 244 }
 245
 246
 247
 248 void do_htree_dump(int argc, ss_argv_t argv, int sci_idx EXT2FS_ATTR((unused)),
 249                    void *infop EXT2FS_ATTR((unused)))
 250 {
 251         ext2_ino_t      ino;
 252         struct ext2_inode inode;
 253         blk64_t         blk;
 254         char            *buf = NULL;
 255         struct          ext2_dx_root_info  *rootnode;
 256         struct          ext2_dx_entry *ent;
 257         errcode_t       errcode;
 258         __u32           crc;
 259
 260         if (check_fs_open(argv[0]))
 261                 return;
 262
 263         pager = open_pager();
 264
 265         if (common_inode_args_process(argc, argv, &ino, 0))
 266                 goto errout;
 267
 268         if (debugfs_read_inode(ino, &inode, argv[1]))
 269                 goto errout;
 270
 271         if (!LINUX_S_ISDIR(inode.i_mode)) {
 272                 com_err(argv[0], 0, "Not a directory");
 273                 goto errout;
 274         }
 275
 276         if ((inode.i_flags & EXT2_BTREE_FL) == 0) {
 277                 com_err(argv[0], 0, "Not a hash-indexed directory");
 278                 goto errout;
 279         }
 280
 281         buf = malloc(2*current_fs->blocksize);
 282         if (!buf) {
 283                 com_err(argv[0], 0, "Couldn't allocate htree buffer");
 284                 goto errout;
 285         }
 286
 287         errcode = ext2fs_bmap2(current_fs, ino, &inode, buf, 0, 0, 0, &blk);
 288         if (errcode) {
 289                 com_err("do_htree_block", errcode,
 290                         "while mapping logical block 0\n");
 291                 goto errout;
 292         }
 293
 294         errcode = io_channel_read_blk64(current_fs->io, blk,
 295                                         1, buf);
 296         if (errcode) {
 297                 com_err(argv[0], errcode, "Error reading root node");
 298                 goto errout;
 299         }
 300
 301         rootnode = (struct ext2_dx_root_info *) (buf + 24);
 302
 303         fprintf(pager, "Root node dump:\n");
 304         fprintf(pager, "\t Reserved zero: %u\n", rootnode->reserved_zero);
 305         fprintf(pager, "\t Hash Version: %d\n", rootnode->hash_version);
 306         fprintf(pager, "\t Info length: %d\n", rootnode->info_length);
 307         fprintf(pager, "\t Indirect levels: %d\n", rootnode->indirect_levels);
 308         fprintf(pager, "\t Flags: %#x\n", rootnode->unused_flags);
 309
 310         ent = (struct ext2_dx_entry *)
 311                 ((char *)rootnode + rootnode->info_length);
 312
 313         errcode = ext2fs_dx_csum(current_fs, ino,
 314                                  (struct ext2_dir_entry *) buf, &crc, NULL);
 315         if (errcode) {
 316                 com_err("htree_dump_int_block", errcode,
 317                         "while calculating checksum for htree root\n");
 318                 crc = (unsigned int) -1;
 319         }
 320         htree_dump_int_node(current_fs, ino, &inode, rootnode, ent, crc,
 321                             buf + current_fs->blocksize,
 322                             rootnode->indirect_levels);
 323
 324 errout:
 325         free(buf);
 326         close_pager(pager);
 327 }
 328
 329 /*
 330  * This function prints the hash of a given file.
 331  */
 332 void do_dx_hash(int argc, ss_argv_t argv, int sci_idx EXT2FS_ATTR((unused)),
 333                 void *infop EXT2FS_ATTR((unused)))
 334 {
 335         ext2_dirhash_t hash, minor_hash;
 336         errcode_t       err;
 337         int             c, verbose = 0;
 338         int             hash_version = 0;
 339         __u32           hash_seed[4] = { 0, };
 340         int             hash_flags = 0;
 341         const struct ext2fs_nls_table *encoding = NULL;
 342
 343         if (current_fs) {
 344                 hash_seed[0] = current_fs->super->s_hash_seed[0];
 345                 hash_seed[1] = current_fs->super->s_hash_seed[1];
 346                 hash_seed[2] = current_fs->super->s_hash_seed[2];
 347                 hash_seed[3] = current_fs->super->s_hash_seed[3];
 348
 349                 hash_version = current_fs->super->s_def_hash_version;
 350                 if (hash_version <= EXT2_HASH_TEA &&
 351                     current_fs->super->s_flags & EXT2_FLAGS_UNSIGNED_HASH)
 352                         hash_version += 3;
 353         }
 354
 355         reset_getopt();
 356         while ((c = getopt(argc, argv, "h:s:ce:v")) != EOF) {
 357                 switch (c) {
 358                 case 'h':
 359                         hash_version = e2p_string2hash(optarg);
 360                         if (hash_version < 0)
 361                                 hash_version = atoi(optarg);
 362                         break;
 363                 case 's':
 364                         if (uuid_parse(optarg, (unsigned char *) hash_seed)) {
 365                                 fprintf(stderr, "Invalid UUID format: %s\n",
 366                                         optarg);
 367                                 return;
 368                         }
 369                         break;
 370                 case 'c':
 371                         hash_flags |= EXT4_CASEFOLD_FL;
 372                         break;
 373                 case 'e':
 374                         encoding = ext2fs_load_nls_table(e2p_str2encoding(optarg));
 375                         if (!encoding) {
 376                                 fprintf(stderr, "Invalid encoding: %s\n",
 377                                         optarg);
 378                                 return;
 379                         }
 380                         break;
 381                 case 'v':
 382                         verbose = 1;
 383                         break;
 384                 default:
 385                         goto print_usage;
 386                 }
 387         }
 388         if (optind != argc-1) {
 389         print_usage:
 390                 com_err(argv[0], 0, "usage: dx_hash [-cv] [-h hash_alg] "
 391                         "[-s hash_seed] [-e encoding] filename");
 392                 return;
 393         }
 394         err = ext2fs_dirhash2(hash_version, argv[optind],
 395                               strlen(argv[optind]), encoding, hash_flags,
 396                               hash_seed, &hash, &minor_hash);
 397
 398         if (err) {
 399                 com_err(argv[0], err, "while calculating hash");
 400                 return;
 401         }
 402         printf("Hash of %s is 0x%0x (minor 0x%0x)\n", argv[optind],
 403                hash, minor_hash);
 404         if (verbose) {
 405                 char uuid_str[37];
 406
 407                 uuid_unparse((__u8 *) hash_seed, uuid_str);
 408                 printf("  using hash algorithm %d and hash_seed %s\n",
 409                        hash_version, uuid_str);
 410         }
 411 }
 412
 413 /*
 414  * Search for particular directory entry (useful for debugging very
 415  * large hash tree directories that have lost some blocks from the
 416  * btree index).
 417  */
 418 struct process_block_struct {
 419         char    *search_name;
 420         char    *buf;
 421         int     len;
 422 };
 423
 424 static int search_dir_block(ext2_filsys fs, blk64_t *blocknr,
 425                             e2_blkcnt_t blockcnt, blk64_t ref_blk,
 426                             int ref_offset, void *priv_data);
 427
 428 void do_dirsearch(int argc, ss_argv_t argv, int sci_idx EXT2FS_ATTR((unused)),
 429                   void *infop EXT2FS_ATTR((unused)))
 430 {
 431         ext2_ino_t      inode;
 432         struct process_block_struct pb;
 433
 434         if (check_fs_open(argv[0]))
 435                 return;
 436
 437         if (argc != 3) {
 438                 com_err(0, 0, "Usage: dirsearch dir filename");
 439                 return;
 440         }
 441
 442         inode = string_to_inode(argv[1]);
 443         if (!inode)
 444                 return;
 445
 446         pb.buf = malloc(current_fs->blocksize);
 447         if (!pb.buf) {
 448                 com_err("dirsearch", 0, "Couldn't allocate buffer");
 449                 return;
 450         }
 451         pb.search_name = argv[2];
 452         pb.len = strlen(pb.search_name);
 453
 454         ext2fs_block_iterate3(current_fs, inode, BLOCK_FLAG_READ_ONLY, 0,
 455                               search_dir_block, &pb);
 456
 457         free(pb.buf);
 458 }
 459
 460
 461 static int search_dir_block(ext2_filsys fs, blk64_t *blocknr,
 462                             e2_blkcnt_t blockcnt,
 463                             blk64_t ref_blk EXT2FS_ATTR((unused)),
 464                             int ref_offset EXT2FS_ATTR((unused)),
 465                             void *priv_data)
 466 {
 467         struct process_block_struct *p;
 468         struct ext2_dir_entry *dirent;
 469         errcode_t               errcode;
 470         unsigned int            offset = 0;
 471         unsigned int            rec_len;
 472
 473         if (blockcnt < 0)
 474                 return 0;
 475
 476         p = (struct process_block_struct *) priv_data;
 477
 478         errcode = io_channel_read_blk64(current_fs->io, *blocknr, 1, p->buf);
 479         if (errcode) {
 480                 com_err("search_dir_block", errcode,
 481                         "while reading block %lu", (unsigned long) *blocknr);
 482                 return BLOCK_ABORT;
 483         }
 484
 485         while (offset < fs->blocksize) {
 486                 dirent = (struct ext2_dir_entry *) (p->buf + offset);
 487                 errcode = ext2fs_get_rec_len(fs, dirent, &rec_len);
 488                 if (errcode) {
 489                         com_err("htree_dump_leaf_inode", errcode,
 490                                 "while getting rec_len for block %lu",
 491                                 (unsigned long) *blocknr);
 492                         return BLOCK_ABORT;
 493                 }
 494                 if (dirent->inode &&
 495                     p->len == ext2fs_dirent_name_len(dirent) &&
 496                     strncmp(p->search_name, dirent->name,
 497                             p->len) == 0) {
 498                         printf("Entry found at logical block %lld, "
 499                                "phys %llu, offset %u\n", (long long)blockcnt,
 500                                (unsigned long long) *blocknr, offset);
 501                         printf("offset %u\n", offset);
 502                         return BLOCK_ABORT;
 503                 }
 504                 offset += rec_len;
 505         }
 506         return 0;
 507 }
 508