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