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             csum_size = 0;
  48
  49         if (EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
  50                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
  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_dirhash(hash_alg, name,
  94                                          thislen, fs->super->s_hash_seed,
  95                                          &hash, &minor_hash);
  96                 if (errcode)
  97                         com_err("htree_dump_leaf_node", errcode,
  98                                 "while calculating hash");
  99                 if ((offset == fs->blocksize - csum_size) &&
 100                     (dirent->inode == 0) &&
 101                     (dirent->rec_len == csum_size) &&
 102                     (dirent->name_len == EXT2_DIR_NAME_LEN_CSUM)) {
 103                         struct ext2_dir_entry_tail *t;
 104
 105                         t = (struct ext2_dir_entry_tail *) dirent;
 106
 107                         snprintf(tmp, EXT2_NAME_LEN + 64,
 108                                  "leaf block checksum: 0x%08x  ",
 109                                  t->det_checksum);
 110                 } else {
 111                         snprintf(tmp, EXT2_NAME_LEN + 64,
 112                                  "%u 0x%08x-%08x (%d) %s   ",
 113                                  dirent->inode, hash, minor_hash,
 114                                  rec_len, name);
 115                 }
 116                 thislen = strlen(tmp);
 117                 if (col + thislen > 80) {
 118                         fprintf(pager, "\n");
 119                         col = 0;
 120                 }
 121                 fprintf(pager, "%s", tmp);
 122                 col += thislen;
 123                 offset += rec_len;
 124         }
 125         fprintf(pager, "\n");
 126 }
 127
 128
 129 static void htree_dump_int_block(ext2_filsys fs, ext2_ino_t ino,
 130                                  struct ext2_inode *inode,
 131                                  struct ext2_dx_root_info * rootnode,
 132                                  blk64_t blk, char *buf, int level);
 133
 134
 135 static void htree_dump_int_node(ext2_filsys fs, ext2_ino_t ino,
 136                                 struct ext2_inode *inode,
 137                                 struct ext2_dx_root_info * rootnode,
 138                                 struct ext2_dx_entry *ent,
 139                                 char *buf, int level)
 140 {
 141         struct ext2_dx_countlimit       dx_countlimit;
 142         struct ext2_dx_tail             *tail;
 143         int                             hash, i;
 144         int                             limit, count;
 145         int                             remainder;
 146
 147         dx_countlimit = *((struct ext2_dx_countlimit *) ent);
 148         count = ext2fs_le16_to_cpu(dx_countlimit.count);
 149         limit = ext2fs_le16_to_cpu(dx_countlimit.limit);
 150
 151         fprintf(pager, "Number of entries (count): %d\n", count);
 152         fprintf(pager, "Number of entries (limit): %d\n", limit);
 153
 154         remainder = fs->blocksize - (limit * sizeof(struct ext2_dx_entry));
 155         if (ent == (struct ext2_dx_entry *)(rootnode + 1))
 156                 remainder -= sizeof(struct ext2_dx_root_info) + 24;
 157         else
 158                 remainder -= 8;
 159         if (EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
 160                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
 161             remainder == sizeof(struct ext2_dx_tail)) {
 162                 tail = (struct ext2_dx_tail *)(ent + limit);
 163                 fprintf(pager, "Checksum: 0x%08x\n",
 164                         ext2fs_le32_to_cpu(tail->dt_checksum));
 165         }
 166
 167         for (i=0; i < count; i++) {
 168                 hash = i ? ext2fs_le32_to_cpu(ent[i].hash) : 0;
 169                 fprintf(pager, "Entry #%d: Hash 0x%08x%s, block %u\n", i,
 170                         hash, (hash & 1) ? " (**)" : "",
 171                         ext2fs_le32_to_cpu(ent[i].block));
 172                 }
 173
 174         fprintf(pager, "\n");
 175
 176         for (i=0; i < count; i++) {
 177                 unsigned int hashval, block;
 178
 179                 hashval = ext2fs_le32_to_cpu(ent[i].hash);
 180                 block = ext2fs_le32_to_cpu(ent[i].block);
 181                 fprintf(pager, "Entry #%d: Hash 0x%08x, block %u\n", i,
 182                        i ? hashval : 0, block);
 183                 if (level)
 184                         htree_dump_int_block(fs, ino, inode, rootnode,
 185                                              block, buf, level-1);
 186                 else
 187                         htree_dump_leaf_node(fs, ino, inode, rootnode,
 188                                              block, buf);
 189         }
 190
 191         fprintf(pager, "---------------------\n");
 192 }
 193
 194 static void htree_dump_int_block(ext2_filsys fs, ext2_ino_t ino,
 195                                  struct ext2_inode *inode,
 196                                  struct ext2_dx_root_info * rootnode,
 197                                  blk64_t blk, char *buf, int level)
 198 {
 199         char            *cbuf;
 200         errcode_t       errcode;
 201         blk64_t         pblk;
 202
 203         cbuf = malloc(fs->blocksize);
 204         if (!cbuf) {
 205                 fprintf(pager, "Couldn't allocate child block.\n");
 206                 return;
 207         }
 208
 209         errcode = ext2fs_bmap2(fs, ino, inode, buf, 0, blk, 0, &pblk);
 210         if (errcode) {
 211                 com_err("htree_dump_int_block", errcode,
 212                         "while mapping logical block %llu\n", blk);
 213                 goto errout;
 214         }
 215
 216         errcode = io_channel_read_blk64(current_fs->io, pblk, 1, buf);
 217         if (errcode) {
 218                 com_err("htree_dump_int_block", errcode,
 219                         "while  reading block %llu\n", blk);
 220                 goto errout;
 221         }
 222
 223         htree_dump_int_node(fs, ino, inode, rootnode,
 224                             (struct ext2_dx_entry *) (buf+8),
 225                             cbuf, level);
 226 errout:
 227         free(cbuf);
 228 }
 229
 230
 231
 232 void do_htree_dump(int argc, char *argv[])
 233 {
 234         ext2_ino_t      ino;
 235         struct ext2_inode inode;
 236         blk64_t         blk;
 237         char            *buf = NULL;
 238         struct          ext2_dx_root_info  *rootnode;
 239         struct          ext2_dx_entry *ent;
 240         errcode_t       errcode;
 241
 242         if (check_fs_open(argv[0]))
 243                 return;
 244
 245         pager = open_pager();
 246
 247         if (common_inode_args_process(argc, argv, &ino, 0))
 248                 goto errout;
 249
 250         if (debugfs_read_inode(ino, &inode, argv[1]))
 251                 goto errout;
 252
 253         if (!LINUX_S_ISDIR(inode.i_mode)) {
 254                 com_err(argv[0], 0, "Not a directory");
 255                 goto errout;
 256         }
 257
 258         if ((inode.i_flags & EXT2_BTREE_FL) == 0) {
 259                 com_err(argv[0], 0, "Not a hash-indexed directory");
 260                 goto errout;
 261         }
 262
 263         buf = malloc(2*current_fs->blocksize);
 264         if (!buf) {
 265                 com_err(argv[0], 0, "Couldn't allocate htree buffer");
 266                 goto errout;
 267         }
 268
 269         errcode = ext2fs_bmap2(current_fs, ino, &inode, buf, 0, 0, 0, &blk);
 270         if (errcode) {
 271                 com_err("do_htree_block", errcode,
 272                         "while mapping logical block 0\n");
 273                 goto errout;
 274         }
 275
 276         errcode = io_channel_read_blk64(current_fs->io, blk,
 277                                         1, buf);
 278         if (errcode) {
 279                 com_err(argv[0], errcode, "Error reading root node");
 280                 goto errout;
 281         }
 282
 283         rootnode = (struct ext2_dx_root_info *) (buf + 24);
 284
 285         fprintf(pager, "Root node dump:\n");
 286         fprintf(pager, "\t Reserved zero: %u\n", rootnode->reserved_zero);
 287         fprintf(pager, "\t Hash Version: %d\n", rootnode->hash_version);
 288         fprintf(pager, "\t Info length: %d\n", rootnode->info_length);
 289         fprintf(pager, "\t Indirect levels: %d\n", rootnode->indirect_levels);
 290         fprintf(pager, "\t Flags: %d\n", rootnode->unused_flags);
 291
 292         ent = (struct ext2_dx_entry *) (buf + 24 + rootnode->info_length);
 293
 294         htree_dump_int_node(current_fs, ino, &inode, rootnode, ent,
 295                             buf + current_fs->blocksize,
 296                             rootnode->indirect_levels);
 297
 298 errout:
 299         free(buf);
 300         close_pager(pager);
 301 }
 302
 303 /*
 304  * This function prints the hash of a given file.
 305  */
 306 void do_dx_hash(int argc, char *argv[])
 307 {
 308         ext2_dirhash_t hash, minor_hash;
 309         errcode_t       err;
 310         int             c;
 311         int             hash_version = 0;
 312         __u32           hash_seed[4];
 313
 314         hash_seed[0] = hash_seed[1] = hash_seed[2] = hash_seed[3] = 0;
 315
 316         reset_getopt();
 317         while ((c = getopt (argc, argv, "h:s:")) != EOF) {
 318                 switch (c) {
 319                 case 'h':
 320                         hash_version = e2p_string2hash(optarg);
 321                         if (hash_version < 0)
 322                                 hash_version = atoi(optarg);
 323                         break;
 324                 case 's':
 325                         if (uuid_parse(optarg, (unsigned char *) hash_seed)) {
 326                                 fprintf(stderr, "Invalid UUID format: %s\n",
 327                                         optarg);
 328                                 return;
 329                         }
 330                         break;
 331                 default:
 332                         goto print_usage;
 333                 }
 334         }
 335         if (optind != argc-1) {
 336         print_usage:
 337                 com_err(argv[0], 0, "usage: dx_hash [-h hash_alg] "
 338                         "[-s hash_seed] filename");
 339                 return;
 340         }
 341         err = ext2fs_dirhash(hash_version, argv[optind], strlen(argv[optind]),
 342                              hash_seed, &hash, &minor_hash);
 343         if (err) {
 344                 com_err(argv[0], err, "while caclulating hash");
 345                 return;
 346         }
 347         printf("Hash of %s is 0x%0x (minor 0x%0x)\n", argv[optind],
 348                hash, minor_hash);
 349 }
 350
 351 /*
 352  * Search for particular directory entry (useful for debugging very
 353  * large hash tree directories that have lost some blocks from the
 354  * btree index).
 355  */
 356 struct process_block_struct {
 357         char    *search_name;
 358         char    *buf;
 359         int     len;
 360 };
 361
 362 static int search_dir_block(ext2_filsys fs, blk64_t *blocknr,
 363                             e2_blkcnt_t blockcnt, blk64_t ref_blk,
 364                             int ref_offset, void *priv_data);
 365
 366 void do_dirsearch(int argc, char *argv[])
 367 {
 368         ext2_ino_t      inode;
 369         struct process_block_struct pb;
 370
 371         if (check_fs_open(argv[0]))
 372                 return;
 373
 374         if (argc != 3) {
 375                 com_err(0, 0, "Usage: dirsearch dir filename");
 376                 return;
 377         }
 378
 379         inode = string_to_inode(argv[1]);
 380         if (!inode)
 381                 return;
 382
 383         pb.buf = malloc(current_fs->blocksize);
 384         if (!pb.buf) {
 385                 com_err("dirsearch", 0, "Couldn't allocate buffer");
 386                 return;
 387         }
 388         pb.search_name = argv[2];
 389         pb.len = strlen(pb.search_name);
 390
 391         ext2fs_block_iterate3(current_fs, inode, BLOCK_FLAG_READ_ONLY, 0,
 392                               search_dir_block, &pb);
 393
 394         free(pb.buf);
 395 }
 396
 397
 398 static int search_dir_block(ext2_filsys fs, blk64_t *blocknr,
 399                             e2_blkcnt_t blockcnt,
 400                             blk64_t ref_blk EXT2FS_ATTR((unused)),
 401                             int ref_offset EXT2FS_ATTR((unused)),
 402                             void *priv_data)
 403 {
 404         struct process_block_struct *p;
 405         struct ext2_dir_entry *dirent;
 406         errcode_t               errcode;
 407         unsigned int            offset = 0;
 408         unsigned int            rec_len;
 409
 410         if (blockcnt < 0)
 411                 return 0;
 412
 413         p = (struct process_block_struct *) priv_data;
 414
 415         errcode = io_channel_read_blk64(current_fs->io, *blocknr, 1, p->buf);
 416         if (errcode) {
 417                 com_err("search_dir_block", errcode,
 418                         "while reading block %lu", (unsigned long) *blocknr);
 419                 return BLOCK_ABORT;
 420         }
 421
 422         while (offset < fs->blocksize) {
 423                 dirent = (struct ext2_dir_entry *) (p->buf + offset);
 424                 errcode = ext2fs_get_rec_len(fs, dirent, &rec_len);
 425                 if (errcode) {
 426                         com_err("htree_dump_leaf_inode", errcode,
 427                                 "while getting rec_len for block %lu",
 428                                 (unsigned long) *blocknr);
 429                         return BLOCK_ABORT;
 430                 }
 431                 if (dirent->inode &&
 432                     p->len == ext2fs_dirent_name_len(dirent) &&
 433                     strncmp(p->search_name, dirent->name,
 434                             p->len) == 0) {
 435                         printf("Entry found at logical block %lld, "
 436                                "phys %llu, offset %u\n", (long long)blockcnt,
 437                                *blocknr, offset);
 438                         printf("offset %u\n", offset);
 439                         return BLOCK_ABORT;
 440                 }
 441                 offset += rec_len;
 442         }
 443         return 0;
 444 }
 445