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 <stdio.h>
   9 #include <unistd.h>
  10 #include <stdlib.h>
  11 #include <ctype.h>
  12 #include <string.h>
  13 #include <time.h>
  14 #ifdef HAVE_ERRNO_H
  15 #include <errno.h>
  16 #endif
  17 #include <sys/types.h>
  18 #ifdef HAVE_GETOPT_H
  19 #include <getopt.h>
  20 #else
  21 extern int optind;
  22 extern char *optarg;
  23 #endif
  24
  25 #include "debugfs.h"
  26
  27 static FILE *pager;
  28
  29 static void htree_dump_leaf_node(ext2_filsys fs, ext2_ino_t ino,
  30                                  struct ext2_inode *inode,
  31                                  struct ext2_dx_root_info * rootnode,
  32                                  blk_t blk, char *buf)
  33 {
  34         errcode_t       errcode;
  35         struct ext2_dir_entry *dirent;
  36         int             thislen, col = 0;
  37         unsigned int    offset = 0;
  38         char            name[EXT2_NAME_LEN + 1];
  39         char            tmp[EXT2_NAME_LEN + 16];
  40         blk_t           pblk;
  41         ext2_dirhash_t  hash, minor_hash;
  42         int             rec_len, hash_alg;
  43
  44         errcode = ext2fs_bmap(fs, ino, inode, buf, 0, blk, &pblk);
  45         if (errcode) {
  46                 com_err("htree_dump_leaf_node", errcode,
  47                         "while mapping logical block %u\n", blk);
  48                 return;
  49         }
  50
  51         printf("Reading directory block %lu, phys %lu\n", blk, pblk);
  52         errcode = ext2fs_read_dir_block2(current_fs, pblk, buf, 0);
  53         if (errcode) {
  54                 com_err("htree_dump_leaf_node", errcode,
  55                         "while reading block %lu (%lu)\n", blk, pblk);
  56                 return;
  57         }
  58         hash_alg = rootnode->hash_version;
  59         if ((hash_alg <= EXT2_HASH_TEA) &&
  60             (fs->super->s_flags & EXT2_FLAGS_UNSIGNED_HASH))
  61                 hash_alg += 3;
  62
  63         while (offset < fs->blocksize) {
  64                 dirent = (struct ext2_dir_entry *) (buf + offset);
  65                 rec_len = (dirent->rec_len || fs->blocksize < 65536) ?
  66                         dirent->rec_len : 65536;
  67                 if (((offset + rec_len) > fs->blocksize) ||
  68                     (rec_len < 8) ||
  69                     ((rec_len % 4) != 0) ||
  70                     (((dirent->name_len & 0xFF)+8) > rec_len)) {
  71                         fprintf(pager, "Corrupted directory block (%u)!\n", blk);
  72                         break;
  73                 }
  74                 thislen = ((dirent->name_len & 0xFF) < EXT2_NAME_LEN) ?
  75                         (dirent->name_len & 0xFF) : EXT2_NAME_LEN;
  76                 strncpy(name, dirent->name, thislen);
  77                 name[thislen] = '\0';
  78                 errcode = ext2fs_dirhash(hash_alg, name,
  79                                          thislen, fs->super->s_hash_seed,
  80                                          &hash, &minor_hash);
  81                 if (errcode)
  82                         com_err("htree_dump_leaf_node", errcode,
  83                                 "while calculating hash");
  84                 sprintf(tmp, "%u 0x%08x-%08x (%d) %s   ", dirent->inode,
  85                         hash, minor_hash, rec_len, name);
  86                 thislen = strlen(tmp);
  87                 if (col + thislen > 80) {
  88                         fprintf(pager, "\n");
  89                         col = 0;
  90                 }
  91                 fprintf(pager, "%s", tmp);
  92                 col += thislen;
  93                 offset += rec_len;
  94         }
  95         fprintf(pager, "\n");
  96 }
  97
  98
  99 static void htree_dump_int_block(ext2_filsys fs, ext2_ino_t ino,
 100                                  struct ext2_inode *inode,
 101                                  struct ext2_dx_root_info * rootnode,
 102                                  blk_t blk, char *buf, int level);
 103
 104
 105 static void htree_dump_int_node(ext2_filsys fs, ext2_ino_t ino,
 106                                 struct ext2_inode *inode,
 107                                 struct ext2_dx_root_info * rootnode,
 108                                 struct ext2_dx_entry *ent,
 109                                 char *buf, int level)
 110 {
 111         struct ext2_dx_countlimit       limit;
 112         struct ext2_dx_entry            e;
 113         int                             hash, i;
 114
 115
 116         limit = *((struct ext2_dx_countlimit *) ent);
 117         limit.count = ext2fs_le16_to_cpu(limit.count);
 118         limit.limit = ext2fs_le16_to_cpu(limit.limit);
 119
 120         fprintf(pager, "Number of entries (count): %d\n", limit.count);
 121         fprintf(pager, "Number of entries (limit): %d\n", limit.limit);
 122
 123         for (i=0; i < limit.count; i++) {
 124                 hash = i ? ext2fs_le32_to_cpu(ent[i].hash) : 0;
 125                 fprintf(pager, "Entry #%d: Hash 0x%08x%s, block %u\n", i,
 126                         hash, (hash & 1) ? " (**)" : "",
 127                         ext2fs_le32_to_cpu(ent[i].block));
 128                 }
 129
 130         fprintf(pager, "\n");
 131
 132         for (i=0; i < limit.count; i++) {
 133                 e.hash = ext2fs_le32_to_cpu(ent[i].hash);
 134                 e.block = ext2fs_le32_to_cpu(ent[i].block);
 135                 fprintf(pager, "Entry #%d: Hash 0x%08x, block %u\n", i,
 136                        i ? e.hash : 0, e.block);
 137                 if (level)
 138                         htree_dump_int_block(fs, ino, inode, rootnode,
 139                                              e.block, buf, level-1);
 140                 else
 141                         htree_dump_leaf_node(fs, ino, inode, rootnode,
 142                                              e.block, buf);
 143         }
 144
 145         fprintf(pager, "---------------------\n");
 146 }
 147
 148 static void htree_dump_int_block(ext2_filsys fs, ext2_ino_t ino,
 149                                  struct ext2_inode *inode,
 150                                  struct ext2_dx_root_info * rootnode,
 151                                  blk_t blk, char *buf, int level)
 152 {
 153         char            *cbuf;
 154         errcode_t       errcode;
 155         blk_t           pblk;
 156
 157         cbuf = malloc(fs->blocksize);
 158         if (!cbuf) {
 159                 fprintf(pager, "Couldn't allocate child block.\n");
 160                 return;
 161         }
 162
 163         errcode = ext2fs_bmap(fs, ino, inode, buf, 0, blk, &pblk);
 164         if (errcode) {
 165                 com_err("htree_dump_int_block", errcode,
 166                         "while mapping logical block %u\n", blk);
 167                 goto errout;
 168         }
 169
 170         errcode = io_channel_read_blk(current_fs->io, pblk, 1, buf);
 171         if (errcode) {
 172                 com_err("htree_dump_int_block", errcode,
 173                         "while  reading block %u\n", blk);
 174                 goto errout;
 175         }
 176
 177         htree_dump_int_node(fs, ino, inode, rootnode,
 178                             (struct ext2_dx_entry *) (buf+8),
 179                             cbuf, level);
 180 errout:
 181         free(cbuf);
 182 }
 183
 184
 185
 186 void do_htree_dump(int argc, char *argv[])
 187 {
 188         ext2_ino_t      ino;
 189         struct ext2_inode inode;
 190         int             c;
 191         int             long_opt = 0;
 192         blk_t           blk;
 193         char            *buf = NULL;
 194         struct          ext2_dx_root_info  *rootnode;
 195         struct          ext2_dx_entry *ent;
 196         struct          ext2_dx_countlimit *limit;
 197         errcode_t       errcode;
 198
 199         if (check_fs_open(argv[0]))
 200                 return;
 201
 202         pager = open_pager();
 203
 204         reset_getopt();
 205         while ((c = getopt (argc, argv, "l")) != EOF) {
 206                 switch (c) {
 207                 case 'l':
 208                         long_opt++;
 209                         break;
 210                 default:
 211                         goto print_usage;
 212                 }
 213         }
 214
 215         if (argc > optind+1) {
 216         print_usage:
 217                 com_err(0, 0, "Usage: htree_dump [-l] file");
 218                 goto errout;
 219         }
 220
 221         if (argc == optind)
 222                 ino = cwd;
 223         else
 224                 ino = string_to_inode(argv[optind]);
 225         if (!ino)
 226                 goto errout;
 227
 228         if (debugfs_read_inode(ino, &inode, argv[1]))
 229                 goto errout;
 230
 231         if (!LINUX_S_ISDIR(inode.i_mode)) {
 232                 com_err(argv[0], 0, "Not a directory");
 233                 goto errout;
 234         }
 235
 236         if ((inode.i_flags & EXT2_BTREE_FL) == 0) {
 237                 com_err(argv[0], 0, "Not a hash-indexed directory");
 238                 goto errout;
 239         }
 240
 241         buf = malloc(2*current_fs->blocksize);
 242         if (!buf) {
 243                 com_err(argv[0], 0, "Couldn't allocate htree buffer");
 244                 goto errout;
 245         }
 246
 247         errcode = ext2fs_bmap(current_fs, ino, &inode, buf, 0, 0, &blk);
 248         if (errcode) {
 249                 com_err("do_htree_block", errcode,
 250                         "while mapping logical block 0\n");
 251                 goto errout;
 252         }
 253
 254         errcode = io_channel_read_blk(current_fs->io, blk,
 255                                       1, buf);
 256         if (errcode) {
 257                 com_err(argv[0], errcode, "Error reading root node");
 258                 goto errout;
 259         }
 260
 261         rootnode = (struct ext2_dx_root_info *) (buf + 24);
 262
 263         fprintf(pager, "Root node dump:\n");
 264         fprintf(pager, "\t Reserved zero: %u\n", rootnode->reserved_zero);
 265         fprintf(pager, "\t Hash Version: %d\n", rootnode->hash_version);
 266         fprintf(pager, "\t Info length: %d\n", rootnode->info_length);
 267         fprintf(pager, "\t Indirect levels: %d\n", rootnode->indirect_levels);
 268         fprintf(pager, "\t Flags: %d\n", rootnode->unused_flags);
 269
 270         ent = (struct ext2_dx_entry *) (buf + 24 + rootnode->info_length);
 271         limit = (struct ext2_dx_countlimit *) ent;
 272
 273         htree_dump_int_node(current_fs, ino, &inode, rootnode, ent,
 274                             buf + current_fs->blocksize,
 275                             rootnode->indirect_levels);
 276
 277 errout:
 278         free(buf);
 279         close_pager(pager);
 280 }
 281
 282 /*
 283  * This function prints the hash of a given file.
 284  */
 285 void do_dx_hash(int argc, char *argv[])
 286 {
 287         ext2_dirhash_t hash, minor_hash;
 288         errcode_t       err;
 289         int             c;
 290         int             hash_version = 0;
 291         __u32           hash_seed[4];
 292
 293         hash_seed[0] = hash_seed[1] = hash_seed[2] = hash_seed[3] = 0;
 294
 295         reset_getopt();
 296         while ((c = getopt (argc, argv, "h:s:")) != EOF) {
 297                 switch (c) {
 298                 case 'h':
 299                         hash_version = e2p_string2hash(optarg);
 300                         if (hash_version < 0)
 301                                 hash_version = atoi(optarg);
 302                         break;
 303                 case 's':
 304                         if (uuid_parse(optarg, hash_seed)) {
 305                                 fprintf(stderr, "Invalid UUID format: %s\n",
 306                                         optarg);
 307                                 return;
 308                         }
 309                         break;
 310                 default:
 311                         goto print_usage;
 312                 }
 313         }
 314         if (optind != argc-1) {
 315         print_usage:
 316                 com_err(argv[0], 0, "usage: dx_hash [-h hash_alg] "
 317                         "[-s hash_seed] filename");
 318                 return;
 319         }
 320         err = ext2fs_dirhash(hash_version, argv[optind], strlen(argv[optind]),
 321                              hash_seed, &hash, &minor_hash);
 322         if (err) {
 323                 com_err(argv[0], err, "while caclulating hash");
 324                 return;
 325         }
 326         printf("Hash of %s is 0x%0x (minor 0x%0x)\n", argv[optind],
 327                hash, minor_hash);
 328 }
 329
 330 /*
 331  * Search for particular directory entry (useful for debugging very
 332  * large hash tree directories that have lost some blocks from the
 333  * btree index).
 334  */
 335 struct process_block_struct {
 336         char    *search_name;
 337         char    *buf;
 338         int     len;
 339 };
 340
 341 static int search_dir_block(ext2_filsys fs, blk_t *blocknr,
 342                             e2_blkcnt_t blockcnt, blk_t ref_blk,
 343                             int ref_offset, void *priv_data);
 344
 345 void do_dirsearch(int argc, char *argv[])
 346 {
 347         ext2_ino_t      inode;
 348         struct process_block_struct pb;
 349
 350         if (check_fs_open(argv[0]))
 351                 return;
 352
 353         if (argc != 3) {
 354                 com_err(0, 0, "Usage: dirsearch dir filename");
 355                 return;
 356         }
 357
 358         inode = string_to_inode(argv[1]);
 359         if (!inode)
 360                 return;
 361
 362         pb.buf = malloc(current_fs->blocksize);
 363         if (!pb.buf) {
 364                 com_err("dirsearch", 0, "Couldn't allocate buffer");
 365                 return;
 366         }
 367         pb.search_name = argv[2];
 368         pb.len = strlen(pb.search_name);
 369
 370         ext2fs_block_iterate2(current_fs, inode, BLOCK_FLAG_READ_ONLY, 0,
 371                               search_dir_block, &pb);
 372
 373         free(pb.buf);
 374 }
 375
 376
 377 static int search_dir_block(ext2_filsys fs, blk_t *blocknr,
 378                             e2_blkcnt_t blockcnt,
 379                             blk_t ref_blk EXT2FS_ATTR((unused)),
 380                             int ref_offset EXT2FS_ATTR((unused)),
 381                             void *priv_data)
 382 {
 383         struct process_block_struct *p;
 384         struct ext2_dir_entry *dirent;
 385         errcode_t               errcode;
 386         unsigned int            offset = 0;
 387         int                     rec_len;
 388
 389         if (blockcnt < 0)
 390                 return 0;
 391
 392         p = (struct process_block_struct *) priv_data;
 393
 394         errcode = io_channel_read_blk(current_fs->io, *blocknr, 1, p->buf);
 395         if (errcode) {
 396                 com_err("search_dir_block", errcode,
 397                         "while reading block %lu", (unsigned long) *blocknr);
 398                 return BLOCK_ABORT;
 399         }
 400
 401         while (offset < fs->blocksize) {
 402                 dirent = (struct ext2_dir_entry *) (p->buf + offset);
 403                 rec_len = (dirent->rec_len || fs->blocksize < 65536) ?
 404                         dirent->rec_len : 65536;
 405                 if (dirent->inode &&
 406                     p->len == (dirent->name_len & 0xFF) &&
 407                     strncmp(p->search_name, dirent->name,
 408                             p->len) == 0) {
 409                         printf("Entry found at logical block %lld, "
 410                                "phys %u, offset %u\n", (long long)blockcnt,
 411                                *blocknr, offset);
 412                         printf("offset %u\n", offset);
 413                         return BLOCK_ABORT;
 414                 }
 415                 offset += rec_len;
 416         }
 417         return 0;
 418 }
 419