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 (ext2fs_has_feature_metadata_csum(fs->super))
  50                 csum_size = sizeof(struct ext2_dir_entry_tail);
  51
  52         errcode = ext2fs_bmap2(fs, ino, inode, buf, 0, blk, 0, &pblk);
  53         if (errcode) {
  54                 com_err("htree_dump_leaf_node", errcode,
  55                         "while mapping logical block %llu\n", blk);
  56                 return;
  57         }
  58
  59         fprintf(pager, "Reading directory block %llu, phys %llu\n", blk, pblk);
  60         errcode = ext2fs_read_dir_block4(current_fs, pblk, buf, 0, ino);
  61         if (errcode) {
  62                 com_err("htree_dump_leaf_node", errcode,
  63                         "while reading block %llu (%llu)\n",
  64                         blk, pblk);
  65                 return;
  66         }
  67         hash_alg = rootnode->hash_version;
  68         if ((hash_alg <= EXT2_HASH_TEA) &&
  69             (fs->super->s_flags & EXT2_FLAGS_UNSIGNED_HASH))
  70                 hash_alg += 3;
  71
  72         while (offset < fs->blocksize) {
  73                 dirent = (struct ext2_dir_entry *) (buf + offset);
  74                 errcode = ext2fs_get_rec_len(fs, dirent, &rec_len);
  75                 if (errcode) {
  76                         com_err("htree_dump_leaf_inode", errcode,
  77                                 "while getting rec_len for block %lu",
  78                                 (unsigned long) blk);
  79                         return;
  80                 }
  81                 thislen = ext2fs_dirent_name_len(dirent);
  82                 if (((offset + rec_len) > fs->blocksize) ||
  83                     (rec_len < 8) ||
  84                     ((rec_len % 4) != 0) ||
  85                     ((unsigned) thislen + 8 > rec_len)) {
  86                         fprintf(pager, "Corrupted directory block (%llu)!\n",
  87                                 blk);
  88                         break;
  89                 }
  90                 strncpy(name, dirent->name, thislen);
  91                 name[thislen] = '\0';
  92                 errcode = ext2fs_dirhash(hash_alg, name,
  93                                          thislen, fs->super->s_hash_seed,
  94                                          &hash, &minor_hash);
  95                 if (errcode)
  96                         com_err("htree_dump_leaf_node", errcode,
  97                                 "while calculating hash");
  98                 if ((offset == fs->blocksize - csum_size) &&
  99                     (dirent->inode == 0) &&
 100                     (dirent->rec_len == csum_size) &&
 101                     (dirent->name_len == EXT2_DIR_NAME_LEN_CSUM)) {
 102                         struct ext2_dir_entry_tail *t;
 103
 104                         t = (struct ext2_dir_entry_tail *) dirent;
 105
 106                         snprintf(tmp, EXT2_NAME_LEN + 64,
 107                                  "leaf block checksum: 0x%08x  ",
 108                                  t->det_checksum);
 109                 } else {
 110                         snprintf(tmp, EXT2_NAME_LEN + 64,
 111                                  "%u 0x%08x-%08x (%d) %s   ",
 112                                  dirent->inode, hash, minor_hash,
 113                                  rec_len, name);
 114                 }
 115                 thislen = strlen(tmp);
 116                 if (col + thislen > 80) {
 117                         fprintf(pager, "\n");
 118                         col = 0;
 119                 }
 120                 fprintf(pager, "%s", tmp);
 121                 col += thislen;
 122                 offset += rec_len;
 123         }
 124         fprintf(pager, "\n");
 125 }
 126
 127
 128 static void htree_dump_int_block(ext2_filsys fs, ext2_ino_t ino,
 129                                  struct ext2_inode *inode,
 130                                  struct ext2_dx_root_info * rootnode,
 131                                  blk64_t blk, char *buf, int level);
 132
 133
 134 static void htree_dump_int_node(ext2_filsys fs, ext2_ino_t ino,
 135                                 struct ext2_inode *inode,
 136                                 struct ext2_dx_root_info * rootnode,
 137                                 struct ext2_dx_entry *ent,
 138                                 char *buf, int level)
 139 {
 140         struct ext2_dx_countlimit       dx_countlimit;
 141         struct ext2_dx_tail             *tail;
 142         int                             hash, i;
 143         int                             limit, count;
 144         int                             remainder;
 145
 146         dx_countlimit = *((struct ext2_dx_countlimit *) ent);
 147         count = ext2fs_le16_to_cpu(dx_countlimit.count);
 148         limit = ext2fs_le16_to_cpu(dx_countlimit.limit);
 149
 150         fprintf(pager, "Number of entries (count): %d\n", count);
 151         fprintf(pager, "Number of entries (limit): %d\n", limit);
 152
 153         remainder = fs->blocksize - (limit * sizeof(struct ext2_dx_entry));
 154         if (ent == (struct ext2_dx_entry *)(rootnode + 1))
 155                 remainder -= sizeof(struct ext2_dx_root_info) + 24;
 156         else
 157                 remainder -= 8;
 158         if (ext2fs_has_feature_metadata_csum(fs->super) &&
 159             remainder == sizeof(struct ext2_dx_tail)) {
 160                 tail = (struct ext2_dx_tail *)(ent + limit);
 161                 fprintf(pager, "Checksum: 0x%08x\n",
 162                         ext2fs_le32_to_cpu(tail->dt_checksum));
 163         }
 164
 165         for (i=0; i < count; i++) {
 166                 hash = i ? ext2fs_le32_to_cpu(ent[i].hash) : 0;
 167                 fprintf(pager, "Entry #%d: Hash 0x%08x%s, block %u\n", i,
 168                         hash, (hash & 1) ? " (**)" : "",
 169                         ext2fs_le32_to_cpu(ent[i].block));
 170                 }
 171
 172         fprintf(pager, "\n");
 173
 174         for (i=0; i < count; i++) {
 175                 unsigned int hashval, block;
 176
 177                 hashval = ext2fs_le32_to_cpu(ent[i].hash);
 178                 block = ext2fs_le32_to_cpu(ent[i].block);
 179                 fprintf(pager, "Entry #%d: Hash 0x%08x, block %u\n", i,
 180                        i ? hashval : 0, block);
 181                 if (level)
 182                         htree_dump_int_block(fs, ino, inode, rootnode,
 183                                              block, buf, level-1);
 184                 else
 185                         htree_dump_leaf_node(fs, ino, inode, rootnode,
 186                                              block, buf);
 187         }
 188
 189         fprintf(pager, "---------------------\n");
 190 }
 191
 192 static void htree_dump_int_block(ext2_filsys fs, ext2_ino_t ino,
 193                                  struct ext2_inode *inode,
 194                                  struct ext2_dx_root_info * rootnode,
 195                                  blk64_t blk, char *buf, int level)
 196 {
 197         char            *cbuf;
 198         errcode_t       errcode;
 199         blk64_t         pblk;
 200
 201         cbuf = malloc(fs->blocksize);
 202         if (!cbuf) {
 203                 fprintf(pager, "Couldn't allocate child block.\n");
 204                 return;
 205         }
 206
 207         errcode = ext2fs_bmap2(fs, ino, inode, buf, 0, blk, 0, &pblk);
 208         if (errcode) {
 209                 com_err("htree_dump_int_block", errcode,
 210                         "while mapping logical block %llu\n", blk);
 211                 goto errout;
 212         }
 213
 214         errcode = io_channel_read_blk64(current_fs->io, pblk, 1, buf);
 215         if (errcode) {
 216                 com_err("htree_dump_int_block", errcode,
 217                         "while  reading block %llu\n", blk);
 218                 goto errout;
 219         }
 220
 221         htree_dump_int_node(fs, ino, inode, rootnode,
 222                             (struct ext2_dx_entry *) (buf+8),
 223                             cbuf, level);
 224 errout:
 225         free(cbuf);
 226 }
 227
 228
 229
 230 void do_htree_dump(int argc, char *argv[], int sci_idx EXT2FS_ATTR((unused)),
 231                    void *infop EXT2FS_ATTR((unused)))
 232 {
 233         ext2_ino_t      ino;
 234         struct ext2_inode inode;
 235         blk64_t         blk;
 236         char            *buf = NULL;
 237         struct          ext2_dx_root_info  *rootnode;
 238         struct          ext2_dx_entry *ent;
 239         errcode_t       errcode;
 240
 241         if (check_fs_open(argv[0]))
 242                 return;
 243
 244         pager = open_pager();
 245
 246         if (common_inode_args_process(argc, argv, &ino, 0))
 247                 goto errout;
 248
 249         if (debugfs_read_inode(ino, &inode, argv[1]))
 250                 goto errout;
 251
 252         if (!LINUX_S_ISDIR(inode.i_mode)) {
 253                 com_err(argv[0], 0, "Not a directory");
 254                 goto errout;
 255         }
 256
 257         if ((inode.i_flags & EXT2_BTREE_FL) == 0) {
 258                 com_err(argv[0], 0, "Not a hash-indexed directory");
 259                 goto errout;
 260         }
 261
 262         buf = malloc(2*current_fs->blocksize);
 263         if (!buf) {
 264                 com_err(argv[0], 0, "Couldn't allocate htree buffer");
 265                 goto errout;
 266         }
 267
 268         errcode = ext2fs_bmap2(current_fs, ino, &inode, buf, 0, 0, 0, &blk);
 269         if (errcode) {
 270                 com_err("do_htree_block", errcode,
 271                         "while mapping logical block 0\n");
 272                 goto errout;
 273         }
 274
 275         errcode = io_channel_read_blk64(current_fs->io, blk,
 276                                         1, buf);
 277         if (errcode) {
 278                 com_err(argv[0], errcode, "Error reading root node");
 279                 goto errout;
 280         }
 281
 282         rootnode = (struct ext2_dx_root_info *) (buf + 24);
 283
 284         fprintf(pager, "Root node dump:\n");
 285         fprintf(pager, "\t Reserved zero: %u\n", rootnode->reserved_zero);
 286         fprintf(pager, "\t Hash Version: %d\n", rootnode->hash_version);
 287         fprintf(pager, "\t Info length: %d\n", rootnode->info_length);
 288         fprintf(pager, "\t Indirect levels: %d\n", rootnode->indirect_levels);
 289         fprintf(pager, "\t Flags: %d\n", rootnode->unused_flags);
 290
 291         ent = (struct ext2_dx_entry *)
 292                 ((char *)rootnode + 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[], int sci_idx EXT2FS_ATTR((unused)),
 307                 void *infop EXT2FS_ATTR((unused)))
 308 {
 309         ext2_dirhash_t hash, minor_hash;
 310         errcode_t       err;
 311         int             c;
 312         int             hash_version = 0;
 313         __u32           hash_seed[4];
 314
 315         hash_seed[0] = hash_seed[1] = hash_seed[2] = hash_seed[3] = 0;
 316
 317         reset_getopt();
 318         while ((c = getopt (argc, argv, "h:s:")) != EOF) {
 319                 switch (c) {
 320                 case 'h':
 321                         hash_version = e2p_string2hash(optarg);
 322                         if (hash_version < 0)
 323                                 hash_version = atoi(optarg);
 324                         break;
 325                 case 's':
 326                         if (uuid_parse(optarg, (unsigned char *) hash_seed)) {
 327                                 fprintf(stderr, "Invalid UUID format: %s\n",
 328                                         optarg);
 329                                 return;
 330                         }
 331                         break;
 332                 default:
 333                         goto print_usage;
 334                 }
 335         }
 336         if (optind != argc-1) {
 337         print_usage:
 338                 com_err(argv[0], 0, "usage: dx_hash [-h hash_alg] "
 339                         "[-s hash_seed] filename");
 340                 return;
 341         }
 342         err = ext2fs_dirhash(hash_version, argv[optind], strlen(argv[optind]),
 343                              hash_seed, &hash, &minor_hash);
 344         if (err) {
 345                 com_err(argv[0], err, "while calculating hash");
 346                 return;
 347         }
 348         printf("Hash of %s is 0x%0x (minor 0x%0x)\n", argv[optind],
 349                hash, minor_hash);
 350 }
 351
 352 /*
 353  * Search for particular directory entry (useful for debugging very
 354  * large hash tree directories that have lost some blocks from the
 355  * btree index).
 356  */
 357 struct process_block_struct {
 358         char    *search_name;
 359         char    *buf;
 360         int     len;
 361 };
 362
 363 static int search_dir_block(ext2_filsys fs, blk64_t *blocknr,
 364                             e2_blkcnt_t blockcnt, blk64_t ref_blk,
 365                             int ref_offset, void *priv_data);
 366
 367 void do_dirsearch(int argc, char *argv[], int sci_idx EXT2FS_ATTR((unused)),
 368                   void *infop EXT2FS_ATTR((unused)))
 369 {
 370         ext2_ino_t      inode;
 371         struct process_block_struct pb;
 372
 373         if (check_fs_open(argv[0]))
 374                 return;
 375
 376         if (argc != 3) {
 377                 com_err(0, 0, "Usage: dirsearch dir filename");
 378                 return;
 379         }
 380
 381         inode = string_to_inode(argv[1]);
 382         if (!inode)
 383                 return;
 384
 385         pb.buf = malloc(current_fs->blocksize);
 386         if (!pb.buf) {
 387                 com_err("dirsearch", 0, "Couldn't allocate buffer");
 388                 return;
 389         }
 390         pb.search_name = argv[2];
 391         pb.len = strlen(pb.search_name);
 392
 393         ext2fs_block_iterate3(current_fs, inode, BLOCK_FLAG_READ_ONLY, 0,
 394                               search_dir_block, &pb);
 395
 396         free(pb.buf);
 397 }
 398
 399
 400 static int search_dir_block(ext2_filsys fs, blk64_t *blocknr,
 401                             e2_blkcnt_t blockcnt,
 402                             blk64_t ref_blk EXT2FS_ATTR((unused)),
 403                             int ref_offset EXT2FS_ATTR((unused)),
 404                             void *priv_data)
 405 {
 406         struct process_block_struct *p;
 407         struct ext2_dir_entry *dirent;
 408         errcode_t               errcode;
 409         unsigned int            offset = 0;
 410         unsigned int            rec_len;
 411
 412         if (blockcnt < 0)
 413                 return 0;
 414
 415         p = (struct process_block_struct *) priv_data;
 416
 417         errcode = io_channel_read_blk64(current_fs->io, *blocknr, 1, p->buf);
 418         if (errcode) {
 419                 com_err("search_dir_block", errcode,
 420                         "while reading block %lu", (unsigned long) *blocknr);
 421                 return BLOCK_ABORT;
 422         }
 423
 424         while (offset < fs->blocksize) {
 425                 dirent = (struct ext2_dir_entry *) (p->buf + offset);
 426                 errcode = ext2fs_get_rec_len(fs, dirent, &rec_len);
 427                 if (errcode) {
 428                         com_err("htree_dump_leaf_inode", errcode,
 429                                 "while getting rec_len for block %lu",
 430                                 (unsigned long) *blocknr);
 431                         return BLOCK_ABORT;
 432                 }
 433                 if (dirent->inode &&
 434                     p->len == ext2fs_dirent_name_len(dirent) &&
 435                     strncmp(p->search_name, dirent->name,
 436                             p->len) == 0) {
 437                         printf("Entry found at logical block %lld, "
 438                                "phys %llu, offset %u\n", (long long)blockcnt,
 439                                *blocknr, offset);
 440                         printf("offset %u\n", offset);
 441                         return BLOCK_ABORT;
 442                 }
 443                 offset += rec_len;
 444         }
 445         return 0;
 446 }
 447