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 #include "ext2fs/nls.h"
  31
  32 static FILE *pager;
  33
  34 static void htree_dump_leaf_node(ext2_filsys fs, ext2_ino_t ino,
  35                                  struct ext2_inode *inode,
  36                                  struct ext2_dx_root_info * rootnode,
  37                                  blk64_t blk, char *buf)
  38 {
  39         errcode_t       errcode;
  40         struct ext2_dir_entry *dirent;
  41         int             thislen, col = 0;
  42         unsigned int    offset = 0;
  43         char            name[EXT2_NAME_LEN + 1];
  44         char            tmp[EXT2_NAME_LEN + 64];
  45         blk64_t         pblk;
  46         ext2_dirhash_t  hash, minor_hash;
  47         unsigned int    rec_len;
  48         int             hash_alg;
  49         int             hash_flags = inode->i_flags & EXT4_CASEFOLD_FL;
  50         int             csum_size = 0;
  51
  52         if (ext2fs_has_feature_metadata_csum(fs->super))
  53                 csum_size = sizeof(struct ext2_dir_entry_tail);
  54
  55         errcode = ext2fs_bmap2(fs, ino, inode, buf, 0, blk, 0, &pblk);
  56         if (errcode) {
  57                 com_err("htree_dump_leaf_node", errcode,
  58                         "while mapping logical block %llu\n", blk);
  59                 return;
  60         }
  61
  62         fprintf(pager, "Reading directory block %llu, phys %llu\n", blk, 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                         blk, 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                                 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,
 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\n",
 166                         ext2fs_le32_to_cpu(tail->dt_checksum));
 167         }
 168
 169         for (i=0; i < count; i++) {
 170                 hash = i ? ext2fs_le32_to_cpu(ent[i].hash) : 0;
 171                 fprintf(pager, "Entry #%d: Hash 0x%08x%s, block %u\n", i,
 172                         hash, (hash & 1) ? " (**)" : "",
 173                         ext2fs_le32_to_cpu(ent[i].block));
 174                 }
 175
 176         fprintf(pager, "\n");
 177
 178         for (i=0; i < count; i++) {
 179                 unsigned int hashval, block;
 180
 181                 hashval = ext2fs_le32_to_cpu(ent[i].hash);
 182                 block = ext2fs_le32_to_cpu(ent[i].block);
 183                 fprintf(pager, "Entry #%d: Hash 0x%08x, block %u\n", i,
 184                        i ? hashval : 0, block);
 185                 if (level)
 186                         htree_dump_int_block(fs, ino, inode, rootnode,
 187                                              block, buf, level-1);
 188                 else
 189                         htree_dump_leaf_node(fs, ino, inode, rootnode,
 190                                              block, buf);
 191         }
 192
 193         fprintf(pager, "---------------------\n");
 194 }
 195
 196 static void htree_dump_int_block(ext2_filsys fs, ext2_ino_t ino,
 197                                  struct ext2_inode *inode,
 198                                  struct ext2_dx_root_info * rootnode,
 199                                  blk64_t blk, char *buf, int level)
 200 {
 201         char            *cbuf;
 202         errcode_t       errcode;
 203         blk64_t         pblk;
 204
 205         cbuf = malloc(fs->blocksize);
 206         if (!cbuf) {
 207                 fprintf(pager, "Couldn't allocate child block.\n");
 208                 return;
 209         }
 210
 211         errcode = ext2fs_bmap2(fs, ino, inode, buf, 0, blk, 0, &pblk);
 212         if (errcode) {
 213                 com_err("htree_dump_int_block", errcode,
 214                         "while mapping logical block %llu\n", blk);
 215                 goto errout;
 216         }
 217
 218         errcode = io_channel_read_blk64(current_fs->io, pblk, 1, buf);
 219         if (errcode) {
 220                 com_err("htree_dump_int_block", errcode,
 221                         "while  reading block %llu\n", blk);
 222                 goto errout;
 223         }
 224
 225         htree_dump_int_node(fs, ino, inode, rootnode,
 226                             (struct ext2_dx_entry *) (buf+8),
 227                             cbuf, level);
 228 errout:
 229         free(cbuf);
 230 }
 231
 232
 233
 234 void do_htree_dump(int argc, char *argv[], int sci_idx EXT2FS_ATTR((unused)),
 235                    void *infop EXT2FS_ATTR((unused)))
 236 {
 237         ext2_ino_t      ino;
 238         struct ext2_inode inode;
 239         blk64_t         blk;
 240         char            *buf = NULL;
 241         struct          ext2_dx_root_info  *rootnode;
 242         struct          ext2_dx_entry *ent;
 243         errcode_t       errcode;
 244
 245         if (check_fs_open(argv[0]))
 246                 return;
 247
 248         pager = open_pager();
 249
 250         if (common_inode_args_process(argc, argv, &ino, 0))
 251                 goto errout;
 252
 253         if (debugfs_read_inode(ino, &inode, argv[1]))
 254                 goto errout;
 255
 256         if (!LINUX_S_ISDIR(inode.i_mode)) {
 257                 com_err(argv[0], 0, "Not a directory");
 258                 goto errout;
 259         }
 260
 261         if ((inode.i_flags & EXT2_BTREE_FL) == 0) {
 262                 com_err(argv[0], 0, "Not a hash-indexed directory");
 263                 goto errout;
 264         }
 265
 266         buf = malloc(2*current_fs->blocksize);
 267         if (!buf) {
 268                 com_err(argv[0], 0, "Couldn't allocate htree buffer");
 269                 goto errout;
 270         }
 271
 272         errcode = ext2fs_bmap2(current_fs, ino, &inode, buf, 0, 0, 0, &blk);
 273         if (errcode) {
 274                 com_err("do_htree_block", errcode,
 275                         "while mapping logical block 0\n");
 276                 goto errout;
 277         }
 278
 279         errcode = io_channel_read_blk64(current_fs->io, blk,
 280                                         1, buf);
 281         if (errcode) {
 282                 com_err(argv[0], errcode, "Error reading root node");
 283                 goto errout;
 284         }
 285
 286         rootnode = (struct ext2_dx_root_info *) (buf + 24);
 287
 288         fprintf(pager, "Root node dump:\n");
 289         fprintf(pager, "\t Reserved zero: %u\n", rootnode->reserved_zero);
 290         fprintf(pager, "\t Hash Version: %d\n", rootnode->hash_version);
 291         fprintf(pager, "\t Info length: %d\n", rootnode->info_length);
 292         fprintf(pager, "\t Indirect levels: %d\n", rootnode->indirect_levels);
 293         fprintf(pager, "\t Flags: %d\n", rootnode->unused_flags);
 294
 295         ent = (struct ext2_dx_entry *)
 296                 ((char *)rootnode + rootnode->info_length);
 297
 298         htree_dump_int_node(current_fs, ino, &inode, rootnode, ent,
 299                             buf + current_fs->blocksize,
 300                             rootnode->indirect_levels);
 301
 302 errout:
 303         free(buf);
 304         close_pager(pager);
 305 }
 306
 307 /*
 308  * This function prints the hash of a given file.
 309  */
 310 void do_dx_hash(int argc, char *argv[], int sci_idx EXT2FS_ATTR((unused)),
 311                 void *infop EXT2FS_ATTR((unused)))
 312 {
 313         ext2_dirhash_t hash, minor_hash, hash_flags;
 314         errcode_t       err;
 315         int             c;
 316         int             hash_version = 0;
 317         __u32           hash_seed[4];
 318         const struct nls_table *encoding;
 319
 320         hash_seed[0] = hash_seed[1] = hash_seed[2] = hash_seed[3] = 0;
 321
 322         reset_getopt();
 323         while ((c = getopt (argc, argv, "h:s:")) != EOF) {
 324                 switch (c) {
 325                 case 'h':
 326                         hash_version = e2p_string2hash(optarg);
 327                         if (hash_version < 0)
 328                                 hash_version = atoi(optarg);
 329                         break;
 330                 case 's':
 331                         if (uuid_parse(optarg, (unsigned char *) hash_seed)) {
 332                                 fprintf(stderr, "Invalid UUID format: %s\n",
 333                                         optarg);
 334                                 return;
 335                         }
 336                         break;
 337                 case 'c':
 338                         hash_flags = EXT4_CASEFOLD_FL;
 339                         break;
 340                 case 'e':
 341                         encoding = nls_load_table(e2p_str2encoding(optarg));
 342                         if (!encoding)
 343                                 fprintf(stderr, "Invalid encoding: %s\n",
 344                                         optarg);
 345                                 return;
 346                 default:
 347                         goto print_usage;
 348                 }
 349         }
 350         if (optind != argc-1) {
 351         print_usage:
 352                 com_err(argv[0], 0, "usage: dx_hash [-h hash_alg] "
 353                         "[-s hash_seed] [-c] [-e encoding] filename");
 354                 return;
 355         }
 356         err = ext2fs_dirhash2(hash_version, argv[optind],
 357                               strlen(argv[optind]), encoding, hash_flags,
 358                               hash_seed, &hash, &minor_hash);
 359
 360         if (err) {
 361                 com_err(argv[0], err, "while calculating hash");
 362                 return;
 363         }
 364         printf("Hash of %s is 0x%0x (minor 0x%0x)\n", argv[optind],
 365                hash, minor_hash);
 366 }
 367
 368 /*
 369  * Search for particular directory entry (useful for debugging very
 370  * large hash tree directories that have lost some blocks from the
 371  * btree index).
 372  */
 373 struct process_block_struct {
 374         char    *search_name;
 375         char    *buf;
 376         int     len;
 377 };
 378
 379 static int search_dir_block(ext2_filsys fs, blk64_t *blocknr,
 380                             e2_blkcnt_t blockcnt, blk64_t ref_blk,
 381                             int ref_offset, void *priv_data);
 382
 383 void do_dirsearch(int argc, char *argv[], int sci_idx EXT2FS_ATTR((unused)),
 384                   void *infop EXT2FS_ATTR((unused)))
 385 {
 386         ext2_ino_t      inode;
 387         struct process_block_struct pb;
 388
 389         if (check_fs_open(argv[0]))
 390                 return;
 391
 392         if (argc != 3) {
 393                 com_err(0, 0, "Usage: dirsearch dir filename");
 394                 return;
 395         }
 396
 397         inode = string_to_inode(argv[1]);
 398         if (!inode)
 399                 return;
 400
 401         pb.buf = malloc(current_fs->blocksize);
 402         if (!pb.buf) {
 403                 com_err("dirsearch", 0, "Couldn't allocate buffer");
 404                 return;
 405         }
 406         pb.search_name = argv[2];
 407         pb.len = strlen(pb.search_name);
 408
 409         ext2fs_block_iterate3(current_fs, inode, BLOCK_FLAG_READ_ONLY, 0,
 410                               search_dir_block, &pb);
 411
 412         free(pb.buf);
 413 }
 414
 415
 416 static int search_dir_block(ext2_filsys fs, blk64_t *blocknr,
 417                             e2_blkcnt_t blockcnt,
 418                             blk64_t ref_blk EXT2FS_ATTR((unused)),
 419                             int ref_offset EXT2FS_ATTR((unused)),
 420                             void *priv_data)
 421 {
 422         struct process_block_struct *p;
 423         struct ext2_dir_entry *dirent;
 424         errcode_t               errcode;
 425         unsigned int            offset = 0;
 426         unsigned int            rec_len;
 427
 428         if (blockcnt < 0)
 429                 return 0;
 430
 431         p = (struct process_block_struct *) priv_data;
 432
 433         errcode = io_channel_read_blk64(current_fs->io, *blocknr, 1, p->buf);
 434         if (errcode) {
 435                 com_err("search_dir_block", errcode,
 436                         "while reading block %lu", (unsigned long) *blocknr);
 437                 return BLOCK_ABORT;
 438         }
 439
 440         while (offset < fs->blocksize) {
 441                 dirent = (struct ext2_dir_entry *) (p->buf + offset);
 442                 errcode = ext2fs_get_rec_len(fs, dirent, &rec_len);
 443                 if (errcode) {
 444                         com_err("htree_dump_leaf_inode", errcode,
 445                                 "while getting rec_len for block %lu",
 446                                 (unsigned long) *blocknr);
 447                         return BLOCK_ABORT;
 448                 }
 449                 if (dirent->inode &&
 450                     p->len == ext2fs_dirent_name_len(dirent) &&
 451                     strncmp(p->search_name, dirent->name,
 452                             p->len) == 0) {
 453                         printf("Entry found at logical block %lld, "
 454                                "phys %llu, offset %u\n", (long long)blockcnt,
 455                                *blocknr, offset);
 456                         printf("offset %u\n", offset);
 457                         return BLOCK_ABORT;
 458                 }
 459                 offset += rec_len;
 460         }
 461         return 0;
 462 }
 463