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