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