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