Home | History | Annotate | Download | only in debugfs
      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 #include "uuid/uuid.h"
     27 #include "e2p/e2p.h"
     28 
     29 static FILE *pager;
     30 
     31 static void htree_dump_leaf_node(ext2_filsys fs, ext2_ino_t ino,
     32 				 struct ext2_inode *inode,
     33 				 struct ext2_dx_root_info * rootnode,
     34 				 blk_t blk, char *buf)
     35 {
     36 	errcode_t	errcode;
     37 	struct ext2_dir_entry *dirent;
     38 	int		thislen, col = 0;
     39 	unsigned int	offset = 0;
     40 	char		name[EXT2_NAME_LEN + 1];
     41 	char		tmp[EXT2_NAME_LEN + 16];
     42 	blk_t		pblk;
     43 	ext2_dirhash_t 	hash, minor_hash;
     44 	unsigned int	rec_len;
     45 	int		hash_alg;
     46 
     47 	errcode = ext2fs_bmap(fs, ino, inode, buf, 0, blk, &pblk);
     48 	if (errcode) {
     49 		com_err("htree_dump_leaf_node", errcode,
     50 			"while mapping logical block %u\n", blk);
     51 		return;
     52 	}
     53 
     54 	printf("Reading directory block %lu, phys %lu\n",
     55 	       (unsigned long) blk, (unsigned long) pblk);
     56 	errcode = ext2fs_read_dir_block2(current_fs, pblk, buf, 0);
     57 	if (errcode) {
     58 		com_err("htree_dump_leaf_node", errcode,
     59 			"while reading block %lu (%lu)\n",
     60 			(unsigned long) blk, (unsigned long) pblk);
     61 		return;
     62 	}
     63 	hash_alg = rootnode->hash_version;
     64 	if ((hash_alg <= EXT2_HASH_TEA) &&
     65 	    (fs->super->s_flags & EXT2_FLAGS_UNSIGNED_HASH))
     66 		hash_alg += 3;
     67 
     68 	while (offset < fs->blocksize) {
     69 		dirent = (struct ext2_dir_entry *) (buf + offset);
     70 		errcode = ext2fs_get_rec_len(fs, dirent, &rec_len);
     71 		if (errcode) {
     72 			com_err("htree_dump_leaf_inode", errcode,
     73 				"while getting rec_len for block %lu",
     74 				(unsigned long) blk);
     75 			return;
     76 		}
     77 		if (((offset + rec_len) > fs->blocksize) ||
     78 		    (rec_len < 8) ||
     79 		    ((rec_len % 4) != 0) ||
     80 		    ((((unsigned) dirent->name_len & 0xFF)+8) > rec_len)) {
     81 			fprintf(pager, "Corrupted directory block (%u)!\n", blk);
     82 			break;
     83 		}
     84 		thislen = ((dirent->name_len & 0xFF) < EXT2_NAME_LEN) ?
     85 			(dirent->name_len & 0xFF) : EXT2_NAME_LEN;
     86 		strncpy(name, dirent->name, thislen);
     87 		name[thislen] = '\0';
     88 		errcode = ext2fs_dirhash(hash_alg, name,
     89 					 thislen, fs->super->s_hash_seed,
     90 					 &hash, &minor_hash);
     91 		if (errcode)
     92 			com_err("htree_dump_leaf_node", errcode,
     93 				"while calculating hash");
     94 		sprintf(tmp, "%u 0x%08x-%08x (%d) %s   ", dirent->inode,
     95 			hash, minor_hash, rec_len, name);
     96 		thislen = strlen(tmp);
     97 		if (col + thislen > 80) {
     98 			fprintf(pager, "\n");
     99 			col = 0;
    100 		}
    101 		fprintf(pager, "%s", tmp);
    102 		col += thislen;
    103 		offset += rec_len;
    104 	}
    105 	fprintf(pager, "\n");
    106 }
    107 
    108 
    109 static void htree_dump_int_block(ext2_filsys fs, ext2_ino_t ino,
    110 				 struct ext2_inode *inode,
    111 				 struct ext2_dx_root_info * rootnode,
    112 				 blk_t blk, char *buf, int level);
    113 
    114 
    115 static void htree_dump_int_node(ext2_filsys fs, ext2_ino_t ino,
    116 				struct ext2_inode *inode,
    117 				struct ext2_dx_root_info * rootnode,
    118 				struct ext2_dx_entry *ent,
    119 				char *buf, int level)
    120 {
    121 	struct ext2_dx_countlimit	limit;
    122 	struct ext2_dx_entry		e;
    123 	int				hash, i;
    124 
    125 
    126 	limit = *((struct ext2_dx_countlimit *) ent);
    127 	limit.count = ext2fs_le16_to_cpu(limit.count);
    128 	limit.limit = ext2fs_le16_to_cpu(limit.limit);
    129 
    130 	fprintf(pager, "Number of entries (count): %d\n", limit.count);
    131 	fprintf(pager, "Number of entries (limit): %d\n", limit.limit);
    132 
    133 	for (i=0; i < limit.count; i++) {
    134 		hash = i ? ext2fs_le32_to_cpu(ent[i].hash) : 0;
    135 		fprintf(pager, "Entry #%d: Hash 0x%08x%s, block %u\n", i,
    136 			hash, (hash & 1) ? " (**)" : "",
    137 			ext2fs_le32_to_cpu(ent[i].block));
    138 		}
    139 
    140 	fprintf(pager, "\n");
    141 
    142 	for (i=0; i < limit.count; i++) {
    143 		e.hash = ext2fs_le32_to_cpu(ent[i].hash);
    144 		e.block = ext2fs_le32_to_cpu(ent[i].block);
    145 		fprintf(pager, "Entry #%d: Hash 0x%08x, block %u\n", i,
    146 		       i ? e.hash : 0, e.block);
    147 		if (level)
    148 			htree_dump_int_block(fs, ino, inode, rootnode,
    149 					     e.block, buf, level-1);
    150 		else
    151 			htree_dump_leaf_node(fs, ino, inode, rootnode,
    152 					     e.block, buf);
    153 	}
    154 
    155 	fprintf(pager, "---------------------\n");
    156 }
    157 
    158 static void htree_dump_int_block(ext2_filsys fs, ext2_ino_t ino,
    159 				 struct ext2_inode *inode,
    160 				 struct ext2_dx_root_info * rootnode,
    161 				 blk_t blk, char *buf, int level)
    162 {
    163 	char		*cbuf;
    164 	errcode_t	errcode;
    165 	blk_t		pblk;
    166 
    167 	cbuf = malloc(fs->blocksize);
    168 	if (!cbuf) {
    169 		fprintf(pager, "Couldn't allocate child block.\n");
    170 		return;
    171 	}
    172 
    173 	errcode = ext2fs_bmap(fs, ino, inode, buf, 0, blk, &pblk);
    174 	if (errcode) {
    175 		com_err("htree_dump_int_block", errcode,
    176 			"while mapping logical block %u\n", blk);
    177 		goto errout;
    178 	}
    179 
    180 	errcode = io_channel_read_blk(current_fs->io, pblk, 1, buf);
    181 	if (errcode) {
    182 		com_err("htree_dump_int_block", errcode,
    183 			"while 	reading block %u\n", blk);
    184 		goto errout;
    185 	}
    186 
    187 	htree_dump_int_node(fs, ino, inode, rootnode,
    188 			    (struct ext2_dx_entry *) (buf+8),
    189 			    cbuf, level);
    190 errout:
    191 	free(cbuf);
    192 }
    193 
    194 
    195 
    196 void do_htree_dump(int argc, char *argv[])
    197 {
    198 	ext2_ino_t	ino;
    199 	struct ext2_inode inode;
    200 	int		c;
    201 	int		long_opt = 0;
    202 	blk_t		blk;
    203 	char		*buf = NULL;
    204 	struct 		ext2_dx_root_info  *rootnode;
    205 	struct 		ext2_dx_entry *ent;
    206 	struct		ext2_dx_countlimit *limit;
    207 	errcode_t	errcode;
    208 
    209 	if (check_fs_open(argv[0]))
    210 		return;
    211 
    212 	pager = open_pager();
    213 
    214 	reset_getopt();
    215 	while ((c = getopt (argc, argv, "l")) != EOF) {
    216 		switch (c) {
    217 		case 'l':
    218 			long_opt++;
    219 			break;
    220 		default:
    221 			goto print_usage;
    222 		}
    223 	}
    224 
    225 	if (argc > optind+1) {
    226 	print_usage:
    227 		com_err(0, 0, "Usage: htree_dump [-l] file");
    228 		goto errout;
    229 	}
    230 
    231 	if (argc == optind)
    232 		ino = cwd;
    233 	else
    234 		ino = string_to_inode(argv[optind]);
    235 	if (!ino)
    236 		goto errout;
    237 
    238 	if (debugfs_read_inode(ino, &inode, argv[1]))
    239 		goto errout;
    240 
    241 	if (!LINUX_S_ISDIR(inode.i_mode)) {
    242 		com_err(argv[0], 0, "Not a directory");
    243 		goto errout;
    244 	}
    245 
    246 	if ((inode.i_flags & EXT2_BTREE_FL) == 0) {
    247 		com_err(argv[0], 0, "Not a hash-indexed directory");
    248 		goto errout;
    249 	}
    250 
    251 	buf = malloc(2*current_fs->blocksize);
    252 	if (!buf) {
    253 		com_err(argv[0], 0, "Couldn't allocate htree buffer");
    254 		goto errout;
    255 	}
    256 
    257 	errcode = ext2fs_bmap(current_fs, ino, &inode, buf, 0, 0, &blk);
    258 	if (errcode) {
    259 		com_err("do_htree_block", errcode,
    260 			"while mapping logical block 0\n");
    261 		goto errout;
    262 	}
    263 
    264 	errcode = io_channel_read_blk(current_fs->io, blk,
    265 				      1, buf);
    266 	if (errcode) {
    267 		com_err(argv[0], errcode, "Error reading root node");
    268 		goto errout;
    269 	}
    270 
    271 	rootnode = (struct ext2_dx_root_info *) (buf + 24);
    272 
    273 	fprintf(pager, "Root node dump:\n");
    274 	fprintf(pager, "\t Reserved zero: %u\n", rootnode->reserved_zero);
    275 	fprintf(pager, "\t Hash Version: %d\n", rootnode->hash_version);
    276 	fprintf(pager, "\t Info length: %d\n", rootnode->info_length);
    277 	fprintf(pager, "\t Indirect levels: %d\n", rootnode->indirect_levels);
    278 	fprintf(pager, "\t Flags: %d\n", rootnode->unused_flags);
    279 
    280 	ent = (struct ext2_dx_entry *) (buf + 24 + rootnode->info_length);
    281 	limit = (struct ext2_dx_countlimit *) ent;
    282 
    283 	htree_dump_int_node(current_fs, ino, &inode, rootnode, ent,
    284 			    buf + current_fs->blocksize,
    285 			    rootnode->indirect_levels);
    286 
    287 errout:
    288 	free(buf);
    289 	close_pager(pager);
    290 }
    291 
    292 /*
    293  * This function prints the hash of a given file.
    294  */
    295 void do_dx_hash(int argc, char *argv[])
    296 {
    297 	ext2_dirhash_t hash, minor_hash;
    298 	errcode_t	err;
    299 	int		c;
    300 	int		hash_version = 0;
    301 	__u32		hash_seed[4];
    302 
    303 	hash_seed[0] = hash_seed[1] = hash_seed[2] = hash_seed[3] = 0;
    304 
    305 	reset_getopt();
    306 	while ((c = getopt (argc, argv, "h:s:")) != EOF) {
    307 		switch (c) {
    308 		case 'h':
    309 			hash_version = e2p_string2hash(optarg);
    310 			if (hash_version < 0)
    311 				hash_version = atoi(optarg);
    312 			break;
    313 		case 's':
    314 			if (uuid_parse(optarg, (unsigned char *) hash_seed)) {
    315 				fprintf(stderr, "Invalid UUID format: %s\n",
    316 					optarg);
    317 				return;
    318 			}
    319 			break;
    320 		default:
    321 			goto print_usage;
    322 		}
    323 	}
    324 	if (optind != argc-1) {
    325 	print_usage:
    326 		com_err(argv[0], 0, "usage: dx_hash [-h hash_alg] "
    327 			"[-s hash_seed] filename");
    328 		return;
    329 	}
    330 	err = ext2fs_dirhash(hash_version, argv[optind], strlen(argv[optind]),
    331 			     hash_seed, &hash, &minor_hash);
    332 	if (err) {
    333 		com_err(argv[0], err, "while caclulating hash");
    334 		return;
    335 	}
    336 	printf("Hash of %s is 0x%0x (minor 0x%0x)\n", argv[optind],
    337 	       hash, minor_hash);
    338 }
    339 
    340 /*
    341  * Search for particular directory entry (useful for debugging very
    342  * large hash tree directories that have lost some blocks from the
    343  * btree index).
    344  */
    345 struct process_block_struct {
    346 	char	*search_name;
    347 	char	*buf;
    348 	int	len;
    349 };
    350 
    351 static int search_dir_block(ext2_filsys fs, blk_t *blocknr,
    352 			    e2_blkcnt_t blockcnt, blk_t ref_blk,
    353 			    int ref_offset, void *priv_data);
    354 
    355 void do_dirsearch(int argc, char *argv[])
    356 {
    357 	ext2_ino_t	inode;
    358 	struct process_block_struct pb;
    359 
    360 	if (check_fs_open(argv[0]))
    361 		return;
    362 
    363 	if (argc != 3) {
    364 		com_err(0, 0, "Usage: dirsearch dir filename");
    365 		return;
    366 	}
    367 
    368 	inode = string_to_inode(argv[1]);
    369 	if (!inode)
    370 		return;
    371 
    372 	pb.buf = malloc(current_fs->blocksize);
    373 	if (!pb.buf) {
    374 		com_err("dirsearch", 0, "Couldn't allocate buffer");
    375 		return;
    376 	}
    377 	pb.search_name = argv[2];
    378 	pb.len = strlen(pb.search_name);
    379 
    380 	ext2fs_block_iterate2(current_fs, inode, BLOCK_FLAG_READ_ONLY, 0,
    381 			      search_dir_block, &pb);
    382 
    383 	free(pb.buf);
    384 }
    385 
    386 
    387 static int search_dir_block(ext2_filsys fs, blk_t *blocknr,
    388 			    e2_blkcnt_t blockcnt,
    389 			    blk_t ref_blk EXT2FS_ATTR((unused)),
    390 			    int ref_offset EXT2FS_ATTR((unused)),
    391 			    void *priv_data)
    392 {
    393 	struct process_block_struct *p;
    394 	struct ext2_dir_entry *dirent;
    395 	errcode_t	       	errcode;
    396 	unsigned int		offset = 0;
    397 	unsigned int		rec_len;
    398 
    399 	if (blockcnt < 0)
    400 		return 0;
    401 
    402 	p = (struct process_block_struct *) priv_data;
    403 
    404 	errcode = io_channel_read_blk(current_fs->io, *blocknr, 1, p->buf);
    405 	if (errcode) {
    406 		com_err("search_dir_block", errcode,
    407 			"while reading block %lu", (unsigned long) *blocknr);
    408 		return BLOCK_ABORT;
    409 	}
    410 
    411 	while (offset < fs->blocksize) {
    412 		dirent = (struct ext2_dir_entry *) (p->buf + offset);
    413 		errcode = ext2fs_get_rec_len(fs, dirent, &rec_len);
    414 		if (errcode) {
    415 			com_err("htree_dump_leaf_inode", errcode,
    416 				"while getting rec_len for block %lu",
    417 				(unsigned long) *blocknr);
    418 			return BLOCK_ABORT;
    419 		}
    420 		if (dirent->inode &&
    421 		    p->len == (dirent->name_len & 0xFF) &&
    422 		    strncmp(p->search_name, dirent->name,
    423 			    p->len) == 0) {
    424 			printf("Entry found at logical block %lld, "
    425 			       "phys %u, offset %u\n", (long long)blockcnt,
    426 			       *blocknr, offset);
    427 			printf("offset %u\n", offset);
    428 			return BLOCK_ABORT;
    429 		}
    430 		offset += rec_len;
    431 	}
    432 	return 0;
    433 }
    434 
    435