htree.c revision 65f0aab98b20b5994a726ab90d355248bcddfffd 
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
21extern int optind;
22extern char *optarg;
23#endif
24
25#include "debugfs.h"
26#include "uuid/uuid.h"
27#include "e2p/e2p.h"
28
29static FILE *pager;
30
31static 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
109static 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
115static 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
158static 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);
190errout:
191	free(cbuf);
192}
193
194
195
196void 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
287errout:
288	free(buf);
289	close_pager(pager);
290}
291
292/*
293 * This function prints the hash of a given file.
294 */
295void 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 */
345struct process_block_struct {
346	char	*search_name;
347	char	*buf;
348	int	len;
349};
350
351static 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
355void 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
387static 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