htree.c revision f77704e416fca7dbe4cc91abba674d2ae3c14f6f 
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
27static FILE *pager;
28
29static 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
96static 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
102static 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
145static 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
182void 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
265errout:
266	if (buf)
267		free(buf);
268	close_pager(pager);
269}
270
271/*
272 * This function prints the hash of a given file.
273 */
274void 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 */
314struct process_block_struct {
315	char	*search_name;
316	char	*buf;
317	int	len;
318};
319
320static 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
324void 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
355static 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
396