htree.c revision 503f9e7f6eb331c5b75d7f1ad126f71bcdcfb4e3 
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#ifdef HAVE_OPTRESET
25extern int optreset;		/* defined by BSD, but not others */
26#endif
27
28#include "debugfs.h"
29
30static FILE *pager;
31
32static 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 = io_channel_read_blk(current_fs->io, pblk, 1, buf);
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
93static 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
99static 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	int		i;
107
108	limit = (struct ext2_dx_countlimit *) ent;
109
110	fprintf(pager, "Number of entries (count): %d\n", limit->count);
111	fprintf(pager, "Number of entries (limit): %d\n", limit->limit);
112
113	for (i=0; i < limit->count; i++)
114		fprintf(pager, "Entry #%d: Hash 0x%08x, block %d\n", i,
115		       i ? ent[i].hash : 0, ent[i].block);
116
117	fprintf(pager, "\n");
118
119	for (i=0; i < limit->count; i++) {
120		fprintf(pager, "Entry #%d: Hash 0x%08x, block %d\n", i,
121		       i ? ent[i].hash : 0, ent[i].block);
122		if (level)
123			htree_dump_int_block(fs, ino, inode, root,
124					     ent[i].block, buf, level-1);
125		else
126			htree_dump_leaf_node(fs, ino, inode, root,
127					     ent[i].block, buf);
128	}
129
130	fprintf(pager, "---------------------\n");
131}
132
133static void htree_dump_int_block(ext2_filsys fs, ext2_ino_t ino,
134				 struct ext2_inode *inode,
135				 struct ext2_dx_root_info * root,
136				 blk_t blk, char *buf, int level)
137{
138	char		*cbuf;
139	errcode_t	errcode;
140	blk_t		pblk;
141
142	cbuf = malloc(fs->blocksize);
143	if (!cbuf) {
144		fprintf(pager, "Couldn't allocate child block.\n");
145		return;
146	}
147
148	errcode = ext2fs_bmap(fs, ino, inode, buf, 0, blk, &pblk);
149	if (errcode) {
150		com_err("htree_dump_int_block", errcode,
151			"while mapping logical block %d\n", blk);
152		return;
153	}
154
155	errcode = io_channel_read_blk(current_fs->io, pblk, 1, buf);
156	if (errcode) {
157		com_err("htree_dump_int_block", errcode,
158			"while 	reading block %d\n", blk);
159		return;
160	}
161
162	htree_dump_int_node(fs, ino, inode, root,
163			    (struct ext2_dx_entry *) (buf+8),
164			    cbuf, level);
165	free(cbuf);
166}
167
168
169
170void do_htree_dump(int argc, char *argv[])
171{
172	ext2_ino_t	ino;
173	struct ext2_inode inode;
174	int		retval;
175	int		i, c;
176	int		flags;
177	int		long_opt;
178	void		*buf = NULL;
179	struct 		ext2_dx_root_info  *root;
180	struct 		ext2_dx_entry *ent;
181	struct		ext2_dx_countlimit *limit;
182	errcode_t	errcode;
183
184	if (check_fs_open(argv[0]))
185		return;
186
187	pager = open_pager();
188
189	optind = 0;
190#ifdef HAVE_OPTRESET
191	optreset = 1;		/* Makes BSD getopt happy */
192#endif
193	while ((c = getopt (argc, argv, "l")) != EOF) {
194		switch (c) {
195		case 'l':
196			long_opt++;
197			break;
198		}
199	}
200
201	if (argc > optind+1) {
202		com_err(0, 0, "Usage: htree_dump [-l] file");
203		return;
204	}
205
206	if (argc == optind)
207		ino = cwd;
208	else
209		ino = string_to_inode(argv[optind]);
210	if (!ino)
211		return;
212
213	if (debugfs_read_inode(ino, &inode, argv[1]))
214		return;
215
216	if (!LINUX_S_ISDIR(inode.i_mode)) {
217		com_err(argv[0], 0, "Not a directory");
218		return;
219	}
220
221	if ((inode.i_flags & EXT2_BTREE_FL) == 0) {
222		com_err(argv[0], 0, "Not a hash-indexed directory");
223		return;
224	}
225
226	buf = malloc(2*current_fs->blocksize);
227	if (!buf) {
228		com_err(argv[0], 0, "Couldn't allocate htree buffer");
229		return;
230	}
231
232	errcode = io_channel_read_blk(current_fs->io, inode.i_block[0],
233				      1, buf);
234	if (errcode) {
235		com_err(argv[0], errcode, "Error reading root node");
236		goto errout;
237	}
238
239	root = (struct ext2_dx_root_info *) (buf + 24);
240
241	fprintf(pager, "Root node dump:\n");
242	fprintf(pager, "\t Reserved zero: %d\n", root->reserved_zero);
243	fprintf(pager, "\t Hash Version: %d\n", root->hash_version);
244	fprintf(pager, "\t Info length: %d\n", root->info_length);
245	fprintf(pager, "\t Indirect levels: %d\n", root->indirect_levels);
246	fprintf(pager, "\t Flags: %d\n", root->unused_flags);
247
248	ent = (struct ext2_dx_entry *) (buf + 24 + root->info_length);
249	limit = (struct ext2_dx_countlimit *) ent;
250
251	htree_dump_int_node(current_fs, ino, &inode, root, ent,
252			    buf + current_fs->blocksize,
253			    root->indirect_levels);
254
255errout:
256	if (buf)
257		free(buf);
258	close_pager(pager);
259}
260
261/*
262 * This function prints the hash of a given file.
263 */
264void do_dx_hash(int argc, char *argv[])
265{
266	ext2_dirhash_t hash, minor_hash;
267	errcode_t	err;
268	int		c;
269	int		hash_version = 0;
270	__u32		hash_seed[4];
271
272	hash_seed[0] = hash_seed[1] = hash_seed[2] = hash_seed[3] = 0;
273	optind = 0;
274#ifdef HAVE_OPTRESET
275	optreset = 1;		/* Makes BSD getopt happy */
276#endif
277	while ((c = getopt (argc, argv, "h:")) != EOF) {
278		switch (c) {
279		case 'h':
280			hash_version = atoi(optarg);
281			break;
282		}
283	}
284	if (optind != argc-1) {
285		com_err(argv[0], 0, "usage: dx_hash filename");
286		return;
287	}
288	err = ext2fs_dirhash(hash_version, argv[optind], strlen(argv[optind]),
289			     hash_seed, &hash, &minor_hash);
290	if (err) {
291		com_err(argv[0], err, "while caclulating hash");
292		return;
293	}
294	printf("Hash of %s is 0x%0x (minor 0x%0x)\n", argv[optind],
295	       hash, minor_hash);
296}
297
298/*
299 * Search for particular directory entry (useful for debugging very
300 * large hash tree directories that have lost some blocks from the
301 * btree index).
302 */
303struct process_block_struct {
304	char	*search_name;
305	char	*buf;
306	int	len;
307};
308
309static int search_dir_block(ext2_filsys fs, blk_t *blocknr,
310			    e2_blkcnt_t blockcnt, blk_t ref_blk,
311			    int ref_offset, void *priv_data);
312
313void do_dirsearch(int argc, char *argv[])
314{
315	ext2_ino_t	inode;
316	int		retval;
317	int		c;
318	int		flags;
319	struct process_block_struct pb;
320
321	if (check_fs_open(argv[0]))
322		return;
323
324	if (argc != 3) {
325		com_err(0, 0, "Usage: dirsearch dir filename");
326		return;
327	}
328
329	inode = string_to_inode(argv[1]);
330	if (!inode)
331		return;
332
333	pb.buf = malloc(current_fs->blocksize);
334	if (!pb.buf) {
335		com_err("dirsearch", 0, "Couldn't allocate buffer");
336		return;
337	}
338	pb.search_name = argv[2];
339	pb.len = strlen(pb.search_name);
340
341	ext2fs_block_iterate2(current_fs, inode, 0, 0, search_dir_block, &pb);
342
343	free(pb.buf);
344}
345
346
347static int search_dir_block(ext2_filsys fs, blk_t *blocknr,
348			    e2_blkcnt_t blockcnt, blk_t ref_blk,
349			    int ref_offset, void *priv_data)
350{
351	struct process_block_struct *p;
352	struct ext2_dir_entry *dirent;
353	errcode_t	       	errcode;
354	int			offset = 0;
355
356	if (blockcnt < 0)
357		return 0;
358
359	p = (struct process_block_struct *) priv_data;
360
361	errcode = io_channel_read_blk(current_fs->io, *blocknr, 1, p->buf);
362	if (errcode) {
363		com_err("search_dir_block", errcode,
364			"while reading block %lu", *blocknr);
365		return BLOCK_ABORT;
366	}
367
368	while (offset < fs->blocksize) {
369		dirent = (struct ext2_dir_entry *) (p->buf + offset);
370
371		if (dirent->inode &&
372		    p->len == (dirent->name_len & 0xFF) &&
373		    strncmp(p->search_name, dirent->name,
374			    p->len) == 0) {
375			printf("Entry found at logical block %lld, "
376			       "phys %d, offset %d\n", blockcnt,
377			       *blocknr, offset);
378			printf("offset %d\n", offset);
379			return BLOCK_ABORT;
380		}
381		offset += dirent->rec_len;
382	}
383	return 0;
384}
385
386