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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 
27 static FILE *pager;
28 
htree_dump_leaf_node(ext2_filsys fs,ext2_ino_t ino,struct ext2_inode * inode,struct ext2_dx_root_info * rootnode,blk_t blk,char * buf)29 static 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 + 1];
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 
96 static 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 
htree_dump_int_node(ext2_filsys fs,ext2_ino_t ino,struct ext2_inode * inode,struct ext2_dx_root_info * rootnode,struct ext2_dx_entry * ent,char * buf,int level)102 static 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 
htree_dump_int_block(ext2_filsys fs,ext2_ino_t ino,struct ext2_inode * inode,struct ext2_dx_root_info * rootnode,blk_t blk,char * buf,int level)145 static 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 		goto errout;
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 		goto errout;
172 	}
173 
174 	htree_dump_int_node(fs, ino, inode, rootnode,
175 			    (struct ext2_dx_entry *) (buf+8),
176 			    cbuf, level);
177 errout:
178 	free(cbuf);
179 }
180 
181 
182 
do_htree_dump(int argc,char * argv[])183 void do_htree_dump(int argc, char *argv[])
184 {
185 	ext2_ino_t	ino;
186 	struct ext2_inode inode;
187 	int		c;
188 	int		long_opt = 0;
189 	char		*buf = NULL;
190 	struct 		ext2_dx_root_info  *rootnode;
191 	struct 		ext2_dx_entry *ent;
192 	struct		ext2_dx_countlimit *limit;
193 	errcode_t	errcode;
194 
195 	if (check_fs_open(argv[0]))
196 		return;
197 
198 	pager = open_pager();
199 
200 	reset_getopt();
201 	while ((c = getopt (argc, argv, "l")) != EOF) {
202 		switch (c) {
203 		case 'l':
204 			long_opt++;
205 			break;
206 		default:
207 			goto print_usage;
208 		}
209 	}
210 
211 	if (argc > optind+1) {
212 	print_usage:
213 		com_err(0, 0, "Usage: htree_dump [-l] file");
214 		goto errout;
215 	}
216 
217 	if (argc == optind)
218 		ino = cwd;
219 	else
220 		ino = string_to_inode(argv[optind]);
221 	if (!ino)
222 		goto errout;
223 
224 	if (debugfs_read_inode(ino, &inode, argv[1]))
225 		goto errout;
226 
227 	if (!LINUX_S_ISDIR(inode.i_mode)) {
228 		com_err(argv[0], 0, "Not a directory");
229 		goto errout;
230 	}
231 
232 	if ((inode.i_flags & EXT2_BTREE_FL) == 0) {
233 		com_err(argv[0], 0, "Not a hash-indexed directory");
234 		goto errout;
235 	}
236 
237 	buf = malloc(2*current_fs->blocksize);
238 	if (!buf) {
239 		com_err(argv[0], 0, "Couldn't allocate htree buffer");
240 		goto errout;
241 	}
242 
243 	errcode = io_channel_read_blk(current_fs->io, inode.i_block[0],
244 				      1, buf);
245 	if (errcode) {
246 		com_err(argv[0], errcode, "Error reading root node");
247 		goto errout;
248 	}
249 
250 	rootnode = (struct ext2_dx_root_info *) (buf + 24);
251 
252 	fprintf(pager, "Root node dump:\n");
253 	fprintf(pager, "\t Reserved zero: %u\n", rootnode->reserved_zero);
254 	fprintf(pager, "\t Hash Version: %d\n", rootnode->hash_version);
255 	fprintf(pager, "\t Info length: %d\n", rootnode->info_length);
256 	fprintf(pager, "\t Indirect levels: %d\n", rootnode->indirect_levels);
257 	fprintf(pager, "\t Flags: %d\n", rootnode->unused_flags);
258 
259 	ent = (struct ext2_dx_entry *) (buf + 24 + rootnode->info_length);
260 	limit = (struct ext2_dx_countlimit *) ent;
261 
262 	htree_dump_int_node(current_fs, ino, &inode, rootnode, ent,
263 			    buf + current_fs->blocksize,
264 			    rootnode->indirect_levels);
265 
266 errout:
267 	if (buf)
268 		free(buf);
269 	close_pager(pager);
270 }
271 
272 /*
273  * This function prints the hash of a given file.
274  */
do_dx_hash(int argc,char * argv[])275 void do_dx_hash(int argc, char *argv[])
276 {
277 	ext2_dirhash_t hash, minor_hash;
278 	errcode_t	err;
279 	int		c;
280 	int		hash_version = 0;
281 	__u32		hash_seed[4];
282 
283 	hash_seed[0] = hash_seed[1] = hash_seed[2] = hash_seed[3] = 0;
284 
285 	reset_getopt();
286 	while ((c = getopt (argc, argv, "h:")) != EOF) {
287 		switch (c) {
288 		case 'h':
289 			hash_version = atoi(optarg);
290 			break;
291 		default:
292 			goto print_usage;
293 		}
294 	}
295 	if (optind != argc-1) {
296 	print_usage:
297 		com_err(argv[0], 0, "usage: dx_hash filename");
298 		return;
299 	}
300 	err = ext2fs_dirhash(hash_version, argv[optind], strlen(argv[optind]),
301 			     hash_seed, &hash, &minor_hash);
302 	if (err) {
303 		com_err(argv[0], err, "while caclulating hash");
304 		return;
305 	}
306 	printf("Hash of %s is 0x%0x (minor 0x%0x)\n", argv[optind],
307 	       hash, minor_hash);
308 }
309 
310 /*
311  * Search for particular directory entry (useful for debugging very
312  * large hash tree directories that have lost some blocks from the
313  * btree index).
314  */
315 struct process_block_struct {
316 	char	*search_name;
317 	char	*buf;
318 	int	len;
319 };
320 
321 static int search_dir_block(ext2_filsys fs, blk_t *blocknr,
322 			    e2_blkcnt_t blockcnt, blk_t ref_blk,
323 			    int ref_offset, void *priv_data);
324 
do_dirsearch(int argc,char * argv[])325 void do_dirsearch(int argc, char *argv[])
326 {
327 	ext2_ino_t	inode;
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 
search_dir_block(ext2_filsys fs,blk_t * blocknr,e2_blkcnt_t blockcnt,blk_t ref_blk EXT2FS_ATTR ((unused)),int ref_offset EXT2FS_ATTR ((unused)),void * priv_data)356 static int search_dir_block(ext2_filsys fs, blk_t *blocknr,
357 			    e2_blkcnt_t blockcnt,
358 			    blk_t ref_blk EXT2FS_ATTR((unused)),
359 			    int ref_offset EXT2FS_ATTR((unused)),
360 			    void *priv_data)
361 {
362 	struct process_block_struct *p;
363 	struct ext2_dir_entry *dirent;
364 	errcode_t	       	errcode;
365 	unsigned int		offset = 0;
366 
367 	if (blockcnt < 0)
368 		return 0;
369 
370 	p = (struct process_block_struct *) priv_data;
371 
372 	errcode = io_channel_read_blk(current_fs->io, *blocknr, 1, p->buf);
373 	if (errcode) {
374 		com_err("search_dir_block", errcode,
375 			"while reading block %lu", (unsigned long) *blocknr);
376 		return BLOCK_ABORT;
377 	}
378 
379 	while (offset < fs->blocksize) {
380 		dirent = (struct ext2_dir_entry *) (p->buf + offset);
381 
382 		if (dirent->inode &&
383 		    p->len == (dirent->name_len & 0xFF) &&
384 		    strncmp(p->search_name, dirent->name,
385 			    p->len) == 0) {
386 			printf("Entry found at logical block %lld, "
387 			       "phys %u, offset %u\n", (long long)blockcnt,
388 			       *blocknr, offset);
389 			printf("offset %u\n", offset);
390 			return BLOCK_ABORT;
391 		}
392 		offset += dirent->rec_len;
393 	}
394 	return 0;
395 }
396 
397