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 
htree_dump_leaf_node(ext2_filsys fs,ext2_ino_t ino,struct ext2_inode * inode,struct ext2_dx_root_info * rootnode,blk64_t blk,char * buf)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 				 blk64_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 + 64];
42 	blk64_t		pblk;
43 	ext2_dirhash_t 	hash, minor_hash;
44 	unsigned int	rec_len;
45 	int		hash_alg;
46 
47 	errcode = ext2fs_bmap2(fs, ino, inode, buf, 0, blk, 0, &pblk);
48 	if (errcode) {
49 		com_err("htree_dump_leaf_node", errcode,
50 			"while mapping logical block %llu\n", blk);
51 		return;
52 	}
53 
54 	fprintf(pager, "Reading directory block %llu, phys %llu\n", blk, pblk);
55 	errcode = ext2fs_read_dir_block2(current_fs, pblk, buf, 0);
56 	if (errcode) {
57 		com_err("htree_dump_leaf_node", errcode,
58 			"while reading block %llu (%llu)\n",
59 			blk, pblk);
60 		return;
61 	}
62 	hash_alg = rootnode->hash_version;
63 	if ((hash_alg <= EXT2_HASH_TEA) &&
64 	    (fs->super->s_flags & EXT2_FLAGS_UNSIGNED_HASH))
65 		hash_alg += 3;
66 
67 	while (offset < fs->blocksize) {
68 		dirent = (struct ext2_dir_entry *) (buf + offset);
69 		errcode = ext2fs_get_rec_len(fs, dirent, &rec_len);
70 		if (errcode) {
71 			com_err("htree_dump_leaf_inode", errcode,
72 				"while getting rec_len for block %lu",
73 				(unsigned long) blk);
74 			return;
75 		}
76 		if (((offset + rec_len) > fs->blocksize) ||
77 		    (rec_len < 8) ||
78 		    ((rec_len % 4) != 0) ||
79 		    ((((unsigned) dirent->name_len & 0xFF)+8) > rec_len)) {
80 			fprintf(pager, "Corrupted directory block (%llu)!\n",
81 				blk);
82 			break;
83 		}
84 		thislen = dirent->name_len & 0xFF;
85 		strncpy(name, dirent->name, thislen);
86 		name[thislen] = '\0';
87 		errcode = ext2fs_dirhash(hash_alg, name,
88 					 thislen, fs->super->s_hash_seed,
89 					 &hash, &minor_hash);
90 		if (errcode)
91 			com_err("htree_dump_leaf_node", errcode,
92 				"while calculating hash");
93 		snprintf(tmp, EXT2_NAME_LEN + 64, "%u 0x%08x-%08x (%d) %s   ",
94 			dirent->inode, hash, minor_hash, rec_len, name);
95 		thislen = strlen(tmp);
96 		if (col + thislen > 80) {
97 			fprintf(pager, "\n");
98 			col = 0;
99 		}
100 		fprintf(pager, "%s", tmp);
101 		col += thislen;
102 		offset += rec_len;
103 	}
104 	fprintf(pager, "\n");
105 }
106 
107 
108 static void htree_dump_int_block(ext2_filsys fs, ext2_ino_t ino,
109 				 struct ext2_inode *inode,
110 				 struct ext2_dx_root_info * rootnode,
111 				 blk64_t blk, char *buf, int level);
112 
113 
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)114 static void htree_dump_int_node(ext2_filsys fs, ext2_ino_t ino,
115 				struct ext2_inode *inode,
116 				struct ext2_dx_root_info * rootnode,
117 				struct ext2_dx_entry *ent,
118 				char *buf, int level)
119 {
120 	struct ext2_dx_countlimit	limit;
121 	struct ext2_dx_entry		e;
122 	int				hash, i;
123 
124 
125 	limit = *((struct ext2_dx_countlimit *) ent);
126 	limit.count = ext2fs_le16_to_cpu(limit.count);
127 	limit.limit = ext2fs_le16_to_cpu(limit.limit);
128 
129 	fprintf(pager, "Number of entries (count): %d\n", limit.count);
130 	fprintf(pager, "Number of entries (limit): %d\n", limit.limit);
131 
132 	for (i=0; i < limit.count; i++) {
133 		hash = i ? ext2fs_le32_to_cpu(ent[i].hash) : 0;
134 		fprintf(pager, "Entry #%d: Hash 0x%08x%s, block %u\n", i,
135 			hash, (hash & 1) ? " (**)" : "",
136 			ext2fs_le32_to_cpu(ent[i].block));
137 		}
138 
139 	fprintf(pager, "\n");
140 
141 	for (i=0; i < limit.count; i++) {
142 		e.hash = ext2fs_le32_to_cpu(ent[i].hash);
143 		e.block = ext2fs_le32_to_cpu(ent[i].block);
144 		fprintf(pager, "Entry #%d: Hash 0x%08x, block %u\n", i,
145 		       i ? e.hash : 0, e.block);
146 		if (level)
147 			htree_dump_int_block(fs, ino, inode, rootnode,
148 					     e.block, buf, level-1);
149 		else
150 			htree_dump_leaf_node(fs, ino, inode, rootnode,
151 					     e.block, buf);
152 	}
153 
154 	fprintf(pager, "---------------------\n");
155 }
156 
htree_dump_int_block(ext2_filsys fs,ext2_ino_t ino,struct ext2_inode * inode,struct ext2_dx_root_info * rootnode,blk64_t blk,char * buf,int level)157 static void htree_dump_int_block(ext2_filsys fs, ext2_ino_t ino,
158 				 struct ext2_inode *inode,
159 				 struct ext2_dx_root_info * rootnode,
160 				 blk64_t blk, char *buf, int level)
161 {
162 	char		*cbuf;
163 	errcode_t	errcode;
164 	blk64_t		pblk;
165 
166 	cbuf = malloc(fs->blocksize);
167 	if (!cbuf) {
168 		fprintf(pager, "Couldn't allocate child block.\n");
169 		return;
170 	}
171 
172 	errcode = ext2fs_bmap2(fs, ino, inode, buf, 0, blk, 0, &pblk);
173 	if (errcode) {
174 		com_err("htree_dump_int_block", errcode,
175 			"while mapping logical block %llu\n", blk);
176 		goto errout;
177 	}
178 
179 	errcode = io_channel_read_blk64(current_fs->io, pblk, 1, buf);
180 	if (errcode) {
181 		com_err("htree_dump_int_block", errcode,
182 			"while 	reading block %llu\n", blk);
183 		goto errout;
184 	}
185 
186 	htree_dump_int_node(fs, ino, inode, rootnode,
187 			    (struct ext2_dx_entry *) (buf+8),
188 			    cbuf, level);
189 errout:
190 	free(cbuf);
191 }
192 
193 
194 
do_htree_dump(int argc,char * argv[])195 void do_htree_dump(int argc, char *argv[])
196 {
197 	ext2_ino_t	ino;
198 	struct ext2_inode inode;
199 	blk64_t		blk;
200 	char		*buf = NULL;
201 	struct 		ext2_dx_root_info  *rootnode;
202 	struct 		ext2_dx_entry *ent;
203 	errcode_t	errcode;
204 
205 	if (check_fs_open(argv[0]))
206 		return;
207 
208 	pager = open_pager();
209 
210 	if (common_inode_args_process(argc, argv, &ino, 0))
211 		goto errout;
212 
213 	if (debugfs_read_inode(ino, &inode, argv[1]))
214 		goto errout;
215 
216 	if (!LINUX_S_ISDIR(inode.i_mode)) {
217 		com_err(argv[0], 0, "Not a directory");
218 		goto errout;
219 	}
220 
221 	if ((inode.i_flags & EXT2_BTREE_FL) == 0) {
222 		com_err(argv[0], 0, "Not a hash-indexed directory");
223 		goto errout;
224 	}
225 
226 	buf = malloc(2*current_fs->blocksize);
227 	if (!buf) {
228 		com_err(argv[0], 0, "Couldn't allocate htree buffer");
229 		goto errout;
230 	}
231 
232 	errcode = ext2fs_bmap2(current_fs, ino, &inode, buf, 0, 0, 0, &blk);
233 	if (errcode) {
234 		com_err("do_htree_block", errcode,
235 			"while mapping logical block 0\n");
236 		goto errout;
237 	}
238 
239 	errcode = io_channel_read_blk64(current_fs->io, blk,
240 					1, buf);
241 	if (errcode) {
242 		com_err(argv[0], errcode, "Error reading root node");
243 		goto errout;
244 	}
245 
246 	rootnode = (struct ext2_dx_root_info *) (buf + 24);
247 
248 	fprintf(pager, "Root node dump:\n");
249 	fprintf(pager, "\t Reserved zero: %u\n", rootnode->reserved_zero);
250 	fprintf(pager, "\t Hash Version: %d\n", rootnode->hash_version);
251 	fprintf(pager, "\t Info length: %d\n", rootnode->info_length);
252 	fprintf(pager, "\t Indirect levels: %d\n", rootnode->indirect_levels);
253 	fprintf(pager, "\t Flags: %d\n", rootnode->unused_flags);
254 
255 	ent = (struct ext2_dx_entry *) (buf + 24 + rootnode->info_length);
256 
257 	htree_dump_int_node(current_fs, ino, &inode, rootnode, ent,
258 			    buf + current_fs->blocksize,
259 			    rootnode->indirect_levels);
260 
261 errout:
262 	free(buf);
263 	close_pager(pager);
264 }
265 
266 /*
267  * This function prints the hash of a given file.
268  */
do_dx_hash(int argc,char * argv[])269 void do_dx_hash(int argc, char *argv[])
270 {
271 	ext2_dirhash_t hash, minor_hash;
272 	errcode_t	err;
273 	int		c;
274 	int		hash_version = 0;
275 	__u32		hash_seed[4];
276 
277 	hash_seed[0] = hash_seed[1] = hash_seed[2] = hash_seed[3] = 0;
278 
279 	reset_getopt();
280 	while ((c = getopt (argc, argv, "h:s:")) != EOF) {
281 		switch (c) {
282 		case 'h':
283 			hash_version = e2p_string2hash(optarg);
284 			if (hash_version < 0)
285 				hash_version = atoi(optarg);
286 			break;
287 		case 's':
288 			if (uuid_parse(optarg, (unsigned char *) hash_seed)) {
289 				fprintf(stderr, "Invalid UUID format: %s\n",
290 					optarg);
291 				return;
292 			}
293 			break;
294 		default:
295 			goto print_usage;
296 		}
297 	}
298 	if (optind != argc-1) {
299 	print_usage:
300 		com_err(argv[0], 0, "usage: dx_hash [-h hash_alg] "
301 			"[-s hash_seed] filename");
302 		return;
303 	}
304 	err = ext2fs_dirhash(hash_version, argv[optind], strlen(argv[optind]),
305 			     hash_seed, &hash, &minor_hash);
306 	if (err) {
307 		com_err(argv[0], err, "while caclulating hash");
308 		return;
309 	}
310 	printf("Hash of %s is 0x%0x (minor 0x%0x)\n", argv[optind],
311 	       hash, minor_hash);
312 }
313 
314 /*
315  * Search for particular directory entry (useful for debugging very
316  * large hash tree directories that have lost some blocks from the
317  * btree index).
318  */
319 struct process_block_struct {
320 	char	*search_name;
321 	char	*buf;
322 	int	len;
323 };
324 
325 static int search_dir_block(ext2_filsys fs, blk64_t *blocknr,
326 			    e2_blkcnt_t blockcnt, blk64_t ref_blk,
327 			    int ref_offset, void *priv_data);
328 
do_dirsearch(int argc,char * argv[])329 void do_dirsearch(int argc, char *argv[])
330 {
331 	ext2_ino_t	inode;
332 	struct process_block_struct pb;
333 
334 	if (check_fs_open(argv[0]))
335 		return;
336 
337 	if (argc != 3) {
338 		com_err(0, 0, "Usage: dirsearch dir filename");
339 		return;
340 	}
341 
342 	inode = string_to_inode(argv[1]);
343 	if (!inode)
344 		return;
345 
346 	pb.buf = malloc(current_fs->blocksize);
347 	if (!pb.buf) {
348 		com_err("dirsearch", 0, "Couldn't allocate buffer");
349 		return;
350 	}
351 	pb.search_name = argv[2];
352 	pb.len = strlen(pb.search_name);
353 
354 	ext2fs_block_iterate3(current_fs, inode, BLOCK_FLAG_READ_ONLY, 0,
355 			      search_dir_block, &pb);
356 
357 	free(pb.buf);
358 }
359 
360 
search_dir_block(ext2_filsys fs,blk64_t * blocknr,e2_blkcnt_t blockcnt,blk64_t ref_blk EXT2FS_ATTR ((unused)),int ref_offset EXT2FS_ATTR ((unused)),void * priv_data)361 static int search_dir_block(ext2_filsys fs, blk64_t *blocknr,
362 			    e2_blkcnt_t blockcnt,
363 			    blk64_t ref_blk EXT2FS_ATTR((unused)),
364 			    int ref_offset EXT2FS_ATTR((unused)),
365 			    void *priv_data)
366 {
367 	struct process_block_struct *p;
368 	struct ext2_dir_entry *dirent;
369 	errcode_t	       	errcode;
370 	unsigned int		offset = 0;
371 	unsigned int		rec_len;
372 
373 	if (blockcnt < 0)
374 		return 0;
375 
376 	p = (struct process_block_struct *) priv_data;
377 
378 	errcode = io_channel_read_blk64(current_fs->io, *blocknr, 1, p->buf);
379 	if (errcode) {
380 		com_err("search_dir_block", errcode,
381 			"while reading block %lu", (unsigned long) *blocknr);
382 		return BLOCK_ABORT;
383 	}
384 
385 	while (offset < fs->blocksize) {
386 		dirent = (struct ext2_dir_entry *) (p->buf + offset);
387 		errcode = ext2fs_get_rec_len(fs, dirent, &rec_len);
388 		if (errcode) {
389 			com_err("htree_dump_leaf_inode", errcode,
390 				"while getting rec_len for block %lu",
391 				(unsigned long) *blocknr);
392 			return BLOCK_ABORT;
393 		}
394 		if (dirent->inode &&
395 		    p->len == (dirent->name_len & 0xFF) &&
396 		    strncmp(p->search_name, dirent->name,
397 			    p->len) == 0) {
398 			printf("Entry found at logical block %lld, "
399 			       "phys %llu, offset %u\n", (long long)blockcnt,
400 			       *blocknr, offset);
401 			printf("offset %u\n", offset);
402 			return BLOCK_ABORT;
403 		}
404 		offset += rec_len;
405 	}
406 	return 0;
407 }
408 
409