1 /*
2  * Copyright (C) 2010 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include "ext4_utils.h"
18 #include "allocate.h"
19 #include "indirect.h"
20 #include "extent.h"
21 #include "sha1.h"
22 
23 #include <sparse/sparse.h>
24 #ifdef REAL_UUID
25 #include <uuid.h>
26 #endif
27 
28 #include <fcntl.h>
29 #include <inttypes.h>
30 #include <sys/stat.h>
31 #include <sys/types.h>
32 #include <stddef.h>
33 #include <string.h>
34 
35 #ifdef USE_MINGW
36 #include <winsock2.h>
37 #else
38 #include <arpa/inet.h>
39 #include <sys/ioctl.h>
40 #endif
41 
42 #if defined(__linux__)
43 #include <linux/fs.h>
44 #elif defined(__APPLE__) && defined(__MACH__)
45 #include <sys/disk.h>
46 #endif
47 
48 int force = 0;
49 struct fs_info info;
50 struct fs_aux_info aux_info;
51 struct sparse_file *ext4_sparse_file;
52 struct block_allocation *base_fs_allocations = NULL;
53 
54 jmp_buf setjmp_env;
55 
56 /* Definition from RFC-4122 */
57 struct uuid {
58     u32 time_low;
59     u16 time_mid;
60     u16 time_hi_and_version;
61     u8 clk_seq_hi_res;
62     u8 clk_seq_low;
63     u16 node0_1;
64     u32 node2_5;
65 };
66 
sha1_hash(const char * namespace,const char * name,unsigned char sha1[SHA1_DIGEST_LENGTH])67 static void sha1_hash(const char *namespace, const char *name,
68     unsigned char sha1[SHA1_DIGEST_LENGTH])
69 {
70     SHA1_CTX ctx;
71     SHA1Init(&ctx);
72     SHA1Update(&ctx, (const u8*)namespace, strlen(namespace));
73     SHA1Update(&ctx, (const u8*)name, strlen(name));
74     SHA1Final(sha1, &ctx);
75 }
76 
generate_sha1_uuid(const char * namespace,const char * name,u8 result[16])77 static void generate_sha1_uuid(const char *namespace, const char *name, u8 result[16])
78 {
79     unsigned char sha1[SHA1_DIGEST_LENGTH];
80     struct uuid *uuid = (struct uuid *)result;
81 
82     sha1_hash(namespace, name, (unsigned char*)sha1);
83     memcpy(uuid, sha1, sizeof(struct uuid));
84 
85     uuid->time_low = ntohl(uuid->time_low);
86     uuid->time_mid = ntohs(uuid->time_mid);
87     uuid->time_hi_and_version = ntohs(uuid->time_hi_and_version);
88     uuid->time_hi_and_version &= 0x0FFF;
89     uuid->time_hi_and_version |= (5 << 12);
90     uuid->clk_seq_hi_res &= ~(1 << 6);
91     uuid->clk_seq_hi_res |= 1 << 7;
92 }
93 
94 /* returns 1 if a is a power of b */
is_power_of(int a,int b)95 static int is_power_of(int a, int b)
96 {
97 	while (a > b) {
98 		if (a % b)
99 			return 0;
100 		a /= b;
101 	}
102 
103 	return (a == b) ? 1 : 0;
104 }
105 
bitmap_get_bit(u8 * bitmap,u32 bit)106 int bitmap_get_bit(u8 *bitmap, u32 bit)
107 {
108 	if (bitmap[bit / 8] & (1 << (bit % 8)))
109 		return 1;
110 
111 	return 0;
112 }
113 
bitmap_clear_bit(u8 * bitmap,u32 bit)114 void bitmap_clear_bit(u8 *bitmap, u32 bit)
115 {
116 	bitmap[bit / 8] &= ~(1 << (bit % 8));
117 
118 	return;
119 }
120 
121 /* Returns 1 if the bg contains a backup superblock.  On filesystems with
122    the sparse_super feature, only block groups 0, 1, and powers of 3, 5,
123    and 7 have backup superblocks.  Otherwise, all block groups have backup
124    superblocks */
ext4_bg_has_super_block(int bg)125 int ext4_bg_has_super_block(int bg)
126 {
127 	/* Without sparse_super, every block group has a superblock */
128 	if (!(info.feat_ro_compat & EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER))
129 		return 1;
130 
131 	if (bg == 0 || bg == 1)
132 		return 1;
133 
134 	if (is_power_of(bg, 3) || is_power_of(bg, 5) || is_power_of(bg, 7))
135 		return 1;
136 
137 	return 0;
138 }
139 
140 /* Function to read the primary superblock */
read_sb(int fd,struct ext4_super_block * sb)141 void read_sb(int fd, struct ext4_super_block *sb)
142 {
143 	off64_t ret;
144 
145 	ret = lseek64(fd, 1024, SEEK_SET);
146 	if (ret < 0)
147 		critical_error_errno("failed to seek to superblock");
148 
149 	ret = read(fd, sb, sizeof(*sb));
150 	if (ret < 0)
151 		critical_error_errno("failed to read superblock");
152 	if (ret != sizeof(*sb))
153 		critical_error("failed to read all of superblock");
154 }
155 
156 /* Function to write a primary or backup superblock at a given offset */
write_sb(int fd,unsigned long long offset,struct ext4_super_block * sb)157 void write_sb(int fd, unsigned long long offset, struct ext4_super_block *sb)
158 {
159 	off64_t ret;
160 
161 	ret = lseek64(fd, offset, SEEK_SET);
162 	if (ret < 0)
163 		critical_error_errno("failed to seek to superblock");
164 
165 	ret = write(fd, sb, sizeof(*sb));
166 	if (ret < 0)
167 		critical_error_errno("failed to write superblock");
168 	if (ret != sizeof(*sb))
169 		critical_error("failed to write all of superblock");
170 }
171 
block_device_write_sb(int fd)172 static void block_device_write_sb(int fd)
173 {
174 	unsigned long long offset;
175 	u32 i;
176 
177 	/* write out the backup superblocks */
178 	for (i = 1; i < aux_info.groups; i++) {
179 		if (ext4_bg_has_super_block(i)) {
180 			offset = info.block_size * (aux_info.first_data_block
181 				+ i * info.blocks_per_group);
182 			write_sb(fd, offset, aux_info.backup_sb[i]);
183 		}
184 	}
185 
186 	/* write out the primary superblock */
187 	write_sb(fd, 1024, aux_info.sb);
188 }
189 
190 /* Write the filesystem image to a file */
write_ext4_image(int fd,int gz,int sparse,int crc)191 void write_ext4_image(int fd, int gz, int sparse, int crc)
192 {
193 	sparse_file_write(ext4_sparse_file, fd, gz, sparse, crc);
194 
195 	if (info.block_device)
196 		block_device_write_sb(fd);
197 }
198 
199 /* Compute the rest of the parameters of the filesystem from the basic info */
ext4_create_fs_aux_info()200 void ext4_create_fs_aux_info()
201 {
202 	aux_info.first_data_block = (info.block_size > 1024) ? 0 : 1;
203 	aux_info.len_blocks = info.len / info.block_size;
204 	aux_info.inode_table_blocks = DIV_ROUND_UP(info.inodes_per_group * info.inode_size,
205 		info.block_size);
206 	aux_info.groups = DIV_ROUND_UP(aux_info.len_blocks - aux_info.first_data_block,
207 		info.blocks_per_group);
208 	aux_info.blocks_per_ind = info.block_size / sizeof(u32);
209 	aux_info.blocks_per_dind = aux_info.blocks_per_ind * aux_info.blocks_per_ind;
210 	aux_info.blocks_per_tind = aux_info.blocks_per_dind * aux_info.blocks_per_dind;
211 
212 	aux_info.bg_desc_blocks =
213 		DIV_ROUND_UP(aux_info.groups * sizeof(struct ext2_group_desc),
214 			info.block_size);
215 
216 	aux_info.default_i_flags = EXT4_NOATIME_FL;
217 
218 	u32 last_group_size = aux_info.len_blocks % info.blocks_per_group;
219 	u32 last_header_size = 2 + aux_info.inode_table_blocks;
220 	if (ext4_bg_has_super_block(aux_info.groups - 1))
221 		last_header_size += 1 + aux_info.bg_desc_blocks +
222 			info.bg_desc_reserve_blocks;
223 	if (last_group_size > 0 && last_group_size < last_header_size) {
224 		aux_info.groups--;
225 		aux_info.len_blocks -= last_group_size;
226 	}
227 
228 	/* A zero-filled superblock to be written firstly to the block
229 	 * device to mark the file-system as invalid
230 	 */
231 	aux_info.sb_zero = calloc(1, info.block_size);
232 	if (!aux_info.sb_zero)
233 		critical_error_errno("calloc");
234 
235 	/* The write_data* functions expect only block aligned calls.
236 	 * This is not an issue, except when we write out the super
237 	 * block on a system with a block size > 1K.  So, we need to
238 	 * deal with that here.
239 	 */
240 	aux_info.sb_block = calloc(1, info.block_size);
241 	if (!aux_info.sb_block)
242 		critical_error_errno("calloc");
243 
244 	if (info.block_size > 1024)
245 		aux_info.sb = (struct ext4_super_block *)((char *)aux_info.sb_block + 1024);
246 	else
247 		aux_info.sb = aux_info.sb_block;
248 
249 	/* Alloc an array to hold the pointers to the backup superblocks */
250 	aux_info.backup_sb = calloc(aux_info.groups, sizeof(char *));
251 
252 	if (!aux_info.sb)
253 		critical_error_errno("calloc");
254 
255 	aux_info.bg_desc = calloc(info.block_size, aux_info.bg_desc_blocks);
256 	if (!aux_info.bg_desc)
257 		critical_error_errno("calloc");
258 	aux_info.xattrs = NULL;
259 }
260 
ext4_free_fs_aux_info()261 void ext4_free_fs_aux_info()
262 {
263 	unsigned int i;
264 
265 	for (i=0; i<aux_info.groups; i++) {
266 		if (aux_info.backup_sb[i])
267 			free(aux_info.backup_sb[i]);
268 	}
269 	free(aux_info.sb_block);
270 	free(aux_info.sb_zero);
271 	free(aux_info.bg_desc);
272 }
273 
274 /* Fill in the superblock memory buffer based on the filesystem parameters */
ext4_fill_in_sb(int real_uuid)275 void ext4_fill_in_sb(int real_uuid)
276 {
277 	unsigned int i;
278 	struct ext4_super_block *sb = aux_info.sb;
279 
280 	sb->s_inodes_count = info.inodes_per_group * aux_info.groups;
281 	sb->s_blocks_count_lo = aux_info.len_blocks;
282 	sb->s_r_blocks_count_lo = 0;
283 	sb->s_free_blocks_count_lo = 0;
284 	sb->s_free_inodes_count = 0;
285 	sb->s_first_data_block = aux_info.first_data_block;
286 	sb->s_log_block_size = log_2(info.block_size / 1024);
287 	sb->s_obso_log_frag_size = log_2(info.block_size / 1024);
288 	sb->s_blocks_per_group = info.blocks_per_group;
289 	sb->s_obso_frags_per_group = info.blocks_per_group;
290 	sb->s_inodes_per_group = info.inodes_per_group;
291 	sb->s_mtime = 0;
292 	sb->s_wtime = 0;
293 	sb->s_mnt_count = 0;
294 	sb->s_max_mnt_count = 10;
295 	sb->s_magic = EXT4_SUPER_MAGIC;
296 	sb->s_state = EXT4_VALID_FS;
297 	sb->s_errors = EXT4_ERRORS_RO;
298 	sb->s_minor_rev_level = 0;
299 	sb->s_lastcheck = 0;
300 	sb->s_checkinterval = 0;
301 	sb->s_creator_os = EXT4_OS_LINUX;
302 	sb->s_rev_level = EXT4_DYNAMIC_REV;
303 	sb->s_def_resuid = EXT4_DEF_RESUID;
304 	sb->s_def_resgid = EXT4_DEF_RESGID;
305 
306 	sb->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
307 	sb->s_inode_size = info.inode_size;
308 	sb->s_block_group_nr = 0;
309 	sb->s_feature_compat = info.feat_compat;
310 	sb->s_feature_incompat = info.feat_incompat;
311 	sb->s_feature_ro_compat = info.feat_ro_compat;
312 	if (real_uuid == 1) {
313 #ifdef REAL_UUID
314 	    uuid_generate(sb->s_uuid);
315 #else
316 	    fprintf(stderr, "Not compiled with real UUID support\n");
317 	    abort();
318 #endif
319 	} else {
320 	    generate_sha1_uuid("extandroid/make_ext4fs", info.label, sb->s_uuid);
321 	}
322 	memset(sb->s_volume_name, 0, sizeof(sb->s_volume_name));
323 	strncpy(sb->s_volume_name, info.label, sizeof(sb->s_volume_name));
324 	memset(sb->s_last_mounted, 0, sizeof(sb->s_last_mounted));
325 	sb->s_algorithm_usage_bitmap = 0;
326 
327 	sb->s_reserved_gdt_blocks = info.bg_desc_reserve_blocks;
328 	sb->s_prealloc_blocks = 0;
329 	sb->s_prealloc_dir_blocks = 0;
330 
331 	//memcpy(sb->s_journal_uuid, sb->s_uuid, sizeof(sb->s_journal_uuid));
332 	if (info.feat_compat & EXT4_FEATURE_COMPAT_HAS_JOURNAL)
333 		sb->s_journal_inum = EXT4_JOURNAL_INO;
334 	sb->s_journal_dev = 0;
335 	sb->s_last_orphan = 0;
336 	sb->s_hash_seed[0] = 0; /* FIXME */
337 	sb->s_def_hash_version = DX_HASH_TEA;
338 	sb->s_reserved_char_pad = EXT4_JNL_BACKUP_BLOCKS;
339 	sb->s_desc_size = sizeof(struct ext2_group_desc);
340 	sb->s_default_mount_opts = 0; /* FIXME */
341 	sb->s_first_meta_bg = 0;
342 	sb->s_mkfs_time = 0;
343 	//sb->s_jnl_blocks[17]; /* FIXME */
344 
345 	sb->s_blocks_count_hi = aux_info.len_blocks >> 32;
346 	sb->s_r_blocks_count_hi = 0;
347 	sb->s_free_blocks_count_hi = 0;
348 	sb->s_min_extra_isize = sizeof(struct ext4_inode) -
349 		EXT4_GOOD_OLD_INODE_SIZE;
350 	sb->s_want_extra_isize = sizeof(struct ext4_inode) -
351 		EXT4_GOOD_OLD_INODE_SIZE;
352 	sb->s_flags = 2;
353 	sb->s_raid_stride = 0;
354 	sb->s_mmp_interval = 0;
355 	sb->s_mmp_block = 0;
356 	sb->s_raid_stripe_width = 0;
357 	sb->s_log_groups_per_flex = 0;
358 	sb->s_kbytes_written = 0;
359 
360 	for (i = 0; i < aux_info.groups; i++) {
361 		u64 group_start_block = aux_info.first_data_block + i *
362 			info.blocks_per_group;
363 		u32 header_size = 0;
364 		if (ext4_bg_has_super_block(i)) {
365 			if (i != 0) {
366 				aux_info.backup_sb[i] = calloc(info.block_size, 1);
367 				memcpy(aux_info.backup_sb[i], sb, sizeof(struct ext4_super_block));
368 				/* Update the block group nr of this backup superblock */
369 				aux_info.backup_sb[i]->s_block_group_nr = i;
370 				ext4_queue_sb(group_start_block, info.block_device ?
371 						aux_info.sb_zero : aux_info.backup_sb[i]);
372 			}
373 			sparse_file_add_data(ext4_sparse_file, aux_info.bg_desc,
374 				aux_info.bg_desc_blocks * info.block_size,
375 				group_start_block + 1);
376 			header_size = 1 + aux_info.bg_desc_blocks + info.bg_desc_reserve_blocks;
377 		}
378 
379 		aux_info.bg_desc[i].bg_block_bitmap = group_start_block + header_size;
380 		aux_info.bg_desc[i].bg_inode_bitmap = group_start_block + header_size + 1;
381 		aux_info.bg_desc[i].bg_inode_table = group_start_block + header_size + 2;
382 
383 		aux_info.bg_desc[i].bg_free_blocks_count = sb->s_blocks_per_group;
384 		aux_info.bg_desc[i].bg_free_inodes_count = sb->s_inodes_per_group;
385 		aux_info.bg_desc[i].bg_used_dirs_count = 0;
386 	}
387 
388 	/* Queue the primary superblock to be written out - if it's a block device,
389 	 * queue a zero-filled block first, the correct version of superblock will
390 	 * be written to the block device after all other blocks are written.
391 	 *
392 	 * The file-system on the block device will not be valid until the correct
393 	 * version of superblocks are written, this is to avoid the likelihood of a
394 	 * partially created file-system.
395 	 */
396 	ext4_queue_sb(aux_info.first_data_block, info.block_device ?
397 				aux_info.sb_zero : aux_info.sb_block);
398 }
399 
400 
ext4_queue_sb(u64 start_block,struct ext4_super_block * sb)401 void ext4_queue_sb(u64 start_block, struct ext4_super_block *sb)
402 {
403 	sparse_file_add_data(ext4_sparse_file, sb, info.block_size, start_block);
404 }
405 
ext4_parse_sb_info(struct ext4_super_block * sb)406 void ext4_parse_sb_info(struct ext4_super_block *sb)
407 {
408 	if (sb->s_magic != EXT4_SUPER_MAGIC)
409 		error("superblock magic incorrect");
410 
411 	if ((sb->s_state & EXT4_VALID_FS) != EXT4_VALID_FS)
412 		error("filesystem state not valid");
413 
414 	ext4_parse_sb(sb, &info);
415 
416 	ext4_create_fs_aux_info();
417 
418 	memcpy(aux_info.sb, sb, sizeof(*sb));
419 
420 	if (aux_info.first_data_block != sb->s_first_data_block)
421 		critical_error("first data block does not match");
422 }
423 
ext4_create_resize_inode()424 void ext4_create_resize_inode()
425 {
426 	struct block_allocation *reserve_inode_alloc = create_allocation();
427 	u32 reserve_inode_len = 0;
428 	unsigned int i;
429 
430 	struct ext4_inode *inode = get_inode(EXT4_RESIZE_INO);
431 	if (inode == NULL) {
432 		error("failed to get resize inode");
433 		return;
434 	}
435 
436 	for (i = 0; i < aux_info.groups; i++) {
437 		if (ext4_bg_has_super_block(i)) {
438 			u64 group_start_block = aux_info.first_data_block + i *
439 				info.blocks_per_group;
440 			u32 reserved_block_start = group_start_block + 1 +
441 				aux_info.bg_desc_blocks;
442 			u32 reserved_block_len = info.bg_desc_reserve_blocks;
443 			append_region(reserve_inode_alloc, reserved_block_start,
444 				reserved_block_len, i);
445 			reserve_inode_len += reserved_block_len;
446 		}
447 	}
448 
449 	inode_attach_resize(inode, reserve_inode_alloc);
450 
451 	inode->i_mode = S_IFREG | S_IRUSR | S_IWUSR;
452 	inode->i_links_count = 1;
453 
454 	free_alloc(reserve_inode_alloc);
455 }
456 
457 /* Allocate the blocks to hold a journal inode and connect them to the
458    reserved journal inode */
ext4_create_journal_inode()459 void ext4_create_journal_inode()
460 {
461 	struct ext4_inode *inode = get_inode(EXT4_JOURNAL_INO);
462 	if (inode == NULL) {
463 		error("failed to get journal inode");
464 		return;
465 	}
466 
467 	u8 *journal_data = inode_allocate_data_extents(inode,
468 			info.journal_blocks * info.block_size,
469 			info.journal_blocks * info.block_size);
470 	if (!journal_data) {
471 		error("failed to allocate extents for journal data");
472 		return;
473 	}
474 
475 	inode->i_mode = S_IFREG | S_IRUSR | S_IWUSR;
476 	inode->i_links_count = 1;
477 
478 	journal_superblock_t *jsb = (journal_superblock_t *)journal_data;
479 	jsb->s_header.h_magic = htonl(JBD2_MAGIC_NUMBER);
480 	jsb->s_header.h_blocktype = htonl(JBD2_SUPERBLOCK_V2);
481 	jsb->s_blocksize = htonl(info.block_size);
482 	jsb->s_maxlen = htonl(info.journal_blocks);
483 	jsb->s_nr_users = htonl(1);
484 	jsb->s_first = htonl(1);
485 	jsb->s_sequence = htonl(1);
486 
487 	memcpy(aux_info.sb->s_jnl_blocks, &inode->i_block, sizeof(inode->i_block));
488 }
489 
490 /* Update the number of free blocks and inodes in the filesystem and in each
491    block group */
ext4_update_free()492 void ext4_update_free()
493 {
494 	u32 i;
495 
496 	for (i = 0; i < aux_info.groups; i++) {
497 		u32 bg_free_blocks = get_free_blocks(i);
498 		u32 bg_free_inodes = get_free_inodes(i);
499 		u16 crc;
500 
501 		aux_info.bg_desc[i].bg_free_blocks_count = bg_free_blocks;
502 		aux_info.sb->s_free_blocks_count_lo += bg_free_blocks;
503 
504 		aux_info.bg_desc[i].bg_free_inodes_count = bg_free_inodes;
505 		aux_info.sb->s_free_inodes_count += bg_free_inodes;
506 
507 		aux_info.bg_desc[i].bg_used_dirs_count += get_directories(i);
508 
509 		aux_info.bg_desc[i].bg_flags = get_bg_flags(i);
510 
511 		crc = ext4_crc16(~0, aux_info.sb->s_uuid, sizeof(aux_info.sb->s_uuid));
512 		crc = ext4_crc16(crc, &i, sizeof(i));
513 		crc = ext4_crc16(crc, &aux_info.bg_desc[i], offsetof(struct ext2_group_desc, bg_checksum));
514 		aux_info.bg_desc[i].bg_checksum = crc;
515 	}
516 }
517 
get_block_device_size(int fd)518 u64 get_block_device_size(int fd)
519 {
520 	u64 size = 0;
521 	int ret;
522 
523 #if defined(__linux__)
524 	ret = ioctl(fd, BLKGETSIZE64, &size);
525 #elif defined(__APPLE__) && defined(__MACH__)
526 	ret = ioctl(fd, DKIOCGETBLOCKCOUNT, &size);
527 #else
528 	close(fd);
529 	return 0;
530 #endif
531 
532 	if (ret)
533 		return 0;
534 
535 	return size;
536 }
537 
is_block_device_fd(int fd)538 int is_block_device_fd(int fd)
539 {
540 #ifdef USE_MINGW
541 	return 0;
542 #else
543 	struct stat st;
544 	int ret = fstat(fd, &st);
545 	if (ret < 0)
546 		return 0;
547 
548 	return S_ISBLK(st.st_mode);
549 #endif
550 }
551 
get_file_size(int fd)552 u64 get_file_size(int fd)
553 {
554 	struct stat buf;
555 	int ret;
556 	u64 reserve_len = 0;
557 	s64 computed_size;
558 
559 	ret = fstat(fd, &buf);
560 	if (ret)
561 		return 0;
562 
563 	if (info.len < 0)
564 		reserve_len = -info.len;
565 
566 	if (S_ISREG(buf.st_mode))
567 		computed_size = buf.st_size - reserve_len;
568 	else if (S_ISBLK(buf.st_mode))
569 		computed_size = get_block_device_size(fd) - reserve_len;
570 	else
571 		computed_size = 0;
572 
573 	if (computed_size < 0) {
574 		warn("Computed filesystem size less than 0");
575 		computed_size = 0;
576 	}
577 
578 	return computed_size;
579 }
580 
parse_num(const char * arg)581 u64 parse_num(const char *arg)
582 {
583 	char *endptr;
584 	u64 num = strtoull(arg, &endptr, 10);
585 	if (*endptr == 'k' || *endptr == 'K')
586 		num *= 1024LL;
587 	else if (*endptr == 'm' || *endptr == 'M')
588 		num *= 1024LL * 1024LL;
589 	else if (*endptr == 'g' || *endptr == 'G')
590 		num *= 1024LL * 1024LL * 1024LL;
591 
592 	return num;
593 }
594 
read_ext(int fd,int verbose)595 int read_ext(int fd, int verbose)
596 {
597 	off64_t ret;
598 	struct ext4_super_block sb;
599 
600 	read_sb(fd, &sb);
601 
602 	ext4_parse_sb_info(&sb);
603 
604 	ret = lseek64(fd, info.len, SEEK_SET);
605 	if (ret < 0)
606 		critical_error_errno("failed to seek to end of input image");
607 
608 	ret = lseek64(fd, info.block_size * (aux_info.first_data_block + 1), SEEK_SET);
609 	if (ret < 0)
610 		critical_error_errno("failed to seek to block group descriptors");
611 
612 	ret = read(fd, aux_info.bg_desc, info.block_size * aux_info.bg_desc_blocks);
613 	if (ret < 0)
614 		critical_error_errno("failed to read block group descriptors");
615 	if (ret != (int)info.block_size * (int)aux_info.bg_desc_blocks)
616 		critical_error("failed to read all of block group descriptors");
617 
618 	if (verbose) {
619 		printf("Found filesystem with parameters:\n");
620 		printf("    Size: %"PRIu64"\n", info.len);
621 		printf("    Block size: %d\n", info.block_size);
622 		printf("    Blocks per group: %d\n", info.blocks_per_group);
623 		printf("    Inodes per group: %d\n", info.inodes_per_group);
624 		printf("    Inode size: %d\n", info.inode_size);
625 		printf("    Label: %s\n", info.label);
626 		printf("    Blocks: %"PRIu64"\n", aux_info.len_blocks);
627 		printf("    Block groups: %d\n", aux_info.groups);
628 		printf("    Reserved block group size: %d\n", info.bg_desc_reserve_blocks);
629 		printf("    Used %d/%d inodes and %d/%d blocks\n",
630 			aux_info.sb->s_inodes_count - aux_info.sb->s_free_inodes_count,
631 			aux_info.sb->s_inodes_count,
632 			aux_info.sb->s_blocks_count_lo - aux_info.sb->s_free_blocks_count_lo,
633 			aux_info.sb->s_blocks_count_lo);
634 	}
635 
636 	return 0;
637 }
638 
639