2 * swapfs.c --- swap ext2 filesystem data structures
4 * Copyright (C) 1995, 1996, 2002 Theodore Ts'o.
7 * This file may be redistributed under the terms of the GNU Library
8 * General Public License, version 2.
23 #include <ext2fs/ext2_ext_attr.h>
25 #ifdef WORDS_BIGENDIAN
26 void ext2fs_swap_super(struct ext2_super_block * sb)
30 sb->s_inodes_count = ext2fs_swab32(sb->s_inodes_count);
31 sb->s_blocks_count = ext2fs_swab32(sb->s_blocks_count);
32 sb->s_r_blocks_count = ext2fs_swab32(sb->s_r_blocks_count);
33 sb->s_free_blocks_count = ext2fs_swab32(sb->s_free_blocks_count);
34 sb->s_free_inodes_count = ext2fs_swab32(sb->s_free_inodes_count);
35 sb->s_first_data_block = ext2fs_swab32(sb->s_first_data_block);
36 sb->s_log_block_size = ext2fs_swab32(sb->s_log_block_size);
37 sb->s_log_cluster_size = ext2fs_swab32(sb->s_log_cluster_size);
38 sb->s_blocks_per_group = ext2fs_swab32(sb->s_blocks_per_group);
39 sb->s_clusters_per_group = ext2fs_swab32(sb->s_clusters_per_group);
40 sb->s_inodes_per_group = ext2fs_swab32(sb->s_inodes_per_group);
41 sb->s_mtime = ext2fs_swab32(sb->s_mtime);
42 sb->s_wtime = ext2fs_swab32(sb->s_wtime);
43 sb->s_mnt_count = ext2fs_swab16(sb->s_mnt_count);
44 sb->s_max_mnt_count = ext2fs_swab16(sb->s_max_mnt_count);
45 sb->s_magic = ext2fs_swab16(sb->s_magic);
46 sb->s_state = ext2fs_swab16(sb->s_state);
47 sb->s_errors = ext2fs_swab16(sb->s_errors);
48 sb->s_minor_rev_level = ext2fs_swab16(sb->s_minor_rev_level);
49 sb->s_lastcheck = ext2fs_swab32(sb->s_lastcheck);
50 sb->s_checkinterval = ext2fs_swab32(sb->s_checkinterval);
51 sb->s_creator_os = ext2fs_swab32(sb->s_creator_os);
52 sb->s_rev_level = ext2fs_swab32(sb->s_rev_level);
53 sb->s_def_resuid = ext2fs_swab16(sb->s_def_resuid);
54 sb->s_def_resgid = ext2fs_swab16(sb->s_def_resgid);
55 sb->s_first_ino = ext2fs_swab32(sb->s_first_ino);
56 sb->s_inode_size = ext2fs_swab16(sb->s_inode_size);
57 sb->s_block_group_nr = ext2fs_swab16(sb->s_block_group_nr);
58 sb->s_feature_compat = ext2fs_swab32(sb->s_feature_compat);
59 sb->s_feature_incompat = ext2fs_swab32(sb->s_feature_incompat);
60 sb->s_feature_ro_compat = ext2fs_swab32(sb->s_feature_ro_compat);
61 /* sb->s_uuid is __u8 and does not need swabbing */
62 /* sb->s_volume_name is char and does not need swabbing */
63 /* sb->s_last_mounted is char and does not need swabbing */
64 sb->s_algorithm_usage_bitmap = ext2fs_swab32(sb->s_algorithm_usage_bitmap);
65 /* sb->s_prealloc_blocks is __u8 and does not need swabbing */
66 /* sb->s_prealloc_dir_blocks is __u8 and does not need swabbing */
67 sb->s_reserved_gdt_blocks = ext2fs_swab16(sb->s_reserved_gdt_blocks);
68 /* sb->s_journal_uuid is __u8 and does not need swabbing */
69 sb->s_journal_inum = ext2fs_swab32(sb->s_journal_inum);
70 sb->s_journal_dev = ext2fs_swab32(sb->s_journal_dev);
71 sb->s_last_orphan = ext2fs_swab32(sb->s_last_orphan);
72 for (i = 0; i < 4; i++)
73 sb->s_hash_seed[i] = ext2fs_swab32(sb->s_hash_seed[i]);
74 /* sb->s_def_hash_version is __u8 and does not need swabbing */
75 /* sb->s_jnl_backup_type is __u8 and does not need swabbing */
76 sb->s_desc_size = ext2fs_swab16(sb->s_desc_size);
77 sb->s_default_mount_opts = ext2fs_swab32(sb->s_default_mount_opts);
78 sb->s_first_meta_bg = ext2fs_swab32(sb->s_first_meta_bg);
79 sb->s_mkfs_time = ext2fs_swab32(sb->s_mkfs_time);
80 /* if journal backup is for a valid extent-based journal... */
81 if (ext2fs_extent_header_verify(sb->s_jnl_blocks,
82 sizeof(sb->s_jnl_blocks)) == 0) {
83 /* ... swap only the journal i_size and i_size_high,
84 * and the extent data is not swapped on read */
87 /* direct/indirect journal: swap it all */
91 sb->s_jnl_blocks[i] = ext2fs_swab32(sb->s_jnl_blocks[i]);
92 sb->s_blocks_count_hi = ext2fs_swab32(sb->s_blocks_count_hi);
93 sb->s_r_blocks_count_hi = ext2fs_swab32(sb->s_r_blocks_count_hi);
94 sb->s_free_blocks_hi = ext2fs_swab32(sb->s_free_blocks_hi);
95 sb->s_min_extra_isize = ext2fs_swab16(sb->s_min_extra_isize);
96 sb->s_want_extra_isize = ext2fs_swab16(sb->s_want_extra_isize);
97 sb->s_flags = ext2fs_swab32(sb->s_flags);
98 sb->s_raid_stride = ext2fs_swab16(sb->s_raid_stride);
99 sb->s_mmp_update_interval = ext2fs_swab16(sb->s_mmp_update_interval);
100 sb->s_mmp_block = ext2fs_swab64(sb->s_mmp_block);
101 sb->s_raid_stripe_width = ext2fs_swab32(sb->s_raid_stripe_width);
102 /* sb->s_log_groups_per_flex is __u8 and does not need swabbing */
103 /* sb->s_checksum_type is __u8 and does not need swabbing */
104 /* sb->s_encryption_level is __u8 and does not need swabbing */
105 /* sb->s_reserved_pad is __u8 and does not need swabbing */
106 sb->s_kbytes_written = ext2fs_swab64(sb->s_kbytes_written);
107 sb->s_snapshot_inum = ext2fs_swab32(sb->s_snapshot_inum);
108 sb->s_snapshot_id = ext2fs_swab32(sb->s_snapshot_id);
109 sb->s_snapshot_r_blocks_count =
110 ext2fs_swab64(sb->s_snapshot_r_blocks_count);
111 sb->s_snapshot_list = ext2fs_swab32(sb->s_snapshot_list);
112 sb->s_error_count = ext2fs_swab32(sb->s_error_count);
113 sb->s_first_error_time = ext2fs_swab32(sb->s_first_error_time);
114 sb->s_first_error_ino = ext2fs_swab32(sb->s_first_error_ino);
115 sb->s_first_error_block = ext2fs_swab64(sb->s_first_error_block);
116 /* sb->s_first_error_func is __u8 and does not need swabbing */
117 sb->s_last_error_time = ext2fs_swab32(sb->s_last_error_time);
118 sb->s_last_error_ino = ext2fs_swab32(sb->s_last_error_ino);
119 sb->s_last_error_block = ext2fs_swab64(sb->s_last_error_block);
120 /* sb->s_last_error_func is __u8 and does not need swabbing */
121 /* sb->s_mount_opts is __u8 and does not need swabbing */
122 sb->s_usr_quota_inum = ext2fs_swab32(sb->s_usr_quota_inum);
123 sb->s_grp_quota_inum = ext2fs_swab32(sb->s_grp_quota_inum);
124 sb->s_overhead_blocks = ext2fs_swab32(sb->s_overhead_blocks);
125 sb->s_backup_bgs[0] = ext2fs_swab32(sb->s_backup_bgs[0]);
126 sb->s_backup_bgs[1] = ext2fs_swab32(sb->s_backup_bgs[1]);
127 /* sb->s_encrypt_algos is __u8 and does not need swabbing */
128 /* sb->s_encrypt_pw_salt is __u8 and does not need swabbing */
129 sb->s_lpf_ino = ext2fs_swab32(sb->s_lpf_ino);
130 sb->s_prj_quota_inum = ext2fs_swab32(sb->s_prj_quota_inum);
131 sb->s_checksum_seed = ext2fs_swab32(sb->s_checksum_seed);
132 /* catch when new fields are used from s_reserved */
133 EXT2FS_BUILD_BUG_ON(sizeof(sb->s_reserved) != 98 * sizeof(__le32));
134 sb->s_checksum = ext2fs_swab32(sb->s_checksum);
137 void ext2fs_swap_group_desc2(ext2_filsys fs, struct ext2_group_desc *gdp)
139 struct ext4_group_desc *gdp4 = (struct ext4_group_desc *)gdp;
141 /* Do the 32-bit parts first */
142 gdp->bg_block_bitmap = ext2fs_swab32(gdp->bg_block_bitmap);
143 gdp->bg_inode_bitmap = ext2fs_swab32(gdp->bg_inode_bitmap);
144 gdp->bg_inode_table = ext2fs_swab32(gdp->bg_inode_table);
145 gdp->bg_free_blocks_count = ext2fs_swab16(gdp->bg_free_blocks_count);
146 gdp->bg_free_inodes_count = ext2fs_swab16(gdp->bg_free_inodes_count);
147 gdp->bg_used_dirs_count = ext2fs_swab16(gdp->bg_used_dirs_count);
148 gdp->bg_flags = ext2fs_swab16(gdp->bg_flags);
149 gdp->bg_exclude_bitmap_lo = ext2fs_swab32(gdp->bg_exclude_bitmap_lo);
150 gdp->bg_block_bitmap_csum_lo =
151 ext2fs_swab16(gdp->bg_block_bitmap_csum_lo);
152 gdp->bg_inode_bitmap_csum_lo =
153 ext2fs_swab16(gdp->bg_inode_bitmap_csum_lo);
154 gdp->bg_itable_unused = ext2fs_swab16(gdp->bg_itable_unused);
155 gdp->bg_checksum = ext2fs_swab16(gdp->bg_checksum);
156 /* If we're 32-bit, we're done */
157 if (fs == NULL || EXT2_DESC_SIZE(fs->super) < EXT2_MIN_DESC_SIZE_64BIT)
160 /* Swap the 64-bit parts */
161 gdp4->bg_block_bitmap_hi = ext2fs_swab32(gdp4->bg_block_bitmap_hi);
162 gdp4->bg_inode_bitmap_hi = ext2fs_swab32(gdp4->bg_inode_bitmap_hi);
163 gdp4->bg_inode_table_hi = ext2fs_swab32(gdp4->bg_inode_table_hi);
164 gdp4->bg_free_blocks_count_hi =
165 ext2fs_swab16(gdp4->bg_free_blocks_count_hi);
166 gdp4->bg_free_inodes_count_hi =
167 ext2fs_swab16(gdp4->bg_free_inodes_count_hi);
168 gdp4->bg_used_dirs_count_hi =
169 ext2fs_swab16(gdp4->bg_used_dirs_count_hi);
170 gdp4->bg_itable_unused_hi = ext2fs_swab16(gdp4->bg_itable_unused_hi);
171 gdp4->bg_exclude_bitmap_hi = ext2fs_swab16(gdp4->bg_exclude_bitmap_hi);
172 gdp4->bg_block_bitmap_csum_hi =
173 ext2fs_swab16(gdp4->bg_block_bitmap_csum_hi);
174 gdp4->bg_inode_bitmap_csum_hi =
175 ext2fs_swab16(gdp4->bg_inode_bitmap_csum_hi);
176 EXT2FS_BUILD_BUG_ON(sizeof(gdp4->bg_reserved) != sizeof(__u32));
179 void ext2fs_swap_group_desc(struct ext2_group_desc *gdp)
181 ext2fs_swap_group_desc2(0, gdp);
185 void ext2fs_swap_ext_attr_header(struct ext2_ext_attr_header *to_header,
186 struct ext2_ext_attr_header *from_header)
190 to_header->h_magic = ext2fs_swab32(from_header->h_magic);
191 to_header->h_blocks = ext2fs_swab32(from_header->h_blocks);
192 to_header->h_refcount = ext2fs_swab32(from_header->h_refcount);
193 to_header->h_hash = ext2fs_swab32(from_header->h_hash);
194 to_header->h_checksum = ext2fs_swab32(from_header->h_checksum);
195 for (n = 0; n < 3; n++)
196 to_header->h_reserved[n] =
197 ext2fs_swab32(from_header->h_reserved[n]);
200 void ext2fs_swap_ext_attr_entry(struct ext2_ext_attr_entry *to_entry,
201 struct ext2_ext_attr_entry *from_entry)
203 to_entry->e_value_offs = ext2fs_swab16(from_entry->e_value_offs);
204 to_entry->e_value_inum = ext2fs_swab32(from_entry->e_value_inum);
205 to_entry->e_value_size = ext2fs_swab32(from_entry->e_value_size);
206 to_entry->e_hash = ext2fs_swab32(from_entry->e_hash);
209 void ext2fs_swap_ext_attr(char *to, char *from, int bufsize, int has_header)
211 struct ext2_ext_attr_header *from_header =
212 (struct ext2_ext_attr_header *)from;
213 struct ext2_ext_attr_header *to_header =
214 (struct ext2_ext_attr_header *)to;
215 struct ext2_ext_attr_entry *from_entry, *to_entry;
216 char *from_end = (char *)from_header + bufsize;
218 if (to_header != from_header)
219 memcpy(to_header, from_header, bufsize);
222 ext2fs_swap_ext_attr_header(to_header, from_header);
224 from_entry = (struct ext2_ext_attr_entry *)(from_header+1);
225 to_entry = (struct ext2_ext_attr_entry *)(to_header+1);
227 from_entry = (struct ext2_ext_attr_entry *)from_header;
228 to_entry = (struct ext2_ext_attr_entry *)to_header;
231 while ((char *)from_entry < from_end &&
232 (char *)EXT2_EXT_ATTR_NEXT(from_entry) <= from_end &&
233 *(__u32 *)from_entry) {
234 ext2fs_swap_ext_attr_entry(to_entry, from_entry);
235 from_entry = EXT2_EXT_ATTR_NEXT(from_entry);
236 to_entry = EXT2_EXT_ATTR_NEXT(to_entry);
240 void ext2fs_swap_inode_full(ext2_filsys fs, struct ext2_inode_large *t,
241 struct ext2_inode_large *f, int hostorder,
244 unsigned i, extra_isize, attr_magic;
245 int has_extents, has_inline_data, islnk, fast_symlink;
250 * Note that t and f may point to the same address. That's why
251 * if (hostorder) condition is executed before swab calls and
252 * if (!hostorder) afterwards.
255 islnk = LINUX_S_ISLNK(f->i_mode);
256 fast_symlink = ext2fs_is_fast_symlink(EXT2_INODE(f));
257 has_extents = (f->i_flags & EXT4_EXTENTS_FL) != 0;
258 has_inline_data = (f->i_flags & EXT4_INLINE_DATA_FL) != 0;
261 t->i_mode = ext2fs_swab16(f->i_mode);
262 t->i_uid = ext2fs_swab16(f->i_uid);
263 t->i_size = ext2fs_swab32(f->i_size);
264 t->i_atime = ext2fs_swab32(f->i_atime);
265 t->i_ctime = ext2fs_swab32(f->i_ctime);
266 t->i_mtime = ext2fs_swab32(f->i_mtime);
267 t->i_dtime = ext2fs_swab32(f->i_dtime);
268 t->i_gid = ext2fs_swab16(f->i_gid);
269 t->i_links_count = ext2fs_swab16(f->i_links_count);
270 t->i_file_acl = ext2fs_swab32(f->i_file_acl);
271 t->i_blocks = ext2fs_swab32(f->i_blocks);
272 t->i_flags = ext2fs_swab32(f->i_flags);
273 t->i_size_high = ext2fs_swab32(f->i_size_high);
276 islnk = LINUX_S_ISLNK(t->i_mode);
277 fast_symlink = ext2fs_is_fast_symlink(EXT2_INODE(t));
278 has_extents = (t->i_flags & EXT4_EXTENTS_FL) != 0;
279 has_inline_data = (t->i_flags & EXT4_INLINE_DATA_FL) != 0;
283 * Extent data and inline data are swapped on access, not here
285 if (!has_extents && !has_inline_data && (!islnk || !fast_symlink)) {
286 for (i = 0; i < EXT2_N_BLOCKS; i++)
287 t->i_block[i] = ext2fs_swab32(f->i_block[i]);
289 for (i = 0; i < EXT2_N_BLOCKS; i++)
290 t->i_block[i] = f->i_block[i];
292 t->i_generation = ext2fs_swab32(f->i_generation);
293 t->i_faddr = ext2fs_swab32(f->i_faddr);
295 switch (fs->super->s_creator_os) {
297 t->osd1.linux1.l_i_version =
298 ext2fs_swab32(f->osd1.linux1.l_i_version);
299 t->osd2.linux2.l_i_blocks_hi =
300 ext2fs_swab16(f->osd2.linux2.l_i_blocks_hi);
301 t->osd2.linux2.l_i_file_acl_high =
302 ext2fs_swab16(f->osd2.linux2.l_i_file_acl_high);
303 t->osd2.linux2.l_i_uid_high =
304 ext2fs_swab16 (f->osd2.linux2.l_i_uid_high);
305 t->osd2.linux2.l_i_gid_high =
306 ext2fs_swab16 (f->osd2.linux2.l_i_gid_high);
307 t->osd2.linux2.l_i_checksum_lo =
308 ext2fs_swab16(f->osd2.linux2.l_i_checksum_lo);
311 t->osd1.hurd1.h_i_translator =
312 ext2fs_swab32 (f->osd1.hurd1.h_i_translator);
313 t->osd2.hurd2.h_i_frag = f->osd2.hurd2.h_i_frag;
314 t->osd2.hurd2.h_i_fsize = f->osd2.hurd2.h_i_fsize;
315 t->osd2.hurd2.h_i_mode_high =
316 ext2fs_swab16 (f->osd2.hurd2.h_i_mode_high);
317 t->osd2.hurd2.h_i_uid_high =
318 ext2fs_swab16 (f->osd2.hurd2.h_i_uid_high);
319 t->osd2.hurd2.h_i_gid_high =
320 ext2fs_swab16 (f->osd2.hurd2.h_i_gid_high);
321 t->osd2.hurd2.h_i_author =
322 ext2fs_swab32 (f->osd2.hurd2.h_i_author);
328 if (bufsize < (int) (sizeof(struct ext2_inode) + sizeof(__u16)))
329 return; /* no i_extra_isize field */
332 extra_isize = f->i_extra_isize;
333 t->i_extra_isize = ext2fs_swab16(f->i_extra_isize);
335 extra_isize = t->i_extra_isize;
336 if (extra_isize > EXT2_INODE_SIZE(fs->super) -
337 sizeof(struct ext2_inode)) {
338 /* this is error case: i_extra_size is too large */
342 return; /* Illegal inode extra_isize */
344 inode_size = EXT2_GOOD_OLD_INODE_SIZE + extra_isize;
345 if (inode_includes(inode_size, i_checksum_hi))
346 t->i_checksum_hi = ext2fs_swab16(f->i_checksum_hi);
347 if (inode_includes(inode_size, i_ctime_extra))
348 t->i_ctime_extra = ext2fs_swab32(f->i_ctime_extra);
349 if (inode_includes(inode_size, i_mtime_extra))
350 t->i_mtime_extra = ext2fs_swab32(f->i_mtime_extra);
351 if (inode_includes(inode_size, i_atime_extra))
352 t->i_atime_extra = ext2fs_swab32(f->i_atime_extra);
353 if (inode_includes(inode_size, i_crtime))
354 t->i_crtime = ext2fs_swab32(f->i_crtime);
355 if (inode_includes(inode_size, i_crtime_extra))
356 t->i_crtime_extra = ext2fs_swab32(f->i_crtime_extra);
357 if (inode_includes(inode_size, i_version_hi))
358 t->i_version_hi = ext2fs_swab32(f->i_version_hi);
359 if (inode_includes(inode_size, i_projid))
360 t->i_projid = ext2fs_swab32(f->i_projid);
361 /* catch new static fields added after i_projid */
362 EXT2FS_BUILD_BUG_ON(sizeof(struct ext2_inode_large) != 160);
364 i = sizeof(struct ext2_inode) + extra_isize + sizeof(__u32);
365 if (bufsize < (int) i)
366 return; /* no space for EA magic */
368 eaf = (__u32 *) (((char *) f) + sizeof(struct ext2_inode) +
373 attr_magic = ext2fs_swab32(attr_magic);
375 if (attr_magic != EXT2_EXT_ATTR_MAGIC)
376 return; /* it seems no magic here */
378 eat = (__u32 *) (((char *) t) + sizeof(struct ext2_inode) +
380 *eat = ext2fs_swab32(*eaf);
383 ext2fs_swap_ext_attr((char *) (eat + 1), (char *) (eaf + 1),
384 bufsize - sizeof(struct ext2_inode) -
385 extra_isize - sizeof(__u32), 0);
389 void ext2fs_swap_inode(ext2_filsys fs, struct ext2_inode *t,
390 struct ext2_inode *f, int hostorder)
392 ext2fs_swap_inode_full(fs, (struct ext2_inode_large *) t,
393 (struct ext2_inode_large *) f, hostorder,
394 sizeof(struct ext2_inode));
397 void ext2fs_swap_mmp(struct mmp_struct *mmp)
399 mmp->mmp_magic = ext2fs_swab32(mmp->mmp_magic);
400 mmp->mmp_seq = ext2fs_swab32(mmp->mmp_seq);
401 mmp->mmp_time = ext2fs_swab64(mmp->mmp_time);
402 mmp->mmp_check_interval = ext2fs_swab16(mmp->mmp_check_interval);
403 mmp->mmp_checksum = ext2fs_swab32(mmp->mmp_checksum);
406 errcode_t ext2fs_dirent_swab_in(ext2_filsys fs, char *buf, int flags)
408 return ext2fs_dirent_swab_in2(fs, buf, fs->blocksize, flags);
411 errcode_t ext2fs_dirent_swab_in2(ext2_filsys fs, char *buf,
412 size_t size, int flags)
416 struct ext2_dir_entry *dirent;
417 unsigned int name_len, rec_len;
420 end = (char *) buf + size;
422 dirent = (struct ext2_dir_entry *) p;
423 dirent->inode = ext2fs_swab32(dirent->inode);
424 dirent->rec_len = ext2fs_swab16(dirent->rec_len);
425 dirent->name_len = ext2fs_swab16(dirent->name_len);
426 name_len = dirent->name_len;
427 if (flags & EXT2_DIRBLOCK_V2_STRUCT)
428 dirent->name_len = ext2fs_swab16(dirent->name_len);
429 retval = ext2fs_get_rec_len(fs, dirent, &rec_len);
432 if ((rec_len < 8) || (rec_len % 4)) {
434 retval = EXT2_ET_DIR_CORRUPTED;
435 } else if (((name_len & 0xFF) + 8) > rec_len)
436 retval = EXT2_ET_DIR_CORRUPTED;
443 errcode_t ext2fs_dirent_swab_out(ext2_filsys fs, char *buf, int flags)
445 return ext2fs_dirent_swab_out2(fs, buf, fs->blocksize, flags);
448 errcode_t ext2fs_dirent_swab_out2(ext2_filsys fs, char *buf,
449 size_t size, int flags)
453 unsigned int rec_len;
454 struct ext2_dir_entry *dirent;
459 dirent = (struct ext2_dir_entry *) p;
460 retval = ext2fs_get_rec_len(fs, dirent, &rec_len);
465 ext2fs_free_mem(&buf);
466 return EXT2_ET_DIR_CORRUPTED;
469 dirent->inode = ext2fs_swab32(dirent->inode);
470 dirent->rec_len = ext2fs_swab16(dirent->rec_len);
471 dirent->name_len = ext2fs_swab16(dirent->name_len);
473 if (flags & EXT2_DIRBLOCK_V2_STRUCT)
474 dirent->name_len = ext2fs_swab16(dirent->name_len);