1 /*
2 * swapfs.c --- swap ext2 filesystem data structures
3 *
4 * Copyright (C) 1995, 1996, 2002 Theodore Ts'o.
5 *
6 * %Begin-Header%
7 * This file may be redistributed under the terms of the GNU Library
8 * General Public License, version 2.
9 * %End-Header%
10 */
11
12 #include <stdio.h>
13 #if HAVE_UNISTD_H
14 #include <unistd.h>
15 #endif
16 #include <string.h>
17 #include <time.h>
18
19 #include "ext2_fs.h"
20 #include "ext2fs.h"
21 #include <ext2fs/ext2_ext_attr.h>
22
23 #ifdef WORDS_BIGENDIAN
ext2fs_swap_super(struct ext2_super_block * sb)24 void ext2fs_swap_super(struct ext2_super_block * sb)
25 {
26 int i;
27 sb->s_inodes_count = ext2fs_swab32(sb->s_inodes_count);
28 sb->s_blocks_count = ext2fs_swab32(sb->s_blocks_count);
29 sb->s_r_blocks_count = ext2fs_swab32(sb->s_r_blocks_count);
30 sb->s_free_blocks_count = ext2fs_swab32(sb->s_free_blocks_count);
31 sb->s_free_inodes_count = ext2fs_swab32(sb->s_free_inodes_count);
32 sb->s_first_data_block = ext2fs_swab32(sb->s_first_data_block);
33 sb->s_log_block_size = ext2fs_swab32(sb->s_log_block_size);
34 sb->s_log_cluster_size = ext2fs_swab32(sb->s_log_cluster_size);
35 sb->s_blocks_per_group = ext2fs_swab32(sb->s_blocks_per_group);
36 sb->s_clusters_per_group = ext2fs_swab32(sb->s_clusters_per_group);
37 sb->s_inodes_per_group = ext2fs_swab32(sb->s_inodes_per_group);
38 sb->s_mtime = ext2fs_swab32(sb->s_mtime);
39 sb->s_wtime = ext2fs_swab32(sb->s_wtime);
40 sb->s_mnt_count = ext2fs_swab16(sb->s_mnt_count);
41 sb->s_max_mnt_count = ext2fs_swab16(sb->s_max_mnt_count);
42 sb->s_magic = ext2fs_swab16(sb->s_magic);
43 sb->s_state = ext2fs_swab16(sb->s_state);
44 sb->s_errors = ext2fs_swab16(sb->s_errors);
45 sb->s_minor_rev_level = ext2fs_swab16(sb->s_minor_rev_level);
46 sb->s_lastcheck = ext2fs_swab32(sb->s_lastcheck);
47 sb->s_checkinterval = ext2fs_swab32(sb->s_checkinterval);
48 sb->s_creator_os = ext2fs_swab32(sb->s_creator_os);
49 sb->s_rev_level = ext2fs_swab32(sb->s_rev_level);
50 sb->s_def_resuid = ext2fs_swab16(sb->s_def_resuid);
51 sb->s_def_resgid = ext2fs_swab16(sb->s_def_resgid);
52 sb->s_first_ino = ext2fs_swab32(sb->s_first_ino);
53 sb->s_inode_size = ext2fs_swab16(sb->s_inode_size);
54 sb->s_block_group_nr = ext2fs_swab16(sb->s_block_group_nr);
55 sb->s_feature_compat = ext2fs_swab32(sb->s_feature_compat);
56 sb->s_feature_incompat = ext2fs_swab32(sb->s_feature_incompat);
57 sb->s_feature_ro_compat = ext2fs_swab32(sb->s_feature_ro_compat);
58 sb->s_algorithm_usage_bitmap = ext2fs_swab32(sb->s_algorithm_usage_bitmap);
59 sb->s_reserved_gdt_blocks = ext2fs_swab16(sb->s_reserved_gdt_blocks);
60 sb->s_journal_inum = ext2fs_swab32(sb->s_journal_inum);
61 sb->s_journal_dev = ext2fs_swab32(sb->s_journal_dev);
62 sb->s_last_orphan = ext2fs_swab32(sb->s_last_orphan);
63 sb->s_desc_size = ext2fs_swab16(sb->s_desc_size);
64 sb->s_default_mount_opts = ext2fs_swab32(sb->s_default_mount_opts);
65 sb->s_first_meta_bg = ext2fs_swab32(sb->s_first_meta_bg);
66 sb->s_mkfs_time = ext2fs_swab32(sb->s_mkfs_time);
67 sb->s_blocks_count_hi = ext2fs_swab32(sb->s_blocks_count_hi);
68 sb->s_r_blocks_count_hi = ext2fs_swab32(sb->s_r_blocks_count_hi);
69 sb->s_free_blocks_hi = ext2fs_swab32(sb->s_free_blocks_hi);
70 sb->s_min_extra_isize = ext2fs_swab16(sb->s_min_extra_isize);
71 sb->s_want_extra_isize = ext2fs_swab16(sb->s_want_extra_isize);
72 sb->s_flags = ext2fs_swab32(sb->s_flags);
73 sb->s_mmp_update_interval = ext2fs_swab16(sb->s_mmp_update_interval);
74 sb->s_mmp_block = ext2fs_swab64(sb->s_mmp_block);
75 sb->s_kbytes_written = ext2fs_swab64(sb->s_kbytes_written);
76 sb->s_snapshot_inum = ext2fs_swab32(sb->s_snapshot_inum);
77 sb->s_snapshot_id = ext2fs_swab32(sb->s_snapshot_id);
78 sb->s_snapshot_r_blocks_count =
79 ext2fs_swab64(sb->s_snapshot_r_blocks_count);
80 sb->s_snapshot_list = ext2fs_swab32(sb->s_snapshot_list);
81 sb->s_usr_quota_inum = ext2fs_swab32(sb->s_usr_quota_inum);
82 sb->s_grp_quota_inum = ext2fs_swab32(sb->s_grp_quota_inum);
83 sb->s_overhead_blocks = ext2fs_swab32(sb->s_overhead_blocks);
84 sb->s_checksum = ext2fs_swab32(sb->s_checksum);
85
86 for (i=0; i < 4; i++)
87 sb->s_hash_seed[i] = ext2fs_swab32(sb->s_hash_seed[i]);
88
89 /* if journal backup is for a valid extent-based journal... */
90 if (ext2fs_extent_header_verify(sb->s_jnl_blocks,
91 sizeof(sb->s_jnl_blocks)) == 0) {
92 /* ... swap only the journal i_size and i_size_high,
93 * and the extent data is not swapped on read */
94 i = 15;
95 } else {
96 /* direct/indirect journal: swap it all */
97 i = 0;
98 }
99 for (; i < 17; i++)
100 sb->s_jnl_blocks[i] = ext2fs_swab32(sb->s_jnl_blocks[i]);
101 }
102
ext2fs_swap_group_desc2(ext2_filsys fs,struct ext2_group_desc * gdp)103 void ext2fs_swap_group_desc2(ext2_filsys fs, struct ext2_group_desc *gdp)
104 {
105 struct ext4_group_desc *gdp4 = (struct ext4_group_desc *)gdp;
106
107 /* Do the 32-bit parts first */
108 gdp->bg_block_bitmap = ext2fs_swab32(gdp->bg_block_bitmap);
109 gdp->bg_inode_bitmap = ext2fs_swab32(gdp->bg_inode_bitmap);
110 gdp->bg_inode_table = ext2fs_swab32(gdp->bg_inode_table);
111 gdp->bg_free_blocks_count = ext2fs_swab16(gdp->bg_free_blocks_count);
112 gdp->bg_free_inodes_count = ext2fs_swab16(gdp->bg_free_inodes_count);
113 gdp->bg_used_dirs_count = ext2fs_swab16(gdp->bg_used_dirs_count);
114 gdp->bg_flags = ext2fs_swab16(gdp->bg_flags);
115 gdp->bg_exclude_bitmap_lo = ext2fs_swab32(gdp->bg_exclude_bitmap_lo);
116 gdp->bg_block_bitmap_csum_lo =
117 ext2fs_swab16(gdp->bg_block_bitmap_csum_lo);
118 gdp->bg_inode_bitmap_csum_lo =
119 ext2fs_swab16(gdp->bg_inode_bitmap_csum_lo);
120 gdp->bg_itable_unused = ext2fs_swab16(gdp->bg_itable_unused);
121 gdp->bg_checksum = ext2fs_swab16(gdp->bg_checksum);
122 /* If we're 32-bit, we're done */
123 if (fs == NULL || EXT2_DESC_SIZE(fs->super) < EXT2_MIN_DESC_SIZE_64BIT)
124 return;
125
126 /* Swap the 64-bit parts */
127 gdp4->bg_block_bitmap_hi = ext2fs_swab32(gdp4->bg_block_bitmap_hi);
128 gdp4->bg_inode_bitmap_hi = ext2fs_swab32(gdp4->bg_inode_bitmap_hi);
129 gdp4->bg_inode_table_hi = ext2fs_swab32(gdp4->bg_inode_table_hi);
130 gdp4->bg_free_blocks_count_hi =
131 ext2fs_swab16(gdp4->bg_free_blocks_count_hi);
132 gdp4->bg_free_inodes_count_hi =
133 ext2fs_swab16(gdp4->bg_free_inodes_count_hi);
134 gdp4->bg_used_dirs_count_hi =
135 ext2fs_swab16(gdp4->bg_used_dirs_count_hi);
136 gdp4->bg_itable_unused_hi = ext2fs_swab16(gdp4->bg_itable_unused_hi);
137 gdp4->bg_exclude_bitmap_hi = ext2fs_swab16(gdp4->bg_exclude_bitmap_hi);
138 gdp4->bg_block_bitmap_csum_hi =
139 ext2fs_swab16(gdp4->bg_block_bitmap_csum_hi);
140 gdp4->bg_inode_bitmap_csum_hi =
141 ext2fs_swab16(gdp4->bg_inode_bitmap_csum_hi);
142 }
143
ext2fs_swap_group_desc(struct ext2_group_desc * gdp)144 void ext2fs_swap_group_desc(struct ext2_group_desc *gdp)
145 {
146 ext2fs_swap_group_desc2(0, gdp);
147 }
148
149
ext2fs_swap_ext_attr_header(struct ext2_ext_attr_header * to_header,struct ext2_ext_attr_header * from_header)150 void ext2fs_swap_ext_attr_header(struct ext2_ext_attr_header *to_header,
151 struct ext2_ext_attr_header *from_header)
152 {
153 int n;
154
155 to_header->h_magic = ext2fs_swab32(from_header->h_magic);
156 to_header->h_blocks = ext2fs_swab32(from_header->h_blocks);
157 to_header->h_refcount = ext2fs_swab32(from_header->h_refcount);
158 to_header->h_hash = ext2fs_swab32(from_header->h_hash);
159 for (n = 0; n < 4; n++)
160 to_header->h_reserved[n] =
161 ext2fs_swab32(from_header->h_reserved[n]);
162 }
163
ext2fs_swap_ext_attr_entry(struct ext2_ext_attr_entry * to_entry,struct ext2_ext_attr_entry * from_entry)164 void ext2fs_swap_ext_attr_entry(struct ext2_ext_attr_entry *to_entry,
165 struct ext2_ext_attr_entry *from_entry)
166 {
167 to_entry->e_value_offs = ext2fs_swab16(from_entry->e_value_offs);
168 to_entry->e_value_block = ext2fs_swab32(from_entry->e_value_block);
169 to_entry->e_value_size = ext2fs_swab32(from_entry->e_value_size);
170 to_entry->e_hash = ext2fs_swab32(from_entry->e_hash);
171 }
172
ext2fs_swap_ext_attr(char * to,char * from,int bufsize,int has_header)173 void ext2fs_swap_ext_attr(char *to, char *from, int bufsize, int has_header)
174 {
175 struct ext2_ext_attr_header *from_header =
176 (struct ext2_ext_attr_header *)from;
177 struct ext2_ext_attr_header *to_header =
178 (struct ext2_ext_attr_header *)to;
179 struct ext2_ext_attr_entry *from_entry, *to_entry;
180 char *from_end = (char *)from_header + bufsize;
181
182 if (to_header != from_header)
183 memcpy(to_header, from_header, bufsize);
184
185 if (has_header) {
186 ext2fs_swap_ext_attr_header(to_header, from_header);
187
188 from_entry = (struct ext2_ext_attr_entry *)(from_header+1);
189 to_entry = (struct ext2_ext_attr_entry *)(to_header+1);
190 } else {
191 from_entry = (struct ext2_ext_attr_entry *)from_header;
192 to_entry = (struct ext2_ext_attr_entry *)to_header;
193 }
194
195 while ((char *)from_entry < from_end && *(__u32 *)from_entry) {
196 ext2fs_swap_ext_attr_entry(to_entry, from_entry);
197 from_entry = EXT2_EXT_ATTR_NEXT(from_entry);
198 to_entry = EXT2_EXT_ATTR_NEXT(to_entry);
199 }
200 }
201
ext2fs_swap_inode_full(ext2_filsys fs,struct ext2_inode_large * t,struct ext2_inode_large * f,int hostorder,int bufsize)202 void ext2fs_swap_inode_full(ext2_filsys fs, struct ext2_inode_large *t,
203 struct ext2_inode_large *f, int hostorder,
204 int bufsize)
205 {
206 unsigned i, has_data_blocks, extra_isize, attr_magic;
207 int has_extents = 0;
208 int islnk = 0;
209 __u32 *eaf, *eat;
210
211 if (hostorder && LINUX_S_ISLNK(f->i_mode))
212 islnk = 1;
213 t->i_mode = ext2fs_swab16(f->i_mode);
214 if (!hostorder && LINUX_S_ISLNK(t->i_mode))
215 islnk = 1;
216 t->i_uid = ext2fs_swab16(f->i_uid);
217 t->i_size = ext2fs_swab32(f->i_size);
218 t->i_atime = ext2fs_swab32(f->i_atime);
219 t->i_ctime = ext2fs_swab32(f->i_ctime);
220 t->i_mtime = ext2fs_swab32(f->i_mtime);
221 t->i_dtime = ext2fs_swab32(f->i_dtime);
222 t->i_gid = ext2fs_swab16(f->i_gid);
223 t->i_links_count = ext2fs_swab16(f->i_links_count);
224 t->i_file_acl = ext2fs_swab32(f->i_file_acl);
225 if (hostorder)
226 has_data_blocks = ext2fs_inode_data_blocks(fs,
227 (struct ext2_inode *) f);
228 t->i_blocks = ext2fs_swab32(f->i_blocks);
229 if (!hostorder)
230 has_data_blocks = ext2fs_inode_data_blocks(fs,
231 (struct ext2_inode *) t);
232 if (hostorder && (f->i_flags & EXT4_EXTENTS_FL))
233 has_extents = 1;
234 t->i_flags = ext2fs_swab32(f->i_flags);
235 if (!hostorder && (t->i_flags & EXT4_EXTENTS_FL))
236 has_extents = 1;
237 t->i_dir_acl = ext2fs_swab32(f->i_dir_acl);
238 /* extent data are swapped on access, not here */
239 if (!has_extents && (!islnk || has_data_blocks)) {
240 for (i = 0; i < EXT2_N_BLOCKS; i++)
241 t->i_block[i] = ext2fs_swab32(f->i_block[i]);
242 } else if (t != f) {
243 for (i = 0; i < EXT2_N_BLOCKS; i++)
244 t->i_block[i] = f->i_block[i];
245 }
246 t->i_generation = ext2fs_swab32(f->i_generation);
247 t->i_faddr = ext2fs_swab32(f->i_faddr);
248
249 switch (fs->super->s_creator_os) {
250 case EXT2_OS_LINUX:
251 t->osd1.linux1.l_i_version =
252 ext2fs_swab32(f->osd1.linux1.l_i_version);
253 t->osd2.linux2.l_i_blocks_hi =
254 ext2fs_swab16(f->osd2.linux2.l_i_blocks_hi);
255 t->osd2.linux2.l_i_file_acl_high =
256 ext2fs_swab16(f->osd2.linux2.l_i_file_acl_high);
257 t->osd2.linux2.l_i_uid_high =
258 ext2fs_swab16 (f->osd2.linux2.l_i_uid_high);
259 t->osd2.linux2.l_i_gid_high =
260 ext2fs_swab16 (f->osd2.linux2.l_i_gid_high);
261 t->osd2.linux2.l_i_checksum_lo =
262 ext2fs_swab16(f->osd2.linux2.l_i_checksum_lo);
263 break;
264 case EXT2_OS_HURD:
265 t->osd1.hurd1.h_i_translator =
266 ext2fs_swab32 (f->osd1.hurd1.h_i_translator);
267 t->osd2.hurd2.h_i_frag = f->osd2.hurd2.h_i_frag;
268 t->osd2.hurd2.h_i_fsize = f->osd2.hurd2.h_i_fsize;
269 t->osd2.hurd2.h_i_mode_high =
270 ext2fs_swab16 (f->osd2.hurd2.h_i_mode_high);
271 t->osd2.hurd2.h_i_uid_high =
272 ext2fs_swab16 (f->osd2.hurd2.h_i_uid_high);
273 t->osd2.hurd2.h_i_gid_high =
274 ext2fs_swab16 (f->osd2.hurd2.h_i_gid_high);
275 t->osd2.hurd2.h_i_author =
276 ext2fs_swab32 (f->osd2.hurd2.h_i_author);
277 break;
278 default:
279 break;
280 }
281
282 if (bufsize < (int) (sizeof(struct ext2_inode) + sizeof(__u16)))
283 return; /* no i_extra_isize field */
284
285 if (hostorder)
286 extra_isize = f->i_extra_isize;
287 t->i_extra_isize = ext2fs_swab16(f->i_extra_isize);
288 if (!hostorder)
289 extra_isize = t->i_extra_isize;
290 if (extra_isize > EXT2_INODE_SIZE(fs->super) -
291 sizeof(struct ext2_inode)) {
292 /* this is error case: i_extra_size is too large */
293 return;
294 }
295
296 if (extra_isize >= 4)
297 t->i_checksum_hi = ext2fs_swab16(f->i_checksum_hi);
298 if (extra_isize >= 8)
299 t->i_ctime_extra = ext2fs_swab32(f->i_ctime_extra);
300 if (extra_isize >= 12)
301 t->i_mtime_extra = ext2fs_swab32(f->i_mtime_extra);
302 if (extra_isize >= 16)
303 t->i_atime_extra = ext2fs_swab32(f->i_atime_extra);
304 if (extra_isize >= 20)
305 t->i_crtime = ext2fs_swab32(f->i_crtime);
306 if (extra_isize >= 24)
307 t->i_crtime_extra = ext2fs_swab32(f->i_crtime_extra);
308 if (extra_isize >= 28)
309 t->i_version_hi = ext2fs_swab32(f->i_version_hi);
310
311 i = sizeof(struct ext2_inode) + extra_isize + sizeof(__u32);
312 if (bufsize < (int) i)
313 return; /* no space for EA magic */
314
315 eaf = (__u32 *) (((char *) f) + sizeof(struct ext2_inode) +
316 extra_isize);
317
318 attr_magic = *eaf;
319 if (!hostorder)
320 attr_magic = ext2fs_swab32(attr_magic);
321
322 if (attr_magic != EXT2_EXT_ATTR_MAGIC)
323 return; /* it seems no magic here */
324
325 eat = (__u32 *) (((char *) t) + sizeof(struct ext2_inode) +
326 extra_isize);
327 *eat = ext2fs_swab32(*eaf);
328
329 /* convert EA(s) */
330 ext2fs_swap_ext_attr((char *) (eat + 1), (char *) (eaf + 1),
331 bufsize - sizeof(struct ext2_inode) -
332 extra_isize - sizeof(__u32), 0);
333
334 }
335
ext2fs_swap_inode(ext2_filsys fs,struct ext2_inode * t,struct ext2_inode * f,int hostorder)336 void ext2fs_swap_inode(ext2_filsys fs, struct ext2_inode *t,
337 struct ext2_inode *f, int hostorder)
338 {
339 ext2fs_swap_inode_full(fs, (struct ext2_inode_large *) t,
340 (struct ext2_inode_large *) f, hostorder,
341 sizeof(struct ext2_inode));
342 }
343
ext2fs_swap_mmp(struct mmp_struct * mmp)344 void ext2fs_swap_mmp(struct mmp_struct *mmp)
345 {
346 mmp->mmp_magic = ext2fs_swab32(mmp->mmp_magic);
347 mmp->mmp_seq = ext2fs_swab32(mmp->mmp_seq);
348 mmp->mmp_time = ext2fs_swab64(mmp->mmp_time);
349 mmp->mmp_check_interval = ext2fs_swab16(mmp->mmp_check_interval);
350 }
351
352 #endif
353