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 Public
8 * License.
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_frag_size = ext2fs_swab32(sb->s_log_frag_size);
35 sb->s_blocks_per_group = ext2fs_swab32(sb->s_blocks_per_group);
36 sb->s_frags_per_group = ext2fs_swab32(sb->s_frags_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_kbytes_written = ext2fs_swab64(sb->s_kbytes_written);
74 for (i=0; i < 4; i++)
75 sb->s_hash_seed[i] = ext2fs_swab32(sb->s_hash_seed[i]);
76
77 /* if journal backup is for a valid extent-based journal... */
78 if (!ext2fs_extent_header_verify(sb->s_jnl_blocks,
79 sizeof(sb->s_jnl_blocks))) {
80 /* ... swap only the journal i_size */
81 sb->s_jnl_blocks[16] = ext2fs_swab32(sb->s_jnl_blocks[16]);
82 /* and the extent data is not swapped on read */
83 return;
84 }
85
86 /* direct/indirect journal: swap it all */
87 for (i=0; i < 17; i++)
88 sb->s_jnl_blocks[i] = ext2fs_swab32(sb->s_jnl_blocks[i]);
89 }
90
ext2fs_swap_group_desc(struct ext2_group_desc * gdp)91 void ext2fs_swap_group_desc(struct ext2_group_desc *gdp)
92 {
93 gdp->bg_block_bitmap = ext2fs_swab32(gdp->bg_block_bitmap);
94 gdp->bg_inode_bitmap = ext2fs_swab32(gdp->bg_inode_bitmap);
95 gdp->bg_inode_table = ext2fs_swab32(gdp->bg_inode_table);
96 gdp->bg_free_blocks_count = ext2fs_swab16(gdp->bg_free_blocks_count);
97 gdp->bg_free_inodes_count = ext2fs_swab16(gdp->bg_free_inodes_count);
98 gdp->bg_used_dirs_count = ext2fs_swab16(gdp->bg_used_dirs_count);
99 gdp->bg_flags = ext2fs_swab16(gdp->bg_flags);
100 gdp->bg_itable_unused = ext2fs_swab16(gdp->bg_itable_unused);
101 gdp->bg_checksum = ext2fs_swab16(gdp->bg_checksum);
102 }
103
ext2fs_swap_ext_attr_header(struct ext2_ext_attr_header * to_header,struct ext2_ext_attr_header * from_header)104 void ext2fs_swap_ext_attr_header(struct ext2_ext_attr_header *to_header,
105 struct ext2_ext_attr_header *from_header)
106 {
107 int n;
108
109 to_header->h_magic = ext2fs_swab32(from_header->h_magic);
110 to_header->h_blocks = ext2fs_swab32(from_header->h_blocks);
111 to_header->h_refcount = ext2fs_swab32(from_header->h_refcount);
112 to_header->h_hash = ext2fs_swab32(from_header->h_hash);
113 for (n = 0; n < 4; n++)
114 to_header->h_reserved[n] =
115 ext2fs_swab32(from_header->h_reserved[n]);
116 }
117
ext2fs_swap_ext_attr_entry(struct ext2_ext_attr_entry * to_entry,struct ext2_ext_attr_entry * from_entry)118 void ext2fs_swap_ext_attr_entry(struct ext2_ext_attr_entry *to_entry,
119 struct ext2_ext_attr_entry *from_entry)
120 {
121 to_entry->e_value_offs = ext2fs_swab16(from_entry->e_value_offs);
122 to_entry->e_value_block = ext2fs_swab32(from_entry->e_value_block);
123 to_entry->e_value_size = ext2fs_swab32(from_entry->e_value_size);
124 to_entry->e_hash = ext2fs_swab32(from_entry->e_hash);
125 }
126
ext2fs_swap_ext_attr(char * to,char * from,int bufsize,int has_header)127 void ext2fs_swap_ext_attr(char *to, char *from, int bufsize, int has_header)
128 {
129 struct ext2_ext_attr_header *from_header =
130 (struct ext2_ext_attr_header *)from;
131 struct ext2_ext_attr_header *to_header =
132 (struct ext2_ext_attr_header *)to;
133 struct ext2_ext_attr_entry *from_entry, *to_entry;
134 char *from_end = (char *)from_header + bufsize;
135
136 if (to_header != from_header)
137 memcpy(to_header, from_header, bufsize);
138
139 if (has_header) {
140 ext2fs_swap_ext_attr_header(to_header, from_header);
141
142 from_entry = (struct ext2_ext_attr_entry *)(from_header+1);
143 to_entry = (struct ext2_ext_attr_entry *)(to_header+1);
144 } else {
145 from_entry = (struct ext2_ext_attr_entry *)from_header;
146 to_entry = (struct ext2_ext_attr_entry *)to_header;
147 }
148
149 while ((char *)from_entry < from_end && *(__u32 *)from_entry) {
150 ext2fs_swap_ext_attr_entry(to_entry, from_entry);
151 from_entry = EXT2_EXT_ATTR_NEXT(from_entry);
152 to_entry = EXT2_EXT_ATTR_NEXT(to_entry);
153 }
154 }
155
ext2fs_swap_inode_full(ext2_filsys fs,struct ext2_inode_large * t,struct ext2_inode_large * f,int hostorder,int bufsize)156 void ext2fs_swap_inode_full(ext2_filsys fs, struct ext2_inode_large *t,
157 struct ext2_inode_large *f, int hostorder,
158 int bufsize)
159 {
160 unsigned i, has_data_blocks, extra_isize, attr_magic;
161 int has_extents = 0;
162 int islnk = 0;
163 __u32 *eaf, *eat;
164
165 if (hostorder && LINUX_S_ISLNK(f->i_mode))
166 islnk = 1;
167 t->i_mode = ext2fs_swab16(f->i_mode);
168 if (!hostorder && LINUX_S_ISLNK(t->i_mode))
169 islnk = 1;
170 t->i_uid = ext2fs_swab16(f->i_uid);
171 t->i_size = ext2fs_swab32(f->i_size);
172 t->i_atime = ext2fs_swab32(f->i_atime);
173 t->i_ctime = ext2fs_swab32(f->i_ctime);
174 t->i_mtime = ext2fs_swab32(f->i_mtime);
175 t->i_dtime = ext2fs_swab32(f->i_dtime);
176 t->i_gid = ext2fs_swab16(f->i_gid);
177 t->i_links_count = ext2fs_swab16(f->i_links_count);
178 t->i_file_acl = ext2fs_swab32(f->i_file_acl);
179 if (hostorder)
180 has_data_blocks = ext2fs_inode_data_blocks(fs,
181 (struct ext2_inode *) f);
182 t->i_blocks = ext2fs_swab32(f->i_blocks);
183 if (!hostorder)
184 has_data_blocks = ext2fs_inode_data_blocks(fs,
185 (struct ext2_inode *) t);
186 if (hostorder && (f->i_flags & EXT4_EXTENTS_FL))
187 has_extents = 1;
188 t->i_flags = ext2fs_swab32(f->i_flags);
189 if (!hostorder && (t->i_flags & EXT4_EXTENTS_FL))
190 has_extents = 1;
191 t->i_dir_acl = ext2fs_swab32(f->i_dir_acl);
192 /* extent data are swapped on access, not here */
193 if (!has_extents && (!islnk || has_data_blocks)) {
194 for (i = 0; i < EXT2_N_BLOCKS; i++)
195 t->i_block[i] = ext2fs_swab32(f->i_block[i]);
196 } else if (t != f) {
197 for (i = 0; i < EXT2_N_BLOCKS; i++)
198 t->i_block[i] = f->i_block[i];
199 }
200 t->i_generation = ext2fs_swab32(f->i_generation);
201 t->i_faddr = ext2fs_swab32(f->i_faddr);
202
203 switch (fs->super->s_creator_os) {
204 case EXT2_OS_LINUX:
205 t->osd1.linux1.l_i_version =
206 ext2fs_swab32(f->osd1.linux1.l_i_version);
207 t->osd2.linux2.l_i_blocks_hi =
208 ext2fs_swab16(f->osd2.linux2.l_i_blocks_hi);
209 t->osd2.linux2.l_i_file_acl_high =
210 ext2fs_swab16(f->osd2.linux2.l_i_file_acl_high);
211 t->osd2.linux2.l_i_uid_high =
212 ext2fs_swab16 (f->osd2.linux2.l_i_uid_high);
213 t->osd2.linux2.l_i_gid_high =
214 ext2fs_swab16 (f->osd2.linux2.l_i_gid_high);
215 t->osd2.linux2.l_i_reserved2 =
216 ext2fs_swab32(f->osd2.linux2.l_i_reserved2);
217 break;
218 case EXT2_OS_HURD:
219 t->osd1.hurd1.h_i_translator =
220 ext2fs_swab32 (f->osd1.hurd1.h_i_translator);
221 t->osd2.hurd2.h_i_frag = f->osd2.hurd2.h_i_frag;
222 t->osd2.hurd2.h_i_fsize = f->osd2.hurd2.h_i_fsize;
223 t->osd2.hurd2.h_i_mode_high =
224 ext2fs_swab16 (f->osd2.hurd2.h_i_mode_high);
225 t->osd2.hurd2.h_i_uid_high =
226 ext2fs_swab16 (f->osd2.hurd2.h_i_uid_high);
227 t->osd2.hurd2.h_i_gid_high =
228 ext2fs_swab16 (f->osd2.hurd2.h_i_gid_high);
229 t->osd2.hurd2.h_i_author =
230 ext2fs_swab32 (f->osd2.hurd2.h_i_author);
231 break;
232 default:
233 break;
234 }
235
236 if (bufsize < (int) (sizeof(struct ext2_inode) + sizeof(__u16)))
237 return; /* no i_extra_isize field */
238
239 if (hostorder)
240 extra_isize = f->i_extra_isize;
241 t->i_extra_isize = ext2fs_swab16(f->i_extra_isize);
242 if (!hostorder)
243 extra_isize = t->i_extra_isize;
244 if (extra_isize > EXT2_INODE_SIZE(fs->super) -
245 sizeof(struct ext2_inode)) {
246 /* this is error case: i_extra_size is too large */
247 return;
248 }
249
250 i = sizeof(struct ext2_inode) + extra_isize + sizeof(__u32);
251 if (bufsize < (int) i)
252 return; /* no space for EA magic */
253
254 eaf = (__u32 *) (((char *) f) + sizeof(struct ext2_inode) +
255 extra_isize);
256
257 attr_magic = *eaf;
258 if (!hostorder)
259 attr_magic = ext2fs_swab32(attr_magic);
260
261 if (attr_magic != EXT2_EXT_ATTR_MAGIC)
262 return; /* it seems no magic here */
263
264 eat = (__u32 *) (((char *) t) + sizeof(struct ext2_inode) +
265 extra_isize);
266 *eat = ext2fs_swab32(*eaf);
267
268 /* convert EA(s) */
269 ext2fs_swap_ext_attr((char *) (eat + 1), (char *) (eaf + 1),
270 bufsize - sizeof(struct ext2_inode) -
271 extra_isize - sizeof(__u32), 0);
272
273 }
274
ext2fs_swap_inode(ext2_filsys fs,struct ext2_inode * t,struct ext2_inode * f,int hostorder)275 void ext2fs_swap_inode(ext2_filsys fs, struct ext2_inode *t,
276 struct ext2_inode *f, int hostorder)
277 {
278 ext2fs_swap_inode_full(fs, (struct ext2_inode_large *) t,
279 (struct ext2_inode_large *) f, hostorder,
280 sizeof(struct ext2_inode));
281 }
282
283 #endif
284