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 "config.h" 13 #include <stdio.h> 14 #if HAVE_UNISTD_H 15 #include <unistd.h> 16 #endif 17 #include <string.h> 18 #include <time.h> 19 20 #include "ext2_fs.h" 21 #include "ext2fs.h" 22 #include <ext2fs/ext2_ext_attr.h> 23 24 #ifdef WORDS_BIGENDIAN 25 void ext2fs_swap_super(struct ext2_super_block * sb) 26 { 27 int i; 28 sb->s_inodes_count = ext2fs_swab32(sb->s_inodes_count); 29 sb->s_blocks_count = ext2fs_swab32(sb->s_blocks_count); 30 sb->s_r_blocks_count = ext2fs_swab32(sb->s_r_blocks_count); 31 sb->s_free_blocks_count = ext2fs_swab32(sb->s_free_blocks_count); 32 sb->s_free_inodes_count = ext2fs_swab32(sb->s_free_inodes_count); 33 sb->s_first_data_block = ext2fs_swab32(sb->s_first_data_block); 34 sb->s_log_block_size = ext2fs_swab32(sb->s_log_block_size); 35 sb->s_log_cluster_size = ext2fs_swab32(sb->s_log_cluster_size); 36 sb->s_blocks_per_group = ext2fs_swab32(sb->s_blocks_per_group); 37 sb->s_clusters_per_group = ext2fs_swab32(sb->s_clusters_per_group); 38 sb->s_inodes_per_group = ext2fs_swab32(sb->s_inodes_per_group); 39 sb->s_mtime = ext2fs_swab32(sb->s_mtime); 40 sb->s_wtime = ext2fs_swab32(sb->s_wtime); 41 sb->s_mnt_count = ext2fs_swab16(sb->s_mnt_count); 42 sb->s_max_mnt_count = ext2fs_swab16(sb->s_max_mnt_count); 43 sb->s_magic = ext2fs_swab16(sb->s_magic); 44 sb->s_state = ext2fs_swab16(sb->s_state); 45 sb->s_errors = ext2fs_swab16(sb->s_errors); 46 sb->s_minor_rev_level = ext2fs_swab16(sb->s_minor_rev_level); 47 sb->s_lastcheck = ext2fs_swab32(sb->s_lastcheck); 48 sb->s_checkinterval = ext2fs_swab32(sb->s_checkinterval); 49 sb->s_creator_os = ext2fs_swab32(sb->s_creator_os); 50 sb->s_rev_level = ext2fs_swab32(sb->s_rev_level); 51 sb->s_def_resuid = ext2fs_swab16(sb->s_def_resuid); 52 sb->s_def_resgid = ext2fs_swab16(sb->s_def_resgid); 53 sb->s_first_ino = ext2fs_swab32(sb->s_first_ino); 54 sb->s_inode_size = ext2fs_swab16(sb->s_inode_size); 55 sb->s_block_group_nr = ext2fs_swab16(sb->s_block_group_nr); 56 sb->s_feature_compat = ext2fs_swab32(sb->s_feature_compat); 57 sb->s_feature_incompat = ext2fs_swab32(sb->s_feature_incompat); 58 sb->s_feature_ro_compat = ext2fs_swab32(sb->s_feature_ro_compat); 59 sb->s_algorithm_usage_bitmap = ext2fs_swab32(sb->s_algorithm_usage_bitmap); 60 sb->s_reserved_gdt_blocks = ext2fs_swab16(sb->s_reserved_gdt_blocks); 61 sb->s_journal_inum = ext2fs_swab32(sb->s_journal_inum); 62 sb->s_journal_dev = ext2fs_swab32(sb->s_journal_dev); 63 sb->s_last_orphan = ext2fs_swab32(sb->s_last_orphan); 64 sb->s_desc_size = ext2fs_swab16(sb->s_desc_size); 65 sb->s_default_mount_opts = ext2fs_swab32(sb->s_default_mount_opts); 66 sb->s_first_meta_bg = ext2fs_swab32(sb->s_first_meta_bg); 67 sb->s_mkfs_time = ext2fs_swab32(sb->s_mkfs_time); 68 sb->s_blocks_count_hi = ext2fs_swab32(sb->s_blocks_count_hi); 69 sb->s_r_blocks_count_hi = ext2fs_swab32(sb->s_r_blocks_count_hi); 70 sb->s_free_blocks_hi = ext2fs_swab32(sb->s_free_blocks_hi); 71 sb->s_min_extra_isize = ext2fs_swab16(sb->s_min_extra_isize); 72 sb->s_want_extra_isize = ext2fs_swab16(sb->s_want_extra_isize); 73 sb->s_flags = ext2fs_swab32(sb->s_flags); 74 sb->s_mmp_update_interval = ext2fs_swab16(sb->s_mmp_update_interval); 75 sb->s_mmp_block = ext2fs_swab64(sb->s_mmp_block); 76 sb->s_kbytes_written = ext2fs_swab64(sb->s_kbytes_written); 77 sb->s_snapshot_inum = ext2fs_swab32(sb->s_snapshot_inum); 78 sb->s_snapshot_id = ext2fs_swab32(sb->s_snapshot_id); 79 sb->s_snapshot_r_blocks_count = 80 ext2fs_swab64(sb->s_snapshot_r_blocks_count); 81 sb->s_snapshot_list = ext2fs_swab32(sb->s_snapshot_list); 82 sb->s_usr_quota_inum = ext2fs_swab32(sb->s_usr_quota_inum); 83 sb->s_grp_quota_inum = ext2fs_swab32(sb->s_grp_quota_inum); 84 sb->s_overhead_blocks = ext2fs_swab32(sb->s_overhead_blocks); 85 sb->s_checksum = ext2fs_swab32(sb->s_checksum); 86 87 for (i=0; i < 4; i++) 88 sb->s_hash_seed[i] = ext2fs_swab32(sb->s_hash_seed[i]); 89 90 /* if journal backup is for a valid extent-based journal... */ 91 if (ext2fs_extent_header_verify(sb->s_jnl_blocks, 92 sizeof(sb->s_jnl_blocks)) == 0) { 93 /* ... swap only the journal i_size and i_size_high, 94 * and the extent data is not swapped on read */ 95 i = 15; 96 } else { 97 /* direct/indirect journal: swap it all */ 98 i = 0; 99 } 100 for (; i < 17; i++) 101 sb->s_jnl_blocks[i] = ext2fs_swab32(sb->s_jnl_blocks[i]); 102 sb->s_backup_bgs[0] = ext2fs_swab32(sb->s_backup_bgs[0]); 103 sb->s_backup_bgs[1] = ext2fs_swab32(sb->s_backup_bgs[1]); 104 sb->s_checksum_seed = ext2fs_swab32(sb->s_checksum_seed); 105 } 106 107 void ext2fs_swap_group_desc2(ext2_filsys fs, struct ext2_group_desc *gdp) 108 { 109 struct ext4_group_desc *gdp4 = (struct ext4_group_desc *)gdp; 110 111 /* Do the 32-bit parts first */ 112 gdp->bg_block_bitmap = ext2fs_swab32(gdp->bg_block_bitmap); 113 gdp->bg_inode_bitmap = ext2fs_swab32(gdp->bg_inode_bitmap); 114 gdp->bg_inode_table = ext2fs_swab32(gdp->bg_inode_table); 115 gdp->bg_free_blocks_count = ext2fs_swab16(gdp->bg_free_blocks_count); 116 gdp->bg_free_inodes_count = ext2fs_swab16(gdp->bg_free_inodes_count); 117 gdp->bg_used_dirs_count = ext2fs_swab16(gdp->bg_used_dirs_count); 118 gdp->bg_flags = ext2fs_swab16(gdp->bg_flags); 119 gdp->bg_exclude_bitmap_lo = ext2fs_swab32(gdp->bg_exclude_bitmap_lo); 120 gdp->bg_block_bitmap_csum_lo = 121 ext2fs_swab16(gdp->bg_block_bitmap_csum_lo); 122 gdp->bg_inode_bitmap_csum_lo = 123 ext2fs_swab16(gdp->bg_inode_bitmap_csum_lo); 124 gdp->bg_itable_unused = ext2fs_swab16(gdp->bg_itable_unused); 125 gdp->bg_checksum = ext2fs_swab16(gdp->bg_checksum); 126 /* If we're 32-bit, we're done */ 127 if (fs == NULL || EXT2_DESC_SIZE(fs->super) < EXT2_MIN_DESC_SIZE_64BIT) 128 return; 129 130 /* Swap the 64-bit parts */ 131 gdp4->bg_block_bitmap_hi = ext2fs_swab32(gdp4->bg_block_bitmap_hi); 132 gdp4->bg_inode_bitmap_hi = ext2fs_swab32(gdp4->bg_inode_bitmap_hi); 133 gdp4->bg_inode_table_hi = ext2fs_swab32(gdp4->bg_inode_table_hi); 134 gdp4->bg_free_blocks_count_hi = 135 ext2fs_swab16(gdp4->bg_free_blocks_count_hi); 136 gdp4->bg_free_inodes_count_hi = 137 ext2fs_swab16(gdp4->bg_free_inodes_count_hi); 138 gdp4->bg_used_dirs_count_hi = 139 ext2fs_swab16(gdp4->bg_used_dirs_count_hi); 140 gdp4->bg_itable_unused_hi = ext2fs_swab16(gdp4->bg_itable_unused_hi); 141 gdp4->bg_exclude_bitmap_hi = ext2fs_swab16(gdp4->bg_exclude_bitmap_hi); 142 gdp4->bg_block_bitmap_csum_hi = 143 ext2fs_swab16(gdp4->bg_block_bitmap_csum_hi); 144 gdp4->bg_inode_bitmap_csum_hi = 145 ext2fs_swab16(gdp4->bg_inode_bitmap_csum_hi); 146 } 147 148 void ext2fs_swap_group_desc(struct ext2_group_desc *gdp) 149 { 150 ext2fs_swap_group_desc2(0, gdp); 151 } 152 153 154 void ext2fs_swap_ext_attr_header(struct ext2_ext_attr_header *to_header, 155 struct ext2_ext_attr_header *from_header) 156 { 157 int n; 158 159 to_header->h_magic = ext2fs_swab32(from_header->h_magic); 160 to_header->h_blocks = ext2fs_swab32(from_header->h_blocks); 161 to_header->h_refcount = ext2fs_swab32(from_header->h_refcount); 162 to_header->h_hash = ext2fs_swab32(from_header->h_hash); 163 to_header->h_checksum = ext2fs_swab32(from_header->h_checksum); 164 for (n = 0; n < 3; n++) 165 to_header->h_reserved[n] = 166 ext2fs_swab32(from_header->h_reserved[n]); 167 } 168 169 void ext2fs_swap_ext_attr_entry(struct ext2_ext_attr_entry *to_entry, 170 struct ext2_ext_attr_entry *from_entry) 171 { 172 to_entry->e_value_offs = ext2fs_swab16(from_entry->e_value_offs); 173 to_entry->e_value_block = ext2fs_swab32(from_entry->e_value_block); 174 to_entry->e_value_size = ext2fs_swab32(from_entry->e_value_size); 175 to_entry->e_hash = ext2fs_swab32(from_entry->e_hash); 176 } 177 178 void ext2fs_swap_ext_attr(char *to, char *from, int bufsize, int has_header) 179 { 180 struct ext2_ext_attr_header *from_header = 181 (struct ext2_ext_attr_header *)from; 182 struct ext2_ext_attr_header *to_header = 183 (struct ext2_ext_attr_header *)to; 184 struct ext2_ext_attr_entry *from_entry, *to_entry; 185 char *from_end = (char *)from_header + bufsize; 186 187 if (to_header != from_header) 188 memcpy(to_header, from_header, bufsize); 189 190 if (has_header) { 191 ext2fs_swap_ext_attr_header(to_header, from_header); 192 193 from_entry = (struct ext2_ext_attr_entry *)(from_header+1); 194 to_entry = (struct ext2_ext_attr_entry *)(to_header+1); 195 } else { 196 from_entry = (struct ext2_ext_attr_entry *)from_header; 197 to_entry = (struct ext2_ext_attr_entry *)to_header; 198 } 199 200 while ((char *)from_entry < from_end && 201 (char *)EXT2_EXT_ATTR_NEXT(from_entry) <= from_end && 202 *(__u32 *)from_entry) { 203 ext2fs_swap_ext_attr_entry(to_entry, from_entry); 204 from_entry = EXT2_EXT_ATTR_NEXT(from_entry); 205 to_entry = EXT2_EXT_ATTR_NEXT(to_entry); 206 } 207 } 208 209 void ext2fs_swap_inode_full(ext2_filsys fs, struct ext2_inode_large *t, 210 struct ext2_inode_large *f, int hostorder, 211 int bufsize) 212 { 213 unsigned i, has_data_blocks, extra_isize, attr_magic; 214 int has_extents = 0; 215 int has_inline_data = 0; 216 int islnk = 0; 217 int inode_size; 218 __u32 *eaf, *eat; 219 220 if (hostorder && LINUX_S_ISLNK(f->i_mode)) 221 islnk = 1; 222 t->i_mode = ext2fs_swab16(f->i_mode); 223 if (!hostorder && LINUX_S_ISLNK(t->i_mode)) 224 islnk = 1; 225 t->i_uid = ext2fs_swab16(f->i_uid); 226 t->i_size = ext2fs_swab32(f->i_size); 227 t->i_atime = ext2fs_swab32(f->i_atime); 228 t->i_ctime = ext2fs_swab32(f->i_ctime); 229 t->i_mtime = ext2fs_swab32(f->i_mtime); 230 t->i_dtime = ext2fs_swab32(f->i_dtime); 231 t->i_gid = ext2fs_swab16(f->i_gid); 232 t->i_links_count = ext2fs_swab16(f->i_links_count); 233 t->i_file_acl = ext2fs_swab32(f->i_file_acl); 234 if (hostorder) 235 has_data_blocks = ext2fs_inode_data_blocks(fs, 236 (struct ext2_inode *) f); 237 t->i_blocks = ext2fs_swab32(f->i_blocks); 238 if (!hostorder) 239 has_data_blocks = ext2fs_inode_data_blocks(fs, 240 (struct ext2_inode *) t); 241 if (hostorder && (f->i_flags & EXT4_EXTENTS_FL)) 242 has_extents = 1; 243 if (hostorder && (f->i_flags & EXT4_INLINE_DATA_FL)) 244 has_inline_data = 1; 245 t->i_flags = ext2fs_swab32(f->i_flags); 246 if (!hostorder && (t->i_flags & EXT4_EXTENTS_FL)) 247 has_extents = 1; 248 if (!hostorder && (t->i_flags & EXT4_INLINE_DATA_FL)) 249 has_inline_data = 1; 250 t->i_dir_acl = ext2fs_swab32(f->i_dir_acl); 251 /* 252 * Extent data and inline data are swapped on access, not here 253 */ 254 if (!has_extents && !has_inline_data && (!islnk || has_data_blocks)) { 255 for (i = 0; i < EXT2_N_BLOCKS; i++) 256 t->i_block[i] = ext2fs_swab32(f->i_block[i]); 257 } else if (t != f) { 258 for (i = 0; i < EXT2_N_BLOCKS; i++) 259 t->i_block[i] = f->i_block[i]; 260 } 261 t->i_generation = ext2fs_swab32(f->i_generation); 262 t->i_faddr = ext2fs_swab32(f->i_faddr); 263 264 switch (fs->super->s_creator_os) { 265 case EXT2_OS_LINUX: 266 t->osd1.linux1.l_i_version = 267 ext2fs_swab32(f->osd1.linux1.l_i_version); 268 t->osd2.linux2.l_i_blocks_hi = 269 ext2fs_swab16(f->osd2.linux2.l_i_blocks_hi); 270 t->osd2.linux2.l_i_file_acl_high = 271 ext2fs_swab16(f->osd2.linux2.l_i_file_acl_high); 272 t->osd2.linux2.l_i_uid_high = 273 ext2fs_swab16 (f->osd2.linux2.l_i_uid_high); 274 t->osd2.linux2.l_i_gid_high = 275 ext2fs_swab16 (f->osd2.linux2.l_i_gid_high); 276 t->osd2.linux2.l_i_checksum_lo = 277 ext2fs_swab16(f->osd2.linux2.l_i_checksum_lo); 278 break; 279 case EXT2_OS_HURD: 280 t->osd1.hurd1.h_i_translator = 281 ext2fs_swab32 (f->osd1.hurd1.h_i_translator); 282 t->osd2.hurd2.h_i_frag = f->osd2.hurd2.h_i_frag; 283 t->osd2.hurd2.h_i_fsize = f->osd2.hurd2.h_i_fsize; 284 t->osd2.hurd2.h_i_mode_high = 285 ext2fs_swab16 (f->osd2.hurd2.h_i_mode_high); 286 t->osd2.hurd2.h_i_uid_high = 287 ext2fs_swab16 (f->osd2.hurd2.h_i_uid_high); 288 t->osd2.hurd2.h_i_gid_high = 289 ext2fs_swab16 (f->osd2.hurd2.h_i_gid_high); 290 t->osd2.hurd2.h_i_author = 291 ext2fs_swab32 (f->osd2.hurd2.h_i_author); 292 break; 293 default: 294 break; 295 } 296 297 if (bufsize < (int) (sizeof(struct ext2_inode) + sizeof(__u16))) 298 return; /* no i_extra_isize field */ 299 300 if (hostorder) 301 extra_isize = f->i_extra_isize; 302 t->i_extra_isize = ext2fs_swab16(f->i_extra_isize); 303 if (!hostorder) 304 extra_isize = t->i_extra_isize; 305 if (extra_isize > EXT2_INODE_SIZE(fs->super) - 306 sizeof(struct ext2_inode)) { 307 /* this is error case: i_extra_size is too large */ 308 return; 309 } 310 if (extra_isize & 3) 311 return; /* Illegal inode extra_isize */ 312 313 inode_size = EXT2_GOOD_OLD_INODE_SIZE + extra_isize; 314 if (inode_includes(inode_size, i_checksum_hi)) 315 t->i_checksum_hi = ext2fs_swab16(f->i_checksum_hi); 316 if (inode_includes(inode_size, i_ctime_extra)) 317 t->i_ctime_extra = ext2fs_swab32(f->i_ctime_extra); 318 if (inode_includes(inode_size, i_mtime_extra)) 319 t->i_mtime_extra = ext2fs_swab32(f->i_mtime_extra); 320 if (inode_includes(inode_size, i_atime_extra)) 321 t->i_atime_extra = ext2fs_swab32(f->i_atime_extra); 322 if (inode_includes(inode_size, i_crtime)) 323 t->i_crtime = ext2fs_swab32(f->i_crtime); 324 if (inode_includes(inode_size, i_crtime_extra)) 325 t->i_crtime_extra = ext2fs_swab32(f->i_crtime_extra); 326 if (inode_includes(inode_size, i_version_hi)) 327 t->i_version_hi = ext2fs_swab32(f->i_version_hi); 328 if (inode_includes(inode_size, i_projid)) 329 t->i_projid = ext2fs_swab16(f->i_projid); 330 331 i = sizeof(struct ext2_inode) + extra_isize + sizeof(__u32); 332 if (bufsize < (int) i) 333 return; /* no space for EA magic */ 334 335 eaf = (__u32 *) (((char *) f) + sizeof(struct ext2_inode) + 336 extra_isize); 337 338 attr_magic = *eaf; 339 if (!hostorder) 340 attr_magic = ext2fs_swab32(attr_magic); 341 342 if (attr_magic != EXT2_EXT_ATTR_MAGIC) 343 return; /* it seems no magic here */ 344 345 eat = (__u32 *) (((char *) t) + sizeof(struct ext2_inode) + 346 extra_isize); 347 *eat = ext2fs_swab32(*eaf); 348 349 /* convert EA(s) */ 350 ext2fs_swap_ext_attr((char *) (eat + 1), (char *) (eaf + 1), 351 bufsize - sizeof(struct ext2_inode) - 352 extra_isize - sizeof(__u32), 0); 353 354 } 355 356 void ext2fs_swap_inode(ext2_filsys fs, struct ext2_inode *t, 357 struct ext2_inode *f, int hostorder) 358 { 359 ext2fs_swap_inode_full(fs, (struct ext2_inode_large *) t, 360 (struct ext2_inode_large *) f, hostorder, 361 sizeof(struct ext2_inode)); 362 } 363 364 void ext2fs_swap_mmp(struct mmp_struct *mmp) 365 { 366 mmp->mmp_magic = ext2fs_swab32(mmp->mmp_magic); 367 mmp->mmp_seq = ext2fs_swab32(mmp->mmp_seq); 368 mmp->mmp_time = ext2fs_swab64(mmp->mmp_time); 369 mmp->mmp_check_interval = ext2fs_swab16(mmp->mmp_check_interval); 370 mmp->mmp_checksum = ext2fs_swab32(mmp->mmp_checksum); 371 } 372 373 errcode_t ext2fs_dirent_swab_in(ext2_filsys fs, char *buf, int flags) 374 { 375 return ext2fs_dirent_swab_in2(fs, buf, fs->blocksize, flags); 376 } 377 378 errcode_t ext2fs_dirent_swab_in2(ext2_filsys fs, char *buf, 379 size_t size, int flags) 380 { 381 errcode_t retval; 382 char *p, *end; 383 struct ext2_dir_entry *dirent; 384 unsigned int name_len, rec_len; 385 386 p = (char *) buf; 387 end = (char *) buf + size; 388 while (p < end-8) { 389 dirent = (struct ext2_dir_entry *) p; 390 dirent->inode = ext2fs_swab32(dirent->inode); 391 dirent->rec_len = ext2fs_swab16(dirent->rec_len); 392 dirent->name_len = ext2fs_swab16(dirent->name_len); 393 name_len = dirent->name_len; 394 if (flags & EXT2_DIRBLOCK_V2_STRUCT) 395 dirent->name_len = ext2fs_swab16(dirent->name_len); 396 retval = ext2fs_get_rec_len(fs, dirent, &rec_len); 397 if (retval) 398 return retval; 399 if ((rec_len < 8) || (rec_len % 4)) { 400 rec_len = 8; 401 retval = EXT2_ET_DIR_CORRUPTED; 402 } else if (((name_len & 0xFF) + 8) > rec_len) 403 retval = EXT2_ET_DIR_CORRUPTED; 404 p += rec_len; 405 } 406 407 return 0; 408 } 409 410 errcode_t ext2fs_dirent_swab_out(ext2_filsys fs, char *buf, int flags) 411 { 412 return ext2fs_dirent_swab_out2(fs, buf, fs->blocksize, flags); 413 } 414 415 errcode_t ext2fs_dirent_swab_out2(ext2_filsys fs, char *buf, 416 size_t size, int flags) 417 { 418 errcode_t retval; 419 char *p, *end; 420 unsigned int rec_len; 421 struct ext2_dir_entry *dirent; 422 423 p = buf; 424 end = buf + size; 425 while (p < end) { 426 dirent = (struct ext2_dir_entry *) p; 427 retval = ext2fs_get_rec_len(fs, dirent, &rec_len); 428 if (retval) 429 return retval; 430 if ((rec_len < 8) || 431 (rec_len % 4)) { 432 ext2fs_free_mem(&buf); 433 return EXT2_ET_DIR_CORRUPTED; 434 } 435 p += rec_len; 436 dirent->inode = ext2fs_swab32(dirent->inode); 437 dirent->rec_len = ext2fs_swab16(dirent->rec_len); 438 dirent->name_len = ext2fs_swab16(dirent->name_len); 439 440 if (flags & EXT2_DIRBLOCK_V2_STRUCT) 441 dirent->name_len = ext2fs_swab16(dirent->name_len); 442 } 443 444 return 0; 445 } 446 447 #endif 448
