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 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 } 102 103 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 } 143 144 void ext2fs_swap_group_desc(struct ext2_group_desc *gdp) 145 { 146 ext2fs_swap_group_desc2(0, gdp); 147 } 148 149 150 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 } 163 164 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 } 172 173 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 } 201 202 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 } 335 336 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 } 343 344 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