swapfs.c revision a7a63675af85b4b636e9df4961ca44ea03bf160b
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 25void 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} 103 104void ext2fs_swap_group_desc2(ext2_filsys fs, struct ext2_group_desc *gdp) 105{ 106 /* Do the 32-bit parts first */ 107 gdp->bg_block_bitmap = ext2fs_swab32(gdp->bg_block_bitmap); 108 gdp->bg_inode_bitmap = ext2fs_swab32(gdp->bg_inode_bitmap); 109 gdp->bg_inode_table = ext2fs_swab32(gdp->bg_inode_table); 110 gdp->bg_free_blocks_count = ext2fs_swab16(gdp->bg_free_blocks_count); 111 gdp->bg_free_inodes_count = ext2fs_swab16(gdp->bg_free_inodes_count); 112 gdp->bg_used_dirs_count = ext2fs_swab16(gdp->bg_used_dirs_count); 113 gdp->bg_flags = ext2fs_swab16(gdp->bg_flags); 114 gdp->bg_exclude_bitmap_lo = ext2fs_swab32(gdp->bg_exclude_bitmap_lo); 115 gdp->bg_block_bitmap_csum_lo = 116 ext2fs_swab16(gdp->bg_block_bitmap_csum_lo); 117 gdp->bg_inode_bitmap_csum_lo = 118 ext2fs_swab16(gdp->bg_inode_bitmap_csum_lo); 119 gdp->bg_itable_unused = ext2fs_swab16(gdp->bg_itable_unused); 120 gdp->bg_checksum = ext2fs_swab16(gdp->bg_checksum); 121 /* If we're 32-bit, we're done */ 122 if (fs && (!fs->super->s_desc_size || 123 (fs->super->s_desc_size < EXT2_MIN_DESC_SIZE_64BIT))) 124 return; 125 126 /* Swap the 64-bit parts */ 127 struct ext4_group_desc *gdp4 = (struct ext4_group_desc *) gdp; 128 gdp4->bg_block_bitmap_hi = ext2fs_swab32(gdp4->bg_block_bitmap_hi); 129 gdp4->bg_inode_bitmap_hi = ext2fs_swab32(gdp4->bg_inode_bitmap_hi); 130 gdp4->bg_inode_table_hi = ext2fs_swab32(gdp4->bg_inode_table_hi); 131 gdp4->bg_free_blocks_count_hi = 132 ext2fs_swab16(gdp4->bg_free_blocks_count_hi); 133 gdp4->bg_free_inodes_count_hi = 134 ext2fs_swab16(gdp4->bg_free_inodes_count_hi); 135 gdp4->bg_used_dirs_count_hi = 136 ext2fs_swab16(gdp4->bg_used_dirs_count_hi); 137 gdp4->bg_itable_unused_hi = ext2fs_swab16(gdp4->bg_itable_unused_hi); 138 gdp4->bg_exclude_bitmap_hi = ext2fs_swab16(gdp4->bg_exclude_bitmap_hi); 139 gdp4->bg_block_bitmap_csum_hi = 140 ext2fs_swab16(gdp4->bg_block_bitmap_csum_hi); 141 gdp4->bg_inode_bitmap_csum_hi = 142 ext2fs_swab16(gdp4->bg_inode_bitmap_csum_hi); 143} 144 145void ext2fs_swap_group_desc(struct ext2_group_desc *gdp) 146{ 147 ext2fs_swap_group_desc2(0, gdp); 148} 149 150 151void ext2fs_swap_ext_attr_header(struct ext2_ext_attr_header *to_header, 152 struct ext2_ext_attr_header *from_header) 153{ 154 int n; 155 156 to_header->h_magic = ext2fs_swab32(from_header->h_magic); 157 to_header->h_blocks = ext2fs_swab32(from_header->h_blocks); 158 to_header->h_refcount = ext2fs_swab32(from_header->h_refcount); 159 to_header->h_hash = ext2fs_swab32(from_header->h_hash); 160 for (n = 0; n < 4; n++) 161 to_header->h_reserved[n] = 162 ext2fs_swab32(from_header->h_reserved[n]); 163} 164 165void ext2fs_swap_ext_attr_entry(struct ext2_ext_attr_entry *to_entry, 166 struct ext2_ext_attr_entry *from_entry) 167{ 168 to_entry->e_value_offs = ext2fs_swab16(from_entry->e_value_offs); 169 to_entry->e_value_block = ext2fs_swab32(from_entry->e_value_block); 170 to_entry->e_value_size = ext2fs_swab32(from_entry->e_value_size); 171 to_entry->e_hash = ext2fs_swab32(from_entry->e_hash); 172} 173 174void ext2fs_swap_ext_attr(char *to, char *from, int bufsize, int has_header) 175{ 176 struct ext2_ext_attr_header *from_header = 177 (struct ext2_ext_attr_header *)from; 178 struct ext2_ext_attr_header *to_header = 179 (struct ext2_ext_attr_header *)to; 180 struct ext2_ext_attr_entry *from_entry, *to_entry; 181 char *from_end = (char *)from_header + bufsize; 182 183 if (to_header != from_header) 184 memcpy(to_header, from_header, bufsize); 185 186 if (has_header) { 187 ext2fs_swap_ext_attr_header(to_header, from_header); 188 189 from_entry = (struct ext2_ext_attr_entry *)(from_header+1); 190 to_entry = (struct ext2_ext_attr_entry *)(to_header+1); 191 } else { 192 from_entry = (struct ext2_ext_attr_entry *)from_header; 193 to_entry = (struct ext2_ext_attr_entry *)to_header; 194 } 195 196 while ((char *)from_entry < from_end && *(__u32 *)from_entry) { 197 ext2fs_swap_ext_attr_entry(to_entry, from_entry); 198 from_entry = EXT2_EXT_ATTR_NEXT(from_entry); 199 to_entry = EXT2_EXT_ATTR_NEXT(to_entry); 200 } 201} 202 203void ext2fs_swap_inode_full(ext2_filsys fs, struct ext2_inode_large *t, 204 struct ext2_inode_large *f, int hostorder, 205 int bufsize) 206{ 207 unsigned i, has_data_blocks, extra_isize, attr_magic; 208 int has_extents = 0; 209 int islnk = 0; 210 __u32 *eaf, *eat; 211 212 if (hostorder && LINUX_S_ISLNK(f->i_mode)) 213 islnk = 1; 214 t->i_mode = ext2fs_swab16(f->i_mode); 215 if (!hostorder && LINUX_S_ISLNK(t->i_mode)) 216 islnk = 1; 217 t->i_uid = ext2fs_swab16(f->i_uid); 218 t->i_size = ext2fs_swab32(f->i_size); 219 t->i_atime = ext2fs_swab32(f->i_atime); 220 t->i_ctime = ext2fs_swab32(f->i_ctime); 221 t->i_mtime = ext2fs_swab32(f->i_mtime); 222 t->i_dtime = ext2fs_swab32(f->i_dtime); 223 t->i_gid = ext2fs_swab16(f->i_gid); 224 t->i_links_count = ext2fs_swab16(f->i_links_count); 225 t->i_file_acl = ext2fs_swab32(f->i_file_acl); 226 if (hostorder) 227 has_data_blocks = ext2fs_inode_data_blocks(fs, 228 (struct ext2_inode *) f); 229 t->i_blocks = ext2fs_swab32(f->i_blocks); 230 if (!hostorder) 231 has_data_blocks = ext2fs_inode_data_blocks(fs, 232 (struct ext2_inode *) t); 233 if (hostorder && (f->i_flags & EXT4_EXTENTS_FL)) 234 has_extents = 1; 235 t->i_flags = ext2fs_swab32(f->i_flags); 236 if (!hostorder && (t->i_flags & EXT4_EXTENTS_FL)) 237 has_extents = 1; 238 t->i_dir_acl = ext2fs_swab32(f->i_dir_acl); 239 /* extent data are swapped on access, not here */ 240 if (!has_extents && (!islnk || has_data_blocks)) { 241 for (i = 0; i < EXT2_N_BLOCKS; i++) 242 t->i_block[i] = ext2fs_swab32(f->i_block[i]); 243 } else if (t != f) { 244 for (i = 0; i < EXT2_N_BLOCKS; i++) 245 t->i_block[i] = f->i_block[i]; 246 } 247 t->i_generation = ext2fs_swab32(f->i_generation); 248 t->i_faddr = ext2fs_swab32(f->i_faddr); 249 250 switch (fs->super->s_creator_os) { 251 case EXT2_OS_LINUX: 252 t->osd1.linux1.l_i_version = 253 ext2fs_swab32(f->osd1.linux1.l_i_version); 254 t->osd2.linux2.l_i_blocks_hi = 255 ext2fs_swab16(f->osd2.linux2.l_i_blocks_hi); 256 t->osd2.linux2.l_i_file_acl_high = 257 ext2fs_swab16(f->osd2.linux2.l_i_file_acl_high); 258 t->osd2.linux2.l_i_uid_high = 259 ext2fs_swab16 (f->osd2.linux2.l_i_uid_high); 260 t->osd2.linux2.l_i_gid_high = 261 ext2fs_swab16 (f->osd2.linux2.l_i_gid_high); 262 t->osd2.linux2.l_i_checksum_lo = 263 ext2fs_swab16(f->osd2.linux2.l_i_checksum_lo); 264 break; 265 case EXT2_OS_HURD: 266 t->osd1.hurd1.h_i_translator = 267 ext2fs_swab32 (f->osd1.hurd1.h_i_translator); 268 t->osd2.hurd2.h_i_frag = f->osd2.hurd2.h_i_frag; 269 t->osd2.hurd2.h_i_fsize = f->osd2.hurd2.h_i_fsize; 270 t->osd2.hurd2.h_i_mode_high = 271 ext2fs_swab16 (f->osd2.hurd2.h_i_mode_high); 272 t->osd2.hurd2.h_i_uid_high = 273 ext2fs_swab16 (f->osd2.hurd2.h_i_uid_high); 274 t->osd2.hurd2.h_i_gid_high = 275 ext2fs_swab16 (f->osd2.hurd2.h_i_gid_high); 276 t->osd2.hurd2.h_i_author = 277 ext2fs_swab32 (f->osd2.hurd2.h_i_author); 278 break; 279 default: 280 break; 281 } 282 283 if (bufsize < (int) (sizeof(struct ext2_inode) + sizeof(__u16))) 284 return; /* no i_extra_isize field */ 285 286 if (hostorder) 287 extra_isize = f->i_extra_isize; 288 t->i_extra_isize = ext2fs_swab16(f->i_extra_isize); 289 if (!hostorder) 290 extra_isize = t->i_extra_isize; 291 if (extra_isize > EXT2_INODE_SIZE(fs->super) - 292 sizeof(struct ext2_inode)) { 293 /* this is error case: i_extra_size is too large */ 294 return; 295 } 296 297 if (extra_isize >= 4) 298 t->i_checksum_hi = ext2fs_swab16(f->i_checksum_hi); 299 if (extra_isize >= 8) 300 t->i_ctime_extra = ext2fs_swab32(f->i_ctime_extra); 301 if (extra_isize >= 12) 302 t->i_mtime_extra = ext2fs_swab32(f->i_mtime_extra); 303 if (extra_isize >= 16) 304 t->i_atime_extra = ext2fs_swab32(f->i_atime_extra); 305 if (extra_isize >= 20) 306 t->i_crtime = ext2fs_swab32(f->i_crtime); 307 if (extra_isize >= 24) 308 t->i_crtime_extra = ext2fs_swab32(f->i_crtime_extra); 309 if (extra_isize >= 28) 310 t->i_version_hi = ext2fs_swab32(f->i_version_hi); 311 312 i = sizeof(struct ext2_inode) + extra_isize + sizeof(__u32); 313 if (bufsize < (int) i) 314 return; /* no space for EA magic */ 315 316 eaf = (__u32 *) (((char *) f) + sizeof(struct ext2_inode) + 317 extra_isize); 318 319 attr_magic = *eaf; 320 if (!hostorder) 321 attr_magic = ext2fs_swab32(attr_magic); 322 323 if (attr_magic != EXT2_EXT_ATTR_MAGIC) 324 return; /* it seems no magic here */ 325 326 eat = (__u32 *) (((char *) t) + sizeof(struct ext2_inode) + 327 extra_isize); 328 *eat = ext2fs_swab32(*eaf); 329 330 /* convert EA(s) */ 331 ext2fs_swap_ext_attr((char *) (eat + 1), (char *) (eaf + 1), 332 bufsize - sizeof(struct ext2_inode) - 333 extra_isize - sizeof(__u32), 0); 334 335} 336 337void ext2fs_swap_inode(ext2_filsys fs, struct ext2_inode *t, 338 struct ext2_inode *f, int hostorder) 339{ 340 ext2fs_swap_inode_full(fs, (struct ext2_inode_large *) t, 341 (struct ext2_inode_large *) f, hostorder, 342 sizeof(struct ext2_inode)); 343} 344 345void ext2fs_swap_mmp(struct mmp_struct *mmp) 346{ 347 mmp->mmp_magic = ext2fs_swab32(mmp->mmp_magic); 348 mmp->mmp_seq = ext2fs_swab32(mmp->mmp_seq); 349 mmp->mmp_time = ext2fs_swab64(mmp->mmp_time); 350 mmp->mmp_check_interval = ext2fs_swab16(mmp->mmp_check_interval); 351} 352 353#endif 354