lib/ext2fs/swapfs.c

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