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         for (i=0; i < 4; i++)
  74                 sb->s_hash_seed[i] = ext2fs_swab32(sb->s_hash_seed[i]);
  75         for (i=0; i < 17; i++)
  76                 sb->s_jnl_blocks[i] = ext2fs_swab32(sb->s_jnl_blocks[i]);
  77
  78 }
  79
  80 void ext2fs_swap_group_desc(struct ext2_group_desc *gdp)
  81 {
  82         gdp->bg_block_bitmap = ext2fs_swab32(gdp->bg_block_bitmap);
  83         gdp->bg_inode_bitmap = ext2fs_swab32(gdp->bg_inode_bitmap);
  84         gdp->bg_inode_table = ext2fs_swab32(gdp->bg_inode_table);
  85         gdp->bg_free_blocks_count = ext2fs_swab16(gdp->bg_free_blocks_count);
  86         gdp->bg_free_inodes_count = ext2fs_swab16(gdp->bg_free_inodes_count);
  87         gdp->bg_used_dirs_count = ext2fs_swab16(gdp->bg_used_dirs_count);
  88         gdp->bg_flags = ext2fs_swab16(gdp->bg_flags);
  89         gdp->bg_itable_unused = ext2fs_swab16(gdp->bg_itable_unused);
  90         gdp->bg_checksum = ext2fs_swab16(gdp->bg_checksum);
  91 }
  92
  93 void ext2fs_swap_ext_attr(char *to, char *from, int bufsize, int has_header)
  94 {
  95         struct ext2_ext_attr_header *from_header =
  96                 (struct ext2_ext_attr_header *)from;
  97         struct ext2_ext_attr_header *to_header =
  98                 (struct ext2_ext_attr_header *)to;
  99         struct ext2_ext_attr_entry *from_entry, *to_entry;
 100         char *from_end = (char *)from_header + bufsize;
 101         int n;
 102
 103         if (to_header != from_header)
 104                 memcpy(to_header, from_header, bufsize);
 105
 106         from_entry = (struct ext2_ext_attr_entry *)from_header;
 107         to_entry   = (struct ext2_ext_attr_entry *)to_header;
 108
 109         if (has_header) {
 110                 to_header->h_magic    = ext2fs_swab32(from_header->h_magic);
 111                 to_header->h_blocks   = ext2fs_swab32(from_header->h_blocks);
 112                 to_header->h_refcount = ext2fs_swab32(from_header->h_refcount);
 113                 for (n=0; n<4; n++)
 114                         to_header->h_reserved[n] =
 115                                 ext2fs_swab32(from_header->h_reserved[n]);
 116                 from_entry = (struct ext2_ext_attr_entry *)(from_header+1);
 117                 to_entry   = (struct ext2_ext_attr_entry *)(to_header+1);
 118         }
 119
 120         while ((char *)from_entry < from_end && *(__u32 *)from_entry) {
 121                 to_entry->e_value_offs  =
 122                         ext2fs_swab16(from_entry->e_value_offs);
 123                 to_entry->e_value_block =
 124                         ext2fs_swab32(from_entry->e_value_block);
 125                 to_entry->e_value_size  =
 126                         ext2fs_swab32(from_entry->e_value_size);
 127                 from_entry = EXT2_EXT_ATTR_NEXT(from_entry);
 128                 to_entry   = EXT2_EXT_ATTR_NEXT(to_entry);
 129         }
 130 }
 131
 132 void ext2fs_swap_inode_full(ext2_filsys fs, struct ext2_inode_large *t,
 133                             struct ext2_inode_large *f, int hostorder,
 134                             int bufsize)
 135 {
 136         unsigned i, has_data_blocks, extra_isize;
 137         int islnk = 0;
 138         __u32 *eaf, *eat;
 139
 140         if (hostorder && LINUX_S_ISLNK(f->i_mode))
 141                 islnk = 1;
 142         t->i_mode = ext2fs_swab16(f->i_mode);
 143         if (!hostorder && LINUX_S_ISLNK(t->i_mode))
 144                 islnk = 1;
 145         t->i_uid = ext2fs_swab16(f->i_uid);
 146         t->i_size = ext2fs_swab32(f->i_size);
 147         t->i_atime = ext2fs_swab32(f->i_atime);
 148         t->i_ctime = ext2fs_swab32(f->i_ctime);
 149         t->i_mtime = ext2fs_swab32(f->i_mtime);
 150         t->i_dtime = ext2fs_swab32(f->i_dtime);
 151         t->i_gid = ext2fs_swab16(f->i_gid);
 152         t->i_links_count = ext2fs_swab16(f->i_links_count);
 153         t->i_file_acl = ext2fs_swab32(f->i_file_acl);
 154         if (hostorder)
 155                 has_data_blocks = ext2fs_inode_data_blocks(fs,
 156                                            (struct ext2_inode *) f);
 157         t->i_blocks = ext2fs_swab32(f->i_blocks);
 158         if (!hostorder)
 159                 has_data_blocks = ext2fs_inode_data_blocks(fs,
 160                                            (struct ext2_inode *) t);
 161         t->i_flags = ext2fs_swab32(f->i_flags);
 162         t->i_dir_acl = ext2fs_swab32(f->i_dir_acl);
 163         if (!islnk || has_data_blocks ) {
 164                 for (i = 0; i < EXT2_N_BLOCKS; i++)
 165                         t->i_block[i] = ext2fs_swab32(f->i_block[i]);
 166         } else if (t != f) {
 167                 for (i = 0; i < EXT2_N_BLOCKS; i++)
 168                         t->i_block[i] = f->i_block[i];
 169         }
 170         t->i_generation = ext2fs_swab32(f->i_generation);
 171         t->i_faddr = ext2fs_swab32(f->i_faddr);
 172
 173         switch (fs->super->s_creator_os) {
 174         case EXT2_OS_LINUX:
 175                 t->osd1.linux1.l_i_version =
 176                         ext2fs_swab32(f->osd1.linux1.l_i_version);
 177                 t->osd2.linux2.l_i_blocks_hi =
 178                         ext2fs_swab16(f->osd2.linux2.l_i_blocks_hi);
 179                 t->osd2.linux2.i_pad1 = ext2fs_swab16(f->osd2.linux2.i_pad1);
 180                 t->osd2.linux2.l_i_uid_high =
 181                   ext2fs_swab16 (f->osd2.linux2.l_i_uid_high);
 182                 t->osd2.linux2.l_i_gid_high =
 183                   ext2fs_swab16 (f->osd2.linux2.l_i_gid_high);
 184                 t->osd2.linux2.l_i_reserved2 =
 185                         ext2fs_swab32(f->osd2.linux2.l_i_reserved2);
 186                 break;
 187         case EXT2_OS_HURD:
 188                 t->osd1.hurd1.h_i_translator =
 189                   ext2fs_swab32 (f->osd1.hurd1.h_i_translator);
 190                 t->osd2.hurd2.h_i_frag = f->osd2.hurd2.h_i_frag;
 191                 t->osd2.hurd2.h_i_fsize = f->osd2.hurd2.h_i_fsize;
 192                 t->osd2.hurd2.h_i_mode_high =
 193                   ext2fs_swab16 (f->osd2.hurd2.h_i_mode_high);
 194                 t->osd2.hurd2.h_i_uid_high =
 195                   ext2fs_swab16 (f->osd2.hurd2.h_i_uid_high);
 196                 t->osd2.hurd2.h_i_gid_high =
 197                   ext2fs_swab16 (f->osd2.hurd2.h_i_gid_high);
 198                 t->osd2.hurd2.h_i_author =
 199                   ext2fs_swab32 (f->osd2.hurd2.h_i_author);
 200                 break;
 201         default:
 202                 break;
 203         }
 204
 205         if (bufsize < (int) (sizeof(struct ext2_inode) + sizeof(__u16)))
 206                 return; /* no i_extra_isize field */
 207
 208         if (hostorder)
 209                 extra_isize = f->i_extra_isize;
 210         t->i_extra_isize = ext2fs_swab16(f->i_extra_isize);
 211         if (!hostorder)
 212                 extra_isize = t->i_extra_isize;
 213         if (extra_isize > EXT2_INODE_SIZE(fs->super) -
 214                                 sizeof(struct ext2_inode)) {
 215                 /* this is error case: i_extra_size is too large */
 216                 return;
 217         }
 218
 219         i = sizeof(struct ext2_inode) + extra_isize + sizeof(__u32);
 220         if (bufsize < (int) i)
 221                 return; /* no space for EA magic */
 222
 223         eaf = (__u32 *) (((char *) f) + sizeof(struct ext2_inode) +
 224                                         extra_isize);
 225
 226         if (ext2fs_swab32(*eaf) != EXT2_EXT_ATTR_MAGIC)
 227                 return; /* it seems no magic here */
 228
 229         eat = (__u32 *) (((char *) t) + sizeof(struct ext2_inode) +
 230                                         extra_isize);
 231         *eat = ext2fs_swab32(*eaf);
 232
 233         /* convert EA(s) */
 234         ext2fs_swap_ext_attr((char *) (eat + 1), (char *) (eaf + 1),
 235                              bufsize - sizeof(struct ext2_inode) -
 236                              extra_isize - sizeof(__u32), 0);
 237
 238 }
 239
 240 void ext2fs_swap_inode(ext2_filsys fs, struct ext2_inode *t,
 241                        struct ext2_inode *f, int hostorder)
 242 {
 243         ext2fs_swap_inode_full(fs, (struct ext2_inode_large *) t,
 244                                 (struct ext2_inode_large *) f, hostorder,
 245                                 sizeof(struct ext2_inode));
 246 }
 247
 248 #endif