swapfs.c revision fb6627a3fb4fbcb6904716c7a59e5ef9eb5dfafb
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 24void 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 80void 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 93void ext2fs_swap_ext_attr_header(struct ext2_ext_attr_header *to_header, 94 struct ext2_ext_attr_header *from_header) 95{ 96 int n; 97 98 to_header->h_magic = ext2fs_swab32(from_header->h_magic); 99 to_header->h_blocks = ext2fs_swab32(from_header->h_blocks); 100 to_header->h_refcount = ext2fs_swab32(from_header->h_refcount); 101 to_header->h_hash = ext2fs_swab32(from_header->h_hash); 102 for (n = 0; n < 4; n++) 103 to_header->h_reserved[n] = 104 ext2fs_swab32(from_header->h_reserved[n]); 105} 106 107void ext2fs_swap_ext_attr_entry(struct ext2_ext_attr_entry *to_entry, 108 struct ext2_ext_attr_entry *from_entry) 109{ 110 to_entry->e_value_offs = ext2fs_swab16(from_entry->e_value_offs); 111 to_entry->e_value_block = ext2fs_swab32(from_entry->e_value_block); 112 to_entry->e_value_size = ext2fs_swab32(from_entry->e_value_size); 113 to_entry->e_hash = ext2fs_swab32(from_entry->e_hash); 114} 115 116void ext2fs_swap_ext_attr(char *to, char *from, int bufsize, int has_header) 117{ 118 struct ext2_ext_attr_header *from_header = 119 (struct ext2_ext_attr_header *)from; 120 struct ext2_ext_attr_header *to_header = 121 (struct ext2_ext_attr_header *)to; 122 struct ext2_ext_attr_entry *from_entry, *to_entry; 123 char *from_end = (char *)from_header + bufsize; 124 125 if (to_header != from_header) 126 memcpy(to_header, from_header, bufsize); 127 128 if (has_header) { 129 ext2fs_swap_ext_attr_header(to_header, from_header); 130 131 from_entry = (struct ext2_ext_attr_entry *)(from_header+1); 132 to_entry = (struct ext2_ext_attr_entry *)(to_header+1); 133 } else { 134 from_entry = (struct ext2_ext_attr_entry *)from_header; 135 to_entry = (struct ext2_ext_attr_entry *)to_header; 136 } 137 138 while ((char *)from_entry < from_end && *(__u32 *)from_entry) { 139 ext2fs_swap_ext_attr_entry(to_entry, from_entry); 140 from_entry = EXT2_EXT_ATTR_NEXT(from_entry); 141 to_entry = EXT2_EXT_ATTR_NEXT(to_entry); 142 } 143} 144 145void ext2fs_swap_inode_full(ext2_filsys fs, struct ext2_inode_large *t, 146 struct ext2_inode_large *f, int hostorder, 147 int bufsize) 148{ 149 unsigned i, has_data_blocks, extra_isize, attr_magic; 150 int has_extents = 0; 151 int islnk = 0; 152 __u32 *eaf, *eat; 153 154 if (hostorder && LINUX_S_ISLNK(f->i_mode)) 155 islnk = 1; 156 t->i_mode = ext2fs_swab16(f->i_mode); 157 if (!hostorder && LINUX_S_ISLNK(t->i_mode)) 158 islnk = 1; 159 t->i_uid = ext2fs_swab16(f->i_uid); 160 t->i_size = ext2fs_swab32(f->i_size); 161 t->i_atime = ext2fs_swab32(f->i_atime); 162 t->i_ctime = ext2fs_swab32(f->i_ctime); 163 t->i_mtime = ext2fs_swab32(f->i_mtime); 164 t->i_dtime = ext2fs_swab32(f->i_dtime); 165 t->i_gid = ext2fs_swab16(f->i_gid); 166 t->i_links_count = ext2fs_swab16(f->i_links_count); 167 t->i_file_acl = ext2fs_swab32(f->i_file_acl); 168 if (hostorder) 169 has_data_blocks = ext2fs_inode_data_blocks(fs, 170 (struct ext2_inode *) f); 171 t->i_blocks = ext2fs_swab32(f->i_blocks); 172 if (!hostorder) 173 has_data_blocks = ext2fs_inode_data_blocks(fs, 174 (struct ext2_inode *) t); 175 if (hostorder && (f->i_flags & EXT4_EXTENTS_FL)) 176 has_extents = 1; 177 t->i_flags = ext2fs_swab32(f->i_flags); 178 if (!hostorder && (t->i_flags & EXT4_EXTENTS_FL)) 179 has_extents = 1; 180 t->i_dir_acl = ext2fs_swab32(f->i_dir_acl); 181 /* extent data are swapped on access, not here */ 182 if (!has_extents && (!islnk || has_data_blocks)) { 183 for (i = 0; i < EXT2_N_BLOCKS; i++) 184 t->i_block[i] = ext2fs_swab32(f->i_block[i]); 185 } else if (t != f) { 186 for (i = 0; i < EXT2_N_BLOCKS; i++) 187 t->i_block[i] = f->i_block[i]; 188 } 189 t->i_generation = ext2fs_swab32(f->i_generation); 190 t->i_faddr = ext2fs_swab32(f->i_faddr); 191 192 switch (fs->super->s_creator_os) { 193 case EXT2_OS_LINUX: 194 t->osd1.linux1.l_i_version = 195 ext2fs_swab32(f->osd1.linux1.l_i_version); 196 t->osd2.linux2.l_i_blocks_hi = 197 ext2fs_swab16(f->osd2.linux2.l_i_blocks_hi); 198 t->osd2.linux2.i_pad1 = ext2fs_swab16(f->osd2.linux2.i_pad1); 199 t->osd2.linux2.l_i_uid_high = 200 ext2fs_swab16 (f->osd2.linux2.l_i_uid_high); 201 t->osd2.linux2.l_i_gid_high = 202 ext2fs_swab16 (f->osd2.linux2.l_i_gid_high); 203 t->osd2.linux2.l_i_reserved2 = 204 ext2fs_swab32(f->osd2.linux2.l_i_reserved2); 205 break; 206 case EXT2_OS_HURD: 207 t->osd1.hurd1.h_i_translator = 208 ext2fs_swab32 (f->osd1.hurd1.h_i_translator); 209 t->osd2.hurd2.h_i_frag = f->osd2.hurd2.h_i_frag; 210 t->osd2.hurd2.h_i_fsize = f->osd2.hurd2.h_i_fsize; 211 t->osd2.hurd2.h_i_mode_high = 212 ext2fs_swab16 (f->osd2.hurd2.h_i_mode_high); 213 t->osd2.hurd2.h_i_uid_high = 214 ext2fs_swab16 (f->osd2.hurd2.h_i_uid_high); 215 t->osd2.hurd2.h_i_gid_high = 216 ext2fs_swab16 (f->osd2.hurd2.h_i_gid_high); 217 t->osd2.hurd2.h_i_author = 218 ext2fs_swab32 (f->osd2.hurd2.h_i_author); 219 break; 220 default: 221 break; 222 } 223 224 if (bufsize < (int) (sizeof(struct ext2_inode) + sizeof(__u16))) 225 return; /* no i_extra_isize field */ 226 227 if (hostorder) 228 extra_isize = f->i_extra_isize; 229 t->i_extra_isize = ext2fs_swab16(f->i_extra_isize); 230 if (!hostorder) 231 extra_isize = t->i_extra_isize; 232 if (extra_isize > EXT2_INODE_SIZE(fs->super) - 233 sizeof(struct ext2_inode)) { 234 /* this is error case: i_extra_size is too large */ 235 return; 236 } 237 238 i = sizeof(struct ext2_inode) + extra_isize + sizeof(__u32); 239 if (bufsize < (int) i) 240 return; /* no space for EA magic */ 241 242 eaf = (__u32 *) (((char *) f) + sizeof(struct ext2_inode) + 243 extra_isize); 244 245 attr_magic = *eaf; 246 if (!hostorder) 247 attr_magic = ext2fs_swab32(attr_magic); 248 249 if (attr_magic != EXT2_EXT_ATTR_MAGIC) 250 return; /* it seems no magic here */ 251 252 eat = (__u32 *) (((char *) t) + sizeof(struct ext2_inode) + 253 extra_isize); 254 *eat = ext2fs_swab32(*eaf); 255 256 /* convert EA(s) */ 257 ext2fs_swap_ext_attr((char *) (eat + 1), (char *) (eaf + 1), 258 bufsize - sizeof(struct ext2_inode) - 259 extra_isize - sizeof(__u32), 0); 260 261} 262 263void ext2fs_swap_inode(ext2_filsys fs, struct ext2_inode *t, 264 struct ext2_inode *f, int hostorder) 265{ 266 ext2fs_swap_inode_full(fs, (struct ext2_inode_large *) t, 267 (struct ext2_inode_large *) f, hostorder, 268 sizeof(struct ext2_inode)); 269} 270 271#endif 272