lib/ext2fs/ext_attr.c

   1 /*
   2  * ext_attr.c --- extended attribute blocks
   3  *
   4  * Copyright (C) 2001 Andreas Gruenbacher, <a.gruenbacher@computer.org>
   5  *
   6  * Copyright (C) 2002 Theodore Ts'o.
   7  *
   8  * %Begin-Header%
   9  * This file may be redistributed under the terms of the GNU Library
  10  * General Public License, version 2.
  11  * %End-Header%
  12  */
  13
  14 #include "config.h"
  15 #include <stdio.h>
  16 #if HAVE_UNISTD_H
  17 #include <unistd.h>
  18 #endif
  19 #include <string.h>
  20 #include <time.h>
  21
  22 #include "ext2_fs.h"
  23 #include "ext2_ext_attr.h"
  24 #include "ext4_acl.h"
  25
  26 #include "ext2fs.h"
  27
  28 static errcode_t read_ea_inode_hash(ext2_filsys fs, ext2_ino_t ino, __u32 *hash)
  29 {
  30         struct ext2_inode inode;
  31         errcode_t retval;
  32
  33         retval = ext2fs_read_inode(fs, ino, &inode);
  34         if (retval)
  35                 return retval;
  36         *hash = ext2fs_get_ea_inode_hash(&inode);
  37         return 0;
  38 }
  39
  40 #define NAME_HASH_SHIFT 5
  41 #define VALUE_HASH_SHIFT 16
  42
  43 /*
  44  * ext2_xattr_hash_entry()
  45  *
  46  * Compute the hash of an extended attribute.
  47  */
  48 __u32 ext2fs_ext_attr_hash_entry(struct ext2_ext_attr_entry *entry, void *data)
  49 {
  50         __u32 hash = 0;
  51         char *name = ((char *) entry) + sizeof(struct ext2_ext_attr_entry);
  52         int n;
  53
  54         for (n = 0; n < entry->e_name_len; n++) {
  55                 hash = (hash << NAME_HASH_SHIFT) ^
  56                        (hash >> (8*sizeof(hash) - NAME_HASH_SHIFT)) ^
  57                        *name++;
  58         }
  59
  60         /* The hash needs to be calculated on the data in little-endian. */
  61         if (entry->e_value_inum == 0 && entry->e_value_size != 0) {
  62                 __u32 *value = (__u32 *)data;
  63                 for (n = (entry->e_value_size + EXT2_EXT_ATTR_ROUND) >>
  64                          EXT2_EXT_ATTR_PAD_BITS; n; n--) {
  65                         hash = (hash << VALUE_HASH_SHIFT) ^
  66                                (hash >> (8*sizeof(hash) - VALUE_HASH_SHIFT)) ^
  67                                ext2fs_le32_to_cpu(*value++);
  68                 }
  69         }
  70
  71         return hash;
  72 }
  73
  74 /*
  75  * ext2fs_ext_attr_hash_entry2()
  76  *
  77  * Compute the hash of an extended attribute.
  78  * This version of the function supports hashing entries that reference
  79  * external inodes (ea_inode feature).
  80  */
  81 errcode_t ext2fs_ext_attr_hash_entry2(ext2_filsys fs,
  82                                       struct ext2_ext_attr_entry *entry,
  83                                       void *data, __u32 *hash)
  84 {
  85         *hash = ext2fs_ext_attr_hash_entry(entry, data);
  86
  87         if (entry->e_value_inum) {
  88                 __u32 ea_inode_hash;
  89                 errcode_t retval;
  90
  91                 retval = read_ea_inode_hash(fs, entry->e_value_inum,
  92                                             &ea_inode_hash);
  93                 if (retval)
  94                         return retval;
  95
  96                 *hash = (*hash << VALUE_HASH_SHIFT) ^
  97                         (*hash >> (8*sizeof(*hash) - VALUE_HASH_SHIFT)) ^
  98                         ea_inode_hash;
  99         }
 100         return 0;
 101 }
 102
 103 #undef NAME_HASH_SHIFT
 104 #undef VALUE_HASH_SHIFT
 105
 106 #define BLOCK_HASH_SHIFT 16
 107
 108 /* Mirrors ext4_xattr_rehash() implementation in kernel. */
 109 void ext2fs_ext_attr_block_rehash(struct ext2_ext_attr_header *header,
 110                                   struct ext2_ext_attr_entry *end)
 111 {
 112         struct ext2_ext_attr_entry *here;
 113         __u32 hash = 0;
 114
 115         here = (struct ext2_ext_attr_entry *)(header+1);
 116         while (here < end && !EXT2_EXT_IS_LAST_ENTRY(here)) {
 117                 if (!here->e_hash) {
 118                         /* Block is not shared if an entry's hash value == 0 */
 119                         hash = 0;
 120                         break;
 121                 }
 122                 hash = (hash << BLOCK_HASH_SHIFT) ^
 123                        (hash >> (8*sizeof(hash) - BLOCK_HASH_SHIFT)) ^
 124                        here->e_hash;
 125                 here = EXT2_EXT_ATTR_NEXT(here);
 126         }
 127         header->h_hash = hash;
 128 }
 129
 130 #undef BLOCK_HASH_SHIFT
 131
 132 __u32 ext2fs_get_ea_inode_hash(struct ext2_inode *inode)
 133 {
 134         return inode->i_atime;
 135 }
 136
 137 void ext2fs_set_ea_inode_hash(struct ext2_inode *inode, __u32 hash)
 138 {
 139         inode->i_atime = hash;
 140 }
 141
 142 static errcode_t check_ext_attr_header(struct ext2_ext_attr_header *header)
 143 {
 144         if ((header->h_magic != EXT2_EXT_ATTR_MAGIC_v1 &&
 145              header->h_magic != EXT2_EXT_ATTR_MAGIC) ||
 146             header->h_blocks != 1)
 147                 return EXT2_ET_BAD_EA_HEADER;
 148
 149         return 0;
 150 }
 151
 152 errcode_t ext2fs_read_ext_attr3(ext2_filsys fs, blk64_t block, void *buf,
 153                                 ext2_ino_t inum)
 154 {
 155         int             csum_failed = 0;
 156         errcode_t       retval;
 157
 158         retval = io_channel_read_blk64(fs->io, block, 1, buf);
 159         if (retval)
 160                 return retval;
 161
 162         if (!(fs->flags & EXT2_FLAG_IGNORE_CSUM_ERRORS) &&
 163             !ext2fs_ext_attr_block_csum_verify(fs, inum, block, buf))
 164                 csum_failed = 1;
 165
 166 #ifdef WORDS_BIGENDIAN
 167         ext2fs_swap_ext_attr(buf, buf, fs->blocksize, 1);
 168 #endif
 169
 170         retval = check_ext_attr_header(buf);
 171         if (retval == 0 && csum_failed)
 172                 retval = EXT2_ET_EXT_ATTR_CSUM_INVALID;
 173
 174         return retval;
 175 }
 176
 177 errcode_t ext2fs_read_ext_attr2(ext2_filsys fs, blk64_t block, void *buf)
 178 {
 179         return ext2fs_read_ext_attr3(fs, block, buf, 0);
 180 }
 181
 182 errcode_t ext2fs_read_ext_attr(ext2_filsys fs, blk_t block, void *buf)
 183 {
 184         return ext2fs_read_ext_attr2(fs, block, buf);
 185 }
 186
 187 errcode_t ext2fs_write_ext_attr3(ext2_filsys fs, blk64_t block, void *inbuf,
 188                                  ext2_ino_t inum)
 189 {
 190         errcode_t       retval;
 191         char            *write_buf;
 192
 193 #ifdef WORDS_BIGENDIAN
 194         retval = ext2fs_get_mem(fs->blocksize, &write_buf);
 195         if (retval)
 196                 return retval;
 197         ext2fs_swap_ext_attr(write_buf, inbuf, fs->blocksize, 1);
 198 #else
 199         write_buf = (char *) inbuf;
 200 #endif
 201
 202         retval = ext2fs_ext_attr_block_csum_set(fs, inum, block,
 203                         (struct ext2_ext_attr_header *)write_buf);
 204         if (retval)
 205                 return retval;
 206
 207         retval = io_channel_write_blk64(fs->io, block, 1, write_buf);
 208 #ifdef WORDS_BIGENDIAN
 209         ext2fs_free_mem(&write_buf);
 210 #endif
 211         if (!retval)
 212                 ext2fs_mark_changed(fs);
 213         return retval;
 214 }
 215
 216 errcode_t ext2fs_write_ext_attr2(ext2_filsys fs, blk64_t block, void *inbuf)
 217 {
 218         return ext2fs_write_ext_attr3(fs, block, inbuf, 0);
 219 }
 220
 221 errcode_t ext2fs_write_ext_attr(ext2_filsys fs, blk_t block, void *inbuf)
 222 {
 223         return ext2fs_write_ext_attr2(fs, block, inbuf);
 224 }
 225
 226 /*
 227  * This function adjusts the reference count of the EA block.
 228  */
 229 errcode_t ext2fs_adjust_ea_refcount3(ext2_filsys fs, blk64_t blk,
 230                                     char *block_buf, int adjust,
 231                                     __u32 *newcount, ext2_ino_t inum)
 232 {
 233         errcode_t       retval;
 234         struct ext2_ext_attr_header *header;
 235         char    *buf = 0;
 236
 237         if ((blk >= ext2fs_blocks_count(fs->super)) ||
 238             (blk < fs->super->s_first_data_block))
 239                 return EXT2_ET_BAD_EA_BLOCK_NUM;
 240
 241         if (!block_buf) {
 242                 retval = ext2fs_get_mem(fs->blocksize, &buf);
 243                 if (retval)
 244                         return retval;
 245                 block_buf = buf;
 246         }
 247
 248         retval = ext2fs_read_ext_attr3(fs, blk, block_buf, inum);
 249         if (retval)
 250                 goto errout;
 251
 252         header = (struct ext2_ext_attr_header *) block_buf;
 253         header->h_refcount += adjust;
 254         if (newcount)
 255                 *newcount = header->h_refcount;
 256
 257         retval = ext2fs_write_ext_attr3(fs, blk, block_buf, inum);
 258         if (retval)
 259                 goto errout;
 260
 261 errout:
 262         if (buf)
 263                 ext2fs_free_mem(&buf);
 264         return retval;
 265 }
 266
 267 errcode_t ext2fs_adjust_ea_refcount2(ext2_filsys fs, blk64_t blk,
 268                                     char *block_buf, int adjust,
 269                                     __u32 *newcount)
 270 {
 271         return ext2fs_adjust_ea_refcount3(fs, blk, block_buf, adjust,
 272                                           newcount, 0);
 273 }
 274
 275 errcode_t ext2fs_adjust_ea_refcount(ext2_filsys fs, blk_t blk,
 276                                         char *block_buf, int adjust,
 277                                         __u32 *newcount)
 278 {
 279         return ext2fs_adjust_ea_refcount2(fs, blk, block_buf, adjust,
 280                                           newcount);
 281 }
 282
 283 /* Manipulate the contents of extended attribute regions */
 284 struct ext2_xattr {
 285         char *name;
 286         void *value;
 287         size_t value_len;
 288 };
 289
 290 struct ext2_xattr_handle {
 291         errcode_t magic;
 292         ext2_filsys fs;
 293         struct ext2_xattr *attrs;
 294         size_t capacity, count;
 295         ext2_ino_t ino;
 296         unsigned int flags;
 297         int dirty;
 298 };
 299
 300 static errcode_t ext2fs_xattrs_expand(struct ext2_xattr_handle *h,
 301                                       unsigned int expandby)
 302 {
 303         struct ext2_xattr *new_attrs;
 304         errcode_t err;
 305
 306         err = ext2fs_get_arrayzero(h->capacity + expandby,
 307                                    sizeof(struct ext2_xattr), &new_attrs);
 308         if (err)
 309                 return err;
 310
 311         memcpy(new_attrs, h->attrs, h->capacity * sizeof(struct ext2_xattr));
 312         ext2fs_free_mem(&h->attrs);
 313         h->capacity += expandby;
 314         h->attrs = new_attrs;
 315
 316         return 0;
 317 }
 318
 319 struct ea_name_index {
 320         int index;
 321         const char *name;
 322 };
 323
 324 /* Keep these names sorted in order of decreasing specificity. */
 325 static struct ea_name_index ea_names[] = {
 326         {3, "system.posix_acl_default"},
 327         {2, "system.posix_acl_access"},
 328         {8, "system.richacl"},
 329         {6, "security."},
 330         {4, "trusted."},
 331         {7, "system."},
 332         {1, "user."},
 333         {0, NULL},
 334 };
 335
 336 static int find_ea_index(char *fullname, char **name, int *index);
 337
 338 /* Pull inlinedata to the front. */
 339 static int attr_compare(const void *a, const void *b)
 340 {
 341         const struct ext2_xattr *xa = a, *xb = b;
 342         char *xa_suffix, *xb_suffix;
 343         int xa_idx, xb_idx;
 344         int cmp;
 345
 346         if (!strcmp(xa->name, "system.data"))
 347                 return -1;
 348         else if (!strcmp(xb->name, "system.data"))
 349                 return +1;
 350
 351         /*
 352          * Duplicate the kernel's sorting algorithm because xattr blocks
 353          * require sorted keys.
 354          */
 355         xa_suffix = xa->name;
 356         xb_suffix = xb->name;
 357         xa_idx = xb_idx = 0;
 358         find_ea_index(xa->name, &xa_suffix, &xa_idx);
 359         find_ea_index(xb->name, &xb_suffix, &xb_idx);
 360         cmp = xa_idx - xb_idx;
 361         if (cmp)
 362                 return cmp;
 363         cmp = strlen(xa_suffix) - strlen(xb_suffix);
 364         if (cmp)
 365                 return cmp;
 366         cmp = strcmp(xa_suffix, xb_suffix);
 367         return cmp;
 368 }
 369
 370 static const char *find_ea_prefix(int index)
 371 {
 372         struct ea_name_index *e;
 373
 374         for (e = ea_names; e->name; e++)
 375                 if (e->index == index)
 376                         return e->name;
 377
 378         return NULL;
 379 }
 380
 381 static int find_ea_index(char *fullname, char **name, int *index)
 382 {
 383         struct ea_name_index *e;
 384
 385         for (e = ea_names; e->name; e++) {
 386                 if (strncmp(fullname, e->name, strlen(e->name)) == 0) {
 387                         *name = (char *)fullname + strlen(e->name);
 388                         *index = e->index;
 389                         return 1;
 390                 }
 391         }
 392         return 0;
 393 }
 394
 395 errcode_t ext2fs_free_ext_attr(ext2_filsys fs, ext2_ino_t ino,
 396                                struct ext2_inode_large *inode)
 397 {
 398         struct ext2_ext_attr_header *header;
 399         void *block_buf = NULL;
 400         blk64_t blk;
 401         errcode_t err;
 402         struct ext2_inode_large i;
 403
 404         /* Read inode? */
 405         if (inode == NULL) {
 406                 err = ext2fs_read_inode_full(fs, ino, (struct ext2_inode *)&i,
 407                                              sizeof(struct ext2_inode_large));
 408                 if (err)
 409                         return err;
 410                 inode = &i;
 411         }
 412
 413         /* Do we already have an EA block? */
 414         blk = ext2fs_file_acl_block(fs, (struct ext2_inode *)inode);
 415         if (blk == 0)
 416                 return 0;
 417
 418         /* Find block, zero it, write back */
 419         if ((blk < fs->super->s_first_data_block) ||
 420             (blk >= ext2fs_blocks_count(fs->super))) {
 421                 err = EXT2_ET_BAD_EA_BLOCK_NUM;
 422                 goto out;
 423         }
 424
 425         err = ext2fs_get_mem(fs->blocksize, &block_buf);
 426         if (err)
 427                 goto out;
 428
 429         err = ext2fs_read_ext_attr3(fs, blk, block_buf, ino);
 430         if (err)
 431                 goto out2;
 432
 433         /* We only know how to deal with v2 EA blocks */
 434         header = (struct ext2_ext_attr_header *) block_buf;
 435         if (header->h_magic != EXT2_EXT_ATTR_MAGIC) {
 436                 err = EXT2_ET_BAD_EA_HEADER;
 437                 goto out2;
 438         }
 439
 440         header->h_refcount--;
 441         err = ext2fs_write_ext_attr3(fs, blk, block_buf, ino);
 442         if (err)
 443                 goto out2;
 444
 445         /* Erase link to block */
 446         ext2fs_file_acl_block_set(fs, (struct ext2_inode *)inode, 0);
 447         if (header->h_refcount == 0)
 448                 ext2fs_block_alloc_stats2(fs, blk, -1);
 449         err = ext2fs_iblk_sub_blocks(fs, (struct ext2_inode *)inode, 1);
 450         if (err)
 451                 goto out2;
 452
 453         /* Write inode? */
 454         if (inode == &i) {
 455                 err = ext2fs_write_inode_full(fs, ino, (struct ext2_inode *)&i,
 456                                               sizeof(struct ext2_inode_large));
 457                 if (err)
 458                         goto out2;
 459         }
 460
 461 out2:
 462         ext2fs_free_mem(&block_buf);
 463 out:
 464         return err;
 465 }
 466
 467 static errcode_t prep_ea_block_for_write(ext2_filsys fs, ext2_ino_t ino,
 468                                          struct ext2_inode_large *inode)
 469 {
 470         struct ext2_ext_attr_header *header;
 471         void *block_buf = NULL;
 472         blk64_t blk, goal;
 473         errcode_t err;
 474
 475         /* Do we already have an EA block? */
 476         blk = ext2fs_file_acl_block(fs, (struct ext2_inode *)inode);
 477         if (blk != 0) {
 478                 if ((blk < fs->super->s_first_data_block) ||
 479                     (blk >= ext2fs_blocks_count(fs->super))) {
 480                         err = EXT2_ET_BAD_EA_BLOCK_NUM;
 481                         goto out;
 482                 }
 483
 484                 err = ext2fs_get_mem(fs->blocksize, &block_buf);
 485                 if (err)
 486                         goto out;
 487
 488                 err = ext2fs_read_ext_attr3(fs, blk, block_buf, ino);
 489                 if (err)
 490                         goto out2;
 491
 492                 /* We only know how to deal with v2 EA blocks */
 493                 header = (struct ext2_ext_attr_header *) block_buf;
 494                 if (header->h_magic != EXT2_EXT_ATTR_MAGIC) {
 495                         err = EXT2_ET_BAD_EA_HEADER;
 496                         goto out2;
 497                 }
 498
 499                 /* Single-user block.  We're done here. */
 500                 if (header->h_refcount == 1)
 501                         goto out2;
 502
 503                 /* We need to CoW the block. */
 504                 header->h_refcount--;
 505                 err = ext2fs_write_ext_attr3(fs, blk, block_buf, ino);
 506                 if (err)
 507                         goto out2;
 508         } else {
 509                 /* No block, we must increment i_blocks */
 510                 err = ext2fs_iblk_add_blocks(fs, (struct ext2_inode *)inode,
 511                                              1);
 512                 if (err)
 513                         goto out;
 514         }
 515
 516         /* Allocate a block */
 517         goal = ext2fs_find_inode_goal(fs, ino, (struct ext2_inode *)inode, 0);
 518         err = ext2fs_alloc_block2(fs, goal, NULL, &blk);
 519         if (err)
 520                 goto out2;
 521         ext2fs_file_acl_block_set(fs, (struct ext2_inode *)inode, blk);
 522 out2:
 523         if (block_buf)
 524                 ext2fs_free_mem(&block_buf);
 525 out:
 526         return err;
 527 }
 528
 529
 530 static inline int
 531 posix_acl_xattr_count(size_t size)
 532 {
 533         if (size < sizeof(posix_acl_xattr_header))
 534                 return -1;
 535         size -= sizeof(posix_acl_xattr_header);
 536         if (size % sizeof(posix_acl_xattr_entry))
 537                 return -1;
 538         return size / sizeof(posix_acl_xattr_entry);
 539 }
 540
 541 /*
 542  * The lgetxattr function returns data formatted in the POSIX extended
 543  * attribute format.  The on-disk format uses a more compact encoding.
 544  * See the ext4_acl_to_disk in fs/ext4/acl.c.
 545  */
 546 static errcode_t convert_posix_acl_to_disk_buffer(const void *value, size_t size,
 547                                                   void *out_buf, size_t *size_out)
 548 {
 549         posix_acl_xattr_header *header = (posix_acl_xattr_header*) value;
 550         posix_acl_xattr_entry *entry = (posix_acl_xattr_entry *)(header+1), *end;
 551         ext4_acl_header *ext_acl;
 552         size_t s;
 553         void *e;
 554
 555         int count;
 556
 557         if (!value)
 558                 return EINVAL;
 559         if (size < sizeof(posix_acl_xattr_header))
 560                 return ENOMEM;
 561         if (header->a_version != ext2fs_cpu_to_le32(POSIX_ACL_XATTR_VERSION))
 562                 return EINVAL;
 563
 564         count = posix_acl_xattr_count(size);
 565         ext_acl = out_buf;
 566         ext_acl->a_version = ext2fs_cpu_to_le32(EXT4_ACL_VERSION);
 567
 568         if (count <= 0)
 569                 return EINVAL;
 570
 571         e = (char *) out_buf + sizeof(ext4_acl_header);
 572         s = sizeof(ext4_acl_header);
 573         for (end = entry + count; entry != end;entry++) {
 574                 ext4_acl_entry *disk_entry = (ext4_acl_entry*) e;
 575                 disk_entry->e_tag = ext2fs_cpu_to_le16(entry->e_tag);
 576                 disk_entry->e_perm = ext2fs_cpu_to_le16(entry->e_perm);
 577
 578                 switch(entry->e_tag) {
 579                         case ACL_USER_OBJ:
 580                         case ACL_GROUP_OBJ:
 581                         case ACL_MASK:
 582                         case ACL_OTHER:
 583                                 e += sizeof(ext4_acl_entry_short);
 584                                 s += sizeof(ext4_acl_entry_short);
 585                                 break;
 586                         case ACL_USER:
 587                         case ACL_GROUP:
 588                                 disk_entry->e_id =  ext2fs_cpu_to_le32(entry->e_id);
 589                                 e += sizeof(ext4_acl_entry);
 590                                 s += sizeof(ext4_acl_entry);
 591                                 break;
 592                 }
 593         }
 594         *size_out = s;
 595         return 0;
 596 }
 597
 598 static errcode_t convert_disk_buffer_to_posix_acl(const void *value, size_t size,
 599                                                   void **out_buf, size_t *size_out)
 600 {
 601         posix_acl_xattr_header *header;
 602         posix_acl_xattr_entry *entry;
 603         ext4_acl_header *ext_acl = (ext4_acl_header *) value;
 604         errcode_t err;
 605         const char *cp;
 606         char *out;
 607
 608         if ((!value) ||
 609             (size < sizeof(ext4_acl_header)) ||
 610             (ext_acl->a_version != ext2fs_cpu_to_le32(EXT4_ACL_VERSION)))
 611                 return EINVAL;
 612
 613         err = ext2fs_get_mem(size * 2, &out);
 614         if (err)
 615                 return err;
 616
 617         header = (posix_acl_xattr_header *) out;
 618         header->a_version = ext2fs_cpu_to_le32(POSIX_ACL_XATTR_VERSION);
 619         entry = (posix_acl_xattr_entry *) (out + sizeof(posix_acl_xattr_header));
 620
 621         cp = value + sizeof(ext4_acl_header);
 622         size -= sizeof(ext4_acl_header);
 623
 624         while (size > 0) {
 625                 const ext4_acl_entry *disk_entry = (const ext4_acl_entry *) cp;
 626
 627                 entry->e_tag = ext2fs_le16_to_cpu(disk_entry->e_tag);
 628                 entry->e_perm = ext2fs_le16_to_cpu(disk_entry->e_perm);
 629
 630                 switch(entry->e_tag) {
 631                         case ACL_USER_OBJ:
 632                         case ACL_GROUP_OBJ:
 633                         case ACL_MASK:
 634                         case ACL_OTHER:
 635                                 entry->e_id = 0;
 636                                 cp += sizeof(ext4_acl_entry_short);
 637                                 size -= sizeof(ext4_acl_entry_short);
 638                                 break;
 639                         case ACL_USER:
 640                         case ACL_GROUP:
 641                                 entry->e_id = ext2fs_le32_to_cpu(disk_entry->e_id);
 642                                 cp += sizeof(ext4_acl_entry);
 643                                 size -= sizeof(ext4_acl_entry);
 644                                 break;
 645                 default:
 646                         ext2fs_free_mem(&out);
 647                         return EINVAL;
 648                         break;
 649                 }
 650                 entry++;
 651         }
 652         *out_buf = out;
 653         *size_out = ((char *) entry - out);
 654         return 0;
 655 }
 656
 657
 658 static errcode_t write_xattrs_to_buffer(struct ext2_xattr_handle *handle,
 659                                         struct ext2_xattr **pos,
 660                                         void *entries_start,
 661                                         unsigned int storage_size,
 662                                         unsigned int value_offset_correction,
 663                                         int write_hash)
 664 {
 665         struct ext2_xattr *x = *pos;
 666         struct ext2_ext_attr_entry *e = entries_start;
 667         char *end = (char *) entries_start + storage_size;
 668         char *shortname;
 669         unsigned int entry_size, value_size;
 670         int idx, ret;
 671
 672         memset(entries_start, 0, storage_size);
 673         /* For all remaining x...  */
 674         for (; x < handle->attrs + handle->count; x++) {
 675                 /* Calculate index and shortname position */
 676                 shortname = x->name;
 677                 ret = find_ea_index(x->name, &shortname, &idx);
 678
 679                 /* Calculate entry and value size */
 680                 entry_size = (sizeof(*e) + strlen(shortname) +
 681                               EXT2_EXT_ATTR_PAD - 1) &
 682                              ~(EXT2_EXT_ATTR_PAD - 1);
 683                 value_size = ((x->value_len + EXT2_EXT_ATTR_PAD - 1) /
 684                               EXT2_EXT_ATTR_PAD) * EXT2_EXT_ATTR_PAD;
 685
 686                 /*
 687                  * Would entry collide with value?
 688                  * Note that we must leave sufficient room for a (u32)0 to
 689                  * mark the end of the entries.
 690                  */
 691                 if ((char *)e + entry_size + sizeof(__u32) > end - value_size)
 692                         break;
 693
 694                 /* Fill out e appropriately */
 695                 e->e_name_len = strlen(shortname);
 696                 e->e_name_index = (ret ? idx : 0);
 697                 e->e_value_offs = end - value_size - (char *)entries_start +
 698                                 value_offset_correction;
 699                 e->e_value_inum = 0;
 700                 e->e_value_size = x->value_len;
 701
 702                 /* Store name and value */
 703                 end -= value_size;
 704                 memcpy((char *)e + sizeof(*e), shortname, e->e_name_len);
 705                 memcpy(end, x->value, e->e_value_size);
 706
 707                 if (write_hash)
 708                         e->e_hash = ext2fs_ext_attr_hash_entry(e, end);
 709                 else
 710                         e->e_hash = 0;
 711
 712                 e = EXT2_EXT_ATTR_NEXT(e);
 713                 *(__u32 *)e = 0;
 714         }
 715         *pos = x;
 716
 717         return 0;
 718 }
 719
 720 errcode_t ext2fs_xattrs_write(struct ext2_xattr_handle *handle)
 721 {
 722         struct ext2_xattr *x;
 723         struct ext2_inode_large *inode;
 724         char *start, *block_buf = NULL;
 725         struct ext2_ext_attr_header *header;
 726         __u32 ea_inode_magic;
 727         blk64_t blk;
 728         unsigned int storage_size;
 729         unsigned int i;
 730         errcode_t err;
 731
 732         EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EA_HANDLE);
 733         i = EXT2_INODE_SIZE(handle->fs->super);
 734         if (i < sizeof(*inode))
 735                 i = sizeof(*inode);
 736         err = ext2fs_get_memzero(i, &inode);
 737         if (err)
 738                 return err;
 739
 740         err = ext2fs_read_inode_full(handle->fs, handle->ino,
 741                                      (struct ext2_inode *)inode,
 742                                      EXT2_INODE_SIZE(handle->fs->super));
 743         if (err)
 744                 goto out;
 745
 746         /* If extra_isize isn't set, we need to set it now */
 747         if (inode->i_extra_isize == 0 &&
 748             EXT2_INODE_SIZE(handle->fs->super) > EXT2_GOOD_OLD_INODE_SIZE) {
 749                 char *p = (char *)inode;
 750                 size_t extra = handle->fs->super->s_want_extra_isize;
 751
 752                 if (extra == 0)
 753                         extra = sizeof(__u32);
 754                 memset(p + EXT2_GOOD_OLD_INODE_SIZE, 0, extra);
 755                 inode->i_extra_isize = extra;
 756         }
 757         if (inode->i_extra_isize & 3) {
 758                 err = EXT2_ET_INODE_CORRUPTED;
 759                 goto out;
 760         }
 761
 762         /* Force the inlinedata attr to the front. */
 763         x = handle->attrs;
 764         qsort(x, handle->count, sizeof(struct ext2_xattr), attr_compare);
 765
 766         /* Does the inode have space for EA? */
 767         if (inode->i_extra_isize < sizeof(inode->i_extra_isize) ||
 768             EXT2_INODE_SIZE(handle->fs->super) <= EXT2_GOOD_OLD_INODE_SIZE +
 769                                                   inode->i_extra_isize +
 770                                                   sizeof(__u32))
 771                 goto write_ea_block;
 772
 773         /* Write the inode EA */
 774         ea_inode_magic = EXT2_EXT_ATTR_MAGIC;
 775         memcpy(((char *) inode) + EXT2_GOOD_OLD_INODE_SIZE +
 776                inode->i_extra_isize, &ea_inode_magic, sizeof(__u32));
 777         storage_size = EXT2_INODE_SIZE(handle->fs->super) -
 778                 EXT2_GOOD_OLD_INODE_SIZE - inode->i_extra_isize -
 779                 sizeof(__u32);
 780         start = ((char *) inode) + EXT2_GOOD_OLD_INODE_SIZE +
 781                 inode->i_extra_isize + sizeof(__u32);
 782
 783         err = write_xattrs_to_buffer(handle, &x, start, storage_size, 0, 0);
 784         if (err)
 785                 goto out;
 786
 787 write_ea_block:
 788         /* Are we done? */
 789         if (x >= handle->attrs + handle->count)
 790                 goto skip_ea_block;
 791
 792         /* Write the EA block */
 793         err = ext2fs_get_memzero(handle->fs->blocksize, &block_buf);
 794         if (err)
 795                 goto out;
 796
 797         storage_size = handle->fs->blocksize -
 798                 sizeof(struct ext2_ext_attr_header);
 799         start = block_buf + sizeof(struct ext2_ext_attr_header);
 800
 801         err = write_xattrs_to_buffer(handle, &x, start, storage_size,
 802                                      start - block_buf, 1);
 803         if (err)
 804                 goto out2;
 805
 806         if (x < handle->attrs + handle->count) {
 807                 err = EXT2_ET_EA_NO_SPACE;
 808                 goto out2;
 809         }
 810
 811         /* Write a header on the EA block */
 812         header = (struct ext2_ext_attr_header *) block_buf;
 813         header->h_magic = EXT2_EXT_ATTR_MAGIC;
 814         header->h_refcount = 1;
 815         header->h_blocks = 1;
 816
 817         /* Get a new block for writing */
 818         err = prep_ea_block_for_write(handle->fs, handle->ino, inode);
 819         if (err)
 820                 goto out2;
 821
 822         /* Finally, write the new EA block */
 823         blk = ext2fs_file_acl_block(handle->fs,
 824                                     (struct ext2_inode *)inode);
 825         err = ext2fs_write_ext_attr3(handle->fs, blk, block_buf,
 826                                      handle->ino);
 827         if (err)
 828                 goto out2;
 829
 830 skip_ea_block:
 831         blk = ext2fs_file_acl_block(handle->fs, (struct ext2_inode *)inode);
 832         if (!block_buf && blk) {
 833                 /* xattrs shrunk, free the block */
 834                 err = ext2fs_free_ext_attr(handle->fs, handle->ino, inode);
 835                 if (err)
 836                         goto out;
 837         }
 838
 839         /* Write the inode */
 840         err = ext2fs_write_inode_full(handle->fs, handle->ino,
 841                                       (struct ext2_inode *)inode,
 842                                       EXT2_INODE_SIZE(handle->fs->super));
 843         if (err)
 844                 goto out2;
 845
 846 out2:
 847         ext2fs_free_mem(&block_buf);
 848 out:
 849         ext2fs_free_mem(&inode);
 850         handle->dirty = 0;
 851         return err;
 852 }
 853
 854 static errcode_t read_xattrs_from_buffer(struct ext2_xattr_handle *handle,
 855                                          struct ext2_inode_large *inode,
 856                                          struct ext2_ext_attr_entry *entries,
 857                                          unsigned int storage_size,
 858                                          char *value_start)
 859 {
 860         struct ext2_xattr *x;
 861         struct ext2_ext_attr_entry *entry, *end;
 862         const char *prefix;
 863         unsigned int remain, prefix_len;
 864         errcode_t err;
 865         unsigned int values_size = storage_size +
 866                         ((char *)entries - value_start);
 867
 868         /* find the end */
 869         end = entries;
 870         remain = storage_size;
 871         while (remain >= sizeof(struct ext2_ext_attr_entry) &&
 872                !EXT2_EXT_IS_LAST_ENTRY(end)) {
 873
 874                 /* header eats this space */
 875                 remain -= sizeof(struct ext2_ext_attr_entry);
 876
 877                 /* is attribute name valid? */
 878                 if (EXT2_EXT_ATTR_SIZE(end->e_name_len) > remain)
 879                         return EXT2_ET_EA_BAD_NAME_LEN;
 880
 881                 /* attribute len eats this space */
 882                 remain -= EXT2_EXT_ATTR_SIZE(end->e_name_len);
 883                 end = EXT2_EXT_ATTR_NEXT(end);
 884         }
 885
 886         entry = entries;
 887         remain = storage_size;
 888         while (remain >= sizeof(struct ext2_ext_attr_entry) &&
 889                !EXT2_EXT_IS_LAST_ENTRY(entry)) {
 890
 891                 /* Allocate space for more attrs? */
 892                 if (handle->count == handle->capacity) {
 893                         err = ext2fs_xattrs_expand(handle, 4);
 894                         if (err)
 895                                 return err;
 896                 }
 897
 898                 x = handle->attrs + handle->count;
 899
 900                 /* header eats this space */
 901                 remain -= sizeof(struct ext2_ext_attr_entry);
 902
 903                 /* attribute len eats this space */
 904                 remain -= EXT2_EXT_ATTR_SIZE(entry->e_name_len);
 905
 906                 /* Extract name */
 907                 prefix = find_ea_prefix(entry->e_name_index);
 908                 prefix_len = (prefix ? strlen(prefix) : 0);
 909                 err = ext2fs_get_memzero(entry->e_name_len + prefix_len + 1,
 910                                          &x->name);
 911                 if (err)
 912                         return err;
 913                 if (prefix)
 914                         memcpy(x->name, prefix, prefix_len);
 915                 if (entry->e_name_len)
 916                         memcpy(x->name + prefix_len,
 917                                (char *)entry + sizeof(*entry),
 918                                entry->e_name_len);
 919
 920                 /* Check & copy value */
 921                 if (!ext2fs_has_feature_ea_inode(handle->fs->super) &&
 922                     entry->e_value_inum != 0)
 923                         return EXT2_ET_BAD_EA_BLOCK_NUM;
 924
 925                 if (entry->e_value_inum == 0) {
 926                         if (entry->e_value_size > remain)
 927                                 return EXT2_ET_EA_BAD_VALUE_SIZE;
 928
 929                         if (entry->e_value_offs + entry->e_value_size > values_size)
 930                                 return EXT2_ET_EA_BAD_VALUE_OFFSET;
 931
 932                         if (entry->e_value_size > 0 &&
 933                             value_start + entry->e_value_offs <
 934                             (char *)end + sizeof(__u32))
 935                                 return EXT2_ET_EA_BAD_VALUE_OFFSET;
 936
 937                         remain -= entry->e_value_size;
 938
 939                         err = ext2fs_get_mem(entry->e_value_size, &x->value);
 940                         if (err)
 941                                 return err;
 942                         memcpy(x->value, value_start + entry->e_value_offs,
 943                                entry->e_value_size);
 944                 } else {
 945                         ext2_file_t ea_file;
 946
 947                         if (entry->e_value_offs != 0)
 948                                 return EXT2_ET_EA_BAD_VALUE_OFFSET;
 949
 950                         if (entry->e_value_size > (64 * 1024))
 951                                 return EXT2_ET_EA_BAD_VALUE_SIZE;
 952
 953                         err = ext2fs_get_mem(entry->e_value_size, &x->value);
 954                         if (err)
 955                                 return err;
 956
 957                         err = ext2fs_file_open(handle->fs, entry->e_value_inum,
 958                                                0, &ea_file);
 959                         if (err)
 960                                 return err;
 961
 962                         if (ext2fs_file_get_size(ea_file) !=
 963                             entry->e_value_size)
 964                                 err = EXT2_ET_EA_BAD_VALUE_SIZE;
 965                         else
 966                                 err = ext2fs_file_read(ea_file, x->value,
 967                                                        entry->e_value_size, 0);
 968                         ext2fs_file_close(ea_file);
 969                         if (err)
 970                                 return err;
 971                 }
 972
 973                 x->value_len = entry->e_value_size;
 974
 975                 /* e_hash may be 0 in older inode's ea */
 976                 if (entry->e_hash != 0) {
 977                         __u32 hash;
 978                         void *data = (entry->e_value_inum != 0) ?
 979                                         0 : value_start + entry->e_value_offs;
 980
 981                         err = ext2fs_ext_attr_hash_entry2(handle->fs, entry,
 982                                                           data, &hash);
 983                         if (err)
 984                                 return err;
 985                         if (entry->e_hash != hash) {
 986                                 struct ext2_inode child;
 987
 988                                 /* Check whether this is an old Lustre-style
 989                                  * ea_inode reference.
 990                                  */
 991                                 err = ext2fs_read_inode(handle->fs,
 992                                                         entry->e_value_inum,
 993                                                         &child);
 994                                 if (err)
 995                                         return err;
 996                                 if (child.i_mtime != handle->ino ||
 997                                     child.i_generation != inode->i_generation)
 998                                         return EXT2_ET_BAD_EA_HASH;
 999                         }
1000                 }
1001
1002                 handle->count++;
1003                 entry = EXT2_EXT_ATTR_NEXT(entry);
1004         }
1005
1006         return 0;
1007 }
1008
1009 static void xattrs_free_keys(struct ext2_xattr_handle *h)
1010 {
1011         struct ext2_xattr *a = h->attrs;
1012         size_t i;
1013
1014         for (i = 0; i < h->capacity; i++) {
1015                 if (a[i].name)
1016                         ext2fs_free_mem(&a[i].name);
1017                 if (a[i].value)
1018                         ext2fs_free_mem(&a[i].value);
1019         }
1020         h->count = 0;
1021 }
1022
1023 errcode_t ext2fs_xattrs_read(struct ext2_xattr_handle *handle)
1024 {
1025         struct ext2_inode_large *inode;
1026         struct ext2_ext_attr_header *header;
1027         __u32 ea_inode_magic;
1028         unsigned int storage_size;
1029         char *start, *block_buf = NULL;
1030         blk64_t blk;
1031         size_t i;
1032         errcode_t err;
1033
1034         EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EA_HANDLE);
1035         i = EXT2_INODE_SIZE(handle->fs->super);
1036         if (i < sizeof(*inode))
1037                 i = sizeof(*inode);
1038         err = ext2fs_get_memzero(i, &inode);
1039         if (err)
1040                 return err;
1041
1042         err = ext2fs_read_inode_full(handle->fs, handle->ino,
1043                                      (struct ext2_inode *)inode,
1044                                      EXT2_INODE_SIZE(handle->fs->super));
1045         if (err)
1046                 goto out;
1047
1048         xattrs_free_keys(handle);
1049
1050         /* Does the inode have space for EA? */
1051         if (inode->i_extra_isize < sizeof(inode->i_extra_isize) ||
1052             EXT2_INODE_SIZE(handle->fs->super) <= EXT2_GOOD_OLD_INODE_SIZE +
1053                                                   inode->i_extra_isize +
1054                                                   sizeof(__u32))
1055                 goto read_ea_block;
1056         if (inode->i_extra_isize & 3) {
1057                 err = EXT2_ET_INODE_CORRUPTED;
1058                 goto out;
1059         }
1060
1061         /* Look for EA in the inode */
1062         memcpy(&ea_inode_magic, ((char *) inode) + EXT2_GOOD_OLD_INODE_SIZE +
1063                inode->i_extra_isize, sizeof(__u32));
1064         if (ea_inode_magic == EXT2_EXT_ATTR_MAGIC) {
1065                 storage_size = EXT2_INODE_SIZE(handle->fs->super) -
1066                         EXT2_GOOD_OLD_INODE_SIZE - inode->i_extra_isize -
1067                         sizeof(__u32);
1068                 start = ((char *) inode) + EXT2_GOOD_OLD_INODE_SIZE +
1069                         inode->i_extra_isize + sizeof(__u32);
1070
1071                 err = read_xattrs_from_buffer(handle, inode,
1072                                         (struct ext2_ext_attr_entry *) start,
1073                                         storage_size, start);
1074                 if (err)
1075                         goto out;
1076         }
1077
1078 read_ea_block:
1079         /* Look for EA in a separate EA block */
1080         blk = ext2fs_file_acl_block(handle->fs, (struct ext2_inode *)inode);
1081         if (blk != 0) {
1082                 if ((blk < handle->fs->super->s_first_data_block) ||
1083                     (blk >= ext2fs_blocks_count(handle->fs->super))) {
1084                         err = EXT2_ET_BAD_EA_BLOCK_NUM;
1085                         goto out;
1086                 }
1087
1088                 err = ext2fs_get_mem(handle->fs->blocksize, &block_buf);
1089                 if (err)
1090                         goto out;
1091
1092                 err = ext2fs_read_ext_attr3(handle->fs, blk, block_buf,
1093                                             handle->ino);
1094                 if (err)
1095                         goto out3;
1096
1097                 /* We only know how to deal with v2 EA blocks */
1098                 header = (struct ext2_ext_attr_header *) block_buf;
1099                 if (header->h_magic != EXT2_EXT_ATTR_MAGIC) {
1100                         err = EXT2_ET_BAD_EA_HEADER;
1101                         goto out3;
1102                 }
1103
1104                 /* Read EAs */
1105                 storage_size = handle->fs->blocksize -
1106                         sizeof(struct ext2_ext_attr_header);
1107                 start = block_buf + sizeof(struct ext2_ext_attr_header);
1108                 err = read_xattrs_from_buffer(handle, inode,
1109                                         (struct ext2_ext_attr_entry *) start,
1110                                         storage_size, block_buf);
1111                 if (err)
1112                         goto out3;
1113
1114                 ext2fs_free_mem(&block_buf);
1115         }
1116
1117         ext2fs_free_mem(&block_buf);
1118         ext2fs_free_mem(&inode);
1119         return 0;
1120
1121 out3:
1122         ext2fs_free_mem(&block_buf);
1123 out:
1124         ext2fs_free_mem(&inode);
1125         return err;
1126 }
1127
1128 errcode_t ext2fs_xattrs_iterate(struct ext2_xattr_handle *h,
1129                                 int (*func)(char *name, char *value,
1130                                             size_t value_len, void *data),
1131                                 void *data)
1132 {
1133         struct ext2_xattr *x;
1134         int ret;
1135
1136         EXT2_CHECK_MAGIC(h, EXT2_ET_MAGIC_EA_HANDLE);
1137         for (x = h->attrs; x < h->attrs + h->count; x++) {
1138                 ret = func(x->name, x->value, x->value_len, data);
1139                 if (ret & XATTR_CHANGED)
1140                         h->dirty = 1;
1141                 if (ret & XATTR_ABORT)
1142                         return 0;
1143         }
1144
1145         return 0;
1146 }
1147
1148 errcode_t ext2fs_xattr_get(struct ext2_xattr_handle *h, const char *key,
1149                            void **value, size_t *value_len)
1150 {
1151         struct ext2_xattr *x;
1152         char *val;
1153         errcode_t err;
1154
1155         EXT2_CHECK_MAGIC(h, EXT2_ET_MAGIC_EA_HANDLE);
1156         for (x = h->attrs; x < h->attrs + h->count; x++) {
1157                 if (strcmp(x->name, key))
1158                         continue;
1159
1160                 if (!(h->flags & XATTR_HANDLE_FLAG_RAW) &&
1161                     ((strcmp(key, "system.posix_acl_default") == 0) ||
1162                      (strcmp(key, "system.posix_acl_access") == 0))) {
1163                         err = convert_disk_buffer_to_posix_acl(x->value, x->value_len,
1164                                                                value, value_len);
1165                         return err;
1166                 } else {
1167                         err = ext2fs_get_mem(x->value_len, &val);
1168                         if (err)
1169                                 return err;
1170                         memcpy(val, x->value, x->value_len);
1171                         *value = val;
1172                         *value_len = x->value_len;
1173                         return 0;
1174                 }
1175         }
1176
1177         return EXT2_ET_EA_KEY_NOT_FOUND;
1178 }
1179
1180 errcode_t ext2fs_xattr_inode_max_size(ext2_filsys fs, ext2_ino_t ino,
1181                                       size_t *size)
1182 {
1183         struct ext2_ext_attr_entry *entry;
1184         struct ext2_inode_large *inode;
1185         __u32 ea_inode_magic;
1186         unsigned int minoff;
1187         char *start;
1188         size_t i;
1189         errcode_t err;
1190
1191         i = EXT2_INODE_SIZE(fs->super);
1192         if (i < sizeof(*inode))
1193                 i = sizeof(*inode);
1194         err = ext2fs_get_memzero(i, &inode);
1195         if (err)
1196                 return err;
1197
1198         err = ext2fs_read_inode_full(fs, ino, (struct ext2_inode *)inode,
1199                                      EXT2_INODE_SIZE(fs->super));
1200         if (err)
1201                 goto out;
1202
1203         /* Does the inode have size for EA? */
1204         if (EXT2_INODE_SIZE(fs->super) <= EXT2_GOOD_OLD_INODE_SIZE +
1205                                                   inode->i_extra_isize +
1206                                                   sizeof(__u32)) {
1207                 err = EXT2_ET_INLINE_DATA_NO_SPACE;
1208                 goto out;
1209         }
1210
1211         minoff = EXT2_INODE_SIZE(fs->super) - sizeof(*inode) - sizeof(__u32);
1212         memcpy(&ea_inode_magic, ((char *) inode) + EXT2_GOOD_OLD_INODE_SIZE +
1213                inode->i_extra_isize, sizeof(__u32));
1214         if (ea_inode_magic == EXT2_EXT_ATTR_MAGIC) {
1215                 /* has xattrs.  calculate the size */
1216                 start= ((char *) inode) + EXT2_GOOD_OLD_INODE_SIZE +
1217                         inode->i_extra_isize + sizeof(__u32);
1218                 entry = (struct ext2_ext_attr_entry *) start;
1219                 while (!EXT2_EXT_IS_LAST_ENTRY(entry)) {
1220                         if (!entry->e_value_inum && entry->e_value_size) {
1221                                 unsigned int offs = entry->e_value_offs;
1222                                 if (offs < minoff)
1223                                         minoff = offs;
1224                         }
1225                         entry = EXT2_EXT_ATTR_NEXT(entry);
1226                 }
1227                 *size = minoff - ((char *)entry - (char *)start) - sizeof(__u32);
1228         } else {
1229                 /* no xattr.  return a maximum size */
1230                 *size = EXT2_EXT_ATTR_SIZE(minoff -
1231                                            EXT2_EXT_ATTR_LEN(strlen("data")) -
1232                                            EXT2_EXT_ATTR_ROUND - sizeof(__u32));
1233         }
1234
1235 out:
1236         ext2fs_free_mem(&inode);
1237         return err;
1238 }
1239
1240 errcode_t ext2fs_xattr_set(struct ext2_xattr_handle *handle,
1241                            const char *key,
1242                            const void *value,
1243                            size_t value_len)
1244 {
1245         struct ext2_xattr *x;
1246         char *new_value;
1247         errcode_t err;
1248
1249         EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EA_HANDLE);
1250
1251         err = ext2fs_get_mem(value_len, &new_value);
1252         if (err)
1253                 return err;
1254         if (!(handle->flags & XATTR_HANDLE_FLAG_RAW) &&
1255             ((strcmp(key, "system.posix_acl_default") == 0) ||
1256              (strcmp(key, "system.posix_acl_access") == 0))) {
1257                 err = convert_posix_acl_to_disk_buffer(value, value_len,
1258                                                        new_value, &value_len);
1259                 if (err)
1260                         goto errout;
1261         } else
1262                 memcpy(new_value, value, value_len);
1263
1264         for (x = handle->attrs; x < handle->attrs + handle->count; x++) {
1265                 /* Replace xattr */
1266                 if (strcmp(x->name, key) == 0) {
1267                         ext2fs_free_mem(&x->value);
1268                         x->value = new_value;
1269                         x->value_len = value_len;
1270                         handle->dirty = 1;
1271                         return 0;
1272                 }
1273         }
1274
1275         if (handle->count == handle->capacity) {
1276                 /* Expand array, append slot */
1277                 err = ext2fs_xattrs_expand(handle, 4);
1278                 if (err)
1279                         goto errout;
1280
1281                 x = handle->attrs + handle->capacity - 4;
1282         }
1283
1284         err = ext2fs_get_mem(strlen(key) + 1, &x->name);
1285         if (err)
1286                 goto errout;
1287         strcpy(x->name, key);
1288
1289         err = ext2fs_get_mem(value_len, &x->value);
1290         if (err)
1291                 goto errout;
1292         memcpy(x->value, value, value_len);
1293         x->value_len = value_len;
1294         handle->dirty = 1;
1295         handle->count++;
1296         return 0;
1297 errout:
1298         ext2fs_free_mem(&new_value);
1299         return err;
1300 }
1301
1302 errcode_t ext2fs_xattr_remove(struct ext2_xattr_handle *handle,
1303                               const char *key)
1304 {
1305         struct ext2_xattr *x;
1306         struct ext2_xattr *end = handle->attrs + handle->count;
1307
1308         EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EA_HANDLE);
1309         for (x = handle->attrs; x < end; x++) {
1310                 if (strcmp(x->name, key) == 0) {
1311                         ext2fs_free_mem(&x->name);
1312                         ext2fs_free_mem(&x->value);
1313                         memmove(x, x + 1, (char *)end - (char *)(x + 1));
1314                         memset(end, 0, sizeof(*end));
1315                         handle->dirty = 1;
1316                         handle->count--;
1317                         return 0;
1318                 }
1319         }
1320
1321         /* no key found, success! */
1322         return 0;
1323 }
1324
1325 errcode_t ext2fs_xattrs_open(ext2_filsys fs, ext2_ino_t ino,
1326                              struct ext2_xattr_handle **handle)
1327 {
1328         struct ext2_xattr_handle *h;
1329         errcode_t err;
1330
1331         if (!ext2fs_has_feature_xattr(fs->super) &&
1332             !ext2fs_has_feature_inline_data(fs->super))
1333                 return EXT2_ET_MISSING_EA_FEATURE;
1334
1335         err = ext2fs_get_memzero(sizeof(*h), &h);
1336         if (err)
1337                 return err;
1338
1339         h->magic = EXT2_ET_MAGIC_EA_HANDLE;
1340         h->capacity = 4;
1341         err = ext2fs_get_arrayzero(h->capacity, sizeof(struct ext2_xattr),
1342                                    &h->attrs);
1343         if (err) {
1344                 ext2fs_free_mem(&h);
1345                 return err;
1346         }
1347         h->count = 0;
1348         h->ino = ino;
1349         h->fs = fs;
1350         *handle = h;
1351         return 0;
1352 }
1353
1354 errcode_t ext2fs_xattrs_close(struct ext2_xattr_handle **handle)
1355 {
1356         struct ext2_xattr_handle *h = *handle;
1357         errcode_t err;
1358
1359         EXT2_CHECK_MAGIC(h, EXT2_ET_MAGIC_EA_HANDLE);
1360         if (h->dirty) {
1361                 err = ext2fs_xattrs_write(h);
1362                 if (err)
1363                         return err;
1364         }
1365
1366         xattrs_free_keys(h);
1367         ext2fs_free_mem(&h->attrs);
1368         ext2fs_free_mem(handle);
1369         return 0;
1370 }
1371
1372 errcode_t ext2fs_xattrs_count(struct ext2_xattr_handle *handle, size_t *count)
1373 {
1374         EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EA_HANDLE);
1375         *count = handle->count;
1376         return 0;
1377 }
1378
1379 errcode_t ext2fs_xattrs_flags(struct ext2_xattr_handle *handle,
1380                               unsigned int *new_flags, unsigned int *old_flags)
1381 {
1382         EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EA_HANDLE);
1383         if (old_flags)
1384                 *old_flags = handle->flags;
1385         if (new_flags)
1386                 handle->flags = *new_flags;
1387         return 0;
1388 }