wimlib.net Git - wimlib/blob - src/ntfs-capture.c

   1 /*
   2  * ntfs-capture.c
   3  *
   4  * Capture a WIM image from a NTFS volume.  We capture everything we can,
   5  * including security data and alternate data streams.
   6  */
   7
   8 /*
   9  * Copyright (C) 2012 Eric Biggers
  10  *
  11  * This file is part of wimlib, a library for working with WIM files.
  12  *
  13  * wimlib is free software; you can redistribute it and/or modify it under the
  14  * terms of the GNU General Public License as published by the Free
  15  * Software Foundation; either version 3 of the License, or (at your option)
  16  * any later version.
  17  *
  18  * wimlib is distributed in the hope that it will be useful, but WITHOUT ANY
  19  * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
  20  * A PARTICULAR PURPOSE. See the GNU General Public License for more
  21  * details.
  22  *
  23  * You should have received a copy of the GNU General Public License
  24  * along with wimlib; if not, see http://www.gnu.org/licenses/.
  25  */
  26
  27
  28 #include "config.h"
  29
  30 #include <ntfs-3g/endians.h>
  31 #include <ntfs-3g/types.h>
  32
  33 #include "wimlib_internal.h"
  34
  35
  36 #include "dentry.h"
  37 #include "lookup_table.h"
  38 #include "buffer_io.h"
  39 #include <ntfs-3g/layout.h>
  40 #include <ntfs-3g/acls.h>
  41 #include <ntfs-3g/attrib.h>
  42 #include <ntfs-3g/misc.h>
  43 #include <ntfs-3g/reparse.h>
  44 #include <ntfs-3g/security.h> /* security.h before xattrs.h */
  45 #include <ntfs-3g/xattrs.h>
  46 #include <ntfs-3g/volume.h>
  47 #include <stdlib.h>
  48 #include <unistd.h>
  49 #include <errno.h>
  50 #include "rbtree.h"
  51
  52 /* Structure that allows searching the security descriptors by SHA1 message
  53  * digest. */
  54 struct sd_set {
  55         struct wim_security_data *sd;
  56         struct rb_root rb_root;
  57 };
  58
  59 /* Binary tree node of security descriptors, indexed by the @hash field. */
  60 struct sd_node {
  61         int security_id;
  62         u8 hash[SHA1_HASH_SIZE];
  63         struct rb_node rb_node;
  64 };
  65
  66 static void free_sd_tree(struct rb_node *node)
  67 {
  68         if (node) {
  69                 free_sd_tree(node->rb_left);
  70                 free_sd_tree(node->rb_right);
  71                 FREE(container_of(node, struct sd_node, rb_node));
  72         }
  73 }
  74 /* Frees a security descriptor index set. */
  75 static void destroy_sd_set(struct sd_set *sd_set)
  76 {
  77         free_sd_tree(sd_set->rb_root.rb_node);
  78 }
  79
  80 /* Inserts a a new node into the security descriptor index tree. */
  81 static void insert_sd_node(struct sd_set *set, struct sd_node *new)
  82 {
  83         struct rb_root *root = &set->rb_root;
  84         struct rb_node **p = &(root->rb_node);
  85         struct rb_node *rb_parent = NULL;
  86
  87         while (*p) {
  88                 struct sd_node *this = container_of(*p, struct sd_node, rb_node);
  89                 int cmp = hashes_cmp(new->hash, this->hash);
  90
  91                 rb_parent = *p;
  92                 if (cmp < 0)
  93                         p = &((*p)->rb_left);
  94                 else if (cmp > 0)
  95                         p = &((*p)->rb_right);
  96                 else
  97                         wimlib_assert(0); /* Duplicate SHA1 message digest */
  98         }
  99         rb_link_node(&new->rb_node, rb_parent, p);
 100         rb_insert_color(&new->rb_node, root);
 101 }
 102
 103 /* Returns the index of the security descriptor having a SHA1 message digest of
 104  * @hash.  If not found, return -1. */
 105 static int lookup_sd(struct sd_set *set, const u8 hash[SHA1_HASH_SIZE])
 106 {
 107         struct rb_node *node = set->rb_root.rb_node;
 108
 109         while (node) {
 110                 struct sd_node *sd_node = container_of(node, struct sd_node, rb_node);
 111                 int cmp = hashes_cmp(hash, sd_node->hash);
 112                 if (cmp < 0)
 113                         node = node->rb_left;
 114                 else if (cmp > 0)
 115                         node = node->rb_right;
 116                 else
 117                         return sd_node->security_id;
 118         }
 119         return -1;
 120 }
 121
 122 /*
 123  * Adds a security descriptor to the indexed security descriptor set as well as
 124  * the corresponding `struct wim_security_data', and returns the new security
 125  * ID; or, if there is an existing security descriptor that is the same, return
 126  * the security ID for it.  If a new security descriptor cannot be allocated,
 127  * return -1.
 128  */
 129 static int sd_set_add_sd(struct sd_set *sd_set, const char descriptor[],
 130                          size_t size)
 131 {
 132         u8 hash[SHA1_HASH_SIZE];
 133         int security_id;
 134         struct sd_node *new;
 135         u8 **descriptors;
 136         u64 *sizes;
 137         u8 *descr_copy;
 138         struct wim_security_data *sd;
 139
 140         sha1_buffer((const u8*)descriptor, size, hash);
 141
 142         security_id = lookup_sd(sd_set, hash);
 143         if (security_id >= 0) /* Identical descriptor already exists */
 144                 return security_id;
 145
 146         /* Need to add a new security descriptor */
 147         new = MALLOC(sizeof(*new));
 148         if (!new)
 149                 goto out;
 150         descr_copy = MALLOC(size);
 151         if (!descr_copy)
 152                 goto out_free_node;
 153
 154         sd = sd_set->sd;
 155
 156         memcpy(descr_copy, descriptor, size);
 157         new->security_id = sd->num_entries;
 158         copy_hash(new->hash, hash);
 159
 160         descriptors = REALLOC(sd->descriptors,
 161                               (sd->num_entries + 1) * sizeof(sd->descriptors[0]));
 162         if (!descriptors)
 163                 goto out_free_descr;
 164         sd->descriptors = descriptors;
 165         sizes = REALLOC(sd->sizes,
 166                         (sd->num_entries + 1) * sizeof(sd->sizes[0]));
 167         if (!sizes)
 168                 goto out_free_descr;
 169         sd->sizes = sizes;
 170         sd->descriptors[sd->num_entries] = descr_copy;
 171         sd->sizes[sd->num_entries] = size;
 172         sd->num_entries++;
 173         DEBUG("There are now %d security descriptors", sd->num_entries);
 174         sd->total_length += size + sizeof(sd->sizes[0]);
 175         insert_sd_node(sd_set, new);
 176         return new->security_id;
 177 out_free_descr:
 178         FREE(descr_copy);
 179 out_free_node:
 180         FREE(new);
 181 out:
 182         return -1;
 183 }
 184
 185 static inline ntfschar *attr_record_name(ATTR_RECORD *ar)
 186 {
 187         return (ntfschar*)((u8*)ar + le16_to_cpu(ar->name_offset));
 188 }
 189
 190 /* Calculates the SHA1 message digest of a NTFS attribute.
 191  *
 192  * @ni:  The NTFS inode containing the attribute.
 193  * @ar:  The ATTR_RECORD describing the attribute.
 194  * @md:  If successful, the returned SHA1 message digest.
 195  * @reparse_tag_ret:    Optional pointer into which the first 4 bytes of the
 196  *                              attribute will be written (to get the reparse
 197  *                              point ID)
 198  *
 199  * Return 0 on success or nonzero on error.
 200  */
 201 static int ntfs_attr_sha1sum(ntfs_inode *ni, ATTR_RECORD *ar,
 202                              u8 md[SHA1_HASH_SIZE],
 203                              bool is_reparse_point,
 204                              u32 *reparse_tag_ret)
 205 {
 206         s64 pos = 0;
 207         s64 bytes_remaining;
 208         char buf[BUFFER_SIZE];
 209         ntfs_attr *na;
 210         SHA_CTX ctx;
 211
 212         na = ntfs_attr_open(ni, ar->type, attr_record_name(ar),
 213                             ar->name_length);
 214         if (!na) {
 215                 ERROR_WITH_ERRNO("Failed to open NTFS attribute");
 216                 return WIMLIB_ERR_NTFS_3G;
 217         }
 218
 219         bytes_remaining = na->data_size;
 220
 221         if (is_reparse_point) {
 222                 if (ntfs_attr_pread(na, 0, 8, buf) != 8)
 223                         goto out_error;
 224                 *reparse_tag_ret = le32_to_cpu(*(u32*)buf);
 225                 pos = 8;
 226                 bytes_remaining -= 8;
 227         }
 228
 229         sha1_init(&ctx);
 230         while (bytes_remaining) {
 231                 s64 to_read = min(bytes_remaining, sizeof(buf));
 232                 if (ntfs_attr_pread(na, pos, to_read, buf) != to_read)
 233                         goto out_error;
 234                 sha1_update(&ctx, buf, to_read);
 235                 pos += to_read;
 236                 bytes_remaining -= to_read;
 237         }
 238         sha1_final(md, &ctx);
 239         ntfs_attr_close(na);
 240         return 0;
 241 out_error:
 242         ERROR_WITH_ERRNO("Error reading NTFS attribute");
 243         return WIMLIB_ERR_NTFS_3G;
 244 }
 245
 246 /* Load the streams from a file or reparse point in the NTFS volume into the WIM
 247  * lookup table */
 248 static int capture_ntfs_streams(struct wim_dentry *dentry, ntfs_inode *ni,
 249                                 char path[], size_t path_len,
 250                                 struct wim_lookup_table *lookup_table,
 251                                 ntfs_volume **ntfs_vol_p,
 252                                 ATTR_TYPES type)
 253 {
 254         ntfs_attr_search_ctx *actx;
 255         u8 attr_hash[SHA1_HASH_SIZE];
 256         struct ntfs_location *ntfs_loc = NULL;
 257         int ret = 0;
 258         struct wim_lookup_table_entry *lte;
 259
 260         DEBUG2("Capturing NTFS data streams from `%s'", path);
 261
 262         /* Get context to search the streams of the NTFS file. */
 263         actx = ntfs_attr_get_search_ctx(ni, NULL);
 264         if (!actx) {
 265                 ERROR_WITH_ERRNO("Cannot get NTFS attribute search "
 266                                  "context");
 267                 return WIMLIB_ERR_NTFS_3G;
 268         }
 269
 270         /* Capture each data stream or reparse data stream. */
 271         while (!ntfs_attr_lookup(type, NULL, 0,
 272                                  CASE_SENSITIVE, 0, NULL, 0, actx))
 273         {
 274                 char *stream_name_utf8;
 275                 u32 reparse_tag;
 276                 u64 data_size = ntfs_get_attribute_value_length(actx->attr);
 277                 u64 name_length = actx->attr->name_length;
 278
 279                 if (data_size == 0) {
 280                         if (errno != 0) {
 281                                 ERROR_WITH_ERRNO("Failed to get size of attribute of "
 282                                                  "`%s'", path);
 283                                 ret = WIMLIB_ERR_NTFS_3G;
 284                                 goto out_put_actx;
 285                         }
 286                         /* Empty stream.  No lookup table entry is needed. */
 287                         lte = NULL;
 288                 } else {
 289                         if (type == AT_REPARSE_POINT && data_size < 8) {
 290                                 ERROR("`%s': reparse point buffer too small",
 291                                       path);
 292                                 ret = WIMLIB_ERR_NTFS_3G;
 293                                 goto out_put_actx;
 294                         }
 295                         /* Checksum the stream. */
 296                         ret = ntfs_attr_sha1sum(ni, actx->attr, attr_hash,
 297                                                 type == AT_REPARSE_POINT, &reparse_tag);
 298                         if (ret != 0)
 299                                 goto out_put_actx;
 300
 301                         /* Make a lookup table entry for the stream, or use an existing
 302                          * one if there's already an identical stream. */
 303                         lte = __lookup_resource(lookup_table, attr_hash);
 304                         ret = WIMLIB_ERR_NOMEM;
 305                         if (lte) {
 306                                 lte->refcnt++;
 307                         } else {
 308                                 ntfs_loc = CALLOC(1, sizeof(*ntfs_loc));
 309                                 if (!ntfs_loc)
 310                                         goto out_put_actx;
 311                                 ntfs_loc->ntfs_vol_p = ntfs_vol_p;
 312                                 ntfs_loc->path_utf8 = MALLOC(path_len + 1);
 313                                 if (!ntfs_loc->path_utf8)
 314                                         goto out_free_ntfs_loc;
 315                                 memcpy(ntfs_loc->path_utf8, path, path_len + 1);
 316                                 if (name_length) {
 317                                         ntfs_loc->stream_name_utf16 = MALLOC(name_length * 2);
 318                                         if (!ntfs_loc->stream_name_utf16)
 319                                                 goto out_free_ntfs_loc;
 320                                         memcpy(ntfs_loc->stream_name_utf16,
 321                                                attr_record_name(actx->attr),
 322                                                actx->attr->name_length * 2);
 323                                         ntfs_loc->stream_name_utf16_num_chars = name_length;
 324                                 }
 325
 326                                 lte = new_lookup_table_entry();
 327                                 if (!lte)
 328                                         goto out_free_ntfs_loc;
 329                                 lte->ntfs_loc = ntfs_loc;
 330                                 lte->resource_location = RESOURCE_IN_NTFS_VOLUME;
 331                                 if (type == AT_REPARSE_POINT) {
 332                                         dentry->d_inode->i_reparse_tag = reparse_tag;
 333                                         ntfs_loc->is_reparse_point = true;
 334                                         lte->resource_entry.original_size = data_size - 8;
 335                                         lte->resource_entry.size = data_size - 8;
 336                                 } else {
 337                                         ntfs_loc->is_reparse_point = false;
 338                                         lte->resource_entry.original_size = data_size;
 339                                         lte->resource_entry.size = data_size;
 340                                 }
 341                                 ntfs_loc = NULL;
 342                                 DEBUG("Add resource for `%s' (size = %"PRIu64")",
 343                                       dentry->file_name_utf8,
 344                                       lte->resource_entry.original_size);
 345                                 copy_hash(lte->hash, attr_hash);
 346                                 lookup_table_insert(lookup_table, lte);
 347                         }
 348                 }
 349                 if (name_length == 0) {
 350                         /* Unnamed data stream.  Put the reference to it in the
 351                          * dentry's inode. */
 352                         if (dentry->d_inode->i_lte) {
 353                                 ERROR("Found two un-named data streams for "
 354                                       "`%s'", path);
 355                                 ret = WIMLIB_ERR_NTFS_3G;
 356                                 goto out_free_lte;
 357                         }
 358                         dentry->d_inode->i_lte = lte;
 359                 } else {
 360                         /* Named data stream.  Put the reference to it in the
 361                          * alternate data stream entries */
 362                         struct wim_ads_entry *new_ads_entry;
 363                         size_t stream_name_utf8_len;
 364
 365                         ret = utf16_to_utf8((const char*)attr_record_name(actx->attr),
 366                                             name_length * 2,
 367                                             &stream_name_utf8,
 368                                             &stream_name_utf8_len);
 369                         if (ret != 0)
 370                                 goto out_free_lte;
 371                         new_ads_entry = inode_add_ads(dentry->d_inode, stream_name_utf8);
 372                         FREE(stream_name_utf8);
 373                         if (!new_ads_entry)
 374                                 goto out_free_lte;
 375
 376                         wimlib_assert(new_ads_entry->stream_name_len == name_length * 2);
 377
 378                         new_ads_entry->lte = lte;
 379                 }
 380         }
 381         ret = 0;
 382         goto out_put_actx;
 383 out_free_lte:
 384         free_lookup_table_entry(lte);
 385 out_free_ntfs_loc:
 386         if (ntfs_loc) {
 387                 FREE(ntfs_loc->path_utf8);
 388                 FREE(ntfs_loc->stream_name_utf16);
 389                 FREE(ntfs_loc);
 390         }
 391 out_put_actx:
 392         ntfs_attr_put_search_ctx(actx);
 393         if (ret == 0)
 394                 DEBUG2("Successfully captured NTFS streams from `%s'", path);
 395         else
 396                 ERROR("Failed to capture NTFS streams from `%s", path);
 397         return ret;
 398 }
 399
 400 struct readdir_ctx {
 401         struct wim_dentry           *parent;
 402         ntfs_inode          *dir_ni;
 403         char                *path;
 404         size_t               path_len;
 405         struct wim_lookup_table *lookup_table;
 406         struct sd_set       *sd_set;
 407         const struct capture_config *config;
 408         ntfs_volume        **ntfs_vol_p;
 409         int                  add_image_flags;
 410         wimlib_progress_func_t progress_func;
 411 };
 412
 413 static int
 414 build_dentry_tree_ntfs_recursive(struct wim_dentry **root_p, ntfs_inode *dir_ni,
 415                                  ntfs_inode *ni, char path[], size_t path_len,
 416                                  int name_type,
 417                                  struct wim_lookup_table *lookup_table,
 418                                  struct sd_set *sd_set,
 419                                  const struct capture_config *config,
 420                                  ntfs_volume **ntfs_vol_p,
 421                                  int add_image_flags,
 422                                  wimlib_progress_func_t progress_func);
 423
 424 static int wim_ntfs_capture_filldir(void *dirent, const ntfschar *name,
 425                                     const int name_len, const int name_type,
 426                                     const s64 pos, const MFT_REF mref,
 427                                     const unsigned dt_type)
 428 {
 429         struct readdir_ctx *ctx;
 430         size_t utf8_name_len;
 431         char *utf8_name;
 432         struct wim_dentry *child = NULL;
 433         int ret;
 434         size_t path_len;
 435
 436         if (name_type == FILE_NAME_DOS)
 437                 return 0;
 438
 439         ret = utf16_to_utf8((const char*)name, name_len * 2,
 440                             &utf8_name, &utf8_name_len);
 441         if (ret != 0)
 442                 return -1;
 443
 444         if (utf8_name[0] == '.' &&
 445              (utf8_name[1] == '\0' ||
 446               (utf8_name[1] == '.' && utf8_name[2] == '\0'))) {
 447                 ret = 0;
 448                 goto out_free_utf8_name;
 449         }
 450
 451         ctx = dirent;
 452
 453         ntfs_inode *ni = ntfs_inode_open(ctx->dir_ni->vol, mref);
 454         if (!ni) {
 455                 ERROR_WITH_ERRNO("Failed to open NTFS inode");
 456                 goto out_free_utf8_name;
 457         }
 458         path_len = ctx->path_len;
 459         if (path_len != 1)
 460                 ctx->path[path_len++] = '/';
 461         memcpy(ctx->path + path_len, utf8_name, utf8_name_len + 1);
 462         path_len += utf8_name_len;
 463         ret = build_dentry_tree_ntfs_recursive(&child, ctx->dir_ni,
 464                                                ni, ctx->path, path_len, name_type,
 465                                                ctx->lookup_table, ctx->sd_set,
 466                                                ctx->config, ctx->ntfs_vol_p,
 467                                                ctx->add_image_flags,
 468                                                ctx->progress_func);
 469
 470         if (child)
 471                 dentry_add_child(ctx->parent, child);
 472
 473         ntfs_inode_close(ni);
 474 out_free_utf8_name:
 475         FREE(utf8_name);
 476         return ret;
 477 }
 478
 479 static int change_dentry_short_name(struct wim_dentry *dentry,
 480                                     const char short_name_utf8[],
 481                                     int short_name_utf8_len)
 482 {
 483         size_t short_name_utf16_len;
 484         char *short_name_utf16;
 485         int ret;
 486
 487         ret = utf8_to_utf16(short_name_utf8, short_name_utf8_len,
 488                             &short_name_utf16, &short_name_utf16_len);
 489         if (ret == 0) {
 490                 dentry->short_name = short_name_utf16;
 491                 dentry->short_name_len = short_name_utf16_len;
 492         }
 493         return ret;
 494 }
 495
 496 /* Recursively build a WIM dentry tree corresponding to a NTFS volume.
 497  * At the same time, update the WIM lookup table with lookup table entries for
 498  * the NTFS streams, and build an array of security descriptors.
 499  */
 500 static int build_dentry_tree_ntfs_recursive(struct wim_dentry **root_p,
 501                                             ntfs_inode *dir_ni,
 502                                             ntfs_inode *ni,
 503                                             char path[],
 504                                             size_t path_len,
 505                                             int name_type,
 506                                             struct wim_lookup_table *lookup_table,
 507                                             struct sd_set *sd_set,
 508                                             const struct capture_config *config,
 509                                             ntfs_volume **ntfs_vol_p,
 510                                             int add_image_flags,
 511                                             wimlib_progress_func_t progress_func)
 512 {
 513         u32 attributes;
 514         int mrec_flags;
 515         int ret;
 516         struct wim_dentry *root;
 517
 518         if (exclude_path(path, config, false)) {
 519                 if ((add_image_flags & WIMLIB_ADD_IMAGE_FLAG_VERBOSE)
 520                     && progress_func)
 521                 {
 522                         union wimlib_progress_info info;
 523                         info.scan.cur_path = path;
 524                         info.scan.excluded = true;
 525                         progress_func(WIMLIB_PROGRESS_MSG_SCAN_DENTRY, &info);
 526                 }
 527                 *root_p = NULL;
 528                 return 0;
 529         }
 530
 531         mrec_flags = ni->mrec->flags;
 532         struct SECURITY_CONTEXT ctx;
 533         memset(&ctx, 0, sizeof(ctx));
 534         ctx.vol = ni->vol;
 535         ret = ntfs_xattr_system_getxattr(&ctx, XATTR_NTFS_ATTRIB,
 536                                          ni, dir_ni, (char *)&attributes,
 537                                          sizeof(u32));
 538         if (ret != 4) {
 539                 ERROR_WITH_ERRNO("Failed to get NTFS attributes from `%s'",
 540                                  path);
 541                 return WIMLIB_ERR_NTFS_3G;
 542         }
 543
 544         if ((add_image_flags & WIMLIB_ADD_IMAGE_FLAG_VERBOSE)
 545             && progress_func)
 546         {
 547                 union wimlib_progress_info info;
 548                 info.scan.cur_path = path;
 549                 info.scan.excluded = false;
 550                 progress_func(WIMLIB_PROGRESS_MSG_SCAN_DENTRY, &info);
 551         }
 552
 553         root = new_dentry_with_timeless_inode(path_basename(path));
 554         if (!root) {
 555                 if (errno == EILSEQ)
 556                         return WIMLIB_ERR_INVALID_UTF8_STRING;
 557                 else if (errno == ENOMEM)
 558                         return WIMLIB_ERR_NOMEM;
 559                 else
 560                         return WIMLIB_ERR_ICONV_NOT_AVAILABLE;
 561         }
 562         *root_p = root;
 563
 564         if (dir_ni && (name_type == FILE_NAME_WIN32_AND_DOS
 565                        || name_type == FILE_NAME_WIN32))
 566         {
 567                 char dos_name_utf8[12 * 4 + 1] = {0};
 568                 ret = ntfs_get_ntfs_dos_name(ni, dir_ni, dos_name_utf8,
 569                                              sizeof(dos_name_utf8) - 1);
 570                 if (ret > 0) {
 571                         DEBUG("Changing short name of `%s'", path);
 572                         ret = change_dentry_short_name(root, dos_name_utf8,
 573                                                        ret);
 574                         if (ret != 0)
 575                                 return ret;
 576                 } else {
 577                         if (
 578                 #ifdef ENODATA
 579                             errno != ENODATA &&
 580                 #endif
 581                             errno != EMLINK
 582                             ) {
 583                                 ERROR_WITH_ERRNO("Error getting DOS name "
 584                                                  "of `%s'", path);
 585                                 return WIMLIB_ERR_NTFS_3G;
 586                         }
 587                 }
 588         }
 589
 590         root->d_inode->i_creation_time    = le64_to_cpu(ni->creation_time);
 591         root->d_inode->i_last_write_time  = le64_to_cpu(ni->last_data_change_time);
 592         root->d_inode->i_last_access_time = le64_to_cpu(ni->last_access_time);
 593         root->d_inode->i_attributes       = le32_to_cpu(attributes);
 594         root->d_inode->i_ino              = ni->mft_no;
 595         root->d_inode->i_resolved         = 1;
 596
 597         if (attributes & FILE_ATTR_REPARSE_POINT) {
 598                 /* Junction point, symbolic link, or other reparse point */
 599                 ret = capture_ntfs_streams(root, ni, path, path_len,
 600                                            lookup_table, ntfs_vol_p,
 601                                            AT_REPARSE_POINT);
 602         } else if (mrec_flags & MFT_RECORD_IS_DIRECTORY) {
 603
 604                 /* Normal directory */
 605                 s64 pos = 0;
 606                 struct readdir_ctx ctx = {
 607                         .parent       = root,
 608                         .dir_ni       = ni,
 609                         .path         = path,
 610                         .path_len     = path_len,
 611                         .lookup_table = lookup_table,
 612                         .sd_set       = sd_set,
 613                         .config       = config,
 614                         .ntfs_vol_p   = ntfs_vol_p,
 615                         .add_image_flags = add_image_flags,
 616                         .progress_func = progress_func,
 617                 };
 618                 ret = ntfs_readdir(ni, &pos, &ctx, wim_ntfs_capture_filldir);
 619                 if (ret != 0) {
 620                         ERROR_WITH_ERRNO("ntfs_readdir()");
 621                         ret = WIMLIB_ERR_NTFS_3G;
 622                 }
 623         } else {
 624                 /* Normal file */
 625                 ret = capture_ntfs_streams(root, ni, path, path_len,
 626                                            lookup_table, ntfs_vol_p,
 627                                            AT_DATA);
 628         }
 629         if (ret != 0)
 630                 return ret;
 631
 632         char _sd[1];
 633         char *sd = _sd;
 634         errno = 0;
 635         ret = ntfs_xattr_system_getxattr(&ctx, XATTR_NTFS_ACL,
 636                                          ni, dir_ni, sd,
 637                                          sizeof(sd));
 638         if (ret > sizeof(sd)) {
 639                 sd = alloca(ret);
 640                 ret = ntfs_xattr_system_getxattr(&ctx, XATTR_NTFS_ACL,
 641                                                  ni, dir_ni, sd, ret);
 642         }
 643         if (ret > 0) {
 644                 root->d_inode->i_security_id = sd_set_add_sd(sd_set, sd, ret);
 645                 if (root->d_inode->i_security_id == -1) {
 646                         ERROR("Out of memory");
 647                         return WIMLIB_ERR_NOMEM;
 648                 }
 649                 DEBUG("Added security ID = %u for `%s'",
 650                       root->d_inode->i_security_id, path);
 651                 ret = 0;
 652         } else if (ret < 0) {
 653                 ERROR_WITH_ERRNO("Failed to get security information from "
 654                                  "`%s'", path);
 655                 ret = WIMLIB_ERR_NTFS_3G;
 656         } else {
 657                 root->d_inode->i_security_id = -1;
 658                 DEBUG("No security ID for `%s'", path);
 659         }
 660         return ret;
 661 }
 662
 663 int build_dentry_tree_ntfs(struct wim_dentry **root_p,
 664                            const char *device,
 665                            struct wim_lookup_table *lookup_table,
 666                            struct wim_security_data *sd,
 667                            const struct capture_config *config,
 668                            int add_image_flags,
 669                            wimlib_progress_func_t progress_func,
 670                            void *extra_arg)
 671 {
 672         ntfs_volume *vol;
 673         ntfs_inode *root_ni;
 674         int ret;
 675         struct sd_set sd_set = {
 676                 .sd = sd,
 677                 .rb_root = {NULL},
 678         };
 679         ntfs_volume **ntfs_vol_p = extra_arg;
 680
 681         DEBUG("Mounting NTFS volume `%s' read-only", device);
 682
 683 #ifdef HAVE_NTFS_MNT_RDONLY
 684         /* NTFS-3g 2013 */
 685         vol = ntfs_mount(device, NTFS_MNT_RDONLY);
 686 #else
 687         /* NTFS-3g 2011, 2012 */
 688         vol = ntfs_mount(device, MS_RDONLY);
 689 #endif
 690         if (!vol) {
 691                 ERROR_WITH_ERRNO("Failed to mount NTFS volume `%s' read-only",
 692                                  device);
 693                 return WIMLIB_ERR_NTFS_3G;
 694         }
 695         ntfs_open_secure(vol);
 696
 697         /* We don't want to capture the special NTFS files such as $Bitmap.  Not
 698          * to be confused with "hidden" or "system" files which are real files
 699          * that we do need to capture.  */
 700         NVolClearShowSysFiles(vol);
 701
 702         DEBUG("Opening root NTFS dentry");
 703         root_ni = ntfs_inode_open(vol, FILE_root);
 704         if (!root_ni) {
 705                 ERROR_WITH_ERRNO("Failed to open root inode of NTFS volume "
 706                                  "`%s'", device);
 707                 ret = WIMLIB_ERR_NTFS_3G;
 708                 goto out;
 709         }
 710
 711         /* Currently we assume that all the UTF-8 paths fit into this length and
 712          * there is no check for overflow. */
 713         char *path = MALLOC(32768);
 714         if (!path) {
 715                 ERROR("Could not allocate memory for NTFS pathname");
 716                 ret = WIMLIB_ERR_NOMEM;
 717                 goto out_cleanup;
 718         }
 719
 720         path[0] = '/';
 721         path[1] = '\0';
 722         ret = build_dentry_tree_ntfs_recursive(root_p, NULL, root_ni, path, 1,
 723                                                FILE_NAME_POSIX, lookup_table,
 724                                                &sd_set, config, ntfs_vol_p,
 725                                                add_image_flags,
 726                                                progress_func);
 727 out_cleanup:
 728         FREE(path);
 729         ntfs_inode_close(root_ni);
 730         destroy_sd_set(&sd_set);
 731
 732 out:
 733         ntfs_index_ctx_put(vol->secure_xsii);
 734         ntfs_index_ctx_put(vol->secure_xsdh);
 735         ntfs_inode_close(vol->secure_ni);
 736
 737         if (ret) {
 738                 if (ntfs_umount(vol, FALSE) != 0) {
 739                         ERROR_WITH_ERRNO("Failed to unmount NTFS volume `%s'",
 740                                          device);
 741                         if (ret == 0)
 742                                 ret = WIMLIB_ERR_NTFS_3G;
 743                 }
 744         } else {
 745                 /* We need to leave the NTFS volume mounted so that we can read
 746                  * the NTFS files again when we are actually writing the WIM */
 747                 *ntfs_vol_p = vol;
 748         }
 749         return ret;
 750 }