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   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 #include "config.h"
  28 #include "wimlib_internal.h"
  29
  30
  31 #ifdef WITH_NTFS_3G
  32 #include "dentry.h"
  33 #include "lookup_table.h"
  34 #include "io.h"
  35 #include <ntfs-3g/layout.h>
  36 #include <ntfs-3g/acls.h>
  37 #include <ntfs-3g/attrib.h>
  38 #include <ntfs-3g/misc.h>
  39 #include <ntfs-3g/reparse.h>
  40 #include <ntfs-3g/security.h>
  41 #include <ntfs-3g/volume.h>
  42 #include <stdlib.h>
  43 #include <unistd.h>
  44 #include <errno.h>
  45
  46 extern int ntfs_inode_get_security(ntfs_inode *ni, u32 selection, char *buf,
  47                                    u32 buflen, u32 *psize);
  48
  49 extern int ntfs_inode_get_attributes(ntfs_inode *ni);
  50
  51 /* Structure that allows searching the security descriptors by SHA1 message
  52  * digest. */
  53 struct sd_set {
  54         struct wim_security_data *sd;
  55         struct sd_node *root;
  56 };
  57
  58 /* Binary tree node of security descriptors, indexed by the @hash field. */
  59 struct sd_node {
  60         int security_id;
  61         u8 hash[SHA1_HASH_SIZE];
  62         struct sd_node *left;
  63         struct sd_node *right;
  64 };
  65
  66 static void free_sd_tree(struct sd_node *root)
  67 {
  68         if (root) {
  69                 free_sd_tree(root->left);
  70                 free_sd_tree(root->right);
  71                 FREE(root);
  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->root);
  78 }
  79
  80 /* Inserts a a new node into the security descriptor index tree. */
  81 static void insert_sd_node(struct sd_node *new, struct sd_node *root)
  82 {
  83         int cmp = hashes_cmp(new->hash, root->hash);
  84         if (cmp < 0) {
  85                 if (root->left)
  86                         insert_sd_node(new, root->left);
  87                 else
  88                         root->left = new;
  89         } else if (cmp > 0) {
  90                 if (root->right)
  91                         insert_sd_node(new, root->right);
  92                 else
  93                         root->right = new;
  94         } else {
  95                 wimlib_assert(0);
  96         }
  97 }
  98
  99 /* Returns the security ID of the security data having a SHA1 message digest of
 100  * @hash in the security descriptor index tree rooted at @root.
 101  *
 102  * If not found, return -1. */
 103 static int lookup_sd(const u8 hash[SHA1_HASH_SIZE], struct sd_node *root)
 104 {
 105         int cmp;
 106         if (!root)
 107                 return -1;
 108         cmp = hashes_cmp(hash, root->hash);
 109         if (cmp < 0)
 110                 return lookup_sd(hash, root->left);
 111         else if (cmp > 0)
 112                 return lookup_sd(hash, root->right);
 113         else
 114                 return root->security_id;
 115 }
 116
 117 /*
 118  * Adds a security descriptor to the indexed security descriptor set as well as
 119  * the corresponding `struct wim_security_data', and returns the new security
 120  * ID; or, if there is an existing security descriptor that is the same, return
 121  * the security ID for it.  If a new security descriptor cannot be allocated,
 122  * return -1.
 123  */
 124 static int sd_set_add_sd(struct sd_set *sd_set, const char descriptor[],
 125                          size_t size)
 126 {
 127         u8 hash[SHA1_HASH_SIZE];
 128         int security_id;
 129         struct sd_node *new;
 130         u8 **descriptors;
 131         u64 *sizes;
 132         u8 *descr_copy;
 133         struct wim_security_data *sd;
 134
 135         sha1_buffer((const u8*)descriptor, size, hash);
 136
 137         security_id = lookup_sd(hash, sd_set->root);
 138         if (security_id >= 0)
 139                 return security_id;
 140
 141         new = MALLOC(sizeof(*new));
 142         if (!new)
 143                 goto out;
 144         descr_copy = MALLOC(size);
 145         if (!descr_copy)
 146                 goto out_free_node;
 147
 148         sd = sd_set->sd;
 149
 150         memcpy(descr_copy, descriptor, size);
 151         new->security_id = sd->num_entries;
 152         new->left = NULL;
 153         new->right = NULL;
 154         copy_hash(new->hash, hash);
 155
 156
 157         descriptors = REALLOC(sd->descriptors,
 158                               (sd->num_entries + 1) * sizeof(sd->descriptors[0]));
 159         if (!descriptors)
 160                 goto out_free_descr;
 161         sd->descriptors = descriptors;
 162         sizes = REALLOC(sd->sizes,
 163                         (sd->num_entries + 1) * sizeof(sd->sizes[0]));
 164         if (!sizes)
 165                 goto out_free_descr;
 166         sd->sizes = sizes;
 167         sd->descriptors[sd->num_entries] = descr_copy;
 168         sd->sizes[sd->num_entries] = size;
 169         sd->num_entries++;
 170         DEBUG("There are now %d security descriptors", sd->num_entries);
 171         sd->total_length += size + sizeof(sd->sizes[0]);
 172
 173         if (sd_set->root)
 174                 insert_sd_node(new, sd_set->root);
 175         else
 176                 sd_set->root = new;
 177         return new->security_id;
 178 out_free_descr:
 179         FREE(descr_copy);
 180 out_free_node:
 181         FREE(new);
 182 out:
 183         return -1;
 184 }
 185
 186 static inline ntfschar *attr_record_name(ATTR_RECORD *ar)
 187 {
 188         return (ntfschar*)((u8*)ar + le16_to_cpu(ar->name_offset));
 189 }
 190
 191 /* Calculates the SHA1 message digest of a NTFS attribute.
 192  *
 193  * @ni:  The NTFS inode containing the attribute.
 194  * @ar:  The ATTR_RECORD describing the attribute.
 195  * @md:  If successful, the returned SHA1 message digest.
 196  * @reparse_tag_ret:    Optional pointer into which the first 4 bytes of the
 197  *                              attribute will be written (to get the reparse
 198  *                              point ID)
 199  *
 200  * Return 0 on success or nonzero on error.
 201  */
 202 static int ntfs_attr_sha1sum(ntfs_inode *ni, ATTR_RECORD *ar,
 203                              u8 md[SHA1_HASH_SIZE],
 204                              u32 *reparse_tag_ret)
 205 {
 206         s64 pos = 0;
 207         s64 bytes_remaining;
 208         char buf[4096];
 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         sha1_init(&ctx);
 221
 222         DEBUG2("Calculating SHA1 message digest (%"PRIu64" bytes)",
 223                bytes_remaining);
 224
 225         while (bytes_remaining) {
 226                 s64 to_read = min(bytes_remaining, sizeof(buf));
 227                 if (ntfs_attr_pread(na, pos, to_read, buf) != to_read) {
 228                         ERROR_WITH_ERRNO("Error reading NTFS attribute");
 229                         return WIMLIB_ERR_NTFS_3G;
 230                 }
 231                 if (bytes_remaining == na->data_size && reparse_tag_ret)
 232                         *reparse_tag_ret = le32_to_cpu(*(u32*)buf);
 233                 sha1_update(&ctx, buf, to_read);
 234                 pos += to_read;
 235                 bytes_remaining -= to_read;
 236         }
 237         sha1_final(md, &ctx);
 238         ntfs_attr_close(na);
 239         return 0;
 240 }
 241
 242 /* Load the streams from a WIM file or reparse point in the NTFS volume into the
 243  * WIM lookup table */
 244 static int capture_ntfs_streams(struct dentry *dentry, ntfs_inode *ni,
 245                                 char path[], size_t path_len,
 246                                 struct lookup_table *lookup_table,
 247                                 ntfs_volume **ntfs_vol_p,
 248                                 ATTR_TYPES type)
 249 {
 250
 251         ntfs_attr_search_ctx *actx;
 252         u8 attr_hash[SHA1_HASH_SIZE];
 253         struct ntfs_location *ntfs_loc = NULL;
 254         int ret = 0;
 255         struct lookup_table_entry *lte;
 256
 257         DEBUG2("Capturing NTFS data streams from `%s'", path);
 258
 259         /* Get context to search the streams of the NTFS file. */
 260         actx = ntfs_attr_get_search_ctx(ni, NULL);
 261         if (!actx) {
 262                 ERROR_WITH_ERRNO("Cannot get NTFS attribute search "
 263                                  "context");
 264                 return WIMLIB_ERR_NTFS_3G;
 265         }
 266
 267         /* Capture each data stream or reparse data stream. */
 268         while (!ntfs_attr_lookup(type, NULL, 0,
 269                                  CASE_SENSITIVE, 0, NULL, 0, actx))
 270         {
 271                 char *stream_name_utf8;
 272                 size_t stream_name_utf16_len;
 273                 u32 reparse_tag;
 274                 u64 data_size = ntfs_get_attribute_value_length(actx->attr);
 275                 u64 name_length = actx->attr->name_length;
 276
 277                 if (data_size == 0) {
 278                         if (errno != 0) {
 279                                 ERROR_WITH_ERRNO("Failed to get size of attribute of "
 280                                                  "`%s'", path);
 281                                 ret = WIMLIB_ERR_NTFS_3G;
 282                                 goto out_put_actx;
 283                         }
 284                         /* Empty stream.  No lookup table entry is needed. */
 285                         lte = NULL;
 286                 } else {
 287                         if (type == AT_REPARSE_POINT && data_size < 8) {
 288                                 ERROR("`%s': reparse point buffer too small");
 289                                 ret = WIMLIB_ERR_NTFS_3G;
 290                                 goto out_put_actx;
 291                         }
 292                         /* Checksum the stream. */
 293                         ret = ntfs_attr_sha1sum(ni, actx->attr, attr_hash, &reparse_tag);
 294                         if (ret != 0)
 295                                 goto out_put_actx;
 296
 297                         /* Make a lookup table entry for the stream, or use an existing
 298                          * one if there's already an identical stream. */
 299                         lte = __lookup_resource(lookup_table, attr_hash);
 300                         ret = WIMLIB_ERR_NOMEM;
 301                         if (lte) {
 302                                 lte->refcnt++;
 303                         } else {
 304                                 ntfs_loc = CALLOC(1, sizeof(*ntfs_loc));
 305                                 if (!ntfs_loc)
 306                                         goto out_put_actx;
 307                                 ntfs_loc->ntfs_vol_p = ntfs_vol_p;
 308                                 ntfs_loc->path_utf8 = MALLOC(path_len + 1);
 309                                 if (!ntfs_loc->path_utf8)
 310                                         goto out_free_ntfs_loc;
 311                                 memcpy(ntfs_loc->path_utf8, path, path_len + 1);
 312                                 if (name_length) {
 313                                         ntfs_loc->stream_name_utf16 = MALLOC(name_length * 2);
 314                                         if (!ntfs_loc->stream_name_utf16)
 315                                                 goto out_free_ntfs_loc;
 316                                         memcpy(ntfs_loc->stream_name_utf16,
 317                                                attr_record_name(actx->attr),
 318                                                actx->attr->name_length * 2);
 319                                         ntfs_loc->stream_name_utf16_num_chars = name_length;
 320                                 }
 321
 322                                 lte = new_lookup_table_entry();
 323                                 if (!lte)
 324                                         goto out_free_ntfs_loc;
 325                                 lte->ntfs_loc = ntfs_loc;
 326                                 lte->resource_location = RESOURCE_IN_NTFS_VOLUME;
 327                                 if (type == AT_REPARSE_POINT) {
 328                                         dentry->reparse_tag = reparse_tag;
 329                                         ntfs_loc->is_reparse_point = true;
 330                                         lte->resource_entry.original_size = data_size - 8;
 331                                         lte->resource_entry.size = data_size - 8;
 332                                 } else {
 333                                         ntfs_loc->is_reparse_point = false;
 334                                         lte->resource_entry.original_size = data_size;
 335                                         lte->resource_entry.size = data_size;
 336                                 }
 337                                 ntfs_loc = NULL;
 338                                 DEBUG("Add resource for `%s' (size = %zu)",
 339                                       dentry->file_name_utf8,
 340                                       lte->resource_entry.original_size);
 341                                 copy_hash(lte->hash, attr_hash);
 342                                 lookup_table_insert(lookup_table, lte);
 343                         }
 344                 }
 345                 if (name_length == 0) {
 346                         /* Unnamed data stream.  Put the reference to it in the
 347                          * dentry. */
 348                         if (dentry->lte) {
 349                                 ERROR("Found two un-named data streams for "
 350                                       "`%s'", path);
 351                                 ret = WIMLIB_ERR_NTFS_3G;
 352                                 goto out_free_lte;
 353                         }
 354                         dentry->lte = lte;
 355                 } else {
 356                         /* Named data stream.  Put the reference to it in the
 357                          * alternate data stream entries */
 358                         struct ads_entry *new_ads_entry;
 359                         size_t stream_name_utf8_len;
 360                         stream_name_utf8 = utf16_to_utf8((const char*)attr_record_name(actx->attr),
 361                                                          name_length * 2,
 362                                                          &stream_name_utf8_len);
 363                         if (!stream_name_utf8)
 364                                 goto out_free_lte;
 365                         new_ads_entry = dentry_add_ads(dentry, stream_name_utf8);
 366                         FREE(stream_name_utf8);
 367                         if (!new_ads_entry)
 368                                 goto out_free_lte;
 369
 370                         wimlib_assert(new_ads_entry->stream_name_len == name_length * 2);
 371
 372                         new_ads_entry->lte = lte;
 373                 }
 374         }
 375         ret = 0;
 376         goto out_put_actx;
 377 out_free_lte:
 378         free_lookup_table_entry(lte);
 379 out_free_ntfs_loc:
 380         if (ntfs_loc) {
 381                 FREE(ntfs_loc->path_utf8);
 382                 FREE(ntfs_loc->stream_name_utf16);
 383                 FREE(ntfs_loc);
 384         }
 385 out_put_actx:
 386         ntfs_attr_put_search_ctx(actx);
 387         if (ret == 0)
 388                 DEBUG2("Successfully captured NTFS streams from `%s'", path);
 389         else
 390                 ERROR("Failed to capture NTFS streams from `%s", path);
 391         return ret;
 392 }
 393
 394 struct readdir_ctx {
 395         struct dentry       *parent;
 396         ntfs_inode          *dir_ni;
 397         char                *path;
 398         size_t               path_len;
 399         struct lookup_table *lookup_table;
 400         struct sd_set       *sd_set;
 401         const struct capture_config *config;
 402         ntfs_volume        **ntfs_vol_p;
 403         int                  flags;
 404 };
 405
 406 static int
 407 build_dentry_tree_ntfs_recursive(struct dentry **root_p, ntfs_inode *ni,
 408                                  char path[], size_t path_len,
 409                                  struct lookup_table *lookup_table,
 410                                  struct sd_set *sd_set,
 411                                  const struct capture_config *config,
 412                                  ntfs_volume **ntfs_vol_p,
 413                                  int flags);
 414
 415 static int wim_ntfs_capture_filldir(void *dirent, const ntfschar *name,
 416                                     const int name_len, const int name_type,
 417                                     const s64 pos, const MFT_REF mref,
 418                                     const unsigned dt_type)
 419 {
 420         struct readdir_ctx *ctx;
 421         size_t utf8_name_len;
 422         char *utf8_name;
 423         struct dentry *child = NULL;
 424         int ret;
 425         size_t path_len;
 426
 427         if (name_type == FILE_NAME_DOS)
 428                 return 0;
 429
 430         ret = -1;
 431
 432         utf8_name = utf16_to_utf8((const char*)name, name_len * 2,
 433                                   &utf8_name_len);
 434         if (!utf8_name)
 435                 goto out;
 436
 437         if (utf8_name[0] == '.' &&
 438              (utf8_name[1] == '\0' ||
 439               (utf8_name[1] == '.' && utf8_name[2] == '\0'))) {
 440                 ret = 0;
 441                 goto out_free_utf8_name;
 442         }
 443
 444         ctx = dirent;
 445
 446         ntfs_inode *ni = ntfs_inode_open(ctx->dir_ni->vol, mref);
 447         if (!ni) {
 448                 ERROR_WITH_ERRNO("Failed to open NTFS inode");
 449                 ret = 1;
 450         }
 451         path_len = ctx->path_len;
 452         if (path_len != 1)
 453                 ctx->path[path_len++] = '/';
 454         memcpy(ctx->path + path_len, utf8_name, utf8_name_len + 1);
 455         path_len += utf8_name_len;
 456         ret = build_dentry_tree_ntfs_recursive(&child, ni, ctx->path, path_len,
 457                                                ctx->lookup_table, ctx->sd_set,
 458                                                ctx->config, ctx->ntfs_vol_p,
 459                                                ctx->flags);
 460
 461         if (child)
 462                 link_dentry(child, ctx->parent);
 463
 464         ntfs_inode_close(ni);
 465 out_free_utf8_name:
 466         FREE(utf8_name);
 467 out:
 468         return ret;
 469 }
 470
 471 /* Recursively build a WIM dentry tree corresponding to a NTFS volume.
 472  * At the same time, update the WIM lookup table with lookup table entries for
 473  * the NTFS streams, and build an array of security descriptors.
 474  */
 475 static int build_dentry_tree_ntfs_recursive(struct dentry **root_p,
 476                                             ntfs_inode *ni,
 477                                             char path[],
 478                                             size_t path_len,
 479                                             struct lookup_table *lookup_table,
 480                                             struct sd_set *sd_set,
 481                                             const struct capture_config *config,
 482                                             ntfs_volume **ntfs_vol_p,
 483                                             int flags)
 484 {
 485         u32 attributes;
 486         int mrec_flags;
 487         u32 sd_size = 0;
 488         int ret = 0;
 489         struct dentry *root;
 490
 491         mrec_flags = ni->mrec->flags;
 492         attributes = ntfs_inode_get_attributes(ni);
 493
 494         if (exclude_path(path, config, false)) {
 495                 if (flags & WIMLIB_ADD_IMAGE_FLAG_VERBOSE) {
 496                         const char *file_type;
 497                         if (attributes & MFT_RECORD_IS_DIRECTORY)
 498                                 file_type = "directory";
 499                         else
 500                                 file_type = "file";
 501                         printf("Excluding %s `%s' from capture\n",
 502                                file_type, path);
 503                 }
 504                 *root_p = NULL;
 505                 return 0;
 506         }
 507
 508         if (flags & WIMLIB_ADD_IMAGE_FLAG_VERBOSE)
 509                 printf("Scanning `%s'\n", path);
 510
 511         root = new_dentry(path_basename(path));
 512         if (!root)
 513                 return WIMLIB_ERR_NOMEM;
 514
 515         *root_p = root;
 516         root->creation_time    = le64_to_cpu(ni->creation_time);
 517         root->last_write_time  = le64_to_cpu(ni->last_data_change_time);
 518         root->last_access_time = le64_to_cpu(ni->last_access_time);
 519         root->attributes       = le32_to_cpu(attributes);
 520         root->link_group_id    = ni->mft_no;
 521         root->resolved         = true;
 522
 523         if (attributes & FILE_ATTR_REPARSE_POINT) {
 524                 /* Junction point, symbolic link, or other reparse point */
 525                 ret = capture_ntfs_streams(root, ni, path, path_len,
 526                                            lookup_table, ntfs_vol_p,
 527                                            AT_REPARSE_POINT);
 528         } else if (mrec_flags & MFT_RECORD_IS_DIRECTORY) {
 529
 530                 /* Normal directory */
 531                 s64 pos = 0;
 532                 struct readdir_ctx ctx = {
 533                         .parent       = root,
 534                         .dir_ni       = ni,
 535                         .path         = path,
 536                         .path_len     = path_len,
 537                         .lookup_table = lookup_table,
 538                         .sd_set       = sd_set,
 539                         .config       = config,
 540                         .ntfs_vol_p   = ntfs_vol_p,
 541                         .flags        = flags,
 542                 };
 543                 ret = ntfs_readdir(ni, &pos, &ctx, wim_ntfs_capture_filldir);
 544                 if (ret != 0) {
 545                         ERROR_WITH_ERRNO("ntfs_readdir()");
 546                         ret = WIMLIB_ERR_NTFS_3G;
 547                 }
 548         } else {
 549                 /* Normal file */
 550                 ret = capture_ntfs_streams(root, ni, path, path_len,
 551                                            lookup_table, ntfs_vol_p,
 552                                            AT_DATA);
 553         }
 554         if (ret != 0)
 555                 return ret;
 556
 557         ret = ntfs_inode_get_security(ni,
 558                                       OWNER_SECURITY_INFORMATION |
 559                                       GROUP_SECURITY_INFORMATION |
 560                                       DACL_SECURITY_INFORMATION  |
 561                                       SACL_SECURITY_INFORMATION,
 562                                       NULL, 0, &sd_size);
 563         char sd[sd_size];
 564         ret = ntfs_inode_get_security(ni,
 565                                       OWNER_SECURITY_INFORMATION |
 566                                       GROUP_SECURITY_INFORMATION |
 567                                       DACL_SECURITY_INFORMATION  |
 568                                       SACL_SECURITY_INFORMATION,
 569                                       sd, sd_size, &sd_size);
 570         if (ret == 0) {
 571                 ERROR_WITH_ERRNO("Failed to get security information from "
 572                                  "`%s'", path);
 573                 ret = WIMLIB_ERR_NTFS_3G;
 574         } else {
 575                 if (ret > 0) {
 576                         /*print_security_descriptor(sd, sd_size);*/
 577                         root->security_id = sd_set_add_sd(sd_set, sd, sd_size);
 578                         if (root->security_id == -1) {
 579                                 ERROR("Out of memory");
 580                                 return WIMLIB_ERR_NOMEM;
 581                         }
 582                         DEBUG("Added security ID = %u for `%s'",
 583                               root->security_id, path);
 584                 } else {
 585                         root->security_id = -1;
 586                         DEBUG("No security ID for `%s'", path);
 587                 }
 588                 ret = 0;
 589         }
 590         return ret;
 591 }
 592
 593 static int build_dentry_tree_ntfs(struct dentry **root_p,
 594                                   const char *device,
 595                                   struct lookup_table *lookup_table,
 596                                   struct wim_security_data *sd,
 597                                   const struct capture_config *config,
 598                                   int flags,
 599                                   void *extra_arg)
 600 {
 601         ntfs_volume *vol;
 602         ntfs_inode *root_ni;
 603         int ret = 0;
 604         struct sd_set sd_set = {
 605                 .sd = sd,
 606                 .root = NULL,
 607         };
 608         ntfs_volume **ntfs_vol_p = extra_arg;
 609
 610         DEBUG("Mounting NTFS volume `%s' read-only", device);
 611
 612         vol = ntfs_mount(device, MS_RDONLY);
 613         if (!vol) {
 614                 ERROR_WITH_ERRNO("Failed to mount NTFS volume `%s' read-only",
 615                                  device);
 616                 return WIMLIB_ERR_NTFS_3G;
 617         }
 618         ntfs_open_secure(vol);
 619
 620         /* We don't want to capture the special NTFS files such as $Bitmap.  Not
 621          * to be confused with "hidden" or "system" files which are real files
 622          * that we do need to capture.  */
 623         NVolClearShowSysFiles(vol);
 624
 625         DEBUG("Opening root NTFS dentry");
 626         root_ni = ntfs_inode_open(vol, FILE_root);
 627         if (!root_ni) {
 628                 ERROR_WITH_ERRNO("Failed to open root inode of NTFS volume "
 629                                  "`%s'", device);
 630                 ret = WIMLIB_ERR_NTFS_3G;
 631                 goto out;
 632         }
 633
 634         /* Currently we assume that all the UTF-8 paths fit into this length and
 635          * there is no check for overflow. */
 636         char *path = MALLOC(32768);
 637         if (!path) {
 638                 ERROR("Could not allocate memory for NTFS pathname");
 639                 goto out_cleanup;
 640         }
 641
 642         path[0] = '/';
 643         path[1] = '\0';
 644         ret = build_dentry_tree_ntfs_recursive(root_p, root_ni, path, 1,
 645                                                lookup_table, &sd_set,
 646                                                config, ntfs_vol_p, flags);
 647 out_cleanup:
 648         FREE(path);
 649         ntfs_inode_close(root_ni);
 650         destroy_sd_set(&sd_set);
 651
 652 out:
 653         if (ret) {
 654                 if (ntfs_umount(vol, FALSE) != 0) {
 655                         ERROR_WITH_ERRNO("Failed to unmount NTFS volume `%s'",
 656                                          device);
 657                         if (ret == 0)
 658                                 ret = WIMLIB_ERR_NTFS_3G;
 659                 }
 660         } else {
 661                 /* We need to leave the NTFS volume mounted so that we can read
 662                  * the NTFS files again when we are actually writing the WIM */
 663                 *ntfs_vol_p = vol;
 664         }
 665         return ret;
 666 }
 667
 668
 669
 670 WIMLIBAPI int wimlib_add_image_from_ntfs_volume(WIMStruct *w,
 671                                                 const char *device,
 672                                                 const char *name,
 673                                                 const char *config_str,
 674                                                 size_t config_len,
 675                                                 int flags)
 676 {
 677         if (flags & (WIMLIB_ADD_IMAGE_FLAG_DEREFERENCE)) {
 678                 ERROR("Cannot dereference files when capturing directly from NTFS");
 679                 return WIMLIB_ERR_INVALID_PARAM;
 680         }
 681         return do_add_image(w, device, name, config_str, config_len, flags,
 682                             build_dentry_tree_ntfs, &w->ntfs_vol);
 683 }
 684
 685 #else /* WITH_NTFS_3G */
 686 WIMLIBAPI int wimlib_add_image_from_ntfs_volume(WIMStruct *w,
 687                                                 const char *device,
 688                                                 const char *name,
 689                                                 const char *config_str,
 690                                                 size_t config_len,
 691                                                 int flags)
 692 {
 693         ERROR("wimlib was compiled without support for NTFS-3g, so");
 694         ERROR("we cannot capture a WIM image directly from a NTFS volume");
 695         return WIMLIB_ERR_UNSUPPORTED;
 696 }
 697 #endif /* WITH_NTFS_3G */