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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
  28 #include "config.h"
  29
  30 #ifdef WITH_NTFS_3G
  31 #include <ntfs-3g/endians.h>
  32 #include <ntfs-3g/types.h>
  33 #endif
  34
  35 #include "wimlib_internal.h"
  36
  37
  38 #ifdef WITH_NTFS_3G
  39 #include "dentry.h"
  40 #include "lookup_table.h"
  41 #include "io.h"
  42 #include <ntfs-3g/layout.h>
  43 #include <ntfs-3g/acls.h>
  44 #include <ntfs-3g/attrib.h>
  45 #include <ntfs-3g/misc.h>
  46 #include <ntfs-3g/reparse.h>
  47 #include <ntfs-3g/security.h> /* security.h before xattrs.h */
  48 #include <ntfs-3g/xattrs.h>
  49 #include <ntfs-3g/volume.h>
  50 #include <stdlib.h>
  51 #include <unistd.h>
  52 #include <errno.h>
  53
  54 /* Structure that allows searching the security descriptors by SHA1 message
  55  * digest. */
  56 struct sd_set {
  57         struct wim_security_data *sd;
  58         struct sd_node *root;
  59 };
  60
  61 /* Binary tree node of security descriptors, indexed by the @hash field. */
  62 struct sd_node {
  63         int security_id;
  64         u8 hash[SHA1_HASH_SIZE];
  65         struct sd_node *left;
  66         struct sd_node *right;
  67 };
  68
  69 static void free_sd_tree(struct sd_node *root)
  70 {
  71         if (root) {
  72                 free_sd_tree(root->left);
  73                 free_sd_tree(root->right);
  74                 FREE(root);
  75         }
  76 }
  77 /* Frees a security descriptor index set. */
  78 static void destroy_sd_set(struct sd_set *sd_set)
  79 {
  80         free_sd_tree(sd_set->root);
  81 }
  82
  83 /* Inserts a a new node into the security descriptor index tree. */
  84 static void insert_sd_node(struct sd_node *new, struct sd_node *root)
  85 {
  86         int cmp = hashes_cmp(new->hash, root->hash);
  87         if (cmp < 0) {
  88                 if (root->left)
  89                         insert_sd_node(new, root->left);
  90                 else
  91                         root->left = new;
  92         } else if (cmp > 0) {
  93                 if (root->right)
  94                         insert_sd_node(new, root->right);
  95                 else
  96                         root->right = new;
  97         } else {
  98                 wimlib_assert(0);
  99         }
 100 }
 101
 102 /* Returns the security ID of the security data having a SHA1 message digest of
 103  * @hash in the security descriptor index tree rooted at @root.
 104  *
 105  * If not found, return -1. */
 106 static int lookup_sd(const u8 hash[SHA1_HASH_SIZE], struct sd_node *root)
 107 {
 108         int cmp;
 109         if (!root)
 110                 return -1;
 111         cmp = hashes_cmp(hash, root->hash);
 112         if (cmp < 0)
 113                 return lookup_sd(hash, root->left);
 114         else if (cmp > 0)
 115                 return lookup_sd(hash, root->right);
 116         else
 117                 return root->security_id;
 118 }
 119
 120 /*
 121  * Adds a security descriptor to the indexed security descriptor set as well as
 122  * the corresponding `struct wim_security_data', and returns the new security
 123  * ID; or, if there is an existing security descriptor that is the same, return
 124  * the security ID for it.  If a new security descriptor cannot be allocated,
 125  * return -1.
 126  */
 127 static int sd_set_add_sd(struct sd_set *sd_set, const char descriptor[],
 128                          size_t size)
 129 {
 130         u8 hash[SHA1_HASH_SIZE];
 131         int security_id;
 132         struct sd_node *new;
 133         u8 **descriptors;
 134         u64 *sizes;
 135         u8 *descr_copy;
 136         struct wim_security_data *sd;
 137
 138         sha1_buffer((const u8*)descriptor, size, hash);
 139
 140         security_id = lookup_sd(hash, sd_set->root);
 141         if (security_id >= 0)
 142                 return security_id;
 143
 144         new = MALLOC(sizeof(*new));
 145         if (!new)
 146                 goto out;
 147         descr_copy = MALLOC(size);
 148         if (!descr_copy)
 149                 goto out_free_node;
 150
 151         sd = sd_set->sd;
 152
 153         memcpy(descr_copy, descriptor, size);
 154         new->security_id = sd->num_entries;
 155         new->left = NULL;
 156         new->right = NULL;
 157         copy_hash(new->hash, hash);
 158
 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
 176         if (sd_set->root)
 177                 insert_sd_node(new, sd_set->root);
 178         else
 179                 sd_set->root = new;
 180         return new->security_id;
 181 out_free_descr:
 182         FREE(descr_copy);
 183 out_free_node:
 184         FREE(new);
 185 out:
 186         return -1;
 187 }
 188
 189 static inline ntfschar *attr_record_name(ATTR_RECORD *ar)
 190 {
 191         return (ntfschar*)((u8*)ar + le16_to_cpu(ar->name_offset));
 192 }
 193
 194 /* Calculates the SHA1 message digest of a NTFS attribute.
 195  *
 196  * @ni:  The NTFS inode containing the attribute.
 197  * @ar:  The ATTR_RECORD describing the attribute.
 198  * @md:  If successful, the returned SHA1 message digest.
 199  * @reparse_tag_ret:    Optional pointer into which the first 4 bytes of the
 200  *                              attribute will be written (to get the reparse
 201  *                              point ID)
 202  *
 203  * Return 0 on success or nonzero on error.
 204  */
 205 static int ntfs_attr_sha1sum(ntfs_inode *ni, ATTR_RECORD *ar,
 206                              u8 md[SHA1_HASH_SIZE],
 207                              u32 *reparse_tag_ret)
 208 {
 209         s64 pos = 0;
 210         s64 bytes_remaining;
 211         char buf[4096];
 212         ntfs_attr *na;
 213         SHA_CTX ctx;
 214
 215         na = ntfs_attr_open(ni, ar->type, attr_record_name(ar),
 216                             ar->name_length);
 217         if (!na) {
 218                 ERROR_WITH_ERRNO("Failed to open NTFS attribute");
 219                 return WIMLIB_ERR_NTFS_3G;
 220         }
 221
 222         bytes_remaining = na->data_size;
 223         sha1_init(&ctx);
 224
 225         DEBUG2("Calculating SHA1 message digest (%"PRIu64" bytes)",
 226                bytes_remaining);
 227
 228         while (bytes_remaining) {
 229                 s64 to_read = min(bytes_remaining, sizeof(buf));
 230                 if (ntfs_attr_pread(na, pos, to_read, buf) != to_read) {
 231                         ERROR_WITH_ERRNO("Error reading NTFS attribute");
 232                         return WIMLIB_ERR_NTFS_3G;
 233                 }
 234                 if (bytes_remaining == na->data_size && reparse_tag_ret)
 235                         *reparse_tag_ret = le32_to_cpu(*(u32*)buf);
 236                 sha1_update(&ctx, buf, to_read);
 237                 pos += to_read;
 238                 bytes_remaining -= to_read;
 239         }
 240         sha1_final(md, &ctx);
 241         ntfs_attr_close(na);
 242         return 0;
 243 }
 244
 245 /* Load the streams from a WIM file or reparse point in the NTFS volume into the
 246  * WIM lookup table */
 247 static int capture_ntfs_streams(struct dentry *dentry, ntfs_inode *ni,
 248                                 char path[], size_t path_len,
 249                                 struct lookup_table *lookup_table,
 250                                 ntfs_volume **ntfs_vol_p,
 251                                 ATTR_TYPES type)
 252 {
 253         ntfs_attr_search_ctx *actx;
 254         u8 attr_hash[SHA1_HASH_SIZE];
 255         struct ntfs_location *ntfs_loc = NULL;
 256         int ret = 0;
 257         struct lookup_table_entry *lte;
 258
 259         DEBUG2("Capturing NTFS data streams from `%s'", path);
 260
 261         /* Get context to search the streams of the NTFS file. */
 262         actx = ntfs_attr_get_search_ctx(ni, NULL);
 263         if (!actx) {
 264                 ERROR_WITH_ERRNO("Cannot get NTFS attribute search "
 265                                  "context");
 266                 return WIMLIB_ERR_NTFS_3G;
 267         }
 268
 269         /* Capture each data stream or reparse data stream. */
 270         while (!ntfs_attr_lookup(type, NULL, 0,
 271                                  CASE_SENSITIVE, 0, NULL, 0, actx))
 272         {
 273                 char *stream_name_utf8;
 274                 size_t stream_name_utf16_len;
 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, &reparse_tag);
 297                         if (ret != 0)
 298                                 goto out_put_actx;
 299
 300                         /* Make a lookup table entry for the stream, or use an existing
 301                          * one if there's already an identical stream. */
 302                         lte = __lookup_resource(lookup_table, attr_hash);
 303                         ret = WIMLIB_ERR_NOMEM;
 304                         if (lte) {
 305                                 lte->refcnt++;
 306                         } else {
 307                                 ntfs_loc = CALLOC(1, sizeof(*ntfs_loc));
 308                                 if (!ntfs_loc)
 309                                         goto out_put_actx;
 310                                 ntfs_loc->ntfs_vol_p = ntfs_vol_p;
 311                                 ntfs_loc->path_utf8 = MALLOC(path_len + 1);
 312                                 if (!ntfs_loc->path_utf8)
 313                                         goto out_free_ntfs_loc;
 314                                 memcpy(ntfs_loc->path_utf8, path, path_len + 1);
 315                                 if (name_length) {
 316                                         ntfs_loc->stream_name_utf16 = MALLOC(name_length * 2);
 317                                         if (!ntfs_loc->stream_name_utf16)
 318                                                 goto out_free_ntfs_loc;
 319                                         memcpy(ntfs_loc->stream_name_utf16,
 320                                                attr_record_name(actx->attr),
 321                                                actx->attr->name_length * 2);
 322                                         ntfs_loc->stream_name_utf16_num_chars = name_length;
 323                                 }
 324
 325                                 lte = new_lookup_table_entry();
 326                                 if (!lte)
 327                                         goto out_free_ntfs_loc;
 328                                 lte->ntfs_loc = ntfs_loc;
 329                                 lte->resource_location = RESOURCE_IN_NTFS_VOLUME;
 330                                 if (type == AT_REPARSE_POINT) {
 331                                         dentry->d_inode->reparse_tag = reparse_tag;
 332                                         ntfs_loc->is_reparse_point = true;
 333                                         lte->resource_entry.original_size = data_size - 8;
 334                                         lte->resource_entry.size = data_size - 8;
 335                                 } else {
 336                                         ntfs_loc->is_reparse_point = false;
 337                                         lte->resource_entry.original_size = data_size;
 338                                         lte->resource_entry.size = data_size;
 339                                 }
 340                                 ntfs_loc = NULL;
 341                                 DEBUG("Add resource for `%s' (size = %zu)",
 342                                       dentry->file_name_utf8,
 343                                       lte->resource_entry.original_size);
 344                                 copy_hash(lte->hash, attr_hash);
 345                                 lookup_table_insert(lookup_table, lte);
 346                         }
 347                 }
 348                 if (name_length == 0) {
 349                         /* Unnamed data stream.  Put the reference to it in the
 350                          * dentry's inode. */
 351                         if (dentry->d_inode->lte) {
 352                                 ERROR("Found two un-named data streams for "
 353                                       "`%s'", path);
 354                                 ret = WIMLIB_ERR_NTFS_3G;
 355                                 goto out_free_lte;
 356                         }
 357                         dentry->d_inode->lte = lte;
 358                 } else {
 359                         /* Named data stream.  Put the reference to it in the
 360                          * alternate data stream entries */
 361                         struct ads_entry *new_ads_entry;
 362                         size_t stream_name_utf8_len;
 363                         stream_name_utf8 = utf16_to_utf8((const char*)attr_record_name(actx->attr),
 364                                                          name_length * 2,
 365                                                          &stream_name_utf8_len);
 366                         if (!stream_name_utf8)
 367                                 goto out_free_lte;
 368                         new_ads_entry = inode_add_ads(dentry->d_inode, stream_name_utf8);
 369                         FREE(stream_name_utf8);
 370                         if (!new_ads_entry)
 371                                 goto out_free_lte;
 372
 373                         wimlib_assert(new_ads_entry->stream_name_len == name_length * 2);
 374
 375                         new_ads_entry->lte = lte;
 376                 }
 377         }
 378         ret = 0;
 379         goto out_put_actx;
 380 out_free_lte:
 381         free_lookup_table_entry(lte);
 382 out_free_ntfs_loc:
 383         if (ntfs_loc) {
 384                 FREE(ntfs_loc->path_utf8);
 385                 FREE(ntfs_loc->stream_name_utf16);
 386                 FREE(ntfs_loc);
 387         }
 388 out_put_actx:
 389         ntfs_attr_put_search_ctx(actx);
 390         if (ret == 0)
 391                 DEBUG2("Successfully captured NTFS streams from `%s'", path);
 392         else
 393                 ERROR("Failed to capture NTFS streams from `%s", path);
 394         return ret;
 395 }
 396
 397 struct readdir_ctx {
 398         struct dentry       *parent;
 399         ntfs_inode          *dir_ni;
 400         char                *path;
 401         size_t               path_len;
 402         struct lookup_table *lookup_table;
 403         struct sd_set       *sd_set;
 404         const struct capture_config *config;
 405         ntfs_volume        **ntfs_vol_p;
 406         int                  flags;
 407 };
 408
 409 static int
 410 build_dentry_tree_ntfs_recursive(struct dentry **root_p, ntfs_inode *dir_ni,
 411                                  ntfs_inode *ni, char path[], size_t path_len,
 412                                  int name_type,
 413                                  struct lookup_table *lookup_table,
 414                                  struct sd_set *sd_set,
 415                                  const struct capture_config *config,
 416                                  ntfs_volume **ntfs_vol_p,
 417                                  int flags);
 418
 419 static int wim_ntfs_capture_filldir(void *dirent, const ntfschar *name,
 420                                     const int name_len, const int name_type,
 421                                     const s64 pos, const MFT_REF mref,
 422                                     const unsigned dt_type)
 423 {
 424         struct readdir_ctx *ctx;
 425         size_t utf8_name_len;
 426         char *utf8_name;
 427         struct dentry *child = NULL;
 428         int ret;
 429         size_t path_len;
 430
 431         if (name_type == FILE_NAME_DOS)
 432                 return 0;
 433
 434         ret = -1;
 435
 436         utf8_name = utf16_to_utf8((const char*)name, name_len * 2,
 437                                   &utf8_name_len);
 438         if (!utf8_name)
 439                 goto out;
 440
 441         if (utf8_name[0] == '.' &&
 442              (utf8_name[1] == '\0' ||
 443               (utf8_name[1] == '.' && utf8_name[2] == '\0'))) {
 444                 ret = 0;
 445                 goto out_free_utf8_name;
 446         }
 447
 448         ctx = dirent;
 449
 450         ntfs_inode *ni = ntfs_inode_open(ctx->dir_ni->vol, mref);
 451         if (!ni) {
 452                 ERROR_WITH_ERRNO("Failed to open NTFS inode");
 453                 goto out_free_utf8_name;
 454         }
 455         path_len = ctx->path_len;
 456         if (path_len != 1)
 457                 ctx->path[path_len++] = '/';
 458         memcpy(ctx->path + path_len, utf8_name, utf8_name_len + 1);
 459         path_len += utf8_name_len;
 460         ret = build_dentry_tree_ntfs_recursive(&child, ctx->dir_ni,
 461                                                ni, ctx->path, path_len, name_type,
 462                                                ctx->lookup_table, ctx->sd_set,
 463                                                ctx->config, ctx->ntfs_vol_p,
 464                                                ctx->flags);
 465
 466         if (child)
 467                 link_dentry(child, ctx->parent);
 468
 469         ntfs_inode_close(ni);
 470 out_free_utf8_name:
 471         FREE(utf8_name);
 472 out:
 473         return ret;
 474 }
 475
 476 static int change_dentry_short_name(struct dentry *dentry,
 477                                     const char short_name_utf8[],
 478                                     int short_name_utf8_len)
 479 {
 480         size_t short_name_utf16_len;
 481         char *short_name_utf16;
 482         short_name_utf16 = utf8_to_utf16(short_name_utf8, short_name_utf8_len,
 483                                          &short_name_utf16_len);
 484         if (!short_name_utf16) {
 485                 ERROR_WITH_ERRNO("Failed to convert short name to UTF-16");
 486                 return WIMLIB_ERR_NOMEM;
 487         }
 488         dentry->short_name = short_name_utf16;
 489         dentry->short_name_len = short_name_utf16_len;
 490         return 0;
 491 }
 492
 493 /* Recursively build a WIM dentry tree corresponding to a NTFS volume.
 494  * At the same time, update the WIM lookup table with lookup table entries for
 495  * the NTFS streams, and build an array of security descriptors.
 496  */
 497 static int build_dentry_tree_ntfs_recursive(struct dentry **root_p,
 498                                             ntfs_inode *dir_ni,
 499                                             ntfs_inode *ni,
 500                                             char path[],
 501                                             size_t path_len,
 502                                             int name_type,
 503                                             struct lookup_table *lookup_table,
 504                                             struct sd_set *sd_set,
 505                                             const struct capture_config *config,
 506                                             ntfs_volume **ntfs_vol_p,
 507                                             int flags)
 508 {
 509         u32 attributes;
 510         int mrec_flags;
 511         u32 sd_size = 0;
 512         int ret;
 513         char dos_name_utf8[64];
 514         struct dentry *root;
 515
 516         mrec_flags = ni->mrec->flags;
 517         struct SECURITY_CONTEXT ctx;
 518         memset(&ctx, 0, sizeof(ctx));
 519         ctx.vol = ni->vol;
 520         ret = ntfs_xattr_system_getxattr(&ctx, XATTR_NTFS_ATTRIB,
 521                                          ni, dir_ni, (char *)&attributes,
 522                                          sizeof(u32));
 523         if (ret != 4) {
 524                 ERROR_WITH_ERRNO("Failed to get NTFS attributes from `%s'",
 525                                  path);
 526                 return WIMLIB_ERR_NTFS_3G;
 527         }
 528
 529         if (exclude_path(path, config, false)) {
 530                 if (flags & WIMLIB_ADD_IMAGE_FLAG_VERBOSE) {
 531                         const char *file_type;
 532                         if (attributes & MFT_RECORD_IS_DIRECTORY)
 533                                 file_type = "directory";
 534                         else
 535                                 file_type = "file";
 536                         printf("Excluding %s `%s' from capture\n",
 537                                file_type, path);
 538                 }
 539                 *root_p = NULL;
 540                 return 0;
 541         }
 542
 543         if (flags & WIMLIB_ADD_IMAGE_FLAG_VERBOSE)
 544                 printf("Scanning `%s'\n", path);
 545
 546         root = new_dentry_with_timeless_inode(path_basename(path));
 547         if (!root)
 548                 return WIMLIB_ERR_NOMEM;
 549         *root_p = root;
 550
 551         if (dir_ni && (name_type == FILE_NAME_WIN32_AND_DOS
 552                        || name_type == FILE_NAME_WIN32))
 553         {
 554                 ret = ntfs_get_ntfs_dos_name(ni, dir_ni, dos_name_utf8,
 555                                              sizeof(dos_name_utf8));
 556                 if (ret > 0) {
 557                         DEBUG("Changing short name of `%s'", path);
 558                         ret = change_dentry_short_name(root, dos_name_utf8,
 559                                                        ret);
 560                         if (ret != 0)
 561                                 return ret;
 562                 } else {
 563                 #ifdef ENODATA
 564                         if (errno != ENODATA) {
 565                                 ERROR_WITH_ERRNO("Error getting DOS name "
 566                                                  "of `%s'", path);
 567                                 return WIMLIB_ERR_NTFS_3G;
 568                         }
 569                 #endif
 570                 }
 571         }
 572
 573         root->d_inode->creation_time    = le64_to_cpu(ni->creation_time);
 574         root->d_inode->last_write_time  = le64_to_cpu(ni->last_data_change_time);
 575         root->d_inode->last_access_time = le64_to_cpu(ni->last_access_time);
 576         root->d_inode->attributes       = le32_to_cpu(attributes);
 577         root->d_inode->ino              = ni->mft_no;
 578         root->d_inode->resolved         = true;
 579
 580         if (attributes & FILE_ATTR_REPARSE_POINT) {
 581                 /* Junction point, symbolic link, or other reparse point */
 582                 ret = capture_ntfs_streams(root, ni, path, path_len,
 583                                            lookup_table, ntfs_vol_p,
 584                                            AT_REPARSE_POINT);
 585         } else if (mrec_flags & MFT_RECORD_IS_DIRECTORY) {
 586
 587                 /* Normal directory */
 588                 s64 pos = 0;
 589                 struct readdir_ctx ctx = {
 590                         .parent       = root,
 591                         .dir_ni       = ni,
 592                         .path         = path,
 593                         .path_len     = path_len,
 594                         .lookup_table = lookup_table,
 595                         .sd_set       = sd_set,
 596                         .config       = config,
 597                         .ntfs_vol_p   = ntfs_vol_p,
 598                         .flags        = flags,
 599                 };
 600                 ret = ntfs_readdir(ni, &pos, &ctx, wim_ntfs_capture_filldir);
 601                 if (ret != 0) {
 602                         ERROR_WITH_ERRNO("ntfs_readdir()");
 603                         ret = WIMLIB_ERR_NTFS_3G;
 604                 }
 605         } else {
 606                 /* Normal file */
 607                 ret = capture_ntfs_streams(root, ni, path, path_len,
 608                                            lookup_table, ntfs_vol_p,
 609                                            AT_DATA);
 610         }
 611         if (ret != 0)
 612                 return ret;
 613
 614         char _sd[1];
 615         char *sd = _sd;
 616         errno = 0;
 617         ret = ntfs_xattr_system_getxattr(&ctx, XATTR_NTFS_ACL,
 618                                          ni, dir_ni, sd,
 619                                          sizeof(sd));
 620         if (ret > sizeof(sd)) {
 621                 sd = alloca(ret);
 622                 ret = ntfs_xattr_system_getxattr(&ctx, XATTR_NTFS_ACL,
 623                                                  ni, dir_ni, sd, ret);
 624         }
 625         if (ret > 0) {
 626                 root->d_inode->security_id = sd_set_add_sd(sd_set, sd, ret);
 627                 if (root->d_inode->security_id == -1) {
 628                         ERROR("Out of memory");
 629                         return WIMLIB_ERR_NOMEM;
 630                 }
 631                 DEBUG("Added security ID = %u for `%s'",
 632                       root->d_inode->security_id, path);
 633                 ret = 0;
 634         } else if (ret < 0) {
 635                 ERROR_WITH_ERRNO("Failed to get security information from "
 636                                  "`%s'", path);
 637                 ret = WIMLIB_ERR_NTFS_3G;
 638         } else {
 639                 root->d_inode->security_id = -1;
 640                 DEBUG("No security ID for `%s'", path);
 641         }
 642         return ret;
 643 }
 644
 645 static int build_dentry_tree_ntfs(struct dentry **root_p,
 646                                   const char *device,
 647                                   struct lookup_table *lookup_table,
 648                                   struct wim_security_data *sd,
 649                                   const struct capture_config *config,
 650                                   int flags,
 651                                   void *extra_arg)
 652 {
 653         ntfs_volume *vol;
 654         ntfs_inode *root_ni;
 655         int ret = 0;
 656         struct sd_set sd_set = {
 657                 .sd = sd,
 658                 .root = NULL,
 659         };
 660         ntfs_volume **ntfs_vol_p = extra_arg;
 661
 662         DEBUG("Mounting NTFS volume `%s' read-only", device);
 663
 664         vol = ntfs_mount(device, MS_RDONLY);
 665         if (!vol) {
 666                 ERROR_WITH_ERRNO("Failed to mount NTFS volume `%s' read-only",
 667                                  device);
 668                 return WIMLIB_ERR_NTFS_3G;
 669         }
 670         ntfs_open_secure(vol);
 671
 672         /* We don't want to capture the special NTFS files such as $Bitmap.  Not
 673          * to be confused with "hidden" or "system" files which are real files
 674          * that we do need to capture.  */
 675         NVolClearShowSysFiles(vol);
 676
 677         DEBUG("Opening root NTFS dentry");
 678         root_ni = ntfs_inode_open(vol, FILE_root);
 679         if (!root_ni) {
 680                 ERROR_WITH_ERRNO("Failed to open root inode of NTFS volume "
 681                                  "`%s'", device);
 682                 ret = WIMLIB_ERR_NTFS_3G;
 683                 goto out;
 684         }
 685
 686         /* Currently we assume that all the UTF-8 paths fit into this length and
 687          * there is no check for overflow. */
 688         char *path = MALLOC(32768);
 689         if (!path) {
 690                 ERROR("Could not allocate memory for NTFS pathname");
 691                 goto out_cleanup;
 692         }
 693
 694         path[0] = '/';
 695         path[1] = '\0';
 696         ret = build_dentry_tree_ntfs_recursive(root_p, NULL, root_ni, path, 1,
 697                                                FILE_NAME_POSIX, lookup_table,
 698                                                &sd_set, config, ntfs_vol_p,
 699                                                flags);
 700 out_cleanup:
 701         FREE(path);
 702         ntfs_inode_close(root_ni);
 703         destroy_sd_set(&sd_set);
 704
 705 out:
 706         if (ret) {
 707                 if (ntfs_umount(vol, FALSE) != 0) {
 708                         ERROR_WITH_ERRNO("Failed to unmount NTFS volume `%s'",
 709                                          device);
 710                         if (ret == 0)
 711                                 ret = WIMLIB_ERR_NTFS_3G;
 712                 }
 713         } else {
 714                 /* We need to leave the NTFS volume mounted so that we can read
 715                  * the NTFS files again when we are actually writing the WIM */
 716                 *ntfs_vol_p = vol;
 717         }
 718         return ret;
 719 }
 720
 721
 722
 723 WIMLIBAPI int wimlib_add_image_from_ntfs_volume(WIMStruct *w,
 724                                                 const char *device,
 725                                                 const char *name,
 726                                                 const char *config_str,
 727                                                 size_t config_len,
 728                                                 int flags)
 729 {
 730         if (flags & (WIMLIB_ADD_IMAGE_FLAG_DEREFERENCE)) {
 731                 ERROR("Cannot dereference files when capturing directly from NTFS");
 732                 return WIMLIB_ERR_INVALID_PARAM;
 733         }
 734         return do_add_image(w, device, name, config_str, config_len, flags,
 735                             build_dentry_tree_ntfs, &w->ntfs_vol);
 736 }
 737
 738 #else /* WITH_NTFS_3G */
 739 WIMLIBAPI int wimlib_add_image_from_ntfs_volume(WIMStruct *w,
 740                                                 const char *device,
 741                                                 const char *name,
 742                                                 const char *config_str,
 743                                                 size_t config_len,
 744                                                 int flags)
 745 {
 746         ERROR("wimlib was compiled without support for NTFS-3g, so");
 747         ERROR("we cannot capture a WIM image directly from a NTFS volume");
 748         return WIMLIB_ERR_UNSUPPORTED;
 749 }
 750 #endif /* WITH_NTFS_3G */