wimlib.net Git - wimlib/blob - src/win32_capture.c

   1 /*
   2  * win32_capture.c - Windows-specific code for capturing files into a WIM image.
   3  *
   4  * This now uses the native Windows NT API a lot and not just Win32.
   5  */
   6
   7 /*
   8  * Copyright (C) 2013, 2014, 2015 Eric Biggers
   9  *
  10  * This file is free software; you can redistribute it and/or modify it under
  11  * the terms of the GNU Lesser General Public License as published by the Free
  12  * Software Foundation; either version 3 of the License, or (at your option) any
  13  * later version.
  14  *
  15  * This file is distributed in the hope that it will be useful, but WITHOUT
  16  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  17  * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
  18  * details.
  19  *
  20  * You should have received a copy of the GNU Lesser General Public License
  21  * along with this file; if not, see http://www.gnu.org/licenses/.
  22  */
  23
  24 #ifdef __WIN32__
  25
  26 #ifdef HAVE_CONFIG_H
  27 #  include "config.h"
  28 #endif
  29
  30 #include "wimlib/win32_common.h"
  31
  32 #include "wimlib/assert.h"
  33 #include "wimlib/blob_table.h"
  34 #include "wimlib/capture.h"
  35 #include "wimlib/dentry.h"
  36 #include "wimlib/encoding.h"
  37 #include "wimlib/endianness.h"
  38 #include "wimlib/error.h"
  39 #include "wimlib/paths.h"
  40 #include "wimlib/reparse.h"
  41 #include "wimlib/win32_vss.h"
  42 #include "wimlib/wof.h"
  43
  44 struct winnt_scan_ctx {
  45         u32 vol_flags;
  46         unsigned long num_get_sd_access_denied;
  47         unsigned long num_get_sacl_priv_notheld;
  48
  49         /* True if WOF is definitely not attached to the volume being scanned;
  50          * false if it may be  */
  51         bool wof_not_attached;
  52
  53         /* A reference to the VSS snapshot being used, or NULL if none  */
  54         struct vss_snapshot *snapshot;
  55 };
  56
  57 static inline const wchar_t *
  58 printable_path(const wchar_t *full_path)
  59 {
  60         /* Skip over \\?\ or \??\  */
  61         return full_path + 4;
  62 }
  63
  64 /* Description of where data is located on a Windows filesystem  */
  65 struct windows_file {
  66
  67         /* Is the data the raw encrypted data of an EFS-encrypted file?  */
  68         u64 is_encrypted : 1;
  69
  70         /* The file's LCN (logical cluster number) for sorting, or 0 if unknown.
  71          */
  72         u64 sort_key : 63;
  73
  74         /* A reference to the VSS snapshot containing the file, or NULL if none.
  75          */
  76         struct vss_snapshot *snapshot;
  77
  78         /* The path to the file.  If 'is_encrypted=0' this is an NT namespace
  79          * path; if 'is_encrypted=1' this is a Win32 namespace path.  */
  80         wchar_t path[];
  81 };
  82
  83 /* Allocate a 'struct windows_file' to describe the location of a data stream.
  84  */
  85 static struct windows_file *
  86 alloc_windows_file(bool is_encrypted, struct vss_snapshot *snapshot,
  87                    const wchar_t *path, size_t path_nchars,
  88                    const wchar_t *stream_name, size_t stream_name_nchars)
  89 {
  90         struct windows_file *file;
  91         wchar_t *p;
  92
  93         file = MALLOC(sizeof(struct windows_file) +
  94                       (path_nchars + (stream_name_nchars ? 1 : 0) +
  95                        stream_name_nchars + 1) * sizeof(wchar_t));
  96         if (!file)
  97                 return NULL;
  98
  99         file->is_encrypted = is_encrypted;
 100         file->sort_key = 0;
 101         file->snapshot = vss_get_snapshot(snapshot);
 102         p = wmempcpy(file->path, path, path_nchars);
 103         if (stream_name_nchars) {
 104                 /* Named data stream  */
 105                 *p++ = L':';
 106                 p = wmempcpy(p, stream_name, stream_name_nchars);
 107         }
 108         *p = L'\0';
 109         return file;
 110 }
 111
 112 /* Add a stream, located on a Windows filesystem, to the specified WIM inode.
 113  */
 114 static int
 115 add_stream(struct wim_inode *inode, bool is_encrypted,
 116            struct vss_snapshot *snapshot, u64 size,
 117            const wchar_t *path, size_t path_nchars,
 118            int stream_type, const utf16lechar *stream_name, size_t stream_name_nchars,
 119            struct list_head *unhashed_blobs)
 120 {
 121         struct blob_descriptor *blob = NULL;
 122         struct wim_inode_stream *strm;
 123
 124         /* If the stream is nonempty, create a blob descriptor for it.  */
 125         if (size) {
 126                 blob = new_blob_descriptor();
 127                 if (!blob)
 128                         goto err_nomem;
 129
 130                 blob->windows_file = alloc_windows_file(is_encrypted, snapshot,
 131                                                         path, path_nchars,
 132                                                         stream_name,
 133                                                         stream_name_nchars);
 134                 if (!blob->windows_file)
 135                         goto err_nomem;
 136
 137                 blob->blob_location = BLOB_IN_WINDOWS_FILE;
 138                 blob->file_inode = inode;
 139                 blob->size = size;
 140         }
 141
 142         strm = inode_add_stream(inode, stream_type, stream_name, blob);
 143         if (!strm)
 144                 goto err_nomem;
 145
 146         prepare_unhashed_blob(blob, inode, strm->stream_id, unhashed_blobs);
 147         return 0;
 148
 149 err_nomem:
 150         free_blob_descriptor(blob);
 151         return WIMLIB_ERR_NOMEM;
 152 }
 153
 154 struct windows_file *
 155 clone_windows_file(const struct windows_file *file)
 156 {
 157         struct windows_file *new;
 158
 159         new = memdup(file, sizeof(struct windows_file) +
 160                            (wcslen(file->path) + 1) * sizeof(wchar_t));
 161         if (new)
 162                 vss_get_snapshot(new->snapshot);
 163         return new;
 164 }
 165
 166 void
 167 free_windows_file(struct windows_file *file)
 168 {
 169         vss_put_snapshot(file->snapshot);
 170         FREE(file);
 171 }
 172
 173 int
 174 cmp_windows_files(const struct windows_file *file1,
 175                   const struct windows_file *file2)
 176 {
 177         /* Compare by starting LCN (logical cluster number)  */
 178         int v = cmp_u64(file1->sort_key, file2->sort_key);
 179         if (v)
 180                 return v;
 181
 182         /* Compare files by path: just a heuristic that will place files
 183          * in the same directory next to each other.  */
 184         return wcscmp(file1->path, file2->path);
 185 }
 186
 187 const wchar_t *
 188 get_windows_file_path(const struct windows_file *file)
 189 {
 190         return file->path;
 191 }
 192
 193 /*
 194  * If cur_dir is not NULL, open an existing file relative to the already-open
 195  * directory cur_dir.
 196  *
 197  * Otherwise, open the file specified by @path, which must be a Windows NT
 198  * namespace path.
 199  */
 200 static NTSTATUS
 201 winnt_openat(HANDLE cur_dir, const wchar_t *path, size_t path_nchars,
 202              ACCESS_MASK perms, HANDLE *h_ret)
 203 {
 204         UNICODE_STRING name;
 205         OBJECT_ATTRIBUTES attr;
 206         IO_STATUS_BLOCK iosb;
 207         NTSTATUS status;
 208
 209         name.Length = path_nchars * sizeof(wchar_t);
 210         name.MaximumLength = name.Length + sizeof(wchar_t);
 211         name.Buffer = (wchar_t *)path;
 212
 213         attr.Length = sizeof(attr);
 214         attr.RootDirectory = cur_dir;
 215         attr.ObjectName = &name;
 216         attr.Attributes = 0;
 217         attr.SecurityDescriptor = NULL;
 218         attr.SecurityQualityOfService = NULL;
 219
 220 retry:
 221         status = (*func_NtOpenFile)(h_ret, perms, &attr, &iosb,
 222                                     FILE_SHARE_VALID_FLAGS,
 223                                     FILE_OPEN_REPARSE_POINT |
 224                                             FILE_OPEN_FOR_BACKUP_INTENT |
 225                                             FILE_SYNCHRONOUS_IO_NONALERT |
 226                                             FILE_SEQUENTIAL_ONLY);
 227         if (!NT_SUCCESS(status)) {
 228                 /* Try requesting fewer permissions  */
 229                 if (status == STATUS_ACCESS_DENIED ||
 230                     status == STATUS_PRIVILEGE_NOT_HELD) {
 231                         if (perms & ACCESS_SYSTEM_SECURITY) {
 232                                 perms &= ~ACCESS_SYSTEM_SECURITY;
 233                                 goto retry;
 234                         }
 235                         if (perms & READ_CONTROL) {
 236                                 perms &= ~READ_CONTROL;
 237                                 goto retry;
 238                         }
 239                 }
 240         }
 241         return status;
 242 }
 243
 244 static int
 245 read_winnt_stream_prefix(const wchar_t *path, u64 size,
 246                          const struct read_blob_callbacks *cbs)
 247 {
 248         HANDLE h;
 249         NTSTATUS status;
 250         u8 buf[BUFFER_SIZE];
 251         u64 bytes_remaining;
 252         int ret;
 253
 254         status = winnt_openat(NULL, path, wcslen(path),
 255                               FILE_READ_DATA | SYNCHRONIZE, &h);
 256         if (!NT_SUCCESS(status)) {
 257                 winnt_error(status, L"\"%ls\": Can't open for reading",
 258                             printable_path(path));
 259                 return WIMLIB_ERR_OPEN;
 260         }
 261
 262         ret = 0;
 263         bytes_remaining = size;
 264         while (bytes_remaining) {
 265                 IO_STATUS_BLOCK iosb;
 266                 ULONG count;
 267                 ULONG bytes_read;
 268
 269                 count = min(sizeof(buf), bytes_remaining);
 270
 271                 status = (*func_NtReadFile)(h, NULL, NULL, NULL,
 272                                             &iosb, buf, count, NULL, NULL);
 273                 if (unlikely(!NT_SUCCESS(status))) {
 274                         if (status == STATUS_END_OF_FILE) {
 275                                 ERROR("\"%ls\": File was concurrently truncated",
 276                                       printable_path(path));
 277                                 ret = WIMLIB_ERR_CONCURRENT_MODIFICATION_DETECTED;
 278                         } else {
 279                                 winnt_error(status, L"\"%ls\": Error reading data",
 280                                             printable_path(path));
 281                                 ret = WIMLIB_ERR_READ;
 282                         }
 283                         break;
 284                 }
 285
 286                 bytes_read = iosb.Information;
 287
 288                 bytes_remaining -= bytes_read;
 289                 ret = call_consume_chunk(buf, bytes_read, cbs);
 290                 if (ret)
 291                         break;
 292         }
 293         (*func_NtClose)(h);
 294         return ret;
 295 }
 296
 297 struct win32_encrypted_read_ctx {
 298         const struct read_blob_callbacks *cbs;
 299         int wimlib_err_code;
 300         u64 bytes_remaining;
 301 };
 302
 303 static DWORD WINAPI
 304 win32_encrypted_export_cb(unsigned char *data, void *_ctx, unsigned long len)
 305 {
 306         struct win32_encrypted_read_ctx *ctx = _ctx;
 307         int ret;
 308         size_t bytes_to_consume = min(len, ctx->bytes_remaining);
 309
 310         if (bytes_to_consume == 0)
 311                 return ERROR_SUCCESS;
 312
 313         ret = call_consume_chunk(data, bytes_to_consume, ctx->cbs);
 314         if (ret) {
 315                 ctx->wimlib_err_code = ret;
 316                 /* It doesn't matter what error code is returned here, as long
 317                  * as it isn't ERROR_SUCCESS.  */
 318                 return ERROR_READ_FAULT;
 319         }
 320         ctx->bytes_remaining -= bytes_to_consume;
 321         return ERROR_SUCCESS;
 322 }
 323
 324 static int
 325 read_win32_encrypted_file_prefix(const wchar_t *path, bool is_dir, u64 size,
 326                                  const struct read_blob_callbacks *cbs)
 327 {
 328         struct win32_encrypted_read_ctx export_ctx;
 329         DWORD err;
 330         void *file_ctx;
 331         int ret;
 332         DWORD flags = 0;
 333
 334         if (is_dir)
 335                 flags |= CREATE_FOR_DIR;
 336
 337         export_ctx.cbs = cbs;
 338         export_ctx.wimlib_err_code = 0;
 339         export_ctx.bytes_remaining = size;
 340
 341         err = OpenEncryptedFileRaw(path, flags, &file_ctx);
 342         if (err != ERROR_SUCCESS) {
 343                 win32_error(err,
 344                             L"Failed to open encrypted file \"%ls\" for raw read",
 345                             printable_path(path));
 346                 return WIMLIB_ERR_OPEN;
 347         }
 348         err = ReadEncryptedFileRaw(win32_encrypted_export_cb,
 349                                    &export_ctx, file_ctx);
 350         if (err != ERROR_SUCCESS) {
 351                 ret = export_ctx.wimlib_err_code;
 352                 if (ret == 0) {
 353                         win32_error(err,
 354                                     L"Failed to read encrypted file \"%ls\"",
 355                                     printable_path(path));
 356                         ret = WIMLIB_ERR_READ;
 357                 }
 358         } else if (export_ctx.bytes_remaining != 0) {
 359                 ERROR("Only could read %"PRIu64" of %"PRIu64" bytes from "
 360                       "encrypted file \"%ls\"",
 361                       size - export_ctx.bytes_remaining, size,
 362                       printable_path(path));
 363                 ret = WIMLIB_ERR_READ;
 364         } else {
 365                 ret = 0;
 366         }
 367         CloseEncryptedFileRaw(file_ctx);
 368         return ret;
 369 }
 370
 371 /* Read the first @size bytes from the file, or named data stream of a file,
 372  * described by @blob.  */
 373 int
 374 read_windows_file_prefix(const struct blob_descriptor *blob, u64 size,
 375                          const struct read_blob_callbacks *cbs)
 376 {
 377         const struct windows_file *file = blob->windows_file;
 378
 379         if (unlikely(file->is_encrypted)) {
 380                 bool is_dir = (blob->file_inode->i_attributes & FILE_ATTRIBUTE_DIRECTORY);
 381                 return read_win32_encrypted_file_prefix(file->path, is_dir, size, cbs);
 382         }
 383
 384         return read_winnt_stream_prefix(file->path, size, cbs);
 385 }
 386
 387 /*
 388  * Load the short name of a file into a WIM dentry.
 389  */
 390 static noinline_for_stack NTSTATUS
 391 winnt_get_short_name(HANDLE h, struct wim_dentry *dentry)
 392 {
 393         /* It's not any harder to just make the NtQueryInformationFile() system
 394          * call ourselves, and it saves a dumb call to FindFirstFile() which of
 395          * course has to create its own handle.  */
 396         NTSTATUS status;
 397         IO_STATUS_BLOCK iosb;
 398         u8 buf[128] _aligned_attribute(8);
 399         const FILE_NAME_INFORMATION *info;
 400
 401         status = (*func_NtQueryInformationFile)(h, &iosb, buf, sizeof(buf),
 402                                                 FileAlternateNameInformation);
 403         info = (const FILE_NAME_INFORMATION *)buf;
 404         if (NT_SUCCESS(status) && info->FileNameLength != 0) {
 405                 dentry->d_short_name = utf16le_dupz(info->FileName,
 406                                                     info->FileNameLength);
 407                 if (!dentry->d_short_name)
 408                         return STATUS_NO_MEMORY;
 409                 dentry->d_short_name_nbytes = info->FileNameLength;
 410         }
 411         return status;
 412 }
 413
 414 /*
 415  * Load the security descriptor of a file into the corresponding inode and the
 416  * WIM image's security descriptor set.
 417  */
 418 static noinline_for_stack NTSTATUS
 419 winnt_get_security_descriptor(HANDLE h, struct wim_inode *inode,
 420                               struct wim_sd_set *sd_set,
 421                               struct winnt_scan_ctx *ctx, int add_flags)
 422 {
 423         SECURITY_INFORMATION requestedInformation;
 424         u8 _buf[4096] _aligned_attribute(8);
 425         u8 *buf;
 426         ULONG bufsize;
 427         ULONG len_needed;
 428         NTSTATUS status;
 429
 430         /*
 431          * LABEL_SECURITY_INFORMATION is needed on Windows Vista and 7 because
 432          * Microsoft decided to add mandatory integrity labels to the SACL but
 433          * not have them returned by SACL_SECURITY_INFORMATION.
 434          *
 435          * BACKUP_SECURITY_INFORMATION is needed on Windows 8 because Microsoft
 436          * decided to add even more stuff to the SACL and still not have it
 437          * returned by SACL_SECURITY_INFORMATION; but they did remember that
 438          * backup applications exist and simply want to read the stupid thing
 439          * once and for all, so they added a flag to read the entire security
 440          * descriptor.
 441          *
 442          * Older versions of Windows tolerate these new flags being passed in.
 443          */
 444         requestedInformation = OWNER_SECURITY_INFORMATION |
 445                                GROUP_SECURITY_INFORMATION |
 446                                DACL_SECURITY_INFORMATION |
 447                                SACL_SECURITY_INFORMATION |
 448                                LABEL_SECURITY_INFORMATION |
 449                                BACKUP_SECURITY_INFORMATION;
 450
 451         buf = _buf;
 452         bufsize = sizeof(_buf);
 453
 454         /*
 455          * We need the file's security descriptor in
 456          * SECURITY_DESCRIPTOR_RELATIVE format, and we currently have a handle
 457          * opened with as many relevant permissions as possible.  At this point,
 458          * on Windows there are a number of options for reading a file's
 459          * security descriptor:
 460          *
 461          * GetFileSecurity():  This takes in a path and returns the
 462          * SECURITY_DESCRIPTOR_RELATIVE.  Problem: this uses an internal handle,
 463          * not ours, and the handle created internally doesn't specify
 464          * FILE_FLAG_BACKUP_SEMANTICS.  Therefore there can be access denied
 465          * errors on some files and directories, even when running as the
 466          * Administrator.
 467          *
 468          * GetSecurityInfo():  This takes in a handle and returns the security
 469          * descriptor split into a bunch of different parts.  This should work,
 470          * but it's dumb because we have to put the security descriptor back
 471          * together again.
 472          *
 473          * BackupRead():  This can read the security descriptor, but this is a
 474          * difficult-to-use API, probably only works as the Administrator, and
 475          * the format of the returned data is not well documented.
 476          *
 477          * NtQuerySecurityObject():  This is exactly what we need, as it takes
 478          * in a handle and returns the security descriptor in
 479          * SECURITY_DESCRIPTOR_RELATIVE format.  Only problem is that it's a
 480          * ntdll function and therefore not officially part of the Win32 API.
 481          * Oh well.
 482          */
 483         while (!(NT_SUCCESS(status = (*func_NtQuerySecurityObject)(h,
 484                                                                    requestedInformation,
 485                                                                    (PSECURITY_DESCRIPTOR)buf,
 486                                                                    bufsize,
 487                                                                    &len_needed))))
 488         {
 489                 switch (status) {
 490                 case STATUS_BUFFER_TOO_SMALL:
 491                         wimlib_assert(buf == _buf);
 492                         buf = MALLOC(len_needed);
 493                         if (!buf)
 494                                 return STATUS_NO_MEMORY;
 495                         bufsize = len_needed;
 496                         break;
 497                 case STATUS_PRIVILEGE_NOT_HELD:
 498                 case STATUS_ACCESS_DENIED:
 499                         if (add_flags & WIMLIB_ADD_FLAG_STRICT_ACLS) {
 500                 default:
 501                                 /* Permission denied in STRICT_ACLS mode, or
 502                                  * unknown error.  */
 503                                 goto out_free_buf;
 504                         }
 505                         if (requestedInformation & SACL_SECURITY_INFORMATION) {
 506                                 /* Try again without the SACL.  */
 507                                 ctx->num_get_sacl_priv_notheld++;
 508                                 requestedInformation &= ~(SACL_SECURITY_INFORMATION |
 509                                                           LABEL_SECURITY_INFORMATION |
 510                                                           BACKUP_SECURITY_INFORMATION);
 511                                 break;
 512                         }
 513                         /* Fake success (useful when capturing as
 514                          * non-Administrator).  */
 515                         ctx->num_get_sd_access_denied++;
 516                         status = STATUS_SUCCESS;
 517                         goto out_free_buf;
 518                 }
 519         }
 520
 521         /* Add the security descriptor to the WIM image, and save its ID in
 522          * file's inode.  */
 523         inode->i_security_id = sd_set_add_sd(sd_set, buf, len_needed);
 524         if (unlikely(inode->i_security_id < 0))
 525                 status = STATUS_NO_MEMORY;
 526 out_free_buf:
 527         if (unlikely(buf != _buf))
 528                 FREE(buf);
 529         return status;
 530 }
 531
 532 static int
 533 winnt_build_dentry_tree_recursive(struct wim_dentry **root_ret,
 534                                   HANDLE cur_dir,
 535                                   wchar_t *full_path,
 536                                   size_t full_path_nchars,
 537                                   const wchar_t *filename,
 538                                   size_t filename_nchars,
 539                                   struct capture_params *params,
 540                                   struct winnt_scan_ctx *ctx);
 541
 542 static int
 543 winnt_recurse_directory(HANDLE h,
 544                         wchar_t *full_path,
 545                         size_t full_path_nchars,
 546                         struct wim_dentry *parent,
 547                         struct capture_params *params,
 548                         struct winnt_scan_ctx *ctx)
 549 {
 550         void *buf;
 551         const size_t bufsize = 8192;
 552         IO_STATUS_BLOCK iosb;
 553         NTSTATUS status;
 554         int ret;
 555
 556         buf = MALLOC(bufsize);
 557         if (!buf)
 558                 return WIMLIB_ERR_NOMEM;
 559
 560         /* Using NtQueryDirectoryFile() we can re-use the same open handle,
 561          * which we opened with FILE_FLAG_BACKUP_SEMANTICS.  */
 562
 563         while (NT_SUCCESS(status = (*func_NtQueryDirectoryFile)(h, NULL, NULL, NULL,
 564                                                                 &iosb, buf, bufsize,
 565                                                                 FileNamesInformation,
 566                                                                 FALSE, NULL, FALSE)))
 567         {
 568                 const FILE_NAMES_INFORMATION *info = buf;
 569                 for (;;) {
 570                         if (!should_ignore_filename(info->FileName,
 571                                                     info->FileNameLength / 2))
 572                         {
 573                                 wchar_t *p;
 574                                 wchar_t *filename;
 575                                 struct wim_dentry *child;
 576
 577                                 p = full_path + full_path_nchars;
 578                                 /* Only add a backslash if we don't already have
 579                                  * one.  This prevents a duplicate backslash
 580                                  * from being added when the path to the capture
 581                                  * dir had a trailing backslash.  */
 582                                 if (*(p - 1) != L'\\')
 583                                         *p++ = L'\\';
 584                                 filename = p;
 585                                 p = wmempcpy(filename, info->FileName,
 586                                              info->FileNameLength / 2);
 587                                 *p = '\0';
 588
 589                                 ret = winnt_build_dentry_tree_recursive(
 590                                                         &child,
 591                                                         h,
 592                                                         full_path,
 593                                                         p - full_path,
 594                                                         filename,
 595                                                         info->FileNameLength / 2,
 596                                                         params,
 597                                                         ctx);
 598
 599                                 full_path[full_path_nchars] = L'\0';
 600
 601                                 if (ret)
 602                                         goto out_free_buf;
 603                                 attach_scanned_tree(parent, child, params->blob_table);
 604                         }
 605                         if (info->NextEntryOffset == 0)
 606                                 break;
 607                         info = (const FILE_NAMES_INFORMATION *)
 608                                         ((const u8 *)info + info->NextEntryOffset);
 609                 }
 610         }
 611
 612         if (unlikely(status != STATUS_NO_MORE_FILES)) {
 613                 winnt_error(status, L"\"%ls\": Can't read directory",
 614                             printable_path(full_path));
 615                 ret = WIMLIB_ERR_READ;
 616         }
 617 out_free_buf:
 618         FREE(buf);
 619         return ret;
 620 }
 621
 622 /* Reparse point fixup status code  */
 623 #define RP_FIXED        (-1)
 624
 625 static bool
 626 file_has_ino_and_dev(HANDLE h, u64 ino, u64 dev)
 627 {
 628         NTSTATUS status;
 629         IO_STATUS_BLOCK iosb;
 630         FILE_INTERNAL_INFORMATION int_info;
 631         FILE_FS_VOLUME_INFORMATION vol_info;
 632
 633         status = (*func_NtQueryInformationFile)(h, &iosb,
 634                                                 &int_info, sizeof(int_info),
 635                                                 FileInternalInformation);
 636         if (!NT_SUCCESS(status))
 637                 return false;
 638
 639         if (int_info.IndexNumber.QuadPart != ino)
 640                 return false;
 641
 642         status = (*func_NtQueryVolumeInformationFile)(h, &iosb,
 643                                                       &vol_info, sizeof(vol_info),
 644                                                       FileFsVolumeInformation);
 645         if (!(NT_SUCCESS(status) || status == STATUS_BUFFER_OVERFLOW))
 646                 return false;
 647
 648         if (iosb.Information <
 649              offsetof(FILE_FS_VOLUME_INFORMATION, VolumeSerialNumber) +
 650              sizeof(vol_info.VolumeSerialNumber))
 651                 return false;
 652
 653         return (vol_info.VolumeSerialNumber == dev);
 654 }
 655
 656 /*
 657  * This is the Windows equivalent of unix_relativize_link_target(); see there
 658  * for general details.  This version works with an "absolute" Windows link
 659  * target, specified from the root of the Windows kernel object namespace.  Note
 660  * that we have to open directories with a trailing slash when present because
 661  * \??\E: opens the E: device itself and not the filesystem root directory.
 662  */
 663 static const wchar_t *
 664 winnt_relativize_link_target(const wchar_t *target, size_t target_nbytes,
 665                              u64 ino, u64 dev)
 666 {
 667         UNICODE_STRING name;
 668         OBJECT_ATTRIBUTES attr;
 669         IO_STATUS_BLOCK iosb;
 670         NTSTATUS status;
 671         const wchar_t *target_end;
 672         const wchar_t *p;
 673
 674         target_end = target + (target_nbytes / sizeof(wchar_t));
 675
 676         /* Empty path??? */
 677         if (target_end == target)
 678                 return target;
 679
 680         /* No leading slash???  */
 681         if (target[0] != L'\\')
 682                 return target;
 683
 684         /* UNC path???  */
 685         if ((target_end - target) >= 2 &&
 686             target[0] == L'\\' && target[1] == L'\\')
 687                 return target;
 688
 689         attr.Length = sizeof(attr);
 690         attr.RootDirectory = NULL;
 691         attr.ObjectName = &name;
 692         attr.Attributes = 0;
 693         attr.SecurityDescriptor = NULL;
 694         attr.SecurityQualityOfService = NULL;
 695
 696         name.Buffer = (wchar_t *)target;
 697         name.Length = 0;
 698         p = target;
 699         do {
 700                 HANDLE h;
 701                 const wchar_t *orig_p = p;
 702
 703                 /* Skip non-backslashes  */
 704                 while (p != target_end && *p != L'\\')
 705                         p++;
 706
 707                 /* Skip backslashes  */
 708                 while (p != target_end && *p == L'\\')
 709                         p++;
 710
 711                 /* Append path component  */
 712                 name.Length += (p - orig_p) * sizeof(wchar_t);
 713                 name.MaximumLength = name.Length;
 714
 715                 /* Try opening the file  */
 716                 status = (*func_NtOpenFile) (&h,
 717                                              FILE_READ_ATTRIBUTES | FILE_TRAVERSE,
 718                                              &attr,
 719                                              &iosb,
 720                                              FILE_SHARE_VALID_FLAGS,
 721                                              FILE_OPEN_FOR_BACKUP_INTENT);
 722
 723                 if (NT_SUCCESS(status)) {
 724                         /* Reset root directory  */
 725                         if (attr.RootDirectory)
 726                                 (*func_NtClose)(attr.RootDirectory);
 727                         attr.RootDirectory = h;
 728                         name.Buffer = (wchar_t *)p;
 729                         name.Length = 0;
 730
 731                         if (file_has_ino_and_dev(h, ino, dev))
 732                                 goto out_close_root_dir;
 733                 }
 734         } while (p != target_end);
 735
 736         p = target;
 737
 738 out_close_root_dir:
 739         if (attr.RootDirectory)
 740                 (*func_NtClose)(attr.RootDirectory);
 741         while (p > target && *(p - 1) == L'\\')
 742                 p--;
 743         return p;
 744 }
 745
 746 static int
 747 winnt_rpfix_progress(struct capture_params *params, const wchar_t *path,
 748                      const struct link_reparse_point *link, int scan_status)
 749 {
 750         size_t print_name_nchars = link->print_name_nbytes / sizeof(wchar_t);
 751         wchar_t print_name0[print_name_nchars + 1];
 752
 753         wmemcpy(print_name0, link->print_name, print_name_nchars);
 754         print_name0[print_name_nchars] = L'\0';
 755
 756         params->progress.scan.cur_path = printable_path(path);
 757         params->progress.scan.symlink_target = print_name0;
 758         return do_capture_progress(params, scan_status, NULL);
 759 }
 760
 761 static int
 762 winnt_try_rpfix(struct reparse_buffer_disk *rpbuf, u16 *rpbuflen_p,
 763                 const wchar_t *path, struct capture_params *params)
 764 {
 765         struct link_reparse_point link;
 766         const wchar_t *rel_target;
 767         int ret;
 768
 769         if (parse_link_reparse_point(rpbuf, *rpbuflen_p, &link)) {
 770                 /* Couldn't understand the reparse data; don't do the fixup.  */
 771                 return 0;
 772         }
 773
 774         /*
 775          * Don't do reparse point fixups on relative symbolic links.
 776          *
 777          * On Windows, a relative symbolic link is supposed to be identifiable
 778          * by having reparse tag WIM_IO_REPARSE_TAG_SYMLINK and flags
 779          * SYMBOLIC_LINK_RELATIVE.  We will use this information, although this
 780          * may not always do what the user expects, since drive-relative
 781          * symbolic links such as "\Users\Public" have SYMBOLIC_LINK_RELATIVE
 782          * set, in addition to truly relative symbolic links such as "Users" or
 783          * "Users\Public".  However, WIMGAPI (as of Windows 8.1) has this same
 784          * behavior.
 785          *
 786          * Otherwise, as far as I can tell, the targets of symbolic links that
 787          * are NOT relative, as well as junctions (note: a mountpoint is the
 788          * sames thing as a junction), must be NT namespace paths, for example:
 789          *
 790          *     - \??\e:\Users\Public
 791          *     - \DosDevices\e:\Users\Public
 792          *     - \Device\HardDiskVolume4\Users\Public
 793          *     - \??\Volume{c47cb07c-946e-4155-b8f7-052e9cec7628}\Users\Public
 794          *     - \DosDevices\Volume{c47cb07c-946e-4155-b8f7-052e9cec7628}\Users\Public
 795          */
 796         if (link_is_relative_symlink(&link))
 797                 return 0;
 798
 799         rel_target = winnt_relativize_link_target(link.substitute_name,
 800                                                   link.substitute_name_nbytes,
 801                                                   params->capture_root_ino,
 802                                                   params->capture_root_dev);
 803
 804         if (rel_target == link.substitute_name) {
 805                 /* Target points outside of the tree being captured or had an
 806                  * unrecognized path format.  Don't adjust it.  */
 807                 return winnt_rpfix_progress(params, path, &link,
 808                                             WIMLIB_SCAN_DENTRY_NOT_FIXED_SYMLINK);
 809         }
 810
 811         /* We have an absolute target pointing within the directory being
 812          * captured. @rel_target is the suffix of the link target that is the
 813          * part relative to the directory being captured.
 814          *
 815          * We will cut off the prefix before this part (which is the path to the
 816          * directory being captured) and add a dummy prefix.  Since the process
 817          * will need to be reversed when applying the image, it doesn't matter
 818          * what exactly the prefix is, as long as it looks like an absolute
 819          * path.  */
 820
 821         static const wchar_t prefix[6] = L"\\??\\X:";
 822         static const size_t num_unprintable_chars = 4;
 823
 824         size_t rel_target_nbytes =
 825                 link.substitute_name_nbytes - ((const u8 *)rel_target -
 826                                                (const u8 *)link.substitute_name);
 827
 828         wchar_t tmp[(sizeof(prefix) + rel_target_nbytes) / sizeof(wchar_t)];
 829
 830         memcpy(tmp, prefix, sizeof(prefix));
 831         memcpy(tmp + ARRAY_LEN(prefix), rel_target, rel_target_nbytes);
 832
 833         link.substitute_name = tmp;
 834         link.substitute_name_nbytes = sizeof(tmp);
 835
 836         link.print_name = link.substitute_name + num_unprintable_chars;
 837         link.print_name_nbytes = link.substitute_name_nbytes -
 838                                  (num_unprintable_chars * sizeof(wchar_t));
 839
 840         if (make_link_reparse_point(&link, rpbuf, rpbuflen_p))
 841                 return 0;
 842
 843         ret = winnt_rpfix_progress(params, path, &link,
 844                                    WIMLIB_SCAN_DENTRY_FIXED_SYMLINK);
 845         if (ret)
 846                 return ret;
 847         return RP_FIXED;
 848 }
 849
 850 /* Load the reparse data of a file into the corresponding WIM inode.  If the
 851  * reparse point is a symbolic link or junction with an absolute target and
 852  * RPFIX mode is enabled, then also rewrite its target to be relative to the
 853  * capture root.  */
 854 static noinline_for_stack int
 855 winnt_load_reparse_data(HANDLE h, struct wim_inode *inode,
 856                         const wchar_t *full_path, struct capture_params *params)
 857 {
 858         struct reparse_buffer_disk rpbuf;
 859         DWORD bytes_returned;
 860         u16 rpbuflen;
 861         int ret;
 862
 863         if (inode->i_attributes & FILE_ATTRIBUTE_ENCRYPTED) {
 864                 /* See comment above assign_stream_types_encrypted()  */
 865                 WARNING("Ignoring reparse data of encrypted file \"%ls\"",
 866                         printable_path(full_path));
 867                 return 0;
 868         }
 869
 870         if (!DeviceIoControl(h, FSCTL_GET_REPARSE_POINT,
 871                              NULL, 0, &rpbuf, REPARSE_POINT_MAX_SIZE,
 872                              &bytes_returned, NULL))
 873         {
 874                 win32_error(GetLastError(), L"\"%ls\": Can't get reparse point",
 875                             printable_path(full_path));
 876                 return WIMLIB_ERR_READLINK;
 877         }
 878
 879         rpbuflen = bytes_returned;
 880
 881         if (unlikely(rpbuflen < REPARSE_DATA_OFFSET)) {
 882                 ERROR("\"%ls\": reparse point buffer is too short",
 883                       printable_path(full_path));
 884                 return WIMLIB_ERR_INVALID_REPARSE_DATA;
 885         }
 886
 887         if (params->add_flags & WIMLIB_ADD_FLAG_RPFIX) {
 888                 ret = winnt_try_rpfix(&rpbuf, &rpbuflen, full_path, params);
 889                 if (ret == RP_FIXED)
 890                         inode->i_rp_flags &= ~WIM_RP_FLAG_NOT_FIXED;
 891                 else if (ret)
 892                         return ret;
 893         }
 894
 895         inode->i_reparse_tag = le32_to_cpu(rpbuf.rptag);
 896         inode->i_rp_reserved = le16_to_cpu(rpbuf.rpreserved);
 897
 898         if (!inode_add_stream_with_data(inode,
 899                                         STREAM_TYPE_REPARSE_POINT,
 900                                         NO_STREAM_NAME,
 901                                         rpbuf.rpdata,
 902                                         rpbuflen - REPARSE_DATA_OFFSET,
 903                                         params->blob_table))
 904                 return WIMLIB_ERR_NOMEM;
 905
 906         return 0;
 907 }
 908
 909 static DWORD WINAPI
 910 win32_tally_encrypted_size_cb(unsigned char *_data, void *_size_ret,
 911                               unsigned long len)
 912 {
 913         *(u64*)_size_ret += len;
 914         return ERROR_SUCCESS;
 915 }
 916
 917 static int
 918 win32_get_encrypted_file_size(const wchar_t *path, bool is_dir, u64 *size_ret)
 919 {
 920         DWORD err;
 921         void *file_ctx;
 922         int ret;
 923         DWORD flags = 0;
 924
 925         if (is_dir)
 926                 flags |= CREATE_FOR_DIR;
 927
 928         err = OpenEncryptedFileRaw(path, flags, &file_ctx);
 929         if (err != ERROR_SUCCESS) {
 930                 win32_error(err,
 931                             L"Failed to open encrypted file \"%ls\" for raw read",
 932                             printable_path(path));
 933                 return WIMLIB_ERR_OPEN;
 934         }
 935         *size_ret = 0;
 936         err = ReadEncryptedFileRaw(win32_tally_encrypted_size_cb,
 937                                    size_ret, file_ctx);
 938         if (err != ERROR_SUCCESS) {
 939                 win32_error(err,
 940                             L"Failed to read raw encrypted data from \"%ls\"",
 941                             printable_path(path));
 942                 ret = WIMLIB_ERR_READ;
 943         } else {
 944                 ret = 0;
 945         }
 946         CloseEncryptedFileRaw(file_ctx);
 947         return ret;
 948 }
 949
 950 static int
 951 winnt_scan_efsrpc_raw_data(struct wim_inode *inode,
 952                            wchar_t *path, size_t path_nchars,
 953                            struct list_head *unhashed_blobs,
 954                            struct vss_snapshot *snapshot)
 955 {
 956         const bool is_dir = (inode->i_attributes & FILE_ATTRIBUTE_DIRECTORY);
 957         u64 size;
 958         int ret;
 959
 960         /* OpenEncryptedFileRaw() expects a Win32 name.  */
 961         wimlib_assert(!wmemcmp(path, L"\\??\\", 4));
 962         path[1] = L'\\';
 963
 964         ret = win32_get_encrypted_file_size(path, is_dir, &size);
 965         if (ret)
 966                 goto out;
 967
 968         /* Empty EFSRPC data does not make sense  */
 969         wimlib_assert(size != 0);
 970
 971         ret = add_stream(inode, true, snapshot, size,
 972                          path, path_nchars,
 973                          STREAM_TYPE_EFSRPC_RAW_DATA, NO_STREAM_NAME, 0,
 974                          unhashed_blobs);
 975 out:
 976         path[1] = L'?';
 977         return ret;
 978 }
 979
 980 static bool
 981 get_data_stream_name(wchar_t *raw_stream_name, size_t raw_stream_name_nchars,
 982                      wchar_t **stream_name_ret, size_t *stream_name_nchars_ret)
 983 {
 984         const wchar_t *sep, *type, *end;
 985
 986         /* The stream name should be returned as :NAME:TYPE  */
 987         if (raw_stream_name_nchars < 1)
 988                 return false;
 989         if (raw_stream_name[0] != L':')
 990                 return false;
 991
 992         raw_stream_name++;
 993         raw_stream_name_nchars--;
 994
 995         end = raw_stream_name + raw_stream_name_nchars;
 996
 997         sep = wmemchr(raw_stream_name, L':', raw_stream_name_nchars);
 998         if (!sep)
 999                 return false;
1000
1001         type = sep + 1;
1002         if (end - type != 5)
1003                 return false;
1004
1005         if (wmemcmp(type, L"$DATA", 5))
1006                 return false;
1007
1008         *stream_name_ret = raw_stream_name;
1009         *stream_name_nchars_ret = sep - raw_stream_name;
1010         return true;
1011 }
1012
1013 static int
1014 winnt_scan_data_stream(const wchar_t *path, size_t path_nchars,
1015                        wchar_t *raw_stream_name, size_t raw_stream_name_nchars,
1016                        u64 stream_size,
1017                        struct wim_inode *inode, struct list_head *unhashed_blobs,
1018                        struct vss_snapshot *snapshot)
1019 {
1020         wchar_t *stream_name;
1021         size_t stream_name_nchars;
1022
1023         /* Given the raw stream name (which is something like
1024          * :streamname:$DATA), extract just the stream name part (streamname).
1025          * Ignore any non-$DATA streams.  */
1026         if (!get_data_stream_name(raw_stream_name, raw_stream_name_nchars,
1027                                   &stream_name, &stream_name_nchars))
1028                 return 0;
1029
1030         stream_name[stream_name_nchars] = L'\0';
1031
1032         return add_stream(inode, false, snapshot, stream_size,
1033                           path, path_nchars,
1034                           STREAM_TYPE_DATA, stream_name, stream_name_nchars,
1035                           unhashed_blobs);
1036 }
1037
1038 /*
1039  * Load information about the data streams of an open file into a WIM inode.
1040  *
1041  * We use the NtQueryInformationFile() system call instead of FindFirstStream()
1042  * and FindNextStream().  This is done for two reasons:
1043  *
1044  * - FindFirstStream() opens its own handle to the file or directory and
1045  *   apparently does so without specifying FILE_FLAG_BACKUP_SEMANTICS, thereby
1046  *   causing access denied errors on certain files (even when running as the
1047  *   Administrator).
1048  * - FindFirstStream() and FindNextStream() is only available on Windows Vista
1049  *   and later, whereas the stream support in NtQueryInformationFile() was
1050  *   already present in Windows XP.
1051  */
1052 static noinline_for_stack int
1053 winnt_scan_data_streams(HANDLE h, const wchar_t *path, size_t path_nchars,
1054                         struct wim_inode *inode, struct list_head *unhashed_blobs,
1055                         u64 file_size, u32 vol_flags,
1056                         struct vss_snapshot *snapshot)
1057 {
1058         int ret;
1059         u8 _buf[4096] _aligned_attribute(8);
1060         u8 *buf;
1061         size_t bufsize;
1062         IO_STATUS_BLOCK iosb;
1063         NTSTATUS status;
1064         FILE_STREAM_INFORMATION *info;
1065
1066         buf = _buf;
1067         bufsize = sizeof(_buf);
1068
1069         if (!(vol_flags & FILE_NAMED_STREAMS))
1070                 goto unnamed_only;
1071
1072         /* Get a buffer containing the stream information.  */
1073         while (!NT_SUCCESS(status = (*func_NtQueryInformationFile)(h,
1074                                                                    &iosb,
1075                                                                    buf,
1076                                                                    bufsize,
1077                                                                    FileStreamInformation)))
1078         {
1079
1080                 switch (status) {
1081                 case STATUS_BUFFER_OVERFLOW:
1082                         {
1083                                 u8 *newbuf;
1084
1085                                 bufsize *= 2;
1086                                 if (buf == _buf)
1087                                         newbuf = MALLOC(bufsize);
1088                                 else
1089                                         newbuf = REALLOC(buf, bufsize);
1090                                 if (!newbuf) {
1091                                         ret = WIMLIB_ERR_NOMEM;
1092                                         goto out_free_buf;
1093                                 }
1094                                 buf = newbuf;
1095                         }
1096                         break;
1097                 case STATUS_NOT_IMPLEMENTED:
1098                 case STATUS_NOT_SUPPORTED:
1099                 case STATUS_INVALID_INFO_CLASS:
1100                         goto unnamed_only;
1101                 default:
1102                         winnt_error(status,
1103                                     L"\"%ls\": Failed to query stream information",
1104                                     printable_path(path));
1105                         ret = WIMLIB_ERR_READ;
1106                         goto out_free_buf;
1107                 }
1108         }
1109
1110         if (iosb.Information == 0) {
1111                 /* No stream information.  */
1112                 ret = 0;
1113                 goto out_free_buf;
1114         }
1115
1116         /* Parse one or more stream information structures.  */
1117         info = (FILE_STREAM_INFORMATION *)buf;
1118         for (;;) {
1119                 /* Load the stream information.  */
1120                 ret = winnt_scan_data_stream(path, path_nchars,
1121                                              info->StreamName,
1122                                              info->StreamNameLength / 2,
1123                                              info->StreamSize.QuadPart,
1124                                              inode, unhashed_blobs,
1125                                              snapshot);
1126                 if (ret)
1127                         goto out_free_buf;
1128
1129                 if (info->NextEntryOffset == 0) {
1130                         /* No more stream information.  */
1131                         break;
1132                 }
1133                 /* Advance to next stream information.  */
1134                 info = (FILE_STREAM_INFORMATION *)
1135                                 ((u8 *)info + info->NextEntryOffset);
1136         }
1137         ret = 0;
1138         goto out_free_buf;
1139
1140 unnamed_only:
1141         /* The volume does not support named streams.  Only capture the unnamed
1142          * data stream.  */
1143         if (inode->i_attributes & (FILE_ATTRIBUTE_DIRECTORY |
1144                                    FILE_ATTRIBUTE_REPARSE_POINT))
1145         {
1146                 ret = 0;
1147                 goto out_free_buf;
1148         }
1149
1150         {
1151                 wchar_t stream_name[] = L"::$DATA";
1152                 ret = winnt_scan_data_stream(path, path_nchars, stream_name, 7,
1153                                              file_size, inode, unhashed_blobs,
1154                                              snapshot);
1155         }
1156 out_free_buf:
1157         /* Free buffer if allocated on heap.  */
1158         if (unlikely(buf != _buf))
1159                 FREE(buf);
1160         return ret;
1161 }
1162
1163 static noinline_for_stack u64
1164 get_sort_key(HANDLE h)
1165 {
1166         STARTING_VCN_INPUT_BUFFER in = { .StartingVcn.QuadPart = 0 };
1167         RETRIEVAL_POINTERS_BUFFER out;
1168         DWORD bytesReturned;
1169
1170         if (!DeviceIoControl(h, FSCTL_GET_RETRIEVAL_POINTERS,
1171                              &in, sizeof(in),
1172                              &out, sizeof(out),
1173                              &bytesReturned, NULL))
1174                 return 0;
1175
1176         if (out.ExtentCount < 1)
1177                 return 0;
1178
1179         return out.Extents[0].Lcn.QuadPart;
1180 }
1181
1182 static void
1183 set_sort_key(struct wim_inode *inode, u64 sort_key)
1184 {
1185         for (unsigned i = 0; i < inode->i_num_streams; i++) {
1186                 struct wim_inode_stream *strm = &inode->i_streams[i];
1187                 struct blob_descriptor *blob = stream_blob_resolved(strm);
1188                 if (blob && blob->blob_location == BLOB_IN_WINDOWS_FILE)
1189                         blob->windows_file->sort_key = sort_key;
1190         }
1191 }
1192
1193 static inline bool
1194 should_try_to_use_wimboot_hash(const struct wim_inode *inode,
1195                                const struct winnt_scan_ctx *ctx,
1196                                const struct capture_params *params)
1197 {
1198         /* Directories and encrypted files aren't valid for external backing. */
1199         if (inode->i_attributes & (FILE_ATTRIBUTE_DIRECTORY |
1200                                    FILE_ATTRIBUTE_ENCRYPTED))
1201                 return false;
1202
1203         /* If the file is a reparse point, then try the hash fixup if it's a WOF
1204          * reparse point and we're in WIMBOOT mode.  Otherwise, try the hash
1205          * fixup if WOF may be attached. */
1206         if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT)
1207                 return (inode->i_reparse_tag == WIM_IO_REPARSE_TAG_WOF) &&
1208                         (params->add_flags & WIMLIB_ADD_FLAG_WIMBOOT);
1209         return !ctx->wof_not_attached;
1210 }
1211
1212 /*
1213  * This function implements an optimization for capturing files from a
1214  * filesystem with a backing WIM(s).  If a file is WIM-backed, then we can
1215  * retrieve the SHA-1 message digest of its original contents from its reparse
1216  * point.  This may eliminate the need to read the file's data and/or allow the
1217  * file's data to be immediately deduplicated with existing data in the WIM.
1218  *
1219  * If WOF is attached, then this function is merely an optimization, but
1220  * potentially a very effective one.  If WOF is detached, then this function
1221  * really causes WIM-backed files to be, effectively, automatically
1222  * "dereferenced" when possible; the unnamed data stream is updated to reference
1223  * the original contents and the reparse point is removed.
1224  *
1225  * This function returns 0 if the fixup succeeded or was intentionally not
1226  * executed.  Otherwise it returns an error code.
1227  */
1228 static noinline_for_stack int
1229 try_to_use_wimboot_hash(HANDLE h, struct wim_inode *inode,
1230                         struct blob_table *blob_table,
1231                         struct winnt_scan_ctx *ctx, const wchar_t *full_path)
1232 {
1233         struct wim_inode_stream *reparse_strm = NULL;
1234         struct wim_inode_stream *strm;
1235         struct blob_descriptor *blob;
1236         u8 hash[SHA1_HASH_SIZE];
1237         int ret;
1238
1239         if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT) {
1240                 struct reparse_buffer_disk rpbuf;
1241                 struct {
1242                         struct wof_external_info wof_info;
1243                         struct wim_provider_rpdata wim_info;
1244                 } *rpdata = (void *)rpbuf.rpdata;
1245                 struct blob_descriptor *reparse_blob;
1246
1247                 /* The file has a WOF reparse point, so WOF must be detached.
1248                  * We can read the reparse point directly.  */
1249                 ctx->wof_not_attached = true;
1250                 reparse_strm = inode_get_unnamed_stream(inode, STREAM_TYPE_REPARSE_POINT);
1251                 reparse_blob = stream_blob_resolved(reparse_strm);
1252
1253                 if (!reparse_blob || reparse_blob->size < sizeof(*rpdata))
1254                         return 0;  /* Not a WIM-backed file  */
1255
1256                 ret = read_blob_into_buf(reparse_blob, rpdata);
1257                 if (ret)
1258                         return ret;
1259
1260                 if (rpdata->wof_info.version != WOF_CURRENT_VERSION ||
1261                     rpdata->wof_info.provider != WOF_PROVIDER_WIM ||
1262                     rpdata->wim_info.version != 2)
1263                         return 0;  /* Not a WIM-backed file  */
1264
1265                 /* Okay, this is a WIM backed file.  Get its SHA-1 hash.  */
1266                 copy_hash(hash, rpdata->wim_info.unnamed_data_stream_hash);
1267         } else {
1268                 struct {
1269                         struct wof_external_info wof_info;
1270                         struct wim_provider_external_info wim_info;
1271                 } out;
1272                 IO_STATUS_BLOCK iosb;
1273                 NTSTATUS status;
1274
1275                 /* WOF may be attached.  Try reading this file's external
1276                  * backing info.  */
1277                 status = (*func_NtFsControlFile)(h, NULL, NULL, NULL, &iosb,
1278                                                  FSCTL_GET_EXTERNAL_BACKING,
1279                                                  NULL, 0, &out, sizeof(out));
1280
1281                 /* Is WOF not attached?  */
1282                 if (status == STATUS_INVALID_DEVICE_REQUEST ||
1283                     status == STATUS_NOT_SUPPORTED) {
1284                         ctx->wof_not_attached = true;
1285                         return 0;
1286                 }
1287
1288                 /* Is this file not externally backed?  */
1289                 if (status == STATUS_OBJECT_NOT_EXTERNALLY_BACKED)
1290                         return 0;
1291
1292                 /* Does this file have an unknown type of external backing that
1293                  * needed a larger information buffer?  */
1294                 if (status == STATUS_BUFFER_TOO_SMALL)
1295                         return 0;
1296
1297                 /* Was there some other failure?  */
1298                 if (status != STATUS_SUCCESS) {
1299                         winnt_error(status,
1300                                     L"\"%ls\": FSCTL_GET_EXTERNAL_BACKING failed",
1301                                     full_path);
1302                         return WIMLIB_ERR_STAT;
1303                 }
1304
1305                 /* Is this file backed by a WIM?  */
1306                 if (out.wof_info.version != WOF_CURRENT_VERSION ||
1307                     out.wof_info.provider != WOF_PROVIDER_WIM ||
1308                     out.wim_info.version != WIM_PROVIDER_CURRENT_VERSION)
1309                         return 0;
1310
1311                 /* Okay, this is a WIM backed file.  Get its SHA-1 hash.  */
1312                 copy_hash(hash, out.wim_info.unnamed_data_stream_hash);
1313         }
1314
1315         /* If the file's unnamed data stream is nonempty, then fill in its hash
1316          * and deduplicate it if possible.
1317          *
1318          * With WOF detached, we require that the blob *must* de-duplicable for
1319          * any action can be taken, since without WOF we can't fall back to
1320          * getting the "dereferenced" data by reading the stream (the real
1321          * stream is sparse and contains all zeroes).  */
1322         strm = inode_get_unnamed_data_stream(inode);
1323         if (strm && (blob = stream_blob_resolved(strm))) {
1324                 struct blob_descriptor **back_ptr;
1325
1326                 if (reparse_strm && !lookup_blob(blob_table, hash))
1327                         return 0;
1328                 back_ptr = retrieve_pointer_to_unhashed_blob(blob);
1329                 copy_hash(blob->hash, hash);
1330                 if (after_blob_hashed(blob, back_ptr, blob_table) != blob)
1331                         free_blob_descriptor(blob);
1332         }
1333
1334         /* Remove the reparse point, if present.  */
1335         if (reparse_strm) {
1336                 inode_remove_stream(inode, reparse_strm, blob_table);
1337                 inode->i_attributes &= ~(FILE_ATTRIBUTE_REPARSE_POINT |
1338                                          FILE_ATTRIBUTE_SPARSE_FILE);
1339                 if (inode->i_attributes == 0)
1340                         inode->i_attributes = FILE_ATTRIBUTE_NORMAL;
1341         }
1342
1343         return 0;
1344 }
1345
1346 static noinline_for_stack u32
1347 get_volume_information(HANDLE h, const wchar_t *full_path,
1348                        struct capture_params *params)
1349 {
1350         FILE_FS_ATTRIBUTE_INFORMATION attr_info;
1351         FILE_FS_VOLUME_INFORMATION vol_info;
1352         IO_STATUS_BLOCK iosb;
1353         NTSTATUS status;
1354         u32 vol_flags;
1355
1356         /* Get volume flags  */
1357         status = (*func_NtQueryVolumeInformationFile)(h, &iosb,
1358                                                       &attr_info,
1359                                                       sizeof(attr_info),
1360                                                       FileFsAttributeInformation);
1361         if (likely((NT_SUCCESS(status) || status == STATUS_BUFFER_OVERFLOW) &&
1362                    (iosb.Information >=
1363                         offsetof(FILE_FS_ATTRIBUTE_INFORMATION,
1364                                  FileSystemAttributes) +
1365                         sizeof(attr_info.FileSystemAttributes))))
1366         {
1367                 vol_flags = attr_info.FileSystemAttributes;
1368         } else {
1369                 winnt_warning(status, L"\"%ls\": Can't get volume attributes",
1370                               printable_path(full_path));
1371                 vol_flags = 0;
1372         }
1373
1374         /* Get volume ID.  */
1375         status = (*func_NtQueryVolumeInformationFile)(h, &iosb,
1376                                                       &vol_info,
1377                                                       sizeof(vol_info),
1378                                                       FileFsVolumeInformation);
1379         if (likely((NT_SUCCESS(status) || status == STATUS_BUFFER_OVERFLOW) &&
1380                    (iosb.Information >=
1381                         offsetof(FILE_FS_VOLUME_INFORMATION,
1382                                  VolumeSerialNumber) +
1383                         sizeof(vol_info.VolumeSerialNumber))))
1384         {
1385                 params->capture_root_dev = vol_info.VolumeSerialNumber;
1386         } else {
1387                 winnt_warning(status, L"\"%ls\": Can't get volume ID",
1388                               printable_path(full_path));
1389                 params->capture_root_dev = 0;
1390         }
1391         return vol_flags;
1392 }
1393
1394 struct file_info {
1395         u32 attributes;
1396         u32 num_links;
1397         u64 creation_time;
1398         u64 last_write_time;
1399         u64 last_access_time;
1400         u64 ino;
1401         u64 end_of_file;
1402 };
1403
1404 static noinline_for_stack NTSTATUS
1405 get_file_info(HANDLE h, struct file_info *info)
1406 {
1407         IO_STATUS_BLOCK iosb;
1408         NTSTATUS status;
1409         FILE_ALL_INFORMATION all_info;
1410
1411         status = (*func_NtQueryInformationFile)(h, &iosb, &all_info,
1412                                                 sizeof(all_info),
1413                                                 FileAllInformation);
1414
1415         if (unlikely(!NT_SUCCESS(status) && status != STATUS_BUFFER_OVERFLOW))
1416                 return status;
1417
1418         info->attributes = all_info.BasicInformation.FileAttributes;
1419         info->num_links = all_info.StandardInformation.NumberOfLinks;
1420         info->creation_time = all_info.BasicInformation.CreationTime.QuadPart;
1421         info->last_write_time = all_info.BasicInformation.LastWriteTime.QuadPart;
1422         info->last_access_time = all_info.BasicInformation.LastAccessTime.QuadPart;
1423         info->ino = all_info.InternalInformation.IndexNumber.QuadPart;
1424         info->end_of_file = all_info.StandardInformation.EndOfFile.QuadPart;
1425         return STATUS_SUCCESS;
1426 }
1427
1428 static int
1429 winnt_build_dentry_tree_recursive(struct wim_dentry **root_ret,
1430                                   HANDLE cur_dir,
1431                                   wchar_t *full_path,
1432                                   size_t full_path_nchars,
1433                                   const wchar_t *filename,
1434                                   size_t filename_nchars,
1435                                   struct capture_params *params,
1436                                   struct winnt_scan_ctx *ctx)
1437 {
1438         struct wim_dentry *root = NULL;
1439         struct wim_inode *inode = NULL;
1440         HANDLE h = NULL;
1441         int ret;
1442         NTSTATUS status;
1443         struct file_info file_info;
1444         ACCESS_MASK requestedPerms;
1445         u64 sort_key;
1446
1447         ret = try_exclude(full_path, params);
1448         if (unlikely(ret < 0)) /* Excluded? */
1449                 goto out_progress;
1450         if (unlikely(ret > 0)) /* Error? */
1451                 goto out;
1452
1453         /* Open the file.  */
1454         requestedPerms = FILE_READ_DATA |
1455                          FILE_READ_ATTRIBUTES |
1456                          READ_CONTROL |
1457                          ACCESS_SYSTEM_SECURITY |
1458                          SYNCHRONIZE;
1459 retry_open:
1460         status = winnt_openat(cur_dir,
1461                               (cur_dir ? filename : full_path),
1462                               (cur_dir ? filename_nchars : full_path_nchars),
1463                               requestedPerms,
1464                               &h);
1465         if (unlikely(!NT_SUCCESS(status))) {
1466                 if (status == STATUS_DELETE_PENDING) {
1467                         WARNING("\"%ls\": Deletion pending; skipping file",
1468                                 printable_path(full_path));
1469                         ret = 0;
1470                         goto out;
1471                 }
1472                 if (status == STATUS_ACCESS_DENIED &&
1473                     (requestedPerms & FILE_READ_DATA)) {
1474                         /* This happens on encrypted files.  */
1475                         requestedPerms &= ~FILE_READ_DATA;
1476                         goto retry_open;
1477                 }
1478
1479                 winnt_error(status, L"\"%ls\": Can't open file",
1480                             printable_path(full_path));
1481                 if (status == STATUS_FVE_LOCKED_VOLUME)
1482                         ret = WIMLIB_ERR_FVE_LOCKED_VOLUME;
1483                 else
1484                         ret = WIMLIB_ERR_OPEN;
1485                 goto out;
1486         }
1487
1488         /* Get information about the file.  */
1489         status = get_file_info(h, &file_info);
1490         if (!NT_SUCCESS(status)) {
1491                 winnt_error(status, L"\"%ls\": Can't get file information",
1492                             printable_path(full_path));
1493                 ret = WIMLIB_ERR_STAT;
1494                 goto out;
1495         }
1496
1497         if (unlikely(!(requestedPerms & FILE_READ_DATA)) &&
1498             !(file_info.attributes & FILE_ATTRIBUTE_ENCRYPTED))
1499         {
1500                 ERROR("\"%ls\": Permission to read data was denied",
1501                       printable_path(full_path));
1502                 ret = WIMLIB_ERR_OPEN;
1503                 goto out;
1504         }
1505
1506         if (unlikely(!cur_dir)) {
1507                 /* Root of tree being captured; get volume information.  */
1508                 ctx->vol_flags = get_volume_information(h, full_path, params);
1509                 params->capture_root_ino = file_info.ino;
1510         }
1511
1512
1513         /* Create a WIM dentry with an associated inode, which may be shared.
1514          *
1515          * However, we need to explicitly check for directories and files with
1516          * only 1 link and refuse to hard link them.  This is because Windows
1517          * has a bug where it can return duplicate File IDs for files and
1518          * directories on the FAT filesystem.
1519          *
1520          * Since we don't follow mount points on Windows, we don't need to query
1521          * the volume ID per-file.  Just once, for the root, is enough.  But we
1522          * can't simply pass 0, because then there could be inode collisions
1523          * among multiple calls to win32_build_dentry_tree() that are scanning
1524          * files on different volumes.  */
1525         ret = inode_table_new_dentry(params->inode_table,
1526                                      filename,
1527                                      file_info.ino,
1528                                      params->capture_root_dev,
1529                                      (file_info.num_links <= 1),
1530                                      &root);
1531         if (ret)
1532                 goto out;
1533
1534         /* Get the short (DOS) name of the file.  */
1535         status = winnt_get_short_name(h, root);
1536
1537         /* If we can't read the short filename for any reason other than
1538          * out-of-memory, just ignore the error and assume the file has no short
1539          * name.  This shouldn't be an issue, since the short names are
1540          * essentially obsolete anyway.  */
1541         if (unlikely(status == STATUS_NO_MEMORY)) {
1542                 ret = WIMLIB_ERR_NOMEM;
1543                 goto out;
1544         }
1545
1546         inode = root->d_inode;
1547
1548         if (inode->i_nlink > 1) {
1549                 /* Shared inode (hard link); skip reading per-inode information.
1550                  */
1551                 goto out_progress;
1552         }
1553
1554         inode->i_attributes = file_info.attributes;
1555         inode->i_creation_time = file_info.creation_time;
1556         inode->i_last_write_time = file_info.last_write_time;
1557         inode->i_last_access_time = file_info.last_access_time;
1558
1559         /* Get the file's security descriptor, unless we are capturing in
1560          * NO_ACLS mode or the volume does not support security descriptors.  */
1561         if (!(params->add_flags & WIMLIB_ADD_FLAG_NO_ACLS)
1562             && (ctx->vol_flags & FILE_PERSISTENT_ACLS))
1563         {
1564                 status = winnt_get_security_descriptor(h, inode,
1565                                                        params->sd_set, ctx,
1566                                                        params->add_flags);
1567                 if (!NT_SUCCESS(status)) {
1568                         winnt_error(status,
1569                                     L"\"%ls\": Can't read security descriptor",
1570                                     printable_path(full_path));
1571                         ret = WIMLIB_ERR_STAT;
1572                         goto out;
1573                 }
1574         }
1575
1576         /* If this is a reparse point, load the reparse data.  */
1577         if (unlikely(inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT)) {
1578                 ret = winnt_load_reparse_data(h, inode, full_path, params);
1579                 if (ret)
1580                         goto out;
1581         }
1582
1583         sort_key = get_sort_key(h);
1584
1585         if (unlikely(inode->i_attributes & FILE_ATTRIBUTE_ENCRYPTED)) {
1586                 /* Load information about the raw encrypted data.  This is
1587                  * needed for any directory or non-directory that has
1588                  * FILE_ATTRIBUTE_ENCRYPTED set.
1589                  *
1590                  * Note: since OpenEncryptedFileRaw() fails with
1591                  * ERROR_SHARING_VIOLATION if there are any open handles to the
1592                  * file, we have to close the file and re-open it later if
1593                  * needed.  */
1594                 (*func_NtClose)(h);
1595                 h = NULL;
1596                 ret = winnt_scan_efsrpc_raw_data(inode,
1597                                                  full_path,
1598                                                  full_path_nchars,
1599                                                  params->unhashed_blobs,
1600                                                  ctx->snapshot);
1601                 if (ret)
1602                         goto out;
1603         } else {
1604                 /*
1605                  * Load information about data streams (unnamed and named).
1606                  *
1607                  * Skip this step for encrypted files, since the data from
1608                  * ReadEncryptedFileRaw() already contains all data streams (and
1609                  * they do in fact all get restored by WriteEncryptedFileRaw().)
1610                  *
1611                  * Note: WIMGAPI (as of Windows 8.1) gets wrong and stores both
1612                  * the EFSRPC data and the named data stream(s)...!
1613                  */
1614                 ret = winnt_scan_data_streams(h,
1615                                               full_path,
1616                                               full_path_nchars,
1617                                               inode,
1618                                               params->unhashed_blobs,
1619                                               file_info.end_of_file,
1620                                               ctx->vol_flags,
1621                                               ctx->snapshot);
1622                 if (ret)
1623                         goto out;
1624         }
1625
1626         if (unlikely(should_try_to_use_wimboot_hash(inode, ctx, params))) {
1627                 ret = try_to_use_wimboot_hash(h, inode, params->blob_table, ctx,
1628                                               full_path);
1629                 if (ret)
1630                         goto out;
1631         }
1632
1633         set_sort_key(inode, sort_key);
1634
1635         if (inode_is_directory(inode)) {
1636
1637                 /* Directory: recurse to children.  */
1638
1639                 if (unlikely(!h)) {
1640                         /* Re-open handle that was closed to read raw encrypted
1641                          * data.  */
1642                         status = winnt_openat(cur_dir,
1643                                               (cur_dir ?
1644                                                filename : full_path),
1645                                               (cur_dir ?
1646                                                filename_nchars : full_path_nchars),
1647                                               FILE_LIST_DIRECTORY | SYNCHRONIZE,
1648                                               &h);
1649                         if (!NT_SUCCESS(status)) {
1650                                 winnt_error(status,
1651                                             L"\"%ls\": Can't re-open file",
1652                                             printable_path(full_path));
1653                                 ret = WIMLIB_ERR_OPEN;
1654                                 goto out;
1655                         }
1656                 }
1657                 ret = winnt_recurse_directory(h,
1658                                               full_path,
1659                                               full_path_nchars,
1660                                               root,
1661                                               params,
1662                                               ctx);
1663                 if (ret)
1664                         goto out;
1665         }
1666
1667 out_progress:
1668         params->progress.scan.cur_path = printable_path(full_path);
1669         if (likely(root))
1670                 ret = do_capture_progress(params, WIMLIB_SCAN_DENTRY_OK, inode);
1671         else
1672                 ret = do_capture_progress(params, WIMLIB_SCAN_DENTRY_EXCLUDED, NULL);
1673 out:
1674         if (likely(h))
1675                 (*func_NtClose)(h);
1676         if (unlikely(ret)) {
1677                 free_dentry_tree(root, params->blob_table);
1678                 root = NULL;
1679                 ret = report_capture_error(params, ret, full_path);
1680         }
1681         *root_ret = root;
1682         return ret;
1683 }
1684
1685 static void
1686 winnt_do_scan_warnings(const wchar_t *path, const struct winnt_scan_ctx *ctx)
1687 {
1688         if (likely(ctx->num_get_sacl_priv_notheld == 0 &&
1689                    ctx->num_get_sd_access_denied == 0))
1690                 return;
1691
1692         WARNING("Scan of \"%ls\" complete, but with one or more warnings:", path);
1693         if (ctx->num_get_sacl_priv_notheld != 0) {
1694                 WARNING("- Could not capture SACL (System Access Control List)\n"
1695                         "            on %lu files or directories.",
1696                         ctx->num_get_sacl_priv_notheld);
1697         }
1698         if (ctx->num_get_sd_access_denied != 0) {
1699                 WARNING("- Could not capture security descriptor at all\n"
1700                         "            on %lu files or directories.",
1701                         ctx->num_get_sd_access_denied);
1702         }
1703         WARNING("To fully capture all security descriptors, run the program\n"
1704                 "          with Administrator rights.");
1705 }
1706
1707 #define WINDOWS_NT_MAX_PATH 32768
1708
1709 /* Win32 version of capturing a directory tree.  */
1710 int
1711 win32_build_dentry_tree(struct wim_dentry **root_ret,
1712                         const wchar_t *root_disk_path,
1713                         struct capture_params *params)
1714 {
1715         wchar_t *path = NULL;
1716         struct winnt_scan_ctx ctx = {};
1717         UNICODE_STRING ntpath;
1718         size_t ntpath_nchars;
1719         int ret;
1720
1721         /* WARNING: There is no check for overflow later when this buffer is
1722          * being used!  But it's as long as the maximum path length understood
1723          * by Windows NT (which is NOT the same as MAX_PATH).  */
1724         path = MALLOC((WINDOWS_NT_MAX_PATH + 1) * sizeof(wchar_t));
1725         if (!path)
1726                 return WIMLIB_ERR_NOMEM;
1727
1728         if (params->add_flags & WIMLIB_ADD_FLAG_SNAPSHOT)
1729                 ret = vss_create_snapshot(root_disk_path, &ntpath, &ctx.snapshot);
1730         else
1731                 ret = win32_path_to_nt_path(root_disk_path, &ntpath);
1732
1733         if (ret)
1734                 goto out;
1735
1736         if (ntpath.Length < 4 * sizeof(wchar_t) ||
1737             ntpath.Length > WINDOWS_NT_MAX_PATH * sizeof(wchar_t) ||
1738             wmemcmp(ntpath.Buffer, L"\\??\\", 4))
1739         {
1740                 ERROR("\"%ls\": unrecognized path format", root_disk_path);
1741                 ret = WIMLIB_ERR_INVALID_PARAM;
1742         } else {
1743                 ntpath_nchars = ntpath.Length / sizeof(wchar_t);
1744                 wmemcpy(path, ntpath.Buffer, ntpath_nchars);
1745                 path[ntpath_nchars] = L'\0';
1746
1747                 params->capture_root_nchars = ntpath_nchars;
1748                 if (path[ntpath_nchars - 1] == L'\\')
1749                         params->capture_root_nchars--;
1750                 ret = 0;
1751         }
1752         HeapFree(GetProcessHeap(), 0, ntpath.Buffer);
1753         if (ret)
1754                 goto out;
1755
1756         ret = winnt_build_dentry_tree_recursive(root_ret, NULL,
1757                                                 path, ntpath_nchars,
1758                                                 L"", 0, params, &ctx);
1759 out:
1760         vss_put_snapshot(ctx.snapshot);
1761         FREE(path);
1762         if (ret == 0)
1763                 winnt_do_scan_warnings(root_disk_path, &ctx);
1764         return ret;
1765 }
1766
1767 #endif /* __WIN32__ */