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1 /*
2  * wim.c - Stuff that doesn't fit into any other file
3  */
4
5 /*
6  * Copyright (C) 2012 Eric Biggers
7  *
8  * wimlib - Library for working with WIM files
9  *
10  * This file is part of wimlib, a library for working with WIM files.
11  *
12  * wimlib is free software; you can redistribute it and/or modify it under the
13  * terms of the GNU General Public License as published by the Free
14  * Software Foundation; either version 3 of the License, or (at your option)
15  * any later version.
16  *
17  * wimlib is distributed in the hope that it will be useful, but WITHOUT ANY
18  * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
19  * A PARTICULAR PURPOSE. See the GNU General Public License for more
20  * details.
21  *
22  * You should have received a copy of the GNU General Public License
23  * along with wimlib; if not, see http://www.gnu.org/licenses/.
24  */
25
26 #include "config.h"
27 #include <limits.h>
28 #include <stdlib.h>
29 #include <stdarg.h>
30 #include <errno.h>
31
32 #include "dentry.h"
33 #include <unistd.h>
34 #include <fcntl.h>
35
36 #ifdef WITH_NTFS_3G
37 #include <time.h>
38 #include <ntfs-3g/volume.h>
39 #endif
40
41 #include "wimlib_internal.h"
42 #include "buffer_io.h"
43 #include "lookup_table.h"
44 #include "xml.h"
45
46 static int image_print_metadata(WIMStruct *w)
47 {
48         DEBUG("Printing metadata for image %d", w->current_image);
49         print_security_data(wim_security_data(w));
50         return for_dentry_in_tree(wim_root_dentry(w), print_dentry,
51                                   w->lookup_table);
52 }
53
54
55 static int image_print_files(WIMStruct *w)
56 {
57         return for_dentry_in_tree(wim_root_dentry(w), print_dentry_full_path,
58                                   NULL);
59 }
60
61 static WIMStruct *new_wim_struct()
62 {
63         WIMStruct *w = CALLOC(1, sizeof(WIMStruct));
64 #ifdef WITH_FUSE
65         if (pthread_mutex_init(&w->fp_tab_mutex, NULL) != 0) {
66                 ERROR_WITH_ERRNO("Failed to initialize mutex");
67                 FREE(w);
68                 w = NULL;
69         }
70 #endif
71         return w;
72
73 }
74
75 /*
76  * Calls a function on images in the WIM.  If @image is WIMLIB_ALL_IMAGES, @visitor
77  * is called on the WIM once for each image, with each image selected as the
78  * current image in turn.  If @image is a certain image, @visitor is called on
79  * the WIM only once, with that image selected.
80  */
81 int for_image(WIMStruct *w, int image, int (*visitor)(WIMStruct *))
82 {
83         int ret;
84         int start;
85         int end;
86         int i;
87
88         if (image == WIMLIB_ALL_IMAGES) {
89                 start = 1;
90                 end = w->hdr.image_count;
91         } else if (image >= 1 && image <= w->hdr.image_count) {
92                 start = image;
93                 end = image;
94         } else {
95                 return WIMLIB_ERR_INVALID_IMAGE;
96         }
97         for (i = start; i <= end; i++) {
98                 ret = select_wim_image(w, i);
99                 if (ret != 0)
100                         return ret;
101                 ret = visitor(w);
102                 if (ret != 0)
103                         return ret;
104         }
105         return 0;
106 }
107
108 static int sort_image_metadata_by_position(const void *p1, const void *p2)
109 {
110         const struct wim_image_metadata *imd1 = p1;
111         const struct wim_image_metadata *imd2 = p2;
112         u64 offset1 = imd1->metadata_lte->resource_entry.offset;
113         u64 offset2 = imd2->metadata_lte->resource_entry.offset;
114         if (offset1 < offset2)
115                 return -1;
116         else if (offset1 > offset2)
117                 return 1;
118         else
119                 return 0;
120 }
121
122 /*
123  * If @lte points to a metadata resource, append it to the list of metadata
124  * resources in the WIMStruct.  Otherwise, do nothing.
125  */
126 static int append_metadata_resource_entry(struct wim_lookup_table_entry *lte,
127                                           void *wim_p)
128 {
129         WIMStruct *w = wim_p;
130         int ret = 0;
131
132         if (lte->resource_entry.flags & WIM_RESHDR_FLAG_METADATA) {
133                 if (w->current_image == w->hdr.image_count) {
134                         ERROR("The WIM header says there are %u images in the WIM,\n"
135                               "        but we found more metadata resources than this",
136                               w->hdr.image_count);
137                         ret = WIMLIB_ERR_IMAGE_COUNT;
138                 } else {
139                         DEBUG("Found metadata resource for image %u at "
140                               "offset %"PRIu64".",
141                               w->current_image + 1,
142                               lte->resource_entry.offset);
143                         w->image_metadata[
144                                 w->current_image++].metadata_lte = lte;
145                 }
146         }
147         return ret;
148 }
149
150 /* Returns the compression type given in the flags of a WIM header. */
151 static int wim_hdr_flags_compression_type(int wim_hdr_flags)
152 {
153         if (wim_hdr_flags & WIM_HDR_FLAG_COMPRESSION) {
154                 if (wim_hdr_flags & WIM_HDR_FLAG_COMPRESS_LZX)
155                         return WIMLIB_COMPRESSION_TYPE_LZX;
156                 else if (wim_hdr_flags & WIM_HDR_FLAG_COMPRESS_XPRESS)
157                         return WIMLIB_COMPRESSION_TYPE_XPRESS;
158                 else
159                         return WIMLIB_COMPRESSION_TYPE_INVALID;
160         } else {
161                 return WIMLIB_COMPRESSION_TYPE_NONE;
162         }
163 }
164
165 /*
166  * Creates a WIMStruct for a new WIM file.
167  */
168 WIMLIBAPI int wimlib_create_new_wim(int ctype, WIMStruct **w_ret)
169 {
170         WIMStruct *w;
171         struct wim_lookup_table *table;
172         int ret;
173
174         DEBUG("Creating new WIM with %s compression.",
175               wimlib_get_compression_type_string(ctype));
176
177         /* Allocate the WIMStruct. */
178         w = new_wim_struct();
179         if (!w)
180                 return WIMLIB_ERR_NOMEM;
181
182         ret = init_header(&w->hdr, ctype);
183         if (ret != 0)
184                 goto out_free;
185
186         table = new_lookup_table(9001);
187         if (!table) {
188                 ret = WIMLIB_ERR_NOMEM;
189                 goto out_free;
190         }
191         w->lookup_table = table;
192         *w_ret = w;
193         return 0;
194 out_free:
195         FREE(w);
196         return ret;
197 }
198
199 WIMLIBAPI int wimlib_get_num_images(const WIMStruct *w)
200 {
201         return w->hdr.image_count;
202 }
203
204 int select_wim_image(WIMStruct *w, int image)
205 {
206         struct wim_image_metadata *imd;
207         int ret;
208
209         DEBUG("Selecting image %d", image);
210
211         if (image == WIMLIB_NO_IMAGE) {
212                 ERROR("Invalid image: %d", WIMLIB_NO_IMAGE);
213                 return WIMLIB_ERR_INVALID_IMAGE;
214         }
215
216         if (image == w->current_image)
217                 return 0;
218
219         if (image < 1 || image > w->hdr.image_count) {
220                 ERROR("Cannot select image %d: There are only %u images",
221                       image, w->hdr.image_count);
222                 return WIMLIB_ERR_INVALID_IMAGE;
223         }
224
225         /* If a valid image is currently selected, it can be freed if it is not
226          * modified.  */
227         if (w->current_image != WIMLIB_NO_IMAGE) {
228                 imd = wim_get_current_image_metadata(w);
229                 if (!imd->modified) {
230                         DEBUG("Freeing image %u", w->current_image);
231                         destroy_image_metadata(imd, NULL);
232                         imd->root_dentry = NULL;
233                         imd->security_data = NULL;
234                         INIT_HLIST_HEAD(&imd->inode_list);
235                 }
236         }
237         w->current_image = image;
238         imd = &w->image_metadata[image - 1];
239         if (imd->root_dentry) {
240                 ret = 0;
241         } else {
242                 #ifdef ENABLE_DEBUG
243                 DEBUG("Reading metadata resource specified by the following "
244                       "lookup table entry:");
245                 print_lookup_table_entry(imd->metadata_lte, stdout);
246                 #endif
247                 ret = read_metadata_resource(w, imd);
248                 if (ret)
249                         w->current_image = WIMLIB_NO_IMAGE;
250         }
251         return ret;
252 }
253
254
255 /* Returns the compression type of the WIM file. */
256 WIMLIBAPI int wimlib_get_compression_type(const WIMStruct *w)
257 {
258         return wim_hdr_flags_compression_type(w->hdr.flags);
259 }
260
261 WIMLIBAPI const char *wimlib_get_compression_type_string(int ctype)
262 {
263         switch (ctype) {
264                 case WIMLIB_COMPRESSION_TYPE_NONE:
265                         return "None";
266                 case WIMLIB_COMPRESSION_TYPE_LZX:
267                         return "LZX";
268                 case WIMLIB_COMPRESSION_TYPE_XPRESS:
269                         return "XPRESS";
270                 default:
271                         return "Invalid";
272         }
273 }
274
275 /*
276  * Returns the number of an image in the WIM file, given a string that is either
277  * the number of the image, or the name of the image.  The images are numbered
278  * starting at 1.
279  */
280 WIMLIBAPI int wimlib_resolve_image(WIMStruct *w, const char *image_name_or_num)
281 {
282         char *p;
283         int image;
284         int i;
285
286         if (!image_name_or_num || !*image_name_or_num)
287                 return WIMLIB_NO_IMAGE;
288
289         if (strcmp(image_name_or_num, "all") == 0
290             || strcmp(image_name_or_num, "*") == 0)
291                 return WIMLIB_ALL_IMAGES;
292         image = strtol(image_name_or_num, &p, 10);
293         if (p != image_name_or_num && *p == '\0' && image > 0) {
294                 if (image > w->hdr.image_count)
295                         return WIMLIB_NO_IMAGE;
296                 return image;
297         } else {
298                 for (i = 1; i <= w->hdr.image_count; i++) {
299                         if (strcmp(image_name_or_num,
300                                    wimlib_get_image_name(w, i)) == 0)
301                                 return i;
302                 }
303                 return WIMLIB_NO_IMAGE;
304         }
305 }
306
307
308 /* Prints some basic information about a WIM file. */
309 WIMLIBAPI void wimlib_print_wim_information(const WIMStruct *w)
310 {
311         const struct wim_header *hdr;
312
313         hdr = &w->hdr;
314         puts("WIM Information:");
315         puts("----------------");
316         printf("Path:           %s\n", w->filename);
317         fputs ("GUID:           0x", stdout);
318         print_byte_field(hdr->guid, WIM_GID_LEN);
319         putchar('\n');
320         printf("Image Count:    %d\n", hdr->image_count);
321         printf("Compression:    %s\n", wimlib_get_compression_type_string(
322                                                 wimlib_get_compression_type(w)));
323         printf("Part Number:    %d/%d\n", hdr->part_number, hdr->total_parts);
324         printf("Boot Index:     %d\n", hdr->boot_idx);
325         printf("Size:           %"PRIu64" bytes\n",
326                                 wim_info_get_total_bytes(w->wim_info));
327         printf("Integrity Info: %s\n", (w->hdr.integrity.offset != 0) ? "yes" : "no");
328         putchar('\n');
329 }
330
331 WIMLIBAPI bool wimlib_has_integrity_table(const WIMStruct *w)
332 {
333         return w->hdr.integrity.size != 0;
334 }
335
336 WIMLIBAPI void wimlib_print_available_images(const WIMStruct *w, int image)
337 {
338         int first;
339         int last;
340         int i;
341         int n;
342         if (image == WIMLIB_ALL_IMAGES) {
343                 n = printf("Available Images:\n");
344                 first = 1;
345                 last = w->hdr.image_count;
346         } else if (image >= 1 && image <= w->hdr.image_count) {
347                 n = printf("Information for Image %d\n", image);
348                 first = image;
349                 last = image;
350         } else {
351                 printf("wimlib_print_available_images(): Invalid image %d",
352                        image);
353                 return;
354         }
355         for (i = 0; i < n - 1; i++)
356                 putchar('-');
357         putchar('\n');
358         for (i = first; i <= last; i++)
359                 print_image_info(w->wim_info, i);
360 }
361
362
363 /* Prints the metadata for the specified image, which may be WIMLIB_ALL_IMAGES, but
364  * not WIMLIB_NO_IMAGE. */
365 WIMLIBAPI int wimlib_print_metadata(WIMStruct *w, int image)
366 {
367         if (w->hdr.part_number != 1) {
368                 ERROR("Cannot show the metadata from part %hu of a %hu-part split WIM!",
369                        w->hdr.part_number, w->hdr.total_parts);
370                 ERROR("Select the first part of the split WIM to see the metadata.");
371                 return WIMLIB_ERR_SPLIT_UNSUPPORTED;
372         }
373         return for_image(w, image, image_print_metadata);
374 }
375
376 WIMLIBAPI int wimlib_print_files(WIMStruct *w, int image)
377 {
378         if (w->hdr.part_number != 1) {
379                 ERROR("Cannot list the files from part %hu of a %hu-part split WIM!",
380                        w->hdr.part_number, w->hdr.total_parts);
381                 ERROR("Select the first part of the split WIM if you'd like to list the files.");
382                 return WIMLIB_ERR_SPLIT_UNSUPPORTED;
383         }
384         return for_image(w, image, image_print_files);
385 }
386
387 /* Sets the index of the bootable image. */
388 WIMLIBAPI int wimlib_set_boot_idx(WIMStruct *w, int boot_idx)
389 {
390         if (w->hdr.total_parts != 1) {
391                 ERROR("Cannot modify the boot index of a split WIM!");
392                 return WIMLIB_ERR_SPLIT_UNSUPPORTED;
393         }
394         if (boot_idx < 0 || boot_idx > w->hdr.image_count)
395                 return WIMLIB_ERR_INVALID_IMAGE;
396         w->hdr.boot_idx = boot_idx;
397
398         if (boot_idx == 0) {
399                 memset(&w->hdr.boot_metadata_res_entry, 0,
400                        sizeof(struct resource_entry));
401         } else {
402                 memcpy(&w->hdr.boot_metadata_res_entry,
403                        &w->image_metadata[
404                           boot_idx - 1].metadata_lte->resource_entry,
405                        sizeof(struct resource_entry));
406         }
407
408         return 0;
409 }
410
411 WIMLIBAPI int wimlib_get_part_number(const WIMStruct *w, int *total_parts_ret)
412 {
413         if (total_parts_ret)
414                 *total_parts_ret = w->hdr.total_parts;
415         return w->hdr.part_number;
416 }
417
418
419 WIMLIBAPI int wimlib_get_boot_idx(const WIMStruct *w)
420 {
421         return w->hdr.boot_idx;
422 }
423
424 /*
425  * Begins the reading of a WIM file; opens the file and reads its header and
426  * lookup table, and optionally checks the integrity.
427  */
428 static int begin_read(WIMStruct *w, const char *in_wim_path, int open_flags,
429                       wimlib_progress_func_t progress_func)
430 {
431         int ret;
432         int xml_num_images;
433
434         DEBUG("Reading the WIM file `%s'", in_wim_path);
435
436         w->fp = fopen(in_wim_path, "rb");
437         if (!w->fp) {
438                 ERROR_WITH_ERRNO("Failed to open `%s' for reading",
439                                  in_wim_path);
440                 return WIMLIB_ERR_OPEN;
441         }
442
443         /* The absolute path to the WIM is requested so that wimlib_overwrite()
444          * still works even if the process changes its working directory.  This
445          * actually happens if a WIM is mounted read-write, since the FUSE
446          * thread changes directory to "/", and it needs to be able to find the
447          * WIM file again.
448          *
449          * This will break if the full path to the WIM changes in the
450          * intervening time...
451          */
452         w->filename = realpath(in_wim_path, NULL);
453         if (!w->filename) {
454                 ERROR_WITH_ERRNO("Failed to resolve WIM filename");
455                 if (errno == ENOMEM)
456                         return WIMLIB_ERR_NOMEM;
457                 else
458                         return WIMLIB_ERR_OPEN;
459         }
460
461         ret = read_header(w->fp, &w->hdr, open_flags);
462         if (ret != 0)
463                 return ret;
464
465         DEBUG("According to header, WIM contains %u images", w->hdr.image_count);
466
467         /* If the boot index is invalid, print a warning and set it to 0 */
468         if (w->hdr.boot_idx > w->hdr.image_count) {
469                 WARNING("In `%s', image %u is marked as bootable, "
470                         "but there are only %u images in the WIM",
471                         in_wim_path, w->hdr.boot_idx, w->hdr.image_count);
472                 w->hdr.boot_idx = 0;
473         }
474
475         if (wimlib_get_compression_type(w) == WIMLIB_COMPRESSION_TYPE_INVALID) {
476                 ERROR("Invalid compression type (WIM header flags = 0x%x)",
477                       w->hdr.flags);
478                 return WIMLIB_ERR_INVALID_COMPRESSION_TYPE;
479         }
480
481         if (open_flags & WIMLIB_OPEN_FLAG_CHECK_INTEGRITY) {
482                 ret = check_wim_integrity(w, progress_func);
483                 if (ret == WIM_INTEGRITY_NONEXISTENT) {
484                         WARNING("No integrity information for `%s'; skipping "
485                                 "integrity check.", in_wim_path);
486                 } else if (ret == WIM_INTEGRITY_NOT_OK) {
487                         ERROR("WIM is not intact! (Failed integrity check)");
488                         return WIMLIB_ERR_INTEGRITY;
489                 } else if (ret != WIM_INTEGRITY_OK) {
490                         return ret;
491                 }
492         }
493
494         ret = read_lookup_table(w);
495         if (ret != 0)
496                 return ret;
497
498         if (w->hdr.image_count != 0) {
499                 w->image_metadata = CALLOC(w->hdr.image_count,
500                                            sizeof(struct wim_image_metadata));
501
502                 if (!w->image_metadata) {
503                         ERROR("Failed to allocate memory for %u image metadata structures",
504                               w->hdr.image_count);
505                         return WIMLIB_ERR_NOMEM;
506                 }
507         }
508         w->current_image = 0;
509
510         DEBUG("Looking for metadata resources in the lookup table.");
511
512         /* Find the images in the WIM by searching the lookup table. */
513         ret = for_lookup_table_entry(w->lookup_table,
514                                      append_metadata_resource_entry, w);
515
516         if (ret != 0)
517                 return ret;
518
519         /* Make sure all the expected images were found.  (We already have
520          * returned WIMLIB_ERR_IMAGE_COUNT if *extra* images were found) */
521         if (w->current_image != w->hdr.image_count &&
522             w->hdr.part_number == 1)
523         {
524                 ERROR("Only found %d images in WIM, but expected %u",
525                       w->current_image, w->hdr.image_count);
526                 return WIMLIB_ERR_IMAGE_COUNT;
527         }
528
529         /* Sort images by the position of their metadata resources.  I'm
530          * assuming that is what determines the other of the images in the WIM
531          * file, rather than their order in the lookup table, which is random
532          * because of hashing. */
533         qsort(w->image_metadata, w->current_image,
534               sizeof(struct wim_image_metadata), sort_image_metadata_by_position);
535
536         w->current_image = WIMLIB_NO_IMAGE;
537
538         /* Read the XML data. */
539         ret = read_xml_data(w->fp, &w->hdr.xml_res_entry,
540                             &w->xml_data, &w->wim_info);
541
542         if (ret != 0)
543                 return ret;
544
545         xml_num_images = wim_info_get_num_images(w->wim_info);
546         if (xml_num_images != w->hdr.image_count) {
547                 ERROR("In the file `%s', there are %u <IMAGE> elements "
548                       "in the XML data,", in_wim_path, xml_num_images);
549                 ERROR("but %u images in the WIM!  There must be exactly one "
550                       "<IMAGE> element per image.", w->hdr.image_count);
551                 return WIMLIB_ERR_IMAGE_COUNT;
552         }
553
554         DEBUG("Done beginning read of WIM file `%s'.", in_wim_path);
555         return 0;
556 }
557
558
559 /*
560  * Opens a WIM file and creates a WIMStruct for it.
561  */
562 WIMLIBAPI int wimlib_open_wim(const char *wim_file, int open_flags,
563                               WIMStruct **w_ret,
564                               wimlib_progress_func_t progress_func)
565 {
566         WIMStruct *w;
567         int ret;
568
569         if (!wim_file || !w_ret)
570                 return WIMLIB_ERR_INVALID_PARAM;
571
572         w = new_wim_struct();
573         if (!w)
574                 return WIMLIB_ERR_NOMEM;
575
576         ret = begin_read(w, wim_file, open_flags, progress_func);
577         if (ret == 0)
578                 *w_ret = w;
579         else
580                 wimlib_free(w);
581         return ret;
582 }
583
584 void destroy_image_metadata(struct wim_image_metadata *imd,
585                             struct wim_lookup_table *table)
586 {
587         free_dentry_tree(imd->root_dentry, table);
588         free_security_data(imd->security_data);
589
590         /* Get rid of the lookup table entry for this image's metadata resource
591          * */
592         if (table) {
593                 lookup_table_unlink(table, imd->metadata_lte);
594                 free_lookup_table_entry(imd->metadata_lte);
595         }
596 }
597
598 /* Frees the memory for the WIMStruct, including all internal memory; also
599  * closes all files associated with the WIMStruct.  */
600 WIMLIBAPI void wimlib_free(WIMStruct *w)
601 {
602         DEBUG2("Freeing WIMStruct");
603
604         if (!w)
605                 return;
606         if (w->fp)
607                 fclose(w->fp);
608         if (w->out_fp)
609                 fclose(w->out_fp);
610
611 #ifdef WITH_FUSE
612         if (w->fp_tab) {
613                 for (size_t i = 0; i < w->num_allocated_fps; i++)
614                         if (w->fp_tab[i])
615                                 fclose(w->fp_tab[i]);
616                 FREE(w->fp_tab);
617         }
618         pthread_mutex_destroy(&w->fp_tab_mutex);
619 #endif
620
621         free_lookup_table(w->lookup_table);
622
623         FREE(w->filename);
624         FREE(w->xml_data);
625         free_wim_info(w->wim_info);
626         if (w->image_metadata) {
627                 for (unsigned i = 0; i < w->hdr.image_count; i++)
628                         destroy_image_metadata(&w->image_metadata[i], NULL);
629                 FREE(w->image_metadata);
630         }
631 #ifdef WITH_NTFS_3G
632         if (w->ntfs_vol) {
633                 DEBUG("Unmounting NTFS volume");
634                 ntfs_umount(w->ntfs_vol, FALSE);
635         }
636 #endif
637         FREE(w);
638 }
639
640 /* Get global memory allocations out of the way.  Not strictly necessary in
641  * single-threaded programs like 'imagex'. */
642 WIMLIBAPI int wimlib_global_init()
643 {
644         libxml_global_init();
645         return iconv_global_init();
646 }
647
648 /* Free global memory allocations.  Not strictly necessary if the process using
649  * wimlib is just about to exit (as is the case for 'imagex'). */
650 WIMLIBAPI void wimlib_global_cleanup()
651 {
652         libxml_global_cleanup();
653         iconv_global_cleanup();
654 }