summaryrefslogtreecommitdiffstats
path: root/lib/libalpm/be_package.c
blob: 9429ad536d4962d240288693c41b2a48afa75dc3 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
/*
 *  be_package.c : backend for packages
 *
 *  Copyright (c) 2006-2020 Pacman Development Team <pacman-dev@archlinux.org>
 *  Copyright (c) 2002-2006 by Judd Vinet <jvinet@zeroflux.org>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <limits.h>

/* libarchive */
#include <archive.h>
#include <archive_entry.h>

/* libalpm */
#include "alpm_list.h"
#include "alpm.h"
#include "libarchive-compat.h"
#include "util.h"
#include "log.h"
#include "handle.h"
#include "package.h"
#include "deps.h"
#include "filelist.h"
#include "util.h"

struct package_changelog {
	struct archive *archive;
	int fd;
};

/**
 * Open a package changelog for reading. Similar to fopen in functionality,
 * except that the returned 'file stream' is from an archive.
 * @param pkg the package (file) to read the changelog
 * @return a 'file stream' to the package changelog
 */
static void *_package_changelog_open(alpm_pkg_t *pkg)
{
	ASSERT(pkg != NULL, return NULL);

	struct package_changelog *changelog;
	struct archive *archive;
	struct archive_entry *entry;
	const char *pkgfile = pkg->origin_data.file;
	struct stat buf;
	int fd;

	fd = _alpm_open_archive(pkg->handle, pkgfile, &buf,
			&archive, ALPM_ERR_PKG_OPEN);
	if(fd < 0) {
		return NULL;
	}

	while(archive_read_next_header(archive, &entry) == ARCHIVE_OK) {
		const char *entry_name = archive_entry_pathname(entry);

		if(strcmp(entry_name, ".CHANGELOG") == 0) {
			changelog = malloc(sizeof(struct package_changelog));
			if(!changelog) {
				pkg->handle->pm_errno = ALPM_ERR_MEMORY;
				_alpm_archive_read_free(archive);
				close(fd);
				return NULL;
			}
			changelog->archive = archive;
			changelog->fd = fd;
			return changelog;
		}
	}
	/* we didn't find a changelog */
	_alpm_archive_read_free(archive);
	close(fd);
	errno = ENOENT;

	return NULL;
}

/**
 * Read data from an open changelog 'file stream'. Similar to fread in
 * functionality, this function takes a buffer and amount of data to read.
 * @param ptr a buffer to fill with raw changelog data
 * @param size the size of the buffer
 * @param pkg the package that the changelog is being read from
 * @param fp a 'file stream' to the package changelog
 * @return the number of characters read, or 0 if there is no more data
 */
static size_t _package_changelog_read(void *ptr, size_t size,
		const alpm_pkg_t UNUSED *pkg, void *fp)
{
	struct package_changelog *changelog = fp;
	ssize_t sret = archive_read_data(changelog->archive, ptr, size);
	/* Report error (negative values) */
	if(sret < 0) {
		RET_ERR(pkg->handle, ALPM_ERR_LIBARCHIVE, 0);
	} else {
		return (size_t)sret;
	}
}

/**
 * Close a package changelog for reading. Similar to fclose in functionality,
 * except that the 'file stream' is from an archive.
 * @param pkg the package (file) that the changelog was read from
 * @param fp a 'file stream' to the package changelog
 * @return whether closing the package changelog stream was successful
 */
static int _package_changelog_close(const alpm_pkg_t UNUSED *pkg, void *fp)
{
	int ret;
	struct package_changelog *changelog = fp;
	ret = _alpm_archive_read_free(changelog->archive);
	close(changelog->fd);
	free(changelog);
	return ret;
}

/** Package file operations struct accessor. We implement this as a method
 * because we want to reuse the majority of the default_pkg_ops struct and
 * add only a few operations of our own on top.
 */
static const struct pkg_operations *get_file_pkg_ops(void)
{
	static struct pkg_operations file_pkg_ops;
	static int file_pkg_ops_initialized = 0;
	if(!file_pkg_ops_initialized) {
		file_pkg_ops = default_pkg_ops;
		file_pkg_ops.changelog_open  = _package_changelog_open;
		file_pkg_ops.changelog_read  = _package_changelog_read;
		file_pkg_ops.changelog_close = _package_changelog_close;
		file_pkg_ops_initialized = 1;
	}
	return &file_pkg_ops;
}

/**
 * Parses the package description file for a package into a alpm_pkg_t struct.
 * @param archive the archive to read from, pointed at the .PKGINFO entry
 * @param newpkg an empty alpm_pkg_t struct to fill with package info
 *
 * @return 0 on success, -1 on error
 */
static int parse_descfile(alpm_handle_t *handle, struct archive *a, alpm_pkg_t *newpkg)
{
	char *ptr = NULL;
	char *key = NULL;
	int ret, linenum = 0;
	struct archive_read_buffer buf = {0};

	/* 512K for a line length seems reasonable */
	buf.max_line_size = 512 * 1024;

	/* loop until we reach EOF or other error */
	while((ret = _alpm_archive_fgets(a, &buf)) == ARCHIVE_OK) {
		size_t len = _alpm_strip_newline(buf.line, buf.real_line_size);

		linenum++;
		key = buf.line;
		if(len == 0 || key[0] == '#') {
			continue;
		}
		/* line is always in this format: "key = value"
		 * we can be sure the " = " exists, so look for that */
		ptr = memchr(key, ' ', len);
		if(!ptr || (size_t)(ptr - key + 2) > len || memcmp(ptr, " = ", 3) != 0) {
			_alpm_log(handle, ALPM_LOG_DEBUG,
					"%s: syntax error in description file line %d\n",
					newpkg->name ? newpkg->name : "error", linenum);
		} else {
			/* NULL the end of the key portion, move ptr to start of value */
			*ptr = '\0';
			ptr += 3;
			if(strcmp(key, "pkgname") == 0) {
				STRDUP(newpkg->name, ptr, return -1);
				newpkg->name_hash = _alpm_hash_sdbm(newpkg->name);
			} else if(strcmp(key, "pkgbase") == 0) {
				STRDUP(newpkg->base, ptr, return -1);
			} else if(strcmp(key, "pkgver") == 0) {
				STRDUP(newpkg->version, ptr, return -1);
			} else if(strcmp(key, "basever") == 0) {
				/* not used atm */
			} else if(strcmp(key, "pkgdesc") == 0) {
				STRDUP(newpkg->desc, ptr, return -1);
			} else if(strcmp(key, "group") == 0) {
				char *tmp = NULL;
				STRDUP(tmp, ptr, return -1);
				newpkg->groups = alpm_list_add(newpkg->groups, tmp);
			} else if(strcmp(key, "url") == 0) {
				STRDUP(newpkg->url, ptr, return -1);
			} else if(strcmp(key, "license") == 0) {
				char *tmp = NULL;
				STRDUP(tmp, ptr, return -1);
				newpkg->licenses = alpm_list_add(newpkg->licenses, tmp);
			} else if(strcmp(key, "builddate") == 0) {
				newpkg->builddate = _alpm_parsedate(ptr);
			} else if(strcmp(key, "packager") == 0) {
				STRDUP(newpkg->packager, ptr, return -1);
			} else if(strcmp(key, "arch") == 0) {
				STRDUP(newpkg->arch, ptr, return -1);
			} else if(strcmp(key, "size") == 0) {
				/* size in the raw package is uncompressed (installed) size */
				newpkg->isize = _alpm_strtoofft(ptr);
			} else if(strcmp(key, "depend") == 0) {
				alpm_depend_t *dep = alpm_dep_from_string(ptr);
				newpkg->depends = alpm_list_add(newpkg->depends, dep);
			} else if(strcmp(key, "optdepend") == 0) {
				alpm_depend_t *optdep = alpm_dep_from_string(ptr);
				newpkg->optdepends = alpm_list_add(newpkg->optdepends, optdep);
			} else if(strcmp(key, "makedepend") == 0) {
				alpm_depend_t *makedep = alpm_dep_from_string(ptr);
				newpkg->makedepends = alpm_list_add(newpkg->makedepends, makedep);
			} else if(strcmp(key, "checkdepend") == 0) {
				alpm_depend_t *checkdep = alpm_dep_from_string(ptr);
				newpkg->checkdepends = alpm_list_add(newpkg->checkdepends, checkdep);
			} else if(strcmp(key, "conflict") == 0) {
				alpm_depend_t *conflict = alpm_dep_from_string(ptr);
				newpkg->conflicts = alpm_list_add(newpkg->conflicts, conflict);
			} else if(strcmp(key, "replaces") == 0) {
				alpm_depend_t *replace = alpm_dep_from_string(ptr);
				newpkg->replaces = alpm_list_add(newpkg->replaces, replace);
			} else if(strcmp(key, "provides") == 0) {
				alpm_depend_t *provide = alpm_dep_from_string(ptr);
				newpkg->provides = alpm_list_add(newpkg->provides, provide);
			} else if(strcmp(key, "backup") == 0) {
				alpm_backup_t *backup;
				CALLOC(backup, 1, sizeof(alpm_backup_t), return -1);
				STRDUP(backup->name, ptr, FREE(backup); return -1);
				newpkg->backup = alpm_list_add(newpkg->backup, backup);
			} else if(strcmp(key, "force") == 0) {
				/* deprecated, skip it */
			} else if(strcmp(key, "makepkgopt") == 0) {
				/* not used atm */
			} else {
				_alpm_log(handle, ALPM_LOG_DEBUG, "%s: unknown key '%s' in description file line %d\n",
									newpkg->name ? newpkg->name : "error", key, linenum);
			}
		}
	}
	if(ret != ARCHIVE_EOF) {
		_alpm_log(handle, ALPM_LOG_DEBUG, "error parsing package descfile\n");
		return -1;
	}

	return 0;
}

/**
 * Validate a package.
 * @param handle the context handle
 * @param pkgfile path to the package file
 * @param syncpkg package object to load verification data from (md5sum,
 * sha256sum, and/or base64 signature)
 * @param level the required level of signature verification
 * @param sigdata signature data from the package to pass back
 * @param validation successful validations performed on the package file
 * @return 0 if package is fully valid, -1 and pm_errno otherwise
 */
int _alpm_pkg_validate_internal(alpm_handle_t *handle,
		const char *pkgfile, alpm_pkg_t *syncpkg, int level,
		alpm_siglist_t **sigdata, int *validation)
{
	int has_sig;
	handle->pm_errno = ALPM_ERR_OK;

	if(pkgfile == NULL || strlen(pkgfile) == 0) {
		RET_ERR(handle, ALPM_ERR_WRONG_ARGS, -1);
	}

	/* attempt to access the package file, ensure it exists */
	if(_alpm_access(handle, NULL, pkgfile, R_OK) != 0) {
		if(errno == ENOENT) {
			handle->pm_errno = ALPM_ERR_PKG_NOT_FOUND;
		} else if(errno == EACCES) {
			handle->pm_errno = ALPM_ERR_BADPERMS;
		} else {
			handle->pm_errno = ALPM_ERR_PKG_OPEN;
		}
		return -1;
	}

	/* can we get away with skipping checksums? */
	has_sig = 0;
	if(level & ALPM_SIG_PACKAGE) {
		if(syncpkg && syncpkg->base64_sig) {
			has_sig = 1;
		} else {
			char *sigpath = _alpm_sigpath(handle, pkgfile);
			if(sigpath && !_alpm_access(handle, NULL, sigpath, R_OK)) {
				has_sig = 1;
			}
			free(sigpath);
		}
	}

	if(syncpkg && (!has_sig || !syncpkg->base64_sig)) {
		if(syncpkg->md5sum && !syncpkg->sha256sum) {
			_alpm_log(handle, ALPM_LOG_DEBUG, "md5sum: %s\n", syncpkg->md5sum);
			_alpm_log(handle, ALPM_LOG_DEBUG, "checking md5sum for %s\n", pkgfile);
			if(_alpm_test_checksum(pkgfile, syncpkg->md5sum, ALPM_PKG_VALIDATION_MD5SUM) != 0) {
				RET_ERR(handle, ALPM_ERR_PKG_INVALID_CHECKSUM, -1);
			}
			if(validation) {
				*validation |= ALPM_PKG_VALIDATION_MD5SUM;
			}
		}

		if(syncpkg->sha256sum) {
			_alpm_log(handle, ALPM_LOG_DEBUG, "sha256sum: %s\n", syncpkg->sha256sum);
			_alpm_log(handle, ALPM_LOG_DEBUG, "checking sha256sum for %s\n", pkgfile);
			if(_alpm_test_checksum(pkgfile, syncpkg->sha256sum, ALPM_PKG_VALIDATION_SHA256SUM) != 0) {
				RET_ERR(handle, ALPM_ERR_PKG_INVALID_CHECKSUM, -1);
			}
			if(validation) {
				*validation |= ALPM_PKG_VALIDATION_SHA256SUM;
			}
		}
	}

	/* even if we don't have a sig, run the check code if level tells us to */
	if(level & ALPM_SIG_PACKAGE) {
		const char *sig = syncpkg ? syncpkg->base64_sig : NULL;
		_alpm_log(handle, ALPM_LOG_DEBUG, "sig data: %s\n", sig ? sig : "<from .sig>");
		if(!has_sig && !(level & ALPM_SIG_PACKAGE_OPTIONAL)) {
			handle->pm_errno = ALPM_ERR_PKG_MISSING_SIG;
			return -1;
		}
		if(_alpm_check_pgp_helper(handle, pkgfile, sig,
					level & ALPM_SIG_PACKAGE_OPTIONAL, level & ALPM_SIG_PACKAGE_MARGINAL_OK,
					level & ALPM_SIG_PACKAGE_UNKNOWN_OK, sigdata)) {
			handle->pm_errno = ALPM_ERR_PKG_INVALID_SIG;
			return -1;
		}
		if(validation && has_sig) {
			*validation |= ALPM_PKG_VALIDATION_SIGNATURE;
		}
	}

	if(validation && !*validation) {
		*validation = ALPM_PKG_VALIDATION_NONE;
	}

	return 0;
}

/**
 * Handle the existence of simple paths for _alpm_load_pkg_internal()
 * @param pkg package to change
 * @param path path to examine
 * @return 0 if path doesn't match any rule, 1 if it has been handled
 */
static int handle_simple_path(alpm_pkg_t *pkg, const char *path)
{
	if(strcmp(path, ".INSTALL") == 0) {
		pkg->scriptlet = 1;
		return 1;
	} else if(*path == '.') {
		/* for now, ignore all files starting with '.' that haven't
		 * already been handled (for future possibilities) */
		return 1;
	}

	return 0;
}

/**
 * Add a file to the files list for pkg.
 *
 * @param pkg package to add the file to
 * @param files_size size of pkg->files.files
 * @param entry archive entry of the file to add to the list
 * @param path path of the file to be added
 * @return <0 on error, 0 on success
 */
static int add_entry_to_files_list(alpm_filelist_t *filelist,
		size_t *files_size, struct archive_entry *entry, const char *path)
{
	const size_t files_count = filelist->count;
	alpm_file_t *current_file;
	mode_t type;
	size_t pathlen;

	if(!_alpm_greedy_grow((void **)&filelist->files,
				files_size, (files_count + 1) * sizeof(alpm_file_t))) {
		return -1;
	}

	type = archive_entry_filetype(entry);

	pathlen = strlen(path);

	current_file = filelist->files + files_count;

	/* mtree paths don't contain a tailing slash, those we get from
	 * the archive directly do (expensive way)
	 * Other code relies on it to detect directories so add it here.*/
	if(type == AE_IFDIR && path[pathlen - 1] != '/') {
		/* 2 = 1 for / + 1 for \0 */
		char *newpath;
		MALLOC(newpath, pathlen + 2, return -1);
		strcpy(newpath, path);
		newpath[pathlen] = '/';
		newpath[pathlen + 1] = '\0';
		current_file->name = newpath;
	} else {
		STRDUP(current_file->name, path, return -1);
	}
	current_file->size = archive_entry_size(entry);
	current_file->mode = archive_entry_mode(entry);
	filelist->count++;
	return 0;
}

/**
 * Generate a new file list from an mtree file and add it to the package.
 * An existing file list will be free()d first.
 *
 * archive should point to an archive struct which is already at the
 * position of the mtree's header.
 *
 * @param handle
 * @param pkg package to add the file list to
 * @param archive archive containing the mtree
 * @return 0 on success, <0 on error
 */
static int build_filelist_from_mtree(alpm_handle_t *handle, alpm_pkg_t *pkg, struct archive *archive)
{
	int ret = 0;
	size_t i;
	size_t mtree_maxsize = 0;
	size_t mtree_cursize = 0;
	size_t files_size = 0; /* we clean up the existing array so this is fine */
	char *mtree_data = NULL;
	struct archive *mtree;
	struct archive_entry *mtree_entry = NULL;
	alpm_filelist_t filelist = {0};

	_alpm_log(handle, ALPM_LOG_DEBUG,
			"found mtree for package %s, getting file list\n", pkg->filename);

	/* create a new archive to parse the mtree and load it from archive into memory */
	/* TODO: split this into a function */
	if((mtree = archive_read_new()) == NULL) {
		GOTO_ERR(handle, ALPM_ERR_LIBARCHIVE, error);
	}

	_alpm_archive_read_support_filter_all(mtree);
	archive_read_support_format_mtree(mtree);

	/* TODO: split this into a function */
	while(1) {
		ssize_t size;

		if(!_alpm_greedy_grow((void **)&mtree_data, &mtree_maxsize, mtree_cursize + ALPM_BUFFER_SIZE)) {
			goto error;
		}

		size = archive_read_data(archive, mtree_data + mtree_cursize, ALPM_BUFFER_SIZE);

		if(size < 0) {
			_alpm_log(handle, ALPM_LOG_DEBUG, _("error while reading package %s: %s\n"),
					pkg->filename, archive_error_string(archive));
			GOTO_ERR(handle, ALPM_ERR_LIBARCHIVE, error);
		}
		if(size == 0) {
			break;
		}

		mtree_cursize += size;
	}

	if(archive_read_open_memory(mtree, mtree_data, mtree_cursize)) {
		_alpm_log(handle, ALPM_LOG_DEBUG,
				_("error while reading mtree of package %s: %s\n"),
				pkg->filename, archive_error_string(mtree));
		GOTO_ERR(handle, ALPM_ERR_LIBARCHIVE, error);
	}

	while((ret = archive_read_next_header(mtree, &mtree_entry)) == ARCHIVE_OK) {
		const char *path = archive_entry_pathname(mtree_entry);

		/* strip leading "./" from path entries */
		if(path[0] == '.' && path[1] == '/') {
			path += 2;
		}

		if(handle_simple_path(pkg, path)) {
			continue;
		}

		if(add_entry_to_files_list(&filelist, &files_size, mtree_entry, path) < 0) {
			goto error;
		}
	}

	if(ret != ARCHIVE_EOF && ret != ARCHIVE_OK) { /* An error occurred */
		_alpm_log(handle, ALPM_LOG_DEBUG, _("error while reading mtree of package %s: %s\n"),
				pkg->filename, archive_error_string(mtree));
		GOTO_ERR(handle, ALPM_ERR_LIBARCHIVE, error);
	}

	/* throw away any files we loaded directly from the archive */
	for(i = 0; i < pkg->files.count; i++) {
		free(pkg->files.files[i].name);
	}
	free(pkg->files.files);

	/* copy over new filelist */
	memcpy(&pkg->files, &filelist, sizeof(alpm_filelist_t));

	free(mtree_data);
	_alpm_archive_read_free(mtree);
	_alpm_log(handle, ALPM_LOG_DEBUG, "finished mtree reading for %s\n", pkg->filename);
	return 0;
error:
	/* throw away any files we loaded from the mtree */
	for(i = 0; i < filelist.count; i++) {
		free(filelist.files[i].name);
	}
	free(filelist.files);

	free(mtree_data);
	_alpm_archive_read_free(mtree);
	return -1;
}

/**
 * Load a package and create the corresponding alpm_pkg_t struct.
 * @param handle the context handle
 * @param pkgfile path to the package file
 * @param full whether to stop the load after metadata is read or continue
 * through the full archive
 */
alpm_pkg_t *_alpm_pkg_load_internal(alpm_handle_t *handle,
		const char *pkgfile, int full)
{
	int ret, fd;
	int config = 0;
	int hit_mtree = 0;
	struct archive *archive;
	struct archive_entry *entry;
	alpm_pkg_t *newpkg;
	struct stat st;
	size_t files_size = 0;

	if(pkgfile == NULL || strlen(pkgfile) == 0) {
		RET_ERR(handle, ALPM_ERR_WRONG_ARGS, NULL);
	}

	fd = _alpm_open_archive(handle, pkgfile, &st, &archive, ALPM_ERR_PKG_OPEN);
	if(fd < 0) {
		if(errno == ENOENT) {
			handle->pm_errno = ALPM_ERR_PKG_NOT_FOUND;
		} else if(errno == EACCES) {
			handle->pm_errno = ALPM_ERR_BADPERMS;
		} else {
			handle->pm_errno = ALPM_ERR_PKG_OPEN;
		}
		return NULL;
	}

	newpkg = _alpm_pkg_new();
	if(newpkg == NULL) {
		GOTO_ERR(handle, ALPM_ERR_MEMORY, error);
	}
	STRDUP(newpkg->filename, pkgfile, GOTO_ERR(handle, ALPM_ERR_MEMORY, error));
	newpkg->size = st.st_size;

	_alpm_log(handle, ALPM_LOG_DEBUG, "starting package load for %s\n", pkgfile);

	/* If full is false, only read through the archive until we find our needed
	 * metadata. If it is true, read through the entire archive, which serves
	 * as a verification of integrity and allows us to create the filelist. */
	while((ret = archive_read_next_header(archive, &entry)) == ARCHIVE_OK) {
		const char *entry_name = archive_entry_pathname(entry);

		if(strcmp(entry_name, ".PKGINFO") == 0) {
			/* parse the info file */
			if(parse_descfile(handle, archive, newpkg) != 0) {
				_alpm_log(handle, ALPM_LOG_ERROR, _("could not parse package description file in %s\n"),
						pkgfile);
				goto pkg_invalid;
			}
			if(newpkg->name == NULL || strlen(newpkg->name) == 0) {
				_alpm_log(handle, ALPM_LOG_ERROR, _("missing package name in %s\n"), pkgfile);
				goto pkg_invalid;
			}
			if(newpkg->version == NULL || strlen(newpkg->version) == 0) {
				_alpm_log(handle, ALPM_LOG_ERROR, _("missing package version in %s\n"), pkgfile);
				goto pkg_invalid;
			}
			if(strchr(newpkg->version, '-') == NULL) {
				_alpm_log(handle, ALPM_LOG_ERROR, _("invalid package version in %s\n"), pkgfile);
				goto pkg_invalid;
			}
			config = 1;
			continue;
		} else if(full && strcmp(entry_name, ".MTREE") == 0) {
			/* building the file list: cheap way
			 * get the filelist from the mtree file rather than scanning
			 * the whole archive  */
			hit_mtree = build_filelist_from_mtree(handle, newpkg, archive) == 0;
			continue;
		} else if(handle_simple_path(newpkg, entry_name)) {
			continue;
		} else if(full && !hit_mtree) {
			/* building the file list: expensive way */
			if(add_entry_to_files_list(&newpkg->files, &files_size, entry, entry_name) < 0) {
				goto error;
			}
		}

		if(archive_read_data_skip(archive)) {
			_alpm_log(handle, ALPM_LOG_ERROR, _("error while reading package %s: %s\n"),
					pkgfile, archive_error_string(archive));
			GOTO_ERR(handle, ALPM_ERR_LIBARCHIVE, error);
		}

		/* if we are not doing a full read, see if we have all we need */
		if((!full || hit_mtree) && config) {
			break;
		}
	}

	if(ret != ARCHIVE_EOF && ret != ARCHIVE_OK) { /* An error occurred */
		_alpm_log(handle, ALPM_LOG_ERROR, _("error while reading package %s: %s\n"),
				pkgfile, archive_error_string(archive));
		GOTO_ERR(handle, ALPM_ERR_LIBARCHIVE, error);
	}

	if(!config) {
		_alpm_log(handle, ALPM_LOG_ERROR, _("missing package metadata in %s\n"), pkgfile);
		goto pkg_invalid;
	}

	_alpm_archive_read_free(archive);
	close(fd);

	/* internal fields for package struct */
	newpkg->origin = ALPM_PKG_FROM_FILE;
	STRDUP(newpkg->origin_data.file, pkgfile, goto error);
	newpkg->ops = get_file_pkg_ops();
	newpkg->handle = handle;
	newpkg->infolevel = INFRQ_BASE | INFRQ_DESC | INFRQ_SCRIPTLET;
	newpkg->validation = ALPM_PKG_VALIDATION_NONE;

	if(full) {
		if(newpkg->files.files) {
			/* attempt to hand back any memory we don't need */
			REALLOC(newpkg->files.files, sizeof(alpm_file_t) * newpkg->files.count, (void)0);
			/* "checking for conflicts" requires a sorted list, ensure that here */
			_alpm_log(handle, ALPM_LOG_DEBUG,
					"sorting package filelist for %s\n", pkgfile);

			_alpm_filelist_sort(&newpkg->files);
		}
		newpkg->infolevel |= INFRQ_FILES;
	}

	return newpkg;

pkg_invalid:
	handle->pm_errno = ALPM_ERR_PKG_INVALID;
error:
	_alpm_pkg_free(newpkg);
	_alpm_archive_read_free(archive);
	if(fd >= 0) {
		close(fd);
	}

	return NULL;
}

/* adopted limit from repo-add */
#define MAX_SIGFILE_SIZE 16384

static int read_sigfile(const char *sigpath, unsigned char **sig)
{
	struct stat st;
	FILE *fp;

	if((fp = fopen(sigpath, "rb")) == NULL) {
		return -1;
	}

	if(fstat(fileno(fp), &st) != 0 || st.st_size > MAX_SIGFILE_SIZE) {
		fclose(fp);
		return -1;
	}

	MALLOC(*sig, st.st_size, fclose(fp); return -1);

	if(fread(*sig, st.st_size, 1, fp) != 1) {
		free(*sig);
		fclose(fp);
		return -1;
	}

	fclose(fp);
	return st.st_size;
}

int SYMEXPORT alpm_pkg_load(alpm_handle_t *handle, const char *filename, int full,
		int level, alpm_pkg_t **pkg)
{
	int validation = 0;
	char *sigpath;
	alpm_pkg_t *pkg_temp;
	char *packager;

	CHECK_HANDLE(handle, return -1);
	ASSERT(pkg != NULL, RET_ERR(handle, ALPM_ERR_WRONG_ARGS, -1));

	sigpath = _alpm_sigpath(handle, filename);
	if(sigpath && !_alpm_access(handle, NULL, sigpath, R_OK)) {
		if(level & ALPM_SIG_PACKAGE) {
			alpm_list_t *keys = NULL;
			int fail = 0;
			unsigned char *sig = NULL;
			int len = read_sigfile(sigpath, &sig);

			if(len == -1) {
				_alpm_log(handle, ALPM_LOG_ERROR,
					_("failed to read signature file: %s\n"), sigpath);
				free(sigpath);
				return -1;
			}

			if(alpm_extract_keyid(handle, filename, sig, len, &keys) == 0) {
				alpm_list_t *k;
				for(k = keys; k; k = k->next) {
					char *key = k->data;
					if(_alpm_key_in_keychain(handle, key) == 0) {
						pkg_temp = _alpm_pkg_load_internal(handle, filename, full);
						if(pkg_temp) {
							packager = pkg_temp->packager;

						} else {
							packager = NULL;
						}
						if(_alpm_key_import(handle, packager, key) == -1) {
							fail = 1;
						}
						_alpm_pkg_free(pkg_temp);
					}
				}
				FREELIST(keys);
			}

			free(sig);

			if(fail) {
				_alpm_log(handle, ALPM_LOG_ERROR, _("required key missing from keyring\n"));
				free(sigpath);
				return -1;
			}
		}
	}
	free(sigpath);

	if(_alpm_pkg_validate_internal(handle, filename, NULL, level, NULL,
				&validation) == -1) {
		/* pm_errno is set by pkg_validate */
		return -1;
	}
	*pkg = _alpm_pkg_load_internal(handle, filename, full);
	if(*pkg == NULL) {
		/* pm_errno is set by pkg_load */
		return -1;
	}
	(*pkg)->validation = validation;

	return 0;
}