1 /*-
2 * Copyright (c) 2003-2007 Tim Kientzle
3 * Copyright (c) 2011-2012 Michihiro NAKAJIMA
4 * Copyright (c) 2016 Martin Matuska
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28 #include "archive_platform.h"
29 __FBSDID("$FreeBSD: head/lib/libarchive/archive_read_support_format_tar.c 201161 2009-12-29 05:44:39Z kientzle $");
30
31 #ifdef HAVE_ERRNO_H
32 #include <errno.h>
33 #endif
34 #include <stddef.h>
35 #ifdef HAVE_STDLIB_H
36 #include <stdlib.h>
37 #endif
38 #ifdef HAVE_STRING_H
39 #include <string.h>
40 #endif
41
42 #include "archive.h"
43 #include "archive_acl_private.h" /* For ACL parsing routines. */
44 #include "archive_entry.h"
45 #include "archive_entry_locale.h"
46 #include "archive_private.h"
47 #include "archive_read_private.h"
48
49 #define tar_min(a,b) ((a) < (b) ? (a) : (b))
50
51 /*
52 * Layout of POSIX 'ustar' tar header.
53 */
54 struct archive_entry_header_ustar {
55 char name[100];
56 char mode[8];
57 char uid[8];
58 char gid[8];
59 char size[12];
60 char mtime[12];
61 char checksum[8];
62 char typeflag[1];
63 char linkname[100]; /* "old format" header ends here */
64 char magic[6]; /* For POSIX: "ustar\0" */
65 char version[2]; /* For POSIX: "00" */
66 char uname[32];
67 char gname[32];
68 char rdevmajor[8];
69 char rdevminor[8];
70 char prefix[155];
71 };
72
73 /*
74 * Structure of GNU tar header
75 */
76 struct gnu_sparse {
77 char offset[12];
78 char numbytes[12];
79 };
80
81 struct archive_entry_header_gnutar {
82 char name[100];
83 char mode[8];
84 char uid[8];
85 char gid[8];
86 char size[12];
87 char mtime[12];
88 char checksum[8];
89 char typeflag[1];
90 char linkname[100];
91 char magic[8]; /* "ustar \0" (note blank/blank/null at end) */
92 char uname[32];
93 char gname[32];
94 char rdevmajor[8];
95 char rdevminor[8];
96 char atime[12];
97 char ctime[12];
98 char offset[12];
99 char longnames[4];
100 char unused[1];
101 struct gnu_sparse sparse[4];
102 char isextended[1];
103 char realsize[12];
104 /*
105 * Old GNU format doesn't use POSIX 'prefix' field; they use
106 * the 'L' (longname) entry instead.
107 */
108 };
109
110 /*
111 * Data specific to this format.
112 */
113 struct sparse_block {
114 struct sparse_block *next;
115 int64_t offset;
116 int64_t remaining;
117 int hole;
118 };
119
120 struct tar {
121 struct archive_string acl_text;
122 struct archive_string entry_pathname;
123 /* For "GNU.sparse.name" and other similar path extensions. */
124 struct archive_string entry_pathname_override;
125 struct archive_string entry_linkpath;
126 struct archive_string entry_uname;
127 struct archive_string entry_gname;
128 struct archive_string longlink;
129 struct archive_string longname;
130 struct archive_string pax_header;
131 struct archive_string pax_global;
132 struct archive_string line;
133 int pax_hdrcharset_binary;
134 int header_recursion_depth;
135 int64_t entry_bytes_remaining;
136 int64_t entry_offset;
137 int64_t entry_padding;
138 int64_t entry_bytes_unconsumed;
139 int64_t realsize;
140 int sparse_allowed;
141 struct sparse_block *sparse_list;
142 struct sparse_block *sparse_last;
143 int64_t sparse_offset;
144 int64_t sparse_numbytes;
145 int sparse_gnu_major;
146 int sparse_gnu_minor;
147 char sparse_gnu_pending;
148
149 struct archive_string localname;
150 struct archive_string_conv *opt_sconv;
151 struct archive_string_conv *sconv;
152 struct archive_string_conv *sconv_acl;
153 struct archive_string_conv *sconv_default;
154 int init_default_conversion;
155 int compat_2x;
156 int process_mac_extensions;
157 int read_concatenated_archives;
158 int realsize_override;
159 };
160
161 static int archive_block_is_null(const char *p);
162 static char *base64_decode(const char *, size_t, size_t *);
163 static int gnu_add_sparse_entry(struct archive_read *, struct tar *,
164 int64_t offset, int64_t remaining);
165
166 static void gnu_clear_sparse_list(struct tar *);
167 static int gnu_sparse_old_read(struct archive_read *, struct tar *,
168 const struct archive_entry_header_gnutar *header, size_t *);
169 static int gnu_sparse_old_parse(struct archive_read *, struct tar *,
170 const struct gnu_sparse *sparse, int length);
171 static int gnu_sparse_01_parse(struct archive_read *, struct tar *,
172 const char *);
173 static ssize_t gnu_sparse_10_read(struct archive_read *, struct tar *,
174 size_t *);
175 static int header_Solaris_ACL(struct archive_read *, struct tar *,
176 struct archive_entry *, const void *, size_t *);
177 static int header_common(struct archive_read *, struct tar *,
178 struct archive_entry *, const void *);
179 static int header_old_tar(struct archive_read *, struct tar *,
180 struct archive_entry *, const void *);
181 static int header_pax_extensions(struct archive_read *, struct tar *,
182 struct archive_entry *, const void *, size_t *);
183 static int header_pax_global(struct archive_read *, struct tar *,
184 struct archive_entry *, const void *h, size_t *);
185 static int header_longlink(struct archive_read *, struct tar *,
186 struct archive_entry *, const void *h, size_t *);
187 static int header_longname(struct archive_read *, struct tar *,
188 struct archive_entry *, const void *h, size_t *);
189 static int read_mac_metadata_blob(struct archive_read *, struct tar *,
190 struct archive_entry *, const void *h, size_t *);
191 static int header_volume(struct archive_read *, struct tar *,
192 struct archive_entry *, const void *h, size_t *);
193 static int header_ustar(struct archive_read *, struct tar *,
194 struct archive_entry *, const void *h);
195 static int header_gnutar(struct archive_read *, struct tar *,
196 struct archive_entry *, const void *h, size_t *);
197 static int archive_read_format_tar_bid(struct archive_read *, int);
198 static int archive_read_format_tar_options(struct archive_read *,
199 const char *, const char *);
200 static int archive_read_format_tar_cleanup(struct archive_read *);
201 static int archive_read_format_tar_read_data(struct archive_read *a,
202 const void **buff, size_t *size, int64_t *offset);
203 static int archive_read_format_tar_skip(struct archive_read *a);
204 static int archive_read_format_tar_read_header(struct archive_read *,
205 struct archive_entry *);
206 static int checksum(struct archive_read *, const void *);
207 static int pax_attribute(struct archive_read *, struct tar *,
208 struct archive_entry *, const char *key, const char *value,
209 size_t value_length);
210 static int pax_attribute_acl(struct archive_read *, struct tar *,
211 struct archive_entry *, const char *, int);
212 static int pax_attribute_xattr(struct archive_entry *, const char *,
213 const char *);
214 static int pax_header(struct archive_read *, struct tar *,
215 struct archive_entry *, struct archive_string *);
216 static void pax_time(const char *, int64_t *sec, long *nanos);
217 static ssize_t readline(struct archive_read *, struct tar *, const char **,
218 ssize_t limit, size_t *);
219 static int read_body_to_string(struct archive_read *, struct tar *,
220 struct archive_string *, const void *h, size_t *);
221 static int solaris_sparse_parse(struct archive_read *, struct tar *,
222 struct archive_entry *, const char *);
223 static int64_t tar_atol(const char *, size_t);
224 static int64_t tar_atol10(const char *, size_t);
225 static int64_t tar_atol256(const char *, size_t);
226 static int64_t tar_atol8(const char *, size_t);
227 static int tar_read_header(struct archive_read *, struct tar *,
228 struct archive_entry *, size_t *);
229 static int tohex(int c);
230 static char *url_decode(const char *);
231 static void tar_flush_unconsumed(struct archive_read *, size_t *);
232
233
234 int
archive_read_support_format_gnutar(struct archive * a)235 archive_read_support_format_gnutar(struct archive *a)
236 {
237 archive_check_magic(a, ARCHIVE_READ_MAGIC,
238 ARCHIVE_STATE_NEW, "archive_read_support_format_gnutar");
239 return (archive_read_support_format_tar(a));
240 }
241
242
243 int
archive_read_support_format_tar(struct archive * _a)244 archive_read_support_format_tar(struct archive *_a)
245 {
246 struct archive_read *a = (struct archive_read *)_a;
247 struct tar *tar;
248 int r;
249
250 archive_check_magic(_a, ARCHIVE_READ_MAGIC,
251 ARCHIVE_STATE_NEW, "archive_read_support_format_tar");
252
253 tar = (struct tar *)calloc(1, sizeof(*tar));
254 if (tar == NULL) {
255 archive_set_error(&a->archive, ENOMEM,
256 "Can't allocate tar data");
257 return (ARCHIVE_FATAL);
258 }
259 #ifdef HAVE_COPYFILE_H
260 /* Set this by default on Mac OS. */
261 tar->process_mac_extensions = 1;
262 #endif
263
264 r = __archive_read_register_format(a, tar, "tar",
265 archive_read_format_tar_bid,
266 archive_read_format_tar_options,
267 archive_read_format_tar_read_header,
268 archive_read_format_tar_read_data,
269 archive_read_format_tar_skip,
270 NULL,
271 archive_read_format_tar_cleanup,
272 NULL,
273 NULL);
274
275 if (r != ARCHIVE_OK)
276 free(tar);
277 return (ARCHIVE_OK);
278 }
279
280 static int
archive_read_format_tar_cleanup(struct archive_read * a)281 archive_read_format_tar_cleanup(struct archive_read *a)
282 {
283 struct tar *tar;
284
285 tar = (struct tar *)(a->format->data);
286 gnu_clear_sparse_list(tar);
287 archive_string_free(&tar->acl_text);
288 archive_string_free(&tar->entry_pathname);
289 archive_string_free(&tar->entry_pathname_override);
290 archive_string_free(&tar->entry_linkpath);
291 archive_string_free(&tar->entry_uname);
292 archive_string_free(&tar->entry_gname);
293 archive_string_free(&tar->line);
294 archive_string_free(&tar->pax_global);
295 archive_string_free(&tar->pax_header);
296 archive_string_free(&tar->longname);
297 archive_string_free(&tar->longlink);
298 archive_string_free(&tar->localname);
299 free(tar);
300 (a->format->data) = NULL;
301 return (ARCHIVE_OK);
302 }
303
304 /*
305 * Validate number field
306 *
307 * This has to be pretty lenient in order to accommodate the enormous
308 * variety of tar writers in the world:
309 * = POSIX (IEEE Std 1003.1-1988) ustar requires octal values with leading
310 * zeros and allows fields to be terminated with space or null characters
311 * = Many writers use different termination (in particular, libarchive
312 * omits terminator bytes to squeeze one or two more digits)
313 * = Many writers pad with space and omit leading zeros
314 * = GNU tar and star write base-256 values if numbers are too
315 * big to be represented in octal
316 *
317 * Examples of specific tar headers that we should support:
318 * = Perl Archive::Tar terminates uid, gid, devminor and devmajor with two
319 * null bytes, pads size with spaces and other numeric fields with zeroes
320 * = plexus-archiver prior to 2.6.3 (before switching to commons-compress)
321 * may have uid and gid fields filled with spaces without any octal digits
322 * at all and pads all numeric fields with spaces
323 *
324 * This should tolerate all variants in use. It will reject a field
325 * where the writer just left garbage after a trailing NUL.
326 */
327 static int
validate_number_field(const char * p_field,size_t i_size)328 validate_number_field(const char* p_field, size_t i_size)
329 {
330 unsigned char marker = (unsigned char)p_field[0];
331 if (marker == 128 || marker == 255 || marker == 0) {
332 /* Base-256 marker, there's nothing we can check. */
333 return 1;
334 } else {
335 /* Must be octal */
336 size_t i = 0;
337 /* Skip any leading spaces */
338 while (i < i_size && p_field[i] == ' ') {
339 ++i;
340 }
341 /* Skip octal digits. */
342 while (i < i_size && p_field[i] >= '0' && p_field[i] <= '7') {
343 ++i;
344 }
345 /* Any remaining characters must be space or NUL padding. */
346 while (i < i_size) {
347 if (p_field[i] != ' ' && p_field[i] != 0) {
348 return 0;
349 }
350 ++i;
351 }
352 return 1;
353 }
354 }
355
356 static int
archive_read_format_tar_bid(struct archive_read * a,int best_bid)357 archive_read_format_tar_bid(struct archive_read *a, int best_bid)
358 {
359 int bid;
360 const char *h;
361 const struct archive_entry_header_ustar *header;
362
363 (void)best_bid; /* UNUSED */
364
365 bid = 0;
366
367 /* Now let's look at the actual header and see if it matches. */
368 h = __archive_read_ahead(a, 512, NULL);
369 if (h == NULL)
370 return (-1);
371
372 /* If it's an end-of-archive mark, we can handle it. */
373 if (h[0] == 0 && archive_block_is_null(h)) {
374 /*
375 * Usually, I bid the number of bits verified, but
376 * in this case, 4096 seems excessive so I picked 10 as
377 * an arbitrary but reasonable-seeming value.
378 */
379 return (10);
380 }
381
382 /* If it's not an end-of-archive mark, it must have a valid checksum.*/
383 if (!checksum(a, h))
384 return (0);
385 bid += 48; /* Checksum is usually 6 octal digits. */
386
387 header = (const struct archive_entry_header_ustar *)h;
388
389 /* Recognize POSIX formats. */
390 if ((memcmp(header->magic, "ustar\0", 6) == 0)
391 && (memcmp(header->version, "00", 2) == 0))
392 bid += 56;
393
394 /* Recognize GNU tar format. */
395 if ((memcmp(header->magic, "ustar ", 6) == 0)
396 && (memcmp(header->version, " \0", 2) == 0))
397 bid += 56;
398
399 /* Type flag must be null, digit or A-Z, a-z. */
400 if (header->typeflag[0] != 0 &&
401 !( header->typeflag[0] >= '0' && header->typeflag[0] <= '9') &&
402 !( header->typeflag[0] >= 'A' && header->typeflag[0] <= 'Z') &&
403 !( header->typeflag[0] >= 'a' && header->typeflag[0] <= 'z') )
404 return (0);
405 bid += 2; /* 6 bits of variation in an 8-bit field leaves 2 bits. */
406
407 /*
408 * Check format of mode/uid/gid/mtime/size/rdevmajor/rdevminor fields.
409 */
410 if (bid > 0 && (
411 validate_number_field(header->mode, sizeof(header->mode)) == 0
412 || validate_number_field(header->uid, sizeof(header->uid)) == 0
413 || validate_number_field(header->gid, sizeof(header->gid)) == 0
414 || validate_number_field(header->mtime, sizeof(header->mtime)) == 0
415 || validate_number_field(header->size, sizeof(header->size)) == 0
416 || validate_number_field(header->rdevmajor, sizeof(header->rdevmajor)) == 0
417 || validate_number_field(header->rdevminor, sizeof(header->rdevminor)) == 0)) {
418 bid = 0;
419 }
420
421 return (bid);
422 }
423
424 static int
archive_read_format_tar_options(struct archive_read * a,const char * key,const char * val)425 archive_read_format_tar_options(struct archive_read *a,
426 const char *key, const char *val)
427 {
428 struct tar *tar;
429 int ret = ARCHIVE_FAILED;
430
431 tar = (struct tar *)(a->format->data);
432 if (strcmp(key, "compat-2x") == 0) {
433 /* Handle UTF-8 filenames as libarchive 2.x */
434 tar->compat_2x = (val != NULL && val[0] != 0);
435 tar->init_default_conversion = tar->compat_2x;
436 return (ARCHIVE_OK);
437 } else if (strcmp(key, "hdrcharset") == 0) {
438 if (val == NULL || val[0] == 0)
439 archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
440 "tar: hdrcharset option needs a character-set name");
441 else {
442 tar->opt_sconv =
443 archive_string_conversion_from_charset(
444 &a->archive, val, 0);
445 if (tar->opt_sconv != NULL)
446 ret = ARCHIVE_OK;
447 else
448 ret = ARCHIVE_FATAL;
449 }
450 return (ret);
451 } else if (strcmp(key, "mac-ext") == 0) {
452 tar->process_mac_extensions = (val != NULL && val[0] != 0);
453 return (ARCHIVE_OK);
454 } else if (strcmp(key, "read_concatenated_archives") == 0) {
455 tar->read_concatenated_archives = (val != NULL && val[0] != 0);
456 return (ARCHIVE_OK);
457 }
458
459 /* Note: The "warn" return is just to inform the options
460 * supervisor that we didn't handle it. It will generate
461 * a suitable error if no one used this option. */
462 return (ARCHIVE_WARN);
463 }
464
465 /* utility function- this exists to centralize the logic of tracking
466 * how much unconsumed data we have floating around, and to consume
467 * anything outstanding since we're going to do read_aheads
468 */
469 static void
tar_flush_unconsumed(struct archive_read * a,size_t * unconsumed)470 tar_flush_unconsumed(struct archive_read *a, size_t *unconsumed)
471 {
472 if (*unconsumed) {
473 /*
474 void *data = (void *)__archive_read_ahead(a, *unconsumed, NULL);
475 * this block of code is to poison claimed unconsumed space, ensuring
476 * things break if it is in use still.
477 * currently it WILL break things, so enable it only for debugging this issue
478 if (data) {
479 memset(data, 0xff, *unconsumed);
480 }
481 */
482 __archive_read_consume(a, *unconsumed);
483 *unconsumed = 0;
484 }
485 }
486
487 /*
488 * The function invoked by archive_read_next_header(). This
489 * just sets up a few things and then calls the internal
490 * tar_read_header() function below.
491 */
492 static int
archive_read_format_tar_read_header(struct archive_read * a,struct archive_entry * entry)493 archive_read_format_tar_read_header(struct archive_read *a,
494 struct archive_entry *entry)
495 {
496 /*
497 * When converting tar archives to cpio archives, it is
498 * essential that each distinct file have a distinct inode
499 * number. To simplify this, we keep a static count here to
500 * assign fake dev/inode numbers to each tar entry. Note that
501 * pax format archives may overwrite this with something more
502 * useful.
503 *
504 * Ideally, we would track every file read from the archive so
505 * that we could assign the same dev/ino pair to hardlinks,
506 * but the memory required to store a complete lookup table is
507 * probably not worthwhile just to support the relatively
508 * obscure tar->cpio conversion case.
509 */
510 static int default_inode;
511 static int default_dev;
512 struct tar *tar;
513 const char *p;
514 const wchar_t *wp;
515 int r;
516 size_t l, unconsumed = 0;
517
518 /* Assign default device/inode values. */
519 archive_entry_set_dev(entry, 1 + default_dev); /* Don't use zero. */
520 archive_entry_set_ino(entry, ++default_inode); /* Don't use zero. */
521 /* Limit generated st_ino number to 16 bits. */
522 if (default_inode >= 0xffff) {
523 ++default_dev;
524 default_inode = 0;
525 }
526
527 tar = (struct tar *)(a->format->data);
528 tar->entry_offset = 0;
529 gnu_clear_sparse_list(tar);
530 tar->realsize = -1; /* Mark this as "unset" */
531 tar->realsize_override = 0;
532
533 /* Setup default string conversion. */
534 tar->sconv = tar->opt_sconv;
535 if (tar->sconv == NULL) {
536 if (!tar->init_default_conversion) {
537 tar->sconv_default =
538 archive_string_default_conversion_for_read(&(a->archive));
539 tar->init_default_conversion = 1;
540 }
541 tar->sconv = tar->sconv_default;
542 }
543
544 r = tar_read_header(a, tar, entry, &unconsumed);
545
546 tar_flush_unconsumed(a, &unconsumed);
547
548 /*
549 * "non-sparse" files are really just sparse files with
550 * a single block.
551 */
552 if (tar->sparse_list == NULL) {
553 if (gnu_add_sparse_entry(a, tar, 0, tar->entry_bytes_remaining)
554 != ARCHIVE_OK)
555 return (ARCHIVE_FATAL);
556 } else {
557 struct sparse_block *sb;
558
559 for (sb = tar->sparse_list; sb != NULL; sb = sb->next) {
560 if (!sb->hole)
561 archive_entry_sparse_add_entry(entry,
562 sb->offset, sb->remaining);
563 }
564 }
565
566 if (r == ARCHIVE_OK && archive_entry_filetype(entry) == AE_IFREG) {
567 /*
568 * "Regular" entry with trailing '/' is really
569 * directory: This is needed for certain old tar
570 * variants and even for some broken newer ones.
571 */
572 if ((wp = archive_entry_pathname_w(entry)) != NULL) {
573 l = wcslen(wp);
574 if (l > 0 && wp[l - 1] == L'/') {
575 archive_entry_set_filetype(entry, AE_IFDIR);
576 tar->entry_bytes_remaining = 0;
577 tar->entry_padding = 0;
578 }
579 } else if ((p = archive_entry_pathname(entry)) != NULL) {
580 l = strlen(p);
581 if (l > 0 && p[l - 1] == '/') {
582 archive_entry_set_filetype(entry, AE_IFDIR);
583 tar->entry_bytes_remaining = 0;
584 tar->entry_padding = 0;
585 }
586 }
587 }
588 return (r);
589 }
590
591 static int
archive_read_format_tar_read_data(struct archive_read * a,const void ** buff,size_t * size,int64_t * offset)592 archive_read_format_tar_read_data(struct archive_read *a,
593 const void **buff, size_t *size, int64_t *offset)
594 {
595 ssize_t bytes_read;
596 struct tar *tar;
597 struct sparse_block *p;
598
599 tar = (struct tar *)(a->format->data);
600
601 for (;;) {
602 /* Remove exhausted entries from sparse list. */
603 while (tar->sparse_list != NULL &&
604 tar->sparse_list->remaining == 0) {
605 p = tar->sparse_list;
606 tar->sparse_list = p->next;
607 free(p);
608 }
609
610 if (tar->entry_bytes_unconsumed) {
611 __archive_read_consume(a, tar->entry_bytes_unconsumed);
612 tar->entry_bytes_unconsumed = 0;
613 }
614
615 /* If we're at end of file, return EOF. */
616 if (tar->sparse_list == NULL ||
617 tar->entry_bytes_remaining == 0) {
618 if (__archive_read_consume(a, tar->entry_padding) < 0)
619 return (ARCHIVE_FATAL);
620 tar->entry_padding = 0;
621 *buff = NULL;
622 *size = 0;
623 *offset = tar->realsize;
624 return (ARCHIVE_EOF);
625 }
626
627 *buff = __archive_read_ahead(a, 1, &bytes_read);
628 if (bytes_read < 0)
629 return (ARCHIVE_FATAL);
630 if (*buff == NULL) {
631 archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
632 "Truncated tar archive");
633 return (ARCHIVE_FATAL);
634 }
635 if (bytes_read > tar->entry_bytes_remaining)
636 bytes_read = (ssize_t)tar->entry_bytes_remaining;
637 /* Don't read more than is available in the
638 * current sparse block. */
639 if (tar->sparse_list->remaining < bytes_read)
640 bytes_read = (ssize_t)tar->sparse_list->remaining;
641 *size = bytes_read;
642 *offset = tar->sparse_list->offset;
643 tar->sparse_list->remaining -= bytes_read;
644 tar->sparse_list->offset += bytes_read;
645 tar->entry_bytes_remaining -= bytes_read;
646 tar->entry_bytes_unconsumed = bytes_read;
647
648 if (!tar->sparse_list->hole)
649 return (ARCHIVE_OK);
650 /* Current is hole data and skip this. */
651 }
652 }
653
654 static int
archive_read_format_tar_skip(struct archive_read * a)655 archive_read_format_tar_skip(struct archive_read *a)
656 {
657 int64_t bytes_skipped;
658 int64_t request;
659 struct sparse_block *p;
660 struct tar* tar;
661
662 tar = (struct tar *)(a->format->data);
663
664 /* Do not consume the hole of a sparse file. */
665 request = 0;
666 for (p = tar->sparse_list; p != NULL; p = p->next) {
667 if (!p->hole) {
668 if (p->remaining >= INT64_MAX - request) {
669 return ARCHIVE_FATAL;
670 }
671 request += p->remaining;
672 }
673 }
674 if (request > tar->entry_bytes_remaining)
675 request = tar->entry_bytes_remaining;
676 request += tar->entry_padding + tar->entry_bytes_unconsumed;
677
678 bytes_skipped = __archive_read_consume(a, request);
679 if (bytes_skipped < 0)
680 return (ARCHIVE_FATAL);
681
682 tar->entry_bytes_remaining = 0;
683 tar->entry_bytes_unconsumed = 0;
684 tar->entry_padding = 0;
685
686 /* Free the sparse list. */
687 gnu_clear_sparse_list(tar);
688
689 return (ARCHIVE_OK);
690 }
691
692 /*
693 * This function recursively interprets all of the headers associated
694 * with a single entry.
695 */
696 static int
tar_read_header(struct archive_read * a,struct tar * tar,struct archive_entry * entry,size_t * unconsumed)697 tar_read_header(struct archive_read *a, struct tar *tar,
698 struct archive_entry *entry, size_t *unconsumed)
699 {
700 ssize_t bytes;
701 int err, eof_vol_header;
702 const char *h;
703 const struct archive_entry_header_ustar *header;
704 const struct archive_entry_header_gnutar *gnuheader;
705
706 eof_vol_header = 0;
707
708 /* Loop until we find a workable header record. */
709 for (;;) {
710 tar_flush_unconsumed(a, unconsumed);
711
712 /* Read 512-byte header record */
713 h = __archive_read_ahead(a, 512, &bytes);
714 if (bytes < 0)
715 return ((int)bytes);
716 if (bytes == 0) { /* EOF at a block boundary. */
717 /* Some writers do omit the block of nulls. <sigh> */
718 return (ARCHIVE_EOF);
719 }
720 if (bytes < 512) { /* Short block at EOF; this is bad. */
721 archive_set_error(&a->archive,
722 ARCHIVE_ERRNO_FILE_FORMAT,
723 "Truncated tar archive");
724 return (ARCHIVE_FATAL);
725 }
726 *unconsumed = 512;
727
728 /* Header is workable if it's not an end-of-archive mark. */
729 if (h[0] != 0 || !archive_block_is_null(h))
730 break;
731
732 /* Ensure format is set for archives with only null blocks. */
733 if (a->archive.archive_format_name == NULL) {
734 a->archive.archive_format = ARCHIVE_FORMAT_TAR;
735 a->archive.archive_format_name = "tar";
736 }
737
738 if (!tar->read_concatenated_archives) {
739 /* Try to consume a second all-null record, as well. */
740 tar_flush_unconsumed(a, unconsumed);
741 h = __archive_read_ahead(a, 512, NULL);
742 if (h != NULL && h[0] == 0 && archive_block_is_null(h))
743 __archive_read_consume(a, 512);
744 archive_clear_error(&a->archive);
745 return (ARCHIVE_EOF);
746 }
747
748 /*
749 * We're reading concatenated archives, ignore this block and
750 * loop to get the next.
751 */
752 }
753
754 /*
755 * Note: If the checksum fails and we return ARCHIVE_RETRY,
756 * then the client is likely to just retry. This is a very
757 * crude way to search for the next valid header!
758 *
759 * TODO: Improve this by implementing a real header scan.
760 */
761 if (!checksum(a, h)) {
762 tar_flush_unconsumed(a, unconsumed);
763 archive_set_error(&a->archive, EINVAL, "Damaged tar archive");
764 return (ARCHIVE_RETRY); /* Retryable: Invalid header */
765 }
766
767 if (++tar->header_recursion_depth > 32) {
768 tar_flush_unconsumed(a, unconsumed);
769 archive_set_error(&a->archive, EINVAL, "Too many special headers");
770 return (ARCHIVE_WARN);
771 }
772
773 /* Determine the format variant. */
774 header = (const struct archive_entry_header_ustar *)h;
775
776 switch(header->typeflag[0]) {
777 case 'A': /* Solaris tar ACL */
778 a->archive.archive_format = ARCHIVE_FORMAT_TAR_PAX_INTERCHANGE;
779 a->archive.archive_format_name = "Solaris tar";
780 err = header_Solaris_ACL(a, tar, entry, h, unconsumed);
781 break;
782 case 'g': /* POSIX-standard 'g' header. */
783 a->archive.archive_format = ARCHIVE_FORMAT_TAR_PAX_INTERCHANGE;
784 a->archive.archive_format_name = "POSIX pax interchange format";
785 err = header_pax_global(a, tar, entry, h, unconsumed);
786 if (err == ARCHIVE_EOF)
787 return (err);
788 break;
789 case 'K': /* Long link name (GNU tar, others) */
790 err = header_longlink(a, tar, entry, h, unconsumed);
791 break;
792 case 'L': /* Long filename (GNU tar, others) */
793 err = header_longname(a, tar, entry, h, unconsumed);
794 break;
795 case 'V': /* GNU volume header */
796 err = header_volume(a, tar, entry, h, unconsumed);
797 if (err == ARCHIVE_EOF)
798 eof_vol_header = 1;
799 break;
800 case 'X': /* Used by SUN tar; same as 'x'. */
801 a->archive.archive_format = ARCHIVE_FORMAT_TAR_PAX_INTERCHANGE;
802 a->archive.archive_format_name =
803 "POSIX pax interchange format (Sun variant)";
804 err = header_pax_extensions(a, tar, entry, h, unconsumed);
805 break;
806 case 'x': /* POSIX-standard 'x' header. */
807 a->archive.archive_format = ARCHIVE_FORMAT_TAR_PAX_INTERCHANGE;
808 a->archive.archive_format_name = "POSIX pax interchange format";
809 err = header_pax_extensions(a, tar, entry, h, unconsumed);
810 break;
811 default:
812 gnuheader = (const struct archive_entry_header_gnutar *)h;
813 if (memcmp(gnuheader->magic, "ustar \0", 8) == 0) {
814 a->archive.archive_format = ARCHIVE_FORMAT_TAR_GNUTAR;
815 a->archive.archive_format_name = "GNU tar format";
816 err = header_gnutar(a, tar, entry, h, unconsumed);
817 } else if (memcmp(header->magic, "ustar", 5) == 0) {
818 if (a->archive.archive_format != ARCHIVE_FORMAT_TAR_PAX_INTERCHANGE) {
819 a->archive.archive_format = ARCHIVE_FORMAT_TAR_USTAR;
820 a->archive.archive_format_name = "POSIX ustar format";
821 }
822 err = header_ustar(a, tar, entry, h);
823 } else {
824 a->archive.archive_format = ARCHIVE_FORMAT_TAR;
825 a->archive.archive_format_name = "tar (non-POSIX)";
826 err = header_old_tar(a, tar, entry, h);
827 }
828 }
829 if (err == ARCHIVE_FATAL)
830 return (err);
831
832 tar_flush_unconsumed(a, unconsumed);
833
834 h = NULL;
835 header = NULL;
836
837 --tar->header_recursion_depth;
838 /* Yuck. Apple's design here ends up storing long pathname
839 * extensions for both the AppleDouble extension entry and the
840 * regular entry.
841 */
842 if ((err == ARCHIVE_WARN || err == ARCHIVE_OK) &&
843 tar->header_recursion_depth == 0 &&
844 tar->process_mac_extensions) {
845 int err2 = read_mac_metadata_blob(a, tar, entry, h, unconsumed);
846 if (err2 < err)
847 err = err2;
848 }
849
850 /* We return warnings or success as-is. Anything else is fatal. */
851 if (err == ARCHIVE_WARN || err == ARCHIVE_OK) {
852 if (tar->sparse_gnu_pending) {
853 if (tar->sparse_gnu_major == 1 &&
854 tar->sparse_gnu_minor == 0) {
855 ssize_t bytes_read;
856
857 tar->sparse_gnu_pending = 0;
858 /* Read initial sparse map. */
859 bytes_read = gnu_sparse_10_read(a, tar, unconsumed);
860 if (bytes_read < 0)
861 return ((int)bytes_read);
862 tar->entry_bytes_remaining -= bytes_read;
863 } else {
864 archive_set_error(&a->archive,
865 ARCHIVE_ERRNO_MISC,
866 "Unrecognized GNU sparse file format");
867 return (ARCHIVE_WARN);
868 }
869 tar->sparse_gnu_pending = 0;
870 }
871 return (err);
872 }
873 if (err == ARCHIVE_EOF) {
874 if (!eof_vol_header) {
875 /* EOF when recursively reading a header is bad. */
876 archive_set_error(&a->archive, EINVAL,
877 "Damaged tar archive");
878 } else {
879 /* If we encounter just a GNU volume header treat
880 * this situation as an empty archive */
881 return (ARCHIVE_EOF);
882 }
883 }
884 return (ARCHIVE_FATAL);
885 }
886
887 /*
888 * Return true if block checksum is correct.
889 */
890 static int
checksum(struct archive_read * a,const void * h)891 checksum(struct archive_read *a, const void *h)
892 {
893 const unsigned char *bytes;
894 const struct archive_entry_header_ustar *header;
895 int check, sum;
896 size_t i;
897
898 (void)a; /* UNUSED */
899 bytes = (const unsigned char *)h;
900 header = (const struct archive_entry_header_ustar *)h;
901
902 /* Checksum field must hold an octal number */
903 for (i = 0; i < sizeof(header->checksum); ++i) {
904 char c = header->checksum[i];
905 if (c != ' ' && c != '\0' && (c < '0' || c > '7'))
906 return 0;
907 }
908
909 /*
910 * Test the checksum. Note that POSIX specifies _unsigned_
911 * bytes for this calculation.
912 */
913 sum = (int)tar_atol(header->checksum, sizeof(header->checksum));
914 check = 0;
915 for (i = 0; i < 148; i++)
916 check += (unsigned char)bytes[i];
917 for (; i < 156; i++)
918 check += 32;
919 for (; i < 512; i++)
920 check += (unsigned char)bytes[i];
921 if (sum == check)
922 return (1);
923
924 /*
925 * Repeat test with _signed_ bytes, just in case this archive
926 * was created by an old BSD, Solaris, or HP-UX tar with a
927 * broken checksum calculation.
928 */
929 check = 0;
930 for (i = 0; i < 148; i++)
931 check += (signed char)bytes[i];
932 for (; i < 156; i++)
933 check += 32;
934 for (; i < 512; i++)
935 check += (signed char)bytes[i];
936 if (sum == check)
937 return (1);
938
939 return (0);
940 }
941
942 /*
943 * Return true if this block contains only nulls.
944 */
945 static int
archive_block_is_null(const char * p)946 archive_block_is_null(const char *p)
947 {
948 unsigned i;
949
950 for (i = 0; i < 512; i++)
951 if (*p++)
952 return (0);
953 return (1);
954 }
955
956 /*
957 * Interpret 'A' Solaris ACL header
958 */
959 static int
header_Solaris_ACL(struct archive_read * a,struct tar * tar,struct archive_entry * entry,const void * h,size_t * unconsumed)960 header_Solaris_ACL(struct archive_read *a, struct tar *tar,
961 struct archive_entry *entry, const void *h, size_t *unconsumed)
962 {
963 const struct archive_entry_header_ustar *header;
964 size_t size;
965 int err, acl_type;
966 int64_t type;
967 char *acl, *p;
968
969 /*
970 * read_body_to_string adds a NUL terminator, but we need a little
971 * more to make sure that we don't overrun acl_text later.
972 */
973 header = (const struct archive_entry_header_ustar *)h;
974 size = (size_t)tar_atol(header->size, sizeof(header->size));
975 err = read_body_to_string(a, tar, &(tar->acl_text), h, unconsumed);
976 if (err != ARCHIVE_OK)
977 return (err);
978
979 /* Recursively read next header */
980 err = tar_read_header(a, tar, entry, unconsumed);
981 if ((err != ARCHIVE_OK) && (err != ARCHIVE_WARN))
982 return (err);
983
984 /* TODO: Examine the first characters to see if this
985 * is an AIX ACL descriptor. We'll likely never support
986 * them, but it would be polite to recognize and warn when
987 * we do see them. */
988
989 /* Leading octal number indicates ACL type and number of entries. */
990 p = acl = tar->acl_text.s;
991 type = 0;
992 while (*p != '\0' && p < acl + size) {
993 if (*p < '0' || *p > '7') {
994 archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
995 "Malformed Solaris ACL attribute (invalid digit)");
996 return(ARCHIVE_WARN);
997 }
998 type <<= 3;
999 type += *p - '0';
1000 if (type > 077777777) {
1001 archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1002 "Malformed Solaris ACL attribute (count too large)");
1003 return (ARCHIVE_WARN);
1004 }
1005 p++;
1006 }
1007 switch ((int)type & ~0777777) {
1008 case 01000000:
1009 /* POSIX.1e ACL */
1010 acl_type = ARCHIVE_ENTRY_ACL_TYPE_ACCESS;
1011 break;
1012 case 03000000:
1013 /* NFSv4 ACL */
1014 acl_type = ARCHIVE_ENTRY_ACL_TYPE_NFS4;
1015 break;
1016 default:
1017 archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1018 "Malformed Solaris ACL attribute (unsupported type %o)",
1019 (int)type);
1020 return (ARCHIVE_WARN);
1021 }
1022 p++;
1023
1024 if (p >= acl + size) {
1025 archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1026 "Malformed Solaris ACL attribute (body overflow)");
1027 return(ARCHIVE_WARN);
1028 }
1029
1030 /* ACL text is null-terminated; find the end. */
1031 size -= (p - acl);
1032 acl = p;
1033
1034 while (*p != '\0' && p < acl + size)
1035 p++;
1036
1037 if (tar->sconv_acl == NULL) {
1038 tar->sconv_acl = archive_string_conversion_from_charset(
1039 &(a->archive), "UTF-8", 1);
1040 if (tar->sconv_acl == NULL)
1041 return (ARCHIVE_FATAL);
1042 }
1043 archive_strncpy(&(tar->localname), acl, p - acl);
1044 err = archive_acl_from_text_l(archive_entry_acl(entry),
1045 tar->localname.s, acl_type, tar->sconv_acl);
1046 if (err != ARCHIVE_OK) {
1047 if (errno == ENOMEM) {
1048 archive_set_error(&a->archive, ENOMEM,
1049 "Can't allocate memory for ACL");
1050 } else
1051 archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1052 "Malformed Solaris ACL attribute (unparsable)");
1053 }
1054 return (err);
1055 }
1056
1057 /*
1058 * Interpret 'K' long linkname header.
1059 */
1060 static int
header_longlink(struct archive_read * a,struct tar * tar,struct archive_entry * entry,const void * h,size_t * unconsumed)1061 header_longlink(struct archive_read *a, struct tar *tar,
1062 struct archive_entry *entry, const void *h, size_t *unconsumed)
1063 {
1064 int err;
1065
1066 err = read_body_to_string(a, tar, &(tar->longlink), h, unconsumed);
1067 if (err != ARCHIVE_OK)
1068 return (err);
1069 err = tar_read_header(a, tar, entry, unconsumed);
1070 if ((err != ARCHIVE_OK) && (err != ARCHIVE_WARN))
1071 return (err);
1072 /* Set symlink if symlink already set, else hardlink. */
1073 archive_entry_copy_link(entry, tar->longlink.s);
1074 return (ARCHIVE_OK);
1075 }
1076
1077 static int
set_conversion_failed_error(struct archive_read * a,struct archive_string_conv * sconv,const char * name)1078 set_conversion_failed_error(struct archive_read *a,
1079 struct archive_string_conv *sconv, const char *name)
1080 {
1081 if (errno == ENOMEM) {
1082 archive_set_error(&a->archive, ENOMEM,
1083 "Can't allocate memory for %s", name);
1084 return (ARCHIVE_FATAL);
1085 }
1086 archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
1087 "%s can't be converted from %s to current locale.",
1088 name, archive_string_conversion_charset_name(sconv));
1089 return (ARCHIVE_WARN);
1090 }
1091
1092 /*
1093 * Interpret 'L' long filename header.
1094 */
1095 static int
header_longname(struct archive_read * a,struct tar * tar,struct archive_entry * entry,const void * h,size_t * unconsumed)1096 header_longname(struct archive_read *a, struct tar *tar,
1097 struct archive_entry *entry, const void *h, size_t *unconsumed)
1098 {
1099 int err;
1100
1101 err = read_body_to_string(a, tar, &(tar->longname), h, unconsumed);
1102 if (err != ARCHIVE_OK)
1103 return (err);
1104 /* Read and parse "real" header, then override name. */
1105 err = tar_read_header(a, tar, entry, unconsumed);
1106 if ((err != ARCHIVE_OK) && (err != ARCHIVE_WARN))
1107 return (err);
1108 if (archive_entry_copy_pathname_l(entry, tar->longname.s,
1109 archive_strlen(&(tar->longname)), tar->sconv) != 0)
1110 err = set_conversion_failed_error(a, tar->sconv, "Pathname");
1111 return (err);
1112 }
1113
1114
1115 /*
1116 * Interpret 'V' GNU tar volume header.
1117 */
1118 static int
header_volume(struct archive_read * a,struct tar * tar,struct archive_entry * entry,const void * h,size_t * unconsumed)1119 header_volume(struct archive_read *a, struct tar *tar,
1120 struct archive_entry *entry, const void *h, size_t *unconsumed)
1121 {
1122 (void)h;
1123
1124 /* Just skip this and read the next header. */
1125 return (tar_read_header(a, tar, entry, unconsumed));
1126 }
1127
1128 /*
1129 * Read body of an archive entry into an archive_string object.
1130 */
1131 static int
read_body_to_string(struct archive_read * a,struct tar * tar,struct archive_string * as,const void * h,size_t * unconsumed)1132 read_body_to_string(struct archive_read *a, struct tar *tar,
1133 struct archive_string *as, const void *h, size_t *unconsumed)
1134 {
1135 int64_t size;
1136 const struct archive_entry_header_ustar *header;
1137 const void *src;
1138
1139 (void)tar; /* UNUSED */
1140 header = (const struct archive_entry_header_ustar *)h;
1141 size = tar_atol(header->size, sizeof(header->size));
1142 if ((size > 1048576) || (size < 0)) {
1143 archive_set_error(&a->archive, EINVAL,
1144 "Special header too large");
1145 return (ARCHIVE_FATAL);
1146 }
1147
1148 /* Fail if we can't make our buffer big enough. */
1149 if (archive_string_ensure(as, (size_t)size+1) == NULL) {
1150 archive_set_error(&a->archive, ENOMEM,
1151 "No memory");
1152 return (ARCHIVE_FATAL);
1153 }
1154
1155 tar_flush_unconsumed(a, unconsumed);
1156
1157 /* Read the body into the string. */
1158 *unconsumed = (size_t)((size + 511) & ~ 511);
1159 src = __archive_read_ahead(a, *unconsumed, NULL);
1160 if (src == NULL) {
1161 *unconsumed = 0;
1162 return (ARCHIVE_FATAL);
1163 }
1164 memcpy(as->s, src, (size_t)size);
1165 as->s[size] = '\0';
1166 as->length = (size_t)size;
1167 return (ARCHIVE_OK);
1168 }
1169
1170 /*
1171 * Parse out common header elements.
1172 *
1173 * This would be the same as header_old_tar, except that the
1174 * filename is handled slightly differently for old and POSIX
1175 * entries (POSIX entries support a 'prefix'). This factoring
1176 * allows header_old_tar and header_ustar
1177 * to handle filenames differently, while still putting most of the
1178 * common parsing into one place.
1179 */
1180 static int
header_common(struct archive_read * a,struct tar * tar,struct archive_entry * entry,const void * h)1181 header_common(struct archive_read *a, struct tar *tar,
1182 struct archive_entry *entry, const void *h)
1183 {
1184 const struct archive_entry_header_ustar *header;
1185 char tartype;
1186 int err = ARCHIVE_OK;
1187
1188 header = (const struct archive_entry_header_ustar *)h;
1189 if (header->linkname[0])
1190 archive_strncpy(&(tar->entry_linkpath),
1191 header->linkname, sizeof(header->linkname));
1192 else
1193 archive_string_empty(&(tar->entry_linkpath));
1194
1195 /* Parse out the numeric fields (all are octal) */
1196 archive_entry_set_mode(entry,
1197 (mode_t)tar_atol(header->mode, sizeof(header->mode)));
1198 archive_entry_set_uid(entry, tar_atol(header->uid, sizeof(header->uid)));
1199 archive_entry_set_gid(entry, tar_atol(header->gid, sizeof(header->gid)));
1200 tar->entry_bytes_remaining = tar_atol(header->size, sizeof(header->size));
1201 if (tar->entry_bytes_remaining < 0) {
1202 tar->entry_bytes_remaining = 0;
1203 archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1204 "Tar entry has negative size");
1205 return (ARCHIVE_FATAL);
1206 }
1207 if (tar->entry_bytes_remaining == INT64_MAX) {
1208 /* Note: tar_atol returns INT64_MAX on overflow */
1209 tar->entry_bytes_remaining = 0;
1210 archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1211 "Tar entry size overflow");
1212 return (ARCHIVE_FATAL);
1213 }
1214 tar->realsize = tar->entry_bytes_remaining;
1215 archive_entry_set_size(entry, tar->entry_bytes_remaining);
1216 archive_entry_set_mtime(entry, tar_atol(header->mtime, sizeof(header->mtime)), 0);
1217
1218 /* Handle the tar type flag appropriately. */
1219 tartype = header->typeflag[0];
1220
1221 switch (tartype) {
1222 case '1': /* Hard link */
1223 if (archive_entry_copy_hardlink_l(entry, tar->entry_linkpath.s,
1224 archive_strlen(&(tar->entry_linkpath)), tar->sconv) != 0) {
1225 err = set_conversion_failed_error(a, tar->sconv,
1226 "Linkname");
1227 if (err == ARCHIVE_FATAL)
1228 return (err);
1229 }
1230 /*
1231 * The following may seem odd, but: Technically, tar
1232 * does not store the file type for a "hard link"
1233 * entry, only the fact that it is a hard link. So, I
1234 * leave the type zero normally. But, pax interchange
1235 * format allows hard links to have data, which
1236 * implies that the underlying entry is a regular
1237 * file.
1238 */
1239 if (archive_entry_size(entry) > 0)
1240 archive_entry_set_filetype(entry, AE_IFREG);
1241
1242 /*
1243 * A tricky point: Traditionally, tar readers have
1244 * ignored the size field when reading hardlink
1245 * entries, and some writers put non-zero sizes even
1246 * though the body is empty. POSIX blessed this
1247 * convention in the 1988 standard, but broke with
1248 * this tradition in 2001 by permitting hardlink
1249 * entries to store valid bodies in pax interchange
1250 * format, but not in ustar format. Since there is no
1251 * hard and fast way to distinguish pax interchange
1252 * from earlier archives (the 'x' and 'g' entries are
1253 * optional, after all), we need a heuristic.
1254 */
1255 if (archive_entry_size(entry) == 0) {
1256 /* If the size is already zero, we're done. */
1257 } else if (a->archive.archive_format
1258 == ARCHIVE_FORMAT_TAR_PAX_INTERCHANGE) {
1259 /* Definitely pax extended; must obey hardlink size. */
1260 } else if (a->archive.archive_format == ARCHIVE_FORMAT_TAR
1261 || a->archive.archive_format == ARCHIVE_FORMAT_TAR_GNUTAR)
1262 {
1263 /* Old-style or GNU tar: we must ignore the size. */
1264 archive_entry_set_size(entry, 0);
1265 tar->entry_bytes_remaining = 0;
1266 } else if (archive_read_format_tar_bid(a, 50) > 50) {
1267 /*
1268 * We don't know if it's pax: If the bid
1269 * function sees a valid ustar header
1270 * immediately following, then let's ignore
1271 * the hardlink size.
1272 */
1273 archive_entry_set_size(entry, 0);
1274 tar->entry_bytes_remaining = 0;
1275 }
1276 /*
1277 * TODO: There are still two cases I'd like to handle:
1278 * = a ustar non-pax archive with a hardlink entry at
1279 * end-of-archive. (Look for block of nulls following?)
1280 * = a pax archive that has not seen any pax headers
1281 * and has an entry which is a hardlink entry storing
1282 * a body containing an uncompressed tar archive.
1283 * The first is worth addressing; I don't see any reliable
1284 * way to deal with the second possibility.
1285 */
1286 break;
1287 case '2': /* Symlink */
1288 archive_entry_set_filetype(entry, AE_IFLNK);
1289 archive_entry_set_size(entry, 0);
1290 tar->entry_bytes_remaining = 0;
1291 if (archive_entry_copy_symlink_l(entry, tar->entry_linkpath.s,
1292 archive_strlen(&(tar->entry_linkpath)), tar->sconv) != 0) {
1293 err = set_conversion_failed_error(a, tar->sconv,
1294 "Linkname");
1295 if (err == ARCHIVE_FATAL)
1296 return (err);
1297 }
1298 break;
1299 case '3': /* Character device */
1300 archive_entry_set_filetype(entry, AE_IFCHR);
1301 archive_entry_set_size(entry, 0);
1302 tar->entry_bytes_remaining = 0;
1303 break;
1304 case '4': /* Block device */
1305 archive_entry_set_filetype(entry, AE_IFBLK);
1306 archive_entry_set_size(entry, 0);
1307 tar->entry_bytes_remaining = 0;
1308 break;
1309 case '5': /* Dir */
1310 archive_entry_set_filetype(entry, AE_IFDIR);
1311 archive_entry_set_size(entry, 0);
1312 tar->entry_bytes_remaining = 0;
1313 break;
1314 case '6': /* FIFO device */
1315 archive_entry_set_filetype(entry, AE_IFIFO);
1316 archive_entry_set_size(entry, 0);
1317 tar->entry_bytes_remaining = 0;
1318 break;
1319 case 'D': /* GNU incremental directory type */
1320 /*
1321 * No special handling is actually required here.
1322 * It might be nice someday to preprocess the file list and
1323 * provide it to the client, though.
1324 */
1325 archive_entry_set_filetype(entry, AE_IFDIR);
1326 break;
1327 case 'M': /* GNU "Multi-volume" (remainder of file from last archive)*/
1328 /*
1329 * As far as I can tell, this is just like a regular file
1330 * entry, except that the contents should be _appended_ to
1331 * the indicated file at the indicated offset. This may
1332 * require some API work to fully support.
1333 */
1334 break;
1335 case 'N': /* Old GNU "long filename" entry. */
1336 /* The body of this entry is a script for renaming
1337 * previously-extracted entries. Ugh. It will never
1338 * be supported by libarchive. */
1339 archive_entry_set_filetype(entry, AE_IFREG);
1340 break;
1341 case 'S': /* GNU sparse files */
1342 /*
1343 * Sparse files are really just regular files with
1344 * sparse information in the extended area.
1345 */
1346 /* FALLTHROUGH */
1347 case '0':
1348 /*
1349 * Enable sparse file "read" support only for regular
1350 * files and explicit GNU sparse files. However, we
1351 * don't allow non-standard file types to be sparse.
1352 */
1353 tar->sparse_allowed = 1;
1354 /* FALLTHROUGH */
1355 default: /* Regular file and non-standard types */
1356 /*
1357 * Per POSIX: non-recognized types should always be
1358 * treated as regular files.
1359 */
1360 archive_entry_set_filetype(entry, AE_IFREG);
1361 break;
1362 }
1363 return (err);
1364 }
1365
1366 /*
1367 * Parse out header elements for "old-style" tar archives.
1368 */
1369 static int
header_old_tar(struct archive_read * a,struct tar * tar,struct archive_entry * entry,const void * h)1370 header_old_tar(struct archive_read *a, struct tar *tar,
1371 struct archive_entry *entry, const void *h)
1372 {
1373 const struct archive_entry_header_ustar *header;
1374 int err = ARCHIVE_OK, err2;
1375
1376 /* Copy filename over (to ensure null termination). */
1377 header = (const struct archive_entry_header_ustar *)h;
1378 if (archive_entry_copy_pathname_l(entry,
1379 header->name, sizeof(header->name), tar->sconv) != 0) {
1380 err = set_conversion_failed_error(a, tar->sconv, "Pathname");
1381 if (err == ARCHIVE_FATAL)
1382 return (err);
1383 }
1384
1385 /* Grab rest of common fields */
1386 err2 = header_common(a, tar, entry, h);
1387 if (err > err2)
1388 err = err2;
1389
1390 tar->entry_padding = 0x1ff & (-tar->entry_bytes_remaining);
1391 return (err);
1392 }
1393
1394 /*
1395 * Read a Mac AppleDouble-encoded blob of file metadata,
1396 * if there is one.
1397 */
1398 static int
read_mac_metadata_blob(struct archive_read * a,struct tar * tar,struct archive_entry * entry,const void * h,size_t * unconsumed)1399 read_mac_metadata_blob(struct archive_read *a, struct tar *tar,
1400 struct archive_entry *entry, const void *h, size_t *unconsumed)
1401 {
1402 int64_t size;
1403 size_t msize;
1404 const void *data;
1405 const char *p, *name;
1406 const wchar_t *wp, *wname;
1407
1408 (void)h; /* UNUSED */
1409
1410 wname = wp = archive_entry_pathname_w(entry);
1411 if (wp != NULL) {
1412 /* Find the last path element. */
1413 for (; *wp != L'\0'; ++wp) {
1414 if (wp[0] == '/' && wp[1] != L'\0')
1415 wname = wp + 1;
1416 }
1417 /*
1418 * If last path element starts with "._", then
1419 * this is a Mac extension.
1420 */
1421 if (wname[0] != L'.' || wname[1] != L'_' || wname[2] == L'\0')
1422 return ARCHIVE_OK;
1423 } else {
1424 /* Find the last path element. */
1425 name = p = archive_entry_pathname(entry);
1426 if (p == NULL)
1427 return (ARCHIVE_FAILED);
1428 for (; *p != '\0'; ++p) {
1429 if (p[0] == '/' && p[1] != '\0')
1430 name = p + 1;
1431 }
1432 /*
1433 * If last path element starts with "._", then
1434 * this is a Mac extension.
1435 */
1436 if (name[0] != '.' || name[1] != '_' || name[2] == '\0')
1437 return ARCHIVE_OK;
1438 }
1439
1440 /* Read the body as a Mac OS metadata blob. */
1441 size = archive_entry_size(entry);
1442 msize = (size_t)size;
1443 if (size < 0 || (uintmax_t)msize != (uintmax_t)size) {
1444 *unconsumed = 0;
1445 return (ARCHIVE_FATAL);
1446 }
1447
1448 /*
1449 * TODO: Look beyond the body here to peek at the next header.
1450 * If it's a regular header (not an extension header)
1451 * that has the wrong name, just return the current
1452 * entry as-is, without consuming the body here.
1453 * That would reduce the risk of us mis-identifying
1454 * an ordinary file that just happened to have
1455 * a name starting with "._".
1456 *
1457 * Q: Is the above idea really possible? Even
1458 * when there are GNU or pax extension entries?
1459 */
1460 data = __archive_read_ahead(a, msize, NULL);
1461 if (data == NULL) {
1462 *unconsumed = 0;
1463 return (ARCHIVE_FATAL);
1464 }
1465 archive_entry_copy_mac_metadata(entry, data, msize);
1466 *unconsumed = (msize + 511) & ~ 511;
1467 tar_flush_unconsumed(a, unconsumed);
1468 return (tar_read_header(a, tar, entry, unconsumed));
1469 }
1470
1471 /*
1472 * Parse a file header for a pax extended archive entry.
1473 */
1474 static int
header_pax_global(struct archive_read * a,struct tar * tar,struct archive_entry * entry,const void * h,size_t * unconsumed)1475 header_pax_global(struct archive_read *a, struct tar *tar,
1476 struct archive_entry *entry, const void *h, size_t *unconsumed)
1477 {
1478 int err;
1479
1480 err = read_body_to_string(a, tar, &(tar->pax_global), h, unconsumed);
1481 if (err != ARCHIVE_OK)
1482 return (err);
1483 err = tar_read_header(a, tar, entry, unconsumed);
1484 return (err);
1485 }
1486
1487 static int
header_pax_extensions(struct archive_read * a,struct tar * tar,struct archive_entry * entry,const void * h,size_t * unconsumed)1488 header_pax_extensions(struct archive_read *a, struct tar *tar,
1489 struct archive_entry *entry, const void *h, size_t *unconsumed)
1490 {
1491 int err, err2;
1492
1493 err = read_body_to_string(a, tar, &(tar->pax_header), h, unconsumed);
1494 if (err != ARCHIVE_OK)
1495 return (err);
1496
1497 /* Parse the next header. */
1498 err = tar_read_header(a, tar, entry, unconsumed);
1499 if ((err != ARCHIVE_OK) && (err != ARCHIVE_WARN))
1500 return (err);
1501
1502 /*
1503 * TODO: Parse global/default options into 'entry' struct here
1504 * before handling file-specific options.
1505 *
1506 * This design (parse standard header, then overwrite with pax
1507 * extended attribute data) usually works well, but isn't ideal;
1508 * it would be better to parse the pax extended attributes first
1509 * and then skip any fields in the standard header that were
1510 * defined in the pax header.
1511 */
1512 err2 = pax_header(a, tar, entry, &tar->pax_header);
1513 err = err_combine(err, err2);
1514 tar->entry_padding = 0x1ff & (-tar->entry_bytes_remaining);
1515 return (err);
1516 }
1517
1518
1519 /*
1520 * Parse a file header for a Posix "ustar" archive entry. This also
1521 * handles "pax" or "extended ustar" entries.
1522 */
1523 static int
header_ustar(struct archive_read * a,struct tar * tar,struct archive_entry * entry,const void * h)1524 header_ustar(struct archive_read *a, struct tar *tar,
1525 struct archive_entry *entry, const void *h)
1526 {
1527 const struct archive_entry_header_ustar *header;
1528 struct archive_string *as;
1529 int err = ARCHIVE_OK, r;
1530
1531 header = (const struct archive_entry_header_ustar *)h;
1532
1533 /* Copy name into an internal buffer to ensure null-termination. */
1534 as = &(tar->entry_pathname);
1535 if (header->prefix[0]) {
1536 archive_strncpy(as, header->prefix, sizeof(header->prefix));
1537 if (as->s[archive_strlen(as) - 1] != '/')
1538 archive_strappend_char(as, '/');
1539 archive_strncat(as, header->name, sizeof(header->name));
1540 } else {
1541 archive_strncpy(as, header->name, sizeof(header->name));
1542 }
1543 if (archive_entry_copy_pathname_l(entry, as->s, archive_strlen(as),
1544 tar->sconv) != 0) {
1545 err = set_conversion_failed_error(a, tar->sconv, "Pathname");
1546 if (err == ARCHIVE_FATAL)
1547 return (err);
1548 }
1549
1550 /* Handle rest of common fields. */
1551 r = header_common(a, tar, entry, h);
1552 if (r == ARCHIVE_FATAL)
1553 return (r);
1554 if (r < err)
1555 err = r;
1556
1557 /* Handle POSIX ustar fields. */
1558 if (archive_entry_copy_uname_l(entry,
1559 header->uname, sizeof(header->uname), tar->sconv) != 0) {
1560 err = set_conversion_failed_error(a, tar->sconv, "Uname");
1561 if (err == ARCHIVE_FATAL)
1562 return (err);
1563 }
1564
1565 if (archive_entry_copy_gname_l(entry,
1566 header->gname, sizeof(header->gname), tar->sconv) != 0) {
1567 err = set_conversion_failed_error(a, tar->sconv, "Gname");
1568 if (err == ARCHIVE_FATAL)
1569 return (err);
1570 }
1571
1572 /* Parse out device numbers only for char and block specials. */
1573 if (header->typeflag[0] == '3' || header->typeflag[0] == '4') {
1574 archive_entry_set_rdevmajor(entry, (dev_t)
1575 tar_atol(header->rdevmajor, sizeof(header->rdevmajor)));
1576 archive_entry_set_rdevminor(entry, (dev_t)
1577 tar_atol(header->rdevminor, sizeof(header->rdevminor)));
1578 }
1579
1580 tar->entry_padding = 0x1ff & (-tar->entry_bytes_remaining);
1581
1582 return (err);
1583 }
1584
1585
1586 /*
1587 * Parse the pax extended attributes record.
1588 *
1589 * Returns non-zero if there's an error in the data.
1590 */
1591 static int
pax_header(struct archive_read * a,struct tar * tar,struct archive_entry * entry,struct archive_string * in_as)1592 pax_header(struct archive_read *a, struct tar *tar,
1593 struct archive_entry *entry, struct archive_string *in_as)
1594 {
1595 size_t attr_length, l, line_length, value_length;
1596 char *p;
1597 char *key, *value;
1598 struct archive_string *as;
1599 struct archive_string_conv *sconv;
1600 int err, err2;
1601 char *attr = in_as->s;
1602
1603 attr_length = in_as->length;
1604 tar->pax_hdrcharset_binary = 0;
1605 archive_string_empty(&(tar->entry_gname));
1606 archive_string_empty(&(tar->entry_linkpath));
1607 archive_string_empty(&(tar->entry_pathname));
1608 archive_string_empty(&(tar->entry_pathname_override));
1609 archive_string_empty(&(tar->entry_uname));
1610 err = ARCHIVE_OK;
1611 while (attr_length > 0) {
1612 /* Parse decimal length field at start of line. */
1613 line_length = 0;
1614 l = attr_length;
1615 p = attr; /* Record start of line. */
1616 while (l>0) {
1617 if (*p == ' ') {
1618 p++;
1619 l--;
1620 break;
1621 }
1622 if (*p < '0' || *p > '9') {
1623 archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1624 "Ignoring malformed pax extended attributes");
1625 return (ARCHIVE_WARN);
1626 }
1627 line_length *= 10;
1628 line_length += *p - '0';
1629 if (line_length > 999999) {
1630 archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1631 "Rejecting pax extended attribute > 1MB");
1632 return (ARCHIVE_WARN);
1633 }
1634 p++;
1635 l--;
1636 }
1637
1638 /*
1639 * Parsed length must be no bigger than available data,
1640 * at least 1, and the last character of the line must
1641 * be '\n'.
1642 */
1643 if (line_length > attr_length
1644 || line_length < 1
1645 || attr[line_length - 1] != '\n')
1646 {
1647 archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1648 "Ignoring malformed pax extended attribute");
1649 return (ARCHIVE_WARN);
1650 }
1651
1652 /* Null-terminate the line. */
1653 attr[line_length - 1] = '\0';
1654
1655 /* Find end of key and null terminate it. */
1656 key = p;
1657 if (key[0] == '=')
1658 return (-1);
1659 while (*p && *p != '=')
1660 ++p;
1661 if (*p == '\0') {
1662 archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1663 "Invalid pax extended attributes");
1664 return (ARCHIVE_WARN);
1665 }
1666 *p = '\0';
1667
1668 value = p + 1;
1669
1670 /* Some values may be binary data */
1671 value_length = attr + line_length - 1 - value;
1672
1673 /* Identify this attribute and set it in the entry. */
1674 err2 = pax_attribute(a, tar, entry, key, value, value_length);
1675 if (err2 == ARCHIVE_FATAL)
1676 return (err2);
1677 err = err_combine(err, err2);
1678
1679 /* Skip to next line */
1680 attr += line_length;
1681 attr_length -= line_length;
1682 }
1683
1684 /*
1685 * PAX format uses UTF-8 as default charset for its metadata
1686 * unless hdrcharset=BINARY is present in its header.
1687 * We apply the charset specified by the hdrcharset option only
1688 * when the hdrcharset attribute(in PAX header) is BINARY because
1689 * we respect the charset described in PAX header and BINARY also
1690 * means that metadata(filename,uname and gname) character-set
1691 * is unknown.
1692 */
1693 if (tar->pax_hdrcharset_binary)
1694 sconv = tar->opt_sconv;
1695 else {
1696 sconv = archive_string_conversion_from_charset(
1697 &(a->archive), "UTF-8", 1);
1698 if (sconv == NULL)
1699 return (ARCHIVE_FATAL);
1700 if (tar->compat_2x)
1701 archive_string_conversion_set_opt(sconv,
1702 SCONV_SET_OPT_UTF8_LIBARCHIVE2X);
1703 }
1704
1705 if (archive_strlen(&(tar->entry_gname)) > 0) {
1706 if (archive_entry_copy_gname_l(entry, tar->entry_gname.s,
1707 archive_strlen(&(tar->entry_gname)), sconv) != 0) {
1708 err = set_conversion_failed_error(a, sconv, "Gname");
1709 if (err == ARCHIVE_FATAL)
1710 return (err);
1711 /* Use a converted an original name. */
1712 archive_entry_copy_gname(entry, tar->entry_gname.s);
1713 }
1714 }
1715 if (archive_strlen(&(tar->entry_linkpath)) > 0) {
1716 if (archive_entry_copy_link_l(entry, tar->entry_linkpath.s,
1717 archive_strlen(&(tar->entry_linkpath)), sconv) != 0) {
1718 err = set_conversion_failed_error(a, sconv, "Linkname");
1719 if (err == ARCHIVE_FATAL)
1720 return (err);
1721 /* Use a converted an original name. */
1722 archive_entry_copy_link(entry, tar->entry_linkpath.s);
1723 }
1724 }
1725 /*
1726 * Some extensions (such as the GNU sparse file extensions)
1727 * deliberately store a synthetic name under the regular 'path'
1728 * attribute and the real file name under a different attribute.
1729 * Since we're supposed to not care about the order, we
1730 * have no choice but to store all of the various filenames
1731 * we find and figure it all out afterwards. This is the
1732 * figuring out part.
1733 */
1734 as = NULL;
1735 if (archive_strlen(&(tar->entry_pathname_override)) > 0)
1736 as = &(tar->entry_pathname_override);
1737 else if (archive_strlen(&(tar->entry_pathname)) > 0)
1738 as = &(tar->entry_pathname);
1739 if (as != NULL) {
1740 if (archive_entry_copy_pathname_l(entry, as->s,
1741 archive_strlen(as), sconv) != 0) {
1742 err = set_conversion_failed_error(a, sconv, "Pathname");
1743 if (err == ARCHIVE_FATAL)
1744 return (err);
1745 /* Use a converted an original name. */
1746 archive_entry_copy_pathname(entry, as->s);
1747 }
1748 }
1749 if (archive_strlen(&(tar->entry_uname)) > 0) {
1750 if (archive_entry_copy_uname_l(entry, tar->entry_uname.s,
1751 archive_strlen(&(tar->entry_uname)), sconv) != 0) {
1752 err = set_conversion_failed_error(a, sconv, "Uname");
1753 if (err == ARCHIVE_FATAL)
1754 return (err);
1755 /* Use a converted an original name. */
1756 archive_entry_copy_uname(entry, tar->entry_uname.s);
1757 }
1758 }
1759 return (err);
1760 }
1761
1762 static int
pax_attribute_xattr(struct archive_entry * entry,const char * name,const char * value)1763 pax_attribute_xattr(struct archive_entry *entry,
1764 const char *name, const char *value)
1765 {
1766 char *name_decoded;
1767 void *value_decoded;
1768 size_t value_len;
1769
1770 if (strlen(name) < 18 || (memcmp(name, "LIBARCHIVE.xattr.", 17)) != 0)
1771 return 3;
1772
1773 name += 17;
1774
1775 /* URL-decode name */
1776 name_decoded = url_decode(name);
1777 if (name_decoded == NULL)
1778 return 2;
1779
1780 /* Base-64 decode value */
1781 value_decoded = base64_decode(value, strlen(value), &value_len);
1782 if (value_decoded == NULL) {
1783 free(name_decoded);
1784 return 1;
1785 }
1786
1787 archive_entry_xattr_add_entry(entry, name_decoded,
1788 value_decoded, value_len);
1789
1790 free(name_decoded);
1791 free(value_decoded);
1792 return 0;
1793 }
1794
1795 static int
pax_attribute_schily_xattr(struct archive_entry * entry,const char * name,const char * value,size_t value_length)1796 pax_attribute_schily_xattr(struct archive_entry *entry,
1797 const char *name, const char *value, size_t value_length)
1798 {
1799 if (strlen(name) < 14 || (memcmp(name, "SCHILY.xattr.", 13)) != 0)
1800 return 1;
1801
1802 name += 13;
1803
1804 archive_entry_xattr_add_entry(entry, name, value, value_length);
1805
1806 return 0;
1807 }
1808
1809 static int
pax_attribute_rht_security_selinux(struct archive_entry * entry,const char * value,size_t value_length)1810 pax_attribute_rht_security_selinux(struct archive_entry *entry,
1811 const char *value, size_t value_length)
1812 {
1813 archive_entry_xattr_add_entry(entry, "security.selinux",
1814 value, value_length);
1815
1816 return 0;
1817 }
1818
1819 static int
pax_attribute_acl(struct archive_read * a,struct tar * tar,struct archive_entry * entry,const char * value,int type)1820 pax_attribute_acl(struct archive_read *a, struct tar *tar,
1821 struct archive_entry *entry, const char *value, int type)
1822 {
1823 int r;
1824 const char* errstr;
1825
1826 switch (type) {
1827 case ARCHIVE_ENTRY_ACL_TYPE_ACCESS:
1828 errstr = "SCHILY.acl.access";
1829 break;
1830 case ARCHIVE_ENTRY_ACL_TYPE_DEFAULT:
1831 errstr = "SCHILY.acl.default";
1832 break;
1833 case ARCHIVE_ENTRY_ACL_TYPE_NFS4:
1834 errstr = "SCHILY.acl.ace";
1835 break;
1836 default:
1837 archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1838 "Unknown ACL type: %d", type);
1839 return(ARCHIVE_FATAL);
1840 }
1841
1842 if (tar->sconv_acl == NULL) {
1843 tar->sconv_acl =
1844 archive_string_conversion_from_charset(
1845 &(a->archive), "UTF-8", 1);
1846 if (tar->sconv_acl == NULL)
1847 return (ARCHIVE_FATAL);
1848 }
1849
1850 r = archive_acl_from_text_l(archive_entry_acl(entry), value, type,
1851 tar->sconv_acl);
1852 if (r != ARCHIVE_OK) {
1853 if (r == ARCHIVE_FATAL) {
1854 archive_set_error(&a->archive, ENOMEM,
1855 "%s %s", "Can't allocate memory for ",
1856 errstr);
1857 return (r);
1858 }
1859 archive_set_error(&a->archive,
1860 ARCHIVE_ERRNO_MISC, "%s %s", "Parse error: ", errstr);
1861 }
1862 return (r);
1863 }
1864
1865 /*
1866 * Parse a single key=value attribute. key/value pointers are
1867 * assumed to point into reasonably long-lived storage.
1868 *
1869 * Note that POSIX reserves all-lowercase keywords. Vendor-specific
1870 * extensions should always have keywords of the form "VENDOR.attribute"
1871 * In particular, it's quite feasible to support many different
1872 * vendor extensions here. I'm using "LIBARCHIVE" for extensions
1873 * unique to this library.
1874 *
1875 * Investigate other vendor-specific extensions and see if
1876 * any of them look useful.
1877 */
1878 static int
pax_attribute(struct archive_read * a,struct tar * tar,struct archive_entry * entry,const char * key,const char * value,size_t value_length)1879 pax_attribute(struct archive_read *a, struct tar *tar,
1880 struct archive_entry *entry, const char *key, const char *value, size_t value_length)
1881 {
1882 int64_t s;
1883 long n;
1884 int err = ARCHIVE_OK, r;
1885
1886 if (value == NULL)
1887 value = ""; /* Disable compiler warning; do not pass
1888 * NULL pointer to strlen(). */
1889 switch (key[0]) {
1890 case 'G':
1891 /* Reject GNU.sparse.* headers on non-regular files. */
1892 if (strncmp(key, "GNU.sparse", 10) == 0 &&
1893 !tar->sparse_allowed) {
1894 archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1895 "Non-regular file cannot be sparse");
1896 return (ARCHIVE_FATAL);
1897 }
1898
1899 /* GNU "0.0" sparse pax format. */
1900 if (strcmp(key, "GNU.sparse.numblocks") == 0) {
1901 tar->sparse_offset = -1;
1902 tar->sparse_numbytes = -1;
1903 tar->sparse_gnu_major = 0;
1904 tar->sparse_gnu_minor = 0;
1905 }
1906 if (strcmp(key, "GNU.sparse.offset") == 0) {
1907 tar->sparse_offset = tar_atol10(value, strlen(value));
1908 if (tar->sparse_numbytes != -1) {
1909 if (gnu_add_sparse_entry(a, tar,
1910 tar->sparse_offset, tar->sparse_numbytes)
1911 != ARCHIVE_OK)
1912 return (ARCHIVE_FATAL);
1913 tar->sparse_offset = -1;
1914 tar->sparse_numbytes = -1;
1915 }
1916 }
1917 if (strcmp(key, "GNU.sparse.numbytes") == 0) {
1918 tar->sparse_numbytes = tar_atol10(value, strlen(value));
1919 if (tar->sparse_offset != -1) {
1920 if (gnu_add_sparse_entry(a, tar,
1921 tar->sparse_offset, tar->sparse_numbytes)
1922 != ARCHIVE_OK)
1923 return (ARCHIVE_FATAL);
1924 tar->sparse_offset = -1;
1925 tar->sparse_numbytes = -1;
1926 }
1927 }
1928 if (strcmp(key, "GNU.sparse.size") == 0) {
1929 tar->realsize = tar_atol10(value, strlen(value));
1930 archive_entry_set_size(entry, tar->realsize);
1931 tar->realsize_override = 1;
1932 }
1933
1934 /* GNU "0.1" sparse pax format. */
1935 if (strcmp(key, "GNU.sparse.map") == 0) {
1936 tar->sparse_gnu_major = 0;
1937 tar->sparse_gnu_minor = 1;
1938 if (gnu_sparse_01_parse(a, tar, value) != ARCHIVE_OK)
1939 return (ARCHIVE_WARN);
1940 }
1941
1942 /* GNU "1.0" sparse pax format */
1943 if (strcmp(key, "GNU.sparse.major") == 0) {
1944 tar->sparse_gnu_major = (int)tar_atol10(value, strlen(value));
1945 tar->sparse_gnu_pending = 1;
1946 }
1947 if (strcmp(key, "GNU.sparse.minor") == 0) {
1948 tar->sparse_gnu_minor = (int)tar_atol10(value, strlen(value));
1949 tar->sparse_gnu_pending = 1;
1950 }
1951 if (strcmp(key, "GNU.sparse.name") == 0) {
1952 /*
1953 * The real filename; when storing sparse
1954 * files, GNU tar puts a synthesized name into
1955 * the regular 'path' attribute in an attempt
1956 * to limit confusion. ;-)
1957 */
1958 archive_strcpy(&(tar->entry_pathname_override), value);
1959 }
1960 if (strcmp(key, "GNU.sparse.realsize") == 0) {
1961 tar->realsize = tar_atol10(value, strlen(value));
1962 archive_entry_set_size(entry, tar->realsize);
1963 tar->realsize_override = 1;
1964 }
1965 break;
1966 case 'L':
1967 /* Our extensions */
1968 /* TODO: Handle arbitrary extended attributes... */
1969 /*
1970 if (strcmp(key, "LIBARCHIVE.xxxxxxx") == 0)
1971 archive_entry_set_xxxxxx(entry, value);
1972 */
1973 if (strcmp(key, "LIBARCHIVE.creationtime") == 0) {
1974 pax_time(value, &s, &n);
1975 archive_entry_set_birthtime(entry, s, n);
1976 }
1977 if (strcmp(key, "LIBARCHIVE.symlinktype") == 0) {
1978 if (strcmp(value, "file") == 0) {
1979 archive_entry_set_symlink_type(entry,
1980 AE_SYMLINK_TYPE_FILE);
1981 } else if (strcmp(value, "dir") == 0) {
1982 archive_entry_set_symlink_type(entry,
1983 AE_SYMLINK_TYPE_DIRECTORY);
1984 }
1985 }
1986 if (memcmp(key, "LIBARCHIVE.xattr.", 17) == 0)
1987 pax_attribute_xattr(entry, key, value);
1988 break;
1989 case 'R':
1990 /* GNU tar uses RHT.security header to store SELinux xattrs
1991 * SCHILY.xattr.security.selinux == RHT.security.selinux */
1992 if (strcmp(key, "RHT.security.selinux") == 0) {
1993 pax_attribute_rht_security_selinux(entry, value,
1994 value_length);
1995 }
1996 break;
1997 case 'S':
1998 /* We support some keys used by the "star" archiver */
1999 if (strcmp(key, "SCHILY.acl.access") == 0) {
2000 r = pax_attribute_acl(a, tar, entry, value,
2001 ARCHIVE_ENTRY_ACL_TYPE_ACCESS);
2002 if (r == ARCHIVE_FATAL)
2003 return (r);
2004 } else if (strcmp(key, "SCHILY.acl.default") == 0) {
2005 r = pax_attribute_acl(a, tar, entry, value,
2006 ARCHIVE_ENTRY_ACL_TYPE_DEFAULT);
2007 if (r == ARCHIVE_FATAL)
2008 return (r);
2009 } else if (strcmp(key, "SCHILY.acl.ace") == 0) {
2010 r = pax_attribute_acl(a, tar, entry, value,
2011 ARCHIVE_ENTRY_ACL_TYPE_NFS4);
2012 if (r == ARCHIVE_FATAL)
2013 return (r);
2014 } else if (strcmp(key, "SCHILY.devmajor") == 0) {
2015 archive_entry_set_rdevmajor(entry,
2016 (dev_t)tar_atol10(value, strlen(value)));
2017 } else if (strcmp(key, "SCHILY.devminor") == 0) {
2018 archive_entry_set_rdevminor(entry,
2019 (dev_t)tar_atol10(value, strlen(value)));
2020 } else if (strcmp(key, "SCHILY.fflags") == 0) {
2021 archive_entry_copy_fflags_text(entry, value);
2022 } else if (strcmp(key, "SCHILY.dev") == 0) {
2023 archive_entry_set_dev(entry,
2024 (dev_t)tar_atol10(value, strlen(value)));
2025 } else if (strcmp(key, "SCHILY.ino") == 0) {
2026 archive_entry_set_ino(entry,
2027 tar_atol10(value, strlen(value)));
2028 } else if (strcmp(key, "SCHILY.nlink") == 0) {
2029 archive_entry_set_nlink(entry, (unsigned)
2030 tar_atol10(value, strlen(value)));
2031 } else if (strcmp(key, "SCHILY.realsize") == 0) {
2032 tar->realsize = tar_atol10(value, strlen(value));
2033 tar->realsize_override = 1;
2034 archive_entry_set_size(entry, tar->realsize);
2035 } else if (strncmp(key, "SCHILY.xattr.", 13) == 0) {
2036 pax_attribute_schily_xattr(entry, key, value,
2037 value_length);
2038 } else if (strcmp(key, "SUN.holesdata") == 0) {
2039 /* A Solaris extension for sparse. */
2040 r = solaris_sparse_parse(a, tar, entry, value);
2041 if (r < err) {
2042 if (r == ARCHIVE_FATAL)
2043 return (r);
2044 err = r;
2045 archive_set_error(&a->archive,
2046 ARCHIVE_ERRNO_MISC,
2047 "Parse error: SUN.holesdata");
2048 }
2049 }
2050 break;
2051 case 'a':
2052 if (strcmp(key, "atime") == 0) {
2053 pax_time(value, &s, &n);
2054 archive_entry_set_atime(entry, s, n);
2055 }
2056 break;
2057 case 'c':
2058 if (strcmp(key, "ctime") == 0) {
2059 pax_time(value, &s, &n);
2060 archive_entry_set_ctime(entry, s, n);
2061 } else if (strcmp(key, "charset") == 0) {
2062 /* TODO: Publish charset information in entry. */
2063 } else if (strcmp(key, "comment") == 0) {
2064 /* TODO: Publish comment in entry. */
2065 }
2066 break;
2067 case 'g':
2068 if (strcmp(key, "gid") == 0) {
2069 archive_entry_set_gid(entry,
2070 tar_atol10(value, strlen(value)));
2071 } else if (strcmp(key, "gname") == 0) {
2072 archive_strcpy(&(tar->entry_gname), value);
2073 }
2074 break;
2075 case 'h':
2076 if (strcmp(key, "hdrcharset") == 0) {
2077 if (strcmp(value, "BINARY") == 0)
2078 /* Binary mode. */
2079 tar->pax_hdrcharset_binary = 1;
2080 else if (strcmp(value, "ISO-IR 10646 2000 UTF-8") == 0)
2081 tar->pax_hdrcharset_binary = 0;
2082 }
2083 break;
2084 case 'l':
2085 /* pax interchange doesn't distinguish hardlink vs. symlink. */
2086 if (strcmp(key, "linkpath") == 0) {
2087 archive_strcpy(&(tar->entry_linkpath), value);
2088 }
2089 break;
2090 case 'm':
2091 if (strcmp(key, "mtime") == 0) {
2092 pax_time(value, &s, &n);
2093 archive_entry_set_mtime(entry, s, n);
2094 }
2095 break;
2096 case 'p':
2097 if (strcmp(key, "path") == 0) {
2098 archive_strcpy(&(tar->entry_pathname), value);
2099 }
2100 break;
2101 case 'r':
2102 /* POSIX has reserved 'realtime.*' */
2103 break;
2104 case 's':
2105 /* POSIX has reserved 'security.*' */
2106 /* Someday: if (strcmp(key, "security.acl") == 0) { ... } */
2107 if (strcmp(key, "size") == 0) {
2108 /* "size" is the size of the data in the entry. */
2109 tar->entry_bytes_remaining
2110 = tar_atol10(value, strlen(value));
2111 /*
2112 * The "size" pax header keyword always overrides the
2113 * "size" field in the tar header.
2114 * GNU.sparse.realsize, GNU.sparse.size and
2115 * SCHILY.realsize override this value.
2116 */
2117 if (!tar->realsize_override) {
2118 archive_entry_set_size(entry,
2119 tar->entry_bytes_remaining);
2120 tar->realsize
2121 = tar->entry_bytes_remaining;
2122 }
2123 }
2124 break;
2125 case 'u':
2126 if (strcmp(key, "uid") == 0) {
2127 archive_entry_set_uid(entry,
2128 tar_atol10(value, strlen(value)));
2129 } else if (strcmp(key, "uname") == 0) {
2130 archive_strcpy(&(tar->entry_uname), value);
2131 }
2132 break;
2133 }
2134 return (err);
2135 }
2136
2137
2138
2139 /*
2140 * parse a decimal time value, which may include a fractional portion
2141 */
2142 static void
pax_time(const char * p,int64_t * ps,long * pn)2143 pax_time(const char *p, int64_t *ps, long *pn)
2144 {
2145 char digit;
2146 int64_t s;
2147 unsigned long l;
2148 int sign;
2149 int64_t limit, last_digit_limit;
2150
2151 limit = INT64_MAX / 10;
2152 last_digit_limit = INT64_MAX % 10;
2153
2154 s = 0;
2155 sign = 1;
2156 if (*p == '-') {
2157 sign = -1;
2158 p++;
2159 }
2160 while (*p >= '0' && *p <= '9') {
2161 digit = *p - '0';
2162 if (s > limit ||
2163 (s == limit && digit > last_digit_limit)) {
2164 s = INT64_MAX;
2165 break;
2166 }
2167 s = (s * 10) + digit;
2168 ++p;
2169 }
2170
2171 *ps = s * sign;
2172
2173 /* Calculate nanoseconds. */
2174 *pn = 0;
2175
2176 if (*p != '.')
2177 return;
2178
2179 l = 100000000UL;
2180 do {
2181 ++p;
2182 if (*p >= '0' && *p <= '9')
2183 *pn += (*p - '0') * l;
2184 else
2185 break;
2186 } while (l /= 10);
2187 }
2188
2189 /*
2190 * Parse GNU tar header
2191 */
2192 static int
header_gnutar(struct archive_read * a,struct tar * tar,struct archive_entry * entry,const void * h,size_t * unconsumed)2193 header_gnutar(struct archive_read *a, struct tar *tar,
2194 struct archive_entry *entry, const void *h, size_t *unconsumed)
2195 {
2196 const struct archive_entry_header_gnutar *header;
2197 int64_t t;
2198 int err = ARCHIVE_OK;
2199
2200 /*
2201 * GNU header is like POSIX ustar, except 'prefix' is
2202 * replaced with some other fields. This also means the
2203 * filename is stored as in old-style archives.
2204 */
2205
2206 /* Grab fields common to all tar variants. */
2207 err = header_common(a, tar, entry, h);
2208 if (err == ARCHIVE_FATAL)
2209 return (err);
2210
2211 /* Copy filename over (to ensure null termination). */
2212 header = (const struct archive_entry_header_gnutar *)h;
2213 if (archive_entry_copy_pathname_l(entry,
2214 header->name, sizeof(header->name), tar->sconv) != 0) {
2215 err = set_conversion_failed_error(a, tar->sconv, "Pathname");
2216 if (err == ARCHIVE_FATAL)
2217 return (err);
2218 }
2219
2220 /* Fields common to ustar and GNU */
2221 /* XXX Can the following be factored out since it's common
2222 * to ustar and gnu tar? Is it okay to move it down into
2223 * header_common, perhaps? */
2224 if (archive_entry_copy_uname_l(entry,
2225 header->uname, sizeof(header->uname), tar->sconv) != 0) {
2226 err = set_conversion_failed_error(a, tar->sconv, "Uname");
2227 if (err == ARCHIVE_FATAL)
2228 return (err);
2229 }
2230
2231 if (archive_entry_copy_gname_l(entry,
2232 header->gname, sizeof(header->gname), tar->sconv) != 0) {
2233 err = set_conversion_failed_error(a, tar->sconv, "Gname");
2234 if (err == ARCHIVE_FATAL)
2235 return (err);
2236 }
2237
2238 /* Parse out device numbers only for char and block specials */
2239 if (header->typeflag[0] == '3' || header->typeflag[0] == '4') {
2240 archive_entry_set_rdevmajor(entry, (dev_t)
2241 tar_atol(header->rdevmajor, sizeof(header->rdevmajor)));
2242 archive_entry_set_rdevminor(entry, (dev_t)
2243 tar_atol(header->rdevminor, sizeof(header->rdevminor)));
2244 } else
2245 archive_entry_set_rdev(entry, 0);
2246
2247 tar->entry_padding = 0x1ff & (-tar->entry_bytes_remaining);
2248
2249 /* Grab GNU-specific fields. */
2250 t = tar_atol(header->atime, sizeof(header->atime));
2251 if (t > 0)
2252 archive_entry_set_atime(entry, t, 0);
2253 t = tar_atol(header->ctime, sizeof(header->ctime));
2254 if (t > 0)
2255 archive_entry_set_ctime(entry, t, 0);
2256
2257 if (header->realsize[0] != 0) {
2258 tar->realsize
2259 = tar_atol(header->realsize, sizeof(header->realsize));
2260 archive_entry_set_size(entry, tar->realsize);
2261 tar->realsize_override = 1;
2262 }
2263
2264 if (header->sparse[0].offset[0] != 0) {
2265 if (gnu_sparse_old_read(a, tar, header, unconsumed)
2266 != ARCHIVE_OK)
2267 return (ARCHIVE_FATAL);
2268 } else {
2269 if (header->isextended[0] != 0) {
2270 /* XXX WTF? XXX */
2271 }
2272 }
2273
2274 return (err);
2275 }
2276
2277 static int
gnu_add_sparse_entry(struct archive_read * a,struct tar * tar,int64_t offset,int64_t remaining)2278 gnu_add_sparse_entry(struct archive_read *a, struct tar *tar,
2279 int64_t offset, int64_t remaining)
2280 {
2281 struct sparse_block *p;
2282
2283 p = (struct sparse_block *)calloc(1, sizeof(*p));
2284 if (p == NULL) {
2285 archive_set_error(&a->archive, ENOMEM, "Out of memory");
2286 return (ARCHIVE_FATAL);
2287 }
2288 if (tar->sparse_last != NULL)
2289 tar->sparse_last->next = p;
2290 else
2291 tar->sparse_list = p;
2292 tar->sparse_last = p;
2293 if (remaining < 0 || offset < 0 || offset > INT64_MAX - remaining) {
2294 archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC, "Malformed sparse map data");
2295 return (ARCHIVE_FATAL);
2296 }
2297 p->offset = offset;
2298 p->remaining = remaining;
2299 return (ARCHIVE_OK);
2300 }
2301
2302 static void
gnu_clear_sparse_list(struct tar * tar)2303 gnu_clear_sparse_list(struct tar *tar)
2304 {
2305 struct sparse_block *p;
2306
2307 while (tar->sparse_list != NULL) {
2308 p = tar->sparse_list;
2309 tar->sparse_list = p->next;
2310 free(p);
2311 }
2312 tar->sparse_last = NULL;
2313 }
2314
2315 /*
2316 * GNU tar old-format sparse data.
2317 *
2318 * GNU old-format sparse data is stored in a fixed-field
2319 * format. Offset/size values are 11-byte octal fields (same
2320 * format as 'size' field in ustart header). These are
2321 * stored in the header, allocating subsequent header blocks
2322 * as needed. Extending the header in this way is a pretty
2323 * severe POSIX violation; this design has earned GNU tar a
2324 * lot of criticism.
2325 */
2326
2327 static int
gnu_sparse_old_read(struct archive_read * a,struct tar * tar,const struct archive_entry_header_gnutar * header,size_t * unconsumed)2328 gnu_sparse_old_read(struct archive_read *a, struct tar *tar,
2329 const struct archive_entry_header_gnutar *header, size_t *unconsumed)
2330 {
2331 ssize_t bytes_read;
2332 const void *data;
2333 struct extended {
2334 struct gnu_sparse sparse[21];
2335 char isextended[1];
2336 char padding[7];
2337 };
2338 const struct extended *ext;
2339
2340 if (gnu_sparse_old_parse(a, tar, header->sparse, 4) != ARCHIVE_OK)
2341 return (ARCHIVE_FATAL);
2342 if (header->isextended[0] == 0)
2343 return (ARCHIVE_OK);
2344
2345 do {
2346 tar_flush_unconsumed(a, unconsumed);
2347 data = __archive_read_ahead(a, 512, &bytes_read);
2348 if (bytes_read < 0)
2349 return (ARCHIVE_FATAL);
2350 if (bytes_read < 512) {
2351 archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
2352 "Truncated tar archive "
2353 "detected while reading sparse file data");
2354 return (ARCHIVE_FATAL);
2355 }
2356 *unconsumed = 512;
2357 ext = (const struct extended *)data;
2358 if (gnu_sparse_old_parse(a, tar, ext->sparse, 21) != ARCHIVE_OK)
2359 return (ARCHIVE_FATAL);
2360 } while (ext->isextended[0] != 0);
2361 if (tar->sparse_list != NULL)
2362 tar->entry_offset = tar->sparse_list->offset;
2363 return (ARCHIVE_OK);
2364 }
2365
2366 static int
gnu_sparse_old_parse(struct archive_read * a,struct tar * tar,const struct gnu_sparse * sparse,int length)2367 gnu_sparse_old_parse(struct archive_read *a, struct tar *tar,
2368 const struct gnu_sparse *sparse, int length)
2369 {
2370 while (length > 0 && sparse->offset[0] != 0) {
2371 if (gnu_add_sparse_entry(a, tar,
2372 tar_atol(sparse->offset, sizeof(sparse->offset)),
2373 tar_atol(sparse->numbytes, sizeof(sparse->numbytes)))
2374 != ARCHIVE_OK)
2375 return (ARCHIVE_FATAL);
2376 sparse++;
2377 length--;
2378 }
2379 return (ARCHIVE_OK);
2380 }
2381
2382 /*
2383 * GNU tar sparse format 0.0
2384 *
2385 * Beginning with GNU tar 1.15, sparse files are stored using
2386 * information in the pax extended header. The GNU tar maintainers
2387 * have gone through a number of variations in the process of working
2388 * out this scheme; fortunately, they're all numbered.
2389 *
2390 * Sparse format 0.0 uses attribute GNU.sparse.numblocks to store the
2391 * number of blocks, and GNU.sparse.offset/GNU.sparse.numbytes to
2392 * store offset/size for each block. The repeated instances of these
2393 * latter fields violate the pax specification (which frowns on
2394 * duplicate keys), so this format was quickly replaced.
2395 */
2396
2397 /*
2398 * GNU tar sparse format 0.1
2399 *
2400 * This version replaced the offset/numbytes attributes with
2401 * a single "map" attribute that stored a list of integers. This
2402 * format had two problems: First, the "map" attribute could be very
2403 * long, which caused problems for some implementations. More
2404 * importantly, the sparse data was lost when extracted by archivers
2405 * that didn't recognize this extension.
2406 */
2407
2408 static int
gnu_sparse_01_parse(struct archive_read * a,struct tar * tar,const char * p)2409 gnu_sparse_01_parse(struct archive_read *a, struct tar *tar, const char *p)
2410 {
2411 const char *e;
2412 int64_t offset = -1, size = -1;
2413
2414 for (;;) {
2415 e = p;
2416 while (*e != '\0' && *e != ',') {
2417 if (*e < '0' || *e > '9')
2418 return (ARCHIVE_WARN);
2419 e++;
2420 }
2421 if (offset < 0) {
2422 offset = tar_atol10(p, e - p);
2423 if (offset < 0)
2424 return (ARCHIVE_WARN);
2425 } else {
2426 size = tar_atol10(p, e - p);
2427 if (size < 0)
2428 return (ARCHIVE_WARN);
2429 if (gnu_add_sparse_entry(a, tar, offset, size)
2430 != ARCHIVE_OK)
2431 return (ARCHIVE_FATAL);
2432 offset = -1;
2433 }
2434 if (*e == '\0')
2435 return (ARCHIVE_OK);
2436 p = e + 1;
2437 }
2438 }
2439
2440 /*
2441 * GNU tar sparse format 1.0
2442 *
2443 * The idea: The offset/size data is stored as a series of base-10
2444 * ASCII numbers prepended to the file data, so that dearchivers that
2445 * don't support this format will extract the block map along with the
2446 * data and a separate post-process can restore the sparseness.
2447 *
2448 * Unfortunately, GNU tar 1.16 had a bug that added unnecessary
2449 * padding to the body of the file when using this format. GNU tar
2450 * 1.17 corrected this bug without bumping the version number, so
2451 * it's not possible to support both variants. This code supports
2452 * the later variant at the expense of not supporting the former.
2453 *
2454 * This variant also replaced GNU.sparse.size with GNU.sparse.realsize
2455 * and introduced the GNU.sparse.major/GNU.sparse.minor attributes.
2456 */
2457
2458 /*
2459 * Read the next line from the input, and parse it as a decimal
2460 * integer followed by '\n'. Returns positive integer value or
2461 * negative on error.
2462 */
2463 static int64_t
gnu_sparse_10_atol(struct archive_read * a,struct tar * tar,int64_t * remaining,size_t * unconsumed)2464 gnu_sparse_10_atol(struct archive_read *a, struct tar *tar,
2465 int64_t *remaining, size_t *unconsumed)
2466 {
2467 int64_t l, limit, last_digit_limit;
2468 const char *p;
2469 ssize_t bytes_read;
2470 int base, digit;
2471
2472 base = 10;
2473 limit = INT64_MAX / base;
2474 last_digit_limit = INT64_MAX % base;
2475
2476 /*
2477 * Skip any lines starting with '#'; GNU tar specs
2478 * don't require this, but they should.
2479 */
2480 do {
2481 bytes_read = readline(a, tar, &p,
2482 (ssize_t)tar_min(*remaining, 100), unconsumed);
2483 if (bytes_read <= 0)
2484 return (ARCHIVE_FATAL);
2485 *remaining -= bytes_read;
2486 } while (p[0] == '#');
2487
2488 l = 0;
2489 while (bytes_read > 0) {
2490 if (*p == '\n')
2491 return (l);
2492 if (*p < '0' || *p >= '0' + base)
2493 return (ARCHIVE_WARN);
2494 digit = *p - '0';
2495 if (l > limit || (l == limit && digit > last_digit_limit))
2496 l = INT64_MAX; /* Truncate on overflow. */
2497 else
2498 l = (l * base) + digit;
2499 p++;
2500 bytes_read--;
2501 }
2502 /* TODO: Error message. */
2503 return (ARCHIVE_WARN);
2504 }
2505
2506 /*
2507 * Returns length (in bytes) of the sparse data description
2508 * that was read.
2509 */
2510 static ssize_t
gnu_sparse_10_read(struct archive_read * a,struct tar * tar,size_t * unconsumed)2511 gnu_sparse_10_read(struct archive_read *a, struct tar *tar, size_t *unconsumed)
2512 {
2513 ssize_t bytes_read;
2514 int entries;
2515 int64_t offset, size, to_skip, remaining;
2516
2517 /* Clear out the existing sparse list. */
2518 gnu_clear_sparse_list(tar);
2519
2520 remaining = tar->entry_bytes_remaining;
2521
2522 /* Parse entries. */
2523 entries = (int)gnu_sparse_10_atol(a, tar, &remaining, unconsumed);
2524 if (entries < 0)
2525 return (ARCHIVE_FATAL);
2526 /* Parse the individual entries. */
2527 while (entries-- > 0) {
2528 /* Parse offset/size */
2529 offset = gnu_sparse_10_atol(a, tar, &remaining, unconsumed);
2530 if (offset < 0)
2531 return (ARCHIVE_FATAL);
2532 size = gnu_sparse_10_atol(a, tar, &remaining, unconsumed);
2533 if (size < 0)
2534 return (ARCHIVE_FATAL);
2535 /* Add a new sparse entry. */
2536 if (gnu_add_sparse_entry(a, tar, offset, size) != ARCHIVE_OK)
2537 return (ARCHIVE_FATAL);
2538 }
2539 /* Skip rest of block... */
2540 tar_flush_unconsumed(a, unconsumed);
2541 bytes_read = (ssize_t)(tar->entry_bytes_remaining - remaining);
2542 to_skip = 0x1ff & -bytes_read;
2543 /* Fail if tar->entry_bytes_remaing would get negative */
2544 if (to_skip > remaining)
2545 return (ARCHIVE_FATAL);
2546 if (to_skip != __archive_read_consume(a, to_skip))
2547 return (ARCHIVE_FATAL);
2548 return ((ssize_t)(bytes_read + to_skip));
2549 }
2550
2551 /*
2552 * Solaris pax extension for a sparse file. This is recorded with the
2553 * data and hole pairs. The way recording sparse information by Solaris'
2554 * pax simply indicates where data and sparse are, so the stored contents
2555 * consist of both data and hole.
2556 */
2557 static int
solaris_sparse_parse(struct archive_read * a,struct tar * tar,struct archive_entry * entry,const char * p)2558 solaris_sparse_parse(struct archive_read *a, struct tar *tar,
2559 struct archive_entry *entry, const char *p)
2560 {
2561 const char *e;
2562 int64_t start, end;
2563 int hole = 1;
2564
2565 (void)entry; /* UNUSED */
2566
2567 end = 0;
2568 if (*p == ' ')
2569 p++;
2570 else
2571 return (ARCHIVE_WARN);
2572 for (;;) {
2573 e = p;
2574 while (*e != '\0' && *e != ' ') {
2575 if (*e < '0' || *e > '9')
2576 return (ARCHIVE_WARN);
2577 e++;
2578 }
2579 start = end;
2580 end = tar_atol10(p, e - p);
2581 if (end < 0)
2582 return (ARCHIVE_WARN);
2583 if (start < end) {
2584 if (gnu_add_sparse_entry(a, tar, start,
2585 end - start) != ARCHIVE_OK)
2586 return (ARCHIVE_FATAL);
2587 tar->sparse_last->hole = hole;
2588 }
2589 if (*e == '\0')
2590 return (ARCHIVE_OK);
2591 p = e + 1;
2592 hole = hole == 0;
2593 }
2594 }
2595
2596 /*-
2597 * Convert text->integer.
2598 *
2599 * Traditional tar formats (including POSIX) specify base-8 for
2600 * all of the standard numeric fields. This is a significant limitation
2601 * in practice:
2602 * = file size is limited to 8GB
2603 * = rdevmajor and rdevminor are limited to 21 bits
2604 * = uid/gid are limited to 21 bits
2605 *
2606 * There are two workarounds for this:
2607 * = pax extended headers, which use variable-length string fields
2608 * = GNU tar and STAR both allow either base-8 or base-256 in
2609 * most fields. The high bit is set to indicate base-256.
2610 *
2611 * On read, this implementation supports both extensions.
2612 */
2613 static int64_t
tar_atol(const char * p,size_t char_cnt)2614 tar_atol(const char *p, size_t char_cnt)
2615 {
2616 /*
2617 * Technically, GNU tar considers a field to be in base-256
2618 * only if the first byte is 0xff or 0x80.
2619 */
2620 if (*p & 0x80)
2621 return (tar_atol256(p, char_cnt));
2622 return (tar_atol8(p, char_cnt));
2623 }
2624
2625 /*
2626 * Note that this implementation does not (and should not!) obey
2627 * locale settings; you cannot simply substitute strtol here, since
2628 * it does obey locale.
2629 */
2630 static int64_t
tar_atol_base_n(const char * p,size_t char_cnt,int base)2631 tar_atol_base_n(const char *p, size_t char_cnt, int base)
2632 {
2633 int64_t l, maxval, limit, last_digit_limit;
2634 int digit, sign;
2635
2636 maxval = INT64_MAX;
2637 limit = INT64_MAX / base;
2638 last_digit_limit = INT64_MAX % base;
2639
2640 /* the pointer will not be dereferenced if char_cnt is zero
2641 * due to the way the && operator is evaluated.
2642 */
2643 while (char_cnt != 0 && (*p == ' ' || *p == '\t')) {
2644 p++;
2645 char_cnt--;
2646 }
2647
2648 sign = 1;
2649 if (char_cnt != 0 && *p == '-') {
2650 sign = -1;
2651 p++;
2652 char_cnt--;
2653
2654 maxval = INT64_MIN;
2655 limit = -(INT64_MIN / base);
2656 last_digit_limit = -(INT64_MIN % base);
2657 }
2658
2659 l = 0;
2660 if (char_cnt != 0) {
2661 digit = *p - '0';
2662 while (digit >= 0 && digit < base && char_cnt != 0) {
2663 if (l>limit || (l == limit && digit >= last_digit_limit)) {
2664 return maxval; /* Truncate on overflow. */
2665 }
2666 l = (l * base) + digit;
2667 digit = *++p - '0';
2668 char_cnt--;
2669 }
2670 }
2671 return (sign < 0) ? -l : l;
2672 }
2673
2674 static int64_t
tar_atol8(const char * p,size_t char_cnt)2675 tar_atol8(const char *p, size_t char_cnt)
2676 {
2677 return tar_atol_base_n(p, char_cnt, 8);
2678 }
2679
2680 static int64_t
tar_atol10(const char * p,size_t char_cnt)2681 tar_atol10(const char *p, size_t char_cnt)
2682 {
2683 return tar_atol_base_n(p, char_cnt, 10);
2684 }
2685
2686 /*
2687 * Parse a base-256 integer. This is just a variable-length
2688 * twos-complement signed binary value in big-endian order, except
2689 * that the high-order bit is ignored. The values here can be up to
2690 * 12 bytes, so we need to be careful about overflowing 64-bit
2691 * (8-byte) integers.
2692 *
2693 * This code unashamedly assumes that the local machine uses 8-bit
2694 * bytes and twos-complement arithmetic.
2695 */
2696 static int64_t
tar_atol256(const char * _p,size_t char_cnt)2697 tar_atol256(const char *_p, size_t char_cnt)
2698 {
2699 uint64_t l;
2700 const unsigned char *p = (const unsigned char *)_p;
2701 unsigned char c, neg;
2702
2703 /* Extend 7-bit 2s-comp to 8-bit 2s-comp, decide sign. */
2704 c = *p;
2705 if (c & 0x40) {
2706 neg = 0xff;
2707 c |= 0x80;
2708 l = ~ARCHIVE_LITERAL_ULL(0);
2709 } else {
2710 neg = 0;
2711 c &= 0x7f;
2712 l = 0;
2713 }
2714
2715 /* If more than 8 bytes, check that we can ignore
2716 * high-order bits without overflow. */
2717 while (char_cnt > sizeof(int64_t)) {
2718 --char_cnt;
2719 if (c != neg)
2720 return neg ? INT64_MIN : INT64_MAX;
2721 c = *++p;
2722 }
2723
2724 /* c is first byte that fits; if sign mismatch, return overflow */
2725 if ((c ^ neg) & 0x80) {
2726 return neg ? INT64_MIN : INT64_MAX;
2727 }
2728
2729 /* Accumulate remaining bytes. */
2730 while (--char_cnt > 0) {
2731 l = (l << 8) | c;
2732 c = *++p;
2733 }
2734 l = (l << 8) | c;
2735 /* Return signed twos-complement value. */
2736 return (int64_t)(l);
2737 }
2738
2739 /*
2740 * Returns length of line (including trailing newline)
2741 * or negative on error. 'start' argument is updated to
2742 * point to first character of line. This avoids copying
2743 * when possible.
2744 */
2745 static ssize_t
readline(struct archive_read * a,struct tar * tar,const char ** start,ssize_t limit,size_t * unconsumed)2746 readline(struct archive_read *a, struct tar *tar, const char **start,
2747 ssize_t limit, size_t *unconsumed)
2748 {
2749 ssize_t bytes_read;
2750 ssize_t total_size = 0;
2751 const void *t;
2752 const char *s;
2753 void *p;
2754
2755 tar_flush_unconsumed(a, unconsumed);
2756
2757 t = __archive_read_ahead(a, 1, &bytes_read);
2758 if (bytes_read <= 0)
2759 return (ARCHIVE_FATAL);
2760 s = t; /* Start of line? */
2761 p = memchr(t, '\n', bytes_read);
2762 /* If we found '\n' in the read buffer, return pointer to that. */
2763 if (p != NULL) {
2764 bytes_read = 1 + ((const char *)p) - s;
2765 if (bytes_read > limit) {
2766 archive_set_error(&a->archive,
2767 ARCHIVE_ERRNO_FILE_FORMAT,
2768 "Line too long");
2769 return (ARCHIVE_FATAL);
2770 }
2771 *unconsumed = bytes_read;
2772 *start = s;
2773 return (bytes_read);
2774 }
2775 *unconsumed = bytes_read;
2776 /* Otherwise, we need to accumulate in a line buffer. */
2777 for (;;) {
2778 if (total_size + bytes_read > limit) {
2779 archive_set_error(&a->archive,
2780 ARCHIVE_ERRNO_FILE_FORMAT,
2781 "Line too long");
2782 return (ARCHIVE_FATAL);
2783 }
2784 if (archive_string_ensure(&tar->line, total_size + bytes_read) == NULL) {
2785 archive_set_error(&a->archive, ENOMEM,
2786 "Can't allocate working buffer");
2787 return (ARCHIVE_FATAL);
2788 }
2789 memcpy(tar->line.s + total_size, t, bytes_read);
2790 tar_flush_unconsumed(a, unconsumed);
2791 total_size += bytes_read;
2792 /* If we found '\n', clean up and return. */
2793 if (p != NULL) {
2794 *start = tar->line.s;
2795 return (total_size);
2796 }
2797 /* Read some more. */
2798 t = __archive_read_ahead(a, 1, &bytes_read);
2799 if (bytes_read <= 0)
2800 return (ARCHIVE_FATAL);
2801 s = t; /* Start of line? */
2802 p = memchr(t, '\n', bytes_read);
2803 /* If we found '\n', trim the read. */
2804 if (p != NULL) {
2805 bytes_read = 1 + ((const char *)p) - s;
2806 }
2807 *unconsumed = bytes_read;
2808 }
2809 }
2810
2811 /*
2812 * base64_decode - Base64 decode
2813 *
2814 * This accepts most variations of base-64 encoding, including:
2815 * * with or without line breaks
2816 * * with or without the final group padded with '=' or '_' characters
2817 * (The most economical Base-64 variant does not pad the last group and
2818 * omits line breaks; RFC1341 used for MIME requires both.)
2819 */
2820 static char *
base64_decode(const char * s,size_t len,size_t * out_len)2821 base64_decode(const char *s, size_t len, size_t *out_len)
2822 {
2823 static const unsigned char digits[64] = {
2824 'A','B','C','D','E','F','G','H','I','J','K','L','M','N',
2825 'O','P','Q','R','S','T','U','V','W','X','Y','Z','a','b',
2826 'c','d','e','f','g','h','i','j','k','l','m','n','o','p',
2827 'q','r','s','t','u','v','w','x','y','z','0','1','2','3',
2828 '4','5','6','7','8','9','+','/' };
2829 static unsigned char decode_table[128];
2830 char *out, *d;
2831 const unsigned char *src = (const unsigned char *)s;
2832
2833 /* If the decode table is not yet initialized, prepare it. */
2834 if (decode_table[digits[1]] != 1) {
2835 unsigned i;
2836 memset(decode_table, 0xff, sizeof(decode_table));
2837 for (i = 0; i < sizeof(digits); i++)
2838 decode_table[digits[i]] = i;
2839 }
2840
2841 /* Allocate enough space to hold the entire output. */
2842 /* Note that we may not use all of this... */
2843 out = (char *)malloc(len - len / 4 + 1);
2844 if (out == NULL) {
2845 *out_len = 0;
2846 return (NULL);
2847 }
2848 d = out;
2849
2850 while (len > 0) {
2851 /* Collect the next group of (up to) four characters. */
2852 int v = 0;
2853 int group_size = 0;
2854 while (group_size < 4 && len > 0) {
2855 /* '=' or '_' padding indicates final group. */
2856 if (*src == '=' || *src == '_') {
2857 len = 0;
2858 break;
2859 }
2860 /* Skip illegal characters (including line breaks) */
2861 if (*src > 127 || *src < 32
2862 || decode_table[*src] == 0xff) {
2863 len--;
2864 src++;
2865 continue;
2866 }
2867 v <<= 6;
2868 v |= decode_table[*src++];
2869 len --;
2870 group_size++;
2871 }
2872 /* Align a short group properly. */
2873 v <<= 6 * (4 - group_size);
2874 /* Unpack the group we just collected. */
2875 switch (group_size) {
2876 case 4: d[2] = v & 0xff;
2877 /* FALLTHROUGH */
2878 case 3: d[1] = (v >> 8) & 0xff;
2879 /* FALLTHROUGH */
2880 case 2: d[0] = (v >> 16) & 0xff;
2881 break;
2882 case 1: /* this is invalid! */
2883 break;
2884 }
2885 d += group_size * 3 / 4;
2886 }
2887
2888 *out_len = d - out;
2889 return (out);
2890 }
2891
2892 static char *
url_decode(const char * in)2893 url_decode(const char *in)
2894 {
2895 char *out, *d;
2896 const char *s;
2897
2898 out = (char *)malloc(strlen(in) + 1);
2899 if (out == NULL)
2900 return (NULL);
2901 for (s = in, d = out; *s != '\0'; ) {
2902 if (s[0] == '%' && s[1] != '\0' && s[2] != '\0') {
2903 /* Try to convert % escape */
2904 int digit1 = tohex(s[1]);
2905 int digit2 = tohex(s[2]);
2906 if (digit1 >= 0 && digit2 >= 0) {
2907 /* Looks good, consume three chars */
2908 s += 3;
2909 /* Convert output */
2910 *d++ = ((digit1 << 4) | digit2);
2911 continue;
2912 }
2913 /* Else fall through and treat '%' as normal char */
2914 }
2915 *d++ = *s++;
2916 }
2917 *d = '\0';
2918 return (out);
2919 }
2920
2921 static int
tohex(int c)2922 tohex(int c)
2923 {
2924 if (c >= '0' && c <= '9')
2925 return (c - '0');
2926 else if (c >= 'A' && c <= 'F')
2927 return (c - 'A' + 10);
2928 else if (c >= 'a' && c <= 'f')
2929 return (c - 'a' + 10);
2930 else
2931 return (-1);
2932 }
2933