source: trunk/minix/commands/pax/tar.c@ 10

Last change on this file since 10 was 9, checked in by Mattia Monga, 13 years ago

Minix 3.1.2a

File size: 28.6 KB
Line 
1/*-
2 * Copyright (c) 1992 Keith Muller.
3 * Copyright (c) 1992, 1993
4 * The Regents of the University of California. All rights reserved.
5 *
6 * This code is derived from software contributed to Berkeley by
7 * Keith Muller of the University of California, San Diego.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#ifndef lint
35#if 0
36static char sccsid[] = "@(#)tar.c 8.2 (Berkeley) 4/18/94";
37#endif
38#endif /* not lint */
39
40#include <sys/types.h>
41#include <sys/time.h>
42#include <sys/stat.h>
43#include <string.h>
44#include <stdio.h>
45#include <unistd.h>
46#include <stdlib.h>
47#include "pax.h"
48#include "extern.h"
49#include "tar.h"
50
51/*
52 * Routines for reading, writing and header identify of various versions of tar
53 */
54
55static u_long tar_chksm(char *, int);
56static char *name_split(char *, int);
57static int ul_oct(u_long, char *, int, int);
58#ifndef NET2_STAT
59static int uqd_oct(u_quad_t, char *, int, int);
60#endif
61
62/*
63 * Routines common to all versions of tar
64 */
65
66static int tar_nodir; /* do not write dirs under old tar */
67
68/*
69 * tar_endwr()
70 * add the tar trailer of two null blocks
71 * Return:
72 * 0 if ok, -1 otherwise (what wr_skip returns)
73 */
74
75int
76tar_endwr(void)
77{
78 return(wr_skip((off_t)(NULLCNT*BLKMULT)));
79}
80
81/*
82 * tar_endrd()
83 * no cleanup needed here, just return size of trailer (for append)
84 * Return:
85 * size of trailer (2 * BLKMULT)
86 */
87
88off_t
89tar_endrd(void)
90{
91 return((off_t)(NULLCNT*BLKMULT));
92}
93
94/*
95 * tar_trail()
96 * Called to determine if a header block is a valid trailer. We are passed
97 * the block, the in_sync flag (which tells us we are in resync mode;
98 * looking for a valid header), and cnt (which starts at zero) which is
99 * used to count the number of empty blocks we have seen so far.
100 * Return:
101 * 0 if a valid trailer, -1 if not a valid trailer, or 1 if the block
102 * could never contain a header.
103 */
104
105int
106tar_trail(char *buf, int in_resync, int *cnt)
107{
108 int i;
109
110 /*
111 * look for all zero, trailer is two consecutive blocks of zero
112 */
113 for (i = 0; i < BLKMULT; ++i) {
114 if (buf[i] != '\0')
115 break;
116 }
117
118 /*
119 * if not all zero it is not a trailer, but MIGHT be a header.
120 */
121 if (i != BLKMULT)
122 return(-1);
123
124 /*
125 * When given a zero block, we must be careful!
126 * If we are not in resync mode, check for the trailer. Have to watch
127 * out that we do not mis-identify file data as the trailer, so we do
128 * NOT try to id a trailer during resync mode. During resync mode we
129 * might as well throw this block out since a valid header can NEVER be
130 * a block of all 0 (we must have a valid file name).
131 */
132 if (!in_resync && (++*cnt >= NULLCNT))
133 return(0);
134 return(1);
135}
136
137/*
138 * ul_oct()
139 * convert an unsigned long to an octal string. many oddball field
140 * termination characters are used by the various versions of tar in the
141 * different fields. term selects which kind to use. str is '0' padded
142 * at the front to len. we are unable to use only one format as many old
143 * tar readers are very cranky about this.
144 * Return:
145 * 0 if the number fit into the string, -1 otherwise
146 */
147
148static int
149ul_oct(u_long val, char *str, int len, int term)
150{
151 char *pt;
152
153 /*
154 * term selects the appropriate character(s) for the end of the string
155 */
156 pt = str + len - 1;
157 switch(term) {
158 case 3:
159 *pt-- = '\0';
160 break;
161 case 2:
162 *pt-- = ' ';
163 *pt-- = '\0';
164 break;
165 case 1:
166 *pt-- = ' ';
167 break;
168 case 0:
169 default:
170 *pt-- = '\0';
171 *pt-- = ' ';
172 break;
173 }
174
175 /*
176 * convert and blank pad if there is space
177 */
178 while (pt >= str) {
179 *pt-- = '0' + (char)(val & 0x7);
180 if ((val = val >> 3) == (u_long)0)
181 break;
182 }
183
184 while (pt >= str)
185 *pt-- = '0';
186 if (val != (u_long)0)
187 return(-1);
188 return(0);
189}
190
191#ifndef NET2_STAT
192/*
193 * uqd_oct()
194 * convert an u_quad_t to an octal string. one of many oddball field
195 * termination characters are used by the various versions of tar in the
196 * different fields. term selects which kind to use. str is '0' padded
197 * at the front to len. we are unable to use only one format as many old
198 * tar readers are very cranky about this.
199 * Return:
200 * 0 if the number fit into the string, -1 otherwise
201 */
202
203static int
204uqd_oct(u_quad_t val, char *str, int len, int term)
205{
206 char *pt;
207
208 /*
209 * term selects the appropriate character(s) for the end of the string
210 */
211 pt = str + len - 1;
212 switch(term) {
213 case 3:
214 *pt-- = '\0';
215 break;
216 case 2:
217 *pt-- = ' ';
218 *pt-- = '\0';
219 break;
220 case 1:
221 *pt-- = ' ';
222 break;
223 case 0:
224 default:
225 *pt-- = '\0';
226 *pt-- = ' ';
227 break;
228 }
229
230 /*
231 * convert and blank pad if there is space
232 */
233 while (pt >= str) {
234 *pt-- = '0' + (char)(val & 0x7);
235 if ((val = val >> 3) == 0)
236 break;
237 }
238
239 while (pt >= str)
240 *pt-- = '0';
241 if (val != (u_quad_t)0)
242 return(-1);
243 return(0);
244}
245#endif
246
247/*
248 * tar_chksm()
249 * calculate the checksum for a tar block counting the checksum field as
250 * all blanks (BLNKSUM is that value pre-calculated, the sum of 8 blanks).
251 * NOTE: we use len to short circuit summing 0's on write since we ALWAYS
252 * pad headers with 0.
253 * Return:
254 * unsigned long checksum
255 */
256
257static u_long
258tar_chksm(char *blk, int len)
259{
260 char *stop;
261 char *pt;
262 u_long chksm = BLNKSUM; /* initial value is checksum field sum */
263
264 /*
265 * add the part of the block before the checksum field
266 */
267 pt = blk;
268 stop = blk + CHK_OFFSET;
269 while (pt < stop)
270 chksm += (u_long)(*pt++ & 0xff);
271 /*
272 * move past the checksum field and keep going, spec counts the
273 * checksum field as the sum of 8 blanks (which is pre-computed as
274 * BLNKSUM).
275 * ASSUMED: len is greater than CHK_OFFSET. (len is where our 0 padding
276 * starts, no point in summing zero's)
277 */
278 pt += CHK_LEN;
279 stop = blk + len;
280 while (pt < stop)
281 chksm += (u_long)(*pt++ & 0xff);
282 return(chksm);
283}
284
285/*
286 * Routines for old BSD style tar (also made portable to sysV tar)
287 */
288
289/*
290 * tar_id()
291 * determine if a block given to us is a valid tar header (and not a USTAR
292 * header). We have to be on the lookout for those pesky blocks of all
293 * zero's.
294 * Return:
295 * 0 if a tar header, -1 otherwise
296 */
297
298int
299tar_id(char *blk, int size)
300{
301 HD_TAR *hd;
302 HD_USTAR *uhd;
303
304 if (size < BLKMULT)
305 return(-1);
306 hd = (HD_TAR *)blk;
307 uhd = (HD_USTAR *)blk;
308
309 /*
310 * check for block of zero's first, a simple and fast test, then make
311 * sure this is not a ustar header by looking for the ustar magic
312 * cookie. We should use TMAGLEN, but some USTAR archive programs are
313 * wrong and create archives missing the \0. Last we check the
314 * checksum. If this is ok we have to assume it is a valid header.
315 */
316 if (hd->name[0] == '\0')
317 return(-1);
318 if (strncmp(uhd->magic, TMAGIC, TMAGLEN - 1) == 0)
319 return(-1);
320 if (asc_ul(hd->chksum,sizeof(hd->chksum),OCT) != tar_chksm(blk,BLKMULT))
321 return(-1);
322 return(0);
323}
324
325/*
326 * tar_opt()
327 * handle tar format specific -o options
328 * Return:
329 * 0 if ok -1 otherwise
330 */
331
332int
333tar_opt(void)
334{
335 OPLIST *opt;
336
337 while ((opt = opt_next()) != NULL) {
338 if (strcmp(opt->name, TAR_OPTION) ||
339 strcmp(opt->value, TAR_NODIR)) {
340 paxwarn(1, "Unknown tar format -o option/value pair %s=%s",
341 opt->name, opt->value);
342 paxwarn(1,"%s=%s is the only supported tar format option",
343 TAR_OPTION, TAR_NODIR);
344 return(-1);
345 }
346
347 /*
348 * we only support one option, and only when writing
349 */
350 if ((act != APPND) && (act != ARCHIVE)) {
351 paxwarn(1, "%s=%s is only supported when writing.",
352 opt->name, opt->value);
353 return(-1);
354 }
355 tar_nodir = 1;
356 }
357 return(0);
358}
359
360
361/*
362 * tar_rd()
363 * extract the values out of block already determined to be a tar header.
364 * store the values in the ARCHD parameter.
365 * Return:
366 * 0
367 */
368
369int
370tar_rd(ARCHD *arcn, char *buf)
371{
372 HD_TAR *hd;
373 char *pt;
374
375 /*
376 * we only get proper sized buffers passed to us
377 */
378 if (tar_id(buf, BLKMULT) < 0)
379 return(-1);
380 arcn->org_name = arcn->name;
381 arcn->sb.st_nlink = 1;
382 arcn->pat = NULL;
383
384 /*
385 * copy out the name and values in the stat buffer
386 */
387 hd = (HD_TAR *)buf;
388 /*
389 * old tar format specifies the name always be null-terminated,
390 * but let's be robust to broken archives.
391 * the same applies to handling links below.
392 */
393 arcn->nlen = l_strncpy(arcn->name, hd->name,
394 MIN(sizeof(hd->name), sizeof(arcn->name)) - 1);
395 arcn->name[arcn->nlen] = '\0';
396 arcn->sb.st_mode = (mode_t)(asc_ul(hd->mode,sizeof(hd->mode),OCT) &
397 0xfff);
398 arcn->sb.st_uid = (uid_t)asc_ul(hd->uid, sizeof(hd->uid), OCT);
399 arcn->sb.st_gid = (gid_t)asc_ul(hd->gid, sizeof(hd->gid), OCT);
400#ifdef NET2_STAT
401 arcn->sb.st_size = (off_t)asc_ul(hd->size, sizeof(hd->size), OCT);
402 arcn->sb.st_mtime = (time_t)asc_ul(hd->mtime, sizeof(hd->mtime), OCT);
403#else
404 arcn->sb.st_size = (off_t)asc_uqd(hd->size, sizeof(hd->size), OCT);
405 arcn->sb.st_mtime = (time_t)asc_uqd(hd->mtime, sizeof(hd->mtime), OCT);
406#endif
407 arcn->sb.st_ctime = arcn->sb.st_atime = arcn->sb.st_mtime;
408
409 /*
410 * have to look at the last character, it may be a '/' and that is used
411 * to encode this as a directory
412 */
413 pt = &(arcn->name[arcn->nlen - 1]);
414 arcn->pad = 0;
415 arcn->skip = 0;
416 switch(hd->linkflag) {
417 case SYMTYPE:
418 /*
419 * symbolic link, need to get the link name and set the type in
420 * the st_mode so -v printing will look correct.
421 */
422 arcn->type = PAX_SLK;
423 arcn->ln_nlen = l_strncpy(arcn->ln_name, hd->linkname,
424 MIN(sizeof(hd->linkname), sizeof(arcn->ln_name)) - 1);
425 arcn->ln_name[arcn->ln_nlen] = '\0';
426 arcn->sb.st_mode |= S_IFLNK;
427 break;
428 case LNKTYPE:
429 /*
430 * hard link, need to get the link name, set the type in the
431 * st_mode and st_nlink so -v printing will look better.
432 */
433 arcn->type = PAX_HLK;
434 arcn->sb.st_nlink = 2;
435 arcn->ln_nlen = l_strncpy(arcn->ln_name, hd->linkname,
436 MIN(sizeof(hd->linkname), sizeof(arcn->ln_name)) - 1);
437 arcn->ln_name[arcn->ln_nlen] = '\0';
438
439 /*
440 * no idea of what type this thing really points at, but
441 * we set something for printing only.
442 */
443 arcn->sb.st_mode |= S_IFREG;
444 break;
445 case DIRTYPE:
446 /*
447 * It is a directory, set the mode for -v printing
448 */
449 arcn->type = PAX_DIR;
450 arcn->sb.st_mode |= S_IFDIR;
451 arcn->sb.st_nlink = 2;
452 arcn->ln_name[0] = '\0';
453 arcn->ln_nlen = 0;
454 break;
455 case AREGTYPE:
456 case REGTYPE:
457 default:
458 /*
459 * If we have a trailing / this is a directory and NOT a file.
460 */
461 arcn->ln_name[0] = '\0';
462 arcn->ln_nlen = 0;
463 if (*pt == '/') {
464 /*
465 * it is a directory, set the mode for -v printing
466 */
467 arcn->type = PAX_DIR;
468 arcn->sb.st_mode |= S_IFDIR;
469 arcn->sb.st_nlink = 2;
470 } else {
471 /*
472 * have a file that will be followed by data. Set the
473 * skip value to the size field and calculate the size
474 * of the padding.
475 */
476 arcn->type = PAX_REG;
477 arcn->sb.st_mode |= S_IFREG;
478 arcn->pad = TAR_PAD(arcn->sb.st_size);
479 arcn->skip = arcn->sb.st_size;
480 }
481 break;
482 }
483
484 /*
485 * strip off any trailing slash.
486 */
487 if (*pt == '/') {
488 *pt = '\0';
489 --arcn->nlen;
490 }
491 return(0);
492}
493
494/*
495 * tar_wr()
496 * write a tar header for the file specified in the ARCHD to the archive.
497 * Have to check for file types that cannot be stored and file names that
498 * are too long. Be careful of the term (last arg) to ul_oct, each field
499 * of tar has it own spec for the termination character(s).
500 * ASSUMED: space after header in header block is zero filled
501 * Return:
502 * 0 if file has data to be written after the header, 1 if file has NO
503 * data to write after the header, -1 if archive write failed
504 */
505
506int
507tar_wr(ARCHD *arcn)
508{
509 HD_TAR *hd;
510 int len;
511 char hdblk[sizeof(HD_TAR)];
512
513 /*
514 * check for those file system types which tar cannot store
515 */
516 switch(arcn->type) {
517 case PAX_DIR:
518 /*
519 * user asked that dirs not be written to the archive
520 */
521 if (tar_nodir)
522 return(1);
523 break;
524 case PAX_CHR:
525 paxwarn(1, "Tar cannot archive a character device %s",
526 arcn->org_name);
527 return(1);
528 case PAX_BLK:
529 paxwarn(1, "Tar cannot archive a block device %s", arcn->org_name);
530 return(1);
531 case PAX_SCK:
532 paxwarn(1, "Tar cannot archive a socket %s", arcn->org_name);
533 return(1);
534 case PAX_FIF:
535 paxwarn(1, "Tar cannot archive a fifo %s", arcn->org_name);
536 return(1);
537 case PAX_SLK:
538 case PAX_HLK:
539 case PAX_HRG:
540 if (arcn->ln_nlen >= (int)sizeof(hd->linkname)) {
541 paxwarn(1,"Link name too long for tar %s", arcn->ln_name);
542 return(1);
543 }
544 break;
545 case PAX_REG:
546 case PAX_CTG:
547 default:
548 break;
549 }
550
551 /*
552 * check file name len, remember extra char for dirs (the / at the end)
553 */
554 len = arcn->nlen;
555 if (arcn->type == PAX_DIR)
556 ++len;
557 if (len >= (int)sizeof(hd->name)) {
558 paxwarn(1, "File name too long for tar %s", arcn->name);
559 return(1);
560 }
561
562 /*
563 * copy the data out of the ARCHD into the tar header based on the type
564 * of the file. Remember many tar readers want the unused fields to be
565 * padded with zero. We set the linkflag field (type), the linkname
566 * (or zero if not used),the size, and set the padding (if any) to be
567 * added after the file data (0 for all other types, as they only have
568 * a header)
569 */
570 hd = (HD_TAR *)hdblk;
571 l_strncpy(hd->name, arcn->name, sizeof(hd->name) - 1);
572 hd->name[sizeof(hd->name) - 1] = '\0';
573 arcn->pad = 0;
574
575 if (arcn->type == PAX_DIR) {
576 /*
577 * directories are the same as files, except have a filename
578 * that ends with a /, we add the slash here. No data follows,
579 * dirs, so no pad.
580 */
581 hd->linkflag = AREGTYPE;
582 memset(hd->linkname, 0, sizeof(hd->linkname));
583 hd->name[len-1] = '/';
584 if (ul_oct((u_long)0L, hd->size, sizeof(hd->size), 1))
585 goto out;
586 } else if (arcn->type == PAX_SLK) {
587 /*
588 * no data follows this file, so no pad
589 */
590 hd->linkflag = SYMTYPE;
591 l_strncpy(hd->linkname,arcn->ln_name, sizeof(hd->linkname) - 1);
592 hd->linkname[sizeof(hd->linkname) - 1] = '\0';
593 if (ul_oct((u_long)0L, hd->size, sizeof(hd->size), 1))
594 goto out;
595 } else if ((arcn->type == PAX_HLK) || (arcn->type == PAX_HRG)) {
596 /*
597 * no data follows this file, so no pad
598 */
599 hd->linkflag = LNKTYPE;
600 l_strncpy(hd->linkname,arcn->ln_name, sizeof(hd->linkname) - 1);
601 hd->linkname[sizeof(hd->linkname) - 1] = '\0';
602 if (ul_oct((u_long)0L, hd->size, sizeof(hd->size), 1))
603 goto out;
604 } else {
605 /*
606 * data follows this file, so set the pad
607 */
608 hd->linkflag = AREGTYPE;
609 memset(hd->linkname, 0, sizeof(hd->linkname));
610# ifdef NET2_STAT
611 if (ul_oct((u_long)arcn->sb.st_size, hd->size,
612 sizeof(hd->size), 1)) {
613# else
614 if (uqd_oct((u_quad_t)arcn->sb.st_size, hd->size,
615 sizeof(hd->size), 1)) {
616# endif
617 paxwarn(1,"File is too large for tar %s", arcn->org_name);
618 return(1);
619 }
620 arcn->pad = TAR_PAD(arcn->sb.st_size);
621 }
622
623 /*
624 * copy those fields that are independent of the type
625 */
626 if (ul_oct((u_long)arcn->sb.st_mode, hd->mode, sizeof(hd->mode), 0) ||
627 ul_oct((u_long)arcn->sb.st_uid, hd->uid, sizeof(hd->uid), 0) ||
628 ul_oct((u_long)arcn->sb.st_gid, hd->gid, sizeof(hd->gid), 0) ||
629 ul_oct((u_long)arcn->sb.st_mtime, hd->mtime, sizeof(hd->mtime), 1))
630 goto out;
631
632 /*
633 * calculate and add the checksum, then write the header. A return of
634 * 0 tells the caller to now write the file data, 1 says no data needs
635 * to be written
636 */
637 if (ul_oct(tar_chksm(hdblk, sizeof(HD_TAR)), hd->chksum,
638 sizeof(hd->chksum), 3))
639 goto out;
640 if (wr_rdbuf(hdblk, sizeof(HD_TAR)) < 0)
641 return(-1);
642 if (wr_skip((off_t)(BLKMULT - sizeof(HD_TAR))) < 0)
643 return(-1);
644 if ((arcn->type == PAX_CTG) || (arcn->type == PAX_REG))
645 return(0);
646 return(1);
647
648 out:
649 /*
650 * header field is out of range
651 */
652 paxwarn(1, "Tar header field is too small for %s", arcn->org_name);
653 return(1);
654}
655
656/*
657 * Routines for POSIX ustar
658 */
659
660/*
661 * ustar_strd()
662 * initialization for ustar read
663 * Return:
664 * 0 if ok, -1 otherwise
665 */
666
667int
668ustar_strd(void)
669{
670 if ((usrtb_start() < 0) || (grptb_start() < 0))
671 return(-1);
672 return(0);
673}
674
675/*
676 * ustar_stwr()
677 * initialization for ustar write
678 * Return:
679 * 0 if ok, -1 otherwise
680 */
681
682int
683ustar_stwr(void)
684{
685 if ((uidtb_start() < 0) || (gidtb_start() < 0))
686 return(-1);
687 return(0);
688}
689
690/*
691 * ustar_id()
692 * determine if a block given to us is a valid ustar header. We have to
693 * be on the lookout for those pesky blocks of all zero's
694 * Return:
695 * 0 if a ustar header, -1 otherwise
696 */
697
698int
699ustar_id(char *blk, int size)
700{
701 HD_USTAR *hd;
702
703 if (size < BLKMULT)
704 return(-1);
705 hd = (HD_USTAR *)blk;
706
707 /*
708 * check for block of zero's first, a simple and fast test then check
709 * ustar magic cookie. We should use TMAGLEN, but some USTAR archive
710 * programs are fouled up and create archives missing the \0. Last we
711 * check the checksum. If ok we have to assume it is a valid header.
712 */
713 if (hd->name[0] == '\0')
714 return(-1);
715 if (strncmp(hd->magic, TMAGIC, TMAGLEN - 1) != 0)
716 return(-1);
717 if (asc_ul(hd->chksum,sizeof(hd->chksum),OCT) != tar_chksm(blk,BLKMULT))
718 return(-1);
719 return(0);
720}
721
722/*
723 * ustar_rd()
724 * extract the values out of block already determined to be a ustar header.
725 * store the values in the ARCHD parameter.
726 * Return:
727 * 0
728 */
729
730int
731ustar_rd(ARCHD *arcn, char *buf)
732{
733 HD_USTAR *hd;
734 char *dest;
735 int cnt = 0;
736 dev_t devmajor;
737 dev_t devminor;
738
739 /*
740 * we only get proper sized buffers
741 */
742 if (ustar_id(buf, BLKMULT) < 0)
743 return(-1);
744 arcn->org_name = arcn->name;
745 arcn->sb.st_nlink = 1;
746 arcn->pat = NULL;
747 arcn->nlen = 0;
748 hd = (HD_USTAR *)buf;
749
750 /*
751 * see if the filename is split into two parts. if, so joint the parts.
752 * we copy the prefix first and add a / between the prefix and name.
753 */
754 dest = arcn->name;
755 if (*(hd->prefix) != '\0') {
756 cnt = l_strncpy(dest, hd->prefix,
757 MIN(sizeof(hd->prefix), sizeof(arcn->name) - 2));
758 dest += cnt;
759 *dest++ = '/';
760 cnt++;
761 }
762 /*
763 * ustar format specifies the name may be unterminated
764 * if it fills the entire field. this also applies to
765 * the prefix and the linkname.
766 */
767 arcn->nlen = cnt + l_strncpy(dest, hd->name,
768 MIN(sizeof(hd->name), sizeof(arcn->name) - cnt - 1));
769 arcn->name[arcn->nlen] = '\0';
770
771 /*
772 * follow the spec to the letter. we should only have mode bits, strip
773 * off all other crud we may be passed.
774 */
775 arcn->sb.st_mode = (mode_t)(asc_ul(hd->mode, sizeof(hd->mode), OCT) &
776 0xfff);
777#ifdef NET2_STAT
778 arcn->sb.st_size = (off_t)asc_ul(hd->size, sizeof(hd->size), OCT);
779 arcn->sb.st_mtime = (time_t)asc_ul(hd->mtime, sizeof(hd->mtime), OCT);
780#else
781 arcn->sb.st_size = (off_t)asc_uqd(hd->size, sizeof(hd->size), OCT);
782 arcn->sb.st_mtime = (time_t)asc_uqd(hd->mtime, sizeof(hd->mtime), OCT);
783#endif
784 arcn->sb.st_ctime = arcn->sb.st_atime = arcn->sb.st_mtime;
785
786 /*
787 * If we can find the ascii names for gname and uname in the password
788 * and group files we will use the uid's and gid they bind. Otherwise
789 * we use the uid and gid values stored in the header. (This is what
790 * the POSIX spec wants).
791 */
792 hd->gname[sizeof(hd->gname) - 1] = '\0';
793 if (gid_name((char *) hd->gname, (gid_t *) &(arcn->sb.st_gid)) < 0)
794 arcn->sb.st_gid = (gid_t)asc_ul(hd->gid, sizeof(hd->gid), OCT);
795 hd->uname[sizeof(hd->uname) - 1] = '\0';
796 if (uid_name(hd->uname, &(arcn->sb.st_uid)) < 0)
797 arcn->sb.st_uid = (uid_t)asc_ul(hd->uid, sizeof(hd->uid), OCT);
798
799 /*
800 * set the defaults, these may be changed depending on the file type
801 */
802 arcn->ln_name[0] = '\0';
803 arcn->ln_nlen = 0;
804 arcn->pad = 0;
805 arcn->skip = 0;
806 arcn->sb.st_rdev = (dev_t)0;
807
808 /*
809 * set the mode and PAX type according to the typeflag in the header
810 */
811 switch(hd->typeflag) {
812 case FIFOTYPE:
813 arcn->type = PAX_FIF;
814 arcn->sb.st_mode |= S_IFIFO;
815 break;
816 case DIRTYPE:
817 arcn->type = PAX_DIR;
818 arcn->sb.st_mode |= S_IFDIR;
819 arcn->sb.st_nlink = 2;
820
821 /*
822 * Some programs that create ustar archives append a '/'
823 * to the pathname for directories. This clearly violates
824 * ustar specs, but we will silently strip it off anyway.
825 */
826 if (arcn->name[arcn->nlen - 1] == '/')
827 arcn->name[--arcn->nlen] = '\0';
828 break;
829 case BLKTYPE:
830 case CHRTYPE:
831 /*
832 * this type requires the rdev field to be set.
833 */
834 if (hd->typeflag == BLKTYPE) {
835 arcn->type = PAX_BLK;
836 arcn->sb.st_mode |= S_IFBLK;
837 } else {
838 arcn->type = PAX_CHR;
839 arcn->sb.st_mode |= S_IFCHR;
840 }
841 devmajor = (dev_t)asc_ul(hd->devmajor,sizeof(hd->devmajor),OCT);
842 devminor = (dev_t)asc_ul(hd->devminor,sizeof(hd->devminor),OCT);
843 arcn->sb.st_rdev = TODEV(devmajor, devminor);
844 break;
845 case SYMTYPE:
846 case LNKTYPE:
847 if (hd->typeflag == SYMTYPE) {
848 arcn->type = PAX_SLK;
849 arcn->sb.st_mode |= S_IFLNK;
850 } else {
851 arcn->type = PAX_HLK;
852 /*
853 * so printing looks better
854 */
855 arcn->sb.st_mode |= S_IFREG;
856 arcn->sb.st_nlink = 2;
857 }
858 /*
859 * copy the link name
860 */
861 arcn->ln_nlen = l_strncpy(arcn->ln_name, hd->linkname,
862 MIN(sizeof(hd->linkname), sizeof(arcn->ln_name) - 1));
863 arcn->ln_name[arcn->ln_nlen] = '\0';
864 break;
865 case CONTTYPE:
866 case AREGTYPE:
867 case REGTYPE:
868 default:
869 /*
870 * these types have file data that follows. Set the skip and
871 * pad fields.
872 */
873 arcn->type = PAX_REG;
874 arcn->pad = TAR_PAD(arcn->sb.st_size);
875 arcn->skip = arcn->sb.st_size;
876 arcn->sb.st_mode |= S_IFREG;
877 break;
878 }
879 return(0);
880}
881
882/*
883 * ustar_wr()
884 * write a ustar header for the file specified in the ARCHD to the archive
885 * Have to check for file types that cannot be stored and file names that
886 * are too long. Be careful of the term (last arg) to ul_oct, we only use
887 * '\0' for the termination character (this is different than picky tar)
888 * ASSUMED: space after header in header block is zero filled
889 * Return:
890 * 0 if file has data to be written after the header, 1 if file has NO
891 * data to write after the header, -1 if archive write failed
892 */
893
894int
895ustar_wr(ARCHD *arcn)
896{
897 HD_USTAR *hd;
898 char *pt;
899 char hdblk[sizeof(HD_USTAR)];
900
901 /*
902 * check for those file system types ustar cannot store
903 */
904 if (arcn->type == PAX_SCK) {
905 paxwarn(1, "Ustar cannot archive a socket %s", arcn->org_name);
906 return(1);
907 }
908
909 /*
910 * check the length of the linkname
911 */
912 if (((arcn->type == PAX_SLK) || (arcn->type == PAX_HLK) ||
913 (arcn->type == PAX_HRG)) &&
914 (arcn->ln_nlen > (int)sizeof(hd->linkname))) {
915 paxwarn(1, "Link name too long for ustar %s", arcn->ln_name);
916 return(1);
917 }
918
919 /*
920 * split the path name into prefix and name fields (if needed). if
921 * pt != arcn->name, the name has to be split
922 */
923 if ((pt = name_split(arcn->name, arcn->nlen)) == NULL) {
924 paxwarn(1, "File name too long for ustar %s", arcn->name);
925 return(1);
926 }
927 hd = (HD_USTAR *)hdblk;
928 arcn->pad = 0L;
929
930 /*
931 * split the name, or zero out the prefix
932 */
933 if (pt != arcn->name) {
934 /*
935 * name was split, pt points at the / where the split is to
936 * occur, we remove the / and copy the first part to the prefix
937 */
938 *pt = '\0';
939 l_strncpy(hd->prefix, arcn->name, sizeof(hd->prefix));
940 *pt++ = '/';
941 } else
942 memset(hd->prefix, 0, sizeof(hd->prefix));
943
944 /*
945 * copy the name part. this may be the whole path or the part after
946 * the prefix. both the name and prefix may fill the entire field.
947 */
948 l_strncpy(hd->name, pt, sizeof(hd->name));
949
950 /*
951 * set the fields in the header that are type dependent
952 */
953 switch(arcn->type) {
954 case PAX_DIR:
955 hd->typeflag = DIRTYPE;
956 memset(hd->linkname, 0, sizeof(hd->linkname));
957 memset(hd->devmajor, 0, sizeof(hd->devmajor));
958 memset(hd->devminor, 0, sizeof(hd->devminor));
959 if (ul_oct((u_long)0L, hd->size, sizeof(hd->size), 3))
960 goto out;
961 break;
962 case PAX_CHR:
963 case PAX_BLK:
964 if (arcn->type == PAX_CHR)
965 hd->typeflag = CHRTYPE;
966 else
967 hd->typeflag = BLKTYPE;
968 memset(hd->linkname, 0, sizeof(hd->linkname));
969 if (ul_oct((u_long)major(arcn->sb.st_rdev), hd->devmajor,
970 sizeof(hd->devmajor), 3) ||
971 ul_oct((u_long)minor(arcn->sb.st_rdev), hd->devminor,
972 sizeof(hd->devminor), 3) ||
973 ul_oct((u_long)0L, hd->size, sizeof(hd->size), 3))
974 goto out;
975 break;
976 case PAX_FIF:
977 hd->typeflag = FIFOTYPE;
978 memset(hd->linkname, 0, sizeof(hd->linkname));
979 memset(hd->devmajor, 0, sizeof(hd->devmajor));
980 memset(hd->devminor, 0, sizeof(hd->devminor));
981 if (ul_oct((u_long)0L, hd->size, sizeof(hd->size), 3))
982 goto out;
983 break;
984 case PAX_SLK:
985 case PAX_HLK:
986 case PAX_HRG:
987 if (arcn->type == PAX_SLK)
988 hd->typeflag = SYMTYPE;
989 else
990 hd->typeflag = LNKTYPE;
991 /* the link name may occupy the entire field in ustar */
992 l_strncpy(hd->linkname,arcn->ln_name, sizeof(hd->linkname));
993 memset(hd->devmajor, 0, sizeof(hd->devmajor));
994 memset(hd->devminor, 0, sizeof(hd->devminor));
995 if (ul_oct((u_long)0L, hd->size, sizeof(hd->size), 3))
996 goto out;
997 break;
998 case PAX_REG:
999 case PAX_CTG:
1000 default:
1001 /*
1002 * file data with this type, set the padding
1003 */
1004 if (arcn->type == PAX_CTG)
1005 hd->typeflag = CONTTYPE;
1006 else
1007 hd->typeflag = REGTYPE;
1008 memset(hd->linkname, 0, sizeof(hd->linkname));
1009 memset(hd->devmajor, 0, sizeof(hd->devmajor));
1010 memset(hd->devminor, 0, sizeof(hd->devminor));
1011 arcn->pad = TAR_PAD(arcn->sb.st_size);
1012# ifdef NET2_STAT
1013 if (ul_oct((u_long)arcn->sb.st_size, hd->size,
1014 sizeof(hd->size), 3)) {
1015# else
1016 if (uqd_oct((u_quad_t)arcn->sb.st_size, hd->size,
1017 sizeof(hd->size), 3)) {
1018# endif
1019 paxwarn(1,"File is too long for ustar %s",arcn->org_name);
1020 return(1);
1021 }
1022 break;
1023 }
1024
1025 l_strncpy(hd->magic, TMAGIC, TMAGLEN);
1026 l_strncpy(hd->version, TVERSION, TVERSLEN);
1027
1028 /*
1029 * set the remaining fields. Some versions want all 16 bits of mode
1030 * we better humor them (they really do not meet spec though)....
1031 */
1032 if (ul_oct((u_long)arcn->sb.st_mode, hd->mode, sizeof(hd->mode), 3) ||
1033 ul_oct((u_long)arcn->sb.st_uid, hd->uid, sizeof(hd->uid), 3) ||
1034 ul_oct((u_long)arcn->sb.st_gid, hd->gid, sizeof(hd->gid), 3) ||
1035 ul_oct((u_long)arcn->sb.st_mtime,hd->mtime,sizeof(hd->mtime),3))
1036 goto out;
1037 l_strncpy(hd->uname,name_uid(arcn->sb.st_uid, 0),sizeof(hd->uname));
1038 l_strncpy(hd->gname,name_gid(arcn->sb.st_gid, 0),sizeof(hd->gname));
1039
1040 /*
1041 * calculate and store the checksum write the header to the archive
1042 * return 0 tells the caller to now write the file data, 1 says no data
1043 * needs to be written
1044 */
1045 if (ul_oct(tar_chksm(hdblk, sizeof(HD_USTAR)), hd->chksum,
1046 sizeof(hd->chksum), 3))
1047 goto out;
1048 if (wr_rdbuf(hdblk, sizeof(HD_USTAR)) < 0)
1049 return(-1);
1050 if (wr_skip((off_t)(BLKMULT - sizeof(HD_USTAR))) < 0)
1051 return(-1);
1052 if ((arcn->type == PAX_CTG) || (arcn->type == PAX_REG))
1053 return(0);
1054 return(1);
1055
1056 out:
1057 /*
1058 * header field is out of range
1059 */
1060 paxwarn(1, "Ustar header field is too small for %s", arcn->org_name);
1061 return(1);
1062}
1063
1064/*
1065 * name_split()
1066 * see if the name has to be split for storage in a ustar header. We try
1067 * to fit the entire name in the name field without splitting if we can.
1068 * The split point is always at a /
1069 * Return
1070 * character pointer to split point (always the / that is to be removed
1071 * if the split is not needed, the points is set to the start of the file
1072 * name (it would violate the spec to split there). A NULL is returned if
1073 * the file name is too long
1074 */
1075
1076static char *
1077name_split(char *name, int len)
1078{
1079 char *start;
1080
1081 /*
1082 * check to see if the file name is small enough to fit in the name
1083 * field. if so just return a pointer to the name.
1084 */
1085 if (len <= TNMSZ)
1086 return(name);
1087 if (len > (TPFSZ + TNMSZ + 1))
1088 return(NULL);
1089
1090 /*
1091 * we start looking at the biggest sized piece that fits in the name
1092 * field. We walk forward looking for a slash to split at. The idea is
1093 * to find the biggest piece to fit in the name field (or the smallest
1094 * prefix we can find)
1095 */
1096 start = name + len - TNMSZ - 1;
1097 while ((*start != '\0') && (*start != '/'))
1098 ++start;
1099
1100 /*
1101 * if we hit the end of the string, this name cannot be split, so we
1102 * cannot store this file.
1103 */
1104 if (*start == '\0')
1105 return(NULL);
1106 len = start - name;
1107
1108 /*
1109 * NOTE: /str where the length of str == TNMSZ can not be stored under
1110 * the p1003.1-1990 spec for ustar. We could force a prefix of / and
1111 * the file would then expand on extract to //str. The len == 0 below
1112 * makes this special case follow the spec to the letter.
1113 */
1114 if ((len > TPFSZ) || (len == 0))
1115 return(NULL);
1116
1117 /*
1118 * ok have a split point, return it to the caller
1119 */
1120 return(start);
1121}
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