xref: /netbsd-src/bin/pax/pax.c (revision d710132b4b8ce7f7cccaaf660cb16aa16b4077a0)
1 /*	$NetBSD: pax.c,v 1.27 2003/06/23 13:06:53 grant Exp $	*/
2 
3 /*-
4  * Copyright (c) 1992 Keith Muller.
5  * Copyright (c) 1992, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * This code is derived from software contributed to Berkeley by
9  * Keith Muller of the University of California, San Diego.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. All advertising materials mentioning features or use of this software
20  *    must display the following acknowledgement:
21  *	This product includes software developed by the University of
22  *	California, Berkeley and its contributors.
23  * 4. Neither the name of the University nor the names of its contributors
24  *    may be used to endorse or promote products derived from this software
25  *    without specific prior written permission.
26  *
27  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37  * SUCH DAMAGE.
38  */
39 
40 #include <sys/cdefs.h>
41 #if defined(__COPYRIGHT) && !defined(lint)
42 __COPYRIGHT("@(#) Copyright (c) 1992, 1993\n\
43 	The Regents of the University of California.  All rights reserved.\n");
44 #endif /* not lint */
45 
46 #if defined(__RCSID) && !defined(lint)
47 #if 0
48 static char sccsid[] = "@(#)pax.c	8.2 (Berkeley) 4/18/94";
49 #else
50 __RCSID("$NetBSD: pax.c,v 1.27 2003/06/23 13:06:53 grant Exp $");
51 #endif
52 #endif /* not lint */
53 
54 #include <sys/types.h>
55 #include <sys/param.h>
56 #include <sys/stat.h>
57 #include <sys/time.h>
58 #include <sys/resource.h>
59 #include <stdio.h>
60 #include <fcntl.h>
61 #include <signal.h>
62 #include <unistd.h>
63 #include <stdlib.h>
64 #include <string.h>
65 #include <errno.h>
66 #include <paths.h>
67 #include "pax.h"
68 #include "extern.h"
69 static int gen_init(void);
70 
71 /*
72  * PAX main routines, general globals and some simple start up routines
73  */
74 
75 /*
76  * Variables that can be accessed by any routine within pax
77  */
78 int	act = ERROR;		/* read/write/append/copy */
79 FSUB	*frmt = NULL;		/* archive format type */
80 int	cflag;			/* match all EXCEPT pattern/file */
81 int	cwdfd;			/* starting cwd */
82 int	dflag;			/* directory member match only  */
83 int	iflag;			/* interactive file/archive rename */
84 int	jflag;			/* pass through bzip2 */
85 int	kflag;			/* do not overwrite existing files */
86 int	lflag;			/* use hard links when possible */
87 int	nflag;			/* select first archive member match */
88 int	tflag;			/* restore access time after read */
89 int	uflag;			/* ignore older modification time files */
90 int	vflag;			/* produce verbose output */
91 int	zflag;			/* use gzip */
92 int	Aflag;			/* honor absolute path */
93 int	Dflag;			/* same as uflag except inode change time */
94 int	Hflag;			/* follow command line symlinks (write only) */
95 int	Lflag;			/* follow symlinks when writing */
96 int	Mflag;			/* treat stdin as an mtree(8) specfile */
97 int	Xflag;			/* archive files with same device id only */
98 int	Yflag;			/* same as Dflg except after name mode */
99 int	Zflag;			/* same as uflg except after name mode */
100 int	vfpart;			/* is partial verbose output in progress */
101 int	patime = 1;		/* preserve file access time */
102 int	pmtime = 1;		/* preserve file modification times */
103 int	nodirs;			/* do not create directories as needed */
104 int	pfflags = 1;		/* preserve file flags */
105 int	pmode;			/* preserve file mode bits */
106 int	pids;			/* preserve file uid/gid */
107 int	rmleadslash = 0;	/* remove leading '/' from pathnames */
108 int	exit_val;		/* exit value */
109 int	docrc;			/* check/create file crc */
110 char	*dirptr;		/* destination dir in a copy */
111 char	*ltmfrmt;		/* -v locale time format (if any) */
112 char	*argv0;			/* root of argv[0] */
113 sigset_t s_mask;		/* signal mask for cleanup critical sect */
114 FILE	*listf;			/* file pointer to print file list to */
115 char	*tempfile;		/* tempfile to use for mkstemp(3) */
116 char	*tempbase;		/* basename of tempfile to use for mkstemp(3) */
117 int	forcelocal;		/* force local operation even if the name
118 				 * contains a :
119 				 */
120 int	secure = 1;		/* don't extract names that contain .. */
121 
122 /*
123  *	PAX - Portable Archive Interchange
124  *
125  *	A utility to read, write, and write lists of the members of archive
126  *	files and copy directory hierarchies. A variety of archive formats
127  *	are supported (some are described in POSIX 1003.1 10.1):
128  *
129  *		ustar - 10.1.1 extended tar interchange format
130  *		cpio  - 10.1.2 extended cpio interchange format
131  *		tar - old BSD 4.3 tar format
132  *		binary cpio - old cpio with binary header format
133  *		sysVR4 cpio -  with and without CRC
134  *
135  * This version is a superset of IEEE Std 1003.2b-d3
136  *
137  * Summary of Extensions to the IEEE Standard:
138  *
139  * 1	READ ENHANCEMENTS
140  * 1.1	Operations which read archives will continue to operate even when
141  *	processing archives which may be damaged, truncated, or fail to meet
142  *	format specs in several different ways. Damaged sections of archives
143  *	are detected and avoided if possible. Attempts will be made to resync
144  *	archive read operations even with badly damaged media.
145  * 1.2	Blocksize requirements are not strictly enforced on archive read.
146  *	Tapes which have variable sized records can be read without errors.
147  * 1.3	The user can specify via the non-standard option flag -E if error
148  *	resync operation should stop on a media error, try a specified number
149  *	of times to correct, or try to correct forever.
150  * 1.4	Sparse files (lseek holes) stored on the archive (but stored with blocks
151  *	of all zeros will be restored with holes appropriate for the target
152  *	filesystem
153  * 1.5	The user is notified whenever something is found during archive
154  *	read operations which violates spec (but the read will continue).
155  * 1.6	Multiple archive volumes can be read and may span over different
156  *	archive devices
157  * 1.7	Rigidly restores all file attributes exactly as they are stored on the
158  *	archive.
159  * 1.8	Modification change time ranges can be specified via multiple -T
160  *	options. These allow a user to select files whose modification time
161  *	lies within a specific time range.
162  * 1.9	Files can be selected based on owner (user name or uid) via one or more
163  *	-U options.
164  * 1.10	Files can be selected based on group (group name or gid) via one o
165  *	more -G options.
166  * 1.11	File modification time can be checked against existing file after
167  *	name modification (-Z)
168  *
169  * 2	WRITE ENHANCEMENTS
170  * 2.1	Write operation will stop instead of allowing a user to create a flawed
171  *	flawed archive (due to any problem).
172  * 2.2	Archives written by pax are forced to strictly conform to both the
173  *	archive and pax the spceific format specifications.
174  * 2.3	Blocking size and format is rigidly enforced on writes.
175  * 2.4	Formats which may exhibit header overflow problems (they have fields
176  *	too small for large file systems, such as inode number storage), use
177  *	routines designed to repair this problem. These techniques still
178  *	conform to both pax and format specifications, but no longer truncate
179  *	these fields. This removes any restrictions on using these archive
180  *	formats on large file systems.
181  * 2.5	Multiple archive volumes can be written and may span over different
182  *	archive devices
183  * 2.6	A archive volume record limit allows the user to specify the number
184  *	of bytes stored on an archive volume. When reached the user is
185  *	prompted for the next archive volume. This is specified with the
186  *	non-standard -B flag. The limit is rounded up to the next blocksize.
187  * 2.7	All archive padding during write use zero filled sections. This makes
188  *	it much easier to pull data out of flawed archive during read
189  *	operations.
190  * 2.8	Access time reset with the -t applies to all file nodes (including
191  *	directories).
192  * 2.9	Symbolic links can be followed with -L (optional in the spec).
193  * 2.10	Modification or inode change time ranges can be specified via
194  *	multiple -T options. These allow a user to select files whose
195  *	modification or inode change time lies within a specific time range.
196  * 2.11	Files can be selected based on owner (user name or uid) via one or more
197  *	-U options.
198  * 2.12	Files can be selected based on group (group name or gid) via one o
199  *	more -G options.
200  * 2.13	Symlinks which appear on the command line can be followed (without
201  *	following other symlinks; -H flag)
202  *
203  * 3	COPY ENHANCEMENTS
204  * 3.1	Sparse files (lseek holes) can be copied without expanding the holes
205  *	into zero filled blocks. The file copy is created with holes which are
206  *	appropriate for the target filesystem
207  * 3.2	Access time as well as modification time on copied file trees can be
208  *	preserved with the appropriate -p options.
209  * 3.3	Access time reset with the -t applies to all file nodes (including
210  *	directories).
211  * 3.4	Symbolic links can be followed with -L (optional in the spec).
212  * 3.5	Modification or inode change time ranges can be specified via
213  *	multiple -T options. These allow a user to select files whose
214  *	modification or inode change time lies within a specific time range.
215  * 3.6	Files can be selected based on owner (user name or uid) via one or more
216  *	-U options.
217  * 3.7	Files can be selected based on group (group name or gid) via one o
218  *	more -G options.
219  * 3.8	Symlinks which appear on the command line can be followed (without
220  *	following other symlinks; -H flag)
221  * 3.9	File inode change time can be checked against existing file before
222  *	name modification (-D)
223  * 3.10	File inode change time can be checked against existing file after
224  *	name modification (-Y)
225  * 3.11	File modification time can be checked against existing file after
226  *	name modification (-Z)
227  *
228  * 4	GENERAL ENHANCEMENTS
229  * 4.1	Internal structure is designed to isolate format dependent and
230  *	independent functions. Formats are selected via a format driver table.
231  *	This encourages the addition of new archive formats by only having to
232  *	write those routines which id, read and write the archive header.
233  */
234 
235 /*
236  * main()
237  *	parse options, set up and operate as specified by the user.
238  *	any operational flaw will set exit_val to non-zero
239  * Return: 0 if ok, 1 otherwise
240  */
241 
242 int
243 main(int argc, char **argv)
244 {
245 	char *tmpdir;
246 	size_t tdlen;
247 
248 	setprogname(argv[0]);
249 
250 	listf = stderr;
251 
252 	/*
253 	 * Keep a reference to cwd, so we can always come back home.
254 	 */
255 	cwdfd = open(".", O_RDONLY);
256 	if (cwdfd < 0) {
257 		syswarn(0, errno, "Can't open current working directory.");
258 		return(exit_val);
259 	}
260 
261 	/*
262 	 * Where should we put temporary files?
263 	 */
264 	if ((tmpdir = getenv("TMPDIR")) == NULL || *tmpdir == '\0')
265 		tmpdir = _PATH_TMP;
266 	tdlen = strlen(tmpdir);
267 	while(tdlen > 0 && tmpdir[tdlen - 1] == '/')
268 		tdlen--;
269 	tempfile = malloc(tdlen + 1 + sizeof(_TFILE_BASE));
270 	if (tempfile == NULL) {
271 		tty_warn(1, "Cannot allocate memory for temp file name.");
272 		return(exit_val);
273 	}
274 	if (tdlen)
275 		memcpy(tempfile, tmpdir, tdlen);
276 	tempbase = tempfile + tdlen;
277 	*tempbase++ = '/';
278 
279 	/*
280 	 * parse options, determine operational mode, general init
281 	 */
282 	options(argc, argv);
283 	if ((gen_init() < 0) || (tty_init() < 0))
284 		return(exit_val);
285 
286 	(void)time(&starttime);
287 #ifdef SIGINFO
288 	(void)signal(SIGINFO, ar_summary);
289 #endif
290 	/*
291 	 * select a primary operation mode
292 	 */
293 	switch(act) {
294 	case EXTRACT:
295 		extract();
296 		break;
297 	case ARCHIVE:
298 		archive();
299 		break;
300 	case APPND:
301 		if (gzip_program != NULL)
302 			err(1, "cannot gzip while appending");
303 		append();
304 		/*
305 		 * Check if we tried to append on an empty file and
306 		 * turned into ARCHIVE mode.
307 		 */
308 		if (act == -ARCHIVE) {
309 			act = ARCHIVE;
310 			archive();
311 		}
312 		break;
313 	case COPY:
314 		copy();
315 		break;
316 	default:
317 	case LIST:
318 		list();
319 		break;
320 	}
321 	return(exit_val);
322 }
323 
324 /*
325  * sig_cleanup()
326  *	when interrupted we try to do whatever delayed processing we can.
327  *	This is not critical, but we really ought to limit our damage when we
328  *	are aborted by the user.
329  * Return:
330  *	never....
331  */
332 
333 void
334 sig_cleanup(int which_sig)
335 {
336 	/*
337 	 * restore modes and times for any dirs we may have created
338 	 * or any dirs we may have read. Set vflag and vfpart so the user
339 	 * will clearly see the message on a line by itself.
340 	 */
341 	vflag = vfpart = 1;
342 	if (which_sig == SIGXCPU)
343 		tty_warn(0, "Cpu time limit reached, cleaning up.");
344 	else
345 		tty_warn(0, "Signal caught, cleaning up.");
346 
347 	ar_close();
348 	proc_dir();
349 	if (tflag)
350 		atdir_end();
351 	exit(1);
352 }
353 
354 /*
355  * gen_init()
356  *	general setup routines. Not all are required, but they really help
357  *	when dealing with a medium to large sized archives.
358  */
359 
360 static int
361 gen_init(void)
362 {
363 	struct rlimit reslimit;
364 	struct sigaction n_hand;
365 	struct sigaction o_hand;
366 
367 	/*
368 	 * Really needed to handle large archives. We can run out of memory for
369 	 * internal tables really fast when we have a whole lot of files...
370 	 */
371 	if (getrlimit(RLIMIT_DATA , &reslimit) == 0){
372 		reslimit.rlim_cur = reslimit.rlim_max;
373 		(void)setrlimit(RLIMIT_DATA , &reslimit);
374 	}
375 
376 	/*
377 	 * should file size limits be waived? if the os limits us, this is
378 	 * needed if we want to write a large archive
379 	 */
380 	if (getrlimit(RLIMIT_FSIZE , &reslimit) == 0){
381 		reslimit.rlim_cur = reslimit.rlim_max;
382 		(void)setrlimit(RLIMIT_FSIZE , &reslimit);
383 	}
384 
385 	/*
386 	 * increase the size the stack can grow to
387 	 */
388 	if (getrlimit(RLIMIT_STACK , &reslimit) == 0){
389 		reslimit.rlim_cur = reslimit.rlim_max;
390 		(void)setrlimit(RLIMIT_STACK , &reslimit);
391 	}
392 
393 #ifdef RLIMIT_RSS
394 	/*
395 	 * not really needed, but doesn't hurt
396 	 */
397 	if (getrlimit(RLIMIT_RSS , &reslimit) == 0){
398 		reslimit.rlim_cur = reslimit.rlim_max;
399 		(void)setrlimit(RLIMIT_RSS , &reslimit);
400 	}
401 #endif
402 
403 	/*
404 	 * Handle posix locale
405 	 *
406 	 * set user defines time printing format for -v option
407 	 */
408 	ltmfrmt = getenv("LC_TIME");
409 
410 	/*
411 	 * signal handling to reset stored directory times and modes. Since
412 	 * we deal with broken pipes via failed writes we ignore it. We also
413 	 * deal with any file size limit thorugh failed writes. Cpu time
414 	 * limits are caught and a cleanup is forced.
415 	 */
416 	if ((sigemptyset(&s_mask) < 0) || (sigaddset(&s_mask, SIGTERM) < 0) ||
417 	    (sigaddset(&s_mask,SIGINT) < 0)||(sigaddset(&s_mask,SIGHUP) < 0) ||
418 	    (sigaddset(&s_mask,SIGPIPE) < 0)||(sigaddset(&s_mask,SIGQUIT)<0) ||
419 	    (sigaddset(&s_mask,SIGXCPU) < 0)||(sigaddset(&s_mask,SIGXFSZ)<0)) {
420 		tty_warn(1, "Unable to set up signal mask");
421 		return(-1);
422 	}
423 	memset(&n_hand, 0, sizeof n_hand);
424 	n_hand.sa_mask = s_mask;
425 	n_hand.sa_flags = 0;
426 	n_hand.sa_handler = sig_cleanup;
427 
428 	if ((sigaction(SIGHUP, &n_hand, &o_hand) < 0) &&
429 	    (o_hand.sa_handler == SIG_IGN) &&
430 	    (sigaction(SIGHUP, &o_hand, &o_hand) < 0))
431 		goto out;
432 
433 	if ((sigaction(SIGTERM, &n_hand, &o_hand) < 0) &&
434 	    (o_hand.sa_handler == SIG_IGN) &&
435 	    (sigaction(SIGTERM, &o_hand, &o_hand) < 0))
436 		goto out;
437 
438 	if ((sigaction(SIGINT, &n_hand, &o_hand) < 0) &&
439 	    (o_hand.sa_handler == SIG_IGN) &&
440 	    (sigaction(SIGINT, &o_hand, &o_hand) < 0))
441 		goto out;
442 
443 	if ((sigaction(SIGQUIT, &n_hand, &o_hand) < 0) &&
444 	    (o_hand.sa_handler == SIG_IGN) &&
445 	    (sigaction(SIGQUIT, &o_hand, &o_hand) < 0))
446 		goto out;
447 
448 	if ((sigaction(SIGXCPU, &n_hand, &o_hand) < 0) &&
449 	    (o_hand.sa_handler == SIG_IGN) &&
450 	    (sigaction(SIGXCPU, &o_hand, &o_hand) < 0))
451 		goto out;
452 
453 	n_hand.sa_handler = SIG_IGN;
454 	if ((sigaction(SIGPIPE, &n_hand, &o_hand) < 0) ||
455 	    (sigaction(SIGXFSZ, &n_hand, &o_hand) < 0))
456 		goto out;
457 	return(0);
458 
459     out:
460 	syswarn(1, errno, "Unable to set up signal handler");
461 	return(-1);
462 }
463