xref: /netbsd-src/bin/pax/pax.c (revision e5548b402ae4c44fb816de42c7bba9581ce23ef5)
1 /*	$NetBSD: pax.c,v 1.37 2005/04/24 01:45:04 christos 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. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #if HAVE_NBTOOL_CONFIG_H
37 #include "nbtool_config.h"
38 #endif
39 
40 #include <sys/cdefs.h>
41 #if !defined(lint)
42 __COPYRIGHT("@(#) Copyright (c) 1992, 1993\n\
43 	The Regents of the University of California.  All rights reserved.\n");
44 #if 0
45 static char sccsid[] = "@(#)pax.c	8.2 (Berkeley) 4/18/94";
46 #else
47 __RCSID("$NetBSD: pax.c,v 1.37 2005/04/24 01:45:04 christos Exp $");
48 #endif
49 #endif /* not lint */
50 
51 #include <sys/types.h>
52 #include <sys/param.h>
53 #include <sys/stat.h>
54 #include <sys/time.h>
55 #include <sys/resource.h>
56 #include <stdio.h>
57 #include <fcntl.h>
58 #include <signal.h>
59 #include <unistd.h>
60 #include <stdlib.h>
61 #include <string.h>
62 #include <errno.h>
63 #include <paths.h>
64 #include "pax.h"
65 #include "extern.h"
66 static int gen_init(void);
67 
68 /*
69  * PAX main routines, general globals and some simple start up routines
70  */
71 
72 /*
73  * Variables that can be accessed by any routine within pax
74  */
75 int	act = ERROR;		/* read/write/append/copy */
76 FSUB	*frmt = NULL;		/* archive format type */
77 int	cflag;			/* match all EXCEPT pattern/file */
78 int	cwdfd = -1;		/* starting cwd */
79 int	dflag;			/* directory member match only  */
80 int	iflag;			/* interactive file/archive rename */
81 int	jflag;			/* pass through bzip2 */
82 int	kflag;			/* do not overwrite existing files */
83 int	lflag;			/* use hard links when possible */
84 int	nflag;			/* select first archive member match */
85 int	tflag;			/* restore access time after read */
86 int	uflag;			/* ignore older modification time files */
87 int	vflag;			/* produce verbose output */
88 int	zflag;			/* use gzip */
89 int	Aflag;			/* honor absolute path */
90 int	Dflag;			/* same as uflag except inode change time */
91 int	Hflag;			/* follow command line symlinks (write only) */
92 int	Lflag;			/* follow symlinks when writing */
93 int	Mflag;			/* treat stdin as an mtree(8) specfile */
94 int	Xflag;			/* archive files with same device id only */
95 int	Yflag;			/* same as Dflg except after name mode */
96 int	Zflag;			/* same as uflg except after name mode */
97 int	vfpart;			/* is partial verbose output in progress */
98 int	patime = 1;		/* preserve file access time */
99 int	pmtime = 1;		/* preserve file modification times */
100 int	nodirs;			/* do not create directories as needed */
101 int	pfflags = 1;		/* preserve file flags */
102 int	pmode;			/* preserve file mode bits */
103 int	pids;			/* preserve file uid/gid */
104 int	rmleadslash = 0;	/* remove leading '/' from pathnames */
105 int	exit_val;		/* exit value */
106 int	docrc;			/* check/create file crc */
107 int	to_stdout;		/* extract to stdout */
108 char	*dirptr;		/* destination dir in a copy */
109 char	*ltmfrmt;		/* -v locale time format (if any) */
110 const char *argv0;		/* root of argv[0] */
111 sigset_t s_mask;		/* signal mask for cleanup critical sect */
112 FILE	*listf;			/* file pointer to print file list to */
113 char	*tempfile;		/* tempfile to use for mkstemp(3) */
114 char	*tempbase;		/* basename of tempfile to use for mkstemp(3) */
115 int	forcelocal;		/* force local operation even if the name
116 				 * contains a :
117 				 */
118 int	secure = 1;		/* don't extract names that contain .. */
119 
120 /*
121  *	PAX - Portable Archive Interchange
122  *
123  *	A utility to read, write, and write lists of the members of archive
124  *	files and copy directory hierarchies. A variety of archive formats
125  *	are supported (some are described in POSIX 1003.1 10.1):
126  *
127  *		ustar - 10.1.1 extended tar interchange format
128  *		cpio  - 10.1.2 extended cpio interchange format
129  *		tar - old BSD 4.3 tar format
130  *		binary cpio - old cpio with binary header format
131  *		sysVR4 cpio -  with and without CRC
132  *
133  * This version is a superset of IEEE Std 1003.2b-d3
134  *
135  * Summary of Extensions to the IEEE Standard:
136  *
137  * 1	READ ENHANCEMENTS
138  * 1.1	Operations which read archives will continue to operate even when
139  *	processing archives which may be damaged, truncated, or fail to meet
140  *	format specs in several different ways. Damaged sections of archives
141  *	are detected and avoided if possible. Attempts will be made to resync
142  *	archive read operations even with badly damaged media.
143  * 1.2	Blocksize requirements are not strictly enforced on archive read.
144  *	Tapes which have variable sized records can be read without errors.
145  * 1.3	The user can specify via the non-standard option flag -E if error
146  *	resync operation should stop on a media error, try a specified number
147  *	of times to correct, or try to correct forever.
148  * 1.4	Sparse files (lseek holes) stored on the archive (but stored with blocks
149  *	of all zeros will be restored with holes appropriate for the target
150  *	filesystem
151  * 1.5	The user is notified whenever something is found during archive
152  *	read operations which violates spec (but the read will continue).
153  * 1.6	Multiple archive volumes can be read and may span over different
154  *	archive devices
155  * 1.7	Rigidly restores all file attributes exactly as they are stored on the
156  *	archive.
157  * 1.8	Modification change time ranges can be specified via multiple -T
158  *	options. These allow a user to select files whose modification time
159  *	lies within a specific time range.
160  * 1.9	Files can be selected based on owner (user name or uid) via one or more
161  *	-U options.
162  * 1.10	Files can be selected based on group (group name or gid) via one o
163  *	more -G options.
164  * 1.11	File modification time can be checked against existing file after
165  *	name modification (-Z)
166  *
167  * 2	WRITE ENHANCEMENTS
168  * 2.1	Write operation will stop instead of allowing a user to create a flawed
169  *	flawed archive (due to any problem).
170  * 2.2	Archives written by pax are forced to strictly conform to both the
171  *	archive and pax the spceific format specifications.
172  * 2.3	Blocking size and format is rigidly enforced on writes.
173  * 2.4	Formats which may exhibit header overflow problems (they have fields
174  *	too small for large file systems, such as inode number storage), use
175  *	routines designed to repair this problem. These techniques still
176  *	conform to both pax and format specifications, but no longer truncate
177  *	these fields. This removes any restrictions on using these archive
178  *	formats on large file systems.
179  * 2.5	Multiple archive volumes can be written and may span over different
180  *	archive devices
181  * 2.6	A archive volume record limit allows the user to specify the number
182  *	of bytes stored on an archive volume. When reached the user is
183  *	prompted for the next archive volume. This is specified with the
184  *	non-standard -B flag. The limit is rounded up to the next blocksize.
185  * 2.7	All archive padding during write use zero filled sections. This makes
186  *	it much easier to pull data out of flawed archive during read
187  *	operations.
188  * 2.8	Access time reset with the -t applies to all file nodes (including
189  *	directories).
190  * 2.9	Symbolic links can be followed with -L (optional in the spec).
191  * 2.10	Modification or inode change time ranges can be specified via
192  *	multiple -T options. These allow a user to select files whose
193  *	modification or inode change time lies within a specific time range.
194  * 2.11	Files can be selected based on owner (user name or uid) via one or more
195  *	-U options.
196  * 2.12	Files can be selected based on group (group name or gid) via one o
197  *	more -G options.
198  * 2.13	Symlinks which appear on the command line can be followed (without
199  *	following other symlinks; -H flag)
200  *
201  * 3	COPY ENHANCEMENTS
202  * 3.1	Sparse files (lseek holes) can be copied without expanding the holes
203  *	into zero filled blocks. The file copy is created with holes which are
204  *	appropriate for the target filesystem
205  * 3.2	Access time as well as modification time on copied file trees can be
206  *	preserved with the appropriate -p options.
207  * 3.3	Access time reset with the -t applies to all file nodes (including
208  *	directories).
209  * 3.4	Symbolic links can be followed with -L (optional in the spec).
210  * 3.5	Modification or inode change time ranges can be specified via
211  *	multiple -T options. These allow a user to select files whose
212  *	modification or inode change time lies within a specific time range.
213  * 3.6	Files can be selected based on owner (user name or uid) via one or more
214  *	-U options.
215  * 3.7	Files can be selected based on group (group name or gid) via one o
216  *	more -G options.
217  * 3.8	Symlinks which appear on the command line can be followed (without
218  *	following other symlinks; -H flag)
219  * 3.9	File inode change time can be checked against existing file before
220  *	name modification (-D)
221  * 3.10	File inode change time can be checked against existing file after
222  *	name modification (-Y)
223  * 3.11	File modification time can be checked against existing file after
224  *	name modification (-Z)
225  *
226  * 4	GENERAL ENHANCEMENTS
227  * 4.1	Internal structure is designed to isolate format dependent and
228  *	independent functions. Formats are selected via a format driver table.
229  *	This encourages the addition of new archive formats by only having to
230  *	write those routines which id, read and write the archive header.
231  */
232 
233 /*
234  * main()
235  *	parse options, set up and operate as specified by the user.
236  *	any operational flaw will set exit_val to non-zero
237  * Return: 0 if ok, 1 otherwise
238  */
239 
240 int
241 main(int argc, char **argv)
242 {
243 	const char *tmpdir;
244 	size_t tdlen;
245 
246 	setprogname(argv[0]);
247 
248 	listf = stderr;
249 
250 	/*
251 	 * parse options, determine operational mode
252 	 */
253 	options(argc, argv);
254 
255 	/*
256 	 * general init
257 	 */
258 	if ((gen_init() < 0) || (tty_init() < 0))
259 		return(exit_val);
260 
261 	/*
262 	 * Keep a reference to cwd, so we can always come back home.
263 	 */
264 	cwdfd = open(".", O_RDONLY);
265 	if (cwdfd < 0) {
266 		syswarn(0, errno, "Can't open current working directory.");
267 		return(exit_val);
268 	}
269 	if (updatepath() == -1)
270 		return(exit_val);
271 
272 	/*
273 	 * Where should we put temporary files?
274 	 */
275 	if ((tmpdir = getenv("TMPDIR")) == NULL || *tmpdir == '\0')
276 		tmpdir = _PATH_TMP;
277 	tdlen = strlen(tmpdir);
278 	while(tdlen > 0 && tmpdir[tdlen - 1] == '/')
279 		tdlen--;
280 	tempfile = malloc(tdlen + 1 + sizeof(_TFILE_BASE));
281 	if (tempfile == NULL) {
282 		tty_warn(1, "Cannot allocate memory for temp file name.");
283 		return(exit_val);
284 	}
285 	if (tdlen)
286 		memcpy(tempfile, tmpdir, tdlen);
287 	tempbase = tempfile + tdlen;
288 	*tempbase++ = '/';
289 
290 	(void)time(&starttime);
291 #ifdef SIGINFO
292 	(void)signal(SIGINFO, ar_summary);
293 #endif
294 	/*
295 	 * select a primary operation mode
296 	 */
297 	switch(act) {
298 	case EXTRACT:
299 		extract();
300 		break;
301 	case ARCHIVE:
302 		archive();
303 		break;
304 	case APPND:
305 		if (gzip_program != NULL)
306 			err(1, "cannot gzip while appending");
307 		append();
308 		/*
309 		 * Check if we tried to append on an empty file and
310 		 * turned into ARCHIVE mode.
311 		 */
312 		if (act == -ARCHIVE) {
313 			act = ARCHIVE;
314 			archive();
315 		}
316 		break;
317 	case COPY:
318 		copy();
319 		break;
320 	default:
321 	case LIST:
322 		list();
323 		break;
324 	}
325 	return(exit_val);
326 }
327 
328 /*
329  * sig_cleanup()
330  *	when interrupted we try to do whatever delayed processing we can.
331  *	This is not critical, but we really ought to limit our damage when we
332  *	are aborted by the user.
333  * Return:
334  *	never....
335  */
336 
337 void
338 sig_cleanup(int which_sig)
339 {
340 	/*
341 	 * restore modes and times for any dirs we may have created
342 	 * or any dirs we may have read. Set vflag and vfpart so the user
343 	 * will clearly see the message on a line by itself.
344 	 */
345 	vflag = vfpart = 1;
346 #ifdef SIGXCPU
347 	if (which_sig == SIGXCPU)
348 		tty_warn(0, "CPU time limit reached, cleaning up.");
349 	else
350 #endif
351 		tty_warn(0, "Signal caught, cleaning up.");
352 
353 	/* delete any open temporary file */
354 	if (xtmp_name)
355 		(void)unlink(xtmp_name);
356 	ar_close();
357 	proc_dir();
358 	if (tflag)
359 		atdir_end();
360 	exit(1);
361 }
362 
363 /*
364  * gen_init()
365  *	general setup routines. Not all are required, but they really help
366  *	when dealing with a medium to large sized archives.
367  */
368 
369 static int
370 gen_init(void)
371 {
372 	struct rlimit reslimit;
373 	struct sigaction n_hand;
374 	struct sigaction o_hand;
375 
376 	/*
377 	 * Really needed to handle large archives. We can run out of memory for
378 	 * internal tables really fast when we have a whole lot of files...
379 	 */
380 	if (getrlimit(RLIMIT_DATA , &reslimit) == 0){
381 		reslimit.rlim_cur = reslimit.rlim_max;
382 		(void)setrlimit(RLIMIT_DATA , &reslimit);
383 	}
384 
385 	/*
386 	 * should file size limits be waived? if the os limits us, this is
387 	 * needed if we want to write a large archive
388 	 */
389 	if (getrlimit(RLIMIT_FSIZE , &reslimit) == 0){
390 		reslimit.rlim_cur = reslimit.rlim_max;
391 		(void)setrlimit(RLIMIT_FSIZE , &reslimit);
392 	}
393 
394 	/*
395 	 * increase the size the stack can grow to
396 	 */
397 	if (getrlimit(RLIMIT_STACK , &reslimit) == 0){
398 		reslimit.rlim_cur = reslimit.rlim_max;
399 		(void)setrlimit(RLIMIT_STACK , &reslimit);
400 	}
401 
402 #ifdef RLIMIT_RSS
403 	/*
404 	 * not really needed, but doesn't hurt
405 	 */
406 	if (getrlimit(RLIMIT_RSS , &reslimit) == 0){
407 		reslimit.rlim_cur = reslimit.rlim_max;
408 		(void)setrlimit(RLIMIT_RSS , &reslimit);
409 	}
410 #endif
411 
412 	/*
413 	 * Handle posix locale
414 	 *
415 	 * set user defines time printing format for -v option
416 	 */
417 	ltmfrmt = getenv("LC_TIME");
418 
419 	/*
420 	 * signal handling to reset stored directory times and modes. Since
421 	 * we deal with broken pipes via failed writes we ignore it. We also
422 	 * deal with any file size limit thorugh failed writes. CPU time
423 	 * limits are caught and a cleanup is forced.
424 	 */
425 	if ((sigemptyset(&s_mask) < 0) || (sigaddset(&s_mask, SIGTERM) < 0) ||
426 	    (sigaddset(&s_mask,SIGINT) < 0)||(sigaddset(&s_mask,SIGHUP) < 0) ||
427 	    (sigaddset(&s_mask,SIGPIPE) < 0)||(sigaddset(&s_mask,SIGQUIT)<0)){
428 		tty_warn(1, "Unable to set up signal mask");
429 		return(-1);
430 	}
431 #ifdef SIGXCPU
432 	if (sigaddset(&s_mask,SIGXCPU) < 0) {
433 		tty_warn(1, "Unable to set up signal mask");
434 		return(-1);
435 	}
436 #endif
437 #ifdef SIGXFSZ
438 	if (sigaddset(&s_mask,SIGXFSZ) < 0) {
439 		tty_warn(1, "Unable to set up signal mask");
440 		return(-1);
441 	}
442 #endif
443 
444 	memset(&n_hand, 0, sizeof n_hand);
445 	n_hand.sa_mask = s_mask;
446 	n_hand.sa_flags = 0;
447 	n_hand.sa_handler = sig_cleanup;
448 
449 	if ((sigaction(SIGHUP, &n_hand, &o_hand) < 0) &&
450 	    (o_hand.sa_handler == SIG_IGN) &&
451 	    (sigaction(SIGHUP, &o_hand, &o_hand) < 0))
452 		goto out;
453 
454 	if ((sigaction(SIGTERM, &n_hand, &o_hand) < 0) &&
455 	    (o_hand.sa_handler == SIG_IGN) &&
456 	    (sigaction(SIGTERM, &o_hand, &o_hand) < 0))
457 		goto out;
458 
459 	if ((sigaction(SIGINT, &n_hand, &o_hand) < 0) &&
460 	    (o_hand.sa_handler == SIG_IGN) &&
461 	    (sigaction(SIGINT, &o_hand, &o_hand) < 0))
462 		goto out;
463 
464 	if ((sigaction(SIGQUIT, &n_hand, &o_hand) < 0) &&
465 	    (o_hand.sa_handler == SIG_IGN) &&
466 	    (sigaction(SIGQUIT, &o_hand, &o_hand) < 0))
467 		goto out;
468 
469 #ifdef SIGXCPU
470 	if ((sigaction(SIGXCPU, &n_hand, &o_hand) < 0) &&
471 	    (o_hand.sa_handler == SIG_IGN) &&
472 	    (sigaction(SIGXCPU, &o_hand, &o_hand) < 0))
473 		goto out;
474 #endif
475 	n_hand.sa_handler = SIG_IGN;
476 	if (sigaction(SIGPIPE, &n_hand, &o_hand) < 0)
477 		goto out;
478 #ifdef SIGXFSZ
479 	if (sigaction(SIGXFSZ, &n_hand, &o_hand) < 0)
480 		goto out;
481 #endif
482 	return(0);
483 
484     out:
485 	syswarn(1, errno, "Unable to set up signal handler");
486 	return(-1);
487 }
488