xref: /freebsd/bin/pax/pax.c (revision c678bc4f13a340ad88debe321afd0097db2590cb)
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  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *	This product includes software developed by the University of
20  *	California, Berkeley and its contributors.
21  * 4. Neither the name of the University nor the names of its contributors
22  *    may be used to endorse or promote products derived from this software
23  *    without specific prior written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35  * SUCH DAMAGE.
36  */
37 
38 #ifndef lint
39 static char const copyright[] =
40 "@(#) Copyright (c) 1992, 1993\n\
41 	The Regents of the University of California.  All rights reserved.\n";
42 #endif /* not lint */
43 
44 #ifndef lint
45 #if 0
46 static char sccsid[] = "@(#)pax.c	8.2 (Berkeley) 4/18/94";
47 #endif
48 static const char rcsid[] =
49   "$FreeBSD$";
50 #endif /* not lint */
51 
52 #include <sys/types.h>
53 #include <sys/stat.h>
54 #include <sys/time.h>
55 #include <sys/resource.h>
56 #include <err.h>
57 #include <errno.h>
58 #include <fcntl.h>
59 #include <locale.h>
60 #include <paths.h>
61 #include <signal.h>
62 #include <stdio.h>
63 #include <stdlib.h>
64 #include <unistd.h>
65 #include "pax.h"
66 #include "extern.h"
67 static int gen_init __P((void));
68 
69 /*
70  * PAX main routines, general globals and some simple start up routines
71  */
72 
73 /*
74  * Variables that can be accessed by any routine within pax
75  */
76 int	act = DEFOP;		/* read/write/append/copy */
77 FSUB	*frmt = NULL;		/* archive format type */
78 int	cflag;			/* match all EXCEPT pattern/file */
79 int	cwdfd;			/* starting cwd */
80 int	dflag;			/* directory member match only  */
81 int	iflag;			/* interactive file/archive rename */
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	Dflag;			/* same as uflag except inode change time */
89 int	Hflag;			/* follow command line symlinks (write only) */
90 int	Lflag;			/* follow symlinks when writing */
91 int	Xflag;			/* archive files with same device id only */
92 int	Yflag;			/* same as Dflg except after name mode */
93 int	Zflag;			/* same as uflg except after name mode */
94 int	vfpart;			/* is partial verbose output in progress */
95 int	patime = 1;		/* preserve file access time */
96 int	pmtime = 1;		/* preserve file modification times */
97 int	nodirs;			/* do not create directories as needed */
98 int	pmode;			/* preserve file mode bits */
99 int	pids;			/* preserve file uid/gid */
100 int	rmleadslash = 0;	/* remove leading '/' from pathnames */
101 int	exit_val;		/* exit value */
102 int	docrc;			/* check/create file crc */
103 char	*dirptr;		/* destination dir in a copy */
104 char	*argv0;			/* root of argv[0] */
105 sigset_t s_mask;		/* signal mask for cleanup critical sect */
106 FILE	*listf = stderr;	/* file pointer to print file list to */
107 char	*tempfile;		/* tempfile to use for mkstemp(3) */
108 char	*tempbase;		/* basename of tempfile to use for mkstemp(3) */
109 
110 /*
111  *	PAX - Portable Archive Interchange
112  *
113  * 	A utility to read, write, and write lists of the members of archive
114  *	files and copy directory hierarchies. A variety of archive formats
115  *	are supported (some are described in POSIX 1003.1 10.1):
116  *
117  *		ustar - 10.1.1 extended tar interchange format
118  *		cpio  - 10.1.2 extended cpio interchange format
119  *		tar - old BSD 4.3 tar format
120  *		binary cpio - old cpio with binary header format
121  *		sysVR4 cpio -  with and without CRC
122  *
123  * This version is a superset of IEEE Std 1003.2b-d3
124  *
125  * Summary of Extensions to the IEEE Standard:
126  *
127  * 1	READ ENHANCEMENTS
128  * 1.1	Operations which read archives will continue to operate even when
129  *	processing archives which may be damaged, truncated, or fail to meet
130  *	format specs in several different ways. Damaged sections of archives
131  *	are detected and avoided if possible. Attempts will be made to resync
132  *	archive read operations even with badly damaged media.
133  * 1.2	Blocksize requirements are not strictly enforced on archive read.
134  *	Tapes which have variable sized records can be read without errors.
135  * 1.3	The user can specify via the non-standard option flag -E if error
136  *	resync operation should stop on a media error, try a specified number
137  *	of times to correct, or try to correct forever.
138  * 1.4	Sparse files (lseek holes) stored on the archive (but stored with blocks
139  *	of all zeros will be restored with holes appropriate for the target
140  *	filesystem
141  * 1.5	The user is notified whenever something is found during archive
142  *	read operations which violates spec (but the read will continue).
143  * 1.6	Multiple archive volumes can be read and may span over different
144  *	archive devices
145  * 1.7	Rigidly restores all file attributes exactly as they are stored on the
146  *	archive.
147  * 1.8	Modification change time ranges can be specified via multiple -T
148  *	options. These allow a user to select files whose modification time
149  *	lies within a specific time range.
150  * 1.9	Files can be selected based on owner (user name or uid) via one or more
151  *	-U options.
152  * 1.10	Files can be selected based on group (group name or gid) via one o
153  *	more -G options.
154  * 1.11	File modification time can be checked against existing file after
155  *	name modification (-Z)
156  *
157  * 2	WRITE ENHANCEMENTS
158  * 2.1	Write operation will stop instead of allowing a user to create a flawed
159  *	flawed archive (due to any problem).
160  * 2.2	Archives written by pax are forced to strictly conform to both the
161  *	archive and pax the specific format specifications.
162  * 2.3	Blocking size and format is rigidly enforced on writes.
163  * 2.4	Formats which may exhibit header overflow problems (they have fields
164  *	too small for large file systems, such as inode number storage), use
165  *	routines designed to repair this problem. These techniques still
166  *	conform to both pax and format specifications, but no longer truncate
167  *	these fields. This removes any restrictions on using these archive
168  *	formats on large file systems.
169  * 2.5	Multiple archive volumes can be written and may span over different
170  *	archive devices
171  * 2.6	A archive volume record limit allows the user to specify the number
172  *	of bytes stored on an archive volume. When reached the user is
173  *	prompted for the next archive volume. This is specified with the
174  *	non-standard -B flag. The limit is rounded up to the next blocksize.
175  * 2.7	All archive padding during write use zero filled sections. This makes
176  *	it much easier to pull data out of flawed archive during read
177  *	operations.
178  * 2.8	Access time reset with the -t applies to all file nodes (including
179  *	directories).
180  * 2.9	Symbolic links can be followed with -L (optional in the spec).
181  * 2.10	Modification or inode change time ranges can be specified via
182  *	multiple -T options. These allow a user to select files whose
183  *	modification or inode change time lies within a specific time range.
184  * 2.11	Files can be selected based on owner (user name or uid) via one or more
185  *	-U options.
186  * 2.12	Files can be selected based on group (group name or gid) via one o
187  *	more -G options.
188  * 2.13	Symlinks which appear on the command line can be followed (without
189  *	following other symlinks; -H flag)
190  *
191  * 3	COPY ENHANCEMENTS
192  * 3.1	Sparse files (lseek holes) can be copied without expanding the holes
193  *	into zero filled blocks. The file copy is created with holes which are
194  *	appropriate for the target filesystem
195  * 3.2	Access time as well as modification time on copied file trees can be
196  *	preserved with the appropriate -p options.
197  * 3.3	Access time reset with the -t applies to all file nodes (including
198  *	directories).
199  * 3.4	Symbolic links can be followed with -L (optional in the spec).
200  * 3.5	Modification or inode change time ranges can be specified via
201  *	multiple -T options. These allow a user to select files whose
202  *	modification or inode change time lies within a specific time range.
203  * 3.6	Files can be selected based on owner (user name or uid) via one or more
204  *	-U options.
205  * 3.7	Files can be selected based on group (group name or gid) via one o
206  *	more -G options.
207  * 3.8	Symlinks which appear on the command line can be followed (without
208  *	following other symlinks; -H flag)
209  * 3.9  File inode change time can be checked against existing file before
210  *	name modification (-D)
211  * 3.10 File inode change time can be checked against existing file after
212  *	name modification (-Y)
213  * 3.11	File modification time can be checked against existing file after
214  *	name modification (-Z)
215  *
216  * 4	GENERAL ENHANCEMENTS
217  * 4.1	Internal structure is designed to isolate format dependent and
218  *	independent functions. Formats are selected via a format driver table.
219  *	This encourages the addition of new archive formats by only having to
220  *	write those routines which id, read and write the archive header.
221  */
222 
223 /*
224  * main()
225  *	parse options, set up and operate as specified by the user.
226  *	any operational flaw will set exit_val to non-zero
227  * Return: 0 if ok, 1 otherwise
228  */
229 
230 #ifdef __STDC__
231 int
232 main(int argc, char **argv)
233 #else
234 int
235 main(argc, argv)
236 	int argc;
237 	char **argv;
238 #endif
239 {
240 	char *tmpdir;
241 	size_t tdlen;
242 
243 	(void) setlocale(LC_ALL, "");
244 	/*
245 	 * Keep a reference to cwd, so we can always come back home.
246 	 */
247 	cwdfd = open(".", O_RDONLY);
248 	if (cwdfd < 0) {
249 		syswarn(0, errno, "Can't open current working directory.");
250 		return(exit_val);
251 	}
252 
253 	/*
254 	 * Where should we put temporary files?
255 	 */
256 	if ((tmpdir = getenv("TMPDIR")) == NULL || *tmpdir == '\0')
257 		tmpdir = _PATH_TMP;
258 	tdlen = strlen(tmpdir);
259 	while(tdlen > 0 && tmpdir[tdlen - 1] == '/')
260 		tdlen--;
261 	tempfile = malloc(tdlen + 1 + sizeof(_TFILE_BASE));
262 	if (tempfile == NULL) {
263 		paxwarn(1, "Cannot allocate memory for temp file name.");
264 		return(exit_val);
265 	}
266 	if (tdlen)
267 		memcpy(tempfile, tmpdir, tdlen);
268 	tempbase = tempfile + tdlen;
269 	*tempbase++ = '/';
270 
271 	/*
272 	 * parse options, determine operational mode, general init
273 	 */
274 	options(argc, argv);
275 	if ((gen_init() < 0) || (tty_init() < 0))
276 		return(exit_val);
277 
278 	/*
279 	 * select a primary operation mode
280 	 */
281 	switch(act) {
282 	case EXTRACT:
283 		extract();
284 		break;
285 	case ARCHIVE:
286 		archive();
287 		break;
288 	case APPND:
289 		if (gzip_program != NULL)
290 			err(1, "can not gzip while appending");
291 		append();
292 		break;
293 	case COPY:
294 		copy();
295 		break;
296 	default:
297 	case LIST:
298 		list();
299 		break;
300 	}
301 	return(exit_val);
302 }
303 
304 /*
305  * sig_cleanup()
306  *	when interrupted we try to do whatever delayed processing we can.
307  *	This is not critical, but we really ought to limit our damage when we
308  *	are aborted by the user.
309  * Return:
310  *	never....
311  */
312 
313 #ifdef __STDC__
314 void
315 sig_cleanup(int which_sig)
316 #else
317 void
318 sig_cleanup(which_sig)
319 	int which_sig;
320 #endif
321 {
322 	/*
323 	 * restore modes and times for any dirs we may have created
324 	 * or any dirs we may have read. Set vflag and vfpart so the user
325 	 * will clearly see the message on a line by itself.
326 	 */
327 	vflag = vfpart = 1;
328 	if (which_sig == SIGXCPU)
329 		paxwarn(0, "Cpu time limit reached, cleaning up.");
330 	else
331 		paxwarn(0, "Signal caught, cleaning up.");
332 
333 	ar_close();
334 	proc_dir();
335 	if (tflag)
336 		atdir_end();
337 	exit(1);
338 }
339 
340 /*
341  * gen_init()
342  *	general setup routines. Not all are required, but they really help
343  *	when dealing with a medium to large sized archives.
344  */
345 
346 #ifdef __STDC__
347 static int
348 gen_init(void)
349 #else
350 static int
351 gen_init()
352 #endif
353 {
354 	struct rlimit reslimit;
355 	struct sigaction n_hand;
356 	struct sigaction o_hand;
357 
358 	/*
359 	 * Really needed to handle large archives. We can run out of memory for
360 	 * internal tables really fast when we have a whole lot of files...
361 	 */
362 	if (getrlimit(RLIMIT_DATA , &reslimit) == 0){
363 		reslimit.rlim_cur = reslimit.rlim_max;
364 		(void)setrlimit(RLIMIT_DATA , &reslimit);
365 	}
366 
367 	/*
368 	 * should file size limits be waived? if the os limits us, this is
369 	 * needed if we want to write a large archive
370 	 */
371 	if (getrlimit(RLIMIT_FSIZE , &reslimit) == 0){
372 		reslimit.rlim_cur = reslimit.rlim_max;
373 		(void)setrlimit(RLIMIT_FSIZE , &reslimit);
374 	}
375 
376 	/*
377 	 * increase the size the stack can grow to
378 	 */
379 	if (getrlimit(RLIMIT_STACK , &reslimit) == 0){
380 		reslimit.rlim_cur = reslimit.rlim_max;
381 		(void)setrlimit(RLIMIT_STACK , &reslimit);
382 	}
383 
384 	/*
385 	 * not really needed, but doesn't hurt
386 	 */
387 	if (getrlimit(RLIMIT_RSS , &reslimit) == 0){
388 		reslimit.rlim_cur = reslimit.rlim_max;
389 		(void)setrlimit(RLIMIT_RSS , &reslimit);
390 	}
391 
392 	/*
393 	 * signal handling to reset stored directory times and modes. Since
394 	 * we deal with broken pipes via failed writes we ignore it. We also
395 	 * deal with any file size limit thorugh failed writes. Cpu time
396 	 * limits are caught and a cleanup is forced.
397 	 */
398 	if ((sigemptyset(&s_mask) < 0) || (sigaddset(&s_mask, SIGTERM) < 0) ||
399 	    (sigaddset(&s_mask,SIGINT) < 0)||(sigaddset(&s_mask,SIGHUP) < 0) ||
400 	    (sigaddset(&s_mask,SIGPIPE) < 0)||(sigaddset(&s_mask,SIGQUIT)<0) ||
401 	    (sigaddset(&s_mask,SIGXCPU) < 0)||(sigaddset(&s_mask,SIGXFSZ)<0)) {
402 		paxwarn(1, "Unable to set up signal mask");
403 		return(-1);
404 	}
405 	memset(&n_hand, 0, sizeof n_hand);
406 	n_hand.sa_mask = s_mask;
407 	n_hand.sa_flags = 0;
408 	n_hand.sa_handler = sig_cleanup;
409 
410 	if ((sigaction(SIGHUP, &n_hand, &o_hand) < 0) &&
411 	    (o_hand.sa_handler == SIG_IGN) &&
412 	    (sigaction(SIGHUP, &o_hand, &o_hand) < 0))
413 		goto out;
414 
415 	if ((sigaction(SIGTERM, &n_hand, &o_hand) < 0) &&
416 	    (o_hand.sa_handler == SIG_IGN) &&
417 	    (sigaction(SIGTERM, &o_hand, &o_hand) < 0))
418 		goto out;
419 
420 	if ((sigaction(SIGINT, &n_hand, &o_hand) < 0) &&
421 	    (o_hand.sa_handler == SIG_IGN) &&
422 	    (sigaction(SIGINT, &o_hand, &o_hand) < 0))
423 		goto out;
424 
425 	if ((sigaction(SIGQUIT, &n_hand, &o_hand) < 0) &&
426 	    (o_hand.sa_handler == SIG_IGN) &&
427 	    (sigaction(SIGQUIT, &o_hand, &o_hand) < 0))
428 		goto out;
429 
430 	if ((sigaction(SIGXCPU, &n_hand, &o_hand) < 0) &&
431 	    (o_hand.sa_handler == SIG_IGN) &&
432 	    (sigaction(SIGXCPU, &o_hand, &o_hand) < 0))
433 		goto out;
434 
435 	n_hand.sa_handler = SIG_IGN;
436 	if ((sigaction(SIGPIPE, &n_hand, &o_hand) < 0) ||
437 	    (sigaction(SIGXFSZ, &n_hand, &o_hand) < 0))
438 		goto out;
439 	return(0);
440 
441     out:
442 	syswarn(1, errno, "Unable to set up signal handler");
443 	return(-1);
444 }
445