xref: /freebsd/bin/pax/pax.c (revision a0ee8cc636cd5c2374ec44ca71226564ea0bca95)
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  #if 0
35  #ifndef lint
36  static char const copyright[] =
37  "@(#) Copyright (c) 1992, 1993\n\
38  	The Regents of the University of California.  All rights reserved.\n";
39  #endif /* not lint */
40  
41  #ifndef lint
42  static char sccsid[] = "@(#)pax.c	8.2 (Berkeley) 4/18/94";
43  #endif /* not lint */
44  #endif
45  #include <sys/cdefs.h>
46  __FBSDID("$FreeBSD$");
47  
48  #include <sys/types.h>
49  #include <sys/stat.h>
50  #include <sys/time.h>
51  #include <sys/resource.h>
52  #include <err.h>
53  #include <errno.h>
54  #include <fcntl.h>
55  #include <locale.h>
56  #include <paths.h>
57  #include <signal.h>
58  #include <stdio.h>
59  #include <stdlib.h>
60  #include <string.h>
61  #include "pax.h"
62  #include "extern.h"
63  static int gen_init(void);
64  
65  /*
66   * PAX main routines, general globals and some simple start up routines
67   */
68  
69  /*
70   * Variables that can be accessed by any routine within pax
71   */
72  int	act = DEFOP;		/* read/write/append/copy */
73  FSUB	*frmt = NULL;		/* archive format type */
74  int	cflag;			/* match all EXCEPT pattern/file */
75  int	cwdfd;			/* starting cwd */
76  int	dflag;			/* directory member match only  */
77  int	iflag;			/* interactive file/archive rename */
78  int	kflag;			/* do not overwrite existing files */
79  int	lflag;			/* use hard links when possible */
80  int	nflag;			/* select first archive member match */
81  int	tflag;			/* restore access time after read */
82  int	uflag;			/* ignore older modification time files */
83  int	vflag;			/* produce verbose output */
84  int	Dflag;			/* same as uflag except inode change time */
85  int	Hflag;			/* follow command line symlinks (write only) */
86  int	Lflag;			/* follow symlinks when writing */
87  int	Oflag;			/* limit to single volume */
88  int	Xflag;			/* archive files with same device id only */
89  int	Yflag;			/* same as Dflg except after name mode */
90  int	Zflag;			/* same as uflg except after name mode */
91  int	vfpart;			/* is partial verbose output in progress */
92  int	patime = 1;		/* preserve file access time */
93  int	pmtime = 1;		/* preserve file modification times */
94  int	nodirs;			/* do not create directories as needed */
95  int	pmode;			/* preserve file mode bits */
96  int	pids;			/* preserve file uid/gid */
97  int	rmleadslash = 0;	/* remove leading '/' from pathnames */
98  int	exit_val;		/* exit value */
99  int	docrc;			/* check/create file crc */
100  char	*dirptr;		/* destination dir in a copy */
101  const	char *argv0;		/* root of argv[0] */
102  sigset_t s_mask;		/* signal mask for cleanup critical sect */
103  FILE	*listf;			/* file pointer to print file list to */
104  char	*tempfile;		/* tempfile to use for mkstemp(3) */
105  char	*tempbase;		/* basename of tempfile to use for mkstemp(3) */
106  
107  /*
108   *	PAX - Portable Archive Interchange
109   *
110   * 	A utility to read, write, and write lists of the members of archive
111   *	files and copy directory hierarchies. A variety of archive formats
112   *	are supported (some are described in POSIX 1003.1 10.1):
113   *
114   *		ustar - 10.1.1 extended tar interchange format
115   *		cpio  - 10.1.2 extended cpio interchange format
116   *		tar - old BSD 4.3 tar format
117   *		binary cpio - old cpio with binary header format
118   *		sysVR4 cpio -  with and without CRC
119   *
120   * This version is a superset of IEEE Std 1003.2b-d3
121   *
122   * Summary of Extensions to the IEEE Standard:
123   *
124   * 1	READ ENHANCEMENTS
125   * 1.1	Operations which read archives will continue to operate even when
126   *	processing archives which may be damaged, truncated, or fail to meet
127   *	format specs in several different ways. Damaged sections of archives
128   *	are detected and avoided if possible. Attempts will be made to resync
129   *	archive read operations even with badly damaged media.
130   * 1.2	Blocksize requirements are not strictly enforced on archive read.
131   *	Tapes which have variable sized records can be read without errors.
132   * 1.3	The user can specify via the non-standard option flag -E if error
133   *	resync operation should stop on a media error, try a specified number
134   *	of times to correct, or try to correct forever.
135   * 1.4	Sparse files (lseek holes) stored on the archive (but stored with blocks
136   *	of all zeros will be restored with holes appropriate for the target
137   *	file system
138   * 1.5	The user is notified whenever something is found during archive
139   *	read operations which violates spec (but the read will continue).
140   * 1.6	Multiple archive volumes can be read and may span over different
141   *	archive devices
142   * 1.7	Rigidly restores all file attributes exactly as they are stored on the
143   *	archive.
144   * 1.8	Modification change time ranges can be specified via multiple -T
145   *	options. These allow a user to select files whose modification time
146   *	lies within a specific time range.
147   * 1.9	Files can be selected based on owner (user name or uid) via one or more
148   *	-U options.
149   * 1.10	Files can be selected based on group (group name or gid) via one o
150   *	more -G options.
151   * 1.11	File modification time can be checked against existing file after
152   *	name modification (-Z)
153   *
154   * 2	WRITE ENHANCEMENTS
155   * 2.1	Write operation will stop instead of allowing a user to create a flawed
156   *	flawed archive (due to any problem).
157   * 2.2	Archives written by pax are forced to strictly conform to both the
158   *	archive and pax the specific format specifications.
159   * 2.3	Blocking size and format is rigidly enforced on writes.
160   * 2.4	Formats which may exhibit header overflow problems (they have fields
161   *	too small for large file systems, such as inode number storage), use
162   *	routines designed to repair this problem. These techniques still
163   *	conform to both pax and format specifications, but no longer truncate
164   *	these fields. This removes any restrictions on using these archive
165   *	formats on large file systems.
166   * 2.5	Multiple archive volumes can be written and may span over different
167   *	archive devices
168   * 2.6	A archive volume record limit allows the user to specify the number
169   *	of bytes stored on an archive volume. When reached the user is
170   *	prompted for the next archive volume. This is specified with the
171   *	non-standard -B flag. The limit is rounded up to the next blocksize.
172   * 2.7	All archive padding during write use zero filled sections. This makes
173   *	it much easier to pull data out of flawed archive during read
174   *	operations.
175   * 2.8	Access time reset with the -t applies to all file nodes (including
176   *	directories).
177   * 2.9	Symbolic links can be followed with -L (optional in the spec).
178   * 2.10	Modification or inode change time ranges can be specified via
179   *	multiple -T options. These allow a user to select files whose
180   *	modification or inode change time lies within a specific time range.
181   * 2.11	Files can be selected based on owner (user name or uid) via one or more
182   *	-U options.
183   * 2.12	Files can be selected based on group (group name or gid) via one o
184   *	more -G options.
185   * 2.13	Symlinks which appear on the command line can be followed (without
186   *	following other symlinks; -H flag)
187   *
188   * 3	COPY ENHANCEMENTS
189   * 3.1	Sparse files (lseek holes) can be copied without expanding the holes
190   *	into zero filled blocks. The file copy is created with holes which are
191   *	appropriate for the target file system
192   * 3.2	Access time as well as modification time on copied file trees can be
193   *	preserved with the appropriate -p options.
194   * 3.3	Access time reset with the -t applies to all file nodes (including
195   *	directories).
196   * 3.4	Symbolic links can be followed with -L (optional in the spec).
197   * 3.5	Modification or inode change time ranges can be specified via
198   *	multiple -T options. These allow a user to select files whose
199   *	modification or inode change time lies within a specific time range.
200   * 3.6	Files can be selected based on owner (user name or uid) via one or more
201   *	-U options.
202   * 3.7	Files can be selected based on group (group name or gid) via one o
203   *	more -G options.
204   * 3.8	Symlinks which appear on the command line can be followed (without
205   *	following other symlinks; -H flag)
206   * 3.9  File inode change time can be checked against existing file before
207   *	name modification (-D)
208   * 3.10 File inode change time can be checked against existing file after
209   *	name modification (-Y)
210   * 3.11	File modification time can be checked against existing file after
211   *	name modification (-Z)
212   *
213   * 4	GENERAL ENHANCEMENTS
214   * 4.1	Internal structure is designed to isolate format dependent and
215   *	independent functions. Formats are selected via a format driver table.
216   *	This encourages the addition of new archive formats by only having to
217   *	write those routines which id, read and write the archive header.
218   */
219  
220  /*
221   * main()
222   *	parse options, set up and operate as specified by the user.
223   *	any operational flaw will set exit_val to non-zero
224   * Return: 0 if ok, 1 otherwise
225   */
226  
227  int
228  main(int argc, char *argv[])
229  {
230  	const char *tmpdir;
231  	size_t tdlen;
232  
233  	(void) setlocale(LC_ALL, "");
234  	listf = stderr;
235  	/*
236  	 * Keep a reference to cwd, so we can always come back home.
237  	 */
238  	cwdfd = open(".", O_RDONLY);
239  	if (cwdfd < 0) {
240  		syswarn(0, errno, "Can't open current working directory.");
241  		return(exit_val);
242  	}
243  
244  	/*
245  	 * Where should we put temporary files?
246  	 */
247  	if ((tmpdir = getenv("TMPDIR")) == NULL || *tmpdir == '\0')
248  		tmpdir = _PATH_TMP;
249  	tdlen = strlen(tmpdir);
250  	while(tdlen > 0 && tmpdir[tdlen - 1] == '/')
251  		tdlen--;
252  	tempfile = malloc(tdlen + 1 + sizeof(_TFILE_BASE));
253  	if (tempfile == NULL) {
254  		paxwarn(1, "Cannot allocate memory for temp file name.");
255  		return(exit_val);
256  	}
257  	if (tdlen)
258  		memcpy(tempfile, tmpdir, tdlen);
259  	tempbase = tempfile + tdlen;
260  	*tempbase++ = '/';
261  
262  	/*
263  	 * parse options, determine operational mode, general init
264  	 */
265  	options(argc, argv);
266  	if ((gen_init() < 0) || (tty_init() < 0))
267  		return(exit_val);
268  
269  	/*
270  	 * select a primary operation mode
271  	 */
272  	switch(act) {
273  	case EXTRACT:
274  		extract();
275  		break;
276  	case ARCHIVE:
277  		archive();
278  		break;
279  	case APPND:
280  		if (gzip_program != NULL)
281  			err(1, "can not gzip while appending");
282  		append();
283  		break;
284  	case COPY:
285  		copy();
286  		break;
287  	default:
288  	case LIST:
289  		list();
290  		break;
291  	}
292  	return(exit_val);
293  }
294  
295  /*
296   * sig_cleanup()
297   *	when interrupted we try to do whatever delayed processing we can.
298   *	This is not critical, but we really ought to limit our damage when we
299   *	are aborted by the user.
300   * Return:
301   *	never....
302   */
303  
304  void
305  sig_cleanup(int which_sig)
306  {
307  	/*
308  	 * restore modes and times for any dirs we may have created
309  	 * or any dirs we may have read. Set vflag and vfpart so the user
310  	 * will clearly see the message on a line by itself.
311  	 */
312  	vflag = vfpart = 1;
313  	if (which_sig == SIGXCPU)
314  		paxwarn(0, "Cpu time limit reached, cleaning up.");
315  	else
316  		paxwarn(0, "Signal caught, cleaning up.");
317  
318  	ar_close();
319  	proc_dir();
320  	if (tflag)
321  		atdir_end();
322  	exit(1);
323  }
324  
325  /*
326   * gen_init()
327   *	general setup routines. Not all are required, but they really help
328   *	when dealing with a medium to large sized archives.
329   */
330  
331  static int
332  gen_init(void)
333  {
334  	struct rlimit reslimit;
335  	struct sigaction n_hand;
336  	struct sigaction o_hand;
337  
338  	/*
339  	 * Really needed to handle large archives. We can run out of memory for
340  	 * internal tables really fast when we have a whole lot of files...
341  	 */
342  	if (getrlimit(RLIMIT_DATA , &reslimit) == 0){
343  		reslimit.rlim_cur = reslimit.rlim_max;
344  		(void)setrlimit(RLIMIT_DATA , &reslimit);
345  	}
346  
347  	/*
348  	 * should file size limits be waived? if the os limits us, this is
349  	 * needed if we want to write a large archive
350  	 */
351  	if (getrlimit(RLIMIT_FSIZE , &reslimit) == 0){
352  		reslimit.rlim_cur = reslimit.rlim_max;
353  		(void)setrlimit(RLIMIT_FSIZE , &reslimit);
354  	}
355  
356  	/*
357  	 * increase the size the stack can grow to
358  	 */
359  	if (getrlimit(RLIMIT_STACK , &reslimit) == 0){
360  		reslimit.rlim_cur = reslimit.rlim_max;
361  		(void)setrlimit(RLIMIT_STACK , &reslimit);
362  	}
363  
364  	/*
365  	 * not really needed, but doesn't hurt
366  	 */
367  	if (getrlimit(RLIMIT_RSS , &reslimit) == 0){
368  		reslimit.rlim_cur = reslimit.rlim_max;
369  		(void)setrlimit(RLIMIT_RSS , &reslimit);
370  	}
371  
372  	/*
373  	 * signal handling to reset stored directory times and modes. Since
374  	 * we deal with broken pipes via failed writes we ignore it. We also
375  	 * deal with any file size limit thorough failed writes. Cpu time
376  	 * limits are caught and a cleanup is forced.
377  	 */
378  	if ((sigemptyset(&s_mask) < 0) || (sigaddset(&s_mask, SIGTERM) < 0) ||
379  	    (sigaddset(&s_mask,SIGINT) < 0)||(sigaddset(&s_mask,SIGHUP) < 0) ||
380  	    (sigaddset(&s_mask,SIGPIPE) < 0)||(sigaddset(&s_mask,SIGQUIT)<0) ||
381  	    (sigaddset(&s_mask,SIGXCPU) < 0)||(sigaddset(&s_mask,SIGXFSZ)<0)) {
382  		paxwarn(1, "Unable to set up signal mask");
383  		return(-1);
384  	}
385  	memset(&n_hand, 0, sizeof n_hand);
386  	n_hand.sa_mask = s_mask;
387  	n_hand.sa_flags = 0;
388  	n_hand.sa_handler = sig_cleanup;
389  
390  	if ((sigaction(SIGHUP, &n_hand, &o_hand) < 0) &&
391  	    (o_hand.sa_handler == SIG_IGN) &&
392  	    (sigaction(SIGHUP, &o_hand, &o_hand) < 0))
393  		goto out;
394  
395  	if ((sigaction(SIGTERM, &n_hand, &o_hand) < 0) &&
396  	    (o_hand.sa_handler == SIG_IGN) &&
397  	    (sigaction(SIGTERM, &o_hand, &o_hand) < 0))
398  		goto out;
399  
400  	if ((sigaction(SIGINT, &n_hand, &o_hand) < 0) &&
401  	    (o_hand.sa_handler == SIG_IGN) &&
402  	    (sigaction(SIGINT, &o_hand, &o_hand) < 0))
403  		goto out;
404  
405  	if ((sigaction(SIGQUIT, &n_hand, &o_hand) < 0) &&
406  	    (o_hand.sa_handler == SIG_IGN) &&
407  	    (sigaction(SIGQUIT, &o_hand, &o_hand) < 0))
408  		goto out;
409  
410  	if ((sigaction(SIGXCPU, &n_hand, &o_hand) < 0) &&
411  	    (o_hand.sa_handler == SIG_IGN) &&
412  	    (sigaction(SIGXCPU, &o_hand, &o_hand) < 0))
413  		goto out;
414  
415  	n_hand.sa_handler = SIG_IGN;
416  	if ((sigaction(SIGPIPE, &n_hand, &o_hand) < 0) ||
417  	    (sigaction(SIGXFSZ, &n_hand, &o_hand) < 0))
418  		goto out;
419  	return(0);
420  
421      out:
422  	syswarn(1, errno, "Unable to set up signal handler");
423  	return(-1);
424  }
425