1 /* $OpenBSD: pax.c,v 1.38 2014/11/23 05:28:12 guenther Exp $ */ 2 /* $NetBSD: pax.c,v 1.5 1996/03/26 23:54:20 mrg Exp $ */ 3 4 /*- 5 * Copyright (c) 1992 Keith Muller. 6 * Copyright (c) 1992, 1993 7 * The Regents of the University of California. All rights reserved. 8 * 9 * This code is derived from software contributed to Berkeley by 10 * Keith Muller of the University of California, San Diego. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37 #include <sys/types.h> 38 #include <sys/stat.h> 39 #include <sys/time.h> 40 #include <sys/resource.h> 41 #include <signal.h> 42 #include <unistd.h> 43 #include <stdlib.h> 44 #include <string.h> 45 #include <errno.h> 46 #include <err.h> 47 #include <fcntl.h> 48 #include <paths.h> 49 #include <stdio.h> 50 51 #include "pax.h" 52 #include "extern.h" 53 static int gen_init(void); 54 55 /* 56 * PAX main routines, general globals and some simple start up routines 57 */ 58 59 /* 60 * Variables that can be accessed by any routine within pax 61 */ 62 int act = DEFOP; /* read/write/append/copy */ 63 FSUB *frmt = NULL; /* archive format type */ 64 int cflag; /* match all EXCEPT pattern/file */ 65 int cwdfd; /* starting cwd */ 66 int dflag; /* directory member match only */ 67 int iflag; /* interactive file/archive rename */ 68 int kflag; /* do not overwrite existing files */ 69 int lflag; /* use hard links when possible */ 70 int nflag; /* select first archive member match */ 71 int tflag; /* restore access time after read */ 72 int uflag; /* ignore older modification time files */ 73 int vflag; /* produce verbose output */ 74 int Dflag; /* same as uflag except inode change time */ 75 int Hflag; /* follow command line symlinks (write only) */ 76 int Lflag; /* follow symlinks when writing */ 77 int Nflag; /* only use numeric uid and gid */ 78 int Xflag; /* archive files with same device id only */ 79 int Yflag; /* same as Dflag except after name mode */ 80 int Zflag; /* same as uflag except after name mode */ 81 int zeroflag; /* use \0 as pathname terminator */ 82 int vfpart; /* is partial verbose output in progress */ 83 int patime = 1; /* preserve file access time */ 84 int pmtime = 1; /* preserve file modification times */ 85 int nodirs; /* do not create directories as needed */ 86 int pmode; /* preserve file mode bits */ 87 int pids; /* preserve file uid/gid */ 88 int rmleadslash = 0; /* remove leading '/' from pathnames */ 89 int exit_val; /* exit value */ 90 int docrc; /* check/create file crc */ 91 char *dirptr; /* destination dir in a copy */ 92 char *argv0; /* root of argv[0] */ 93 sigset_t s_mask; /* signal mask for cleanup critical sect */ 94 FILE *listf = stderr; /* file pointer to print file list to */ 95 int listfd = STDERR_FILENO; /* fd matching listf, for sighandler output */ 96 char *tempfile; /* tempfile to use for mkstemp(3) */ 97 char *tempbase; /* basename of tempfile to use for mkstemp(3) */ 98 99 /* 100 * PAX - Portable Archive Interchange 101 * 102 * A utility to read, write, and write lists of the members of archive 103 * files and copy directory hierarchies. A variety of archive formats 104 * are supported (some are described in POSIX 1003.1 10.1): 105 * 106 * ustar - 10.1.1 extended tar interchange format 107 * cpio - 10.1.2 extended cpio interchange format 108 * tar - old BSD 4.3 tar format 109 * binary cpio - old cpio with binary header format 110 * sysVR4 cpio - with and without CRC 111 * 112 * This version is a superset of IEEE Std 1003.2b-d3 113 * 114 * Summary of Extensions to the IEEE Standard: 115 * 116 * 1 READ ENHANCEMENTS 117 * 1.1 Operations which read archives will continue to operate even when 118 * processing archives which may be damaged, truncated, or fail to meet 119 * format specs in several different ways. Damaged sections of archives 120 * are detected and avoided if possible. Attempts will be made to resync 121 * archive read operations even with badly damaged media. 122 * 1.2 Blocksize requirements are not strictly enforced on archive read. 123 * Tapes which have variable sized records can be read without errors. 124 * 1.3 The user can specify via the non-standard option flag -E if error 125 * resync operation should stop on a media error, try a specified number 126 * of times to correct, or try to correct forever. 127 * 1.4 Sparse files (lseek holes) stored on the archive (but stored with blocks 128 * of all zeros will be restored with holes appropriate for the target 129 * filesystem 130 * 1.5 The user is notified whenever something is found during archive 131 * read operations which violates spec (but the read will continue). 132 * 1.6 Multiple archive volumes can be read and may span over different 133 * archive devices 134 * 1.7 Rigidly restores all file attributes exactly as they are stored on the 135 * archive. 136 * 1.8 Modification change time ranges can be specified via multiple -T 137 * options. These allow a user to select files whose modification time 138 * lies within a specific time range. 139 * 1.9 Files can be selected based on owner (user name or uid) via one or more 140 * -U options. 141 * 1.10 Files can be selected based on group (group name or gid) via one o 142 * more -G options. 143 * 1.11 File modification time can be checked against existing file after 144 * name modification (-Z) 145 * 146 * 2 WRITE ENHANCEMENTS 147 * 2.1 Write operation will stop instead of allowing a user to create a flawed 148 * flawed archive (due to any problem). 149 * 2.2 Archives written by pax are forced to strictly conform to both the 150 * archive and pax the specific format specifications. 151 * 2.3 Blocking size and format is rigidly enforced on writes. 152 * 2.4 Formats which may exhibit header overflow problems (they have fields 153 * too small for large file systems, such as inode number storage), use 154 * routines designed to repair this problem. These techniques still 155 * conform to both pax and format specifications, but no longer truncate 156 * these fields. This removes any restrictions on using these archive 157 * formats on large file systems. 158 * 2.5 Multiple archive volumes can be written and may span over different 159 * archive devices 160 * 2.6 A archive volume record limit allows the user to specify the number 161 * of bytes stored on an archive volume. When reached the user is 162 * prompted for the next archive volume. This is specified with the 163 * non-standard -B flag. The limit is rounded up to the next blocksize. 164 * 2.7 All archive padding during write use zero filled sections. This makes 165 * it much easier to pull data out of flawed archive during read 166 * operations. 167 * 2.8 Access time reset with the -t applies to all file nodes (including 168 * directories). 169 * 2.9 Symbolic links can be followed with -L (optional in the spec). 170 * 2.10 Modification or inode change time ranges can be specified via 171 * multiple -T options. These allow a user to select files whose 172 * modification or inode change time lies within a specific time range. 173 * 2.11 Files can be selected based on owner (user name or uid) via one or more 174 * -U options. 175 * 2.12 Files can be selected based on group (group name or gid) via one o 176 * more -G options. 177 * 2.13 Symlinks which appear on the command line can be followed (without 178 * following other symlinks; -H flag) 179 * 180 * 3 COPY ENHANCEMENTS 181 * 3.1 Sparse files (lseek holes) can be copied without expanding the holes 182 * into zero filled blocks. The file copy is created with holes which are 183 * appropriate for the target filesystem 184 * 3.2 Access time as well as modification time on copied file trees can be 185 * preserved with the appropriate -p options. 186 * 3.3 Access time reset with the -t applies to all file nodes (including 187 * directories). 188 * 3.4 Symbolic links can be followed with -L (optional in the spec). 189 * 3.5 Modification or inode change time ranges can be specified via 190 * multiple -T options. These allow a user to select files whose 191 * modification or inode change time lies within a specific time range. 192 * 3.6 Files can be selected based on owner (user name or uid) via one or more 193 * -U options. 194 * 3.7 Files can be selected based on group (group name or gid) via one o 195 * more -G options. 196 * 3.8 Symlinks which appear on the command line can be followed (without 197 * following other symlinks; -H flag) 198 * 3.9 File inode change time can be checked against existing file before 199 * name modification (-D) 200 * 3.10 File inode change time can be checked against existing file after 201 * name modification (-Y) 202 * 3.11 File modification time can be checked against existing file after 203 * name modification (-Z) 204 * 205 * 4 GENERAL ENHANCEMENTS 206 * 4.1 Internal structure is designed to isolate format dependent and 207 * independent functions. Formats are selected via a format driver table. 208 * This encourages the addition of new archive formats by only having to 209 * write those routines which id, read and write the archive header. 210 */ 211 212 /* 213 * main() 214 * parse options, set up and operate as specified by the user. 215 * any operational flaw will set exit_val to non-zero 216 * Return: 0 if ok, 1 otherwise 217 */ 218 219 int 220 main(int argc, char **argv) 221 { 222 char *tmpdir; 223 size_t tdlen; 224 225 /* 226 * Keep a reference to cwd, so we can always come back home. 227 */ 228 cwdfd = open(".", O_RDONLY | O_CLOEXEC); 229 if (cwdfd < 0) { 230 syswarn(1, errno, "Can't open current working directory."); 231 return(exit_val); 232 } 233 234 /* 235 * Where should we put temporary files? 236 */ 237 if ((tmpdir = getenv("TMPDIR")) == NULL || *tmpdir == '\0') 238 tmpdir = _PATH_TMP; 239 tdlen = strlen(tmpdir); 240 while (tdlen > 0 && tmpdir[tdlen - 1] == '/') 241 tdlen--; 242 tempfile = malloc(tdlen + 1 + sizeof(_TFILE_BASE)); 243 if (tempfile == NULL) { 244 paxwarn(1, "Cannot allocate memory for temp file name."); 245 return(exit_val); 246 } 247 if (tdlen) 248 memcpy(tempfile, tmpdir, tdlen); 249 tempbase = tempfile + tdlen; 250 *tempbase++ = '/'; 251 252 /* 253 * parse options, determine operational mode, general init 254 */ 255 options(argc, argv); 256 if ((gen_init() < 0) || (tty_init() < 0)) 257 return(exit_val); 258 259 /* 260 * select a primary operation mode 261 */ 262 switch (act) { 263 case EXTRACT: 264 extract(); 265 break; 266 case ARCHIVE: 267 archive(); 268 break; 269 case APPND: 270 if (gzip_program != NULL) 271 errx(1, "can not gzip while appending"); 272 append(); 273 break; 274 case COPY: 275 copy(); 276 break; 277 default: 278 case LIST: 279 list(); 280 break; 281 } 282 return(exit_val); 283 } 284 285 /* 286 * sig_cleanup() 287 * when interrupted we try to do whatever delayed processing we can. 288 * This is not critical, but we really ought to limit our damage when we 289 * are aborted by the user. 290 * Return: 291 * never.... 292 */ 293 294 void 295 sig_cleanup(int which_sig) 296 { 297 char errbuf[80]; 298 299 /* 300 * restore modes and times for any dirs we may have created 301 * or any dirs we may have read. 302 */ 303 304 /* paxwarn() uses stdio; fake it as well as we can */ 305 if (which_sig == SIGXCPU) 306 strlcpy(errbuf, "\nCPU time limit reached, cleaning up.\n", 307 sizeof errbuf); 308 else 309 strlcpy(errbuf, "\nSignal caught, cleaning up.\n", 310 sizeof errbuf); 311 (void) write(STDERR_FILENO, errbuf, strlen(errbuf)); 312 313 ar_close(1); 314 proc_dir(1); 315 if (tflag) 316 atdir_end(); 317 _exit(1); 318 } 319 320 /* 321 * setup_sig() 322 * set a signal to be caught, but only if it isn't being ignored already 323 */ 324 325 static int 326 setup_sig(int sig, const struct sigaction *n_hand) 327 { 328 struct sigaction o_hand; 329 330 if (sigaction(sig, NULL, &o_hand) < 0) 331 return (-1); 332 333 if (o_hand.sa_handler == SIG_IGN) 334 return (0); 335 336 return (sigaction(sig, n_hand, NULL)); 337 } 338 339 /* 340 * gen_init() 341 * general setup routines. Not all are required, but they really help 342 * when dealing with a medium to large sized archives. 343 */ 344 345 static int 346 gen_init(void) 347 { 348 struct rlimit reslimit; 349 struct sigaction n_hand; 350 351 /* 352 * Really needed to handle large archives. We can run out of memory for 353 * internal tables really fast when we have a whole lot of files... 354 */ 355 if (getrlimit(RLIMIT_DATA , &reslimit) == 0){ 356 reslimit.rlim_cur = reslimit.rlim_max; 357 (void)setrlimit(RLIMIT_DATA , &reslimit); 358 } 359 360 /* 361 * should file size limits be waived? if the os limits us, this is 362 * needed if we want to write a large archive 363 */ 364 if (getrlimit(RLIMIT_FSIZE , &reslimit) == 0){ 365 reslimit.rlim_cur = reslimit.rlim_max; 366 (void)setrlimit(RLIMIT_FSIZE , &reslimit); 367 } 368 369 /* 370 * increase the size the stack can grow to 371 */ 372 if (getrlimit(RLIMIT_STACK , &reslimit) == 0){ 373 reslimit.rlim_cur = reslimit.rlim_max; 374 (void)setrlimit(RLIMIT_STACK , &reslimit); 375 } 376 377 /* 378 * not really needed, but doesn't hurt 379 */ 380 if (getrlimit(RLIMIT_RSS , &reslimit) == 0){ 381 reslimit.rlim_cur = reslimit.rlim_max; 382 (void)setrlimit(RLIMIT_RSS , &reslimit); 383 } 384 385 /* 386 * signal handling to reset stored directory times and modes. Since 387 * we deal with broken pipes via failed writes we ignore it. We also 388 * deal with any file size limit through failed writes. Cpu time 389 * limits are caught and a cleanup is forced. 390 */ 391 if ((sigemptyset(&s_mask) < 0) || (sigaddset(&s_mask, SIGTERM) < 0) || 392 (sigaddset(&s_mask,SIGINT) < 0)||(sigaddset(&s_mask,SIGHUP) < 0) || 393 (sigaddset(&s_mask,SIGPIPE) < 0)||(sigaddset(&s_mask,SIGQUIT)<0) || 394 (sigaddset(&s_mask,SIGXCPU) < 0)||(sigaddset(&s_mask,SIGXFSZ)<0)) { 395 paxwarn(1, "Unable to set up signal mask"); 396 return(-1); 397 } 398 399 /* snag the fd to be used from the signal handler */ 400 listfd = fileno(listf); 401 402 memset(&n_hand, 0, sizeof n_hand); 403 n_hand.sa_mask = s_mask; 404 n_hand.sa_flags = 0; 405 n_hand.sa_handler = sig_cleanup; 406 407 if (setup_sig(SIGHUP, &n_hand) || 408 setup_sig(SIGTERM, &n_hand) || 409 setup_sig(SIGINT, &n_hand) || 410 setup_sig(SIGQUIT, &n_hand) || 411 setup_sig(SIGXCPU, &n_hand)) 412 goto out; 413 414 n_hand.sa_handler = SIG_IGN; 415 if ((sigaction(SIGPIPE, &n_hand, NULL) < 0) || 416 (sigaction(SIGXFSZ, &n_hand, NULL) < 0)) 417 goto out; 418 return(0); 419 420 out: 421 syswarn(1, errno, "Unable to set up signal handler"); 422 return(-1); 423 } 424