xref: /freebsd/sbin/restore/tape.c (revision 2546665afcaf0d53dc2c7058fee96354b3680f5a)
1 /*
2  * Copyright (c) 1983, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  * (c) UNIX System Laboratories, Inc.
5  * All or some portions of this file are derived from material licensed
6  * to the University of California by American Telephone and Telegraph
7  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
8  * the permission of UNIX System Laboratories, Inc.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 4. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 #ifndef lint
36 #if 0
37 static char sccsid[] = "@(#)tape.c	8.9 (Berkeley) 5/1/95";
38 #endif
39 static const char rcsid[] =
40   "$FreeBSD$";
41 #endif /* not lint */
42 
43 #include <sys/param.h>
44 #include <sys/file.h>
45 #include <sys/mtio.h>
46 #include <sys/stat.h>
47 #include <sys/time.h>
48 
49 #include <ufs/ufs/dinode.h>
50 #include <protocols/dumprestore.h>
51 
52 #include <errno.h>
53 #include <limits.h>
54 #include <paths.h>
55 #include <setjmp.h>
56 #include <stdio.h>
57 #include <stdlib.h>
58 #include <string.h>
59 #include <time.h>
60 #include <timeconv.h>
61 #include <unistd.h>
62 
63 #include "restore.h"
64 #include "extern.h"
65 
66 static long	fssize = MAXBSIZE;
67 static int	mt = -1;
68 static int	pipein = 0;
69 static int	pipecmdin = 0;
70 static FILE	*popenfp = NULL;
71 static char	*magtape;
72 static int	blkcnt;
73 static int	numtrec;
74 static char	*tapebuf;
75 static union	u_spcl endoftapemark;
76 static long	blksread;		/* blocks read since last header */
77 static int64_t	tapeaddr = 0;		/* current TP_BSIZE tape record */
78 static long	tapesread;
79 static jmp_buf	restart;
80 static int	gettingfile = 0;	/* restart has a valid frame */
81 static char	*host = NULL;
82 static int	readmapflag;
83 
84 static int	ofile;
85 static char	*map;
86 static char	lnkbuf[MAXPATHLEN + 1];
87 static int	pathlen;
88 
89 int		Bcvt;		/* Swap Bytes */
90 
91 #define	FLUSHTAPEBUF()	blkcnt = ntrec + 1
92 
93 static void	 accthdr(struct s_spcl *);
94 static int	 checksum(int *);
95 static void	 findinode(struct s_spcl *);
96 static void	 findtapeblksize(void);
97 static int	 gethead(struct s_spcl *);
98 static void	 readtape(char *);
99 static void	 setdumpnum(void);
100 static u_long	 swabl(u_long);
101 static u_char	*swablong(u_char *, int);
102 static u_char	*swabshort(u_char *, int);
103 static void	 terminateinput(void);
104 static void	 xtrfile(char *, long);
105 static void	 xtrlnkfile(char *, long);
106 static void	 xtrlnkskip(char *, long);
107 static void	 xtrmap(char *, long);
108 static void	 xtrmapskip(char *, long);
109 static void	 xtrskip(char *, long);
110 
111 /*
112  * Set up an input source
113  */
114 void
115 setinput(char *source, int ispipecommand)
116 {
117 	FLUSHTAPEBUF();
118 	if (bflag)
119 		newtapebuf(ntrec);
120 	else
121 		newtapebuf(NTREC > HIGHDENSITYTREC ? NTREC : HIGHDENSITYTREC);
122 	terminal = stdin;
123 
124 	if (ispipecommand)
125 		pipecmdin++;
126 	else
127 #ifdef RRESTORE
128 	if (strchr(source, ':')) {
129 		host = source;
130 		source = strchr(host, ':');
131 		*source++ = '\0';
132 		if (rmthost(host) == 0)
133 			done(1);
134 	} else
135 #endif
136 	if (strcmp(source, "-") == 0) {
137 		/*
138 		 * Since input is coming from a pipe we must establish
139 		 * our own connection to the terminal.
140 		 */
141 		terminal = fopen(_PATH_TTY, "r");
142 		if (terminal == NULL) {
143 			(void)fprintf(stderr, "cannot open %s: %s\n",
144 			    _PATH_TTY, strerror(errno));
145 			terminal = fopen(_PATH_DEVNULL, "r");
146 			if (terminal == NULL) {
147 				(void)fprintf(stderr, "cannot open %s: %s\n",
148 				    _PATH_DEVNULL, strerror(errno));
149 				done(1);
150 			}
151 		}
152 		pipein++;
153 	}
154 	setuid(getuid());	/* no longer need or want root privileges */
155 	magtape = strdup(source);
156 	if (magtape == NULL) {
157 		fprintf(stderr, "Cannot allocate space for magtape buffer\n");
158 		done(1);
159 	}
160 }
161 
162 void
163 newtapebuf(long size)
164 {
165 	static int tapebufsize = -1;
166 
167 	ntrec = size;
168 	if (size <= tapebufsize)
169 		return;
170 	if (tapebuf != NULL)
171 		free(tapebuf);
172 	tapebuf = malloc(size * TP_BSIZE);
173 	if (tapebuf == NULL) {
174 		fprintf(stderr, "Cannot allocate space for tape buffer\n");
175 		done(1);
176 	}
177 	tapebufsize = size;
178 }
179 
180 /*
181  * Verify that the tape drive can be accessed and
182  * that it actually is a dump tape.
183  */
184 void
185 setup(void)
186 {
187 	int i, j, *ip;
188 	struct stat stbuf;
189 
190 	vprintf(stdout, "Verify tape and initialize maps\n");
191 	if (pipecmdin) {
192 		if (setenv("RESTORE_VOLUME", "1", 1) == -1) {
193 			fprintf(stderr, "Cannot set $RESTORE_VOLUME: %s\n",
194 			    strerror(errno));
195 			done(1);
196 		}
197 		popenfp = popen(magtape, "r");
198 		mt = popenfp ? fileno(popenfp) : -1;
199 	} else
200 #ifdef RRESTORE
201 	if (host)
202 		mt = rmtopen(magtape, 0);
203 	else
204 #endif
205 	if (pipein)
206 		mt = 0;
207 	else
208 		mt = open(magtape, O_RDONLY, 0);
209 	if (mt < 0) {
210 		fprintf(stderr, "%s: %s\n", magtape, strerror(errno));
211 		done(1);
212 	}
213 	volno = 1;
214 	setdumpnum();
215 	FLUSHTAPEBUF();
216 	if (!pipein && !bflag)
217 		findtapeblksize();
218 	if (gethead(&spcl) == FAIL) {
219 		fprintf(stderr, "Tape is not a dump tape\n");
220 		done(1);
221 	}
222 	if (pipein) {
223 		endoftapemark.s_spcl.c_magic = FS_UFS2_MAGIC;
224 		endoftapemark.s_spcl.c_type = TS_END;
225 		ip = (int *)&endoftapemark;
226 		j = sizeof(union u_spcl) / sizeof(int);
227 		i = 0;
228 		do
229 			i += *ip++;
230 		while (--j);
231 		endoftapemark.s_spcl.c_checksum = CHECKSUM - i;
232 	}
233 	if (vflag || command == 't')
234 		printdumpinfo();
235 	dumptime = _time64_to_time(spcl.c_ddate);
236 	dumpdate = _time64_to_time(spcl.c_date);
237 	if (stat(".", &stbuf) < 0) {
238 		fprintf(stderr, "cannot stat .: %s\n", strerror(errno));
239 		done(1);
240 	}
241 	if (stbuf.st_blksize > 0 && stbuf.st_blksize < TP_BSIZE )
242 		fssize = TP_BSIZE;
243 	if (stbuf.st_blksize >= TP_BSIZE && stbuf.st_blksize <= MAXBSIZE)
244 		fssize = stbuf.st_blksize;
245 	if (((fssize - 1) & fssize) != 0) {
246 		fprintf(stderr, "bad block size %ld\n", fssize);
247 		done(1);
248 	}
249 	if (spcl.c_volume != 1) {
250 		fprintf(stderr, "Tape is not volume 1 of the dump\n");
251 		done(1);
252 	}
253 	if (gethead(&spcl) == FAIL) {
254 		dprintf(stdout, "header read failed at %ld blocks\n", blksread);
255 		panic("no header after volume mark!\n");
256 	}
257 	findinode(&spcl);
258 	if (spcl.c_type != TS_CLRI) {
259 		fprintf(stderr, "Cannot find file removal list\n");
260 		done(1);
261 	}
262 	maxino = (spcl.c_count * TP_BSIZE * NBBY) + 1;
263 	dprintf(stdout, "maxino = %d\n", maxino);
264 	map = calloc((unsigned)1, (unsigned)howmany(maxino, NBBY));
265 	if (map == NULL)
266 		panic("no memory for active inode map\n");
267 	usedinomap = map;
268 	curfile.action = USING;
269 	getfile(xtrmap, xtrmapskip);
270 	if (spcl.c_type != TS_BITS) {
271 		fprintf(stderr, "Cannot find file dump list\n");
272 		done(1);
273 	}
274 	map = calloc((unsigned)1, (unsigned)howmany(maxino, NBBY));
275 	if (map == (char *)NULL)
276 		panic("no memory for file dump list\n");
277 	dumpmap = map;
278 	curfile.action = USING;
279 	getfile(xtrmap, xtrmapskip);
280 	/*
281 	 * If there may be whiteout entries on the tape, pretend that the
282 	 * whiteout inode exists, so that the whiteout entries can be
283 	 * extracted.
284 	 */
285 	SETINO(WINO, dumpmap);
286 	/* 'r' restores don't call getvol() for tape 1, so mark it as read. */
287 	if (command == 'r')
288 		tapesread = 1;
289 }
290 
291 /*
292  * Prompt user to load a new dump volume.
293  * "Nextvol" is the next suggested volume to use.
294  * This suggested volume is enforced when doing full
295  * or incremental restores, but can be overridden by
296  * the user when only extracting a subset of the files.
297  */
298 void
299 getvol(long nextvol)
300 {
301 	int64_t prevtapea;
302 	long i, newvol, savecnt;
303 	union u_spcl tmpspcl;
304 #	define tmpbuf tmpspcl.s_spcl
305 	char buf[TP_BSIZE];
306 
307 	if (nextvol == 1) {
308 		tapesread = 0;
309 		gettingfile = 0;
310 	}
311 	prevtapea = tapeaddr;
312 	savecnt = blksread;
313 	if (pipein) {
314 		if (nextvol != 1) {
315 			panic("Changing volumes on pipe input?\n");
316 			/* Avoid looping if we couldn't ask the user. */
317 			if (yflag || ferror(terminal) || feof(terminal))
318 				done(1);
319 		}
320 		if (volno == 1)
321 			return;
322 		if (pipecmdin) {
323 			closemt();
324 			goto getpipecmdhdr;
325 		}
326 		goto gethdr;
327 	}
328 again:
329 	if (pipein)
330 		done(1); /* pipes do not get a second chance */
331 	if (command == 'R' || command == 'r' || curfile.action != SKIP)
332 		newvol = nextvol;
333 	else
334 		newvol = 0;
335 	while (newvol <= 0) {
336 		if (tapesread == 0) {
337 			fprintf(stderr, "%s%s%s%s%s%s%s",
338 			    "You have not read any tapes yet.\n",
339 			    "If you are extracting just a few files,",
340 			    " start with the last volume\n",
341 			    "and work towards the first; restore",
342 			    " can quickly skip tapes that\n",
343 			    "have no further files to extract.",
344 			    " Otherwise, begin with volume 1.\n");
345 		} else {
346 			fprintf(stderr, "You have read volumes");
347 			strcpy(buf, ": ");
348 			for (i = 0; i < 32; i++)
349 				if (tapesread & (1 << i)) {
350 					fprintf(stderr, "%s%ld", buf, i + 1);
351 					strcpy(buf, ", ");
352 				}
353 			fprintf(stderr, "\n");
354 		}
355 		do	{
356 			fprintf(stderr, "Specify next volume #: ");
357 			(void) fflush(stderr);
358 			if (fgets(buf, BUFSIZ, terminal) == NULL)
359 				done(1);
360 		} while (buf[0] == '\n');
361 		newvol = atoi(buf);
362 		if (newvol <= 0) {
363 			fprintf(stderr,
364 			    "Volume numbers are positive numerics\n");
365 		}
366 	}
367 	if (newvol == volno) {
368 		tapesread |= 1 << (volno - 1);
369 		return;
370 	}
371 	closemt();
372 	fprintf(stderr, "Mount tape volume %ld\n", newvol);
373 	fprintf(stderr, "Enter ``none'' if there are no more tapes\n");
374 	fprintf(stderr, "otherwise enter tape name (default: %s) ", magtape);
375 	(void) fflush(stderr);
376 	if (fgets(buf, BUFSIZ, terminal) == NULL)
377 		done(1);
378 	if (!strcmp(buf, "none\n")) {
379 		terminateinput();
380 		return;
381 	}
382 	if (buf[0] != '\n') {
383 		(void) strcpy(magtape, buf);
384 		magtape[strlen(magtape) - 1] = '\0';
385 	}
386 	if (pipecmdin) {
387 		char volno[sizeof("2147483647")];
388 
389 getpipecmdhdr:
390 		(void)sprintf(volno, "%d", newvol);
391 		if (setenv("RESTORE_VOLUME", volno, 1) == -1) {
392 			fprintf(stderr, "Cannot set $RESTORE_VOLUME: %s\n",
393 			    strerror(errno));
394 			done(1);
395 		}
396 		popenfp = popen(magtape, "r");
397 		mt = popenfp ? fileno(popenfp) : -1;
398 	} else
399 #ifdef RRESTORE
400 	if (host)
401 		mt = rmtopen(magtape, 0);
402 	else
403 #endif
404 		mt = open(magtape, O_RDONLY, 0);
405 
406 	if (mt == -1) {
407 		fprintf(stderr, "Cannot open %s\n", magtape);
408 		volno = -1;
409 		goto again;
410 	}
411 gethdr:
412 	volno = newvol;
413 	setdumpnum();
414 	FLUSHTAPEBUF();
415 	if (gethead(&tmpbuf) == FAIL) {
416 		dprintf(stdout, "header read failed at %ld blocks\n", blksread);
417 		fprintf(stderr, "tape is not dump tape\n");
418 		volno = 0;
419 		goto again;
420 	}
421 	if (tmpbuf.c_volume != volno) {
422 		fprintf(stderr, "Wrong volume (%ld)\n", tmpbuf.c_volume);
423 		volno = 0;
424 		goto again;
425 	}
426 	if (_time64_to_time(tmpbuf.c_date) != dumpdate ||
427 	    _time64_to_time(tmpbuf.c_ddate) != dumptime) {
428 		time_t t = _time64_to_time(tmpbuf.c_date);
429 		fprintf(stderr, "Wrong dump date\n\tgot: %s", ctime(&t));
430 		fprintf(stderr, "\twanted: %s", ctime(&dumpdate));
431 		volno = 0;
432 		goto again;
433 	}
434 	tapesread |= 1 << (volno - 1);
435 	blksread = savecnt;
436  	/*
437  	 * If continuing from the previous volume, skip over any
438  	 * blocks read already at the end of the previous volume.
439  	 *
440  	 * If coming to this volume at random, skip to the beginning
441  	 * of the next record.
442  	 */
443 	dprintf(stdout, "last rec %qd, tape starts with %qd\n", prevtapea,
444 	    tmpbuf.c_tapea);
445  	if (tmpbuf.c_type == TS_TAPE) {
446  		if (curfile.action != USING) {
447 			/*
448 			 * XXX Dump incorrectly sets c_count to 1 in the
449 			 * volume header of the first tape, so ignore
450 			 * c_count when volno == 1.
451 			 */
452 			if (volno != 1)
453 				for (i = tmpbuf.c_count; i > 0; i--)
454 					readtape(buf);
455  		} else if (tmpbuf.c_tapea <= prevtapea) {
456 			/*
457 			 * Normally the value of c_tapea in the volume
458 			 * header is the record number of the header itself.
459 			 * However in the volume header following an EOT-
460 			 * terminated tape, it is the record number of the
461 			 * first continuation data block (dump bug?).
462 			 *
463 			 * The next record we want is `prevtapea + 1'.
464 			 */
465  			i = prevtapea + 1 - tmpbuf.c_tapea;
466 			dprintf(stderr, "Skipping %ld duplicate record%s.\n",
467 				i, i > 1 ? "s" : "");
468  			while (--i >= 0)
469  				readtape(buf);
470  		}
471  	}
472 	if (curfile.action == USING) {
473 		if (volno == 1)
474 			panic("active file into volume 1\n");
475 		return;
476 	}
477 	(void) gethead(&spcl);
478 	findinode(&spcl);
479 	if (gettingfile) {
480 		gettingfile = 0;
481 		longjmp(restart, 1);
482 	}
483 }
484 
485 /*
486  * Handle unexpected EOF.
487  */
488 static void
489 terminateinput(void)
490 {
491 
492 	if (gettingfile && curfile.action == USING) {
493 		printf("Warning: %s %s\n",
494 		    "End-of-input encountered while extracting", curfile.name);
495 	}
496 	curfile.name = "<name unknown>";
497 	curfile.action = UNKNOWN;
498 	curfile.mode = 0;
499 	curfile.ino = maxino;
500 	if (gettingfile) {
501 		gettingfile = 0;
502 		longjmp(restart, 1);
503 	}
504 }
505 
506 /*
507  * handle multiple dumps per tape by skipping forward to the
508  * appropriate one.
509  */
510 static void
511 setdumpnum(void)
512 {
513 	struct mtop tcom;
514 
515 	if (dumpnum == 1 || volno != 1)
516 		return;
517 	if (pipein) {
518 		fprintf(stderr, "Cannot have multiple dumps on pipe input\n");
519 		done(1);
520 	}
521 	tcom.mt_op = MTFSF;
522 	tcom.mt_count = dumpnum - 1;
523 #ifdef RRESTORE
524 	if (host)
525 		rmtioctl(MTFSF, dumpnum - 1);
526 	else
527 #endif
528 		if (!pipecmdin && ioctl(mt, MTIOCTOP, (char *)&tcom) < 0)
529 			fprintf(stderr, "ioctl MTFSF: %s\n", strerror(errno));
530 }
531 
532 void
533 printdumpinfo(void)
534 {
535 	time_t t;
536 	t = _time64_to_time(spcl.c_date);
537 	fprintf(stdout, "Dump   date: %s", ctime(&t));
538 	t = _time64_to_time(spcl.c_ddate);
539 	fprintf(stdout, "Dumped from: %s",
540 	    (spcl.c_ddate == 0) ? "the epoch\n" : ctime(&t));
541 	if (spcl.c_host[0] == '\0')
542 		return;
543 	fprintf(stderr, "Level %ld dump of %s on %s:%s\n",
544 		spcl.c_level, spcl.c_filesys, spcl.c_host, spcl.c_dev);
545 	fprintf(stderr, "Label: %s\n", spcl.c_label);
546 }
547 
548 int
549 extractfile(char *name)
550 {
551 	int flags;
552 	mode_t mode;
553 	struct timeval mtimep[2], ctimep[2];
554 	struct entry *ep;
555 
556 	curfile.name = name;
557 	curfile.action = USING;
558 	mtimep[0].tv_sec = curfile.atime_sec;
559 	mtimep[0].tv_usec = curfile.atime_nsec / 1000;
560 	mtimep[1].tv_sec = curfile.mtime_sec;
561 	mtimep[1].tv_usec = curfile.mtime_nsec / 1000;
562 	ctimep[0].tv_sec = curfile.atime_sec;
563 	ctimep[0].tv_usec = curfile.atime_nsec / 1000;
564 	ctimep[1].tv_sec = curfile.birthtime_sec;
565 	ctimep[1].tv_usec = curfile.birthtime_nsec / 1000;
566 	mode = curfile.mode;
567 	flags = curfile.file_flags;
568 	switch (mode & IFMT) {
569 
570 	default:
571 		fprintf(stderr, "%s: unknown file mode 0%o\n", name, mode);
572 		skipfile();
573 		return (FAIL);
574 
575 	case IFSOCK:
576 		vprintf(stdout, "skipped socket %s\n", name);
577 		skipfile();
578 		return (GOOD);
579 
580 	case IFDIR:
581 		if (mflag) {
582 			ep = lookupname(name);
583 			if (ep == NULL || ep->e_flags & EXTRACT)
584 				panic("unextracted directory %s\n", name);
585 			skipfile();
586 			return (GOOD);
587 		}
588 		vprintf(stdout, "extract file %s\n", name);
589 		return (genliteraldir(name, curfile.ino));
590 
591 	case IFLNK:
592 		lnkbuf[0] = '\0';
593 		pathlen = 0;
594 		getfile(xtrlnkfile, xtrlnkskip);
595 		if (pathlen == 0) {
596 			vprintf(stdout,
597 			    "%s: zero length symbolic link (ignored)\n", name);
598 			return (GOOD);
599 		}
600 		if (linkit(lnkbuf, name, SYMLINK) == GOOD) {
601 			(void) lchown(name, curfile.uid, curfile.gid);
602 			(void) lchmod(name, mode);
603 			(void) lutimes(name, ctimep);
604 			(void) lutimes(name, mtimep);
605 			return (GOOD);
606 		}
607 		return (FAIL);
608 
609 	case IFIFO:
610 		vprintf(stdout, "extract fifo %s\n", name);
611 		if (Nflag) {
612 			skipfile();
613 			return (GOOD);
614 		}
615 		if (uflag && !Nflag)
616 			(void)unlink(name);
617 		if (mkfifo(name, mode) < 0) {
618 			fprintf(stderr, "%s: cannot create fifo: %s\n",
619 			    name, strerror(errno));
620 			skipfile();
621 			return (FAIL);
622 		}
623 		(void) chown(name, curfile.uid, curfile.gid);
624 		(void) chmod(name, mode);
625 		(void) utimes(name, ctimep);
626 		(void) utimes(name, mtimep);
627 		(void) chflags(name, flags);
628 		skipfile();
629 		return (GOOD);
630 
631 	case IFCHR:
632 	case IFBLK:
633 		vprintf(stdout, "extract special file %s\n", name);
634 		if (Nflag) {
635 			skipfile();
636 			return (GOOD);
637 		}
638 		if (uflag)
639 			(void)unlink(name);
640 		if (mknod(name, mode, (int)curfile.rdev) < 0) {
641 			fprintf(stderr, "%s: cannot create special file: %s\n",
642 			    name, strerror(errno));
643 			skipfile();
644 			return (FAIL);
645 		}
646 		(void) chown(name, curfile.uid, curfile.gid);
647 		(void) chmod(name, mode);
648 		(void) utimes(name, ctimep);
649 		(void) utimes(name, mtimep);
650 		(void) chflags(name, flags);
651 		skipfile();
652 		return (GOOD);
653 
654 	case IFREG:
655 		vprintf(stdout, "extract file %s\n", name);
656 		if (Nflag) {
657 			skipfile();
658 			return (GOOD);
659 		}
660 		if (uflag)
661 			(void)unlink(name);
662 		if ((ofile = open(name, O_WRONLY | O_CREAT | O_TRUNC,
663 		    0666)) < 0) {
664 			fprintf(stderr, "%s: cannot create file: %s\n",
665 			    name, strerror(errno));
666 			skipfile();
667 			return (FAIL);
668 		}
669 		(void) fchown(ofile, curfile.uid, curfile.gid);
670 		(void) fchmod(ofile, mode);
671 		getfile(xtrfile, xtrskip);
672 		(void) close(ofile);
673 		(void) utimes(name, ctimep);
674 		(void) utimes(name, mtimep);
675 		(void) chflags(name, flags);
676 		return (GOOD);
677 	}
678 	/* NOTREACHED */
679 }
680 
681 /*
682  * skip over bit maps on the tape
683  */
684 void
685 skipmaps(void)
686 {
687 
688 	while (spcl.c_type == TS_BITS || spcl.c_type == TS_CLRI)
689 		skipfile();
690 }
691 
692 /*
693  * skip over a file on the tape
694  */
695 void
696 skipfile(void)
697 {
698 
699 	curfile.action = SKIP;
700 	getfile(xtrnull, xtrnull);
701 }
702 
703 /*
704  * Extract a file from the tape.
705  * When an allocated block is found it is passed to the fill function;
706  * when an unallocated block (hole) is found, a zeroed buffer is passed
707  * to the skip function.
708  */
709 void
710 getfile(void (*fill)(char *, long), void (*skip)(char *, long))
711 {
712 	int i;
713 	int curblk = 0;
714 	quad_t size = spcl.c_size;
715 	static char clearedbuf[MAXBSIZE];
716 	char buf[MAXBSIZE / TP_BSIZE][TP_BSIZE];
717 	char junk[TP_BSIZE];
718 
719 	if (spcl.c_type == TS_END)
720 		panic("ran off end of tape\n");
721 	if (spcl.c_magic != FS_UFS2_MAGIC)
722 		panic("not at beginning of a file\n");
723 	if (!gettingfile && setjmp(restart) != 0)
724 		return;
725 	gettingfile++;
726 loop:
727 	for (i = 0; i < spcl.c_count; i++) {
728 		if (readmapflag || spcl.c_addr[i]) {
729 			readtape(&buf[curblk++][0]);
730 			if (curblk == fssize / TP_BSIZE) {
731 				(*fill)((char *)buf, (long)(size > TP_BSIZE ?
732 				     fssize : (curblk - 1) * TP_BSIZE + size));
733 				curblk = 0;
734 			}
735 		} else {
736 			if (curblk > 0) {
737 				(*fill)((char *)buf, (long)(size > TP_BSIZE ?
738 				     curblk * TP_BSIZE :
739 				     (curblk - 1) * TP_BSIZE + size));
740 				curblk = 0;
741 			}
742 			(*skip)(clearedbuf, (long)(size > TP_BSIZE ?
743 				TP_BSIZE : size));
744 		}
745 		if ((size -= TP_BSIZE) <= 0) {
746 			for (i++; i < spcl.c_count; i++)
747 				if (readmapflag || spcl.c_addr[i])
748 					readtape(junk);
749 			break;
750 		}
751 	}
752 	if (gethead(&spcl) == GOOD && size > 0) {
753 		if (spcl.c_type == TS_ADDR)
754 			goto loop;
755 		dprintf(stdout,
756 			"Missing address (header) block for %s at %ld blocks\n",
757 			curfile.name, blksread);
758 	}
759 	if (curblk > 0)
760 		(*fill)((char *)buf, (long)((curblk * TP_BSIZE) + size));
761 	findinode(&spcl);
762 	gettingfile = 0;
763 }
764 
765 /*
766  * Write out the next block of a file.
767  */
768 static void
769 xtrfile(char *buf, long	size)
770 {
771 
772 	if (Nflag)
773 		return;
774 	if (write(ofile, buf, (int) size) == -1) {
775 		fprintf(stderr,
776 		    "write error extracting inode %d, name %s\nwrite: %s\n",
777 			curfile.ino, curfile.name, strerror(errno));
778 	}
779 }
780 
781 /*
782  * Skip over a hole in a file.
783  */
784 /* ARGSUSED */
785 static void
786 xtrskip(char *buf, long size)
787 {
788 
789 	if (lseek(ofile, size, SEEK_CUR) == -1) {
790 		fprintf(stderr,
791 		    "seek error extracting inode %d, name %s\nlseek: %s\n",
792 			curfile.ino, curfile.name, strerror(errno));
793 		done(1);
794 	}
795 }
796 
797 /*
798  * Collect the next block of a symbolic link.
799  */
800 static void
801 xtrlnkfile(char *buf, long size)
802 {
803 
804 	pathlen += size;
805 	if (pathlen > MAXPATHLEN) {
806 		fprintf(stderr, "symbolic link name: %s->%s%s; too long %d\n",
807 		    curfile.name, lnkbuf, buf, pathlen);
808 		done(1);
809 	}
810 	(void) strcat(lnkbuf, buf);
811 }
812 
813 /*
814  * Skip over a hole in a symbolic link (should never happen).
815  */
816 /* ARGSUSED */
817 static void
818 xtrlnkskip(char *buf, long size)
819 {
820 
821 	fprintf(stderr, "unallocated block in symbolic link %s\n",
822 		curfile.name);
823 	done(1);
824 }
825 
826 /*
827  * Collect the next block of a bit map.
828  */
829 static void
830 xtrmap(char *buf, long size)
831 {
832 
833 	memmove(map, buf, size);
834 	map += size;
835 }
836 
837 /*
838  * Skip over a hole in a bit map (should never happen).
839  */
840 /* ARGSUSED */
841 static void
842 xtrmapskip(char *buf, long size)
843 {
844 
845 	panic("hole in map\n");
846 	map += size;
847 }
848 
849 /*
850  * Noop, when an extraction function is not needed.
851  */
852 /* ARGSUSED */
853 void
854 xtrnull(char *buf, long size)
855 {
856 
857 	return;
858 }
859 
860 /*
861  * Read TP_BSIZE blocks from the input.
862  * Handle read errors, and end of media.
863  */
864 static void
865 readtape(char *buf)
866 {
867 	long rd, newvol, i;
868 	int cnt, seek_failed;
869 
870 	if (blkcnt < numtrec) {
871 		memmove(buf, &tapebuf[(blkcnt++ * TP_BSIZE)], (long)TP_BSIZE);
872 		blksread++;
873 		tapeaddr++;
874 		return;
875 	}
876 	for (i = 0; i < ntrec; i++)
877 		((struct s_spcl *)&tapebuf[i * TP_BSIZE])->c_magic = 0;
878 	if (numtrec == 0)
879 		numtrec = ntrec;
880 	cnt = ntrec * TP_BSIZE;
881 	rd = 0;
882 getmore:
883 #ifdef RRESTORE
884 	if (host)
885 		i = rmtread(&tapebuf[rd], cnt);
886 	else
887 #endif
888 		i = read(mt, &tapebuf[rd], cnt);
889 	/*
890 	 * Check for mid-tape short read error.
891 	 * If found, skip rest of buffer and start with the next.
892 	 */
893 	if (!pipein && numtrec < ntrec && i > 0) {
894 		dprintf(stdout, "mid-media short read error.\n");
895 		numtrec = ntrec;
896 	}
897 	/*
898 	 * Handle partial block read.
899 	 */
900 	if (pipein && i == 0 && rd > 0)
901 		i = rd;
902 	else if (i > 0 && i != ntrec * TP_BSIZE) {
903 		if (pipein) {
904 			rd += i;
905 			cnt -= i;
906 			if (cnt > 0)
907 				goto getmore;
908 			i = rd;
909 		} else {
910 			/*
911 			 * Short read. Process the blocks read.
912 			 */
913 			if (i % TP_BSIZE != 0)
914 				vprintf(stdout,
915 				    "partial block read: %ld should be %ld\n",
916 				    i, ntrec * TP_BSIZE);
917 			numtrec = i / TP_BSIZE;
918 		}
919 	}
920 	/*
921 	 * Handle read error.
922 	 */
923 	if (i < 0) {
924 		fprintf(stderr, "Tape read error while ");
925 		switch (curfile.action) {
926 		default:
927 			fprintf(stderr, "trying to set up tape\n");
928 			break;
929 		case UNKNOWN:
930 			fprintf(stderr, "trying to resynchronize\n");
931 			break;
932 		case USING:
933 			fprintf(stderr, "restoring %s\n", curfile.name);
934 			break;
935 		case SKIP:
936 			fprintf(stderr, "skipping over inode %d\n",
937 				curfile.ino);
938 			break;
939 		}
940 		if (!yflag && !reply("continue"))
941 			done(1);
942 		i = ntrec * TP_BSIZE;
943 		memset(tapebuf, 0, i);
944 #ifdef RRESTORE
945 		if (host)
946 			seek_failed = (rmtseek(i, 1) < 0);
947 		else
948 #endif
949 			seek_failed = (lseek(mt, i, SEEK_CUR) == (off_t)-1);
950 
951 		if (seek_failed) {
952 			fprintf(stderr,
953 			    "continuation failed: %s\n", strerror(errno));
954 			done(1);
955 		}
956 	}
957 	/*
958 	 * Handle end of tape.
959 	 */
960 	if (i == 0) {
961 		vprintf(stdout, "End-of-tape encountered\n");
962 		if (!pipein) {
963 			newvol = volno + 1;
964 			volno = 0;
965 			numtrec = 0;
966 			getvol(newvol);
967 			readtape(buf);
968 			return;
969 		}
970 		if (rd % TP_BSIZE != 0)
971 			panic("partial block read: %d should be %d\n",
972 				rd, ntrec * TP_BSIZE);
973 		terminateinput();
974 		memmove(&tapebuf[rd], &endoftapemark, (long)TP_BSIZE);
975 	}
976 	blkcnt = 0;
977 	memmove(buf, &tapebuf[(blkcnt++ * TP_BSIZE)], (long)TP_BSIZE);
978 	blksread++;
979 	tapeaddr++;
980 }
981 
982 static void
983 findtapeblksize(void)
984 {
985 	long i;
986 
987 	for (i = 0; i < ntrec; i++)
988 		((struct s_spcl *)&tapebuf[i * TP_BSIZE])->c_magic = 0;
989 	blkcnt = 0;
990 #ifdef RRESTORE
991 	if (host)
992 		i = rmtread(tapebuf, ntrec * TP_BSIZE);
993 	else
994 #endif
995 		i = read(mt, tapebuf, ntrec * TP_BSIZE);
996 
997 	if (i <= 0) {
998 		fprintf(stderr, "tape read error: %s\n", strerror(errno));
999 		done(1);
1000 	}
1001 	if (i % TP_BSIZE != 0) {
1002 		fprintf(stderr, "Tape block size (%ld) %s (%d)\n",
1003 			i, "is not a multiple of dump block size", TP_BSIZE);
1004 		done(1);
1005 	}
1006 	ntrec = i / TP_BSIZE;
1007 	numtrec = ntrec;
1008 	vprintf(stdout, "Tape block size is %ld\n", ntrec);
1009 }
1010 
1011 void
1012 closemt(void)
1013 {
1014 
1015 	if (mt < 0)
1016 		return;
1017 	if (pipecmdin) {
1018 		pclose(popenfp);
1019 		popenfp = NULL;
1020 	} else
1021 #ifdef RRESTORE
1022 	if (host)
1023 		rmtclose();
1024 	else
1025 #endif
1026 		(void) close(mt);
1027 }
1028 
1029 /*
1030  * Read the next block from the tape.
1031  * If it is not any valid header, return an error.
1032  */
1033 static int
1034 gethead(struct s_spcl *buf)
1035 {
1036 	long i;
1037 
1038 	readtape((char *)buf);
1039 	if (buf->c_magic != FS_UFS2_MAGIC && buf->c_magic != NFS_MAGIC) {
1040 		if (buf->c_magic == OFS_MAGIC) {
1041 			fprintf(stderr,
1042 			    "Format of dump tape is too old. Must use\n");
1043 			fprintf(stderr,
1044 			    "a version of restore from before 2002.\n");
1045 			return (FAIL);
1046 		}
1047 		if (swabl(buf->c_magic) != FS_UFS2_MAGIC &&
1048 		    buf->c_magic != NFS_MAGIC) {
1049 			if (buf->c_magic == OFS_MAGIC) {
1050 				fprintf(stderr,
1051 				  "Format of dump tape is too old. Must use\n");
1052 				fprintf(stderr,
1053 				  "a version of restore from before 2002.\n");
1054 			}
1055 			return (FAIL);
1056 		}
1057 		if (!Bcvt) {
1058 			vprintf(stdout, "Note: Doing Byte swapping\n");
1059 			Bcvt = 1;
1060 		}
1061 	}
1062 	if (checksum((int *)buf) == FAIL)
1063 		return (FAIL);
1064 	if (Bcvt) {
1065 		swabst((u_char *)"8l4s1q8l2q17l", (u_char *)buf);
1066 		swabst((u_char *)"l",(u_char *) &buf->c_level);
1067 		swabst((u_char *)"2l4q",(u_char *) &buf->c_flags);
1068 	}
1069 	readmapflag = 0;
1070 
1071 	switch (buf->c_type) {
1072 
1073 	case TS_CLRI:
1074 	case TS_BITS:
1075 		/*
1076 		 * Have to patch up missing information in bit map headers
1077 		 */
1078 		buf->c_inumber = 0;
1079 		buf->c_size = buf->c_count * TP_BSIZE;
1080 		if (buf->c_count > TP_NINDIR)
1081 			readmapflag = 1;
1082 		else
1083 			for (i = 0; i < buf->c_count; i++)
1084 				buf->c_addr[i]++;
1085 		break;
1086 
1087 	case TS_TAPE:
1088 	case TS_END:
1089 		buf->c_inumber = 0;
1090 		break;
1091 
1092 	case TS_INODE:
1093 		/*
1094 		 * For old dump tapes, have to copy up old fields to
1095 		 * new locations.
1096 		 */
1097 		if (buf->c_magic == NFS_MAGIC) {
1098 			buf->c_tapea = buf->c_old_tapea;
1099 			buf->c_firstrec = buf->c_old_firstrec;
1100 			buf->c_date = _time32_to_time(buf->c_old_date);
1101 			buf->c_ddate = _time32_to_time(buf->c_old_ddate);
1102 			buf->c_atime = _time32_to_time(buf->c_old_atime);
1103 			buf->c_mtime = _time32_to_time(buf->c_old_mtime);
1104 		}
1105 		break;
1106 
1107 	case TS_ADDR:
1108 		break;
1109 
1110 	default:
1111 		panic("gethead: unknown inode type %d\n", buf->c_type);
1112 		break;
1113 	}
1114 	buf->c_magic = FS_UFS2_MAGIC;
1115 	tapeaddr = buf->c_tapea;
1116 	if (dflag)
1117 		accthdr(buf);
1118 	return(GOOD);
1119 }
1120 
1121 /*
1122  * Check that a header is where it belongs and predict the next header
1123  */
1124 static void
1125 accthdr(struct s_spcl *header)
1126 {
1127 	static ino_t previno = 0x7fffffff;
1128 	static int prevtype;
1129 	static long predict;
1130 	long blks, i;
1131 
1132 	if (header->c_type == TS_TAPE) {
1133 		fprintf(stderr, "Volume header ");
1134  		if (header->c_firstrec)
1135  			fprintf(stderr, "begins with record %qd",
1136  				header->c_firstrec);
1137  		fprintf(stderr, "\n");
1138 		previno = 0x7fffffff;
1139 		return;
1140 	}
1141 	if (previno == 0x7fffffff)
1142 		goto newcalc;
1143 	switch (prevtype) {
1144 	case TS_BITS:
1145 		fprintf(stderr, "Dumped inodes map header");
1146 		break;
1147 	case TS_CLRI:
1148 		fprintf(stderr, "Used inodes map header");
1149 		break;
1150 	case TS_INODE:
1151 		fprintf(stderr, "File header, ino %d", previno);
1152 		break;
1153 	case TS_ADDR:
1154 		fprintf(stderr, "File continuation header, ino %d", previno);
1155 		break;
1156 	case TS_END:
1157 		fprintf(stderr, "End of tape header");
1158 		break;
1159 	}
1160 	if (predict != blksread - 1)
1161 		fprintf(stderr, "; predicted %ld blocks, got %ld blocks",
1162 			predict, blksread - 1);
1163 	fprintf(stderr, "\n");
1164 newcalc:
1165 	blks = 0;
1166 	if (header->c_type != TS_END)
1167 		for (i = 0; i < header->c_count; i++)
1168 			if (readmapflag || header->c_addr[i] != 0)
1169 				blks++;
1170 	predict = blks;
1171 	blksread = 0;
1172 	prevtype = header->c_type;
1173 	previno = header->c_inumber;
1174 }
1175 
1176 /*
1177  * Find an inode header.
1178  * Complain if had to skip.
1179  */
1180 static void
1181 findinode(struct s_spcl *header)
1182 {
1183 	static long skipcnt = 0;
1184 	long i;
1185 	char buf[TP_BSIZE];
1186 	int htype;
1187 
1188 	curfile.name = "<name unknown>";
1189 	curfile.action = UNKNOWN;
1190 	curfile.mode = 0;
1191 	curfile.ino = 0;
1192 	do {
1193 		htype = header->c_type;
1194 		switch (htype) {
1195 
1196 		case TS_ADDR:
1197 			/*
1198 			 * Skip up to the beginning of the next record
1199 			 */
1200 			for (i = 0; i < header->c_count; i++)
1201 				if (header->c_addr[i])
1202 					readtape(buf);
1203 			while (gethead(header) == FAIL ||
1204 			    _time64_to_time(header->c_date) != dumpdate)
1205 				skipcnt++;
1206 			break;
1207 
1208 		case TS_INODE:
1209 			curfile.mode = header->c_mode;
1210 			curfile.uid = header->c_uid;
1211 			curfile.gid = header->c_gid;
1212 			curfile.file_flags = header->c_file_flags;
1213 			curfile.rdev = header->c_rdev;
1214 			curfile.atime_sec = header->c_atime;
1215 			curfile.atime_nsec = header->c_atimensec;
1216 			curfile.mtime_sec = header->c_mtime;
1217 			curfile.mtime_nsec = header->c_mtimensec;
1218 			curfile.birthtime_sec = header->c_birthtime;
1219 			curfile.birthtime_nsec = header->c_birthtimensec;
1220 			curfile.size = header->c_size;
1221 			curfile.ino = header->c_inumber;
1222 			break;
1223 
1224 		case TS_END:
1225 			/* If we missed some tapes, get another volume. */
1226 			if (tapesread & (tapesread + 1)) {
1227 				getvol(0);
1228 				continue;
1229 			}
1230 			curfile.ino = maxino;
1231 			break;
1232 
1233 		case TS_CLRI:
1234 			curfile.name = "<file removal list>";
1235 			break;
1236 
1237 		case TS_BITS:
1238 			curfile.name = "<file dump list>";
1239 			break;
1240 
1241 		case TS_TAPE:
1242 			panic("unexpected tape header\n");
1243 			/* NOTREACHED */
1244 
1245 		default:
1246 			panic("unknown tape header type %d\n", spcl.c_type);
1247 			/* NOTREACHED */
1248 
1249 		}
1250 	} while (htype == TS_ADDR);
1251 	if (skipcnt > 0)
1252 		fprintf(stderr, "resync restore, skipped %ld blocks\n",
1253 		    skipcnt);
1254 	skipcnt = 0;
1255 }
1256 
1257 static int
1258 checksum(int *buf)
1259 {
1260 	int i, j;
1261 
1262 	j = sizeof(union u_spcl) / sizeof(int);
1263 	i = 0;
1264 	if (!Bcvt) {
1265 		do
1266 			i += *buf++;
1267 		while (--j);
1268 	} else {
1269 		/* What happens if we want to read restore tapes
1270 			for a 16bit int machine??? */
1271 		do
1272 			i += swabl(*buf++);
1273 		while (--j);
1274 	}
1275 
1276 	if (i != CHECKSUM) {
1277 		fprintf(stderr, "Checksum error %o, inode %d file %s\n", i,
1278 			curfile.ino, curfile.name);
1279 		return(FAIL);
1280 	}
1281 	return(GOOD);
1282 }
1283 
1284 #ifdef RRESTORE
1285 #include <stdarg.h>
1286 
1287 void
1288 msg(const char *fmt, ...)
1289 {
1290 	va_list ap;
1291 	va_start(ap, fmt);
1292 	(void)vfprintf(stderr, fmt, ap);
1293 	va_end(ap);
1294 }
1295 #endif /* RRESTORE */
1296 
1297 static u_char *
1298 swabshort(u_char *sp, int n)
1299 {
1300 	char c;
1301 
1302 	while (--n >= 0) {
1303 		c = sp[0]; sp[0] = sp[1]; sp[1] = c;
1304 		sp += 2;
1305 	}
1306 	return (sp);
1307 }
1308 
1309 static u_char *
1310 swablong(u_char *sp, int n)
1311 {
1312 	char c;
1313 
1314 	while (--n >= 0) {
1315 		c = sp[0]; sp[0] = sp[3]; sp[3] = c;
1316 		c = sp[2]; sp[2] = sp[1]; sp[1] = c;
1317 		sp += 4;
1318 	}
1319 	return (sp);
1320 }
1321 
1322 static u_char *
1323 swabquad(u_char *sp, int n)
1324 {
1325 	char c;
1326 
1327 	while (--n >= 0) {
1328 		c = sp[0]; sp[0] = sp[7]; sp[7] = c;
1329 		c = sp[1]; sp[1] = sp[6]; sp[6] = c;
1330 		c = sp[2]; sp[2] = sp[5]; sp[5] = c;
1331 		c = sp[3]; sp[3] = sp[4]; sp[4] = c;
1332 		sp += 8;
1333 	}
1334 	return (sp);
1335 }
1336 
1337 void
1338 swabst(u_char *cp, u_char *sp)
1339 {
1340 	int n = 0;
1341 
1342 	while (*cp) {
1343 		switch (*cp) {
1344 		case '0': case '1': case '2': case '3': case '4':
1345 		case '5': case '6': case '7': case '8': case '9':
1346 			n = (n * 10) + (*cp++ - '0');
1347 			continue;
1348 
1349 		case 's': case 'w': case 'h':
1350 			if (n == 0)
1351 				n = 1;
1352 			sp = swabshort(sp, n);
1353 			break;
1354 
1355 		case 'l':
1356 			if (n == 0)
1357 				n = 1;
1358 			sp = swablong(sp, n);
1359 			break;
1360 
1361 		case 'q':
1362 			if (n == 0)
1363 				n = 1;
1364 			sp = swabquad(sp, n);
1365 			break;
1366 
1367 		case 'b':
1368 			if (n == 0)
1369 				n = 1;
1370 			sp += n;
1371 			break;
1372 
1373 		default:
1374 			fprintf(stderr, "Unknown conversion character: %c\n",
1375 			    *cp);
1376 			done(0);
1377 			break;
1378 		}
1379 		cp++;
1380 		n = 0;
1381 	}
1382 }
1383 
1384 static u_long
1385 swabl(u_long x)
1386 {
1387 	swabst((u_char *)"l", (u_char *)&x);
1388 	return (x);
1389 }
1390