xref: /freebsd/sbin/restore/tape.c (revision b52b9d56d4e96089873a75f9e29062eec19fabba)
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  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the University of
21  *	California, Berkeley and its contributors.
22  * 4. Neither the name of the University nor the names of its contributors
23  *    may be used to endorse or promote products derived from this software
24  *    without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36  * SUCH DAMAGE.
37  */
38 
39 #ifndef lint
40 #if 0
41 static char sccsid[] = "@(#)tape.c	8.9 (Berkeley) 5/1/95";
42 #endif
43 static const char rcsid[] =
44   "$FreeBSD$";
45 #endif /* not lint */
46 
47 #include <sys/param.h>
48 #include <sys/file.h>
49 #include <sys/mtio.h>
50 #include <sys/stat.h>
51 #include <sys/time.h>
52 
53 #include <ufs/ufs/dinode.h>
54 #include <protocols/dumprestore.h>
55 
56 #include <errno.h>
57 #include <paths.h>
58 #include <setjmp.h>
59 #include <stdio.h>
60 #include <stdlib.h>
61 #include <string.h>
62 #include <time.h>
63 #include <unistd.h>
64 
65 #include "restore.h"
66 #include "extern.h"
67 
68 static long	fssize = MAXBSIZE;
69 static int	mt = -1;
70 static int	pipein = 0;
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)
116 {
117 	FLUSHTAPEBUF();
118 	if (bflag)
119 		newtapebuf(ntrec);
120 	else
121 		newtapebuf(NTREC > HIGHDENSITYTREC ? NTREC : HIGHDENSITYTREC);
122 	terminal = stdin;
123 
124 #ifdef RRESTORE
125 	if (strchr(source, ':')) {
126 		host = source;
127 		source = strchr(host, ':');
128 		*source++ = '\0';
129 		if (rmthost(host) == 0)
130 			done(1);
131 	} else
132 #endif
133 	if (strcmp(source, "-") == 0) {
134 		/*
135 		 * Since input is coming from a pipe we must establish
136 		 * our own connection to the terminal.
137 		 */
138 		terminal = fopen(_PATH_TTY, "r");
139 		if (terminal == NULL) {
140 			(void)fprintf(stderr, "cannot open %s: %s\n",
141 			    _PATH_TTY, strerror(errno));
142 			terminal = fopen(_PATH_DEVNULL, "r");
143 			if (terminal == NULL) {
144 				(void)fprintf(stderr, "cannot open %s: %s\n",
145 				    _PATH_DEVNULL, strerror(errno));
146 				done(1);
147 			}
148 		}
149 		pipein++;
150 	}
151 	setuid(getuid());	/* no longer need or want root privileges */
152 	magtape = strdup(source);
153 	if (magtape == NULL) {
154 		fprintf(stderr, "Cannot allocate space for magtape buffer\n");
155 		done(1);
156 	}
157 }
158 
159 void
160 newtapebuf(long size)
161 {
162 	static int tapebufsize = -1;
163 
164 	ntrec = size;
165 	if (size <= tapebufsize)
166 		return;
167 	if (tapebuf != NULL)
168 		free(tapebuf);
169 	tapebuf = malloc(size * TP_BSIZE);
170 	if (tapebuf == NULL) {
171 		fprintf(stderr, "Cannot allocate space for tape buffer\n");
172 		done(1);
173 	}
174 	tapebufsize = size;
175 }
176 
177 /*
178  * Verify that the tape drive can be accessed and
179  * that it actually is a dump tape.
180  */
181 void
182 setup(void)
183 {
184 	int i, j, *ip;
185 	struct stat stbuf;
186 
187 	vprintf(stdout, "Verify tape and initialize maps\n");
188 #ifdef RRESTORE
189 	if (host)
190 		mt = rmtopen(magtape, 0);
191 	else
192 #endif
193 	if (pipein)
194 		mt = 0;
195 	else
196 		mt = open(magtape, O_RDONLY, 0);
197 	if (mt < 0) {
198 		fprintf(stderr, "%s: %s\n", magtape, strerror(errno));
199 		done(1);
200 	}
201 	volno = 1;
202 	setdumpnum();
203 	FLUSHTAPEBUF();
204 	if (!pipein && !bflag)
205 		findtapeblksize();
206 	if (gethead(&spcl) == FAIL) {
207 		fprintf(stderr, "Tape is not a dump tape\n");
208 		done(1);
209 	}
210 	if (pipein) {
211 		endoftapemark.s_spcl.c_magic = FS_UFS2_MAGIC;
212 		endoftapemark.s_spcl.c_type = TS_END;
213 		ip = (int *)&endoftapemark;
214 		j = sizeof(union u_spcl) / sizeof(int);
215 		i = 0;
216 		do
217 			i += *ip++;
218 		while (--j);
219 		endoftapemark.s_spcl.c_checksum = CHECKSUM - i;
220 	}
221 	if (vflag || command == 't')
222 		printdumpinfo();
223 	dumptime = _time64_to_time(spcl.c_ddate);
224 	dumpdate = _time64_to_time(spcl.c_date);
225 	if (stat(".", &stbuf) < 0) {
226 		fprintf(stderr, "cannot stat .: %s\n", strerror(errno));
227 		done(1);
228 	}
229 	if (stbuf.st_blksize > 0 && stbuf.st_blksize < TP_BSIZE )
230 		fssize = TP_BSIZE;
231 	if (stbuf.st_blksize >= TP_BSIZE && stbuf.st_blksize <= MAXBSIZE)
232 		fssize = stbuf.st_blksize;
233 	if (((fssize - 1) & fssize) != 0) {
234 		fprintf(stderr, "bad block size %ld\n", fssize);
235 		done(1);
236 	}
237 	if (spcl.c_volume != 1) {
238 		fprintf(stderr, "Tape is not volume 1 of the dump\n");
239 		done(1);
240 	}
241 	if (gethead(&spcl) == FAIL) {
242 		dprintf(stdout, "header read failed at %ld blocks\n", blksread);
243 		panic("no header after volume mark!\n");
244 	}
245 	findinode(&spcl);
246 	if (spcl.c_type != TS_CLRI) {
247 		fprintf(stderr, "Cannot find file removal list\n");
248 		done(1);
249 	}
250 	maxino = (spcl.c_count * TP_BSIZE * NBBY) + 1;
251 	dprintf(stdout, "maxino = %d\n", maxino);
252 	map = calloc((unsigned)1, (unsigned)howmany(maxino, NBBY));
253 	if (map == NULL)
254 		panic("no memory for active inode map\n");
255 	usedinomap = map;
256 	curfile.action = USING;
257 	getfile(xtrmap, xtrmapskip);
258 	if (spcl.c_type != TS_BITS) {
259 		fprintf(stderr, "Cannot find file dump list\n");
260 		done(1);
261 	}
262 	map = calloc((unsigned)1, (unsigned)howmany(maxino, NBBY));
263 	if (map == (char *)NULL)
264 		panic("no memory for file dump list\n");
265 	dumpmap = map;
266 	curfile.action = USING;
267 	getfile(xtrmap, xtrmapskip);
268 	/*
269 	 * If there may be whiteout entries on the tape, pretend that the
270 	 * whiteout inode exists, so that the whiteout entries can be
271 	 * extracted.
272 	 */
273 	SETINO(WINO, dumpmap);
274 	/* 'r' restores don't call getvol() for tape 1, so mark it as read. */
275 	if (command == 'r')
276 		tapesread = 1;
277 }
278 
279 /*
280  * Prompt user to load a new dump volume.
281  * "Nextvol" is the next suggested volume to use.
282  * This suggested volume is enforced when doing full
283  * or incremental restores, but can be overridden by
284  * the user when only extracting a subset of the files.
285  */
286 void
287 getvol(long nextvol)
288 {
289 	int64_t prevtapea;
290 	long i, newvol, savecnt;
291 	union u_spcl tmpspcl;
292 #	define tmpbuf tmpspcl.s_spcl
293 	char buf[TP_BSIZE];
294 
295 	if (nextvol == 1) {
296 		tapesread = 0;
297 		gettingfile = 0;
298 	}
299 	prevtapea = tapeaddr;
300 	savecnt = blksread;
301 	if (pipein) {
302 		if (nextvol != 1) {
303 			panic("Changing volumes on pipe input?\n");
304 			/* Avoid looping if we couldn't ask the user. */
305 			if (yflag || ferror(terminal) || feof(terminal))
306 				done(1);
307 		}
308 		if (volno == 1)
309 			return;
310 		goto gethdr;
311 	}
312 again:
313 	if (pipein)
314 		done(1); /* pipes do not get a second chance */
315 	if (command == 'R' || command == 'r' || curfile.action != SKIP)
316 		newvol = nextvol;
317 	else
318 		newvol = 0;
319 	while (newvol <= 0) {
320 		if (tapesread == 0) {
321 			fprintf(stderr, "%s%s%s%s%s%s%s",
322 			    "You have not read any tapes yet.\n",
323 			    "If you are extracting just a few files,",
324 			    " start with the last volume\n",
325 			    "and work towards the first; restore",
326 			    " can quickly skip tapes that\n",
327 			    "have no further files to extract.",
328 			    " Otherwise, begin with volume 1.\n");
329 		} else {
330 			fprintf(stderr, "You have read volumes");
331 			strcpy(buf, ": ");
332 			for (i = 0; i < 32; i++)
333 				if (tapesread & (1 << i)) {
334 					fprintf(stderr, "%s%ld", buf, i + 1);
335 					strcpy(buf, ", ");
336 				}
337 			fprintf(stderr, "\n");
338 		}
339 		do	{
340 			fprintf(stderr, "Specify next volume #: ");
341 			(void) fflush(stderr);
342 			if (fgets(buf, BUFSIZ, terminal) == NULL)
343 				done(1);
344 		} while (buf[0] == '\n');
345 		newvol = atoi(buf);
346 		if (newvol <= 0) {
347 			fprintf(stderr,
348 			    "Volume numbers are positive numerics\n");
349 		}
350 	}
351 	if (newvol == volno) {
352 		tapesread |= 1 << (volno - 1);
353 		return;
354 	}
355 	closemt();
356 	fprintf(stderr, "Mount tape volume %ld\n", newvol);
357 	fprintf(stderr, "Enter ``none'' if there are no more tapes\n");
358 	fprintf(stderr, "otherwise enter tape name (default: %s) ", magtape);
359 	(void) fflush(stderr);
360 	if (fgets(buf, BUFSIZ, terminal) == NULL)
361 		done(1);
362 	if (!strcmp(buf, "none\n")) {
363 		terminateinput();
364 		return;
365 	}
366 	if (buf[0] != '\n') {
367 		(void) strcpy(magtape, buf);
368 		magtape[strlen(magtape) - 1] = '\0';
369 	}
370 #ifdef RRESTORE
371 	if (host)
372 		mt = rmtopen(magtape, 0);
373 	else
374 #endif
375 		mt = open(magtape, O_RDONLY, 0);
376 
377 	if (mt == -1) {
378 		fprintf(stderr, "Cannot open %s\n", magtape);
379 		volno = -1;
380 		goto again;
381 	}
382 gethdr:
383 	volno = newvol;
384 	setdumpnum();
385 	FLUSHTAPEBUF();
386 	if (gethead(&tmpbuf) == FAIL) {
387 		dprintf(stdout, "header read failed at %ld blocks\n", blksread);
388 		fprintf(stderr, "tape is not dump tape\n");
389 		volno = 0;
390 		goto again;
391 	}
392 	if (tmpbuf.c_volume != volno) {
393 		fprintf(stderr, "Wrong volume (%ld)\n", tmpbuf.c_volume);
394 		volno = 0;
395 		goto again;
396 	}
397 	if (_time64_to_time(tmpbuf.c_date) != dumpdate ||
398 	    _time64_to_time(tmpbuf.c_ddate) != dumptime) {
399 		time_t t = _time64_to_time(tmpbuf.c_date);
400 		fprintf(stderr, "Wrong dump date\n\tgot: %s", ctime(&t));
401 		fprintf(stderr, "\twanted: %s", ctime(&dumpdate));
402 		volno = 0;
403 		goto again;
404 	}
405 	tapesread |= 1 << (volno - 1);
406 	blksread = savecnt;
407  	/*
408  	 * If continuing from the previous volume, skip over any
409  	 * blocks read already at the end of the previous volume.
410  	 *
411  	 * If coming to this volume at random, skip to the beginning
412  	 * of the next record.
413  	 */
414 	dprintf(stdout, "last rec %qd, tape starts with %qd\n", prevtapea,
415 	    tmpbuf.c_tapea);
416  	if (tmpbuf.c_type == TS_TAPE) {
417  		if (curfile.action != USING) {
418 			/*
419 			 * XXX Dump incorrectly sets c_count to 1 in the
420 			 * volume header of the first tape, so ignore
421 			 * c_count when volno == 1.
422 			 */
423 			if (volno != 1)
424 				for (i = tmpbuf.c_count; i > 0; i--)
425 					readtape(buf);
426  		} else if (tmpbuf.c_tapea <= prevtapea) {
427 			/*
428 			 * Normally the value of c_tapea in the volume
429 			 * header is the record number of the header itself.
430 			 * However in the volume header following an EOT-
431 			 * terminated tape, it is the record number of the
432 			 * first continuation data block (dump bug?).
433 			 *
434 			 * The next record we want is `prevtapea + 1'.
435 			 */
436  			i = prevtapea + 1 - tmpbuf.c_tapea;
437 			dprintf(stderr, "Skipping %ld duplicate record%s.\n",
438 				i, i > 1 ? "s" : "");
439  			while (--i >= 0)
440  				readtape(buf);
441  		}
442  	}
443 	if (curfile.action == USING) {
444 		if (volno == 1)
445 			panic("active file into volume 1\n");
446 		return;
447 	}
448 	(void) gethead(&spcl);
449 	findinode(&spcl);
450 	if (gettingfile) {
451 		gettingfile = 0;
452 		longjmp(restart, 1);
453 	}
454 }
455 
456 /*
457  * Handle unexpected EOF.
458  */
459 static void
460 terminateinput(void)
461 {
462 
463 	if (gettingfile && curfile.action == USING) {
464 		printf("Warning: %s %s\n",
465 		    "End-of-input encountered while extracting", curfile.name);
466 	}
467 	curfile.name = "<name unknown>";
468 	curfile.action = UNKNOWN;
469 	curfile.mode = 0;
470 	curfile.ino = maxino;
471 	if (gettingfile) {
472 		gettingfile = 0;
473 		longjmp(restart, 1);
474 	}
475 }
476 
477 /*
478  * handle multiple dumps per tape by skipping forward to the
479  * appropriate one.
480  */
481 static void
482 setdumpnum(void)
483 {
484 	struct mtop tcom;
485 
486 	if (dumpnum == 1 || volno != 1)
487 		return;
488 	if (pipein) {
489 		fprintf(stderr, "Cannot have multiple dumps on pipe input\n");
490 		done(1);
491 	}
492 	tcom.mt_op = MTFSF;
493 	tcom.mt_count = dumpnum - 1;
494 #ifdef RRESTORE
495 	if (host)
496 		rmtioctl(MTFSF, dumpnum - 1);
497 	else
498 #endif
499 		if (ioctl(mt, MTIOCTOP, (char *)&tcom) < 0)
500 			fprintf(stderr, "ioctl MTFSF: %s\n", strerror(errno));
501 }
502 
503 void
504 printdumpinfo(void)
505 {
506 	time_t t;
507 	t = _time64_to_time(spcl.c_date);
508 	fprintf(stdout, "Dump   date: %s", ctime(&t));
509 	t = _time64_to_time(spcl.c_ddate);
510 	fprintf(stdout, "Dumped from: %s",
511 	    (spcl.c_ddate == 0) ? "the epoch\n" : ctime(&t));
512 	if (spcl.c_host[0] == '\0')
513 		return;
514 	fprintf(stderr, "Level %ld dump of %s on %s:%s\n",
515 		spcl.c_level, spcl.c_filesys, spcl.c_host, spcl.c_dev);
516 	fprintf(stderr, "Label: %s\n", spcl.c_label);
517 }
518 
519 int
520 extractfile(char *name)
521 {
522 	int flags;
523 	mode_t mode;
524 	struct timeval mtimep[2], ctimep[2];
525 	struct entry *ep;
526 
527 	curfile.name = name;
528 	curfile.action = USING;
529 	mtimep[0].tv_sec = curfile.atime_sec;
530 	mtimep[0].tv_usec = curfile.atime_nsec / 1000;
531 	mtimep[1].tv_sec = curfile.mtime_sec;
532 	mtimep[1].tv_usec = curfile.mtime_nsec / 1000;
533 	ctimep[0].tv_sec = curfile.atime_sec;
534 	ctimep[0].tv_usec = curfile.atime_nsec / 1000;
535 	ctimep[1].tv_sec = curfile.birthtime_sec;
536 	ctimep[1].tv_usec = curfile.birthtime_nsec / 1000;
537 	mode = curfile.mode;
538 	flags = curfile.file_flags;
539 	switch (mode & IFMT) {
540 
541 	default:
542 		fprintf(stderr, "%s: unknown file mode 0%o\n", name, mode);
543 		skipfile();
544 		return (FAIL);
545 
546 	case IFSOCK:
547 		vprintf(stdout, "skipped socket %s\n", name);
548 		skipfile();
549 		return (GOOD);
550 
551 	case IFDIR:
552 		if (mflag) {
553 			ep = lookupname(name);
554 			if (ep == NULL || ep->e_flags & EXTRACT)
555 				panic("unextracted directory %s\n", name);
556 			skipfile();
557 			return (GOOD);
558 		}
559 		vprintf(stdout, "extract file %s\n", name);
560 		return (genliteraldir(name, curfile.ino));
561 
562 	case IFLNK:
563 		lnkbuf[0] = '\0';
564 		pathlen = 0;
565 		getfile(xtrlnkfile, xtrlnkskip);
566 		if (pathlen == 0) {
567 			vprintf(stdout,
568 			    "%s: zero length symbolic link (ignored)\n", name);
569 			return (GOOD);
570 		}
571 		if (linkit(lnkbuf, name, SYMLINK) == GOOD) {
572 			(void) lchown(name, curfile.uid, curfile.gid);
573 			(void) lchmod(name, mode);
574 			(void) lutimes(name, ctimep);
575 			(void) lutimes(name, mtimep);
576 			return (GOOD);
577 		}
578 		return (FAIL);
579 
580 	case IFIFO:
581 		vprintf(stdout, "extract fifo %s\n", name);
582 		if (Nflag) {
583 			skipfile();
584 			return (GOOD);
585 		}
586 		if (uflag && !Nflag)
587 			(void)unlink(name);
588 		if (mkfifo(name, mode) < 0) {
589 			fprintf(stderr, "%s: cannot create fifo: %s\n",
590 			    name, strerror(errno));
591 			skipfile();
592 			return (FAIL);
593 		}
594 		(void) chown(name, curfile.uid, curfile.gid);
595 		(void) chmod(name, mode);
596 		(void) utimes(name, ctimep);
597 		(void) utimes(name, mtimep);
598 		(void) chflags(name, flags);
599 		skipfile();
600 		return (GOOD);
601 
602 	case IFCHR:
603 	case IFBLK:
604 		vprintf(stdout, "extract special file %s\n", name);
605 		if (Nflag) {
606 			skipfile();
607 			return (GOOD);
608 		}
609 		if (uflag)
610 			(void)unlink(name);
611 		if (mknod(name, mode, (int)curfile.rdev) < 0) {
612 			fprintf(stderr, "%s: cannot create special file: %s\n",
613 			    name, strerror(errno));
614 			skipfile();
615 			return (FAIL);
616 		}
617 		(void) chown(name, curfile.uid, curfile.gid);
618 		(void) chmod(name, mode);
619 		(void) utimes(name, ctimep);
620 		(void) utimes(name, mtimep);
621 		(void) chflags(name, flags);
622 		skipfile();
623 		return (GOOD);
624 
625 	case IFREG:
626 		vprintf(stdout, "extract file %s\n", name);
627 		if (Nflag) {
628 			skipfile();
629 			return (GOOD);
630 		}
631 		if (uflag)
632 			(void)unlink(name);
633 		if ((ofile = open(name, O_WRONLY | O_CREAT | O_TRUNC,
634 		    0666)) < 0) {
635 			fprintf(stderr, "%s: cannot create file: %s\n",
636 			    name, strerror(errno));
637 			skipfile();
638 			return (FAIL);
639 		}
640 		(void) fchown(ofile, curfile.uid, curfile.gid);
641 		(void) fchmod(ofile, mode);
642 		getfile(xtrfile, xtrskip);
643 		(void) close(ofile);
644 		(void) utimes(name, ctimep);
645 		(void) utimes(name, mtimep);
646 		(void) chflags(name, flags);
647 		return (GOOD);
648 	}
649 	/* NOTREACHED */
650 }
651 
652 /*
653  * skip over bit maps on the tape
654  */
655 void
656 skipmaps(void)
657 {
658 
659 	while (spcl.c_type == TS_BITS || spcl.c_type == TS_CLRI)
660 		skipfile();
661 }
662 
663 /*
664  * skip over a file on the tape
665  */
666 void
667 skipfile(void)
668 {
669 
670 	curfile.action = SKIP;
671 	getfile(xtrnull, xtrnull);
672 }
673 
674 /*
675  * Extract a file from the tape.
676  * When an allocated block is found it is passed to the fill function;
677  * when an unallocated block (hole) is found, a zeroed buffer is passed
678  * to the skip function.
679  */
680 void
681 getfile(void (*fill)(char *, long), void (*skip)(char *, long))
682 {
683 	int i;
684 	int curblk = 0;
685 	quad_t size = spcl.c_size;
686 	static char clearedbuf[MAXBSIZE];
687 	char buf[MAXBSIZE / TP_BSIZE][TP_BSIZE];
688 	char junk[TP_BSIZE];
689 
690 	if (spcl.c_type == TS_END)
691 		panic("ran off end of tape\n");
692 	if (spcl.c_magic != FS_UFS2_MAGIC)
693 		panic("not at beginning of a file\n");
694 	if (!gettingfile && setjmp(restart) != 0)
695 		return;
696 	gettingfile++;
697 loop:
698 	for (i = 0; i < spcl.c_count; i++) {
699 		if (readmapflag || spcl.c_addr[i]) {
700 			readtape(&buf[curblk++][0]);
701 			if (curblk == fssize / TP_BSIZE) {
702 				(*fill)((char *)buf, (long)(size > TP_BSIZE ?
703 				     fssize : (curblk - 1) * TP_BSIZE + size));
704 				curblk = 0;
705 			}
706 		} else {
707 			if (curblk > 0) {
708 				(*fill)((char *)buf, (long)(size > TP_BSIZE ?
709 				     curblk * TP_BSIZE :
710 				     (curblk - 1) * TP_BSIZE + size));
711 				curblk = 0;
712 			}
713 			(*skip)(clearedbuf, (long)(size > TP_BSIZE ?
714 				TP_BSIZE : size));
715 		}
716 		if ((size -= TP_BSIZE) <= 0) {
717 			for (i++; i < spcl.c_count; i++)
718 				if (readmapflag || spcl.c_addr[i])
719 					readtape(junk);
720 			break;
721 		}
722 	}
723 	if (gethead(&spcl) == GOOD && size > 0) {
724 		if (spcl.c_type == TS_ADDR)
725 			goto loop;
726 		dprintf(stdout,
727 			"Missing address (header) block for %s at %ld blocks\n",
728 			curfile.name, blksread);
729 	}
730 	if (curblk > 0)
731 		(*fill)((char *)buf, (long)((curblk * TP_BSIZE) + size));
732 	findinode(&spcl);
733 	gettingfile = 0;
734 }
735 
736 /*
737  * Write out the next block of a file.
738  */
739 static void
740 xtrfile(char *buf, long	size)
741 {
742 
743 	if (Nflag)
744 		return;
745 	if (write(ofile, buf, (int) size) == -1) {
746 		fprintf(stderr,
747 		    "write error extracting inode %d, name %s\nwrite: %s\n",
748 			curfile.ino, curfile.name, strerror(errno));
749 	}
750 }
751 
752 /*
753  * Skip over a hole in a file.
754  */
755 /* ARGSUSED */
756 static void
757 xtrskip(char *buf, long size)
758 {
759 
760 	if (lseek(ofile, size, SEEK_CUR) == -1) {
761 		fprintf(stderr,
762 		    "seek error extracting inode %d, name %s\nlseek: %s\n",
763 			curfile.ino, curfile.name, strerror(errno));
764 		done(1);
765 	}
766 }
767 
768 /*
769  * Collect the next block of a symbolic link.
770  */
771 static void
772 xtrlnkfile(char *buf, long size)
773 {
774 
775 	pathlen += size;
776 	if (pathlen > MAXPATHLEN) {
777 		fprintf(stderr, "symbolic link name: %s->%s%s; too long %d\n",
778 		    curfile.name, lnkbuf, buf, pathlen);
779 		done(1);
780 	}
781 	(void) strcat(lnkbuf, buf);
782 }
783 
784 /*
785  * Skip over a hole in a symbolic link (should never happen).
786  */
787 /* ARGSUSED */
788 static void
789 xtrlnkskip(char *buf, long size)
790 {
791 
792 	fprintf(stderr, "unallocated block in symbolic link %s\n",
793 		curfile.name);
794 	done(1);
795 }
796 
797 /*
798  * Collect the next block of a bit map.
799  */
800 static void
801 xtrmap(char *buf, long size)
802 {
803 
804 	memmove(map, buf, size);
805 	map += size;
806 }
807 
808 /*
809  * Skip over a hole in a bit map (should never happen).
810  */
811 /* ARGSUSED */
812 static void
813 xtrmapskip(char *buf, long size)
814 {
815 
816 	panic("hole in map\n");
817 	map += size;
818 }
819 
820 /*
821  * Noop, when an extraction function is not needed.
822  */
823 /* ARGSUSED */
824 void
825 xtrnull(char *buf, long size)
826 {
827 
828 	return;
829 }
830 
831 /*
832  * Read TP_BSIZE blocks from the input.
833  * Handle read errors, and end of media.
834  */
835 static void
836 readtape(char *buf)
837 {
838 	long rd, newvol, i;
839 	int cnt, seek_failed;
840 
841 	if (blkcnt < numtrec) {
842 		memmove(buf, &tapebuf[(blkcnt++ * TP_BSIZE)], (long)TP_BSIZE);
843 		blksread++;
844 		tapeaddr++;
845 		return;
846 	}
847 	for (i = 0; i < ntrec; i++)
848 		((struct s_spcl *)&tapebuf[i * TP_BSIZE])->c_magic = 0;
849 	if (numtrec == 0)
850 		numtrec = ntrec;
851 	cnt = ntrec * TP_BSIZE;
852 	rd = 0;
853 getmore:
854 #ifdef RRESTORE
855 	if (host)
856 		i = rmtread(&tapebuf[rd], cnt);
857 	else
858 #endif
859 		i = read(mt, &tapebuf[rd], cnt);
860 	/*
861 	 * Check for mid-tape short read error.
862 	 * If found, skip rest of buffer and start with the next.
863 	 */
864 	if (!pipein && numtrec < ntrec && i > 0) {
865 		dprintf(stdout, "mid-media short read error.\n");
866 		numtrec = ntrec;
867 	}
868 	/*
869 	 * Handle partial block read.
870 	 */
871 	if (pipein && i == 0 && rd > 0)
872 		i = rd;
873 	else if (i > 0 && i != ntrec * TP_BSIZE) {
874 		if (pipein) {
875 			rd += i;
876 			cnt -= i;
877 			if (cnt > 0)
878 				goto getmore;
879 			i = rd;
880 		} else {
881 			/*
882 			 * Short read. Process the blocks read.
883 			 */
884 			if (i % TP_BSIZE != 0)
885 				vprintf(stdout,
886 				    "partial block read: %ld should be %ld\n",
887 				    i, ntrec * TP_BSIZE);
888 			numtrec = i / TP_BSIZE;
889 		}
890 	}
891 	/*
892 	 * Handle read error.
893 	 */
894 	if (i < 0) {
895 		fprintf(stderr, "Tape read error while ");
896 		switch (curfile.action) {
897 		default:
898 			fprintf(stderr, "trying to set up tape\n");
899 			break;
900 		case UNKNOWN:
901 			fprintf(stderr, "trying to resynchronize\n");
902 			break;
903 		case USING:
904 			fprintf(stderr, "restoring %s\n", curfile.name);
905 			break;
906 		case SKIP:
907 			fprintf(stderr, "skipping over inode %d\n",
908 				curfile.ino);
909 			break;
910 		}
911 		if (!yflag && !reply("continue"))
912 			done(1);
913 		i = ntrec * TP_BSIZE;
914 		memset(tapebuf, 0, i);
915 #ifdef RRESTORE
916 		if (host)
917 			seek_failed = (rmtseek(i, 1) < 0);
918 		else
919 #endif
920 			seek_failed = (lseek(mt, i, SEEK_CUR) == (off_t)-1);
921 
922 		if (seek_failed) {
923 			fprintf(stderr,
924 			    "continuation failed: %s\n", strerror(errno));
925 			done(1);
926 		}
927 	}
928 	/*
929 	 * Handle end of tape.
930 	 */
931 	if (i == 0) {
932 		vprintf(stdout, "End-of-tape encountered\n");
933 		if (!pipein) {
934 			newvol = volno + 1;
935 			volno = 0;
936 			numtrec = 0;
937 			getvol(newvol);
938 			readtape(buf);
939 			return;
940 		}
941 		if (rd % TP_BSIZE != 0)
942 			panic("partial block read: %d should be %d\n",
943 				rd, ntrec * TP_BSIZE);
944 		terminateinput();
945 		memmove(&tapebuf[rd], &endoftapemark, (long)TP_BSIZE);
946 	}
947 	blkcnt = 0;
948 	memmove(buf, &tapebuf[(blkcnt++ * TP_BSIZE)], (long)TP_BSIZE);
949 	blksread++;
950 	tapeaddr++;
951 }
952 
953 static void
954 findtapeblksize(void)
955 {
956 	long i;
957 
958 	for (i = 0; i < ntrec; i++)
959 		((struct s_spcl *)&tapebuf[i * TP_BSIZE])->c_magic = 0;
960 	blkcnt = 0;
961 #ifdef RRESTORE
962 	if (host)
963 		i = rmtread(tapebuf, ntrec * TP_BSIZE);
964 	else
965 #endif
966 		i = read(mt, tapebuf, ntrec * TP_BSIZE);
967 
968 	if (i <= 0) {
969 		fprintf(stderr, "tape read error: %s\n", strerror(errno));
970 		done(1);
971 	}
972 	if (i % TP_BSIZE != 0) {
973 		fprintf(stderr, "Tape block size (%ld) %s (%d)\n",
974 			i, "is not a multiple of dump block size", TP_BSIZE);
975 		done(1);
976 	}
977 	ntrec = i / TP_BSIZE;
978 	numtrec = ntrec;
979 	vprintf(stdout, "Tape block size is %ld\n", ntrec);
980 }
981 
982 void
983 closemt(void)
984 {
985 
986 	if (mt < 0)
987 		return;
988 #ifdef RRESTORE
989 	if (host)
990 		rmtclose();
991 	else
992 #endif
993 		(void) close(mt);
994 }
995 
996 /*
997  * Read the next block from the tape.
998  * If it is not any valid header, return an error.
999  */
1000 static int
1001 gethead(struct s_spcl *buf)
1002 {
1003 	long i;
1004 
1005 	readtape((char *)buf);
1006 	if (buf->c_magic != FS_UFS2_MAGIC && buf->c_magic != NFS_MAGIC) {
1007 		if (buf->c_magic == OFS_MAGIC) {
1008 			fprintf(stderr,
1009 			    "Format of dump tape is too old. Must use\n");
1010 			fprintf(stderr,
1011 			    "a version of restore from before 2002.\n");
1012 			return (FAIL);
1013 		}
1014 		if (swabl(buf->c_magic) != FS_UFS2_MAGIC &&
1015 		    buf->c_magic != NFS_MAGIC) {
1016 			if (buf->c_magic == OFS_MAGIC) {
1017 				fprintf(stderr,
1018 				  "Format of dump tape is too old. Must use\n");
1019 				fprintf(stderr,
1020 				  "a version of restore from before 2002.\n");
1021 			}
1022 			return (FAIL);
1023 		}
1024 		if (!Bcvt) {
1025 			vprintf(stdout, "Note: Doing Byte swapping\n");
1026 			Bcvt = 1;
1027 		}
1028 	}
1029 	if (checksum((int *)buf) == FAIL)
1030 		return (FAIL);
1031 	if (Bcvt) {
1032 		swabst((u_char *)"8l4s1q8l2q17l", (u_char *)buf);
1033 		swabst((u_char *)"l",(u_char *) &buf->c_level);
1034 		swabst((u_char *)"2l4q",(u_char *) &buf->c_flags);
1035 	}
1036 	readmapflag = 0;
1037 
1038 	switch (buf->c_type) {
1039 
1040 	case TS_CLRI:
1041 	case TS_BITS:
1042 		/*
1043 		 * Have to patch up missing information in bit map headers
1044 		 */
1045 		buf->c_inumber = 0;
1046 		buf->c_size = buf->c_count * TP_BSIZE;
1047 		if (buf->c_count > TP_NINDIR)
1048 			readmapflag = 1;
1049 		else
1050 			for (i = 0; i < buf->c_count; i++)
1051 				buf->c_addr[i]++;
1052 		break;
1053 
1054 	case TS_TAPE:
1055 	case TS_END:
1056 		buf->c_inumber = 0;
1057 		break;
1058 
1059 	case TS_INODE:
1060 		/*
1061 		 * For old dump tapes, have to copy up old fields to
1062 		 * new locations.
1063 		 */
1064 		if (buf->c_magic == NFS_MAGIC) {
1065 			buf->c_tapea = buf->c_old_tapea;
1066 			buf->c_firstrec = buf->c_old_firstrec;
1067 			buf->c_date = _time32_to_time(buf->c_old_date);
1068 			buf->c_ddate = _time32_to_time(buf->c_old_ddate);
1069 			buf->c_atime = _time32_to_time(buf->c_old_atime);
1070 			buf->c_mtime = _time32_to_time(buf->c_old_mtime);
1071 		}
1072 		break;
1073 
1074 	case TS_ADDR:
1075 		break;
1076 
1077 	default:
1078 		panic("gethead: unknown inode type %d\n", buf->c_type);
1079 		break;
1080 	}
1081 	buf->c_magic = FS_UFS2_MAGIC;
1082 	tapeaddr = buf->c_tapea;
1083 	if (dflag)
1084 		accthdr(buf);
1085 	return(GOOD);
1086 }
1087 
1088 /*
1089  * Check that a header is where it belongs and predict the next header
1090  */
1091 static void
1092 accthdr(struct s_spcl *header)
1093 {
1094 	static ino_t previno = 0x7fffffff;
1095 	static int prevtype;
1096 	static long predict;
1097 	long blks, i;
1098 
1099 	if (header->c_type == TS_TAPE) {
1100 		fprintf(stderr, "Volume header ");
1101  		if (header->c_firstrec)
1102  			fprintf(stderr, "begins with record %qd",
1103  				header->c_firstrec);
1104  		fprintf(stderr, "\n");
1105 		previno = 0x7fffffff;
1106 		return;
1107 	}
1108 	if (previno == 0x7fffffff)
1109 		goto newcalc;
1110 	switch (prevtype) {
1111 	case TS_BITS:
1112 		fprintf(stderr, "Dumped inodes map header");
1113 		break;
1114 	case TS_CLRI:
1115 		fprintf(stderr, "Used inodes map header");
1116 		break;
1117 	case TS_INODE:
1118 		fprintf(stderr, "File header, ino %d", previno);
1119 		break;
1120 	case TS_ADDR:
1121 		fprintf(stderr, "File continuation header, ino %d", previno);
1122 		break;
1123 	case TS_END:
1124 		fprintf(stderr, "End of tape header");
1125 		break;
1126 	}
1127 	if (predict != blksread - 1)
1128 		fprintf(stderr, "; predicted %ld blocks, got %ld blocks",
1129 			predict, blksread - 1);
1130 	fprintf(stderr, "\n");
1131 newcalc:
1132 	blks = 0;
1133 	if (header->c_type != TS_END)
1134 		for (i = 0; i < header->c_count; i++)
1135 			if (readmapflag || header->c_addr[i] != 0)
1136 				blks++;
1137 	predict = blks;
1138 	blksread = 0;
1139 	prevtype = header->c_type;
1140 	previno = header->c_inumber;
1141 }
1142 
1143 /*
1144  * Find an inode header.
1145  * Complain if had to skip.
1146  */
1147 static void
1148 findinode(struct s_spcl *header)
1149 {
1150 	static long skipcnt = 0;
1151 	long i;
1152 	char buf[TP_BSIZE];
1153 	int htype;
1154 
1155 	curfile.name = "<name unknown>";
1156 	curfile.action = UNKNOWN;
1157 	curfile.mode = 0;
1158 	curfile.ino = 0;
1159 	do {
1160 		htype = header->c_type;
1161 		switch (htype) {
1162 
1163 		case TS_ADDR:
1164 			/*
1165 			 * Skip up to the beginning of the next record
1166 			 */
1167 			for (i = 0; i < header->c_count; i++)
1168 				if (header->c_addr[i])
1169 					readtape(buf);
1170 			while (gethead(header) == FAIL ||
1171 			    _time64_to_time(header->c_date) != dumpdate)
1172 				skipcnt++;
1173 			break;
1174 
1175 		case TS_INODE:
1176 			curfile.mode = header->c_mode;
1177 			curfile.uid = header->c_uid;
1178 			curfile.gid = header->c_gid;
1179 			curfile.file_flags = header->c_file_flags;
1180 			curfile.rdev = header->c_rdev;
1181 			curfile.atime_sec = header->c_atime;
1182 			curfile.atime_nsec = header->c_atimensec;
1183 			curfile.mtime_sec = header->c_mtime;
1184 			curfile.mtime_nsec = header->c_mtimensec;
1185 			curfile.birthtime_sec = header->c_birthtime;
1186 			curfile.birthtime_nsec = header->c_birthtimensec;
1187 			curfile.size = header->c_size;
1188 			curfile.ino = header->c_inumber;
1189 			break;
1190 
1191 		case TS_END:
1192 			/* If we missed some tapes, get another volume. */
1193 			if (tapesread & (tapesread + 1)) {
1194 				getvol(0);
1195 				continue;
1196 			}
1197 			curfile.ino = maxino;
1198 			break;
1199 
1200 		case TS_CLRI:
1201 			curfile.name = "<file removal list>";
1202 			break;
1203 
1204 		case TS_BITS:
1205 			curfile.name = "<file dump list>";
1206 			break;
1207 
1208 		case TS_TAPE:
1209 			panic("unexpected tape header\n");
1210 			/* NOTREACHED */
1211 
1212 		default:
1213 			panic("unknown tape header type %d\n", spcl.c_type);
1214 			/* NOTREACHED */
1215 
1216 		}
1217 	} while (htype == TS_ADDR);
1218 	if (skipcnt > 0)
1219 		fprintf(stderr, "resync restore, skipped %ld blocks\n",
1220 		    skipcnt);
1221 	skipcnt = 0;
1222 }
1223 
1224 static int
1225 checksum(int *buf)
1226 {
1227 	int i, j;
1228 
1229 	j = sizeof(union u_spcl) / sizeof(int);
1230 	i = 0;
1231 	if (!Bcvt) {
1232 		do
1233 			i += *buf++;
1234 		while (--j);
1235 	} else {
1236 		/* What happens if we want to read restore tapes
1237 			for a 16bit int machine??? */
1238 		do
1239 			i += swabl(*buf++);
1240 		while (--j);
1241 	}
1242 
1243 	if (i != CHECKSUM) {
1244 		fprintf(stderr, "Checksum error %o, inode %d file %s\n", i,
1245 			curfile.ino, curfile.name);
1246 		return(FAIL);
1247 	}
1248 	return(GOOD);
1249 }
1250 
1251 #ifdef RRESTORE
1252 #include <stdarg.h>
1253 
1254 void
1255 msg(const char *fmt, ...)
1256 {
1257 	va_list ap;
1258 	va_start(ap, fmt);
1259 	(void)vfprintf(stderr, fmt, ap);
1260 	va_end(ap);
1261 }
1262 #endif /* RRESTORE */
1263 
1264 static u_char *
1265 swabshort(u_char *sp, int n)
1266 {
1267 	char c;
1268 
1269 	while (--n >= 0) {
1270 		c = sp[0]; sp[0] = sp[1]; sp[1] = c;
1271 		sp += 2;
1272 	}
1273 	return (sp);
1274 }
1275 
1276 static u_char *
1277 swablong(u_char *sp, int n)
1278 {
1279 	char c;
1280 
1281 	while (--n >= 0) {
1282 		c = sp[0]; sp[0] = sp[3]; sp[3] = c;
1283 		c = sp[2]; sp[2] = sp[1]; sp[1] = c;
1284 		sp += 4;
1285 	}
1286 	return (sp);
1287 }
1288 
1289 static u_char *
1290 swabquad(u_char *sp, int n)
1291 {
1292 	char c;
1293 
1294 	while (--n >= 0) {
1295 		c = sp[0]; sp[0] = sp[7]; sp[7] = c;
1296 		c = sp[1]; sp[1] = sp[6]; sp[6] = c;
1297 		c = sp[2]; sp[2] = sp[5]; sp[5] = c;
1298 		c = sp[3]; sp[3] = sp[4]; sp[4] = c;
1299 		sp += 8;
1300 	}
1301 	return (sp);
1302 }
1303 
1304 void
1305 swabst(u_char *cp, u_char *sp)
1306 {
1307 	int n = 0;
1308 
1309 	while (*cp) {
1310 		switch (*cp) {
1311 		case '0': case '1': case '2': case '3': case '4':
1312 		case '5': case '6': case '7': case '8': case '9':
1313 			n = (n * 10) + (*cp++ - '0');
1314 			continue;
1315 
1316 		case 's': case 'w': case 'h':
1317 			if (n == 0)
1318 				n = 1;
1319 			sp = swabshort(sp, n);
1320 			break;
1321 
1322 		case 'l':
1323 			if (n == 0)
1324 				n = 1;
1325 			sp = swablong(sp, n);
1326 			break;
1327 
1328 		case 'q':
1329 			if (n == 0)
1330 				n = 1;
1331 			sp = swabquad(sp, n);
1332 			break;
1333 
1334 		case 'b':
1335 			if (n == 0)
1336 				n = 1;
1337 			sp += n;
1338 			break;
1339 
1340 		default:
1341 			fprintf(stderr, "Unknown conversion character: %c\n",
1342 			    *cp);
1343 			done(0);
1344 			break;
1345 		}
1346 		cp++;
1347 		n = 0;
1348 	}
1349 }
1350 
1351 static u_long
1352 swabl(u_long x)
1353 {
1354 	swabst((u_char *)"l", (u_char *)&x);
1355 	return (x);
1356 }
1357