xref: /freebsd/sbin/restore/tape.c (revision c11e094d96120a2e0e726ed9705ae0ec08db49b6)
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 long	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 
83 static int	ofile;
84 static char	*map;
85 static char	lnkbuf[MAXPATHLEN + 1];
86 static int	pathlen;
87 
88 int		oldinofmt;	/* old inode format conversion required */
89 int		Bcvt;		/* Swap Bytes (for CCI or sun) */
90 static int	Qcvt;		/* Swap quads (for sun) */
91 
92 #define	FLUSHTAPEBUF()	blkcnt = ntrec + 1
93 
94 static void	 accthdr(struct s_spcl *);
95 static int	 checksum(int *);
96 static void	 findinode(struct s_spcl *);
97 static void	 findtapeblksize(void);
98 static int	 gethead(struct s_spcl *);
99 static void	 readtape(char *);
100 static void	 setdumpnum(void);
101 static u_long	 swabl(u_long);
102 static u_char	*swablong(u_char *, int);
103 static u_char	*swabshort(u_char *, int);
104 static void	 terminateinput(void);
105 static void	 xtrfile(char *, long);
106 static void	 xtrlnkfile(char *, long);
107 static void	 xtrlnkskip(char *, long);
108 static void	 xtrmap(char *, long);
109 static void	 xtrmapskip(char *, long);
110 static void	 xtrskip(char *, long);
111 
112 static int readmapflag;
113 
114 /*
115  * Set up an input source
116  */
117 void
118 setinput(char *source)
119 {
120 	FLUSHTAPEBUF();
121 	if (bflag)
122 		newtapebuf(ntrec);
123 	else
124 		newtapebuf(NTREC > HIGHDENSITYTREC ? NTREC : HIGHDENSITYTREC);
125 	terminal = stdin;
126 
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 #ifdef RRESTORE
192 	if (host)
193 		mt = rmtopen(magtape, 0);
194 	else
195 #endif
196 	if (pipein)
197 		mt = 0;
198 	else
199 		mt = open(magtape, O_RDONLY, 0);
200 	if (mt < 0) {
201 		fprintf(stderr, "%s: %s\n", magtape, strerror(errno));
202 		done(1);
203 	}
204 	volno = 1;
205 	setdumpnum();
206 	FLUSHTAPEBUF();
207 	if (!pipein && !bflag)
208 		findtapeblksize();
209 	if (gethead(&spcl) == FAIL) {
210 		blkcnt--; /* push back this block */
211 		blksread--;
212 		cvtflag++;
213 		if (gethead(&spcl) == FAIL) {
214 			fprintf(stderr, "Tape is not a dump tape\n");
215 			done(1);
216 		}
217 		fprintf(stderr, "Converting to new filesystem format.\n");
218 	}
219 	if (pipein) {
220 		endoftapemark.s_spcl.c_magic = cvtflag ? OFS_MAGIC : NFS_MAGIC;
221 		endoftapemark.s_spcl.c_type = TS_END;
222 		ip = (int *)&endoftapemark;
223 		j = sizeof(union u_spcl) / sizeof(int);
224 		i = 0;
225 		do
226 			i += *ip++;
227 		while (--j);
228 		endoftapemark.s_spcl.c_checksum = CHECKSUM - i;
229 	}
230 	if (vflag || command == 't')
231 		printdumpinfo();
232 	dumptime = _time32_to_time(spcl.c_ddate);
233 	dumpdate = _time32_to_time(spcl.c_date);
234 	if (stat(".", &stbuf) < 0) {
235 		fprintf(stderr, "cannot stat .: %s\n", strerror(errno));
236 		done(1);
237 	}
238 	if (stbuf.st_blksize > 0 && stbuf.st_blksize < TP_BSIZE )
239 		fssize = TP_BSIZE;
240 	if (stbuf.st_blksize >= TP_BSIZE && stbuf.st_blksize <= MAXBSIZE)
241 		fssize = stbuf.st_blksize;
242 	if (((fssize - 1) & fssize) != 0) {
243 		fprintf(stderr, "bad block size %ld\n", fssize);
244 		done(1);
245 	}
246 	if (spcl.c_volume != 1) {
247 		fprintf(stderr, "Tape is not volume 1 of the dump\n");
248 		done(1);
249 	}
250 	if (gethead(&spcl) == FAIL) {
251 		dprintf(stdout, "header read failed at %ld blocks\n", blksread);
252 		panic("no header after volume mark!\n");
253 	}
254 	findinode(&spcl);
255 	if (spcl.c_type != TS_CLRI) {
256 		fprintf(stderr, "Cannot find file removal list\n");
257 		done(1);
258 	}
259 	maxino = (spcl.c_count * TP_BSIZE * NBBY) + 1;
260 	dprintf(stdout, "maxino = %d\n", maxino);
261 	map = calloc((unsigned)1, (unsigned)howmany(maxino, NBBY));
262 	if (map == NULL)
263 		panic("no memory for active inode map\n");
264 	usedinomap = map;
265 	curfile.action = USING;
266 	getfile(xtrmap, xtrmapskip);
267 	if (spcl.c_type != TS_BITS) {
268 		fprintf(stderr, "Cannot find file dump list\n");
269 		done(1);
270 	}
271 	map = calloc((unsigned)1, (unsigned)howmany(maxino, NBBY));
272 	if (map == (char *)NULL)
273 		panic("no memory for file dump list\n");
274 	dumpmap = map;
275 	curfile.action = USING;
276 	getfile(xtrmap, xtrmapskip);
277 	/*
278 	 * If there may be whiteout entries on the tape, pretend that the
279 	 * whiteout inode exists, so that the whiteout entries can be
280 	 * extracted.
281 	 */
282 	if (oldinofmt == 0)
283 		SETINO(WINO, dumpmap);
284 	/* 'r' restores don't call getvol() for tape 1, so mark it as read. */
285 	if (command == 'r')
286 		tapesread = 1;
287 }
288 
289 /*
290  * Prompt user to load a new dump volume.
291  * "Nextvol" is the next suggested volume to use.
292  * This suggested volume is enforced when doing full
293  * or incremental restores, but can be overridden by
294  * the user when only extracting a subset of the files.
295  */
296 void
297 getvol(long nextvol)
298 {
299 	long newvol, prevtapea, savecnt, i;
300 	union u_spcl tmpspcl;
301 #	define tmpbuf tmpspcl.s_spcl
302 	char buf[TP_BSIZE];
303 
304 	if (nextvol == 1) {
305 		tapesread = 0;
306 		gettingfile = 0;
307 	}
308 	prevtapea = tapeaddr;
309 	savecnt = blksread;
310 	if (pipein) {
311 		if (nextvol != 1) {
312 			panic("Changing volumes on pipe input?\n");
313 			/* Avoid looping if we couldn't ask the user. */
314 			if (yflag || ferror(terminal) || feof(terminal))
315 				done(1);
316 		}
317 		if (volno == 1)
318 			return;
319 		goto gethdr;
320 	}
321 again:
322 	if (pipein)
323 		done(1); /* pipes do not get a second chance */
324 	if (command == 'R' || command == 'r' || curfile.action != SKIP)
325 		newvol = nextvol;
326 	else
327 		newvol = 0;
328 	while (newvol <= 0) {
329 		if (tapesread == 0) {
330 			fprintf(stderr, "%s%s%s%s%s%s%s",
331 			    "You have not read any tapes yet.\n",
332 			    "If you are extracting just a few files,",
333 			    " start with the last volume\n",
334 			    "and work towards the first; restore",
335 			    " can quickly skip tapes that\n",
336 			    "have no further files to extract.",
337 			    " Otherwise, begin with volume 1.\n");
338 		} else {
339 			fprintf(stderr, "You have read volumes");
340 			strcpy(buf, ": ");
341 			for (i = 0; i < 32; i++)
342 				if (tapesread & (1 << i)) {
343 					fprintf(stderr, "%s%ld", buf, i + 1);
344 					strcpy(buf, ", ");
345 				}
346 			fprintf(stderr, "\n");
347 		}
348 		do	{
349 			fprintf(stderr, "Specify next volume #: ");
350 			(void) fflush(stderr);
351 			if (fgets(buf, BUFSIZ, terminal) == NULL)
352 				done(1);
353 		} while (buf[0] == '\n');
354 		newvol = atoi(buf);
355 		if (newvol <= 0) {
356 			fprintf(stderr,
357 			    "Volume numbers are positive numerics\n");
358 		}
359 	}
360 	if (newvol == volno) {
361 		tapesread |= 1 << (volno - 1);
362 		return;
363 	}
364 	closemt();
365 	fprintf(stderr, "Mount tape volume %ld\n", newvol);
366 	fprintf(stderr, "Enter ``none'' if there are no more tapes\n");
367 	fprintf(stderr, "otherwise enter tape name (default: %s) ", magtape);
368 	(void) fflush(stderr);
369 	if (fgets(buf, BUFSIZ, terminal) == NULL)
370 		done(1);
371 	if (!strcmp(buf, "none\n")) {
372 		terminateinput();
373 		return;
374 	}
375 	if (buf[0] != '\n') {
376 		(void) strcpy(magtape, buf);
377 		magtape[strlen(magtape) - 1] = '\0';
378 	}
379 #ifdef RRESTORE
380 	if (host)
381 		mt = rmtopen(magtape, 0);
382 	else
383 #endif
384 		mt = open(magtape, O_RDONLY, 0);
385 
386 	if (mt == -1) {
387 		fprintf(stderr, "Cannot open %s\n", magtape);
388 		volno = -1;
389 		goto again;
390 	}
391 gethdr:
392 	volno = newvol;
393 	setdumpnum();
394 	FLUSHTAPEBUF();
395 	if (gethead(&tmpbuf) == FAIL) {
396 		dprintf(stdout, "header read failed at %ld blocks\n", blksread);
397 		fprintf(stderr, "tape is not dump tape\n");
398 		volno = 0;
399 		goto again;
400 	}
401 	if (tmpbuf.c_volume != volno) {
402 		fprintf(stderr, "Wrong volume (%ld)\n", tmpbuf.c_volume);
403 		volno = 0;
404 		goto again;
405 	}
406 	if (_time32_to_time(tmpbuf.c_date) != dumpdate ||
407 	    _time32_to_time(tmpbuf.c_ddate) != dumptime) {
408 		time_t t = _time32_to_time(tmpbuf.c_date);
409 		fprintf(stderr, "Wrong dump date\n\tgot: %s", ctime(&t));
410 		fprintf(stderr, "\twanted: %s", ctime(&dumpdate));
411 		volno = 0;
412 		goto again;
413 	}
414 	tapesread |= 1 << (volno - 1);
415 	blksread = savecnt;
416  	/*
417  	 * If continuing from the previous volume, skip over any
418  	 * blocks read already at the end of the previous volume.
419  	 *
420  	 * If coming to this volume at random, skip to the beginning
421  	 * of the next record.
422  	 */
423 	dprintf(stdout, "last rec %ld, tape starts with %ld\n", prevtapea,
424 	    tmpbuf.c_tapea);
425  	if (tmpbuf.c_type == TS_TAPE && (tmpbuf.c_flags & DR_NEWHEADER)) {
426  		if (curfile.action != USING) {
427 			/*
428 			 * XXX Dump incorrectly sets c_count to 1 in the
429 			 * volume header of the first tape, so ignore
430 			 * c_count when volno == 1.
431 			 */
432 			if (volno != 1)
433 				for (i = tmpbuf.c_count; i > 0; i--)
434 					readtape(buf);
435  		} else if (tmpbuf.c_tapea <= prevtapea) {
436 			/*
437 			 * Normally the value of c_tapea in the volume
438 			 * header is the record number of the header itself.
439 			 * However in the volume header following an EOT-
440 			 * terminated tape, it is the record number of the
441 			 * first continuation data block (dump bug?).
442 			 *
443 			 * The next record we want is `prevtapea + 1'.
444 			 */
445  			i = prevtapea + 1 - tmpbuf.c_tapea;
446 			dprintf(stderr, "Skipping %ld duplicate record%s.\n",
447 				i, i > 1 ? "s" : "");
448  			while (--i >= 0)
449  				readtape(buf);
450  		}
451  	}
452 	if (curfile.action == USING) {
453 		if (volno == 1)
454 			panic("active file into volume 1\n");
455 		return;
456 	}
457 	(void) gethead(&spcl);
458 	findinode(&spcl);
459 	if (gettingfile) {
460 		gettingfile = 0;
461 		longjmp(restart, 1);
462 	}
463 }
464 
465 /*
466  * Handle unexpected EOF.
467  */
468 static void
469 terminateinput(void)
470 {
471 
472 	if (gettingfile && curfile.action == USING) {
473 		printf("Warning: %s %s\n",
474 		    "End-of-input encountered while extracting", curfile.name);
475 	}
476 	curfile.name = "<name unknown>";
477 	curfile.action = UNKNOWN;
478 	curfile.dip = NULL;
479 	curfile.ino = maxino;
480 	if (gettingfile) {
481 		gettingfile = 0;
482 		longjmp(restart, 1);
483 	}
484 }
485 
486 /*
487  * handle multiple dumps per tape by skipping forward to the
488  * appropriate one.
489  */
490 static void
491 setdumpnum(void)
492 {
493 	struct mtop tcom;
494 
495 	if (dumpnum == 1 || volno != 1)
496 		return;
497 	if (pipein) {
498 		fprintf(stderr, "Cannot have multiple dumps on pipe input\n");
499 		done(1);
500 	}
501 	tcom.mt_op = MTFSF;
502 	tcom.mt_count = dumpnum - 1;
503 #ifdef RRESTORE
504 	if (host)
505 		rmtioctl(MTFSF, dumpnum - 1);
506 	else
507 #endif
508 		if (ioctl(mt, MTIOCTOP, (char *)&tcom) < 0)
509 			fprintf(stderr, "ioctl MTFSF: %s\n", strerror(errno));
510 }
511 
512 void
513 printdumpinfo(void)
514 {
515 	time_t t;
516 	t = _time32_to_time(spcl.c_date);
517 	fprintf(stdout, "Dump   date: %s", ctime(&t));
518 	t = _time32_to_time(spcl.c_ddate);
519 	fprintf(stdout, "Dumped from: %s",
520 	    (spcl.c_ddate == 0) ? "the epoch\n" : ctime(&t));
521 	if (spcl.c_host[0] == '\0')
522 		return;
523 	fprintf(stderr, "Level %ld dump of %s on %s:%s\n",
524 		spcl.c_level, spcl.c_filesys, spcl.c_host, spcl.c_dev);
525 	fprintf(stderr, "Label: %s\n", spcl.c_label);
526 }
527 
528 int
529 extractfile(char *name)
530 {
531 	int flags;
532 	uid_t uid;
533 	gid_t gid;
534 	mode_t mode;
535 	struct timeval timep[2];
536 	struct entry *ep;
537 
538 	curfile.name = name;
539 	curfile.action = USING;
540 	timep[0].tv_sec = curfile.dip->di_atime;
541 	timep[0].tv_usec = curfile.dip->di_atimensec / 1000;
542 	timep[1].tv_sec = curfile.dip->di_mtime;
543 	timep[1].tv_usec = curfile.dip->di_mtimensec / 1000;
544 	uid = curfile.dip->di_uid;
545 	gid = curfile.dip->di_gid;
546 	mode = curfile.dip->di_mode;
547 	flags = curfile.dip->di_flags;
548 	switch (mode & IFMT) {
549 
550 	default:
551 		fprintf(stderr, "%s: unknown file mode 0%o\n", name, mode);
552 		skipfile();
553 		return (FAIL);
554 
555 	case IFSOCK:
556 		vprintf(stdout, "skipped socket %s\n", name);
557 		skipfile();
558 		return (GOOD);
559 
560 	case IFDIR:
561 		if (mflag) {
562 			ep = lookupname(name);
563 			if (ep == NULL || ep->e_flags & EXTRACT)
564 				panic("unextracted directory %s\n", name);
565 			skipfile();
566 			return (GOOD);
567 		}
568 		vprintf(stdout, "extract file %s\n", name);
569 		return (genliteraldir(name, curfile.ino));
570 
571 	case IFLNK:
572 		lnkbuf[0] = '\0';
573 		pathlen = 0;
574 		getfile(xtrlnkfile, xtrlnkskip);
575 		if (pathlen == 0) {
576 			vprintf(stdout,
577 			    "%s: zero length symbolic link (ignored)\n", name);
578 			return (GOOD);
579 		}
580 		if (linkit(lnkbuf, name, SYMLINK) == GOOD) {
581 			(void) lchown(name, uid, gid);
582 			(void) lchmod(name, mode);
583 			(void) lutimes(name, timep);
584 			return (GOOD);
585 		}
586 		return (FAIL);
587 
588 	case IFIFO:
589 		vprintf(stdout, "extract fifo %s\n", name);
590 		if (Nflag) {
591 			skipfile();
592 			return (GOOD);
593 		}
594 		if (uflag && !Nflag)
595 			(void)unlink(name);
596 		if (mkfifo(name, mode) < 0) {
597 			fprintf(stderr, "%s: cannot create fifo: %s\n",
598 			    name, strerror(errno));
599 			skipfile();
600 			return (FAIL);
601 		}
602 		(void) chown(name, uid, gid);
603 		(void) chmod(name, mode);
604 		(void) utimes(name, timep);
605 		(void) chflags(name, flags);
606 		skipfile();
607 		return (GOOD);
608 
609 	case IFCHR:
610 	case IFBLK:
611 		vprintf(stdout, "extract special file %s\n", name);
612 		if (Nflag) {
613 			skipfile();
614 			return (GOOD);
615 		}
616 		if (uflag)
617 			(void)unlink(name);
618 		if (mknod(name, mode, (int)curfile.dip->di_rdev) < 0) {
619 			fprintf(stderr, "%s: cannot create special file: %s\n",
620 			    name, strerror(errno));
621 			skipfile();
622 			return (FAIL);
623 		}
624 		(void) chown(name, uid, gid);
625 		(void) chmod(name, mode);
626 		(void) utimes(name, timep);
627 		(void) chflags(name, flags);
628 		skipfile();
629 		return (GOOD);
630 
631 	case IFREG:
632 		vprintf(stdout, "extract file %s\n", name);
633 		if (Nflag) {
634 			skipfile();
635 			return (GOOD);
636 		}
637 		if (uflag)
638 			(void)unlink(name);
639 		if ((ofile = open(name, O_WRONLY | O_CREAT | O_TRUNC,
640 		    0666)) < 0) {
641 			fprintf(stderr, "%s: cannot create file: %s\n",
642 			    name, strerror(errno));
643 			skipfile();
644 			return (FAIL);
645 		}
646 		(void) fchown(ofile, uid, gid);
647 		(void) fchmod(ofile, mode);
648 		getfile(xtrfile, xtrskip);
649 		(void) close(ofile);
650 		utimes(name, timep);
651 		(void) chflags(name, flags);
652 		return (GOOD);
653 	}
654 	/* NOTREACHED */
655 }
656 
657 /*
658  * skip over bit maps on the tape
659  */
660 void
661 skipmaps(void)
662 {
663 
664 	while (spcl.c_type == TS_BITS || spcl.c_type == TS_CLRI)
665 		skipfile();
666 }
667 
668 /*
669  * skip over a file on the tape
670  */
671 void
672 skipfile(void)
673 {
674 
675 	curfile.action = SKIP;
676 	getfile(xtrnull, xtrnull);
677 }
678 
679 /*
680  * Extract a file from the tape.
681  * When an allocated block is found it is passed to the fill function;
682  * when an unallocated block (hole) is found, a zeroed buffer is passed
683  * to the skip function.
684  */
685 void
686 getfile(void (*fill)(char *, long), void (*skip)(char *, long))
687 {
688 	int i;
689 	int curblk = 0;
690 	quad_t size = spcl.c_dinode.di_size;
691 	static char clearedbuf[MAXBSIZE];
692 	char buf[MAXBSIZE / TP_BSIZE][TP_BSIZE];
693 	char junk[TP_BSIZE];
694 
695 	if (spcl.c_type == TS_END)
696 		panic("ran off end of tape\n");
697 	if (spcl.c_magic != NFS_MAGIC)
698 		panic("not at beginning of a file\n");
699 	if (!gettingfile && setjmp(restart) != 0)
700 		return;
701 	gettingfile++;
702 loop:
703 	for (i = 0; i < spcl.c_count; i++) {
704 		if (readmapflag || spcl.c_addr[i]) {
705 			readtape(&buf[curblk++][0]);
706 			if (curblk == fssize / TP_BSIZE) {
707 				(*fill)((char *)buf, (long)(size > TP_BSIZE ?
708 				     fssize : (curblk - 1) * TP_BSIZE + size));
709 				curblk = 0;
710 			}
711 		} else {
712 			if (curblk > 0) {
713 				(*fill)((char *)buf, (long)(size > TP_BSIZE ?
714 				     curblk * TP_BSIZE :
715 				     (curblk - 1) * TP_BSIZE + size));
716 				curblk = 0;
717 			}
718 			(*skip)(clearedbuf, (long)(size > TP_BSIZE ?
719 				TP_BSIZE : size));
720 		}
721 		if ((size -= TP_BSIZE) <= 0) {
722 			for (i++; i < spcl.c_count; i++)
723 				if (readmapflag || spcl.c_addr[i])
724 					readtape(junk);
725 			break;
726 		}
727 	}
728 	if (gethead(&spcl) == GOOD && size > 0) {
729 		if (spcl.c_type == TS_ADDR)
730 			goto loop;
731 		dprintf(stdout,
732 			"Missing address (header) block for %s at %ld blocks\n",
733 			curfile.name, blksread);
734 	}
735 	if (curblk > 0)
736 		(*fill)((char *)buf, (long)((curblk * TP_BSIZE) + size));
737 	findinode(&spcl);
738 	gettingfile = 0;
739 }
740 
741 /*
742  * Write out the next block of a file.
743  */
744 static void
745 xtrfile(char *buf, long	size)
746 {
747 
748 	if (Nflag)
749 		return;
750 	if (write(ofile, buf, (int) size) == -1) {
751 		fprintf(stderr,
752 		    "write error extracting inode %d, name %s\nwrite: %s\n",
753 			curfile.ino, curfile.name, strerror(errno));
754 	}
755 }
756 
757 /*
758  * Skip over a hole in a file.
759  */
760 /* ARGSUSED */
761 static void
762 xtrskip(char *buf, long size)
763 {
764 
765 	if (lseek(ofile, size, SEEK_CUR) == -1) {
766 		fprintf(stderr,
767 		    "seek error extracting inode %d, name %s\nlseek: %s\n",
768 			curfile.ino, curfile.name, strerror(errno));
769 		done(1);
770 	}
771 }
772 
773 /*
774  * Collect the next block of a symbolic link.
775  */
776 static void
777 xtrlnkfile(char *buf, long size)
778 {
779 
780 	pathlen += size;
781 	if (pathlen > MAXPATHLEN) {
782 		fprintf(stderr, "symbolic link name: %s->%s%s; too long %d\n",
783 		    curfile.name, lnkbuf, buf, pathlen);
784 		done(1);
785 	}
786 	(void) strcat(lnkbuf, buf);
787 }
788 
789 /*
790  * Skip over a hole in a symbolic link (should never happen).
791  */
792 /* ARGSUSED */
793 static void
794 xtrlnkskip(char *buf, long size)
795 {
796 
797 	fprintf(stderr, "unallocated block in symbolic link %s\n",
798 		curfile.name);
799 	done(1);
800 }
801 
802 /*
803  * Collect the next block of a bit map.
804  */
805 static void
806 xtrmap(char *buf, long size)
807 {
808 
809 	memmove(map, buf, size);
810 	map += size;
811 }
812 
813 /*
814  * Skip over a hole in a bit map (should never happen).
815  */
816 /* ARGSUSED */
817 static void
818 xtrmapskip(char *buf, long size)
819 {
820 
821 	panic("hole in map\n");
822 	map += size;
823 }
824 
825 /*
826  * Noop, when an extraction function is not needed.
827  */
828 /* ARGSUSED */
829 void
830 xtrnull(char *buf, long size)
831 {
832 
833 	return;
834 }
835 
836 /*
837  * Read TP_BSIZE blocks from the input.
838  * Handle read errors, and end of media.
839  */
840 static void
841 readtape(char *buf)
842 {
843 	long rd, newvol, i;
844 	int cnt, seek_failed;
845 
846 	if (blkcnt < numtrec) {
847 		memmove(buf, &tapebuf[(blkcnt++ * TP_BSIZE)], (long)TP_BSIZE);
848 		blksread++;
849 		tapeaddr++;
850 		return;
851 	}
852 	for (i = 0; i < ntrec; i++)
853 		((struct s_spcl *)&tapebuf[i * TP_BSIZE])->c_magic = 0;
854 	if (numtrec == 0)
855 		numtrec = ntrec;
856 	cnt = ntrec * TP_BSIZE;
857 	rd = 0;
858 getmore:
859 #ifdef RRESTORE
860 	if (host)
861 		i = rmtread(&tapebuf[rd], cnt);
862 	else
863 #endif
864 		i = read(mt, &tapebuf[rd], cnt);
865 	/*
866 	 * Check for mid-tape short read error.
867 	 * If found, skip rest of buffer and start with the next.
868 	 */
869 	if (!pipein && numtrec < ntrec && i > 0) {
870 		dprintf(stdout, "mid-media short read error.\n");
871 		numtrec = ntrec;
872 	}
873 	/*
874 	 * Handle partial block read.
875 	 */
876 	if (pipein && i == 0 && rd > 0)
877 		i = rd;
878 	else if (i > 0 && i != ntrec * TP_BSIZE) {
879 		if (pipein) {
880 			rd += i;
881 			cnt -= i;
882 			if (cnt > 0)
883 				goto getmore;
884 			i = rd;
885 		} else {
886 			/*
887 			 * Short read. Process the blocks read.
888 			 */
889 			if (i % TP_BSIZE != 0)
890 				vprintf(stdout,
891 				    "partial block read: %ld should be %ld\n",
892 				    i, ntrec * TP_BSIZE);
893 			numtrec = i / TP_BSIZE;
894 		}
895 	}
896 	/*
897 	 * Handle read error.
898 	 */
899 	if (i < 0) {
900 		fprintf(stderr, "Tape read error while ");
901 		switch (curfile.action) {
902 		default:
903 			fprintf(stderr, "trying to set up tape\n");
904 			break;
905 		case UNKNOWN:
906 			fprintf(stderr, "trying to resynchronize\n");
907 			break;
908 		case USING:
909 			fprintf(stderr, "restoring %s\n", curfile.name);
910 			break;
911 		case SKIP:
912 			fprintf(stderr, "skipping over inode %d\n",
913 				curfile.ino);
914 			break;
915 		}
916 		if (!yflag && !reply("continue"))
917 			done(1);
918 		i = ntrec * TP_BSIZE;
919 		memset(tapebuf, 0, i);
920 #ifdef RRESTORE
921 		if (host)
922 			seek_failed = (rmtseek(i, 1) < 0);
923 		else
924 #endif
925 			seek_failed = (lseek(mt, i, SEEK_CUR) == (off_t)-1);
926 
927 		if (seek_failed) {
928 			fprintf(stderr,
929 			    "continuation failed: %s\n", strerror(errno));
930 			done(1);
931 		}
932 	}
933 	/*
934 	 * Handle end of tape.
935 	 */
936 	if (i == 0) {
937 		vprintf(stdout, "End-of-tape encountered\n");
938 		if (!pipein) {
939 			newvol = volno + 1;
940 			volno = 0;
941 			numtrec = 0;
942 			getvol(newvol);
943 			readtape(buf);
944 			return;
945 		}
946 		if (rd % TP_BSIZE != 0)
947 			panic("partial block read: %d should be %d\n",
948 				rd, ntrec * TP_BSIZE);
949 		terminateinput();
950 		memmove(&tapebuf[rd], &endoftapemark, (long)TP_BSIZE);
951 	}
952 	blkcnt = 0;
953 	memmove(buf, &tapebuf[(blkcnt++ * TP_BSIZE)], (long)TP_BSIZE);
954 	blksread++;
955 	tapeaddr++;
956 }
957 
958 static void
959 findtapeblksize(void)
960 {
961 	long i;
962 
963 	for (i = 0; i < ntrec; i++)
964 		((struct s_spcl *)&tapebuf[i * TP_BSIZE])->c_magic = 0;
965 	blkcnt = 0;
966 #ifdef RRESTORE
967 	if (host)
968 		i = rmtread(tapebuf, ntrec * TP_BSIZE);
969 	else
970 #endif
971 		i = read(mt, tapebuf, ntrec * TP_BSIZE);
972 
973 	if (i <= 0) {
974 		fprintf(stderr, "tape read error: %s\n", strerror(errno));
975 		done(1);
976 	}
977 	if (i % TP_BSIZE != 0) {
978 		fprintf(stderr, "Tape block size (%ld) %s (%d)\n",
979 			i, "is not a multiple of dump block size", TP_BSIZE);
980 		done(1);
981 	}
982 	ntrec = i / TP_BSIZE;
983 	numtrec = ntrec;
984 	vprintf(stdout, "Tape block size is %ld\n", ntrec);
985 }
986 
987 void
988 closemt(void)
989 {
990 
991 	if (mt < 0)
992 		return;
993 #ifdef RRESTORE
994 	if (host)
995 		rmtclose();
996 	else
997 #endif
998 		(void) close(mt);
999 }
1000 
1001 /*
1002  * Read the next block from the tape.
1003  * Check to see if it is one of several vintage headers.
1004  * If it is an old style header, convert it to a new style header.
1005  * If it is not any valid header, return an error.
1006  */
1007 static int
1008 gethead(struct s_spcl *buf)
1009 {
1010 	long i;
1011 	union {
1012 		quad_t	qval;
1013 		int32_t	val[2];
1014 	} qcvt;
1015 	union u_ospcl {
1016 		char dummy[TP_BSIZE];
1017 		struct	s_ospcl {
1018 			int32_t	c_type;
1019 			int32_t	c_date;
1020 			int32_t	c_ddate;
1021 			int32_t	c_volume;
1022 			int32_t	c_tapea;
1023 			u_short	c_inumber;
1024 			int32_t	c_magic;
1025 			int32_t	c_checksum;
1026 			struct odinode {
1027 				unsigned short odi_mode;
1028 				u_short	odi_nlink;
1029 				u_short	odi_uid;
1030 				u_short	odi_gid;
1031 				int32_t	odi_size;
1032 				int32_t	odi_rdev;
1033 				char	odi_addr[36];
1034 				int32_t	odi_atime;
1035 				int32_t	odi_mtime;
1036 				int32_t	odi_ctime;
1037 			} c_dinode;
1038 			int32_t	c_count;
1039 			char	c_addr[256];
1040 		} s_ospcl;
1041 	} u_ospcl;
1042 
1043 	if (!cvtflag) {
1044 		readtape((char *)buf);
1045 		if (buf->c_magic != NFS_MAGIC) {
1046 			if (swabl(buf->c_magic) != NFS_MAGIC)
1047 				return (FAIL);
1048 			if (!Bcvt) {
1049 				vprintf(stdout, "Note: Doing Byte swapping\n");
1050 				Bcvt = 1;
1051 			}
1052 		}
1053 		if (checksum((int *)buf) == FAIL)
1054 			return (FAIL);
1055 		if (Bcvt) {
1056 			swabst((u_char *)"8l4s31l", (u_char *)buf);
1057 			swabst((u_char *)"l",(u_char *) &buf->c_level);
1058 			swabst((u_char *)"2l",(u_char *) &buf->c_flags);
1059 		}
1060 		goto good;
1061 	}
1062 	readtape((char *)(&u_ospcl.s_ospcl));
1063 	memset(buf, 0, (long)TP_BSIZE);
1064 	buf->c_type = u_ospcl.s_ospcl.c_type;
1065 	buf->c_date = u_ospcl.s_ospcl.c_date;
1066 	buf->c_ddate = u_ospcl.s_ospcl.c_ddate;
1067 	buf->c_volume = u_ospcl.s_ospcl.c_volume;
1068 	buf->c_tapea = u_ospcl.s_ospcl.c_tapea;
1069 	buf->c_inumber = u_ospcl.s_ospcl.c_inumber;
1070 	buf->c_checksum = u_ospcl.s_ospcl.c_checksum;
1071 	buf->c_magic = u_ospcl.s_ospcl.c_magic;
1072 	buf->c_dinode.di_mode = u_ospcl.s_ospcl.c_dinode.odi_mode;
1073 	buf->c_dinode.di_nlink = u_ospcl.s_ospcl.c_dinode.odi_nlink;
1074 	buf->c_dinode.di_uid = u_ospcl.s_ospcl.c_dinode.odi_uid;
1075 	buf->c_dinode.di_gid = u_ospcl.s_ospcl.c_dinode.odi_gid;
1076 	buf->c_dinode.di_size = u_ospcl.s_ospcl.c_dinode.odi_size;
1077 	buf->c_dinode.di_rdev = u_ospcl.s_ospcl.c_dinode.odi_rdev;
1078 	buf->c_dinode.di_atime = u_ospcl.s_ospcl.c_dinode.odi_atime;
1079 	buf->c_dinode.di_mtime = u_ospcl.s_ospcl.c_dinode.odi_mtime;
1080 	buf->c_dinode.di_ctime = u_ospcl.s_ospcl.c_dinode.odi_ctime;
1081 	buf->c_count = u_ospcl.s_ospcl.c_count;
1082 	memmove(buf->c_addr, u_ospcl.s_ospcl.c_addr, (long)256);
1083 	if (u_ospcl.s_ospcl.c_magic != OFS_MAGIC ||
1084 	    checksum((int *)(&u_ospcl.s_ospcl)) == FAIL)
1085 		return(FAIL);
1086 	buf->c_magic = NFS_MAGIC;
1087 
1088 good:
1089 	if ((buf->c_dinode.di_size == 0 || buf->c_dinode.di_size > 0xfffffff) &&
1090 	    (buf->c_dinode.di_mode & IFMT) == IFDIR && Qcvt == 0) {
1091 		qcvt.qval = buf->c_dinode.di_size;
1092 		if (qcvt.val[0] || qcvt.val[1]) {
1093 			printf("Note: Doing Quad swapping\n");
1094 			Qcvt = 1;
1095 		}
1096 	}
1097 	if (Qcvt) {
1098 		qcvt.qval = buf->c_dinode.di_size;
1099 		i = qcvt.val[1];
1100 		qcvt.val[1] = qcvt.val[0];
1101 		qcvt.val[0] = i;
1102 		buf->c_dinode.di_size = qcvt.qval;
1103 	}
1104 	readmapflag = 0;
1105 
1106 	switch (buf->c_type) {
1107 
1108 	case TS_CLRI:
1109 	case TS_BITS:
1110 		/*
1111 		 * Have to patch up missing information in bit map headers
1112 		 */
1113 		buf->c_inumber = 0;
1114 		buf->c_dinode.di_size = buf->c_count * TP_BSIZE;
1115 		if (buf->c_count > TP_NINDIR)
1116 			readmapflag = 1;
1117 		else
1118 			for (i = 0; i < buf->c_count; i++)
1119 				buf->c_addr[i]++;
1120 		break;
1121 
1122 	case TS_TAPE:
1123 		if ((buf->c_flags & DR_NEWINODEFMT) == 0)
1124 			oldinofmt = 1;
1125 		/* fall through */
1126 	case TS_END:
1127 		buf->c_inumber = 0;
1128 		break;
1129 
1130 	case TS_INODE:
1131 	case TS_ADDR:
1132 		break;
1133 
1134 	default:
1135 		panic("gethead: unknown inode type %d\n", buf->c_type);
1136 		break;
1137 	}
1138 	/*
1139 	 * If we are restoring a filesystem with old format inodes,
1140 	 * copy the uid/gid to the new location.
1141 	 */
1142 	if (oldinofmt) {
1143 		buf->c_dinode.di_uid = buf->c_dinode.di_ouid;
1144 		buf->c_dinode.di_gid = buf->c_dinode.di_ogid;
1145 	}
1146 	tapeaddr = buf->c_tapea;
1147 	if (dflag)
1148 		accthdr(buf);
1149 	return(GOOD);
1150 }
1151 
1152 /*
1153  * Check that a header is where it belongs and predict the next header
1154  */
1155 static void
1156 accthdr(struct s_spcl *header)
1157 {
1158 	static ino_t previno = 0x7fffffff;
1159 	static int prevtype;
1160 	static long predict;
1161 	long blks, i;
1162 
1163 	if (header->c_type == TS_TAPE) {
1164 		fprintf(stderr, "Volume header (%s inode format) ",
1165 		    oldinofmt ? "old" : "new");
1166  		if (header->c_firstrec)
1167  			fprintf(stderr, "begins with record %ld",
1168  				header->c_firstrec);
1169  		fprintf(stderr, "\n");
1170 		previno = 0x7fffffff;
1171 		return;
1172 	}
1173 	if (previno == 0x7fffffff)
1174 		goto newcalc;
1175 	switch (prevtype) {
1176 	case TS_BITS:
1177 		fprintf(stderr, "Dumped inodes map header");
1178 		break;
1179 	case TS_CLRI:
1180 		fprintf(stderr, "Used inodes map header");
1181 		break;
1182 	case TS_INODE:
1183 		fprintf(stderr, "File header, ino %d", previno);
1184 		break;
1185 	case TS_ADDR:
1186 		fprintf(stderr, "File continuation header, ino %d", previno);
1187 		break;
1188 	case TS_END:
1189 		fprintf(stderr, "End of tape header");
1190 		break;
1191 	}
1192 	if (predict != blksread - 1)
1193 		fprintf(stderr, "; predicted %ld blocks, got %ld blocks",
1194 			predict, blksread - 1);
1195 	fprintf(stderr, "\n");
1196 newcalc:
1197 	blks = 0;
1198 	if (header->c_type != TS_END)
1199 		for (i = 0; i < header->c_count; i++)
1200 			if (readmapflag || header->c_addr[i] != 0)
1201 				blks++;
1202 	predict = blks;
1203 	blksread = 0;
1204 	prevtype = header->c_type;
1205 	previno = header->c_inumber;
1206 }
1207 
1208 /*
1209  * Find an inode header.
1210  * Complain if had to skip.
1211  */
1212 static void
1213 findinode(struct s_spcl *header)
1214 {
1215 	static long skipcnt = 0;
1216 	long i;
1217 	char buf[TP_BSIZE];
1218 	int htype;
1219 
1220 	curfile.name = "<name unknown>";
1221 	curfile.action = UNKNOWN;
1222 	curfile.dip = NULL;
1223 	curfile.ino = 0;
1224 	do {
1225 		if (header->c_magic != NFS_MAGIC) {
1226 			skipcnt++;
1227 			while (gethead(header) == FAIL ||
1228 			    _time32_to_time(header->c_date) != dumpdate)
1229 				skipcnt++;
1230 		}
1231 		htype = header->c_type;
1232 		switch (htype) {
1233 
1234 		case TS_ADDR:
1235 			/*
1236 			 * Skip up to the beginning of the next record
1237 			 */
1238 			for (i = 0; i < header->c_count; i++)
1239 				if (header->c_addr[i])
1240 					readtape(buf);
1241 			while (gethead(header) == FAIL ||
1242 			    _time32_to_time(header->c_date) != dumpdate)
1243 				skipcnt++;
1244 			break;
1245 
1246 		case TS_INODE:
1247 			curfile.dip = &header->c_dinode;
1248 			curfile.ino = header->c_inumber;
1249 			break;
1250 
1251 		case TS_END:
1252 			/* If we missed some tapes, get another volume. */
1253 			if (tapesread & (tapesread + 1)) {
1254 				getvol(0);
1255 				continue;
1256 			}
1257 			curfile.ino = maxino;
1258 			break;
1259 
1260 		case TS_CLRI:
1261 			curfile.name = "<file removal list>";
1262 			break;
1263 
1264 		case TS_BITS:
1265 			curfile.name = "<file dump list>";
1266 			break;
1267 
1268 		case TS_TAPE:
1269 			panic("unexpected tape header\n");
1270 			/* NOTREACHED */
1271 
1272 		default:
1273 			panic("unknown tape header type %d\n", spcl.c_type);
1274 			/* NOTREACHED */
1275 
1276 		}
1277 	} while (htype == TS_ADDR);
1278 	if (skipcnt > 0)
1279 		fprintf(stderr, "resync restore, skipped %ld blocks\n",
1280 		    skipcnt);
1281 	skipcnt = 0;
1282 }
1283 
1284 static int
1285 checksum(int *buf)
1286 {
1287 	int i, j;
1288 
1289 	j = sizeof(union u_spcl) / sizeof(int);
1290 	i = 0;
1291 	if(!Bcvt) {
1292 		do
1293 			i += *buf++;
1294 		while (--j);
1295 	} else {
1296 		/* What happens if we want to read restore tapes
1297 			for a 16bit int machine??? */
1298 		do
1299 			i += swabl(*buf++);
1300 		while (--j);
1301 	}
1302 
1303 	if (i != CHECKSUM) {
1304 		fprintf(stderr, "Checksum error %o, inode %d file %s\n", i,
1305 			curfile.ino, curfile.name);
1306 		return(FAIL);
1307 	}
1308 	return(GOOD);
1309 }
1310 
1311 #ifdef RRESTORE
1312 #include <stdarg.h>
1313 
1314 void
1315 msg(const char *fmt, ...)
1316 {
1317 	va_list ap;
1318 	va_start(ap, fmt);
1319 	(void)vfprintf(stderr, fmt, ap);
1320 	va_end(ap);
1321 }
1322 #endif /* RRESTORE */
1323 
1324 static u_char *
1325 swabshort(u_char *sp, int n)
1326 {
1327 	char c;
1328 
1329 	while (--n >= 0) {
1330 		c = sp[0]; sp[0] = sp[1]; sp[1] = c;
1331 		sp += 2;
1332 	}
1333 	return (sp);
1334 }
1335 
1336 static u_char *
1337 swablong(u_char *sp, int n)
1338 {
1339 	char c;
1340 
1341 	while (--n >= 0) {
1342 		c = sp[0]; sp[0] = sp[3]; sp[3] = c;
1343 		c = sp[2]; sp[2] = sp[1]; sp[1] = c;
1344 		sp += 4;
1345 	}
1346 	return (sp);
1347 }
1348 
1349 void
1350 swabst(u_char *cp, u_char *sp)
1351 {
1352 	int n = 0;
1353 
1354 	while (*cp) {
1355 		switch (*cp) {
1356 		case '0': case '1': case '2': case '3': case '4':
1357 		case '5': case '6': case '7': case '8': case '9':
1358 			n = (n * 10) + (*cp++ - '0');
1359 			continue;
1360 
1361 		case 's': case 'w': case 'h':
1362 			if (n == 0)
1363 				n = 1;
1364 			sp = swabshort(sp, n);
1365 			break;
1366 
1367 		case 'l':
1368 			if (n == 0)
1369 				n = 1;
1370 			sp = swablong(sp, n);
1371 			break;
1372 
1373 		default: /* Any other character, like 'b' counts as byte. */
1374 			if (n == 0)
1375 				n = 1;
1376 			sp += n;
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