xref: /dragonfly/sbin/restore/tape.c (revision 279dd846)
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. 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  * @(#)tape.c	8.9 (Berkeley) 5/1/95
35  * $FreeBSD: src/sbin/restore/tape.c,v 1.16.2.8 2002/06/30 22:57:52 iedowse Exp $
36  * $DragonFly: src/sbin/restore/tape.c,v 1.9 2005/11/06 12:49:25 swildner Exp $
37  */
38 
39 #include <sys/param.h>
40 #include <sys/file.h>
41 #include <sys/mtio.h>
42 #include <sys/stat.h>
43 #include <sys/time.h>
44 
45 #include <vfs/ufs/dinode.h>
46 #include <protocols/dumprestore.h>
47 
48 #include <errno.h>
49 #include <paths.h>
50 #include <setjmp.h>
51 #include <stdio.h>
52 #include <stdlib.h>
53 #include <string.h>
54 #include <time.h>
55 #include <unistd.h>
56 
57 #include "restore.h"
58 #include "extern.h"
59 
60 static long	fssize = MAXBSIZE;
61 static int	mt = -1;
62 static int	pipein = 0;
63 static char	*magtape;
64 static int	blkcnt;
65 static int	numtrec;
66 static char	*tapebuf;
67 static union	u_spcl endoftapemark;
68 static long	blksread;		/* blocks read since last header */
69 static long	tapeaddr = 0;		/* current TP_BSIZE tape record */
70 static long	tapesread;
71 static jmp_buf	restart;
72 static int	gettingfile = 0;	/* restart has a valid frame */
73 static char	*host = NULL;
74 
75 static int	ofile;
76 static char	*map;
77 static char	lnkbuf[MAXPATHLEN + 1];
78 static int	pathlen;
79 
80 int		oldinofmt;	/* old inode format conversion required */
81 int		Bcvt;		/* Swap Bytes (for CCI or sun) */
82 static int	Qcvt;		/* Swap quads (for sun) */
83 
84 #define	FLUSHTAPEBUF()	blkcnt = ntrec + 1
85 
86 static void	 accthdr(struct s_spcl *);
87 static int	 checksum(int *);
88 static void	 findinode(struct s_spcl *);
89 static void	 findtapeblksize(void);
90 static int	 gethead(struct s_spcl *);
91 static void	 readtape(char *);
92 static void	 setdumpnum(void);
93 static u_long	 swabl(u_long);
94 static u_char	*swablong(u_char *, int);
95 static u_char	*swabshort(u_char *, int);
96 static void	 terminateinput(void);
97 static void	 xtrfile(char *, long);
98 static void	 xtrlnkfile(char *, long);
99 static void	 xtrlnkskip(char *, long);
100 static void	 xtrmap(char *, long);
101 static void	 xtrmapskip(char *, long);
102 static void	 xtrskip(char *, long);
103 
104 static int readmapflag;
105 
106 /*
107  * Set up an input source
108  */
109 void
110 setinput(char *source)
111 {
112 	FLUSHTAPEBUF();
113 	if (bflag)
114 		newtapebuf(ntrec);
115 	else
116 		newtapebuf(NTREC > HIGHDENSITYTREC ? NTREC : HIGHDENSITYTREC);
117 	terminal = stdin;
118 
119 #ifdef RRESTORE
120 	if (strchr(source, ':')) {
121 		host = source;
122 		source = strchr(host, ':');
123 		*source++ = '\0';
124 		if (rmthost(host) == 0)
125 			done(1);
126 	} else
127 #endif
128 	if (strcmp(source, "-") == 0) {
129 		/*
130 		 * Since input is coming from a pipe we must establish
131 		 * our own connection to the terminal.
132 		 */
133 		terminal = fopen(_PATH_TTY, "r");
134 		if (terminal == NULL) {
135 			fprintf(stderr, "cannot open %s: %s\n",
136 			    _PATH_TTY, strerror(errno));
137 			terminal = fopen(_PATH_DEVNULL, "r");
138 			if (terminal == NULL) {
139 				fprintf(stderr, "cannot open %s: %s\n",
140 				    _PATH_DEVNULL, strerror(errno));
141 				done(1);
142 			}
143 		}
144 		pipein++;
145 	}
146 	setuid(getuid());	/* no longer need or want root privileges */
147 	magtape = strdup(source);
148 	if (magtape == NULL) {
149 		fprintf(stderr, "Cannot allocate space for magtape buffer\n");
150 		done(1);
151 	}
152 }
153 
154 void
155 newtapebuf(long size)
156 {
157 	static long tapebufsize = -1;
158 
159 	ntrec = size;
160 	if (size <= tapebufsize)
161 		return;
162 	if (tapebuf != NULL)
163 		free(tapebuf);
164 	tapebuf = malloc(size * TP_BSIZE);
165 	if (tapebuf == NULL) {
166 		fprintf(stderr, "Cannot allocate space for tape buffer\n");
167 		done(1);
168 	}
169 	tapebufsize = size;
170 }
171 
172 /*
173  * Verify that the tape drive can be accessed and
174  * that it actually is a dump tape.
175  */
176 void
177 setup(void)
178 {
179 	int i, j, *ip;
180 	struct stat stbuf;
181 
182 	vprintf(stdout, "Verify tape and initialize maps\n");
183 #ifdef RRESTORE
184 	if (host)
185 		mt = rmtopen(magtape, 0);
186 	else
187 #endif
188 	if (pipein)
189 		mt = 0;
190 	else
191 		mt = open(magtape, O_RDONLY, 0);
192 	if (mt < 0) {
193 		fprintf(stderr, "%s: %s\n", magtape, strerror(errno));
194 		done(1);
195 	}
196 	volno = 1;
197 	setdumpnum();
198 	FLUSHTAPEBUF();
199 	if (!pipein && !bflag)
200 		findtapeblksize();
201 	if (gethead(&spcl) == FAIL) {
202 		blkcnt--; /* push back this block */
203 		blksread--;
204 		cvtflag++;
205 		if (gethead(&spcl) == FAIL) {
206 			fprintf(stderr, "Tape is not a dump tape\n");
207 			done(1);
208 		}
209 		fprintf(stderr, "Converting to new file system format.\n");
210 	}
211 	if (pipein) {
212 		endoftapemark.s_spcl.c_magic = cvtflag ? OFS_MAGIC : NFS_MAGIC;
213 		endoftapemark.s_spcl.c_type = TS_END;
214 		ip = (int *)&endoftapemark;
215 		j = sizeof(union u_spcl) / sizeof(int);
216 		i = 0;
217 		do
218 			i += *ip++;
219 		while (--j);
220 		endoftapemark.s_spcl.c_checksum = CHECKSUM - i;
221 	}
222 	if (vflag || command == 't')
223 		printdumpinfo();
224 	dumptime = spcl.c_ddate;
225 	dumpdate = spcl.c_date;
226 	if (stat(".", &stbuf) < 0) {
227 		fprintf(stderr, "cannot stat .: %s\n", strerror(errno));
228 		done(1);
229 	}
230 	if (stbuf.st_blksize > 0 && stbuf.st_blksize < TP_BSIZE )
231 		fssize = TP_BSIZE;
232 	if (stbuf.st_blksize >= TP_BSIZE && stbuf.st_blksize <= MAXBSIZE)
233 		fssize = stbuf.st_blksize;
234 	if (((fssize - 1) & fssize) != 0) {
235 		fprintf(stderr, "bad block size %ld\n", fssize);
236 		done(1);
237 	}
238 	if (spcl.c_volume != 1) {
239 		fprintf(stderr, "Tape is not volume 1 of the dump\n");
240 		done(1);
241 	}
242 	if (gethead(&spcl) == FAIL) {
243 		dprintf(stdout, "header read failed at %ld blocks\n", blksread);
244 		panic("no header after volume mark!\n");
245 	}
246 	findinode(&spcl);
247 	if (spcl.c_type != TS_CLRI) {
248 		fprintf(stderr, "Cannot find file removal list\n");
249 		done(1);
250 	}
251 	maxino = (spcl.c_count * TP_BSIZE * NBBY) + 1;
252 	dprintf(stdout, "maxino = %d\n", maxino);
253 	map = calloc((unsigned)1, (unsigned)howmany(maxino, NBBY));
254 	if (map == NULL)
255 		panic("no memory for active inode map\n");
256 	usedinomap = map;
257 	curfile.action = USING;
258 	getfile(xtrmap, xtrmapskip);
259 	if (spcl.c_type != TS_BITS) {
260 		fprintf(stderr, "Cannot find file dump list\n");
261 		done(1);
262 	}
263 	map = calloc((unsigned)1, (unsigned)howmany(maxino, NBBY));
264 	if (map == NULL)
265 		panic("no memory for file dump list\n");
266 	dumpmap = map;
267 	curfile.action = USING;
268 	getfile(xtrmap, xtrmapskip);
269 	/*
270 	 * If there may be whiteout entries on the tape, pretend that the
271 	 * whiteout inode exists, so that the whiteout entries can be
272 	 * extracted.
273 	 */
274 	if (oldinofmt == 0)
275 		SETINO(WINO, dumpmap);
276 	/* 'r' restores don't call getvol() for tape 1, so mark it as read. */
277 	if (command == 'r')
278 		tapesread = 1;
279 }
280 
281 /*
282  * Prompt user to load a new dump volume.
283  * "Nextvol" is the next suggested volume to use.
284  * This suggested volume is enforced when doing full
285  * or incremental restores, but can be overridden by
286  * the user when only extracting a subset of the files.
287  */
288 void
289 getvol(long nextvol)
290 {
291 	long newvol = 0, prevtapea, savecnt, i;
292 	union u_spcl tmpspcl;
293 #	define tmpbuf tmpspcl.s_spcl
294 	char buf[TP_BSIZE];
295 
296 	if (nextvol == 1) {
297 		tapesread = 0;
298 		gettingfile = 0;
299 	}
300 	prevtapea = tapeaddr;
301 	savecnt = blksread;
302 	if (pipein) {
303 		if (nextvol != 1) {
304 			panic("Changing volumes on pipe input?\n");
305 			/* Avoid looping if we couldn't ask the user. */
306 			if (yflag || ferror(terminal) || feof(terminal))
307 				done(1);
308 		}
309 		if (volno == 1)
310 			return;
311 		goto gethdr;
312 	}
313 again:
314 	if (pipein)
315 		done(1); /* pipes do not get a second chance */
316 	if (command == 'R' || command == 'r' || curfile.action != SKIP)
317 		newvol = nextvol;
318 	else
319 		newvol = 0;
320 	while (newvol <= 0) {
321 		if (tapesread == 0) {
322 			fprintf(stderr, "%s%s%s%s%s%s%s",
323 			    "You have not read any tapes yet.\n",
324 			    "If you are extracting just a few files,",
325 			    " start with the last volume\n",
326 			    "and work towards the first; restore",
327 			    " can quickly skip tapes that\n",
328 			    "have no further files to extract.",
329 			    " Otherwise, begin with volume 1.\n");
330 		} else {
331 			fprintf(stderr, "You have read volumes");
332 			strcpy(buf, ": ");
333 			for (i = 0; i < 32; i++)
334 				if (tapesread & (1 << i)) {
335 					fprintf(stderr, "%s%ld", buf, i + 1);
336 					strcpy(buf, ", ");
337 				}
338 			fprintf(stderr, "\n");
339 		}
340 		do	{
341 			fprintf(stderr, "Specify next volume #: ");
342 			fflush(stderr);
343 			if (fgets(buf, BUFSIZ, terminal) == NULL)
344 				done(1);
345 		} while (buf[0] == '\n');
346 		newvol = atoi(buf);
347 		if (newvol <= 0) {
348 			fprintf(stderr,
349 			    "Volume numbers are positive numerics\n");
350 		}
351 	}
352 	if (newvol == volno) {
353 		tapesread |= 1 << (volno - 1);
354 		return;
355 	}
356 	closemt();
357 	fprintf(stderr, "Mount tape volume %ld\n", newvol);
358 	fprintf(stderr, "Enter ``none'' if there are no more tapes\n");
359 	fprintf(stderr, "otherwise enter tape name (default: %s) ", magtape);
360 	fflush(stderr);
361 	if (fgets(buf, BUFSIZ, terminal) == NULL)
362 		done(1);
363 	if (!strcmp(buf, "none\n")) {
364 		terminateinput();
365 		return;
366 	}
367 	if (buf[0] != '\n') {
368 		strcpy(magtape, buf);
369 		magtape[strlen(magtape) - 1] = '\0';
370 	}
371 #ifdef RRESTORE
372 	if (host)
373 		mt = rmtopen(magtape, 0);
374 	else
375 #endif
376 		mt = open(magtape, O_RDONLY, 0);
377 
378 	if (mt == -1) {
379 		fprintf(stderr, "Cannot open %s\n", magtape);
380 		volno = -1;
381 		goto again;
382 	}
383 gethdr:
384 	volno = newvol;
385 	setdumpnum();
386 	FLUSHTAPEBUF();
387 	if (gethead(&tmpbuf) == FAIL) {
388 		dprintf(stdout, "header read failed at %ld blocks\n", blksread);
389 		fprintf(stderr, "tape is not dump tape\n");
390 		volno = 0;
391 		goto again;
392 	}
393 	if (tmpbuf.c_volume != volno) {
394 		fprintf(stderr, "Wrong volume (%ld)\n", (long)tmpbuf.c_volume);
395 		volno = 0;
396 		goto again;
397 	}
398 	if (tmpbuf.c_date != dumpdate || tmpbuf.c_ddate != dumptime) {
399 		time_t c_date = tmpbuf.c_date;
400 		fprintf(stderr, "Wrong dump date\n\tgot: %s", ctime(&c_date));
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 %ld, tape starts with %ld\n", prevtapea,
415 	    (long)tmpbuf.c_tapea);
416  	if (tmpbuf.c_type == TS_TAPE && (tmpbuf.c_flags & DR_NEWHEADER)) {
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 	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.dip = NULL;
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 c_date = spcl.c_date;
507 	time_t c_ddate = spcl.c_ddate;
508 
509 	fprintf(stdout, "Dump   date: %s", ctime(&c_date));
510 	fprintf(stdout, "Dumped from: %s",
511 	    (spcl.c_ddate == 0) ? "the epoch\n" : ctime(&c_ddate));
512 	if (spcl.c_host[0] == '\0')
513 		return;
514 	fprintf(stderr, "Level %ld dump of %s on %s:%s\n",
515 		(long)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 	uid_t uid;
524 	gid_t gid;
525 	mode_t mode;
526 	struct timeval timep[2];
527 	struct entry *ep;
528 
529 	curfile.name = name;
530 	curfile.action = USING;
531 	timep[0].tv_sec = curfile.dip->di_atime;
532 	timep[0].tv_usec = curfile.dip->di_atimensec / 1000;
533 	timep[1].tv_sec = curfile.dip->di_mtime;
534 	timep[1].tv_usec = curfile.dip->di_mtimensec / 1000;
535 	uid = curfile.dip->di_uid;
536 	gid = curfile.dip->di_gid;
537 	mode = curfile.dip->di_mode;
538 	flags = curfile.dip->di_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 			lchown(name, uid, gid);
573 			lchmod(name, mode);
574 			lutimes(name, timep);
575 			return (GOOD);
576 		}
577 		return (FAIL);
578 
579 	case IFIFO:
580 		vprintf(stdout, "extract fifo %s\n", name);
581 		if (Nflag) {
582 			skipfile();
583 			return (GOOD);
584 		}
585 		if (uflag && !Nflag)
586 			unlink(name);
587 		if (mkfifo(name, mode) < 0) {
588 			fprintf(stderr, "%s: cannot create fifo: %s\n",
589 			    name, strerror(errno));
590 			skipfile();
591 			return (FAIL);
592 		}
593 		chown(name, uid, gid);
594 		chmod(name, mode);
595 		utimes(name, timep);
596 		chflags(name, flags);
597 		skipfile();
598 		return (GOOD);
599 
600 	case IFCHR:
601 	case IFBLK:
602 		vprintf(stdout, "extract special file %s\n", name);
603 		if (Nflag) {
604 			skipfile();
605 			return (GOOD);
606 		}
607 		if (uflag)
608 			unlink(name);
609 		if (mknod(name, mode, (int)curfile.dip->di_rdev) < 0) {
610 			fprintf(stderr, "%s: cannot create special file: %s\n",
611 			    name, strerror(errno));
612 			skipfile();
613 			return (FAIL);
614 		}
615 		chown(name, uid, gid);
616 		chmod(name, mode);
617 		utimes(name, timep);
618 		chflags(name, flags);
619 		skipfile();
620 		return (GOOD);
621 
622 	case IFREG:
623 		vprintf(stdout, "extract file %s\n", name);
624 		if (Nflag) {
625 			skipfile();
626 			return (GOOD);
627 		}
628 		if (uflag)
629 			unlink(name);
630 		if ((ofile = open(name, O_WRONLY | O_CREAT | O_TRUNC,
631 		    0666)) < 0) {
632 			fprintf(stderr, "%s: cannot create file: %s\n",
633 			    name, strerror(errno));
634 			skipfile();
635 			return (FAIL);
636 		}
637 		fchown(ofile, uid, gid);
638 		fchmod(ofile, mode);
639 		getfile(xtrfile, xtrskip);
640 		close(ofile);
641 		utimes(name, timep);
642 		chflags(name, flags);
643 		return (GOOD);
644 	}
645 	/* NOTREACHED */
646 }
647 
648 /*
649  * skip over bit maps on the tape
650  */
651 void
652 skipmaps(void)
653 {
654 
655 	while (spcl.c_type == TS_BITS || spcl.c_type == TS_CLRI)
656 		skipfile();
657 }
658 
659 /*
660  * skip over a file on the tape
661  */
662 void
663 skipfile(void)
664 {
665 
666 	curfile.action = SKIP;
667 	getfile(xtrnull, xtrnull);
668 }
669 
670 /*
671  * Extract a file from the tape.
672  * When an allocated block is found it is passed to the fill function;
673  * when an unallocated block (hole) is found, a zeroed buffer is passed
674  * to the skip function.
675  */
676 void
677 getfile(void (*fill) (char *, long), void (*skip) (char *, long))
678 {
679 	int i;
680 	int curblk = 0;
681 	quad_t size = spcl.c_dinode.di_size;
682 	static char clearedbuf[MAXBSIZE];
683 	char buf[MAXBSIZE / TP_BSIZE][TP_BSIZE];
684 	char junk[TP_BSIZE];
685 
686 	if (spcl.c_type == TS_END)
687 		panic("ran off end of tape\n");
688 	if (spcl.c_magic != NFS_MAGIC)
689 		panic("not at beginning of a file\n");
690 	if (!gettingfile && setjmp(restart) != 0)
691 		return;
692 	gettingfile++;
693 loop:
694 	for (i = 0; i < spcl.c_count; i++) {
695 		if (readmapflag || spcl.c_addr[i]) {
696 			readtape(&buf[curblk++][0]);
697 			if (curblk == fssize / TP_BSIZE) {
698 				(*fill)((char *)buf, (long)(size > TP_BSIZE ?
699 				     fssize : (curblk - 1) * TP_BSIZE + size));
700 				curblk = 0;
701 			}
702 		} else {
703 			if (curblk > 0) {
704 				(*fill)((char *)buf, (long)(size > TP_BSIZE ?
705 				     curblk * TP_BSIZE :
706 				     (curblk - 1) * TP_BSIZE + size));
707 				curblk = 0;
708 			}
709 			(*skip)(clearedbuf, (long)(size > TP_BSIZE ?
710 				TP_BSIZE : size));
711 		}
712 		if ((size -= TP_BSIZE) <= 0) {
713 			for (i++; i < spcl.c_count; i++)
714 				if (readmapflag || spcl.c_addr[i])
715 					readtape(junk);
716 			break;
717 		}
718 	}
719 	if (gethead(&spcl) == GOOD && size > 0) {
720 		if (spcl.c_type == TS_ADDR)
721 			goto loop;
722 		dprintf(stdout,
723 			"Missing address (header) block for %s at %ld blocks\n",
724 			curfile.name, blksread);
725 	}
726 	if (curblk > 0)
727 		(*fill)((char *)buf, (long)((curblk * TP_BSIZE) + size));
728 	findinode(&spcl);
729 	gettingfile = 0;
730 }
731 
732 /*
733  * Write out the next block of a file.
734  */
735 static void
736 xtrfile(char *buf, long size)
737 {
738 
739 	if (Nflag)
740 		return;
741 	if (write(ofile, buf, (int) size) == -1) {
742 		fprintf(stderr,
743 		    "write error extracting inode %d, name %s\nwrite: %s\n",
744 			curfile.ino, curfile.name, strerror(errno));
745 	}
746 }
747 
748 /*
749  * Skip over a hole in a file.
750  */
751 /* ARGSUSED */
752 static void
753 xtrskip(char *buf, long size)
754 {
755 
756 	if (lseek(ofile, size, SEEK_CUR) == -1) {
757 		fprintf(stderr,
758 		    "seek error extracting inode %d, name %s\nlseek: %s\n",
759 			curfile.ino, curfile.name, strerror(errno));
760 		done(1);
761 	}
762 }
763 
764 /*
765  * Collect the next block of a symbolic link.
766  */
767 static void
768 xtrlnkfile(char *buf, long size)
769 {
770 
771 	pathlen += size;
772 	if (pathlen > MAXPATHLEN) {
773 		fprintf(stderr, "symbolic link name: %s->%s%s; too long %d\n",
774 		    curfile.name, lnkbuf, buf, pathlen);
775 		done(1);
776 	}
777 	strcat(lnkbuf, buf);
778 }
779 
780 /*
781  * Skip over a hole in a symbolic link (should never happen).
782  */
783 /* ARGSUSED */
784 static void
785 xtrlnkskip(char *buf, long size)
786 {
787 
788 	fprintf(stderr, "unallocated block in symbolic link %s\n",
789 		curfile.name);
790 	done(1);
791 }
792 
793 /*
794  * Collect the next block of a bit map.
795  */
796 static void
797 xtrmap(char *buf, long size)
798 {
799 
800 	memmove(map, buf, size);
801 	map += size;
802 }
803 
804 /*
805  * Skip over a hole in a bit map (should never happen).
806  */
807 /* ARGSUSED */
808 static void
809 xtrmapskip(char *buf, long size)
810 {
811 
812 	panic("hole in map\n");
813 	map += size;
814 }
815 
816 /*
817  * Noop, when an extraction function is not needed.
818  */
819 /* ARGSUSED */
820 void
821 xtrnull(char *buf, long size)
822 {
823 
824 	return;
825 }
826 
827 /*
828  * Read TP_BSIZE blocks from the input.
829  * Handle read errors, and end of media.
830  */
831 static void
832 readtape(char *buf)
833 {
834 	long rd, newvol, i;
835 	int cnt, seek_failed;
836 
837 	if (blkcnt < numtrec) {
838 		memmove(buf, &tapebuf[(blkcnt++ * TP_BSIZE)], (long)TP_BSIZE);
839 		blksread++;
840 		tapeaddr++;
841 		return;
842 	}
843 	for (i = 0; i < ntrec; i++)
844 		((struct s_spcl *)&tapebuf[i * TP_BSIZE])->c_magic = 0;
845 	if (numtrec == 0)
846 		numtrec = ntrec;
847 	cnt = ntrec * TP_BSIZE;
848 	rd = 0;
849 getmore:
850 #ifdef RRESTORE
851 	if (host)
852 		i = rmtread(&tapebuf[rd], cnt);
853 	else
854 #endif
855 		i = read(mt, &tapebuf[rd], cnt);
856 	/*
857 	 * Check for mid-tape short read error.
858 	 * If found, skip rest of buffer and start with the next.
859 	 */
860 	if (!pipein && numtrec < ntrec && i > 0) {
861 		dprintf(stdout, "mid-media short read error.\n");
862 		numtrec = ntrec;
863 	}
864 	/*
865 	 * Handle partial block read.
866 	 */
867 	if (pipein && i == 0 && rd > 0)
868 		i = rd;
869 	else if (i > 0 && i != ntrec * TP_BSIZE) {
870 		if (pipein) {
871 			rd += i;
872 			cnt -= i;
873 			if (cnt > 0)
874 				goto getmore;
875 			i = rd;
876 		} else {
877 			/*
878 			 * Short read. Process the blocks read.
879 			 */
880 			if (i % TP_BSIZE != 0)
881 				vprintf(stdout,
882 				    "partial block read: %ld should be %ld\n",
883 				    i, ntrec * TP_BSIZE);
884 			numtrec = i / TP_BSIZE;
885 		}
886 	}
887 	/*
888 	 * Handle read error.
889 	 */
890 	if (i < 0) {
891 		fprintf(stderr, "Tape read error while ");
892 		switch (curfile.action) {
893 		default:
894 			fprintf(stderr, "trying to set up tape\n");
895 			break;
896 		case UNKNOWN:
897 			fprintf(stderr, "trying to resynchronize\n");
898 			break;
899 		case USING:
900 			fprintf(stderr, "restoring %s\n", curfile.name);
901 			break;
902 		case SKIP:
903 			fprintf(stderr, "skipping over inode %d\n",
904 				curfile.ino);
905 			break;
906 		}
907 		if (!yflag && !reply("continue"))
908 			done(1);
909 		i = ntrec * TP_BSIZE;
910 		memset(tapebuf, 0, i);
911 #ifdef RRESTORE
912 		if (host)
913 			seek_failed = (rmtseek(i, 1) < 0);
914 		else
915 #endif
916 			seek_failed = (lseek(mt, i, SEEK_CUR) == (off_t)-1);
917 
918 		if (seek_failed) {
919 			fprintf(stderr,
920 			    "continuation failed: %s\n", strerror(errno));
921 			done(1);
922 		}
923 	}
924 	/*
925 	 * Handle end of tape.
926 	 */
927 	if (i == 0) {
928 		vprintf(stdout, "End-of-tape encountered\n");
929 		if (!pipein) {
930 			newvol = volno + 1;
931 			volno = 0;
932 			numtrec = 0;
933 			getvol(newvol);
934 			readtape(buf);
935 			return;
936 		}
937 		if (rd % TP_BSIZE != 0)
938 			panic("partial block read: %d should be %d\n",
939 				rd, ntrec * TP_BSIZE);
940 		terminateinput();
941 		memmove(&tapebuf[rd], &endoftapemark, (long)TP_BSIZE);
942 	}
943 	blkcnt = 0;
944 	memmove(buf, &tapebuf[(blkcnt++ * TP_BSIZE)], (long)TP_BSIZE);
945 	blksread++;
946 	tapeaddr++;
947 }
948 
949 static void
950 findtapeblksize(void)
951 {
952 	long i;
953 
954 	for (i = 0; i < ntrec; i++)
955 		((struct s_spcl *)&tapebuf[i * TP_BSIZE])->c_magic = 0;
956 	blkcnt = 0;
957 #ifdef RRESTORE
958 	if (host)
959 		i = rmtread(tapebuf, ntrec * TP_BSIZE);
960 	else
961 #endif
962 		i = read(mt, tapebuf, ntrec * TP_BSIZE);
963 
964 	if (i <= 0) {
965 		fprintf(stderr, "tape read error: %s\n", strerror(errno));
966 		done(1);
967 	}
968 	if (i % TP_BSIZE != 0) {
969 		fprintf(stderr, "Tape block size (%ld) %s (%d)\n",
970 			i, "is not a multiple of dump block size", TP_BSIZE);
971 		done(1);
972 	}
973 	ntrec = i / TP_BSIZE;
974 	numtrec = ntrec;
975 	vprintf(stdout, "Tape block size is %ld\n", ntrec);
976 }
977 
978 void
979 closemt(void)
980 {
981 
982 	if (mt < 0)
983 		return;
984 #ifdef RRESTORE
985 	if (host)
986 		rmtclose();
987 	else
988 #endif
989 		close(mt);
990 }
991 
992 /*
993  * Read the next block from the tape.
994  * Check to see if it is one of several vintage headers.
995  * If it is an old style header, convert it to a new style header.
996  * If it is not any valid header, return an error.
997  */
998 static int
999 gethead(struct s_spcl *buf)
1000 {
1001 	long i;
1002 	union {
1003 		quad_t	qval;
1004 		int32_t	val[2];
1005 	} qcvt;
1006 	union u_ospcl {
1007 		char dummy[TP_BSIZE];
1008 		struct	s_ospcl {
1009 			int32_t	c_type;
1010 			int32_t	c_date;
1011 			int32_t	c_ddate;
1012 			int32_t	c_volume;
1013 			int32_t	c_tapea;
1014 			u_short	c_inumber;
1015 			int32_t	c_magic;
1016 			int32_t	c_checksum;
1017 			struct odinode {
1018 				unsigned short odi_mode;
1019 				u_short	odi_nlink;
1020 				u_short	odi_uid;
1021 				u_short	odi_gid;
1022 				int32_t	odi_size;
1023 				int32_t	odi_rdev;
1024 				char	odi_addr[36];
1025 				int32_t	odi_atime;
1026 				int32_t	odi_mtime;
1027 				int32_t	odi_ctime;
1028 			} c_dinode;
1029 			int32_t	c_count;
1030 			char	c_addr[256];
1031 		} s_ospcl;
1032 	} u_ospcl;
1033 
1034 	if (!cvtflag) {
1035 		readtape((char *)buf);
1036 		if (buf->c_magic != NFS_MAGIC) {
1037 			if (swabl(buf->c_magic) != NFS_MAGIC)
1038 				return (FAIL);
1039 			if (!Bcvt) {
1040 				vprintf(stdout, "Note: Doing Byte swapping\n");
1041 				Bcvt = 1;
1042 			}
1043 		}
1044 		if (checksum((int *)buf) == FAIL)
1045 			return (FAIL);
1046 		if (Bcvt) {
1047 			swabst((u_char *)"8l4s31l", (u_char *)buf);
1048 			swabst((u_char *)"l",(u_char *) &buf->c_level);
1049 			swabst((u_char *)"2l",(u_char *) &buf->c_flags);
1050 		}
1051 		goto good;
1052 	}
1053 	readtape((char *)(&u_ospcl.s_ospcl));
1054 	memset(buf, 0, (long)TP_BSIZE);
1055 	buf->c_type = u_ospcl.s_ospcl.c_type;
1056 	buf->c_date = u_ospcl.s_ospcl.c_date;
1057 	buf->c_ddate = u_ospcl.s_ospcl.c_ddate;
1058 	buf->c_volume = u_ospcl.s_ospcl.c_volume;
1059 	buf->c_tapea = u_ospcl.s_ospcl.c_tapea;
1060 	buf->c_inumber = u_ospcl.s_ospcl.c_inumber;
1061 	buf->c_checksum = u_ospcl.s_ospcl.c_checksum;
1062 	buf->c_magic = u_ospcl.s_ospcl.c_magic;
1063 	buf->c_dinode.di_mode = u_ospcl.s_ospcl.c_dinode.odi_mode;
1064 	buf->c_dinode.di_nlink = u_ospcl.s_ospcl.c_dinode.odi_nlink;
1065 	buf->c_dinode.di_uid = u_ospcl.s_ospcl.c_dinode.odi_uid;
1066 	buf->c_dinode.di_gid = u_ospcl.s_ospcl.c_dinode.odi_gid;
1067 	buf->c_dinode.di_size = u_ospcl.s_ospcl.c_dinode.odi_size;
1068 	buf->c_dinode.di_rdev = u_ospcl.s_ospcl.c_dinode.odi_rdev;
1069 	buf->c_dinode.di_atime = u_ospcl.s_ospcl.c_dinode.odi_atime;
1070 	buf->c_dinode.di_mtime = u_ospcl.s_ospcl.c_dinode.odi_mtime;
1071 	buf->c_dinode.di_ctime = u_ospcl.s_ospcl.c_dinode.odi_ctime;
1072 	buf->c_count = u_ospcl.s_ospcl.c_count;
1073 	memmove(buf->c_addr, u_ospcl.s_ospcl.c_addr, (long)256);
1074 	if (u_ospcl.s_ospcl.c_magic != OFS_MAGIC ||
1075 	    checksum((int *)(&u_ospcl.s_ospcl)) == FAIL)
1076 		return(FAIL);
1077 	buf->c_magic = NFS_MAGIC;
1078 
1079 good:
1080 	if ((buf->c_dinode.di_size == 0 || buf->c_dinode.di_size > 0xfffffff) &&
1081 	    (buf->c_dinode.di_mode & IFMT) == IFDIR && Qcvt == 0) {
1082 		qcvt.qval = buf->c_dinode.di_size;
1083 		if (qcvt.val[0] || qcvt.val[1]) {
1084 			printf("Note: Doing Quad swapping\n");
1085 			Qcvt = 1;
1086 		}
1087 	}
1088 	if (Qcvt) {
1089 		qcvt.qval = buf->c_dinode.di_size;
1090 		i = qcvt.val[1];
1091 		qcvt.val[1] = qcvt.val[0];
1092 		qcvt.val[0] = i;
1093 		buf->c_dinode.di_size = qcvt.qval;
1094 	}
1095 	readmapflag = 0;
1096 
1097 	switch (buf->c_type) {
1098 
1099 	case TS_CLRI:
1100 	case TS_BITS:
1101 		/*
1102 		 * Have to patch up missing information in bit map headers
1103 		 */
1104 		buf->c_inumber = 0;
1105 		buf->c_dinode.di_size = buf->c_count * TP_BSIZE;
1106 		if (buf->c_count > TP_NINDIR)
1107 			readmapflag = 1;
1108 		else
1109 			for (i = 0; i < buf->c_count; i++)
1110 				buf->c_addr[i]++;
1111 		break;
1112 
1113 	case TS_TAPE:
1114 		if ((buf->c_flags & DR_NEWINODEFMT) == 0)
1115 			oldinofmt = 1;
1116 		/* fall through */
1117 	case TS_END:
1118 		buf->c_inumber = 0;
1119 		break;
1120 
1121 	case TS_INODE:
1122 	case TS_ADDR:
1123 		break;
1124 
1125 	default:
1126 		panic("gethead: unknown inode type %d\n", buf->c_type);
1127 		break;
1128 	}
1129 	/*
1130 	 * If we are restoring a filesystem with old format inodes,
1131 	 * copy the uid/gid to the new location.
1132 	 */
1133 	if (oldinofmt) {
1134 		buf->c_dinode.di_uid = buf->c_dinode.di_ouid;
1135 		buf->c_dinode.di_gid = buf->c_dinode.di_ogid;
1136 	}
1137 	tapeaddr = buf->c_tapea;
1138 	if (dflag)
1139 		accthdr(buf);
1140 	return(GOOD);
1141 }
1142 
1143 /*
1144  * Check that a header is where it belongs and predict the next header
1145  */
1146 static void
1147 accthdr(struct s_spcl *header)
1148 {
1149 	static ufs1_ino_t previno = 0x7fffffff;
1150 	static int prevtype;
1151 	static long predict;
1152 	long blks, i;
1153 
1154 	if (header->c_type == TS_TAPE) {
1155 		fprintf(stderr, "Volume header (%s inode format) ",
1156 		    oldinofmt ? "old" : "new");
1157  		if (header->c_firstrec)
1158  			fprintf(stderr, "begins with record %ld",
1159  				(long)header->c_firstrec);
1160  		fprintf(stderr, "\n");
1161 		previno = 0x7fffffff;
1162 		return;
1163 	}
1164 	if (previno == 0x7fffffff)
1165 		goto newcalc;
1166 	switch (prevtype) {
1167 	case TS_BITS:
1168 		fprintf(stderr, "Dumped inodes map header");
1169 		break;
1170 	case TS_CLRI:
1171 		fprintf(stderr, "Used inodes map header");
1172 		break;
1173 	case TS_INODE:
1174 		fprintf(stderr, "File header, ino %d", previno);
1175 		break;
1176 	case TS_ADDR:
1177 		fprintf(stderr, "File continuation header, ino %d", previno);
1178 		break;
1179 	case TS_END:
1180 		fprintf(stderr, "End of tape header");
1181 		break;
1182 	}
1183 	if (predict != blksread - 1)
1184 		fprintf(stderr, "; predicted %ld blocks, got %ld blocks",
1185 			predict, blksread - 1);
1186 	fprintf(stderr, "\n");
1187 newcalc:
1188 	blks = 0;
1189 	if (header->c_type != TS_END)
1190 		for (i = 0; i < header->c_count; i++)
1191 			if (readmapflag || header->c_addr[i] != 0)
1192 				blks++;
1193 	predict = blks;
1194 	blksread = 0;
1195 	prevtype = header->c_type;
1196 	previno = header->c_inumber;
1197 }
1198 
1199 /*
1200  * Find an inode header.
1201  * Complain if had to skip.
1202  */
1203 static void
1204 findinode(struct s_spcl *header)
1205 {
1206 	static long skipcnt = 0;
1207 	long i;
1208 	char buf[TP_BSIZE];
1209 	int htype;
1210 
1211 	curfile.name = "<name unknown>";
1212 	curfile.action = UNKNOWN;
1213 	curfile.dip = NULL;
1214 	curfile.ino = 0;
1215 	do {
1216 		if (header->c_magic != NFS_MAGIC) {
1217 			skipcnt++;
1218 			while (gethead(header) == FAIL ||
1219 			    header->c_date != dumpdate)
1220 				skipcnt++;
1221 		}
1222 		htype = header->c_type;
1223 		switch (htype) {
1224 
1225 		case TS_ADDR:
1226 			/*
1227 			 * Skip up to the beginning of the next record
1228 			 */
1229 			for (i = 0; i < header->c_count; i++)
1230 				if (header->c_addr[i])
1231 					readtape(buf);
1232 			while (gethead(header) == FAIL ||
1233 			    header->c_date != dumpdate)
1234 				skipcnt++;
1235 			break;
1236 
1237 		case TS_INODE:
1238 			curfile.dip = &header->c_dinode;
1239 			curfile.ino = header->c_inumber;
1240 			break;
1241 
1242 		case TS_END:
1243 			/* If we missed some tapes, get another volume. */
1244 			if (tapesread & (tapesread + 1)) {
1245 				getvol(0);
1246 				continue;
1247 			}
1248 			curfile.ino = maxino;
1249 			break;
1250 
1251 		case TS_CLRI:
1252 			curfile.name = "<file removal list>";
1253 			break;
1254 
1255 		case TS_BITS:
1256 			curfile.name = "<file dump list>";
1257 			break;
1258 
1259 		case TS_TAPE:
1260 			panic("unexpected tape header\n");
1261 			/* NOTREACHED */
1262 
1263 		default:
1264 			panic("unknown tape header type %d\n", spcl.c_type);
1265 			/* NOTREACHED */
1266 
1267 		}
1268 	} while (htype == TS_ADDR);
1269 	if (skipcnt > 0)
1270 		fprintf(stderr, "resync restore, skipped %ld blocks\n",
1271 		    skipcnt);
1272 	skipcnt = 0;
1273 }
1274 
1275 static int
1276 checksum(int *buf)
1277 {
1278 	int i, j;
1279 
1280 	j = sizeof(union u_spcl) / sizeof(int);
1281 	i = 0;
1282 	if(!Bcvt) {
1283 		do
1284 			i += *buf++;
1285 		while (--j);
1286 	} else {
1287 		/* What happens if we want to read restore tapes
1288 			for a 16bit int machine??? */
1289 		do
1290 			i += swabl(*buf++);
1291 		while (--j);
1292 	}
1293 
1294 	if (i != CHECKSUM) {
1295 		fprintf(stderr, "Checksum error %o, inode %d file %s\n", i,
1296 			curfile.ino, curfile.name);
1297 		return(FAIL);
1298 	}
1299 	return(GOOD);
1300 }
1301 
1302 #ifdef RRESTORE
1303 #include <stdarg.h>
1304 
1305 void
1306 msg(const char *fmt, ...)
1307 {
1308 	va_list ap;
1309 	va_start(ap, fmt);
1310 	vfprintf(stderr, fmt, ap);
1311 	va_end(ap);
1312 }
1313 #endif /* RRESTORE */
1314 
1315 static u_char *
1316 swabshort(u_char *sp, int n)
1317 {
1318 	char c;
1319 
1320 	while (--n >= 0) {
1321 		c = sp[0]; sp[0] = sp[1]; sp[1] = c;
1322 		sp += 2;
1323 	}
1324 	return (sp);
1325 }
1326 
1327 static u_char *
1328 swablong(u_char *sp, int n)
1329 {
1330 	char c;
1331 
1332 	while (--n >= 0) {
1333 		c = sp[0]; sp[0] = sp[3]; sp[3] = c;
1334 		c = sp[2]; sp[2] = sp[1]; sp[1] = c;
1335 		sp += 4;
1336 	}
1337 	return (sp);
1338 }
1339 
1340 void
1341 swabst(u_char *cp, u_char *sp)
1342 {
1343 	int n = 0;
1344 
1345 	while (*cp) {
1346 		switch (*cp) {
1347 		case '0': case '1': case '2': case '3': case '4':
1348 		case '5': case '6': case '7': case '8': case '9':
1349 			n = (n * 10) + (*cp++ - '0');
1350 			continue;
1351 
1352 		case 's': case 'w': case 'h':
1353 			if (n == 0)
1354 				n = 1;
1355 			sp = swabshort(sp, n);
1356 			break;
1357 
1358 		case 'l':
1359 			if (n == 0)
1360 				n = 1;
1361 			sp = swablong(sp, n);
1362 			break;
1363 
1364 		default: /* Any other character, like 'b' counts as byte. */
1365 			if (n == 0)
1366 				n = 1;
1367 			sp += n;
1368 			break;
1369 		}
1370 		cp++;
1371 		n = 0;
1372 	}
1373 }
1374 
1375 static u_long
1376 swabl(u_long x)
1377 {
1378 	swabst((u_char *)"l", (u_char *)&x);
1379 	return (x);
1380 }
1381