1/*-
2 * Copyright (c) 2002 Poul-Henning Kamp
3 * Copyright (c) 2002 Networks Associates Technology, Inc.
4 * All rights reserved.
5 *
6 * This software was developed for the FreeBSD Project by Poul-Henning Kamp
7 * and NAI Labs, the Security Research Division of Network Associates, Inc.
8 * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
9 * DARPA CHATS research program.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 *    notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 *    notice, this list of conditions and the following disclaimer in the
18 *    documentation and/or other materials provided with the distribution.
19 * 3. The names of the authors may not be used to endorse or promote
20 *    products derived from this software without specific prior written
21 *    permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 *
35 * Copyright (c) 1986, 1992, 1993
36 *	The Regents of the University of California.  All rights reserved.
37 *
38 * Redistribution and use in source and binary forms, with or without
39 * modification, are permitted provided that the following conditions
40 * are met:
41 * 1. Redistributions of source code must retain the above copyright
42 *    notice, this list of conditions and the following disclaimer.
43 * 2. Redistributions in binary form must reproduce the above copyright
44 *    notice, this list of conditions and the following disclaimer in the
45 *    documentation and/or other materials provided with the distribution.
46 * 4. Neither the name of the University nor the names of its contributors
47 *    may be used to endorse or promote products derived from this software
48 *    without specific prior written permission.
49 *
50 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
51 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
52 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
53 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
54 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
55 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
56 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
57 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
58 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
59 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
60 * SUCH DAMAGE.
61 */
62
63#include <sys/cdefs.h>
64__FBSDID("$FreeBSD: stable/10/sbin/savecore/savecore.c 321212 2017-07-19 16:38:55Z ngie $");
65
66#include <sys/param.h>
67#include <sys/disk.h>
68#include <sys/kerneldump.h>
69#include <sys/mount.h>
70#include <sys/stat.h>
71#include <ctype.h>
72#include <errno.h>
73#include <fcntl.h>
74#include <fstab.h>
75#include <paths.h>
76#include <signal.h>
77#include <stdarg.h>
78#include <stdio.h>
79#include <stdlib.h>
80#include <string.h>
81#include <syslog.h>
82#include <time.h>
83#include <unistd.h>
84
85/* The size of the buffer used for I/O. */
86#define	BUFFERSIZE	(1024*1024)
87
88#define	STATUS_BAD	0
89#define	STATUS_GOOD	1
90#define	STATUS_UNKNOWN	2
91
92static int checkfor, compress, clear, force, keep, verbose;	/* flags */
93static int nfound, nsaved, nerr;			/* statistics */
94static int maxdumps;
95
96extern FILE *zopen(const char *, const char *);
97
98static sig_atomic_t got_siginfo;
99static void infohandler(int);
100
101static void
102printheader(FILE *f, const struct kerneldumpheader *h, const char *device,
103    int bounds, const int status)
104{
105	uint64_t dumplen;
106	time_t t;
107	const char *stat_str;
108
109	fprintf(f, "Dump header from device %s\n", device);
110	fprintf(f, "  Architecture: %s\n", h->architecture);
111	fprintf(f, "  Architecture Version: %u\n",
112	    dtoh32(h->architectureversion));
113	dumplen = dtoh64(h->dumplength);
114	fprintf(f, "  Dump Length: %lldB (%lld MB)\n", (long long)dumplen,
115	    (long long)(dumplen >> 20));
116	fprintf(f, "  Blocksize: %d\n", dtoh32(h->blocksize));
117	t = dtoh64(h->dumptime);
118	fprintf(f, "  Dumptime: %s", ctime(&t));
119	fprintf(f, "  Hostname: %s\n", h->hostname);
120	fprintf(f, "  Magic: %s\n", h->magic);
121	fprintf(f, "  Version String: %s", h->versionstring);
122	fprintf(f, "  Panic String: %s\n", h->panicstring);
123	fprintf(f, "  Dump Parity: %u\n", h->parity);
124	fprintf(f, "  Bounds: %d\n", bounds);
125
126	switch(status) {
127	case STATUS_BAD:
128		stat_str = "bad";
129		break;
130	case STATUS_GOOD:
131		stat_str = "good";
132		break;
133	default:
134		stat_str = "unknown";
135	}
136	fprintf(f, "  Dump Status: %s\n", stat_str);
137	fflush(f);
138}
139
140static int
141getbounds(void) {
142	FILE *fp;
143	char buf[6];
144	int ret;
145
146	ret = 0;
147
148	if ((fp = fopen("bounds", "r")) == NULL) {
149		if (verbose)
150			printf("unable to open bounds file, using 0\n");
151		return (ret);
152	}
153
154	if (fgets(buf, sizeof buf, fp) == NULL) {
155		if (feof(fp))
156			syslog(LOG_WARNING, "bounds file is empty, using 0");
157		else
158			syslog(LOG_WARNING, "bounds file: %s", strerror(errno));
159		fclose(fp);
160		return (ret);
161	}
162
163	errno = 0;
164	ret = (int)strtol(buf, NULL, 10);
165	if (ret == 0 && (errno == EINVAL || errno == ERANGE))
166		syslog(LOG_WARNING, "invalid value found in bounds, using 0");
167	fclose(fp);
168	return (ret);
169}
170
171static void
172writebounds(int bounds) {
173	FILE *fp;
174
175	if ((fp = fopen("bounds", "w")) == NULL) {
176		syslog(LOG_WARNING, "unable to write to bounds file: %m");
177		return;
178	}
179
180	if (verbose)
181		printf("bounds number: %d\n", bounds);
182
183	fprintf(fp, "%d\n", bounds);
184	fclose(fp);
185}
186
187static off_t
188file_size(const char *path)
189{
190	struct stat sb;
191
192	/* Ignore all errors, those file may not exists. */
193	if (stat(path, &sb) == -1)
194		return (0);
195	return (sb.st_size);
196}
197
198static off_t
199saved_dump_size(int bounds)
200{
201	static char path[PATH_MAX];
202	off_t dumpsize;
203
204	dumpsize = 0;
205
206	(void)snprintf(path, sizeof(path), "info.%d", bounds);
207	dumpsize += file_size(path);
208	(void)snprintf(path, sizeof(path), "vmcore.%d", bounds);
209	dumpsize += file_size(path);
210	(void)snprintf(path, sizeof(path), "vmcore.%d.gz", bounds);
211	dumpsize += file_size(path);
212	(void)snprintf(path, sizeof(path), "textdump.tar.%d", bounds);
213	dumpsize += file_size(path);
214	(void)snprintf(path, sizeof(path), "textdump.tar.%d.gz", bounds);
215	dumpsize += file_size(path);
216
217	return (dumpsize);
218}
219
220static void
221saved_dump_remove(int bounds)
222{
223	static char path[PATH_MAX];
224
225	(void)snprintf(path, sizeof(path), "info.%d", bounds);
226	(void)unlink(path);
227	(void)snprintf(path, sizeof(path), "vmcore.%d", bounds);
228	(void)unlink(path);
229	(void)snprintf(path, sizeof(path), "vmcore.%d.gz", bounds);
230	(void)unlink(path);
231	(void)snprintf(path, sizeof(path), "textdump.tar.%d", bounds);
232	(void)unlink(path);
233	(void)snprintf(path, sizeof(path), "textdump.tar.%d.gz", bounds);
234	(void)unlink(path);
235}
236
237static void
238symlinks_remove(void)
239{
240
241	(void)unlink("info.last");
242	(void)unlink("vmcore.last");
243	(void)unlink("vmcore.last.gz");
244	(void)unlink("textdump.tar.last");
245	(void)unlink("textdump.tar.last.gz");
246}
247
248/*
249 * Check that sufficient space is available on the disk that holds the
250 * save directory.
251 */
252static int
253check_space(const char *savedir, off_t dumpsize, int bounds)
254{
255	FILE *fp;
256	off_t available, minfree, spacefree, totfree, needed;
257	struct statfs fsbuf;
258	char buf[100];
259
260	if (statfs(".", &fsbuf) < 0) {
261		syslog(LOG_ERR, "%s: %m", savedir);
262		exit(1);
263	}
264	spacefree = ((off_t) fsbuf.f_bavail * fsbuf.f_bsize) / 1024;
265	totfree = ((off_t) fsbuf.f_bfree * fsbuf.f_bsize) / 1024;
266
267	if ((fp = fopen("minfree", "r")) == NULL)
268		minfree = 0;
269	else {
270		if (fgets(buf, sizeof(buf), fp) == NULL)
271			minfree = 0;
272		else {
273			char *endp;
274
275			errno = 0;
276			minfree = strtoll(buf, &endp, 10);
277			if (minfree == 0 && errno != 0)
278				minfree = -1;
279			else {
280				while (*endp != '\0' && isspace(*endp))
281					endp++;
282				if (*endp != '\0' || minfree < 0)
283					minfree = -1;
284			}
285			if (minfree < 0)
286				syslog(LOG_WARNING,
287				    "`minfree` didn't contain a valid size "
288				    "(`%s`). Defaulting to 0", buf);
289		}
290		(void)fclose(fp);
291	}
292
293	available = minfree > 0 ? spacefree - minfree : totfree;
294	needed = dumpsize / 1024 + 2;	/* 2 for info file */
295	needed -= saved_dump_size(bounds);
296	if (available < needed) {
297		syslog(LOG_WARNING,
298		    "no dump: not enough free space on device (need at least "
299		    "%jdkB for dump; %jdkB available; %jdkB reserved)",
300		    (intmax_t)needed,
301		    (intmax_t)available + minfree,
302		    (intmax_t)minfree);
303		return (0);
304	}
305	if (spacefree - needed < 0)
306		syslog(LOG_WARNING,
307		    "dump performed, but free space threshold crossed");
308	return (1);
309}
310
311#define BLOCKSIZE (1<<12)
312#define BLOCKMASK (~(BLOCKSIZE-1))
313
314static int
315DoRegularFile(int fd, off_t dumpsize, char *buf, const char *device,
316    const char *filename, FILE *fp)
317{
318	int he, hs, nr, nw, wl;
319	off_t dmpcnt, origsize;
320
321	dmpcnt = 0;
322	origsize = dumpsize;
323	he = 0;
324	while (dumpsize > 0) {
325		wl = BUFFERSIZE;
326		if (wl > dumpsize)
327			wl = dumpsize;
328		nr = read(fd, buf, wl);
329		if (nr != wl) {
330			if (nr == 0)
331				syslog(LOG_WARNING,
332				    "WARNING: EOF on dump device");
333			else
334				syslog(LOG_ERR, "read error on %s: %m", device);
335			nerr++;
336			return (-1);
337		}
338		if (compress) {
339			nw = fwrite(buf, 1, wl, fp);
340		} else {
341			for (nw = 0; nw < nr; nw = he) {
342				/* find a contiguous block of zeroes */
343				for (hs = nw; hs < nr; hs += BLOCKSIZE) {
344					for (he = hs; he < nr && buf[he] == 0;
345					    ++he)
346						/* nothing */ ;
347					/* is the hole long enough to matter? */
348					if (he >= hs + BLOCKSIZE)
349						break;
350				}
351
352				/* back down to a block boundary */
353				he &= BLOCKMASK;
354
355				/*
356				 * 1) Don't go beyond the end of the buffer.
357				 * 2) If the end of the buffer is less than
358				 *    BLOCKSIZE bytes away, we're at the end
359				 *    of the file, so just grab what's left.
360				 */
361				if (hs + BLOCKSIZE > nr)
362					hs = he = nr;
363
364				/*
365				 * At this point, we have a partial ordering:
366				 *     nw <= hs <= he <= nr
367				 * If hs > nw, buf[nw..hs] contains non-zero data.
368				 * If he > hs, buf[hs..he] is all zeroes.
369				 */
370				if (hs > nw)
371					if (fwrite(buf + nw, hs - nw, 1, fp)
372					    != 1)
373					break;
374				if (he > hs)
375					if (fseeko(fp, he - hs, SEEK_CUR) == -1)
376						break;
377			}
378		}
379		if (nw != wl) {
380			syslog(LOG_ERR,
381			    "write error on %s file: %m", filename);
382			syslog(LOG_WARNING,
383			    "WARNING: vmcore may be incomplete");
384			nerr++;
385			return (-1);
386		}
387		if (verbose) {
388			dmpcnt += wl;
389			printf("%llu\r", (unsigned long long)dmpcnt);
390			fflush(stdout);
391		}
392		dumpsize -= wl;
393		if (got_siginfo) {
394			printf("%s %.1lf%%\n", filename, (100.0 - (100.0 *
395			    (double)dumpsize / (double)origsize)));
396			got_siginfo = 0;
397		}
398	}
399	return (0);
400}
401
402/*
403 * Specialized version of dump-reading logic for use with textdumps, which
404 * are written backwards from the end of the partition, and must be reversed
405 * before being written to the file.  Textdumps are small, so do a bit less
406 * work to optimize/sparsify.
407 */
408static int
409DoTextdumpFile(int fd, off_t dumpsize, off_t lasthd, char *buf,
410    const char *device, const char *filename, FILE *fp)
411{
412	int nr, nw, wl;
413	off_t dmpcnt, totsize;
414
415	totsize = dumpsize;
416	dmpcnt = 0;
417	wl = 512;
418	if ((dumpsize % wl) != 0) {
419		syslog(LOG_ERR, "textdump uneven multiple of 512 on %s",
420		    device);
421		nerr++;
422		return (-1);
423	}
424	while (dumpsize > 0) {
425		nr = pread(fd, buf, wl, lasthd - (totsize - dumpsize) - wl);
426		if (nr != wl) {
427			if (nr == 0)
428				syslog(LOG_WARNING,
429				    "WARNING: EOF on dump device");
430			else
431				syslog(LOG_ERR, "read error on %s: %m", device);
432			nerr++;
433			return (-1);
434		}
435		nw = fwrite(buf, 1, wl, fp);
436		if (nw != wl) {
437			syslog(LOG_ERR,
438			    "write error on %s file: %m", filename);
439			syslog(LOG_WARNING,
440			    "WARNING: textdump may be incomplete");
441			nerr++;
442			return (-1);
443		}
444		if (verbose) {
445			dmpcnt += wl;
446			printf("%llu\r", (unsigned long long)dmpcnt);
447			fflush(stdout);
448		}
449		dumpsize -= wl;
450	}
451	return (0);
452}
453
454static void
455DoFile(const char *savedir, const char *device)
456{
457	static char infoname[PATH_MAX], corename[PATH_MAX], linkname[PATH_MAX];
458	static char *buf = NULL;
459	struct kerneldumpheader kdhf, kdhl;
460	off_t mediasize, dumpsize, firsthd, lasthd;
461	FILE *info, *fp;
462	mode_t oumask;
463	int fd, fdinfo, error;
464	int bounds, status;
465	u_int sectorsize;
466	int istextdump;
467
468	bounds = getbounds();
469	mediasize = 0;
470	status = STATUS_UNKNOWN;
471
472	if (maxdumps > 0 && bounds == maxdumps)
473		bounds = 0;
474
475	if (buf == NULL) {
476		buf = malloc(BUFFERSIZE);
477		if (buf == NULL) {
478			syslog(LOG_ERR, "%m");
479			return;
480		}
481	}
482
483	if (verbose)
484		printf("checking for kernel dump on device %s\n", device);
485
486	fd = open(device, (checkfor || keep) ? O_RDONLY : O_RDWR);
487	if (fd < 0) {
488		syslog(LOG_ERR, "%s: %m", device);
489		return;
490	}
491
492	error = ioctl(fd, DIOCGMEDIASIZE, &mediasize);
493	if (!error)
494		error = ioctl(fd, DIOCGSECTORSIZE, &sectorsize);
495	if (error) {
496		syslog(LOG_ERR,
497		    "couldn't find media and/or sector size of %s: %m", device);
498		goto closefd;
499	}
500
501	if (verbose) {
502		printf("mediasize = %lld bytes\n", (long long)mediasize);
503		printf("sectorsize = %u bytes\n", sectorsize);
504	}
505
506	lasthd = mediasize - sectorsize;
507	lseek(fd, lasthd, SEEK_SET);
508	error = read(fd, &kdhl, sizeof kdhl);
509	if (error != sizeof kdhl) {
510		syslog(LOG_ERR,
511		    "error reading last dump header at offset %lld in %s: %m",
512		    (long long)lasthd, device);
513		goto closefd;
514	}
515	istextdump = 0;
516	if (strncmp(kdhl.magic, TEXTDUMPMAGIC, sizeof kdhl) == 0) {
517		if (verbose)
518			printf("textdump magic on last dump header on %s\n",
519			    device);
520		istextdump = 1;
521		if (dtoh32(kdhl.version) != KERNELDUMP_TEXT_VERSION) {
522			syslog(LOG_ERR,
523			    "unknown version (%d) in last dump header on %s",
524			    dtoh32(kdhl.version), device);
525
526			status = STATUS_BAD;
527			if (force == 0)
528				goto closefd;
529		}
530	} else if (memcmp(kdhl.magic, KERNELDUMPMAGIC, sizeof kdhl.magic) ==
531	    0) {
532		if (dtoh32(kdhl.version) != KERNELDUMPVERSION) {
533			syslog(LOG_ERR,
534			    "unknown version (%d) in last dump header on %s",
535			    dtoh32(kdhl.version), device);
536
537			status = STATUS_BAD;
538			if (force == 0)
539				goto closefd;
540		}
541	} else {
542		if (verbose)
543			printf("magic mismatch on last dump header on %s\n",
544			    device);
545
546		status = STATUS_BAD;
547		if (force == 0)
548			goto closefd;
549
550		if (memcmp(kdhl.magic, KERNELDUMPMAGIC_CLEARED,
551			    sizeof kdhl.magic) == 0) {
552			if (verbose)
553				printf("forcing magic on %s\n", device);
554			memcpy(kdhl.magic, KERNELDUMPMAGIC,
555			    sizeof kdhl.magic);
556		} else {
557			syslog(LOG_ERR, "unable to force dump - bad magic");
558			goto closefd;
559		}
560		if (dtoh32(kdhl.version) != KERNELDUMPVERSION) {
561			syslog(LOG_ERR,
562			    "unknown version (%d) in last dump header on %s",
563			    dtoh32(kdhl.version), device);
564
565			status = STATUS_BAD;
566			if (force == 0)
567				goto closefd;
568		}
569	}
570
571	nfound++;
572	if (clear)
573		goto nuke;
574
575	if (kerneldump_parity(&kdhl)) {
576		syslog(LOG_ERR,
577		    "parity error on last dump header on %s", device);
578		nerr++;
579		status = STATUS_BAD;
580		if (force == 0)
581			goto closefd;
582	}
583	dumpsize = dtoh64(kdhl.dumplength);
584	firsthd = lasthd - dumpsize - sizeof kdhf;
585	lseek(fd, firsthd, SEEK_SET);
586	error = read(fd, &kdhf, sizeof kdhf);
587	if (error != sizeof kdhf) {
588		syslog(LOG_ERR,
589		    "error reading first dump header at offset %lld in %s: %m",
590		    (long long)firsthd, device);
591		nerr++;
592		goto closefd;
593	}
594
595	if (verbose >= 2) {
596		printf("First dump headers:\n");
597		printheader(stdout, &kdhf, device, bounds, -1);
598
599		printf("\nLast dump headers:\n");
600		printheader(stdout, &kdhl, device, bounds, -1);
601		printf("\n");
602	}
603
604	if (memcmp(&kdhl, &kdhf, sizeof kdhl)) {
605		syslog(LOG_ERR,
606		    "first and last dump headers disagree on %s", device);
607		nerr++;
608		status = STATUS_BAD;
609		if (force == 0)
610			goto closefd;
611	} else {
612		status = STATUS_GOOD;
613	}
614
615	if (checkfor) {
616		printf("A dump exists on %s\n", device);
617		close(fd);
618		exit(0);
619	}
620
621	if (kdhl.panicstring[0])
622		syslog(LOG_ALERT, "reboot after panic: %s", kdhl.panicstring);
623	else
624		syslog(LOG_ALERT, "reboot");
625
626	if (verbose)
627		printf("Checking for available free space\n");
628
629	if (!check_space(savedir, dumpsize, bounds)) {
630		nerr++;
631		goto closefd;
632	}
633
634	writebounds(bounds + 1);
635
636	saved_dump_remove(bounds);
637
638	snprintf(infoname, sizeof(infoname), "info.%d", bounds);
639
640	/*
641	 * Create or overwrite any existing dump header files.
642	 */
643	fdinfo = open(infoname, O_WRONLY | O_CREAT | O_TRUNC, 0600);
644	if (fdinfo < 0) {
645		syslog(LOG_ERR, "%s: %m", infoname);
646		nerr++;
647		goto closefd;
648	}
649	oumask = umask(S_IRWXG|S_IRWXO); /* Restrict access to the core file.*/
650	if (compress) {
651		snprintf(corename, sizeof(corename), "%s.%d.gz",
652		    istextdump ? "textdump.tar" : "vmcore", bounds);
653		fp = zopen(corename, "w");
654	} else {
655		snprintf(corename, sizeof(corename), "%s.%d",
656		    istextdump ? "textdump.tar" : "vmcore", bounds);
657		fp = fopen(corename, "w");
658	}
659	if (fp == NULL) {
660		syslog(LOG_ERR, "%s: %m", corename);
661		close(fdinfo);
662		nerr++;
663		goto closefd;
664	}
665	(void)umask(oumask);
666
667	info = fdopen(fdinfo, "w");
668
669	if (info == NULL) {
670		syslog(LOG_ERR, "fdopen failed: %m");
671		nerr++;
672		goto closefd;
673	}
674
675	if (verbose)
676		printheader(stdout, &kdhl, device, bounds, status);
677
678	printheader(info, &kdhl, device, bounds, status);
679	fclose(info);
680
681	syslog(LOG_NOTICE, "writing %score to %s/%s",
682	    compress ? "compressed " : "", savedir, corename);
683
684	if (istextdump) {
685		if (DoTextdumpFile(fd, dumpsize, lasthd, buf, device,
686		    corename, fp) < 0)
687			goto closeall;
688	} else {
689		if (DoRegularFile(fd, dumpsize, buf, device, corename, fp)
690		    < 0)
691			goto closeall;
692	}
693	if (verbose)
694		printf("\n");
695
696	if (fclose(fp) < 0) {
697		syslog(LOG_ERR, "error on %s: %m", corename);
698		nerr++;
699		goto closefd;
700	}
701
702	symlinks_remove();
703	if (symlink(infoname, "info.last") == -1) {
704		syslog(LOG_WARNING, "unable to create symlink %s/%s: %m",
705		    savedir, "info.last");
706	}
707	if (compress) {
708		snprintf(linkname, sizeof(linkname), "%s.last.gz",
709		    istextdump ? "textdump.tar" : "vmcore");
710	} else {
711		snprintf(linkname, sizeof(linkname), "%s.last",
712		    istextdump ? "textdump.tar" : "vmcore");
713	}
714	if (symlink(corename, linkname) == -1) {
715		syslog(LOG_WARNING, "unable to create symlink %s/%s: %m",
716		    savedir, linkname);
717	}
718
719	nsaved++;
720
721	if (verbose)
722		printf("dump saved\n");
723
724nuke:
725	if (!keep) {
726		if (verbose)
727			printf("clearing dump header\n");
728		memcpy(kdhl.magic, KERNELDUMPMAGIC_CLEARED, sizeof kdhl.magic);
729		lseek(fd, lasthd, SEEK_SET);
730		error = write(fd, &kdhl, sizeof kdhl);
731		if (error != sizeof kdhl)
732			syslog(LOG_ERR,
733			    "error while clearing the dump header: %m");
734	}
735	close(fd);
736	return;
737
738closeall:
739	fclose(fp);
740
741closefd:
742	close(fd);
743}
744
745static void
746usage(void)
747{
748	fprintf(stderr, "%s\n%s\n%s\n",
749	    "usage: savecore -c [-v] [device ...]",
750	    "       savecore -C [-v] [device ...]",
751	    "       savecore [-fkvz] [-m maxdumps] [directory [device ...]]");
752	exit(1);
753}
754
755int
756main(int argc, char **argv)
757{
758	const char *savedir = ".";
759	struct fstab *fsp;
760	int i, ch, error;
761
762	checkfor = compress = clear = force = keep = verbose = 0;
763	nfound = nsaved = nerr = 0;
764
765	openlog("savecore", LOG_PERROR, LOG_DAEMON);
766	signal(SIGINFO, infohandler);
767
768	while ((ch = getopt(argc, argv, "Ccfkm:vz")) != -1)
769		switch(ch) {
770		case 'C':
771			checkfor = 1;
772			break;
773		case 'c':
774			clear = 1;
775			break;
776		case 'f':
777			force = 1;
778			break;
779		case 'k':
780			keep = 1;
781			break;
782		case 'm':
783			maxdumps = atoi(optarg);
784			if (maxdumps <= 0) {
785				syslog(LOG_ERR, "Invalid maxdump value");
786				exit(1);
787			}
788			break;
789		case 'v':
790			verbose++;
791			break;
792		case 'z':
793			compress = 1;
794			break;
795		case '?':
796		default:
797			usage();
798		}
799	if (checkfor && (clear || force || keep))
800		usage();
801	if (clear && (compress || keep))
802		usage();
803	if (maxdumps > 0 && (checkfor || clear))
804		usage();
805	argc -= optind;
806	argv += optind;
807	if (argc >= 1 && !checkfor && !clear) {
808		error = chdir(argv[0]);
809		if (error) {
810			syslog(LOG_ERR, "chdir(%s): %m", argv[0]);
811			exit(1);
812		}
813		savedir = argv[0];
814		argc--;
815		argv++;
816	}
817	if (argc == 0) {
818		for (;;) {
819			fsp = getfsent();
820			if (fsp == NULL)
821				break;
822			if (strcmp(fsp->fs_vfstype, "swap") &&
823			    strcmp(fsp->fs_vfstype, "dump"))
824				continue;
825			DoFile(savedir, fsp->fs_spec);
826		}
827	} else {
828		for (i = 0; i < argc; i++)
829			DoFile(savedir, argv[i]);
830	}
831
832	/* Emit minimal output. */
833	if (nfound == 0) {
834		if (checkfor) {
835			printf("No dump exists\n");
836			exit(1);
837		}
838		syslog(LOG_WARNING, "no dumps found");
839	}
840	else if (nsaved == 0) {
841		if (nerr != 0)
842			syslog(LOG_WARNING, "unsaved dumps found but not saved");
843		else
844			syslog(LOG_WARNING, "no unsaved dumps found");
845	}
846
847	return (0);
848}
849
850static void
851infohandler(int sig __unused)
852{
853	got_siginfo = 1;
854}
855