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