savecore.c revision 331722 
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/11/sbin/savecore/savecore.c 331722 2018-03-29 02:50:57Z eadler $");
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 <stdbool.h>
79#include <stdio.h>
80#include <stdlib.h>
81#include <string.h>
82#include <syslog.h>
83#include <time.h>
84#include <unistd.h>
85#include <libxo/xo.h>
86
87/* The size of the buffer used for I/O. */
88#define	BUFFERSIZE	(1024*1024)
89
90#define	STATUS_BAD	0
91#define	STATUS_GOOD	1
92#define	STATUS_UNKNOWN	2
93
94static int checkfor, compress, clear, force, keep, verbose;	/* flags */
95static int nfound, nsaved, nerr;			/* statistics */
96static int maxdumps;
97
98extern FILE *zopen(const char *, const char *);
99
100static sig_atomic_t got_siginfo;
101static void infohandler(int);
102
103static void
104printheader(xo_handle_t *xo, const struct kerneldumpheader *h,
105    const char *device, int bounds, const int status)
106{
107	uint64_t dumplen;
108	time_t t;
109	const char *stat_str;
110
111	xo_flush_h(xo);
112	xo_emit_h(xo, "{Lwc:Dump header from device}{:dump_device/%s}\n",
113	    device);
114	xo_emit_h(xo, "{P:  }{Lwc:Architecture}{:architecture/%s}\n",
115	    h->architecture);
116	xo_emit_h(xo,
117	    "{P:  }{Lwc:Architecture Version}{:architecture_version/%u}\n",
118	    dtoh32(h->architectureversion));
119	dumplen = dtoh64(h->dumplength);
120	xo_emit_h(xo, "{P:  }{Lwc:Dump Length}{:dump_length_bytes/%lld}\n",
121	    (long long)dumplen);
122	xo_emit_h(xo, "{P:  }{Lwc:Blocksize}{:blocksize/%d}\n",
123	    dtoh32(h->blocksize));
124
125	t = dtoh64(h->dumptime);
126	xo_emit_h(xo, "{P:  }{Lwc:Dumptime}{:dumptime/%s}", ctime(&t));
127	xo_emit_h(xo, "{P:  }{Lwc:Hostname}{:hostname/%s}\n", h->hostname);
128	xo_emit_h(xo, "{P:  }{Lwc:Magic}{:magic/%s}\n", h->magic);
129	xo_emit_h(xo, "{P:  }{Lwc:Version String}{:version_string/%s}",
130	    h->versionstring);
131	xo_emit_h(xo, "{P:  }{Lwc:Panic String}{:panic_string/%s}\n",
132	    h->panicstring);
133	xo_emit_h(xo, "{P:  }{Lwc:Dump Parity}{:dump_parity/%u}\n", h->parity);
134	xo_emit_h(xo, "{P:  }{Lwc:Bounds}{:bounds/%d}\n", bounds);
135
136	switch (status) {
137	case STATUS_BAD:
138		stat_str = "bad";
139		break;
140	case STATUS_GOOD:
141		stat_str = "good";
142		break;
143	default:
144		stat_str = "unknown";
145		break;
146	}
147	xo_emit_h(xo, "{P:  }{Lwc:Dump Status}{:dump_status/%s}\n", stat_str);
148	xo_flush_h(xo);
149}
150
151static int
152getbounds(void)
153{
154	FILE *fp;
155	char buf[6];
156	int ret;
157
158	/*
159	 * If we are just checking, then we haven't done a chdir to the dump
160	 * directory and we should not try to read a bounds file.
161	 */
162	if (checkfor)
163		return (0);
164
165	ret = 0;
166
167	if ((fp = fopen("bounds", "r")) == NULL) {
168		if (verbose)
169			printf("unable to open bounds file, using 0\n");
170		return (ret);
171	}
172
173	if (fgets(buf, sizeof buf, fp) == NULL) {
174		if (feof(fp))
175			syslog(LOG_WARNING, "bounds file is empty, using 0");
176		else
177			syslog(LOG_WARNING, "bounds file: %s", strerror(errno));
178		fclose(fp);
179		return (ret);
180	}
181
182	errno = 0;
183	ret = (int)strtol(buf, NULL, 10);
184	if (ret == 0 && (errno == EINVAL || errno == ERANGE))
185		syslog(LOG_WARNING, "invalid value found in bounds, using 0");
186	fclose(fp);
187	return (ret);
188}
189
190static void
191writebounds(int bounds)
192{
193	FILE *fp;
194
195	if ((fp = fopen("bounds", "w")) == NULL) {
196		syslog(LOG_WARNING, "unable to write to bounds file: %m");
197		return;
198	}
199
200	if (verbose)
201		printf("bounds number: %d\n", bounds);
202
203	fprintf(fp, "%d\n", bounds);
204	fclose(fp);
205}
206
207static off_t
208file_size(const char *path)
209{
210	struct stat sb;
211
212	/* Ignore all errors, those file may not exists. */
213	if (stat(path, &sb) == -1)
214		return (0);
215	return (sb.st_size);
216}
217
218static off_t
219saved_dump_size(int bounds)
220{
221	static char path[PATH_MAX];
222	off_t dumpsize;
223
224	dumpsize = 0;
225
226	(void)snprintf(path, sizeof(path), "info.%d", bounds);
227	dumpsize += file_size(path);
228	(void)snprintf(path, sizeof(path), "vmcore.%d", bounds);
229	dumpsize += file_size(path);
230	(void)snprintf(path, sizeof(path), "vmcore.%d.gz", bounds);
231	dumpsize += file_size(path);
232	(void)snprintf(path, sizeof(path), "textdump.tar.%d", bounds);
233	dumpsize += file_size(path);
234	(void)snprintf(path, sizeof(path), "textdump.tar.%d.gz", bounds);
235	dumpsize += file_size(path);
236
237	return (dumpsize);
238}
239
240static void
241saved_dump_remove(int bounds)
242{
243	static char path[PATH_MAX];
244
245	(void)snprintf(path, sizeof(path), "info.%d", bounds);
246	(void)unlink(path);
247	(void)snprintf(path, sizeof(path), "vmcore.%d", bounds);
248	(void)unlink(path);
249	(void)snprintf(path, sizeof(path), "vmcore.%d.gz", bounds);
250	(void)unlink(path);
251	(void)snprintf(path, sizeof(path), "textdump.tar.%d", bounds);
252	(void)unlink(path);
253	(void)snprintf(path, sizeof(path), "textdump.tar.%d.gz", bounds);
254	(void)unlink(path);
255}
256
257static void
258symlinks_remove(void)
259{
260
261	(void)unlink("info.last");
262	(void)unlink("vmcore.last");
263	(void)unlink("vmcore.last.gz");
264	(void)unlink("textdump.tar.last");
265	(void)unlink("textdump.tar.last.gz");
266}
267
268/*
269 * Check that sufficient space is available on the disk that holds the
270 * save directory.
271 */
272static int
273check_space(const char *savedir, off_t dumpsize, int bounds)
274{
275	FILE *fp;
276	off_t available, minfree, spacefree, totfree, needed;
277	struct statfs fsbuf;
278	char buf[100];
279
280	if (statfs(".", &fsbuf) < 0) {
281		syslog(LOG_ERR, "%s: %m", savedir);
282		exit(1);
283	}
284	spacefree = ((off_t) fsbuf.f_bavail * fsbuf.f_bsize) / 1024;
285	totfree = ((off_t) fsbuf.f_bfree * fsbuf.f_bsize) / 1024;
286
287	if ((fp = fopen("minfree", "r")) == NULL)
288		minfree = 0;
289	else {
290		if (fgets(buf, sizeof(buf), fp) == NULL)
291			minfree = 0;
292		else {
293			char *endp;
294
295			errno = 0;
296			minfree = strtoll(buf, &endp, 10);
297			if (minfree == 0 && errno != 0)
298				minfree = -1;
299			else {
300				while (*endp != '\0' && isspace(*endp))
301					endp++;
302				if (*endp != '\0' || minfree < 0)
303					minfree = -1;
304			}
305			if (minfree < 0)
306				syslog(LOG_WARNING,
307				    "`minfree` didn't contain a valid size "
308				    "(`%s`). Defaulting to 0", buf);
309		}
310		(void)fclose(fp);
311	}
312
313	available = minfree > 0 ? spacefree - minfree : totfree;
314	needed = dumpsize / 1024 + 2;	/* 2 for info file */
315	needed -= saved_dump_size(bounds);
316	if (available < needed) {
317		syslog(LOG_WARNING,
318		    "no dump: not enough free space on device (need at least "
319		    "%jdkB for dump; %jdkB available; %jdkB reserved)",
320		    (intmax_t)needed,
321		    (intmax_t)available + minfree,
322		    (intmax_t)minfree);
323		return (0);
324	}
325	if (spacefree - needed < 0)
326		syslog(LOG_WARNING,
327		    "dump performed, but free space threshold crossed");
328	return (1);
329}
330
331static bool
332compare_magic(const struct kerneldumpheader *kdh, const char *magic)
333{
334
335	return (strncmp(kdh->magic, magic, sizeof(kdh->magic)) == 0);
336}
337
338#define BLOCKSIZE (1<<12)
339#define BLOCKMASK (~(BLOCKSIZE-1))
340
341static int
342DoRegularFile(int fd, off_t dumpsize, char *buf, const char *device,
343    const char *filename, FILE *fp)
344{
345	int he, hs, nr, nw, wl;
346	off_t dmpcnt, origsize;
347
348	dmpcnt = 0;
349	origsize = dumpsize;
350	he = 0;
351	while (dumpsize > 0) {
352		wl = BUFFERSIZE;
353		if (wl > dumpsize)
354			wl = dumpsize;
355		nr = read(fd, buf, wl);
356		if (nr != wl) {
357			if (nr == 0)
358				syslog(LOG_WARNING,
359				    "WARNING: EOF on dump device");
360			else
361				syslog(LOG_ERR, "read error on %s: %m", device);
362			nerr++;
363			return (-1);
364		}
365		if (compress) {
366			nw = fwrite(buf, 1, wl, fp);
367		} else {
368			for (nw = 0; nw < nr; nw = he) {
369				/* find a contiguous block of zeroes */
370				for (hs = nw; hs < nr; hs += BLOCKSIZE) {
371					for (he = hs; he < nr && buf[he] == 0;
372					    ++he)
373						/* nothing */ ;
374					/* is the hole long enough to matter? */
375					if (he >= hs + BLOCKSIZE)
376						break;
377				}
378
379				/* back down to a block boundary */
380				he &= BLOCKMASK;
381
382				/*
383				 * 1) Don't go beyond the end of the buffer.
384				 * 2) If the end of the buffer is less than
385				 *    BLOCKSIZE bytes away, we're at the end
386				 *    of the file, so just grab what's left.
387				 */
388				if (hs + BLOCKSIZE > nr)
389					hs = he = nr;
390
391				/*
392				 * At this point, we have a partial ordering:
393				 *     nw <= hs <= he <= nr
394				 * If hs > nw, buf[nw..hs] contains non-zero
395				 * data. If he > hs, buf[hs..he] is all zeroes.
396				 */
397				if (hs > nw)
398					if (fwrite(buf + nw, hs - nw, 1, fp)
399					    != 1)
400					break;
401				if (he > hs)
402					if (fseeko(fp, he - hs, SEEK_CUR) == -1)
403						break;
404			}
405		}
406		if (nw != wl) {
407			syslog(LOG_ERR,
408			    "write error on %s file: %m", filename);
409			syslog(LOG_WARNING,
410			    "WARNING: vmcore may be incomplete");
411			nerr++;
412			return (-1);
413		}
414		if (verbose) {
415			dmpcnt += wl;
416			printf("%llu\r", (unsigned long long)dmpcnt);
417			fflush(stdout);
418		}
419		dumpsize -= wl;
420		if (got_siginfo) {
421			printf("%s %.1lf%%\n", filename, (100.0 - (100.0 *
422			    (double)dumpsize / (double)origsize)));
423			got_siginfo = 0;
424		}
425	}
426	return (0);
427}
428
429/*
430 * Specialized version of dump-reading logic for use with textdumps, which
431 * are written backwards from the end of the partition, and must be reversed
432 * before being written to the file.  Textdumps are small, so do a bit less
433 * work to optimize/sparsify.
434 */
435static int
436DoTextdumpFile(int fd, off_t dumpsize, off_t lasthd, char *buf,
437    const char *device, const char *filename, FILE *fp)
438{
439	int nr, nw, wl;
440	off_t dmpcnt, totsize;
441
442	totsize = dumpsize;
443	dmpcnt = 0;
444	wl = 512;
445	if ((dumpsize % wl) != 0) {
446		syslog(LOG_ERR, "textdump uneven multiple of 512 on %s",
447		    device);
448		nerr++;
449		return (-1);
450	}
451	while (dumpsize > 0) {
452		nr = pread(fd, buf, wl, lasthd - (totsize - dumpsize) - wl);
453		if (nr != wl) {
454			if (nr == 0)
455				syslog(LOG_WARNING,
456				    "WARNING: EOF on dump device");
457			else
458				syslog(LOG_ERR, "read error on %s: %m", device);
459			nerr++;
460			return (-1);
461		}
462		nw = fwrite(buf, 1, wl, fp);
463		if (nw != wl) {
464			syslog(LOG_ERR,
465			    "write error on %s file: %m", filename);
466			syslog(LOG_WARNING,
467			    "WARNING: textdump may be incomplete");
468			nerr++;
469			return (-1);
470		}
471		if (verbose) {
472			dmpcnt += wl;
473			printf("%llu\r", (unsigned long long)dmpcnt);
474			fflush(stdout);
475		}
476		dumpsize -= wl;
477	}
478	return (0);
479}
480
481static void
482DoFile(const char *savedir, const char *device)
483{
484	xo_handle_t *xostdout, *xoinfo;
485	static char infoname[PATH_MAX], corename[PATH_MAX], linkname[PATH_MAX];
486	static char *buf = NULL, *temp = NULL;
487	struct kerneldumpheader kdhf, kdhl;
488	off_t mediasize, dumpsize, firsthd, lasthd;
489	FILE *info, *fp;
490	mode_t oumask;
491	int fd, fdinfo, error;
492	int bounds, status;
493	u_int sectorsize, xostyle;
494	int istextdump;
495
496	bounds = getbounds();
497	mediasize = 0;
498	status = STATUS_UNKNOWN;
499
500	xostdout = xo_create_to_file(stdout, XO_STYLE_TEXT, 0);
501	if (xostdout == NULL) {
502		syslog(LOG_ERR, "%s: %m", infoname);
503		return;
504	}
505
506	if (maxdumps > 0 && bounds == maxdumps)
507		bounds = 0;
508
509	if (buf == NULL) {
510		buf = malloc(BUFFERSIZE);
511		if (buf == NULL) {
512			syslog(LOG_ERR, "%m");
513			return;
514		}
515	}
516
517	if (verbose)
518		printf("checking for kernel dump on device %s\n", device);
519
520	fd = open(device, (checkfor || keep) ? O_RDONLY : O_RDWR);
521	if (fd < 0) {
522		syslog(LOG_ERR, "%s: %m", device);
523		return;
524	}
525
526	error = ioctl(fd, DIOCGMEDIASIZE, &mediasize);
527	if (!error)
528		error = ioctl(fd, DIOCGSECTORSIZE, &sectorsize);
529	if (error) {
530		syslog(LOG_ERR,
531		    "couldn't find media and/or sector size of %s: %m", device);
532		goto closefd;
533	}
534
535	if (verbose) {
536		printf("mediasize = %lld bytes\n", (long long)mediasize);
537		printf("sectorsize = %u bytes\n", sectorsize);
538	}
539
540	if (sectorsize < sizeof(kdhl)) {
541		syslog(LOG_ERR,
542		    "Sector size is less the kernel dump header %zu",
543		    sizeof(kdhl));
544		goto closefd;
545	}
546
547	lasthd = mediasize - sectorsize;
548	if (temp == NULL) {
549		temp = malloc(sectorsize);
550		if (temp == NULL) {
551			syslog(LOG_ERR, "%m");
552			goto closefd;
553		}
554	}
555	if (lseek(fd, lasthd, SEEK_SET) != lasthd ||
556	    read(fd, temp, sectorsize) != (ssize_t)sectorsize) {
557		syslog(LOG_ERR,
558		    "error reading last dump header at offset %lld in %s: %m",
559		    (long long)lasthd, device);
560		goto closefd;
561	}
562	memcpy(&kdhl, temp, sizeof(kdhl));
563	istextdump = 0;
564	if (compare_magic(&kdhl, TEXTDUMPMAGIC)) {
565		if (verbose)
566			printf("textdump magic on last dump header on %s\n",
567			    device);
568		istextdump = 1;
569		if (dtoh32(kdhl.version) != KERNELDUMP_TEXT_VERSION) {
570			syslog(LOG_ERR,
571			    "unknown version (%d) in last dump header on %s",
572			    dtoh32(kdhl.version), device);
573
574			status = STATUS_BAD;
575			if (force == 0)
576				goto closefd;
577		}
578	} else if (compare_magic(&kdhl, KERNELDUMPMAGIC)) {
579		if (dtoh32(kdhl.version) != KERNELDUMPVERSION) {
580			syslog(LOG_ERR,
581			    "unknown version (%d) in last dump header on %s",
582			    dtoh32(kdhl.version), device);
583
584			status = STATUS_BAD;
585			if (force == 0)
586				goto closefd;
587		}
588	} else {
589		if (verbose)
590			printf("magic mismatch on last dump header on %s\n",
591			    device);
592
593		status = STATUS_BAD;
594		if (force == 0)
595			goto closefd;
596
597		if (compare_magic(&kdhl, KERNELDUMPMAGIC_CLEARED)) {
598			if (verbose)
599				printf("forcing magic on %s\n", device);
600			memcpy(kdhl.magic, KERNELDUMPMAGIC,
601			    sizeof kdhl.magic);
602		} else {
603			syslog(LOG_ERR, "unable to force dump - bad magic");
604			goto closefd;
605		}
606		if (dtoh32(kdhl.version) != KERNELDUMPVERSION) {
607			syslog(LOG_ERR,
608			    "unknown version (%d) in last dump header on %s",
609			    dtoh32(kdhl.version), device);
610
611			status = STATUS_BAD;
612			if (force == 0)
613				goto closefd;
614		}
615	}
616
617	nfound++;
618	if (clear)
619		goto nuke;
620
621	if (kerneldump_parity(&kdhl)) {
622		syslog(LOG_ERR,
623		    "parity error on last dump header on %s", device);
624		nerr++;
625		status = STATUS_BAD;
626		if (force == 0)
627			goto closefd;
628	}
629	dumpsize = dtoh64(kdhl.dumplength);
630	firsthd = lasthd - dumpsize - sectorsize;
631	if (lseek(fd, firsthd, SEEK_SET) != firsthd ||
632	    read(fd, temp, sectorsize) != (ssize_t)sectorsize) {
633		syslog(LOG_ERR,
634		    "error reading first dump header at offset %lld in %s: %m",
635		    (long long)firsthd, device);
636		nerr++;
637		goto closefd;
638	}
639	memcpy(&kdhf, temp, sizeof(kdhf));
640
641	if (verbose >= 2) {
642		printf("First dump headers:\n");
643		printheader(xostdout, &kdhf, device, bounds, -1);
644
645		printf("\nLast dump headers:\n");
646		printheader(xostdout, &kdhl, device, bounds, -1);
647		printf("\n");
648	}
649
650	if (memcmp(&kdhl, &kdhf, sizeof(kdhl))) {
651		syslog(LOG_ERR,
652		    "first and last dump headers disagree on %s", device);
653		nerr++;
654		status = STATUS_BAD;
655		if (force == 0)
656			goto closefd;
657	} else {
658		status = STATUS_GOOD;
659	}
660
661	if (checkfor) {
662		printf("A dump exists on %s\n", device);
663		close(fd);
664		exit(0);
665	}
666
667	if (kdhl.panicstring[0] != '\0')
668		syslog(LOG_ALERT, "reboot after panic: %.*s",
669		    (int)sizeof(kdhl.panicstring), kdhl.panicstring);
670	else
671		syslog(LOG_ALERT, "reboot");
672
673	if (verbose)
674		printf("Checking for available free space\n");
675
676	if (!check_space(savedir, dumpsize, bounds)) {
677		nerr++;
678		goto closefd;
679	}
680
681	writebounds(bounds + 1);
682
683	saved_dump_remove(bounds);
684
685	snprintf(infoname, sizeof(infoname), "info.%d", bounds);
686
687	/*
688	 * Create or overwrite any existing dump header files.
689	 */
690	fdinfo = open(infoname, O_WRONLY | O_CREAT | O_TRUNC, 0600);
691	if (fdinfo < 0) {
692		syslog(LOG_ERR, "%s: %m", infoname);
693		nerr++;
694		goto closefd;
695	}
696
697	oumask = umask(S_IRWXG|S_IRWXO); /* Restrict access to the core file. */
698	if (compress) {
699		snprintf(corename, sizeof(corename), "%s.%d.gz",
700		    istextdump ? "textdump.tar" : "vmcore", bounds);
701		fp = zopen(corename, "w");
702	} else {
703		snprintf(corename, sizeof(corename), "%s.%d",
704		    istextdump ? "textdump.tar" : "vmcore", bounds);
705		fp = fopen(corename, "w");
706	}
707	if (fp == NULL) {
708		syslog(LOG_ERR, "%s: %m", corename);
709		close(fdinfo);
710		nerr++;
711		goto closefd;
712	}
713	(void)umask(oumask);
714
715	info = fdopen(fdinfo, "w");
716
717	if (info == NULL) {
718		syslog(LOG_ERR, "fdopen failed: %m");
719		nerr++;
720		goto closeall;
721	}
722
723	xostyle = xo_get_style(NULL);
724	xoinfo = xo_create_to_file(info, xostyle, 0);
725	if (xoinfo == NULL) {
726		syslog(LOG_ERR, "%s: %m", infoname);
727		nerr++;
728		goto closeall;
729	}
730	xo_open_container_h(xoinfo, "crashdump");
731
732	if (verbose)
733		printheader(xostdout, &kdhl, device, bounds, status);
734
735	printheader(xoinfo, &kdhl, device, bounds, status);
736	xo_close_container_h(xoinfo, "crashdump");
737	xo_flush_h(xoinfo);
738	xo_finish_h(xoinfo);
739	fclose(info);
740
741	syslog(LOG_NOTICE, "writing %score to %s/%s",
742	    compress ? "compressed " : "", savedir, corename);
743
744	if (istextdump) {
745		if (DoTextdumpFile(fd, dumpsize, lasthd, buf, device,
746		    corename, fp) < 0)
747			goto closeall;
748	} else {
749		if (DoRegularFile(fd, dumpsize, buf, device, corename, fp)
750		    < 0)
751			goto closeall;
752	}
753	if (verbose)
754		printf("\n");
755
756	if (fclose(fp) < 0) {
757		syslog(LOG_ERR, "error on %s: %m", corename);
758		nerr++;
759		goto closefd;
760	}
761
762	symlinks_remove();
763	if (symlink(infoname, "info.last") == -1) {
764		syslog(LOG_WARNING, "unable to create symlink %s/%s: %m",
765		    savedir, "info.last");
766	}
767	if (compress) {
768		snprintf(linkname, sizeof(linkname), "%s.last.gz",
769		    istextdump ? "textdump.tar" : "vmcore");
770	} else {
771		snprintf(linkname, sizeof(linkname), "%s.last",
772		    istextdump ? "textdump.tar" : "vmcore");
773	}
774	if (symlink(corename, linkname) == -1) {
775		syslog(LOG_WARNING, "unable to create symlink %s/%s: %m",
776		    savedir, linkname);
777	}
778
779	nsaved++;
780
781	if (verbose)
782		printf("dump saved\n");
783
784nuke:
785	if (!keep) {
786		if (verbose)
787			printf("clearing dump header\n");
788		memcpy(kdhl.magic, KERNELDUMPMAGIC_CLEARED, sizeof(kdhl.magic));
789		memcpy(temp, &kdhl, sizeof(kdhl));
790		if (lseek(fd, lasthd, SEEK_SET) != lasthd ||
791		    write(fd, temp, sectorsize) != (ssize_t)sectorsize)
792			syslog(LOG_ERR,
793			    "error while clearing the dump header: %m");
794	}
795	xo_close_container_h(xostdout, "crashdump");
796	xo_finish_h(xostdout);
797	close(fd);
798	return;
799
800closeall:
801	fclose(fp);
802
803closefd:
804	close(fd);
805}
806
807static void
808usage(void)
809{
810	xo_error("%s\n%s\n%s\n",
811	    "usage: savecore -c [-v] [device ...]",
812	    "       savecore -C [-v] [device ...]",
813	    "       savecore [-fkvz] [-m maxdumps] [directory [device ...]]");
814	exit(1);
815}
816
817int
818main(int argc, char **argv)
819{
820	const char *savedir = ".";
821	struct fstab *fsp;
822	int i, ch, error;
823
824	checkfor = compress = clear = force = keep = verbose = 0;
825	nfound = nsaved = nerr = 0;
826
827	openlog("savecore", LOG_PERROR, LOG_DAEMON);
828	signal(SIGINFO, infohandler);
829
830	argc = xo_parse_args(argc, argv);
831	if (argc < 0)
832		exit(1);
833
834	while ((ch = getopt(argc, argv, "Ccfkm:vz")) != -1)
835		switch(ch) {
836		case 'C':
837			checkfor = 1;
838			break;
839		case 'c':
840			clear = 1;
841			break;
842		case 'f':
843			force = 1;
844			break;
845		case 'k':
846			keep = 1;
847			break;
848		case 'm':
849			maxdumps = atoi(optarg);
850			if (maxdumps <= 0) {
851				syslog(LOG_ERR, "Invalid maxdump value");
852				exit(1);
853			}
854			break;
855		case 'v':
856			verbose++;
857			break;
858		case 'z':
859			compress = 1;
860			break;
861		case '?':
862		default:
863			usage();
864		}
865	if (checkfor && (clear || force || keep))
866		usage();
867	if (clear && (compress || keep))
868		usage();
869	if (maxdumps > 0 && (checkfor || clear))
870		usage();
871	argc -= optind;
872	argv += optind;
873	if (argc >= 1 && !checkfor && !clear) {
874		error = chdir(argv[0]);
875		if (error) {
876			syslog(LOG_ERR, "chdir(%s): %m", argv[0]);
877			exit(1);
878		}
879		savedir = argv[0];
880		argc--;
881		argv++;
882	}
883	if (argc == 0) {
884		for (;;) {
885			fsp = getfsent();
886			if (fsp == NULL)
887				break;
888			if (strcmp(fsp->fs_vfstype, "swap") &&
889			    strcmp(fsp->fs_vfstype, "dump"))
890				continue;
891			DoFile(savedir, fsp->fs_spec);
892		}
893		endfsent();
894	} else {
895		for (i = 0; i < argc; i++)
896			DoFile(savedir, argv[i]);
897	}
898
899	/* Emit minimal output. */
900	if (nfound == 0) {
901		if (checkfor) {
902			if (verbose)
903				printf("No dump exists\n");
904			exit(1);
905		}
906		if (verbose)
907			syslog(LOG_WARNING, "no dumps found");
908	} else if (nsaved == 0) {
909		if (nerr != 0) {
910			if (verbose)
911				syslog(LOG_WARNING,
912				    "unsaved dumps found but not saved");
913			exit(1);
914		} else if (verbose)
915			syslog(LOG_WARNING, "no unsaved dumps found");
916	}
917
918	return (0);
919}
920
921static void
922infohandler(int sig __unused)
923{
924	got_siginfo = 1;
925}
926