savecore.c revision 1.20 1 /*-
2 * Copyright (c) 1986, 1992, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34 #ifndef lint
35 static char copyright[] =
36 "@(#) Copyright (c) 1986, 1992, 1993\n\
37 The Regents of the University of California. All rights reserved.\n";
38 #endif /* not lint */
39
40 #ifndef lint
41 /*static char sccsid[] = "from: @(#)savecore.c 8.3 (Berkeley) 1/2/94";*/
42 static char *rcsid = "$Id: savecore.c,v 1.20 1995/01/04 05:30:07 mycroft Exp $";
43 #endif /* not lint */
44
45 #include <sys/param.h>
46 #include <sys/stat.h>
47 #include <sys/mount.h>
48 #include <sys/syslog.h>
49 #include <sys/time.h>
50
51 #include <dirent.h>
52 #include <errno.h>
53 #include <fcntl.h>
54 #include <nlist.h>
55 #include <paths.h>
56 #include <stdio.h>
57 #include <stdlib.h>
58 #include <string.h>
59 #include <tzfile.h>
60 #include <unistd.h>
61
62 extern FILE *zopen __P((const char *fname, const char *mode, int bits));
63
64 #define ok(number) ((number) - KERNBASE)
65
66 struct nlist current_nl[] = { /* Namelist for currently running system. */
67 #define X_DUMPDEV 0
68 { "_dumpdev" },
69 #define X_DUMPLO 1
70 { "_dumplo" },
71 #define X_TIME 2
72 { "_time" },
73 #define X_DUMPSIZE 3
74 { "_dumpsize" },
75 #define X_VERSION 4
76 { "_version" },
77 #define X_PANICSTR 5
78 { "_panicstr" },
79 #define X_DUMPMAG 6
80 { "_dumpmag" },
81 { "" },
82 };
83 int cursyms[] = { X_DUMPDEV, X_DUMPLO, X_VERSION, X_DUMPMAG, -1 };
84 int dumpsyms[] = { X_TIME, X_DUMPSIZE, X_VERSION, X_PANICSTR, X_DUMPMAG, -1 };
85
86 struct nlist dump_nl[] = { /* Name list for dumped system. */
87 { "_dumpdev" }, /* Entries MUST be the same as */
88 { "_dumplo" }, /* those in current_nl[]. */
89 { "_time" },
90 { "_dumpsize" },
91 { "_version" },
92 { "_panicstr" },
93 { "_dumpmag" },
94 { "" },
95 };
96
97 /* Types match kernel declarations. */
98 long dumplo; /* where dump starts on dumpdev */
99 int dumpmag; /* magic number in dump */
100 int dumpsize; /* amount of memory dumped */
101
102 char *kernel;
103 char *dirname; /* directory to save dumps in */
104 char *ddname; /* name of dump device */
105 dev_t dumpdev; /* dump device */
106 int dumpfd; /* read/write descriptor on block dev */
107 time_t now; /* current date */
108 char panic_mesg[1024];
109 int panicstr;
110 char vers[1024];
111
112 int clear, compress, force, verbose; /* flags */
113
114 void check_kmem __P((void));
115 int check_space __P((void));
116 void clear_dump __P((void));
117 int Create __P((char *, int));
118 int dump_exists __P((void));
119 char *find_dev __P((dev_t, int));
120 int get_crashtime __P((void));
121 void kmem_setup __P((void));
122 void log __P((int, char *, ...));
123 void Lseek __P((int, off_t, int));
124 int Open __P((char *, int rw));
125 int Read __P((int, void *, int));
126 char *rawname __P((char *s));
127 void save_core __P((void));
128 void usage __P((void));
129 void Write __P((int, void *, int));
130
131 int
132 main(argc, argv)
133 int argc;
134 char *argv[];
135 {
136 int ch;
137
138 openlog("savecore", LOG_PERROR, LOG_DAEMON);
139
140 while ((ch = getopt(argc, argv, "cdfN:vz")) != -1)
141 switch(ch) {
142 case 'c':
143 clear = 1;
144 break;
145 case 'd': /* Not documented. */
146 case 'v':
147 verbose = 1;
148 break;
149 case 'f':
150 force = 1;
151 break;
152 case 'N':
153 kernel = optarg;
154 break;
155 case 'z':
156 compress = 1;
157 break;
158 case '?':
159 default:
160 usage();
161 }
162 argc -= optind;
163 argv += optind;
164
165 if (!clear) {
166 if (argc != 1 && argc != 2)
167 usage();
168 dirname = argv[0];
169 }
170 if (argc == 2)
171 kernel = argv[1];
172
173 (void)time(&now);
174 kmem_setup();
175
176 if (clear) {
177 clear_dump();
178 exit(0);
179 }
180
181 if (!dump_exists() && !force)
182 exit(1);
183
184 check_kmem();
185
186 if (panicstr)
187 syslog(LOG_ALERT, "reboot after panic: %s", panic_mesg);
188 else
189 syslog(LOG_ALERT, "reboot");
190
191 if ((!get_crashtime() || !check_space()) && !force)
192 exit(1);
193
194 save_core();
195
196 clear_dump();
197 exit(0);
198 }
199
200 void
201 kmem_setup()
202 {
203 FILE *fp;
204 int kmem, i;
205 char *dump_sys;
206
207 /*
208 * Some names we need for the currently running system, others for
209 * the system that was running when the dump was made. The values
210 * obtained from the current system are used to look for things in
211 * /dev/kmem that cannot be found in the dump_sys namelist, but are
212 * presumed to be the same (since the disk partitions are probably
213 * the same!)
214 */
215 if ((nlist(_PATH_UNIX, current_nl)) == -1)
216 syslog(LOG_ERR, "%s: nlist: %s", _PATH_UNIX, strerror(errno));
217 for (i = 0; cursyms[i] != -1; i++)
218 if (current_nl[cursyms[i]].n_value == 0) {
219 syslog(LOG_ERR, "%s: %s not in namelist",
220 _PATH_UNIX, current_nl[cursyms[i]].n_name);
221 exit(1);
222 }
223
224 dump_sys = kernel ? kernel : _PATH_UNIX;
225 if ((nlist(dump_sys, dump_nl)) == -1)
226 syslog(LOG_ERR, "%s: nlist: %s", dump_sys, strerror(errno));
227 for (i = 0; dumpsyms[i] != -1; i++)
228 if (dump_nl[dumpsyms[i]].n_value == 0) {
229 syslog(LOG_ERR, "%s: %s not in namelist",
230 dump_sys, dump_nl[dumpsyms[i]].n_name);
231 exit(1);
232 }
233
234 kmem = Open(_PATH_KMEM, O_RDONLY);
235 Lseek(kmem, (off_t)current_nl[X_DUMPDEV].n_value, L_SET);
236 (void)Read(kmem, &dumpdev, sizeof(dumpdev));
237 if (dumpdev == NODEV) {
238 syslog(LOG_WARNING, "no core dump (no dumpdev)");
239 exit(1);
240 }
241 Lseek(kmem, (off_t)current_nl[X_DUMPLO].n_value, L_SET);
242 (void)Read(kmem, &dumplo, sizeof(dumplo));
243 if (verbose)
244 (void)printf("dumplo = %d (%d * %d)\n",
245 dumplo, dumplo/DEV_BSIZE, DEV_BSIZE);
246 Lseek(kmem, (off_t)current_nl[X_DUMPMAG].n_value, L_SET);
247 (void)Read(kmem, &dumpmag, sizeof(dumpmag));
248 dumplo *= DEV_BSIZE;
249 ddname = find_dev(dumpdev, S_IFBLK);
250 dumpfd = Open(ddname, O_RDWR);
251 fp = fdopen(kmem, "r");
252 if (fp == NULL) {
253 syslog(LOG_ERR, "%s: fdopen: %m", _PATH_KMEM);
254 exit(1);
255 }
256 if (kernel)
257 return;
258 (void)fseek(fp, (off_t)current_nl[X_VERSION].n_value, L_SET);
259 (void)fgets(vers, sizeof(vers), fp);
260
261 /* Don't fclose(fp), we use dumpfd later. */
262 }
263
264 void
265 check_kmem()
266 {
267 register char *cp;
268 FILE *fp;
269 char core_vers[1024];
270
271 fp = fdopen(dumpfd, "r");
272 if (fp == NULL) {
273 syslog(LOG_ERR, "%s: fdopen: %m", ddname);
274 exit(1);
275 }
276 fseek(fp, (off_t)(dumplo + ok(dump_nl[X_VERSION].n_value)), L_SET);
277 fgets(core_vers, sizeof(core_vers), fp);
278 if (strcmp(vers, core_vers) && kernel == 0)
279 syslog(LOG_WARNING,
280 "warning: %s version mismatch:\n\t%s\nand\t%s\n",
281 _PATH_UNIX, vers, core_vers);
282 (void)fseek(fp,
283 (off_t)(dumplo + ok(dump_nl[X_PANICSTR].n_value)), L_SET);
284 (void)fread(&panicstr, sizeof(panicstr), 1, fp);
285 if (panicstr) {
286 (void)fseek(fp, dumplo + ok(panicstr), L_SET);
287 cp = panic_mesg;
288 do
289 *cp = getc(fp);
290 while (*cp++ && cp < &panic_mesg[sizeof(panic_mesg)]);
291 }
292 /* Don't fclose(fp), we use dumpfd later. */
293 }
294
295 void
296 clear_dump()
297 {
298 long newdumplo;
299
300 newdumplo = 0;
301 Lseek(dumpfd, (off_t)(dumplo + ok(dump_nl[X_DUMPMAG].n_value)), L_SET);
302 Write(dumpfd, &newdumplo, sizeof(newdumplo));
303 }
304
305 int
306 dump_exists()
307 {
308 int newdumpmag;
309
310 Lseek(dumpfd, (off_t)(dumplo + ok(dump_nl[X_DUMPMAG].n_value)), L_SET);
311 (void)Read(dumpfd, &newdumpmag, sizeof(newdumpmag));
312 if (newdumpmag != dumpmag) {
313 if (verbose)
314 syslog(LOG_WARNING, "magic number mismatch (%x != %x)",
315 newdumpmag, dumpmag);
316 syslog(LOG_WARNING, "no core dump");
317 return (0);
318 }
319 return (1);
320 }
321
322 char buf[1024 * 1024];
323
324 void
325 save_core()
326 {
327 register FILE *fp;
328 register int bounds, ifd, nr, nw, ofd;
329 char *rawp, path[MAXPATHLEN];
330
331 /*
332 * Get the current number and update the bounds file. Do the update
333 * now, because may fail later and don't want to overwrite anything.
334 */
335 (void)snprintf(path, sizeof(path), "%s/bounds", dirname);
336 if ((fp = fopen(path, "r")) == NULL)
337 goto err1;
338 if (fgets(buf, sizeof(buf), fp) == NULL) {
339 if (ferror(fp))
340 err1: syslog(LOG_WARNING, "%s: %s", path, strerror(errno));
341 bounds = 0;
342 } else
343 bounds = atoi(buf);
344 if (fp != NULL)
345 (void)fclose(fp);
346 if ((fp = fopen(path, "w")) == NULL)
347 syslog(LOG_ERR, "%s: %m", path);
348 else {
349 (void)fprintf(fp, "%d\n", bounds + 1);
350 (void)fclose(fp);
351 }
352 (void)fclose(fp);
353
354 /* Create the core file. */
355 (void)snprintf(path, sizeof(path), "%s/netbsd.%d%s.core",
356 dirname, bounds, compress ? ".Z" : "");
357 if (compress) {
358 if ((fp = zopen(path, "w", 0)) == NULL) {
359 syslog(LOG_ERR, "%s: %s", path, strerror(errno));
360 exit(1);
361 }
362 } else
363 ofd = Create(path, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
364
365 /* Open the raw device. */
366 rawp = rawname(ddname);
367 if ((ifd = open(rawp, O_RDONLY)) == -1) {
368 syslog(LOG_WARNING, "%s: %m; using block device", rawp);
369 ifd = dumpfd;
370 }
371
372 /* Read the dump size. */
373 Lseek(dumpfd, (off_t)(dumplo + ok(dump_nl[X_DUMPSIZE].n_value)), L_SET);
374 (void)Read(dumpfd, &dumpsize, sizeof(dumpsize));
375
376 /* Seek to the start of the core. */
377 Lseek(ifd, (off_t)dumplo, L_SET);
378
379 /* Copy the core file. */
380 dumpsize *= getpagesize();
381 syslog(LOG_NOTICE, "writing %score to %s",
382 compress ? "compressed " : "", path);
383 for (; dumpsize > 0; dumpsize -= nr) {
384 (void)printf("%6dK\r", dumpsize / 1024);
385 (void)fflush(stdout);
386 nr = read(ifd, buf, MIN(dumpsize, sizeof(buf)));
387 if (nr <= 0) {
388 if (nr == 0)
389 syslog(LOG_WARNING,
390 "WARNING: EOF on dump device");
391 else
392 syslog(LOG_ERR, "%s: %m", rawp);
393 goto err2;
394 }
395 if (compress)
396 nw = fwrite(buf, 1, nr, fp);
397 else
398 nw = write(ofd, buf, nr);
399 if (nw != nr) {
400 syslog(LOG_ERR, "%s: %s",
401 path, strerror(nw == 0 ? EIO : errno));
402 err2: syslog(LOG_WARNING,
403 "WARNING: core may be incomplete");
404 (void)printf("\n");
405 exit(1);
406 }
407 }
408 (void)printf("\n");
409 (void)close(ifd);
410 if (compress)
411 (void)fclose(fp);
412 else
413 (void)close(ofd);
414
415 /* Copy the kernel. */
416 ifd = Open(kernel ? kernel : _PATH_UNIX, O_RDONLY);
417 (void)snprintf(path, sizeof(path), "%s/netbsd.%d%s",
418 dirname, bounds, compress ? ".Z" : "");
419 if (compress) {
420 if ((fp = zopen(path, "w", 0)) == NULL) {
421 syslog(LOG_ERR, "%s: %s", path, strerror(errno));
422 exit(1);
423 }
424 } else
425 ofd = Create(path, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
426 syslog(LOG_NOTICE, "writing %skernel to %s",
427 compress ? "compressed " : "", path);
428 while ((nr = read(ifd, buf, sizeof(buf))) > 0) {
429 if (compress)
430 nw = fwrite(buf, 1, nr, fp);
431 else
432 nw = write(ofd, buf, nr);
433 if (nw != nr) {
434 syslog(LOG_ERR, "%s: %s",
435 path, strerror(nw == 0 ? EIO : errno));
436 syslog(LOG_WARNING,
437 "WARNING: kernel may be incomplete");
438 exit(1);
439 }
440 }
441 if (nr < 0) {
442 syslog(LOG_ERR, "%s: %s",
443 kernel ? kernel : _PATH_UNIX, strerror(errno));
444 syslog(LOG_WARNING,
445 "WARNING: kernel may be incomplete");
446 exit(1);
447 }
448 if (compress)
449 (void)fclose(fp);
450 else
451 (void)close(ofd);
452 }
453
454 char *
455 find_dev(dev, type)
456 register dev_t dev;
457 register int type;
458 {
459 register DIR *dfd;
460 struct dirent *dir;
461 struct stat sb;
462 char *dp, devname[MAXPATHLEN + 1];
463
464 if ((dfd = opendir(_PATH_DEV)) == NULL) {
465 syslog(LOG_ERR, "%s: %s", _PATH_DEV, strerror(errno));
466 exit(1);
467 }
468 (void)strcpy(devname, _PATH_DEV);
469 while ((dir = readdir(dfd))) {
470 (void)strcpy(devname + sizeof(_PATH_DEV) - 1, dir->d_name);
471 if (lstat(devname, &sb)) {
472 syslog(LOG_ERR, "%s: %s", devname, strerror(errno));
473 continue;
474 }
475 if ((sb.st_mode & S_IFMT) != type)
476 continue;
477 if (dev == sb.st_rdev) {
478 closedir(dfd);
479 if ((dp = strdup(devname)) == NULL) {
480 syslog(LOG_ERR, "%s", strerror(errno));
481 exit(1);
482 }
483 return (dp);
484 }
485 }
486 closedir(dfd);
487 syslog(LOG_ERR, "can't find device %d/%d", major(dev), minor(dev));
488 exit(1);
489 }
490
491 char *
492 rawname(s)
493 char *s;
494 {
495 char *sl, name[MAXPATHLEN];
496
497 if ((sl = strrchr(s, '/')) == NULL || sl[1] == '0') {
498 syslog(LOG_ERR,
499 "can't make raw dump device name from %s", s);
500 return (s);
501 }
502 (void)snprintf(name, sizeof(name), "%.*s/r%s", sl - s, s, sl + 1);
503 if ((sl = strdup(name)) == NULL) {
504 syslog(LOG_ERR, "%s", strerror(errno));
505 exit(1);
506 }
507 return (sl);
508 }
509
510 int
511 get_crashtime()
512 {
513 time_t dumptime; /* Time the dump was taken. */
514
515 Lseek(dumpfd, (off_t)(dumplo + ok(dump_nl[X_TIME].n_value)), L_SET);
516 (void)Read(dumpfd, &dumptime, sizeof(dumptime));
517 if (dumptime == 0) {
518 if (verbose)
519 syslog(LOG_ERR, "dump time is zero");
520 return (0);
521 }
522 (void)printf("savecore: system went down at %s", ctime(&dumptime));
523 #define LEEWAY (7 * SECSPERDAY)
524 if (dumptime < now - LEEWAY || dumptime > now + LEEWAY) {
525 (void)printf("dump time is unreasonable\n");
526 return (0);
527 }
528 return (1);
529 }
530
531 int
532 check_space()
533 {
534 register FILE *fp;
535 char *tkernel;
536 off_t minfree, spacefree, kernelsize, needed;
537 struct stat st;
538 struct statfs fsbuf;
539 char buf[100], path[MAXPATHLEN];
540
541 tkernel = kernel ? kernel : _PATH_UNIX;
542 if (stat(tkernel, &st) < 0) {
543 syslog(LOG_ERR, "%s: %m", tkernel);
544 exit(1);
545 }
546 kernelsize = st.st_blocks * S_BLKSIZE;
547 if (statfs(dirname, &fsbuf) < 0) {
548 syslog(LOG_ERR, "%s: %m", dirname);
549 exit(1);
550 }
551 spacefree = (fsbuf.f_bavail * fsbuf.f_bsize) / 1024;
552
553 (void)snprintf(path, sizeof(path), "%s/minfree", dirname);
554 if ((fp = fopen(path, "r")) == NULL)
555 minfree = 0;
556 else {
557 if (fgets(buf, sizeof(buf), fp) == NULL)
558 minfree = 0;
559 else
560 minfree = atoi(buf);
561 (void)fclose(fp);
562 }
563
564 needed = (dumpsize + kernelsize) / 1024;
565 if (minfree > 0 && spacefree - needed < minfree) {
566 syslog(LOG_WARNING,
567 "no dump, not enough free space on device");
568 return (0);
569 }
570 if (spacefree - needed < minfree)
571 syslog(LOG_WARNING,
572 "dump performed, but free space threshold crossed");
573 return (1);
574 }
575
576 int
577 Open(name, rw)
578 char *name;
579 int rw;
580 {
581 int fd;
582
583 if ((fd = open(name, rw, 0)) < 0) {
584 syslog(LOG_ERR, "%s: %m", name);
585 exit(1);
586 }
587 return (fd);
588 }
589
590 int
591 Read(fd, bp, size)
592 int fd, size;
593 void *bp;
594 {
595 int nr;
596
597 nr = read(fd, bp, size);
598 if (nr != size) {
599 syslog(LOG_ERR, "read: %m");
600 exit(1);
601 }
602 return (nr);
603 }
604
605 void
606 Lseek(fd, off, flag)
607 int fd, flag;
608 off_t off;
609 {
610 off_t ret;
611
612 ret = lseek(fd, off, flag);
613 if (ret == -1) {
614 syslog(LOG_ERR, "lseek: %m");
615 exit(1);
616 }
617 }
618
619 int
620 Create(file, mode)
621 char *file;
622 int mode;
623 {
624 register int fd;
625
626 fd = open(file, O_WRONLY | O_CREAT | O_TRUNC, mode);
627 if (fd < 0) {
628 syslog(LOG_ERR, "%s: %m", file);
629 exit(1);
630 }
631 return (fd);
632 }
633
634 void
635 Write(fd, bp, size)
636 int fd, size;
637 void *bp;
638 {
639 int n;
640
641 if ((n = write(fd, bp, size)) < size) {
642 syslog(LOG_ERR, "write: %s", strerror(n == -1 ? errno : EIO));
643 exit(1);
644 }
645 }
646
647 void
648 usage()
649 {
650 (void)syslog(LOG_ERR, "usage: savecore [-cfvz] [-N system] directory");
651 exit(1);
652 }
653