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 35static 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";*/ 42static 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 62extern FILE *zopen __P((const char *fname, const char *mode, int bits)); 63 64#define ok(number) ((number) - KERNBASE) 65 66struct 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}; 83int cursyms[] = { X_DUMPDEV, X_DUMPLO, X_VERSION, X_DUMPMAG, -1 }; 84int dumpsyms[] = { X_TIME, X_DUMPSIZE, X_VERSION, X_PANICSTR, X_DUMPMAG, -1 }; 85 86struct 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. */ 98long dumplo; /* where dump starts on dumpdev */ 99int dumpmag; /* magic number in dump */ 100int dumpsize; /* amount of memory dumped */ 101 102char *kernel; 103char *dirname; /* directory to save dumps in */ 104char *ddname; /* name of dump device */ 105dev_t dumpdev; /* dump device */ 106int dumpfd; /* read/write descriptor on block dev */ 107time_t now; /* current date */ 108char panic_mesg[1024]; 109int panicstr; 110char vers[1024]; 111 112int clear, compress, force, verbose; /* flags */ 113 114void check_kmem __P((void)); 115int check_space __P((void)); 116void clear_dump __P((void)); 117int Create __P((char *, int)); 118int dump_exists __P((void)); 119char *find_dev __P((dev_t, int)); 120int get_crashtime __P((void)); 121void kmem_setup __P((void)); 122void log __P((int, char *, ...)); 123void Lseek __P((int, off_t, int)); 124int Open __P((char *, int rw)); 125int Read __P((int, void *, int)); 126char *rawname __P((char *s)); 127void save_core __P((void)); 128void usage __P((void)); 129void Write __P((int, void *, int)); 130 131int 132main(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 200void 201kmem_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 264void 265check_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 295void 296clear_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 305int 306dump_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 322char buf[1024 * 1024]; 323 324void 325save_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)) 340err1: 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)); 402err2: 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 454char * 455find_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 491char * 492rawname(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 510int 511get_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 531int 532check_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 576int 577Open(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 590int 591Read(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 605void 606Lseek(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 619int 620Create(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 634void 635Write(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 647void 648usage() 649{ 650 (void)syslog(LOG_ERR, "usage: savecore [-cfvz] [-N system] directory"); 651 exit(1); 652} 653