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 * 3. All advertising materials mentioning features or use of this software 47 * must display the following acknowledgement: 48 * This product includes software developed by the University of 49 * California, Berkeley and its contributors. 50 * 4. Neither the name of the University nor the names of its contributors 51 * may be used to endorse or promote products derived from this software 52 * without specific prior written permission. 53 * 54 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 55 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 56 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 57 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 58 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 59 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 60 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 61 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 62 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 63 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 64 * SUCH DAMAGE. 65 */ 66 67 #include <sys/cdefs.h> 68 69 #include <sys/param.h> 70 #include <sys/kerneldump.h> 71 #include <sys/diskslice.h> 72 #include <sys/ioctl.h> 73 #include <sys/param.h> 74 #include <sys/mount.h> 75 #include <sys/stat.h> 76 #include <errno.h> 77 #include <fcntl.h> 78 #include <fstab.h> 79 #include <paths.h> 80 #include <stdarg.h> 81 #include <stdio.h> 82 #include <stdlib.h> 83 #include <string.h> 84 #include <syslog.h> 85 #include <time.h> 86 #include <unistd.h> 87 88 /* The size of the buffer used for I/O. */ 89 #define BUFFERSIZE (1024*1024) 90 91 #define STATUS_BAD 0 92 #define STATUS_GOOD 1 93 #define STATUS_UNKNOWN 2 94 95 static int checkfor, compress, clear, force, keep, verbose; /* flags */ 96 static int nfound, nsaved, nerr; /* statistics */ 97 98 extern FILE *zopen(const char *, const char *); 99 100 static void 101 printheader(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 } 138 139 static int 140 getbounds(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 syslog(LOG_WARNING, "unable to read from bounds, using 0"); 155 fclose(fp); 156 return (ret); 157 } 158 159 errno = 0; 160 ret = (int)strtol(buf, NULL, 10); 161 if (ret == 0 && (errno == EINVAL || errno == ERANGE)) 162 syslog(LOG_WARNING, "invalid value found in bounds, using 0"); 163 return (ret); 164 } 165 166 static void 167 writebounds(int bounds) { 168 FILE *fp; 169 170 if ((fp = fopen("bounds", "w")) == NULL) { 171 syslog(LOG_WARNING, "unable to write to bounds file: %m"); 172 return; 173 } 174 175 if (verbose) 176 printf("bounds number: %d\n", bounds); 177 178 fprintf(fp, "%d\n", bounds); 179 fclose(fp); 180 } 181 182 /* 183 * Check that sufficient space is available on the disk that holds the 184 * save directory. 185 */ 186 static int 187 check_space(const char *savedir, off_t dumpsize) 188 { 189 FILE *fp; 190 off_t minfree, spacefree, totfree, needed; 191 struct statfs fsbuf; 192 char buf[100], path[MAXPATHLEN]; 193 194 if (statfs(savedir, &fsbuf) < 0) { 195 syslog(LOG_ERR, "%s: %m", savedir); 196 exit(1); 197 } 198 spacefree = ((off_t) fsbuf.f_bavail * fsbuf.f_bsize) / 1024; 199 totfree = ((off_t) fsbuf.f_bfree * fsbuf.f_bsize) / 1024; 200 201 (void)snprintf(path, sizeof(path), "%s/minfree", savedir); 202 if ((fp = fopen(path, "r")) == NULL) 203 minfree = 0; 204 else { 205 if (fgets(buf, sizeof(buf), fp) == NULL) 206 minfree = 0; 207 else 208 minfree = atoi(buf); 209 (void)fclose(fp); 210 } 211 212 needed = dumpsize / 1024 + 2; /* 2 for info file */ 213 if (((minfree > 0) ? spacefree : totfree) - needed < minfree) { 214 syslog(LOG_WARNING, 215 "no dump, not enough free space on device (%lld available, need %lld)", 216 (long long)(minfree > 0 ? spacefree : totfree), 217 (long long)needed); 218 return (0); 219 } 220 if (spacefree - needed < 0) 221 syslog(LOG_WARNING, 222 "dump performed, but free space threshold crossed"); 223 return (1); 224 } 225 226 #define BLOCKSIZE (1<<12) 227 #define BLOCKMASK (~(BLOCKSIZE-1)) 228 229 static void 230 DoFile(const char *savedir, const char *device) 231 { 232 static char *buf = NULL; 233 struct partinfo dpart; 234 struct kerneldumpheader kdhf, kdhl; 235 off_t mediasize, dumpsize, firsthd, lasthd, dmpcnt; 236 FILE *info, *fp, *fpkern; 237 mode_t oumask; 238 int fd, fdinfo, fdkernin, error, wl; 239 int nr, nw, hs, he = 0; 240 int bounds, status; 241 u_int sectorsize; 242 243 bounds = getbounds(); 244 dmpcnt = 0; 245 mediasize = 0; 246 status = STATUS_UNKNOWN; 247 248 if (buf == NULL) { 249 buf = malloc(BUFFERSIZE); 250 if (buf == NULL) { 251 syslog(LOG_ERR, "%m"); 252 return; 253 } 254 } 255 256 if (verbose) 257 printf("checking for kernel dump on device %s\n", device); 258 259 fd = open(device, O_RDWR); 260 if (fd < 0) { 261 syslog(LOG_ERR, "%s: %m", device); 262 return; 263 } 264 265 bzero(&dpart, sizeof(dpart)); 266 error = ioctl(fd, DIOCGPART, &dpart); 267 if (error) { 268 syslog(LOG_ERR, 269 "couldn't find media and/or sector size of %s: %m", device); 270 goto closefd; 271 } 272 mediasize = dpart.media_size; 273 sectorsize = dpart.media_blksize; 274 275 if (verbose) { 276 printf("mediasize = %lld\n", (long long)mediasize); 277 printf("sectorsize = %u\n", sectorsize); 278 } 279 280 lasthd = mediasize - sectorsize; 281 lseek(fd, lasthd, SEEK_SET); 282 error = read(fd, &kdhl, sizeof kdhl); 283 if (error != sizeof kdhl) { 284 syslog(LOG_ERR, 285 "error reading last dump header at offset %lld in %s: %m", 286 (long long)lasthd, device); 287 goto closefd; 288 } 289 if (memcmp(kdhl.magic, KERNELDUMPMAGIC, sizeof kdhl.magic)) { 290 if (verbose) 291 printf("magic mismatch on last dump header on %s\n", 292 device); 293 294 status = STATUS_BAD; 295 if (force == 0) 296 goto closefd; 297 298 if (memcmp(kdhl.magic, KERNELDUMPMAGIC_CLEARED, 299 sizeof kdhl.magic) == 0) { 300 if (verbose) 301 printf("forcing magic on %s\n", device); 302 memcpy(kdhl.magic, KERNELDUMPMAGIC, 303 sizeof kdhl.magic); 304 } else { 305 syslog(LOG_ERR, "unable to force dump - bad magic"); 306 goto closefd; 307 } 308 } 309 if (dtoh32(kdhl.version) != KERNELDUMPVERSION) { 310 syslog(LOG_ERR, 311 "unknown version (%d) in last dump header on %s", 312 dtoh32(kdhl.version), device); 313 314 status = STATUS_BAD; 315 if (force == 0) 316 goto closefd; 317 } 318 319 nfound++; 320 if (clear) 321 goto nuke; 322 323 if (kerneldump_parity(&kdhl)) { 324 syslog(LOG_ERR, 325 "parity error on last dump header on %s", device); 326 nerr++; 327 status = STATUS_BAD; 328 if (force == 0) 329 goto closefd; 330 } 331 dumpsize = dtoh64(kdhl.dumplength); 332 firsthd = lasthd - dumpsize - sizeof kdhf; 333 lseek(fd, firsthd, SEEK_SET); 334 error = read(fd, &kdhf, sizeof kdhf); 335 if (error != sizeof kdhf) { 336 syslog(LOG_ERR, 337 "error reading first dump header at offset %lld in %s: %m", 338 (long long)firsthd, device); 339 nerr++; 340 goto closefd; 341 } 342 343 if (verbose >= 2) { 344 printf("First dump headers:\n"); 345 printheader(stdout, &kdhf, device, bounds, -1); 346 347 printf("\nLast dump headers:\n"); 348 printheader(stdout, &kdhl, device, bounds, -1); 349 printf("\n"); 350 } 351 352 if (memcmp(&kdhl, &kdhf, sizeof kdhl)) { 353 syslog(LOG_ERR, 354 "first and last dump headers disagree on %s", device); 355 nerr++; 356 status = STATUS_BAD; 357 if (force == 0) 358 goto closefd; 359 } else { 360 status = STATUS_GOOD; 361 } 362 363 if (checkfor) { 364 printf("A dump exists on %s\n", device); 365 close(fd); 366 exit(0); 367 } 368 369 if (kdhl.panicstring[0]) 370 syslog(LOG_ALERT, "reboot after panic: %s", kdhl.panicstring); 371 else 372 syslog(LOG_ALERT, "reboot"); 373 374 if (verbose) 375 printf("Checking for available free space\n"); 376 if (!check_space(savedir, dumpsize)) { 377 nerr++; 378 goto closefd; 379 } 380 381 writebounds(bounds + 1); 382 383 /* 384 * Write kernel file. 385 */ 386 fdkernin = open(getbootfile(), O_RDONLY, 0); 387 if (fdkernin < 0) { 388 syslog(LOG_ERR, "%s: %m", getbootfile()); 389 } 390 391 if (compress) { 392 sprintf(buf, "kern.%d.gz", bounds); 393 fpkern = zopen(buf, "w"); 394 } else { 395 sprintf(buf, "kern.%d", bounds); 396 fpkern = fopen(buf, "w"); 397 } 398 if (fpkern == NULL) { 399 syslog(LOG_ERR, "%s: %m", buf); 400 close(fdkernin); 401 } 402 403 syslog(LOG_NOTICE, "writing %skernel to %s", 404 compress ? "compressed " : "", buf); 405 406 while ((nr = read(fdkernin, buf, sizeof(buf))) > 0) { 407 nw = fwrite(buf, 1, nr, fpkern); 408 if (nw != nr) { 409 syslog(LOG_ERR, "kern.%d: %m", bounds); 410 syslog(LOG_WARNING, 411 "WARNING: kernel may be incomplete"); 412 exit(1); 413 } 414 } 415 if (nr < 0) { 416 syslog(LOG_ERR, "%s: %m", getbootfile()); 417 syslog(LOG_WARNING, 418 "WARNING: kernel may be incomplete"); 419 exit(1); 420 } 421 fclose(fpkern); 422 close(fdkernin); 423 424 425 sprintf(buf, "info.%d", bounds); 426 427 /* 428 * Create or overwrite any existing dump header files. 429 */ 430 fdinfo = open(buf, O_WRONLY | O_CREAT | O_TRUNC, 0600); 431 if (fdinfo < 0) { 432 syslog(LOG_ERR, "%s: %m", buf); 433 nerr++; 434 goto closefd; 435 } 436 oumask = umask(S_IRWXG|S_IRWXO); /* Restrict access to the core file.*/ 437 if (compress) { 438 sprintf(buf, "vmcore.%d.gz", bounds); 439 fp = zopen(buf, "w"); 440 } else { 441 sprintf(buf, "vmcore.%d", bounds); 442 fp = fopen(buf, "w"); 443 } 444 if (fp == NULL) { 445 syslog(LOG_ERR, "%s: %m", buf); 446 close(fdinfo); 447 nerr++; 448 goto closefd; 449 } 450 (void)umask(oumask); 451 452 info = fdopen(fdinfo, "w"); 453 454 if (info == NULL) { 455 syslog(LOG_ERR, "fdopen failed: %m"); 456 nerr++; 457 goto closefd; 458 } 459 460 if (verbose) 461 printheader(stdout, &kdhl, device, bounds, status); 462 463 printheader(info, &kdhl, device, bounds, status); 464 fclose(info); 465 466 syslog(LOG_NOTICE, "writing %score to %s", 467 compress ? "compressed " : "", buf); 468 469 while (dumpsize > 0) { 470 wl = BUFFERSIZE; 471 if (wl > dumpsize) 472 wl = dumpsize; 473 nr = read(fd, buf, wl); 474 if (nr != wl) { 475 if (nr == 0) 476 syslog(LOG_WARNING, 477 "WARNING: EOF on dump device"); 478 else 479 syslog(LOG_ERR, "read error on %s: %m", device); 480 nerr++; 481 goto closeall; 482 } 483 if (compress) { 484 nw = fwrite(buf, 1, wl, fp); 485 } else { 486 for (nw = 0; nw < nr; nw = he) { 487 /* find a contiguous block of zeroes */ 488 for (hs = nw; hs < nr; hs += BLOCKSIZE) { 489 for (he = hs; he < nr && buf[he] == 0; 490 ++he) 491 /* nothing */ ; 492 /* is the hole long enough to matter? */ 493 if (he >= hs + BLOCKSIZE) 494 break; 495 } 496 497 /* back down to a block boundary */ 498 he &= BLOCKMASK; 499 500 /* 501 * 1) Don't go beyond the end of the buffer. 502 * 2) If the end of the buffer is less than 503 * BLOCKSIZE bytes away, we're at the end 504 * of the file, so just grab what's left. 505 */ 506 if (hs + BLOCKSIZE > nr) 507 hs = he = nr; 508 509 /* 510 * At this point, we have a partial ordering: 511 * nw <= hs <= he <= nr 512 * If hs > nw, buf[nw..hs] contains non-zero data. 513 * If he > hs, buf[hs..he] is all zeroes. 514 */ 515 if (hs > nw) 516 if (fwrite(buf + nw, hs - nw, 1, fp) 517 != 1) 518 break; 519 if (he > hs) 520 if (fseeko(fp, he - hs, SEEK_CUR) == -1) 521 break; 522 } 523 } 524 if (nw != wl) { 525 syslog(LOG_ERR, 526 "write error on vmcore.%d file: %m", bounds); 527 syslog(LOG_WARNING, 528 "WARNING: vmcore may be incomplete"); 529 nerr++; 530 goto closeall; 531 } 532 if (verbose) { 533 dmpcnt += wl; 534 printf("%llu\r", (unsigned long long)dmpcnt); 535 fflush(stdout); 536 } 537 dumpsize -= wl; 538 } 539 if (verbose) 540 printf("\n"); 541 542 if (fclose(fp) < 0) { 543 syslog(LOG_ERR, "error on vmcore.%d: %m", bounds); 544 nerr++; 545 goto closeall; 546 } 547 nsaved++; 548 549 if (verbose) 550 printf("dump saved\n"); 551 552 nuke: 553 if (clear || !keep) { 554 if (verbose) 555 printf("clearing dump header\n"); 556 memcpy(kdhl.magic, KERNELDUMPMAGIC_CLEARED, sizeof kdhl.magic); 557 lseek(fd, lasthd, SEEK_SET); 558 error = write(fd, &kdhl, sizeof kdhl); 559 if (error != sizeof kdhl) 560 syslog(LOG_ERR, 561 "error while clearing the dump header: %m"); 562 } 563 close(fd); 564 return; 565 566 closeall: 567 fclose(fp); 568 569 closefd: 570 close(fd); 571 } 572 573 static void 574 usage(void) 575 { 576 fprintf(stderr, "%s\n%s\n%s\n", 577 "usage: savecore -c", 578 " savecore -C [-v] [directory device]", 579 " savecore [-fkvz] [directory [device ...]]"); 580 exit (1); 581 } 582 583 int 584 main(int argc, char **argv) 585 { 586 const char *savedir = "."; 587 struct fstab *fsp; 588 int i, ch, error; 589 590 checkfor = compress = clear = force = keep = verbose = 0; 591 nfound = nsaved = nerr = 0; 592 593 openlog("savecore", LOG_PERROR, LOG_DAEMON); 594 595 while ((ch = getopt(argc, argv, "Ccfkvz")) != -1) 596 switch(ch) { 597 case 'C': 598 checkfor = 1; 599 break; 600 case 'c': 601 clear = 1; 602 break; 603 case 'k': 604 keep = 1; 605 break; 606 case 'v': 607 verbose++; 608 break; 609 case 'f': 610 force = 1; 611 break; 612 case 'z': 613 compress = 1; 614 break; 615 case '?': 616 default: 617 usage(); 618 } 619 if (checkfor && (clear || force || keep)) 620 usage(); 621 argc -= optind; 622 argv += optind; 623 if (argc >= 1) { 624 error = chdir(argv[0]); 625 if (error) { 626 syslog(LOG_ERR, "chdir(%s): %m", argv[0]); 627 exit(1); 628 } 629 savedir = argv[0]; 630 argc--; 631 argv++; 632 } 633 if (argc == 0) { 634 for (;;) { 635 fsp = getfsent(); 636 if (fsp == NULL) 637 break; 638 if (strcmp(fsp->fs_vfstype, "swap") && 639 strcmp(fsp->fs_vfstype, "dump")) 640 continue; 641 DoFile(savedir, fsp->fs_spec); 642 } 643 } else { 644 for (i = 0; i < argc; i++) 645 DoFile(savedir, argv[i]); 646 } 647 648 /* Emit minimal output. */ 649 if (nfound == 0) { 650 if (checkfor) { 651 printf("No dump exists\n"); 652 exit(1); 653 } 654 syslog(LOG_WARNING, "no dumps found"); 655 } 656 else if (nsaved == 0) { 657 if (nerr != 0) 658 syslog(LOG_WARNING, "unsaved dumps found but not saved"); 659 else 660 syslog(LOG_WARNING, "no unsaved dumps found"); 661 } 662 663 return (0); 664 } 665