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/mount.h> 74 #include <sys/stat.h> 75 #include <errno.h> 76 #include <fcntl.h> 77 #include <fstab.h> 78 #include <paths.h> 79 #include <stdarg.h> 80 #include <stdio.h> 81 #include <stdlib.h> 82 #include <string.h> 83 #include <syslog.h> 84 #include <time.h> 85 #include <unistd.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 94 static int checkfor, compress, clear, force, keep, verbose; /* flags */ 95 static int nfound, nsaved, nerr; /* statistics */ 96 97 extern FILE *zopen(const char *, const char *); 98 99 static void 100 printheader(FILE *f, const struct kerneldumpheader *h, const char *device, 101 int bounds, const int status) 102 { 103 uint64_t dumplen; 104 time_t t; 105 const char *stat_str; 106 107 fprintf(f, "Dump header from device %s\n", device); 108 fprintf(f, " Architecture: %s\n", h->architecture); 109 fprintf(f, " Architecture Version: %u\n", 110 dtoh32(h->architectureversion)); 111 dumplen = dtoh64(h->dumplength); 112 fprintf(f, " Dump Length: %lldB (%lld MB)\n", (long long)dumplen, 113 (long long)(dumplen >> 20)); 114 fprintf(f, " Blocksize: %d\n", dtoh32(h->blocksize)); 115 t = dtoh64(h->dumptime); 116 fprintf(f, " Dumptime: %s", ctime(&t)); 117 fprintf(f, " Hostname: %s\n", h->hostname); 118 fprintf(f, " Magic: %s\n", h->magic); 119 fprintf(f, " Version String: %s", h->versionstring); 120 fprintf(f, " Panic String: %s\n", h->panicstring); 121 fprintf(f, " Dump Parity: %u\n", h->parity); 122 fprintf(f, " Bounds: %d\n", bounds); 123 124 switch(status) { 125 case STATUS_BAD: 126 stat_str = "bad"; 127 break; 128 case STATUS_GOOD: 129 stat_str = "good"; 130 break; 131 default: 132 stat_str = "unknown"; 133 } 134 fprintf(f, " Dump Status: %s\n", stat_str); 135 fflush(f); 136 } 137 138 static int 139 getbounds(void) { 140 FILE *fp; 141 char buf[6]; 142 int ret; 143 144 ret = 0; 145 146 if ((fp = fopen("bounds", "r")) == NULL) { 147 if (verbose) 148 printf("unable to open bounds file, using 0\n"); 149 return (ret); 150 } 151 152 if (fgets(buf, sizeof buf, fp) == NULL) { 153 syslog(LOG_WARNING, "unable to read from bounds, using 0"); 154 fclose(fp); 155 return (ret); 156 } 157 158 errno = 0; 159 ret = (int)strtol(buf, NULL, 10); 160 if (ret == 0 && (errno == EINVAL || errno == ERANGE)) 161 syslog(LOG_WARNING, "invalid value found in bounds, using 0"); 162 return (ret); 163 } 164 165 static void 166 writebounds(int bounds) { 167 FILE *fp; 168 169 if ((fp = fopen("bounds", "w")) == NULL) { 170 syslog(LOG_WARNING, "unable to write to bounds file: %m"); 171 return; 172 } 173 174 if (verbose) 175 printf("bounds number: %d\n", bounds); 176 177 fprintf(fp, "%d\n", bounds); 178 fclose(fp); 179 } 180 181 /* 182 * Check that sufficient space is available on the disk that holds the 183 * save directory. 184 */ 185 static int 186 check_space(const char *savedir, off_t dumpsize) 187 { 188 FILE *fp; 189 off_t minfree, spacefree, totfree, needed; 190 struct statfs fsbuf; 191 char buf[100], path[MAXPATHLEN]; 192 193 if (statfs(savedir, &fsbuf) < 0) { 194 syslog(LOG_ERR, "%s: %m", savedir); 195 exit(1); 196 } 197 spacefree = ((off_t) fsbuf.f_bavail * fsbuf.f_bsize) / 1024; 198 totfree = ((off_t) fsbuf.f_bfree * fsbuf.f_bsize) / 1024; 199 200 (void)snprintf(path, sizeof(path), "%s/minfree", savedir); 201 if ((fp = fopen(path, "r")) == NULL) 202 minfree = 0; 203 else { 204 if (fgets(buf, sizeof(buf), fp) == NULL) 205 minfree = 0; 206 else 207 minfree = atoi(buf); 208 (void)fclose(fp); 209 } 210 211 needed = dumpsize / 1024 + 2; /* 2 for info file */ 212 if (((minfree > 0) ? spacefree : totfree) - needed < minfree) { 213 syslog(LOG_WARNING, 214 "no dump, not enough free space on device (%lld available, need %lld)", 215 (long long)(minfree > 0 ? spacefree : totfree), 216 (long long)needed); 217 return (0); 218 } 219 if (spacefree - needed < 0) 220 syslog(LOG_WARNING, 221 "dump performed, but free space threshold crossed"); 222 return (1); 223 } 224 225 #define BLOCKSIZE (1<<12) 226 #define BLOCKMASK (~(BLOCKSIZE-1)) 227 228 static void 229 DoFile(const char *savedir, const char *device) 230 { 231 static char *buf = NULL; 232 struct partinfo dpart; 233 struct kerneldumpheader kdhf, kdhl; 234 off_t mediasize, dumpsize, firsthd, lasthd, dmpcnt; 235 FILE *info, *fp, *fpkern; 236 mode_t oumask; 237 int fd, fdinfo, fdkernin, error, wl; 238 int nr, nw, hs, he = 0; 239 int bounds, status; 240 u_int sectorsize; 241 242 bounds = getbounds(); 243 dmpcnt = 0; 244 mediasize = 0; 245 status = STATUS_UNKNOWN; 246 247 if (buf == NULL) { 248 buf = malloc(BUFFERSIZE); 249 if (buf == NULL) { 250 syslog(LOG_ERR, "%m"); 251 return; 252 } 253 } 254 255 if (verbose) 256 printf("checking for kernel dump on device %s\n", device); 257 258 fd = open(device, O_RDWR); 259 if (fd < 0) { 260 syslog(LOG_ERR, "%s: %m", device); 261 return; 262 } 263 264 bzero(&dpart, sizeof(dpart)); 265 error = ioctl(fd, DIOCGPART, &dpart); 266 if (error) { 267 syslog(LOG_ERR, 268 "couldn't find media and/or sector size of %s: %m", device); 269 goto closefd; 270 } 271 mediasize = dpart.media_size; 272 sectorsize = dpart.media_blksize; 273 274 if (verbose) { 275 printf("mediasize = %lld\n", (long long)mediasize); 276 printf("sectorsize = %u\n", sectorsize); 277 } 278 279 lasthd = mediasize - sectorsize; 280 lseek(fd, lasthd, SEEK_SET); 281 error = read(fd, &kdhl, sizeof kdhl); 282 if (error != sizeof kdhl) { 283 syslog(LOG_ERR, 284 "error reading last dump header at offset %lld in %s: %m", 285 (long long)lasthd, device); 286 goto closefd; 287 } 288 if (memcmp(kdhl.magic, KERNELDUMPMAGIC, sizeof kdhl.magic)) { 289 if (verbose) 290 printf("magic mismatch on last dump header on %s\n", 291 device); 292 293 status = STATUS_BAD; 294 if (force == 0) 295 goto closefd; 296 297 if (memcmp(kdhl.magic, KERNELDUMPMAGIC_CLEARED, 298 sizeof kdhl.magic) == 0) { 299 if (verbose) 300 printf("forcing magic on %s\n", device); 301 memcpy(kdhl.magic, KERNELDUMPMAGIC, 302 sizeof kdhl.magic); 303 } else { 304 syslog(LOG_ERR, "unable to force dump - bad magic"); 305 goto closefd; 306 } 307 } 308 if (dtoh32(kdhl.version) != KERNELDUMPVERSION) { 309 syslog(LOG_ERR, 310 "unknown version (%d) in last dump header on %s", 311 dtoh32(kdhl.version), device); 312 313 status = STATUS_BAD; 314 if (force == 0) 315 goto closefd; 316 } 317 318 nfound++; 319 if (clear) 320 goto nuke; 321 322 if (kerneldump_parity(&kdhl)) { 323 syslog(LOG_ERR, 324 "parity error on last dump header on %s", device); 325 nerr++; 326 status = STATUS_BAD; 327 if (force == 0) 328 goto closefd; 329 } 330 dumpsize = dtoh64(kdhl.dumplength); 331 firsthd = lasthd - dumpsize - sizeof kdhf; 332 lseek(fd, firsthd, SEEK_SET); 333 error = read(fd, &kdhf, sizeof kdhf); 334 if (error != sizeof kdhf) { 335 syslog(LOG_ERR, 336 "error reading first dump header at offset %lld in %s: %m", 337 (long long)firsthd, device); 338 nerr++; 339 goto closefd; 340 } 341 342 if (verbose >= 2) { 343 printf("First dump headers:\n"); 344 printheader(stdout, &kdhf, device, bounds, -1); 345 346 printf("\nLast dump headers:\n"); 347 printheader(stdout, &kdhl, device, bounds, -1); 348 printf("\n"); 349 } 350 351 if (memcmp(&kdhl, &kdhf, sizeof kdhl)) { 352 syslog(LOG_ERR, 353 "first and last dump headers disagree on %s", device); 354 nerr++; 355 status = STATUS_BAD; 356 if (force == 0) 357 goto closefd; 358 } else { 359 status = STATUS_GOOD; 360 } 361 362 if (checkfor) { 363 printf("A dump exists on %s\n", device); 364 close(fd); 365 exit(0); 366 } 367 368 if (kdhl.panicstring[0]) 369 syslog(LOG_ALERT, "reboot after panic: %s", kdhl.panicstring); 370 else 371 syslog(LOG_ALERT, "reboot"); 372 373 if (verbose) 374 printf("Checking for available free space\n"); 375 if (!check_space(savedir, dumpsize)) { 376 nerr++; 377 goto closefd; 378 } 379 380 writebounds(bounds + 1); 381 382 /* 383 * Write kernel file. 384 */ 385 fdkernin = open(getbootfile(), O_RDONLY, 0); 386 if (fdkernin < 0) { 387 syslog(LOG_ERR, "%s: %m", getbootfile()); 388 } 389 390 if (compress) { 391 sprintf(buf, "kern.%d.gz", bounds); 392 fpkern = zopen(buf, "w"); 393 } else { 394 sprintf(buf, "kern.%d", bounds); 395 fpkern = fopen(buf, "w"); 396 } 397 if (fpkern == NULL) { 398 syslog(LOG_ERR, "%s: %m", buf); 399 close(fdkernin); 400 } 401 402 syslog(LOG_NOTICE, "writing %skernel to %s", 403 compress ? "compressed " : "", buf); 404 405 while ((nr = read(fdkernin, buf, sizeof(buf))) > 0) { 406 nw = fwrite(buf, 1, nr, fpkern); 407 if (nw != nr) { 408 syslog(LOG_ERR, "kern.%d: %m", bounds); 409 syslog(LOG_WARNING, 410 "WARNING: kernel may be incomplete"); 411 exit(1); 412 } 413 } 414 if (nr < 0) { 415 syslog(LOG_ERR, "%s: %m", getbootfile()); 416 syslog(LOG_WARNING, 417 "WARNING: kernel may be incomplete"); 418 exit(1); 419 } 420 fclose(fpkern); 421 close(fdkernin); 422 423 424 sprintf(buf, "info.%d", bounds); 425 426 /* 427 * Create or overwrite any existing dump header files. 428 */ 429 fdinfo = open(buf, O_WRONLY | O_CREAT | O_TRUNC, 0600); 430 if (fdinfo < 0) { 431 syslog(LOG_ERR, "%s: %m", buf); 432 nerr++; 433 goto closefd; 434 } 435 oumask = umask(S_IRWXG|S_IRWXO); /* Restrict access to the core file.*/ 436 if (compress) { 437 sprintf(buf, "vmcore.%d.gz", bounds); 438 fp = zopen(buf, "w"); 439 } else { 440 sprintf(buf, "vmcore.%d", bounds); 441 fp = fopen(buf, "w"); 442 } 443 if (fp == NULL) { 444 syslog(LOG_ERR, "%s: %m", buf); 445 close(fdinfo); 446 nerr++; 447 goto closefd; 448 } 449 (void)umask(oumask); 450 451 info = fdopen(fdinfo, "w"); 452 453 if (info == NULL) { 454 syslog(LOG_ERR, "fdopen failed: %m"); 455 nerr++; 456 goto closefd; 457 } 458 459 if (verbose) 460 printheader(stdout, &kdhl, device, bounds, status); 461 462 printheader(info, &kdhl, device, bounds, status); 463 fclose(info); 464 465 syslog(LOG_NOTICE, "writing %score to %s", 466 compress ? "compressed " : "", buf); 467 468 while (dumpsize > 0) { 469 wl = BUFFERSIZE; 470 if (wl > dumpsize) 471 wl = dumpsize; 472 nr = read(fd, buf, wl); 473 if (nr != wl) { 474 if (nr == 0) 475 syslog(LOG_WARNING, 476 "WARNING: EOF on dump device"); 477 else 478 syslog(LOG_ERR, "read error on %s: %m", device); 479 nerr++; 480 goto closeall; 481 } 482 if (compress) { 483 nw = fwrite(buf, 1, wl, fp); 484 } else { 485 for (nw = 0; nw < nr; nw = he) { 486 /* find a contiguous block of zeroes */ 487 for (hs = nw; hs < nr; hs += BLOCKSIZE) { 488 for (he = hs; he < nr && buf[he] == 0; 489 ++he) 490 /* nothing */ ; 491 /* is the hole long enough to matter? */ 492 if (he >= hs + BLOCKSIZE) 493 break; 494 } 495 496 /* back down to a block boundary */ 497 he &= BLOCKMASK; 498 499 /* 500 * 1) Don't go beyond the end of the buffer. 501 * 2) If the end of the buffer is less than 502 * BLOCKSIZE bytes away, we're at the end 503 * of the file, so just grab what's left. 504 */ 505 if (hs + BLOCKSIZE > nr) 506 hs = he = nr; 507 508 /* 509 * At this point, we have a partial ordering: 510 * nw <= hs <= he <= nr 511 * If hs > nw, buf[nw..hs] contains non-zero data. 512 * If he > hs, buf[hs..he] is all zeroes. 513 */ 514 if (hs > nw) 515 if (fwrite(buf + nw, hs - nw, 1, fp) 516 != 1) 517 break; 518 if (he > hs) 519 if (fseeko(fp, he - hs, SEEK_CUR) == -1) 520 break; 521 } 522 } 523 if (nw != wl) { 524 syslog(LOG_ERR, 525 "write error on vmcore.%d file: %m", bounds); 526 syslog(LOG_WARNING, 527 "WARNING: vmcore may be incomplete"); 528 nerr++; 529 goto closeall; 530 } 531 if (verbose) { 532 dmpcnt += wl; 533 printf("%llu\r", (unsigned long long)dmpcnt); 534 fflush(stdout); 535 } 536 dumpsize -= wl; 537 } 538 if (verbose) 539 printf("\n"); 540 541 if (fclose(fp) < 0) { 542 syslog(LOG_ERR, "error on vmcore.%d: %m", bounds); 543 nerr++; 544 goto closeall; 545 } 546 nsaved++; 547 548 if (verbose) 549 printf("dump saved\n"); 550 551 nuke: 552 if (clear || !keep) { 553 if (verbose) 554 printf("clearing dump header\n"); 555 memcpy(kdhl.magic, KERNELDUMPMAGIC_CLEARED, sizeof kdhl.magic); 556 lseek(fd, lasthd, SEEK_SET); 557 error = write(fd, &kdhl, sizeof kdhl); 558 if (error != sizeof kdhl) 559 syslog(LOG_ERR, 560 "error while clearing the dump header: %m"); 561 } 562 close(fd); 563 return; 564 565 closeall: 566 fclose(fp); 567 568 closefd: 569 close(fd); 570 } 571 572 static void 573 usage(void) 574 { 575 fprintf(stderr, "%s\n%s\n%s\n", 576 "usage: savecore -c", 577 " savecore -C [-v] [directory device]", 578 " savecore [-fkvz] [directory [device ...]]"); 579 exit (1); 580 } 581 582 int 583 main(int argc, char **argv) 584 { 585 const char *savedir = "."; 586 struct fstab *fsp; 587 int i, ch, error; 588 589 checkfor = compress = clear = force = keep = verbose = 0; 590 nfound = nsaved = nerr = 0; 591 592 openlog("savecore", LOG_PERROR, LOG_DAEMON); 593 594 while ((ch = getopt(argc, argv, "Ccfkvz")) != -1) 595 switch(ch) { 596 case 'C': 597 checkfor = 1; 598 break; 599 case 'c': 600 clear = 1; 601 break; 602 case 'k': 603 keep = 1; 604 break; 605 case 'v': 606 verbose++; 607 break; 608 case 'f': 609 force = 1; 610 break; 611 case 'z': 612 compress = 1; 613 break; 614 case '?': 615 default: 616 usage(); 617 } 618 if (checkfor && (clear || force || keep)) 619 usage(); 620 argc -= optind; 621 argv += optind; 622 if (argc >= 1) { 623 error = chdir(argv[0]); 624 if (error) { 625 syslog(LOG_ERR, "chdir(%s): %m", argv[0]); 626 exit(1); 627 } 628 savedir = argv[0]; 629 argc--; 630 argv++; 631 } 632 if (argc == 0) { 633 for (;;) { 634 fsp = getfsent(); 635 if (fsp == NULL) 636 break; 637 if (strcmp(fsp->fs_vfstype, "swap") && 638 strcmp(fsp->fs_vfstype, "dump")) 639 continue; 640 DoFile(savedir, fsp->fs_spec); 641 } 642 } else { 643 for (i = 0; i < argc; i++) 644 DoFile(savedir, argv[i]); 645 } 646 647 /* Emit minimal output. */ 648 if (nfound == 0) { 649 if (checkfor) { 650 printf("No dump exists\n"); 651 exit(1); 652 } 653 syslog(LOG_WARNING, "no dumps found"); 654 } 655 else if (nsaved == 0) { 656 if (nerr != 0) 657 syslog(LOG_WARNING, "unsaved dumps found but not saved"); 658 else 659 syslog(LOG_WARNING, "no unsaved dumps found"); 660 } 661 662 return (0); 663 } 664