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/param.h> 68 #include <sys/kerneldump.h> 69 #include <sys/diskslice.h> 70 #include <sys/ioctl.h> 71 #include <sys/mount.h> 72 #include <sys/stat.h> 73 #include <errno.h> 74 #include <fcntl.h> 75 #include <fstab.h> 76 #include <paths.h> 77 #include <stdarg.h> 78 #include <stdio.h> 79 #include <stdlib.h> 80 #include <string.h> 81 #include <syslog.h> 82 #include <time.h> 83 #include <unistd.h> 84 85 /* The size of the buffer used for I/O. */ 86 #define BUFFERSIZE (1024*1024) 87 88 #define STATUS_BAD 0 89 #define STATUS_GOOD 1 90 #define STATUS_UNKNOWN 2 91 92 static int checkfor, compress, clear, force, keep, verbose; /* flags */ 93 static int nfound, nsaved, nerr; /* statistics */ 94 95 extern FILE *zopen(const char *, const char *); 96 97 static void 98 printheader(FILE *f, const struct kerneldumpheader *h, const char *device, 99 int bounds, const int status) 100 { 101 uint64_t dumplen; 102 time_t t; 103 const char *stat_str; 104 105 fprintf(f, "Dump header from device %s\n", device); 106 fprintf(f, " Architecture: %s\n", h->architecture); 107 fprintf(f, " Architecture Version: %u\n", 108 dtoh32(h->architectureversion)); 109 dumplen = dtoh64(h->dumplength); 110 fprintf(f, " Dump Length: %lldB (%lld MB)\n", (long long)dumplen, 111 (long long)(dumplen >> 20)); 112 fprintf(f, " Blocksize: %d\n", dtoh32(h->blocksize)); 113 t = dtoh64(h->dumptime); 114 fprintf(f, " Dumptime: %s", ctime(&t)); 115 fprintf(f, " Hostname: %s\n", h->hostname); 116 fprintf(f, " Magic: %s\n", h->magic); 117 fprintf(f, " Version String: %s", h->versionstring); 118 fprintf(f, " Panic String: %s\n", h->panicstring); 119 fprintf(f, " Dump Parity: %u\n", h->parity); 120 fprintf(f, " Bounds: %d\n", bounds); 121 122 switch(status) { 123 case STATUS_BAD: 124 stat_str = "bad"; 125 break; 126 case STATUS_GOOD: 127 stat_str = "good"; 128 break; 129 default: 130 stat_str = "unknown"; 131 } 132 fprintf(f, " Dump Status: %s\n", stat_str); 133 fflush(f); 134 } 135 136 static int 137 getbounds(void) { 138 FILE *fp; 139 char buf[6]; 140 int ret; 141 142 ret = 0; 143 144 if ((fp = fopen("bounds", "r")) == NULL) { 145 if (verbose) 146 printf("unable to open bounds file, using 0\n"); 147 return (ret); 148 } 149 150 if (fgets(buf, sizeof buf, fp) == NULL) { 151 syslog(LOG_WARNING, "unable to read from bounds, using 0"); 152 fclose(fp); 153 return (ret); 154 } 155 156 errno = 0; 157 ret = (int)strtol(buf, NULL, 10); 158 if (ret == 0 && (errno == EINVAL || errno == ERANGE)) 159 syslog(LOG_WARNING, "invalid value found in bounds, using 0"); 160 return (ret); 161 } 162 163 static void 164 writebounds(int bounds) { 165 FILE *fp; 166 167 if ((fp = fopen("bounds", "w")) == NULL) { 168 syslog(LOG_WARNING, "unable to write to bounds file: %m"); 169 return; 170 } 171 172 if (verbose) 173 printf("bounds number: %d\n", bounds); 174 175 fprintf(fp, "%d\n", bounds); 176 fclose(fp); 177 } 178 179 /* 180 * Check that sufficient space is available on the disk that holds the 181 * save directory. 182 */ 183 static int 184 check_space(const char *savedir, off_t dumpsize) 185 { 186 FILE *fp; 187 off_t minfree, spacefree, totfree, needed; 188 struct statfs fsbuf; 189 char buf[100], path[MAXPATHLEN]; 190 191 if (statfs(savedir, &fsbuf) < 0) { 192 syslog(LOG_ERR, "%s: %m", savedir); 193 exit(1); 194 } 195 spacefree = ((off_t) fsbuf.f_bavail * fsbuf.f_bsize) / 1024; 196 totfree = ((off_t) fsbuf.f_bfree * fsbuf.f_bsize) / 1024; 197 198 (void)snprintf(path, sizeof(path), "%s/minfree", savedir); 199 if ((fp = fopen(path, "r")) == NULL) 200 minfree = 0; 201 else { 202 if (fgets(buf, sizeof(buf), fp) == NULL) 203 minfree = 0; 204 else 205 minfree = atoi(buf); 206 (void)fclose(fp); 207 } 208 209 needed = dumpsize / 1024 + 2; /* 2 for info file */ 210 if (((minfree > 0) ? spacefree : totfree) - needed < minfree) { 211 syslog(LOG_WARNING, 212 "no dump, not enough free space on device (%lld available, need %lld)", 213 (long long)(minfree > 0 ? spacefree : totfree), 214 (long long)needed); 215 return (0); 216 } 217 if (spacefree - needed < 0) 218 syslog(LOG_WARNING, 219 "dump performed, but free space threshold crossed"); 220 return (1); 221 } 222 223 #define BLOCKSIZE (1<<12) 224 #define BLOCKMASK (~(BLOCKSIZE-1)) 225 226 static void 227 DoFile(const char *savedir, const char *device) 228 { 229 static char *buf = NULL; 230 struct partinfo dpart; 231 struct kerneldumpheader kdhf, kdhl; 232 off_t mediasize, dumpsize, firsthd, lasthd, dmpcnt; 233 FILE *info, *fp, *fpkern; 234 mode_t oumask; 235 int fd, fdinfo, fdkernin, error, wl; 236 int nr, nw, hs, he = 0; 237 int bounds, status; 238 u_int sectorsize; 239 240 bounds = getbounds(); 241 dmpcnt = 0; 242 mediasize = 0; 243 status = STATUS_UNKNOWN; 244 245 if (buf == NULL) { 246 buf = malloc(BUFFERSIZE); 247 if (buf == NULL) { 248 syslog(LOG_ERR, "%m"); 249 return; 250 } 251 } 252 253 if (verbose) 254 printf("checking for kernel dump on device %s\n", device); 255 256 fd = open(device, O_RDWR); 257 if (fd < 0) { 258 syslog(LOG_ERR, "%s: %m", device); 259 return; 260 } 261 262 bzero(&dpart, sizeof(dpart)); 263 error = ioctl(fd, DIOCGPART, &dpart); 264 if (error) { 265 syslog(LOG_ERR, 266 "couldn't find media and/or sector size of %s: %m", device); 267 goto closefd; 268 } 269 mediasize = dpart.media_size; 270 sectorsize = dpart.media_blksize; 271 272 if (verbose) { 273 printf("mediasize = %lld\n", (long long)mediasize); 274 printf("sectorsize = %u\n", sectorsize); 275 } 276 277 lasthd = mediasize - sectorsize; 278 lseek(fd, lasthd, SEEK_SET); 279 error = read(fd, &kdhl, sizeof kdhl); 280 if (error != sizeof kdhl) { 281 syslog(LOG_ERR, 282 "error reading last dump header at offset %lld in %s: %m", 283 (long long)lasthd, device); 284 goto closefd; 285 } 286 if (memcmp(kdhl.magic, KERNELDUMPMAGIC, sizeof kdhl.magic)) { 287 if (verbose) 288 printf("magic mismatch on last dump header on %s\n", 289 device); 290 291 status = STATUS_BAD; 292 if (force == 0) 293 goto closefd; 294 295 if (memcmp(kdhl.magic, KERNELDUMPMAGIC_CLEARED, 296 sizeof kdhl.magic) == 0) { 297 if (verbose) 298 printf("forcing magic on %s\n", device); 299 memcpy(kdhl.magic, KERNELDUMPMAGIC, 300 sizeof kdhl.magic); 301 } else { 302 syslog(LOG_ERR, "unable to force dump - bad magic"); 303 goto closefd; 304 } 305 } 306 if (dtoh32(kdhl.version) != KERNELDUMPVERSION) { 307 syslog(LOG_ERR, 308 "unknown version (%d) in last dump header on %s", 309 dtoh32(kdhl.version), device); 310 311 status = STATUS_BAD; 312 if (force == 0) 313 goto closefd; 314 } 315 316 nfound++; 317 if (clear) 318 goto nuke; 319 320 if (kerneldump_parity(&kdhl)) { 321 syslog(LOG_ERR, 322 "parity error on last dump header on %s", device); 323 nerr++; 324 status = STATUS_BAD; 325 if (force == 0) 326 goto closefd; 327 } 328 dumpsize = dtoh64(kdhl.dumplength); 329 firsthd = lasthd - dumpsize - sizeof kdhf; 330 lseek(fd, firsthd, SEEK_SET); 331 error = read(fd, &kdhf, sizeof kdhf); 332 if (error != sizeof kdhf) { 333 syslog(LOG_ERR, 334 "error reading first dump header at offset %lld in %s: %m", 335 (long long)firsthd, device); 336 nerr++; 337 goto closefd; 338 } 339 340 if (verbose >= 2) { 341 printf("First dump headers:\n"); 342 printheader(stdout, &kdhf, device, bounds, -1); 343 344 printf("\nLast dump headers:\n"); 345 printheader(stdout, &kdhl, device, bounds, -1); 346 printf("\n"); 347 } 348 349 if (memcmp(&kdhl, &kdhf, sizeof kdhl)) { 350 syslog(LOG_ERR, 351 "first and last dump headers disagree on %s", device); 352 nerr++; 353 status = STATUS_BAD; 354 if (force == 0) 355 goto closefd; 356 } else { 357 status = STATUS_GOOD; 358 } 359 360 if (checkfor) { 361 printf("A dump exists on %s\n", device); 362 close(fd); 363 exit(0); 364 } 365 366 if (kdhl.panicstring[0]) 367 syslog(LOG_ALERT, "reboot after panic: %s", kdhl.panicstring); 368 else 369 syslog(LOG_ALERT, "reboot"); 370 371 if (verbose) 372 printf("Checking for available free space\n"); 373 if (!check_space(savedir, dumpsize)) { 374 nerr++; 375 goto closefd; 376 } 377 378 writebounds(bounds + 1); 379 380 /* 381 * Write kernel file. 382 */ 383 fdkernin = open(getbootfile(), O_RDONLY, 0); 384 if (fdkernin < 0) { 385 syslog(LOG_ERR, "%s: %m", getbootfile()); 386 } 387 388 if (compress) { 389 sprintf(buf, "kern.%d.gz", bounds); 390 fpkern = zopen(buf, "w"); 391 } else { 392 sprintf(buf, "kern.%d", bounds); 393 fpkern = fopen(buf, "w"); 394 } 395 if (fpkern == NULL) { 396 syslog(LOG_ERR, "%s: %m", buf); 397 close(fdkernin); 398 } 399 400 syslog(LOG_NOTICE, "writing %skernel to %s", 401 compress ? "compressed " : "", buf); 402 403 while ((nr = read(fdkernin, buf, BUFFERSIZE)) > 0) { 404 nw = fwrite(buf, 1, nr, fpkern); 405 if (nw != nr) { 406 syslog(LOG_ERR, "kern.%d: %m", bounds); 407 syslog(LOG_WARNING, 408 "WARNING: kernel may be incomplete"); 409 exit(1); 410 } 411 } 412 if (nr < 0) { 413 syslog(LOG_ERR, "%s: %m", getbootfile()); 414 syslog(LOG_WARNING, 415 "WARNING: kernel may be incomplete"); 416 exit(1); 417 } 418 fclose(fpkern); 419 close(fdkernin); 420 421 422 sprintf(buf, "info.%d", bounds); 423 424 /* 425 * Create or overwrite any existing dump header files. 426 */ 427 fdinfo = open(buf, O_WRONLY | O_CREAT | O_TRUNC, 0600); 428 if (fdinfo < 0) { 429 syslog(LOG_ERR, "%s: %m", buf); 430 nerr++; 431 goto closefd; 432 } 433 oumask = umask(S_IRWXG|S_IRWXO); /* Restrict access to the core file.*/ 434 if (compress) { 435 sprintf(buf, "vmcore.%d.gz", bounds); 436 fp = zopen(buf, "w"); 437 } else { 438 sprintf(buf, "vmcore.%d", bounds); 439 fp = fopen(buf, "w"); 440 } 441 if (fp == NULL) { 442 syslog(LOG_ERR, "%s: %m", buf); 443 close(fdinfo); 444 nerr++; 445 goto closefd; 446 } 447 (void)umask(oumask); 448 449 info = fdopen(fdinfo, "w"); 450 451 if (info == NULL) { 452 syslog(LOG_ERR, "fdopen failed: %m"); 453 nerr++; 454 goto closefd; 455 } 456 457 if (verbose) 458 printheader(stdout, &kdhl, device, bounds, status); 459 460 printheader(info, &kdhl, device, bounds, status); 461 fclose(info); 462 463 syslog(LOG_NOTICE, "writing %score to %s", 464 compress ? "compressed " : "", buf); 465 466 while (dumpsize > 0) { 467 wl = BUFFERSIZE; 468 if (wl > dumpsize) 469 wl = dumpsize; 470 nr = read(fd, buf, wl); 471 if (nr != wl) { 472 if (nr == 0) 473 syslog(LOG_WARNING, 474 "WARNING: EOF on dump device"); 475 else 476 syslog(LOG_ERR, "read error on %s: %m", device); 477 nerr++; 478 goto closeall; 479 } 480 if (compress) { 481 nw = fwrite(buf, 1, wl, fp); 482 } else { 483 for (nw = 0; nw < nr; nw = he) { 484 /* find a contiguous block of zeroes */ 485 for (hs = nw; hs < nr; hs += BLOCKSIZE) { 486 for (he = hs; he < nr && buf[he] == 0; 487 ++he) 488 /* nothing */ ; 489 /* is the hole long enough to matter? */ 490 if (he >= hs + BLOCKSIZE) 491 break; 492 } 493 494 /* back down to a block boundary */ 495 he &= BLOCKMASK; 496 497 /* 498 * 1) Don't go beyond the end of the buffer. 499 * 2) If the end of the buffer is less than 500 * BLOCKSIZE bytes away, we're at the end 501 * of the file, so just grab what's left. 502 */ 503 if (hs + BLOCKSIZE > nr) 504 hs = he = nr; 505 506 /* 507 * At this point, we have a partial ordering: 508 * nw <= hs <= he <= nr 509 * If hs > nw, buf[nw..hs] contains non-zero data. 510 * If he > hs, buf[hs..he] is all zeroes. 511 */ 512 if (hs > nw) 513 if (fwrite(buf + nw, hs - nw, 1, fp) 514 != 1) 515 break; 516 if (he > hs) 517 if (fseeko(fp, he - hs, SEEK_CUR) == -1) 518 break; 519 } 520 } 521 if (nw != wl) { 522 syslog(LOG_ERR, 523 "write error on vmcore.%d file: %m", bounds); 524 syslog(LOG_WARNING, 525 "WARNING: vmcore may be incomplete"); 526 nerr++; 527 goto closeall; 528 } 529 if (verbose) { 530 dmpcnt += wl; 531 printf("%llu\r", (unsigned long long)dmpcnt); 532 fflush(stdout); 533 } 534 dumpsize -= wl; 535 } 536 if (verbose) 537 printf("\n"); 538 539 if (fclose(fp) < 0) { 540 syslog(LOG_ERR, "error on vmcore.%d: %m", bounds); 541 nerr++; 542 goto closeall; 543 } 544 nsaved++; 545 546 if (verbose) 547 printf("dump saved\n"); 548 549 nuke: 550 if (clear || !keep) { 551 if (verbose) 552 printf("clearing dump header\n"); 553 memcpy(kdhl.magic, KERNELDUMPMAGIC_CLEARED, sizeof kdhl.magic); 554 lseek(fd, lasthd, SEEK_SET); 555 error = write(fd, &kdhl, sizeof kdhl); 556 if (error != sizeof kdhl) 557 syslog(LOG_ERR, 558 "error while clearing the dump header: %m"); 559 } 560 close(fd); 561 return; 562 563 closeall: 564 fclose(fp); 565 566 closefd: 567 close(fd); 568 } 569 570 static void 571 usage(void) 572 { 573 fprintf(stderr, "%s\n%s\n%s\n", 574 "usage: savecore -c", 575 " savecore -C [-v] [directory device]", 576 " savecore [-fkvz] [directory [device ...]]"); 577 exit (1); 578 } 579 580 int 581 main(int argc, char **argv) 582 { 583 const char *savedir = "."; 584 struct fstab *fsp; 585 int i, ch, error; 586 587 checkfor = compress = clear = force = keep = verbose = 0; 588 nfound = nsaved = nerr = 0; 589 590 openlog("savecore", LOG_PERROR, LOG_DAEMON); 591 592 while ((ch = getopt(argc, argv, "Ccfkvz")) != -1) 593 switch(ch) { 594 case 'C': 595 checkfor = 1; 596 break; 597 case 'c': 598 clear = 1; 599 break; 600 case 'k': 601 keep = 1; 602 break; 603 case 'v': 604 verbose++; 605 break; 606 case 'f': 607 force = 1; 608 break; 609 case 'z': 610 compress = 1; 611 break; 612 case '?': 613 default: 614 usage(); 615 } 616 if (checkfor && (clear || force || keep)) 617 usage(); 618 argc -= optind; 619 argv += optind; 620 if (argc >= 1) { 621 error = chdir(argv[0]); 622 if (error) { 623 syslog(LOG_ERR, "chdir(%s): %m", argv[0]); 624 exit(1); 625 } 626 savedir = argv[0]; 627 argc--; 628 argv++; 629 } 630 if (argc == 0) { 631 for (;;) { 632 fsp = getfsent(); 633 if (fsp == NULL) 634 break; 635 if (strcmp(fsp->fs_vfstype, "swap") && 636 strcmp(fsp->fs_vfstype, "dump")) 637 continue; 638 DoFile(savedir, fsp->fs_spec); 639 } 640 } else { 641 for (i = 0; i < argc; i++) 642 DoFile(savedir, argv[i]); 643 } 644 645 /* Emit minimal output. */ 646 if (nfound == 0) { 647 if (checkfor) { 648 printf("No dump exists\n"); 649 exit(1); 650 } 651 syslog(LOG_WARNING, "no dumps found"); 652 } 653 else if (nsaved == 0) { 654 if (nerr != 0) 655 syslog(LOG_WARNING, "unsaved dumps found but not saved"); 656 else 657 syslog(LOG_WARNING, "no unsaved dumps found"); 658 } 659 660 return (0); 661 } 662