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. Neither the name of the University nor the names of its contributors 47 * may be used to endorse or promote products derived from this software 48 * without specific prior written permission. 49 * 50 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 51 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 52 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 53 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 54 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 55 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 56 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 57 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 58 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 59 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 60 * SUCH DAMAGE. 61 */ 62 63 #include <sys/param.h> 64 #include <sys/kerneldump.h> 65 #include <sys/diskslice.h> 66 #include <sys/ioctl.h> 67 #include <sys/mount.h> 68 #include <sys/stat.h> 69 #include <errno.h> 70 #include <fcntl.h> 71 #include <fstab.h> 72 #include <paths.h> 73 #include <stdarg.h> 74 #include <stdio.h> 75 #include <stdlib.h> 76 #include <string.h> 77 #include <syslog.h> 78 #include <time.h> 79 #include <unistd.h> 80 81 /* The size of the buffer used for I/O. */ 82 #define BUFFERSIZE (1024*1024) 83 84 #define STATUS_BAD 0 85 #define STATUS_GOOD 1 86 #define STATUS_UNKNOWN 2 87 88 static int checkfor, compress, clear, force, keep, verbose; /* flags */ 89 static int nfound, nsaved, nerr; /* statistics */ 90 91 extern FILE *zopen(const char *, const char *); 92 93 static void 94 printheader(FILE *f, const struct kerneldumpheader *h, const char *device, 95 int bounds, const int status) 96 { 97 uint64_t dumplen; 98 time_t t; 99 const char *stat_str; 100 101 fprintf(f, "Dump header from device %s\n", device); 102 fprintf(f, " Architecture: %s\n", h->architecture); 103 fprintf(f, " Architecture Version: %u\n", 104 dtoh32(h->architectureversion)); 105 dumplen = dtoh64(h->dumplength); 106 fprintf(f, " Dump Length: %lldB (%lld MB)\n", (long long)dumplen, 107 (long long)(dumplen >> 20)); 108 fprintf(f, " Blocksize: %d\n", dtoh32(h->blocksize)); 109 t = dtoh64(h->dumptime); 110 fprintf(f, " Dumptime: %s", ctime(&t)); 111 fprintf(f, " Hostname: %s\n", h->hostname); 112 fprintf(f, " Magic: %s\n", h->magic); 113 fprintf(f, " Version String: %s", h->versionstring); 114 fprintf(f, " Panic String: %s\n", h->panicstring); 115 fprintf(f, " Dump Parity: %u\n", h->parity); 116 fprintf(f, " Bounds: %d\n", bounds); 117 118 switch(status) { 119 case STATUS_BAD: 120 stat_str = "bad"; 121 break; 122 case STATUS_GOOD: 123 stat_str = "good"; 124 break; 125 default: 126 stat_str = "unknown"; 127 } 128 fprintf(f, " Dump Status: %s\n", stat_str); 129 fflush(f); 130 } 131 132 static int 133 getbounds(void) { 134 FILE *fp; 135 char buf[6]; 136 int ret; 137 138 ret = 0; 139 140 if ((fp = fopen("bounds", "r")) == NULL) { 141 if (verbose) 142 printf("unable to open bounds file, using 0\n"); 143 return (ret); 144 } 145 146 if (fgets(buf, sizeof buf, fp) == NULL) { 147 syslog(LOG_WARNING, "unable to read from bounds, using 0"); 148 fclose(fp); 149 return (ret); 150 } 151 152 errno = 0; 153 ret = (int)strtol(buf, NULL, 10); 154 if (ret == 0 && (errno == EINVAL || errno == ERANGE)) 155 syslog(LOG_WARNING, "invalid value found in bounds, using 0"); 156 fclose(fp); 157 return (ret); 158 } 159 160 static void 161 writebounds(int bounds) { 162 FILE *fp; 163 164 if ((fp = fopen("bounds", "w")) == NULL) { 165 syslog(LOG_WARNING, "unable to write to bounds file: %m"); 166 return; 167 } 168 169 if (verbose) 170 printf("bounds number: %d\n", bounds); 171 172 fprintf(fp, "%d\n", bounds); 173 fclose(fp); 174 } 175 176 /* 177 * Check that sufficient space is available on the disk that holds the 178 * save directory. 179 */ 180 static int 181 check_space(const char *savedir, off_t dumpsize) 182 { 183 FILE *fp; 184 off_t minfree, spacefree, totfree, needed; 185 struct statfs fsbuf; 186 char buf[100], path[MAXPATHLEN]; 187 188 if (statfs(savedir, &fsbuf) < 0) { 189 syslog(LOG_ERR, "%s: %m", savedir); 190 exit(1); 191 } 192 spacefree = ((off_t) fsbuf.f_bavail * fsbuf.f_bsize) / 1024; 193 totfree = ((off_t) fsbuf.f_bfree * fsbuf.f_bsize) / 1024; 194 195 (void)snprintf(path, sizeof(path), "%s/minfree", savedir); 196 if ((fp = fopen(path, "r")) == NULL) 197 minfree = 0; 198 else { 199 if (fgets(buf, sizeof(buf), fp) == NULL) 200 minfree = 0; 201 else 202 minfree = atoi(buf); 203 (void)fclose(fp); 204 } 205 206 needed = dumpsize / 1024 + 2; /* 2 for info file */ 207 if (((minfree > 0) ? spacefree : totfree) - needed < minfree) { 208 syslog(LOG_WARNING, 209 "no dump, not enough free space on device (%lld available, need %lld)", 210 (long long)(minfree > 0 ? spacefree : totfree), 211 (long long)needed); 212 return (0); 213 } 214 if (spacefree - needed < 0) 215 syslog(LOG_WARNING, 216 "dump performed, but free space threshold crossed"); 217 return (1); 218 } 219 220 #define BLOCKSIZE (1<<12) 221 #define BLOCKMASK (~(BLOCKSIZE-1)) 222 223 static void 224 DoFile(const char *savedir, const char *device) 225 { 226 static char *buf = NULL; 227 struct partinfo dpart; 228 struct kerneldumpheader kdhf, kdhl; 229 off_t mediasize, dumpsize, firsthd, lasthd, dmpcnt; 230 FILE *info, *fp, *fpkern; 231 mode_t oumask; 232 int fd, fdinfo, fdkernin, error, wl; 233 int nr, nw, hs, he = 0; 234 int bounds, status; 235 u_int sectorsize; 236 237 bounds = getbounds(); 238 dmpcnt = 0; 239 mediasize = 0; 240 status = STATUS_UNKNOWN; 241 242 if (buf == NULL) { 243 buf = malloc(BUFFERSIZE); 244 if (buf == NULL) { 245 syslog(LOG_ERR, "%m"); 246 return; 247 } 248 } 249 250 if (verbose) 251 printf("checking for kernel dump on device %s\n", device); 252 253 fd = open(device, O_RDWR); 254 if (fd < 0) { 255 syslog(LOG_ERR, "%s: %m", device); 256 return; 257 } 258 259 bzero(&dpart, sizeof(dpart)); 260 error = ioctl(fd, DIOCGPART, &dpart); 261 if (error) { 262 syslog(LOG_ERR, 263 "couldn't find media and/or sector size of %s: %m", device); 264 goto closefd; 265 } 266 mediasize = dpart.media_size; 267 sectorsize = dpart.media_blksize; 268 269 if (verbose) { 270 printf("mediasize = %lld\n", (long long)mediasize); 271 printf("sectorsize = %u\n", sectorsize); 272 } 273 274 lasthd = mediasize - sectorsize; 275 lseek(fd, lasthd, SEEK_SET); 276 error = read(fd, &kdhl, sizeof kdhl); 277 if (error != sizeof kdhl) { 278 syslog(LOG_ERR, 279 "error reading last dump header at offset %lld in %s: %m", 280 (long long)lasthd, device); 281 goto closefd; 282 } 283 if (memcmp(kdhl.magic, KERNELDUMPMAGIC, sizeof kdhl.magic)) { 284 if (verbose) 285 printf("magic mismatch on last dump header on %s\n", 286 device); 287 288 status = STATUS_BAD; 289 if (force == 0) 290 goto closefd; 291 292 if (memcmp(kdhl.magic, KERNELDUMPMAGIC_CLEARED, 293 sizeof kdhl.magic) == 0) { 294 if (verbose) 295 printf("forcing magic on %s\n", device); 296 memcpy(kdhl.magic, KERNELDUMPMAGIC, 297 sizeof kdhl.magic); 298 } else { 299 syslog(LOG_ERR, "unable to force dump - bad magic"); 300 goto closefd; 301 } 302 } 303 if (dtoh32(kdhl.version) != KERNELDUMPVERSION) { 304 syslog(LOG_ERR, 305 "unknown version (%d) in last dump header on %s", 306 dtoh32(kdhl.version), device); 307 308 status = STATUS_BAD; 309 if (force == 0) 310 goto closefd; 311 } 312 313 nfound++; 314 if (clear) 315 goto nuke; 316 317 if (kerneldump_parity(&kdhl)) { 318 syslog(LOG_ERR, 319 "parity error on last dump header on %s", device); 320 nerr++; 321 status = STATUS_BAD; 322 if (force == 0) 323 goto closefd; 324 } 325 dumpsize = dtoh64(kdhl.dumplength); 326 firsthd = lasthd - dumpsize - sizeof kdhf; 327 lseek(fd, firsthd, SEEK_SET); 328 error = read(fd, &kdhf, sizeof kdhf); 329 if (error != sizeof kdhf) { 330 syslog(LOG_ERR, 331 "error reading first dump header at offset %lld in %s: %m", 332 (long long)firsthd, device); 333 nerr++; 334 goto closefd; 335 } 336 337 if (verbose >= 2) { 338 printf("First dump headers:\n"); 339 printheader(stdout, &kdhf, device, bounds, -1); 340 341 printf("\nLast dump headers:\n"); 342 printheader(stdout, &kdhl, device, bounds, -1); 343 printf("\n"); 344 } 345 346 if (memcmp(&kdhl, &kdhf, sizeof kdhl)) { 347 syslog(LOG_ERR, 348 "first and last dump headers disagree on %s", device); 349 nerr++; 350 status = STATUS_BAD; 351 if (force == 0) 352 goto closefd; 353 } else { 354 status = STATUS_GOOD; 355 } 356 357 if (checkfor) { 358 printf("A dump exists on %s\n", device); 359 close(fd); 360 exit(0); 361 } 362 363 if (kdhl.panicstring[0]) 364 syslog(LOG_ALERT, "reboot after panic: %s", kdhl.panicstring); 365 else 366 syslog(LOG_ALERT, "reboot"); 367 368 if (verbose) 369 printf("Checking for available free space\n"); 370 if (!check_space(savedir, dumpsize)) { 371 nerr++; 372 goto closefd; 373 } 374 375 writebounds(bounds + 1); 376 377 /* 378 * Write kernel file. 379 */ 380 fdkernin = open(getbootfile(), O_RDONLY, 0); 381 if (fdkernin < 0) { 382 syslog(LOG_ERR, "%s: %m", getbootfile()); 383 } 384 385 if (compress) { 386 sprintf(buf, "kern.%d.gz", bounds); 387 fpkern = zopen(buf, "w"); 388 } else { 389 sprintf(buf, "kern.%d", bounds); 390 fpkern = fopen(buf, "w"); 391 } 392 if (fpkern == NULL) { 393 syslog(LOG_ERR, "%s: %m", buf); 394 close(fdkernin); 395 } 396 397 syslog(LOG_NOTICE, "writing %skernel to %s", 398 compress ? "compressed " : "", buf); 399 400 while ((nr = read(fdkernin, buf, BUFFERSIZE)) > 0) { 401 nw = fwrite(buf, 1, nr, fpkern); 402 if (nw != nr) { 403 syslog(LOG_ERR, "kern.%d: %m", bounds); 404 syslog(LOG_WARNING, 405 "WARNING: kernel may be incomplete"); 406 exit(1); 407 } 408 } 409 if (nr < 0) { 410 syslog(LOG_ERR, "%s: %m", getbootfile()); 411 syslog(LOG_WARNING, 412 "WARNING: kernel may be incomplete"); 413 exit(1); 414 } 415 fclose(fpkern); 416 close(fdkernin); 417 418 419 sprintf(buf, "info.%d", bounds); 420 421 /* 422 * Create or overwrite any existing dump header files. 423 */ 424 fdinfo = open(buf, O_WRONLY | O_CREAT | O_TRUNC, 0600); 425 if (fdinfo < 0) { 426 syslog(LOG_ERR, "%s: %m", buf); 427 nerr++; 428 goto closefd; 429 } 430 oumask = umask(S_IRWXG|S_IRWXO); /* Restrict access to the core file.*/ 431 if (compress) { 432 sprintf(buf, "vmcore.%d.gz", bounds); 433 fp = zopen(buf, "w"); 434 } else { 435 sprintf(buf, "vmcore.%d", bounds); 436 fp = fopen(buf, "w"); 437 } 438 if (fp == NULL) { 439 syslog(LOG_ERR, "%s: %m", buf); 440 close(fdinfo); 441 nerr++; 442 goto closefd; 443 } 444 (void)umask(oumask); 445 446 info = fdopen(fdinfo, "w"); 447 448 if (info == NULL) { 449 syslog(LOG_ERR, "fdopen failed: %m"); 450 nerr++; 451 goto closefd; 452 } 453 454 if (verbose) 455 printheader(stdout, &kdhl, device, bounds, status); 456 457 printheader(info, &kdhl, device, bounds, status); 458 fclose(info); 459 460 syslog(LOG_NOTICE, "writing %score to %s", 461 compress ? "compressed " : "", buf); 462 463 while (dumpsize > 0) { 464 wl = BUFFERSIZE; 465 if (wl > dumpsize) 466 wl = dumpsize; 467 nr = read(fd, buf, wl); 468 if (nr != wl) { 469 if (nr == 0) 470 syslog(LOG_WARNING, 471 "WARNING: EOF on dump device"); 472 else 473 syslog(LOG_ERR, "read error on %s: %m", device); 474 nerr++; 475 goto closeall; 476 } 477 if (compress) { 478 nw = fwrite(buf, 1, wl, fp); 479 } else { 480 for (nw = 0; nw < nr; nw = he) { 481 /* find a contiguous block of zeroes */ 482 for (hs = nw; hs < nr; hs += BLOCKSIZE) { 483 for (he = hs; he < nr && buf[he] == 0; 484 ++he) 485 /* nothing */ ; 486 /* is the hole long enough to matter? */ 487 if (he >= hs + BLOCKSIZE) 488 break; 489 } 490 491 /* back down to a block boundary */ 492 he &= BLOCKMASK; 493 494 /* 495 * 1) Don't go beyond the end of the buffer. 496 * 2) If the end of the buffer is less than 497 * BLOCKSIZE bytes away, we're at the end 498 * of the file, so just grab what's left. 499 */ 500 if (hs + BLOCKSIZE > nr) 501 hs = he = nr; 502 503 /* 504 * At this point, we have a partial ordering: 505 * nw <= hs <= he <= nr 506 * If hs > nw, buf[nw..hs] contains non-zero data. 507 * If he > hs, buf[hs..he] is all zeroes. 508 */ 509 if (hs > nw) 510 if (fwrite(buf + nw, hs - nw, 1, fp) 511 != 1) 512 break; 513 if (he > hs) 514 if (fseeko(fp, he - hs, SEEK_CUR) == -1) 515 break; 516 } 517 } 518 if (nw != wl) { 519 syslog(LOG_ERR, 520 "write error on vmcore.%d file: %m", bounds); 521 syslog(LOG_WARNING, 522 "WARNING: vmcore may be incomplete"); 523 nerr++; 524 goto closeall; 525 } 526 if (verbose) { 527 dmpcnt += wl; 528 printf("%llu\r", (unsigned long long)dmpcnt); 529 fflush(stdout); 530 } 531 dumpsize -= wl; 532 } 533 if (verbose) 534 printf("\n"); 535 536 if (fclose(fp) < 0) { 537 syslog(LOG_ERR, "error on vmcore.%d: %m", bounds); 538 nerr++; 539 goto closeall; 540 } 541 nsaved++; 542 543 if (verbose) 544 printf("dump saved\n"); 545 546 nuke: 547 if (clear || !keep) { 548 if (verbose) 549 printf("clearing dump header\n"); 550 memcpy(kdhl.magic, KERNELDUMPMAGIC_CLEARED, sizeof kdhl.magic); 551 lseek(fd, lasthd, SEEK_SET); 552 error = write(fd, &kdhl, sizeof kdhl); 553 if (error != sizeof kdhl) 554 syslog(LOG_ERR, 555 "error while clearing the dump header: %m"); 556 } 557 close(fd); 558 return; 559 560 closeall: 561 fclose(fp); 562 563 closefd: 564 close(fd); 565 } 566 567 static void 568 usage(void) 569 { 570 fprintf(stderr, "%s\n%s\n%s\n", 571 "usage: savecore -c", 572 " savecore -C [-v] [directory device]", 573 " savecore [-fkvz] [directory [device ...]]"); 574 exit (1); 575 } 576 577 int 578 main(int argc, char **argv) 579 { 580 const char *savedir = "."; 581 struct fstab *fsp; 582 int i, ch, error; 583 584 checkfor = compress = clear = force = keep = verbose = 0; 585 nfound = nsaved = nerr = 0; 586 587 openlog("savecore", LOG_PERROR, LOG_DAEMON); 588 589 while ((ch = getopt(argc, argv, "Ccfkvz")) != -1) 590 switch(ch) { 591 case 'C': 592 checkfor = 1; 593 break; 594 case 'c': 595 clear = 1; 596 break; 597 case 'k': 598 keep = 1; 599 break; 600 case 'v': 601 verbose++; 602 break; 603 case 'f': 604 force = 1; 605 break; 606 case 'z': 607 compress = 1; 608 break; 609 case '?': 610 default: 611 usage(); 612 } 613 if (checkfor && (clear || force || keep)) 614 usage(); 615 argc -= optind; 616 argv += optind; 617 if (argc >= 1) { 618 error = chdir(argv[0]); 619 if (error) { 620 syslog(LOG_ERR, "chdir(%s): %m", argv[0]); 621 exit(1); 622 } 623 savedir = argv[0]; 624 argc--; 625 argv++; 626 } 627 if (argc == 0) { 628 for (;;) { 629 fsp = getfsent(); 630 if (fsp == NULL) 631 break; 632 if (strcmp(fsp->fs_vfstype, "swap") && 633 strcmp(fsp->fs_vfstype, "dump")) 634 continue; 635 DoFile(savedir, fsp->fs_spec); 636 } 637 } else { 638 for (i = 0; i < argc; i++) 639 DoFile(savedir, argv[i]); 640 } 641 642 /* Emit minimal output. */ 643 if (nfound == 0) { 644 if (checkfor) { 645 printf("No dump exists\n"); 646 exit(1); 647 } 648 syslog(LOG_WARNING, "no dumps found"); 649 } 650 else if (nsaved == 0) { 651 if (nerr != 0) 652 syslog(LOG_WARNING, "unsaved dumps found but not saved"); 653 else 654 syslog(LOG_WARNING, "no unsaved dumps found"); 655 } 656 657 return (0); 658 } 659