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 __FBSDID("$FreeBSD$"); 69 70 #include <sys/param.h> 71 #include <sys/disk.h> 72 #include <sys/kerneldump.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", 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 kerneldumpheader kdhf, kdhl; 233 off_t mediasize, dumpsize, firsthd, lasthd, dmpcnt; 234 FILE *info, *fp; 235 mode_t oumask; 236 int fd, fdinfo, error, wl; 237 int nr, nw, hs, he = 0; 238 int bounds, status; 239 u_int sectorsize; 240 241 bounds = getbounds(); 242 dmpcnt = 0; 243 mediasize = 0; 244 status = STATUS_UNKNOWN; 245 246 if (buf == NULL) { 247 buf = malloc(BUFFERSIZE); 248 if (buf == NULL) { 249 syslog(LOG_ERR, "%m"); 250 return; 251 } 252 } 253 254 if (verbose) 255 printf("checking for kernel dump on device %s\n", device); 256 257 fd = open(device, O_RDWR); 258 if (fd < 0) { 259 syslog(LOG_ERR, "%s: %m", device); 260 return; 261 } 262 263 error = ioctl(fd, DIOCGMEDIASIZE, &mediasize); 264 if (!error) 265 error = ioctl(fd, DIOCGSECTORSIZE, §orsize); 266 if (error) { 267 syslog(LOG_ERR, 268 "couldn't find media and/or sector size of %s: %m", device); 269 goto closefd; 270 } 271 272 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 sprintf(buf, "info.%d", bounds); 381 382 /* 383 * Create or overwrite any existing dump header files. 384 */ 385 fdinfo = open(buf, O_WRONLY | O_CREAT | O_TRUNC, 0600); 386 if (fdinfo < 0) { 387 syslog(LOG_ERR, "%s: %m", buf); 388 nerr++; 389 goto closefd; 390 } 391 oumask = umask(S_IRWXG|S_IRWXO); /* Restrict access to the core file.*/ 392 if (compress) { 393 sprintf(buf, "vmcore.%d.gz", bounds); 394 fp = zopen(buf, "w"); 395 } else { 396 sprintf(buf, "vmcore.%d", bounds); 397 fp = fopen(buf, "w"); 398 } 399 if (fp == NULL) { 400 syslog(LOG_ERR, "%s: %m", buf); 401 close(fdinfo); 402 nerr++; 403 goto closefd; 404 } 405 (void)umask(oumask); 406 407 info = fdopen(fdinfo, "w"); 408 409 if (verbose) 410 printheader(stdout, &kdhl, device, bounds, status); 411 412 printheader(info, &kdhl, device, bounds, status); 413 fclose(info); 414 415 syslog(LOG_NOTICE, "writing %score to %s", 416 compress ? "compressed " : "", buf); 417 418 while (dumpsize > 0) { 419 wl = BUFFERSIZE; 420 if (wl > dumpsize) 421 wl = dumpsize; 422 nr = read(fd, buf, wl); 423 if (nr != wl) { 424 if (nr == 0) 425 syslog(LOG_WARNING, 426 "WARNING: EOF on dump device"); 427 else 428 syslog(LOG_ERR, "read error on %s: %m", device); 429 nerr++; 430 goto closeall; 431 } 432 if (compress) { 433 nw = fwrite(buf, 1, wl, fp); 434 } else { 435 for (nw = 0; nw < nr; nw = he) { 436 /* find a contiguous block of zeroes */ 437 for (hs = nw; hs < nr; hs += BLOCKSIZE) { 438 for (he = hs; he < nr && buf[he] == 0; 439 ++he) 440 /* nothing */ ; 441 /* is the hole long enough to matter? */ 442 if (he >= hs + BLOCKSIZE) 443 break; 444 } 445 446 /* back down to a block boundary */ 447 he &= BLOCKMASK; 448 449 /* 450 * 1) Don't go beyond the end of the buffer. 451 * 2) If the end of the buffer is less than 452 * BLOCKSIZE bytes away, we're at the end 453 * of the file, so just grab what's left. 454 */ 455 if (hs + BLOCKSIZE > nr) 456 hs = he = nr; 457 458 /* 459 * At this point, we have a partial ordering: 460 * nw <= hs <= he <= nr 461 * If hs > nw, buf[nw..hs] contains non-zero data. 462 * If he > hs, buf[hs..he] is all zeroes. 463 */ 464 if (hs > nw) 465 if (fwrite(buf + nw, hs - nw, 1, fp) 466 != 1) 467 break; 468 if (he > hs) 469 if (fseeko(fp, he - hs, SEEK_CUR) == -1) 470 break; 471 } 472 } 473 if (nw != wl) { 474 syslog(LOG_ERR, 475 "write error on vmcore.%d file: %m", bounds); 476 syslog(LOG_WARNING, 477 "WARNING: vmcore may be incomplete"); 478 nerr++; 479 goto closeall; 480 } 481 if (verbose) { 482 dmpcnt += wl; 483 printf("%llu\r", (unsigned long long)dmpcnt); 484 fflush(stdout); 485 } 486 dumpsize -= wl; 487 } 488 if (verbose) 489 printf("\n"); 490 491 if (fclose(fp) < 0) { 492 syslog(LOG_ERR, "error on vmcore.%d: %m", bounds); 493 nerr++; 494 goto closeall; 495 } 496 nsaved++; 497 498 if (verbose) 499 printf("dump saved\n"); 500 501 nuke: 502 if (clear || !keep) { 503 if (verbose) 504 printf("clearing dump header\n"); 505 memcpy(kdhl.magic, KERNELDUMPMAGIC_CLEARED, sizeof kdhl.magic); 506 lseek(fd, lasthd, SEEK_SET); 507 error = write(fd, &kdhl, sizeof kdhl); 508 if (error != sizeof kdhl) 509 syslog(LOG_ERR, 510 "error while clearing the dump header: %m"); 511 } 512 close(fd); 513 return; 514 515 closeall: 516 fclose(fp); 517 518 closefd: 519 close(fd); 520 } 521 522 static void 523 usage(void) 524 { 525 fprintf(stderr, "%s\n%s\n%s\n", 526 "usage: savecore -c", 527 " savecore -C [-v] [directory device]", 528 " savecore [-fkvz] [directory [device ...]]"); 529 exit (1); 530 } 531 532 int 533 main(int argc, char **argv) 534 { 535 const char *savedir = "."; 536 struct fstab *fsp; 537 int i, ch, error; 538 539 checkfor = compress = clear = force = keep = verbose = 0; 540 nfound = nsaved = nerr = 0; 541 542 openlog("savecore", LOG_PERROR, LOG_DAEMON); 543 544 while ((ch = getopt(argc, argv, "Ccfkvz")) != -1) 545 switch(ch) { 546 case 'C': 547 checkfor = 1; 548 break; 549 case 'c': 550 clear = 1; 551 break; 552 case 'k': 553 keep = 1; 554 break; 555 case 'v': 556 verbose++; 557 break; 558 case 'f': 559 force = 1; 560 break; 561 case 'z': 562 compress = 1; 563 break; 564 case '?': 565 default: 566 usage(); 567 } 568 if (checkfor && (clear || force || keep)) 569 usage(); 570 argc -= optind; 571 argv += optind; 572 if (argc >= 1) { 573 error = chdir(argv[0]); 574 if (error) { 575 syslog(LOG_ERR, "chdir(%s): %m", argv[0]); 576 exit(1); 577 } 578 savedir = argv[0]; 579 argc--; 580 argv++; 581 } 582 if (argc == 0) { 583 for (;;) { 584 fsp = getfsent(); 585 if (fsp == NULL) 586 break; 587 if (strcmp(fsp->fs_vfstype, "swap") && 588 strcmp(fsp->fs_vfstype, "dump")) 589 continue; 590 DoFile(savedir, fsp->fs_spec); 591 } 592 } else { 593 for (i = 0; i < argc; i++) 594 DoFile(savedir, argv[i]); 595 } 596 597 /* Emit minimal output. */ 598 if (nfound == 0) { 599 if (checkfor) { 600 printf("No dump exists\n"); 601 exit(1); 602 } 603 syslog(LOG_WARNING, "no dumps found"); 604 } 605 else if (nsaved == 0) { 606 if (nerr != 0) 607 syslog(LOG_WARNING, "unsaved dumps found but not saved"); 608 else 609 syslog(LOG_WARNING, "no unsaved dumps found"); 610 } 611 612 return (0); 613 } 614