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 syslog(LOG_WARNING, "unable to open bounds file, using 0"); 148 return (ret); 149 } 150 151 if (fgets(buf, sizeof buf, fp) == NULL) { 152 syslog(LOG_WARNING, "unable to read from bounds, using 0"); 153 fclose(fp); 154 return (ret); 155 } 156 157 errno = 0; 158 ret = (int)strtol(buf, NULL, 10); 159 if (ret == 0 && (errno == EINVAL || errno == ERANGE)) 160 syslog(LOG_WARNING, "invalid value found in bounds, using 0"); 161 return (ret); 162 } 163 164 static void 165 writebounds(int bounds) { 166 FILE *fp; 167 168 if ((fp = fopen("bounds", "w")) == NULL) { 169 syslog(LOG_WARNING, "unable to write to bounds file: %m"); 170 return; 171 } 172 173 if (verbose) 174 printf("bounds number: %d\n", bounds); 175 176 fprintf(fp, "%d\n", bounds); 177 fclose(fp); 178 } 179 180 /* 181 * Check that sufficient space is available on the disk that holds the 182 * save directory. 183 */ 184 static int 185 check_space(const char *savedir, off_t dumpsize) 186 { 187 FILE *fp; 188 off_t minfree, spacefree, totfree, needed; 189 struct statfs fsbuf; 190 char buf[100], path[MAXPATHLEN]; 191 192 if (statfs(savedir, &fsbuf) < 0) { 193 syslog(LOG_ERR, "%s: %m", savedir); 194 exit(1); 195 } 196 spacefree = ((off_t) fsbuf.f_bavail * fsbuf.f_bsize) / 1024; 197 totfree = ((off_t) fsbuf.f_bfree * fsbuf.f_bsize) / 1024; 198 199 (void)snprintf(path, sizeof(path), "%s/minfree", savedir); 200 if ((fp = fopen(path, "r")) == NULL) 201 minfree = 0; 202 else { 203 if (fgets(buf, sizeof(buf), fp) == NULL) 204 minfree = 0; 205 else 206 minfree = atoi(buf); 207 (void)fclose(fp); 208 } 209 210 needed = dumpsize / 1024 + 2; /* 2 for info file */ 211 if (((minfree > 0) ? spacefree : totfree) - needed < minfree) { 212 syslog(LOG_WARNING, 213 "no dump, not enough free space on device (%lld available, need %lld)", 214 (long long)(minfree > 0 ? spacefree : totfree), 215 (long long)needed); 216 return (0); 217 } 218 if (spacefree - needed < 0) 219 syslog(LOG_WARNING, 220 "dump performed, but free space threshold crossed"); 221 return (1); 222 } 223 224 #define BLOCKSIZE (1<<12) 225 #define BLOCKMASK (~(BLOCKSIZE-1)) 226 227 static void 228 DoFile(const char *savedir, const char *device) 229 { 230 static char *buf = NULL; 231 struct kerneldumpheader kdhf, kdhl; 232 off_t mediasize, dumpsize, firsthd, lasthd, dmpcnt; 233 FILE *info, *fp; 234 mode_t oumask; 235 int fd, fdinfo, 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 error = ioctl(fd, DIOCGMEDIASIZE, &mediasize); 263 if (!error) 264 error = ioctl(fd, DIOCGSECTORSIZE, §orsize); 265 if (error) { 266 syslog(LOG_ERR, 267 "couldn't find media and/or sector size of %s: %m", device); 268 goto closefd; 269 } 270 271 if (verbose) { 272 printf("mediasize = %lld\n", (long long)mediasize); 273 printf("sectorsize = %u\n", sectorsize); 274 } 275 276 lasthd = mediasize - sectorsize; 277 lseek(fd, lasthd, SEEK_SET); 278 error = read(fd, &kdhl, sizeof kdhl); 279 if (error != sizeof kdhl) { 280 syslog(LOG_ERR, 281 "error reading last dump header at offset %lld in %s: %m", 282 (long long)lasthd, device); 283 goto closefd; 284 } 285 if (memcmp(kdhl.magic, KERNELDUMPMAGIC, sizeof kdhl.magic)) { 286 if (verbose) 287 printf("magic mismatch on last dump header on %s\n", 288 device); 289 290 status = STATUS_BAD; 291 if (force == 0) 292 goto closefd; 293 294 if (memcmp(kdhl.magic, KERNELDUMPMAGIC_CLEARED, 295 sizeof kdhl.magic) == 0) { 296 if (verbose) 297 printf("forcing magic on %s\n", device); 298 memcpy(kdhl.magic, KERNELDUMPMAGIC, 299 sizeof kdhl.magic); 300 } else { 301 syslog(LOG_ERR, "unable to force dump - bad magic"); 302 goto closefd; 303 } 304 } 305 if (dtoh32(kdhl.version) != KERNELDUMPVERSION) { 306 syslog(LOG_ERR, 307 "unknown version (%d) in last dump header on %s", 308 dtoh32(kdhl.version), device); 309 310 status = STATUS_BAD; 311 if (force == 0) 312 goto closefd; 313 } 314 315 nfound++; 316 if (clear) 317 goto nuke; 318 319 if (kerneldump_parity(&kdhl)) { 320 syslog(LOG_ERR, 321 "parity error on last dump header on %s", device); 322 nerr++; 323 status = STATUS_BAD; 324 if (force == 0) 325 goto closefd; 326 } 327 dumpsize = dtoh64(kdhl.dumplength); 328 firsthd = lasthd - dumpsize - sizeof kdhf; 329 lseek(fd, firsthd, SEEK_SET); 330 error = read(fd, &kdhf, sizeof kdhf); 331 if (error != sizeof kdhf) { 332 syslog(LOG_ERR, 333 "error reading first dump header at offset %lld in %s: %m", 334 (long long)firsthd, device); 335 nerr++; 336 goto closefd; 337 } 338 339 if (verbose >= 2) { 340 printf("First dump headers:\n"); 341 printheader(stdout, &kdhf, device, bounds, -1); 342 343 printf("\nLast dump headers:\n"); 344 printheader(stdout, &kdhl, device, bounds, -1); 345 printf("\n"); 346 } 347 348 if (memcmp(&kdhl, &kdhf, sizeof kdhl)) { 349 syslog(LOG_ERR, 350 "first and last dump headers disagree on %s", device); 351 nerr++; 352 status = STATUS_BAD; 353 if (force == 0) 354 goto closefd; 355 } else { 356 status = STATUS_GOOD; 357 } 358 359 if (checkfor) { 360 printf("A dump exists on %s\n", device); 361 close(fd); 362 exit(0); 363 } 364 365 if (kdhl.panicstring[0]) 366 syslog(LOG_ALERT, "reboot after panic: %s", kdhl.panicstring); 367 else 368 syslog(LOG_ALERT, "reboot"); 369 370 if (verbose) 371 printf("Checking for available free space\n"); 372 if (!check_space(savedir, dumpsize)) { 373 nerr++; 374 goto closefd; 375 } 376 377 writebounds(bounds + 1); 378 379 sprintf(buf, "info.%d", bounds); 380 381 /* 382 * Create or overwrite any existing dump header files. 383 */ 384 fdinfo = open(buf, O_WRONLY | O_CREAT | O_TRUNC, 0600); 385 if (fdinfo < 0) { 386 syslog(LOG_ERR, "%s: %m", buf); 387 nerr++; 388 goto closefd; 389 } 390 oumask = umask(S_IRWXG|S_IRWXO); /* Restrict access to the core file.*/ 391 if (compress) { 392 sprintf(buf, "vmcore.%d.gz", bounds); 393 fp = zopen(buf, "w"); 394 } else { 395 sprintf(buf, "vmcore.%d", bounds); 396 fp = fopen(buf, "w"); 397 } 398 if (fp == NULL) { 399 syslog(LOG_ERR, "%s: %m", buf); 400 close(fdinfo); 401 nerr++; 402 goto closefd; 403 } 404 (void)umask(oumask); 405 406 info = fdopen(fdinfo, "w"); 407 408 if (verbose) 409 printheader(stdout, &kdhl, device, bounds, status); 410 411 printheader(info, &kdhl, device, bounds, status); 412 fclose(info); 413 414 syslog(LOG_NOTICE, "writing %score to %s", 415 compress ? "compressed " : "", buf); 416 417 while (dumpsize > 0) { 418 wl = BUFFERSIZE; 419 if (wl > dumpsize) 420 wl = dumpsize; 421 nr = read(fd, buf, wl); 422 if (nr != wl) { 423 if (nr == 0) 424 syslog(LOG_WARNING, 425 "WARNING: EOF on dump device"); 426 else 427 syslog(LOG_ERR, "read error on %s: %m", device); 428 nerr++; 429 goto closeall; 430 } 431 if (compress) { 432 nw = fwrite(buf, 1, wl, fp); 433 } else { 434 for (nw = 0; nw < nr; nw = he) { 435 /* find a contiguous block of zeroes */ 436 for (hs = nw; hs < nr; hs += BLOCKSIZE) { 437 for (he = hs; he < nr && buf[he] == 0; 438 ++he) 439 /* nothing */ ; 440 /* is the hole long enough to matter? */ 441 if (he >= hs + BLOCKSIZE) 442 break; 443 } 444 445 /* back down to a block boundary */ 446 he &= BLOCKMASK; 447 448 /* 449 * 1) Don't go beyond the end of the buffer. 450 * 2) If the end of the buffer is less than 451 * BLOCKSIZE bytes away, we're at the end 452 * of the file, so just grab what's left. 453 */ 454 if (hs + BLOCKSIZE > nr) 455 hs = he = nr; 456 457 /* 458 * At this point, we have a partial ordering: 459 * nw <= hs <= he <= nr 460 * If hs > nw, buf[nw..hs] contains non-zero data. 461 * If he > hs, buf[hs..he] is all zeroes. 462 */ 463 if (hs > nw) 464 if (fwrite(buf + nw, hs - nw, 1, fp) 465 != 1) 466 break; 467 if (he > hs) 468 if (fseeko(fp, he - hs, SEEK_CUR) == -1) 469 break; 470 } 471 } 472 if (nw != wl) { 473 syslog(LOG_ERR, 474 "write error on vmcore.%d file: %m", bounds); 475 syslog(LOG_WARNING, 476 "WARNING: vmcore may be incomplete"); 477 nerr++; 478 goto closeall; 479 } 480 if (verbose) { 481 dmpcnt += wl; 482 printf("%llu\r", (unsigned long long)dmpcnt); 483 fflush(stdout); 484 } 485 dumpsize -= wl; 486 } 487 if (verbose) 488 printf("\n"); 489 490 if (fclose(fp) < 0) { 491 syslog(LOG_ERR, "error on vmcore.%d: %m", bounds); 492 nerr++; 493 goto closeall; 494 } 495 nsaved++; 496 497 if (verbose) 498 printf("dump saved\n"); 499 500 nuke: 501 if (clear || !keep) { 502 if (verbose) 503 printf("clearing dump header\n"); 504 memcpy(kdhl.magic, KERNELDUMPMAGIC_CLEARED, sizeof kdhl.magic); 505 lseek(fd, lasthd, SEEK_SET); 506 error = write(fd, &kdhl, sizeof kdhl); 507 if (error != sizeof kdhl) 508 syslog(LOG_ERR, 509 "error while clearing the dump header: %m"); 510 } 511 close(fd); 512 return; 513 514 closeall: 515 fclose(fp); 516 517 closefd: 518 close(fd); 519 } 520 521 static void 522 usage(void) 523 { 524 fprintf(stderr, "%s\n%s\n%s\n", 525 "usage: savecore -c", 526 " savecore -C [-v] [directory device]", 527 " savecore [-fkvz] [directory [device ...]]"); 528 exit (1); 529 } 530 531 int 532 main(int argc, char **argv) 533 { 534 const char *savedir = "."; 535 struct fstab *fsp; 536 int i, ch, error; 537 538 checkfor = compress = clear = force = keep = verbose = 0; 539 nfound = nsaved = nerr = 0; 540 541 openlog("savecore", LOG_PERROR, LOG_DAEMON); 542 543 while ((ch = getopt(argc, argv, "Ccfkvz")) != -1) 544 switch(ch) { 545 case 'C': 546 checkfor = 1; 547 break; 548 case 'c': 549 clear = 1; 550 break; 551 case 'k': 552 keep = 1; 553 break; 554 case 'v': 555 verbose++; 556 break; 557 case 'f': 558 force = 1; 559 break; 560 case 'z': 561 compress = 1; 562 break; 563 case '?': 564 default: 565 usage(); 566 } 567 if (checkfor && (clear || force || keep)) 568 usage(); 569 argc -= optind; 570 argv += optind; 571 if (argc >= 1) { 572 error = chdir(argv[0]); 573 if (error) { 574 syslog(LOG_ERR, "chdir(%s): %m", argv[0]); 575 exit(1); 576 } 577 savedir = argv[0]; 578 argc--; 579 argv++; 580 } 581 if (argc == 0) { 582 for (;;) { 583 fsp = getfsent(); 584 if (fsp == NULL) 585 break; 586 if (strcmp(fsp->fs_vfstype, "swap") && 587 strcmp(fsp->fs_vfstype, "dump")) 588 continue; 589 DoFile(savedir, fsp->fs_spec); 590 } 591 } else { 592 for (i = 0; i < argc; i++) 593 DoFile(savedir, argv[i]); 594 } 595 596 /* Emit minimal output. */ 597 if (nfound == 0) { 598 if (checkfor) { 599 printf("No dump exists\n"); 600 exit(1); 601 } 602 syslog(LOG_WARNING, "no dumps found"); 603 } 604 else if (nsaved == 0) { 605 if (nerr != 0) 606 syslog(LOG_WARNING, "unsaved dumps found but not saved"); 607 else 608 syslog(LOG_WARNING, "no unsaved dumps found"); 609 } 610 611 return (0); 612 } 613