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 goto newfile; 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 goto newfile; 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"); 161 162 newfile: 163 164 if ((fp = fopen("bounds", "w")) == NULL) { 165 syslog(LOG_WARNING, "unable to write to bounds file: %m"); 166 goto done; 167 } 168 169 if (verbose) 170 printf("bounds number: %d\n", ret); 171 172 fprintf(fp, "%d\n", (ret + 1)); 173 fclose(fp); 174 175 done: 176 return (ret); 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 kerneldumpheader kdhf, kdhl; 231 off_t mediasize, dumpsize, firsthd, lasthd, dmpcnt; 232 FILE *info, *fp; 233 mode_t oumask; 234 int fd, fdinfo, error, wl; 235 int nr, nw, hs, he = 0; 236 int bounds, status; 237 u_int sectorsize; 238 239 bounds = getbounds(); 240 dmpcnt = 0; 241 mediasize = 0; 242 status = STATUS_UNKNOWN; 243 244 if (buf == NULL) { 245 buf = malloc(BUFFERSIZE); 246 if (buf == NULL) { 247 syslog(LOG_ERR, "%m"); 248 return; 249 } 250 } 251 252 if (verbose) 253 printf("checking for kernel dump on device %s\n", device); 254 255 fd = open(device, O_RDWR); 256 if (fd < 0) { 257 syslog(LOG_ERR, "%s: %m", device); 258 return; 259 } 260 261 error = ioctl(fd, DIOCGMEDIASIZE, &mediasize); 262 if (!error) 263 error = ioctl(fd, DIOCGSECTORSIZE, §orsize); 264 if (error) { 265 syslog(LOG_ERR, 266 "couldn't find media and/or sector size of %s: %m", device); 267 goto closefd; 268 } 269 270 if (verbose) { 271 printf("mediasize = %lld\n", (long long)mediasize); 272 printf("sectorsize = %u\n", sectorsize); 273 } 274 275 lasthd = mediasize - sectorsize; 276 lseek(fd, lasthd, SEEK_SET); 277 error = read(fd, &kdhl, sizeof kdhl); 278 if (error != sizeof kdhl) { 279 syslog(LOG_ERR, 280 "error reading last dump header at offset %lld in %s: %m", 281 (long long)lasthd, device); 282 goto closefd; 283 } 284 if (memcmp(kdhl.magic, KERNELDUMPMAGIC, sizeof kdhl.magic)) { 285 if (verbose) 286 printf("magic mismatch on last dump header on %s\n", 287 device); 288 289 status = STATUS_BAD; 290 if (force == 0) 291 goto closefd; 292 293 if (memcmp(kdhl.magic, KERNELDUMPMAGIC_CLEARED, 294 sizeof kdhl.magic) == 0) { 295 if (verbose) 296 printf("forcing magic on %s\n", device); 297 memcpy(kdhl.magic, KERNELDUMPMAGIC, 298 sizeof kdhl.magic); 299 } else { 300 syslog(LOG_ERR, "unable to force dump - bad magic"); 301 goto closefd; 302 } 303 } 304 if (dtoh32(kdhl.version) != KERNELDUMPVERSION) { 305 syslog(LOG_ERR, 306 "unknown version (%d) in last dump header on %s", 307 dtoh32(kdhl.version), device); 308 309 status = STATUS_BAD; 310 if (force == 0) 311 goto closefd; 312 } 313 314 nfound++; 315 if (clear) 316 goto nuke; 317 318 if (kerneldump_parity(&kdhl)) { 319 syslog(LOG_ERR, 320 "parity error on last dump header on %s", device); 321 nerr++; 322 status = STATUS_BAD; 323 if (force == 0) 324 goto closefd; 325 } 326 dumpsize = dtoh64(kdhl.dumplength); 327 firsthd = lasthd - dumpsize - sizeof kdhf; 328 lseek(fd, firsthd, SEEK_SET); 329 error = read(fd, &kdhf, sizeof kdhf); 330 if (error != sizeof kdhf) { 331 syslog(LOG_ERR, 332 "error reading first dump header at offset %lld in %s: %m", 333 (long long)firsthd, device); 334 nerr++; 335 goto closefd; 336 } 337 338 if (verbose >= 2) { 339 printf("First dump headers:\n"); 340 printheader(stdout, &kdhf, device, bounds, -1); 341 342 printf("\nLast dump headers:\n"); 343 printheader(stdout, &kdhl, device, bounds, -1); 344 printf("\n"); 345 } 346 347 if (memcmp(&kdhl, &kdhf, sizeof kdhl)) { 348 syslog(LOG_ERR, 349 "first and last dump headers disagree on %s", device); 350 nerr++; 351 status = STATUS_BAD; 352 if (force == 0) 353 goto closefd; 354 } else { 355 status = STATUS_GOOD; 356 } 357 358 if (checkfor) { 359 printf("A dump exists on %s\n", device); 360 close(fd); 361 exit(0); 362 } 363 364 if (kdhl.panicstring[0]) 365 syslog(LOG_ALERT, "reboot after panic: %s", kdhl.panicstring); 366 else 367 syslog(LOG_ALERT, "reboot"); 368 369 if (verbose) 370 printf("Checking for available free space\n"); 371 if (!check_space(savedir, dumpsize)) { 372 nerr++; 373 goto closefd; 374 } 375 376 sprintf(buf, "info.%d", bounds); 377 378 /* 379 * Create or overwrite any existing dump header files. 380 */ 381 fdinfo = open(buf, O_WRONLY | O_CREAT | O_TRUNC, 0600); 382 if (fdinfo < 0) { 383 syslog(LOG_ERR, "%s: %m", buf); 384 nerr++; 385 goto closefd; 386 } 387 oumask = umask(S_IRWXG|S_IRWXO); /* Restrict access to the core file.*/ 388 if (compress) { 389 sprintf(buf, "vmcore.%d.gz", bounds); 390 fp = zopen(buf, "w"); 391 } else { 392 sprintf(buf, "vmcore.%d", bounds); 393 fp = fopen(buf, "w"); 394 } 395 if (fp == NULL) { 396 syslog(LOG_ERR, "%s: %m", buf); 397 close(fdinfo); 398 nerr++; 399 goto closefd; 400 } 401 (void)umask(oumask); 402 403 info = fdopen(fdinfo, "w"); 404 405 if (verbose) 406 printheader(stdout, &kdhl, device, bounds, status); 407 408 printheader(info, &kdhl, device, bounds, status); 409 fclose(info); 410 411 syslog(LOG_NOTICE, "writing %score to %s", 412 compress ? "compressed " : "", buf); 413 414 while (dumpsize > 0) { 415 wl = BUFFERSIZE; 416 if (wl > dumpsize) 417 wl = dumpsize; 418 nr = read(fd, buf, wl); 419 if (nr != wl) { 420 if (nr == 0) 421 syslog(LOG_WARNING, 422 "WARNING: EOF on dump device"); 423 else 424 syslog(LOG_ERR, "read error on %s: %m", device); 425 nerr++; 426 goto closeall; 427 } 428 if (compress) { 429 nw = fwrite(buf, 1, wl, fp); 430 } else { 431 for (nw = 0; nw < nr; nw = he) { 432 /* find a contiguous block of zeroes */ 433 for (hs = nw; hs < nr; hs += BLOCKSIZE) { 434 for (he = hs; he < nr && buf[he] == 0; 435 ++he) 436 /* nothing */ ; 437 /* is the hole long enough to matter? */ 438 if (he >= hs + BLOCKSIZE) 439 break; 440 } 441 442 /* back down to a block boundary */ 443 he &= BLOCKMASK; 444 445 /* 446 * 1) Don't go beyond the end of the buffer. 447 * 2) If the end of the buffer is less than 448 * BLOCKSIZE bytes away, we're at the end 449 * of the file, so just grab what's left. 450 */ 451 if (hs + BLOCKSIZE > nr) 452 hs = he = nr; 453 454 /* 455 * At this point, we have a partial ordering: 456 * nw <= hs <= he <= nr 457 * If hs > nw, buf[nw..hs] contains non-zero data. 458 * If he > hs, buf[hs..he] is all zeroes. 459 */ 460 if (hs > nw) 461 if (fwrite(buf + nw, hs - nw, 1, fp) 462 != 1) 463 break; 464 if (he > hs) 465 if (fseeko(fp, he - hs, SEEK_CUR) == -1) 466 break; 467 } 468 } 469 if (nw != wl) { 470 syslog(LOG_ERR, 471 "write error on vmcore.%d file: %m", bounds); 472 syslog(LOG_WARNING, 473 "WARNING: vmcore may be incomplete"); 474 nerr++; 475 goto closeall; 476 } 477 if (verbose) { 478 dmpcnt += wl; 479 printf("%llu\r", (unsigned long long)dmpcnt); 480 fflush(stdout); 481 } 482 dumpsize -= wl; 483 } 484 if (verbose) 485 printf("\n"); 486 487 if (fclose(fp) < 0) { 488 syslog(LOG_ERR, "error on vmcore.%d: %m", bounds); 489 nerr++; 490 goto closeall; 491 } 492 nsaved++; 493 494 if (verbose) 495 printf("dump saved\n"); 496 497 nuke: 498 if (clear || !keep) { 499 if (verbose) 500 printf("clearing dump header\n"); 501 memcpy(kdhl.magic, KERNELDUMPMAGIC_CLEARED, sizeof kdhl.magic); 502 lseek(fd, lasthd, SEEK_SET); 503 error = write(fd, &kdhl, sizeof kdhl); 504 if (error != sizeof kdhl) 505 syslog(LOG_ERR, 506 "error while clearing the dump header: %m"); 507 } 508 close(fd); 509 return; 510 511 closeall: 512 fclose(fp); 513 514 closefd: 515 close(fd); 516 } 517 518 static void 519 usage(void) 520 { 521 fprintf(stderr, "%s\n%s\n%s\n", 522 "usage: savecore -c", 523 " savecore -C [-v] [directory device]", 524 " savecore [-fkvz] [directory [device ...]]"); 525 exit (1); 526 } 527 528 int 529 main(int argc, char **argv) 530 { 531 const char *savedir = "."; 532 struct fstab *fsp; 533 int i, ch, error; 534 535 checkfor = compress = clear = force = keep = verbose = 0; 536 nfound = nsaved = nerr = 0; 537 538 openlog("savecore", LOG_PERROR, LOG_DAEMON); 539 540 while ((ch = getopt(argc, argv, "Ccfkvz")) != -1) 541 switch(ch) { 542 case 'C': 543 checkfor = 1; 544 break; 545 case 'c': 546 clear = 1; 547 break; 548 case 'k': 549 keep = 1; 550 break; 551 case 'v': 552 verbose++; 553 break; 554 case 'f': 555 force = 1; 556 break; 557 case 'z': 558 compress = 1; 559 break; 560 case '?': 561 default: 562 usage(); 563 } 564 if (checkfor && (clear || force || keep)) 565 usage(); 566 argc -= optind; 567 argv += optind; 568 if (argc >= 1) { 569 error = chdir(argv[0]); 570 if (error) { 571 syslog(LOG_ERR, "chdir(%s): %m", argv[0]); 572 exit(1); 573 } 574 savedir = argv[0]; 575 argc--; 576 argv++; 577 } 578 if (argc == 0) { 579 for (;;) { 580 fsp = getfsent(); 581 if (fsp == NULL) 582 break; 583 if (strcmp(fsp->fs_vfstype, "swap") && 584 strcmp(fsp->fs_vfstype, "dump")) 585 continue; 586 DoFile(savedir, fsp->fs_spec); 587 } 588 } else { 589 for (i = 0; i < argc; i++) 590 DoFile(savedir, argv[i]); 591 } 592 593 /* Emit minimal output. */ 594 if (nfound == 0) { 595 if (checkfor) { 596 printf("No dump exists\n"); 597 exit(1); 598 } 599 syslog(LOG_WARNING, "no dumps found"); 600 } 601 else if (nsaved == 0) { 602 if (nerr != 0) 603 syslog(LOG_WARNING, "unsaved dumps found but not saved"); 604 else 605 syslog(LOG_WARNING, "no unsaved dumps found"); 606 } 607 608 return (0); 609 } 610