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 int compress, clear, force, keep, verbose; /* flags */ 89 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) 96 { 97 uint64_t dumplen; 98 time_t t; 99 100 fprintf(f, "Good dump found on device %s\n", device); 101 fprintf(f, " Architecture: %s\n", h->architecture); 102 fprintf(f, " Architecture version: %d\n", 103 dtoh32(h->architectureversion)); 104 dumplen = dtoh64(h->dumplength); 105 fprintf(f, " Dump length: %lldB (%lld MB)\n", (long long)dumplen, 106 (long long)(dumplen >> 20)); 107 fprintf(f, " Blocksize: %d\n", dtoh32(h->blocksize)); 108 t = dtoh64(h->dumptime); 109 fprintf(f, " Dumptime: %s", ctime(&t)); 110 fprintf(f, " Hostname: %s\n", h->hostname); 111 fprintf(f, " Versionstring: %s", h->versionstring); 112 fprintf(f, " Panicstring: %s\n", h->panicstring); 113 fprintf(f, " Bounds: %d\n", bounds); 114 fflush(f); 115 } 116 117 static int 118 getbounds(void) { 119 FILE *fp; 120 char buf[6]; 121 int ret; 122 123 ret = 0; 124 125 if ((fp = fopen("bounds", "r")) == NULL) { 126 syslog(LOG_WARNING, "unable to open bounds file, using 0"); 127 goto newfile; 128 } 129 130 if (fgets(buf, sizeof buf, fp) == NULL) { 131 syslog(LOG_WARNING, "unable to read from bounds, using 0"); 132 fclose(fp); 133 goto newfile; 134 } 135 136 errno = 0; 137 ret = (int)strtol(buf, NULL, 10); 138 if (ret == 0 && (errno == EINVAL || errno == ERANGE)) 139 syslog(LOG_WARNING, "invalid value found in bounds, using 0"); 140 141 newfile: 142 143 if ((fp = fopen("bounds", "w")) == NULL) { 144 syslog(LOG_WARNING, "unable to write to bounds file: %m"); 145 goto done; 146 } 147 148 if (verbose) 149 printf("bounds number: %d\n", ret); 150 151 fprintf(fp, "%d\n", (ret + 1)); 152 fclose(fp); 153 154 done: 155 return (ret); 156 } 157 158 /* 159 * Check that sufficient space is available on the disk that holds the 160 * save directory. 161 */ 162 static int 163 check_space(char *savedir, off_t dumpsize) 164 { 165 FILE *fp; 166 off_t minfree, spacefree, totfree, needed; 167 struct statfs fsbuf; 168 char buf[100], path[MAXPATHLEN]; 169 170 if (statfs(savedir, &fsbuf) < 0) { 171 syslog(LOG_ERR, "%s: %m", savedir); 172 exit(1); 173 } 174 spacefree = ((off_t) fsbuf.f_bavail * fsbuf.f_bsize) / 1024; 175 totfree = ((off_t) fsbuf.f_bfree * fsbuf.f_bsize) / 1024; 176 177 (void)snprintf(path, sizeof(path), "%s/minfree", savedir); 178 if ((fp = fopen(path, "r")) == NULL) 179 minfree = 0; 180 else { 181 if (fgets(buf, sizeof(buf), fp) == NULL) 182 minfree = 0; 183 else 184 minfree = atoi(buf); 185 (void)fclose(fp); 186 } 187 188 needed = dumpsize / 1024 + 2; /* 2 for info file */ 189 if (((minfree > 0) ? spacefree : totfree) - needed < minfree) { 190 syslog(LOG_WARNING, 191 "no dump, not enough free space on device (%lld available, need %lld)", 192 (long long)(minfree > 0 ? spacefree : totfree), 193 (long long)needed); 194 return (0); 195 } 196 if (spacefree - needed < 0) 197 syslog(LOG_WARNING, 198 "dump performed, but free space threshold crossed"); 199 return (1); 200 } 201 202 #define BLOCKSIZE (1<<12) 203 #define BLOCKMASK (~(BLOCKSIZE-1)) 204 205 static void 206 DoFile(char *savedir, const char *device) 207 { 208 struct kerneldumpheader kdhf, kdhl; 209 char buf[1024 * 1024]; 210 off_t mediasize, dumpsize, firsthd, lasthd, dmpcnt; 211 FILE *info, *fp; 212 int fd, fdinfo, error, wl; 213 int nr, nw, hs, he; 214 int bounds; 215 u_int sectorsize; 216 mode_t oumask; 217 218 dmpcnt = 0; 219 mediasize = 0; 220 221 if (verbose) 222 printf("checking for kernel dump on device %s\n", device); 223 224 fd = open(device, O_RDWR); 225 if (fd < 0) { 226 syslog(LOG_ERR, "%s: %m", device); 227 return; 228 } 229 error = ioctl(fd, DIOCGMEDIASIZE, &mediasize); 230 if (!error) 231 error = ioctl(fd, DIOCGSECTORSIZE, §orsize); 232 if (error) { 233 syslog(LOG_ERR, 234 "couldn't find media and/or sector size of %s: %m", device); 235 goto closefd; 236 } 237 238 if (verbose) { 239 printf("mediasize = %lld\n", (long long)mediasize); 240 printf("sectorsize = %u\n", sectorsize); 241 } 242 243 lasthd = mediasize - sectorsize; 244 lseek(fd, lasthd, SEEK_SET); 245 error = read(fd, &kdhl, sizeof kdhl); 246 if (error != sizeof kdhl) { 247 syslog(LOG_ERR, 248 "error reading last dump header at offset %lld in %s: %m", 249 (long long)lasthd, device); 250 goto closefd; 251 } 252 if (memcmp(kdhl.magic, KERNELDUMPMAGIC, sizeof kdhl.magic)) { 253 if (verbose) 254 printf("magic mismatch on last dump header on %s\n", 255 device); 256 257 if (force == 0) 258 goto closefd; 259 260 if (memcmp(kdhl.magic, KERNELDUMPMAGIC_CLEARED, 261 sizeof kdhl.magic) == 0) { 262 if (verbose) 263 printf("forcing magic on %s\n", device); 264 memcpy(kdhl.magic, KERNELDUMPMAGIC, 265 sizeof kdhl.magic); 266 } else { 267 syslog(LOG_ERR, "unable to force dump - bad magic"); 268 goto closefd; 269 } 270 } 271 if (dtoh32(kdhl.version) != KERNELDUMPVERSION) { 272 syslog(LOG_ERR, 273 "unknown version (%d) in last dump header on %s", 274 dtoh32(kdhl.version), device); 275 goto closefd; 276 } 277 278 nfound++; 279 if (clear) 280 goto nuke; 281 282 if (kerneldump_parity(&kdhl)) { 283 syslog(LOG_ERR, 284 "parity error on last dump header on %s", device); 285 nerr++; 286 goto closefd; 287 } 288 dumpsize = dtoh64(kdhl.dumplength); 289 firsthd = lasthd - dumpsize - sizeof kdhf; 290 lseek(fd, firsthd, SEEK_SET); 291 error = read(fd, &kdhf, sizeof kdhf); 292 if (error != sizeof kdhf) { 293 syslog(LOG_ERR, 294 "error reading first dump header at offset %lld in %s: %m", 295 (long long)firsthd, device); 296 nerr++; 297 goto closefd; 298 } 299 if (memcmp(&kdhl, &kdhf, sizeof kdhl)) { 300 syslog(LOG_ERR, 301 "first and last dump headers disagree on %s", device); 302 nerr++; 303 goto closefd; 304 } 305 306 if (kdhl.panicstring[0]) 307 syslog(LOG_ALERT, "reboot after panic: %s", kdhl.panicstring); 308 else 309 syslog(LOG_ALERT, "reboot"); 310 311 if (verbose) 312 printf("Checking for available free space\n"); 313 if (!check_space(savedir, dumpsize)) { 314 nerr++; 315 goto closefd; 316 } 317 318 bounds = getbounds(); 319 320 sprintf(buf, "info.%d", bounds); 321 322 /* 323 * Create or overwrite any existing files. 324 */ 325 fdinfo = open(buf, O_WRONLY | O_CREAT | O_TRUNC, 0600); 326 if (fdinfo < 0) { 327 syslog(LOG_ERR, "%s: %m", buf); 328 nerr++; 329 goto closefd; 330 } 331 oumask = umask(S_IRWXG|S_IRWXO); /* Restrict access to the core file.*/ 332 if (compress) { 333 sprintf(buf, "vmcore.%d.gz", bounds); 334 fp = zopen(buf, "w"); 335 } else { 336 sprintf(buf, "vmcore.%d", bounds); 337 fp = fopen(buf, "w"); 338 } 339 if (fp == NULL) { 340 syslog(LOG_ERR, "%s: %m", buf); 341 close(fdinfo); 342 nerr++; 343 goto closefd; 344 } 345 (void)umask(oumask); 346 347 info = fdopen(fdinfo, "w"); 348 349 if (verbose) 350 printheader(stdout, &kdhl, device, bounds); 351 352 printheader(info, &kdhl, device, bounds); 353 fclose(info); 354 355 syslog(LOG_NOTICE, "writing %score to %s", 356 compress ? "compressed " : "", buf); 357 358 while (dumpsize > 0) { 359 wl = sizeof(buf); 360 if (wl > dumpsize) 361 wl = dumpsize; 362 nr = read(fd, buf, wl); 363 if (nr != wl) { 364 if (nr == 0) 365 syslog(LOG_WARNING, 366 "WARNING: EOF on dump device"); 367 else 368 syslog(LOG_ERR, "read error on %s: %m", device); 369 nerr++; 370 goto closeall; 371 } 372 if (compress) { 373 nw = fwrite(buf, 1, wl, fp); 374 } else { 375 for (nw = 0; nw < nr; nw = he) { 376 /* find a contiguous block of zeroes */ 377 for (hs = nw; hs < nr; hs += BLOCKSIZE) { 378 for (he = hs; he < nr && buf[he] == 0; ++he) 379 /* nothing */ ; 380 /* is the hole long enough to matter? */ 381 if (he >= hs + BLOCKSIZE) 382 break; 383 } 384 385 /* back down to a block boundary */ 386 he &= BLOCKMASK; 387 388 /* 389 * 1) Don't go beyond the end of the buffer. 390 * 2) If the end of the buffer is less than 391 * BLOCKSIZE bytes away, we're at the end 392 * of the file, so just grab what's left. 393 */ 394 if (hs + BLOCKSIZE > nr) 395 hs = he = nr; 396 397 /* 398 * At this point, we have a partial ordering: 399 * nw <= hs <= he <= nr 400 * If hs > nw, buf[nw..hs] contains non-zero data. 401 * If he > hs, buf[hs..he] is all zeroes. 402 */ 403 if (hs > nw) 404 if (fwrite(buf + nw, hs - nw, 1, fp) != 1) 405 break; 406 if (he > hs) 407 if (fseek(fp, he - hs, SEEK_CUR) == -1) 408 break; 409 } 410 } 411 if (nw != wl) { 412 syslog(LOG_ERR, 413 "write error on vmcore.%d file: %m", bounds); 414 syslog(LOG_WARNING, 415 "WARNING: vmcore may be incomplete"); 416 nerr++; 417 goto closeall; 418 } 419 if (verbose) { 420 dmpcnt += wl; 421 printf("%llu\r", (unsigned long long)dmpcnt); 422 fflush(stdout); 423 } 424 dumpsize -= wl; 425 } 426 if (verbose) 427 printf("\n"); 428 429 if (fclose(fp) < 0) { 430 syslog(LOG_ERR, "error on vmcore.%d: %m", bounds); 431 nerr++; 432 goto closeall; 433 } 434 nsaved++; 435 436 if (verbose) 437 printf("dump saved\n"); 438 439 nuke: 440 if (clear || !keep) { 441 if (verbose) 442 printf("clearing dump header\n"); 443 memcpy(kdhl.magic, KERNELDUMPMAGIC_CLEARED, sizeof kdhl.magic); 444 lseek(fd, lasthd, SEEK_SET); 445 error = write(fd, &kdhl, sizeof kdhl); 446 if (error != sizeof kdhl) 447 syslog(LOG_ERR, 448 "error while clearing the dump header: %m"); 449 } 450 close(fd); 451 return; 452 453 closeall: 454 fclose(fp); 455 456 closefd: 457 close(fd); 458 } 459 460 static void 461 usage(void) 462 { 463 fprintf(stderr, "usage: savecore [-cfkv] [directory [device...]]\n"); 464 exit (1); 465 } 466 467 int 468 main(int argc, char **argv) 469 { 470 int i, ch, error; 471 struct fstab *fsp; 472 char *savedir; 473 474 openlog("savecore", LOG_PERROR, LOG_DAEMON); 475 476 savedir = strdup("."); 477 if (savedir == NULL) { 478 syslog(LOG_ERR, "Cannot allocate memory"); 479 exit(1); 480 } 481 while ((ch = getopt(argc, argv, "cdfkN:vz")) != -1) 482 switch(ch) { 483 case 'c': 484 clear = 1; 485 break; 486 case 'k': 487 keep = 1; 488 break; 489 case 'v': 490 verbose = 1; 491 break; 492 case 'f': 493 force = 1; 494 break; 495 case 'z': 496 compress = 1; 497 break; 498 case 'd': /* Obsolete */ 499 case 'N': 500 case '?': 501 default: 502 usage(); 503 } 504 argc -= optind; 505 argv += optind; 506 if (argc >= 1) { 507 error = chdir(argv[0]); 508 if (error) { 509 syslog(LOG_ERR, "chdir(%s): %m", argv[0]); 510 exit(1); 511 } 512 savedir = argv[0]; 513 argc--; 514 argv++; 515 } 516 if (argc == 0) { 517 for (;;) { 518 fsp = getfsent(); 519 if (fsp == NULL) 520 break; 521 if (strcmp(fsp->fs_vfstype, "swap") && 522 strcmp(fsp->fs_vfstype, "dump")) 523 continue; 524 DoFile(savedir, fsp->fs_spec); 525 } 526 } else { 527 for (i = 0; i < argc; i++) 528 DoFile(savedir, argv[i]); 529 } 530 531 /* Emit minimal output. */ 532 if (nfound == 0) 533 syslog(LOG_WARNING, "no dumps found"); 534 else if (nsaved == 0) { 535 if (nerr != 0) 536 syslog(LOG_WARNING, "unsaved dumps found but not saved"); 537 else 538 syslog(LOG_WARNING, "no unsaved dumps found"); 539 } 540 541 return (0); 542 } 543