1 /*- 2 * Copyright (c) 1986, 1992, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * %sccs.include.redist.c% 6 */ 7 8 #ifndef lint 9 static char copyright[] = 10 "@(#) Copyright (c) 1986, 1992, 1993\n\ 11 The Regents of the University of California. All rights reserved.\n"; 12 #endif /* not lint */ 13 14 #ifndef lint 15 static char sccsid[] = "@(#)savecore.c 8.2 (Berkeley) 11/24/93"; 16 #endif /* not lint */ 17 18 #include <sys/param.h> 19 #include <sys/stat.h> 20 #include <sys/mount.h> 21 #include <sys/syslog.h> 22 #include <sys/time.h> 23 24 #include <dirent.h> 25 #include <errno.h> 26 #include <fcntl.h> 27 #include <nlist.h> 28 #include <paths.h> 29 #include <stdio.h> 30 #include <stdlib.h> 31 #include <string.h> 32 #include <tzfile.h> 33 #include <unistd.h> 34 35 #define ok(number) ((number) - KERNBASE) 36 37 struct nlist current_nl[] = { /* Namelist for currently running system. */ 38 #define X_DUMPDEV 0 39 { "_dumpdev" }, 40 #define X_DUMPLO 1 41 { "_dumplo" }, 42 #define X_TIME 2 43 { "_time" }, 44 #define X_DUMPSIZE 3 45 { "_dumpsize" }, 46 #define X_VERSION 4 47 { "_version" }, 48 #define X_PANICSTR 5 49 { "_panicstr" }, 50 #define X_DUMPMAG 6 51 { "_dumpmag" }, 52 { "" }, 53 }; 54 int cursyms[] = { X_DUMPDEV, X_DUMPLO, X_VERSION, X_DUMPMAG, -1 }; 55 int dumpsyms[] = { X_TIME, X_DUMPSIZE, X_VERSION, X_PANICSTR, X_DUMPMAG, -1 }; 56 57 struct nlist dump_nl[] = { /* Name list for dumped system. */ 58 { "_dumpdev" }, /* Entries MUST be the same as */ 59 { "_dumplo" }, /* those in current_nl[]. */ 60 { "_time" }, 61 { "_dumpsize" }, 62 { "_version" }, 63 { "_panicstr" }, 64 { "_dumpmag" }, 65 { "" }, 66 }; 67 68 /* Types match kernel declarations. */ 69 long dumplo; /* where dump starts on dumpdev */ 70 int dumpmag; /* magic number in dump */ 71 int dumpsize; /* amount of memory dumped */ 72 73 char *vmunix; 74 char *dirname; /* directory to save dumps in */ 75 char *ddname; /* name of dump device */ 76 dev_t dumpdev; /* dump device */ 77 int dumpfd; /* read/write descriptor on block dev */ 78 time_t now; /* current date */ 79 char panic_mesg[1024]; 80 int panicstr; 81 char vers[1024]; 82 83 int clear, compress, force, verbose; /* flags */ 84 85 void check_kmem __P((void)); 86 int check_space __P((void)); 87 void clear_dump __P((void)); 88 int Create __P((char *, int)); 89 int dump_exists __P((void)); 90 char *find_dev __P((dev_t, int)); 91 int get_crashtime __P((void)); 92 void kmem_setup __P((void)); 93 void log __P((int, char *, ...)); 94 void Lseek __P((int, off_t, int)); 95 int Open __P((char *, int rw)); 96 int Read __P((int, void *, int)); 97 char *rawname __P((char *s)); 98 void save_core __P((void)); 99 void usage __P((void)); 100 void Write __P((int, void *, int)); 101 102 int 103 main(argc, argv) 104 int argc; 105 char *argv[]; 106 { 107 int ch; 108 109 openlog("savecore", LOG_PERROR, LOG_DAEMON); 110 111 while ((ch = getopt(argc, argv, "cdfNvz")) != EOF) 112 switch(ch) { 113 case 'c': 114 clear = 1; 115 break; 116 case 'd': /* Not documented. */ 117 case 'v': 118 verbose = 1; 119 break; 120 case 'f': 121 force = 1; 122 break; 123 case 'N': 124 vmunix = optarg; 125 break; 126 case 'z': 127 compress = 1; 128 break; 129 case '?': 130 default: 131 usage(); 132 } 133 argc -= optind; 134 argv += optind; 135 136 if (!clear) { 137 if (argc != 1 && argc != 2) 138 usage(); 139 dirname = argv[0]; 140 } 141 if (argc == 2) 142 vmunix = argv[1]; 143 144 (void)time(&now); 145 kmem_setup(); 146 147 if (clear) { 148 clear_dump(); 149 exit(0); 150 } 151 152 if (!dump_exists() && !force) 153 exit(1); 154 155 check_kmem(); 156 157 if (panicstr) 158 syslog(LOG_ALERT, "reboot after panic: %s", panic_mesg); 159 else 160 syslog(LOG_ALERT, "reboot"); 161 162 if ((!get_crashtime() || !check_space()) && !force) 163 exit(1); 164 165 save_core(); 166 167 clear_dump(); 168 exit(0); 169 } 170 171 void 172 kmem_setup() 173 { 174 FILE *fp; 175 int kmem, i; 176 char *dump_sys; 177 178 /* 179 * Some names we need for the currently running system, others for 180 * the system that was running when the dump was made. The values 181 * obtained from the current system are used to look for things in 182 * /dev/kmem that cannot be found in the dump_sys namelist, but are 183 * presumed to be the same (since the disk partitions are probably 184 * the same!) 185 */ 186 if ((nlist(_PATH_UNIX, current_nl)) == -1) 187 syslog(LOG_ERR, "%s: nlist: %s", _PATH_UNIX, strerror(errno)); 188 for (i = 0; cursyms[i] != -1; i++) 189 if (current_nl[cursyms[i]].n_value == 0) { 190 syslog(LOG_ERR, "%s: %s not in namelist", 191 _PATH_UNIX, current_nl[cursyms[i]].n_name); 192 exit(1); 193 } 194 195 dump_sys = vmunix ? vmunix : _PATH_UNIX; 196 if ((nlist(dump_sys, dump_nl)) == -1) 197 syslog(LOG_ERR, "%s: nlist: %s", dump_sys, strerror(errno)); 198 for (i = 0; dumpsyms[i] != -1; i++) 199 if (dump_nl[dumpsyms[i]].n_value == 0) { 200 syslog(LOG_ERR, "%s: %s not in namelist", 201 dump_sys, dump_nl[dumpsyms[i]].n_name); 202 exit(1); 203 } 204 205 kmem = Open(_PATH_KMEM, O_RDONLY); 206 Lseek(kmem, (off_t)current_nl[X_DUMPDEV].n_value, L_SET); 207 (void)Read(kmem, &dumpdev, sizeof(dumpdev)); 208 Lseek(kmem, (off_t)current_nl[X_DUMPLO].n_value, L_SET); 209 (void)Read(kmem, &dumplo, sizeof(dumplo)); 210 if (verbose) 211 (void)printf("dumplo = %d (%d * %d)\n", 212 dumplo, dumplo/DEV_BSIZE, DEV_BSIZE); 213 Lseek(kmem, (off_t)current_nl[X_DUMPMAG].n_value, L_SET); 214 (void)Read(kmem, &dumpmag, sizeof(dumpmag)); 215 dumplo *= DEV_BSIZE; 216 ddname = find_dev(dumpdev, S_IFBLK); 217 dumpfd = Open(ddname, O_RDWR); 218 fp = fdopen(kmem, "r"); 219 if (fp == NULL) { 220 syslog(LOG_ERR, "%s: fdopen: %m", _PATH_KMEM); 221 exit(1); 222 } 223 if (vmunix) 224 return; 225 (void)fseek(fp, (off_t)current_nl[X_VERSION].n_value, L_SET); 226 (void)fgets(vers, sizeof(vers), fp); 227 228 /* Don't fclose(fp), we use dumpfd later. */ 229 } 230 231 void 232 check_kmem() 233 { 234 register char *cp; 235 FILE *fp; 236 char core_vers[1024]; 237 238 fp = fdopen(dumpfd, "r"); 239 if (fp == NULL) { 240 syslog(LOG_ERR, "%s: fdopen: %m", ddname); 241 exit(1); 242 } 243 fseek(fp, (off_t)(dumplo + ok(dump_nl[X_VERSION].n_value)), L_SET); 244 fgets(core_vers, sizeof(core_vers), fp); 245 if (strcmp(vers, core_vers) && vmunix == 0) 246 syslog(LOG_WARNING, 247 "warning: %s version mismatch:\n\t%s\nand\t%s\n", 248 _PATH_UNIX, vers, core_vers); 249 (void)fseek(fp, 250 (off_t)(dumplo + ok(dump_nl[X_PANICSTR].n_value)), L_SET); 251 (void)fread(&panicstr, sizeof(panicstr), 1, fp); 252 if (panicstr) { 253 (void)fseek(fp, dumplo + ok(panicstr), L_SET); 254 cp = panic_mesg; 255 do 256 *cp = getc(fp); 257 while (*cp++ && cp < &panic_mesg[sizeof(panic_mesg)]); 258 } 259 /* Don't fclose(fp), we use dumpfd later. */ 260 } 261 262 void 263 clear_dump() 264 { 265 long newdumplo; 266 267 newdumplo = 0; 268 Lseek(dumpfd, (off_t)(dumplo + ok(dump_nl[X_DUMPMAG].n_value)), L_SET); 269 Write(dumpfd, &newdumplo, sizeof(newdumplo)); 270 } 271 272 int 273 dump_exists() 274 { 275 int newdumpmag; 276 277 Lseek(dumpfd, (off_t)(dumplo + ok(dump_nl[X_DUMPMAG].n_value)), L_SET); 278 (void)Read(dumpfd, &newdumpmag, sizeof(newdumpmag)); 279 if (newdumpmag != dumpmag) { 280 if (verbose) 281 syslog(LOG_WARNING, "magic number mismatch (%x != %x)", 282 newdumpmag, dumpmag); 283 syslog(LOG_WARNING, "no core dump"); 284 return (0); 285 } 286 return (1); 287 } 288 289 char buf[1024 * 1024]; 290 291 void 292 save_core() 293 { 294 register FILE *fp; 295 register int bounds, ifd, nr, nw, ofd; 296 char *rawp, path[MAXPATHLEN]; 297 298 /* 299 * Get the current number and update the bounds file. Do the update 300 * now, because may fail later and don't want to overwrite anything. 301 */ 302 (void)snprintf(path, sizeof(path), "%s/bounds", dirname); 303 if ((fp = fopen(path, "r")) == NULL) 304 goto err1; 305 if (fgets(buf, sizeof(buf), fp) == NULL) { 306 if (ferror(fp)) 307 err1: syslog(LOG_WARNING, "%s: %s", path, strerror(errno)); 308 bounds = 0; 309 } else 310 bounds = atoi(buf); 311 if (fp != NULL) 312 (void)fclose(fp); 313 if ((fp = fopen(path, "w")) == NULL) 314 syslog(LOG_ERR, "%s: %m", path); 315 else { 316 (void)fprintf(fp, "%d\n", bounds + 1); 317 (void)fclose(fp); 318 } 319 (void)fclose(fp); 320 321 /* Create the core file. */ 322 (void)snprintf(path, sizeof(path), "%s/vmcore.%d%s", 323 dirname, bounds, compress ? ".Z" : ""); 324 if (compress) { 325 if ((fp = zopen(path, "w", 0)) == NULL) { 326 syslog(LOG_ERR, "%s: %s", path, strerror(errno)); 327 exit(1); 328 } 329 } else 330 ofd = Create(path, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH); 331 332 /* Open the raw device. */ 333 rawp = rawname(ddname); 334 if ((ifd = open(rawp, O_RDONLY)) == -1) { 335 syslog(LOG_WARNING, "%s: %m; using block device", rawp); 336 ifd = dumpfd; 337 } 338 339 /* Read the dump size. */ 340 Lseek(dumpfd, (off_t)(dumplo + ok(dump_nl[X_DUMPSIZE].n_value)), L_SET); 341 (void)Read(dumpfd, &dumpsize, sizeof(dumpsize)); 342 343 /* Seek to the start of the core. */ 344 Lseek(ifd, (off_t)dumplo, L_SET); 345 346 /* Copy the core file. */ 347 dumpsize *= NBPG; 348 syslog(LOG_NOTICE, "writing %score to %s", 349 compress ? "compressed " : "", path); 350 for (; dumpsize > 0; dumpsize -= nr) { 351 (void)printf("%6dK\r", dumpsize / 1024); 352 (void)fflush(stdout); 353 nr = read(ifd, buf, MIN(dumpsize, sizeof(buf))); 354 if (nr <= 0) { 355 if (nr == 0) 356 syslog(LOG_WARNING, 357 "WARNING: EOF on dump device"); 358 else 359 syslog(LOG_ERR, "%s: %m", rawp); 360 goto err2; 361 } 362 if (compress) 363 nw = fwrite(buf, 1, nr, fp); 364 else 365 nw = write(ofd, buf, nr); 366 if (nw != nr) { 367 syslog(LOG_ERR, "%s: %s", 368 path, strerror(nw == 0 ? EIO : errno)); 369 err2: syslog(LOG_WARNING, 370 "WARNING: vmcore may be incomplete"); 371 (void)printf("\n"); 372 exit(1); 373 } 374 } 375 (void)printf("\n"); 376 (void)close(ifd); 377 if (compress) 378 (void)fclose(fp); 379 else 380 (void)close(ofd); 381 382 /* Copy the kernel. */ 383 ifd = Open(vmunix ? vmunix : _PATH_UNIX, O_RDONLY); 384 (void)snprintf(path, sizeof(path), "%s/vmunix.%d%s", 385 dirname, bounds, compress ? ".Z" : ""); 386 if (compress) { 387 if ((fp = zopen(path, "w", 0)) == NULL) { 388 syslog(LOG_ERR, "%s: %s", path, strerror(errno)); 389 exit(1); 390 } 391 } else 392 ofd = Create(path, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH); 393 syslog(LOG_NOTICE, "writing %skernel to %s", 394 compress ? "compressed " : "", path); 395 while ((nr = read(ifd, buf, sizeof(buf))) > 0) { 396 if (compress) 397 nw = fwrite(buf, 1, nr, fp); 398 else 399 nw = write(ofd, buf, nr); 400 if (nw != nr) { 401 syslog(LOG_ERR, "%s: %s", 402 path, strerror(nw == 0 ? EIO : errno)); 403 syslog(LOG_WARNING, 404 "WARNING: vmunix may be incomplete"); 405 exit(1); 406 } 407 } 408 if (nr < 0) { 409 syslog(LOG_ERR, "%s: %s", 410 vmunix ? vmunix : _PATH_UNIX, strerror(errno)); 411 syslog(LOG_WARNING, 412 "WARNING: vmunix may be incomplete"); 413 exit(1); 414 } 415 if (compress) 416 (void)fclose(fp); 417 else 418 (void)close(ofd); 419 } 420 421 char * 422 find_dev(dev, type) 423 register dev_t dev; 424 register int type; 425 { 426 register DIR *dfd; 427 struct dirent *dir; 428 struct stat sb; 429 char *dp, devname[MAXPATHLEN + 1]; 430 431 if ((dfd = opendir(_PATH_DEV)) == NULL) { 432 syslog(LOG_ERR, "%s: %s", _PATH_DEV, strerror(errno)); 433 exit(1); 434 } 435 (void)strcpy(devname, _PATH_DEV); 436 while ((dir = readdir(dfd))) { 437 (void)strcpy(devname + sizeof(_PATH_DEV) - 1, dir->d_name); 438 if (stat(devname, &sb)) { 439 syslog(LOG_ERR, "%s: %s", devname, strerror(errno)); 440 continue; 441 } 442 if ((sb.st_mode & S_IFMT) != type) 443 continue; 444 if (dev == sb.st_rdev) { 445 closedir(dfd); 446 if ((dp = strdup(devname)) == NULL) { 447 syslog(LOG_ERR, "%s", strerror(errno)); 448 exit(1); 449 } 450 return (dp); 451 } 452 } 453 closedir(dfd); 454 syslog(LOG_ERR, "can't find device %d/%d", major(dev), minor(dev)); 455 exit(1); 456 } 457 458 char * 459 rawname(s) 460 char *s; 461 { 462 char *sl, name[MAXPATHLEN]; 463 464 if ((sl = rindex(s, '/')) == NULL || sl[1] == '0') { 465 syslog(LOG_ERR, 466 "can't make raw dump device name from %s", s); 467 return (s); 468 } 469 (void)snprintf(name, sizeof(name), "%.*s/r%s", sl - s, s, sl + 1); 470 if ((sl = strdup(name)) == NULL) { 471 syslog(LOG_ERR, "%s", strerror(errno)); 472 exit(1); 473 } 474 return (sl); 475 } 476 477 int 478 get_crashtime() 479 { 480 time_t dumptime; /* Time the dump was taken. */ 481 482 Lseek(dumpfd, (off_t)(dumplo + ok(dump_nl[X_TIME].n_value)), L_SET); 483 (void)Read(dumpfd, &dumptime, sizeof(dumptime)); 484 if (dumptime == 0) { 485 if (verbose) 486 syslog(LOG_ERR, "dump time is zero"); 487 return (0); 488 } 489 (void)printf("savecore: system went down at %s", ctime(&dumptime)); 490 #define LEEWAY (7 * SECSPERDAY) 491 if (dumptime < now - LEEWAY || dumptime > now + LEEWAY) { 492 (void)printf("dump time is unreasonable\n"); 493 return (0); 494 } 495 return (1); 496 } 497 498 int 499 check_space() 500 { 501 register FILE *fp; 502 char *tvmunix; 503 off_t minfree, spacefree, vmunixsize, needed; 504 struct stat st; 505 struct statfs fsbuf; 506 char buf[100], path[MAXPATHLEN]; 507 508 tvmunix = vmunix ? vmunix : _PATH_UNIX; 509 if (stat(tvmunix, &st) < 0) { 510 syslog(LOG_ERR, "%s: %m", tvmunix); 511 exit(1); 512 } 513 vmunixsize = st.st_blocks * S_BLKSIZE; 514 if (statfs(dirname, &fsbuf) < 0) { 515 syslog(LOG_ERR, "%s: %m", dirname); 516 exit(1); 517 } 518 spacefree = (fsbuf.f_bavail * fsbuf.f_bsize) / 1024; 519 520 (void)snprintf(path, sizeof(path), "%s/minfree", dirname); 521 if ((fp = fopen(path, "r")) == NULL) 522 minfree = 0; 523 else { 524 if (fgets(buf, sizeof(buf), fp) == NULL) 525 minfree = 0; 526 else 527 minfree = atoi(buf); 528 (void)fclose(fp); 529 } 530 531 needed = (dumpsize + vmunixsize) / 1024; 532 if (minfree > 0 && spacefree - needed < minfree) { 533 syslog(LOG_WARNING, 534 "no dump, not enough free space on device"); 535 return (0); 536 } 537 if (spacefree - needed < minfree) 538 syslog(LOG_WARNING, 539 "dump performed, but free space threshold crossed"); 540 return (1); 541 } 542 543 int 544 Open(name, rw) 545 char *name; 546 int rw; 547 { 548 int fd; 549 550 if ((fd = open(name, rw, 0)) < 0) { 551 syslog(LOG_ERR, "%s: %m", name); 552 exit(1); 553 } 554 return (fd); 555 } 556 557 int 558 Read(fd, bp, size) 559 int fd, size; 560 void *bp; 561 { 562 int nr; 563 564 nr = read(fd, bp, size); 565 if (nr != size) { 566 syslog(LOG_ERR, "read: %m"); 567 exit(1); 568 } 569 return (nr); 570 } 571 572 void 573 Lseek(fd, off, flag) 574 int fd, flag; 575 off_t off; 576 { 577 off_t ret; 578 579 ret = lseek(fd, off, flag); 580 if (ret == -1) { 581 syslog(LOG_ERR, "lseek: %m"); 582 exit(1); 583 } 584 } 585 586 int 587 Create(file, mode) 588 char *file; 589 int mode; 590 { 591 register int fd; 592 593 fd = creat(file, mode); 594 if (fd < 0) { 595 syslog(LOG_ERR, "%s: %m", file); 596 exit(1); 597 } 598 return (fd); 599 } 600 601 void 602 Write(fd, bp, size) 603 int fd, size; 604 void *bp; 605 { 606 int n; 607 608 if ((n = write(fd, bp, size)) < size) { 609 syslog(LOG_ERR, "write: %s", strerror(n == -1 ? errno : EIO)); 610 exit(1); 611 } 612 } 613 614 void 615 usage() 616 { 617 (void)syslog(LOG_ERR, "usage: savecore [-cfvz] [-N system] directory"); 618 exit(1); 619 } 620