1 /* $OpenBSD: syslogd.c,v 1.58 2002/11/21 07:46:48 cloder Exp $ */ 2 3 /* 4 * Copyright (c) 1983, 1988, 1993, 1994 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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 36 #ifndef lint 37 static char copyright[] = 38 "@(#) Copyright (c) 1983, 1988, 1993, 1994\n\ 39 The Regents of the University of California. All rights reserved.\n"; 40 #endif /* not lint */ 41 42 #ifndef lint 43 #if 0 44 static char sccsid[] = "@(#)syslogd.c 8.3 (Berkeley) 4/4/94"; 45 #else 46 static char rcsid[] = "$OpenBSD: syslogd.c,v 1.58 2002/11/21 07:46:48 cloder Exp $"; 47 #endif 48 #endif /* not lint */ 49 50 /* 51 * syslogd -- log system messages 52 * 53 * This program implements a system log. It takes a series of lines. 54 * Each line may have a priority, signified as "<n>" as 55 * the first characters of the line. If this is 56 * not present, a default priority is used. 57 * 58 * To kill syslogd, send a signal 15 (terminate). A signal 1 (hup) will 59 * cause it to reread its configuration file. 60 * 61 * Defined Constants: 62 * 63 * MAXLINE -- the maximum line length that can be handled. 64 * DEFUPRI -- the default priority for user messages 65 * DEFSPRI -- the default priority for kernel messages 66 * 67 * Author: Eric Allman 68 * extensive changes by Ralph Campbell 69 * more extensive changes by Eric Allman (again) 70 */ 71 72 #define MAXLINE 1024 /* maximum line length */ 73 #define MAXSVLINE 120 /* maximum saved line length */ 74 #define DEFUPRI (LOG_USER|LOG_NOTICE) 75 #define DEFSPRI (LOG_KERN|LOG_CRIT) 76 #define TIMERINTVL 30 /* interval for checking flush, mark */ 77 #define TTYMSGTIME 1 /* timeout passed to ttymsg */ 78 79 #include <sys/param.h> 80 #include <sys/ioctl.h> 81 #include <sys/stat.h> 82 #include <sys/wait.h> 83 #include <sys/socket.h> 84 #include <sys/msgbuf.h> 85 #include <sys/uio.h> 86 #include <sys/sysctl.h> 87 #include <sys/un.h> 88 #include <sys/time.h> 89 #include <sys/resource.h> 90 91 #include <netinet/in.h> 92 #include <netdb.h> 93 #include <arpa/inet.h> 94 95 #include <ctype.h> 96 #include <errno.h> 97 #include <err.h> 98 #include <fcntl.h> 99 #include <paths.h> 100 #include <signal.h> 101 #include <stdio.h> 102 #include <stdlib.h> 103 #include <string.h> 104 #include <unistd.h> 105 #include <utmp.h> 106 #include <vis.h> 107 108 #define SYSLOG_NAMES 109 #include <sys/syslog.h> 110 111 char *ConfFile = _PATH_LOGCONF; 112 char *PidFile = _PATH_LOGPID; 113 char ctty[] = _PATH_CONSOLE; 114 115 #define dprintf if (Debug) printf 116 117 #define MAXUNAMES 20 /* maximum number of user names */ 118 119 /* 120 * Flags to logmsg(). 121 */ 122 123 #define IGN_CONS 0x001 /* don't print on console */ 124 #define SYNC_FILE 0x002 /* do fsync on file after printing */ 125 #define ADDDATE 0x004 /* add a date to the message */ 126 #define MARK 0x008 /* this message is a mark */ 127 128 /* 129 * This structure represents the files that will have log 130 * copies printed. 131 */ 132 133 struct filed { 134 struct filed *f_next; /* next in linked list */ 135 short f_type; /* entry type, see below */ 136 short f_file; /* file descriptor */ 137 time_t f_time; /* time this was last written */ 138 u_char f_pmask[LOG_NFACILITIES+1]; /* priority mask */ 139 char *f_program; /* program this applies to */ 140 union { 141 char f_uname[MAXUNAMES][UT_NAMESIZE+1]; 142 struct { 143 char f_hname[MAXHOSTNAMELEN]; 144 struct sockaddr_in f_addr; 145 } f_forw; /* forwarding address */ 146 char f_fname[MAXPATHLEN]; 147 } f_un; 148 char f_prevline[MAXSVLINE]; /* last message logged */ 149 char f_lasttime[16]; /* time of last occurrence */ 150 char f_prevhost[MAXHOSTNAMELEN]; /* host from which recd. */ 151 int f_prevpri; /* pri of f_prevline */ 152 int f_prevlen; /* length of f_prevline */ 153 int f_prevcount; /* repetition cnt of prevline */ 154 int f_repeatcount; /* number of "repeated" msgs */ 155 }; 156 157 /* 158 * Intervals at which we flush out "message repeated" messages, 159 * in seconds after previous message is logged. After each flush, 160 * we move to the next interval until we reach the largest. 161 */ 162 int repeatinterval[] = { 30, 120, 600 }; /* # of secs before flush */ 163 #define MAXREPEAT ((sizeof(repeatinterval) / sizeof(repeatinterval[0])) - 1) 164 #define REPEATTIME(f) ((f)->f_time + repeatinterval[(f)->f_repeatcount]) 165 #define BACKOFF(f) { if (++(f)->f_repeatcount > MAXREPEAT) \ 166 (f)->f_repeatcount = MAXREPEAT; \ 167 } 168 169 /* values for f_type */ 170 #define F_UNUSED 0 /* unused entry */ 171 #define F_FILE 1 /* regular file */ 172 #define F_TTY 2 /* terminal */ 173 #define F_CONSOLE 3 /* console terminal */ 174 #define F_FORW 4 /* remote machine */ 175 #define F_USERS 5 /* list of users */ 176 #define F_WALL 6 /* everyone logged on */ 177 178 char *TypeNames[7] = { 179 "UNUSED", "FILE", "TTY", "CONSOLE", 180 "FORW", "USERS", "WALL" 181 }; 182 183 struct filed *Files; 184 struct filed consfile; 185 186 int Debug; /* debug flag */ 187 char LocalHostName[MAXHOSTNAMELEN]; /* our hostname */ 188 char *LocalDomain; /* our local domain name */ 189 int InetInuse = 0; /* non-zero if INET sockets are being used */ 190 int finet; /* Internet datagram socket */ 191 int LogPort; /* port number for INET connections */ 192 int Initialized = 0; /* set when we have initialized ourselves */ 193 194 int MarkInterval = 20 * 60; /* interval between marks in seconds */ 195 int MarkSeq = 0; /* mark sequence number */ 196 int SecureMode = 1; /* when true, speak only unix domain socks */ 197 int NoDNS = 0; /* when true, will refrain from doing DNS lookups */ 198 199 volatile sig_atomic_t MarkSet; 200 volatile sig_atomic_t WantDie; 201 volatile sig_atomic_t DoInit; 202 203 void cfline(char *, struct filed *, char *); 204 char *cvthname(struct sockaddr_in *); 205 int decode(const char *, CODE *); 206 void dodie(int); 207 void doinit(int); 208 void die(int); 209 void domark(int); 210 void markit(void); 211 void fprintlog(struct filed *, int, char *); 212 void init(void); 213 void logerror(char *); 214 void logmsg(int, char *, char *, int); 215 void printline(char *, char *); 216 void printsys(char *); 217 void reapchild(int); 218 char *ttymsg(struct iovec *, int, char *, int); 219 void usage(void); 220 void wallmsg(struct filed *, struct iovec *); 221 int getmsgbufsize(void); 222 223 #define MAXFUNIX 21 224 225 int nfunix = 1; 226 char *funixn[MAXFUNIX] = { _PATH_LOG }; 227 int funix[MAXFUNIX]; 228 229 int 230 main(int argc, char *argv[]) 231 { 232 int ch, i, fklog, linesize, fdsrmax = 0; 233 struct sockaddr_un sunx, fromunix; 234 struct sockaddr_in sin, frominet; 235 socklen_t slen, len; 236 fd_set *fdsr = NULL; 237 char *p, *line; 238 FILE *fp; 239 240 while ((ch = getopt(argc, argv, "dnuf:m:p:a:")) != -1) 241 switch (ch) { 242 case 'd': /* debug */ 243 Debug++; 244 break; 245 case 'f': /* configuration file */ 246 ConfFile = optarg; 247 break; 248 case 'm': /* mark interval */ 249 MarkInterval = atoi(optarg) * 60; 250 break; 251 case 'n': /* don't do DNS lookups */ 252 NoDNS = 1; 253 break; 254 case 'p': /* path */ 255 funixn[0] = optarg; 256 break; 257 case 'u': /* allow udp input port */ 258 SecureMode = 0; 259 break; 260 case 'a': 261 if (nfunix >= MAXFUNIX) 262 fprintf(stderr, 263 "syslogd: out of descriptors, ignoring %s\n", 264 optarg); 265 else if (strlen(optarg) >= sizeof(sunx.sun_path)) 266 fprintf(stderr, 267 "syslogd: path too long, ignoring %s\n", 268 optarg); 269 else 270 funixn[nfunix++] = optarg; 271 break; 272 case '?': 273 default: 274 usage(); 275 } 276 if ((argc -= optind) != 0) 277 usage(); 278 279 if (!Debug) 280 (void)daemon(0, 0); 281 else 282 setlinebuf(stdout); 283 284 consfile.f_type = F_CONSOLE; 285 (void)strlcpy(consfile.f_un.f_fname, ctty, 286 sizeof(consfile.f_un.f_fname)); 287 (void)gethostname(LocalHostName, sizeof(LocalHostName)); 288 if ((p = strchr(LocalHostName, '.')) != NULL) { 289 *p++ = '\0'; 290 LocalDomain = p; 291 } else 292 LocalDomain = ""; 293 294 linesize = getmsgbufsize(); 295 if (linesize < MAXLINE) 296 linesize = MAXLINE; 297 linesize++; 298 line = malloc(linesize); 299 300 (void)signal(SIGHUP, doinit); 301 (void)signal(SIGTERM, dodie); 302 (void)signal(SIGINT, Debug ? dodie : SIG_IGN); 303 (void)signal(SIGQUIT, Debug ? dodie : SIG_IGN); 304 (void)signal(SIGCHLD, reapchild); 305 (void)signal(SIGALRM, domark); 306 (void)alarm(TIMERINTVL); 307 308 #ifndef SUN_LEN 309 #define SUN_LEN(unp) (strlen((unp)->sun_path) + 2) 310 #endif 311 for (i = 0; i < nfunix; i++) { 312 (void)unlink(funixn[i]); 313 314 memset(&sunx, 0, sizeof(sunx)); 315 sunx.sun_family = AF_UNIX; 316 (void)strlcpy(sunx.sun_path, funixn[i], sizeof(sunx.sun_path)); 317 funix[i] = socket(AF_UNIX, SOCK_DGRAM, 0); 318 if (funix[i] < 0 || 319 bind(funix[i], (struct sockaddr *)&sunx, 320 SUN_LEN(&sunx)) < 0 || 321 chmod(funixn[i], 0666) < 0) { 322 (void)snprintf(line, linesize, "cannot create %s", 323 funixn[i]); 324 logerror(line); 325 dprintf("cannot create %s (%d)\n", funixn[i], errno); 326 if (i == 0) 327 die(0); 328 } 329 /* double socket receive buffer size */ 330 if (getsockopt(funix[i], SOL_SOCKET, SO_RCVBUF, &len, 331 &slen) == 0) { 332 len *= 2; 333 (void)setsockopt(funix[i], SOL_SOCKET, SO_RCVBUF, &len, 334 slen); 335 } 336 } 337 finet = socket(AF_INET, SOCK_DGRAM, 0); 338 if (finet >= 0) { 339 struct servent *sp; 340 341 sp = getservbyname("syslog", "udp"); 342 if (sp == NULL) { 343 errno = 0; 344 logerror("syslog/udp: unknown service"); 345 die(0); 346 } 347 memset(&sin, 0, sizeof(sin)); 348 sin.sin_len = sizeof(sin); 349 sin.sin_family = AF_INET; 350 sin.sin_port = LogPort = sp->s_port; 351 if (bind(finet, (struct sockaddr *)&sin, sizeof(sin)) < 0) { 352 logerror("bind"); 353 if (!Debug) 354 die(0); 355 } else { 356 InetInuse = 1; 357 /* double socket receive buffer size */ 358 if (getsockopt(finet, SOL_SOCKET, SO_RCVBUF, &len, 359 &slen) == 0) { 360 len *= 2; 361 (void)setsockopt(funix[i], SOL_SOCKET, 362 SO_RCVBUF, &len, slen); 363 } 364 } 365 } 366 if ((fklog = open(_PATH_KLOG, O_RDONLY, 0)) < 0) 367 dprintf("can't open %s (%d)\n", _PATH_KLOG, errno); 368 369 /* tuck my process id away */ 370 if (!Debug) { 371 fp = fopen(PidFile, "w"); 372 if (fp != NULL) { 373 fprintf(fp, "%ld\n", (long)getpid()); 374 (void) fclose(fp); 375 } 376 } 377 378 dprintf("off & running....\n"); 379 380 init(); 381 382 if (fklog != -1 && fklog > fdsrmax) 383 fdsrmax = fklog; 384 if (finet != -1 && finet > fdsrmax) 385 fdsrmax = finet; 386 for (i = 0; i < nfunix; i++) { 387 if (funix[i] != -1 && funix[i] > fdsrmax) 388 fdsrmax = funix[i]; 389 } 390 391 fdsr = (fd_set *)calloc(howmany(fdsrmax+1, NFDBITS), 392 sizeof(fd_mask)); 393 if (fdsr == NULL) 394 errx(1, "calloc fd_set"); 395 396 for (;;) { 397 if (MarkSet) 398 markit(); 399 if (WantDie) 400 die(WantDie); 401 402 if (DoInit) { 403 init(); 404 DoInit = 0; 405 } 406 407 bzero(fdsr, howmany(fdsrmax+1, NFDBITS) * 408 sizeof(fd_mask)); 409 410 if (fklog != -1) 411 FD_SET(fklog, fdsr); 412 if (finet != -1) 413 FD_SET(finet, fdsr); 414 for (i = 0; i < nfunix; i++) { 415 if (funix[i] != -1) 416 FD_SET(funix[i], fdsr); 417 } 418 419 switch (select(fdsrmax+1, fdsr, NULL, NULL, NULL)) { 420 case 0: 421 continue; 422 case -1: 423 if (errno != EINTR) 424 logerror("select"); 425 continue; 426 } 427 428 if (fklog != -1 && FD_ISSET(fklog, fdsr)) { 429 i = read(fklog, line, linesize - 1); 430 if (i > 0) { 431 line[i] = '\0'; 432 printsys(line); 433 } else if (i < 0 && errno != EINTR) { 434 logerror("klog"); 435 fklog = -1; 436 } 437 } 438 if (finet != -1 && FD_ISSET(finet, fdsr)) { 439 len = sizeof(frominet); 440 i = recvfrom(finet, line, MAXLINE, 0, 441 (struct sockaddr *)&frominet, &len); 442 if (SecureMode) { 443 /* silently drop it */ 444 } else { 445 if (i > 0) { 446 line[i] = '\0'; 447 printline(cvthname(&frominet), line); 448 } else if (i < 0 && errno != EINTR) 449 logerror("recvfrom inet"); 450 } 451 } 452 453 for (i = 0; i < nfunix; i++) { 454 if (funix[i] != -1 && FD_ISSET(funix[i], fdsr)) { 455 len = sizeof(fromunix); 456 len = recvfrom(funix[i], line, MAXLINE, 0, 457 (struct sockaddr *)&fromunix, &len); 458 if (len > 0) { 459 line[len] = '\0'; 460 printline(LocalHostName, line); 461 } else if (len < 0 && errno != EINTR) 462 logerror("recvfrom unix"); 463 } 464 } 465 } 466 if (fdsr) 467 free(fdsr); 468 } 469 470 void 471 usage(void) 472 { 473 474 (void)fprintf(stderr, 475 "usage: syslogd [-dnu] [-f config_file] [-m mark_interval] " 476 "[-a path] [-p log_socket]\n"); 477 exit(1); 478 } 479 480 /* 481 * Take a raw input line, decode the message, and print the message 482 * on the appropriate log files. 483 */ 484 void 485 printline(char *hname, char *msg) 486 { 487 int pri; 488 char *p, *q, line[MAXLINE + 1]; 489 490 /* test for special codes */ 491 pri = DEFUPRI; 492 p = msg; 493 if (*p == '<') { 494 pri = 0; 495 while (isdigit(*++p)) 496 pri = 10 * pri + (*p - '0'); 497 if (*p == '>') 498 ++p; 499 } 500 if (pri &~ (LOG_FACMASK|LOG_PRIMASK)) 501 pri = DEFUPRI; 502 503 /* don't allow users to log kernel messages */ 504 if (LOG_FAC(pri) == LOG_KERN) 505 pri = LOG_MAKEPRI(LOG_USER, LOG_PRI(pri)); 506 507 for (q = line; *p && q < &line[sizeof(line) - 4]; p++) { 508 if (*p == '\n') 509 *q++ = ' '; 510 else 511 q = vis(q, *p, 0, 0); 512 } 513 *q = '\0'; 514 515 logmsg(pri, line, hname, 0); 516 } 517 518 /* 519 * Take a raw input line from /dev/klog, split and format similar to syslog(). 520 */ 521 void 522 printsys(char *msg) 523 { 524 int c, pri, flags; 525 char *lp, *p, *q, line[MAXLINE + 1]; 526 527 (void)snprintf(line, sizeof line, "%s: ", _PATH_UNIX); 528 lp = line + strlen(line); 529 for (p = msg; *p != '\0'; ) { 530 flags = SYNC_FILE | ADDDATE; /* fsync file after write */ 531 pri = DEFSPRI; 532 if (*p == '<') { 533 pri = 0; 534 while (isdigit(*++p)) 535 pri = 10 * pri + (*p - '0'); 536 if (*p == '>') 537 ++p; 538 } else { 539 /* kernel printf's come out on console */ 540 flags |= IGN_CONS; 541 } 542 if (pri &~ (LOG_FACMASK|LOG_PRIMASK)) 543 pri = DEFSPRI; 544 545 q = lp; 546 while (*p && (c = *p++) != '\n' && q < &line[sizeof(line) - 4]) 547 q = vis(q, c, 0, 0); 548 549 logmsg(pri, line, LocalHostName, flags); 550 } 551 } 552 553 time_t now; 554 555 /* 556 * Log a message to the appropriate log files, users, etc. based on 557 * the priority. 558 */ 559 void 560 logmsg(int pri, char *msg, char *from, int flags) 561 { 562 struct filed *f; 563 int fac, msglen, prilev, i; 564 sigset_t mask, omask; 565 char *timestamp; 566 char prog[NAME_MAX+1]; 567 568 dprintf("logmsg: pri 0%o, flags 0x%x, from %s, msg %s\n", 569 pri, flags, from, msg); 570 571 sigemptyset(&mask); 572 sigaddset(&mask, SIGALRM); 573 sigaddset(&mask, SIGHUP); 574 sigprocmask(SIG_BLOCK, &mask, &omask); 575 576 /* 577 * Check to see if msg looks non-standard. 578 */ 579 msglen = strlen(msg); 580 if (msglen < 16 || msg[3] != ' ' || msg[6] != ' ' || 581 msg[9] != ':' || msg[12] != ':' || msg[15] != ' ') 582 flags |= ADDDATE; 583 584 (void)time(&now); 585 if (flags & ADDDATE) 586 timestamp = ctime(&now) + 4; 587 else { 588 timestamp = msg; 589 msg += 16; 590 msglen -= 16; 591 } 592 593 /* extract facility and priority level */ 594 if (flags & MARK) 595 fac = LOG_NFACILITIES; 596 else 597 fac = LOG_FAC(pri); 598 prilev = LOG_PRI(pri); 599 600 /* extract program name */ 601 for(i = 0; i < NAME_MAX; i++) { 602 if (!isalnum(msg[i])) 603 break; 604 prog[i] = msg[i]; 605 } 606 prog[i] = 0; 607 608 /* log the message to the particular outputs */ 609 if (!Initialized) { 610 f = &consfile; 611 f->f_file = open(ctty, O_WRONLY|O_NONBLOCK, 0); 612 613 if (f->f_file >= 0) { 614 fprintlog(f, flags, msg); 615 (void)close(f->f_file); 616 f->f_file = -1; 617 } 618 (void)sigprocmask(SIG_SETMASK, &omask, NULL); 619 return; 620 } 621 for (f = Files; f; f = f->f_next) { 622 /* skip messages that are incorrect priority */ 623 if (f->f_pmask[fac] < prilev || 624 f->f_pmask[fac] == INTERNAL_NOPRI) 625 continue; 626 627 /* skip messages with the incorrect program name */ 628 if (f->f_program) 629 if (strcmp(prog, f->f_program) != 0) 630 continue; 631 632 if (f->f_type == F_CONSOLE && (flags & IGN_CONS)) 633 continue; 634 635 /* don't output marks to recently written files */ 636 if ((flags & MARK) && (now - f->f_time) < MarkInterval / 2) 637 continue; 638 639 /* 640 * suppress duplicate lines to this file 641 */ 642 if ((flags & MARK) == 0 && msglen == f->f_prevlen && 643 !strcmp(msg, f->f_prevline) && 644 !strcmp(from, f->f_prevhost)) { 645 strlcpy(f->f_lasttime, timestamp, 16); 646 f->f_prevcount++; 647 dprintf("msg repeated %d times, %ld sec of %d\n", 648 f->f_prevcount, (long)(now - f->f_time), 649 repeatinterval[f->f_repeatcount]); 650 /* 651 * If domark would have logged this by now, 652 * flush it now (so we don't hold isolated messages), 653 * but back off so we'll flush less often 654 * in the future. 655 */ 656 if (now > REPEATTIME(f)) { 657 fprintlog(f, flags, (char *)NULL); 658 BACKOFF(f); 659 } 660 } else { 661 /* new line, save it */ 662 if (f->f_prevcount) 663 fprintlog(f, 0, (char *)NULL); 664 f->f_repeatcount = 0; 665 f->f_prevpri = pri; 666 strlcpy(f->f_lasttime, timestamp, 16); 667 strlcpy(f->f_prevhost, from, 668 sizeof(f->f_prevhost)); 669 if (msglen < MAXSVLINE) { 670 f->f_prevlen = msglen; 671 strlcpy(f->f_prevline, msg, sizeof(f->f_prevline)); 672 fprintlog(f, flags, (char *)NULL); 673 } else { 674 f->f_prevline[0] = 0; 675 f->f_prevlen = 0; 676 fprintlog(f, flags, msg); 677 } 678 } 679 } 680 (void)sigprocmask(SIG_SETMASK, &omask, NULL); 681 } 682 683 void 684 fprintlog(struct filed *f, int flags, char *msg) 685 { 686 struct iovec iov[6]; 687 struct iovec *v; 688 int l; 689 char line[MAXLINE + 1], repbuf[80], greetings[500]; 690 691 v = iov; 692 if (f->f_type == F_WALL) { 693 if ((l = snprintf(greetings, sizeof(greetings), 694 "\r\n\7Message from syslogd@%s at %.24s ...\r\n", 695 f->f_prevhost, ctime(&now))) >= sizeof(greetings) || 696 l == -1) 697 l = strlen(greetings); 698 v->iov_base = greetings; 699 v->iov_len = l; 700 v++; 701 v->iov_base = ""; 702 v->iov_len = 0; 703 v++; 704 } else { 705 v->iov_base = f->f_lasttime; 706 v->iov_len = 15; 707 v++; 708 v->iov_base = " "; 709 v->iov_len = 1; 710 v++; 711 } 712 v->iov_base = f->f_prevhost; 713 v->iov_len = strlen(v->iov_base); 714 v++; 715 v->iov_base = " "; 716 v->iov_len = 1; 717 v++; 718 719 if (msg) { 720 v->iov_base = msg; 721 v->iov_len = strlen(msg); 722 } else if (f->f_prevcount > 1) { 723 if ((l = snprintf(repbuf, sizeof(repbuf), 724 "last message repeated %d times", f->f_prevcount)) >= 725 sizeof(repbuf) || l == -1) 726 l = strlen(repbuf); 727 v->iov_base = repbuf; 728 v->iov_len = l; 729 } else { 730 v->iov_base = f->f_prevline; 731 v->iov_len = f->f_prevlen; 732 } 733 v++; 734 735 dprintf("Logging to %s", TypeNames[f->f_type]); 736 f->f_time = now; 737 738 switch (f->f_type) { 739 case F_UNUSED: 740 dprintf("\n"); 741 break; 742 743 case F_FORW: 744 dprintf(" %s\n", f->f_un.f_forw.f_hname); 745 if ((l = snprintf(line, sizeof(line), "<%d>%.15s %s", 746 f->f_prevpri, (char *)iov[0].iov_base, 747 (char *)iov[4].iov_base)) >= sizeof(line) || l == -1) 748 l = strlen(line); 749 if (sendto(finet, line, l, 0, 750 (struct sockaddr *)&f->f_un.f_forw.f_addr, 751 sizeof(f->f_un.f_forw.f_addr)) != l) { 752 f->f_type = F_UNUSED; 753 logerror("sendto"); 754 } 755 break; 756 757 case F_CONSOLE: 758 if (flags & IGN_CONS) { 759 dprintf(" (ignored)\n"); 760 break; 761 } 762 /* FALLTHROUGH */ 763 764 case F_TTY: 765 case F_FILE: 766 dprintf(" %s\n", f->f_un.f_fname); 767 if (f->f_type != F_FILE) { 768 v->iov_base = "\r\n"; 769 v->iov_len = 2; 770 } else { 771 v->iov_base = "\n"; 772 v->iov_len = 1; 773 } 774 again: 775 if (writev(f->f_file, iov, 6) < 0) { 776 int e = errno; 777 (void)close(f->f_file); 778 /* 779 * Check for errors on TTY's due to loss of tty 780 */ 781 if (e == EAGAIN) { 782 /* 783 * Silently drop messages on blocked write. 784 * This can happen when logging to a locked tty. 785 */ 786 break; 787 } else if ((e == EIO || e == EBADF) && 788 f->f_type != F_FILE) { 789 f->f_file = open(f->f_un.f_fname, 790 O_WRONLY|O_APPEND|O_NONBLOCK, 0); 791 if (f->f_file < 0) { 792 f->f_type = F_UNUSED; 793 logerror(f->f_un.f_fname); 794 } else 795 goto again; 796 } else { 797 f->f_type = F_UNUSED; 798 f->f_file = -1; 799 errno = e; 800 logerror(f->f_un.f_fname); 801 } 802 } else if (flags & SYNC_FILE) 803 (void)fsync(f->f_file); 804 break; 805 806 case F_USERS: 807 case F_WALL: 808 dprintf("\n"); 809 v->iov_base = "\r\n"; 810 v->iov_len = 2; 811 wallmsg(f, iov); 812 break; 813 } 814 f->f_prevcount = 0; 815 } 816 817 /* 818 * WALLMSG -- Write a message to the world at large 819 * 820 * Write the specified message to either the entire 821 * world, or a list of approved users. 822 */ 823 void 824 wallmsg(struct filed *f, struct iovec *iov) 825 { 826 struct utmp ut; 827 char line[sizeof(ut.ut_line) + 1], *p; 828 static int reenter; /* avoid calling ourselves */ 829 FILE *uf; 830 int i; 831 832 if (reenter++) 833 return; 834 if ((uf = fopen(_PATH_UTMP, "r")) == NULL) { 835 logerror(_PATH_UTMP); 836 reenter = 0; 837 return; 838 } 839 /* NOSTRICT */ 840 while (fread((char *)&ut, sizeof(ut), 1, uf) == 1) { 841 if (ut.ut_name[0] == '\0') 842 continue; 843 strlcpy(line, ut.ut_line, sizeof(line)); 844 if (f->f_type == F_WALL) { 845 if ((p = ttymsg(iov, 6, line, TTYMSGTIME)) != NULL) { 846 errno = 0; /* already in msg */ 847 logerror(p); 848 } 849 continue; 850 } 851 /* should we send the message to this user? */ 852 for (i = 0; i < MAXUNAMES; i++) { 853 if (!f->f_un.f_uname[i][0]) 854 break; 855 if (!strncmp(f->f_un.f_uname[i], ut.ut_name, 856 UT_NAMESIZE)) { 857 if ((p = ttymsg(iov, 6, line, TTYMSGTIME)) 858 != NULL) { 859 errno = 0; /* already in msg */ 860 logerror(p); 861 } 862 break; 863 } 864 } 865 } 866 (void)fclose(uf); 867 reenter = 0; 868 } 869 870 void 871 reapchild(int signo) 872 { 873 int save_errno = errno; 874 int status; 875 876 while (waitpid(-1, &status, WNOHANG) > 0) 877 ; 878 errno = save_errno; 879 } 880 881 /* 882 * Return a printable representation of a host address. 883 */ 884 char * 885 cvthname(struct sockaddr_in *f) 886 { 887 struct hostent *hp; 888 sigset_t omask, nmask; 889 char *p; 890 char *ip; 891 892 if (f->sin_family != AF_INET) { 893 dprintf("Malformed from address\n"); 894 return ("???"); 895 } 896 897 ip = inet_ntoa(f->sin_addr); 898 dprintf("cvthname(%s)\n", ip); 899 if (NoDNS) 900 return (ip); 901 902 sigemptyset(&nmask); 903 sigaddset(&nmask, SIGHUP); 904 sigprocmask(SIG_BLOCK, &nmask, &omask); 905 hp = gethostbyaddr((char *)&f->sin_addr, 906 sizeof(struct in_addr), f->sin_family); 907 sigprocmask(SIG_SETMASK, &omask, NULL); 908 if (hp == 0) { 909 dprintf("Host name for your address (%s) unknown\n", ip); 910 return (ip); 911 } 912 if ((p = strchr(hp->h_name, '.')) && strcmp(p + 1, LocalDomain) == 0) 913 *p = '\0'; 914 return (hp->h_name); 915 } 916 917 void 918 dodie(int signo) 919 { 920 WantDie = signo; 921 } 922 923 void 924 domark(int signo) 925 { 926 MarkSet = 1; 927 } 928 929 void 930 doinit(int signo) 931 { 932 DoInit = 1; 933 } 934 935 /* 936 * Print syslogd errors some place. 937 */ 938 void 939 logerror(char *type) 940 { 941 char buf[100]; 942 943 if (errno) 944 (void)snprintf(buf, sizeof(buf), "syslogd: %s: %s", 945 type, strerror(errno)); 946 else 947 (void)snprintf(buf, sizeof(buf), "syslogd: %s", type); 948 errno = 0; 949 dprintf("%s\n", buf); 950 logmsg(LOG_SYSLOG|LOG_ERR, buf, LocalHostName, ADDDATE); 951 } 952 953 void 954 die(int signo) 955 { 956 struct filed *f; 957 int was_initialized = Initialized; 958 char buf[100]; 959 int i; 960 961 Initialized = 0; /* Don't log SIGCHLDs */ 962 alarm(0); 963 for (f = Files; f != NULL; f = f->f_next) { 964 /* flush any pending output */ 965 if (f->f_prevcount) 966 fprintlog(f, 0, (char *)NULL); 967 } 968 Initialized = was_initialized; 969 if (signo) { 970 dprintf("syslogd: exiting on signal %d\n", signo); 971 (void)snprintf(buf, sizeof buf, "exiting on signal %d", signo); 972 errno = 0; 973 logerror(buf); 974 } 975 for (i = 0; i < nfunix; i++) 976 if (funixn[i] && funix[i] != -1) 977 (void)unlink(funixn[i]); 978 exit(0); 979 } 980 981 /* 982 * INIT -- Initialize syslogd from configuration table 983 */ 984 void 985 init(void) 986 { 987 char cline[LINE_MAX], prog[NAME_MAX+1], *p; 988 struct filed *f, *next, **nextp; 989 FILE *cf; 990 int i; 991 992 dprintf("init\n"); 993 994 /* 995 * Close all open log files. 996 */ 997 Initialized = 0; 998 for (f = Files; f != NULL; f = next) { 999 /* flush any pending output */ 1000 if (f->f_prevcount) 1001 fprintlog(f, 0, (char *)NULL); 1002 1003 switch (f->f_type) { 1004 case F_FILE: 1005 case F_TTY: 1006 case F_CONSOLE: 1007 (void)close(f->f_file); 1008 break; 1009 case F_FORW: 1010 break; 1011 } 1012 next = f->f_next; 1013 if (f->f_program) 1014 free(f->f_program); 1015 free((char *)f); 1016 } 1017 Files = NULL; 1018 nextp = &Files; 1019 1020 /* open the configuration file */ 1021 if ((cf = fopen(ConfFile, "r")) == NULL) { 1022 dprintf("cannot open %s\n", ConfFile); 1023 *nextp = (struct filed *)calloc(1, sizeof(*f)); 1024 cfline("*.ERR\t/dev/console", *nextp, "*"); 1025 (*nextp)->f_next = (struct filed *)calloc(1, sizeof(*f)); 1026 cfline("*.PANIC\t*", (*nextp)->f_next, "*"); 1027 Initialized = 1; 1028 return; 1029 } 1030 1031 /* 1032 * Foreach line in the conf table, open that file. 1033 */ 1034 f = NULL; 1035 strlcpy(prog, "*", sizeof(prog)); 1036 while (fgets(cline, sizeof(cline), cf) != NULL) { 1037 /* 1038 * check for end-of-section, comments, strip off trailing 1039 * spaces and newline character. !prog is treated 1040 * specially: the following lines apply only to that program. 1041 */ 1042 for (p = cline; isspace(*p); ++p) 1043 continue; 1044 if (*p == '\0' || *p == '#') 1045 continue; 1046 if (*p == '!') { 1047 p++; 1048 while (isspace(*p)) 1049 p++; 1050 if (!*p) { 1051 strlcpy(prog, "*", sizeof(prog)); 1052 continue; 1053 } 1054 for (i = 0; i < NAME_MAX; i++) { 1055 if (!isalnum(p[i])) 1056 break; 1057 prog[i] = p[i]; 1058 } 1059 prog[i] = 0; 1060 continue; 1061 } 1062 p = cline + strlen(cline); 1063 while (p > cline) 1064 if (!isspace(*--p)) { 1065 p++; 1066 break; 1067 } 1068 *p = '\0'; 1069 f = (struct filed *)calloc(1, sizeof(*f)); 1070 *nextp = f; 1071 nextp = &f->f_next; 1072 cfline(cline, f, prog); 1073 } 1074 1075 /* close the configuration file */ 1076 (void)fclose(cf); 1077 1078 Initialized = 1; 1079 1080 if (Debug) { 1081 for (f = Files; f; f = f->f_next) { 1082 for (i = 0; i <= LOG_NFACILITIES; i++) 1083 if (f->f_pmask[i] == INTERNAL_NOPRI) 1084 printf("X "); 1085 else 1086 printf("%d ", f->f_pmask[i]); 1087 printf("%s: ", TypeNames[f->f_type]); 1088 switch (f->f_type) { 1089 case F_FILE: 1090 case F_TTY: 1091 case F_CONSOLE: 1092 printf("%s", f->f_un.f_fname); 1093 break; 1094 1095 case F_FORW: 1096 printf("%s", f->f_un.f_forw.f_hname); 1097 break; 1098 1099 case F_USERS: 1100 for (i = 0; i < MAXUNAMES && *f->f_un.f_uname[i]; i++) 1101 printf("%s, ", f->f_un.f_uname[i]); 1102 break; 1103 } 1104 if (f->f_program) 1105 printf(" (%s)", f->f_program); 1106 printf("\n"); 1107 } 1108 } 1109 1110 logmsg(LOG_SYSLOG|LOG_INFO, "syslogd: restart", LocalHostName, 1111 ADDDATE); 1112 dprintf("syslogd: restarted\n"); 1113 } 1114 1115 /* 1116 * Crack a configuration file line 1117 */ 1118 void 1119 cfline(char *line, struct filed *f, char *prog) 1120 { 1121 struct hostent *hp; 1122 int i, pri; 1123 char *bp, *p, *q; 1124 char buf[MAXLINE], ebuf[100]; 1125 1126 dprintf("cfline(\"%s\", f, \"%s\")\n", line, prog); 1127 1128 errno = 0; /* keep strerror() stuff out of logerror messages */ 1129 1130 /* clear out file entry */ 1131 memset(f, 0, sizeof(*f)); 1132 for (i = 0; i <= LOG_NFACILITIES; i++) 1133 f->f_pmask[i] = INTERNAL_NOPRI; 1134 1135 /* save program name if any */ 1136 if (!strcmp(prog, "*")) 1137 prog = NULL; 1138 else { 1139 f->f_program = calloc(1, strlen(prog)+1); 1140 if (f->f_program) 1141 strlcpy(f->f_program, prog, strlen(prog)+1); 1142 } 1143 1144 /* scan through the list of selectors */ 1145 for (p = line; *p && *p != '\t';) { 1146 1147 /* find the end of this facility name list */ 1148 for (q = p; *q && *q != '\t' && *q++ != '.'; ) 1149 continue; 1150 1151 /* collect priority name */ 1152 for (bp = buf; *q && !strchr("\t,;", *q); ) 1153 *bp++ = *q++; 1154 *bp = '\0'; 1155 1156 /* skip cruft */ 1157 while (strchr(", ;", *q)) 1158 q++; 1159 1160 /* decode priority name */ 1161 if (*buf == '*') 1162 pri = LOG_PRIMASK + 1; 1163 else { 1164 /* ignore trailing spaces */ 1165 int i; 1166 for (i=strlen(buf)-1; i >= 0 && buf[i] == ' '; i--) { 1167 buf[i]='\0'; 1168 } 1169 1170 pri = decode(buf, prioritynames); 1171 if (pri < 0) { 1172 (void)snprintf(ebuf, sizeof ebuf, 1173 "unknown priority name \"%s\"", buf); 1174 logerror(ebuf); 1175 return; 1176 } 1177 } 1178 1179 /* scan facilities */ 1180 while (*p && !strchr("\t.;", *p)) { 1181 for (bp = buf; *p && !strchr("\t,;.", *p); ) 1182 *bp++ = *p++; 1183 *bp = '\0'; 1184 if (*buf == '*') 1185 for (i = 0; i < LOG_NFACILITIES; i++) 1186 f->f_pmask[i] = pri; 1187 else { 1188 i = decode(buf, facilitynames); 1189 if (i < 0) { 1190 (void)snprintf(ebuf, sizeof(ebuf), 1191 "unknown facility name \"%s\"", 1192 buf); 1193 logerror(ebuf); 1194 return; 1195 } 1196 f->f_pmask[i >> 3] = pri; 1197 } 1198 while (*p == ',' || *p == ' ') 1199 p++; 1200 } 1201 1202 p = q; 1203 } 1204 1205 /* skip to action part */ 1206 while (*p == '\t') 1207 p++; 1208 1209 switch (*p) { 1210 case '@': 1211 if (!InetInuse) 1212 break; 1213 (void)strlcpy(f->f_un.f_forw.f_hname, ++p, 1214 sizeof(f->f_un.f_forw.f_hname)); 1215 hp = gethostbyname(f->f_un.f_forw.f_hname); 1216 if (hp == NULL) { 1217 extern int h_errno; 1218 1219 logerror((char *)hstrerror(h_errno)); 1220 break; 1221 } 1222 memset(&f->f_un.f_forw.f_addr, 0, 1223 sizeof(f->f_un.f_forw.f_addr)); 1224 f->f_un.f_forw.f_addr.sin_len = sizeof(f->f_un.f_forw.f_addr); 1225 f->f_un.f_forw.f_addr.sin_family = AF_INET; 1226 f->f_un.f_forw.f_addr.sin_port = LogPort; 1227 memmove(&f->f_un.f_forw.f_addr.sin_addr, hp->h_addr, 1228 hp->h_length); 1229 f->f_type = F_FORW; 1230 break; 1231 1232 case '/': 1233 (void)strlcpy(f->f_un.f_fname, p, sizeof(f->f_un.f_fname)); 1234 f->f_file = open(p, O_WRONLY|O_APPEND|O_NONBLOCK, 0); 1235 if (f->f_file < 0) { 1236 f->f_type = F_UNUSED; 1237 logerror(p); 1238 break; 1239 } 1240 if (isatty(f->f_file)) { 1241 if (strcmp(p, ctty) == 0) 1242 f->f_type = F_CONSOLE; 1243 else 1244 f->f_type = F_TTY; 1245 } else { 1246 f->f_type = F_FILE; 1247 /* Clear O_NONBLOCK flag on f->f_file */ 1248 if ((i = fcntl(f->f_file, F_GETFL, 0)) != -1) { 1249 i &= ~O_NONBLOCK; 1250 fcntl(f->f_file, F_SETFL, i); 1251 } 1252 } 1253 break; 1254 1255 case '*': 1256 f->f_type = F_WALL; 1257 break; 1258 1259 default: 1260 for (i = 0; i < MAXUNAMES && *p; i++) { 1261 for (q = p; *q && *q != ','; ) 1262 q++; 1263 (void)strncpy(f->f_un.f_uname[i], p, UT_NAMESIZE); 1264 if ((q - p) > UT_NAMESIZE) 1265 f->f_un.f_uname[i][UT_NAMESIZE] = '\0'; 1266 else 1267 f->f_un.f_uname[i][q - p] = '\0'; 1268 while (*q == ',' || *q == ' ') 1269 q++; 1270 p = q; 1271 } 1272 f->f_type = F_USERS; 1273 break; 1274 } 1275 } 1276 1277 1278 /* 1279 * Retrieve the size of the kernel message buffer, via sysctl. 1280 */ 1281 int 1282 getmsgbufsize(void) 1283 { 1284 int msgbufsize, mib[2]; 1285 size_t size; 1286 1287 mib[0] = CTL_KERN; 1288 mib[1] = KERN_MSGBUFSIZE; 1289 size = sizeof msgbufsize; 1290 if (sysctl(mib, 2, &msgbufsize, &size, NULL, 0) == -1) { 1291 dprintf("couldn't get kern.msgbufsize\n"); 1292 return (0); 1293 } 1294 return (msgbufsize); 1295 } 1296 1297 /* 1298 * Decode a symbolic name to a numeric value 1299 */ 1300 int 1301 decode(const char *name, CODE *codetab) 1302 { 1303 CODE *c; 1304 char *p, buf[40]; 1305 1306 if (isdigit(*name)) 1307 return (atoi(name)); 1308 1309 for (p = buf; *name && p < &buf[sizeof(buf) - 1]; p++, name++) { 1310 if (isupper(*name)) 1311 *p = tolower(*name); 1312 else 1313 *p = *name; 1314 } 1315 *p = '\0'; 1316 for (c = codetab; c->c_name; c++) 1317 if (!strcmp(buf, c->c_name)) 1318 return (c->c_val); 1319 1320 return (-1); 1321 } 1322 1323 void 1324 markit(void) 1325 { 1326 struct filed *f; 1327 1328 now = time((time_t *)NULL); 1329 MarkSeq += TIMERINTVL; 1330 if (MarkSeq >= MarkInterval) { 1331 logmsg(LOG_INFO, "-- MARK --", 1332 LocalHostName, ADDDATE|MARK); 1333 MarkSeq = 0; 1334 } 1335 1336 for (f = Files; f; f = f->f_next) { 1337 if (f->f_prevcount && now >= REPEATTIME(f)) { 1338 dprintf("flush %s: repeated %d times, %d sec.\n", 1339 TypeNames[f->f_type], f->f_prevcount, 1340 repeatinterval[f->f_repeatcount]); 1341 fprintlog(f, 0, (char *)NULL); 1342 BACKOFF(f); 1343 } 1344 } 1345 MarkSet = 0; 1346 (void)alarm(TIMERINTVL); 1347 } 1348