1 /* 2 * Copyright (c) 1988, 1992 The University of Utah and the Center 3 * for Software Science (CSS). 4 * Copyright (c) 1992, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * the Center for Software Science of the University of Utah Computer 9 * Science Department. CSS requests users of this software to return 10 * to css-dist@cs.utah.edu any improvements that they make and grant 11 * CSS redistribution rights. 12 * 13 * Redistribution and use in source and binary forms, with or without 14 * modification, are permitted provided that the following conditions 15 * are met: 16 * 1. Redistributions of source code must retain the above copyright 17 * notice, this list of conditions and the following disclaimer. 18 * 2. Redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution. 21 * 3. Neither the name of the University nor the names of its contributors 22 * may be used to endorse or promote products derived from this software 23 * without specific prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 35 * SUCH DAMAGE. 36 * 37 * from: @(#)rbootd.c 8.1 (Berkeley) 6/4/93 38 * 39 * From: Utah Hdr: rbootd.c 3.1 92/07/06 40 * Author: Jeff Forys, University of Utah CSS 41 */ 42 43 #ifndef lint 44 static const char copyright[] = 45 "@(#) Copyright (c) 1992, 1993\n\ 46 The Regents of the University of California. All rights reserved.\n"; 47 #endif /* not lint */ 48 49 #ifndef lint 50 #if 0 51 static const char sccsid[] = "@(#)rbootd.c 8.1 (Berkeley) 6/4/93"; 52 #endif 53 #endif /* not lint */ 54 #include <sys/cdefs.h> 55 __FBSDID("$FreeBSD$"); 56 57 #include <sys/param.h> 58 #include <sys/time.h> 59 #include <ctype.h> 60 #include <err.h> 61 #include <errno.h> 62 #include <fcntl.h> 63 #include <signal.h> 64 #include <stdio.h> 65 #include <stdlib.h> 66 #include <string.h> 67 #include <syslog.h> 68 #include <unistd.h> 69 #include "defs.h" 70 71 static void usage(void); 72 73 int 74 main(int argc, char *argv[]) 75 { 76 int c, fd, omask, maxfds; 77 fd_set rset; 78 79 /* 80 * Close any open file descriptors. 81 * Temporarily leave stdin & stdout open for `-d', 82 * and stderr open for any pre-syslog error messages. 83 */ 84 { 85 int i, nfds = getdtablesize(); 86 87 for (i = 0; i < nfds; i++) 88 if (i != fileno(stdin) && i != fileno(stdout) && 89 i != fileno(stderr)) 90 (void) close(i); 91 } 92 93 /* 94 * Parse any arguments. 95 */ 96 while ((c = getopt(argc, argv, "adi:")) != -1) 97 switch(c) { 98 case 'a': 99 BootAny++; 100 break; 101 case 'd': 102 DebugFlg++; 103 break; 104 case 'i': 105 IntfName = optarg; 106 break; 107 default: 108 usage(); 109 } 110 for (; optind < argc; optind++) { 111 if (ConfigFile == NULL) 112 ConfigFile = argv[optind]; 113 else { 114 warnx("too many config files (`%s' ignored)", 115 argv[optind]); 116 } 117 } 118 119 if (ConfigFile == NULL) /* use default config file */ 120 ConfigFile = DfltConfig; 121 122 if (DebugFlg) { 123 DbgFp = stdout; /* output to stdout */ 124 125 (void) signal(SIGUSR1, SIG_IGN); /* dont muck w/DbgFp */ 126 (void) signal(SIGUSR2, SIG_IGN); 127 (void) fclose(stderr); /* finished with it */ 128 } else { 129 if (daemon(0, 0)) 130 err(1, "can't detach from terminal"); 131 132 (void) signal(SIGUSR1, DebugOn); 133 (void) signal(SIGUSR2, DebugOff); 134 } 135 136 openlog("rbootd", LOG_PID, LOG_DAEMON); 137 138 /* 139 * If no interface was specified, get one now. 140 * 141 * This is convoluted because we want to get the default interface 142 * name for the syslog("restarted") message. If BpfGetIntfName() 143 * runs into an error, it will return a syslog-able error message 144 * (in `errmsg') which will be displayed here. 145 */ 146 if (IntfName == NULL) { 147 char *errmsg; 148 149 if ((IntfName = BpfGetIntfName(&errmsg)) == NULL) { 150 /* Backslash to avoid trigraph '??)'. */ 151 syslog(LOG_NOTICE, "restarted (?\?)"); 152 /* BpfGetIntfName() returns safe names, using %m */ 153 syslog(LOG_ERR, "%s", errmsg); 154 Exit(0); 155 } 156 } 157 158 syslog(LOG_NOTICE, "restarted (%s)", IntfName); 159 160 (void) signal(SIGHUP, ReConfig); 161 (void) signal(SIGINT, Exit); 162 (void) signal(SIGTERM, Exit); 163 164 /* 165 * Grab our host name and pid. 166 */ 167 if (gethostname(MyHost, MAXHOSTNAMELEN - 1) < 0) { 168 syslog(LOG_ERR, "gethostname: %m"); 169 Exit(0); 170 } 171 MyHost[MAXHOSTNAMELEN - 1] = '\0'; 172 173 MyPid = getpid(); 174 175 /* 176 * Write proc's pid to a file. 177 */ 178 { 179 FILE *fp; 180 181 if ((fp = fopen(PidFile, "w")) != NULL) { 182 (void) fprintf(fp, "%d\n", (int) MyPid); 183 (void) fclose(fp); 184 } else { 185 syslog(LOG_WARNING, "fopen: failed (%s)", PidFile); 186 } 187 } 188 189 /* 190 * All boot files are relative to the boot directory, we might 191 * as well chdir() there to make life easier. 192 */ 193 if (chdir(BootDir) < 0) { 194 syslog(LOG_ERR, "chdir: %m (%s)", BootDir); 195 Exit(0); 196 } 197 198 /* 199 * Initial configuration. 200 */ 201 omask = sigblock(sigmask(SIGHUP)); /* prevent reconfig's */ 202 if (GetBootFiles() == 0) /* get list of boot files */ 203 Exit(0); 204 if (ParseConfig() == 0) /* parse config file */ 205 Exit(0); 206 207 /* 208 * Open and initialize a BPF device for the appropriate interface. 209 * If an error is encountered, a message is displayed and Exit() 210 * is called. 211 */ 212 fd = BpfOpen(); 213 214 (void) sigsetmask(omask); /* allow reconfig's */ 215 216 /* 217 * Main loop: receive a packet, determine where it came from, 218 * and if we service this host, call routine to handle request. 219 */ 220 maxfds = fd + 1; 221 FD_ZERO(&rset); 222 FD_SET(fd, &rset); 223 for (;;) { 224 struct timeval timeout; 225 fd_set r; 226 int nsel; 227 228 r = rset; 229 230 if (RmpConns == NULL) { /* timeout isn't necessary */ 231 nsel = select(maxfds, &r, NULL, NULL, NULL); 232 } else { 233 timeout.tv_sec = RMP_TIMEOUT; 234 timeout.tv_usec = 0; 235 nsel = select(maxfds, &r, NULL, NULL, &timeout); 236 } 237 238 if (nsel < 0) { 239 if (errno == EINTR) 240 continue; 241 syslog(LOG_ERR, "select: %m"); 242 Exit(0); 243 } else if (nsel == 0) { /* timeout */ 244 DoTimeout(); /* clear stale conns */ 245 continue; 246 } 247 248 if (FD_ISSET(fd, &r)) { 249 RMPCONN rconn; 250 CLIENT *client, *FindClient(); 251 int doread = 1; 252 253 while (BpfRead(&rconn, doread)) { 254 doread = 0; 255 256 if (DbgFp != NULL) /* display packet */ 257 DispPkt(&rconn,DIR_RCVD); 258 259 omask = sigblock(sigmask(SIGHUP)); 260 261 /* 262 * If we do not restrict service, set the 263 * client to NULL (ProcessPacket() handles 264 * this). Otherwise, check that we can 265 * service this host; if not, log a message 266 * and ignore the packet. 267 */ 268 if (BootAny) { 269 client = NULL; 270 } else if ((client=FindClient(&rconn))==NULL) { 271 syslog(LOG_INFO, 272 "%s: boot packet ignored", 273 EnetStr(&rconn)); 274 (void) sigsetmask(omask); 275 continue; 276 } 277 278 ProcessPacket(&rconn,client); 279 280 (void) sigsetmask(omask); 281 } 282 } 283 } 284 } 285 286 static void 287 usage(void) 288 { 289 fprintf(stderr, "usage: rbootd [-ad] [-i interface] [config_file]\n"); 290 exit (1); 291 } 292 293 /* 294 ** DoTimeout -- Free any connections that have timed out. 295 ** 296 ** Parameters: 297 ** None. 298 ** 299 ** Returns: 300 ** Nothing. 301 ** 302 ** Side Effects: 303 ** - Timed out connections in `RmpConns' will be freed. 304 */ 305 void 306 DoTimeout(void) 307 { 308 RMPCONN *rtmp; 309 time_t now; 310 311 /* 312 * For each active connection, if RMP_TIMEOUT seconds have passed 313 * since the last packet was sent, delete the connection. 314 */ 315 now = time(NULL); 316 for (rtmp = RmpConns; rtmp != NULL; rtmp = rtmp->next) 317 if ((rtmp->tstamp.tv_sec + RMP_TIMEOUT) < now) { 318 syslog(LOG_WARNING, "%s: connection timed out (%u)", 319 EnetStr(rtmp), rtmp->rmp.r_type); 320 RemoveConn(rtmp); 321 } 322 } 323 324 /* 325 ** FindClient -- Find client associated with a packet. 326 ** 327 ** Parameters: 328 ** rconn - the new packet. 329 ** 330 ** Returns: 331 ** Pointer to client info if found, NULL otherwise. 332 ** 333 ** Side Effects: 334 ** None. 335 ** 336 ** Warnings: 337 ** - This routine must be called with SIGHUP blocked since 338 ** a reconfigure can invalidate the information returned. 339 */ 340 341 CLIENT * 342 FindClient(RMPCONN *rconn) 343 { 344 CLIENT *ctmp; 345 346 for (ctmp = Clients; ctmp != NULL; ctmp = ctmp->next) 347 if (bcmp((char *)&rconn->rmp.hp_hdr.saddr[0], 348 (char *)&ctmp->addr[0], RMP_ADDRLEN) == 0) 349 break; 350 351 return(ctmp); 352 } 353 354 /* 355 ** Exit -- Log an error message and exit. 356 ** 357 ** Parameters: 358 ** sig - caught signal (or zero if not dying on a signal). 359 ** 360 ** Returns: 361 ** Does not return. 362 ** 363 ** Side Effects: 364 ** - This process ceases to exist. 365 */ 366 void 367 Exit(int sig) 368 { 369 if (sig > 0) 370 syslog(LOG_ERR, "going down on signal %d", sig); 371 else 372 syslog(LOG_ERR, "going down with fatal error"); 373 BpfClose(); 374 exit(1); 375 } 376 377 /* 378 ** ReConfig -- Get new list of boot files and reread config files. 379 ** 380 ** Parameters: 381 ** None. 382 ** 383 ** Returns: 384 ** Nothing. 385 ** 386 ** Side Effects: 387 ** - All active connections are dropped. 388 ** - List of boot-able files is changed. 389 ** - List of clients is changed. 390 ** 391 ** Warnings: 392 ** - This routine must be called with SIGHUP blocked. 393 */ 394 void 395 ReConfig(int signo __unused) 396 { 397 syslog(LOG_NOTICE, "reconfiguring boot server"); 398 399 FreeConns(); 400 401 if (GetBootFiles() == 0) 402 Exit(0); 403 404 if (ParseConfig() == 0) 405 Exit(0); 406 } 407 408 /* 409 ** DebugOff -- Turn off debugging. 410 ** 411 ** Parameters: 412 ** None. 413 ** 414 ** Returns: 415 ** Nothing. 416 ** 417 ** Side Effects: 418 ** - Debug file is closed. 419 */ 420 void 421 DebugOff(int signo __unused) 422 { 423 if (DbgFp != NULL) 424 (void) fclose(DbgFp); 425 426 DbgFp = NULL; 427 } 428 429 /* 430 ** DebugOn -- Turn on debugging. 431 ** 432 ** Parameters: 433 ** None. 434 ** 435 ** Returns: 436 ** Nothing. 437 ** 438 ** Side Effects: 439 ** - Debug file is opened/truncated if not already opened, 440 ** otherwise do nothing. 441 */ 442 void 443 DebugOn(int signo __unused) 444 { 445 if (DbgFp == NULL) { 446 if ((DbgFp = fopen(DbgFile, "w")) == NULL) 447 syslog(LOG_ERR, "can't open debug file (%s)", DbgFile); 448 } 449 } 450