1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1988, 1992 The University of Utah and the Center 5 * for Software Science (CSS). 6 * Copyright (c) 1992, 1993 7 * The Regents of the University of California. All rights reserved. 8 * 9 * This code is derived from software contributed to Berkeley by 10 * the Center for Software Science of the University of Utah Computer 11 * Science Department. CSS requests users of this software to return 12 * to css-dist@cs.utah.edu any improvements that they make and grant 13 * CSS redistribution rights. 14 * 15 * Redistribution and use in source and binary forms, with or without 16 * modification, are permitted provided that the following conditions 17 * are met: 18 * 1. Redistributions of source code must retain the above copyright 19 * notice, this list of conditions and the following disclaimer. 20 * 2. Redistributions in binary form must reproduce the above copyright 21 * notice, this list of conditions and the following disclaimer in the 22 * documentation and/or other materials provided with the distribution. 23 * 3. Neither the name of the University nor the names of its contributors 24 * may be used to endorse or promote products derived from this software 25 * without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 37 * SUCH DAMAGE. 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 #endif /* not lint */ 51 #include <sys/cdefs.h> 52 #include <sys/param.h> 53 #include <sys/time.h> 54 #include <ctype.h> 55 #include <err.h> 56 #include <errno.h> 57 #include <fcntl.h> 58 #include <signal.h> 59 #include <stdio.h> 60 #include <stdlib.h> 61 #include <string.h> 62 #include <syslog.h> 63 #include <unistd.h> 64 #include "defs.h" 65 66 static void usage(void) __dead2; 67 68 int 69 main(int argc, char *argv[]) 70 { 71 int c, fd, omask, maxfds; 72 fd_set rset; 73 74 /* 75 * Close any open file descriptors. 76 * Temporarily leave stdin & stdout open for `-d', 77 * and stderr open for any pre-syslog error messages. 78 */ 79 { 80 int i, nfds = getdtablesize(); 81 82 for (i = 0; i < nfds; i++) 83 if (i != fileno(stdin) && i != fileno(stdout) && 84 i != fileno(stderr)) 85 (void) close(i); 86 } 87 88 /* 89 * Parse any arguments. 90 */ 91 while ((c = getopt(argc, argv, "adi:")) != -1) 92 switch(c) { 93 case 'a': 94 BootAny++; 95 break; 96 case 'd': 97 DebugFlg++; 98 break; 99 case 'i': 100 IntfName = optarg; 101 break; 102 default: 103 usage(); 104 } 105 for (; optind < argc; optind++) { 106 if (ConfigFile == NULL) 107 ConfigFile = argv[optind]; 108 else { 109 warnx("too many config files (`%s' ignored)", 110 argv[optind]); 111 } 112 } 113 114 if (ConfigFile == NULL) /* use default config file */ 115 ConfigFile = DfltConfig; 116 117 if (DebugFlg) { 118 DbgFp = stdout; /* output to stdout */ 119 120 (void) signal(SIGUSR1, SIG_IGN); /* dont muck w/DbgFp */ 121 (void) signal(SIGUSR2, SIG_IGN); 122 (void) fclose(stderr); /* finished with it */ 123 } else { 124 if (daemon(0, 0)) 125 err(1, "can't detach from terminal"); 126 127 (void) signal(SIGUSR1, DebugOn); 128 (void) signal(SIGUSR2, DebugOff); 129 } 130 131 openlog("rbootd", LOG_PID, LOG_DAEMON); 132 133 /* 134 * If no interface was specified, get one now. 135 * 136 * This is convoluted because we want to get the default interface 137 * name for the syslog("restarted") message. If BpfGetIntfName() 138 * runs into an error, it will return a syslog-able error message 139 * (in `errmsg') which will be displayed here. 140 */ 141 if (IntfName == NULL) { 142 char *errmsg; 143 144 if ((IntfName = BpfGetIntfName(&errmsg)) == NULL) { 145 /* Backslash to avoid trigraph '??)'. */ 146 syslog(LOG_NOTICE, "restarted (?\?)"); 147 /* BpfGetIntfName() returns safe names, using %m */ 148 syslog(LOG_ERR, "%s", errmsg); 149 Exit(0); 150 } 151 } 152 153 syslog(LOG_NOTICE, "restarted (%s)", IntfName); 154 155 (void) signal(SIGHUP, ReConfig); 156 (void) signal(SIGINT, Exit); 157 (void) signal(SIGTERM, Exit); 158 159 /* 160 * Grab our host name and pid. 161 */ 162 if (gethostname(MyHost, MAXHOSTNAMELEN - 1) < 0) { 163 syslog(LOG_ERR, "gethostname: %m"); 164 Exit(0); 165 } 166 MyHost[MAXHOSTNAMELEN - 1] = '\0'; 167 168 MyPid = getpid(); 169 170 /* 171 * Write proc's pid to a file. 172 */ 173 { 174 FILE *fp; 175 176 if ((fp = fopen(PidFile, "w")) != NULL) { 177 (void) fprintf(fp, "%d\n", (int) MyPid); 178 (void) fclose(fp); 179 } else { 180 syslog(LOG_WARNING, "fopen: failed (%s)", PidFile); 181 } 182 } 183 184 /* 185 * All boot files are relative to the boot directory, we might 186 * as well chdir() there to make life easier. 187 */ 188 if (chdir(BootDir) < 0) { 189 syslog(LOG_ERR, "chdir: %m (%s)", BootDir); 190 Exit(0); 191 } 192 193 /* 194 * Initial configuration. 195 */ 196 omask = sigblock(sigmask(SIGHUP)); /* prevent reconfig's */ 197 if (GetBootFiles() == 0) /* get list of boot files */ 198 Exit(0); 199 if (ParseConfig() == 0) /* parse config file */ 200 Exit(0); 201 202 /* 203 * Open and initialize a BPF device for the appropriate interface. 204 * If an error is encountered, a message is displayed and Exit() 205 * is called. 206 */ 207 fd = BpfOpen(); 208 209 (void) sigsetmask(omask); /* allow reconfig's */ 210 211 /* 212 * Main loop: receive a packet, determine where it came from, 213 * and if we service this host, call routine to handle request. 214 */ 215 maxfds = fd + 1; 216 FD_ZERO(&rset); 217 FD_SET(fd, &rset); 218 for (;;) { 219 struct timeval timeout; 220 fd_set r; 221 int nsel; 222 223 r = rset; 224 225 if (RmpConns == NULL) { /* timeout isn't necessary */ 226 nsel = select(maxfds, &r, NULL, NULL, NULL); 227 } else { 228 timeout.tv_sec = RMP_TIMEOUT; 229 timeout.tv_usec = 0; 230 nsel = select(maxfds, &r, NULL, NULL, &timeout); 231 } 232 233 if (nsel < 0) { 234 if (errno == EINTR) 235 continue; 236 syslog(LOG_ERR, "select: %m"); 237 Exit(0); 238 } else if (nsel == 0) { /* timeout */ 239 DoTimeout(); /* clear stale conns */ 240 continue; 241 } 242 243 if (FD_ISSET(fd, &r)) { 244 RMPCONN rconn; 245 CLIENT *client; 246 int doread = 1; 247 248 while (BpfRead(&rconn, doread)) { 249 doread = 0; 250 251 if (DbgFp != NULL) /* display packet */ 252 DispPkt(&rconn,DIR_RCVD); 253 254 omask = sigblock(sigmask(SIGHUP)); 255 256 /* 257 * If we do not restrict service, set the 258 * client to NULL (ProcessPacket() handles 259 * this). Otherwise, check that we can 260 * service this host; if not, log a message 261 * and ignore the packet. 262 */ 263 if (BootAny) { 264 client = NULL; 265 } else if ((client=FindClient(&rconn))==NULL) { 266 syslog(LOG_INFO, 267 "%s: boot packet ignored", 268 EnetStr(&rconn)); 269 (void) sigsetmask(omask); 270 continue; 271 } 272 273 ProcessPacket(&rconn,client); 274 275 (void) sigsetmask(omask); 276 } 277 } 278 } 279 } 280 281 static void 282 usage(void) 283 { 284 fprintf(stderr, "usage: rbootd [-ad] [-i interface] [config_file]\n"); 285 exit (1); 286 } 287 288 /* 289 ** DoTimeout -- Free any connections that have timed out. 290 ** 291 ** Parameters: 292 ** None. 293 ** 294 ** Returns: 295 ** Nothing. 296 ** 297 ** Side Effects: 298 ** - Timed out connections in `RmpConns' will be freed. 299 */ 300 void 301 DoTimeout(void) 302 { 303 RMPCONN *rtmp; 304 time_t now; 305 306 /* 307 * For each active connection, if RMP_TIMEOUT seconds have passed 308 * since the last packet was sent, delete the connection. 309 */ 310 now = time(NULL); 311 for (rtmp = RmpConns; rtmp != NULL; rtmp = rtmp->next) 312 if ((rtmp->tstamp.tv_sec + RMP_TIMEOUT) < now) { 313 syslog(LOG_WARNING, "%s: connection timed out (%u)", 314 EnetStr(rtmp), rtmp->rmp.r_type); 315 RemoveConn(rtmp); 316 } 317 } 318 319 /* 320 ** FindClient -- Find client associated with a packet. 321 ** 322 ** Parameters: 323 ** rconn - the new packet. 324 ** 325 ** Returns: 326 ** Pointer to client info if found, NULL otherwise. 327 ** 328 ** Side Effects: 329 ** None. 330 ** 331 ** Warnings: 332 ** - This routine must be called with SIGHUP blocked since 333 ** a reconfigure can invalidate the information returned. 334 */ 335 336 CLIENT * 337 FindClient(RMPCONN *rconn) 338 { 339 CLIENT *ctmp; 340 341 for (ctmp = Clients; ctmp != NULL; ctmp = ctmp->next) 342 if (bcmp((char *)&rconn->rmp.hp_hdr.saddr[0], 343 (char *)&ctmp->addr[0], RMP_ADDRLEN) == 0) 344 break; 345 346 return(ctmp); 347 } 348 349 /* 350 ** Exit -- Log an error message and exit. 351 ** 352 ** Parameters: 353 ** sig - caught signal (or zero if not dying on a signal). 354 ** 355 ** Returns: 356 ** Does not return. 357 ** 358 ** Side Effects: 359 ** - This process ceases to exist. 360 */ 361 void 362 Exit(int sig) 363 { 364 if (sig > 0) 365 syslog(LOG_ERR, "going down on signal %d", sig); 366 else 367 syslog(LOG_ERR, "going down with fatal error"); 368 BpfClose(); 369 exit(1); 370 } 371 372 /* 373 ** ReConfig -- Get new list of boot files and reread config files. 374 ** 375 ** Parameters: 376 ** None. 377 ** 378 ** Returns: 379 ** Nothing. 380 ** 381 ** Side Effects: 382 ** - All active connections are dropped. 383 ** - List of boot-able files is changed. 384 ** - List of clients is changed. 385 ** 386 ** Warnings: 387 ** - This routine must be called with SIGHUP blocked. 388 */ 389 void 390 ReConfig(int signo __unused) 391 { 392 syslog(LOG_NOTICE, "reconfiguring boot server"); 393 394 FreeConns(); 395 396 if (GetBootFiles() == 0) 397 Exit(0); 398 399 if (ParseConfig() == 0) 400 Exit(0); 401 } 402 403 /* 404 ** DebugOff -- Turn off debugging. 405 ** 406 ** Parameters: 407 ** None. 408 ** 409 ** Returns: 410 ** Nothing. 411 ** 412 ** Side Effects: 413 ** - Debug file is closed. 414 */ 415 void 416 DebugOff(int signo __unused) 417 { 418 if (DbgFp != NULL) 419 (void) fclose(DbgFp); 420 421 DbgFp = NULL; 422 } 423 424 /* 425 ** DebugOn -- Turn on debugging. 426 ** 427 ** Parameters: 428 ** None. 429 ** 430 ** Returns: 431 ** Nothing. 432 ** 433 ** Side Effects: 434 ** - Debug file is opened/truncated if not already opened, 435 ** otherwise do nothing. 436 */ 437 void 438 DebugOn(int signo __unused) 439 { 440 if (DbgFp == NULL) { 441 if ((DbgFp = fopen(DbgFile, "w")) == NULL) 442 syslog(LOG_ERR, "can't open debug file (%s)", DbgFile); 443 } 444 } 445