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 * %sccs.include.redist.c% 14 * 15 * @(#)rbootd.c 8.1 (Berkeley) 06/04/93 16 * 17 * Utah $Hdr: rbootd.c 3.1 92/07/06$ 18 * Author: Jeff Forys, University of Utah CSS 19 */ 20 21 #ifndef lint 22 static char copyright[] = 23 "@(#) Copyright (c) 1992, 1993\n\ 24 The Regents of the University of California. All rights reserved.\n"; 25 #endif /* not lint */ 26 27 #ifndef lint 28 static char sccsid[] = "@(#)rbootd.c 8.1 (Berkeley) 06/04/93"; 29 #endif /* not lint */ 30 31 #include <sys/param.h> 32 #include <sys/ioctl.h> 33 34 #include <ctype.h> 35 #include <errno.h> 36 #include <fcntl.h> 37 #include <signal.h> 38 #include <stdio.h> 39 #include <stdlib.h> 40 #include <string.h> 41 #include <syslog.h> 42 #include <unistd.h> 43 #include "defs.h" 44 45 46 /* fd mask macros (backward compatibility with 4.2BSD) */ 47 #ifndef FD_SET 48 #ifdef notdef 49 typedef struct fd_set { /* this should already be in 4.2 */ 50 int fds_bits[1]; 51 } fd_set; 52 #endif 53 #define FD_ZERO(p) ((p)->fds_bits[0] = 0) 54 #define FD_SET(n, p) ((p)->fds_bits[0] |= (1 << (n))) 55 #define FD_CLR(n, p) ((p)->fds_bits[0] &= ~(1 << (n))) 56 #define FD_ISSET(n, p) ((p)->fds_bits[0] & (1 << (n))) 57 #endif 58 59 int 60 main(argc, argv) 61 int argc; 62 char *argv[]; 63 { 64 int c, fd, omask, maxfds; 65 fd_set rset; 66 67 /* 68 * Find what name we are running under. 69 */ 70 ProgName = (ProgName = rindex(argv[0],'/')) ? ++ProgName : *argv; 71 72 /* 73 * Close any open file descriptors. 74 * Temporarily leave stdin & stdout open for `-d', 75 * and stderr open for any pre-syslog error messages. 76 */ 77 { 78 int i, nfds = getdtablesize(); 79 80 for (i = 0; i < nfds; i++) 81 if (i != fileno(stdin) && i != fileno(stdout) && 82 i != fileno(stderr)) 83 (void) close(i); 84 } 85 86 /* 87 * Parse any arguments. 88 */ 89 while ((c = getopt(argc, argv, "adi:")) != EOF) 90 switch(c) { 91 case 'a': 92 BootAny++; 93 break; 94 case 'd': 95 DebugFlg++; 96 break; 97 case 'i': 98 IntfName = optarg; 99 break; 100 } 101 for (; optind < argc; optind++) { 102 if (ConfigFile == NULL) 103 ConfigFile = argv[optind]; 104 else { 105 fprintf(stderr, 106 "%s: too many config files (`%s' ignored)\n", 107 ProgName, argv[optind]); 108 } 109 } 110 111 if (ConfigFile == NULL) /* use default config file */ 112 ConfigFile = DfltConfig; 113 114 if (DebugFlg) { 115 DbgFp = stdout; /* output to stdout */ 116 117 (void) signal(SIGUSR1, SIG_IGN); /* dont muck w/DbgFp */ 118 (void) signal(SIGUSR2, SIG_IGN); 119 } else { 120 (void) fclose(stdin); /* dont need these */ 121 (void) fclose(stdout); 122 123 /* 124 * Fork off a child to do the work & exit. 125 */ 126 switch(fork()) { 127 case -1: /* fork failed */ 128 fprintf(stderr, "%s: ", ProgName); 129 perror("fork"); 130 Exit(0); 131 case 0: /* this is the CHILD */ 132 break; 133 default: /* this is the PARENT */ 134 _exit(0); 135 } 136 137 /* 138 * Try to disassociate from the current tty. 139 */ 140 { 141 char *devtty = "/dev/tty"; 142 int i; 143 144 if ((i = open(devtty, O_RDWR)) < 0) { 145 /* probably already disassociated */ 146 if (setpgrp(0, 0) < 0) { 147 fprintf(stderr, "%s: ", ProgName); 148 perror("setpgrp"); 149 } 150 } else { 151 if (ioctl(i, (u_long)TIOCNOTTY, (char *)0) < 0){ 152 fprintf(stderr, "%s: ", ProgName); 153 perror("ioctl"); 154 } 155 (void) close(i); 156 } 157 } 158 159 (void) signal(SIGUSR1, DebugOn); 160 (void) signal(SIGUSR2, DebugOff); 161 } 162 163 (void) fclose(stderr); /* finished with it */ 164 165 #ifdef SYSLOG4_2 166 openlog(ProgName, LOG_PID); 167 #else 168 openlog(ProgName, LOG_PID, LOG_DAEMON); 169 #endif 170 171 /* 172 * If no interface was specified, get one now. 173 * 174 * This is convoluted because we want to get the default interface 175 * name for the syslog("restarted") message. If BpfGetIntfName() 176 * runs into an error, it will return a syslog-able error message 177 * (in `errmsg') which will be displayed here. 178 */ 179 if (IntfName == NULL) { 180 char *errmsg; 181 182 if ((IntfName = BpfGetIntfName(&errmsg)) == NULL) { 183 syslog(LOG_NOTICE, "restarted (??)"); 184 syslog(LOG_ERR, errmsg); 185 Exit(0); 186 } 187 } 188 189 syslog(LOG_NOTICE, "restarted (%s)", IntfName); 190 191 (void) signal(SIGHUP, ReConfig); 192 (void) signal(SIGINT, Exit); 193 (void) signal(SIGTERM, Exit); 194 195 /* 196 * Grab our host name and pid. 197 */ 198 if (gethostname(MyHost, MAXHOSTNAMELEN) < 0) { 199 syslog(LOG_ERR, "gethostname: %m"); 200 Exit(0); 201 } 202 MyHost[MAXHOSTNAMELEN] = '\0'; 203 204 MyPid = getpid(); 205 206 /* 207 * Write proc's pid to a file. 208 */ 209 { 210 FILE *fp; 211 212 if ((fp = fopen(PidFile, "w")) != NULL) { 213 (void) fprintf(fp, "%d\n", MyPid); 214 (void) fclose(fp); 215 } else { 216 syslog(LOG_WARNING, "fopen: failed (%s)", PidFile); 217 } 218 } 219 220 /* 221 * All boot files are relative to the boot directory, we might 222 * as well chdir() there to make life easier. 223 */ 224 if (chdir(BootDir) < 0) { 225 syslog(LOG_ERR, "chdir: %m (%s)", BootDir); 226 Exit(0); 227 } 228 229 /* 230 * Initial configuration. 231 */ 232 omask = sigblock(sigmask(SIGHUP)); /* prevent reconfig's */ 233 if (GetBootFiles() == 0) /* get list of boot files */ 234 Exit(0); 235 if (ParseConfig() == 0) /* parse config file */ 236 Exit(0); 237 238 /* 239 * Open and initialize a BPF device for the appropriate interface. 240 * If an error is encountered, a message is displayed and Exit() 241 * is called. 242 */ 243 fd = BpfOpen(); 244 245 (void) sigsetmask(omask); /* allow reconfig's */ 246 247 /* 248 * Main loop: receive a packet, determine where it came from, 249 * and if we service this host, call routine to handle request. 250 */ 251 maxfds = fd + 1; 252 FD_ZERO(&rset); 253 FD_SET(fd, &rset); 254 for (;;) { 255 struct timeval timeout; 256 fd_set r; 257 int nsel; 258 259 r = rset; 260 261 if (RmpConns == NULL) { /* timeout isnt necessary */ 262 nsel = select(maxfds, &r, (fd_set *)0, (fd_set *)0, 263 (struct timeval *)0); 264 } else { 265 timeout.tv_sec = RMP_TIMEOUT; 266 timeout.tv_usec = 0; 267 nsel = select(maxfds, &r, (fd_set *)0, (fd_set *)0, 268 &timeout); 269 } 270 271 if (nsel < 0) { 272 if (errno == EINTR) 273 continue; 274 syslog(LOG_ERR, "select: %m"); 275 Exit(0); 276 } else if (nsel == 0) { /* timeout */ 277 DoTimeout(); /* clear stale conns */ 278 continue; 279 } 280 281 if (FD_ISSET(fd, &r)) { 282 RMPCONN rconn; 283 CLIENT *client, *FindClient(); 284 int doread = 1; 285 286 while (BpfRead(&rconn, doread)) { 287 doread = 0; 288 289 if (DbgFp != NULL) /* display packet */ 290 DispPkt(&rconn,DIR_RCVD); 291 292 omask = sigblock(sigmask(SIGHUP)); 293 294 /* 295 * If we do not restrict service, set the 296 * client to NULL (ProcessPacket() handles 297 * this). Otherwise, check that we can 298 * service this host; if not, log a message 299 * and ignore the packet. 300 */ 301 if (BootAny) { 302 client = NULL; 303 } else if ((client=FindClient(&rconn))==NULL) { 304 syslog(LOG_INFO, 305 "%s: boot packet ignored", 306 EnetStr(&rconn)); 307 (void) sigsetmask(omask); 308 continue; 309 } 310 311 ProcessPacket(&rconn,client); 312 313 (void) sigsetmask(omask); 314 } 315 } 316 } 317 } 318 319 /* 320 ** DoTimeout -- Free any connections that have timed out. 321 ** 322 ** Parameters: 323 ** None. 324 ** 325 ** Returns: 326 ** Nothing. 327 ** 328 ** Side Effects: 329 ** - Timed out connections in `RmpConns' will be freed. 330 */ 331 void 332 DoTimeout() 333 { 334 register RMPCONN *rtmp; 335 struct timeval now; 336 337 (void) gettimeofday(&now, (struct timezone *)0); 338 339 /* 340 * For each active connection, if RMP_TIMEOUT seconds have passed 341 * since the last packet was sent, delete the connection. 342 */ 343 for (rtmp = RmpConns; rtmp != NULL; rtmp = rtmp->next) 344 if ((rtmp->tstamp.tv_sec + RMP_TIMEOUT) < now.tv_sec) { 345 syslog(LOG_WARNING, "%s: connection timed out (%u)", 346 EnetStr(rtmp), rtmp->rmp.r_type); 347 RemoveConn(rtmp); 348 } 349 } 350 351 /* 352 ** FindClient -- Find client associated with a packet. 353 ** 354 ** Parameters: 355 ** rconn - the new packet. 356 ** 357 ** Returns: 358 ** Pointer to client info if found, NULL otherwise. 359 ** 360 ** Side Effects: 361 ** None. 362 ** 363 ** Warnings: 364 ** - This routine must be called with SIGHUP blocked since 365 ** a reconfigure can invalidate the information returned. 366 */ 367 368 CLIENT * 369 FindClient(rconn) 370 register RMPCONN *rconn; 371 { 372 register CLIENT *ctmp; 373 374 for (ctmp = Clients; ctmp != NULL; ctmp = ctmp->next) 375 if (bcmp((char *)&rconn->rmp.hp_hdr.saddr[0], 376 (char *)&ctmp->addr[0], RMP_ADDRLEN) == 0) 377 break; 378 379 return(ctmp); 380 } 381 382 /* 383 ** Exit -- Log an error message and exit. 384 ** 385 ** Parameters: 386 ** sig - caught signal (or zero if not dying on a signal). 387 ** 388 ** Returns: 389 ** Does not return. 390 ** 391 ** Side Effects: 392 ** - This process ceases to exist. 393 */ 394 void 395 Exit(sig) 396 int sig; 397 { 398 if (sig > 0) 399 syslog(LOG_ERR, "going down on signal %d", sig); 400 else 401 syslog(LOG_ERR, "going down with fatal error"); 402 BpfClose(); 403 exit(1); 404 } 405 406 /* 407 ** ReConfig -- Get new list of boot files and reread config files. 408 ** 409 ** Parameters: 410 ** None. 411 ** 412 ** Returns: 413 ** Nothing. 414 ** 415 ** Side Effects: 416 ** - All active connections are dropped. 417 ** - List of boot-able files is changed. 418 ** - List of clients is changed. 419 ** 420 ** Warnings: 421 ** - This routine must be called with SIGHUP blocked. 422 */ 423 void 424 ReConfig(signo) 425 int signo; 426 { 427 syslog(LOG_NOTICE, "reconfiguring boot server"); 428 429 FreeConns(); 430 431 if (GetBootFiles() == 0) 432 Exit(0); 433 434 if (ParseConfig() == 0) 435 Exit(0); 436 } 437 438 /* 439 ** DebugOff -- Turn off debugging. 440 ** 441 ** Parameters: 442 ** None. 443 ** 444 ** Returns: 445 ** Nothing. 446 ** 447 ** Side Effects: 448 ** - Debug file is closed. 449 */ 450 void 451 DebugOff(signo) 452 int signo; 453 { 454 if (DbgFp != NULL) 455 (void) fclose(DbgFp); 456 457 DbgFp = NULL; 458 } 459 460 /* 461 ** DebugOn -- Turn on debugging. 462 ** 463 ** Parameters: 464 ** None. 465 ** 466 ** Returns: 467 ** Nothing. 468 ** 469 ** Side Effects: 470 ** - Debug file is opened/truncated if not already opened, 471 ** otherwise do nothing. 472 */ 473 void 474 DebugOn(signo) 475 int signo; 476 { 477 if (DbgFp == NULL) { 478 if ((DbgFp = fopen(DbgFile, "w")) == NULL) 479 syslog(LOG_ERR, "can't open debug file (%s)", DbgFile); 480 } 481 } 482