rbootd.c revision 24349
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. All advertising materials mentioning features or use of this software 22 * must display the following acknowledgement: 23 * This product includes software developed by the University of 24 * California, Berkeley and its contributors. 25 * 4. Neither the name of the University nor the names of its contributors 26 * may be used to endorse or promote products derived from this software 27 * without specific prior written permission. 28 * 29 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 30 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 31 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 32 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 33 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 34 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 35 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 36 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 37 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 38 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 39 * SUCH DAMAGE. 40 * 41 * @(#)rbootd.c 8.2 (Berkeley) 2/22/94 42 * $Id: rbootd.c,v 1.5 1997/02/22 14:21:58 peter Exp $ 43 * 44 * Utah $Hdr: rbootd.c 3.1 92/07/06$ 45 * Author: Jeff Forys, University of Utah CSS 46 */ 47 48#ifndef lint 49static char copyright[] = 50"@(#) Copyright (c) 1992, 1993\n\ 51 The Regents of the University of California. All rights reserved.\n"; 52#endif /* not lint */ 53 54#ifndef lint 55static char sccsid[] = "@(#)rbootd.c 8.2 (Berkeley) 2/22/94"; 56#endif /* not lint */ 57 58#include <sys/param.h> 59#include <sys/ioctl.h> 60#include <sys/time.h> 61 62#include <ctype.h> 63#include <errno.h> 64#include <fcntl.h> 65#include <signal.h> 66#include <stdio.h> 67#include <stdlib.h> 68#include <string.h> 69#include <syslog.h> 70#include <unistd.h> 71#include "defs.h" 72 73 74/* fd mask macros (backward compatibility with 4.2BSD) */ 75#ifndef FD_SET 76#ifdef notdef 77typedef struct fd_set { /* this should already be in 4.2 */ 78 int fds_bits[1]; 79} fd_set; 80#endif 81#define FD_ZERO(p) ((p)->fds_bits[0] = 0) 82#define FD_SET(n, p) ((p)->fds_bits[0] |= (1 << (n))) 83#define FD_CLR(n, p) ((p)->fds_bits[0] &= ~(1 << (n))) 84#define FD_ISSET(n, p) ((p)->fds_bits[0] & (1 << (n))) 85#endif 86 87int 88main(argc, argv) 89 int argc; 90 char *argv[]; 91{ 92 int c, fd, omask, maxfds; 93 fd_set rset; 94 95 /* 96 * Find what name we are running under. 97 */ 98 ProgName = (ProgName = rindex(argv[0],'/')) ? ++ProgName : *argv; 99 100 /* 101 * Close any open file descriptors. 102 * Temporarily leave stdin & stdout open for `-d', 103 * and stderr open for any pre-syslog error messages. 104 */ 105 { 106 int i, nfds = getdtablesize(); 107 108 for (i = 0; i < nfds; i++) 109 if (i != fileno(stdin) && i != fileno(stdout) && 110 i != fileno(stderr)) 111 (void) close(i); 112 } 113 114 /* 115 * Parse any arguments. 116 */ 117 while ((c = getopt(argc, argv, "adi:")) != -1) 118 switch(c) { 119 case 'a': 120 BootAny++; 121 break; 122 case 'd': 123 DebugFlg++; 124 break; 125 case 'i': 126 IntfName = optarg; 127 break; 128 } 129 for (; optind < argc; optind++) { 130 if (ConfigFile == NULL) 131 ConfigFile = argv[optind]; 132 else { 133 fprintf(stderr, 134 "%s: too many config files (`%s' ignored)\n", 135 ProgName, argv[optind]); 136 } 137 } 138 139 if (ConfigFile == NULL) /* use default config file */ 140 ConfigFile = DfltConfig; 141 142 if (DebugFlg) { 143 DbgFp = stdout; /* output to stdout */ 144 145 (void) signal(SIGUSR1, SIG_IGN); /* dont muck w/DbgFp */ 146 (void) signal(SIGUSR2, SIG_IGN); 147 } else { 148 (void) fclose(stdin); /* dont need these */ 149 (void) fclose(stdout); 150 151 /* 152 * Fork off a child to do the work & exit. 153 */ 154 switch(fork()) { 155 case -1: /* fork failed */ 156 fprintf(stderr, "%s: ", ProgName); 157 perror("fork"); 158 Exit(0); 159 case 0: /* this is the CHILD */ 160 break; 161 default: /* this is the PARENT */ 162 _exit(0); 163 } 164 165 /* 166 * Try to disassociate from the current tty. 167 */ 168 { 169 char *devtty = "/dev/tty"; 170 int i; 171 172 if ((i = open(devtty, O_RDWR)) < 0) { 173 /* probably already disassociated */ 174 if (setpgrp(0, 0) < 0) { 175 fprintf(stderr, "%s: ", ProgName); 176 perror("setpgrp"); 177 } 178 } else { 179 if (ioctl(i, (u_long)TIOCNOTTY, (char *)0) < 0){ 180 fprintf(stderr, "%s: ", ProgName); 181 perror("ioctl"); 182 } 183 (void) close(i); 184 } 185 } 186 187 (void) signal(SIGUSR1, DebugOn); 188 (void) signal(SIGUSR2, DebugOff); 189 } 190 191 (void) fclose(stderr); /* finished with it */ 192 193#ifdef SYSLOG4_2 194 openlog(ProgName, LOG_PID); 195#else 196 openlog(ProgName, LOG_PID, LOG_DAEMON); 197#endif 198 199 /* 200 * If no interface was specified, get one now. 201 * 202 * This is convoluted because we want to get the default interface 203 * name for the syslog("restarted") message. If BpfGetIntfName() 204 * runs into an error, it will return a syslog-able error message 205 * (in `errmsg') which will be displayed here. 206 */ 207 if (IntfName == NULL) { 208 char *errmsg; 209 210 if ((IntfName = BpfGetIntfName(&errmsg)) == NULL) { 211 syslog(LOG_NOTICE, "restarted (??)"); 212 syslog(LOG_ERR, errmsg); 213 Exit(0); 214 } 215 } 216 217 syslog(LOG_NOTICE, "restarted (%s)", IntfName); 218 219 (void) signal(SIGHUP, ReConfig); 220 (void) signal(SIGINT, Exit); 221 (void) signal(SIGTERM, Exit); 222 223 /* 224 * Grab our host name and pid. 225 */ 226 if (gethostname(MyHost, MAXHOSTNAMELEN) < 0) { 227 syslog(LOG_ERR, "gethostname: %m"); 228 Exit(0); 229 } 230 MyHost[MAXHOSTNAMELEN] = '\0'; 231 232 MyPid = getpid(); 233 234 /* 235 * Write proc's pid to a file. 236 */ 237 { 238 FILE *fp; 239 240 if ((fp = fopen(PidFile, "w")) != NULL) { 241 (void) fprintf(fp, "%d\n", MyPid); 242 (void) fclose(fp); 243 } else { 244 syslog(LOG_WARNING, "fopen: failed (%s)", PidFile); 245 } 246 } 247 248 /* 249 * All boot files are relative to the boot directory, we might 250 * as well chdir() there to make life easier. 251 */ 252 if (chdir(BootDir) < 0) { 253 syslog(LOG_ERR, "chdir: %m (%s)", BootDir); 254 Exit(0); 255 } 256 257 /* 258 * Initial configuration. 259 */ 260 omask = sigblock(sigmask(SIGHUP)); /* prevent reconfig's */ 261 if (GetBootFiles() == 0) /* get list of boot files */ 262 Exit(0); 263 if (ParseConfig() == 0) /* parse config file */ 264 Exit(0); 265 266 /* 267 * Open and initialize a BPF device for the appropriate interface. 268 * If an error is encountered, a message is displayed and Exit() 269 * is called. 270 */ 271 fd = BpfOpen(); 272 273 (void) sigsetmask(omask); /* allow reconfig's */ 274 275 /* 276 * Main loop: receive a packet, determine where it came from, 277 * and if we service this host, call routine to handle request. 278 */ 279 maxfds = fd + 1; 280 FD_ZERO(&rset); 281 FD_SET(fd, &rset); 282 for (;;) { 283 struct timeval timeout; 284 fd_set r; 285 int nsel; 286 287 r = rset; 288 289 if (RmpConns == NULL) { /* timeout isnt necessary */ 290 nsel = select(maxfds, &r, (fd_set *)0, (fd_set *)0, 291 (struct timeval *)0); 292 } else { 293 timeout.tv_sec = RMP_TIMEOUT; 294 timeout.tv_usec = 0; 295 nsel = select(maxfds, &r, (fd_set *)0, (fd_set *)0, 296 &timeout); 297 } 298 299 if (nsel < 0) { 300 if (errno == EINTR) 301 continue; 302 syslog(LOG_ERR, "select: %m"); 303 Exit(0); 304 } else if (nsel == 0) { /* timeout */ 305 DoTimeout(); /* clear stale conns */ 306 continue; 307 } 308 309 if (FD_ISSET(fd, &r)) { 310 RMPCONN rconn; 311 CLIENT *client, *FindClient(); 312 int doread = 1; 313 314 while (BpfRead(&rconn, doread)) { 315 doread = 0; 316 317 if (DbgFp != NULL) /* display packet */ 318 DispPkt(&rconn,DIR_RCVD); 319 320 omask = sigblock(sigmask(SIGHUP)); 321 322 /* 323 * If we do not restrict service, set the 324 * client to NULL (ProcessPacket() handles 325 * this). Otherwise, check that we can 326 * service this host; if not, log a message 327 * and ignore the packet. 328 */ 329 if (BootAny) { 330 client = NULL; 331 } else if ((client=FindClient(&rconn))==NULL) { 332 syslog(LOG_INFO, 333 "%s: boot packet ignored", 334 EnetStr(&rconn)); 335 (void) sigsetmask(omask); 336 continue; 337 } 338 339 ProcessPacket(&rconn,client); 340 341 (void) sigsetmask(omask); 342 } 343 } 344 } 345} 346 347/* 348** DoTimeout -- Free any connections that have timed out. 349** 350** Parameters: 351** None. 352** 353** Returns: 354** Nothing. 355** 356** Side Effects: 357** - Timed out connections in `RmpConns' will be freed. 358*/ 359void 360DoTimeout() 361{ 362 register RMPCONN *rtmp; 363 struct timeval now; 364 365 (void) gettimeofday(&now, (struct timezone *)0); 366 367 /* 368 * For each active connection, if RMP_TIMEOUT seconds have passed 369 * since the last packet was sent, delete the connection. 370 */ 371 for (rtmp = RmpConns; rtmp != NULL; rtmp = rtmp->next) 372 if ((rtmp->tstamp.tv_sec + RMP_TIMEOUT) < now.tv_sec) { 373 syslog(LOG_WARNING, "%s: connection timed out (%u)", 374 EnetStr(rtmp), rtmp->rmp.r_type); 375 RemoveConn(rtmp); 376 } 377} 378 379/* 380** FindClient -- Find client associated with a packet. 381** 382** Parameters: 383** rconn - the new packet. 384** 385** Returns: 386** Pointer to client info if found, NULL otherwise. 387** 388** Side Effects: 389** None. 390** 391** Warnings: 392** - This routine must be called with SIGHUP blocked since 393** a reconfigure can invalidate the information returned. 394*/ 395 396CLIENT * 397FindClient(rconn) 398 register RMPCONN *rconn; 399{ 400 register CLIENT *ctmp; 401 402 for (ctmp = Clients; ctmp != NULL; ctmp = ctmp->next) 403 if (bcmp((char *)&rconn->rmp.hp_hdr.saddr[0], 404 (char *)&ctmp->addr[0], RMP_ADDRLEN) == 0) 405 break; 406 407 return(ctmp); 408} 409 410/* 411** Exit -- Log an error message and exit. 412** 413** Parameters: 414** sig - caught signal (or zero if not dying on a signal). 415** 416** Returns: 417** Does not return. 418** 419** Side Effects: 420** - This process ceases to exist. 421*/ 422void 423Exit(sig) 424 int sig; 425{ 426 if (sig > 0) 427 syslog(LOG_ERR, "going down on signal %d", sig); 428 else 429 syslog(LOG_ERR, "going down with fatal error"); 430 BpfClose(); 431 exit(1); 432} 433 434/* 435** ReConfig -- Get new list of boot files and reread config files. 436** 437** Parameters: 438** None. 439** 440** Returns: 441** Nothing. 442** 443** Side Effects: 444** - All active connections are dropped. 445** - List of boot-able files is changed. 446** - List of clients is changed. 447** 448** Warnings: 449** - This routine must be called with SIGHUP blocked. 450*/ 451void 452ReConfig(signo) 453 int signo; 454{ 455 syslog(LOG_NOTICE, "reconfiguring boot server"); 456 457 FreeConns(); 458 459 if (GetBootFiles() == 0) 460 Exit(0); 461 462 if (ParseConfig() == 0) 463 Exit(0); 464} 465 466/* 467** DebugOff -- Turn off debugging. 468** 469** Parameters: 470** None. 471** 472** Returns: 473** Nothing. 474** 475** Side Effects: 476** - Debug file is closed. 477*/ 478void 479DebugOff(signo) 480 int signo; 481{ 482 if (DbgFp != NULL) 483 (void) fclose(DbgFp); 484 485 DbgFp = NULL; 486} 487 488/* 489** DebugOn -- Turn on debugging. 490** 491** Parameters: 492** None. 493** 494** Returns: 495** Nothing. 496** 497** Side Effects: 498** - Debug file is opened/truncated if not already opened, 499** otherwise do nothing. 500*/ 501void 502DebugOn(signo) 503 int signo; 504{ 505 if (DbgFp == NULL) { 506 if ((DbgFp = fopen(DbgFile, "w")) == NULL) 507 syslog(LOG_ERR, "can't open debug file (%s)", DbgFile); 508 } 509} 510