rbootd.c revision 31386
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 * from: @(#)rbootd.c 8.1 (Berkeley) 6/4/93 42 * 43 * From: Utah Hdr: rbootd.c 3.1 92/07/06 44 * Author: Jeff Forys, University of Utah CSS 45 */ 46 47#ifndef lint 48static const char copyright[] = 49"@(#) Copyright (c) 1992, 1993\n\ 50 The Regents of the University of California. All rights reserved.\n"; 51#endif /* not lint */ 52 53#ifndef lint 54#if 0 55static const char sccsid[] = "@(#)rbootd.c 8.1 (Berkeley) 6/4/93"; 56#endif 57static const char rcsid[] = 58 "$Id$"; 59#endif /* not lint */ 60 61#include <sys/param.h> 62#include <sys/time.h> 63#include <ctype.h> 64#include <err.h> 65#include <errno.h> 66#include <fcntl.h> 67#include <signal.h> 68#include <stdio.h> 69#include <stdlib.h> 70#include <string.h> 71#include <syslog.h> 72#include <unistd.h> 73#include "defs.h" 74 75static void usage __P((void)); 76 77int 78main(argc, argv) 79 int argc; 80 char *argv[]; 81{ 82 int c, fd, omask, maxfds; 83 fd_set rset; 84 85 /* 86 * Close any open file descriptors. 87 * Temporarily leave stdin & stdout open for `-d', 88 * and stderr open for any pre-syslog error messages. 89 */ 90 { 91 int i, nfds = getdtablesize(); 92 93 for (i = 0; i < nfds; i++) 94 if (i != fileno(stdin) && i != fileno(stdout) && 95 i != fileno(stderr)) 96 (void) close(i); 97 } 98 99 /* 100 * Parse any arguments. 101 */ 102 while ((c = getopt(argc, argv, "adi:")) != -1) 103 switch(c) { 104 case 'a': 105 BootAny++; 106 break; 107 case 'd': 108 DebugFlg++; 109 break; 110 case 'i': 111 IntfName = optarg; 112 break; 113 default: 114 usage(); 115 } 116 for (; optind < argc; optind++) { 117 if (ConfigFile == NULL) 118 ConfigFile = argv[optind]; 119 else { 120 warnx("too many config files (`%s' ignored)", 121 argv[optind]); 122 } 123 } 124 125 if (ConfigFile == NULL) /* use default config file */ 126 ConfigFile = DfltConfig; 127 128 if (DebugFlg) { 129 DbgFp = stdout; /* output to stdout */ 130 131 (void) signal(SIGUSR1, SIG_IGN); /* dont muck w/DbgFp */ 132 (void) signal(SIGUSR2, SIG_IGN); 133 (void) fclose(stderr); /* finished with it */ 134 } else { 135 if (daemon(0, 0)) 136 err(1, "can't detach from terminal"); 137 138 (void) signal(SIGUSR1, DebugOn); 139 (void) signal(SIGUSR2, DebugOff); 140 } 141 142 openlog("rbootd", LOG_PID, LOG_DAEMON); 143 144 /* 145 * If no interface was specified, get one now. 146 * 147 * This is convoluted because we want to get the default interface 148 * name for the syslog("restarted") message. If BpfGetIntfName() 149 * runs into an error, it will return a syslog-able error message 150 * (in `errmsg') which will be displayed here. 151 */ 152 if (IntfName == NULL) { 153 char *errmsg; 154 155 if ((IntfName = BpfGetIntfName(&errmsg)) == NULL) { 156 syslog(LOG_NOTICE, "restarted (??)"); 157 syslog(LOG_ERR, errmsg); 158 Exit(0); 159 } 160 } 161 162 syslog(LOG_NOTICE, "restarted (%s)", IntfName); 163 164 (void) signal(SIGHUP, ReConfig); 165 (void) signal(SIGINT, Exit); 166 (void) signal(SIGTERM, Exit); 167 168 /* 169 * Grab our host name and pid. 170 */ 171 if (gethostname(MyHost, MAXHOSTNAMELEN) < 0) { 172 syslog(LOG_ERR, "gethostname: %m"); 173 Exit(0); 174 } 175 MyHost[MAXHOSTNAMELEN] = '\0'; 176 177 MyPid = getpid(); 178 179 /* 180 * Write proc's pid to a file. 181 */ 182 { 183 FILE *fp; 184 185 if ((fp = fopen(PidFile, "w")) != NULL) { 186 (void) fprintf(fp, "%d\n", (int) MyPid); 187 (void) fclose(fp); 188 } else { 189 syslog(LOG_WARNING, "fopen: failed (%s)", PidFile); 190 } 191 } 192 193 /* 194 * All boot files are relative to the boot directory, we might 195 * as well chdir() there to make life easier. 196 */ 197 if (chdir(BootDir) < 0) { 198 syslog(LOG_ERR, "chdir: %m (%s)", BootDir); 199 Exit(0); 200 } 201 202 /* 203 * Initial configuration. 204 */ 205 omask = sigblock(sigmask(SIGHUP)); /* prevent reconfig's */ 206 if (GetBootFiles() == 0) /* get list of boot files */ 207 Exit(0); 208 if (ParseConfig() == 0) /* parse config file */ 209 Exit(0); 210 211 /* 212 * Open and initialize a BPF device for the appropriate interface. 213 * If an error is encountered, a message is displayed and Exit() 214 * is called. 215 */ 216 fd = BpfOpen(); 217 218 (void) sigsetmask(omask); /* allow reconfig's */ 219 220 /* 221 * Main loop: receive a packet, determine where it came from, 222 * and if we service this host, call routine to handle request. 223 */ 224 maxfds = fd + 1; 225 FD_ZERO(&rset); 226 FD_SET(fd, &rset); 227 for (;;) { 228 struct timeval timeout; 229 fd_set r; 230 int nsel; 231 232 r = rset; 233 234 if (RmpConns == NULL) { /* timeout isnt necessary */ 235 nsel = select(maxfds, &r, NULL, NULL, NULL); 236 } else { 237 timeout.tv_sec = RMP_TIMEOUT; 238 timeout.tv_usec = 0; 239 nsel = select(maxfds, &r, NULL, NULL, &timeout); 240 } 241 242 if (nsel < 0) { 243 if (errno == EINTR) 244 continue; 245 syslog(LOG_ERR, "select: %m"); 246 Exit(0); 247 } else if (nsel == 0) { /* timeout */ 248 DoTimeout(); /* clear stale conns */ 249 continue; 250 } 251 252 if (FD_ISSET(fd, &r)) { 253 RMPCONN rconn; 254 CLIENT *client, *FindClient(); 255 int doread = 1; 256 257 while (BpfRead(&rconn, doread)) { 258 doread = 0; 259 260 if (DbgFp != NULL) /* display packet */ 261 DispPkt(&rconn,DIR_RCVD); 262 263 omask = sigblock(sigmask(SIGHUP)); 264 265 /* 266 * If we do not restrict service, set the 267 * client to NULL (ProcessPacket() handles 268 * this). Otherwise, check that we can 269 * service this host; if not, log a message 270 * and ignore the packet. 271 */ 272 if (BootAny) { 273 client = NULL; 274 } else if ((client=FindClient(&rconn))==NULL) { 275 syslog(LOG_INFO, 276 "%s: boot packet ignored", 277 EnetStr(&rconn)); 278 (void) sigsetmask(omask); 279 continue; 280 } 281 282 ProcessPacket(&rconn,client); 283 284 (void) sigsetmask(omask); 285 } 286 } 287 } 288} 289 290static void 291usage() 292{ 293 fprintf(stderr, "usage: rbootd [-ad] [-i interface] [config_file]\n"); 294 exit (1); 295} 296 297/* 298** DoTimeout -- Free any connections that have timed out. 299** 300** Parameters: 301** None. 302** 303** Returns: 304** Nothing. 305** 306** Side Effects: 307** - Timed out connections in `RmpConns' will be freed. 308*/ 309void 310DoTimeout() 311{ 312 RMPCONN *rtmp; 313 struct timeval now; 314 315 (void) gettimeofday(&now, (struct timezone *)0); 316 317 /* 318 * For each active connection, if RMP_TIMEOUT seconds have passed 319 * since the last packet was sent, delete the connection. 320 */ 321 for (rtmp = RmpConns; rtmp != NULL; rtmp = rtmp->next) 322 if ((rtmp->tstamp.tv_sec + RMP_TIMEOUT) < now.tv_sec) { 323 syslog(LOG_WARNING, "%s: connection timed out (%u)", 324 EnetStr(rtmp), rtmp->rmp.r_type); 325 RemoveConn(rtmp); 326 } 327} 328 329/* 330** FindClient -- Find client associated with a packet. 331** 332** Parameters: 333** rconn - the new packet. 334** 335** Returns: 336** Pointer to client info if found, NULL otherwise. 337** 338** Side Effects: 339** None. 340** 341** Warnings: 342** - This routine must be called with SIGHUP blocked since 343** a reconfigure can invalidate the information returned. 344*/ 345 346CLIENT * 347FindClient(rconn) 348 RMPCONN *rconn; 349{ 350 CLIENT *ctmp; 351 352 for (ctmp = Clients; ctmp != NULL; ctmp = ctmp->next) 353 if (bcmp((char *)&rconn->rmp.hp_hdr.saddr[0], 354 (char *)&ctmp->addr[0], RMP_ADDRLEN) == 0) 355 break; 356 357 return(ctmp); 358} 359 360/* 361** Exit -- Log an error message and exit. 362** 363** Parameters: 364** sig - caught signal (or zero if not dying on a signal). 365** 366** Returns: 367** Does not return. 368** 369** Side Effects: 370** - This process ceases to exist. 371*/ 372void 373Exit(sig) 374 int sig; 375{ 376 if (sig > 0) 377 syslog(LOG_ERR, "going down on signal %d", sig); 378 else 379 syslog(LOG_ERR, "going down with fatal error"); 380 BpfClose(); 381 exit(1); 382} 383 384/* 385** ReConfig -- Get new list of boot files and reread config files. 386** 387** Parameters: 388** None. 389** 390** Returns: 391** Nothing. 392** 393** Side Effects: 394** - All active connections are dropped. 395** - List of boot-able files is changed. 396** - List of clients is changed. 397** 398** Warnings: 399** - This routine must be called with SIGHUP blocked. 400*/ 401void 402ReConfig(signo) 403 int signo; 404{ 405 syslog(LOG_NOTICE, "reconfiguring boot server"); 406 407 FreeConns(); 408 409 if (GetBootFiles() == 0) 410 Exit(0); 411 412 if (ParseConfig() == 0) 413 Exit(0); 414} 415 416/* 417** DebugOff -- Turn off debugging. 418** 419** Parameters: 420** None. 421** 422** Returns: 423** Nothing. 424** 425** Side Effects: 426** - Debug file is closed. 427*/ 428void 429DebugOff(signo) 430 int signo; 431{ 432 if (DbgFp != NULL) 433 (void) fclose(DbgFp); 434 435 DbgFp = NULL; 436} 437 438/* 439** DebugOn -- Turn on debugging. 440** 441** Parameters: 442** None. 443** 444** Returns: 445** Nothing. 446** 447** Side Effects: 448** - Debug file is opened/truncated if not already opened, 449** otherwise do nothing. 450*/ 451void 452DebugOn(signo) 453 int signo; 454{ 455 if (DbgFp == NULL) { 456 if ((DbgFp = fopen(DbgFile, "w")) == NULL) 457 syslog(LOG_ERR, "can't open debug file (%s)", DbgFile); 458 } 459} 460