rbootd.tproj/rbootd.c

   1 /*
   2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * "Portions Copyright (c) 1999 Apple Computer, Inc.  All Rights
   7  * Reserved.  This file contains Original Code and/or Modifications of
   8  * Original Code as defined in and that are subject to the Apple Public
   9  * Source License Version 1.0 (the 'License').  You may not use this file
  10  * except in compliance with the License.  Please obtain a copy of the
  11  * License at http://www.apple.com/publicsource and read it before using
  12  * this file.
  13  *
  14  * The Original Code and all software distributed under the License are
  15  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  16  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  17  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  19  * License for the specific language governing rights and limitations
  20  * under the License."
  21  *
  22  * @APPLE_LICENSE_HEADER_END@
  23  */
  24 /*
  25  * Copyright (c) 1988, 1992 The University of Utah and the Center
  26  *      for Software Science (CSS).
  27  * Copyright (c) 1992, 1993
  28  *      The Regents of the University of California.  All rights reserved.
  29  *
  30  * This code is derived from software contributed to Berkeley by
  31  * the Center for Software Science of the University of Utah Computer
  32  * Science Department.  CSS requests users of this software to return
  33  * to css-dist@cs.utah.edu any improvements that they make and grant
  34  * CSS redistribution rights.
  35  *
  36  * Redistribution and use in source and binary forms, with or without
  37  * modification, are permitted provided that the following conditions
  38  * are met:
  39  * 1. Redistributions of source code must retain the above copyright
  40  *    notice, this list of conditions and the following disclaimer.
  41  * 2. Redistributions in binary form must reproduce the above copyright
  42  *    notice, this list of conditions and the following disclaimer in the
  43  *    documentation and/or other materials provided with the distribution.
  44  * 3. All advertising materials mentioning features or use of this software
  45  *    must display the following acknowledgement:
  46  *      This product includes software developed by the University of
  47  *      California, Berkeley and its contributors.
  48  * 4. Neither the name of the University nor the names of its contributors
  49  *    may be used to endorse or promote products derived from this software
  50  *    without specific prior written permission.
  51  *
  52  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  53  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  54  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  55  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  56  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  57  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  58  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  59  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  60  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  61  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  62  * SUCH DAMAGE.
  63  *
  64  *      @(#)rbootd.c    8.2 (Berkeley) 2/22/94
  65  *
  66  * Utah $Hdr: rbootd.c 3.1 92/07/06$
  67  * Author: Jeff Forys, University of Utah CSS
  68  */
  69
  70 #ifndef lint
  71 static char copyright[] =
  72 "@(#) Copyright (c) 1992, 1993\n\
  73         The Regents of the University of California.  All rights reserved.\n";
  74 #endif /* not lint */
  75
  76 #ifndef lint
  77 static char sccsid[] = "@(#)rbootd.c    8.2 (Berkeley) 2/22/94";
  78 #endif /* not lint */
  79
  80 #include <sys/param.h>
  81 #include <sys/ioctl.h>
  82 #include <sys/time.h>
  83
  84 #include <ctype.h>
  85 #include <errno.h>
  86 #include <fcntl.h>
  87 #include <signal.h>
  88 #include <stdio.h>
  89 #include <stdlib.h>
  90 #include <string.h>
  91 #include <syslog.h>
  92 #include <unistd.h>
  93 #include "defs.h"
  94
  95
  96 /* fd mask macros (backward compatibility with 4.2BSD) */
  97 #ifndef FD_SET
  98 #ifdef  notdef
  99 typedef struct fd_set {         /* this should already be in 4.2 */
 100         int fds_bits[1];
 101 } fd_set;
 102 #endif
 103 #define FD_ZERO(p)      ((p)->fds_bits[0] = 0)
 104 #define FD_SET(n, p)    ((p)->fds_bits[0] |= (1 << (n)))
 105 #define FD_CLR(n, p)    ((p)->fds_bits[0] &= ~(1 << (n)))
 106 #define FD_ISSET(n, p)  ((p)->fds_bits[0] & (1 << (n)))
 107 #endif
 108
 109 int
 110 main(argc, argv)
 111         int argc;
 112         char *argv[];
 113 {
 114         int c, fd, omask, maxfds;
 115         fd_set rset;
 116
 117         /*
 118          *  Find what name we are running under.
 119          */
 120         ProgName = (ProgName = rindex(argv[0],'/')) ? ++ProgName : *argv;
 121
 122         /*
 123          *  Close any open file descriptors.
 124          *  Temporarily leave stdin & stdout open for `-d',
 125          *  and stderr open for any pre-syslog error messages.
 126          */
 127         {
 128                 int i, nfds = getdtablesize();
 129
 130                 for (i = 0; i < nfds; i++)
 131                         if (i != fileno(stdin) && i != fileno(stdout) &&
 132                             i != fileno(stderr))
 133                                 (void) close(i);
 134         }
 135
 136         /*
 137          *  Parse any arguments.
 138          */
 139         while ((c = getopt(argc, argv, "adi:")) != EOF)
 140                 switch(c) {
 141                     case 'a':
 142                         BootAny++;
 143                         break;
 144                     case 'd':
 145                         DebugFlg++;
 146                         break;
 147                     case 'i':
 148                         IntfName = optarg;
 149                         break;
 150                 }
 151         for (; optind < argc; optind++) {
 152                 if (ConfigFile == NULL)
 153                         ConfigFile = argv[optind];
 154                 else {
 155                         fprintf(stderr,
 156                                 "%s: too many config files (`%s' ignored)\n",
 157                                 ProgName, argv[optind]);
 158                 }
 159         }
 160
 161         if (ConfigFile == NULL)                 /* use default config file */
 162                 ConfigFile = DfltConfig;
 163
 164         if (DebugFlg) {
 165                 DbgFp = stdout;                         /* output to stdout */
 166
 167                 (void) signal(SIGUSR1, SIG_IGN);        /* dont muck w/DbgFp */
 168                 (void) signal(SIGUSR2, SIG_IGN);
 169         } else {
 170                 (void) fclose(stdin);                   /* dont need these */
 171                 (void) fclose(stdout);
 172
 173                 /*
 174                  *  Fork off a child to do the work & exit.
 175                  */
 176                 switch(fork()) {
 177                         case -1:        /* fork failed */
 178                                 fprintf(stderr, "%s: ", ProgName);
 179                                 perror("fork");
 180                                 Exit(0);
 181                         case 0:         /* this is the CHILD */
 182                                 break;
 183                         default:        /* this is the PARENT */
 184                                 _exit(0);
 185                 }
 186
 187                 /*
 188                  *  Try to disassociate from the current tty.
 189                  */
 190                 {
 191                         char *devtty = "/dev/tty";
 192                         int i;
 193
 194                         if ((i = open(devtty, O_RDWR)) < 0) {
 195                                 /* probably already disassociated */
 196                                 if (setpgrp(0, 0) < 0) {
 197                                         fprintf(stderr, "%s: ", ProgName);
 198                                         perror("setpgrp");
 199                                 }
 200                         } else {
 201                                 if (ioctl(i, (u_long)TIOCNOTTY, (char *)0) < 0){
 202                                         fprintf(stderr, "%s: ", ProgName);
 203                                         perror("ioctl");
 204                                 }
 205                                 (void) close(i);
 206                         }
 207                 }
 208
 209                 (void) signal(SIGUSR1, DebugOn);
 210                 (void) signal(SIGUSR2, DebugOff);
 211         }
 212
 213         (void) fclose(stderr);          /* finished with it */
 214
 215 #ifdef SYSLOG4_2
 216         openlog(ProgName, LOG_PID);
 217 #else
 218         openlog(ProgName, LOG_PID, LOG_DAEMON);
 219 #endif
 220
 221         /*
 222          *  If no interface was specified, get one now.
 223          *
 224          *  This is convoluted because we want to get the default interface
 225          *  name for the syslog("restarted") message.  If BpfGetIntfName()
 226          *  runs into an error, it will return a syslog-able error message
 227          *  (in `errmsg') which will be displayed here.
 228          */
 229         if (IntfName == NULL) {
 230                 char *errmsg;
 231
 232                 if ((IntfName = BpfGetIntfName(&errmsg)) == NULL) {
 233                         syslog(LOG_NOTICE, "restarted (??)");
 234                         syslog(LOG_ERR, errmsg);
 235                         Exit(0);
 236                 }
 237         }
 238
 239         syslog(LOG_NOTICE, "restarted (%s)", IntfName);
 240
 241         (void) signal(SIGHUP, ReConfig);
 242         (void) signal(SIGINT, Exit);
 243         (void) signal(SIGTERM, Exit);
 244
 245         /*
 246          *  Grab our host name and pid.
 247          */
 248         if (gethostname(MyHost, MAXHOSTNAMELEN) < 0) {
 249                 syslog(LOG_ERR, "gethostname: %m");
 250                 Exit(0);
 251         }
 252         MyHost[MAXHOSTNAMELEN] = '\0';
 253
 254         MyPid = getpid();
 255
 256         /*
 257          *  Write proc's pid to a file.
 258          */
 259         {
 260                 FILE *fp;
 261
 262                 if ((fp = fopen(PidFile, "w")) != NULL) {
 263                         (void) fprintf(fp, "%d\n", MyPid);
 264                         (void) fclose(fp);
 265                 } else {
 266                         syslog(LOG_WARNING, "fopen: failed (%s)", PidFile);
 267                 }
 268         }
 269
 270         /*
 271          *  All boot files are relative to the boot directory, we might
 272          *  as well chdir() there to make life easier.
 273          */
 274         if (chdir(BootDir) < 0) {
 275                 syslog(LOG_ERR, "chdir: %m (%s)", BootDir);
 276                 Exit(0);
 277         }
 278
 279         /*
 280          *  Initial configuration.
 281          */
 282         omask = sigblock(sigmask(SIGHUP));      /* prevent reconfig's */
 283         if (GetBootFiles() == 0)                /* get list of boot files */
 284                 Exit(0);
 285         if (ParseConfig() == 0)                 /* parse config file */
 286                 Exit(0);
 287
 288         /*
 289          *  Open and initialize a BPF device for the appropriate interface.
 290          *  If an error is encountered, a message is displayed and Exit()
 291          *  is called.
 292          */
 293         fd = BpfOpen();
 294
 295         (void) sigsetmask(omask);               /* allow reconfig's */
 296
 297         /*
 298          *  Main loop: receive a packet, determine where it came from,
 299          *  and if we service this host, call routine to handle request.
 300          */
 301         maxfds = fd + 1;
 302         FD_ZERO(&rset);
 303         FD_SET(fd, &rset);
 304         for (;;) {
 305                 struct timeval timeout;
 306                 fd_set r;
 307                 int nsel;
 308
 309                 r = rset;
 310
 311                 if (RmpConns == NULL) {         /* timeout isnt necessary */
 312                         nsel = select(maxfds, &r, (fd_set *)0, (fd_set *)0,
 313                                       (struct timeval *)0);
 314                 } else {
 315                         timeout.tv_sec = RMP_TIMEOUT;
 316                         timeout.tv_usec = 0;
 317                         nsel = select(maxfds, &r, (fd_set *)0, (fd_set *)0,
 318                                       &timeout);
 319                 }
 320
 321                 if (nsel < 0) {
 322                         if (errno == EINTR)
 323                                 continue;
 324                         syslog(LOG_ERR, "select: %m");
 325                         Exit(0);
 326                 } else if (nsel == 0) {         /* timeout */
 327                         DoTimeout();                    /* clear stale conns */
 328                         continue;
 329                 }
 330
 331                 if (FD_ISSET(fd, &r)) {
 332                         RMPCONN rconn;
 333                         CLIENT *client, *FindClient();
 334                         int doread = 1;
 335
 336                         while (BpfRead(&rconn, doread)) {
 337                                 doread = 0;
 338
 339                                 if (DbgFp != NULL)      /* display packet */
 340                                         DispPkt(&rconn,DIR_RCVD);
 341
 342                                 omask = sigblock(sigmask(SIGHUP));
 343
 344                                 /*
 345                                  *  If we do not restrict service, set the
 346                                  *  client to NULL (ProcessPacket() handles
 347                                  *  this).  Otherwise, check that we can
 348                                  *  service this host; if not, log a message
 349                                  *  and ignore the packet.
 350                                  */
 351                                 if (BootAny) {
 352                                         client = NULL;
 353                                 } else if ((client=FindClient(&rconn))==NULL) {
 354                                         syslog(LOG_INFO,
 355                                                "%s: boot packet ignored",
 356                                                EnetStr(&rconn));
 357                                         (void) sigsetmask(omask);
 358                                         continue;
 359                                 }
 360
 361                                 ProcessPacket(&rconn,client);
 362
 363                                 (void) sigsetmask(omask);
 364                         }
 365                 }
 366         }
 367 }
 368
 369 /*
 370 **  DoTimeout -- Free any connections that have timed out.
 371 **
 372 **      Parameters:
 373 **              None.
 374 **
 375 **      Returns:
 376 **              Nothing.
 377 **
 378 **      Side Effects:
 379 **              - Timed out connections in `RmpConns' will be freed.
 380 */
 381 void
 382 DoTimeout()
 383 {
 384         register RMPCONN *rtmp;
 385         struct timeval now;
 386
 387         (void) gettimeofday(&now, (struct timezone *)0);
 388
 389         /*
 390          *  For each active connection, if RMP_TIMEOUT seconds have passed
 391          *  since the last packet was sent, delete the connection.
 392          */
 393         for (rtmp = RmpConns; rtmp != NULL; rtmp = rtmp->next)
 394                 if ((rtmp->tstamp.tv_sec + RMP_TIMEOUT) < now.tv_sec) {
 395                         syslog(LOG_WARNING, "%s: connection timed out (%u)",
 396                                EnetStr(rtmp), rtmp->rmp.r_type);
 397                         RemoveConn(rtmp);
 398                 }
 399 }
 400
 401 /*
 402 **  FindClient -- Find client associated with a packet.
 403 **
 404 **      Parameters:
 405 **              rconn - the new packet.
 406 **
 407 **      Returns:
 408 **              Pointer to client info if found, NULL otherwise.
 409 **
 410 **      Side Effects:
 411 **              None.
 412 **
 413 **      Warnings:
 414 **              - This routine must be called with SIGHUP blocked since
 415 **                a reconfigure can invalidate the information returned.
 416 */
 417
 418 CLIENT *
 419 FindClient(rconn)
 420         register RMPCONN *rconn;
 421 {
 422         register CLIENT *ctmp;
 423
 424         for (ctmp = Clients; ctmp != NULL; ctmp = ctmp->next)
 425                 if (bcmp((char *)&rconn->rmp.hp_hdr.saddr[0],
 426                          (char *)&ctmp->addr[0], RMP_ADDRLEN) == 0)
 427                         break;
 428
 429         return(ctmp);
 430 }
 431
 432 /*
 433 **  Exit -- Log an error message and exit.
 434 **
 435 **      Parameters:
 436 **              sig - caught signal (or zero if not dying on a signal).
 437 **
 438 **      Returns:
 439 **              Does not return.
 440 **
 441 **      Side Effects:
 442 **              - This process ceases to exist.
 443 */
 444 void
 445 Exit(sig)
 446         int sig;
 447 {
 448         if (sig > 0)
 449                 syslog(LOG_ERR, "going down on signal %d", sig);
 450         else
 451                 syslog(LOG_ERR, "going down with fatal error");
 452         BpfClose();
 453         exit(1);
 454 }
 455
 456 /*
 457 **  ReConfig -- Get new list of boot files and reread config files.
 458 **
 459 **      Parameters:
 460 **              None.
 461 **
 462 **      Returns:
 463 **              Nothing.
 464 **
 465 **      Side Effects:
 466 **              - All active connections are dropped.
 467 **              - List of boot-able files is changed.
 468 **              - List of clients is changed.
 469 **
 470 **      Warnings:
 471 **              - This routine must be called with SIGHUP blocked.
 472 */
 473 void
 474 ReConfig(signo)
 475         int signo;
 476 {
 477         syslog(LOG_NOTICE, "reconfiguring boot server");
 478
 479         FreeConns();
 480
 481         if (GetBootFiles() == 0)
 482                 Exit(0);
 483
 484         if (ParseConfig() == 0)
 485                 Exit(0);
 486 }
 487
 488 /*
 489 **  DebugOff -- Turn off debugging.
 490 **
 491 **      Parameters:
 492 **              None.
 493 **
 494 **      Returns:
 495 **              Nothing.
 496 **
 497 **      Side Effects:
 498 **              - Debug file is closed.
 499 */
 500 void
 501 DebugOff(signo)
 502         int signo;
 503 {
 504         if (DbgFp != NULL)
 505                 (void) fclose(DbgFp);
 506
 507         DbgFp = NULL;
 508 }
 509
 510 /*
 511 **  DebugOn -- Turn on debugging.
 512 **
 513 **      Parameters:
 514 **              None.
 515 **
 516 **      Returns:
 517 **              Nothing.
 518 **
 519 **      Side Effects:
 520 **              - Debug file is opened/truncated if not already opened,
 521 **                otherwise do nothing.
 522 */
 523 void
 524 DebugOn(signo)
 525         int signo;
 526 {
 527         if (DbgFp == NULL) {
 528                 if ((DbgFp = fopen(DbgFile, "w")) == NULL)
 529                         syslog(LOG_ERR, "can't open debug file (%s)", DbgFile);
 530         }
 531 }