sbin/routed/main.c

   1 /*
   2  * Copyright (c) 1983, 1988, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  * $FreeBSD: src/sbin/routed/main.c,v 1.11.2.1 2000/08/14 17:00:03 sheldonh Exp $
  30  */
  31
  32 #include "defs.h"
  33 #include "pathnames.h"
  34 #include <signal.h>
  35 #include <fcntl.h>
  36 #include <sys/file.h>
  37
  38 #if !defined(__NetBSD__)
  39 char copyright[] =
  40 "@(#) Copyright (c) 1983, 1988, 1993\n\
  41         The Regents of the University of California.  All rights reserved.\n";
  42 static char sccsid[] __attribute__((unused)) = "@(#)main.c      8.1 (Berkeley) 6/5/93";
  43 #elif defined(__NetBSD__)
  44 __RCSID("$NetBSD$");
  45 __COPYRIGHT("@(#) Copyright (c) 1983, 1988, 1993\n\
  46         The Regents of the University of California.  All rights reserved.\n");
  47 #endif
  48
  49
  50 pid_t   mypid;
  51
  52 naddr   myaddr;                         /* system address */
  53 char    myname[MAXHOSTNAMELEN+1];
  54
  55 int     verbose;
  56
  57 int     supplier;                       /* supply or broadcast updates */
  58 int     supplier_set;
  59 int     ipforwarding = 1;               /* kernel forwarding on */
  60
  61 int     default_gateway;                /* 1=advertise default */
  62 int     background = 1;
  63 int     ridhosts;                       /* 1=reduce host routes */
  64 int     mhome;                          /* 1=want multi-homed host route */
  65 int     advertise_mhome;                /* 1=must continue advertising it */
  66 int     auth_ok = 1;                    /* 1=ignore auth if we do not care */
  67
  68 struct timeval epoch;                   /* when started */
  69 struct timeval clk, prev_clk;
  70 static int usec_fudge;
  71 struct timeval now;                     /* current idea of time */
  72 time_t  now_stale;
  73 time_t  now_expire;
  74 time_t  now_garbage;
  75
  76 struct timeval next_bcast;              /* next general broadcast */
  77 struct timeval no_flash = {             /* inhibit flash update */
  78         EPOCH+SUPPLY_INTERVAL, 0
  79 };
  80
  81 struct timeval flush_kern_timer;
  82
  83 fd_set  fdbits;
  84 int     sock_max;
  85 int     rip_sock = -1;                  /* RIP socket */
  86 struct interface *rip_sock_mcast;       /* current multicast interface */
  87 int     rt_sock;                        /* routing socket */
  88 int     rt_sock_seqno;
  89
  90
  91 static  int get_rip_sock(naddr, int);
  92 static void timevalsub(struct timeval *, struct timeval *, struct timeval *);
  93
  94 int
  95 main(int argc,
  96      char *argv[])
  97 {
  98         int n, mib[4], off;
  99         size_t len;
 100         char *p, *q;
 101         const char *cp;
 102         struct timeval wtime, t2;
 103         time_t dt;
 104         fd_set ibits;
 105         naddr p_net, p_mask;
 106         struct interface *ifp;
 107         struct parm parm;
 108         char *tracename = 0;
 109
 110
 111         /* Some shells are badly broken and send SIGHUP to backgrounded
 112          * processes.
 113          */
 114         signal(SIGHUP, SIG_IGN);
 115
 116         openlog("routed", LOG_PID | LOG_ODELAY, LOG_DAEMON);
 117         ftrace = stdout;
 118
 119         gettimeofday(&clk, 0);
 120         prev_clk = clk;
 121         epoch = clk;
 122         epoch.tv_sec -= EPOCH;
 123         now.tv_sec = EPOCH;
 124         now_stale = EPOCH - STALE_TIME;
 125         now_expire = EPOCH - EXPIRE_TIME;
 126         now_garbage = EPOCH - GARBAGE_TIME;
 127         wtime.tv_sec = 0;
 128
 129         gethostname(myname, sizeof(myname)-1);
 130         gethost(myname, &myaddr);
 131
 132         while ((n = getopt(argc, argv, "sqdghmpAtvT:F:P:")) != -1) {
 133                 switch (n) {
 134                 case 's':
 135                         supplier = 1;
 136                         supplier_set = 1;
 137                         break;
 138
 139                 case 'q':
 140                         supplier = 0;
 141                         supplier_set = 1;
 142                         break;
 143
 144                 case 'd':
 145                         background = 0;
 146                         break;
 147
 148                 case 'g':
 149                         memset(&parm, 0, sizeof(parm));
 150                         parm.parm_d_metric = 1;
 151                         cp = check_parms(&parm);
 152                         if (cp != 0)
 153                                 msglog("bad -g: %s", cp);
 154                         else
 155                                 default_gateway = 1;
 156                         break;
 157
 158                 case 'h':               /* suppress extra host routes */
 159                         ridhosts = 1;
 160                         break;
 161
 162                 case 'm':               /* advertise host route */
 163                         mhome = 1;      /* on multi-homed hosts */
 164                         break;
 165
 166                 case 'A':
 167                         /* Ignore authentication if we do not care.
 168                          * Crazy as it is, that is what RFC 1723 requires.
 169                          */
 170                         auth_ok = 0;
 171                         break;
 172
 173                 case 't':
 174                         new_tracelevel++;
 175                         break;
 176
 177                 case 'T':
 178                         tracename = optarg;
 179                         break;
 180
 181                 case 'F':               /* minimal routes for SLIP */
 182                         n = FAKE_METRIC;
 183                         p = strchr(optarg,',');
 184                         if (p && *p != '\0') {
 185                                 n = (int)strtoul(p+1, &q, 0);
 186                                 if (*q == '\0'
 187                                     && n <= HOPCNT_INFINITY-1
 188                                     && n >= 1)
 189                                         *p = '\0';
 190                         }
 191                         if (!getnet(optarg, &p_net, &p_mask)) {
 192                                 msglog("bad network; \"-F %s\"",
 193                                        optarg);
 194                                 break;
 195                         }
 196                         memset(&parm, 0, sizeof(parm));
 197                         parm.parm_net = p_net;
 198                         parm.parm_mask = p_mask;
 199                         parm.parm_d_metric = n;
 200                         cp = check_parms(&parm);
 201                         if (cp != 0)
 202                                 msglog("bad -F: %s", cp);
 203                         break;
 204
 205                 case 'P':
 206                         /* handle arbitrary parameters.
 207                          */
 208                         q = strdup(optarg);
 209                         cp = parse_parms(q, 0);
 210                         if (cp != 0)
 211                                 msglog("%s in \"-P %s\"", cp, optarg);
 212                         free(q);
 213                         break;
 214
 215                 case 'v':
 216                         /* display version */
 217                         verbose++;
 218                         msglog("version 2.22");
 219                         break;
 220
 221                 default:
 222                         goto usage;
 223                 }
 224         }
 225         argc -= optind;
 226         argv += optind;
 227
 228         if (tracename == 0 && argc >= 1) {
 229                 tracename = *argv++;
 230                 argc--;
 231         }
 232         if (tracename != 0 && tracename[0] == '\0')
 233                 goto usage;
 234         if (argc != 0) {
 235 usage:
 236                 logbad(0, "usage: routed [-sqdghmpAtv] [-T tracefile]"
 237                        " [-F net[,metric]] [-P parms]");
 238         }
 239         if (geteuid() != 0) {
 240                 if (verbose)
 241                         exit(0);
 242                 logbad(0, "requires UID 0");
 243         }
 244
 245         mib[0] = CTL_NET;
 246         mib[1] = PF_INET;
 247         mib[2] = IPPROTO_IP;
 248         mib[3] = IPCTL_FORWARDING;
 249         len = sizeof(ipforwarding);
 250         if (sysctl(mib, 4, &ipforwarding, &len, 0, 0) < 0)
 251                 LOGERR("sysctl(IPCTL_FORWARDING)");
 252
 253         if (!ipforwarding) {
 254                 if (supplier)
 255                         msglog("-s incompatible with ipforwarding=0");
 256                 if (default_gateway) {
 257                         msglog("-g incompatible with ipforwarding=0");
 258                         default_gateway = 0;
 259                 }
 260                 supplier = 0;
 261                 supplier_set = 1;
 262         }
 263         if (default_gateway) {
 264                 if (supplier_set && !supplier) {
 265                         msglog("-g and -q incompatible");
 266                 } else {
 267                         supplier = 1;
 268                         supplier_set = 1;
 269                 }
 270         }
 271
 272
 273         signal(SIGALRM, sigalrm);
 274         if (!background)
 275                 signal(SIGHUP, sigterm);    /* SIGHUP fatal during debugging */
 276         signal(SIGTERM, sigterm);
 277         signal(SIGINT, sigterm);
 278         signal(SIGUSR1, sigtrace_on);
 279         signal(SIGUSR2, sigtrace_off);
 280
 281         /* get into the background */
 282         if (background && daemon(0, 1) < 0)
 283                 BADERR(0,"daemon()");
 284
 285         mypid = getpid();
 286         srandom((int)(clk.tv_sec ^ clk.tv_usec ^ mypid));
 287
 288         /* prepare socket connected to the kernel.
 289          */
 290         rt_sock = socket(AF_ROUTE, SOCK_RAW, 0);
 291         if (rt_sock < 0)
 292                 BADERR(1,"rt_sock = socket()");
 293         if (fcntl(rt_sock, F_SETFL, O_NONBLOCK) == -1)
 294                 logbad(1, "fcntl(rt_sock) O_NONBLOCK: %s", strerror(errno));
 295         off = 0;
 296         if (setsockopt(rt_sock, SOL_SOCKET,SO_USELOOPBACK,
 297                        &off,sizeof(off)) < 0)
 298                 LOGERR("setsockopt(SO_USELOOPBACK,0)");
 299
 300         fix_select();
 301
 302
 303         if (tracename != 0) {
 304                 strncpy(inittracename, tracename, sizeof(inittracename)-1);
 305                 set_tracefile(inittracename, "%s", -1);
 306         } else {
 307                 tracelevel_msg("%s", -1);   /* turn on tracing to stdio */
 308         }
 309
 310         bufinit();
 311
 312         /* initialize radix tree */
 313         rtinit();
 314
 315         /* Pick a random part of the second for our output to minimize
 316          * collisions.
 317          *
 318          * Start broadcasting after hearing from other routers, and
 319          * at a random time so a bunch of systems do not get synchronized
 320          * after a power failure.
 321          */
 322         intvl_random(&next_bcast, EPOCH+MIN_WAITTIME, EPOCH+SUPPLY_INTERVAL);
 323         age_timer.tv_usec = next_bcast.tv_usec;
 324         age_timer.tv_sec = EPOCH+MIN_WAITTIME;
 325         rdisc_timer = next_bcast;
 326         ifinit_timer.tv_usec = next_bcast.tv_usec;
 327
 328         /* Collect an initial view of the world by checking the interface
 329          * configuration and the kludge file.
 330          */
 331         gwkludge();
 332         ifinit();
 333
 334         /* Ask for routes */
 335         rip_query();
 336         rdisc_sol();
 337
 338         /* Now turn off stdio if not tracing */
 339         if (new_tracelevel == 0)
 340                 trace_close(background);
 341
 342         /* Loop forever, listening and broadcasting.
 343          */
 344         for (;;) {
 345                 prev_clk = clk;
 346                 gettimeofday(&clk, 0);
 347                 if (prev_clk.tv_sec == clk.tv_sec
 348                     && prev_clk.tv_usec == clk.tv_usec+usec_fudge) {
 349                         /* Much of `routed` depends on time always advancing.
 350                          * On systems that do not guarantee that gettimeofday()
 351                          * produces unique timestamps even if called within
 352                          * a single tick, use trickery like that in classic
 353                          * BSD kernels.
 354                          */
 355                         clk.tv_usec += ++usec_fudge;
 356
 357                 } else {
 358                         usec_fudge = 0;
 359
 360                         timevalsub(&t2, &clk, &prev_clk);
 361                         if (t2.tv_sec < 0
 362                             || t2.tv_sec > wtime.tv_sec + 5) {
 363                                 /* Deal with time changes before other
 364                                  * housekeeping to keep everything straight.
 365                                  */
 366                                 dt = t2.tv_sec;
 367                                 if (dt > 0)
 368                                         dt -= wtime.tv_sec;
 369                                 trace_act("time changed by %d sec", (int)dt);
 370                                 epoch.tv_sec += dt;
 371                         }
 372                 }
 373                 timevalsub(&now, &clk, &epoch);
 374                 now_stale = now.tv_sec - STALE_TIME;
 375                 now_expire = now.tv_sec - EXPIRE_TIME;
 376                 now_garbage = now.tv_sec - GARBAGE_TIME;
 377
 378                 /* deal with signals that should affect tracing */
 379                 set_tracelevel();
 380
 381                 if (stopint != 0) {
 382                         rip_bcast(0);
 383                         rdisc_adv();
 384                         trace_off("exiting with signal %d", stopint);
 385                         exit(stopint | 128);
 386                 }
 387
 388                 /* look for new or dead interfaces */
 389                 timevalsub(&wtime, &ifinit_timer, &now);
 390                 if (wtime.tv_sec <= 0) {
 391                         wtime.tv_sec = 0;
 392                         ifinit();
 393                         rip_query();
 394                         continue;
 395                 }
 396
 397                 /* Check the kernel table occassionally for mysteriously
 398                  * evaporated routes
 399                  */
 400                 timevalsub(&t2, &flush_kern_timer, &now);
 401                 if (t2.tv_sec <= 0) {
 402                         flush_kern();
 403                         flush_kern_timer.tv_sec = (now.tv_sec
 404                                                    + CHECK_QUIET_INTERVAL);
 405                         continue;
 406                 }
 407                 if (timercmp(&t2, &wtime, <))
 408                         wtime = t2;
 409
 410                 /* If it is time, then broadcast our routes.
 411                  */
 412                 if (supplier || advertise_mhome) {
 413                         timevalsub(&t2, &next_bcast, &now);
 414                         if (t2.tv_sec <= 0) {
 415                                 /* Synchronize the aging and broadcast
 416                                  * timers to minimize awakenings
 417                                  */
 418                                 age(0);
 419
 420                                 rip_bcast(0);
 421
 422                                 /* It is desirable to send routing updates
 423                                  * regularly.  So schedule the next update
 424                                  * 30 seconds after the previous one was
 425                                  * scheduled, instead of 30 seconds after
 426                                  * the previous update was finished.
 427                                  * Even if we just started after discovering
 428                                  * a 2nd interface or were otherwise delayed,
 429                                  * pick a 30-second aniversary of the
 430                                  * original broadcast time.
 431                                  */
 432                                 n = 1 + (0-t2.tv_sec)/SUPPLY_INTERVAL;
 433                                 next_bcast.tv_sec += n*SUPPLY_INTERVAL;
 434
 435                                 continue;
 436                         }
 437
 438                         if (timercmp(&t2, &wtime, <))
 439                                 wtime = t2;
 440                 }
 441
 442                 /* If we need a flash update, either do it now or
 443                  * set the delay to end when it is time.
 444                  *
 445                  * If we are within MIN_WAITTIME seconds of a full update,
 446                  * do not bother.
 447                  */
 448                 if (need_flash
 449                     && supplier
 450                     && no_flash.tv_sec+MIN_WAITTIME < next_bcast.tv_sec) {
 451                         /* accurate to the millisecond */
 452                         if (!timercmp(&no_flash, &now, >))
 453                                 rip_bcast(1);
 454                         timevalsub(&t2, &no_flash, &now);
 455                         if (timercmp(&t2, &wtime, <))
 456                                 wtime = t2;
 457                 }
 458
 459                 /* trigger the main aging timer.
 460                  */
 461                 timevalsub(&t2, &age_timer, &now);
 462                 if (t2.tv_sec <= 0) {
 463                         age(0);
 464                         continue;
 465                 }
 466                 if (timercmp(&t2, &wtime, <))
 467                         wtime = t2;
 468
 469                 /* update the kernel routing table
 470                  */
 471                 timevalsub(&t2, &need_kern, &now);
 472                 if (t2.tv_sec <= 0) {
 473                         age(0);
 474                         continue;
 475                 }
 476                 if (timercmp(&t2, &wtime, <))
 477                         wtime = t2;
 478
 479                 /* take care of router discovery,
 480                  * but do it in the correct the millisecond
 481                  */
 482                 if (!timercmp(&rdisc_timer, &now, >)) {
 483                         rdisc_age(0);
 484                         continue;
 485                 }
 486                 timevalsub(&t2, &rdisc_timer, &now);
 487                 if (timercmp(&t2, &wtime, <))
 488                         wtime = t2;
 489
 490
 491                 /* wait for input or a timer to expire.
 492                  */
 493                 trace_flush();
 494                 ibits = fdbits;
 495                 n = select(sock_max, &ibits, 0, 0, &wtime);
 496                 if (n <= 0) {
 497                         if (n < 0 && errno != EINTR && errno != EAGAIN)
 498                                 BADERR(1,"select");
 499                         continue;
 500                 }
 501
 502                 if (FD_ISSET(rt_sock, &ibits)) {
 503                         read_rt();
 504                         n--;
 505                 }
 506                 if (rdisc_sock >= 0 && FD_ISSET(rdisc_sock, &ibits)) {
 507                         read_d();
 508                         n--;
 509                 }
 510                 if (rip_sock >= 0 && FD_ISSET(rip_sock, &ibits)) {
 511                         read_rip(rip_sock, 0);
 512                         n--;
 513                 }
 514
 515                 for (ifp = ifnet; n > 0 && 0 != ifp; ifp = ifp->int_next) {
 516                         if (ifp->int_rip_sock >= 0
 517                             && FD_ISSET(ifp->int_rip_sock, &ibits)) {
 518                                 read_rip(ifp->int_rip_sock, ifp);
 519                                 n--;
 520                         }
 521                 }
 522         }
 523 }
 524
 525
 526 /* ARGSUSED */
 527 void
 528 sigalrm(int s UNUSED)
 529 {
 530         /* Historically, SIGALRM would cause the daemon to check for
 531          * new and broken interfaces.
 532          */
 533         ifinit_timer.tv_sec = now.tv_sec;
 534         trace_act("SIGALRM");
 535 }
 536
 537
 538 /* watch for fatal signals */
 539 void
 540 sigterm(int sig)
 541 {
 542         stopint = sig;
 543         signal(sig, SIG_DFL);   /* catch it only once */
 544 }
 545
 546
 547 void
 548 fix_select(void)
 549 {
 550         struct interface *ifp;
 551
 552
 553         FD_ZERO(&fdbits);
 554         sock_max = 0;
 555
 556         FD_SET(rt_sock, &fdbits);
 557         if (sock_max <= rt_sock)
 558                 sock_max = rt_sock+1;
 559         if (rip_sock >= 0) {
 560                 FD_SET(rip_sock, &fdbits);
 561                 if (sock_max <= rip_sock)
 562                         sock_max = rip_sock+1;
 563         }
 564         for (ifp = ifnet; NULL != ifp; ifp = ifp->int_next) {
 565                 if (ifp->int_rip_sock >= 0) {
 566                         FD_SET(ifp->int_rip_sock, &fdbits);
 567                         if (sock_max <= ifp->int_rip_sock)
 568                                 sock_max = ifp->int_rip_sock+1;
 569                 }
 570         }
 571         if (rdisc_sock >= 0) {
 572                 FD_SET(rdisc_sock, &fdbits);
 573                 if (sock_max <= rdisc_sock)
 574                         sock_max = rdisc_sock+1;
 575         }
 576 }
 577
 578
 579 void
 580 fix_sock(int sock,
 581          const char *name)
 582 {
 583         int on;
 584 #define MIN_SOCKBUF (4*1024)
 585         static int rbuf;
 586
 587         if (fcntl(sock, F_SETFL, O_NONBLOCK) == -1)
 588                 logbad(1, "fcntl(%s) O_NONBLOCK: %s",
 589                        name, strerror(errno));
 590         on = 1;
 591         if (setsockopt(sock, SOL_SOCKET,SO_BROADCAST, &on,sizeof(on)) < 0)
 592                 msglog("setsockopt(%s,SO_BROADCAST): %s",
 593                        name, strerror(errno));
 594 #ifdef USE_PASSIFNAME
 595         on = 1;
 596         if (setsockopt(sock, SOL_SOCKET, SO_PASSIFNAME, &on,sizeof(on)) < 0)
 597                 msglog("setsockopt(%s,SO_PASSIFNAME): %s",
 598                        name, strerror(errno));
 599 #endif
 600
 601         if (rbuf >= MIN_SOCKBUF) {
 602                 if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
 603                                &rbuf, sizeof(rbuf)) < 0)
 604                         msglog("setsockopt(%s,SO_RCVBUF=%d): %s",
 605                                name, rbuf, strerror(errno));
 606         } else {
 607                 for (rbuf = 60*1024; ; rbuf -= 4096) {
 608                         if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
 609                                        &rbuf, sizeof(rbuf)) == 0) {
 610                                 trace_act("RCVBUF=%d", rbuf);
 611                                 break;
 612                         }
 613                         if (rbuf < MIN_SOCKBUF) {
 614                                 msglog("setsockopt(%s,SO_RCVBUF = %d): %s",
 615                                        name, rbuf, strerror(errno));
 616                                 break;
 617                         }
 618                 }
 619         }
 620 }
 621
 622
 623 /* get a rip socket
 624  */
 625 static int                              /* <0 or file descriptor */
 626 get_rip_sock(naddr addr,
 627              int serious)               /* 1=failure to bind is serious */
 628 {
 629         struct sockaddr_in in;
 630         unsigned char ttl;
 631         int s;
 632
 633
 634         if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
 635                 BADERR(1,"rip_sock = socket()");
 636
 637         memset(&in, 0, sizeof(in));
 638 #ifdef _HAVE_SIN_LEN
 639         in.sin_len = sizeof(in);
 640 #endif
 641         in.sin_family = AF_INET;
 642         in.sin_port = htons(RIP_PORT);
 643         in.sin_addr.s_addr = addr;
 644         if (bind(s, (struct sockaddr *)&in, sizeof(in)) < 0) {
 645                 if (serious)
 646                         BADERR(errno != EADDRINUSE, "bind(rip_sock)");
 647                 return -1;
 648         }
 649         fix_sock(s,"rip_sock");
 650
 651         ttl = 1;
 652         if (setsockopt(s, IPPROTO_IP, IP_MULTICAST_TTL,
 653                        &ttl, sizeof(ttl)) < 0)
 654                 DBGERR(1,"rip_sock setsockopt(IP_MULTICAST_TTL)");
 655
 656         return s;
 657 }
 658
 659
 660 /* turn off main RIP socket */
 661 void
 662 rip_off(void)
 663 {
 664         struct interface *ifp;
 665         naddr addr;
 666
 667
 668         if (rip_sock >= 0 && !mhome) {
 669                 trace_act("turn off RIP");
 670
 671                 close(rip_sock);
 672                 rip_sock = -1;
 673
 674                 /* get non-broadcast sockets to listen to queries.
 675                  */
 676                 for (ifp = ifnet; ifp != NULL; ifp = ifp->int_next) {
 677                         if (ifp->int_state & IS_REMOTE)
 678                                 continue;
 679                         if (ifp->int_rip_sock < 0) {
 680                                 addr = ((ifp->int_if_flags & IFF_POINTOPOINT)
 681                                         ? ifp->int_dstaddr
 682                                         : ifp->int_addr);
 683                                 ifp->int_rip_sock = get_rip_sock(addr, 0);
 684                         }
 685                 }
 686
 687                 fix_select();
 688
 689                 age(0);
 690         }
 691 }
 692
 693
 694 /* turn on RIP multicast input via an interface
 695  */
 696 static void
 697 rip_mcast_on(struct interface *ifp)
 698 {
 699         struct ip_mreq m;
 700
 701         if (!IS_RIP_IN_OFF(ifp->int_state)
 702             && (ifp->int_if_flags & IFF_MULTICAST)
 703 #ifdef MCAST_PPP_BUG
 704             && !(ifp->int_if_flags & IFF_POINTOPOINT)
 705 #endif
 706             && !(ifp->int_state & IS_ALIAS)) {
 707                 m.imr_multiaddr.s_addr = htonl(INADDR_RIP_GROUP);
 708                 m.imr_interface.s_addr = ((ifp->int_if_flags & IFF_POINTOPOINT)
 709                                           ? ifp->int_dstaddr
 710                                           : ifp->int_addr);
 711                 if (setsockopt(rip_sock,IPPROTO_IP, IP_ADD_MEMBERSHIP,
 712                                &m, sizeof(m)) < 0)
 713                         LOGERR("setsockopt(IP_ADD_MEMBERSHIP RIP)");
 714         }
 715 }
 716
 717
 718 /* Prepare socket used for RIP.
 719  */
 720 void
 721 rip_on(struct interface *ifp)
 722 {
 723         /* If the main RIP socket is already alive, only start receiving
 724          * multicasts for this interface.
 725          */
 726         if (rip_sock >= 0) {
 727                 if (ifp != NULL)
 728                         rip_mcast_on(ifp);
 729                 return;
 730         }
 731
 732         /* If the main RIP socket is off and it makes sense to turn it on,
 733          * then turn it on for all of the interfaces.
 734          * It makes sense if either router discovery is off, or if
 735          * router discover is on and at most one interface is doing RIP.
 736          */
 737         if (rip_interfaces > 0 && (!rdisc_ok || rip_interfaces > 1)) {
 738                 trace_act("turn on RIP");
 739
 740                 /* Close all of the query sockets so that we can open
 741                  * the main socket.  SO_REUSEPORT is not a solution,
 742                  * since that would let two daemons bind to the broadcast
 743                  * socket.
 744                  */
 745                 for (ifp = ifnet; ifp != NULL; ifp = ifp->int_next) {
 746                         if (ifp->int_rip_sock >= 0) {
 747                                 close(ifp->int_rip_sock);
 748                                 ifp->int_rip_sock = -1;
 749                         }
 750                 }
 751
 752                 rip_sock = get_rip_sock(INADDR_ANY, 1);
 753                 rip_sock_mcast = NULL;
 754
 755                 /* Do not advertise anything until we have heard something
 756                  */
 757                 if (next_bcast.tv_sec < now.tv_sec+MIN_WAITTIME)
 758                         next_bcast.tv_sec = now.tv_sec+MIN_WAITTIME;
 759
 760                 for (ifp = ifnet; ifp != NULL; ifp = ifp->int_next) {
 761                         ifp->int_query_time = NEVER;
 762                         rip_mcast_on(ifp);
 763                 }
 764                 ifinit_timer.tv_sec = now.tv_sec;
 765
 766         } else if (ifp != NULL
 767                    && !(ifp->int_state & IS_REMOTE)
 768                    && ifp->int_rip_sock < 0) {
 769                 /* RIP is off, so ensure there are sockets on which
 770                  * to listen for queries.
 771                  */
 772                 ifp->int_rip_sock = get_rip_sock(ifp->int_addr, 0);
 773         }
 774
 775         fix_select();
 776 }
 777
 778
 779 /* die if malloc(3) fails
 780  */
 781 void *
 782 rtmalloc(size_t size,
 783          const char *msg)
 784 {
 785         void *p = malloc(size);
 786         if (p == NULL)
 787                 logbad(1,"malloc(%lu) failed in %s", (u_long)size, msg);
 788         return p;
 789 }
 790
 791
 792 /* get a random instant in an interval
 793  */
 794 void
 795 intvl_random(struct timeval *tp,        /* put value here */
 796              u_long lo,                 /* value is after this second */
 797              u_long hi)                 /* and before this */
 798 {
 799         tp->tv_sec = (time_t)(hi == lo
 800                               ? lo
 801                               : (lo + random() % ((hi - lo))));
 802         tp->tv_usec = random() % 1000000;
 803 }
 804
 805
 806 void
 807 timevaladd(struct timeval *t1,
 808            struct timeval *t2)
 809 {
 810
 811         t1->tv_sec += t2->tv_sec;
 812         if ((t1->tv_usec += t2->tv_usec) >= 1000000) {
 813                 t1->tv_sec++;
 814                 t1->tv_usec -= 1000000;
 815         }
 816 }
 817
 818
 819 /* t1 = t2 - t3
 820  */
 821 static void
 822 timevalsub(struct timeval *t1,
 823            struct timeval *t2,
 824            struct timeval *t3)
 825 {
 826         t1->tv_sec = t2->tv_sec - t3->tv_sec;
 827         if ((t1->tv_usec = t2->tv_usec - t3->tv_usec) < 0) {
 828                 t1->tv_sec--;
 829                 t1->tv_usec += 1000000;
 830         }
 831 }
 832
 833
 834 /* put a message into the system log
 835  */
 836 void
 837 msglog(const char *p, ...)
 838 {
 839         va_list args;
 840
 841         trace_flush();
 842
 843         va_start(args, p);
 844         vsyslog(LOG_ERR, p, args);
 845
 846         if (ftrace != 0) {
 847                 if (ftrace == stdout)
 848                         fputs("routed: ", ftrace);
 849                 vfprintf(ftrace, p, args);
 850                 fputc('\n', ftrace);
 851         }
 852 }
 853
 854
 855 /* Put a message about a bad system into the system log if
 856  * we have not complained about it recently.
 857  *
 858  * It is desirable to complain about all bad systems, but not too often.
 859  * In the worst case, it is not practical to keep track of all bad systems.
 860  * For example, there can be many systems with the wrong password.
 861  */
 862 void
 863 msglim(struct msg_limit *lim, naddr addr, const char *p, ...)
 864 {
 865         va_list args;
 866         int i;
 867         struct msg_sub *ms1, *ms;
 868         const char *p1;
 869
 870         va_start(args, p);
 871
 872         /* look for the oldest slot in the table
 873          * or the slot for the bad router.
 874          */
 875         ms = ms1 = lim->subs;
 876         for (i = MSG_SUBJECT_N; ; i--, ms1++) {
 877                 if (i == 0) {
 878                         /* Reuse a slot at most once every 10 minutes.
 879                          */
 880                         if (lim->reuse > now.tv_sec) {
 881                                 ms = NULL;
 882                         } else {
 883                                 ms = ms1;
 884                                 lim->reuse = now.tv_sec + 10*60;
 885                         }
 886                         break;
 887                 }
 888                 if (ms->addr == addr) {
 889                         /* Repeat a complaint about a given system at
 890                          * most once an hour.
 891                          */
 892                         if (ms->until > now.tv_sec)
 893                                 ms = NULL;
 894                         break;
 895                 }
 896                 if (ms->until < ms1->until)
 897                         ms = ms1;
 898         }
 899         if (ms != NULL) {
 900                 ms->addr = addr;
 901                 ms->until = now.tv_sec + 60*60; /* 60 minutes */
 902
 903                 trace_flush();
 904                 for (p1 = p; *p1 == ' '; p1++)
 905                         continue;
 906                 vsyslog(LOG_ERR, p1, args);
 907         }
 908
 909         /* always display the message if tracing */
 910         if (ftrace != 0) {
 911                 vfprintf(ftrace, p, args);
 912                 fputc('\n', ftrace);
 913         }
 914 }
 915
 916
 917 void
 918 logbad(int dump, const char *p, ...)
 919 {
 920         va_list args;
 921
 922         trace_flush();
 923
 924         va_start(args, p);
 925         vsyslog(LOG_ERR, p, args);
 926
 927         fputs("routed: ", stderr);
 928         vfprintf(stderr, p, args);
 929         fputs("; giving up\n",stderr);
 930         fflush(stderr);
 931
 932         if (dump)
 933                 abort();
 934         exit(1);
 935 }