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 #ifdef sgi
  35 #include "math.h"
  36 #endif
  37 #include <signal.h>
  38 #include <fcntl.h>
  39 #include <sys/file.h>
  40
  41 #if !defined(sgi) && !defined(__NetBSD__)
  42 char copyright[] =
  43 "@(#) Copyright (c) 1983, 1988, 1993\n\
  44         The Regents of the University of California.  All rights reserved.\n";
  45 static char sccsid[] __attribute__((unused)) = "@(#)main.c      8.1 (Berkeley) 6/5/93";
  46 #elif defined(__NetBSD__)
  47 __RCSID("$NetBSD$");
  48 __COPYRIGHT("@(#) Copyright (c) 1983, 1988, 1993\n\
  49         The Regents of the University of California.  All rights reserved.\n");
  50 #endif
  51
  52
  53 pid_t   mypid;
  54
  55 naddr   myaddr;                         /* system address */
  56 char    myname[MAXHOSTNAMELEN+1];
  57
  58 int     verbose;
  59
  60 int     supplier;                       /* supply or broadcast updates */
  61 int     supplier_set;
  62 int     ipforwarding = 1;               /* kernel forwarding on */
  63
  64 int     default_gateway;                /* 1=advertise default */
  65 int     background = 1;
  66 int     ridhosts;                       /* 1=reduce host routes */
  67 int     mhome;                          /* 1=want multi-homed host route */
  68 int     advertise_mhome;                /* 1=must continue advertising it */
  69 int     auth_ok = 1;                    /* 1=ignore auth if we do not care */
  70
  71 struct timeval epoch;                   /* when started */
  72 struct timeval clk, prev_clk;
  73 static int usec_fudge;
  74 struct timeval now;                     /* current idea of time */
  75 time_t  now_stale;
  76 time_t  now_expire;
  77 time_t  now_garbage;
  78
  79 struct timeval next_bcast;              /* next general broadcast */
  80 struct timeval no_flash = {             /* inhibit flash update */
  81         EPOCH+SUPPLY_INTERVAL, 0
  82 };
  83
  84 struct timeval flush_kern_timer;
  85
  86 fd_set  fdbits;
  87 int     sock_max;
  88 int     rip_sock = -1;                  /* RIP socket */
  89 struct interface *rip_sock_mcast;       /* current multicast interface */
  90 int     rt_sock;                        /* routing socket */
  91 int     rt_sock_seqno;
  92
  93
  94 static  int get_rip_sock(naddr, int);
  95 static void timevalsub(struct timeval *, struct timeval *, struct timeval *);
  96
  97 int
  98 main(int argc,
  99      char *argv[])
 100 {
 101         int n, mib[4], off;
 102         size_t len;
 103         char *p, *q;
 104         const char *cp;
 105         struct timeval wtime, t2;
 106         time_t dt;
 107         fd_set ibits;
 108         naddr p_net, p_mask;
 109         struct interface *ifp;
 110         struct parm parm;
 111         char *tracename = 0;
 112
 113
 114         /* Some shells are badly broken and send SIGHUP to backgrounded
 115          * processes.
 116          */
 117         signal(SIGHUP, SIG_IGN);
 118
 119         openlog("routed", LOG_PID | LOG_ODELAY, LOG_DAEMON);
 120         ftrace = stdout;
 121
 122         gettimeofday(&clk, 0);
 123         prev_clk = clk;
 124         epoch = clk;
 125         epoch.tv_sec -= EPOCH;
 126         now.tv_sec = EPOCH;
 127         now_stale = EPOCH - STALE_TIME;
 128         now_expire = EPOCH - EXPIRE_TIME;
 129         now_garbage = EPOCH - GARBAGE_TIME;
 130         wtime.tv_sec = 0;
 131
 132         gethostname(myname, sizeof(myname)-1);
 133         gethost(myname, &myaddr);
 134
 135         while ((n = getopt(argc, argv, "sqdghmpAtvT:F:P:")) != -1) {
 136                 switch (n) {
 137                 case 's':
 138                         supplier = 1;
 139                         supplier_set = 1;
 140                         break;
 141
 142                 case 'q':
 143                         supplier = 0;
 144                         supplier_set = 1;
 145                         break;
 146
 147                 case 'd':
 148                         background = 0;
 149                         break;
 150
 151                 case 'g':
 152                         memset(&parm, 0, sizeof(parm));
 153                         parm.parm_d_metric = 1;
 154                         cp = check_parms(&parm);
 155                         if (cp != 0)
 156                                 msglog("bad -g: %s", cp);
 157                         else
 158                                 default_gateway = 1;
 159                         break;
 160
 161                 case 'h':               /* suppress extra host routes */
 162                         ridhosts = 1;
 163                         break;
 164
 165                 case 'm':               /* advertise host route */
 166                         mhome = 1;      /* on multi-homed hosts */
 167                         break;
 168
 169                 case 'A':
 170                         /* Ignore authentication if we do not care.
 171                          * Crazy as it is, that is what RFC 1723 requires.
 172                          */
 173                         auth_ok = 0;
 174                         break;
 175
 176                 case 't':
 177                         new_tracelevel++;
 178                         break;
 179
 180                 case 'T':
 181                         tracename = optarg;
 182                         break;
 183
 184                 case 'F':               /* minimal routes for SLIP */
 185                         n = FAKE_METRIC;
 186                         p = strchr(optarg,',');
 187                         if (p && *p != '\0') {
 188                                 n = (int)strtoul(p+1, &q, 0);
 189                                 if (*q == '\0'
 190                                     && n <= HOPCNT_INFINITY-1
 191                                     && n >= 1)
 192                                         *p = '\0';
 193                         }
 194                         if (!getnet(optarg, &p_net, &p_mask)) {
 195                                 msglog("bad network; \"-F %s\"",
 196                                        optarg);
 197                                 break;
 198                         }
 199                         memset(&parm, 0, sizeof(parm));
 200                         parm.parm_net = p_net;
 201                         parm.parm_mask = p_mask;
 202                         parm.parm_d_metric = n;
 203                         cp = check_parms(&parm);
 204                         if (cp != 0)
 205                                 msglog("bad -F: %s", cp);
 206                         break;
 207
 208                 case 'P':
 209                         /* handle arbitrary parameters.
 210                          */
 211                         q = strdup(optarg);
 212                         cp = parse_parms(q, 0);
 213                         if (cp != 0)
 214                                 msglog("%s in \"-P %s\"", cp, optarg);
 215                         free(q);
 216                         break;
 217
 218                 case 'v':
 219                         /* display version */
 220                         verbose++;
 221                         msglog("version 2.22");
 222                         break;
 223
 224                 default:
 225                         goto usage;
 226                 }
 227         }
 228         argc -= optind;
 229         argv += optind;
 230
 231         if (tracename == 0 && argc >= 1) {
 232                 tracename = *argv++;
 233                 argc--;
 234         }
 235         if (tracename != 0 && tracename[0] == '\0')
 236                 goto usage;
 237         if (argc != 0) {
 238 usage:
 239                 logbad(0, "usage: routed [-sqdghmpAtv] [-T tracefile]"
 240                        " [-F net[,metric]] [-P parms]");
 241         }
 242         if (geteuid() != 0) {
 243                 if (verbose)
 244                         exit(0);
 245                 logbad(0, "requires UID 0");
 246         }
 247
 248         mib[0] = CTL_NET;
 249         mib[1] = PF_INET;
 250         mib[2] = IPPROTO_IP;
 251         mib[3] = IPCTL_FORWARDING;
 252         len = sizeof(ipforwarding);
 253         if (sysctl(mib, 4, &ipforwarding, &len, 0, 0) < 0)
 254                 LOGERR("sysctl(IPCTL_FORWARDING)");
 255
 256         if (!ipforwarding) {
 257                 if (supplier)
 258                         msglog("-s incompatible with ipforwarding=0");
 259                 if (default_gateway) {
 260                         msglog("-g incompatible with ipforwarding=0");
 261                         default_gateway = 0;
 262                 }
 263                 supplier = 0;
 264                 supplier_set = 1;
 265         }
 266         if (default_gateway) {
 267                 if (supplier_set && !supplier) {
 268                         msglog("-g and -q incompatible");
 269                 } else {
 270                         supplier = 1;
 271                         supplier_set = 1;
 272                 }
 273         }
 274
 275
 276         signal(SIGALRM, sigalrm);
 277         if (!background)
 278                 signal(SIGHUP, sigterm);    /* SIGHUP fatal during debugging */
 279         signal(SIGTERM, sigterm);
 280         signal(SIGINT, sigterm);
 281         signal(SIGUSR1, sigtrace_on);
 282         signal(SIGUSR2, sigtrace_off);
 283
 284         /* get into the background */
 285 #ifdef sgi
 286         if (0 > _daemonize(background ? 0 : (_DF_NOCHDIR|_DF_NOFORK),
 287                            STDIN_FILENO, STDOUT_FILENO, STDERR_FILENO))
 288                 BADERR(0, "_daemonize()");
 289 #else
 290         if (background && daemon(0, 1) < 0)
 291                 BADERR(0,"daemon()");
 292 #endif
 293
 294         mypid = getpid();
 295         srandom((int)(clk.tv_sec ^ clk.tv_usec ^ mypid));
 296
 297         /* prepare socket connected to the kernel.
 298          */
 299         rt_sock = socket(AF_ROUTE, SOCK_RAW, 0);
 300         if (rt_sock < 0)
 301                 BADERR(1,"rt_sock = socket()");
 302         if (fcntl(rt_sock, F_SETFL, O_NONBLOCK) == -1)
 303                 logbad(1, "fcntl(rt_sock) O_NONBLOCK: %s", strerror(errno));
 304         off = 0;
 305         if (setsockopt(rt_sock, SOL_SOCKET,SO_USELOOPBACK,
 306                        &off,sizeof(off)) < 0)
 307                 LOGERR("setsockopt(SO_USELOOPBACK,0)");
 308
 309         fix_select();
 310
 311
 312         if (tracename != 0) {
 313                 strncpy(inittracename, tracename, sizeof(inittracename)-1);
 314                 set_tracefile(inittracename, "%s", -1);
 315         } else {
 316                 tracelevel_msg("%s", -1);   /* turn on tracing to stdio */
 317         }
 318
 319         bufinit();
 320
 321         /* initialize radix tree */
 322         rtinit();
 323
 324         /* Pick a random part of the second for our output to minimize
 325          * collisions.
 326          *
 327          * Start broadcasting after hearing from other routers, and
 328          * at a random time so a bunch of systems do not get synchronized
 329          * after a power failure.
 330          */
 331         intvl_random(&next_bcast, EPOCH+MIN_WAITTIME, EPOCH+SUPPLY_INTERVAL);
 332         age_timer.tv_usec = next_bcast.tv_usec;
 333         age_timer.tv_sec = EPOCH+MIN_WAITTIME;
 334         rdisc_timer = next_bcast;
 335         ifinit_timer.tv_usec = next_bcast.tv_usec;
 336
 337         /* Collect an initial view of the world by checking the interface
 338          * configuration and the kludge file.
 339          */
 340         gwkludge();
 341         ifinit();
 342
 343         /* Ask for routes */
 344         rip_query();
 345         rdisc_sol();
 346
 347         /* Now turn off stdio if not tracing */
 348         if (new_tracelevel == 0)
 349                 trace_close(background);
 350
 351         /* Loop forever, listening and broadcasting.
 352          */
 353         for (;;) {
 354                 prev_clk = clk;
 355                 gettimeofday(&clk, 0);
 356                 if (prev_clk.tv_sec == clk.tv_sec
 357                     && prev_clk.tv_usec == clk.tv_usec+usec_fudge) {
 358                         /* Much of `routed` depends on time always advancing.
 359                          * On systems that do not guarantee that gettimeofday()
 360                          * produces unique timestamps even if called within
 361                          * a single tick, use trickery like that in classic
 362                          * BSD kernels.
 363                          */
 364                         clk.tv_usec += ++usec_fudge;
 365
 366                 } else {
 367                         usec_fudge = 0;
 368
 369                         timevalsub(&t2, &clk, &prev_clk);
 370                         if (t2.tv_sec < 0
 371                             || t2.tv_sec > wtime.tv_sec + 5) {
 372                                 /* Deal with time changes before other
 373                                  * housekeeping to keep everything straight.
 374                                  */
 375                                 dt = t2.tv_sec;
 376                                 if (dt > 0)
 377                                         dt -= wtime.tv_sec;
 378                                 trace_act("time changed by %d sec", (int)dt);
 379                                 epoch.tv_sec += dt;
 380                         }
 381                 }
 382                 timevalsub(&now, &clk, &epoch);
 383                 now_stale = now.tv_sec - STALE_TIME;
 384                 now_expire = now.tv_sec - EXPIRE_TIME;
 385                 now_garbage = now.tv_sec - GARBAGE_TIME;
 386
 387                 /* deal with signals that should affect tracing */
 388                 set_tracelevel();
 389
 390                 if (stopint != 0) {
 391                         rip_bcast(0);
 392                         rdisc_adv();
 393                         trace_off("exiting with signal %d", stopint);
 394                         exit(stopint | 128);
 395                 }
 396
 397                 /* look for new or dead interfaces */
 398                 timevalsub(&wtime, &ifinit_timer, &now);
 399                 if (wtime.tv_sec <= 0) {
 400                         wtime.tv_sec = 0;
 401                         ifinit();
 402                         rip_query();
 403                         continue;
 404                 }
 405
 406                 /* Check the kernel table occassionally for mysteriously
 407                  * evaporated routes
 408                  */
 409                 timevalsub(&t2, &flush_kern_timer, &now);
 410                 if (t2.tv_sec <= 0) {
 411                         flush_kern();
 412                         flush_kern_timer.tv_sec = (now.tv_sec
 413                                                    + CHECK_QUIET_INTERVAL);
 414                         continue;
 415                 }
 416                 if (timercmp(&t2, &wtime, <))
 417                         wtime = t2;
 418
 419                 /* If it is time, then broadcast our routes.
 420                  */
 421                 if (supplier || advertise_mhome) {
 422                         timevalsub(&t2, &next_bcast, &now);
 423                         if (t2.tv_sec <= 0) {
 424                                 /* Synchronize the aging and broadcast
 425                                  * timers to minimize awakenings
 426                                  */
 427                                 age(0);
 428
 429                                 rip_bcast(0);
 430
 431                                 /* It is desirable to send routing updates
 432                                  * regularly.  So schedule the next update
 433                                  * 30 seconds after the previous one was
 434                                  * scheduled, instead of 30 seconds after
 435                                  * the previous update was finished.
 436                                  * Even if we just started after discovering
 437                                  * a 2nd interface or were otherwise delayed,
 438                                  * pick a 30-second aniversary of the
 439                                  * original broadcast time.
 440                                  */
 441                                 n = 1 + (0-t2.tv_sec)/SUPPLY_INTERVAL;
 442                                 next_bcast.tv_sec += n*SUPPLY_INTERVAL;
 443
 444                                 continue;
 445                         }
 446
 447                         if (timercmp(&t2, &wtime, <))
 448                                 wtime = t2;
 449                 }
 450
 451                 /* If we need a flash update, either do it now or
 452                  * set the delay to end when it is time.
 453                  *
 454                  * If we are within MIN_WAITTIME seconds of a full update,
 455                  * do not bother.
 456                  */
 457                 if (need_flash
 458                     && supplier
 459                     && no_flash.tv_sec+MIN_WAITTIME < next_bcast.tv_sec) {
 460                         /* accurate to the millisecond */
 461                         if (!timercmp(&no_flash, &now, >))
 462                                 rip_bcast(1);
 463                         timevalsub(&t2, &no_flash, &now);
 464                         if (timercmp(&t2, &wtime, <))
 465                                 wtime = t2;
 466                 }
 467
 468                 /* trigger the main aging timer.
 469                  */
 470                 timevalsub(&t2, &age_timer, &now);
 471                 if (t2.tv_sec <= 0) {
 472                         age(0);
 473                         continue;
 474                 }
 475                 if (timercmp(&t2, &wtime, <))
 476                         wtime = t2;
 477
 478                 /* update the kernel routing table
 479                  */
 480                 timevalsub(&t2, &need_kern, &now);
 481                 if (t2.tv_sec <= 0) {
 482                         age(0);
 483                         continue;
 484                 }
 485                 if (timercmp(&t2, &wtime, <))
 486                         wtime = t2;
 487
 488                 /* take care of router discovery,
 489                  * but do it in the correct the millisecond
 490                  */
 491                 if (!timercmp(&rdisc_timer, &now, >)) {
 492                         rdisc_age(0);
 493                         continue;
 494                 }
 495                 timevalsub(&t2, &rdisc_timer, &now);
 496                 if (timercmp(&t2, &wtime, <))
 497                         wtime = t2;
 498
 499
 500                 /* wait for input or a timer to expire.
 501                  */
 502                 trace_flush();
 503                 ibits = fdbits;
 504                 n = select(sock_max, &ibits, 0, 0, &wtime);
 505                 if (n <= 0) {
 506                         if (n < 0 && errno != EINTR && errno != EAGAIN)
 507                                 BADERR(1,"select");
 508                         continue;
 509                 }
 510
 511                 if (FD_ISSET(rt_sock, &ibits)) {
 512                         read_rt();
 513                         n--;
 514                 }
 515                 if (rdisc_sock >= 0 && FD_ISSET(rdisc_sock, &ibits)) {
 516                         read_d();
 517                         n--;
 518                 }
 519                 if (rip_sock >= 0 && FD_ISSET(rip_sock, &ibits)) {
 520                         read_rip(rip_sock, 0);
 521                         n--;
 522                 }
 523
 524                 for (ifp = ifnet; n > 0 && 0 != ifp; ifp = ifp->int_next) {
 525                         if (ifp->int_rip_sock >= 0
 526                             && FD_ISSET(ifp->int_rip_sock, &ibits)) {
 527                                 read_rip(ifp->int_rip_sock, ifp);
 528                                 n--;
 529                         }
 530                 }
 531         }
 532 }
 533
 534
 535 /* ARGSUSED */
 536 void
 537 sigalrm(int s UNUSED)
 538 {
 539         /* Historically, SIGALRM would cause the daemon to check for
 540          * new and broken interfaces.
 541          */
 542         ifinit_timer.tv_sec = now.tv_sec;
 543         trace_act("SIGALRM");
 544 }
 545
 546
 547 /* watch for fatal signals */
 548 void
 549 sigterm(int sig)
 550 {
 551         stopint = sig;
 552         signal(sig, SIG_DFL);   /* catch it only once */
 553 }
 554
 555
 556 void
 557 fix_select(void)
 558 {
 559         struct interface *ifp;
 560
 561
 562         FD_ZERO(&fdbits);
 563         sock_max = 0;
 564
 565         FD_SET(rt_sock, &fdbits);
 566         if (sock_max <= rt_sock)
 567                 sock_max = rt_sock+1;
 568         if (rip_sock >= 0) {
 569                 FD_SET(rip_sock, &fdbits);
 570                 if (sock_max <= rip_sock)
 571                         sock_max = rip_sock+1;
 572         }
 573         for (ifp = ifnet; NULL != ifp; ifp = ifp->int_next) {
 574                 if (ifp->int_rip_sock >= 0) {
 575                         FD_SET(ifp->int_rip_sock, &fdbits);
 576                         if (sock_max <= ifp->int_rip_sock)
 577                                 sock_max = ifp->int_rip_sock+1;
 578                 }
 579         }
 580         if (rdisc_sock >= 0) {
 581                 FD_SET(rdisc_sock, &fdbits);
 582                 if (sock_max <= rdisc_sock)
 583                         sock_max = rdisc_sock+1;
 584         }
 585 }
 586
 587
 588 void
 589 fix_sock(int sock,
 590          const char *name)
 591 {
 592         int on;
 593 #define MIN_SOCKBUF (4*1024)
 594         static int rbuf;
 595
 596         if (fcntl(sock, F_SETFL, O_NONBLOCK) == -1)
 597                 logbad(1, "fcntl(%s) O_NONBLOCK: %s",
 598                        name, strerror(errno));
 599         on = 1;
 600         if (setsockopt(sock, SOL_SOCKET,SO_BROADCAST, &on,sizeof(on)) < 0)
 601                 msglog("setsockopt(%s,SO_BROADCAST): %s",
 602                        name, strerror(errno));
 603 #ifdef USE_PASSIFNAME
 604         on = 1;
 605         if (setsockopt(sock, SOL_SOCKET, SO_PASSIFNAME, &on,sizeof(on)) < 0)
 606                 msglog("setsockopt(%s,SO_PASSIFNAME): %s",
 607                        name, strerror(errno));
 608 #endif
 609
 610         if (rbuf >= MIN_SOCKBUF) {
 611                 if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
 612                                &rbuf, sizeof(rbuf)) < 0)
 613                         msglog("setsockopt(%s,SO_RCVBUF=%d): %s",
 614                                name, rbuf, strerror(errno));
 615         } else {
 616                 for (rbuf = 60*1024; ; rbuf -= 4096) {
 617                         if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
 618                                        &rbuf, sizeof(rbuf)) == 0) {
 619                                 trace_act("RCVBUF=%d", rbuf);
 620                                 break;
 621                         }
 622                         if (rbuf < MIN_SOCKBUF) {
 623                                 msglog("setsockopt(%s,SO_RCVBUF = %d): %s",
 624                                        name, rbuf, strerror(errno));
 625                                 break;
 626                         }
 627                 }
 628         }
 629 }
 630
 631
 632 /* get a rip socket
 633  */
 634 static int                              /* <0 or file descriptor */
 635 get_rip_sock(naddr addr,
 636              int serious)               /* 1=failure to bind is serious */
 637 {
 638         struct sockaddr_in in;
 639         unsigned char ttl;
 640         int s;
 641
 642
 643         if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
 644                 BADERR(1,"rip_sock = socket()");
 645
 646         memset(&in, 0, sizeof(in));
 647 #ifdef _HAVE_SIN_LEN
 648         in.sin_len = sizeof(in);
 649 #endif
 650         in.sin_family = AF_INET;
 651         in.sin_port = htons(RIP_PORT);
 652         in.sin_addr.s_addr = addr;
 653         if (bind(s, (struct sockaddr *)&in, sizeof(in)) < 0) {
 654                 if (serious)
 655                         BADERR(errno != EADDRINUSE, "bind(rip_sock)");
 656                 return -1;
 657         }
 658         fix_sock(s,"rip_sock");
 659
 660         ttl = 1;
 661         if (setsockopt(s, IPPROTO_IP, IP_MULTICAST_TTL,
 662                        &ttl, sizeof(ttl)) < 0)
 663                 DBGERR(1,"rip_sock setsockopt(IP_MULTICAST_TTL)");
 664
 665         return s;
 666 }
 667
 668
 669 /* turn off main RIP socket */
 670 void
 671 rip_off(void)
 672 {
 673         struct interface *ifp;
 674         naddr addr;
 675
 676
 677         if (rip_sock >= 0 && !mhome) {
 678                 trace_act("turn off RIP");
 679
 680                 close(rip_sock);
 681                 rip_sock = -1;
 682
 683                 /* get non-broadcast sockets to listen to queries.
 684                  */
 685                 for (ifp = ifnet; ifp != NULL; ifp = ifp->int_next) {
 686                         if (ifp->int_state & IS_REMOTE)
 687                                 continue;
 688                         if (ifp->int_rip_sock < 0) {
 689                                 addr = ((ifp->int_if_flags & IFF_POINTOPOINT)
 690                                         ? ifp->int_dstaddr
 691                                         : ifp->int_addr);
 692                                 ifp->int_rip_sock = get_rip_sock(addr, 0);
 693                         }
 694                 }
 695
 696                 fix_select();
 697
 698                 age(0);
 699         }
 700 }
 701
 702
 703 /* turn on RIP multicast input via an interface
 704  */
 705 static void
 706 rip_mcast_on(struct interface *ifp)
 707 {
 708         struct ip_mreq m;
 709
 710         if (!IS_RIP_IN_OFF(ifp->int_state)
 711             && (ifp->int_if_flags & IFF_MULTICAST)
 712 #ifdef MCAST_PPP_BUG
 713             && !(ifp->int_if_flags & IFF_POINTOPOINT)
 714 #endif
 715             && !(ifp->int_state & IS_ALIAS)) {
 716                 m.imr_multiaddr.s_addr = htonl(INADDR_RIP_GROUP);
 717                 m.imr_interface.s_addr = ((ifp->int_if_flags & IFF_POINTOPOINT)
 718                                           ? ifp->int_dstaddr
 719                                           : ifp->int_addr);
 720                 if (setsockopt(rip_sock,IPPROTO_IP, IP_ADD_MEMBERSHIP,
 721                                &m, sizeof(m)) < 0)
 722                         LOGERR("setsockopt(IP_ADD_MEMBERSHIP RIP)");
 723         }
 724 }
 725
 726
 727 /* Prepare socket used for RIP.
 728  */
 729 void
 730 rip_on(struct interface *ifp)
 731 {
 732         /* If the main RIP socket is already alive, only start receiving
 733          * multicasts for this interface.
 734          */
 735         if (rip_sock >= 0) {
 736                 if (ifp != NULL)
 737                         rip_mcast_on(ifp);
 738                 return;
 739         }
 740
 741         /* If the main RIP socket is off and it makes sense to turn it on,
 742          * then turn it on for all of the interfaces.
 743          * It makes sense if either router discovery is off, or if
 744          * router discover is on and at most one interface is doing RIP.
 745          */
 746         if (rip_interfaces > 0 && (!rdisc_ok || rip_interfaces > 1)) {
 747                 trace_act("turn on RIP");
 748
 749                 /* Close all of the query sockets so that we can open
 750                  * the main socket.  SO_REUSEPORT is not a solution,
 751                  * since that would let two daemons bind to the broadcast
 752                  * socket.
 753                  */
 754                 for (ifp = ifnet; ifp != NULL; ifp = ifp->int_next) {
 755                         if (ifp->int_rip_sock >= 0) {
 756                                 close(ifp->int_rip_sock);
 757                                 ifp->int_rip_sock = -1;
 758                         }
 759                 }
 760
 761                 rip_sock = get_rip_sock(INADDR_ANY, 1);
 762                 rip_sock_mcast = NULL;
 763
 764                 /* Do not advertise anything until we have heard something
 765                  */
 766                 if (next_bcast.tv_sec < now.tv_sec+MIN_WAITTIME)
 767                         next_bcast.tv_sec = now.tv_sec+MIN_WAITTIME;
 768
 769                 for (ifp = ifnet; ifp != NULL; ifp = ifp->int_next) {
 770                         ifp->int_query_time = NEVER;
 771                         rip_mcast_on(ifp);
 772                 }
 773                 ifinit_timer.tv_sec = now.tv_sec;
 774
 775         } else if (ifp != NULL
 776                    && !(ifp->int_state & IS_REMOTE)
 777                    && ifp->int_rip_sock < 0) {
 778                 /* RIP is off, so ensure there are sockets on which
 779                  * to listen for queries.
 780                  */
 781                 ifp->int_rip_sock = get_rip_sock(ifp->int_addr, 0);
 782         }
 783
 784         fix_select();
 785 }
 786
 787
 788 /* die if malloc(3) fails
 789  */
 790 void *
 791 rtmalloc(size_t size,
 792          const char *msg)
 793 {
 794         void *p = malloc(size);
 795         if (p == NULL)
 796                 logbad(1,"malloc(%lu) failed in %s", (u_long)size, msg);
 797         return p;
 798 }
 799
 800
 801 /* get a random instant in an interval
 802  */
 803 void
 804 intvl_random(struct timeval *tp,        /* put value here */
 805              u_long lo,                 /* value is after this second */
 806              u_long hi)                 /* and before this */
 807 {
 808         tp->tv_sec = (time_t)(hi == lo
 809                               ? lo
 810                               : (lo + random() % ((hi - lo))));
 811         tp->tv_usec = random() % 1000000;
 812 }
 813
 814
 815 void
 816 timevaladd(struct timeval *t1,
 817            struct timeval *t2)
 818 {
 819
 820         t1->tv_sec += t2->tv_sec;
 821         if ((t1->tv_usec += t2->tv_usec) >= 1000000) {
 822                 t1->tv_sec++;
 823                 t1->tv_usec -= 1000000;
 824         }
 825 }
 826
 827
 828 /* t1 = t2 - t3
 829  */
 830 static void
 831 timevalsub(struct timeval *t1,
 832            struct timeval *t2,
 833            struct timeval *t3)
 834 {
 835         t1->tv_sec = t2->tv_sec - t3->tv_sec;
 836         if ((t1->tv_usec = t2->tv_usec - t3->tv_usec) < 0) {
 837                 t1->tv_sec--;
 838                 t1->tv_usec += 1000000;
 839         }
 840 }
 841
 842
 843 /* put a message into the system log
 844  */
 845 void
 846 msglog(const char *p, ...)
 847 {
 848         va_list args;
 849
 850         trace_flush();
 851
 852         va_start(args, p);
 853         vsyslog(LOG_ERR, p, args);
 854
 855         if (ftrace != 0) {
 856                 if (ftrace == stdout)
 857                         fputs("routed: ", ftrace);
 858                 vfprintf(ftrace, p, args);
 859                 fputc('\n', ftrace);
 860         }
 861 }
 862
 863
 864 /* Put a message about a bad system into the system log if
 865  * we have not complained about it recently.
 866  *
 867  * It is desirable to complain about all bad systems, but not too often.
 868  * In the worst case, it is not practical to keep track of all bad systems.
 869  * For example, there can be many systems with the wrong password.
 870  */
 871 void
 872 msglim(struct msg_limit *lim, naddr addr, const char *p, ...)
 873 {
 874         va_list args;
 875         int i;
 876         struct msg_sub *ms1, *ms;
 877         const char *p1;
 878
 879         va_start(args, p);
 880
 881         /* look for the oldest slot in the table
 882          * or the slot for the bad router.
 883          */
 884         ms = ms1 = lim->subs;
 885         for (i = MSG_SUBJECT_N; ; i--, ms1++) {
 886                 if (i == 0) {
 887                         /* Reuse a slot at most once every 10 minutes.
 888                          */
 889                         if (lim->reuse > now.tv_sec) {
 890                                 ms = NULL;
 891                         } else {
 892                                 ms = ms1;
 893                                 lim->reuse = now.tv_sec + 10*60;
 894                         }
 895                         break;
 896                 }
 897                 if (ms->addr == addr) {
 898                         /* Repeat a complaint about a given system at
 899                          * most once an hour.
 900                          */
 901                         if (ms->until > now.tv_sec)
 902                                 ms = NULL;
 903                         break;
 904                 }
 905                 if (ms->until < ms1->until)
 906                         ms = ms1;
 907         }
 908         if (ms != NULL) {
 909                 ms->addr = addr;
 910                 ms->until = now.tv_sec + 60*60; /* 60 minutes */
 911
 912                 trace_flush();
 913                 for (p1 = p; *p1 == ' '; p1++)
 914                         continue;
 915                 vsyslog(LOG_ERR, p1, args);
 916         }
 917
 918         /* always display the message if tracing */
 919         if (ftrace != 0) {
 920                 vfprintf(ftrace, p, args);
 921                 fputc('\n', ftrace);
 922         }
 923 }
 924
 925
 926 void
 927 logbad(int dump, const char *p, ...)
 928 {
 929         va_list args;
 930
 931         trace_flush();
 932
 933         va_start(args, p);
 934         vsyslog(LOG_ERR, p, args);
 935
 936         fputs("routed: ", stderr);
 937         vfprintf(stderr, p, args);
 938         fputs("; giving up\n",stderr);
 939         fflush(stderr);
 940
 941         if (dump)
 942                 abort();
 943         exit(1);
 944 }