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  * 4. 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  * $FreeBSD$
  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 __COPYRIGHT("@(#) Copyright (c) 1983, 1988, 1993 "
  42             "The Regents of the University of California."
  43             "  All rights reserved.");
  44 #ifdef __NetBSD__
  45 __RCSID("$NetBSD$");
  46 #include <util.h>
  47 #elif defined(__FreeBSD__)
  48 __RCSID("$FreeBSD$");
  49 #else
  50 __RCSID("$Revision: 2.31 $");
  51 #ident "$Revision: 2.31 $"
  52 #endif
  53
  54 pid_t   mypid;
  55
  56 naddr   myaddr;                         /* system address */
  57 static char myname[MAXHOSTNAMELEN+1];
  58
  59 static int verbose;
  60
  61 int     supplier;                       /* supply or broadcast updates */
  62 int     supplier_set;
  63 static int ipforwarding = 1;            /* kernel forwarding on */
  64
  65 static int default_gateway;             /* 1=advertise default */
  66 static int background = 1;
  67 int     ridhosts;                       /* 1=reduce host routes */
  68 int     mhome;                          /* 1=want multi-homed host route */
  69 int     advertise_mhome;                /* 1=must continue advertising it */
  70 int     auth_ok = 1;                    /* 1=ignore auth if we do not care */
  71 int     insecure;                       /* Reply to special queries or not */
  72
  73 struct timeval epoch;                   /* when started */
  74 struct timeval clk;
  75 static struct timeval prev_clk;
  76 static int usec_fudge;
  77 struct timeval now;                     /* current idea of time */
  78 time_t  now_stale;
  79 time_t  now_expire;
  80 time_t  now_garbage;
  81
  82 static struct timeval next_bcast;       /* next general broadcast */
  83 struct timeval no_flash = {             /* inhibit flash update */
  84         EPOCH+SUPPLY_INTERVAL, 0
  85 };
  86
  87 static struct timeval flush_kern_timer;
  88
  89 static fd_set fdbits;
  90 static int sock_max;
  91 int     rip_sock = -1;                  /* RIP socket */
  92 const struct interface *rip_sock_mcast; /* current multicast interface */
  93 int     rt_sock;                        /* routing socket */
  94 int     rt_sock_seqno;
  95
  96
  97 static  int get_rip_sock(naddr, int);
  98 static void timevalsub(struct timeval *, struct timeval *, struct timeval *);
  99 static void sigalrm(int s UNUSED);
 100 static void sigterm(int sig);
 101
 102 int
 103 main(int argc,
 104      char *argv[])
 105 {
 106         int n, mib[4], off;
 107         size_t len;
 108         char *p, *q;
 109         const char *cp;
 110         struct timeval wtime, t2;
 111         time_t dt;
 112         fd_set ibits;
 113         naddr p_net, p_mask;
 114         struct interface *ifp;
 115         struct parm parm;
 116         char *tracename = 0;
 117
 118
 119         /* Some shells are badly broken and send SIGHUP to backgrounded
 120          * processes.
 121          */
 122         signal(SIGHUP, SIG_IGN);
 123
 124         openlog("routed", LOG_PID, LOG_DAEMON);
 125         ftrace = stdout;
 126
 127         gettimeofday(&clk, 0);
 128         prev_clk = clk;
 129         epoch = clk;
 130         epoch.tv_sec -= EPOCH;
 131         now.tv_sec = EPOCH;
 132         now_stale = EPOCH - STALE_TIME;
 133         now_expire = EPOCH - EXPIRE_TIME;
 134         now_garbage = EPOCH - GARBAGE_TIME;
 135         wtime.tv_sec = 0;
 136
 137         (void)gethostname(myname, sizeof(myname)-1);
 138         (void)gethost(myname, &myaddr);
 139
 140         while ((n = getopt(argc, argv, "isqdghmAtvT:F:P:")) != -1) {
 141                 switch (n) {
 142                 case 'i':
 143                         insecure++;
 144                         break;
 145                 case 's':
 146                         supplier = 1;
 147                         supplier_set = 1;
 148                         break;
 149
 150                 case 'q':
 151                         supplier = 0;
 152                         supplier_set = 1;
 153                         break;
 154
 155                 case 'd':
 156                         background = 0;
 157                         break;
 158
 159                 case 'g':
 160                         memset(&parm, 0, sizeof(parm));
 161                         parm.parm_d_metric = 1;
 162                         cp = check_parms(&parm);
 163                         if (cp != 0)
 164                                 msglog("bad -g: %s", cp);
 165                         else
 166                                 default_gateway = 1;
 167                         break;
 168
 169                 case 'h':               /* suppress extra host routes */
 170                         ridhosts = 1;
 171                         break;
 172
 173                 case 'm':               /* advertise host route */
 174                         mhome = 1;      /* on multi-homed hosts */
 175                         break;
 176
 177                 case 'A':
 178                         /* Ignore authentication if we do not care.
 179                          * Crazy as it is, that is what RFC 1723 requires.
 180                          */
 181                         auth_ok = 0;
 182                         break;
 183
 184                 case 't':
 185                         new_tracelevel++;
 186                         break;
 187
 188                 case 'T':
 189                         tracename = optarg;
 190                         break;
 191
 192                 case 'F':               /* minimal routes for SLIP */
 193                         n = FAKE_METRIC;
 194                         p = strchr(optarg,',');
 195                         if (p && *p != '\0') {
 196                                 n = (int)strtoul(p+1, &q, 0);
 197                                 if (*q == '\0'
 198                                     && n <= HOPCNT_INFINITY-1
 199                                     && n >= 1)
 200                                         *p = '\0';
 201                         }
 202                         if (!getnet(optarg, &p_net, &p_mask)) {
 203                                 msglog("bad network; \"-F %s\"",
 204                                        optarg);
 205                                 break;
 206                         }
 207                         memset(&parm, 0, sizeof(parm));
 208                         parm.parm_net = p_net;
 209                         parm.parm_mask = p_mask;
 210                         parm.parm_d_metric = n;
 211                         cp = check_parms(&parm);
 212                         if (cp != 0)
 213                                 msglog("bad -F: %s", cp);
 214                         break;
 215
 216                 case 'P':
 217                         /* handle arbitrary parameters.
 218                          */
 219                         q = strdup(optarg);
 220                         cp = parse_parms(q, 0);
 221                         if (cp != 0)
 222                                 msglog("%s in \"-P %s\"", cp, optarg);
 223                         free(q);
 224                         break;
 225
 226                 case 'v':
 227                         /* display version */
 228                         verbose++;
 229                         msglog("version 2.31");
 230                         break;
 231
 232                 default:
 233                         goto usage;
 234                 }
 235         }
 236         argc -= optind;
 237         argv += optind;
 238
 239         if (tracename == 0 && argc >= 1) {
 240                 tracename = *argv++;
 241                 argc--;
 242         }
 243         if (tracename != 0 && tracename[0] == '\0')
 244                 goto usage;
 245         if (argc != 0) {
 246 usage:
 247                 logbad(0, "usage: routed [-sqdghmAtv] [-T tracefile]"
 248                        " [-F net[,metric]] [-P parms]");
 249         }
 250         if (geteuid() != 0) {
 251                 if (verbose)
 252                         exit(0);
 253                 logbad(0, "requires UID 0");
 254         }
 255
 256         mib[0] = CTL_NET;
 257         mib[1] = PF_INET;
 258         mib[2] = IPPROTO_IP;
 259         mib[3] = IPCTL_FORWARDING;
 260         len = sizeof(ipforwarding);
 261         if (sysctl(mib, 4, &ipforwarding, &len, 0, 0) < 0)
 262                 LOGERR("sysctl(IPCTL_FORWARDING)");
 263
 264         if (!ipforwarding) {
 265                 if (supplier)
 266                         msglog("-s incompatible with ipforwarding=0");
 267                 if (default_gateway) {
 268                         msglog("-g incompatible with ipforwarding=0");
 269                         default_gateway = 0;
 270                 }
 271                 supplier = 0;
 272                 supplier_set = 1;
 273         }
 274         if (default_gateway) {
 275                 if (supplier_set && !supplier) {
 276                         msglog("-g and -q incompatible");
 277                 } else {
 278                         supplier = 1;
 279                         supplier_set = 1;
 280                 }
 281         }
 282
 283
 284         signal(SIGALRM, sigalrm);
 285         if (!background)
 286                 signal(SIGHUP, sigterm);    /* SIGHUP fatal during debugging */
 287         signal(SIGTERM, sigterm);
 288         signal(SIGINT, sigterm);
 289         signal(SIGUSR1, sigtrace_on);
 290         signal(SIGUSR2, sigtrace_off);
 291
 292         /* get into the background */
 293 #ifdef sgi
 294         if (0 > _daemonize(background ? 0 : (_DF_NOCHDIR|_DF_NOFORK),
 295                            STDIN_FILENO, STDOUT_FILENO, STDERR_FILENO))
 296                 BADERR(0, "_daemonize()");
 297 #else
 298         if (background && daemon(0, 1) < 0)
 299                 BADERR(0,"daemon()");
 300 #endif
 301
 302 #if defined(__NetBSD__)
 303         pidfile(0);
 304 #endif
 305         mypid = getpid();
 306
 307         /* prepare socket connected to the kernel.
 308          */
 309         rt_sock = socket(AF_ROUTE, SOCK_RAW, 0);
 310         if (rt_sock < 0)
 311                 BADERR(1,"rt_sock = socket()");
 312         if (fcntl(rt_sock, F_SETFL, O_NONBLOCK) == -1)
 313                 logbad(1, "fcntl(rt_sock) O_NONBLOCK: %s", strerror(errno));
 314         off = 0;
 315         if (setsockopt(rt_sock, SOL_SOCKET,SO_USELOOPBACK,
 316                        &off,sizeof(off)) < 0)
 317                 LOGERR("setsockopt(SO_USELOOPBACK,0)");
 318
 319         fix_select();
 320
 321
 322         if (tracename != 0) {
 323                 strncpy(inittracename, tracename, sizeof(inittracename)-1);
 324                 set_tracefile(inittracename, "%s", -1);
 325         } else {
 326                 tracelevel_msg("%s", -1);   /* turn on tracing to stdio */
 327         }
 328
 329         bufinit();
 330
 331         /* initialize radix tree */
 332         rtinit();
 333
 334         /* Pick a random part of the second for our output to minimize
 335          * collisions.
 336          *
 337          * Start broadcasting after hearing from other routers, and
 338          * at a random time so a bunch of systems do not get synchronized
 339          * after a power failure.
 340          */
 341         intvl_random(&next_bcast, EPOCH+MIN_WAITTIME, EPOCH+SUPPLY_INTERVAL);
 342         age_timer.tv_usec = next_bcast.tv_usec;
 343         age_timer.tv_sec = EPOCH+MIN_WAITTIME;
 344         rdisc_timer = next_bcast;
 345         ifinit_timer.tv_usec = next_bcast.tv_usec;
 346
 347         /* Collect an initial view of the world by checking the interface
 348          * configuration and the kludge file.
 349          */
 350         gwkludge();
 351         ifinit();
 352
 353         /* Ask for routes */
 354         rip_query();
 355         rdisc_sol();
 356
 357         /* Now turn off stdio if not tracing */
 358         if (new_tracelevel == 0)
 359                 trace_close(background);
 360
 361         /* Loop forever, listening and broadcasting.
 362          */
 363         for (;;) {
 364                 prev_clk = clk;
 365                 gettimeofday(&clk, 0);
 366                 if (prev_clk.tv_sec == clk.tv_sec
 367                     && prev_clk.tv_usec == clk.tv_usec+usec_fudge) {
 368                         /* Much of `routed` depends on time always advancing.
 369                          * On systems that do not guarantee that gettimeofday()
 370                          * produces unique timestamps even if called within
 371                          * a single tick, use trickery like that in classic
 372                          * BSD kernels.
 373                          */
 374                         clk.tv_usec += ++usec_fudge;
 375
 376                 } else {
 377                         usec_fudge = 0;
 378
 379                         timevalsub(&t2, &clk, &prev_clk);
 380                         if (t2.tv_sec < 0
 381                             || t2.tv_sec > wtime.tv_sec + 5) {
 382                                 /* Deal with time changes before other
 383                                  * housekeeping to keep everything straight.
 384                                  */
 385                                 dt = t2.tv_sec;
 386                                 if (dt > 0)
 387                                         dt -= wtime.tv_sec;
 388                                 trace_act("time changed by %d sec", (int)dt);
 389                                 epoch.tv_sec += dt;
 390                         }
 391                 }
 392                 timevalsub(&now, &clk, &epoch);
 393                 now_stale = now.tv_sec - STALE_TIME;
 394                 now_expire = now.tv_sec - EXPIRE_TIME;
 395                 now_garbage = now.tv_sec - GARBAGE_TIME;
 396
 397                 /* deal with signals that should affect tracing */
 398                 set_tracelevel();
 399
 400                 if (stopint != 0) {
 401                         rip_bcast(0);
 402                         rdisc_adv();
 403                         trace_off("exiting with signal %d", stopint);
 404                         exit(stopint | 128);
 405                 }
 406
 407                 /* look for new or dead interfaces */
 408                 timevalsub(&wtime, &ifinit_timer, &now);
 409                 if (wtime.tv_sec <= 0) {
 410                         wtime.tv_sec = 0;
 411                         ifinit();
 412                         rip_query();
 413                         continue;
 414                 }
 415
 416                 /* Check the kernel table occasionally for mysteriously
 417                  * evaporated routes
 418                  */
 419                 timevalsub(&t2, &flush_kern_timer, &now);
 420                 if (t2.tv_sec <= 0) {
 421                         flush_kern();
 422                         flush_kern_timer.tv_sec = (now.tv_sec
 423                                                    + CHECK_QUIET_INTERVAL);
 424                         continue;
 425                 }
 426                 if (timercmp(&t2, &wtime, <))
 427                         wtime = t2;
 428
 429                 /* If it is time, then broadcast our routes.
 430                  */
 431                 if (supplier || advertise_mhome) {
 432                         timevalsub(&t2, &next_bcast, &now);
 433                         if (t2.tv_sec <= 0) {
 434                                 /* Synchronize the aging and broadcast
 435                                  * timers to minimize awakenings
 436                                  */
 437                                 age(0);
 438
 439                                 rip_bcast(0);
 440
 441                                 /* It is desirable to send routing updates
 442                                  * regularly.  So schedule the next update
 443                                  * 30 seconds after the previous one was
 444                                  * scheduled, instead of 30 seconds after
 445                                  * the previous update was finished.
 446                                  * Even if we just started after discovering
 447                                  * a 2nd interface or were otherwise delayed,
 448                                  * pick a 30-second anniversary of the
 449                                  * original broadcast time.
 450                                  */
 451                                 n = 1 + (0-t2.tv_sec)/SUPPLY_INTERVAL;
 452                                 next_bcast.tv_sec += n*SUPPLY_INTERVAL;
 453
 454                                 continue;
 455                         }
 456
 457                         if (timercmp(&t2, &wtime, <))
 458                                 wtime = t2;
 459                 }
 460
 461                 /* If we need a flash update, either do it now or
 462                  * set the delay to end when it is time.
 463                  *
 464                  * If we are within MIN_WAITTIME seconds of a full update,
 465                  * do not bother.
 466                  */
 467                 if (need_flash
 468                     && supplier
 469                     && no_flash.tv_sec+MIN_WAITTIME < next_bcast.tv_sec) {
 470                         /* accurate to the millisecond */
 471                         if (!timercmp(&no_flash, &now, >))
 472                                 rip_bcast(1);
 473                         timevalsub(&t2, &no_flash, &now);
 474                         if (timercmp(&t2, &wtime, <))
 475                                 wtime = t2;
 476                 }
 477
 478                 /* trigger the main aging timer.
 479                  */
 480                 timevalsub(&t2, &age_timer, &now);
 481                 if (t2.tv_sec <= 0) {
 482                         age(0);
 483                         continue;
 484                 }
 485                 if (timercmp(&t2, &wtime, <))
 486                         wtime = t2;
 487
 488                 /* update the kernel routing table
 489                  */
 490                 timevalsub(&t2, &need_kern, &now);
 491                 if (t2.tv_sec <= 0) {
 492                         age(0);
 493                         continue;
 494                 }
 495                 if (timercmp(&t2, &wtime, <))
 496                         wtime = t2;
 497
 498                 /* take care of router discovery,
 499                  * but do it in the correct the millisecond
 500                  */
 501                 if (!timercmp(&rdisc_timer, &now, >)) {
 502                         rdisc_age(0);
 503                         continue;
 504                 }
 505                 timevalsub(&t2, &rdisc_timer, &now);
 506                 if (timercmp(&t2, &wtime, <))
 507                         wtime = t2;
 508
 509
 510                 /* wait for input or a timer to expire.
 511                  */
 512                 trace_flush();
 513                 ibits = fdbits;
 514                 n = select(sock_max, &ibits, 0, 0, &wtime);
 515                 if (n <= 0) {
 516                         if (n < 0 && errno != EINTR && errno != EAGAIN)
 517                                 BADERR(1,"select");
 518                         continue;
 519                 }
 520
 521                 if (FD_ISSET(rt_sock, &ibits)) {
 522                         read_rt();
 523                         n--;
 524                 }
 525                 if (rdisc_sock >= 0 && FD_ISSET(rdisc_sock, &ibits)) {
 526                         read_d();
 527                         n--;
 528                 }
 529                 if (rip_sock >= 0 && FD_ISSET(rip_sock, &ibits)) {
 530                         read_rip(rip_sock, 0);
 531                         n--;
 532                 }
 533
 534                 LIST_FOREACH(ifp, &ifnet, int_list) {
 535                         if (n <= 0)
 536                                 break;
 537                         if (ifp->int_rip_sock >= 0
 538                             && FD_ISSET(ifp->int_rip_sock, &ibits)) {
 539                                 read_rip(ifp->int_rip_sock, ifp);
 540                                 n--;
 541                         }
 542                 }
 543         }
 544 }
 545
 546
 547 /* ARGSUSED */
 548 static void
 549 sigalrm(int s UNUSED)
 550 {
 551         /* Historically, SIGALRM would cause the daemon to check for
 552          * new and broken interfaces.
 553          */
 554         ifinit_timer.tv_sec = now.tv_sec;
 555         trace_act("SIGALRM");
 556 }
 557
 558
 559 /* watch for fatal signals */
 560 static void
 561 sigterm(int sig)
 562 {
 563         stopint = sig;
 564         (void)signal(sig, SIG_DFL);     /* catch it only once */
 565 }
 566
 567
 568 void
 569 fix_select(void)
 570 {
 571         struct interface *ifp;
 572
 573
 574         FD_ZERO(&fdbits);
 575         sock_max = 0;
 576
 577         FD_SET(rt_sock, &fdbits);
 578         if (sock_max <= rt_sock)
 579                 sock_max = rt_sock+1;
 580         if (rip_sock >= 0) {
 581                 FD_SET(rip_sock, &fdbits);
 582                 if (sock_max <= rip_sock)
 583                         sock_max = rip_sock+1;
 584         }
 585         LIST_FOREACH(ifp, &ifnet, int_list) {
 586                 if (ifp->int_rip_sock >= 0) {
 587                         FD_SET(ifp->int_rip_sock, &fdbits);
 588                         if (sock_max <= ifp->int_rip_sock)
 589                                 sock_max = ifp->int_rip_sock+1;
 590                 }
 591         }
 592         if (rdisc_sock >= 0) {
 593                 FD_SET(rdisc_sock, &fdbits);
 594                 if (sock_max <= rdisc_sock)
 595                         sock_max = rdisc_sock+1;
 596         }
 597 }
 598
 599
 600 void
 601 fix_sock(int sock,
 602          const char *name)
 603 {
 604         int on;
 605 #define MIN_SOCKBUF (4*1024)
 606         static int rbuf;
 607
 608         if (fcntl(sock, F_SETFL, O_NONBLOCK) == -1)
 609                 logbad(1, "fcntl(%s) O_NONBLOCK: %s",
 610                        name, strerror(errno));
 611         on = 1;
 612         if (setsockopt(sock, SOL_SOCKET,SO_BROADCAST, &on,sizeof(on)) < 0)
 613                 msglog("setsockopt(%s,SO_BROADCAST): %s",
 614                        name, strerror(errno));
 615 #ifdef USE_PASSIFNAME
 616         on = 1;
 617         if (setsockopt(sock, SOL_SOCKET, SO_PASSIFNAME, &on,sizeof(on)) < 0)
 618                 msglog("setsockopt(%s,SO_PASSIFNAME): %s",
 619                        name, strerror(errno));
 620 #endif
 621
 622         if (rbuf >= MIN_SOCKBUF) {
 623                 if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
 624                                &rbuf, sizeof(rbuf)) < 0)
 625                         msglog("setsockopt(%s,SO_RCVBUF=%d): %s",
 626                                name, rbuf, strerror(errno));
 627         } else {
 628                 for (rbuf = 60*1024; ; rbuf -= 4096) {
 629                         if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
 630                                        &rbuf, sizeof(rbuf)) == 0) {
 631                                 trace_act("RCVBUF=%d", rbuf);
 632                                 break;
 633                         }
 634                         if (rbuf < MIN_SOCKBUF) {
 635                                 msglog("setsockopt(%s,SO_RCVBUF = %d): %s",
 636                                        name, rbuf, strerror(errno));
 637                                 break;
 638                         }
 639                 }
 640         }
 641 }
 642
 643
 644 /* get a rip socket
 645  */
 646 static int                              /* <0 or file descriptor */
 647 get_rip_sock(naddr addr,
 648              int serious)               /* 1=failure to bind is serious */
 649 {
 650         struct sockaddr_in rsin;
 651         unsigned char ttl;
 652         int s;
 653
 654
 655         if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
 656                 BADERR(1,"rip_sock = socket()");
 657
 658         memset(&rsin, 0, sizeof(rsin));
 659 #ifdef _HAVE_SIN_LEN
 660         rsin.sin_len = sizeof(rsin);
 661 #endif
 662         rsin.sin_family = AF_INET;
 663         rsin.sin_port = htons(RIP_PORT);
 664         rsin.sin_addr.s_addr = addr;
 665         if (bind(s, (struct sockaddr *)&rsin, sizeof(rsin)) < 0) {
 666                 if (serious)
 667                         BADERR(errno != EADDRINUSE, "bind(rip_sock)");
 668                 return -1;
 669         }
 670         fix_sock(s,"rip_sock");
 671
 672         ttl = 1;
 673         if (setsockopt(s, IPPROTO_IP, IP_MULTICAST_TTL,
 674                        &ttl, sizeof(ttl)) < 0)
 675                 DBGERR(1,"rip_sock setsockopt(IP_MULTICAST_TTL)");
 676
 677         return s;
 678 }
 679
 680
 681 /* turn off main RIP socket */
 682 void
 683 rip_off(void)
 684 {
 685         struct interface *ifp;
 686         naddr addr;
 687
 688
 689         if (rip_sock >= 0 && !mhome) {
 690                 trace_act("turn off RIP");
 691
 692                 (void)close(rip_sock);
 693                 rip_sock = -1;
 694
 695                 /* get non-broadcast sockets to listen to queries.
 696                  */
 697                 LIST_FOREACH(ifp, &ifnet, int_list) {
 698                         if (ifp->int_state & IS_REMOTE)
 699                                 continue;
 700                         if (ifp->int_rip_sock < 0) {
 701                                 addr = ((ifp->int_if_flags & IFF_POINTOPOINT)
 702                                         ? ifp->int_dstaddr
 703                                         : ifp->int_addr);
 704                                 ifp->int_rip_sock = get_rip_sock(addr, 0);
 705                         }
 706                 }
 707
 708                 fix_select();
 709
 710                 age(0);
 711         }
 712 }
 713
 714
 715 /* turn on RIP multicast input via an interface
 716  */
 717 static void
 718 rip_mcast_on(struct interface *ifp)
 719 {
 720         struct group_req gr;
 721         struct sockaddr_in *sin;
 722
 723         if (!IS_RIP_IN_OFF(ifp->int_state)
 724             && (ifp->int_if_flags & IFF_MULTICAST)
 725             && !(ifp->int_state & IS_ALIAS)) {
 726                 memset(&gr, 0, sizeof(gr));
 727                 gr.gr_interface = ifp->int_index;
 728                 sin = (struct sockaddr_in *)&gr.gr_group;
 729                 sin->sin_family = AF_INET;
 730 #ifdef _HAVE_SIN_LEN
 731                 sin->sin_len = sizeof(struct sockaddr_in);
 732 #endif
 733                 sin->sin_addr.s_addr = htonl(INADDR_RIP_GROUP);
 734                 if (setsockopt(rip_sock, IPPROTO_IP, MCAST_JOIN_GROUP,
 735                                &gr, sizeof(gr)) < 0)
 736                         LOGERR("setsockopt(MCAST_JOIN_GROUP RIP)");
 737         }
 738 }
 739
 740
 741 /* Prepare socket used for RIP.
 742  */
 743 void
 744 rip_on(struct interface *ifp)
 745 {
 746         /* If the main RIP socket is already alive, only start receiving
 747          * multicasts for this interface.
 748          */
 749         if (rip_sock >= 0) {
 750                 if (ifp != NULL)
 751                         rip_mcast_on(ifp);
 752                 return;
 753         }
 754
 755         /* If the main RIP socket is off and it makes sense to turn it on,
 756          * then turn it on for all of the interfaces.
 757          * It makes sense if either router discovery is off, or if
 758          * router discover is on and at most one interface is doing RIP.
 759          */
 760         if (rip_interfaces > 0 && (!rdisc_ok || rip_interfaces > 1)) {
 761                 trace_act("turn on RIP");
 762
 763                 /* Close all of the query sockets so that we can open
 764                  * the main socket.  SO_REUSEPORT is not a solution,
 765                  * since that would let two daemons bind to the broadcast
 766                  * socket.
 767                  */
 768                 LIST_FOREACH(ifp, &ifnet, int_list) {
 769                         if (ifp->int_rip_sock >= 0) {
 770                                 (void)close(ifp->int_rip_sock);
 771                                 ifp->int_rip_sock = -1;
 772                         }
 773                 }
 774
 775                 rip_sock = get_rip_sock(INADDR_ANY, 1);
 776                 rip_sock_mcast = NULL;
 777
 778                 /* Do not advertise anything until we have heard something
 779                  */
 780                 if (next_bcast.tv_sec < now.tv_sec+MIN_WAITTIME)
 781                         next_bcast.tv_sec = now.tv_sec+MIN_WAITTIME;
 782
 783                 LIST_FOREACH(ifp, &ifnet, int_list) {
 784                         ifp->int_query_time = NEVER;
 785                         rip_mcast_on(ifp);
 786                 }
 787                 ifinit_timer.tv_sec = now.tv_sec;
 788
 789         } else if (ifp != NULL
 790                    && !(ifp->int_state & IS_REMOTE)
 791                    && ifp->int_rip_sock < 0) {
 792                 /* RIP is off, so ensure there are sockets on which
 793                  * to listen for queries.
 794                  */
 795                 ifp->int_rip_sock = get_rip_sock(ifp->int_addr, 0);
 796         }
 797
 798         fix_select();
 799 }
 800
 801
 802 /* die if malloc(3) fails
 803  */
 804 void *
 805 rtmalloc(size_t size,
 806          const char *msg)
 807 {
 808         void *p = malloc(size);
 809         if (p == NULL)
 810                 logbad(1,"malloc(%lu) failed in %s", (u_long)size, msg);
 811         return p;
 812 }
 813
 814
 815 /* get a random instant in an interval
 816  */
 817 void
 818 intvl_random(struct timeval *tp,        /* put value here */
 819              u_long lo,                 /* value is after this second */
 820              u_long hi)                 /* and before this */
 821 {
 822         tp->tv_sec = (time_t)(hi == lo
 823                               ? lo
 824                               : (lo + arc4random_uniform(1 + hi - lo)));
 825         tp->tv_usec = arc4random_uniform(1000000);
 826 }
 827
 828
 829 void
 830 timevaladd(struct timeval *t1,
 831            struct timeval *t2)
 832 {
 833
 834         t1->tv_sec += t2->tv_sec;
 835         if ((t1->tv_usec += t2->tv_usec) >= 1000000) {
 836                 t1->tv_sec++;
 837                 t1->tv_usec -= 1000000;
 838         }
 839 }
 840
 841
 842 /* t1 = t2 - t3
 843  */
 844 static void
 845 timevalsub(struct timeval *t1,
 846            struct timeval *t2,
 847            struct timeval *t3)
 848 {
 849         t1->tv_sec = t2->tv_sec - t3->tv_sec;
 850         if ((t1->tv_usec = t2->tv_usec - t3->tv_usec) < 0) {
 851                 t1->tv_sec--;
 852                 t1->tv_usec += 1000000;
 853         }
 854 }
 855
 856
 857 /* put a message into the system log
 858  */
 859 void
 860 msglog(const char *p, ...)
 861 {
 862         va_list args;
 863
 864         trace_flush();
 865
 866         va_start(args, p);
 867         vsyslog(LOG_ERR, p, args);
 868         va_end(args);
 869         if (ftrace != NULL) {
 870                 if (ftrace == stdout)
 871                         (void)fputs("routed: ", ftrace);
 872                 va_start(args, p);
 873                 (void)vfprintf(ftrace, p, args);
 874                 va_end(args);
 875                 (void)fputc('\n', ftrace);
 876         }
 877 }
 878
 879
 880 /* Put a message about a bad system into the system log if
 881  * we have not complained about it recently.
 882  *
 883  * It is desirable to complain about all bad systems, but not too often.
 884  * In the worst case, it is not practical to keep track of all bad systems.
 885  * For example, there can be many systems with the wrong password.
 886  */
 887 void
 888 msglim(struct msg_limit *lim, naddr addr, const char *p, ...)
 889 {
 890         va_list args;
 891         int i;
 892         struct msg_sub *ms1, *ms;
 893         const char *p1;
 894
 895         /* look for the oldest slot in the table
 896          * or the slot for the bad router.
 897          */
 898         ms = ms1 = lim->subs;
 899         for (i = MSG_SUBJECT_N; ; i--, ms1++) {
 900                 if (i == 0) {
 901                         /* Reuse a slot at most once every 10 minutes.
 902                          */
 903                         if (lim->reuse > now.tv_sec) {
 904                                 ms = NULL;
 905                         } else {
 906                                 ms = ms1;
 907                                 lim->reuse = now.tv_sec + 10*60;
 908                         }
 909                         break;
 910                 }
 911                 if (ms->addr == addr) {
 912                         /* Repeat a complaint about a given system at
 913                          * most once an hour.
 914                          */
 915                         if (ms->until > now.tv_sec)
 916                                 ms = NULL;
 917                         break;
 918                 }
 919                 if (ms->until < ms1->until)
 920                         ms = ms1;
 921         }
 922         if (ms != NULL) {
 923                 ms->addr = addr;
 924                 ms->until = now.tv_sec + 60*60; /* 60 minutes */
 925
 926                 trace_flush();
 927                 for (p1 = p; *p1 == ' '; p1++)
 928                         continue;
 929                 va_start(args, p);
 930                 vsyslog(LOG_ERR, p1, args);
 931                 va_end(args);
 932         }
 933
 934         /* always display the message if tracing */
 935         if (ftrace != NULL) {
 936                 va_start(args, p);
 937                 (void)vfprintf(ftrace, p, args);
 938                 va_end(args);
 939                 (void)fputc('\n', ftrace);
 940         }
 941 }
 942
 943
 944 void
 945 logbad(int dump, const char *p, ...)
 946 {
 947         va_list args;
 948
 949         trace_flush();
 950
 951         va_start(args, p);
 952         vsyslog(LOG_ERR, p, args);
 953         va_end(args);
 954         (void)fputs("routed: ", stderr);
 955         va_start(args, p);
 956         (void)vfprintf(stderr, p, args);
 957         va_end(args);
 958         (void)fputs("; giving up\n",stderr);
 959         (void)fflush(stderr);
 960
 961         if (dump)
 962                 abort();
 963         exit(1);
 964 }