sbin/routed/main.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-3-Clause
   3  *
   4  * Copyright (c) 1983, 1988, 1993
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  *
  31  * $FreeBSD$
  32  */
  33
  34 #include "defs.h"
  35 #include "pathnames.h"
  36 #ifdef sgi
  37 #include "math.h"
  38 #endif
  39 #include <signal.h>
  40 #include <fcntl.h>
  41 #include <sys/file.h>
  42
  43 __COPYRIGHT("@(#) Copyright (c) 1983, 1988, 1993 "
  44             "The Regents of the University of California."
  45             "  All rights reserved.");
  46 #ifdef __NetBSD__
  47 __RCSID("$NetBSD$");
  48 #include <util.h>
  49 #elif defined(__FreeBSD__)
  50 __RCSID("$FreeBSD$");
  51 #else
  52 __RCSID("$Revision: 2.31 $");
  53 #ident "$Revision: 2.31 $"
  54 #endif
  55
  56 pid_t   mypid;
  57
  58 naddr   myaddr;                         /* system address */
  59 static char myname[MAXHOSTNAMELEN+1];
  60
  61 static int verbose;
  62
  63 int     supplier;                       /* supply or broadcast updates */
  64 int     supplier_set;
  65 static int ipforwarding = 1;            /* kernel forwarding on */
  66
  67 static int default_gateway;             /* 1=advertise default */
  68 static int background = 1;
  69 int     ridhosts;                       /* 1=reduce host routes */
  70 int     mhome;                          /* 1=want multi-homed host route */
  71 int     advertise_mhome;                /* 1=must continue advertising it */
  72 int     auth_ok = 1;                    /* 1=ignore auth if we do not care */
  73 int     insecure;                       /* Reply to special queries or not */
  74
  75 struct timeval epoch;                   /* when started */
  76 struct timeval clk;
  77 static struct timeval prev_clk;
  78 static int usec_fudge;
  79 struct timeval now;                     /* current idea of time */
  80 time_t  now_stale;
  81 time_t  now_expire;
  82 time_t  now_garbage;
  83
  84 static struct timeval next_bcast;       /* next general broadcast */
  85 struct timeval no_flash = {             /* inhibit flash update */
  86         EPOCH+SUPPLY_INTERVAL, 0
  87 };
  88
  89 static struct timeval flush_kern_timer;
  90
  91 static fd_set fdbits;
  92 static int sock_max;
  93 int     rip_sock = -1;                  /* RIP socket */
  94 const struct interface *rip_sock_mcast; /* current multicast interface */
  95 int     rt_sock;                        /* routing socket */
  96 int     rt_sock_seqno;
  97
  98
  99 static  int get_rip_sock(naddr, int);
 100 static void timevalsub(struct timeval *, struct timeval *, struct timeval *);
 101 static void sigalrm(int s UNUSED);
 102 static void sigterm(int sig);
 103
 104 int
 105 main(int argc,
 106      char *argv[])
 107 {
 108         int n, mib[4], off;
 109         size_t len;
 110         char *p, *q;
 111         const char *cp;
 112         struct timeval wtime, t2;
 113         time_t dt;
 114         fd_set ibits;
 115         naddr p_net, p_mask;
 116         struct interface *ifp;
 117         struct parm parm;
 118         char *tracename = 0;
 119
 120
 121         /* Some shells are badly broken and send SIGHUP to backgrounded
 122          * processes.
 123          */
 124         signal(SIGHUP, SIG_IGN);
 125
 126         openlog("routed", LOG_PID, LOG_DAEMON);
 127         ftrace = stdout;
 128
 129         gettimeofday(&clk, 0);
 130         prev_clk = clk;
 131         epoch = clk;
 132         epoch.tv_sec -= EPOCH;
 133         now.tv_sec = EPOCH;
 134         now_stale = EPOCH - STALE_TIME;
 135         now_expire = EPOCH - EXPIRE_TIME;
 136         now_garbage = EPOCH - GARBAGE_TIME;
 137         wtime.tv_sec = 0;
 138
 139         (void)gethostname(myname, sizeof(myname)-1);
 140         (void)gethost(myname, &myaddr);
 141
 142         while ((n = getopt(argc, argv, "isqdghmAtvT:F:P:")) != -1) {
 143                 switch (n) {
 144                 case 'i':
 145                         insecure++;
 146                         break;
 147                 case 's':
 148                         supplier = 1;
 149                         supplier_set = 1;
 150                         break;
 151
 152                 case 'q':
 153                         supplier = 0;
 154                         supplier_set = 1;
 155                         break;
 156
 157                 case 'd':
 158                         background = 0;
 159                         break;
 160
 161                 case 'g':
 162                         memset(&parm, 0, sizeof(parm));
 163                         parm.parm_d_metric = 1;
 164                         cp = check_parms(&parm);
 165                         if (cp != 0)
 166                                 msglog("bad -g: %s", cp);
 167                         else
 168                                 default_gateway = 1;
 169                         break;
 170
 171                 case 'h':               /* suppress extra host routes */
 172                         ridhosts = 1;
 173                         break;
 174
 175                 case 'm':               /* advertise host route */
 176                         mhome = 1;      /* on multi-homed hosts */
 177                         break;
 178
 179                 case 'A':
 180                         /* Ignore authentication if we do not care.
 181                          * Crazy as it is, that is what RFC 1723 requires.
 182                          */
 183                         auth_ok = 0;
 184                         break;
 185
 186                 case 't':
 187                         new_tracelevel++;
 188                         break;
 189
 190                 case 'T':
 191                         tracename = optarg;
 192                         break;
 193
 194                 case 'F':               /* minimal routes for SLIP */
 195                         n = FAKE_METRIC;
 196                         p = strchr(optarg,',');
 197                         if (p && *p != '\0') {
 198                                 n = (int)strtoul(p+1, &q, 0);
 199                                 if (*q == '\0'
 200                                     && n <= HOPCNT_INFINITY-1
 201                                     && n >= 1)
 202                                         *p = '\0';
 203                         }
 204                         if (!getnet(optarg, &p_net, &p_mask)) {
 205                                 msglog("bad network; \"-F %s\"",
 206                                        optarg);
 207                                 break;
 208                         }
 209                         memset(&parm, 0, sizeof(parm));
 210                         parm.parm_net = p_net;
 211                         parm.parm_mask = p_mask;
 212                         parm.parm_d_metric = n;
 213                         cp = check_parms(&parm);
 214                         if (cp != 0)
 215                                 msglog("bad -F: %s", cp);
 216                         break;
 217
 218                 case 'P':
 219                         /* handle arbitrary parameters.
 220                          */
 221                         q = strdup(optarg);
 222                         cp = parse_parms(q, 0);
 223                         if (cp != 0)
 224                                 msglog("%s in \"-P %s\"", cp, optarg);
 225                         free(q);
 226                         break;
 227
 228                 case 'v':
 229                         /* display version */
 230                         verbose++;
 231                         msglog("version 2.31");
 232                         break;
 233
 234                 default:
 235                         goto usage;
 236                 }
 237         }
 238         argc -= optind;
 239         argv += optind;
 240
 241         if (tracename == 0 && argc >= 1) {
 242                 tracename = *argv++;
 243                 argc--;
 244         }
 245         if (tracename != 0 && tracename[0] == '\0')
 246                 goto usage;
 247         if (argc != 0) {
 248 usage:
 249                 logbad(0, "usage: routed [-sqdghmAtv] [-T tracefile]"
 250                        " [-F net[,metric]] [-P parms]");
 251         }
 252         if (geteuid() != 0) {
 253                 if (verbose)
 254                         exit(0);
 255                 logbad(0, "requires UID 0");
 256         }
 257
 258         mib[0] = CTL_NET;
 259         mib[1] = PF_INET;
 260         mib[2] = IPPROTO_IP;
 261         mib[3] = IPCTL_FORWARDING;
 262         len = sizeof(ipforwarding);
 263         if (sysctl(mib, 4, &ipforwarding, &len, 0, 0) < 0)
 264                 LOGERR("sysctl(IPCTL_FORWARDING)");
 265
 266         if (!ipforwarding) {
 267                 if (supplier)
 268                         msglog("-s incompatible with ipforwarding=0");
 269                 if (default_gateway) {
 270                         msglog("-g incompatible with ipforwarding=0");
 271                         default_gateway = 0;
 272                 }
 273                 supplier = 0;
 274                 supplier_set = 1;
 275         }
 276         if (default_gateway) {
 277                 if (supplier_set && !supplier) {
 278                         msglog("-g and -q incompatible");
 279                 } else {
 280                         supplier = 1;
 281                         supplier_set = 1;
 282                 }
 283         }
 284
 285
 286         signal(SIGALRM, sigalrm);
 287         if (!background)
 288                 signal(SIGHUP, sigterm);    /* SIGHUP fatal during debugging */
 289         signal(SIGTERM, sigterm);
 290         signal(SIGINT, sigterm);
 291         signal(SIGUSR1, sigtrace_on);
 292         signal(SIGUSR2, sigtrace_off);
 293
 294         /* get into the background */
 295 #ifdef sgi
 296         if (0 > _daemonize(background ? 0 : (_DF_NOCHDIR|_DF_NOFORK),
 297                            STDIN_FILENO, STDOUT_FILENO, STDERR_FILENO))
 298                 BADERR(0, "_daemonize()");
 299 #else
 300         if (background && daemon(0, 1) < 0)
 301                 BADERR(0,"daemon()");
 302 #endif
 303
 304 #if defined(__NetBSD__)
 305         pidfile(0);
 306 #endif
 307         mypid = getpid();
 308
 309         /* prepare socket connected to the kernel.
 310          */
 311         rt_sock = socket(AF_ROUTE, SOCK_RAW, 0);
 312         if (rt_sock < 0)
 313                 BADERR(1,"rt_sock = socket()");
 314         if (fcntl(rt_sock, F_SETFL, O_NONBLOCK) == -1)
 315                 logbad(1, "fcntl(rt_sock) O_NONBLOCK: %s", strerror(errno));
 316         off = 0;
 317         if (setsockopt(rt_sock, SOL_SOCKET,SO_USELOOPBACK,
 318                        &off,sizeof(off)) < 0)
 319                 LOGERR("setsockopt(SO_USELOOPBACK,0)");
 320
 321         fix_select();
 322
 323
 324         if (tracename != 0) {
 325                 strncpy(inittracename, tracename, sizeof(inittracename)-1);
 326                 set_tracefile(inittracename, "%s", -1);
 327         } else {
 328                 tracelevel_msg("%s", -1);   /* turn on tracing to stdio */
 329         }
 330
 331         bufinit();
 332
 333         /* initialize radix tree */
 334         rtinit();
 335
 336         /* Pick a random part of the second for our output to minimize
 337          * collisions.
 338          *
 339          * Start broadcasting after hearing from other routers, and
 340          * at a random time so a bunch of systems do not get synchronized
 341          * after a power failure.
 342          */
 343         intvl_random(&next_bcast, EPOCH+MIN_WAITTIME, EPOCH+SUPPLY_INTERVAL);
 344         age_timer.tv_usec = next_bcast.tv_usec;
 345         age_timer.tv_sec = EPOCH+MIN_WAITTIME;
 346         rdisc_timer = next_bcast;
 347         ifinit_timer.tv_usec = next_bcast.tv_usec;
 348
 349         /* Collect an initial view of the world by checking the interface
 350          * configuration and the kludge file.
 351          */
 352         gwkludge();
 353         ifinit();
 354
 355         /* Ask for routes */
 356         rip_query();
 357         rdisc_sol();
 358
 359         /* Now turn off stdio if not tracing */
 360         if (new_tracelevel == 0)
 361                 trace_close(background);
 362
 363         /* Loop forever, listening and broadcasting.
 364          */
 365         for (;;) {
 366                 prev_clk = clk;
 367                 gettimeofday(&clk, 0);
 368                 if (prev_clk.tv_sec == clk.tv_sec
 369                     && prev_clk.tv_usec == clk.tv_usec+usec_fudge) {
 370                         /* Much of `routed` depends on time always advancing.
 371                          * On systems that do not guarantee that gettimeofday()
 372                          * produces unique timestamps even if called within
 373                          * a single tick, use trickery like that in classic
 374                          * BSD kernels.
 375                          */
 376                         clk.tv_usec += ++usec_fudge;
 377
 378                 } else {
 379                         usec_fudge = 0;
 380
 381                         timevalsub(&t2, &clk, &prev_clk);
 382                         if (t2.tv_sec < 0
 383                             || t2.tv_sec > wtime.tv_sec + 5) {
 384                                 /* Deal with time changes before other
 385                                  * housekeeping to keep everything straight.
 386                                  */
 387                                 dt = t2.tv_sec;
 388                                 if (dt > 0)
 389                                         dt -= wtime.tv_sec;
 390                                 trace_act("time changed by %d sec", (int)dt);
 391                                 epoch.tv_sec += dt;
 392                         }
 393                 }
 394                 timevalsub(&now, &clk, &epoch);
 395                 now_stale = now.tv_sec - STALE_TIME;
 396                 now_expire = now.tv_sec - EXPIRE_TIME;
 397                 now_garbage = now.tv_sec - GARBAGE_TIME;
 398
 399                 /* deal with signals that should affect tracing */
 400                 set_tracelevel();
 401
 402                 if (stopint != 0) {
 403                         rip_bcast(0);
 404                         rdisc_adv();
 405                         trace_off("exiting with signal %d", stopint);
 406                         exit(stopint | 128);
 407                 }
 408
 409                 /* look for new or dead interfaces */
 410                 timevalsub(&wtime, &ifinit_timer, &now);
 411                 if (wtime.tv_sec <= 0) {
 412                         wtime.tv_sec = 0;
 413                         ifinit();
 414                         rip_query();
 415                         continue;
 416                 }
 417
 418                 /* Check the kernel table occasionally for mysteriously
 419                  * evaporated routes
 420                  */
 421                 timevalsub(&t2, &flush_kern_timer, &now);
 422                 if (t2.tv_sec <= 0) {
 423                         flush_kern();
 424                         flush_kern_timer.tv_sec = (now.tv_sec
 425                                                    + CHECK_QUIET_INTERVAL);
 426                         continue;
 427                 }
 428                 if (timercmp(&t2, &wtime, <))
 429                         wtime = t2;
 430
 431                 /* If it is time, then broadcast our routes.
 432                  */
 433                 if (supplier || advertise_mhome) {
 434                         timevalsub(&t2, &next_bcast, &now);
 435                         if (t2.tv_sec <= 0) {
 436                                 /* Synchronize the aging and broadcast
 437                                  * timers to minimize awakenings
 438                                  */
 439                                 age(0);
 440
 441                                 rip_bcast(0);
 442
 443                                 /* It is desirable to send routing updates
 444                                  * regularly.  So schedule the next update
 445                                  * 30 seconds after the previous one was
 446                                  * scheduled, instead of 30 seconds after
 447                                  * the previous update was finished.
 448                                  * Even if we just started after discovering
 449                                  * a 2nd interface or were otherwise delayed,
 450                                  * pick a 30-second anniversary of the
 451                                  * original broadcast time.
 452                                  */
 453                                 n = 1 + (0-t2.tv_sec)/SUPPLY_INTERVAL;
 454                                 next_bcast.tv_sec += n*SUPPLY_INTERVAL;
 455
 456                                 continue;
 457                         }
 458
 459                         if (timercmp(&t2, &wtime, <))
 460                                 wtime = t2;
 461                 }
 462
 463                 /* If we need a flash update, either do it now or
 464                  * set the delay to end when it is time.
 465                  *
 466                  * If we are within MIN_WAITTIME seconds of a full update,
 467                  * do not bother.
 468                  */
 469                 if (need_flash
 470                     && supplier
 471                     && no_flash.tv_sec+MIN_WAITTIME < next_bcast.tv_sec) {
 472                         /* accurate to the millisecond */
 473                         if (!timercmp(&no_flash, &now, >))
 474                                 rip_bcast(1);
 475                         timevalsub(&t2, &no_flash, &now);
 476                         if (timercmp(&t2, &wtime, <))
 477                                 wtime = t2;
 478                 }
 479
 480                 /* trigger the main aging timer.
 481                  */
 482                 timevalsub(&t2, &age_timer, &now);
 483                 if (t2.tv_sec <= 0) {
 484                         age(0);
 485                         continue;
 486                 }
 487                 if (timercmp(&t2, &wtime, <))
 488                         wtime = t2;
 489
 490                 /* update the kernel routing table
 491                  */
 492                 timevalsub(&t2, &need_kern, &now);
 493                 if (t2.tv_sec <= 0) {
 494                         age(0);
 495                         continue;
 496                 }
 497                 if (timercmp(&t2, &wtime, <))
 498                         wtime = t2;
 499
 500                 /* take care of router discovery,
 501                  * but do it in the correct the millisecond
 502                  */
 503                 if (!timercmp(&rdisc_timer, &now, >)) {
 504                         rdisc_age(0);
 505                         continue;
 506                 }
 507                 timevalsub(&t2, &rdisc_timer, &now);
 508                 if (timercmp(&t2, &wtime, <))
 509                         wtime = t2;
 510
 511
 512                 /* wait for input or a timer to expire.
 513                  */
 514                 trace_flush();
 515                 ibits = fdbits;
 516                 n = select(sock_max, &ibits, 0, 0, &wtime);
 517                 if (n <= 0) {
 518                         if (n < 0 && errno != EINTR && errno != EAGAIN)
 519                                 BADERR(1,"select");
 520                         continue;
 521                 }
 522
 523                 if (FD_ISSET(rt_sock, &ibits)) {
 524                         read_rt();
 525                         n--;
 526                 }
 527                 if (rdisc_sock >= 0 && FD_ISSET(rdisc_sock, &ibits)) {
 528                         read_d();
 529                         n--;
 530                 }
 531                 if (rip_sock >= 0 && FD_ISSET(rip_sock, &ibits)) {
 532                         read_rip(rip_sock, 0);
 533                         n--;
 534                 }
 535
 536                 LIST_FOREACH(ifp, &ifnet, int_list) {
 537                         if (n <= 0)
 538                                 break;
 539                         if (ifp->int_rip_sock >= 0
 540                             && FD_ISSET(ifp->int_rip_sock, &ibits)) {
 541                                 read_rip(ifp->int_rip_sock, ifp);
 542                                 n--;
 543                         }
 544                 }
 545         }
 546 }
 547
 548
 549 /* ARGSUSED */
 550 static void
 551 sigalrm(int s UNUSED)
 552 {
 553         /* Historically, SIGALRM would cause the daemon to check for
 554          * new and broken interfaces.
 555          */
 556         ifinit_timer.tv_sec = now.tv_sec;
 557         trace_act("SIGALRM");
 558 }
 559
 560
 561 /* watch for fatal signals */
 562 static void
 563 sigterm(int sig)
 564 {
 565         stopint = sig;
 566         (void)signal(sig, SIG_DFL);     /* catch it only once */
 567 }
 568
 569
 570 void
 571 fix_select(void)
 572 {
 573         struct interface *ifp;
 574
 575
 576         FD_ZERO(&fdbits);
 577         sock_max = 0;
 578
 579         FD_SET(rt_sock, &fdbits);
 580         if (sock_max <= rt_sock)
 581                 sock_max = rt_sock+1;
 582         if (rip_sock >= 0) {
 583                 FD_SET(rip_sock, &fdbits);
 584                 if (sock_max <= rip_sock)
 585                         sock_max = rip_sock+1;
 586         }
 587         LIST_FOREACH(ifp, &ifnet, int_list) {
 588                 if (ifp->int_rip_sock >= 0) {
 589                         FD_SET(ifp->int_rip_sock, &fdbits);
 590                         if (sock_max <= ifp->int_rip_sock)
 591                                 sock_max = ifp->int_rip_sock+1;
 592                 }
 593         }
 594         if (rdisc_sock >= 0) {
 595                 FD_SET(rdisc_sock, &fdbits);
 596                 if (sock_max <= rdisc_sock)
 597                         sock_max = rdisc_sock+1;
 598         }
 599 }
 600
 601
 602 void
 603 fix_sock(int sock,
 604          const char *name)
 605 {
 606         int on;
 607 #define MIN_SOCKBUF (4*1024)
 608         static int rbuf;
 609
 610         if (fcntl(sock, F_SETFL, O_NONBLOCK) == -1)
 611                 logbad(1, "fcntl(%s) O_NONBLOCK: %s",
 612                        name, strerror(errno));
 613         on = 1;
 614         if (setsockopt(sock, SOL_SOCKET,SO_BROADCAST, &on,sizeof(on)) < 0)
 615                 msglog("setsockopt(%s,SO_BROADCAST): %s",
 616                        name, strerror(errno));
 617 #ifdef USE_PASSIFNAME
 618         on = 1;
 619         if (setsockopt(sock, SOL_SOCKET, SO_PASSIFNAME, &on,sizeof(on)) < 0)
 620                 msglog("setsockopt(%s,SO_PASSIFNAME): %s",
 621                        name, strerror(errno));
 622 #endif
 623
 624         if (rbuf >= MIN_SOCKBUF) {
 625                 if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
 626                                &rbuf, sizeof(rbuf)) < 0)
 627                         msglog("setsockopt(%s,SO_RCVBUF=%d): %s",
 628                                name, rbuf, strerror(errno));
 629         } else {
 630                 for (rbuf = 60*1024; ; rbuf -= 4096) {
 631                         if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
 632                                        &rbuf, sizeof(rbuf)) == 0) {
 633                                 trace_act("RCVBUF=%d", rbuf);
 634                                 break;
 635                         }
 636                         if (rbuf < MIN_SOCKBUF) {
 637                                 msglog("setsockopt(%s,SO_RCVBUF = %d): %s",
 638                                        name, rbuf, strerror(errno));
 639                                 break;
 640                         }
 641                 }
 642         }
 643 }
 644
 645
 646 /* get a rip socket
 647  */
 648 static int                              /* <0 or file descriptor */
 649 get_rip_sock(naddr addr,
 650              int serious)               /* 1=failure to bind is serious */
 651 {
 652         struct sockaddr_in rsin;
 653         unsigned char ttl;
 654         int s;
 655
 656
 657         if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
 658                 BADERR(1,"rip_sock = socket()");
 659
 660         memset(&rsin, 0, sizeof(rsin));
 661 #ifdef _HAVE_SIN_LEN
 662         rsin.sin_len = sizeof(rsin);
 663 #endif
 664         rsin.sin_family = AF_INET;
 665         rsin.sin_port = htons(RIP_PORT);
 666         rsin.sin_addr.s_addr = addr;
 667         if (bind(s, (struct sockaddr *)&rsin, sizeof(rsin)) < 0) {
 668                 if (serious)
 669                         BADERR(errno != EADDRINUSE, "bind(rip_sock)");
 670                 close(s);
 671                 return -1;
 672         }
 673         fix_sock(s,"rip_sock");
 674
 675         ttl = 1;
 676         if (setsockopt(s, IPPROTO_IP, IP_MULTICAST_TTL,
 677                        &ttl, sizeof(ttl)) < 0)
 678                 DBGERR(1,"rip_sock setsockopt(IP_MULTICAST_TTL)");
 679
 680         return s;
 681 }
 682
 683
 684 /* turn off main RIP socket */
 685 void
 686 rip_off(void)
 687 {
 688         struct interface *ifp;
 689         naddr addr;
 690
 691
 692         if (rip_sock >= 0 && !mhome) {
 693                 trace_act("turn off RIP");
 694
 695                 (void)close(rip_sock);
 696                 rip_sock = -1;
 697
 698                 /* get non-broadcast sockets to listen to queries.
 699                  */
 700                 LIST_FOREACH(ifp, &ifnet, int_list) {
 701                         if (ifp->int_state & IS_REMOTE)
 702                                 continue;
 703                         if (ifp->int_rip_sock < 0) {
 704                                 addr = ((ifp->int_if_flags & IFF_POINTOPOINT)
 705                                         ? ifp->int_dstaddr
 706                                         : ifp->int_addr);
 707                                 ifp->int_rip_sock = get_rip_sock(addr, 0);
 708                         }
 709                 }
 710
 711                 fix_select();
 712
 713                 age(0);
 714         }
 715 }
 716
 717
 718 /* turn on RIP multicast input via an interface
 719  */
 720 static void
 721 rip_mcast_on(struct interface *ifp)
 722 {
 723         struct group_req gr;
 724         struct sockaddr_in *sin;
 725
 726         if (!IS_RIP_IN_OFF(ifp->int_state)
 727             && (ifp->int_if_flags & IFF_MULTICAST)
 728             && !(ifp->int_state & IS_ALIAS)) {
 729                 memset(&gr, 0, sizeof(gr));
 730                 gr.gr_interface = ifp->int_index;
 731                 sin = (struct sockaddr_in *)&gr.gr_group;
 732                 sin->sin_family = AF_INET;
 733 #ifdef _HAVE_SIN_LEN
 734                 sin->sin_len = sizeof(struct sockaddr_in);
 735 #endif
 736                 sin->sin_addr.s_addr = htonl(INADDR_RIP_GROUP);
 737                 if (setsockopt(rip_sock, IPPROTO_IP, MCAST_JOIN_GROUP,
 738                                &gr, sizeof(gr)) < 0)
 739                         LOGERR("setsockopt(MCAST_JOIN_GROUP RIP)");
 740         }
 741 }
 742
 743
 744 /* Prepare socket used for RIP.
 745  */
 746 void
 747 rip_on(struct interface *ifp)
 748 {
 749         /* If the main RIP socket is already alive, only start receiving
 750          * multicasts for this interface.
 751          */
 752         if (rip_sock >= 0) {
 753                 if (ifp != NULL)
 754                         rip_mcast_on(ifp);
 755                 return;
 756         }
 757
 758         /* If the main RIP socket is off and it makes sense to turn it on,
 759          * then turn it on for all of the interfaces.
 760          * It makes sense if either router discovery is off, or if
 761          * router discover is on and at most one interface is doing RIP.
 762          */
 763         if (rip_interfaces > 0 && (!rdisc_ok || rip_interfaces > 1)) {
 764                 trace_act("turn on RIP");
 765
 766                 /* Close all of the query sockets so that we can open
 767                  * the main socket.  SO_REUSEPORT is not a solution,
 768                  * since that would let two daemons bind to the broadcast
 769                  * socket.
 770                  */
 771                 LIST_FOREACH(ifp, &ifnet, int_list) {
 772                         if (ifp->int_rip_sock >= 0) {
 773                                 (void)close(ifp->int_rip_sock);
 774                                 ifp->int_rip_sock = -1;
 775                         }
 776                 }
 777
 778                 rip_sock = get_rip_sock(INADDR_ANY, 1);
 779                 rip_sock_mcast = NULL;
 780
 781                 /* Do not advertise anything until we have heard something
 782                  */
 783                 if (next_bcast.tv_sec < now.tv_sec+MIN_WAITTIME)
 784                         next_bcast.tv_sec = now.tv_sec+MIN_WAITTIME;
 785
 786                 LIST_FOREACH(ifp, &ifnet, int_list) {
 787                         ifp->int_query_time = NEVER;
 788                         rip_mcast_on(ifp);
 789                 }
 790                 ifinit_timer.tv_sec = now.tv_sec;
 791
 792         } else if (ifp != NULL
 793                    && !(ifp->int_state & IS_REMOTE)
 794                    && ifp->int_rip_sock < 0) {
 795                 /* RIP is off, so ensure there are sockets on which
 796                  * to listen for queries.
 797                  */
 798                 ifp->int_rip_sock = get_rip_sock(ifp->int_addr, 0);
 799         }
 800
 801         fix_select();
 802 }
 803
 804
 805 /* die if malloc(3) fails
 806  */
 807 void *
 808 rtmalloc(size_t size,
 809          const char *msg)
 810 {
 811         void *p = malloc(size);
 812         if (p == NULL)
 813                 logbad(1,"malloc(%lu) failed in %s", (u_long)size, msg);
 814         return p;
 815 }
 816
 817
 818 /* get a random instant in an interval
 819  */
 820 void
 821 intvl_random(struct timeval *tp,        /* put value here */
 822              u_long lo,                 /* value is after this second */
 823              u_long hi)                 /* and before this */
 824 {
 825         tp->tv_sec = (time_t)(hi == lo
 826                               ? lo
 827                               : (lo + arc4random_uniform(1 + hi - lo)));
 828         tp->tv_usec = arc4random_uniform(1000000);
 829 }
 830
 831
 832 void
 833 timevaladd(struct timeval *t1,
 834            struct timeval *t2)
 835 {
 836
 837         t1->tv_sec += t2->tv_sec;
 838         if ((t1->tv_usec += t2->tv_usec) >= 1000000) {
 839                 t1->tv_sec++;
 840                 t1->tv_usec -= 1000000;
 841         }
 842 }
 843
 844
 845 /* t1 = t2 - t3
 846  */
 847 static void
 848 timevalsub(struct timeval *t1,
 849            struct timeval *t2,
 850            struct timeval *t3)
 851 {
 852         t1->tv_sec = t2->tv_sec - t3->tv_sec;
 853         if ((t1->tv_usec = t2->tv_usec - t3->tv_usec) < 0) {
 854                 t1->tv_sec--;
 855                 t1->tv_usec += 1000000;
 856         }
 857 }
 858
 859
 860 /* put a message into the system log
 861  */
 862 void
 863 msglog(const char *p, ...)
 864 {
 865         va_list args;
 866
 867         trace_flush();
 868
 869         va_start(args, p);
 870         vsyslog(LOG_ERR, p, args);
 871         va_end(args);
 872         if (ftrace != NULL) {
 873                 if (ftrace == stdout)
 874                         (void)fputs("routed: ", ftrace);
 875                 va_start(args, p);
 876                 (void)vfprintf(ftrace, p, args);
 877                 va_end(args);
 878                 (void)fputc('\n', ftrace);
 879         }
 880 }
 881
 882
 883 /* Put a message about a bad system into the system log if
 884  * we have not complained about it recently.
 885  *
 886  * It is desirable to complain about all bad systems, but not too often.
 887  * In the worst case, it is not practical to keep track of all bad systems.
 888  * For example, there can be many systems with the wrong password.
 889  */
 890 void
 891 msglim(struct msg_limit *lim, naddr addr, const char *p, ...)
 892 {
 893         va_list args;
 894         int i;
 895         struct msg_sub *ms1, *ms;
 896         const char *p1;
 897
 898         /* look for the oldest slot in the table
 899          * or the slot for the bad router.
 900          */
 901         ms = ms1 = lim->subs;
 902         for (i = MSG_SUBJECT_N; ; i--, ms1++) {
 903                 if (i == 0) {
 904                         /* Reuse a slot at most once every 10 minutes.
 905                          */
 906                         if (lim->reuse > now.tv_sec) {
 907                                 ms = NULL;
 908                         } else {
 909                                 ms = ms1;
 910                                 lim->reuse = now.tv_sec + 10*60;
 911                         }
 912                         break;
 913                 }
 914                 if (ms->addr == addr) {
 915                         /* Repeat a complaint about a given system at
 916                          * most once an hour.
 917                          */
 918                         if (ms->until > now.tv_sec)
 919                                 ms = NULL;
 920                         break;
 921                 }
 922                 if (ms->until < ms1->until)
 923                         ms = ms1;
 924         }
 925         if (ms != NULL) {
 926                 ms->addr = addr;
 927                 ms->until = now.tv_sec + 60*60; /* 60 minutes */
 928
 929                 trace_flush();
 930                 for (p1 = p; *p1 == ' '; p1++)
 931                         continue;
 932                 va_start(args, p);
 933                 vsyslog(LOG_ERR, p1, args);
 934                 va_end(args);
 935         }
 936
 937         /* always display the message if tracing */
 938         if (ftrace != NULL) {
 939                 va_start(args, p);
 940                 (void)vfprintf(ftrace, p, args);
 941                 va_end(args);
 942                 (void)fputc('\n', ftrace);
 943         }
 944 }
 945
 946
 947 void
 948 logbad(int dump, const char *p, ...)
 949 {
 950         va_list args;
 951
 952         trace_flush();
 953
 954         va_start(args, p);
 955         vsyslog(LOG_ERR, p, args);
 956         va_end(args);
 957         (void)fputs("routed: ", stderr);
 958         va_start(args, p);
 959         (void)vfprintf(stderr, p, args);
 960         va_end(args);
 961         (void)fputs("; giving up\n",stderr);
 962         (void)fflush(stderr);
 963
 964         if (dump)
 965                 abort();
 966         exit(1);
 967 }