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. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgment:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  *
  33  * $FreeBSD: src/sbin/routed/main.c,v 1.11.2.1 2000/08/14 17:00:03 sheldonh Exp $
  34  * $DragonFly: src/sbin/routed/main.c,v 1.4 2005/03/16 21:21:34 cpressey Exp $
  35  */
  36
  37 #include "defs.h"
  38 #include "pathnames.h"
  39 #ifdef sgi
  40 #include "math.h"
  41 #endif
  42 #include <signal.h>
  43 #include <fcntl.h>
  44 #include <sys/file.h>
  45
  46 #if !defined(sgi) && !defined(__NetBSD__)
  47 char copyright[] =
  48 "@(#) Copyright (c) 1983, 1988, 1993\n\
  49         The Regents of the University of California.  All rights reserved.\n";
  50 static char sccsid[] __attribute__((unused)) = "@(#)main.c      8.1 (Berkeley) 6/5/93";
  51 #elif defined(__NetBSD__)
  52 __RCSID("$NetBSD$");
  53 __COPYRIGHT("@(#) Copyright (c) 1983, 1988, 1993\n\
  54         The Regents of the University of California.  All rights reserved.\n");
  55 #endif
  56
  57
  58 pid_t   mypid;
  59
  60 naddr   myaddr;                         /* system address */
  61 char    myname[MAXHOSTNAMELEN+1];
  62
  63 int     verbose;
  64
  65 int     supplier;                       /* supply or broadcast updates */
  66 int     supplier_set;
  67 int     ipforwarding = 1;               /* kernel forwarding on */
  68
  69 int     default_gateway;                /* 1=advertise default */
  70 int     background = 1;
  71 int     ridhosts;                       /* 1=reduce host routes */
  72 int     mhome;                          /* 1=want multi-homed host route */
  73 int     advertise_mhome;                /* 1=must continue advertising it */
  74 int     auth_ok = 1;                    /* 1=ignore auth if we do not care */
  75
  76 struct timeval epoch;                   /* when started */
  77 struct timeval clk, 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 struct timeval next_bcast;              /* next general broadcast */
  85 struct timeval no_flash = {             /* inhibit flash update */
  86         EPOCH+SUPPLY_INTERVAL, 0
  87 };
  88
  89 struct timeval flush_kern_timer;
  90
  91 fd_set  fdbits;
  92 int     sock_max;
  93 int     rip_sock = -1;                  /* RIP socket */
  94 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
 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_ODELAY, 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         gethostname(myname, sizeof(myname)-1);
 138         gethost(myname, &myaddr);
 139
 140         while ((n = getopt(argc, argv, "sqdghmpAtvT:F:P:")) != -1) {
 141                 switch (n) {
 142                 case 's':
 143                         supplier = 1;
 144                         supplier_set = 1;
 145                         break;
 146
 147                 case 'q':
 148                         supplier = 0;
 149                         supplier_set = 1;
 150                         break;
 151
 152                 case 'd':
 153                         background = 0;
 154                         break;
 155
 156                 case 'g':
 157                         memset(&parm, 0, sizeof(parm));
 158                         parm.parm_d_metric = 1;
 159                         cp = check_parms(&parm);
 160                         if (cp != 0)
 161                                 msglog("bad -g: %s", cp);
 162                         else
 163                                 default_gateway = 1;
 164                         break;
 165
 166                 case 'h':               /* suppress extra host routes */
 167                         ridhosts = 1;
 168                         break;
 169
 170                 case 'm':               /* advertise host route */
 171                         mhome = 1;      /* on multi-homed hosts */
 172                         break;
 173
 174                 case 'A':
 175                         /* Ignore authentication if we do not care.
 176                          * Crazy as it is, that is what RFC 1723 requires.
 177                          */
 178                         auth_ok = 0;
 179                         break;
 180
 181                 case 't':
 182                         new_tracelevel++;
 183                         break;
 184
 185                 case 'T':
 186                         tracename = optarg;
 187                         break;
 188
 189                 case 'F':               /* minimal routes for SLIP */
 190                         n = FAKE_METRIC;
 191                         p = strchr(optarg,',');
 192                         if (p && *p != '\0') {
 193                                 n = (int)strtoul(p+1, &q, 0);
 194                                 if (*q == '\0'
 195                                     && n <= HOPCNT_INFINITY-1
 196                                     && n >= 1)
 197                                         *p = '\0';
 198                         }
 199                         if (!getnet(optarg, &p_net, &p_mask)) {
 200                                 msglog("bad network; \"-F %s\"",
 201                                        optarg);
 202                                 break;
 203                         }
 204                         memset(&parm, 0, sizeof(parm));
 205                         parm.parm_net = p_net;
 206                         parm.parm_mask = p_mask;
 207                         parm.parm_d_metric = n;
 208                         cp = check_parms(&parm);
 209                         if (cp != 0)
 210                                 msglog("bad -F: %s", cp);
 211                         break;
 212
 213                 case 'P':
 214                         /* handle arbitrary parameters.
 215                          */
 216                         q = strdup(optarg);
 217                         cp = parse_parms(q, 0);
 218                         if (cp != 0)
 219                                 msglog("%s in \"-P %s\"", cp, optarg);
 220                         free(q);
 221                         break;
 222
 223                 case 'v':
 224                         /* display version */
 225                         verbose++;
 226                         msglog("version 2.22");
 227                         break;
 228
 229                 default:
 230                         goto usage;
 231                 }
 232         }
 233         argc -= optind;
 234         argv += optind;
 235
 236         if (tracename == 0 && argc >= 1) {
 237                 tracename = *argv++;
 238                 argc--;
 239         }
 240         if (tracename != 0 && tracename[0] == '\0')
 241                 goto usage;
 242         if (argc != 0) {
 243 usage:
 244                 logbad(0, "usage: routed [-sqdghmpAtv] [-T tracefile]"
 245                        " [-F net[,metric]] [-P parms]");
 246         }
 247         if (geteuid() != 0) {
 248                 if (verbose)
 249                         exit(0);
 250                 logbad(0, "requires UID 0");
 251         }
 252
 253         mib[0] = CTL_NET;
 254         mib[1] = PF_INET;
 255         mib[2] = IPPROTO_IP;
 256         mib[3] = IPCTL_FORWARDING;
 257         len = sizeof(ipforwarding);
 258         if (sysctl(mib, 4, &ipforwarding, &len, 0, 0) < 0)
 259                 LOGERR("sysctl(IPCTL_FORWARDING)");
 260
 261         if (!ipforwarding) {
 262                 if (supplier)
 263                         msglog("-s incompatible with ipforwarding=0");
 264                 if (default_gateway) {
 265                         msglog("-g incompatible with ipforwarding=0");
 266                         default_gateway = 0;
 267                 }
 268                 supplier = 0;
 269                 supplier_set = 1;
 270         }
 271         if (default_gateway) {
 272                 if (supplier_set && !supplier) {
 273                         msglog("-g and -q incompatible");
 274                 } else {
 275                         supplier = 1;
 276                         supplier_set = 1;
 277                 }
 278         }
 279
 280
 281         signal(SIGALRM, sigalrm);
 282         if (!background)
 283                 signal(SIGHUP, sigterm);    /* SIGHUP fatal during debugging */
 284         signal(SIGTERM, sigterm);
 285         signal(SIGINT, sigterm);
 286         signal(SIGUSR1, sigtrace_on);
 287         signal(SIGUSR2, sigtrace_off);
 288
 289         /* get into the background */
 290 #ifdef sgi
 291         if (0 > _daemonize(background ? 0 : (_DF_NOCHDIR|_DF_NOFORK),
 292                            STDIN_FILENO, STDOUT_FILENO, STDERR_FILENO))
 293                 BADERR(0, "_daemonize()");
 294 #else
 295         if (background && daemon(0, 1) < 0)
 296                 BADERR(0,"daemon()");
 297 #endif
 298
 299         mypid = getpid();
 300         srandom((int)(clk.tv_sec ^ clk.tv_usec ^ mypid));
 301
 302         /* prepare socket connected to the kernel.
 303          */
 304         rt_sock = socket(AF_ROUTE, SOCK_RAW, 0);
 305         if (rt_sock < 0)
 306                 BADERR(1,"rt_sock = socket()");
 307         if (fcntl(rt_sock, F_SETFL, O_NONBLOCK) == -1)
 308                 logbad(1, "fcntl(rt_sock) O_NONBLOCK: %s", strerror(errno));
 309         off = 0;
 310         if (setsockopt(rt_sock, SOL_SOCKET,SO_USELOOPBACK,
 311                        &off,sizeof(off)) < 0)
 312                 LOGERR("setsockopt(SO_USELOOPBACK,0)");
 313
 314         fix_select();
 315
 316
 317         if (tracename != 0) {
 318                 strncpy(inittracename, tracename, sizeof(inittracename)-1);
 319                 set_tracefile(inittracename, "%s", -1);
 320         } else {
 321                 tracelevel_msg("%s", -1);   /* turn on tracing to stdio */
 322         }
 323
 324         bufinit();
 325
 326         /* initialize radix tree */
 327         rtinit();
 328
 329         /* Pick a random part of the second for our output to minimize
 330          * collisions.
 331          *
 332          * Start broadcasting after hearing from other routers, and
 333          * at a random time so a bunch of systems do not get synchronized
 334          * after a power failure.
 335          */
 336         intvl_random(&next_bcast, EPOCH+MIN_WAITTIME, EPOCH+SUPPLY_INTERVAL);
 337         age_timer.tv_usec = next_bcast.tv_usec;
 338         age_timer.tv_sec = EPOCH+MIN_WAITTIME;
 339         rdisc_timer = next_bcast;
 340         ifinit_timer.tv_usec = next_bcast.tv_usec;
 341
 342         /* Collect an initial view of the world by checking the interface
 343          * configuration and the kludge file.
 344          */
 345         gwkludge();
 346         ifinit();
 347
 348         /* Ask for routes */
 349         rip_query();
 350         rdisc_sol();
 351
 352         /* Now turn off stdio if not tracing */
 353         if (new_tracelevel == 0)
 354                 trace_close(background);
 355
 356         /* Loop forever, listening and broadcasting.
 357          */
 358         for (;;) {
 359                 prev_clk = clk;
 360                 gettimeofday(&clk, 0);
 361                 if (prev_clk.tv_sec == clk.tv_sec
 362                     && prev_clk.tv_usec == clk.tv_usec+usec_fudge) {
 363                         /* Much of `routed` depends on time always advancing.
 364                          * On systems that do not guarantee that gettimeofday()
 365                          * produces unique timestamps even if called within
 366                          * a single tick, use trickery like that in classic
 367                          * BSD kernels.
 368                          */
 369                         clk.tv_usec += ++usec_fudge;
 370
 371                 } else {
 372                         usec_fudge = 0;
 373
 374                         timevalsub(&t2, &clk, &prev_clk);
 375                         if (t2.tv_sec < 0
 376                             || t2.tv_sec > wtime.tv_sec + 5) {
 377                                 /* Deal with time changes before other
 378                                  * housekeeping to keep everything straight.
 379                                  */
 380                                 dt = t2.tv_sec;
 381                                 if (dt > 0)
 382                                         dt -= wtime.tv_sec;
 383                                 trace_act("time changed by %d sec", (int)dt);
 384                                 epoch.tv_sec += dt;
 385                         }
 386                 }
 387                 timevalsub(&now, &clk, &epoch);
 388                 now_stale = now.tv_sec - STALE_TIME;
 389                 now_expire = now.tv_sec - EXPIRE_TIME;
 390                 now_garbage = now.tv_sec - GARBAGE_TIME;
 391
 392                 /* deal with signals that should affect tracing */
 393                 set_tracelevel();
 394
 395                 if (stopint != 0) {
 396                         rip_bcast(0);
 397                         rdisc_adv();
 398                         trace_off("exiting with signal %d", stopint);
 399                         exit(stopint | 128);
 400                 }
 401
 402                 /* look for new or dead interfaces */
 403                 timevalsub(&wtime, &ifinit_timer, &now);
 404                 if (wtime.tv_sec <= 0) {
 405                         wtime.tv_sec = 0;
 406                         ifinit();
 407                         rip_query();
 408                         continue;
 409                 }
 410
 411                 /* Check the kernel table occassionally for mysteriously
 412                  * evaporated routes
 413                  */
 414                 timevalsub(&t2, &flush_kern_timer, &now);
 415                 if (t2.tv_sec <= 0) {
 416                         flush_kern();
 417                         flush_kern_timer.tv_sec = (now.tv_sec
 418                                                    + CHECK_QUIET_INTERVAL);
 419                         continue;
 420                 }
 421                 if (timercmp(&t2, &wtime, <))
 422                         wtime = t2;
 423
 424                 /* If it is time, then broadcast our routes.
 425                  */
 426                 if (supplier || advertise_mhome) {
 427                         timevalsub(&t2, &next_bcast, &now);
 428                         if (t2.tv_sec <= 0) {
 429                                 /* Synchronize the aging and broadcast
 430                                  * timers to minimize awakenings
 431                                  */
 432                                 age(0);
 433
 434                                 rip_bcast(0);
 435
 436                                 /* It is desirable to send routing updates
 437                                  * regularly.  So schedule the next update
 438                                  * 30 seconds after the previous one was
 439                                  * scheduled, instead of 30 seconds after
 440                                  * the previous update was finished.
 441                                  * Even if we just started after discovering
 442                                  * a 2nd interface or were otherwise delayed,
 443                                  * pick a 30-second aniversary of the
 444                                  * original broadcast time.
 445                                  */
 446                                 n = 1 + (0-t2.tv_sec)/SUPPLY_INTERVAL;
 447                                 next_bcast.tv_sec += n*SUPPLY_INTERVAL;
 448
 449                                 continue;
 450                         }
 451
 452                         if (timercmp(&t2, &wtime, <))
 453                                 wtime = t2;
 454                 }
 455
 456                 /* If we need a flash update, either do it now or
 457                  * set the delay to end when it is time.
 458                  *
 459                  * If we are within MIN_WAITTIME seconds of a full update,
 460                  * do not bother.
 461                  */
 462                 if (need_flash
 463                     && supplier
 464                     && no_flash.tv_sec+MIN_WAITTIME < next_bcast.tv_sec) {
 465                         /* accurate to the millisecond */
 466                         if (!timercmp(&no_flash, &now, >))
 467                                 rip_bcast(1);
 468                         timevalsub(&t2, &no_flash, &now);
 469                         if (timercmp(&t2, &wtime, <))
 470                                 wtime = t2;
 471                 }
 472
 473                 /* trigger the main aging timer.
 474                  */
 475                 timevalsub(&t2, &age_timer, &now);
 476                 if (t2.tv_sec <= 0) {
 477                         age(0);
 478                         continue;
 479                 }
 480                 if (timercmp(&t2, &wtime, <))
 481                         wtime = t2;
 482
 483                 /* update the kernel routing table
 484                  */
 485                 timevalsub(&t2, &need_kern, &now);
 486                 if (t2.tv_sec <= 0) {
 487                         age(0);
 488                         continue;
 489                 }
 490                 if (timercmp(&t2, &wtime, <))
 491                         wtime = t2;
 492
 493                 /* take care of router discovery,
 494                  * but do it in the correct the millisecond
 495                  */
 496                 if (!timercmp(&rdisc_timer, &now, >)) {
 497                         rdisc_age(0);
 498                         continue;
 499                 }
 500                 timevalsub(&t2, &rdisc_timer, &now);
 501                 if (timercmp(&t2, &wtime, <))
 502                         wtime = t2;
 503
 504
 505                 /* wait for input or a timer to expire.
 506                  */
 507                 trace_flush();
 508                 ibits = fdbits;
 509                 n = select(sock_max, &ibits, 0, 0, &wtime);
 510                 if (n <= 0) {
 511                         if (n < 0 && errno != EINTR && errno != EAGAIN)
 512                                 BADERR(1,"select");
 513                         continue;
 514                 }
 515
 516                 if (FD_ISSET(rt_sock, &ibits)) {
 517                         read_rt();
 518                         n--;
 519                 }
 520                 if (rdisc_sock >= 0 && FD_ISSET(rdisc_sock, &ibits)) {
 521                         read_d();
 522                         n--;
 523                 }
 524                 if (rip_sock >= 0 && FD_ISSET(rip_sock, &ibits)) {
 525                         read_rip(rip_sock, 0);
 526                         n--;
 527                 }
 528
 529                 for (ifp = ifnet; n > 0 && 0 != ifp; ifp = ifp->int_next) {
 530                         if (ifp->int_rip_sock >= 0
 531                             && FD_ISSET(ifp->int_rip_sock, &ibits)) {
 532                                 read_rip(ifp->int_rip_sock, ifp);
 533                                 n--;
 534                         }
 535                 }
 536         }
 537 }
 538
 539
 540 /* ARGSUSED */
 541 void
 542 sigalrm(int s UNUSED)
 543 {
 544         /* Historically, SIGALRM would cause the daemon to check for
 545          * new and broken interfaces.
 546          */
 547         ifinit_timer.tv_sec = now.tv_sec;
 548         trace_act("SIGALRM");
 549 }
 550
 551
 552 /* watch for fatal signals */
 553 void
 554 sigterm(int sig)
 555 {
 556         stopint = sig;
 557         signal(sig, SIG_DFL);   /* catch it only once */
 558 }
 559
 560
 561 void
 562 fix_select(void)
 563 {
 564         struct interface *ifp;
 565
 566
 567         FD_ZERO(&fdbits);
 568         sock_max = 0;
 569
 570         FD_SET(rt_sock, &fdbits);
 571         if (sock_max <= rt_sock)
 572                 sock_max = rt_sock+1;
 573         if (rip_sock >= 0) {
 574                 FD_SET(rip_sock, &fdbits);
 575                 if (sock_max <= rip_sock)
 576                         sock_max = rip_sock+1;
 577         }
 578         for (ifp = ifnet; 0 != ifp; ifp = ifp->int_next) {
 579                 if (ifp->int_rip_sock >= 0) {
 580                         FD_SET(ifp->int_rip_sock, &fdbits);
 581                         if (sock_max <= ifp->int_rip_sock)
 582                                 sock_max = ifp->int_rip_sock+1;
 583                 }
 584         }
 585         if (rdisc_sock >= 0) {
 586                 FD_SET(rdisc_sock, &fdbits);
 587                 if (sock_max <= rdisc_sock)
 588                         sock_max = rdisc_sock+1;
 589         }
 590 }
 591
 592
 593 void
 594 fix_sock(int sock,
 595          const char *name)
 596 {
 597         int on;
 598 #define MIN_SOCKBUF (4*1024)
 599         static int rbuf;
 600
 601         if (fcntl(sock, F_SETFL, O_NONBLOCK) == -1)
 602                 logbad(1, "fcntl(%s) O_NONBLOCK: %s",
 603                        name, strerror(errno));
 604         on = 1;
 605         if (setsockopt(sock, SOL_SOCKET,SO_BROADCAST, &on,sizeof(on)) < 0)
 606                 msglog("setsockopt(%s,SO_BROADCAST): %s",
 607                        name, strerror(errno));
 608 #ifdef USE_PASSIFNAME
 609         on = 1;
 610         if (setsockopt(sock, SOL_SOCKET, SO_PASSIFNAME, &on,sizeof(on)) < 0)
 611                 msglog("setsockopt(%s,SO_PASSIFNAME): %s",
 612                        name, strerror(errno));
 613 #endif
 614
 615         if (rbuf >= MIN_SOCKBUF) {
 616                 if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
 617                                &rbuf, sizeof(rbuf)) < 0)
 618                         msglog("setsockopt(%s,SO_RCVBUF=%d): %s",
 619                                name, rbuf, strerror(errno));
 620         } else {
 621                 for (rbuf = 60*1024; ; rbuf -= 4096) {
 622                         if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
 623                                        &rbuf, sizeof(rbuf)) == 0) {
 624                                 trace_act("RCVBUF=%d", rbuf);
 625                                 break;
 626                         }
 627                         if (rbuf < MIN_SOCKBUF) {
 628                                 msglog("setsockopt(%s,SO_RCVBUF = %d): %s",
 629                                        name, rbuf, strerror(errno));
 630                                 break;
 631                         }
 632                 }
 633         }
 634 }
 635
 636
 637 /* get a rip socket
 638  */
 639 static int                              /* <0 or file descriptor */
 640 get_rip_sock(naddr addr,
 641              int serious)               /* 1=failure to bind is serious */
 642 {
 643         struct sockaddr_in in;
 644         unsigned char ttl;
 645         int s;
 646
 647
 648         if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
 649                 BADERR(1,"rip_sock = socket()");
 650
 651         memset(&in, 0, sizeof(in));
 652 #ifdef _HAVE_SIN_LEN
 653         in.sin_len = sizeof(in);
 654 #endif
 655         in.sin_family = AF_INET;
 656         in.sin_port = htons(RIP_PORT);
 657         in.sin_addr.s_addr = addr;
 658         if (bind(s, (struct sockaddr *)&in, sizeof(in)) < 0) {
 659                 if (serious)
 660                         BADERR(errno != EADDRINUSE, "bind(rip_sock)");
 661                 return -1;
 662         }
 663         fix_sock(s,"rip_sock");
 664
 665         ttl = 1;
 666         if (setsockopt(s, IPPROTO_IP, IP_MULTICAST_TTL,
 667                        &ttl, sizeof(ttl)) < 0)
 668                 DBGERR(1,"rip_sock setsockopt(IP_MULTICAST_TTL)");
 669
 670         return s;
 671 }
 672
 673
 674 /* turn off main RIP socket */
 675 void
 676 rip_off(void)
 677 {
 678         struct interface *ifp;
 679         naddr addr;
 680
 681
 682         if (rip_sock >= 0 && !mhome) {
 683                 trace_act("turn off RIP");
 684
 685                 close(rip_sock);
 686                 rip_sock = -1;
 687
 688                 /* get non-broadcast sockets to listen to queries.
 689                  */
 690                 for (ifp = ifnet; ifp != 0; ifp = ifp->int_next) {
 691                         if (ifp->int_state & IS_REMOTE)
 692                                 continue;
 693                         if (ifp->int_rip_sock < 0) {
 694                                 addr = ((ifp->int_if_flags & IFF_POINTOPOINT)
 695                                         ? ifp->int_dstaddr
 696                                         : ifp->int_addr);
 697                                 ifp->int_rip_sock = get_rip_sock(addr, 0);
 698                         }
 699                 }
 700
 701                 fix_select();
 702
 703                 age(0);
 704         }
 705 }
 706
 707
 708 /* turn on RIP multicast input via an interface
 709  */
 710 static void
 711 rip_mcast_on(struct interface *ifp)
 712 {
 713         struct ip_mreq m;
 714
 715         if (!IS_RIP_IN_OFF(ifp->int_state)
 716             && (ifp->int_if_flags & IFF_MULTICAST)
 717 #ifdef MCAST_PPP_BUG
 718             && !(ifp->int_if_flags & IFF_POINTOPOINT)
 719 #endif
 720             && !(ifp->int_state & IS_ALIAS)) {
 721                 m.imr_multiaddr.s_addr = htonl(INADDR_RIP_GROUP);
 722                 m.imr_interface.s_addr = ((ifp->int_if_flags & IFF_POINTOPOINT)
 723                                           ? ifp->int_dstaddr
 724                                           : ifp->int_addr);
 725                 if (setsockopt(rip_sock,IPPROTO_IP, IP_ADD_MEMBERSHIP,
 726                                &m, sizeof(m)) < 0)
 727                         LOGERR("setsockopt(IP_ADD_MEMBERSHIP RIP)");
 728         }
 729 }
 730
 731
 732 /* Prepare socket used for RIP.
 733  */
 734 void
 735 rip_on(struct interface *ifp)
 736 {
 737         /* If the main RIP socket is already alive, only start receiving
 738          * multicasts for this interface.
 739          */
 740         if (rip_sock >= 0) {
 741                 if (ifp != 0)
 742                         rip_mcast_on(ifp);
 743                 return;
 744         }
 745
 746         /* If the main RIP socket is off and it makes sense to turn it on,
 747          * then turn it on for all of the interfaces.
 748          * It makes sense if either router discovery is off, or if
 749          * router discover is on and at most one interface is doing RIP.
 750          */
 751         if (rip_interfaces > 0 && (!rdisc_ok || rip_interfaces > 1)) {
 752                 trace_act("turn on RIP");
 753
 754                 /* Close all of the query sockets so that we can open
 755                  * the main socket.  SO_REUSEPORT is not a solution,
 756                  * since that would let two daemons bind to the broadcast
 757                  * socket.
 758                  */
 759                 for (ifp = ifnet; ifp != 0; ifp = ifp->int_next) {
 760                         if (ifp->int_rip_sock >= 0) {
 761                                 close(ifp->int_rip_sock);
 762                                 ifp->int_rip_sock = -1;
 763                         }
 764                 }
 765
 766                 rip_sock = get_rip_sock(INADDR_ANY, 1);
 767                 rip_sock_mcast = 0;
 768
 769                 /* Do not advertise anything until we have heard something
 770                  */
 771                 if (next_bcast.tv_sec < now.tv_sec+MIN_WAITTIME)
 772                         next_bcast.tv_sec = now.tv_sec+MIN_WAITTIME;
 773
 774                 for (ifp = ifnet; ifp != 0; ifp = ifp->int_next) {
 775                         ifp->int_query_time = NEVER;
 776                         rip_mcast_on(ifp);
 777                 }
 778                 ifinit_timer.tv_sec = now.tv_sec;
 779
 780         } else if (ifp != 0
 781                    && !(ifp->int_state & IS_REMOTE)
 782                    && ifp->int_rip_sock < 0) {
 783                 /* RIP is off, so ensure there are sockets on which
 784                  * to listen for queries.
 785                  */
 786                 ifp->int_rip_sock = get_rip_sock(ifp->int_addr, 0);
 787         }
 788
 789         fix_select();
 790 }
 791
 792
 793 /* die if malloc(3) fails
 794  */
 795 void *
 796 rtmalloc(size_t size,
 797          const char *msg)
 798 {
 799         void *p = malloc(size);
 800         if (p == 0)
 801                 logbad(1,"malloc(%lu) failed in %s", (u_long)size, msg);
 802         return p;
 803 }
 804
 805
 806 /* get a random instant in an interval
 807  */
 808 void
 809 intvl_random(struct timeval *tp,        /* put value here */
 810              u_long lo,                 /* value is after this second */
 811              u_long hi)                 /* and before this */
 812 {
 813         tp->tv_sec = (time_t)(hi == lo
 814                               ? lo
 815                               : (lo + random() % ((hi - lo))));
 816         tp->tv_usec = random() % 1000000;
 817 }
 818
 819
 820 void
 821 timevaladd(struct timeval *t1,
 822            struct timeval *t2)
 823 {
 824
 825         t1->tv_sec += t2->tv_sec;
 826         if ((t1->tv_usec += t2->tv_usec) >= 1000000) {
 827                 t1->tv_sec++;
 828                 t1->tv_usec -= 1000000;
 829         }
 830 }
 831
 832
 833 /* t1 = t2 - t3
 834  */
 835 static void
 836 timevalsub(struct timeval *t1,
 837            struct timeval *t2,
 838            struct timeval *t3)
 839 {
 840         t1->tv_sec = t2->tv_sec - t3->tv_sec;
 841         if ((t1->tv_usec = t2->tv_usec - t3->tv_usec) < 0) {
 842                 t1->tv_sec--;
 843                 t1->tv_usec += 1000000;
 844         }
 845 }
 846
 847
 848 /* put a message into the system log
 849  */
 850 void
 851 msglog(const char *p, ...)
 852 {
 853         va_list args;
 854
 855         trace_flush();
 856
 857         va_start(args, p);
 858         vsyslog(LOG_ERR, p, args);
 859
 860         if (ftrace != 0) {
 861                 if (ftrace == stdout)
 862                         fputs("routed: ", ftrace);
 863                 vfprintf(ftrace, p, args);
 864                 fputc('\n', ftrace);
 865         }
 866 }
 867
 868
 869 /* Put a message about a bad system into the system log if
 870  * we have not complained about it recently.
 871  *
 872  * It is desirable to complain about all bad systems, but not too often.
 873  * In the worst case, it is not practical to keep track of all bad systems.
 874  * For example, there can be many systems with the wrong password.
 875  */
 876 void
 877 msglim(struct msg_limit *lim, naddr addr, const char *p, ...)
 878 {
 879         va_list args;
 880         int i;
 881         struct msg_sub *ms1, *ms;
 882         const char *p1;
 883
 884         va_start(args, p);
 885
 886         /* look for the oldest slot in the table
 887          * or the slot for the bad router.
 888          */
 889         ms = ms1 = lim->subs;
 890         for (i = MSG_SUBJECT_N; ; i--, ms1++) {
 891                 if (i == 0) {
 892                         /* Reuse a slot at most once every 10 minutes.
 893                          */
 894                         if (lim->reuse > now.tv_sec) {
 895                                 ms = 0;
 896                         } else {
 897                                 ms = ms1;
 898                                 lim->reuse = now.tv_sec + 10*60;
 899                         }
 900                         break;
 901                 }
 902                 if (ms->addr == addr) {
 903                         /* Repeat a complaint about a given system at
 904                          * most once an hour.
 905                          */
 906                         if (ms->until > now.tv_sec)
 907                                 ms = 0;
 908                         break;
 909                 }
 910                 if (ms->until < ms1->until)
 911                         ms = ms1;
 912         }
 913         if (ms != 0) {
 914                 ms->addr = addr;
 915                 ms->until = now.tv_sec + 60*60; /* 60 minutes */
 916
 917                 trace_flush();
 918                 for (p1 = p; *p1 == ' '; p1++)
 919                         continue;
 920                 vsyslog(LOG_ERR, p1, args);
 921         }
 922
 923         /* always display the message if tracing */
 924         if (ftrace != 0) {
 925                 vfprintf(ftrace, p, args);
 926                 fputc('\n', ftrace);
 927         }
 928 }
 929
 930
 931 void
 932 logbad(int dump, const char *p, ...)
 933 {
 934         va_list args;
 935
 936         trace_flush();
 937
 938         va_start(args, p);
 939         vsyslog(LOG_ERR, p, args);
 940
 941         fputs("routed: ", stderr);
 942         vfprintf(stderr, p, args);
 943         fputs("; giving up\n",stderr);
 944         fflush(stderr);
 945
 946         if (dump)
 947                 abort();
 948         exit(1);
 949 }