sbin/routed/main.c

   1 /*      $NetBSD: main.c,v 1.40 2008/07/20 01:20:23 lukem Exp $  */
   2
   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. All advertising materials mentioning features or use of this software
  16  *    must display the following acknowledgment:
  17  *      This product includes software developed by the University of
  18  *      California, Berkeley and its contributors.
  19  * 4. Neither the name of the University nor the names of its contributors
  20  *    may be used to endorse or promote products derived from this software
  21  *    without specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  */
  35
  36 #include "defs.h"
  37 #include "pathnames.h"
  38 #ifdef sgi
  39 #include "math.h"
  40 #endif
  41 #if defined(__NetBSD__)
  42 #include <util.h>
  43 #endif
  44 #include <signal.h>
  45 #include <fcntl.h>
  46 #include <sys/file.h>
  47
  48 __COPYRIGHT("@(#) Copyright (c) 1983, 1988, 1993\
  49  The Regents of the University of California.  All rights reserved.");
  50 #ifdef __NetBSD__
  51 __RCSID("$NetBSD: main.c,v 1.40 2008/07/20 01:20:23 lukem Exp $");
  52 #elif defined(__FreeBSD__)
  53 __RCSID("$FreeBSD$");
  54 #else
  55 __RCSID("Revision: 2.27 ");
  56 #ident "Revision: 2.27 "
  57 #endif
  58
  59 pid_t   mypid;
  60
  61 naddr   myaddr;                         /* system address */
  62 char    myname[MAXHOSTNAMELEN+1];
  63
  64 int     verbose;
  65
  66 int     supplier;                       /* supply or broadcast updates */
  67 int     supplier_set;
  68 int     ipforwarding = 1;               /* kernel forwarding on */
  69
  70 int     default_gateway;                /* 1=advertise default */
  71 int     background = 1;
  72 int     ridhosts;                       /* 1=reduce host routes */
  73 int     mhome;                          /* 1=want multi-homed host route */
  74 int     advertise_mhome;                /* 1=must continue advertising it */
  75 int     auth_ok = 1;                    /* 1=ignore auth if we do not care */
  76
  77 struct timeval epoch;                   /* when started */
  78 struct timeval clk, prev_clk;
  79 static int usec_fudge;
  80 struct timeval now;                     /* current idea of time */
  81 time_t  now_stale;
  82 time_t  now_expire;
  83 time_t  now_garbage;
  84
  85 struct timeval next_bcast;              /* next general broadcast */
  86 struct timeval no_flash = {             /* inhibit flash update */
  87         EPOCH+SUPPLY_INTERVAL, 0
  88 };
  89
  90 struct timeval flush_kern_timer;
  91
  92 fd_set  *fdbitsp;
  93 int     sock_max;
  94 int     rip_sock = -1;                  /* RIP socket */
  95 struct interface *rip_sock_mcast;       /* current multicast interface */
  96 int     rt_sock;                        /* routing socket */
  97 int     rt_sock_seqno;
  98
  99
 100 static  int get_rip_sock(naddr, int);
 101 static void timevalsub(struct timeval *, struct timeval *, struct timeval *);
 102
 103 int
 104 main(int argc,
 105      char *argv[])
 106 {
 107         int n, mib[4], off;
 108         size_t len;
 109         char *p, *q;
 110         const char *cp;
 111         struct timeval wtime, t2;
 112         time_t dt;
 113         fd_set *ibitsp = NULL;
 114         naddr p_net, p_mask;
 115         struct interface *ifp;
 116         struct parm parm;
 117         char *tracename = 0;
 118
 119
 120         /* Some shells are badly broken and send SIGHUP to backgrounded
 121          * processes.
 122          */
 123         signal(SIGHUP, SIG_IGN);
 124
 125         openlog("routed", LOG_PID, LOG_DAEMON);
 126         ftrace = stdout;
 127
 128         gettimeofday(&clk, 0);
 129         prev_clk = clk;
 130         epoch = clk;
 131         epoch.tv_sec -= EPOCH;
 132         now.tv_sec = EPOCH;
 133         now_stale = EPOCH - STALE_TIME;
 134         now_expire = EPOCH - EXPIRE_TIME;
 135         now_garbage = EPOCH - GARBAGE_TIME;
 136         wtime.tv_sec = 0;
 137
 138         (void)gethostname(myname, sizeof(myname) - 1);
 139         (void)gethost(myname, &myaddr);
 140
 141         while ((n = getopt(argc, argv, "sqdghmAtvT:F:P:")) != -1) {
 142                 switch (n) {
 143                 case 's':
 144                         supplier = 1;
 145                         supplier_set = 1;
 146                         break;
 147
 148                 case 'q':
 149                         supplier = 0;
 150                         supplier_set = 1;
 151                         break;
 152
 153                 case 'd':
 154                         background = 0;
 155                         break;
 156
 157                 case 'g':
 158                         memset(&parm, 0, sizeof(parm));
 159                         parm.parm_d_metric = 1;
 160                         cp = check_parms(&parm);
 161                         if (cp != 0)
 162                                 msglog("bad -g: %s", cp);
 163                         else
 164                                 default_gateway = 1;
 165                         break;
 166
 167                 case 'h':               /* suppress extra host routes */
 168                         ridhosts = 1;
 169                         break;
 170
 171                 case 'm':               /* advertise host route */
 172                         mhome = 1;      /* on multi-homed hosts */
 173                         break;
 174
 175                 case 'A':
 176                         /* Ignore authentication if we do not care.
 177                          * Crazy as it is, that is what RFC 1723 requires.
 178                          */
 179                         auth_ok = 0;
 180                         break;
 181
 182                 case 't':
 183                         new_tracelevel++;
 184                         break;
 185
 186                 case 'T':
 187                         tracename = optarg;
 188                         break;
 189
 190                 case 'F':               /* minimal routes for SLIP */
 191                         n = FAKE_METRIC;
 192                         p = strchr(optarg,',');
 193                         if (p && *p != '\0') {
 194                                 n = (int)strtoul(p+1, &q, 0);
 195                                 if (*q == '\0'
 196                                     && n <= HOPCNT_INFINITY-1
 197                                     && n >= 1)
 198                                         *p = '\0';
 199                         }
 200                         if (!getnet(optarg, &p_net, &p_mask)) {
 201                                 msglog("bad network; \"-F %s\"",
 202                                        optarg);
 203                                 break;
 204                         }
 205                         memset(&parm, 0, sizeof(parm));
 206                         parm.parm_net = p_net;
 207                         parm.parm_mask = p_mask;
 208                         parm.parm_d_metric = n;
 209                         cp = check_parms(&parm);
 210                         if (cp != 0)
 211                                 msglog("bad -F: %s", cp);
 212                         break;
 213
 214                 case 'P':
 215                         /* handle arbitrary parameters.
 216                          */
 217                         q = strdup(optarg);
 218                         cp = parse_parms(q, 0);
 219                         if (cp != 0)
 220                                 msglog("%s in \"-P %s\"", cp, optarg);
 221                         free(q);
 222                         break;
 223
 224                 case 'v':
 225                         /* display version */
 226                         verbose++;
 227                         msglog("version 2.32");
 228                         break;
 229
 230                 default:
 231                         goto usage;
 232                 }
 233         }
 234         argc -= optind;
 235         argv += optind;
 236
 237         if (tracename == 0 && argc >= 1) {
 238                 tracename = *argv++;
 239                 argc--;
 240         }
 241         if (tracename != 0 && tracename[0] == '\0')
 242                 goto usage;
 243         if (argc != 0) {
 244 usage:
 245                 logbad(0, "usage: routed [-sqdghmAtv] [-T tracefile]"
 246                        " [-F net[/mask[,metric]]] [-P parms]");
 247         }
 248         if (geteuid() != 0) {
 249                 if (verbose)
 250                         exit(0);
 251                 logbad(0, "requires UID 0");
 252         }
 253
 254         mib[0] = CTL_NET;
 255         mib[1] = PF_INET;
 256         mib[2] = IPPROTO_IP;
 257         mib[3] = IPCTL_FORWARDING;
 258         len = sizeof(ipforwarding);
 259         if (sysctl(mib, 4, &ipforwarding, &len, 0, 0) < 0)
 260                 LOGERR("sysctl(IPCTL_FORWARDING)");
 261
 262         if (!ipforwarding) {
 263                 if (supplier)
 264                         msglog("-s incompatible with ipforwarding=0");
 265                 if (default_gateway) {
 266                         msglog("-g incompatible with ipforwarding=0");
 267                         default_gateway = 0;
 268                 }
 269                 supplier = 0;
 270                 supplier_set = 1;
 271         }
 272         if (default_gateway) {
 273                 if (supplier_set && !supplier) {
 274                         msglog("-g and -q incompatible");
 275                 } else {
 276                         supplier = 1;
 277                         supplier_set = 1;
 278                 }
 279         }
 280
 281
 282         signal(SIGALRM, sigalrm);
 283         if (!background)
 284                 signal(SIGHUP, sigterm);    /* SIGHUP fatal during debugging */
 285         signal(SIGTERM, sigterm);
 286         signal(SIGINT, sigterm);
 287         signal(SIGUSR1, sigtrace_on);
 288         signal(SIGUSR2, sigtrace_off);
 289
 290         /* get into the background */
 291 #ifdef sgi
 292         if (0 > _daemonize(background ? 0 : (_DF_NOCHDIR|_DF_NOFORK),
 293                            STDIN_FILENO, STDOUT_FILENO, STDERR_FILENO))
 294                 BADERR(0, "_daemonize()");
 295 #else
 296         if (background && daemon(0, 1) < 0)
 297                 BADERR(0,"daemon()");
 298 #endif
 299
 300 #if defined(__NetBSD__)
 301         pidfile(NULL);
 302 #endif
 303         mypid = getpid();
 304
 305         /* prepare socket connected to the kernel.
 306          */
 307         rt_sock = socket(AF_ROUTE, SOCK_RAW, 0);
 308         if (rt_sock < 0)
 309                 BADERR(1,"rt_sock = socket()");
 310         if (fcntl(rt_sock, F_SETFL, O_NONBLOCK) == -1)
 311                 logbad(1, "fcntl(rt_sock) O_NONBLOCK: %s", strerror(errno));
 312         off = 0;
 313         if (setsockopt(rt_sock, SOL_SOCKET,SO_USELOOPBACK,
 314                        &off,sizeof(off)) < 0)
 315                 LOGERR("setsockopt(SO_USELOOPBACK,0)");
 316
 317         fix_select();
 318
 319
 320         if (tracename != 0) {
 321                 strlcpy(inittracename, tracename, sizeof(inittracename));
 322                 set_tracefile(inittracename, "%s", -1);
 323         } else {
 324                 tracelevel_msg("%s", -1);   /* turn on tracing to stdio */
 325         }
 326
 327         bufinit();
 328
 329         /* initialize radix tree */
 330         rtinit();
 331
 332         /* Pick a random part of the second for our output to minimize
 333          * collisions.
 334          *
 335          * Start broadcasting after hearing from other routers, and
 336          * at a random time so a bunch of systems do not get synchronized
 337          * after a power failure.
 338          */
 339         intvl_random(&next_bcast, EPOCH+MIN_WAITTIME, EPOCH+SUPPLY_INTERVAL);
 340         age_timer.tv_usec = next_bcast.tv_usec;
 341         age_timer.tv_sec = EPOCH+MIN_WAITTIME;
 342         rdisc_timer = next_bcast;
 343         ifinit_timer.tv_usec = next_bcast.tv_usec;
 344
 345         /* Collect an initial view of the world by checking the interface
 346          * configuration and the kludge file.
 347          */
 348         gwkludge();
 349         ifinit();
 350
 351         /* Ask for routes */
 352         rip_query();
 353         rdisc_sol();
 354
 355         /* Now turn off stdio if not tracing */
 356         if (new_tracelevel == 0)
 357                 trace_close(background);
 358
 359         /* Loop forever, listening and broadcasting.
 360          */
 361         for (;;) {
 362                 prev_clk = clk;
 363                 gettimeofday(&clk, 0);
 364                 if (prev_clk.tv_sec == clk.tv_sec
 365                     && prev_clk.tv_usec == clk.tv_usec+usec_fudge) {
 366                         /* Much of `routed` depends on time always advancing.
 367                          * On systems that do not guarantee that gettimeofday()
 368                          * produces unique timestamps even if called within
 369                          * a single tick, use trickery like that in classic
 370                          * BSD kernels.
 371                          */
 372                         clk.tv_usec += ++usec_fudge;
 373
 374                 } else {
 375                         usec_fudge = 0;
 376
 377                         timevalsub(&t2, &clk, &prev_clk);
 378                         if (t2.tv_sec < 0
 379                             || t2.tv_sec > wtime.tv_sec + 5) {
 380                                 /* Deal with time changes before other
 381                                  * housekeeping to keep everything straight.
 382                                  */
 383                                 dt = t2.tv_sec;
 384                                 if (dt > 0)
 385                                         dt -= wtime.tv_sec;
 386                                 trace_act("time changed by %d sec", (int)dt);
 387                                 epoch.tv_sec += dt;
 388                         }
 389                 }
 390                 timevalsub(&now, &clk, &epoch);
 391                 now_stale = now.tv_sec - STALE_TIME;
 392                 now_expire = now.tv_sec - EXPIRE_TIME;
 393                 now_garbage = now.tv_sec - GARBAGE_TIME;
 394
 395                 /* deal with signals that should affect tracing */
 396                 set_tracelevel();
 397
 398                 if (stopint != 0) {
 399                         rip_bcast(0);
 400                         rdisc_adv();
 401                         trace_off("exiting with signal %d", stopint);
 402                         exit(stopint | 128);
 403                 }
 404
 405                 /* look for new or dead interfaces */
 406                 timevalsub(&wtime, &ifinit_timer, &now);
 407                 if (wtime.tv_sec <= 0) {
 408                         wtime.tv_sec = 0;
 409                         ifinit();
 410                         rip_query();
 411                         continue;
 412                 }
 413
 414                 /* Check the kernel table occassionally for mysteriously
 415                  * evaporated routes
 416                  */
 417                 timevalsub(&t2, &flush_kern_timer, &now);
 418                 if (t2.tv_sec <= 0) {
 419                         flush_kern();
 420                         flush_kern_timer.tv_sec = (now.tv_sec
 421                                                    + CHECK_QUIET_INTERVAL);
 422                         continue;
 423                 }
 424                 if (timercmp(&t2, &wtime, <))
 425                         wtime = t2;
 426
 427                 /* If it is time, then broadcast our routes.
 428                  */
 429                 if (supplier || advertise_mhome) {
 430                         timevalsub(&t2, &next_bcast, &now);
 431                         if (t2.tv_sec <= 0) {
 432                                 /* Synchronize the aging and broadcast
 433                                  * timers to minimize awakenings
 434                                  */
 435                                 age(0);
 436
 437                                 rip_bcast(0);
 438
 439                                 /* It is desirable to send routing updates
 440                                  * regularly.  So schedule the next update
 441                                  * 30 seconds after the previous one was
 442                                  * scheduled, instead of 30 seconds after
 443                                  * the previous update was finished.
 444                                  * Even if we just started after discovering
 445                                  * a 2nd interface or were otherwise delayed,
 446                                  * pick a 30-second aniversary of the
 447                                  * original broadcast time.
 448                                  */
 449                                 n = 1 + (0-t2.tv_sec)/SUPPLY_INTERVAL;
 450                                 next_bcast.tv_sec += n*SUPPLY_INTERVAL;
 451
 452                                 continue;
 453                         }
 454
 455                         if (timercmp(&t2, &wtime, <))
 456                                 wtime = t2;
 457                 }
 458
 459                 /* If we need a flash update, either do it now or
 460                  * set the delay to end when it is time.
 461                  *
 462                  * If we are within MIN_WAITTIME seconds of a full update,
 463                  * do not bother.
 464                  */
 465                 if (need_flash
 466                     && supplier
 467                     && no_flash.tv_sec+MIN_WAITTIME < next_bcast.tv_sec) {
 468                         /* accurate to the millisecond */
 469                         if (!timercmp(&no_flash, &now, >))
 470                                 rip_bcast(1);
 471                         timevalsub(&t2, &no_flash, &now);
 472                         if (timercmp(&t2, &wtime, <))
 473                                 wtime = t2;
 474                 }
 475
 476                 /* trigger the main aging timer.
 477                  */
 478                 timevalsub(&t2, &age_timer, &now);
 479                 if (t2.tv_sec <= 0) {
 480                         age(0);
 481                         continue;
 482                 }
 483                 if (timercmp(&t2, &wtime, <))
 484                         wtime = t2;
 485
 486                 /* update the kernel routing table
 487                  */
 488                 timevalsub(&t2, &need_kern, &now);
 489                 if (t2.tv_sec <= 0) {
 490                         age(0);
 491                         continue;
 492                 }
 493                 if (timercmp(&t2, &wtime, <))
 494                         wtime = t2;
 495
 496                 /* take care of router discovery,
 497                  * but do it in the correct the millisecond
 498                  */
 499                 if (!timercmp(&rdisc_timer, &now, >)) {
 500                         rdisc_age(0);
 501                         continue;
 502                 }
 503                 timevalsub(&t2, &rdisc_timer, &now);
 504                 if (timercmp(&t2, &wtime, <))
 505                         wtime = t2;
 506
 507
 508                 /* wait for input or a timer to expire.
 509                  */
 510                 trace_flush();
 511                 if (ibitsp)
 512                         free(ibitsp);
 513                 ibitsp = (fd_set *)calloc(howmany(sock_max, NFDBITS),
 514                     sizeof(fd_mask));
 515                 if (ibitsp == NULL)
 516                         BADERR(1, "calloc");
 517                 memcpy(ibitsp, fdbitsp, howmany(sock_max, NFDBITS) *
 518                     sizeof(fd_mask));
 519                 n = select(sock_max, ibitsp, 0, 0, &wtime);
 520                 if (n <= 0) {
 521                         if (n < 0 && errno != EINTR && errno != EAGAIN)
 522                                 BADERR(1,"select");
 523                         continue;
 524                 }
 525
 526                 if (FD_ISSET(rt_sock, ibitsp)) {
 527                         read_rt();
 528                         n--;
 529                 }
 530                 if (rdisc_sock >= 0 && FD_ISSET(rdisc_sock, ibitsp)) {
 531                         read_d();
 532                         n--;
 533                 }
 534                 if (rip_sock >= 0 && FD_ISSET(rip_sock, ibitsp)) {
 535                         read_rip(rip_sock, 0);
 536                         n--;
 537                 }
 538
 539                 for (ifp = ifnet; n > 0 && 0 != ifp; ifp = ifp->int_next) {
 540                         if (ifp->int_rip_sock >= 0
 541                             && FD_ISSET(ifp->int_rip_sock, ibitsp)) {
 542                                 read_rip(ifp->int_rip_sock, ifp);
 543                                 n--;
 544                         }
 545                 }
 546         }
 547 }
 548
 549
 550 /* ARGSUSED */
 551 void
 552 sigalrm(int s UNUSED)
 553 {
 554         /* Historically, SIGALRM would cause the daemon to check for
 555          * new and broken interfaces.
 556          */
 557         ifinit_timer.tv_sec = now.tv_sec;
 558         trace_act("SIGALRM");
 559 }
 560
 561
 562 /* watch for fatal signals */
 563 void
 564 sigterm(int sig)
 565 {
 566         stopint = sig;
 567         (void)signal(sig, SIG_DFL);     /* catch it only once */
 568 }
 569
 570
 571 void
 572 fix_select(void)
 573 {
 574         struct interface *ifp;
 575
 576         sock_max = 0;
 577
 578         if (sock_max <= rt_sock)
 579                 sock_max = rt_sock + 1;
 580         if (rip_sock >= 0)
 581                 if (sock_max <= rip_sock)
 582                         sock_max = rip_sock + 1;
 583         for (ifp = ifnet; 0 != ifp; ifp = ifp->int_next) {
 584                 if (ifp->int_rip_sock >= 0)
 585                         if (sock_max <= ifp->int_rip_sock)
 586                                 sock_max = ifp->int_rip_sock + 1;
 587         }
 588         if (rdisc_sock >= 0)
 589                 if (sock_max <= rdisc_sock)
 590                         sock_max = rdisc_sock + 1;
 591
 592         if (fdbitsp)
 593                 free(fdbitsp);
 594         fdbitsp = (fd_set *)calloc(howmany(sock_max, NFDBITS),
 595             sizeof(fd_mask));
 596         if (fdbitsp == NULL)
 597                 BADERR(1, "calloc");
 598
 599         FD_SET(rt_sock, fdbitsp);
 600         if (rip_sock >= 0)
 601                 FD_SET(rip_sock, fdbitsp);
 602         for (ifp = ifnet; 0 != ifp; ifp = ifp->int_next) {
 603                 if (ifp->int_rip_sock >= 0)
 604                         FD_SET(ifp->int_rip_sock, fdbitsp);
 605         }
 606         if (rdisc_sock >= 0)
 607                 FD_SET(rdisc_sock, fdbitsp);
 608 }
 609
 610
 611 void
 612 fix_sock(int sock,
 613          const char *name)
 614 {
 615         int on;
 616 #define MIN_SOCKBUF (4*1024)
 617         static int rbuf;
 618
 619         if (fcntl(sock, F_SETFL, O_NONBLOCK) == -1)
 620                 logbad(1, "fcntl(%s) O_NONBLOCK: %s",
 621                        name, strerror(errno));
 622         on = 1;
 623         if (setsockopt(sock, SOL_SOCKET,SO_BROADCAST, &on,sizeof(on)) < 0)
 624                 msglog("setsockopt(%s,SO_BROADCAST): %s",
 625                        name, strerror(errno));
 626 #ifdef USE_PASSIFNAME
 627         on = 1;
 628         if (setsockopt(sock, SOL_SOCKET, SO_PASSIFNAME, &on,sizeof(on)) < 0)
 629                 msglog("setsockopt(%s,SO_PASSIFNAME): %s",
 630                        name, strerror(errno));
 631 #endif
 632
 633         if (rbuf >= MIN_SOCKBUF) {
 634                 if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
 635                                &rbuf, sizeof(rbuf)) < 0)
 636                         msglog("setsockopt(%s,SO_RCVBUF=%d): %s",
 637                                name, rbuf, strerror(errno));
 638         } else {
 639                 for (rbuf = 60*1024; ; rbuf -= 4096) {
 640                         if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
 641                                        &rbuf, sizeof(rbuf)) == 0) {
 642                                 trace_act("RCVBUF=%d", rbuf);
 643                                 break;
 644                         }
 645                         if (rbuf < MIN_SOCKBUF) {
 646                                 msglog("setsockopt(%s,SO_RCVBUF = %d): %s",
 647                                        name, rbuf, strerror(errno));
 648                                 break;
 649                         }
 650                 }
 651         }
 652 }
 653
 654
 655 /* get a rip socket
 656  */
 657 static int                              /* <0 or file descriptor */
 658 get_rip_sock(naddr addr,
 659              int serious)               /* 1=failure to bind is serious */
 660 {
 661         struct sockaddr_in rsin;
 662         unsigned char ttl;
 663         int s;
 664
 665
 666         if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
 667                 BADERR(1,"rip_sock = socket()");
 668
 669         memset(&rsin, 0, sizeof(rsin));
 670 #ifdef _HAVE_SIN_LEN
 671         rsin.sin_len = sizeof(rsin);
 672 #endif
 673         rsin.sin_family = AF_INET;
 674         rsin.sin_port = htons(RIP_PORT);
 675         rsin.sin_addr.s_addr = addr;
 676         if (bind(s, (struct sockaddr *)&rsin, sizeof(rsin)) < 0) {
 677                 if (serious)
 678                         BADERR(errno != EADDRINUSE, "bind(rip_sock)");
 679                 return -1;
 680         }
 681         fix_sock(s,"rip_sock");
 682
 683         ttl = 1;
 684         if (setsockopt(s, IPPROTO_IP, IP_MULTICAST_TTL,
 685                        &ttl, sizeof(ttl)) < 0)
 686                 DBGERR(1,"rip_sock setsockopt(IP_MULTICAST_TTL)");
 687
 688         return s;
 689 }
 690
 691
 692 /* turn off main RIP socket */
 693 void
 694 rip_off(void)
 695 {
 696         struct interface *ifp;
 697         naddr addr;
 698
 699
 700         if (rip_sock >= 0 && !mhome) {
 701                 trace_act("turn off RIP");
 702
 703                 (void)close(rip_sock);
 704                 rip_sock = -1;
 705
 706                 /* get non-broadcast sockets to listen to queries.
 707                  */
 708                 for (ifp = ifnet; ifp != 0; ifp = ifp->int_next) {
 709                         if (ifp->int_state & IS_REMOTE)
 710                                 continue;
 711                         if (ifp->int_rip_sock < 0) {
 712                                 addr = ((ifp->int_if_flags & IFF_POINTOPOINT)
 713                                         ? ifp->int_dstaddr
 714                                         : ifp->int_addr);
 715                                 ifp->int_rip_sock = get_rip_sock(addr, 0);
 716                         }
 717                 }
 718
 719                 fix_select();
 720
 721                 age(0);
 722         }
 723 }
 724
 725
 726 /* turn on RIP multicast input via an interface
 727  */
 728 static void
 729 rip_mcast_on(struct interface *ifp)
 730 {
 731         struct ip_mreq m;
 732
 733         if (!IS_RIP_IN_OFF(ifp->int_state)
 734             && (ifp->int_if_flags & IFF_MULTICAST)
 735 #ifdef MCAST_PPP_BUG
 736             && !(ifp->int_if_flags & IFF_POINTOPOINT)
 737 #endif
 738             && !(ifp->int_state & IS_ALIAS)) {
 739                 m.imr_multiaddr.s_addr = htonl(INADDR_RIP_GROUP);
 740 #ifdef MCAST_IFINDEX
 741                 m.imr_interface.s_addr = htonl(ifp->int_index);
 742 #else
 743                 m.imr_interface.s_addr = ((ifp->int_if_flags & IFF_POINTOPOINT)
 744                                           ? ifp->int_dstaddr
 745                                           : ifp->int_addr);
 746 #endif
 747                 if (setsockopt(rip_sock,IPPROTO_IP, IP_ADD_MEMBERSHIP,
 748                                &m, sizeof(m)) < 0)
 749                         LOGERR("setsockopt(IP_ADD_MEMBERSHIP RIP)");
 750         }
 751 }
 752
 753
 754 /* Prepare socket used for RIP.
 755  */
 756 void
 757 rip_on(struct interface *ifp)
 758 {
 759         /* If the main RIP socket is already alive, only start receiving
 760          * multicasts for this interface.
 761          */
 762         if (rip_sock >= 0) {
 763                 if (ifp != 0)
 764                         rip_mcast_on(ifp);
 765                 return;
 766         }
 767
 768         /* If the main RIP socket is off and it makes sense to turn it on,
 769          * then turn it on for all of the interfaces.
 770          * It makes sense if either router discovery is off, or if
 771          * router discover is on and at most one interface is doing RIP.
 772          */
 773         if (rip_interfaces > 0 && (!rdisc_ok || rip_interfaces > 1)) {
 774                 trace_act("turn on RIP");
 775
 776                 /* Close all of the query sockets so that we can open
 777                  * the main socket.  SO_REUSEPORT is not a solution,
 778                  * since that would let two daemons bind to the broadcast
 779                  * socket.
 780                  */
 781                 for (ifp = ifnet; ifp != 0; ifp = ifp->int_next) {
 782                         if (ifp->int_rip_sock >= 0) {
 783                                 (void)close(ifp->int_rip_sock);
 784                                 ifp->int_rip_sock = -1;
 785                         }
 786                 }
 787
 788                 rip_sock = get_rip_sock(INADDR_ANY, 1);
 789                 rip_sock_mcast = 0;
 790
 791                 /* Do not advertise anything until we have heard something
 792                  */
 793                 if (next_bcast.tv_sec < now.tv_sec+MIN_WAITTIME)
 794                         next_bcast.tv_sec = now.tv_sec+MIN_WAITTIME;
 795
 796                 for (ifp = ifnet; ifp != 0; ifp = ifp->int_next) {
 797                         ifp->int_query_time = NEVER;
 798                         rip_mcast_on(ifp);
 799                 }
 800                 ifinit_timer.tv_sec = now.tv_sec;
 801
 802         } else if (ifp != 0
 803                    && !(ifp->int_state & IS_REMOTE)
 804                    && ifp->int_rip_sock < 0) {
 805                 /* RIP is off, so ensure there are sockets on which
 806                  * to listen for queries.
 807                  */
 808                 ifp->int_rip_sock = get_rip_sock(ifp->int_addr, 0);
 809         }
 810
 811         fix_select();
 812 }
 813
 814
 815 /* die if malloc(3) fails
 816  */
 817 void *
 818 rtmalloc(size_t size,
 819          const char *msg)
 820 {
 821         void *p = malloc(size);
 822         if (p == 0)
 823                 logbad(1,"malloc(%lu) failed in %s", (u_long)size, msg);
 824         return p;
 825 }
 826
 827
 828 /* get a random instant in an interval
 829  */
 830 void
 831 intvl_random(struct timeval *tp,        /* put value here */
 832              u_long lo,                 /* value is after this second */
 833              u_long hi)                 /* and before this */
 834 {
 835         tp->tv_sec = (time_t)(hi == lo
 836                               ? lo
 837                               : (lo + arc4random() % ((hi - lo))));
 838         tp->tv_usec = arc4random() % 1000000;
 839 }
 840
 841
 842 void
 843 timevaladd(struct timeval *t1,
 844            struct timeval *t2)
 845 {
 846
 847         t1->tv_sec += t2->tv_sec;
 848         if ((t1->tv_usec += t2->tv_usec) >= 1000000) {
 849                 t1->tv_sec++;
 850                 t1->tv_usec -= 1000000;
 851         }
 852 }
 853
 854
 855 /* t1 = t2 - t3
 856  */
 857 static void
 858 timevalsub(struct timeval *t1,
 859            struct timeval *t2,
 860            struct timeval *t3)
 861 {
 862         t1->tv_sec = t2->tv_sec - t3->tv_sec;
 863         if ((t1->tv_usec = t2->tv_usec - t3->tv_usec) < 0) {
 864                 t1->tv_sec--;
 865                 t1->tv_usec += 1000000;
 866         }
 867 }
 868
 869
 870 /* put a message into the system log
 871  */
 872 void
 873 msglog(const char *p, ...)
 874 {
 875         va_list args;
 876
 877         trace_flush();
 878
 879         va_start(args, p);
 880         vsyslog(LOG_ERR, p, args);
 881         va_end(args);
 882
 883         if (ftrace != 0) {
 884                 if (ftrace == stdout)
 885                         (void)fputs("routed: ", ftrace);
 886                 va_start(args, p);
 887                 (void)vfprintf(ftrace, p, args);
 888                 va_end(args);
 889                 (void)fputc('\n', ftrace);
 890         }
 891 }
 892
 893
 894 /* Put a message about a bad system into the system log if
 895  * we have not complained about it recently.
 896  *
 897  * It is desirable to complain about all bad systems, but not too often.
 898  * In the worst case, it is not practical to keep track of all bad systems.
 899  * For example, there can be many systems with the wrong password.
 900  */
 901 void
 902 msglim(struct msg_limit *lim, naddr addr, const char *p, ...)
 903 {
 904         va_list args;
 905         int i;
 906         struct msg_sub *ms1, *ms;
 907         const char *p1;
 908
 909         /* look for the oldest slot in the table
 910          * or the slot for the bad router.
 911          */
 912         ms = ms1 = lim->subs;
 913         for (i = MSG_SUBJECT_N; ; i--, ms1++) {
 914                 if (i == 0) {
 915                         /* Reuse a slot at most once every 10 minutes.
 916                          */
 917                         if (lim->reuse > now.tv_sec) {
 918                                 ms = 0;
 919                         } else {
 920                                 ms = ms1;
 921                                 lim->reuse = now.tv_sec + 10*60;
 922                         }
 923                         break;
 924                 }
 925                 if (ms->addr == addr) {
 926                         /* Repeat a complaint about a given system at
 927                          * most once an hour.
 928                          */
 929                         if (ms->until > now.tv_sec)
 930                                 ms = 0;
 931                         break;
 932                 }
 933                 if (ms->until < ms1->until)
 934                         ms = ms1;
 935         }
 936         if (ms != 0) {
 937                 ms->addr = addr;
 938                 ms->until = now.tv_sec + 60*60; /* 60 minutes */
 939
 940                 trace_flush();
 941                 for (p1 = p; *p1 == ' '; p1++)
 942                         continue;
 943                 va_start(args, p);
 944                 vsyslog(LOG_ERR, p1, args);
 945                 va_end(args);
 946         }
 947
 948         /* always display the message if tracing */
 949         if (ftrace != 0) {
 950                 va_start(args, p);
 951                 (void)vfprintf(ftrace, p, args);
 952                 (void)fputc('\n', ftrace);
 953                 va_end(args);
 954         }
 955 }
 956
 957
 958 void
 959 logbad(int dump, const char *p, ...)
 960 {
 961         va_list args;
 962
 963         trace_flush();
 964
 965         va_start(args, p);
 966         vsyslog(LOG_ERR, p, args);
 967         va_end(args);
 968
 969         (void)fputs("routed: ", stderr);
 970         va_start(args, p);
 971         (void)vfprintf(stderr, p, args);
 972         va_end(args);
 973         (void)fputs("; giving up\n",stderr);
 974         (void)fflush(stderr);
 975
 976         if (dump)
 977                 abort();
 978         exit(1);
 979 }