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 #ident "$FreeBSD: src/sbin/routed/main.c,v 1.11.2.1 2000/08/14 17:00:03 sheldonh Exp $"
  57
  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  fdbits;
  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 ibits;
 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_ODELAY, 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         gethostname(myname, sizeof(myname)-1);
 139         gethost(myname, &myaddr);
 140
 141         while ((n = getopt(argc, argv, "sqdghmpAtvT: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 2.22");
 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 [-sqdghmpAtv] [-T tracefile]"
 246                        " [-F net[,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         mypid = getpid();
 301         srandom((int)(clk.tv_sec ^ clk.tv_usec ^ mypid));
 302
 303         /* prepare socket connected to the kernel.
 304          */
 305         rt_sock = socket(AF_ROUTE, SOCK_RAW, 0);
 306         if (rt_sock < 0)
 307                 BADERR(1,"rt_sock = socket()");
 308         if (fcntl(rt_sock, F_SETFL, O_NONBLOCK) == -1)
 309                 logbad(1, "fcntl(rt_sock) O_NONBLOCK: %s", strerror(errno));
 310         off = 0;
 311         if (setsockopt(rt_sock, SOL_SOCKET,SO_USELOOPBACK,
 312                        &off,sizeof(off)) < 0)
 313                 LOGERR("setsockopt(SO_USELOOPBACK,0)");
 314
 315         fix_select();
 316
 317
 318         if (tracename != 0) {
 319                 strncpy(inittracename, tracename, sizeof(inittracename)-1);
 320                 set_tracefile(inittracename, "%s", -1);
 321         } else {
 322                 tracelevel_msg("%s", -1);   /* turn on tracing to stdio */
 323         }
 324
 325         bufinit();
 326
 327         /* initialize radix tree */
 328         rtinit();
 329
 330         /* Pick a random part of the second for our output to minimize
 331          * collisions.
 332          *
 333          * Start broadcasting after hearing from other routers, and
 334          * at a random time so a bunch of systems do not get synchronized
 335          * after a power failure.
 336          */
 337         intvl_random(&next_bcast, EPOCH+MIN_WAITTIME, EPOCH+SUPPLY_INTERVAL);
 338         age_timer.tv_usec = next_bcast.tv_usec;
 339         age_timer.tv_sec = EPOCH+MIN_WAITTIME;
 340         rdisc_timer = next_bcast;
 341         ifinit_timer.tv_usec = next_bcast.tv_usec;
 342
 343         /* Collect an initial view of the world by checking the interface
 344          * configuration and the kludge file.
 345          */
 346         gwkludge();
 347         ifinit();
 348
 349         /* Ask for routes */
 350         rip_query();
 351         rdisc_sol();
 352
 353         /* Now turn off stdio if not tracing */
 354         if (new_tracelevel == 0)
 355                 trace_close(background);
 356
 357         /* Loop forever, listening and broadcasting.
 358          */
 359         for (;;) {
 360                 prev_clk = clk;
 361                 gettimeofday(&clk, 0);
 362                 if (prev_clk.tv_sec == clk.tv_sec
 363                     && prev_clk.tv_usec == clk.tv_usec+usec_fudge) {
 364                         /* Much of `routed` depends on time always advancing.
 365                          * On systems that do not guarantee that gettimeofday()
 366                          * produces unique timestamps even if called within
 367                          * a single tick, use trickery like that in classic
 368                          * BSD kernels.
 369                          */
 370                         clk.tv_usec += ++usec_fudge;
 371
 372                 } else {
 373                         usec_fudge = 0;
 374
 375                         timevalsub(&t2, &clk, &prev_clk);
 376                         if (t2.tv_sec < 0
 377                             || t2.tv_sec > wtime.tv_sec + 5) {
 378                                 /* Deal with time changes before other
 379                                  * housekeeping to keep everything straight.
 380                                  */
 381                                 dt = t2.tv_sec;
 382                                 if (dt > 0)
 383                                         dt -= wtime.tv_sec;
 384                                 trace_act("time changed by %d sec", (int)dt);
 385                                 epoch.tv_sec += dt;
 386                         }
 387                 }
 388                 timevalsub(&now, &clk, &epoch);
 389                 now_stale = now.tv_sec - STALE_TIME;
 390                 now_expire = now.tv_sec - EXPIRE_TIME;
 391                 now_garbage = now.tv_sec - GARBAGE_TIME;
 392
 393                 /* deal with signals that should affect tracing */
 394                 set_tracelevel();
 395
 396                 if (stopint != 0) {
 397                         rip_bcast(0);
 398                         rdisc_adv();
 399                         trace_off("exiting with signal %d", stopint);
 400                         exit(stopint | 128);
 401                 }
 402
 403                 /* look for new or dead interfaces */
 404                 timevalsub(&wtime, &ifinit_timer, &now);
 405                 if (wtime.tv_sec <= 0) {
 406                         wtime.tv_sec = 0;
 407                         ifinit();
 408                         rip_query();
 409                         continue;
 410                 }
 411
 412                 /* Check the kernel table occassionally for mysteriously
 413                  * evaporated routes
 414                  */
 415                 timevalsub(&t2, &flush_kern_timer, &now);
 416                 if (t2.tv_sec <= 0) {
 417                         flush_kern();
 418                         flush_kern_timer.tv_sec = (now.tv_sec
 419                                                    + CHECK_QUIET_INTERVAL);
 420                         continue;
 421                 }
 422                 if (timercmp(&t2, &wtime, <))
 423                         wtime = t2;
 424
 425                 /* If it is time, then broadcast our routes.
 426                  */
 427                 if (supplier || advertise_mhome) {
 428                         timevalsub(&t2, &next_bcast, &now);
 429                         if (t2.tv_sec <= 0) {
 430                                 /* Synchronize the aging and broadcast
 431                                  * timers to minimize awakenings
 432                                  */
 433                                 age(0);
 434
 435                                 rip_bcast(0);
 436
 437                                 /* It is desirable to send routing updates
 438                                  * regularly.  So schedule the next update
 439                                  * 30 seconds after the previous one was
 440                                  * scheduled, instead of 30 seconds after
 441                                  * the previous update was finished.
 442                                  * Even if we just started after discovering
 443                                  * a 2nd interface or were otherwise delayed,
 444                                  * pick a 30-second aniversary of the
 445                                  * original broadcast time.
 446                                  */
 447                                 n = 1 + (0-t2.tv_sec)/SUPPLY_INTERVAL;
 448                                 next_bcast.tv_sec += n*SUPPLY_INTERVAL;
 449
 450                                 continue;
 451                         }
 452
 453                         if (timercmp(&t2, &wtime, <))
 454                                 wtime = t2;
 455                 }
 456
 457                 /* If we need a flash update, either do it now or
 458                  * set the delay to end when it is time.
 459                  *
 460                  * If we are within MIN_WAITTIME seconds of a full update,
 461                  * do not bother.
 462                  */
 463                 if (need_flash
 464                     && supplier
 465                     && no_flash.tv_sec+MIN_WAITTIME < next_bcast.tv_sec) {
 466                         /* accurate to the millisecond */
 467                         if (!timercmp(&no_flash, &now, >))
 468                                 rip_bcast(1);
 469                         timevalsub(&t2, &no_flash, &now);
 470                         if (timercmp(&t2, &wtime, <))
 471                                 wtime = t2;
 472                 }
 473
 474                 /* trigger the main aging timer.
 475                  */
 476                 timevalsub(&t2, &age_timer, &now);
 477                 if (t2.tv_sec <= 0) {
 478                         age(0);
 479                         continue;
 480                 }
 481                 if (timercmp(&t2, &wtime, <))
 482                         wtime = t2;
 483
 484                 /* update the kernel routing table
 485                  */
 486                 timevalsub(&t2, &need_kern, &now);
 487                 if (t2.tv_sec <= 0) {
 488                         age(0);
 489                         continue;
 490                 }
 491                 if (timercmp(&t2, &wtime, <))
 492                         wtime = t2;
 493
 494                 /* take care of router discovery,
 495                  * but do it in the correct the millisecond
 496                  */
 497                 if (!timercmp(&rdisc_timer, &now, >)) {
 498                         rdisc_age(0);
 499                         continue;
 500                 }
 501                 timevalsub(&t2, &rdisc_timer, &now);
 502                 if (timercmp(&t2, &wtime, <))
 503                         wtime = t2;
 504
 505
 506                 /* wait for input or a timer to expire.
 507                  */
 508                 trace_flush();
 509                 ibits = fdbits;
 510                 n = select(sock_max, &ibits, 0, 0, &wtime);
 511                 if (n <= 0) {
 512                         if (n < 0 && errno != EINTR && errno != EAGAIN)
 513                                 BADERR(1,"select");
 514                         continue;
 515                 }
 516
 517                 if (FD_ISSET(rt_sock, &ibits)) {
 518                         read_rt();
 519                         n--;
 520                 }
 521                 if (rdisc_sock >= 0 && FD_ISSET(rdisc_sock, &ibits)) {
 522                         read_d();
 523                         n--;
 524                 }
 525                 if (rip_sock >= 0 && FD_ISSET(rip_sock, &ibits)) {
 526                         read_rip(rip_sock, 0);
 527                         n--;
 528                 }
 529
 530                 for (ifp = ifnet; n > 0 && 0 != ifp; ifp = ifp->int_next) {
 531                         if (ifp->int_rip_sock >= 0
 532                             && FD_ISSET(ifp->int_rip_sock, &ibits)) {
 533                                 read_rip(ifp->int_rip_sock, ifp);
 534                                 n--;
 535                         }
 536                 }
 537         }
 538 }
 539
 540
 541 /* ARGSUSED */
 542 void
 543 sigalrm(int s UNUSED)
 544 {
 545         /* Historically, SIGALRM would cause the daemon to check for
 546          * new and broken interfaces.
 547          */
 548         ifinit_timer.tv_sec = now.tv_sec;
 549         trace_act("SIGALRM");
 550 }
 551
 552
 553 /* watch for fatal signals */
 554 void
 555 sigterm(int sig)
 556 {
 557         stopint = sig;
 558         signal(sig, SIG_DFL);   /* catch it only once */
 559 }
 560
 561
 562 void
 563 fix_select(void)
 564 {
 565         struct interface *ifp;
 566
 567
 568         FD_ZERO(&fdbits);
 569         sock_max = 0;
 570
 571         FD_SET(rt_sock, &fdbits);
 572         if (sock_max <= rt_sock)
 573                 sock_max = rt_sock+1;
 574         if (rip_sock >= 0) {
 575                 FD_SET(rip_sock, &fdbits);
 576                 if (sock_max <= rip_sock)
 577                         sock_max = rip_sock+1;
 578         }
 579         for (ifp = ifnet; 0 != ifp; ifp = ifp->int_next) {
 580                 if (ifp->int_rip_sock >= 0) {
 581                         FD_SET(ifp->int_rip_sock, &fdbits);
 582                         if (sock_max <= ifp->int_rip_sock)
 583                                 sock_max = ifp->int_rip_sock+1;
 584                 }
 585         }
 586         if (rdisc_sock >= 0) {
 587                 FD_SET(rdisc_sock, &fdbits);
 588                 if (sock_max <= rdisc_sock)
 589                         sock_max = rdisc_sock+1;
 590         }
 591 }
 592
 593
 594 void
 595 fix_sock(int sock,
 596          const char *name)
 597 {
 598         int on;
 599 #define MIN_SOCKBUF (4*1024)
 600         static int rbuf;
 601
 602         if (fcntl(sock, F_SETFL, O_NONBLOCK) == -1)
 603                 logbad(1, "fcntl(%s) O_NONBLOCK: %s",
 604                        name, strerror(errno));
 605         on = 1;
 606         if (setsockopt(sock, SOL_SOCKET,SO_BROADCAST, &on,sizeof(on)) < 0)
 607                 msglog("setsockopt(%s,SO_BROADCAST): %s",
 608                        name, strerror(errno));
 609 #ifdef USE_PASSIFNAME
 610         on = 1;
 611         if (setsockopt(sock, SOL_SOCKET, SO_PASSIFNAME, &on,sizeof(on)) < 0)
 612                 msglog("setsockopt(%s,SO_PASSIFNAME): %s",
 613                        name, strerror(errno));
 614 #endif
 615
 616         if (rbuf >= MIN_SOCKBUF) {
 617                 if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
 618                                &rbuf, sizeof(rbuf)) < 0)
 619                         msglog("setsockopt(%s,SO_RCVBUF=%d): %s",
 620                                name, rbuf, strerror(errno));
 621         } else {
 622                 for (rbuf = 60*1024; ; rbuf -= 4096) {
 623                         if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
 624                                        &rbuf, sizeof(rbuf)) == 0) {
 625                                 trace_act("RCVBUF=%d", rbuf);
 626                                 break;
 627                         }
 628                         if (rbuf < MIN_SOCKBUF) {
 629                                 msglog("setsockopt(%s,SO_RCVBUF = %d): %s",
 630                                        name, rbuf, strerror(errno));
 631                                 break;
 632                         }
 633                 }
 634         }
 635 }
 636
 637
 638 /* get a rip socket
 639  */
 640 static int                              /* <0 or file descriptor */
 641 get_rip_sock(naddr addr,
 642              int serious)               /* 1=failure to bind is serious */
 643 {
 644         struct sockaddr_in in;
 645         unsigned char ttl;
 646         int s;
 647
 648
 649         if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
 650                 BADERR(1,"rip_sock = socket()");
 651
 652         memset(&in, 0, sizeof(in));
 653 #ifdef _HAVE_SIN_LEN
 654         in.sin_len = sizeof(in);
 655 #endif
 656         in.sin_family = AF_INET;
 657         in.sin_port = htons(RIP_PORT);
 658         in.sin_addr.s_addr = addr;
 659         if (bind(s, (struct sockaddr *)&in, sizeof(in)) < 0) {
 660                 if (serious)
 661                         BADERR(errno != EADDRINUSE, "bind(rip_sock)");
 662                 return -1;
 663         }
 664         fix_sock(s,"rip_sock");
 665
 666         ttl = 1;
 667         if (setsockopt(s, IPPROTO_IP, IP_MULTICAST_TTL,
 668                        &ttl, sizeof(ttl)) < 0)
 669                 DBGERR(1,"rip_sock setsockopt(IP_MULTICAST_TTL)");
 670
 671         return s;
 672 }
 673
 674
 675 /* turn off main RIP socket */
 676 void
 677 rip_off(void)
 678 {
 679         struct interface *ifp;
 680         naddr addr;
 681
 682
 683         if (rip_sock >= 0 && !mhome) {
 684                 trace_act("turn off RIP");
 685
 686                 close(rip_sock);
 687                 rip_sock = -1;
 688
 689                 /* get non-broadcast sockets to listen to queries.
 690                  */
 691                 for (ifp = ifnet; ifp != 0; ifp = ifp->int_next) {
 692                         if (ifp->int_state & IS_REMOTE)
 693                                 continue;
 694                         if (ifp->int_rip_sock < 0) {
 695                                 addr = ((ifp->int_if_flags & IFF_POINTOPOINT)
 696                                         ? ifp->int_dstaddr
 697                                         : ifp->int_addr);
 698                                 ifp->int_rip_sock = get_rip_sock(addr, 0);
 699                         }
 700                 }
 701
 702                 fix_select();
 703
 704                 age(0);
 705         }
 706 }
 707
 708
 709 /* turn on RIP multicast input via an interface
 710  */
 711 static void
 712 rip_mcast_on(struct interface *ifp)
 713 {
 714         struct ip_mreq m;
 715
 716         if (!IS_RIP_IN_OFF(ifp->int_state)
 717             && (ifp->int_if_flags & IFF_MULTICAST)
 718 #ifdef MCAST_PPP_BUG
 719             && !(ifp->int_if_flags & IFF_POINTOPOINT)
 720 #endif
 721             && !(ifp->int_state & IS_ALIAS)) {
 722                 m.imr_multiaddr.s_addr = htonl(INADDR_RIP_GROUP);
 723                 m.imr_interface.s_addr = ((ifp->int_if_flags & IFF_POINTOPOINT)
 724                                           ? ifp->int_dstaddr
 725                                           : ifp->int_addr);
 726                 if (setsockopt(rip_sock,IPPROTO_IP, IP_ADD_MEMBERSHIP,
 727                                &m, sizeof(m)) < 0)
 728                         LOGERR("setsockopt(IP_ADD_MEMBERSHIP RIP)");
 729         }
 730 }
 731
 732
 733 /* Prepare socket used for RIP.
 734  */
 735 void
 736 rip_on(struct interface *ifp)
 737 {
 738         /* If the main RIP socket is already alive, only start receiving
 739          * multicasts for this interface.
 740          */
 741         if (rip_sock >= 0) {
 742                 if (ifp != 0)
 743                         rip_mcast_on(ifp);
 744                 return;
 745         }
 746
 747         /* If the main RIP socket is off and it makes sense to turn it on,
 748          * then turn it on for all of the interfaces.
 749          * It makes sense if either router discovery is off, or if
 750          * router discover is on and at most one interface is doing RIP.
 751          */
 752         if (rip_interfaces > 0 && (!rdisc_ok || rip_interfaces > 1)) {
 753                 trace_act("turn on RIP");
 754
 755                 /* Close all of the query sockets so that we can open
 756                  * the main socket.  SO_REUSEPORT is not a solution,
 757                  * since that would let two daemons bind to the broadcast
 758                  * socket.
 759                  */
 760                 for (ifp = ifnet; ifp != 0; ifp = ifp->int_next) {
 761                         if (ifp->int_rip_sock >= 0) {
 762                                 close(ifp->int_rip_sock);
 763                                 ifp->int_rip_sock = -1;
 764                         }
 765                 }
 766
 767                 rip_sock = get_rip_sock(INADDR_ANY, 1);
 768                 rip_sock_mcast = 0;
 769
 770                 /* Do not advertise anything until we have heard something
 771                  */
 772                 if (next_bcast.tv_sec < now.tv_sec+MIN_WAITTIME)
 773                         next_bcast.tv_sec = now.tv_sec+MIN_WAITTIME;
 774
 775                 for (ifp = ifnet; ifp != 0; ifp = ifp->int_next) {
 776                         ifp->int_query_time = NEVER;
 777                         rip_mcast_on(ifp);
 778                 }
 779                 ifinit_timer.tv_sec = now.tv_sec;
 780
 781         } else if (ifp != 0
 782                    && !(ifp->int_state & IS_REMOTE)
 783                    && ifp->int_rip_sock < 0) {
 784                 /* RIP is off, so ensure there are sockets on which
 785                  * to listen for queries.
 786                  */
 787                 ifp->int_rip_sock = get_rip_sock(ifp->int_addr, 0);
 788         }
 789
 790         fix_select();
 791 }
 792
 793
 794 /* die if malloc(3) fails
 795  */
 796 void *
 797 rtmalloc(size_t size,
 798          const char *msg)
 799 {
 800         void *p = malloc(size);
 801         if (p == 0)
 802                 logbad(1,"malloc(%lu) failed in %s", (u_long)size, msg);
 803         return p;
 804 }
 805
 806
 807 /* get a random instant in an interval
 808  */
 809 void
 810 intvl_random(struct timeval *tp,        /* put value here */
 811              u_long lo,                 /* value is after this second */
 812              u_long hi)                 /* and before this */
 813 {
 814         tp->tv_sec = (time_t)(hi == lo
 815                               ? lo
 816                               : (lo + random() % ((hi - lo))));
 817         tp->tv_usec = random() % 1000000;
 818 }
 819
 820
 821 void
 822 timevaladd(struct timeval *t1,
 823            struct timeval *t2)
 824 {
 825
 826         t1->tv_sec += t2->tv_sec;
 827         if ((t1->tv_usec += t2->tv_usec) >= 1000000) {
 828                 t1->tv_sec++;
 829                 t1->tv_usec -= 1000000;
 830         }
 831 }
 832
 833
 834 /* t1 = t2 - t3
 835  */
 836 static void
 837 timevalsub(struct timeval *t1,
 838            struct timeval *t2,
 839            struct timeval *t3)
 840 {
 841         t1->tv_sec = t2->tv_sec - t3->tv_sec;
 842         if ((t1->tv_usec = t2->tv_usec - t3->tv_usec) < 0) {
 843                 t1->tv_sec--;
 844                 t1->tv_usec += 1000000;
 845         }
 846 }
 847
 848
 849 /* put a message into the system log
 850  */
 851 void
 852 msglog(const char *p, ...)
 853 {
 854         va_list args;
 855
 856         trace_flush();
 857
 858         va_start(args, p);
 859         vsyslog(LOG_ERR, p, args);
 860
 861         if (ftrace != 0) {
 862                 if (ftrace == stdout)
 863                         fputs("routed: ", ftrace);
 864                 vfprintf(ftrace, p, args);
 865                 fputc('\n', ftrace);
 866         }
 867 }
 868
 869
 870 /* Put a message about a bad system into the system log if
 871  * we have not complained about it recently.
 872  *
 873  * It is desirable to complain about all bad systems, but not too often.
 874  * In the worst case, it is not practical to keep track of all bad systems.
 875  * For example, there can be many systems with the wrong password.
 876  */
 877 void
 878 msglim(struct msg_limit *lim, naddr addr, const char *p, ...)
 879 {
 880         va_list args;
 881         int i;
 882         struct msg_sub *ms1, *ms;
 883         const char *p1;
 884
 885         va_start(args, p);
 886
 887         /* look for the oldest slot in the table
 888          * or the slot for the bad router.
 889          */
 890         ms = ms1 = lim->subs;
 891         for (i = MSG_SUBJECT_N; ; i--, ms1++) {
 892                 if (i == 0) {
 893                         /* Reuse a slot at most once every 10 minutes.
 894                          */
 895                         if (lim->reuse > now.tv_sec) {
 896                                 ms = 0;
 897                         } else {
 898                                 ms = ms1;
 899                                 lim->reuse = now.tv_sec + 10*60;
 900                         }
 901                         break;
 902                 }
 903                 if (ms->addr == addr) {
 904                         /* Repeat a complaint about a given system at
 905                          * most once an hour.
 906                          */
 907                         if (ms->until > now.tv_sec)
 908                                 ms = 0;
 909                         break;
 910                 }
 911                 if (ms->until < ms1->until)
 912                         ms = ms1;
 913         }
 914         if (ms != 0) {
 915                 ms->addr = addr;
 916                 ms->until = now.tv_sec + 60*60; /* 60 minutes */
 917
 918                 trace_flush();
 919                 for (p1 = p; *p1 == ' '; p1++)
 920                         continue;
 921                 vsyslog(LOG_ERR, p1, args);
 922         }
 923
 924         /* always display the message if tracing */
 925         if (ftrace != 0) {
 926                 vfprintf(ftrace, p, args);
 927                 fputc('\n', ftrace);
 928         }
 929 }
 930
 931
 932 void
 933 logbad(int dump, const char *p, ...)
 934 {
 935         va_list args;
 936
 937         trace_flush();
 938
 939         va_start(args, p);
 940         vsyslog(LOG_ERR, p, args);
 941
 942         fputs("routed: ", stderr);
 943         vfprintf(stderr, p, args);
 944         fputs("; giving up\n",stderr);
 945         fflush(stderr);
 946
 947         if (dump)
 948                 abort();
 949         exit(1);
 950 }