sbin/routed/main.c

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