usr.sbin/rtadvd/config.c

   1 /*      $KAME: config.c,v 1.37 2001/05/25 07:34:00 itojun Exp $ */
   2
   3 /*
   4  * Copyright (C) 1998 WIDE Project.
   5  * 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 project 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 PROJECT 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 PROJECT OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  *
  31  * $FreeBSD: src/usr.sbin/rtadvd/config.c,v 1.3.2.5 2003/04/22 09:40:57 suz Exp $
  32  * $DragonFly: src/usr.sbin/rtadvd/config.c,v 1.6 2005/12/05 00:56:37 swildner Exp $
  33  */
  34
  35 #include <sys/param.h>
  36 #include <sys/ioctl.h>
  37 #include <sys/socket.h>
  38 #include <sys/time.h>
  39 #include <sys/sysctl.h>
  40
  41 #include <net/if.h>
  42 #if defined(__DragonFly__)
  43 #include <net/if_var.h>
  44 #endif /* __DragonFly__  */
  45 #include <net/route.h>
  46 #include <net/if_dl.h>
  47
  48 #include <netinet/in.h>
  49 #include <netinet/in_var.h>
  50 #include <netinet/ip6.h>
  51 #include <netinet6/ip6_var.h>
  52 #include <netinet/icmp6.h>
  53 #ifdef MIP6
  54 #include <netinet6/mip6.h>
  55 #endif
  56
  57 #include <arpa/inet.h>
  58
  59 #include <stdio.h>
  60 #include <syslog.h>
  61 #include <errno.h>
  62 #include <string.h>
  63 #include <stdlib.h>
  64 #if defined(__NetBSD__) || defined(__OpenBSD__)
  65 #include <search.h>
  66 #endif
  67 #include <unistd.h>
  68 #include <ifaddrs.h>
  69
  70 #include "rtadvd.h"
  71 #include "advcap.h"
  72 #include "timer.h"
  73 #include "if.h"
  74 #include "config.h"
  75
  76 static time_t prefix_timo = (60 * 120); /* 2 hours.
  77                                          * XXX: should be configurable. */
  78 extern struct rainfo *ralist;
  79
  80 static struct rtadvd_timer *prefix_timeout(void *);
  81 static void makeentry(char *, size_t, int, char *, int);
  82 static void get_prefix(struct rainfo *);
  83 static int getinet6sysctl(int);
  84
  85 void
  86 getconfig(char *intface)
  87 {
  88         int stat, pfxs, i;
  89         char tbuf[BUFSIZ];
  90         struct rainfo *tmp;
  91         long val;
  92         long long val64;
  93         char buf[BUFSIZ];
  94         char *bp = buf;
  95         char *addr;
  96         static int forwarding = -1;
  97
  98 #define MUSTHAVE(var, cap)      \
  99     do {                                                                \
 100         int t;                                                          \
 101         if ((t = agetnum(cap)) < 0) {                                   \
 102                 fprintf(stderr, "rtadvd: need %s for interface %s\n",   \
 103                         cap, intface);                                  \
 104                 exit(1);                                                \
 105         }                                                               \
 106         var = t;                                                        \
 107      } while (0)
 108 #define MAYHAVE(var, cap, def)  \
 109      do {                                                               \
 110         if ((var = agetnum(cap)) < 0)                                   \
 111                 var = def;                                              \
 112      } while (0)
 113
 114         if ((stat = agetent(tbuf, intface)) <= 0) {
 115                 memset(tbuf, 0, sizeof(tbuf));
 116                 syslog(LOG_INFO,
 117                        "<%s> %s isn't defined in the configuration file"
 118                        " or the configuration file doesn't exist."
 119                        " Treat it as default",
 120                         __func__, intface);
 121         }
 122
 123         tmp = (struct rainfo *)malloc(sizeof(*ralist));
 124         memset(tmp, 0, sizeof(*tmp));
 125         tmp->prefix.next = tmp->prefix.prev = &tmp->prefix;
 126         tmp->route.next = tmp->route.prev = &tmp->route;
 127
 128         /* check if we are allowed to forward packets (if not determined) */
 129         if (forwarding < 0) {
 130                 if ((forwarding = getinet6sysctl(IPV6CTL_FORWARDING)) < 0)
 131                         exit(1);
 132         }
 133
 134         /* get interface information */
 135         if (agetflag("nolladdr"))
 136                 tmp->advlinkopt = 0;
 137         else
 138                 tmp->advlinkopt = 1;
 139         if (tmp->advlinkopt) {
 140                 if ((tmp->sdl = if_nametosdl(intface)) == NULL) {
 141                         syslog(LOG_ERR,
 142                                "<%s> can't get information of %s",
 143                                __func__, intface);
 144                         exit(1);
 145                 }
 146                 tmp->ifindex = tmp->sdl->sdl_index;
 147         } else
 148                 tmp->ifindex = if_nametoindex(intface);
 149         strncpy(tmp->ifname, intface, sizeof(tmp->ifname));
 150         if ((tmp->phymtu = if_getmtu(intface)) == 0) {
 151                 tmp->phymtu = IPV6_MMTU;
 152                 syslog(LOG_WARNING,
 153                        "<%s> can't get interface mtu of %s. Treat as %d",
 154                        __func__, intface, IPV6_MMTU);
 155         }
 156
 157         /*
 158          * set router configuration variables.
 159          */
 160         MAYHAVE(val, "maxinterval", DEF_MAXRTRADVINTERVAL);
 161         if (val < MIN_MAXINTERVAL || val > MAX_MAXINTERVAL) {
 162                 syslog(LOG_ERR,
 163                        "<%s> maxinterval must be between %e and %u",
 164                        __func__, MIN_MAXINTERVAL, MAX_MAXINTERVAL);
 165                 exit(1);
 166         }
 167         tmp->maxinterval = (u_int)val;
 168         MAYHAVE(val, "mininterval", tmp->maxinterval/3);
 169         if (val < MIN_MININTERVAL || val > (tmp->maxinterval * 3) / 4) {
 170                 syslog(LOG_ERR,
 171                        "<%s> mininterval must be between %e and %d",
 172                        __func__,
 173                        MIN_MININTERVAL,
 174                        (tmp->maxinterval * 3) / 4);
 175                 exit(1);
 176         }
 177         tmp->mininterval = (u_int)val;
 178
 179         MAYHAVE(val, "chlim", DEF_ADVCURHOPLIMIT);
 180         tmp->hoplimit = val & 0xff;
 181
 182         MAYHAVE(val, "raflags", 0);
 183         tmp->managedflg = val & ND_RA_FLAG_MANAGED;
 184         tmp->otherflg = val & ND_RA_FLAG_OTHER;
 185 #ifdef MIP6
 186         if (mobileip6)
 187                 tmp->haflg = val & ND_RA_FLAG_HA;
 188 #endif
 189 #ifndef ND_RA_FLAG_RTPREF_MASK
 190 #define ND_RA_FLAG_RTPREF_MASK  0x18 /* 00011000 */
 191 #define ND_RA_FLAG_RTPREF_RSV   0x10 /* 00010000 */
 192 #endif
 193         tmp->rtpref = val & ND_RA_FLAG_RTPREF_MASK;
 194         if (tmp->rtpref == ND_RA_FLAG_RTPREF_RSV) {
 195                 syslog(LOG_ERR, "<%s> invalid router preference on %s",
 196                        __func__, intface);
 197                 exit(1);
 198         }
 199
 200         MAYHAVE(val, "rltime", tmp->maxinterval * 3);
 201         if (val && (val < tmp->maxinterval || val > MAXROUTERLIFETIME)) {
 202                 syslog(LOG_ERR,
 203                        "<%s> router lifetime on %s must be 0 or"
 204                        " between %d and %d",
 205                        __func__, intface,
 206                        tmp->maxinterval, MAXROUTERLIFETIME);
 207                 exit(1);
 208         }
 209         /*
 210          * Basically, hosts MUST NOT send Router Advertisement messages at any
 211          * time (RFC 2461, Section 6.2.3). However, it would sometimes be
 212          * useful to allow hosts to advertise some parameters such as prefix
 213          * information and link MTU. Thus, we allow hosts to invoke rtadvd
 214          * only when router lifetime (on every advertising interface) is
 215          * explicitly set zero. (see also the above section)
 216          */
 217         if (val && forwarding == 0) {
 218                 syslog(LOG_WARNING,
 219                        "<%s> non zero router lifetime is specified for %s, "
 220                        "which must not be allowed for hosts.",
 221                        __func__, intface);
 222                 exit(1);
 223         }
 224         tmp->lifetime = val & 0xffff;
 225
 226         MAYHAVE(val, "rtime", DEF_ADVREACHABLETIME);
 227         if (val > MAXREACHABLETIME) {
 228                 syslog(LOG_ERR,
 229                        "<%s> reachable time must be no greater than %d",
 230                        __func__, MAXREACHABLETIME);
 231                 exit(1);
 232         }
 233         tmp->reachabletime = (u_int32_t)val;
 234
 235         MAYHAVE(val64, "retrans", DEF_ADVRETRANSTIMER);
 236         if (val64 < 0 || val64 > 0xffffffff) {
 237                 syslog(LOG_ERR,
 238                        "<%s> retrans time out of range", __func__);
 239                 exit(1);
 240         }
 241         tmp->retranstimer = (u_int32_t)val64;
 242
 243 #ifndef MIP6
 244         if (agetstr("hapref", &bp) || agetstr("hatime", &bp)) {
 245                 syslog(LOG_ERR,
 246                        "<%s> mobile-ip6 configuration not supported",
 247                        __func__);
 248                 exit(1);
 249         }
 250 #else
 251         if (!mobileip6) {
 252                 if (agetstr("hapref", &bp) || agetstr("hatime", &bp)) {
 253                         syslog(LOG_ERR,
 254                                "<%s> mobile-ip6 configuration without "
 255                                "proper command line option",
 256                                __func__);
 257                         exit(1);
 258                 }
 259         } else {
 260                 tmp->hapref = 0;
 261                 if ((val = agetnum("hapref")) >= 0)
 262                         tmp->hapref = (int16_t)val;
 263                 if (tmp->hapref != 0) {
 264                         tmp->hatime = 0;
 265                         MUSTHAVE(val, "hatime");
 266                         tmp->hatime = (u_int16_t)val;
 267                         if (tmp->hatime <= 0) {
 268                                 syslog(LOG_ERR,
 269                                        "<%s> home agent lifetime must be greater than 0",
 270                                        __func__);
 271                                 exit(1);
 272                         }
 273                 }
 274         }
 275 #endif
 276
 277         /* prefix information */
 278
 279         /*
 280          * This is an implementation specific parameter to consinder
 281          * link propagation delays and poorly synchronized clocks when
 282          * checking consistency of advertised lifetimes.
 283          */
 284         MAYHAVE(val, "clockskew", 0);
 285         tmp->clockskew = val;
 286
 287         if ((pfxs = agetnum("addrs")) < 0) {
 288                 /* auto configure prefix information */
 289                 if (agetstr("addr", &bp) || agetstr("addr1", &bp)) {
 290                         syslog(LOG_ERR,
 291                                "<%s> conflicting prefix configuration for %s: "
 292                                "automatic and manual config at the same time",
 293                                __func__, intface);
 294                         exit(1);
 295                 }
 296                 get_prefix(tmp);
 297         }
 298         else {
 299                 tmp->pfxs = pfxs;
 300                 for (i = 0; i < pfxs; i++) {
 301                         struct prefix *pfx;
 302                         char entbuf[256];
 303                         int added = (pfxs > 1) ? 1 : 0;
 304
 305                         /* allocate memory to store prefix information */
 306                         if ((pfx = malloc(sizeof(struct prefix))) == NULL) {
 307                                 syslog(LOG_ERR,
 308                                        "<%s> can't allocate enough memory",
 309                                        __func__);
 310                                 exit(1);
 311                         }
 312                         memset(pfx, 0, sizeof(*pfx));
 313
 314                         /* link into chain */
 315                         insque(pfx, &tmp->prefix);
 316                         pfx->rainfo = tmp;
 317
 318                         pfx->origin = PREFIX_FROM_CONFIG;
 319
 320                         makeentry(entbuf, sizeof(entbuf), i, "prefixlen",
 321                             added);
 322                         MAYHAVE(val, entbuf, 64);
 323                         if (val < 0 || val > 128) {
 324                                 syslog(LOG_ERR,
 325                                        "<%s> prefixlen out of range",
 326                                        __func__);
 327                                 exit(1);
 328                         }
 329                         pfx->prefixlen = (int)val;
 330
 331                         makeentry(entbuf, sizeof(entbuf), i, "pinfoflags",
 332                             added);
 333 #ifdef MIP6
 334                         if (mobileip6)
 335                         {
 336                                 MAYHAVE(val, entbuf,
 337                                     (ND_OPT_PI_FLAG_ONLINK|ND_OPT_PI_FLAG_AUTO|
 338                                          ND_OPT_PI_FLAG_ROUTER));
 339                         } else
 340 #endif
 341                         {
 342                                 MAYHAVE(val, entbuf,
 343                                     (ND_OPT_PI_FLAG_ONLINK|ND_OPT_PI_FLAG_AUTO));
 344                         }
 345                         pfx->onlinkflg = val & ND_OPT_PI_FLAG_ONLINK;
 346                         pfx->autoconfflg = val & ND_OPT_PI_FLAG_AUTO;
 347 #ifdef MIP6
 348                         pfx->routeraddr = val & ND_OPT_PI_FLAG_ROUTER;
 349 #endif
 350
 351                         makeentry(entbuf, sizeof(entbuf), i, "vltime", added);
 352                         MAYHAVE(val64, entbuf, DEF_ADVVALIDLIFETIME);
 353                         if (val64 < 0 || val64 > 0xffffffff) {
 354                                 syslog(LOG_ERR,
 355                                        "<%s> vltime out of range",
 356                                        __func__);
 357                                 exit(1);
 358                         }
 359                         pfx->validlifetime = (u_int32_t)val64;
 360
 361                         makeentry(entbuf, sizeof(entbuf), i, "vltimedecr",
 362                             added);
 363                         if (agetflag(entbuf)) {
 364                                 struct timeval now;
 365                                 gettimeofday(&now, 0);
 366                                 pfx->vltimeexpire =
 367                                         now.tv_sec + pfx->validlifetime;
 368                         }
 369
 370                         makeentry(entbuf, sizeof(entbuf), i, "pltime", added);
 371                         MAYHAVE(val64, entbuf, DEF_ADVPREFERREDLIFETIME);
 372                         if (val64 < 0 || val64 > 0xffffffff) {
 373                                 syslog(LOG_ERR,
 374                                        "<%s> pltime out of range",
 375                                        __func__);
 376                                 exit(1);
 377                         }
 378                         pfx->preflifetime = (u_int32_t)val64;
 379
 380                         makeentry(entbuf, sizeof(entbuf), i, "pltimedecr",
 381                             added);
 382                         if (agetflag(entbuf)) {
 383                                 struct timeval now;
 384                                 gettimeofday(&now, 0);
 385                                 pfx->pltimeexpire =
 386                                         now.tv_sec + pfx->preflifetime;
 387                         }
 388
 389                         makeentry(entbuf, sizeof(entbuf), i, "addr", added);
 390                         addr = (char *)agetstr(entbuf, &bp);
 391                         if (addr == NULL) {
 392                                 syslog(LOG_ERR,
 393                                        "<%s> need %s as an prefix for "
 394                                        "interface %s",
 395                                        __func__, entbuf, intface);
 396                                 exit(1);
 397                         }
 398                         if (inet_pton(AF_INET6, addr,
 399                                       &pfx->prefix) != 1) {
 400                                 syslog(LOG_ERR,
 401                                        "<%s> inet_pton failed for %s",
 402                                        __func__, addr);
 403                                 exit(1);
 404                         }
 405                         if (IN6_IS_ADDR_MULTICAST(&pfx->prefix)) {
 406                                 syslog(LOG_ERR,
 407                                        "<%s> multicast prefix(%s) must "
 408                                        "not be advertised (IF=%s)",
 409                                        __func__, addr, intface);
 410                                 exit(1);
 411                         }
 412                         if (IN6_IS_ADDR_LINKLOCAL(&pfx->prefix))
 413                                 syslog(LOG_NOTICE,
 414                                        "<%s> link-local prefix(%s) will be"
 415                                        " advertised on %s",
 416                                        __func__, addr, intface);
 417                 }
 418         }
 419
 420         MAYHAVE(val, "mtu", 0);
 421         if (val < 0 || val > 0xffffffff) {
 422                 syslog(LOG_ERR,
 423                        "<%s> mtu out of range", __func__);
 424                 exit(1);
 425         }
 426         tmp->linkmtu = (u_int32_t)val;
 427         if (tmp->linkmtu == 0) {
 428                 char *mtustr;
 429
 430                 if ((mtustr = (char *)agetstr("mtu", &bp)) &&
 431                     strcmp(mtustr, "auto") == 0)
 432                         tmp->linkmtu = tmp->phymtu;
 433         }
 434         else if (tmp->linkmtu < IPV6_MMTU || tmp->linkmtu > tmp->phymtu) {
 435                 syslog(LOG_ERR,
 436                        "<%s> advertised link mtu must be between"
 437                        " least MTU and physical link MTU",
 438                        __func__);
 439                 exit(1);
 440         }
 441
 442         /* route information */
 443
 444         MAYHAVE(val, "routes", 0);
 445         if (val < 0 || val > 0xffffffff) {
 446                 syslog(LOG_ERR,
 447                        "<%s> number of route information improper", __func__);
 448                 exit(1);
 449         }
 450         tmp->routes = val;
 451         for (i = 0; i < tmp->routes; i++) {
 452                 struct rtinfo *rti;
 453                 char entbuf[256];
 454                 int added = (tmp->routes > 1) ? 1 : 0;
 455
 456                 /* allocate memory to store prefix information */
 457                 if ((rti = malloc(sizeof(struct rtinfo))) == NULL) {
 458                         syslog(LOG_ERR,
 459                                "<%s> can't allocate enough memory",
 460                                __func__);
 461                         exit(1);
 462                 }
 463                 memset(rti, 0, sizeof(*rti));
 464
 465                 /* link into chain */
 466                 insque(rti, &tmp->route);
 467
 468                 makeentry(entbuf, sizeof(entbuf), i, "rtrplen", added);
 469                 MAYHAVE(val, entbuf, 64);
 470                 if (val < 0 || val > 128) {
 471                         syslog(LOG_ERR,
 472                                "<%s> prefixlen out of range",
 473                                __func__);
 474                         exit(1);
 475                 }
 476                 rti->prefixlen = (int)val;
 477
 478                 makeentry(entbuf, sizeof(entbuf), i, "rtrflags", added);
 479                 MAYHAVE(val, entbuf, 0);
 480                 rti->rtpref = val & ND_RA_FLAG_RTPREF_MASK;
 481                 if (rti->rtpref == ND_RA_FLAG_RTPREF_RSV) {
 482                         syslog(LOG_ERR, "<%s> invalid route preference",
 483                                __func__);
 484                         exit(1);
 485                 }
 486
 487                 makeentry(entbuf, sizeof(entbuf), i, "rtrltime", added);
 488                 /*
 489                  * XXX: since default value of route lifetime is not defined in
 490                  * draft-draves-route-selection-01.txt, I took the default
 491                  * value of valid lifetime of prefix as its default.
 492                  * It need be much considered.
 493                  */
 494                 MAYHAVE(val64, entbuf, DEF_ADVVALIDLIFETIME);
 495                 if (val64 < 0 || val64 > 0xffffffff) {
 496                         syslog(LOG_ERR,
 497                                "<%s> rtrltime out of range",
 498                                __func__);
 499                         exit(1);
 500                 }
 501                 rti->ltime = (u_int32_t)val64;
 502
 503                 makeentry(entbuf, sizeof(entbuf), i, "rtrprefix", added);
 504                 addr = (char *)agetstr(entbuf, &bp);
 505                 if (addr == NULL) {
 506                         syslog(LOG_ERR,
 507                                "<%s> need %s as an route for "
 508                                "interface %s",
 509                                __func__, entbuf, intface);
 510                         exit(1);
 511                 }
 512                 if (inet_pton(AF_INET6, addr, &rti->prefix) != 1) {
 513                         syslog(LOG_ERR,
 514                                "<%s> inet_pton failed for %s",
 515                                __func__, addr);
 516                         exit(1);
 517                 }
 518 #if 0
 519                 /*
 520                  * XXX: currently there's no restriction in route information
 521                  * prefix according to draft-draves-route-selection-01.txt,
 522                  * however I think the similar restriction be necessary.
 523                  */
 524                 MAYHAVE(val64, entbuf, DEF_ADVVALIDLIFETIME);
 525                 if (IN6_IS_ADDR_MULTICAST(&rti->prefix)) {
 526                         syslog(LOG_ERR,
 527                                "<%s> multicast route (%s) must "
 528                                "not be advertised (IF=%s)",
 529                                __func__, addr, intface);
 530                         exit(1);
 531                 }
 532                 if (IN6_IS_ADDR_LINKLOCAL(&rti->prefix)) {
 533                         syslog(LOG_NOTICE,
 534                                "<%s> link-local route (%s) must "
 535                                "not be advertised on %s",
 536                                __func__, addr, intface);
 537                         exit(1);
 538                 }
 539 #endif
 540         }
 541
 542         /* okey */
 543         tmp->next = ralist;
 544         ralist = tmp;
 545
 546         /* construct the sending packet */
 547         make_packet(tmp);
 548
 549         /* set timer */
 550         tmp->timer = rtadvd_add_timer(ra_timeout, ra_timer_update,
 551                                       tmp, tmp);
 552         ra_timer_update((void *)tmp, &tmp->timer->tm);
 553         rtadvd_set_timer(&tmp->timer->tm, tmp->timer);
 554 }
 555
 556 static void
 557 get_prefix(struct rainfo *rai)
 558 {
 559         struct ifaddrs *ifap, *ifa;
 560         struct prefix *pp;
 561         struct in6_addr *a;
 562         u_char *p, *ep, *m, *lim;
 563         u_char ntopbuf[INET6_ADDRSTRLEN];
 564
 565         if (getifaddrs(&ifap) < 0) {
 566                 syslog(LOG_ERR,
 567                        "<%s> can't get interface addresses",
 568                        __func__);
 569                 exit(1);
 570         }
 571         for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
 572                 int plen;
 573
 574                 if (strcmp(ifa->ifa_name, rai->ifname) != 0)
 575                         continue;
 576                 if (ifa->ifa_addr->sa_family != AF_INET6)
 577                         continue;
 578                 a = &((struct sockaddr_in6 *)ifa->ifa_addr)->sin6_addr;
 579                 if (IN6_IS_ADDR_LINKLOCAL(a))
 580                         continue;
 581
 582                 /* get prefix length */
 583                 m = (u_char *)&((struct sockaddr_in6 *)ifa->ifa_netmask)->sin6_addr;
 584                 lim = (u_char *)(ifa->ifa_netmask) + ifa->ifa_netmask->sa_len;
 585                 plen = prefixlen(m, lim);
 586                 if (plen < 0 || plen > 128) {
 587                         syslog(LOG_ERR, "<%s> failed to get prefixlen "
 588                                "or prefix is invalid",
 589                                __func__);
 590                         exit(1);
 591                 }
 592                 if (find_prefix(rai, a, plen)) {
 593                         /* ignore a duplicated prefix. */
 594                         continue;
 595                 }
 596
 597                 /* allocate memory to store prefix info. */
 598                 if ((pp = malloc(sizeof(*pp))) == NULL) {
 599                         syslog(LOG_ERR,
 600                                "<%s> can't get allocate buffer for prefix",
 601                                __func__);
 602                         exit(1);
 603                 }
 604                 memset(pp, 0, sizeof(*pp));
 605
 606                 /* set prefix, sweep bits outside of prefixlen */
 607                 pp->prefixlen = plen;
 608                 memcpy(&pp->prefix, a, sizeof(*a));
 609                 p = (u_char *)&pp->prefix;
 610                 ep = (u_char *)(&pp->prefix + 1);
 611                 while (m < lim)
 612                         *p++ &= *m++;
 613                 while (p < ep)
 614                         *p++ = 0x00;
 615
 616                 if (!inet_ntop(AF_INET6, &pp->prefix, ntopbuf,
 617                     sizeof(ntopbuf))) {
 618                         syslog(LOG_ERR, "<%s> inet_ntop failed", __func__);
 619                         exit(1);
 620                 }
 621                 syslog(LOG_DEBUG,
 622                        "<%s> add %s/%d to prefix list on %s",
 623                        __func__, ntopbuf, pp->prefixlen, rai->ifname);
 624
 625                 /* set other fields with protocol defaults */
 626                 pp->validlifetime = DEF_ADVVALIDLIFETIME;
 627                 pp->preflifetime = DEF_ADVPREFERREDLIFETIME;
 628                 pp->onlinkflg = 1;
 629                 pp->autoconfflg = 1;
 630                 pp->origin = PREFIX_FROM_KERNEL;
 631
 632                 /* link into chain */
 633                 insque(pp, &rai->prefix);
 634
 635                 /* counter increment */
 636                 rai->pfxs++;
 637         }
 638
 639         freeifaddrs(ifap);
 640 }
 641
 642 static void
 643 makeentry(char *buf, size_t len, int id, char *string, int add)
 644 {
 645         char *ep = buf + len;
 646
 647         strcpy(buf, string);
 648         if (add) {
 649                 char *cp;
 650
 651                 cp = (char *)index(buf, '\0');
 652                 snprintf(cp, ep - cp, "%d", id);
 653         }
 654 }
 655
 656 /*
 657  * Add a prefix to the list of specified interface and reconstruct
 658  * the outgoing packet.
 659  * The prefix must not be in the list.
 660  * XXX: other parameter of the prefix(e.g. lifetime) shoule be
 661  * able to be specified.
 662  */
 663 static void
 664 add_prefix(struct rainfo *rai, struct in6_prefixreq *ipr)
 665 {
 666         struct prefix *prefix;
 667         u_char ntopbuf[INET6_ADDRSTRLEN];
 668
 669         if ((prefix = malloc(sizeof(*prefix))) == NULL) {
 670                 syslog(LOG_ERR, "<%s> memory allocation failed",
 671                        __func__);
 672                 return;         /* XXX: error or exit? */
 673         }
 674         memset(prefix, 0, sizeof(*prefix));
 675         prefix->prefix = ipr->ipr_prefix.sin6_addr;
 676         prefix->prefixlen = ipr->ipr_plen;
 677         prefix->validlifetime = ipr->ipr_vltime;
 678         prefix->preflifetime = ipr->ipr_pltime;
 679         prefix->onlinkflg = ipr->ipr_raf_onlink;
 680         prefix->autoconfflg = ipr->ipr_raf_auto;
 681         prefix->origin = PREFIX_FROM_DYNAMIC;
 682
 683         insque(prefix, &rai->prefix);
 684         prefix->rainfo = rai;
 685
 686         syslog(LOG_DEBUG, "<%s> new prefix %s/%d was added on %s",
 687                __func__, inet_ntop(AF_INET6, &ipr->ipr_prefix.sin6_addr,
 688                                        ntopbuf, INET6_ADDRSTRLEN),
 689                ipr->ipr_plen, rai->ifname);
 690
 691         /* free the previous packet */
 692         free(rai->ra_data);
 693         rai->ra_data = NULL;
 694
 695         /* reconstruct the packet */
 696         rai->pfxs++;
 697         make_packet(rai);
 698
 699         /*
 700          * reset the timer so that the new prefix will be advertised quickly.
 701          */
 702         rai->initcounter = 0;
 703         ra_timer_update((void *)rai, &rai->timer->tm);
 704         rtadvd_set_timer(&rai->timer->tm, rai->timer);
 705 }
 706
 707 /*
 708  * Delete a prefix to the list of specified interface and reconstruct
 709  * the outgoing packet.
 710  * The prefix must be in the list.
 711  */
 712 void
 713 delete_prefix(struct prefix *prefix)
 714 {
 715         u_char ntopbuf[INET6_ADDRSTRLEN];
 716         struct rainfo *rai = prefix->rainfo;
 717
 718         remque(prefix);
 719         syslog(LOG_DEBUG, "<%s> prefix %s/%d was deleted on %s",
 720                __func__, inet_ntop(AF_INET6, &prefix->prefix,
 721                                        ntopbuf, INET6_ADDRSTRLEN),
 722                prefix->prefixlen, rai->ifname);
 723         if (prefix->timer)
 724                 rtadvd_remove_timer(&prefix->timer);
 725         free(prefix);
 726         rai->pfxs--;
 727 }
 728
 729 void
 730 invalidate_prefix(struct prefix *prefix)
 731 {
 732         u_char ntopbuf[INET6_ADDRSTRLEN];
 733         struct timeval timo;
 734         struct rainfo *rai = prefix->rainfo;
 735
 736         if (prefix->timer) {    /* sanity check */
 737                 syslog(LOG_ERR,
 738                     "<%s> assumption failure: timer already exists",
 739                     __func__);
 740                 exit(1);
 741         }
 742
 743         syslog(LOG_DEBUG, "<%s> prefix %s/%d was invalidated on %s, "
 744             "will expire in %ld seconds", __func__,
 745             inet_ntop(AF_INET6, &prefix->prefix, ntopbuf, INET6_ADDRSTRLEN),
 746             prefix->prefixlen, rai->ifname, (long)prefix_timo);
 747
 748         /* set the expiration timer */
 749         prefix->timer = rtadvd_add_timer(prefix_timeout, NULL, prefix, NULL);
 750         if (prefix->timer == NULL) {
 751                 syslog(LOG_ERR, "<%s> failed to add a timer for a prefix. "
 752                     "remove the prefix", __func__);
 753                 delete_prefix(prefix);
 754         }
 755         timo.tv_sec = prefix_timo;
 756         timo.tv_usec = 0;
 757         rtadvd_set_timer(&timo, prefix->timer);
 758 }
 759
 760 static struct rtadvd_timer *
 761 prefix_timeout(void *arg)
 762 {
 763         struct prefix *prefix = (struct prefix *)arg;
 764
 765         delete_prefix(prefix);
 766
 767         return(NULL);
 768 }
 769
 770 void
 771 update_prefix(struct prefix * prefix)
 772 {
 773         u_char ntopbuf[INET6_ADDRSTRLEN];
 774         struct rainfo *rai = prefix->rainfo;
 775
 776         if (prefix->timer == NULL) { /* sanity check */
 777                 syslog(LOG_ERR,
 778                     "<%s> assumption failure: timer does not exist",
 779                     __func__);
 780                 exit(1);
 781         }
 782
 783         syslog(LOG_DEBUG, "<%s> prefix %s/%d was re-enabled on %s",
 784             __func__, inet_ntop(AF_INET6, &prefix->prefix, ntopbuf,
 785             INET6_ADDRSTRLEN), prefix->prefixlen, rai->ifname);
 786
 787         /* stop the expiration timer */
 788         rtadvd_remove_timer(&prefix->timer);
 789 }
 790
 791 /*
 792  * Try to get an in6_prefixreq contents for a prefix which matches
 793  * ipr->ipr_prefix and ipr->ipr_plen and belongs to
 794  * the interface whose name is ipr->ipr_name[].
 795  */
 796 static int
 797 init_prefix(struct in6_prefixreq *ipr)
 798 {
 799 #if 0
 800         int s;
 801
 802         if ((s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0) {
 803                 syslog(LOG_ERR, "<%s> socket: %s", __func__,
 804                        strerror(errno));
 805                 exit(1);
 806         }
 807
 808         if (ioctl(s, SIOCGIFPREFIX_IN6, (caddr_t)ipr) < 0) {
 809                 syslog(LOG_INFO, "<%s> ioctl:SIOCGIFPREFIX %s", __func__,
 810                        strerror(errno));
 811
 812                 ipr->ipr_vltime = DEF_ADVVALIDLIFETIME;
 813                 ipr->ipr_pltime = DEF_ADVPREFERREDLIFETIME;
 814                 ipr->ipr_raf_onlink = 1;
 815                 ipr->ipr_raf_auto = 1;
 816                 /* omit other field initialization */
 817         }
 818         else if (ipr->ipr_origin < PR_ORIG_RR) {
 819                 u_char ntopbuf[INET6_ADDRSTRLEN];
 820
 821                 syslog(LOG_WARNING, "<%s> Added prefix(%s)'s origin %d is"
 822                        "lower than PR_ORIG_RR(router renumbering)."
 823                        "This should not happen if I am router", __func__,
 824                        inet_ntop(AF_INET6, &ipr->ipr_prefix.sin6_addr, ntopbuf,
 825                                  sizeof(ntopbuf)), ipr->ipr_origin);
 826                 close(s);
 827                 return 1;
 828         }
 829
 830         close(s);
 831         return 0;
 832 #else
 833         ipr->ipr_vltime = DEF_ADVVALIDLIFETIME;
 834         ipr->ipr_pltime = DEF_ADVPREFERREDLIFETIME;
 835         ipr->ipr_raf_onlink = 1;
 836         ipr->ipr_raf_auto = 1;
 837         return 0;
 838 #endif
 839 }
 840
 841 void
 842 make_prefix(struct rainfo *rai, int ifindex, struct in6_addr *addr, int plen)
 843 {
 844         struct in6_prefixreq ipr;
 845
 846         memset(&ipr, 0, sizeof(ipr));
 847         if (if_indextoname(ifindex, ipr.ipr_name) == NULL) {
 848                 syslog(LOG_ERR, "<%s> Prefix added interface No.%d doesn't"
 849                        "exist. This should not happen! %s", __func__,
 850                        ifindex, strerror(errno));
 851                 exit(1);
 852         }
 853         ipr.ipr_prefix.sin6_len = sizeof(ipr.ipr_prefix);
 854         ipr.ipr_prefix.sin6_family = AF_INET6;
 855         ipr.ipr_prefix.sin6_addr = *addr;
 856         ipr.ipr_plen = plen;
 857
 858         if (init_prefix(&ipr))
 859                 return; /* init failed by some error */
 860         add_prefix(rai, &ipr);
 861 }
 862
 863 void
 864 make_packet(struct rainfo *rainfo)
 865 {
 866         size_t packlen, lladdroptlen = 0;
 867         char *buf;
 868         struct nd_router_advert *ra;
 869         struct nd_opt_prefix_info *ndopt_pi;
 870         struct nd_opt_mtu *ndopt_mtu;
 871 #ifdef MIP6
 872         struct nd_opt_advinterval *ndopt_advint;
 873         struct nd_opt_homeagent_info *ndopt_hai;
 874 #endif
 875         struct nd_opt_route_info *ndopt_rti;
 876         struct prefix *pfx;
 877         struct rtinfo *rti;
 878
 879         /* calculate total length */
 880         packlen = sizeof(struct nd_router_advert);
 881         if (rainfo->advlinkopt) {
 882                 if ((lladdroptlen = lladdropt_length(rainfo->sdl)) == 0) {
 883                         syslog(LOG_INFO,
 884                                "<%s> link-layer address option has"
 885                                " null length on %s."
 886                                " Treat as not included.",
 887                                __func__, rainfo->ifname);
 888                         rainfo->advlinkopt = 0;
 889                 }
 890                 packlen += lladdroptlen;
 891         }
 892         if (rainfo->pfxs)
 893                 packlen += sizeof(struct nd_opt_prefix_info) * rainfo->pfxs;
 894         if (rainfo->linkmtu)
 895                 packlen += sizeof(struct nd_opt_mtu);
 896 #ifdef MIP6
 897         if (mobileip6 && rainfo->maxinterval)
 898                 packlen += sizeof(struct nd_opt_advinterval);
 899         if (mobileip6 && rainfo->hatime)
 900                 packlen += sizeof(struct nd_opt_homeagent_info);
 901 #endif
 902 #ifdef ND_OPT_ROUTE_INFO
 903         for (rti = rainfo->route.next; rti != &rainfo->route; rti = rti->next)
 904                 packlen += sizeof(struct nd_opt_route_info) +
 905                            ((rti->prefixlen + 0x3f) >> 6) * 8;
 906 #endif
 907
 908         /* allocate memory for the packet */
 909         if ((buf = malloc(packlen)) == NULL) {
 910                 syslog(LOG_ERR,
 911                        "<%s> can't get enough memory for an RA packet",
 912                        __func__);
 913                 exit(1);
 914         }
 915         if (rainfo->ra_data) {
 916                 /* free the previous packet */
 917                 free(rainfo->ra_data);
 918                 rainfo->ra_data = NULL;
 919         }
 920         rainfo->ra_data = buf;
 921         /* XXX: what if packlen > 576? */
 922         rainfo->ra_datalen = packlen;
 923
 924         /*
 925          * construct the packet
 926          */
 927         ra = (struct nd_router_advert *)buf;
 928         ra->nd_ra_type = ND_ROUTER_ADVERT;
 929         ra->nd_ra_code = 0;
 930         ra->nd_ra_cksum = 0;
 931         ra->nd_ra_curhoplimit = (u_int8_t)(0xff & rainfo->hoplimit);
 932         ra->nd_ra_flags_reserved = 0; /* just in case */
 933         /*
 934          * XXX: the router preference field, which is a 2-bit field, should be
 935          * initialized before other fields.
 936          */
 937         ra->nd_ra_flags_reserved = 0xff & rainfo->rtpref;
 938         ra->nd_ra_flags_reserved |=
 939                 rainfo->managedflg ? ND_RA_FLAG_MANAGED : 0;
 940         ra->nd_ra_flags_reserved |=
 941                 rainfo->otherflg ? ND_RA_FLAG_OTHER : 0;
 942 #ifdef MIP6
 943         ra->nd_ra_flags_reserved |=
 944                 rainfo->haflg ? ND_RA_FLAG_HA : 0;
 945 #endif
 946         ra->nd_ra_router_lifetime = htons(rainfo->lifetime);
 947         ra->nd_ra_reachable = htonl(rainfo->reachabletime);
 948         ra->nd_ra_retransmit = htonl(rainfo->retranstimer);
 949         buf += sizeof(*ra);
 950
 951         if (rainfo->advlinkopt) {
 952                 lladdropt_fill(rainfo->sdl, (struct nd_opt_hdr *)buf);
 953                 buf += lladdroptlen;
 954         }
 955
 956         if (rainfo->linkmtu) {
 957                 ndopt_mtu = (struct nd_opt_mtu *)buf;
 958                 ndopt_mtu->nd_opt_mtu_type = ND_OPT_MTU;
 959                 ndopt_mtu->nd_opt_mtu_len = 1;
 960                 ndopt_mtu->nd_opt_mtu_reserved = 0;
 961                 ndopt_mtu->nd_opt_mtu_mtu = htonl(rainfo->linkmtu);
 962                 buf += sizeof(struct nd_opt_mtu);
 963         }
 964
 965 #ifdef MIP6
 966         if (mobileip6 && rainfo->maxinterval) {
 967                 ndopt_advint = (struct nd_opt_advinterval *)buf;
 968                 ndopt_advint->nd_opt_adv_type = ND_OPT_ADVINTERVAL;
 969                 ndopt_advint->nd_opt_adv_len = 1;
 970                 ndopt_advint->nd_opt_adv_reserved = 0;
 971                 ndopt_advint->nd_opt_adv_interval = htonl(rainfo->maxinterval *
 972                                                           1000);
 973                 buf += sizeof(struct nd_opt_advinterval);
 974         }
 975 #endif
 976
 977 #ifdef MIP6
 978         if (rainfo->hatime) {
 979                 ndopt_hai = (struct nd_opt_homeagent_info *)buf;
 980                 ndopt_hai->nd_opt_hai_type = ND_OPT_HOMEAGENT_INFO;
 981                 ndopt_hai->nd_opt_hai_len = 1;
 982                 ndopt_hai->nd_opt_hai_reserved = 0;
 983                 ndopt_hai->nd_opt_hai_preference = htons(rainfo->hapref);
 984                 ndopt_hai->nd_opt_hai_lifetime = htons(rainfo->hatime);
 985                 buf += sizeof(struct nd_opt_homeagent_info);
 986         }
 987 #endif
 988
 989         for (pfx = rainfo->prefix.next;
 990              pfx != &rainfo->prefix; pfx = pfx->next) {
 991                 u_int32_t vltime, pltime;
 992                 struct timeval now;
 993
 994                 ndopt_pi = (struct nd_opt_prefix_info *)buf;
 995                 ndopt_pi->nd_opt_pi_type = ND_OPT_PREFIX_INFORMATION;
 996                 ndopt_pi->nd_opt_pi_len = 4;
 997                 ndopt_pi->nd_opt_pi_prefix_len = pfx->prefixlen;
 998                 ndopt_pi->nd_opt_pi_flags_reserved = 0;
 999                 if (pfx->onlinkflg)
1000                         ndopt_pi->nd_opt_pi_flags_reserved |=
1001                                 ND_OPT_PI_FLAG_ONLINK;
1002                 if (pfx->autoconfflg)
1003                         ndopt_pi->nd_opt_pi_flags_reserved |=
1004                                 ND_OPT_PI_FLAG_AUTO;
1005 #ifdef MIP6
1006                 if (pfx->routeraddr)
1007                         ndopt_pi->nd_opt_pi_flags_reserved |=
1008                                 ND_OPT_PI_FLAG_ROUTER;
1009 #endif
1010                 if (pfx->timer)
1011                         vltime = 0;
1012                 else {
1013                         if (pfx->vltimeexpire || pfx->pltimeexpire)
1014                                 gettimeofday(&now, NULL);
1015                         if (pfx->vltimeexpire == 0)
1016                                 vltime = pfx->validlifetime;
1017                         else
1018                                 vltime = (pfx->vltimeexpire > now.tv_sec) ?
1019                                     pfx->vltimeexpire - now.tv_sec : 0;
1020                 }
1021                 if (pfx->timer)
1022                         pltime = 0;
1023                 else {
1024                         if (pfx->pltimeexpire == 0)
1025                                 pltime = pfx->preflifetime;
1026                         else
1027                                 pltime = (pfx->pltimeexpire > now.tv_sec) ?
1028                                     pfx->pltimeexpire - now.tv_sec : 0;
1029                 }
1030                 if (vltime < pltime) {
1031                         /*
1032                          * this can happen if vltime is decrement but pltime
1033                          * is not.
1034                          */
1035                         pltime = vltime;
1036                 }
1037                 ndopt_pi->nd_opt_pi_valid_time = htonl(vltime);
1038                 ndopt_pi->nd_opt_pi_preferred_time = htonl(pltime);
1039                 ndopt_pi->nd_opt_pi_reserved2 = 0;
1040                 ndopt_pi->nd_opt_pi_prefix = pfx->prefix;
1041
1042                 buf += sizeof(struct nd_opt_prefix_info);
1043         }
1044
1045 #ifdef ND_OPT_ROUTE_INFO
1046         for (rti = rainfo->route.next; rti != &rainfo->route; rti = rti->next) {
1047                 u_int8_t psize = (rti->prefixlen + 0x3f) >> 6;
1048
1049                 ndopt_rti = (struct nd_opt_route_info *)buf;
1050                 ndopt_rti->nd_opt_rti_type = ND_OPT_ROUTE_INFO;
1051                 ndopt_rti->nd_opt_rti_len = 1 + psize;
1052                 ndopt_rti->nd_opt_rti_prefixlen = rti->prefixlen;
1053                 ndopt_rti->nd_opt_rti_flags = 0xff & rti->rtpref;
1054                 ndopt_rti->nd_opt_rti_lifetime = htonl(rti->ltime);
1055                 memcpy(ndopt_rti + 1, &rti->prefix, psize * 8);
1056                 buf += sizeof(struct nd_opt_route_info) + psize * 8;
1057         }
1058 #endif
1059
1060         return;
1061 }
1062
1063 static int
1064 getinet6sysctl(int code)
1065 {
1066         int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, 0 };
1067         int value;
1068         size_t size;
1069
1070         mib[3] = code;
1071         size = sizeof(value);
1072         if (sysctl(mib, sizeof(mib)/sizeof(mib[0]), &value, &size, NULL, 0)
1073             < 0) {
1074                 syslog(LOG_ERR, "<%s>: failed to get ip6 sysctl(%d): %s",
1075                        __func__, code,
1076                        strerror(errno));
1077                 return(-1);
1078         }
1079         else
1080                 return(value);
1081 }