usr.sbin/IPXrouted/tables.c

   1 /*
   2  * Copyright (c) 1985, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Copyright (c) 1995 John Hay.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. All advertising materials mentioning features or use of this software
  16  *    must display the following acknowledgement:
  17  *      This product includes software developed by the University of
  18  *      California, Berkeley and its contributors.
  19  * 4. Neither the name of the University nor the names of its contributors
  20  *    may be used to endorse or promote products derived from this software
  21  *    without specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  *
  35  * $FreeBSD: src/usr.sbin/IPXrouted/tables.c,v 1.7 1999/08/28 01:15:05 peter Exp $
  36  * $DragonFly: src/usr.sbin/IPXrouted/tables.c,v 1.3 2004/03/11 09:38:59 hmp Exp $
  37  *
  38  * @(#)tables.c 8.1 (Berkeley) 6/5/93
  39  */
  40
  41 /*
  42  * Routing Table Management Daemon
  43  */
  44 #include "defs.h"
  45 #include <sys/ioctl.h>
  46 #include <errno.h>
  47 #include <search.h>
  48 #include <stdlib.h>
  49 #include <unistd.h>
  50
  51 #ifndef DEBUG
  52 #define DEBUG   0
  53 #endif
  54
  55 #define FIXLEN(s) { if ((s)->sa_len == 0) (s)->sa_len = sizeof (*(s));}
  56
  57 int     install = !DEBUG;               /* if 1 call kernel */
  58 int     delete = 1;
  59
  60 struct  rthash nethash[ROUTEHASHSIZ];
  61
  62 /*
  63  * Lookup dst in the tables for an exact match.
  64  */
  65 struct rt_entry *
  66 rtlookup(struct sockaddr *dst)
  67 {
  68         struct rt_entry *rt;
  69         struct rthash *rh;
  70         u_int hash;
  71         struct afhash h;
  72
  73         if (dst->sa_family >= AF_MAX)
  74                 return (0);
  75         (*afswitch[dst->sa_family].af_hash)(dst, &h);
  76         hash = h.afh_nethash;
  77         rh = &nethash[hash & ROUTEHASHMASK];
  78         for (rt = rh->rt_forw; rt != (struct rt_entry *)rh; rt = rt->rt_forw) {
  79                 if (rt->rt_hash != hash)
  80                         continue;
  81                 if (equal(&rt->rt_dst, dst))
  82                         return (rt);
  83         }
  84         return (0);
  85 }
  86
  87 /*
  88  * Find a route to dst as the kernel would.
  89  */
  90 struct rt_entry *
  91 rtfind(struct sockaddr *dst)
  92 {
  93         struct rt_entry *rt;
  94         struct rthash *rh;
  95         u_int hash;
  96         struct afhash h;
  97         int af = dst->sa_family;
  98         int (*match)() = 0;
  99
 100         if (af >= AF_MAX)
 101                 return (0);
 102         (*afswitch[af].af_hash)(dst, &h);
 103
 104         hash = h.afh_nethash;
 105         rh = &nethash[hash & ROUTEHASHMASK];
 106         match = afswitch[af].af_netmatch;
 107         for (rt = rh->rt_forw; rt != (struct rt_entry *)rh; rt = rt->rt_forw) {
 108                 if (rt->rt_hash != hash)
 109                         continue;
 110                 if (rt->rt_dst.sa_family == af &&
 111                     (*match)(&rt->rt_dst, dst))
 112                         return (rt);
 113         }
 114         return (0);
 115 }
 116
 117 void
 118 rtadd(struct sockaddr *dst, struct sockaddr *gate, short metric, short ticks,
 119       int state)
 120 {
 121         struct afhash h;
 122         struct rt_entry *rt;
 123         struct rthash *rh;
 124         int af = dst->sa_family, flags;
 125         u_int hash;
 126
 127         FIXLEN(dst);
 128         FIXLEN(gate);
 129         if (af >= AF_MAX)
 130                 return;
 131         (*afswitch[af].af_hash)(dst, &h);
 132         flags = (*afswitch[af].af_ishost)(dst) ? RTF_HOST : 0;
 133         hash = h.afh_nethash;
 134         rh = &nethash[hash & ROUTEHASHMASK];
 135         rt = (struct rt_entry *)malloc(sizeof (*rt));
 136         if (rt == 0)
 137                 return;
 138         rt->rt_hash = hash;
 139         rt->rt_dst = *dst;
 140         rt->rt_router = *gate;
 141         rt->rt_metric = metric;
 142         rt->rt_ticks = ticks;
 143         rt->rt_timer = 0;
 144         rt->rt_flags = RTF_UP | flags;
 145         rt->rt_state = state | RTS_CHANGED;
 146         rt->rt_ifp = if_ifwithnet(&rt->rt_router);
 147         rt->rt_clone = NULL;
 148         if (metric)
 149                 rt->rt_flags |= RTF_GATEWAY;
 150         insque(rt, rh);
 151         TRACE_ACTION("ADD", rt);
 152         /*
 153          * If the ioctl fails because the gateway is unreachable
 154          * from this host, discard the entry.  This should only
 155          * occur because of an incorrect entry in /etc/gateways.
 156          */
 157         if (install && rtioctl(ADD, &rt->rt_rt) < 0) {
 158                 if (errno != EEXIST)
 159                         perror("SIOCADDRT");
 160                 if (errno == ENETUNREACH) {
 161                         TRACE_ACTION("DELETE", rt);
 162                         remque(rt);
 163                         free((char *)rt);
 164                 }
 165         }
 166 }
 167
 168 void
 169 rtadd_clone(struct rt_entry *ort, struct sockaddr *dst, struct sockaddr *gate,
 170             short metric, short ticks, int state)
 171 {
 172         struct afhash h;
 173         struct rt_entry *rt;
 174         struct rthash *rh;
 175         int af = dst->sa_family, flags;
 176         u_int hash;
 177
 178         FIXLEN(dst);
 179         FIXLEN(gate);
 180         if (af >= AF_MAX)
 181                 return;
 182         (*afswitch[af].af_hash)(dst, &h);
 183         flags = (*afswitch[af].af_ishost)(dst) ? RTF_HOST : 0;
 184         hash = h.afh_nethash;
 185         rh = &nethash[hash & ROUTEHASHMASK];
 186         rt = (struct rt_entry *)malloc(sizeof (*rt));
 187         if (rt == 0)
 188                 return;
 189         rt->rt_hash = hash;
 190         rt->rt_dst = *dst;
 191         rt->rt_router = *gate;
 192         rt->rt_metric = metric;
 193         rt->rt_ticks = ticks;
 194         rt->rt_timer = 0;
 195         rt->rt_flags = RTF_UP | flags;
 196         rt->rt_state = state | RTS_CHANGED;
 197         rt->rt_ifp = if_ifwithnet(&rt->rt_router);
 198         rt->rt_clone = NULL;
 199         rt->rt_forw = NULL;
 200         rt->rt_back = NULL;
 201         if (metric)
 202                 rt->rt_flags |= RTF_GATEWAY;
 203
 204         while(ort->rt_clone != NULL)
 205                 ort = ort->rt_clone;
 206         ort->rt_clone = rt;
 207         TRACE_ACTION("ADD_CLONE", rt);
 208 }
 209
 210 void
 211 rtchange(struct rt_entry *rt, struct sockaddr *gate, short metric, short ticks)
 212 {
 213         int doioctl = 0, metricchanged = 0;
 214         struct rtuentry oldroute;
 215
 216         FIXLEN(gate);
 217         /*
 218          * Handling of clones.
 219          * When the route changed and it had clones, handle it special.
 220          * 1. If the new route is cheaper than the clone(s), free the clones.
 221          * 2. If the new route is the same cost, it may be one of the clones,
 222          *    search for it and free it.
 223          * 3. If the new route is more expensive than the clone(s), use the
 224          *    values of the clone(s).
 225          */
 226         if (rt->rt_clone) {
 227                 if ((ticks < rt->rt_clone->rt_ticks) ||
 228                     ((ticks == rt->rt_clone->rt_ticks) &&
 229                      (metric < rt->rt_clone->rt_metric))) {
 230                         /*
 231                          * Free all clones.
 232                          */
 233                         struct rt_entry *trt, *nrt;
 234
 235                         trt = rt->rt_clone;
 236                         rt->rt_clone = NULL;
 237                         while(trt) {
 238                                 nrt = trt->rt_clone;
 239                                 free((char *)trt);
 240                                 trt = nrt;
 241                         }
 242                 } else if ((ticks == rt->rt_clone->rt_ticks) &&
 243                      (metric == rt->rt_clone->rt_metric)) {
 244                         struct rt_entry *prt, *trt;
 245
 246                         prt = rt;
 247                         trt = rt->rt_clone;
 248
 249                         while(trt) {
 250                                 if (equal(&trt->rt_router, gate)) {
 251                                         prt->rt_clone = trt->rt_clone;
 252                                         free(trt);
 253                                         trt = prt->rt_clone;
 254                                 } else {
 255                                         prt = trt;
 256                                         trt = trt->rt_clone;
 257                                 }
 258                         }
 259                 } else {
 260                         /*
 261                          * Use the values of the first clone.
 262                          * Delete the corresponding clone.
 263                          */
 264                         struct rt_entry *trt;
 265
 266                         trt = rt->rt_clone;
 267                         rt->rt_clone = rt->rt_clone->rt_clone;
 268                         metric = trt->rt_metric;
 269                         ticks = trt->rt_ticks;
 270                         *gate = trt->rt_router;
 271                         free((char *)trt);
 272                 }
 273         }
 274
 275         if (!equal(&rt->rt_router, gate))
 276                 doioctl++;
 277         if ((metric != rt->rt_metric) || (ticks != rt->rt_ticks))
 278                 metricchanged++;
 279         if (doioctl || metricchanged) {
 280                 TRACE_ACTION("CHANGE FROM", rt);
 281                 if (doioctl) {
 282                         oldroute = rt->rt_rt;
 283                         rt->rt_router = *gate;
 284                 }
 285                 rt->rt_metric = metric;
 286                 rt->rt_ticks = ticks;
 287                 if ((rt->rt_state & RTS_INTERFACE) && metric) {
 288                         rt->rt_state &= ~RTS_INTERFACE;
 289                         if(rt->rt_ifp)
 290                                 syslog(LOG_ERR,
 291                                 "changing route from interface %s (timed out)",
 292                                 rt->rt_ifp->int_name);
 293                         else
 294                                 syslog(LOG_ERR,
 295                                 "changing route from interface ??? (timed out)");
 296                 }
 297                 if (metric)
 298                         rt->rt_flags |= RTF_GATEWAY;
 299                 else
 300                         rt->rt_flags &= ~RTF_GATEWAY;
 301                 rt->rt_ifp = if_ifwithnet(&rt->rt_router);
 302                 rt->rt_state |= RTS_CHANGED;
 303                 TRACE_ACTION("CHANGE TO", rt);
 304         }
 305         if (doioctl && install) {
 306 #ifndef RTM_ADD
 307                 if (rtioctl(ADD, &rt->rt_rt) < 0)
 308                   syslog(LOG_ERR, "rtioctl ADD dst %s, gw %s: %m",
 309                    ipx_ntoa(&((struct sockaddr_ipx *)&rt->rt_dst)->sipx_addr),
 310                    ipx_ntoa(&((struct sockaddr_ipx *)&rt->rt_router)->sipx_addr));
 311                 if (delete && rtioctl(DELETE, &oldroute) < 0)
 312                         perror("rtioctl DELETE");
 313 #else
 314                 if (delete == 0) {
 315                         if (rtioctl(ADD, &rt->rt_rt) >= 0)
 316                                 return;
 317                 } else {
 318                         if (rtioctl(CHANGE, &rt->rt_rt) >= 0)
 319                                 return;
 320                 }
 321                 syslog(LOG_ERR, "rtioctl ADD dst %s, gw %s: %m",
 322                    ipxdp_ntoa(&((struct sockaddr_ipx *)&rt->rt_dst)->sipx_addr),
 323                    ipxdp_ntoa(&((struct sockaddr_ipx *)&rt->rt_router)->sipx_addr));
 324 #endif
 325         }
 326 }
 327
 328 void
 329 rtdelete(struct rt_entry *rt)
 330 {
 331         struct sockaddr *sa = &(rt->rt_router);
 332
 333         FIXLEN(sa);
 334         sa = &(rt->rt_dst);
 335         FIXLEN(sa);
 336         if (rt->rt_clone) {
 337                 /*
 338                  * If there is a clone we just do a rt_change to it.
 339                  */
 340                 struct rt_entry *trt = rt->rt_clone;
 341                 rtchange(rt, &trt->rt_router, trt->rt_metric, trt->rt_ticks);
 342                 return;
 343         }
 344         if (rt->rt_state & RTS_INTERFACE) {
 345                 if (rt->rt_ifp)
 346                         syslog(LOG_ERR,
 347                                 "deleting route to interface %s (timed out)",
 348                                 rt->rt_ifp->int_name);
 349                 else
 350                         syslog(LOG_ERR,
 351                                 "deleting route to interface ??? (timed out)");
 352         }
 353         TRACE_ACTION("DELETE", rt);
 354         if (install && rtioctl(DELETE, &rt->rt_rt) < 0)
 355                 perror("rtioctl DELETE");
 356         remque(rt);
 357         free((char *)rt);
 358 }
 359
 360 void
 361 rtinit(void)
 362 {
 363         struct rthash *rh;
 364
 365         for (rh = nethash; rh < &nethash[ROUTEHASHSIZ]; rh++)
 366                 rh->rt_forw = rh->rt_back = (struct rt_entry *)rh;
 367 }
 368 int seqno;
 369
 370 int
 371 rtioctl(int action, struct rtuentry *ort)
 372 {
 373 #ifndef RTM_ADD
 374         if (install == 0)
 375                 return (errno = 0);
 376
 377         ort->rtu_rtflags = ort->rtu_flags;
 378
 379         switch (action) {
 380
 381         case ADD:
 382                 return (ioctl(s, SIOCADDRT, (char *)ort));
 383
 384         case DELETE:
 385                 return (ioctl(s, SIOCDELRT, (char *)ort));
 386
 387         default:
 388                 return (-1);
 389         }
 390 #else /* RTM_ADD */
 391         struct {
 392                 struct rt_msghdr w_rtm;
 393                 struct sockaddr w_dst;
 394                 struct sockaddr w_gate;
 395                 struct sockaddr_ipx w_netmask;
 396         } w;
 397 #define rtm w.w_rtm
 398
 399         bzero((char *)&w, sizeof(w));
 400         rtm.rtm_msglen = sizeof(w);
 401         rtm.rtm_version = RTM_VERSION;
 402         rtm.rtm_type = (action == ADD ? RTM_ADD :
 403                                 (action == DELETE ? RTM_DELETE : RTM_CHANGE));
 404         rtm.rtm_flags = ort->rtu_flags;
 405         rtm.rtm_seq = ++seqno;
 406         rtm.rtm_addrs = RTA_DST|RTA_GATEWAY;
 407         bcopy((char *)&ort->rtu_dst, (char *)&w.w_dst, sizeof(w.w_dst));
 408         bcopy((char *)&ort->rtu_router, (char *)&w.w_gate, sizeof(w.w_gate));
 409         w.w_gate.sa_family = w.w_dst.sa_family = AF_IPX;
 410         w.w_gate.sa_len = w.w_dst.sa_len = sizeof(w.w_dst);
 411         if (rtm.rtm_flags & RTF_HOST) {
 412                 rtm.rtm_msglen -= sizeof(w.w_netmask);
 413         } else {
 414                 rtm.rtm_addrs |= RTA_NETMASK;
 415                 w.w_netmask = ipx_netmask;
 416                 rtm.rtm_msglen -= sizeof(w.w_netmask) - ipx_netmask.sipx_len;
 417         }
 418         errno = 0;
 419         return write(r, (char *)&w, rtm.rtm_msglen);
 420 #endif  /* RTM_ADD */
 421 }