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 <stdlib.h>
  48 #include <unistd.h>
  49
  50 #ifndef DEBUG
  51 #define DEBUG   0
  52 #endif
  53
  54 #define FIXLEN(s) { if ((s)->sa_len == 0) (s)->sa_len = sizeof (*(s));}
  55
  56 int     install = !DEBUG;               /* if 1 call kernel */
  57 int     delete = 1;
  58
  59 struct  rthash nethash[ROUTEHASHSIZ];
  60
  61 /*
  62  * Lookup dst in the tables for an exact match.
  63  */
  64 struct rt_entry *
  65 rtlookup(struct sockaddr *dst)
  66 {
  67         struct rt_entry *rt;
  68         struct rthash *rh;
  69         u_int hash;
  70         struct afhash h;
  71
  72         if (dst->sa_family >= AF_MAX)
  73                 return (0);
  74         (*afswitch[dst->sa_family].af_hash)(dst, &h);
  75         hash = h.afh_nethash;
  76         rh = &nethash[hash & ROUTEHASHMASK];
  77         for (rt = rh->rt_forw; rt != (struct rt_entry *)rh; rt = rt->rt_forw) {
  78                 if (rt->rt_hash != hash)
  79                         continue;
  80                 if (equal(&rt->rt_dst, dst))
  81                         return (rt);
  82         }
  83         return (0);
  84 }
  85
  86 /*
  87  * Find a route to dst as the kernel would.
  88  */
  89 struct rt_entry *
  90 rtfind(struct sockaddr *dst)
  91 {
  92         struct rt_entry *rt;
  93         struct rthash *rh;
  94         u_int hash;
  95         struct afhash h;
  96         int af = dst->sa_family;
  97         int (*match)() = 0;
  98
  99         if (af >= AF_MAX)
 100                 return (0);
 101         (*afswitch[af].af_hash)(dst, &h);
 102
 103         hash = h.afh_nethash;
 104         rh = &nethash[hash & ROUTEHASHMASK];
 105         match = afswitch[af].af_netmatch;
 106         for (rt = rh->rt_forw; rt != (struct rt_entry *)rh; rt = rt->rt_forw) {
 107                 if (rt->rt_hash != hash)
 108                         continue;
 109                 if (rt->rt_dst.sa_family == af &&
 110                     (*match)(&rt->rt_dst, dst))
 111                         return (rt);
 112         }
 113         return (0);
 114 }
 115
 116 void
 117 rtadd(struct sockaddr *dst, struct sockaddr *gate, short metric, short ticks,
 118       int state)
 119 {
 120         struct afhash h;
 121         struct rt_entry *rt;
 122         struct rthash *rh;
 123         int af = dst->sa_family, flags;
 124         u_int hash;
 125
 126         FIXLEN(dst);
 127         FIXLEN(gate);
 128         if (af >= AF_MAX)
 129                 return;
 130         (*afswitch[af].af_hash)(dst, &h);
 131         flags = (*afswitch[af].af_ishost)(dst) ? RTF_HOST : 0;
 132         hash = h.afh_nethash;
 133         rh = &nethash[hash & ROUTEHASHMASK];
 134         rt = (struct rt_entry *)malloc(sizeof (*rt));
 135         if (rt == 0)
 136                 return;
 137         rt->rt_hash = hash;
 138         rt->rt_dst = *dst;
 139         rt->rt_router = *gate;
 140         rt->rt_metric = metric;
 141         rt->rt_ticks = ticks;
 142         rt->rt_timer = 0;
 143         rt->rt_flags = RTF_UP | flags;
 144         rt->rt_state = state | RTS_CHANGED;
 145         rt->rt_ifp = if_ifwithnet(&rt->rt_router);
 146         rt->rt_clone = NULL;
 147         if (metric)
 148                 rt->rt_flags |= RTF_GATEWAY;
 149         insque(rt, rh);
 150         TRACE_ACTION("ADD", rt);
 151         /*
 152          * If the ioctl fails because the gateway is unreachable
 153          * from this host, discard the entry.  This should only
 154          * occur because of an incorrect entry in /etc/gateways.
 155          */
 156         if (install && rtioctl(ADD, &rt->rt_rt) < 0) {
 157                 if (errno != EEXIST)
 158                         perror("SIOCADDRT");
 159                 if (errno == ENETUNREACH) {
 160                         TRACE_ACTION("DELETE", rt);
 161                         remque(rt);
 162                         free((char *)rt);
 163                 }
 164         }
 165 }
 166
 167 void
 168 rtadd_clone(struct rt_entry *ort, struct sockaddr *dst, struct sockaddr *gate,
 169             short metric, short ticks, int state)
 170 {
 171         struct afhash h;
 172         struct rt_entry *rt;
 173         struct rthash *rh;
 174         int af = dst->sa_family, flags;
 175         u_int hash;
 176
 177         FIXLEN(dst);
 178         FIXLEN(gate);
 179         if (af >= AF_MAX)
 180                 return;
 181         (*afswitch[af].af_hash)(dst, &h);
 182         flags = (*afswitch[af].af_ishost)(dst) ? RTF_HOST : 0;
 183         hash = h.afh_nethash;
 184         rh = &nethash[hash & ROUTEHASHMASK];
 185         rt = (struct rt_entry *)malloc(sizeof (*rt));
 186         if (rt == 0)
 187                 return;
 188         rt->rt_hash = hash;
 189         rt->rt_dst = *dst;
 190         rt->rt_router = *gate;
 191         rt->rt_metric = metric;
 192         rt->rt_ticks = ticks;
 193         rt->rt_timer = 0;
 194         rt->rt_flags = RTF_UP | flags;
 195         rt->rt_state = state | RTS_CHANGED;
 196         rt->rt_ifp = if_ifwithnet(&rt->rt_router);
 197         rt->rt_clone = NULL;
 198         rt->rt_forw = NULL;
 199         rt->rt_back = NULL;
 200         if (metric)
 201                 rt->rt_flags |= RTF_GATEWAY;
 202
 203         while(ort->rt_clone != NULL)
 204                 ort = ort->rt_clone;
 205         ort->rt_clone = rt;
 206         TRACE_ACTION("ADD_CLONE", rt);
 207 }
 208
 209 void
 210 rtchange(struct rt_entry *rt, struct sockaddr *gate, short metric, short ticks)
 211 {
 212         int doioctl = 0, metricchanged = 0;
 213         struct rtuentry oldroute;
 214
 215         FIXLEN(gate);
 216         /*
 217          * Handling of clones.
 218          * When the route changed and it had clones, handle it special.
 219          * 1. If the new route is cheaper than the clone(s), free the clones.
 220          * 2. If the new route is the same cost, it may be one of the clones,
 221          *    search for it and free it.
 222          * 3. If the new route is more expensive than the clone(s), use the
 223          *    values of the clone(s).
 224          */
 225         if (rt->rt_clone) {
 226                 if ((ticks < rt->rt_clone->rt_ticks) ||
 227                     ((ticks == rt->rt_clone->rt_ticks) &&
 228                      (metric < rt->rt_clone->rt_metric))) {
 229                         /*
 230                          * Free all clones.
 231                          */
 232                         struct rt_entry *trt, *nrt;
 233
 234                         trt = rt->rt_clone;
 235                         rt->rt_clone = NULL;
 236                         while(trt) {
 237                                 nrt = trt->rt_clone;
 238                                 free((char *)trt);
 239                                 trt = nrt;
 240                         }
 241                 } else if ((ticks == rt->rt_clone->rt_ticks) &&
 242                      (metric == rt->rt_clone->rt_metric)) {
 243                         struct rt_entry *prt, *trt;
 244
 245                         prt = rt;
 246                         trt = rt->rt_clone;
 247
 248                         while(trt) {
 249                                 if (equal(&trt->rt_router, gate)) {
 250                                         prt->rt_clone = trt->rt_clone;
 251                                         free(trt);
 252                                         trt = prt->rt_clone;
 253                                 } else {
 254                                         prt = trt;
 255                                         trt = trt->rt_clone;
 256                                 }
 257                         }
 258                 } else {
 259                         /*
 260                          * Use the values of the first clone.
 261                          * Delete the corresponding clone.
 262                          */
 263                         struct rt_entry *trt;
 264
 265                         trt = rt->rt_clone;
 266                         rt->rt_clone = rt->rt_clone->rt_clone;
 267                         metric = trt->rt_metric;
 268                         ticks = trt->rt_ticks;
 269                         *gate = trt->rt_router;
 270                         free((char *)trt);
 271                 }
 272         }
 273
 274         if (!equal(&rt->rt_router, gate))
 275                 doioctl++;
 276         if ((metric != rt->rt_metric) || (ticks != rt->rt_ticks))
 277                 metricchanged++;
 278         if (doioctl || metricchanged) {
 279                 TRACE_ACTION("CHANGE FROM", rt);
 280                 if (doioctl) {
 281                         oldroute = rt->rt_rt;
 282                         rt->rt_router = *gate;
 283                 }
 284                 rt->rt_metric = metric;
 285                 rt->rt_ticks = ticks;
 286                 if ((rt->rt_state & RTS_INTERFACE) && metric) {
 287                         rt->rt_state &= ~RTS_INTERFACE;
 288                         if(rt->rt_ifp)
 289                                 syslog(LOG_ERR,
 290                                 "changing route from interface %s (timed out)",
 291                                 rt->rt_ifp->int_name);
 292                         else
 293                                 syslog(LOG_ERR,
 294                                 "changing route from interface ??? (timed out)");
 295                 }
 296                 if (metric)
 297                         rt->rt_flags |= RTF_GATEWAY;
 298                 else
 299                         rt->rt_flags &= ~RTF_GATEWAY;
 300                 rt->rt_ifp = if_ifwithnet(&rt->rt_router);
 301                 rt->rt_state |= RTS_CHANGED;
 302                 TRACE_ACTION("CHANGE TO", rt);
 303         }
 304         if (doioctl && install) {
 305 #ifndef RTM_ADD
 306                 if (rtioctl(ADD, &rt->rt_rt) < 0)
 307                   syslog(LOG_ERR, "rtioctl ADD dst %s, gw %s: %m",
 308                    ipx_ntoa(&((struct sockaddr_ipx *)&rt->rt_dst)->sipx_addr),
 309                    ipx_ntoa(&((struct sockaddr_ipx *)&rt->rt_router)->sipx_addr));
 310                 if (delete && rtioctl(DELETE, &oldroute) < 0)
 311                         perror("rtioctl DELETE");
 312 #else
 313                 if (delete == 0) {
 314                         if (rtioctl(ADD, &rt->rt_rt) >= 0)
 315                                 return;
 316                 } else {
 317                         if (rtioctl(CHANGE, &rt->rt_rt) >= 0)
 318                                 return;
 319                 }
 320                 syslog(LOG_ERR, "rtioctl ADD dst %s, gw %s: %m",
 321                    ipxdp_ntoa(&((struct sockaddr_ipx *)&rt->rt_dst)->sipx_addr),
 322                    ipxdp_ntoa(&((struct sockaddr_ipx *)&rt->rt_router)->sipx_addr));
 323 #endif
 324         }
 325 }
 326
 327 void
 328 rtdelete(struct rt_entry *rt)
 329 {
 330         struct sockaddr *sa = &(rt->rt_router);
 331
 332         FIXLEN(sa);
 333         sa = &(rt->rt_dst);
 334         FIXLEN(sa);
 335         if (rt->rt_clone) {
 336                 /*
 337                  * If there is a clone we just do a rt_change to it.
 338                  */
 339                 struct rt_entry *trt = rt->rt_clone;
 340                 rtchange(rt, &trt->rt_router, trt->rt_metric, trt->rt_ticks);
 341                 return;
 342         }
 343         if (rt->rt_state & RTS_INTERFACE) {
 344                 if (rt->rt_ifp)
 345                         syslog(LOG_ERR,
 346                                 "deleting route to interface %s (timed out)",
 347                                 rt->rt_ifp->int_name);
 348                 else
 349                         syslog(LOG_ERR,
 350                                 "deleting route to interface ??? (timed out)");
 351         }
 352         TRACE_ACTION("DELETE", rt);
 353         if (install && rtioctl(DELETE, &rt->rt_rt) < 0)
 354                 perror("rtioctl DELETE");
 355         remque(rt);
 356         free((char *)rt);
 357 }
 358
 359 void
 360 rtinit(void)
 361 {
 362         struct rthash *rh;
 363
 364         for (rh = nethash; rh < &nethash[ROUTEHASHSIZ]; rh++)
 365                 rh->rt_forw = rh->rt_back = (struct rt_entry *)rh;
 366 }
 367 int seqno;
 368
 369 int
 370 rtioctl(int action, struct rtuentry *ort)
 371 {
 372 #ifndef RTM_ADD
 373         if (install == 0)
 374                 return (errno = 0);
 375
 376         ort->rtu_rtflags = ort->rtu_flags;
 377
 378         switch (action) {
 379
 380         case ADD:
 381                 return (ioctl(s, SIOCADDRT, (char *)ort));
 382
 383         case DELETE:
 384                 return (ioctl(s, SIOCDELRT, (char *)ort));
 385
 386         default:
 387                 return (-1);
 388         }
 389 #else /* RTM_ADD */
 390         struct {
 391                 struct rt_msghdr w_rtm;
 392                 struct sockaddr w_dst;
 393                 struct sockaddr w_gate;
 394                 struct sockaddr_ipx w_netmask;
 395         } w;
 396 #define rtm w.w_rtm
 397
 398         bzero((char *)&w, sizeof(w));
 399         rtm.rtm_msglen = sizeof(w);
 400         rtm.rtm_version = RTM_VERSION;
 401         rtm.rtm_type = (action == ADD ? RTM_ADD :
 402                                 (action == DELETE ? RTM_DELETE : RTM_CHANGE));
 403         rtm.rtm_flags = ort->rtu_flags;
 404         rtm.rtm_seq = ++seqno;
 405         rtm.rtm_addrs = RTA_DST|RTA_GATEWAY;
 406         bcopy((char *)&ort->rtu_dst, (char *)&w.w_dst, sizeof(w.w_dst));
 407         bcopy((char *)&ort->rtu_router, (char *)&w.w_gate, sizeof(w.w_gate));
 408         w.w_gate.sa_family = w.w_dst.sa_family = AF_IPX;
 409         w.w_gate.sa_len = w.w_dst.sa_len = sizeof(w.w_dst);
 410         if (rtm.rtm_flags & RTF_HOST) {
 411                 rtm.rtm_msglen -= sizeof(w.w_netmask);
 412         } else {
 413                 rtm.rtm_addrs |= RTA_NETMASK;
 414                 w.w_netmask = ipx_netmask;
 415                 rtm.rtm_msglen -= sizeof(w.w_netmask) - ipx_netmask.sipx_len;
 416         }
 417         errno = 0;
 418         return write(r, (char *)&w, rtm.rtm_msglen);
 419 #endif  /* RTM_ADD */
 420 }