eigrpd/eigrp_network.c

   1 /*
   2  * EIGRP Network Related Functions.
   3  * Copyright (C) 2013-2014
   4  * Authors:
   5  *   Donnie Savage
   6  *   Jan Janovic
   7  *   Matej Perina
   8  *   Peter Orsag
   9  *   Peter Paluch
  10  *
  11  * This file is part of GNU Zebra.
  12  *
  13  * GNU Zebra is free software; you can redistribute it and/or modify it
  14  * under the terms of the GNU General Public License as published by the
  15  * Free Software Foundation; either version 2, or (at your option) any
  16  * later version.
  17  *
  18  * GNU Zebra is distributed in the hope that it will be useful, but
  19  * WITHOUT ANY WARRANTY; without even the implied warranty of
  20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  21  * General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU General Public License along
  24  * with this program; see the file COPYING; if not, write to the Free Software
  25  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  26  */
  27
  28 #include <zebra.h>
  29
  30 #include "thread.h"
  31 #include "linklist.h"
  32 #include "prefix.h"
  33 #include "if.h"
  34 #include "sockunion.h"
  35 #include "log.h"
  36 #include "sockopt.h"
  37 #include "privs.h"
  38 #include "table.h"
  39 #include "vty.h"
  40 #include "lib_errors.h"
  41
  42 #include "eigrpd/eigrp_structs.h"
  43 #include "eigrpd/eigrpd.h"
  44 #include "eigrpd/eigrp_interface.h"
  45 #include "eigrpd/eigrp_neighbor.h"
  46 #include "eigrpd/eigrp_packet.h"
  47 #include "eigrpd/eigrp_zebra.h"
  48 #include "eigrpd/eigrp_vty.h"
  49 #include "eigrpd/eigrp_network.h"
  50
  51 static int eigrp_network_match_iface(const struct prefix *connected_prefix,
  52                                      const struct prefix *prefix);
  53 static void eigrp_network_run_interface(struct eigrp *, struct prefix *,
  54                                         struct interface *);
  55
  56 int eigrp_sock_init(void)
  57 {
  58         int eigrp_sock;
  59         int ret;
  60 #ifdef IP_HDRINCL
  61         int hincl = 1;
  62 #endif
  63
  64         frr_elevate_privs(&eigrpd_privs) {
  65                 eigrp_sock = socket(AF_INET, SOCK_RAW, IPPROTO_EIGRPIGP);
  66                 if (eigrp_sock < 0) {
  67                         zlog_err("eigrp_read_sock_init: socket: %s",
  68                                  safe_strerror(errno));
  69                         exit(1);
  70                 }
  71
  72 #ifdef IP_HDRINCL
  73                 /* we will include IP header with packet */
  74                 ret = setsockopt(eigrp_sock, IPPROTO_IP, IP_HDRINCL, &hincl,
  75                                  sizeof(hincl));
  76                 if (ret < 0) {
  77                         zlog_warn("Can't set IP_HDRINCL option for fd %d: %s",
  78                                   eigrp_sock, safe_strerror(errno));
  79                 }
  80 #elif defined(IPTOS_PREC_INTERNETCONTROL)
  81 #warning "IP_HDRINCL not available on this system"
  82 #warning "using IPTOS_PREC_INTERNETCONTROL"
  83                 ret = setsockopt_ipv4_tos(eigrp_sock,
  84                                           IPTOS_PREC_INTERNETCONTROL);
  85                 if (ret < 0) {
  86                         zlog_warn("can't set sockopt IP_TOS %d to socket %d: %s",
  87                                   tos, eigrp_sock, safe_strerror(errno));
  88                         close(eigrp_sock); /* Prevent sd leak. */
  89                         return ret;
  90                 }
  91 #else /* !IPTOS_PREC_INTERNETCONTROL */
  92 #warning "IP_HDRINCL not available, nor is IPTOS_PREC_INTERNETCONTROL"
  93                 zlog_warn("IP_HDRINCL option not available");
  94 #endif /* IP_HDRINCL */
  95
  96                 ret = setsockopt_ifindex(AF_INET, eigrp_sock, 1);
  97                 if (ret < 0)
  98                         zlog_warn("Can't set pktinfo option for fd %d",
  99                                   eigrp_sock);
 100         }
 101
 102         return eigrp_sock;
 103 }
 104
 105 void eigrp_adjust_sndbuflen(struct eigrp *eigrp, unsigned int buflen)
 106 {
 107         int newbuflen;
 108         /* Check if any work has to be done at all. */
 109         if (eigrp->maxsndbuflen >= buflen)
 110                 return;
 111         frr_elevate_privs(&eigrpd_privs) {
 112
 113         /* Now we try to set SO_SNDBUF to what our caller has requested
 114          * (the MTU of a newly added interface). However, if the OS has
 115          * truncated the actual buffer size to somewhat less size, try
 116          * to detect it and update our records appropriately. The OS
 117          * may allocate more buffer space, than requested, this isn't
 118          * a error.
 119          */
 120                 setsockopt_so_sendbuf(eigrp->fd, buflen);
 121                 newbuflen = getsockopt_so_sendbuf(eigrp->fd);
 122                 if (newbuflen < 0 || newbuflen < (int)buflen)
 123                         zlog_warn("%s: tried to set SO_SNDBUF to %u, but got %d",
 124                                   __func__, buflen, newbuflen);
 125                 if (newbuflen >= 0)
 126                         eigrp->maxsndbuflen = (unsigned int)newbuflen;
 127                 else
 128                         zlog_warn("%s: failed to get SO_SNDBUF", __func__);
 129         }
 130 }
 131
 132 int eigrp_if_ipmulticast(struct eigrp *top, struct prefix *p,
 133                          unsigned int ifindex)
 134 {
 135         uint8_t val;
 136         int ret, len;
 137
 138         val = 0;
 139         len = sizeof(val);
 140
 141         /* Prevent receiving self-origined multicast packets. */
 142         ret = setsockopt(top->fd, IPPROTO_IP, IP_MULTICAST_LOOP, (void *)&val,
 143                          len);
 144         if (ret < 0)
 145                 zlog_warn(
 146                         "can't setsockopt IP_MULTICAST_LOOP (0) for fd %d: %s",
 147                         top->fd, safe_strerror(errno));
 148
 149         /* Explicitly set multicast ttl to 1 -- endo. */
 150         val = 1;
 151         ret = setsockopt(top->fd, IPPROTO_IP, IP_MULTICAST_TTL, (void *)&val,
 152                          len);
 153         if (ret < 0)
 154                 zlog_warn("can't setsockopt IP_MULTICAST_TTL (1) for fd %d: %s",
 155                           top->fd, safe_strerror(errno));
 156
 157         ret = setsockopt_ipv4_multicast_if(top->fd, p->u.prefix4, ifindex);
 158         if (ret < 0)
 159                 zlog_warn(
 160                         "can't setsockopt IP_MULTICAST_IF (fd %d, addr %s, "
 161                         "ifindex %u): %s",
 162                         top->fd, inet_ntoa(p->u.prefix4), ifindex,
 163                         safe_strerror(errno));
 164
 165         return ret;
 166 }
 167
 168 /* Join to the EIGRP multicast group. */
 169 int eigrp_if_add_allspfrouters(struct eigrp *top, struct prefix *p,
 170                                unsigned int ifindex)
 171 {
 172         int ret;
 173
 174         ret = setsockopt_ipv4_multicast(
 175                 top->fd, IP_ADD_MEMBERSHIP, p->u.prefix4,
 176                 htonl(EIGRP_MULTICAST_ADDRESS), ifindex);
 177         if (ret < 0)
 178                 zlog_warn(
 179                         "can't setsockopt IP_ADD_MEMBERSHIP (fd %d, addr %s, "
 180                         "ifindex %u, AllSPFRouters): %s; perhaps a kernel limit "
 181                         "on # of multicast group memberships has been exceeded?",
 182                         top->fd, inet_ntoa(p->u.prefix4), ifindex,
 183                         safe_strerror(errno));
 184         else
 185                 zlog_debug("interface %s [%u] join EIGRP Multicast group.",
 186                            inet_ntoa(p->u.prefix4), ifindex);
 187
 188         return ret;
 189 }
 190
 191 int eigrp_if_drop_allspfrouters(struct eigrp *top, struct prefix *p,
 192                                 unsigned int ifindex)
 193 {
 194         int ret;
 195
 196         ret = setsockopt_ipv4_multicast(
 197                 top->fd, IP_DROP_MEMBERSHIP, p->u.prefix4,
 198                 htonl(EIGRP_MULTICAST_ADDRESS), ifindex);
 199         if (ret < 0)
 200                 zlog_warn(
 201                         "can't setsockopt IP_DROP_MEMBERSHIP (fd %d, addr %s, "
 202                         "ifindex %u, AllSPFRouters): %s",
 203                         top->fd, inet_ntoa(p->u.prefix4), ifindex,
 204                         safe_strerror(errno));
 205         else
 206                 zlog_debug("interface %s [%u] leave EIGRP Multicast group.",
 207                            inet_ntoa(p->u.prefix4), ifindex);
 208
 209         return ret;
 210 }
 211
 212 int eigrp_network_set(struct eigrp *eigrp, struct prefix *p)
 213 {
 214         struct vrf *vrf = vrf_lookup_by_id(VRF_DEFAULT);
 215         struct route_node *rn;
 216         struct interface *ifp;
 217
 218         rn = route_node_get(eigrp->networks, (struct prefix *)p);
 219         if (rn->info) {
 220                 /* There is already same network statement. */
 221                 route_unlock_node(rn);
 222                 return 0;
 223         }
 224
 225         struct prefix *pref = prefix_new();
 226         PREFIX_COPY_IPV4(pref, p);
 227         rn->info = (void *)pref;
 228
 229         /* Schedule Router ID Update. */
 230         if (eigrp->router_id == 0)
 231                 eigrp_router_id_update(eigrp);
 232         /* Run network config now. */
 233         /* Get target interface. */
 234         FOR_ALL_INTERFACES (vrf, ifp) {
 235                 zlog_debug("Setting up %s", ifp->name);
 236                 eigrp_network_run_interface(eigrp, p, ifp);
 237         }
 238         return 1;
 239 }
 240
 241 /* Check whether interface matches given network
 242  * returns: 1, true. 0, false
 243  */
 244 static int eigrp_network_match_iface(const struct prefix *co_prefix,
 245                                      const struct prefix *net)
 246 {
 247         /* new approach: more elegant and conceptually clean */
 248         return prefix_match_network_statement(net, co_prefix);
 249 }
 250
 251 static void eigrp_network_run_interface(struct eigrp *eigrp, struct prefix *p,
 252                                         struct interface *ifp)
 253 {
 254         struct eigrp_interface *ei;
 255         struct listnode *cnode;
 256         struct connected *co;
 257
 258         /* if interface prefix is match specified prefix,
 259            then create socket and join multicast group. */
 260         for (ALL_LIST_ELEMENTS_RO(ifp->connected, cnode, co)) {
 261
 262                 if (CHECK_FLAG(co->flags, ZEBRA_IFA_SECONDARY))
 263                         continue;
 264
 265                 if (p->family == co->address->family && !ifp->info
 266                     && eigrp_network_match_iface(co->address, p)) {
 267
 268                         ei = eigrp_if_new(eigrp, ifp, co->address);
 269
 270                         /* Relate eigrp interface to eigrp instance. */
 271                         ei->eigrp = eigrp;
 272
 273                         /* if router_id is not configured, dont bring up
 274                          * interfaces.
 275                          * eigrp_router_id_update() will call eigrp_if_update
 276                          * whenever r-id is configured instead.
 277                          */
 278                         if (if_is_operative(ifp))
 279                                 eigrp_if_up(ei);
 280                 }
 281         }
 282 }
 283
 284 void eigrp_if_update(struct interface *ifp)
 285 {
 286         struct listnode *node, *nnode;
 287         struct route_node *rn;
 288         struct eigrp *eigrp;
 289
 290         /*
 291          * In the event there are multiple eigrp autonymnous systems running,
 292          * we need to check eac one and add the interface as approperate
 293          */
 294         for (ALL_LIST_ELEMENTS(eigrp_om->eigrp, node, nnode, eigrp)) {
 295                 /* EIGRP must be on and Router-ID must be configured. */
 296                 if (!eigrp || eigrp->router_id == 0)
 297                         continue;
 298
 299                 /* Run each network for this interface. */
 300                 for (rn = route_top(eigrp->networks); rn; rn = route_next(rn))
 301                         if (rn->info != NULL) {
 302                                 eigrp_network_run_interface(eigrp, &rn->p, ifp);
 303                         }
 304         }
 305 }
 306
 307 int eigrp_network_unset(struct eigrp *eigrp, struct prefix *p)
 308 {
 309         struct route_node *rn;
 310         struct listnode *node, *nnode;
 311         struct eigrp_interface *ei;
 312         struct prefix *pref;
 313
 314         rn = route_node_lookup(eigrp->networks, p);
 315         if (rn == NULL)
 316                 return 0;
 317
 318         pref = rn->info;
 319         route_unlock_node(rn);
 320
 321         if (!IPV4_ADDR_SAME(&pref->u.prefix4, &p->u.prefix4))
 322                 return 0;
 323
 324         prefix_ipv4_free(rn->info);
 325         rn->info = NULL;
 326         route_unlock_node(rn); /* initial reference */
 327
 328         /* Find interfaces that not configured already.  */
 329         for (ALL_LIST_ELEMENTS(eigrp->eiflist, node, nnode, ei)) {
 330                 bool found = false;
 331
 332                 for (rn = route_top(eigrp->networks); rn; rn = route_next(rn)) {
 333                         if (rn->info == NULL)
 334                                 continue;
 335
 336                         if (eigrp_network_match_iface(ei->address, &rn->p)) {
 337                                 found = true;
 338                                 route_unlock_node(rn);
 339                                 break;
 340                         }
 341                 }
 342
 343                 if (!found) {
 344                         eigrp_if_free(ei, INTERFACE_DOWN_BY_VTY);
 345                 }
 346         }
 347
 348         return 1;
 349 }
 350
 351 uint32_t eigrp_calculate_metrics(struct eigrp *eigrp,
 352                                  struct eigrp_metrics metric)
 353 {
 354         uint64_t temp_metric;
 355         temp_metric = 0;
 356
 357         if (metric.delay == EIGRP_MAX_METRIC)
 358                 return EIGRP_MAX_METRIC;
 359
 360         // EIGRP Metric =
 361         // {K1*BW+[(K2*BW)/(256-load)]+(K3*delay)}*{K5/(reliability+K4)}
 362
 363         if (eigrp->k_values[0])
 364                 temp_metric += (eigrp->k_values[0] * metric.bandwidth);
 365         if (eigrp->k_values[1])
 366                 temp_metric += ((eigrp->k_values[1] * metric.bandwidth)
 367                                 / (256 - metric.load));
 368         if (eigrp->k_values[2])
 369                 temp_metric += (eigrp->k_values[2] * metric.delay);
 370         if (eigrp->k_values[3] && !eigrp->k_values[4])
 371                 temp_metric *= eigrp->k_values[3];
 372         if (!eigrp->k_values[3] && eigrp->k_values[4])
 373                 temp_metric *= (eigrp->k_values[4] / metric.reliability);
 374         if (eigrp->k_values[3] && eigrp->k_values[4])
 375                 temp_metric *= ((eigrp->k_values[4] / metric.reliability)
 376                                 + eigrp->k_values[3]);
 377
 378         if (temp_metric <= EIGRP_MAX_METRIC)
 379                 return (uint32_t)temp_metric;
 380         else
 381                 return EIGRP_MAX_METRIC;
 382 }
 383
 384 uint32_t eigrp_calculate_total_metrics(struct eigrp *eigrp,
 385                                        struct eigrp_nexthop_entry *entry)
 386 {
 387         struct eigrp_interface *ei = entry->ei;
 388
 389         entry->total_metric = entry->reported_metric;
 390         uint64_t temp_delay =
 391                 (uint64_t)entry->total_metric.delay
 392                 + (uint64_t)eigrp_delay_to_scaled(ei->params.delay);
 393         entry->total_metric.delay = temp_delay > EIGRP_MAX_METRIC
 394                                             ? EIGRP_MAX_METRIC
 395                                             : (uint32_t)temp_delay;
 396
 397         uint32_t bw = eigrp_bandwidth_to_scaled(ei->params.bandwidth);
 398         entry->total_metric.bandwidth = entry->total_metric.bandwidth > bw
 399                                                 ? bw
 400                                                 : entry->total_metric.bandwidth;
 401
 402         return eigrp_calculate_metrics(eigrp, entry->total_metric);
 403 }
 404
 405 uint8_t eigrp_metrics_is_same(struct eigrp_metrics metric1,
 406                               struct eigrp_metrics metric2)
 407 {
 408         if ((metric1.bandwidth == metric2.bandwidth)
 409             && (metric1.delay == metric2.delay)
 410             && (metric1.hop_count == metric2.hop_count)
 411             && (metric1.load == metric2.load)
 412             && (metric1.reliability == metric2.reliability)
 413             && (metric1.mtu[0] == metric2.mtu[0])
 414             && (metric1.mtu[1] == metric2.mtu[1])
 415             && (metric1.mtu[2] == metric2.mtu[2]))
 416                 return 1;
 417
 418         return 0; // if different
 419 }
 420
 421 void eigrp_external_routes_refresh(struct eigrp *eigrp, int type)
 422 {
 423 }