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
  41 #include "eigrpd/eigrp_structs.h"
  42 #include "eigrpd/eigrpd.h"
  43 #include "eigrpd/eigrp_interface.h"
  44 #include "eigrpd/eigrp_neighbor.h"
  45 #include "eigrpd/eigrp_packet.h"
  46 #include "eigrpd/eigrp_zebra.h"
  47 #include "eigrpd/eigrp_vty.h"
  48 #include "eigrpd/eigrp_network.h"
  49
  50 static int eigrp_network_match_iface(const struct connected *,
  51                                      const struct prefix *);
  52 static void eigrp_network_run_interface(struct eigrp *, struct prefix *,
  53                                         struct interface *);
  54
  55 int eigrp_sock_init(void)
  56 {
  57         int eigrp_sock;
  58         int ret;
  59 #ifdef IP_HDRINCL
  60         int hincl = 1;
  61 #endif
  62
  63         if (eigrpd_privs.change(ZPRIVS_RAISE))
  64                 zlog_err("eigrp_sock_init: could not raise privs, %s",
  65                          safe_strerror(errno));
  66
  67         eigrp_sock = socket(AF_INET, SOCK_RAW, IPPROTO_EIGRPIGP);
  68         if (eigrp_sock < 0) {
  69                 int save_errno = errno;
  70                 if (eigrpd_privs.change(ZPRIVS_LOWER))
  71                         zlog_err("eigrp_sock_init: could not lower privs, %s",
  72                                  safe_strerror(errno));
  73                 zlog_err("eigrp_read_sock_init: socket: %s",
  74                          safe_strerror(save_errno));
  75                 exit(1);
  76         }
  77
  78 #ifdef IP_HDRINCL
  79         /* we will include IP header with packet */
  80         ret = setsockopt(eigrp_sock, IPPROTO_IP, IP_HDRINCL, &hincl,
  81                          sizeof(hincl));
  82         if (ret < 0) {
  83                 int save_errno = errno;
  84                 if (eigrpd_privs.change(ZPRIVS_LOWER))
  85                         zlog_err("eigrp_sock_init: could not lower privs, %s",
  86                                  safe_strerror(errno));
  87                 zlog_warn("Can't set IP_HDRINCL option for fd %d: %s",
  88                           eigrp_sock, safe_strerror(save_errno));
  89         }
  90 #elif defined(IPTOS_PREC_INTERNETCONTROL)
  91 #warning "IP_HDRINCL not available on this system"
  92 #warning "using IPTOS_PREC_INTERNETCONTROL"
  93         ret = setsockopt_ipv4_tos(eigrp_sock, IPTOS_PREC_INTERNETCONTROL);
  94         if (ret < 0) {
  95                 int save_errno = errno;
  96                 if (eigrpd_privs.change(ZPRIVS_LOWER))
  97                         zlog_err("eigrpd_sock_init: could not lower privs, %s",
  98                                  safe_strerror(errno));
  99                 zlog_warn("can't set sockopt IP_TOS %d to socket %d: %s", tos,
 100                           eigrp_sock, safe_strerror(save_errno));
 101                 close(eigrp_sock); /* Prevent sd leak. */
 102                 return ret;
 103         }
 104 #else /* !IPTOS_PREC_INTERNETCONTROL */
 105 #warning "IP_HDRINCL not available, nor is IPTOS_PREC_INTERNETCONTROL"
 106         zlog_warn("IP_HDRINCL option not available");
 107 #endif /* IP_HDRINCL */
 108
 109         ret = setsockopt_ifindex(AF_INET, eigrp_sock, 1);
 110
 111         if (ret < 0)
 112                 zlog_warn("Can't set pktinfo option for fd %d", eigrp_sock);
 113
 114         if (eigrpd_privs.change(ZPRIVS_LOWER)) {
 115                 zlog_err("eigrp_sock_init: could not lower privs, %s",
 116                          safe_strerror(errno));
 117         }
 118
 119         return eigrp_sock;
 120 }
 121
 122 void eigrp_adjust_sndbuflen(struct eigrp *eigrp, unsigned int buflen)
 123 {
 124         int newbuflen;
 125         /* Check if any work has to be done at all. */
 126         if (eigrp->maxsndbuflen >= buflen)
 127                 return;
 128         if (eigrpd_privs.change(ZPRIVS_RAISE))
 129                 zlog_err("%s: could not raise privs, %s", __func__,
 130                          safe_strerror(errno));
 131
 132         /* Now we try to set SO_SNDBUF to what our caller has requested
 133          * (the MTU of a newly added interface). However, if the OS has
 134          * truncated the actual buffer size to somewhat less size, try
 135          * to detect it and update our records appropriately. The OS
 136          * may allocate more buffer space, than requested, this isn't
 137          * a error.
 138          */
 139         setsockopt_so_sendbuf(eigrp->fd, buflen);
 140         newbuflen = getsockopt_so_sendbuf(eigrp->fd);
 141         if (newbuflen < 0 || newbuflen < (int)buflen)
 142                 zlog_warn("%s: tried to set SO_SNDBUF to %u, but got %d",
 143                           __func__, buflen, newbuflen);
 144         if (newbuflen >= 0)
 145                 eigrp->maxsndbuflen = (unsigned int)newbuflen;
 146         else
 147                 zlog_warn("%s: failed to get SO_SNDBUF", __func__);
 148         if (eigrpd_privs.change(ZPRIVS_LOWER))
 149                 zlog_err("%s: could not lower privs, %s", __func__,
 150                          safe_strerror(errno));
 151 }
 152
 153 int eigrp_if_ipmulticast(struct eigrp *top, struct prefix *p,
 154                          unsigned int ifindex)
 155 {
 156         uint8_t val;
 157         int ret, len;
 158
 159         val = 0;
 160         len = sizeof(val);
 161
 162         /* Prevent receiving self-origined multicast packets. */
 163         ret = setsockopt(top->fd, IPPROTO_IP, IP_MULTICAST_LOOP, (void *)&val,
 164                          len);
 165         if (ret < 0)
 166                 zlog_warn(
 167                         "can't setsockopt IP_MULTICAST_LOOP (0) for fd %d: %s",
 168                         top->fd, safe_strerror(errno));
 169
 170         /* Explicitly set multicast ttl to 1 -- endo. */
 171         val = 1;
 172         ret = setsockopt(top->fd, IPPROTO_IP, IP_MULTICAST_TTL, (void *)&val,
 173                          len);
 174         if (ret < 0)
 175                 zlog_warn("can't setsockopt IP_MULTICAST_TTL (1) for fd %d: %s",
 176                           top->fd, safe_strerror(errno));
 177
 178         ret = setsockopt_ipv4_multicast_if(top->fd, p->u.prefix4, ifindex);
 179         if (ret < 0)
 180                 zlog_warn(
 181                         "can't setsockopt IP_MULTICAST_IF (fd %d, addr %s, "
 182                         "ifindex %u): %s",
 183                         top->fd, inet_ntoa(p->u.prefix4), ifindex,
 184                         safe_strerror(errno));
 185
 186         return ret;
 187 }
 188
 189 /* Join to the EIGRP multicast group. */
 190 int eigrp_if_add_allspfrouters(struct eigrp *top, struct prefix *p,
 191                                unsigned int ifindex)
 192 {
 193         int ret;
 194
 195         ret = setsockopt_ipv4_multicast(
 196                 top->fd, IP_ADD_MEMBERSHIP, p->u.prefix4,
 197                 htonl(EIGRP_MULTICAST_ADDRESS), ifindex);
 198         if (ret < 0)
 199                 zlog_warn(
 200                         "can't setsockopt IP_ADD_MEMBERSHIP (fd %d, addr %s, "
 201                         "ifindex %u, AllSPFRouters): %s; perhaps a kernel limit "
 202                         "on # of multicast group memberships has been exceeded?",
 203                         top->fd, inet_ntoa(p->u.prefix4), ifindex,
 204                         safe_strerror(errno));
 205         else
 206                 zlog_debug("interface %s [%u] join EIGRP Multicast group.",
 207                            inet_ntoa(p->u.prefix4), ifindex);
 208
 209         return ret;
 210 }
 211
 212 int eigrp_if_drop_allspfrouters(struct eigrp *top, struct prefix *p,
 213                                 unsigned int ifindex)
 214 {
 215         int ret;
 216
 217         ret = setsockopt_ipv4_multicast(
 218                 top->fd, IP_DROP_MEMBERSHIP, p->u.prefix4,
 219                 htonl(EIGRP_MULTICAST_ADDRESS), ifindex);
 220         if (ret < 0)
 221                 zlog_warn(
 222                         "can't setsockopt IP_DROP_MEMBERSHIP (fd %d, addr %s, "
 223                         "ifindex %u, AllSPFRouters): %s",
 224                         top->fd, inet_ntoa(p->u.prefix4), ifindex,
 225                         safe_strerror(errno));
 226         else
 227                 zlog_debug("interface %s [%u] leave EIGRP Multicast group.",
 228                            inet_ntoa(p->u.prefix4), ifindex);
 229
 230         return ret;
 231 }
 232
 233 int eigrp_network_set(struct eigrp *eigrp, struct prefix *p)
 234 {
 235         struct vrf *vrf = vrf_lookup_by_id(VRF_DEFAULT);
 236         struct route_node *rn;
 237         struct interface *ifp;
 238
 239         rn = route_node_get(eigrp->networks, (struct prefix *)p);
 240         if (rn->info) {
 241                 /* There is already same network statement. */
 242                 route_unlock_node(rn);
 243                 return 0;
 244         }
 245
 246         struct prefix *pref = prefix_new();
 247         PREFIX_COPY_IPV4(pref, p);
 248         rn->info = (void *)pref;
 249
 250         /* Schedule Router ID Update. */
 251         if (eigrp->router_id == 0)
 252                 eigrp_router_id_update(eigrp);
 253         /* Run network config now. */
 254         /* Get target interface. */
 255         FOR_ALL_INTERFACES (vrf, ifp) {
 256                 zlog_debug("Setting up %s", ifp->name);
 257                 eigrp_network_run_interface(eigrp, p, ifp);
 258         }
 259         return 1;
 260 }
 261
 262 /* Check whether interface matches given network
 263  * returns: 1, true. 0, false
 264  */
 265 static int eigrp_network_match_iface(const struct connected *co,
 266                                      const struct prefix *net)
 267 {
 268         /* new approach: more elegant and conceptually clean */
 269         return prefix_match_network_statement(net, CONNECTED_PREFIX(co));
 270 }
 271
 272 static void eigrp_network_run_interface(struct eigrp *eigrp, struct prefix *p,
 273                                         struct interface *ifp)
 274 {
 275         struct eigrp_interface *ei;
 276         struct listnode *cnode;
 277         struct connected *co;
 278
 279         /* if interface prefix is match specified prefix,
 280            then create socket and join multicast group. */
 281         for (ALL_LIST_ELEMENTS_RO(ifp->connected, cnode, co)) {
 282
 283                 if (CHECK_FLAG(co->flags, ZEBRA_IFA_SECONDARY))
 284                         continue;
 285
 286                 if (p->family == co->address->family && !ifp->info
 287                     && eigrp_network_match_iface(co, p)) {
 288
 289                         ei = eigrp_if_new(eigrp, ifp, co->address);
 290                         ei->connected = co;
 291
 292                         /* Relate eigrp interface to eigrp instance. */
 293                         ei->eigrp = eigrp;
 294
 295                         /* if router_id is not configured, dont bring up
 296                          * interfaces.
 297                          * eigrp_router_id_update() will call eigrp_if_update
 298                          * whenever r-id is configured instead.
 299                          */
 300                         if (if_is_operative(ifp))
 301                                 eigrp_if_up(ei);
 302                 }
 303         }
 304 }
 305
 306 void eigrp_if_update(struct interface *ifp)
 307 {
 308         struct listnode *node, *nnode;
 309         struct route_node *rn;
 310         struct eigrp *eigrp;
 311
 312         /*
 313          * In the event there are multiple eigrp autonymnous systems running,
 314          * we need to check eac one and add the interface as approperate
 315          */
 316         for (ALL_LIST_ELEMENTS(eigrp_om->eigrp, node, nnode, eigrp)) {
 317                 /* EIGRP must be on and Router-ID must be configured. */
 318                 if (!eigrp || eigrp->router_id == 0)
 319                         continue;
 320
 321                 /* Run each network for this interface. */
 322                 for (rn = route_top(eigrp->networks); rn; rn = route_next(rn))
 323                         if (rn->info != NULL) {
 324                                 eigrp_network_run_interface(eigrp, &rn->p, ifp);
 325                         }
 326         }
 327 }
 328
 329 int eigrp_network_unset(struct eigrp *eigrp, struct prefix *p)
 330 {
 331         struct route_node *rn;
 332         struct listnode *node, *nnode;
 333         struct eigrp_interface *ei;
 334         struct prefix *pref;
 335
 336         rn = route_node_lookup(eigrp->networks, p);
 337         if (rn == NULL)
 338                 return 0;
 339
 340         pref = rn->info;
 341         route_unlock_node(rn);
 342
 343         if (!IPV4_ADDR_SAME(&pref->u.prefix4, &p->u.prefix4))
 344                 return 0;
 345
 346         prefix_ipv4_free(rn->info);
 347         rn->info = NULL;
 348         route_unlock_node(rn); /* initial reference */
 349
 350         /* Find interfaces that not configured already.  */
 351         for (ALL_LIST_ELEMENTS(eigrp->eiflist, node, nnode, ei)) {
 352                 int found = 0;
 353                 struct connected *co = ei->connected;
 354
 355                 for (rn = route_top(eigrp->networks); rn; rn = route_next(rn)) {
 356                         if (rn->info == NULL)
 357                                 continue;
 358
 359                         if (eigrp_network_match_iface(co, &rn->p)) {
 360                                 found = 1;
 361                                 route_unlock_node(rn);
 362                                 break;
 363                         }
 364                 }
 365
 366                 if (found == 0) {
 367                         eigrp_if_free(ei, INTERFACE_DOWN_BY_VTY);
 368                 }
 369         }
 370
 371         return 1;
 372 }
 373
 374 uint32_t eigrp_calculate_metrics(struct eigrp *eigrp,
 375                                  struct eigrp_metrics metric)
 376 {
 377         uint64_t temp_metric;
 378         temp_metric = 0;
 379
 380         if (metric.delay == EIGRP_MAX_METRIC)
 381                 return EIGRP_MAX_METRIC;
 382
 383         // EIGRP Metric =
 384         // {K1*BW+[(K2*BW)/(256-load)]+(K3*delay)}*{K5/(reliability+K4)}
 385
 386         if (eigrp->k_values[0])
 387                 temp_metric += (eigrp->k_values[0] * metric.bandwidth);
 388         if (eigrp->k_values[1])
 389                 temp_metric += ((eigrp->k_values[1] * metric.bandwidth)
 390                                 / (256 - metric.load));
 391         if (eigrp->k_values[2])
 392                 temp_metric += (eigrp->k_values[2] * metric.delay);
 393         if (eigrp->k_values[3] && !eigrp->k_values[4])
 394                 temp_metric *= eigrp->k_values[3];
 395         if (!eigrp->k_values[3] && eigrp->k_values[4])
 396                 temp_metric *= (eigrp->k_values[4] / metric.reliability);
 397         if (eigrp->k_values[3] && eigrp->k_values[4])
 398                 temp_metric *= ((eigrp->k_values[4] / metric.reliability)
 399                                 + eigrp->k_values[3]);
 400
 401         if (temp_metric <= EIGRP_MAX_METRIC)
 402                 return (uint32_t)temp_metric;
 403         else
 404                 return EIGRP_MAX_METRIC;
 405 }
 406
 407 uint32_t eigrp_calculate_total_metrics(struct eigrp *eigrp,
 408                                        struct eigrp_nexthop_entry *entry)
 409 {
 410         struct eigrp_interface *ei = entry->ei;
 411
 412         entry->total_metric = entry->reported_metric;
 413         uint64_t temp_delay =
 414                 (uint64_t)entry->total_metric.delay
 415                 + (uint64_t)eigrp_delay_to_scaled(ei->params.delay);
 416         entry->total_metric.delay = temp_delay > EIGRP_MAX_METRIC
 417                                             ? EIGRP_MAX_METRIC
 418                                             : (uint32_t)temp_delay;
 419
 420         uint32_t bw = eigrp_bandwidth_to_scaled(ei->params.bandwidth);
 421         entry->total_metric.bandwidth = entry->total_metric.bandwidth > bw
 422                                                 ? bw
 423                                                 : entry->total_metric.bandwidth;
 424
 425         return eigrp_calculate_metrics(eigrp, entry->total_metric);
 426 }
 427
 428 uint8_t eigrp_metrics_is_same(struct eigrp_metrics metric1,
 429                               struct eigrp_metrics metric2)
 430 {
 431         if ((metric1.bandwidth == metric2.bandwidth)
 432             && (metric1.delay == metric2.delay)
 433             && (metric1.hop_count == metric2.hop_count)
 434             && (metric1.load == metric2.load)
 435             && (metric1.reliability == metric2.reliability)
 436             && (metric1.mtu[0] == metric2.mtu[0])
 437             && (metric1.mtu[1] == metric2.mtu[1])
 438             && (metric1.mtu[2] == metric2.mtu[2]))
 439                 return 1;
 440
 441         return 0; // if different
 442 }
 443
 444 void eigrp_external_routes_refresh(struct eigrp *eigrp, int type)
 445 {
 446 }