src/libhydra/plugins/kernel_netlink/kernel_netlink_net.c

   1 /*
   2  * Copyright (C) 2008-2012 Tobias Brunner
   3  * Copyright (C) 2005-2008 Martin Willi
   4  * Hochschule fuer Technik Rapperswil
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License as published by the
   8  * Free Software Foundation; either version 2 of the License, or (at your
   9  * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
  10  *
  11  * This program is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  13  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * for more details.
  15  */
  16
  17 /*
  18  * Copyright (C) 2010 secunet Security Networks AG
  19  * Copyright (C) 2010 Thomas Egerer
  20  *
  21  * Permission is hereby granted, free of charge, to any person obtaining a copy
  22  * of this software and associated documentation files (the "Software"), to deal
  23  * in the Software without restriction, including without limitation the rights
  24  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  25  * copies of the Software, and to permit persons to whom the Software is
  26  * furnished to do so, subject to the following conditions:
  27  *
  28  * The above copyright notice and this permission notice shall be included in
  29  * all copies or substantial portions of the Software.
  30  *
  31  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  32  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  33  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  34  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  35  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  36  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  37  * THE SOFTWARE.
  38  */
  39
  40 #include <sys/socket.h>
  41 #include <sys/utsname.h>
  42 #include <linux/netlink.h>
  43 #include <linux/rtnetlink.h>
  44 #include <unistd.h>
  45 #include <errno.h>
  46 #include <net/if.h>
  47
  48 #include "kernel_netlink_net.h"
  49 #include "kernel_netlink_shared.h"
  50
  51 #include <hydra.h>
  52 #include <debug.h>
  53 #include <threading/thread.h>
  54 #include <threading/condvar.h>
  55 #include <threading/mutex.h>
  56 #include <utils/hashtable.h>
  57 #include <utils/linked_list.h>
  58 #include <processing/jobs/callback_job.h>
  59
  60 /** delay before firing roam events (ms) */
  61 #define ROAM_DELAY 100
  62
  63 /** delay before reinstalling routes (ms) */
  64 #define ROUTE_DELAY 100
  65
  66 typedef struct addr_entry_t addr_entry_t;
  67
  68 /**
  69  * IP address in an inface_entry_t
  70  */
  71 struct addr_entry_t {
  72
  73         /** The ip address */
  74         host_t *ip;
  75
  76         /** virtual IP managed by us */
  77         bool virtual;
  78
  79         /** scope of the address */
  80         u_char scope;
  81
  82         /** Number of times this IP is used, if virtual */
  83         u_int refcount;
  84 };
  85
  86 /**
  87  * destroy a addr_entry_t object
  88  */
  89 static void addr_entry_destroy(addr_entry_t *this)
  90 {
  91         this->ip->destroy(this->ip);
  92         free(this);
  93 }
  94
  95 typedef struct iface_entry_t iface_entry_t;
  96
  97 /**
  98  * A network interface on this system, containing addr_entry_t's
  99  */
 100 struct iface_entry_t {
 101
 102         /** interface index */
 103         int ifindex;
 104
 105         /** name of the interface */
 106         char ifname[IFNAMSIZ];
 107
 108         /** interface flags, as in netdevice(7) SIOCGIFFLAGS */
 109         u_int flags;
 110
 111         /** list of addresses as host_t */
 112         linked_list_t *addrs;
 113
 114         /** TRUE if usable by config */
 115         bool usable;
 116 };
 117
 118 /**
 119  * destroy an interface entry
 120  */
 121 static void iface_entry_destroy(iface_entry_t *this)
 122 {
 123         this->addrs->destroy_function(this->addrs, (void*)addr_entry_destroy);
 124         free(this);
 125 }
 126
 127 /**
 128  * find an interface entry by index
 129  */
 130 static bool iface_entry_by_index(iface_entry_t *this, int *ifindex)
 131 {
 132         return this->ifindex == *ifindex;
 133 }
 134
 135 /**
 136  * check if an interface is up and usable
 137  */
 138 static inline bool iface_entry_up_and_usable(iface_entry_t *iface)
 139 {
 140         return iface->usable && (iface->flags & IFF_UP) == IFF_UP;
 141 }
 142
 143 typedef struct route_entry_t route_entry_t;
 144
 145 /**
 146  * Installed routing entry
 147  */
 148 struct route_entry_t {
 149         /** Name of the interface the route is bound to */
 150         char *if_name;
 151
 152         /** Source ip of the route */
 153         host_t *src_ip;
 154
 155         /** Gateway for this route */
 156         host_t *gateway;
 157
 158         /** Destination net */
 159         chunk_t dst_net;
 160
 161         /** Destination net prefixlen */
 162         u_int8_t prefixlen;
 163 };
 164
 165 /**
 166  * Clone a route_entry_t object.
 167  */
 168 static route_entry_t *route_entry_clone(route_entry_t *this)
 169 {
 170         route_entry_t *route;
 171
 172         INIT(route,
 173                 .if_name = strdup(this->if_name),
 174                 .src_ip = this->src_ip->clone(this->src_ip),
 175                 .gateway = this->gateway->clone(this->gateway),
 176                 .dst_net = chunk_clone(this->dst_net),
 177                 .prefixlen = this->prefixlen,
 178         );
 179         return route;
 180 }
 181
 182 /**
 183  * Destroy a route_entry_t object
 184  */
 185 static void route_entry_destroy(route_entry_t *this)
 186 {
 187         free(this->if_name);
 188         DESTROY_IF(this->src_ip);
 189         DESTROY_IF(this->gateway);
 190         chunk_free(&this->dst_net);
 191         free(this);
 192 }
 193
 194 /**
 195  * Hash a route_entry_t object
 196  */
 197 static u_int route_entry_hash(route_entry_t *this)
 198 {
 199         return chunk_hash_inc(chunk_from_thing(this->prefixlen),
 200                                                   chunk_hash(this->dst_net));
 201 }
 202
 203 /**
 204  * Compare two route_entry_t objects
 205  */
 206 static bool route_entry_equals(route_entry_t *a, route_entry_t *b)
 207 {
 208         return a->if_name && b->if_name && streq(a->if_name, b->if_name) &&
 209                    a->src_ip->ip_equals(a->src_ip, b->src_ip) &&
 210                    a->gateway->ip_equals(a->gateway, b->gateway) &&
 211                    chunk_equals(a->dst_net, b->dst_net) && a->prefixlen == b->prefixlen;
 212 }
 213
 214 typedef struct net_change_t net_change_t;
 215
 216 /**
 217  * Queued network changes
 218  */
 219 struct net_change_t {
 220         /** Name of the interface that got activated (or an IP appeared on) */
 221         char *if_name;
 222 };
 223
 224 /**
 225  * Destroy a net_change_t object
 226  */
 227 static void net_change_destroy(net_change_t *this)
 228 {
 229         free(this->if_name);
 230         free(this);
 231 }
 232
 233 /**
 234  * Hash a net_change_t object
 235  */
 236 static u_int net_change_hash(net_change_t *this)
 237 {
 238         return chunk_hash(chunk_create(this->if_name, strlen(this->if_name)));
 239 }
 240
 241 /**
 242  * Compare two net_change_t objects
 243  */
 244 static bool net_change_equals(net_change_t *a, net_change_t *b)
 245 {
 246         return streq(a->if_name, b->if_name);
 247 }
 248
 249 typedef struct private_kernel_netlink_net_t private_kernel_netlink_net_t;
 250
 251 /**
 252  * Private variables and functions of kernel_netlink_net class.
 253  */
 254 struct private_kernel_netlink_net_t {
 255         /**
 256          * Public part of the kernel_netlink_net_t object.
 257          */
 258         kernel_netlink_net_t public;
 259
 260         /**
 261          * mutex to lock access to various lists
 262          */
 263         mutex_t *mutex;
 264
 265         /**
 266          * condition variable to signal virtual IP add/removal
 267          */
 268         condvar_t *condvar;
 269
 270         /**
 271          * Cached list of interfaces and its addresses (iface_entry_t)
 272          */
 273         linked_list_t *ifaces;
 274
 275         /**
 276          * netlink rt socket (routing)
 277          */
 278         netlink_socket_t *socket;
 279
 280         /**
 281          * Netlink rt socket to receive address change events
 282          */
 283         int socket_events;
 284
 285         /**
 286          * time of the last roam event
 287          */
 288         timeval_t last_roam;
 289
 290         /**
 291          * routing table to install routes
 292          */
 293         int routing_table;
 294
 295         /**
 296          * priority of used routing table
 297          */
 298         int routing_table_prio;
 299
 300         /**
 301          * installed routes
 302          */
 303         hashtable_t *routes;
 304
 305         /**
 306          * interface changes which may trigger route reinstallation
 307          */
 308         hashtable_t *net_changes;
 309
 310         /**
 311          * mutex for route reinstallation triggers
 312          */
 313         mutex_t *net_changes_lock;
 314
 315         /**
 316          * time of last route reinstallation
 317          */
 318         timeval_t last_route_reinstall;
 319
 320         /**
 321          * whether to react to RTM_NEWROUTE or RTM_DELROUTE events
 322          */
 323         bool process_route;
 324
 325         /**
 326          * whether to actually install virtual IPs
 327          */
 328         bool install_virtual_ip;
 329
 330         /**
 331          * whether preferred source addresses can be specified for IPv6 routes
 332          */
 333         bool rta_prefsrc_for_ipv6;
 334
 335         /**
 336          * list with routing tables to be excluded from route lookup
 337          */
 338         linked_list_t *rt_exclude;
 339 };
 340
 341 /**
 342  * Forward declaration
 343  */
 344 static status_t manage_srcroute(private_kernel_netlink_net_t *this,
 345                                                                 int nlmsg_type, int flags, chunk_t dst_net,
 346                                                                 u_int8_t prefixlen, host_t *gateway,
 347                                                                 host_t *src_ip, char *if_name);
 348
 349 /**
 350  * Clear the queued network changes.
 351  */
 352 static void net_changes_clear(private_kernel_netlink_net_t *this)
 353 {
 354         enumerator_t *enumerator;
 355         net_change_t *change;
 356
 357         enumerator = this->net_changes->create_enumerator(this->net_changes);
 358         while (enumerator->enumerate(enumerator, NULL, (void**)&change))
 359         {
 360                 this->net_changes->remove_at(this->net_changes, enumerator);
 361                 net_change_destroy(change);
 362         }
 363         enumerator->destroy(enumerator);
 364 }
 365
 366 /**
 367  * Act upon queued network changes.
 368  */
 369 static job_requeue_t reinstall_routes(private_kernel_netlink_net_t *this)
 370 {
 371         enumerator_t *enumerator;
 372         route_entry_t *route;
 373
 374         this->net_changes_lock->lock(this->net_changes_lock);
 375         this->mutex->lock(this->mutex);
 376
 377         enumerator = this->routes->create_enumerator(this->routes);
 378         while (enumerator->enumerate(enumerator, NULL, (void**)&route))
 379         {
 380                 net_change_t *change, lookup = {
 381                         .if_name = route->if_name,
 382                 };
 383                 /* check if a change for the outgoing interface is queued */
 384                 change = this->net_changes->get(this->net_changes, &lookup);
 385                 if (!change)
 386                 {       /* in case src_ip is not on the outgoing interface */
 387                         if (this->public.interface.get_interface(&this->public.interface,
 388                                                                                                 route->src_ip, &lookup.if_name))
 389                         {
 390                                 if (!streq(lookup.if_name, route->if_name))
 391                                 {
 392                                         change = this->net_changes->get(this->net_changes, &lookup);
 393                                 }
 394                                 free(lookup.if_name);
 395                         }
 396                 }
 397                 if (change)
 398                 {
 399                         manage_srcroute(this, RTM_NEWROUTE, NLM_F_CREATE | NLM_F_EXCL,
 400                                                         route->dst_net, route->prefixlen, route->gateway,
 401                                                         route->src_ip, route->if_name);
 402                 }
 403         }
 404         enumerator->destroy(enumerator);
 405         this->mutex->unlock(this->mutex);
 406
 407         net_changes_clear(this);
 408         this->net_changes_lock->unlock(this->net_changes_lock);
 409         return JOB_REQUEUE_NONE;
 410 }
 411
 412 /**
 413  * Queue route reinstallation caused by network changes for a given interface.
 414  *
 415  * The route reinstallation is delayed for a while and only done once for
 416  * several calls during this delay, in order to avoid doing it too often.
 417  * The interface name is freed.
 418  */
 419 static void queue_route_reinstall(private_kernel_netlink_net_t *this,
 420                                                                   char *if_name)
 421 {
 422         net_change_t *update, *found;
 423         timeval_t now;
 424         job_t *job;
 425
 426         INIT(update,
 427                 .if_name = if_name
 428         );
 429
 430         this->net_changes_lock->lock(this->net_changes_lock);
 431         found = this->net_changes->put(this->net_changes, update, update);
 432         if (found)
 433         {
 434                 net_change_destroy(found);
 435         }
 436         time_monotonic(&now);
 437         if (timercmp(&now, &this->last_route_reinstall, >))
 438         {
 439                 now.tv_usec += ROUTE_DELAY * 1000;
 440                 while (now.tv_usec > 1000000)
 441                 {
 442                         now.tv_sec++;
 443                         now.tv_usec -= 1000000;
 444                 }
 445                 this->last_route_reinstall = now;
 446
 447                 job = (job_t*)callback_job_create((callback_job_cb_t)reinstall_routes,
 448                                                                                   this, NULL, NULL);
 449                 lib->scheduler->schedule_job_ms(lib->scheduler, job, ROUTE_DELAY);
 450         }
 451         this->net_changes_lock->unlock(this->net_changes_lock);
 452 }
 453
 454 /**
 455  * get the refcount of a virtual ip
 456  */
 457 static int get_vip_refcount(private_kernel_netlink_net_t *this, host_t* ip)
 458 {
 459         enumerator_t *ifaces, *addrs;
 460         iface_entry_t *iface;
 461         addr_entry_t *addr;
 462         int refcount = 0;
 463
 464         ifaces = this->ifaces->create_enumerator(this->ifaces);
 465         while (ifaces->enumerate(ifaces, (void**)&iface))
 466         {
 467                 addrs = iface->addrs->create_enumerator(iface->addrs);
 468                 while (addrs->enumerate(addrs, (void**)&addr))
 469                 {
 470                         if (addr->virtual && (iface->flags & IFF_UP) &&
 471                                 ip->ip_equals(ip, addr->ip))
 472                         {
 473                                 refcount = addr->refcount;
 474                                 break;
 475                         }
 476                 }
 477                 addrs->destroy(addrs);
 478                 if (refcount)
 479                 {
 480                         break;
 481                 }
 482         }
 483         ifaces->destroy(ifaces);
 484
 485         return refcount;
 486 }
 487
 488 /**
 489  * get the first non-virtual ip address on the given interface.
 490  * if a candidate address is given, we first search for that address and if not
 491  * found return the address as above.
 492  * returned host is a clone, has to be freed by caller.
 493  */
 494 static host_t *get_interface_address(private_kernel_netlink_net_t *this,
 495                                                                          int ifindex, int family, host_t *candidate)
 496 {
 497         enumerator_t *ifaces, *addrs;
 498         iface_entry_t *iface;
 499         addr_entry_t *addr;
 500         host_t *ip = NULL;
 501
 502         this->mutex->lock(this->mutex);
 503         ifaces = this->ifaces->create_enumerator(this->ifaces);
 504         while (ifaces->enumerate(ifaces, &iface))
 505         {
 506                 if (iface->ifindex == ifindex)
 507                 {
 508                         if (!iface->usable)
 509                         {       /* ignore interfaces excluded by config */
 510                                 break;
 511                         }
 512                         addrs = iface->addrs->create_enumerator(iface->addrs);
 513                         while (addrs->enumerate(addrs, &addr))
 514                         {
 515                                 if (addr->virtual)
 516                                 {
 517                                         continue;
 518                                 }
 519                                 if (addr->ip->get_family(addr->ip) == family)
 520                                 {
 521                                         if (!candidate || candidate->ip_equals(candidate, addr->ip))
 522                                         {       /* stop at the first address if we don't search for a
 523                                                  * candidate or if the candidate matches */
 524                                                 ip = addr->ip;
 525                                                 break;
 526                                         }
 527                                         else if (!ip)
 528                                         {       /* store the first address as fallback if candidate is
 529                                                  * not found */
 530                                                 ip = addr->ip;
 531                                         }
 532                                 }
 533                         }
 534                         addrs->destroy(addrs);
 535                         break;
 536                 }
 537         }
 538         ifaces->destroy(ifaces);
 539         if (ip)
 540         {
 541                 ip = ip->clone(ip);
 542         }
 543         this->mutex->unlock(this->mutex);
 544         return ip;
 545 }
 546
 547 /**
 548  * callback function that raises the delayed roam event
 549  */
 550 static job_requeue_t roam_event(uintptr_t address)
 551 {
 552         hydra->kernel_interface->roam(hydra->kernel_interface, address != 0);
 553         return JOB_REQUEUE_NONE;
 554 }
 555
 556 /**
 557  * fire a roaming event. we delay it for a bit and fire only one event
 558  * for multiple calls. otherwise we would create too many events.
 559  */
 560 static void fire_roam_event(private_kernel_netlink_net_t *this, bool address)
 561 {
 562         timeval_t now;
 563         job_t *job;
 564
 565         time_monotonic(&now);
 566         if (timercmp(&now, &this->last_roam, >))
 567         {
 568                 now.tv_usec += ROAM_DELAY * 1000;
 569                 while (now.tv_usec > 1000000)
 570                 {
 571                         now.tv_sec++;
 572                         now.tv_usec -= 1000000;
 573                 }
 574                 this->last_roam = now;
 575
 576                 job = (job_t*)callback_job_create((callback_job_cb_t)roam_event,
 577                                                                                   (void*)(uintptr_t)(address ? 1 : 0),
 578                                                                                   NULL, NULL);
 579                 lib->scheduler->schedule_job_ms(lib->scheduler, job, ROAM_DELAY);
 580         }
 581 }
 582
 583 /**
 584  * check if an interface with a given index is up and usable
 585  */
 586 static bool is_interface_up_and_usable(private_kernel_netlink_net_t *this,
 587                                                                            int index)
 588 {
 589         iface_entry_t *iface;
 590
 591         if (this->ifaces->find_first(this->ifaces, (void*)iface_entry_by_index,
 592                                                                  (void**)&iface, &index) == SUCCESS)
 593         {
 594                 return iface_entry_up_and_usable(iface);
 595         }
 596         return FALSE;
 597 }
 598
 599 /**
 600  * process RTM_NEWLINK/RTM_DELLINK from kernel
 601  */
 602 static void process_link(private_kernel_netlink_net_t *this,
 603                                                  struct nlmsghdr *hdr, bool event)
 604 {
 605         struct ifinfomsg* msg = (struct ifinfomsg*)(NLMSG_DATA(hdr));
 606         struct rtattr *rta = IFLA_RTA(msg);
 607         size_t rtasize = IFLA_PAYLOAD (hdr);
 608         enumerator_t *enumerator;
 609         iface_entry_t *current, *entry = NULL;
 610         char *name = NULL;
 611         bool update = FALSE, update_routes = FALSE;
 612
 613         while (RTA_OK(rta, rtasize))
 614         {
 615                 switch (rta->rta_type)
 616                 {
 617                         case IFLA_IFNAME:
 618                                 name = RTA_DATA(rta);
 619                                 break;
 620                 }
 621                 rta = RTA_NEXT(rta, rtasize);
 622         }
 623         if (!name)
 624         {
 625                 name = "(unknown)";
 626         }
 627
 628         this->mutex->lock(this->mutex);
 629         switch (hdr->nlmsg_type)
 630         {
 631                 case RTM_NEWLINK:
 632                 {
 633                         enumerator = this->ifaces->create_enumerator(this->ifaces);
 634                         while (enumerator->enumerate(enumerator, &current))
 635                         {
 636                                 if (current->ifindex == msg->ifi_index)
 637                                 {
 638                                         entry = current;
 639                                         break;
 640                                 }
 641                         }
 642                         enumerator->destroy(enumerator);
 643                         if (!entry)
 644                         {
 645                                 entry = malloc_thing(iface_entry_t);
 646                                 entry->ifindex = msg->ifi_index;
 647                                 entry->flags = 0;
 648                                 entry->usable = hydra->kernel_interface->is_interface_usable(
 649                                                                                                 hydra->kernel_interface, name);
 650                                 entry->addrs = linked_list_create();
 651                                 this->ifaces->insert_last(this->ifaces, entry);
 652                         }
 653                         strncpy(entry->ifname, name, IFNAMSIZ);
 654                         entry->ifname[IFNAMSIZ-1] = '\0';
 655                         if (event && entry->usable)
 656                         {
 657                                 if (!(entry->flags & IFF_UP) && (msg->ifi_flags & IFF_UP))
 658                                 {
 659                                         update = update_routes = TRUE;
 660                                         DBG1(DBG_KNL, "interface %s activated", name);
 661                                 }
 662                                 if ((entry->flags & IFF_UP) && !(msg->ifi_flags & IFF_UP))
 663                                 {
 664                                         update = TRUE;
 665                                         DBG1(DBG_KNL, "interface %s deactivated", name);
 666                                 }
 667                         }
 668                         entry->flags = msg->ifi_flags;
 669                         break;
 670                 }
 671                 case RTM_DELLINK:
 672                 {
 673                         enumerator = this->ifaces->create_enumerator(this->ifaces);
 674                         while (enumerator->enumerate(enumerator, &current))
 675                         {
 676                                 if (current->ifindex == msg->ifi_index)
 677                                 {
 678                                         if (event && current->usable)
 679                                         {
 680                                                 update = TRUE;
 681                                                 DBG1(DBG_KNL, "interface %s deleted", current->ifname);
 682                                         }
 683                                         this->ifaces->remove_at(this->ifaces, enumerator);
 684                                         iface_entry_destroy(current);
 685                                         break;
 686                                 }
 687                         }
 688                         enumerator->destroy(enumerator);
 689                         break;
 690                 }
 691         }
 692         this->mutex->unlock(this->mutex);
 693
 694         if (update_routes && event)
 695         {
 696                 queue_route_reinstall(this, strdup(name));
 697         }
 698
 699         /* send an update to all IKE_SAs */
 700         if (update && event)
 701         {
 702                 fire_roam_event(this, TRUE);
 703         }
 704 }
 705
 706 /**
 707  * process RTM_NEWADDR/RTM_DELADDR from kernel
 708  */
 709 static void process_addr(private_kernel_netlink_net_t *this,
 710                                                  struct nlmsghdr *hdr, bool event)
 711 {
 712         struct ifaddrmsg* msg = (struct ifaddrmsg*)(NLMSG_DATA(hdr));
 713         struct rtattr *rta = IFA_RTA(msg);
 714         size_t rtasize = IFA_PAYLOAD (hdr);
 715         host_t *host = NULL;
 716         enumerator_t *ifaces, *addrs;
 717         iface_entry_t *iface;
 718         addr_entry_t *addr;
 719         chunk_t local = chunk_empty, address = chunk_empty;
 720         char *route_ifname = NULL;
 721         bool update = FALSE, found = FALSE, changed = FALSE;
 722
 723         while (RTA_OK(rta, rtasize))
 724         {
 725                 switch (rta->rta_type)
 726                 {
 727                         case IFA_LOCAL:
 728                                 local.ptr = RTA_DATA(rta);
 729                                 local.len = RTA_PAYLOAD(rta);
 730                                 break;
 731                         case IFA_ADDRESS:
 732                                 address.ptr = RTA_DATA(rta);
 733                                 address.len = RTA_PAYLOAD(rta);
 734                                 break;
 735                 }
 736                 rta = RTA_NEXT(rta, rtasize);
 737         }
 738
 739         /* For PPP interfaces, we need the IFA_LOCAL address,
 740          * IFA_ADDRESS is the peers address. But IFA_LOCAL is
 741          * not included in all cases (IPv6?), so fallback to IFA_ADDRESS. */
 742         if (local.ptr)
 743         {
 744                 host = host_create_from_chunk(msg->ifa_family, local, 0);
 745         }
 746         else if (address.ptr)
 747         {
 748                 host = host_create_from_chunk(msg->ifa_family, address, 0);
 749         }
 750
 751         if (host == NULL)
 752         {       /* bad family? */
 753                 return;
 754         }
 755
 756         this->mutex->lock(this->mutex);
 757         ifaces = this->ifaces->create_enumerator(this->ifaces);
 758         while (ifaces->enumerate(ifaces, &iface))
 759         {
 760                 if (iface->ifindex == msg->ifa_index)
 761                 {
 762                         addrs = iface->addrs->create_enumerator(iface->addrs);
 763                         while (addrs->enumerate(addrs, &addr))
 764                         {
 765                                 if (host->ip_equals(host, addr->ip))
 766                                 {
 767                                         found = TRUE;
 768                                         if (hdr->nlmsg_type == RTM_DELADDR)
 769                                         {
 770                                                 iface->addrs->remove_at(iface->addrs, addrs);
 771                                                 if (!addr->virtual && iface->usable)
 772                                                 {
 773                                                         changed = TRUE;
 774                                                         DBG1(DBG_KNL, "%H disappeared from %s",
 775                                                                  host, iface->ifname);
 776                                                 }
 777                                                 addr_entry_destroy(addr);
 778                                         }
 779                                         else if (hdr->nlmsg_type == RTM_NEWADDR && addr->virtual)
 780                                         {
 781                                                 addr->refcount = 1;
 782                                         }
 783                                 }
 784                         }
 785                         addrs->destroy(addrs);
 786
 787                         if (hdr->nlmsg_type == RTM_NEWADDR)
 788                         {
 789                                 if (!found)
 790                                 {
 791                                         found = TRUE;
 792                                         changed = TRUE;
 793                                         route_ifname = strdup(iface->ifname);
 794                                         addr = malloc_thing(addr_entry_t);
 795                                         addr->ip = host->clone(host);
 796                                         addr->virtual = FALSE;
 797                                         addr->refcount = 1;
 798                                         addr->scope = msg->ifa_scope;
 799
 800                                         iface->addrs->insert_last(iface->addrs, addr);
 801                                         if (event && iface->usable)
 802                                         {
 803                                                 DBG1(DBG_KNL, "%H appeared on %s", host, iface->ifname);
 804                                         }
 805                                 }
 806                         }
 807                         if (found && (iface->flags & IFF_UP))
 808                         {
 809                                 update = TRUE;
 810                         }
 811                         if (!iface->usable)
 812                         {       /* ignore events for interfaces excluded by config */
 813                                 update = changed = FALSE;
 814                         }
 815                         break;
 816                 }
 817         }
 818         ifaces->destroy(ifaces);
 819         this->mutex->unlock(this->mutex);
 820
 821         if (update && event && route_ifname)
 822         {
 823                 queue_route_reinstall(this, route_ifname);
 824         }
 825         else
 826         {
 827                 free(route_ifname);
 828         }
 829         host->destroy(host);
 830
 831         /* send an update to all IKE_SAs */
 832         if (update && event && changed)
 833         {
 834                 fire_roam_event(this, TRUE);
 835         }
 836 }
 837
 838 /**
 839  * process RTM_NEWROUTE and RTM_DELROUTE from kernel
 840  */
 841 static void process_route(private_kernel_netlink_net_t *this, struct nlmsghdr *hdr)
 842 {
 843         struct rtmsg* msg = (struct rtmsg*)(NLMSG_DATA(hdr));
 844         struct rtattr *rta = RTM_RTA(msg);
 845         size_t rtasize = RTM_PAYLOAD(hdr);
 846         u_int32_t rta_oif = 0;
 847         host_t *host = NULL;
 848
 849         /* ignore routes added by us or in the local routing table (local addrs) */
 850         if (msg->rtm_table && (msg->rtm_table == this->routing_table ||
 851                                                    msg->rtm_table == RT_TABLE_LOCAL))
 852         {
 853                 return;
 854         }
 855         else if (msg->rtm_flags & RTM_F_CLONED)
 856         {       /* ignore cached routes, seem to be created a lot for IPv6 */
 857                 return;
 858         }
 859
 860         while (RTA_OK(rta, rtasize))
 861         {
 862                 switch (rta->rta_type)
 863                 {
 864                         case RTA_PREFSRC:
 865                                 DESTROY_IF(host);
 866                                 host = host_create_from_chunk(msg->rtm_family,
 867                                                         chunk_create(RTA_DATA(rta), RTA_PAYLOAD(rta)), 0);
 868                                 break;
 869                         case RTA_OIF:
 870                                 if (RTA_PAYLOAD(rta) == sizeof(rta_oif))
 871                                 {
 872                                         rta_oif = *(u_int32_t*)RTA_DATA(rta);
 873                                 }
 874                                 break;
 875                 }
 876                 rta = RTA_NEXT(rta, rtasize);
 877         }
 878         this->mutex->lock(this->mutex);
 879         if (rta_oif && !is_interface_up_and_usable(this, rta_oif))
 880         {       /* ignore route changes for interfaces that are ignored or down */
 881                 this->mutex->unlock(this->mutex);
 882                 DESTROY_IF(host);
 883                 return;
 884         }
 885         if (!host && rta_oif)
 886         {
 887                 host = get_interface_address(this, rta_oif, msg->rtm_family, NULL);
 888         }
 889         if (host)
 890         {
 891                 if (!get_vip_refcount(this, host))
 892                 {       /* ignore routes added for virtual IPs */
 893                         fire_roam_event(this, FALSE);
 894                 }
 895                 host->destroy(host);
 896         }
 897         this->mutex->unlock(this->mutex);
 898 }
 899
 900 /**
 901  * Receives events from kernel
 902  */
 903 static job_requeue_t receive_events(private_kernel_netlink_net_t *this)
 904 {
 905         char response[1024];
 906         struct nlmsghdr *hdr = (struct nlmsghdr*)response;
 907         struct sockaddr_nl addr;
 908         socklen_t addr_len = sizeof(addr);
 909         int len;
 910         bool oldstate;
 911
 912         oldstate = thread_cancelability(TRUE);
 913         len = recvfrom(this->socket_events, response, sizeof(response), 0,
 914                                    (struct sockaddr*)&addr, &addr_len);
 915         thread_cancelability(oldstate);
 916
 917         if (len < 0)
 918         {
 919                 switch (errno)
 920                 {
 921                         case EINTR:
 922                                 /* interrupted, try again */
 923                                 return JOB_REQUEUE_DIRECT;
 924                         case EAGAIN:
 925                                 /* no data ready, select again */
 926                                 return JOB_REQUEUE_DIRECT;
 927                         default:
 928                                 DBG1(DBG_KNL, "unable to receive from rt event socket");
 929                                 sleep(1);
 930                                 return JOB_REQUEUE_FAIR;
 931                 }
 932         }
 933
 934         if (addr.nl_pid != 0)
 935         {       /* not from kernel. not interested, try another one */
 936                 return JOB_REQUEUE_DIRECT;
 937         }
 938
 939         while (NLMSG_OK(hdr, len))
 940         {
 941                 /* looks good so far, dispatch netlink message */
 942                 switch (hdr->nlmsg_type)
 943                 {
 944                         case RTM_NEWADDR:
 945                         case RTM_DELADDR:
 946                                 process_addr(this, hdr, TRUE);
 947                                 this->condvar->broadcast(this->condvar);
 948                                 break;
 949                         case RTM_NEWLINK:
 950                         case RTM_DELLINK:
 951                                 process_link(this, hdr, TRUE);
 952                                 this->condvar->broadcast(this->condvar);
 953                                 break;
 954                         case RTM_NEWROUTE:
 955                         case RTM_DELROUTE:
 956                                 if (this->process_route)
 957                                 {
 958                                         process_route(this, hdr);
 959                                 }
 960                                 break;
 961                         default:
 962                                 break;
 963                 }
 964                 hdr = NLMSG_NEXT(hdr, len);
 965         }
 966         return JOB_REQUEUE_DIRECT;
 967 }
 968
 969 /** enumerator over addresses */
 970 typedef struct {
 971         private_kernel_netlink_net_t* this;
 972         /** whether to enumerate down interfaces */
 973         bool include_down_ifaces;
 974         /** whether to enumerate virtual ip addresses */
 975         bool include_virtual_ips;
 976         /** whether to enumerate loopback interfaces */
 977         bool include_loopback;
 978 } address_enumerator_t;
 979
 980 /**
 981  * cleanup function for address enumerator
 982  */
 983 static void address_enumerator_destroy(address_enumerator_t *data)
 984 {
 985         data->this->mutex->unlock(data->this->mutex);
 986         free(data);
 987 }
 988
 989 /**
 990  * filter for addresses
 991  */
 992 static bool filter_addresses(address_enumerator_t *data,
 993                                                          addr_entry_t** in, host_t** out)
 994 {
 995         if (!data->include_virtual_ips && (*in)->virtual)
 996         {       /* skip virtual interfaces added by us */
 997                 return FALSE;
 998         }
 999         if ((*in)->scope >= RT_SCOPE_LINK)
1000         {       /* skip addresses with a unusable scope */
1001                 return FALSE;
1002         }
1003         *out = (*in)->ip;
1004         return TRUE;
1005 }
1006
1007 /**
1008  * enumerator constructor for interfaces
1009  */
1010 static enumerator_t *create_iface_enumerator(iface_entry_t *iface,
1011                                                                                          address_enumerator_t *data)
1012 {
1013         return enumerator_create_filter(
1014                                 iface->addrs->create_enumerator(iface->addrs),
1015                                 (void*)filter_addresses, data, NULL);
1016 }
1017
1018 /**
1019  * filter for interfaces
1020  */
1021 static bool filter_interfaces(address_enumerator_t *data, iface_entry_t** in,
1022                                                           iface_entry_t** out)
1023 {
1024         if (!(*in)->usable)
1025         {       /* skip interfaces excluded by config */
1026                 return FALSE;
1027         }
1028         if (!data->include_loopback && ((*in)->flags & IFF_LOOPBACK))
1029         {       /* ignore loopback devices */
1030                 return FALSE;
1031         }
1032         if (!data->include_down_ifaces && !((*in)->flags & IFF_UP))
1033         {       /* skip interfaces not up */
1034                 return FALSE;
1035         }
1036         *out = *in;
1037         return TRUE;
1038 }
1039
1040 METHOD(kernel_net_t, create_address_enumerator, enumerator_t*,
1041         private_kernel_netlink_net_t *this,
1042         bool include_down_ifaces, bool include_virtual_ips, bool include_loopback)
1043 {
1044         address_enumerator_t *data = malloc_thing(address_enumerator_t);
1045         data->this = this;
1046         data->include_down_ifaces = include_down_ifaces;
1047         data->include_virtual_ips = include_virtual_ips;
1048         data->include_loopback = include_loopback;
1049
1050         this->mutex->lock(this->mutex);
1051         return enumerator_create_nested(
1052                                 enumerator_create_filter(
1053                                         this->ifaces->create_enumerator(this->ifaces),
1054                                         (void*)filter_interfaces, data, NULL),
1055                                 (void*)create_iface_enumerator, data,
1056                                 (void*)address_enumerator_destroy);
1057 }
1058
1059 METHOD(kernel_net_t, get_interface_name, bool,
1060         private_kernel_netlink_net_t *this, host_t* ip, char **name)
1061 {
1062         enumerator_t *ifaces, *addrs;
1063         iface_entry_t *iface;
1064         addr_entry_t *addr;
1065         bool found = FALSE, ignored = FALSE;
1066
1067         if (ip->is_anyaddr(ip))
1068         {
1069                 return FALSE;
1070         }
1071
1072         this->mutex->lock(this->mutex);
1073         ifaces = this->ifaces->create_enumerator(this->ifaces);
1074         while (ifaces->enumerate(ifaces, &iface))
1075         {
1076                 addrs = iface->addrs->create_enumerator(iface->addrs);
1077                 while (addrs->enumerate(addrs, &addr))
1078                 {
1079                         if (ip->ip_equals(ip, addr->ip))
1080                         {
1081                                 found = TRUE;
1082                                 if (!iface->usable)
1083                                 {
1084                                         ignored = TRUE;
1085                                         break;
1086                                 }
1087                                 if (name)
1088                                 {
1089                                         *name = strdup(iface->ifname);
1090                                 }
1091                                 break;
1092                         }
1093                 }
1094                 addrs->destroy(addrs);
1095                 if (found)
1096                 {
1097                         break;
1098                 }
1099         }
1100         ifaces->destroy(ifaces);
1101         this->mutex->unlock(this->mutex);
1102
1103         if (!ignored)
1104         {
1105                 if (!found)
1106                 {
1107                         DBG2(DBG_KNL, "%H is not a local address", ip);
1108                 }
1109                 else if (name)
1110                 {
1111                         DBG2(DBG_KNL, "%H is on interface %s", ip, *name);
1112                 }
1113         }
1114         return found && !ignored;
1115 }
1116
1117 /**
1118  * get the index of an interface by name
1119  */
1120 static int get_interface_index(private_kernel_netlink_net_t *this, char* name)
1121 {
1122         enumerator_t *ifaces;
1123         iface_entry_t *iface;
1124         int ifindex = 0;
1125
1126         DBG2(DBG_KNL, "getting iface index for %s", name);
1127
1128         this->mutex->lock(this->mutex);
1129         ifaces = this->ifaces->create_enumerator(this->ifaces);
1130         while (ifaces->enumerate(ifaces, &iface))
1131         {
1132                 if (streq(name, iface->ifname))
1133                 {
1134                         ifindex = iface->ifindex;
1135                         break;
1136                 }
1137         }
1138         ifaces->destroy(ifaces);
1139         this->mutex->unlock(this->mutex);
1140
1141         if (ifindex == 0)
1142         {
1143                 DBG1(DBG_KNL, "unable to get interface index for %s", name);
1144         }
1145         return ifindex;
1146 }
1147
1148 /**
1149  * check if an address (chunk) addr is in subnet (net with net_len net bits)
1150  */
1151 static bool addr_in_subnet(chunk_t addr, chunk_t net, int net_len)
1152 {
1153         static const u_char mask[] = { 0x00, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe };
1154         int byte = 0;
1155
1156         if (net_len == 0)
1157         {       /* any address matches a /0 network */
1158                 return TRUE;
1159         }
1160         if (addr.len != net.len || net_len > 8 * net.len )
1161         {
1162                 return FALSE;
1163         }
1164         /* scan through all bytes in network order */
1165         while (net_len > 0)
1166         {
1167                 if (net_len < 8)
1168                 {
1169                         return (mask[net_len] & addr.ptr[byte]) == (mask[net_len] & net.ptr[byte]);
1170                 }
1171                 else
1172                 {
1173                         if (addr.ptr[byte] != net.ptr[byte])
1174                         {
1175                                 return FALSE;
1176                         }
1177                         byte++;
1178                         net_len -= 8;
1179                 }
1180         }
1181         return TRUE;
1182 }
1183
1184 /**
1185  * Store information about a route retrieved via RTNETLINK
1186  */
1187 typedef struct {
1188         chunk_t gtw;
1189         chunk_t src;
1190         chunk_t dst;
1191         host_t *src_host;
1192         u_int8_t dst_len;
1193         u_int32_t table;
1194         u_int32_t oif;
1195 } rt_entry_t;
1196
1197 /**
1198  * Free a route entry
1199  */
1200 static void rt_entry_destroy(rt_entry_t *this)
1201 {
1202         DESTROY_IF(this->src_host);
1203         free(this);
1204 }
1205
1206 /**
1207  * Parse route received with RTM_NEWROUTE. The given rt_entry_t object will be
1208  * reused if not NULL.
1209  *
1210  * Returned chunks point to internal data of the Netlink message.
1211  */
1212 static rt_entry_t *parse_route(struct nlmsghdr *hdr, rt_entry_t *route)
1213 {
1214         struct rtattr *rta;
1215         struct rtmsg *msg;
1216         size_t rtasize;
1217
1218         msg = (struct rtmsg*)(NLMSG_DATA(hdr));
1219         rta = RTM_RTA(msg);
1220         rtasize = RTM_PAYLOAD(hdr);
1221
1222         if (route)
1223         {
1224                 route->gtw = chunk_empty;
1225                 route->src = chunk_empty;
1226                 route->dst = chunk_empty;
1227                 route->dst_len = msg->rtm_dst_len;
1228                 route->table = msg->rtm_table;
1229                 route->oif = 0;
1230         }
1231         else
1232         {
1233                 INIT(route,
1234                         .dst_len = msg->rtm_dst_len,
1235                         .table = msg->rtm_table,
1236                 );
1237         }
1238
1239         while (RTA_OK(rta, rtasize))
1240         {
1241                 switch (rta->rta_type)
1242                 {
1243                         case RTA_PREFSRC:
1244                                 route->src = chunk_create(RTA_DATA(rta), RTA_PAYLOAD(rta));
1245                                 break;
1246                         case RTA_GATEWAY:
1247                                 route->gtw = chunk_create(RTA_DATA(rta), RTA_PAYLOAD(rta));
1248                                 break;
1249                         case RTA_DST:
1250                                 route->dst = chunk_create(RTA_DATA(rta), RTA_PAYLOAD(rta));
1251                                 break;
1252                         case RTA_OIF:
1253                                 if (RTA_PAYLOAD(rta) == sizeof(route->oif))
1254                                 {
1255                                         route->oif = *(u_int32_t*)RTA_DATA(rta);
1256                                 }
1257                                 break;
1258 #ifdef HAVE_RTA_TABLE
1259                         case RTA_TABLE:
1260                                 if (RTA_PAYLOAD(rta) == sizeof(route->table))
1261                                 {
1262                                         route->table = *(u_int32_t*)RTA_DATA(rta);
1263                                 }
1264                                 break;
1265 #endif /* HAVE_RTA_TABLE*/
1266                 }
1267                 rta = RTA_NEXT(rta, rtasize);
1268         }
1269         return route;
1270 }
1271
1272 /**
1273  * Get a route: If "nexthop", the nexthop is returned. source addr otherwise.
1274  */
1275 static host_t *get_route(private_kernel_netlink_net_t *this, host_t *dest,
1276                                                  bool nexthop, host_t *candidate)
1277 {
1278         netlink_buf_t request;
1279         struct nlmsghdr *hdr, *out, *current;
1280         struct rtmsg *msg;
1281         chunk_t chunk;
1282         size_t len;
1283         linked_list_t *routes;
1284         rt_entry_t *route = NULL, *best = NULL;
1285         enumerator_t *enumerator;
1286         host_t *addr = NULL;
1287
1288         memset(&request, 0, sizeof(request));
1289
1290         hdr = (struct nlmsghdr*)request;
1291         hdr->nlmsg_flags = NLM_F_REQUEST;
1292         if (dest->get_family(dest) == AF_INET || this->rta_prefsrc_for_ipv6 ||
1293                 this->routing_table)
1294         {       /* kernels prior to 3.0 do not support RTA_PREFSRC for IPv6 routes.
1295                  * as we want to ignore routes with virtual IPs we cannot use DUMP
1296                  * if these routes are not installed in a separate table */
1297                 hdr->nlmsg_flags |= NLM_F_DUMP;
1298         }
1299         hdr->nlmsg_type = RTM_GETROUTE;
1300         hdr->nlmsg_len = NLMSG_LENGTH(sizeof(struct rtmsg));
1301
1302         msg = (struct rtmsg*)NLMSG_DATA(hdr);
1303         msg->rtm_family = dest->get_family(dest);
1304         if (candidate)
1305         {
1306                 chunk = candidate->get_address(candidate);
1307                 netlink_add_attribute(hdr, RTA_PREFSRC, chunk, sizeof(request));
1308         }
1309         chunk = dest->get_address(dest);
1310         netlink_add_attribute(hdr, RTA_DST, chunk, sizeof(request));
1311
1312         if (this->socket->send(this->socket, hdr, &out, &len) != SUCCESS)
1313         {
1314                 DBG2(DBG_KNL, "getting %s to reach %H failed",
1315                          nexthop ? "nexthop" : "address", dest);
1316                 return NULL;
1317         }
1318         routes = linked_list_create();
1319         this->mutex->lock(this->mutex);
1320
1321         for (current = out; NLMSG_OK(current, len);
1322                  current = NLMSG_NEXT(current, len))
1323         {
1324                 switch (current->nlmsg_type)
1325                 {
1326                         case NLMSG_DONE:
1327                                 break;
1328                         case RTM_NEWROUTE:
1329                         {
1330                                 rt_entry_t *other;
1331                                 uintptr_t table;
1332
1333                                 route = parse_route(current, route);
1334
1335                                 table = (uintptr_t)route->table;
1336                                 if (this->rt_exclude->find_first(this->rt_exclude, NULL,
1337                                                                                                  (void**)&table) == SUCCESS)
1338                                 {       /* route is from an excluded routing table */
1339                                         continue;
1340                                 }
1341                                 if (this->routing_table != 0 &&
1342                                         route->table == this->routing_table)
1343                                 {       /* route is from our own ipsec routing table */
1344                                         continue;
1345                                 }
1346                                 if (route->oif && !is_interface_up_and_usable(this, route->oif))
1347                                 {       /* interface is down */
1348                                         continue;
1349                                 }
1350                                 if (!addr_in_subnet(chunk, route->dst, route->dst_len))
1351                                 {       /* route destination does not contain dest */
1352                                         continue;
1353                                 }
1354                                 if (route->src.ptr)
1355                                 {       /* verify source address, if any */
1356                                         host_t *src = host_create_from_chunk(msg->rtm_family,
1357                                                                                                                  route->src, 0);
1358                                         if (src && get_vip_refcount(this, src))
1359                                         {       /* ignore routes installed by us */
1360                                                 src->destroy(src);
1361                                                 continue;
1362                                         }
1363                                         route->src_host = src;
1364                                 }
1365                                 /* insert route, sorted by decreasing network prefix */
1366                                 enumerator = routes->create_enumerator(routes);
1367                                 while (enumerator->enumerate(enumerator, &other))
1368                                 {
1369                                         if (route->dst_len > other->dst_len)
1370                                         {
1371                                                 break;
1372                                         }
1373                                 }
1374                                 routes->insert_before(routes, enumerator, route);
1375                                 enumerator->destroy(enumerator);
1376                                 route = NULL;
1377                                 continue;
1378                         }
1379                         default:
1380                                 continue;
1381                 }
1382                 break;
1383         }
1384         if (route)
1385         {
1386                 rt_entry_destroy(route);
1387         }
1388
1389         /* now we have a list of routes matching dest, sorted by net prefix.
1390          * we will look for source addresses for these routes and select the one
1391          * with the preferred source address, if possible */
1392         enumerator = routes->create_enumerator(routes);
1393         while (enumerator->enumerate(enumerator, &route))
1394         {
1395                 if (route->src_host)
1396                 {       /* got a source address with the route, if no preferred source
1397                          * is given or it matches we are done, as this is the best route */
1398                         if (!candidate || candidate->ip_equals(candidate, route->src_host))
1399                         {
1400                                 best = route;
1401                                 break;
1402                         }
1403                         else if (route->oif)
1404                         {       /* no match yet, maybe it is assigned to the same interface */
1405                                 host_t *src = get_interface_address(this, route->oif,
1406                                                                                                         msg->rtm_family, candidate);
1407                                 if (src && src->ip_equals(src, candidate))
1408                                 {
1409                                         route->src_host->destroy(route->src_host);
1410                                         route->src_host = src;
1411                                         best = route;
1412                                         break;
1413                                 }
1414                                 DESTROY_IF(src);
1415                         }
1416                         /* no luck yet with the source address. if this is the best (first)
1417                          * route we store it as fallback in case we don't find a route with
1418                          * the preferred source */
1419                         best = best ?: route;
1420                         continue;
1421                 }
1422                 if (route->oif)
1423                 {       /* no src, but an interface - get address from it */
1424                         route->src_host = get_interface_address(this, route->oif,
1425                                                                                                         msg->rtm_family, candidate);
1426                         if (route->src_host)
1427                         {       /* we handle this address the same as the one above */
1428                                 if (!candidate ||
1429                                          candidate->ip_equals(candidate, route->src_host))
1430                                 {
1431                                         best = route;
1432                                         break;
1433                                 }
1434                                 best = best ?: route;
1435                                 continue;
1436                         }
1437                 }
1438                 if (route->gtw.ptr)
1439                 {       /* no src, no iface, but a gateway - lookup src to reach gtw */
1440                         host_t *gtw;
1441
1442                         gtw = host_create_from_chunk(msg->rtm_family, route->gtw, 0);
1443                         route->src_host = get_route(this, gtw, FALSE, candidate);
1444                         gtw->destroy(gtw);
1445                         if (route->src_host)
1446                         {       /* more of the same */
1447                                 if (!candidate ||
1448                                          candidate->ip_equals(candidate, route->src_host))
1449                                 {
1450                                         best = route;
1451                                         break;
1452                                 }
1453                                 best = best ?: route;
1454                         }
1455                 }
1456         }
1457         enumerator->destroy(enumerator);
1458
1459         if (nexthop)
1460         {       /* nexthop lookup, return gateway if any */
1461                 if (best || routes->get_first(routes, (void**)&best) == SUCCESS)
1462                 {
1463                         addr = host_create_from_chunk(msg->rtm_family, best->gtw, 0);
1464                 }
1465                 addr = addr ?: dest->clone(dest);
1466         }
1467         else
1468         {
1469                 if (best)
1470                 {
1471                         addr = best->src_host->clone(best->src_host);
1472                 }
1473         }
1474         this->mutex->unlock(this->mutex);
1475         routes->destroy_function(routes, (void*)rt_entry_destroy);
1476         free(out);
1477
1478         if (addr)
1479         {
1480                 DBG2(DBG_KNL, "using %H as %s to reach %H", addr,
1481                          nexthop ? "nexthop" : "address", dest);
1482         }
1483         else
1484         {
1485                 DBG2(DBG_KNL, "no %s found to reach %H",
1486                          nexthop ? "nexthop" : "address", dest);
1487         }
1488         return addr;
1489 }
1490
1491 METHOD(kernel_net_t, get_source_addr, host_t*,
1492         private_kernel_netlink_net_t *this, host_t *dest, host_t *src)
1493 {
1494         return get_route(this, dest, FALSE, src);
1495 }
1496
1497 METHOD(kernel_net_t, get_nexthop, host_t*,
1498         private_kernel_netlink_net_t *this, host_t *dest, host_t *src)
1499 {
1500         return get_route(this, dest, TRUE, src);
1501 }
1502
1503 /**
1504  * Manages the creation and deletion of ip addresses on an interface.
1505  * By setting the appropriate nlmsg_type, the ip will be set or unset.
1506  */
1507 static status_t manage_ipaddr(private_kernel_netlink_net_t *this, int nlmsg_type,
1508                                                           int flags, int if_index, host_t *ip)
1509 {
1510         netlink_buf_t request;
1511         struct nlmsghdr *hdr;
1512         struct ifaddrmsg *msg;
1513         chunk_t chunk;
1514
1515         memset(&request, 0, sizeof(request));
1516
1517         chunk = ip->get_address(ip);
1518
1519         hdr = (struct nlmsghdr*)request;
1520         hdr->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK | flags;
1521         hdr->nlmsg_type = nlmsg_type;
1522         hdr->nlmsg_len = NLMSG_LENGTH(sizeof(struct ifaddrmsg));
1523
1524         msg = (struct ifaddrmsg*)NLMSG_DATA(hdr);
1525         msg->ifa_family = ip->get_family(ip);
1526         msg->ifa_flags = 0;
1527         msg->ifa_prefixlen = 8 * chunk.len;
1528         msg->ifa_scope = RT_SCOPE_UNIVERSE;
1529         msg->ifa_index = if_index;
1530
1531         netlink_add_attribute(hdr, IFA_LOCAL, chunk, sizeof(request));
1532
1533         return this->socket->send_ack(this->socket, hdr);
1534 }
1535
1536 METHOD(kernel_net_t, add_ip, status_t,
1537         private_kernel_netlink_net_t *this, host_t *virtual_ip, host_t *iface_ip)
1538 {
1539         iface_entry_t *iface;
1540         addr_entry_t *addr;
1541         enumerator_t *addrs, *ifaces;
1542         int ifindex;
1543
1544         if (!this->install_virtual_ip)
1545         {       /* disabled by config */
1546                 return SUCCESS;
1547         }
1548
1549         DBG2(DBG_KNL, "adding virtual IP %H", virtual_ip);
1550
1551         this->mutex->lock(this->mutex);
1552         ifaces = this->ifaces->create_enumerator(this->ifaces);
1553         while (ifaces->enumerate(ifaces, &iface))
1554         {
1555                 bool iface_found = FALSE;
1556
1557                 addrs = iface->addrs->create_enumerator(iface->addrs);
1558                 while (addrs->enumerate(addrs, &addr))
1559                 {
1560                         if (iface_ip->ip_equals(iface_ip, addr->ip))
1561                         {
1562                                 iface_found = TRUE;
1563                         }
1564                         else if (virtual_ip->ip_equals(virtual_ip, addr->ip))
1565                         {
1566                                 addr->refcount++;
1567                                 DBG2(DBG_KNL, "virtual IP %H already installed on %s",
1568                                          virtual_ip, iface->ifname);
1569                                 addrs->destroy(addrs);
1570                                 ifaces->destroy(ifaces);
1571                                 this->mutex->unlock(this->mutex);
1572                                 return SUCCESS;
1573                         }
1574                 }
1575                 addrs->destroy(addrs);
1576
1577                 if (iface_found)
1578                 {
1579                         ifindex = iface->ifindex;
1580                         addr = malloc_thing(addr_entry_t);
1581                         addr->ip = virtual_ip->clone(virtual_ip);
1582                         addr->refcount = 0;
1583                         addr->virtual = TRUE;
1584                         addr->scope = RT_SCOPE_UNIVERSE;
1585                         iface->addrs->insert_last(iface->addrs, addr);
1586
1587                         if (manage_ipaddr(this, RTM_NEWADDR, NLM_F_CREATE | NLM_F_EXCL,
1588                                                           ifindex, virtual_ip) == SUCCESS)
1589                         {
1590                                 while (get_vip_refcount(this, virtual_ip) == 0)
1591                                 {       /* wait until address appears */
1592                                         this->condvar->wait(this->condvar, this->mutex);
1593                                 }
1594                                 ifaces->destroy(ifaces);
1595                                 this->mutex->unlock(this->mutex);
1596                                 return SUCCESS;
1597                         }
1598                         ifaces->destroy(ifaces);
1599                         this->mutex->unlock(this->mutex);
1600                         DBG1(DBG_KNL, "adding virtual IP %H failed", virtual_ip);
1601                         return FAILED;
1602                 }
1603         }
1604         ifaces->destroy(ifaces);
1605         this->mutex->unlock(this->mutex);
1606
1607         DBG1(DBG_KNL, "interface address %H not found, unable to install"
1608                  "virtual IP %H", iface_ip, virtual_ip);
1609         return FAILED;
1610 }
1611
1612 METHOD(kernel_net_t, del_ip, status_t,
1613         private_kernel_netlink_net_t *this, host_t *virtual_ip)
1614 {
1615         iface_entry_t *iface;
1616         addr_entry_t *addr;
1617         enumerator_t *addrs, *ifaces;
1618         status_t status;
1619         int ifindex;
1620
1621         if (!this->install_virtual_ip)
1622         {       /* disabled by config */
1623                 return SUCCESS;
1624         }
1625
1626         DBG2(DBG_KNL, "deleting virtual IP %H", virtual_ip);
1627
1628         this->mutex->lock(this->mutex);
1629         ifaces = this->ifaces->create_enumerator(this->ifaces);
1630         while (ifaces->enumerate(ifaces, &iface))
1631         {
1632                 addrs = iface->addrs->create_enumerator(iface->addrs);
1633                 while (addrs->enumerate(addrs, &addr))
1634                 {
1635                         if (virtual_ip->ip_equals(virtual_ip, addr->ip))
1636                         {
1637                                 ifindex = iface->ifindex;
1638                                 if (addr->refcount == 1)
1639                                 {
1640                                         status = manage_ipaddr(this, RTM_DELADDR, 0,
1641                                                                                    ifindex, virtual_ip);
1642                                         if (status == SUCCESS)
1643                                         {       /* wait until the address is really gone */
1644                                                 while (get_vip_refcount(this, virtual_ip) > 0)
1645                                                 {
1646                                                         this->condvar->wait(this->condvar, this->mutex);
1647                                                 }
1648                                         }
1649                                         addrs->destroy(addrs);
1650                                         ifaces->destroy(ifaces);
1651                                         this->mutex->unlock(this->mutex);
1652                                         return status;
1653                                 }
1654                                 else
1655                                 {
1656                                         addr->refcount--;
1657                                 }
1658                                 DBG2(DBG_KNL, "virtual IP %H used by other SAs, not deleting",
1659                                          virtual_ip);
1660                                 addrs->destroy(addrs);
1661                                 ifaces->destroy(ifaces);
1662                                 this->mutex->unlock(this->mutex);
1663                                 return SUCCESS;
1664                         }
1665                 }
1666                 addrs->destroy(addrs);
1667         }
1668         ifaces->destroy(ifaces);
1669         this->mutex->unlock(this->mutex);
1670
1671         DBG2(DBG_KNL, "virtual IP %H not cached, unable to delete", virtual_ip);
1672         return FAILED;
1673 }
1674
1675 /**
1676  * Manages source routes in the routing table.
1677  * By setting the appropriate nlmsg_type, the route gets added or removed.
1678  */
1679 static status_t manage_srcroute(private_kernel_netlink_net_t *this,
1680                                                                 int nlmsg_type, int flags, chunk_t dst_net,
1681                                                                 u_int8_t prefixlen, host_t *gateway,
1682                                                                 host_t *src_ip, char *if_name)
1683 {
1684         netlink_buf_t request;
1685         struct nlmsghdr *hdr;
1686         struct rtmsg *msg;
1687         int ifindex;
1688         chunk_t chunk;
1689
1690         /* if route is 0.0.0.0/0, we can't install it, as it would
1691          * overwrite the default route. Instead, we add two routes:
1692          * 0.0.0.0/1 and 128.0.0.0/1 */
1693         if (this->routing_table == 0 && prefixlen == 0)
1694         {
1695                 chunk_t half_net;
1696                 u_int8_t half_prefixlen;
1697                 status_t status;
1698
1699                 half_net = chunk_alloca(dst_net.len);
1700                 memset(half_net.ptr, 0, half_net.len);
1701                 half_prefixlen = 1;
1702
1703                 status = manage_srcroute(this, nlmsg_type, flags, half_net, half_prefixlen,
1704                                         gateway, src_ip, if_name);
1705                 half_net.ptr[0] |= 0x80;
1706                 status = manage_srcroute(this, nlmsg_type, flags, half_net, half_prefixlen,
1707                                         gateway, src_ip, if_name);
1708                 return status;
1709         }
1710
1711         memset(&request, 0, sizeof(request));
1712
1713         hdr = (struct nlmsghdr*)request;
1714         hdr->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK | flags;
1715         hdr->nlmsg_type = nlmsg_type;
1716         hdr->nlmsg_len = NLMSG_LENGTH(sizeof(struct rtmsg));
1717
1718         msg = (struct rtmsg*)NLMSG_DATA(hdr);
1719         msg->rtm_family = src_ip->get_family(src_ip);
1720         msg->rtm_dst_len = prefixlen;
1721         msg->rtm_table = this->routing_table;
1722         msg->rtm_protocol = RTPROT_STATIC;
1723         msg->rtm_type = RTN_UNICAST;
1724         msg->rtm_scope = RT_SCOPE_UNIVERSE;
1725
1726         netlink_add_attribute(hdr, RTA_DST, dst_net, sizeof(request));
1727         chunk = src_ip->get_address(src_ip);
1728         netlink_add_attribute(hdr, RTA_PREFSRC, chunk, sizeof(request));
1729         if (gateway && gateway->get_family(gateway) == src_ip->get_family(src_ip))
1730         {
1731                 chunk = gateway->get_address(gateway);
1732                 netlink_add_attribute(hdr, RTA_GATEWAY, chunk, sizeof(request));
1733         }
1734         ifindex = get_interface_index(this, if_name);
1735         chunk.ptr = (char*)&ifindex;
1736         chunk.len = sizeof(ifindex);
1737         netlink_add_attribute(hdr, RTA_OIF, chunk, sizeof(request));
1738
1739         return this->socket->send_ack(this->socket, hdr);
1740 }
1741
1742 METHOD(kernel_net_t, add_route, status_t,
1743         private_kernel_netlink_net_t *this, chunk_t dst_net, u_int8_t prefixlen,
1744         host_t *gateway, host_t *src_ip, char *if_name)
1745 {
1746         status_t status;
1747         route_entry_t *found, route = {
1748                 .dst_net = dst_net,
1749                 .prefixlen = prefixlen,
1750                 .gateway = gateway,
1751                 .src_ip = src_ip,
1752                 .if_name = if_name,
1753         };
1754
1755         this->mutex->lock(this->mutex);
1756         found = this->routes->get(this->routes, &route);
1757         if (found)
1758         {
1759                 this->mutex->unlock(this->mutex);
1760                 return ALREADY_DONE;
1761         }
1762         found = route_entry_clone(&route);
1763         this->routes->put(this->routes, found, found);
1764         status = manage_srcroute(this, RTM_NEWROUTE, NLM_F_CREATE | NLM_F_EXCL,
1765                                                          dst_net, prefixlen, gateway, src_ip, if_name);
1766         this->mutex->unlock(this->mutex);
1767         return status;
1768 }
1769
1770 METHOD(kernel_net_t, del_route, status_t,
1771         private_kernel_netlink_net_t *this, chunk_t dst_net, u_int8_t prefixlen,
1772         host_t *gateway, host_t *src_ip, char *if_name)
1773 {
1774         status_t status;
1775         route_entry_t *found, route = {
1776                 .dst_net = dst_net,
1777                 .prefixlen = prefixlen,
1778                 .gateway = gateway,
1779                 .src_ip = src_ip,
1780                 .if_name = if_name,
1781         };
1782
1783         this->mutex->lock(this->mutex);
1784         found = this->routes->get(this->routes, &route);
1785         if (!found)
1786         {
1787                 this->mutex->unlock(this->mutex);
1788                 return NOT_FOUND;
1789         }
1790         this->routes->remove(this->routes, found);
1791         route_entry_destroy(found);
1792         status = manage_srcroute(this, RTM_DELROUTE, 0, dst_net, prefixlen,
1793                                                          gateway, src_ip, if_name);
1794         this->mutex->unlock(this->mutex);
1795         return status;
1796 }
1797
1798 /**
1799  * Initialize a list of local addresses.
1800  */
1801 static status_t init_address_list(private_kernel_netlink_net_t *this)
1802 {
1803         netlink_buf_t request;
1804         struct nlmsghdr *out, *current, *in;
1805         struct rtgenmsg *msg;
1806         size_t len;
1807         enumerator_t *ifaces, *addrs;
1808         iface_entry_t *iface;
1809         addr_entry_t *addr;
1810
1811         DBG2(DBG_KNL, "known interfaces and IP addresses:");
1812
1813         memset(&request, 0, sizeof(request));
1814
1815         in = (struct nlmsghdr*)&request;
1816         in->nlmsg_len = NLMSG_LENGTH(sizeof(struct rtgenmsg));
1817         in->nlmsg_flags = NLM_F_REQUEST | NLM_F_MATCH | NLM_F_ROOT;
1818         msg = (struct rtgenmsg*)NLMSG_DATA(in);
1819         msg->rtgen_family = AF_UNSPEC;
1820
1821         /* get all links */
1822         in->nlmsg_type = RTM_GETLINK;
1823         if (this->socket->send(this->socket, in, &out, &len) != SUCCESS)
1824         {
1825                 return FAILED;
1826         }
1827         current = out;
1828         while (NLMSG_OK(current, len))
1829         {
1830                 switch (current->nlmsg_type)
1831                 {
1832                         case NLMSG_DONE:
1833                                 break;
1834                         case RTM_NEWLINK:
1835                                 process_link(this, current, FALSE);
1836                                 /* fall through */
1837                         default:
1838                                 current = NLMSG_NEXT(current, len);
1839                                 continue;
1840                 }
1841                 break;
1842         }
1843         free(out);
1844
1845         /* get all interface addresses */
1846         in->nlmsg_type = RTM_GETADDR;
1847         if (this->socket->send(this->socket, in, &out, &len) != SUCCESS)
1848         {
1849                 return FAILED;
1850         }
1851         current = out;
1852         while (NLMSG_OK(current, len))
1853         {
1854                 switch (current->nlmsg_type)
1855                 {
1856                         case NLMSG_DONE:
1857                                 break;
1858                         case RTM_NEWADDR:
1859                                 process_addr(this, current, FALSE);
1860                                 /* fall through */
1861                         default:
1862                                 current = NLMSG_NEXT(current, len);
1863                                 continue;
1864                 }
1865                 break;
1866         }
1867         free(out);
1868
1869         this->mutex->lock(this->mutex);
1870         ifaces = this->ifaces->create_enumerator(this->ifaces);
1871         while (ifaces->enumerate(ifaces, &iface))
1872         {
1873                 if (iface_entry_up_and_usable(iface))
1874                 {
1875                         DBG2(DBG_KNL, "  %s", iface->ifname);
1876                         addrs = iface->addrs->create_enumerator(iface->addrs);
1877                         while (addrs->enumerate(addrs, (void**)&addr))
1878                         {
1879                                 DBG2(DBG_KNL, "    %H", addr->ip);
1880                         }
1881                         addrs->destroy(addrs);
1882                 }
1883         }
1884         ifaces->destroy(ifaces);
1885         this->mutex->unlock(this->mutex);
1886         return SUCCESS;
1887 }
1888
1889 /**
1890  * create or delete a rule to use our routing table
1891  */
1892 static status_t manage_rule(private_kernel_netlink_net_t *this, int nlmsg_type,
1893                                                         int family, u_int32_t table, u_int32_t prio)
1894 {
1895         netlink_buf_t request;
1896         struct nlmsghdr *hdr;
1897         struct rtmsg *msg;
1898         chunk_t chunk;
1899
1900         memset(&request, 0, sizeof(request));
1901         hdr = (struct nlmsghdr*)request;
1902         hdr->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK;
1903         hdr->nlmsg_type = nlmsg_type;
1904         if (nlmsg_type == RTM_NEWRULE)
1905         {
1906                 hdr->nlmsg_flags |= NLM_F_CREATE | NLM_F_EXCL;
1907         }
1908         hdr->nlmsg_len = NLMSG_LENGTH(sizeof(struct rtmsg));
1909
1910         msg = (struct rtmsg*)NLMSG_DATA(hdr);
1911         msg->rtm_table = table;
1912         msg->rtm_family = family;
1913         msg->rtm_protocol = RTPROT_BOOT;
1914         msg->rtm_scope = RT_SCOPE_UNIVERSE;
1915         msg->rtm_type = RTN_UNICAST;
1916
1917         chunk = chunk_from_thing(prio);
1918         netlink_add_attribute(hdr, RTA_PRIORITY, chunk, sizeof(request));
1919
1920         return this->socket->send_ack(this->socket, hdr);
1921 }
1922
1923 /**
1924  * check for kernel features (currently only via version number)
1925  */
1926 static void check_kernel_features(private_kernel_netlink_net_t *this)
1927 {
1928         struct utsname utsname;
1929         int a, b, c;
1930
1931         if (uname(&utsname) == 0)
1932         {
1933                 switch(sscanf(utsname.release, "%d.%d.%d", &a, &b, &c))
1934                 {
1935                         case 3:
1936                                 if (a == 2)
1937                                 {
1938                                         DBG2(DBG_KNL, "detected Linux %d.%d.%d, no support for "
1939                                                  "RTA_PREFSRC for IPv6 routes", a, b, c);
1940                                         break;
1941                                 }
1942                                 /* fall-through */
1943                         case 2:
1944                                 /* only 3.x+ uses two part version numbers */
1945                                 this->rta_prefsrc_for_ipv6 = TRUE;
1946                                 break;
1947                         default:
1948                                 break;
1949                 }
1950         }
1951 }
1952
1953 METHOD(kernel_net_t, destroy, void,
1954         private_kernel_netlink_net_t *this)
1955 {
1956         enumerator_t *enumerator;
1957         route_entry_t *route;
1958
1959         if (this->routing_table)
1960         {
1961                 manage_rule(this, RTM_DELRULE, AF_INET, this->routing_table,
1962                                         this->routing_table_prio);
1963                 manage_rule(this, RTM_DELRULE, AF_INET6, this->routing_table,
1964                                         this->routing_table_prio);
1965         }
1966         if (this->socket_events > 0)
1967         {
1968                 close(this->socket_events);
1969         }
1970         enumerator = this->routes->create_enumerator(this->routes);
1971         while (enumerator->enumerate(enumerator, NULL, (void**)&route))
1972         {
1973                 manage_srcroute(this, RTM_DELROUTE, 0, route->dst_net, route->prefixlen,
1974                                                 route->gateway, route->src_ip, route->if_name);
1975                 route_entry_destroy(route);
1976         }
1977         enumerator->destroy(enumerator);
1978         this->routes->destroy(this->routes);
1979         DESTROY_IF(this->socket);
1980
1981         net_changes_clear(this);
1982         this->net_changes->destroy(this->net_changes);
1983         this->net_changes_lock->destroy(this->net_changes_lock);
1984
1985         this->ifaces->destroy_function(this->ifaces, (void*)iface_entry_destroy);
1986         this->rt_exclude->destroy(this->rt_exclude);
1987         this->condvar->destroy(this->condvar);
1988         this->mutex->destroy(this->mutex);
1989         free(this);
1990 }
1991
1992 /*
1993  * Described in header.
1994  */
1995 kernel_netlink_net_t *kernel_netlink_net_create()
1996 {
1997         private_kernel_netlink_net_t *this;
1998         enumerator_t *enumerator;
1999         bool register_for_events = TRUE;
2000         char *exclude;
2001
2002         INIT(this,
2003                 .public = {
2004                         .interface = {
2005                                 .get_interface = _get_interface_name,
2006                                 .create_address_enumerator = _create_address_enumerator,
2007                                 .get_source_addr = _get_source_addr,
2008                                 .get_nexthop = _get_nexthop,
2009                                 .add_ip = _add_ip,
2010                                 .del_ip = _del_ip,
2011                                 .add_route = _add_route,
2012                                 .del_route = _del_route,
2013                                 .destroy = _destroy,
2014                         },
2015                 },
2016                 .socket = netlink_socket_create(NETLINK_ROUTE),
2017                 .rt_exclude = linked_list_create(),
2018                 .routes = hashtable_create((hashtable_hash_t)route_entry_hash,
2019                                                                    (hashtable_equals_t)route_entry_equals, 16),
2020                 .net_changes = hashtable_create(
2021                                                                    (hashtable_hash_t)net_change_hash,
2022                                                                    (hashtable_equals_t)net_change_equals, 16),
2023                 .net_changes_lock = mutex_create(MUTEX_TYPE_DEFAULT),
2024                 .ifaces = linked_list_create(),
2025                 .mutex = mutex_create(MUTEX_TYPE_RECURSIVE),
2026                 .condvar = condvar_create(CONDVAR_TYPE_DEFAULT),
2027                 .routing_table = lib->settings->get_int(lib->settings,
2028                                 "%s.routing_table", ROUTING_TABLE, hydra->daemon),
2029                 .routing_table_prio = lib->settings->get_int(lib->settings,
2030                                 "%s.routing_table_prio", ROUTING_TABLE_PRIO, hydra->daemon),
2031                 .process_route = lib->settings->get_bool(lib->settings,
2032                                 "%s.process_route", TRUE, hydra->daemon),
2033                 .install_virtual_ip = lib->settings->get_bool(lib->settings,
2034                                 "%s.install_virtual_ip", TRUE, hydra->daemon),
2035         );
2036         timerclear(&this->last_route_reinstall);
2037         timerclear(&this->last_roam);
2038
2039         check_kernel_features(this);
2040
2041         if (streq(hydra->daemon, "starter"))
2042         {       /* starter has no threads, so we do not register for kernel events */
2043                 register_for_events = FALSE;
2044         }
2045
2046         exclude = lib->settings->get_str(lib->settings,
2047                                         "%s.ignore_routing_tables", NULL, hydra->daemon);
2048         if (exclude)
2049         {
2050                 char *token;
2051                 uintptr_t table;
2052
2053                 enumerator = enumerator_create_token(exclude, " ", " ");
2054                 while (enumerator->enumerate(enumerator, &token))
2055                 {
2056                         errno = 0;
2057                         table = strtoul(token, NULL, 10);
2058
2059                         if (errno == 0)
2060                         {
2061                                 this->rt_exclude->insert_last(this->rt_exclude, (void*)table);
2062                         }
2063                 }
2064                 enumerator->destroy(enumerator);
2065         }
2066
2067         if (register_for_events)
2068         {
2069                 struct sockaddr_nl addr;
2070
2071                 memset(&addr, 0, sizeof(addr));
2072                 addr.nl_family = AF_NETLINK;
2073
2074                 /* create and bind RT socket for events (address/interface/route changes) */
2075                 this->socket_events = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
2076                 if (this->socket_events < 0)
2077                 {
2078                         DBG1(DBG_KNL, "unable to create RT event socket");
2079                         destroy(this);
2080                         return NULL;
2081                 }
2082                 addr.nl_groups = RTMGRP_IPV4_IFADDR | RTMGRP_IPV6_IFADDR |
2083                                                  RTMGRP_IPV4_ROUTE | RTMGRP_IPV6_ROUTE | RTMGRP_LINK;
2084                 if (bind(this->socket_events, (struct sockaddr*)&addr, sizeof(addr)))
2085                 {
2086                         DBG1(DBG_KNL, "unable to bind RT event socket");
2087                         destroy(this);
2088                         return NULL;
2089                 }
2090
2091                 lib->processor->queue_job(lib->processor,
2092                         (job_t*)callback_job_create_with_prio(
2093                                         (callback_job_cb_t)receive_events, this, NULL,
2094                                         (callback_job_cancel_t)return_false, JOB_PRIO_CRITICAL));
2095         }
2096
2097         if (init_address_list(this) != SUCCESS)
2098         {
2099                 DBG1(DBG_KNL, "unable to get interface list");
2100                 destroy(this);
2101                 return NULL;
2102         }
2103
2104         if (this->routing_table)
2105         {
2106                 if (manage_rule(this, RTM_NEWRULE, AF_INET, this->routing_table,
2107                                                 this->routing_table_prio) != SUCCESS)
2108                 {
2109                         DBG1(DBG_KNL, "unable to create IPv4 routing table rule");
2110                 }
2111                 if (manage_rule(this, RTM_NEWRULE, AF_INET6, this->routing_table,
2112                                                 this->routing_table_prio) != SUCCESS)
2113                 {
2114                         DBG1(DBG_KNL, "unable to create IPv6 routing table rule");
2115                 }
2116         }
2117
2118         return &this->public;
2119 }