git.meshlink.io Git - catta/blob - avahi-core/iface.c

   1 /* $Id$ */
   2
   3 /***
   4   This file is part of avahi.
   5
   6   avahi is free software; you can redistribute it and/or modify it
   7   under the terms of the GNU Lesser General Public License as
   8   published by the Free Software Foundation; either version 2.1 of the
   9   License, or (at your option) any later version.
  10
  11   avahi is distributed in the hope that it will be useful, but WITHOUT
  12   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  13   or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General
  14   Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public
  17   License along with avahi; if not, write to the Free Software
  18   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  19   USA.
  20 ***/
  21
  22 #ifdef HAVE_CONFIG_H
  23 #include <config.h>
  24 #endif
  25
  26 #include <string.h>
  27 #include <sys/socket.h>
  28 #include <asm/types.h>
  29 #include <linux/netlink.h>
  30 #include <linux/rtnetlink.h>
  31 #include <errno.h>
  32 #include <net/if.h>
  33
  34 #include "iface.h"
  35 #include "netlink.h"
  36 #include "dns.h"
  37 #include "socket.h"
  38 #include "announce.h"
  39
  40 static void update_address_rr(AvahiInterfaceMonitor *m, AvahiInterfaceAddress *a, int remove) {
  41     g_assert(m);
  42     g_assert(a);
  43
  44     if (!avahi_interface_address_relevant(a) || remove) {
  45         if (a->entry_group) {
  46             avahi_entry_group_free(a->entry_group);
  47             a->entry_group = NULL;
  48         }
  49     } else {
  50         if (!a->entry_group) {
  51             a->entry_group = avahi_entry_group_new(m->server, NULL, NULL);
  52             avahi_server_add_address(m->server, a->entry_group, a->interface->hardware->index, AF_UNSPEC, 0, NULL, &a->address);
  53             avahi_entry_group_commit(a->entry_group);
  54         }
  55     }
  56 }
  57
  58 static void update_interface_rr(AvahiInterfaceMonitor *m, AvahiInterface *i, int remove) {
  59     AvahiInterfaceAddress *a;
  60     g_assert(m);
  61     g_assert(i);
  62
  63     for (a = i->addresses; a; a = a->address_next)
  64         update_address_rr(m, a, remove);
  65 }
  66
  67 static void update_hw_interface_rr(AvahiInterfaceMonitor *m, AvahiHwInterface *hw, int remove) {
  68     AvahiInterface *i;
  69
  70     g_assert(m);
  71     g_assert(hw);
  72
  73     for (i = hw->interfaces; i; i = i->by_hardware_next)
  74         update_interface_rr(m, i, remove);
  75 }
  76
  77 static void free_address(AvahiInterfaceMonitor *m, AvahiInterfaceAddress *a) {
  78     g_assert(m);
  79     g_assert(a);
  80     g_assert(a->interface);
  81
  82     AVAHI_LLIST_REMOVE(AvahiInterfaceAddress, address, a->interface->addresses, a);
  83
  84     if (a->entry_group)
  85         avahi_entry_group_free(a->entry_group);
  86
  87     g_free(a);
  88 }
  89
  90 static void free_interface(AvahiInterfaceMonitor *m, AvahiInterface *i, gboolean send_goodbye) {
  91     g_assert(m);
  92     g_assert(i);
  93
  94     g_message("removing interface %s.%i", i->hardware->name, i->protocol);
  95     avahi_goodbye_interface(m->server, i, send_goodbye);
  96     g_message("flushing...");
  97     avahi_packet_scheduler_flush_responses(i->scheduler);
  98     g_message("done");
  99
 100     g_assert(!i->announcements);
 101
 102     while (i->addresses)
 103         free_address(m, i->addresses);
 104
 105     avahi_packet_scheduler_free(i->scheduler);
 106     avahi_cache_free(i->cache);
 107
 108     AVAHI_LLIST_REMOVE(AvahiInterface, interface, m->interfaces, i);
 109     AVAHI_LLIST_REMOVE(AvahiInterface, by_hardware, i->hardware->interfaces, i);
 110
 111     g_free(i);
 112 }
 113
 114 static void free_hw_interface(AvahiInterfaceMonitor *m, AvahiHwInterface *hw, gboolean send_goodbye) {
 115     g_assert(m);
 116     g_assert(hw);
 117
 118     while (hw->interfaces)
 119         free_interface(m, hw->interfaces, send_goodbye);
 120
 121     AVAHI_LLIST_REMOVE(AvahiHwInterface, hardware, m->hw_interfaces, hw);
 122     g_hash_table_remove(m->hash_table, &hw->index);
 123
 124     g_free(hw->name);
 125     g_free(hw);
 126 }
 127
 128 static AvahiInterfaceAddress* get_address(AvahiInterfaceMonitor *m, AvahiInterface *i, const AvahiAddress *raddr) {
 129     AvahiInterfaceAddress *ia;
 130
 131     g_assert(m);
 132     g_assert(i);
 133     g_assert(raddr);
 134
 135     for (ia = i->addresses; ia; ia = ia->address_next)
 136         if (avahi_address_cmp(&ia->address, raddr) == 0)
 137             return ia;
 138
 139     return NULL;
 140 }
 141
 142 static int netlink_list_items(AvahiNetlink *nl, guint16 type, guint *ret_seq) {
 143     struct nlmsghdr *n;
 144     struct rtgenmsg *gen;
 145     guint8 req[1024];
 146
 147     memset(&req, 0, sizeof(req));
 148     n = (struct nlmsghdr*) req;
 149     n->nlmsg_len = NLMSG_LENGTH(sizeof(struct rtgenmsg));
 150     n->nlmsg_type = type;
 151     n->nlmsg_flags = NLM_F_ROOT|NLM_F_MATCH|NLM_F_REQUEST;
 152     n->nlmsg_pid = 0;
 153
 154     gen = NLMSG_DATA(n);
 155     memset(gen, 0, sizeof(struct rtgenmsg));
 156     gen->rtgen_family = AF_UNSPEC;
 157
 158     return avahi_netlink_send(nl, n, ret_seq);
 159 }
 160
 161 static void new_interface(AvahiInterfaceMonitor *m, AvahiHwInterface *hw, guchar protocol) {
 162     AvahiInterface *i;
 163
 164     g_assert(m);
 165     g_assert(hw);
 166     g_assert(protocol != AF_UNSPEC);
 167
 168     i = g_new(AvahiInterface, 1);
 169     i->monitor = m;
 170     i->hardware = hw;
 171     i->protocol = protocol;
 172     i->announcing = FALSE;
 173
 174     AVAHI_LLIST_HEAD_INIT(AvahiInterfaceAddress, i->addresses);
 175     AVAHI_LLIST_HEAD_INIT(AvahiAnnouncement, i->announcements);
 176
 177     i->cache = avahi_cache_new(m->server, i);
 178     i->scheduler = avahi_packet_scheduler_new(m->server, i);
 179
 180     AVAHI_LLIST_PREPEND(AvahiInterface, by_hardware, hw->interfaces, i);
 181     AVAHI_LLIST_PREPEND(AvahiInterface, interface, m->interfaces, i);
 182 }
 183
 184 static void check_interface_relevant(AvahiInterfaceMonitor *m, AvahiInterface *i) {
 185     gboolean b;
 186
 187     g_assert(m);
 188     g_assert(i);
 189
 190     b = avahi_interface_relevant(i);
 191
 192     if (b && !i->announcing) {
 193         g_message("New relevant interface %s.%i", i->hardware->name, i->protocol);
 194
 195         if (i->protocol == AF_INET)
 196             avahi_mdns_mcast_join_ipv4 (i->hardware->index, m->server->fd_ipv4);
 197         if (i->protocol == AF_INET6)
 198             avahi_mdns_mcast_join_ipv6 (i->hardware->index, m->server->fd_ipv6);
 199
 200         i->announcing = TRUE;
 201         avahi_announce_interface(m->server, i);
 202     } else if (!b && i->announcing) {
 203         g_message("Interface %s.%i no longer relevant", i->hardware->name, i->protocol);
 204
 205         avahi_goodbye_interface(m->server, i, FALSE);
 206
 207         if (i->protocol == AF_INET)
 208             avahi_mdns_mcast_leave_ipv4 (i->hardware->index, m->server->fd_ipv4);
 209         if (i->protocol == AF_INET6)
 210             avahi_mdns_mcast_leave_ipv6 (i->hardware->index, m->server->fd_ipv6);
 211
 212         i->announcing = FALSE;
 213     }
 214 }
 215
 216 static void check_hw_interface_relevant(AvahiInterfaceMonitor *m, AvahiHwInterface *hw) {
 217     AvahiInterface *i;
 218
 219     g_assert(m);
 220     g_assert(hw);
 221
 222     for (i = hw->interfaces; i; i = i->by_hardware_next)
 223         check_interface_relevant(m, i);
 224 }
 225
 226 static void callback(AvahiNetlink *nl, struct nlmsghdr *n, gpointer userdata) {
 227     AvahiInterfaceMonitor *m = userdata;
 228
 229     g_assert(m);
 230     g_assert(n);
 231     g_assert(m->netlink == nl);
 232
 233     if (n->nlmsg_type == RTM_NEWLINK) {
 234         struct ifinfomsg *ifinfomsg = NLMSG_DATA(n);
 235         AvahiHwInterface *hw;
 236         struct rtattr *a = NULL;
 237         size_t l;
 238
 239         if (ifinfomsg->ifi_family != AF_UNSPEC)
 240             return;
 241
 242         if (!(hw = g_hash_table_lookup(m->hash_table, &ifinfomsg->ifi_index))) {
 243             hw = g_new(AvahiHwInterface, 1);
 244             hw->monitor = m;
 245             hw->name = NULL;
 246             hw->flags = 0;
 247             hw->mtu = 1500;
 248             hw->index = ifinfomsg->ifi_index;
 249
 250             AVAHI_LLIST_HEAD_INIT(AvahiInterface, hw->interfaces);
 251             AVAHI_LLIST_PREPEND(AvahiHwInterface, hardware, m->hw_interfaces, hw);
 252
 253             g_hash_table_insert(m->hash_table, &hw->index, hw);
 254
 255             if (m->server->fd_ipv4 >= 0)
 256                 new_interface(m, hw, AF_INET);
 257             if (m->server->fd_ipv6 >= 0)
 258                 new_interface(m, hw, AF_INET6);
 259         }
 260
 261         hw->flags = ifinfomsg->ifi_flags;
 262
 263         l = NLMSG_PAYLOAD(n, sizeof(struct ifinfomsg));
 264         a = IFLA_RTA(ifinfomsg);
 265
 266         while (RTA_OK(a, l)) {
 267             switch(a->rta_type) {
 268                 case IFLA_IFNAME:
 269                     g_free(hw->name);
 270                     hw->name = g_strndup(RTA_DATA(a), RTA_PAYLOAD(a));
 271                     break;
 272
 273                 case IFLA_MTU:
 274                     g_assert(RTA_PAYLOAD(a) == sizeof(unsigned int));
 275                     hw->mtu = *((unsigned int*) RTA_DATA(a));
 276                     break;
 277
 278                 default:
 279                     ;
 280             }
 281
 282             a = RTA_NEXT(a, l);
 283         }
 284
 285         update_hw_interface_rr(m, hw, FALSE);
 286         check_hw_interface_relevant(m, hw);
 287
 288     } else if (n->nlmsg_type == RTM_DELLINK) {
 289         struct ifinfomsg *ifinfomsg = NLMSG_DATA(n);
 290         AvahiHwInterface *hw;
 291
 292         if (ifinfomsg->ifi_family != AF_UNSPEC)
 293             return;
 294
 295         if (!(hw = avahi_interface_monitor_get_hw_interface(m, ifinfomsg->ifi_index)))
 296             return;
 297
 298         update_hw_interface_rr(m, hw, TRUE);
 299         free_hw_interface(m, hw, FALSE);
 300
 301     } else if (n->nlmsg_type == RTM_NEWADDR || n->nlmsg_type == RTM_DELADDR) {
 302
 303         struct ifaddrmsg *ifaddrmsg = NLMSG_DATA(n);
 304         AvahiInterface *i;
 305         struct rtattr *a = NULL;
 306         size_t l;
 307         AvahiAddress raddr;
 308         int raddr_valid = 0;
 309
 310         if (ifaddrmsg->ifa_family != AF_INET && ifaddrmsg->ifa_family != AF_INET6)
 311             return;
 312
 313         if (!(i = (AvahiInterface*) avahi_interface_monitor_get_interface(m, ifaddrmsg->ifa_index, ifaddrmsg->ifa_family)))
 314             return;
 315
 316         raddr.family = ifaddrmsg->ifa_family;
 317
 318         l = NLMSG_PAYLOAD(n, sizeof(struct ifinfomsg));
 319         a = IFA_RTA(ifaddrmsg);
 320
 321         while (RTA_OK(a, l)) {
 322             switch(a->rta_type) {
 323                 case IFA_ADDRESS:
 324                     if ((raddr.family == AF_INET6 && RTA_PAYLOAD(a) != 16) ||
 325                         (raddr.family == AF_INET && RTA_PAYLOAD(a) != 4))
 326                         return;
 327
 328                     memcpy(raddr.data.data, RTA_DATA(a), RTA_PAYLOAD(a));
 329                     raddr_valid = 1;
 330
 331                     break;
 332
 333                 default:
 334                     ;
 335             }
 336
 337             a = RTA_NEXT(a, l);
 338         }
 339
 340
 341         if (!raddr_valid)
 342             return;
 343
 344         if (n->nlmsg_type == RTM_NEWADDR) {
 345             AvahiInterfaceAddress *addr;
 346
 347             if (!(addr = get_address(m, i, &raddr))) {
 348                 addr = g_new(AvahiInterfaceAddress, 1);
 349                 addr->monitor = m;
 350                 addr->address = raddr;
 351                 addr->interface = i;
 352                 addr->entry_group = NULL;
 353
 354                 AVAHI_LLIST_PREPEND(AvahiInterfaceAddress, address, i->addresses, addr);
 355             }
 356
 357             addr->flags = ifaddrmsg->ifa_flags;
 358             addr->scope = ifaddrmsg->ifa_scope;
 359
 360             update_address_rr(m, addr, FALSE);
 361             check_interface_relevant(m, i);
 362         } else {
 363             AvahiInterfaceAddress *addr;
 364
 365             if (!(addr = get_address(m, i, &raddr)))
 366                 return;
 367
 368             update_address_rr(m, addr, TRUE);
 369             free_address(m, addr);
 370
 371             check_interface_relevant(m, i);
 372         }
 373
 374     } else if (n->nlmsg_type == NLMSG_DONE) {
 375
 376         if (m->list == LIST_IFACE) {
 377             m->list = LIST_DONE;
 378
 379             if (netlink_list_items(m->netlink, RTM_GETADDR, &m->query_addr_seq) < 0)
 380                 g_warning("NETLINK: Failed to list addrs: %s", strerror(errno));
 381             else
 382                 m->list = LIST_ADDR;
 383         } else {
 384             m->list = LIST_DONE;
 385             g_message("Enumeration complete");
 386         }
 387
 388     } else if (n->nlmsg_type == NLMSG_ERROR && (n->nlmsg_seq == m->query_link_seq || n->nlmsg_seq == m->query_addr_seq)) {
 389         struct nlmsgerr *e = NLMSG_DATA (n);
 390
 391         if (e->error)
 392             g_warning("NETLINK: Failed to browse: %s", strerror(-e->error));
 393     }
 394 }
 395
 396 AvahiInterfaceMonitor *avahi_interface_monitor_new(AvahiServer *s) {
 397     AvahiInterfaceMonitor *m = NULL;
 398
 399     m = g_new0(AvahiInterfaceMonitor, 1);
 400     m->server = s;
 401     if (!(m->netlink = avahi_netlink_new(s->context, G_PRIORITY_DEFAULT-10, RTMGRP_LINK|RTMGRP_IPV4_IFADDR|RTMGRP_IPV6_IFADDR, callback, m)))
 402         goto fail;
 403
 404     m->hash_table = g_hash_table_new(g_int_hash, g_int_equal);
 405
 406     AVAHI_LLIST_HEAD_INIT(AvahiInterface, m->interfaces);
 407     AVAHI_LLIST_HEAD_INIT(AvahiHwInterface, m->hw_interfaces);
 408
 409     if (netlink_list_items(m->netlink, RTM_GETLINK, &m->query_link_seq) < 0)
 410         goto fail;
 411
 412     m->list = LIST_IFACE;
 413
 414     return m;
 415
 416 fail:
 417     avahi_interface_monitor_free(m);
 418     return NULL;
 419 }
 420
 421 void avahi_interface_monitor_sync(AvahiInterfaceMonitor *m) {
 422     g_assert(m);
 423
 424     while (m->list != LIST_DONE) {
 425         if (!avahi_netlink_work(m->netlink, TRUE))
 426             break;
 427     }
 428 }
 429
 430 void avahi_interface_monitor_free(AvahiInterfaceMonitor *m) {
 431     g_assert(m);
 432
 433     while (m->hw_interfaces)
 434         free_hw_interface(m, m->hw_interfaces, TRUE);
 435
 436     g_assert(!m->interfaces);
 437
 438
 439     if (m->netlink)
 440         avahi_netlink_free(m->netlink);
 441
 442     if (m->hash_table)
 443         g_hash_table_destroy(m->hash_table);
 444
 445     g_free(m);
 446 }
 447
 448
 449 AvahiInterface* avahi_interface_monitor_get_interface(AvahiInterfaceMonitor *m, gint index, guchar protocol) {
 450     AvahiHwInterface *hw;
 451     AvahiInterface *i;
 452
 453     g_assert(m);
 454     g_assert(index > 0);
 455     g_assert(protocol != AF_UNSPEC);
 456
 457     if (!(hw = avahi_interface_monitor_get_hw_interface(m, index)))
 458         return NULL;
 459
 460     for (i = hw->interfaces; i; i = i->by_hardware_next)
 461         if (i->protocol == protocol)
 462             return i;
 463
 464     return NULL;
 465 }
 466
 467 AvahiHwInterface* avahi_interface_monitor_get_hw_interface(AvahiInterfaceMonitor *m, gint index) {
 468     g_assert(m);
 469     g_assert(index > 0);
 470
 471     return g_hash_table_lookup(m->hash_table, &index);
 472 }
 473
 474
 475 void avahi_interface_send_packet_unicast(AvahiInterface *i, AvahiDnsPacket *p, const AvahiAddress *a, guint16 port) {
 476     g_assert(i);
 477     g_assert(p);
 478     char t[64];
 479
 480     if (!avahi_interface_relevant(i))
 481         return;
 482
 483     g_assert(!a || a->family == i->protocol);
 484
 485     if (a)
 486         g_message("unicast sending on '%s.%i' to %s:%u", i->hardware->name, i->protocol, avahi_address_snprint(t, sizeof(t), a), port);
 487     else
 488         g_message("multicast sending on '%s.%i'", i->hardware->name, i->protocol);
 489
 490     if (i->protocol == AF_INET && i->monitor->server->fd_ipv4 >= 0)
 491         avahi_send_dns_packet_ipv4(i->monitor->server->fd_ipv4, i->hardware->index, p, a ? &a->data.ipv4 : NULL, port);
 492     else if (i->protocol == AF_INET6 && i->monitor->server->fd_ipv6 >= 0)
 493         avahi_send_dns_packet_ipv6(i->monitor->server->fd_ipv6, i->hardware->index, p, a ? &a->data.ipv6 : NULL, port);
 494 }
 495
 496 void avahi_interface_send_packet(AvahiInterface *i, AvahiDnsPacket *p) {
 497     g_assert(i);
 498     g_assert(p);
 499
 500     avahi_interface_send_packet_unicast(i, p, NULL, 0);
 501 }
 502
 503 gboolean avahi_interface_post_query(AvahiInterface *i, AvahiKey *key, gboolean immediately) {
 504     g_assert(i);
 505     g_assert(key);
 506
 507     if (avahi_interface_relevant(i))
 508         return avahi_packet_scheduler_post_query(i->scheduler, key, immediately);
 509
 510     return FALSE;
 511 }
 512
 513 gboolean avahi_interface_post_response(AvahiInterface *i, const AvahiAddress *a, AvahiRecord *record, gboolean flush_cache, gboolean immediately) {
 514     g_assert(i);
 515     g_assert(record);
 516
 517     if (avahi_interface_relevant(i))
 518         return avahi_packet_scheduler_post_response(i->scheduler, a, record, flush_cache, immediately);
 519
 520     return FALSE;
 521 }
 522
 523 gboolean avahi_interface_post_probe(AvahiInterface *i, AvahiRecord *record, gboolean immediately) {
 524     g_assert(i);
 525     g_assert(record);
 526
 527     if (avahi_interface_relevant(i))
 528         return avahi_packet_scheduler_post_probe(i->scheduler, record, immediately);
 529
 530     return FALSE;
 531 }
 532
 533 void avahi_dump_caches(AvahiInterfaceMonitor *m, FILE *f) {
 534     AvahiInterface *i;
 535     g_assert(m);
 536
 537     for (i = m->interfaces; i; i = i->interface_next) {
 538         if (avahi_interface_relevant(i)) {
 539             fprintf(f, "\n;;; INTERFACE %s.%i ;;;\n", i->hardware->name, i->protocol);
 540             avahi_cache_dump(i->cache, f);
 541         }
 542     }
 543     fprintf(f, "\n");
 544 }
 545
 546 gboolean avahi_interface_relevant(AvahiInterface *i) {
 547     g_assert(i);
 548
 549     return
 550         (i->hardware->flags & IFF_UP) &&
 551         (i->hardware->flags & IFF_RUNNING) &&
 552         !(i->hardware->flags & IFF_LOOPBACK) &&
 553         (i->hardware->flags & IFF_MULTICAST) &&
 554         i->addresses;
 555 }
 556
 557 gboolean avahi_interface_address_relevant(AvahiInterfaceAddress *a) {
 558     g_assert(a);
 559
 560     return a->scope == RT_SCOPE_UNIVERSE;
 561 }
 562
 563
 564 gboolean avahi_interface_match(AvahiInterface *i, gint index, guchar protocol) {
 565     g_assert(i);
 566
 567     if (index > 0 && index != i->hardware->index)
 568         return FALSE;
 569
 570     if (protocol != AF_UNSPEC && protocol != i->protocol)
 571         return FALSE;
 572
 573     return TRUE;
 574 }
 575
 576
 577 void avahi_interface_monitor_walk(AvahiInterfaceMonitor *m, gint interface, guchar protocol, AvahiInterfaceMonitorWalkCallback callback, gpointer userdata) {
 578     g_assert(m);
 579     g_assert(callback);
 580
 581     if (interface > 0) {
 582         if (protocol != AF_UNSPEC) {
 583             AvahiInterface *i;
 584
 585             if ((i = avahi_interface_monitor_get_interface(m, interface, protocol)))
 586                 callback(m, i, userdata);
 587
 588         } else {
 589             AvahiHwInterface *hw;
 590             AvahiInterface *i;
 591
 592             if ((hw = avahi_interface_monitor_get_hw_interface(m, interface)))
 593                 for (i = hw->interfaces; i; i = i->by_hardware_next)
 594                     if (avahi_interface_match(i, interface, protocol))
 595                         callback(m, i, userdata);
 596         }
 597
 598     } else {
 599         AvahiInterface *i;
 600
 601         for (i = m->interfaces; i; i = i->interface_next)
 602             if (avahi_interface_match(i, interface, protocol))
 603                 callback(m, i, userdata);
 604     }
 605 }