1 #include <sys/socket.h>
4 #include <sys/utsname.h>
11 #include "subscribe.h"
13 static void free_entry(flxServer*s, flxEntry *e) {
19 flx_goodbye_entry(s, e, TRUE);
21 /* Remove from linked list */
22 FLX_LLIST_REMOVE(flxEntry, entries, s->entries, e);
24 /* Remove from hash table indexed by name */
25 t = g_hash_table_lookup(s->entries_by_key, e->record->key);
26 FLX_LLIST_REMOVE(flxEntry, by_key, t, e);
28 g_hash_table_replace(s->entries_by_key, t->record->key, t);
30 g_hash_table_remove(s->entries_by_key, e->record->key);
32 /* Remove from associated group */
34 FLX_LLIST_REMOVE(flxEntry, by_group, e->group->entries, e);
36 flx_record_unref(e->record);
40 static void free_group(flxServer *s, flxEntryGroup *g) {
45 free_entry(s, g->entries);
47 FLX_LLIST_REMOVE(flxEntryGroup, groups, s->groups, g);
51 static void cleanup_dead(flxServer *s) {
52 flxEntryGroup *g, *ng;
57 if (s->need_group_cleanup) {
58 for (g = s->groups; g; g = ng) {
65 s->need_group_cleanup = FALSE;
68 if (s->need_entry_cleanup) {
69 for (e = s->entries; e; e = ne) {
76 s->need_entry_cleanup = FALSE;
80 static void handle_query_key(flxServer *s, flxKey *k, flxInterface *i, const flxAddress *a) {
89 g_message("Handling query: %s", txt = flx_key_to_string(k));
92 flx_packet_scheduler_incoming_query(i->scheduler, k);
94 if (k->type == FLX_DNS_TYPE_ANY) {
96 /* Handle ANY query */
98 for (e = s->entries; e; e = e->entries_next)
99 if (!e->dead && flx_key_pattern_match(k, e->record->key) && flx_entry_registered(s, e, i))
100 flx_interface_post_response(i, a, e->record, e->flags & FLX_ENTRY_UNIQUE, FALSE);
103 /* Handle all other queries */
105 for (e = g_hash_table_lookup(s->entries_by_key, k); e; e = e->by_key_next)
106 if (!e->dead && flx_entry_registered(s, e, i))
107 flx_interface_post_response(i, a, e->record, e->flags & FLX_ENTRY_UNIQUE, FALSE);
111 static void withdraw_entry(flxServer *s, flxEntry *e) {
116 s->need_entry_cleanup = TRUE;
118 flx_goodbye_entry(s, e, FALSE);
121 flx_entry_group_run_callback(e->group, FLX_ENTRY_GROUP_COLLISION);
124 static void incoming_probe(flxServer *s, flxRecord *record, flxInterface *i) {
132 t = flx_record_to_string(record);
134 for (e = g_hash_table_lookup(s->entries_by_key, record->key); e; e = n) {
137 if (e->dead || !flx_record_equal_no_ttl(record, e->record))
140 if (flx_entry_registering(s, e, i)) {
142 if (flx_record_lexicographical_compare(record, e->record) > 0) {
143 withdraw_entry(s, e);
144 g_message("Recieved conflicting probe [%s]. Local host lost. Withdrawing.", t);
146 g_message("Recieved conflicting probe [%s]. Local host won.", t);
153 static void handle_query(flxServer *s, flxDnsPacket *p, flxInterface *i, const flxAddress *a) {
161 /* Handle the questions */
162 for (n = flx_dns_packet_get_field(p, FLX_DNS_FIELD_QDCOUNT); n > 0; n --) {
165 if (!(key = flx_dns_packet_consume_key(p))) {
166 g_warning("Packet too short (1)");
170 handle_query_key(s, key, i, a);
174 /* Known Answer Suppresion */
175 for (n = flx_dns_packet_get_field(p, FLX_DNS_FIELD_ANCOUNT); n > 0; n --) {
177 gboolean unique = FALSE;
179 if (!(record = flx_dns_packet_consume_record(p, &unique))) {
180 g_warning("Packet too short (2)");
184 flx_packet_scheduler_incoming_known_answer(i->scheduler, record, a);
185 flx_record_unref(record);
189 for (n = flx_dns_packet_get_field(p, FLX_DNS_FIELD_NSCOUNT); n > 0; n --) {
191 gboolean unique = FALSE;
193 if (!(record = flx_dns_packet_consume_record(p, &unique))) {
194 g_warning("Packet too short (3)");
198 if (record->key->type != FLX_DNS_TYPE_ANY)
199 incoming_probe(s, record, i);
201 flx_record_unref(record);
205 static gboolean handle_conflict(flxServer *s, flxInterface *i, flxRecord *record, const flxAddress *a) {
206 gboolean valid = TRUE;
214 t = flx_record_to_string(record);
216 for (e = g_hash_table_lookup(s->entries_by_key, record->key); e; e = n) {
222 if (flx_entry_registered(s, e, i)) {
224 gboolean equal = flx_record_equal_no_ttl(record, e->record);
226 /* Check whether there is a unique record conflict */
227 if (!equal && (e->flags & FLX_ENTRY_UNIQUE)) {
229 /* The lexicographically later data wins. */
230 if (flx_record_lexicographical_compare(record, e->record) > 0) {
231 withdraw_entry(s, e);
232 g_message("Recieved conflicting record [%s]. Local host lost. Withdrawing.", t);
234 /* Tell the other host that our entry is lexicographically later */
236 flx_interface_post_response(i, a, e->record, e->flags & FLX_ENTRY_UNIQUE, TRUE);
237 g_message("Recieved conflicting record [%s]. Local host won. Refreshing.", t);
240 /* Check wheter there is a TTL conflict */
241 } else if (equal && record->ttl <= e->record->ttl/2) {
242 /* Correct the TTL */
244 flx_interface_post_response(i, a, e->record, e->flags & FLX_ENTRY_UNIQUE, TRUE);
245 g_message("Recieved record with bad TTL [%s]. Refreshing.", t);
255 static void handle_response(flxServer *s, flxDnsPacket *p, flxInterface *i, const flxAddress *a) {
263 for (n = flx_dns_packet_get_field(p, FLX_DNS_FIELD_ANCOUNT) +
264 flx_dns_packet_get_field(p, FLX_DNS_FIELD_ARCOUNT); n > 0; n--) {
266 gboolean cache_flush = FALSE;
269 if (!(record = flx_dns_packet_consume_record(p, &cache_flush))) {
270 g_warning("Packet too short (4)");
274 if (record->key->type != FLX_DNS_TYPE_ANY) {
276 g_message("Handling response: %s", txt = flx_record_to_string(record));
279 if (handle_conflict(s, i, record, a)) {
280 flx_cache_update(i->cache, record, cache_flush, a);
281 flx_packet_scheduler_incoming_response(i->scheduler, record);
285 flx_record_unref(record);
289 static void dispatch_packet(flxServer *s, flxDnsPacket *p, struct sockaddr *sa, gint iface, gint ttl) {
298 g_message("new packet recieved.");
300 if (!(i = flx_interface_monitor_get_interface(s->monitor, iface, sa->sa_family))) {
301 g_warning("Recieved packet from invalid interface.");
306 g_warning("Recieved packet with invalid TTL on interface '%s.%i'.", i->hardware->name, i->protocol);
307 if (!s->ignore_bad_ttl)
311 if (sa->sa_family == AF_INET6) {
312 static const unsigned char ipv4_in_ipv6[] = {
313 0x00, 0x00, 0x00, 0x00,
314 0x00, 0x00, 0x00, 0x00,
315 0xFF, 0xFF, 0xFF, 0xFF };
317 if (memcmp(((struct sockaddr_in6*) sa)->sin6_addr.s6_addr, ipv4_in_ipv6, sizeof(ipv4_in_ipv6)) == 0) {
319 /* This is an IPv4 address encapsulated in IPv6, so let's ignore it. */
324 if (flx_dns_packet_check_valid(p) < 0) {
325 g_warning("Recieved invalid packet.");
329 flx_address_from_sockaddr(sa, &a);
331 if (flx_dns_packet_is_query(p)) {
333 if (flx_dns_packet_get_field(p, FLX_DNS_FIELD_QDCOUNT) == 0 ||
334 flx_dns_packet_get_field(p, FLX_DNS_FIELD_ARCOUNT) != 0) {
335 g_warning("Invalid query packet.");
339 handle_query(s, p, i, &a);
340 g_message("Handled query");
342 if (flx_dns_packet_get_field(p, FLX_DNS_FIELD_QDCOUNT) != 0 ||
343 flx_dns_packet_get_field(p, FLX_DNS_FIELD_ANCOUNT) == 0 ||
344 flx_dns_packet_get_field(p, FLX_DNS_FIELD_NSCOUNT) != 0) {
345 g_warning("Invalid response packet.");
349 handle_response(s, p, i, &a);
350 g_message("Handled response");
354 static void work(flxServer *s) {
355 struct sockaddr_in6 sa6;
356 struct sockaddr_in sa;
363 if (s->pollfd_ipv4.revents & G_IO_IN) {
364 if ((p = flx_recv_dns_packet_ipv4(s->fd_ipv4, &sa, &iface, &ttl))) {
365 dispatch_packet(s, p, (struct sockaddr*) &sa, iface, ttl);
366 flx_dns_packet_free(p);
370 if (s->pollfd_ipv6.revents & G_IO_IN) {
371 if ((p = flx_recv_dns_packet_ipv6(s->fd_ipv6, &sa6, &iface, &ttl))) {
372 dispatch_packet(s, p, (struct sockaddr*) &sa6, iface, ttl);
373 flx_dns_packet_free(p);
378 static gboolean prepare_func(GSource *source, gint *timeout) {
386 static gboolean check_func(GSource *source) {
390 s = *((flxServer**) (((guint8*) source) + sizeof(GSource)));
393 return (s->pollfd_ipv4.revents | s->pollfd_ipv6.revents) & (G_IO_IN | G_IO_HUP | G_IO_ERR);
396 static gboolean dispatch_func(GSource *source, GSourceFunc callback, gpointer user_data) {
400 s = *((flxServer**) (((guint8*) source) + sizeof(GSource)));
409 static void add_default_entries(flxServer *s) {
411 struct utsname utsname;
418 /* Fill in HINFO rr */
419 r = flx_record_new_full(s->hostname, FLX_DNS_CLASS_IN, FLX_DNS_TYPE_HINFO);
421 r->data.hinfo.cpu = g_strdup(g_strup(utsname.machine));
422 r->data.hinfo.os = g_strdup(g_strup(utsname.sysname));
423 flx_server_add(s, NULL, 0, AF_UNSPEC, FLX_ENTRY_UNIQUE | FLX_ENTRY_NOANNOUNCE | FLX_ENTRY_NOPROBE, r);
426 /* Add localhost entries */
427 flx_address_parse("127.0.0.1", AF_INET, &a);
428 flx_server_add_address(s, NULL, 0, AF_UNSPEC, FLX_ENTRY_UNIQUE|FLX_ENTRY_NOPROBE|FLX_ENTRY_NOANNOUNCE, "localhost", &a);
430 flx_address_parse("::1", AF_INET6, &a);
431 flx_server_add_address(s, NULL, 0, AF_UNSPEC, FLX_ENTRY_UNIQUE|FLX_ENTRY_NOPROBE|FLX_ENTRY_NOANNOUNCE, "ip6-localhost", &a);
434 flxServer *flx_server_new(GMainContext *c) {
438 static GSourceFuncs source_funcs = {
447 s = g_new(flxServer, 1);
449 s->ignore_bad_ttl = FALSE;
450 s->need_entry_cleanup = s->need_group_cleanup = FALSE;
452 s->fd_ipv4 = flx_open_socket_ipv4();
453 s->fd_ipv6 = -1 /*flx_open_socket_ipv6() */;
455 if (s->fd_ipv6 < 0 && s->fd_ipv4 < 0) {
456 g_critical("Failed to create IP sockets.\n");
462 g_message("Failed to create IPv4 socket, proceeding in IPv6 only mode");
463 else if (s->fd_ipv6 < 0)
464 g_message("Failed to create IPv6 socket, proceeding in IPv4 only mode");
467 g_main_context_ref(s->context = c);
469 s->context = g_main_context_default();
471 FLX_LLIST_HEAD_INIT(flxEntry, s->entries);
472 s->entries_by_key = g_hash_table_new((GHashFunc) flx_key_hash, (GEqualFunc) flx_key_equal);
473 FLX_LLIST_HEAD_INIT(flxGroup, s->groups);
475 FLX_LLIST_HEAD_INIT(flxSubscription, s->subscriptions);
476 s->subscription_hashtable = g_hash_table_new((GHashFunc) flx_key_hash, (GEqualFunc) flx_key_equal);
479 hn = flx_get_host_name();
480 hn[strcspn(hn, ".")] = 0;
482 s->hostname = g_strdup_printf("%s.local.", hn);
485 s->time_event_queue = flx_time_event_queue_new(s->context, G_PRIORITY_DEFAULT+10); /* Slightly less priority than the FDs */
486 s->monitor = flx_interface_monitor_new(s);
487 flx_interface_monitor_sync(s->monitor);
488 add_default_entries(s);
490 /* Prepare IO source registration */
491 s->source = g_source_new(&source_funcs, sizeof(GSource) + sizeof(flxServer*));
492 *((flxServer**) (((guint8*) s->source) + sizeof(GSource))) = s;
494 memset(&s->pollfd_ipv4, 0, sizeof(s->pollfd_ipv4));
495 s->pollfd_ipv4.fd = s->fd_ipv4;
496 s->pollfd_ipv4.events = G_IO_IN|G_IO_ERR|G_IO_HUP;
497 g_source_add_poll(s->source, &s->pollfd_ipv4);
499 memset(&s->pollfd_ipv6, 0, sizeof(s->pollfd_ipv6));
500 s->pollfd_ipv6.fd = s->fd_ipv6;
501 s->pollfd_ipv6.events = G_IO_IN|G_IO_ERR|G_IO_HUP;
502 g_source_add_poll(s->source, &s->pollfd_ipv6);
504 g_source_attach(s->source, s->context);
509 void flx_server_free(flxServer* s) {
513 free_entry(s, s->entries);
515 flx_interface_monitor_free(s->monitor);
518 free_group(s, s->groups);
520 while (s->subscriptions)
521 flx_subscription_free(s->subscriptions);
522 g_hash_table_destroy(s->subscription_hashtable);
524 g_hash_table_destroy(s->entries_by_key);
526 flx_time_event_queue_free(s->time_event_queue);
535 g_source_destroy(s->source);
536 g_source_unref(s->source);
537 g_main_context_unref(s->context);
554 g_assert(r->key->type != FLX_DNS_TYPE_ANY);
556 e = g_new(flxEntry, 1);
558 e->record = flx_record_ref(r);
560 e->interface = interface;
561 e->protocol = protocol;
565 FLX_LLIST_HEAD_INIT(flxAnnouncement, e->announcements);
567 FLX_LLIST_PREPEND(flxEntry, entries, s->entries, e);
569 /* Insert into hash table indexed by name */
570 t = g_hash_table_lookup(s->entries_by_key, e->record->key);
571 FLX_LLIST_PREPEND(flxEntry, by_key, t, e);
572 g_hash_table_replace(s->entries_by_key, e->record->key, t);
574 /* Insert into group list */
576 FLX_LLIST_PREPEND(flxEntry, by_group, g->entries, e);
578 flx_announce_entry(s, e);
580 const flxRecord *flx_server_iterate(flxServer *s, flxEntryGroup *g, void **state) {
581 flxEntry **e = (flxEntry**) state;
586 *e = g ? g->entries : s->entries;
588 while (*e && (*e)->dead)
589 *e = g ? (*e)->by_group_next : (*e)->entries_next;
594 return flx_record_ref((*e)->record);
597 void flx_server_dump(flxServer *s, FILE *f) {
602 fprintf(f, "\n;;; ZONE DUMP FOLLOWS ;;;\n");
604 for (e = s->entries; e; e = e->entries_next) {
610 t = flx_record_to_string(e->record);
611 fprintf(f, "%s ; iface=%i proto=%i\n", t, e->interface, e->protocol);
615 flx_dump_caches(s->monitor, f);
618 void flx_server_add_ptr(
631 r = flx_record_new_full(name ? name : s->hostname, FLX_DNS_CLASS_IN, FLX_DNS_TYPE_PTR);
632 r->data.ptr.name = flx_normalize_name(dest);
633 flx_server_add(s, g, interface, protocol, flags, r);
637 void flx_server_add_address(
650 name = name ? (n = flx_normalize_name(name)) : s->hostname;
652 if (a->family == AF_INET) {
656 r = flx_record_new_full(name, FLX_DNS_CLASS_IN, FLX_DNS_TYPE_A);
657 r->data.a.address = a->data.ipv4;
658 flx_server_add(s, g, interface, protocol, flags, r);
661 reverse = flx_reverse_lookup_name_ipv4(&a->data.ipv4);
663 flx_server_add_ptr(s, g, interface, protocol, flags, reverse, name);
670 r = flx_record_new_full(name, FLX_DNS_CLASS_IN, FLX_DNS_TYPE_AAAA);
671 r->data.aaaa.address = a->data.ipv6;
672 flx_server_add(s, g, interface, protocol, flags, r);
675 reverse = flx_reverse_lookup_name_ipv6_arpa(&a->data.ipv6);
677 flx_server_add_ptr(s, g, interface, protocol, flags, reverse, name);
680 reverse = flx_reverse_lookup_name_ipv6_int(&a->data.ipv6);
682 flx_server_add_ptr(s, g, interface, protocol, flags, reverse, name);
689 void flx_server_add_text_va(
702 r = flx_record_new_full(name ? name : s->hostname, FLX_DNS_CLASS_IN, FLX_DNS_TYPE_TXT);
703 r->data.txt.string_list = flx_string_list_new_va(va);
704 flx_server_add(s, g, interface, protocol, flags, r);
708 void flx_server_add_text(
722 flx_server_add_text_va(s, g, interface, protocol, flags, name, va);
726 static void escape_service_name(gchar *d, guint size, const gchar *s) {
731 while (*s && size >= 2) {
732 if (*s == '.' || *s == '\\') {
749 void flx_server_add_service_va(
761 gchar ptr_name[256], svc_name[256], ename[64], enum_ptr[256];
768 escape_service_name(ename, sizeof(ename), name);
771 while (domain[0] == '.')
779 snprintf(ptr_name, sizeof(ptr_name), "%s.%s", type, domain);
780 snprintf(svc_name, sizeof(svc_name), "%s.%s.%s", ename, type, domain);
782 flx_server_add_ptr(s, g, interface, protocol, FALSE, ptr_name, svc_name);
784 r = flx_record_new_full(svc_name, FLX_DNS_CLASS_IN, FLX_DNS_TYPE_SRV);
785 r->data.srv.priority = 0;
786 r->data.srv.weight = 0;
787 r->data.srv.port = port;
788 r->data.srv.name = flx_normalize_name(host);
789 flx_server_add(s, g, interface, protocol, TRUE, r);
792 flx_server_add_text_va(s, g, interface, protocol, FALSE, svc_name, va);
794 snprintf(enum_ptr, sizeof(enum_ptr), "_services._dns-sd._udp.%s", domain);
795 flx_server_add_ptr(s, g, interface, protocol, FALSE, enum_ptr, ptr_name);
798 void flx_server_add_service(
817 flx_server_add_service_va(s, g, interface, protocol, type, name, domain, host, port, va);
821 static void post_query_callback(flxInterfaceMonitor *m, flxInterface *i, gpointer userdata) {
822 flxKey *k = userdata;
828 flx_interface_post_query(i, k, FALSE);
831 void flx_server_post_query(flxServer *s, gint interface, guchar protocol, flxKey *key) {
835 flx_interface_monitor_walk(s->monitor, interface, protocol, post_query_callback, key);
840 gboolean flush_cache;
843 static void post_response_callback(flxInterfaceMonitor *m, flxInterface *i, gpointer userdata) {
844 struct tmpdata *tmpdata = userdata;
850 flx_interface_post_response(i, NULL, tmpdata->record, tmpdata->flush_cache, FALSE);
853 void flx_server_post_response(flxServer *s, gint interface, guchar protocol, flxRecord *record, gboolean flush_cache) {
854 struct tmpdata tmpdata;
859 tmpdata.record = record;
860 tmpdata.flush_cache = flush_cache;
862 flx_interface_monitor_walk(s->monitor, interface, protocol, post_response_callback, &tmpdata);
865 void flx_entry_group_run_callback(flxEntryGroup *g, flxEntryGroupStatus status) {
869 g->callback(g->server, g, status, g->userdata);
873 if (status == FLX_ENTRY_GROUP_COLLISION)
874 flx_entry_group_free(g);
876 /* Ignore the rest */
879 flxEntryGroup *flx_entry_group_new(flxServer *s, flxEntryGroupCallback callback, gpointer userdata) {
884 g = g_new(flxEntryGroup, 1);
886 g->callback = callback;
887 g->userdata = userdata;
889 g->status = FLX_ENTRY_GROUP_UNCOMMITED;
891 FLX_LLIST_HEAD_INIT(flxEntry, g->entries);
893 FLX_LLIST_PREPEND(flxEntryGroup, groups, s->groups, g);
897 void flx_entry_group_free(flxEntryGroup *g) {
902 g->server->need_group_cleanup = TRUE;
905 void flx_entry_group_commit(flxEntryGroup *g) {
911 if (g->status != FLX_ENTRY_GROUP_UNCOMMITED)
914 flx_entry_group_run_callback(g, g->status = FLX_ENTRY_GROUP_REGISTERING);
915 flx_announce_group(g->server, g);
916 flx_entry_group_check_probed(g, FALSE);
919 gboolean flx_entry_commited(flxEntry *e) {
924 e->group->status == FLX_ENTRY_GROUP_REGISTERING ||
925 e->group->status == FLX_ENTRY_GROUP_ESTABLISHED;
928 flxEntryGroupStatus flx_entry_group_get_status(flxEntryGroup *g) {