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) {
277 g_message("Handling response: %s", txt = flx_record_to_string(record));
280 if (handle_conflict(s, i, record, a)) {
281 flx_cache_update(i->cache, record, cache_flush, a);
282 flx_packet_scheduler_incoming_response(i->scheduler, record);
286 flx_record_unref(record);
290 static void dispatch_packet(flxServer *s, flxDnsPacket *p, struct sockaddr *sa, gint iface, gint ttl) {
299 g_message("new packet recieved.");
301 if (!(i = flx_interface_monitor_get_interface(s->monitor, iface, sa->sa_family))) {
302 g_warning("Recieved packet from invalid interface.");
307 g_warning("Recieved packet with invalid TTL on interface '%s.%i'.", i->hardware->name, i->protocol);
308 if (!s->ignore_bad_ttl)
312 if (sa->sa_family == AF_INET6) {
313 static const unsigned char ipv4_in_ipv6[] = {
314 0x00, 0x00, 0x00, 0x00,
315 0x00, 0x00, 0x00, 0x00,
316 0xFF, 0xFF, 0xFF, 0xFF };
318 if (memcmp(((struct sockaddr_in6*) sa)->sin6_addr.s6_addr, ipv4_in_ipv6, sizeof(ipv4_in_ipv6)) == 0) {
320 /* This is an IPv4 address encapsulated in IPv6, so let's ignore it. */
325 if (flx_dns_packet_check_valid(p) < 0) {
326 g_warning("Recieved invalid packet.");
330 flx_address_from_sockaddr(sa, &a);
332 if (flx_dns_packet_is_query(p)) {
334 if (flx_dns_packet_get_field(p, FLX_DNS_FIELD_QDCOUNT) == 0 ||
335 flx_dns_packet_get_field(p, FLX_DNS_FIELD_ARCOUNT) != 0) {
336 g_warning("Invalid query packet.");
340 handle_query(s, p, i, &a);
341 g_message("Handled query");
343 if (flx_dns_packet_get_field(p, FLX_DNS_FIELD_QDCOUNT) != 0 ||
344 flx_dns_packet_get_field(p, FLX_DNS_FIELD_ANCOUNT) == 0 ||
345 flx_dns_packet_get_field(p, FLX_DNS_FIELD_NSCOUNT) != 0) {
346 g_warning("Invalid response packet.");
350 handle_response(s, p, i, &a);
351 g_message("Handled response");
355 static void work(flxServer *s) {
356 struct sockaddr_in6 sa6;
357 struct sockaddr_in sa;
364 if (s->pollfd_ipv4.revents & G_IO_IN) {
365 if ((p = flx_recv_dns_packet_ipv4(s->fd_ipv4, &sa, &iface, &ttl))) {
366 dispatch_packet(s, p, (struct sockaddr*) &sa, iface, ttl);
367 flx_dns_packet_free(p);
371 if (s->pollfd_ipv6.revents & G_IO_IN) {
372 if ((p = flx_recv_dns_packet_ipv6(s->fd_ipv6, &sa6, &iface, &ttl))) {
373 dispatch_packet(s, p, (struct sockaddr*) &sa6, iface, ttl);
374 flx_dns_packet_free(p);
379 static gboolean prepare_func(GSource *source, gint *timeout) {
387 static gboolean check_func(GSource *source) {
391 s = *((flxServer**) (((guint8*) source) + sizeof(GSource)));
394 return (s->pollfd_ipv4.revents | s->pollfd_ipv6.revents) & (G_IO_IN | G_IO_HUP | G_IO_ERR);
397 static gboolean dispatch_func(GSource *source, GSourceFunc callback, gpointer user_data) {
401 s = *((flxServer**) (((guint8*) source) + sizeof(GSource)));
410 static void add_default_entries(flxServer *s) {
412 struct utsname utsname;
419 /* Fill in HINFO rr */
420 r = flx_record_new_full(s->hostname, FLX_DNS_CLASS_IN, FLX_DNS_TYPE_HINFO);
422 r->data.hinfo.cpu = g_strdup(g_strup(utsname.machine));
423 r->data.hinfo.os = g_strdup(g_strup(utsname.sysname));
424 flx_server_add(s, NULL, 0, AF_UNSPEC, FLX_ENTRY_UNIQUE | FLX_ENTRY_NOANNOUNCE | FLX_ENTRY_NOPROBE, r);
427 /* Add localhost entries */
428 flx_address_parse("127.0.0.1", AF_INET, &a);
429 flx_server_add_address(s, NULL, 0, AF_UNSPEC, FLX_ENTRY_UNIQUE|FLX_ENTRY_NOPROBE|FLX_ENTRY_NOANNOUNCE, "localhost", &a);
431 flx_address_parse("::1", AF_INET6, &a);
432 flx_server_add_address(s, NULL, 0, AF_UNSPEC, FLX_ENTRY_UNIQUE|FLX_ENTRY_NOPROBE|FLX_ENTRY_NOANNOUNCE, "ip6-localhost", &a);
435 flxServer *flx_server_new(GMainContext *c) {
439 static GSourceFuncs source_funcs = {
448 s = g_new(flxServer, 1);
450 s->ignore_bad_ttl = FALSE;
451 s->need_entry_cleanup = s->need_group_cleanup = FALSE;
453 s->fd_ipv4 = flx_open_socket_ipv4();
454 s->fd_ipv6 = -1 /*flx_open_socket_ipv6() */;
456 if (s->fd_ipv6 < 0 && s->fd_ipv4 < 0) {
457 g_critical("Failed to create IP sockets.\n");
463 g_message("Failed to create IPv4 socket, proceeding in IPv6 only mode");
464 else if (s->fd_ipv6 < 0)
465 g_message("Failed to create IPv6 socket, proceeding in IPv4 only mode");
468 g_main_context_ref(s->context = c);
470 s->context = g_main_context_default();
472 FLX_LLIST_HEAD_INIT(flxEntry, s->entries);
473 s->entries_by_key = g_hash_table_new((GHashFunc) flx_key_hash, (GEqualFunc) flx_key_equal);
474 FLX_LLIST_HEAD_INIT(flxGroup, s->groups);
476 FLX_LLIST_HEAD_INIT(flxSubscription, s->subscriptions);
477 s->subscription_hashtable = g_hash_table_new((GHashFunc) flx_key_hash, (GEqualFunc) flx_key_equal);
480 hn = flx_get_host_name();
481 hn[strcspn(hn, ".")] = 0;
483 s->hostname = g_strdup_printf("%s.local.", hn);
486 s->time_event_queue = flx_time_event_queue_new(s->context, G_PRIORITY_DEFAULT+10); /* Slightly less priority than the FDs */
487 s->monitor = flx_interface_monitor_new(s);
488 flx_interface_monitor_sync(s->monitor);
489 add_default_entries(s);
491 /* Prepare IO source registration */
492 s->source = g_source_new(&source_funcs, sizeof(GSource) + sizeof(flxServer*));
493 *((flxServer**) (((guint8*) s->source) + sizeof(GSource))) = s;
495 memset(&s->pollfd_ipv4, 0, sizeof(s->pollfd_ipv4));
496 s->pollfd_ipv4.fd = s->fd_ipv4;
497 s->pollfd_ipv4.events = G_IO_IN|G_IO_ERR|G_IO_HUP;
498 g_source_add_poll(s->source, &s->pollfd_ipv4);
500 memset(&s->pollfd_ipv6, 0, sizeof(s->pollfd_ipv6));
501 s->pollfd_ipv6.fd = s->fd_ipv6;
502 s->pollfd_ipv6.events = G_IO_IN|G_IO_ERR|G_IO_HUP;
503 g_source_add_poll(s->source, &s->pollfd_ipv6);
505 g_source_attach(s->source, s->context);
510 void flx_server_free(flxServer* s) {
514 free_entry(s, s->entries);
516 flx_interface_monitor_free(s->monitor);
519 free_group(s, s->groups);
521 while (s->subscriptions)
522 flx_subscription_free(s->subscriptions);
523 g_hash_table_destroy(s->subscription_hashtable);
525 g_hash_table_destroy(s->entries_by_key);
527 flx_time_event_queue_free(s->time_event_queue);
536 g_source_destroy(s->source);
537 g_source_unref(s->source);
538 g_main_context_unref(s->context);
555 g_assert(r->key->type != FLX_DNS_TYPE_ANY);
557 e = g_new(flxEntry, 1);
559 e->record = flx_record_ref(r);
561 e->interface = interface;
562 e->protocol = protocol;
566 FLX_LLIST_HEAD_INIT(flxAnnouncement, e->announcements);
568 FLX_LLIST_PREPEND(flxEntry, entries, s->entries, e);
570 /* Insert into hash table indexed by name */
571 t = g_hash_table_lookup(s->entries_by_key, e->record->key);
572 FLX_LLIST_PREPEND(flxEntry, by_key, t, e);
573 g_hash_table_replace(s->entries_by_key, e->record->key, t);
575 /* Insert into group list */
577 FLX_LLIST_PREPEND(flxEntry, by_group, g->entries, e);
579 flx_announce_entry(s, e);
581 const flxRecord *flx_server_iterate(flxServer *s, flxEntryGroup *g, void **state) {
582 flxEntry **e = (flxEntry**) state;
587 *e = g ? g->entries : s->entries;
589 while (*e && (*e)->dead)
590 *e = g ? (*e)->by_group_next : (*e)->entries_next;
595 return flx_record_ref((*e)->record);
598 void flx_server_dump(flxServer *s, FILE *f) {
603 fprintf(f, "\n;;; ZONE DUMP FOLLOWS ;;;\n");
605 for (e = s->entries; e; e = e->entries_next) {
611 t = flx_record_to_string(e->record);
612 fprintf(f, "%s ; iface=%i proto=%i\n", t, e->interface, e->protocol);
616 flx_dump_caches(s->monitor, f);
619 void flx_server_add_ptr(
632 r = flx_record_new_full(name ? name : s->hostname, FLX_DNS_CLASS_IN, FLX_DNS_TYPE_PTR);
633 r->data.ptr.name = flx_normalize_name(dest);
634 flx_server_add(s, g, interface, protocol, flags, r);
638 void flx_server_add_address(
651 name = name ? (n = flx_normalize_name(name)) : s->hostname;
653 if (a->family == AF_INET) {
657 r = flx_record_new_full(name, FLX_DNS_CLASS_IN, FLX_DNS_TYPE_A);
658 r->data.a.address = a->data.ipv4;
659 flx_server_add(s, g, interface, protocol, flags, r);
662 reverse = flx_reverse_lookup_name_ipv4(&a->data.ipv4);
664 flx_server_add_ptr(s, g, interface, protocol, flags, reverse, name);
671 r = flx_record_new_full(name, FLX_DNS_CLASS_IN, FLX_DNS_TYPE_AAAA);
672 r->data.aaaa.address = a->data.ipv6;
673 flx_server_add(s, g, interface, protocol, flags, r);
676 reverse = flx_reverse_lookup_name_ipv6_arpa(&a->data.ipv6);
678 flx_server_add_ptr(s, g, interface, protocol, flags, reverse, name);
681 reverse = flx_reverse_lookup_name_ipv6_int(&a->data.ipv6);
683 flx_server_add_ptr(s, g, interface, protocol, flags, reverse, name);
690 void flx_server_add_text_va(
703 r = flx_record_new_full(name ? name : s->hostname, FLX_DNS_CLASS_IN, FLX_DNS_TYPE_TXT);
704 r->data.txt.string_list = flx_string_list_new_va(va);
705 flx_server_add(s, g, interface, protocol, flags, r);
709 void flx_server_add_text(
723 flx_server_add_text_va(s, g, interface, protocol, flags, name, va);
727 static void escape_service_name(gchar *d, guint size, const gchar *s) {
732 while (*s && size >= 2) {
733 if (*s == '.' || *s == '\\') {
750 void flx_server_add_service_va(
762 gchar ptr_name[256], svc_name[256], ename[64], enum_ptr[256];
769 escape_service_name(ename, sizeof(ename), name);
772 while (domain[0] == '.')
780 snprintf(ptr_name, sizeof(ptr_name), "%s.%s", type, domain);
781 snprintf(svc_name, sizeof(svc_name), "%s.%s.%s", ename, type, domain);
783 flx_server_add_ptr(s, g, interface, protocol, FALSE, ptr_name, svc_name);
785 r = flx_record_new_full(svc_name, FLX_DNS_CLASS_IN, FLX_DNS_TYPE_SRV);
786 r->data.srv.priority = 0;
787 r->data.srv.weight = 0;
788 r->data.srv.port = port;
789 r->data.srv.name = flx_normalize_name(host);
790 flx_server_add(s, g, interface, protocol, TRUE, r);
793 flx_server_add_text_va(s, g, interface, protocol, FALSE, svc_name, va);
795 snprintf(enum_ptr, sizeof(enum_ptr), "_services._dns-sd._udp.%s", domain);
796 flx_server_add_ptr(s, g, interface, protocol, FALSE, enum_ptr, ptr_name);
799 void flx_server_add_service(
818 flx_server_add_service_va(s, g, interface, protocol, type, name, domain, host, port, va);
822 static void post_query_callback(flxInterfaceMonitor *m, flxInterface *i, gpointer userdata) {
823 flxKey *k = userdata;
829 flx_interface_post_query(i, k, FALSE);
832 void flx_server_post_query(flxServer *s, gint interface, guchar protocol, flxKey *key) {
836 flx_interface_monitor_walk(s->monitor, interface, protocol, post_query_callback, key);
841 gboolean flush_cache;
844 static void post_response_callback(flxInterfaceMonitor *m, flxInterface *i, gpointer userdata) {
845 struct tmpdata *tmpdata = userdata;
851 flx_interface_post_response(i, NULL, tmpdata->record, tmpdata->flush_cache, FALSE);
854 void flx_server_post_response(flxServer *s, gint interface, guchar protocol, flxRecord *record, gboolean flush_cache) {
855 struct tmpdata tmpdata;
860 tmpdata.record = record;
861 tmpdata.flush_cache = flush_cache;
863 flx_interface_monitor_walk(s->monitor, interface, protocol, post_response_callback, &tmpdata);
866 void flx_entry_group_run_callback(flxEntryGroup *g, flxEntryGroupStatus status) {
870 g->callback(g->server, g, status, g->userdata);
874 if (status == FLX_ENTRY_GROUP_COLLISION)
875 flx_entry_group_free(g);
877 /* Ignore the rest */
880 flxEntryGroup *flx_entry_group_new(flxServer *s, flxEntryGroupCallback callback, gpointer userdata) {
885 g = g_new(flxEntryGroup, 1);
887 g->callback = callback;
888 g->userdata = userdata;
890 g->status = FLX_ENTRY_GROUP_UNCOMMITED;
892 FLX_LLIST_HEAD_INIT(flxEntry, g->entries);
894 FLX_LLIST_PREPEND(flxEntryGroup, groups, s->groups, g);
898 void flx_entry_group_free(flxEntryGroup *g) {
903 g->server->need_group_cleanup = TRUE;
906 void flx_entry_group_commit(flxEntryGroup *g) {
912 if (g->status != FLX_ENTRY_GROUP_UNCOMMITED)
915 flx_entry_group_run_callback(g, g->status = FLX_ENTRY_GROUP_REGISTERING);
916 flx_announce_group(g->server, g);
917 flx_entry_group_check_probed(g, FALSE);
920 gboolean flx_entry_commited(flxEntry *e) {
925 e->group->status == FLX_ENTRY_GROUP_REGISTERING ||
926 e->group->status == FLX_ENTRY_GROUP_ESTABLISHED;
929 flxEntryGroupStatus flx_entry_group_get_status(flxEntryGroup *g) {