| /*** |
| This file is part of avahi. |
| |
| avahi is free software; you can redistribute it and/or modify it |
| under the terms of the GNU Lesser General Public License as |
| published by the Free Software Foundation; either version 2.1 of the |
| License, or (at your option) any later version. |
| |
| avahi is distributed in the hope that it will be useful, but WITHOUT |
| ANY WARRANTY; without even the implied warranty of MERCHANTABILITY |
| or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General |
| Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with avahi; if not, write to the Free Software |
| Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 |
| USA. |
| ***/ |
| |
| #ifdef HAVE_CONFIG_H |
| #include <config.h> |
| #endif |
| |
| #include <sys/types.h> |
| #include <sys/socket.h> |
| #include <netinet/in.h> |
| #include <arpa/inet.h> |
| #include <string.h> |
| #include <sys/utsname.h> |
| #include <unistd.h> |
| #include <errno.h> |
| #include <stdio.h> |
| #include <assert.h> |
| #include <stdlib.h> |
| |
| #include <avahi-common/domain.h> |
| #include <avahi-common/timeval.h> |
| #include <avahi-common/malloc.h> |
| #include <avahi-common/error.h> |
| |
| #include "internal.h" |
| #include "iface.h" |
| #include "socket.h" |
| #include "browse.h" |
| #include "log.h" |
| #include "util.h" |
| #include "dns-srv-rr.h" |
| #include "addr-util.h" |
| #include "domain-util.h" |
| #include "rr-util.h" |
| |
| #define AVAHI_DEFAULT_CACHE_ENTRIES_MAX 4096 |
| |
| static void enum_aux_records(AvahiServer *s, AvahiInterface *i, const char *name, uint16_t type, void (*callback)(AvahiServer *s, AvahiRecord *r, int flush_cache, void* userdata), void* userdata) { |
| assert(s); |
| assert(i); |
| assert(name); |
| assert(callback); |
| |
| if (type == AVAHI_DNS_TYPE_ANY) { |
| AvahiEntry *e; |
| |
| for (e = s->entries; e; e = e->entries_next) |
| if (!e->dead && |
| avahi_entry_is_registered(s, e, i) && |
| e->record->key->clazz == AVAHI_DNS_CLASS_IN && |
| avahi_domain_equal(name, e->record->key->name)) |
| callback(s, e->record, e->flags & AVAHI_PUBLISH_UNIQUE, userdata); |
| |
| } else { |
| AvahiEntry *e; |
| AvahiKey *k; |
| |
| if (!(k = avahi_key_new(name, AVAHI_DNS_CLASS_IN, type))) |
| return; /** OOM */ |
| |
| for (e = avahi_hashmap_lookup(s->entries_by_key, k); e; e = e->by_key_next) |
| if (!e->dead && avahi_entry_is_registered(s, e, i)) |
| callback(s, e->record, e->flags & AVAHI_PUBLISH_UNIQUE, userdata); |
| |
| avahi_key_unref(k); |
| } |
| } |
| |
| void avahi_server_enumerate_aux_records(AvahiServer *s, AvahiInterface *i, AvahiRecord *r, void (*callback)(AvahiServer *s, AvahiRecord *r, int flush_cache, void* userdata), void* userdata) { |
| assert(s); |
| assert(i); |
| assert(r); |
| assert(callback); |
| |
| /* Call the specified callback far all records referenced by the one specified in *r */ |
| |
| if (r->key->clazz == AVAHI_DNS_CLASS_IN) { |
| if (r->key->type == AVAHI_DNS_TYPE_PTR) { |
| enum_aux_records(s, i, r->data.ptr.name, AVAHI_DNS_TYPE_SRV, callback, userdata); |
| enum_aux_records(s, i, r->data.ptr.name, AVAHI_DNS_TYPE_TXT, callback, userdata); |
| } else if (r->key->type == AVAHI_DNS_TYPE_SRV) { |
| enum_aux_records(s, i, r->data.srv.name, AVAHI_DNS_TYPE_A, callback, userdata); |
| enum_aux_records(s, i, r->data.srv.name, AVAHI_DNS_TYPE_AAAA, callback, userdata); |
| } else if (r->key->type == AVAHI_DNS_TYPE_CNAME) |
| enum_aux_records(s, i, r->data.cname.name, AVAHI_DNS_TYPE_ANY, callback, userdata); |
| } |
| } |
| |
| void avahi_server_prepare_response(AvahiServer *s, AvahiInterface *i, AvahiEntry *e, int unicast_response, int auxiliary) { |
| assert(s); |
| assert(i); |
| assert(e); |
| |
| avahi_record_list_push(s->record_list, e->record, e->flags & AVAHI_PUBLISH_UNIQUE, unicast_response, auxiliary); |
| } |
| |
| void avahi_server_prepare_matching_responses(AvahiServer *s, AvahiInterface *i, AvahiKey *k, int unicast_response) { |
| assert(s); |
| assert(i); |
| assert(k); |
| |
| /* Push all records that match the specified key to the record list */ |
| |
| if (avahi_key_is_pattern(k)) { |
| AvahiEntry *e; |
| |
| /* Handle ANY query */ |
| |
| for (e = s->entries; e; e = e->entries_next) |
| if (!e->dead && avahi_key_pattern_match(k, e->record->key) && avahi_entry_is_registered(s, e, i)) |
| avahi_server_prepare_response(s, i, e, unicast_response, 0); |
| |
| } else { |
| AvahiEntry *e; |
| |
| /* Handle all other queries */ |
| |
| for (e = avahi_hashmap_lookup(s->entries_by_key, k); e; e = e->by_key_next) |
| if (!e->dead && avahi_entry_is_registered(s, e, i)) |
| avahi_server_prepare_response(s, i, e, unicast_response, 0); |
| } |
| |
| /* Look for CNAME records */ |
| |
| if ((k->clazz == AVAHI_DNS_CLASS_IN || k->clazz == AVAHI_DNS_CLASS_ANY) |
| && k->type != AVAHI_DNS_TYPE_CNAME && k->type != AVAHI_DNS_TYPE_ANY) { |
| |
| AvahiKey *cname_key; |
| |
| if (!(cname_key = avahi_key_new(k->name, AVAHI_DNS_CLASS_IN, AVAHI_DNS_TYPE_CNAME))) |
| return; |
| |
| avahi_server_prepare_matching_responses(s, i, cname_key, unicast_response); |
| avahi_key_unref(cname_key); |
| } |
| } |
| |
| static void withdraw_entry(AvahiServer *s, AvahiEntry *e) { |
| assert(s); |
| assert(e); |
| |
| /* Withdraw the specified entry, and if is part of an entry group, |
| * put that into COLLISION state */ |
| |
| if (e->dead) |
| return; |
| |
| if (e->group) { |
| AvahiEntry *k; |
| |
| for (k = e->group->entries; k; k = k->by_group_next) |
| if (!k->dead) { |
| avahi_goodbye_entry(s, k, 0, 1); |
| k->dead = 1; |
| } |
| |
| e->group->n_probing = 0; |
| |
| avahi_s_entry_group_change_state(e->group, AVAHI_ENTRY_GROUP_COLLISION); |
| } else { |
| avahi_goodbye_entry(s, e, 0, 1); |
| e->dead = 1; |
| } |
| |
| s->need_entry_cleanup = 1; |
| } |
| |
| static void withdraw_rrset(AvahiServer *s, AvahiKey *key) { |
| AvahiEntry *e; |
| |
| assert(s); |
| assert(key); |
| |
| /* Withdraw an entry RRSset */ |
| |
| for (e = avahi_hashmap_lookup(s->entries_by_key, key); e; e = e->by_key_next) |
| withdraw_entry(s, e); |
| } |
| |
| static void incoming_probe(AvahiServer *s, AvahiRecord *record, AvahiInterface *i) { |
| AvahiEntry *e, *n; |
| int ours = 0, won = 0, lost = 0; |
| |
| assert(s); |
| assert(record); |
| assert(i); |
| |
| /* Handle incoming probes and check if they conflict our own probes */ |
| |
| for (e = avahi_hashmap_lookup(s->entries_by_key, record->key); e; e = n) { |
| int cmp; |
| n = e->by_key_next; |
| |
| if (e->dead) |
| continue; |
| |
| if ((cmp = avahi_record_lexicographical_compare(e->record, record)) == 0) { |
| ours = 1; |
| break; |
| } else { |
| |
| if (avahi_entry_is_probing(s, e, i)) { |
| if (cmp > 0) |
| won = 1; |
| else /* cmp < 0 */ |
| lost = 1; |
| } |
| } |
| } |
| |
| if (!ours) { |
| char *t = avahi_record_to_string(record); |
| |
| if (won) |
| avahi_log_debug("Received conflicting probe [%s]. Local host won.", t); |
| else if (lost) { |
| avahi_log_debug("Received conflicting probe [%s]. Local host lost. Withdrawing.", t); |
| withdraw_rrset(s, record->key); |
| } |
| |
| avahi_free(t); |
| } |
| } |
| |
| static int handle_conflict(AvahiServer *s, AvahiInterface *i, AvahiRecord *record, int unique) { |
| int valid = 1, ours = 0, conflict = 0, withdraw_immediately = 0; |
| AvahiEntry *e, *n, *conflicting_entry = NULL; |
| |
| assert(s); |
| assert(i); |
| assert(record); |
| |
| /* Check whether an incoming record conflicts with one of our own */ |
| |
| for (e = avahi_hashmap_lookup(s->entries_by_key, record->key); e; e = n) { |
| n = e->by_key_next; |
| |
| if (e->dead) |
| continue; |
| |
| /* Check if the incoming is a goodbye record */ |
| if (avahi_record_is_goodbye(record)) { |
| |
| if (avahi_record_equal_no_ttl(e->record, record)) { |
| char *t; |
| |
| /* Refresh */ |
| t = avahi_record_to_string(record); |
| avahi_log_debug("Received goodbye record for one of our records [%s]. Refreshing.", t); |
| avahi_server_prepare_matching_responses(s, i, e->record->key, 0); |
| |
| valid = 0; |
| avahi_free(t); |
| break; |
| } |
| |
| /* If the goodybe packet doesn't match one of our own RRs, we simply ignore it. */ |
| continue; |
| } |
| |
| if (!(e->flags & AVAHI_PUBLISH_UNIQUE) && !unique) |
| continue; |
| |
| /* Either our entry or the other is intended to be unique, so let's check */ |
| |
| if (avahi_record_equal_no_ttl(e->record, record)) { |
| ours = 1; /* We have an identical record, so this is no conflict */ |
| |
| /* Check wheter there is a TTL conflict */ |
| if (record->ttl <= e->record->ttl/2 && |
| avahi_entry_is_registered(s, e, i)) { |
| char *t; |
| /* Refresh */ |
| t = avahi_record_to_string(record); |
| |
| avahi_log_debug("Received record with bad TTL [%s]. Refreshing.", t); |
| avahi_server_prepare_matching_responses(s, i, e->record->key, 0); |
| valid = 0; |
| |
| avahi_free(t); |
| } |
| |
| /* There's no need to check the other entries of this RRset */ |
| break; |
| |
| } else { |
| |
| if (avahi_entry_is_registered(s, e, i)) { |
| |
| /* A conflict => we have to return to probe mode */ |
| conflict = 1; |
| conflicting_entry = e; |
| |
| } else if (avahi_entry_is_probing(s, e, i)) { |
| |
| /* We are currently registering a matching record, but |
| * someone else already claimed it, so let's |
| * withdraw */ |
| conflict = 1; |
| withdraw_immediately = 1; |
| } |
| } |
| } |
| |
| if (!ours && conflict) { |
| char *t; |
| |
| valid = 0; |
| |
| t = avahi_record_to_string(record); |
| |
| if (withdraw_immediately) { |
| avahi_log_debug("Received conflicting record [%s] with local record to be. Withdrawing.", t); |
| withdraw_rrset(s, record->key); |
| } else { |
| assert(conflicting_entry); |
| avahi_log_debug("Received conflicting record [%s]. Resetting our record.", t); |
| avahi_entry_return_to_initial_state(s, conflicting_entry, i); |
| |
| /* Local unique records are returned to probing |
| * state. Local shared records are reannounced. */ |
| } |
| |
| avahi_free(t); |
| } |
| |
| return valid; |
| } |
| |
| static void append_aux_callback(AvahiServer *s, AvahiRecord *r, int flush_cache, void* userdata) { |
| int *unicast_response = userdata; |
| |
| assert(s); |
| assert(r); |
| assert(unicast_response); |
| |
| avahi_record_list_push(s->record_list, r, flush_cache, *unicast_response, 1); |
| } |
| |
| static void append_aux_records_to_list(AvahiServer *s, AvahiInterface *i, AvahiRecord *r, int unicast_response) { |
| assert(s); |
| assert(r); |
| |
| avahi_server_enumerate_aux_records(s, i, r, append_aux_callback, &unicast_response); |
| } |
| |
| void avahi_server_generate_response(AvahiServer *s, AvahiInterface *i, AvahiDnsPacket *p, const AvahiAddress *a, uint16_t port, int legacy_unicast, int immediately) { |
| |
| assert(s); |
| assert(i); |
| assert(!legacy_unicast || (a && port > 0 && p)); |
| |
| if (legacy_unicast) { |
| AvahiDnsPacket *reply; |
| AvahiRecord *r; |
| |
| if (!(reply = avahi_dns_packet_new_reply(p, 512 + AVAHI_DNS_PACKET_EXTRA_SIZE /* unicast DNS maximum packet size is 512 */ , 1, 1))) |
| return; /* OOM */ |
| |
| while ((r = avahi_record_list_next(s->record_list, NULL, NULL, NULL))) { |
| |
| append_aux_records_to_list(s, i, r, 0); |
| |
| if (avahi_dns_packet_append_record(reply, r, 0, 10)) |
| avahi_dns_packet_inc_field(reply, AVAHI_DNS_FIELD_ANCOUNT); |
| else { |
| char *t = avahi_record_to_string(r); |
| avahi_log_warn("Record [%s] not fitting in legacy unicast packet, dropping.", t); |
| avahi_free(t); |
| } |
| |
| avahi_record_unref(r); |
| } |
| |
| if (avahi_dns_packet_get_field(reply, AVAHI_DNS_FIELD_ANCOUNT) != 0) |
| avahi_interface_send_packet_unicast(i, reply, a, port); |
| |
| avahi_dns_packet_free(reply); |
| |
| } else { |
| int unicast_response, flush_cache, auxiliary; |
| AvahiDnsPacket *reply = NULL; |
| AvahiRecord *r; |
| |
| /* In case the query packet was truncated never respond |
| immediately, because known answer suppression records might be |
| contained in later packets */ |
| int tc = p && !!(avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_FLAGS) & AVAHI_DNS_FLAG_TC); |
| |
| while ((r = avahi_record_list_next(s->record_list, &flush_cache, &unicast_response, &auxiliary))) { |
| |
| int im = immediately; |
| |
| /* Only send the response immediately if it contains a |
| * unique entry AND it is not in reply to a truncated |
| * packet AND it is not an auxiliary record AND all other |
| * responses for this record are unique too. */ |
| |
| if (flush_cache && !tc && !auxiliary && avahi_record_list_all_flush_cache(s->record_list)) |
| im = 1; |
| |
| if (!avahi_interface_post_response(i, r, flush_cache, a, im) && unicast_response) { |
| |
| /* Due to some reasons the record has not been scheduled. |
| * The client requested an unicast response in that |
| * case. Therefore we prepare such a response */ |
| |
| append_aux_records_to_list(s, i, r, unicast_response); |
| |
| for (;;) { |
| |
| if (!reply) { |
| assert(p); |
| |
| if (!(reply = avahi_dns_packet_new_reply(p, i->hardware->mtu, 0, 0))) |
| break; /* OOM */ |
| } |
| |
| if (avahi_dns_packet_append_record(reply, r, flush_cache, 0)) { |
| |
| /* Appending this record succeeded, so incremeant |
| * the specific header field, and return to the caller */ |
| |
| avahi_dns_packet_inc_field(reply, AVAHI_DNS_FIELD_ANCOUNT); |
| break; |
| } |
| |
| if (avahi_dns_packet_get_field(reply, AVAHI_DNS_FIELD_ANCOUNT) == 0) { |
| size_t size; |
| |
| /* The record is too large for one packet, so create a larger packet */ |
| |
| avahi_dns_packet_free(reply); |
| size = avahi_record_get_estimate_size(r) + AVAHI_DNS_PACKET_HEADER_SIZE; |
| |
| if (!(reply = avahi_dns_packet_new_reply(p, size + AVAHI_DNS_PACKET_EXTRA_SIZE, 0, 1))) |
| break; /* OOM */ |
| |
| if (avahi_dns_packet_append_record(reply, r, flush_cache, 0)) { |
| |
| /* Appending this record succeeded, so incremeant |
| * the specific header field, and return to the caller */ |
| |
| avahi_dns_packet_inc_field(reply, AVAHI_DNS_FIELD_ANCOUNT); |
| break; |
| |
| } else { |
| |
| /* We completely fucked up, there's |
| * nothing we can do. The RR just doesn't |
| * fit in. Let's ignore it. */ |
| |
| char *t; |
| avahi_dns_packet_free(reply); |
| reply = NULL; |
| t = avahi_record_to_string(r); |
| avahi_log_warn("Record [%s] too large, doesn't fit in any packet!", t); |
| avahi_free(t); |
| break; |
| } |
| } |
| |
| /* Appending the record didn't succeeed, so let's send this packet, and create a new one */ |
| avahi_interface_send_packet_unicast(i, reply, a, port); |
| avahi_dns_packet_free(reply); |
| reply = NULL; |
| } |
| } |
| |
| avahi_record_unref(r); |
| } |
| |
| if (reply) { |
| if (avahi_dns_packet_get_field(reply, AVAHI_DNS_FIELD_ANCOUNT) != 0) |
| avahi_interface_send_packet_unicast(i, reply, a, port); |
| avahi_dns_packet_free(reply); |
| } |
| } |
| |
| avahi_record_list_flush(s->record_list); |
| } |
| |
| static void reflect_response(AvahiServer *s, AvahiInterface *i, AvahiRecord *r, int flush_cache) { |
| AvahiInterface *j; |
| |
| assert(s); |
| assert(i); |
| assert(r); |
| |
| if (!s->config.enable_reflector) |
| return; |
| |
| for (j = s->monitor->interfaces; j; j = j->interface_next) |
| if (j != i && (s->config.reflect_ipv || j->protocol == i->protocol)) |
| avahi_interface_post_response(j, r, flush_cache, NULL, 1); |
| } |
| |
| static void* reflect_cache_walk_callback(AvahiCache *c, AvahiKey *pattern, AvahiCacheEntry *e, void* userdata) { |
| AvahiServer *s = userdata; |
| AvahiRecord* r; |
| |
| assert(c); |
| assert(pattern); |
| assert(e); |
| assert(s); |
| |
| /* Don't reflect cache entry with ipv6 link-local addresses. */ |
| r = e->record; |
| if ((r->key->type == AVAHI_DNS_TYPE_AAAA) && |
| (r->data.aaaa.address.address[0] == 0xFE) && |
| (r->data.aaaa.address.address[1] == 0x80)) |
| return NULL; |
| |
| avahi_record_list_push(s->record_list, e->record, e->cache_flush, 0, 0); |
| return NULL; |
| } |
| |
| static void reflect_query(AvahiServer *s, AvahiInterface *i, AvahiKey *k) { |
| AvahiInterface *j; |
| |
| assert(s); |
| assert(i); |
| assert(k); |
| |
| if (!s->config.enable_reflector) |
| return; |
| |
| for (j = s->monitor->interfaces; j; j = j->interface_next) |
| if (j != i && (s->config.reflect_ipv || j->protocol == i->protocol)) { |
| /* Post the query to other networks */ |
| avahi_interface_post_query(j, k, 1, NULL); |
| |
| /* Reply from caches of other network. This is needed to |
| * "work around" known answer suppression. */ |
| |
| avahi_cache_walk(j->cache, k, reflect_cache_walk_callback, s); |
| } |
| } |
| |
| static void reflect_probe(AvahiServer *s, AvahiInterface *i, AvahiRecord *r) { |
| AvahiInterface *j; |
| |
| assert(s); |
| assert(i); |
| assert(r); |
| |
| if (!s->config.enable_reflector) |
| return; |
| |
| for (j = s->monitor->interfaces; j; j = j->interface_next) |
| if (j != i && (s->config.reflect_ipv || j->protocol == i->protocol)) |
| avahi_interface_post_probe(j, r, 1); |
| } |
| |
| static void handle_query_packet(AvahiServer *s, AvahiDnsPacket *p, AvahiInterface *i, const AvahiAddress *a, uint16_t port, int legacy_unicast, int from_local_iface) { |
| size_t n; |
| int is_probe; |
| |
| assert(s); |
| assert(p); |
| assert(i); |
| assert(a); |
| |
| assert(avahi_record_list_is_empty(s->record_list)); |
| |
| is_probe = avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_NSCOUNT) > 0; |
| |
| /* Handle the questions */ |
| for (n = avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_QDCOUNT); n > 0; n --) { |
| AvahiKey *key; |
| int unicast_response = 0; |
| |
| if (!(key = avahi_dns_packet_consume_key(p, &unicast_response))) { |
| avahi_log_warn(__FILE__": Packet too short or invalid while reading question key. (Maybe a UTF-8 problem?)"); |
| goto fail; |
| } |
| |
| if (!legacy_unicast && !from_local_iface) { |
| reflect_query(s, i, key); |
| if (!unicast_response) |
| avahi_cache_start_poof(i->cache, key, a); |
| } |
| |
| if (avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ANCOUNT) == 0 && |
| !(avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_FLAGS) & AVAHI_DNS_FLAG_TC)) |
| /* Allow our own queries to be suppressed by incoming |
| * queries only when they do not include known answers */ |
| avahi_query_scheduler_incoming(i->query_scheduler, key); |
| |
| avahi_server_prepare_matching_responses(s, i, key, unicast_response); |
| avahi_key_unref(key); |
| } |
| |
| if (!legacy_unicast) { |
| |
| /* Known Answer Suppression */ |
| for (n = avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ANCOUNT); n > 0; n --) { |
| AvahiRecord *record; |
| int unique = 0; |
| |
| if (!(record = avahi_dns_packet_consume_record(p, &unique))) { |
| avahi_log_warn(__FILE__": Packet too short or invalid while reading known answer record. (Maybe a UTF-8 problem?)"); |
| goto fail; |
| } |
| |
| avahi_response_scheduler_suppress(i->response_scheduler, record, a); |
| avahi_record_list_drop(s->record_list, record); |
| avahi_cache_stop_poof(i->cache, record, a); |
| |
| avahi_record_unref(record); |
| } |
| |
| /* Probe record */ |
| for (n = avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_NSCOUNT); n > 0; n --) { |
| AvahiRecord *record; |
| int unique = 0; |
| |
| if (!(record = avahi_dns_packet_consume_record(p, &unique))) { |
| avahi_log_warn(__FILE__": Packet too short or invalid while reading probe record. (Maybe a UTF-8 problem?)"); |
| goto fail; |
| } |
| |
| if (!avahi_key_is_pattern(record->key)) { |
| if (!from_local_iface) |
| reflect_probe(s, i, record); |
| incoming_probe(s, record, i); |
| } |
| |
| avahi_record_unref(record); |
| } |
| } |
| |
| if (!avahi_record_list_is_empty(s->record_list)) |
| avahi_server_generate_response(s, i, p, a, port, legacy_unicast, is_probe); |
| |
| return; |
| |
| fail: |
| avahi_record_list_flush(s->record_list); |
| } |
| |
| static void handle_response_packet(AvahiServer *s, AvahiDnsPacket *p, AvahiInterface *i, const AvahiAddress *a, int from_local_iface) { |
| unsigned n; |
| |
| assert(s); |
| assert(p); |
| assert(i); |
| assert(a); |
| |
| for (n = avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ANCOUNT) + |
| avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ARCOUNT); n > 0; n--) { |
| AvahiRecord *record; |
| int cache_flush = 0; |
| |
| if (!(record = avahi_dns_packet_consume_record(p, &cache_flush))) { |
| avahi_log_warn(__FILE__": Packet too short or invalid while reading response record. (Maybe a UTF-8 problem?)"); |
| break; |
| } |
| |
| if (!avahi_key_is_pattern(record->key)) { |
| |
| if (handle_conflict(s, i, record, cache_flush)) { |
| if (!from_local_iface && !avahi_record_is_link_local_address(record)) |
| reflect_response(s, i, record, cache_flush); |
| avahi_cache_update(i->cache, record, cache_flush, a); |
| avahi_response_scheduler_incoming(i->response_scheduler, record, cache_flush); |
| } |
| } |
| |
| avahi_record_unref(record); |
| } |
| |
| /* If the incoming response contained a conflicting record, some |
| records have been scheduled for sending. We need to flush them |
| here. */ |
| if (!avahi_record_list_is_empty(s->record_list)) |
| avahi_server_generate_response(s, i, NULL, NULL, 0, 0, 1); |
| } |
| |
| static AvahiLegacyUnicastReflectSlot* allocate_slot(AvahiServer *s) { |
| unsigned n, idx = (unsigned) -1; |
| AvahiLegacyUnicastReflectSlot *slot; |
| |
| assert(s); |
| |
| if (!s->legacy_unicast_reflect_slots) |
| s->legacy_unicast_reflect_slots = avahi_new0(AvahiLegacyUnicastReflectSlot*, AVAHI_LEGACY_UNICAST_REFLECT_SLOTS_MAX); |
| |
| for (n = 0; n < AVAHI_LEGACY_UNICAST_REFLECT_SLOTS_MAX; n++, s->legacy_unicast_reflect_id++) { |
| idx = s->legacy_unicast_reflect_id % AVAHI_LEGACY_UNICAST_REFLECT_SLOTS_MAX; |
| |
| if (!s->legacy_unicast_reflect_slots[idx]) |
| break; |
| } |
| |
| if (idx == (unsigned) -1 || s->legacy_unicast_reflect_slots[idx]) |
| return NULL; |
| |
| if (!(slot = avahi_new(AvahiLegacyUnicastReflectSlot, 1))) |
| return NULL; /* OOM */ |
| |
| s->legacy_unicast_reflect_slots[idx] = slot; |
| slot->id = s->legacy_unicast_reflect_id++; |
| slot->server = s; |
| |
| return slot; |
| } |
| |
| static void deallocate_slot(AvahiServer *s, AvahiLegacyUnicastReflectSlot *slot) { |
| unsigned idx; |
| |
| assert(s); |
| assert(slot); |
| |
| idx = slot->id % AVAHI_LEGACY_UNICAST_REFLECT_SLOTS_MAX; |
| |
| assert(s->legacy_unicast_reflect_slots[idx] == slot); |
| |
| avahi_time_event_free(slot->time_event); |
| |
| avahi_free(slot); |
| s->legacy_unicast_reflect_slots[idx] = NULL; |
| } |
| |
| static void free_slots(AvahiServer *s) { |
| unsigned idx; |
| assert(s); |
| |
| if (!s->legacy_unicast_reflect_slots) |
| return; |
| |
| for (idx = 0; idx < AVAHI_LEGACY_UNICAST_REFLECT_SLOTS_MAX; idx ++) |
| if (s->legacy_unicast_reflect_slots[idx]) |
| deallocate_slot(s, s->legacy_unicast_reflect_slots[idx]); |
| |
| avahi_free(s->legacy_unicast_reflect_slots); |
| s->legacy_unicast_reflect_slots = NULL; |
| } |
| |
| static AvahiLegacyUnicastReflectSlot* find_slot(AvahiServer *s, uint16_t id) { |
| unsigned idx; |
| |
| assert(s); |
| |
| if (!s->legacy_unicast_reflect_slots) |
| return NULL; |
| |
| idx = id % AVAHI_LEGACY_UNICAST_REFLECT_SLOTS_MAX; |
| |
| if (!s->legacy_unicast_reflect_slots[idx] || s->legacy_unicast_reflect_slots[idx]->id != id) |
| return NULL; |
| |
| return s->legacy_unicast_reflect_slots[idx]; |
| } |
| |
| static void legacy_unicast_reflect_slot_timeout(AvahiTimeEvent *e, void *userdata) { |
| AvahiLegacyUnicastReflectSlot *slot = userdata; |
| |
| assert(e); |
| assert(slot); |
| assert(slot->time_event == e); |
| |
| deallocate_slot(slot->server, slot); |
| } |
| |
| static void reflect_legacy_unicast_query_packet(AvahiServer *s, AvahiDnsPacket *p, AvahiInterface *i, const AvahiAddress *a, uint16_t port) { |
| AvahiLegacyUnicastReflectSlot *slot; |
| AvahiInterface *j; |
| |
| assert(s); |
| assert(p); |
| assert(i); |
| assert(a); |
| assert(port > 0); |
| assert(i->protocol == a->proto); |
| |
| if (!s->config.enable_reflector) |
| return; |
| |
| /* Reflecting legacy unicast queries is a little more complicated |
| than reflecting normal queries, since we must route the |
| responses back to the right client. Therefore we must store |
| some information for finding the right client contact data for |
| response packets. In contrast to normal queries legacy |
| unicast query and response packets are reflected untouched and |
| are not reassembled into larger packets */ |
| |
| if (!(slot = allocate_slot(s))) { |
| /* No slot available, we drop this legacy unicast query */ |
| avahi_log_warn("No slot available for legacy unicast reflection, dropping query packet."); |
| return; |
| } |
| |
| slot->original_id = avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ID); |
| slot->address = *a; |
| slot->port = port; |
| slot->interface = i->hardware->index; |
| |
| avahi_elapse_time(&slot->elapse_time, 2000, 0); |
| slot->time_event = avahi_time_event_new(s->time_event_queue, &slot->elapse_time, legacy_unicast_reflect_slot_timeout, slot); |
| |
| /* Patch the packet with our new locally generatet id */ |
| avahi_dns_packet_set_field(p, AVAHI_DNS_FIELD_ID, slot->id); |
| |
| for (j = s->monitor->interfaces; j; j = j->interface_next) |
| if (j->announcing && |
| j != i && |
| (s->config.reflect_ipv || j->protocol == i->protocol)) { |
| |
| if (j->protocol == AVAHI_PROTO_INET && s->fd_legacy_unicast_ipv4 >= 0) { |
| avahi_send_dns_packet_ipv4(s->fd_legacy_unicast_ipv4, j->hardware->index, p, NULL, NULL, 0); |
| } else if (j->protocol == AVAHI_PROTO_INET6 && s->fd_legacy_unicast_ipv6 >= 0) |
| avahi_send_dns_packet_ipv6(s->fd_legacy_unicast_ipv6, j->hardware->index, p, NULL, NULL, 0); |
| } |
| |
| /* Reset the id */ |
| avahi_dns_packet_set_field(p, AVAHI_DNS_FIELD_ID, slot->original_id); |
| } |
| |
| static int originates_from_local_legacy_unicast_socket(AvahiServer *s, const AvahiAddress *address, uint16_t port) { |
| assert(s); |
| assert(address); |
| assert(port > 0); |
| |
| if (!s->config.enable_reflector) |
| return 0; |
| |
| if (!avahi_address_is_local(s->monitor, address)) |
| return 0; |
| |
| if (address->proto == AVAHI_PROTO_INET && s->fd_legacy_unicast_ipv4 >= 0) { |
| struct sockaddr_in lsa; |
| socklen_t l = sizeof(lsa); |
| |
| if (getsockname(s->fd_legacy_unicast_ipv4, (struct sockaddr*) &lsa, &l) != 0) |
| avahi_log_warn("getsockname(): %s", strerror(errno)); |
| else |
| return avahi_port_from_sockaddr((struct sockaddr*) &lsa) == port; |
| |
| } |
| |
| if (address->proto == AVAHI_PROTO_INET6 && s->fd_legacy_unicast_ipv6 >= 0) { |
| struct sockaddr_in6 lsa; |
| socklen_t l = sizeof(lsa); |
| |
| if (getsockname(s->fd_legacy_unicast_ipv6, (struct sockaddr*) &lsa, &l) != 0) |
| avahi_log_warn("getsockname(): %s", strerror(errno)); |
| else |
| return avahi_port_from_sockaddr((struct sockaddr*) &lsa) == port; |
| } |
| |
| return 0; |
| } |
| |
| static int is_mdns_mcast_address(const AvahiAddress *a) { |
| AvahiAddress b; |
| assert(a); |
| |
| avahi_address_parse(a->proto == AVAHI_PROTO_INET ? AVAHI_IPV4_MCAST_GROUP : AVAHI_IPV6_MCAST_GROUP, a->proto, &b); |
| return avahi_address_cmp(a, &b) == 0; |
| } |
| |
| static int originates_from_local_iface(AvahiServer *s, AvahiIfIndex iface, const AvahiAddress *a, uint16_t port) { |
| assert(s); |
| assert(iface != AVAHI_IF_UNSPEC); |
| assert(a); |
| |
| /* If it isn't the MDNS port it can't be generated by us */ |
| if (port != AVAHI_MDNS_PORT) |
| return 0; |
| |
| return avahi_interface_has_address(s->monitor, iface, a); |
| } |
| |
| static void dispatch_packet(AvahiServer *s, AvahiDnsPacket *p, const AvahiAddress *src_address, uint16_t port, const AvahiAddress *dst_address, AvahiIfIndex iface, int ttl) { |
| AvahiInterface *i; |
| int from_local_iface = 0; |
| |
| assert(s); |
| assert(p); |
| assert(src_address); |
| assert(dst_address); |
| assert(iface > 0); |
| assert(src_address->proto == dst_address->proto); |
| |
| if (!(i = avahi_interface_monitor_get_interface(s->monitor, iface, src_address->proto)) || |
| !i->announcing) { |
| avahi_log_warn("Received packet from invalid interface."); |
| return; |
| } |
| |
| if (port <= 0) { |
| /* This fixes RHBZ #475394 */ |
| avahi_log_warn("Received packet from invalid source port %u.", (unsigned) port); |
| return; |
| } |
| |
| if (avahi_address_is_ipv4_in_ipv6(src_address)) |
| /* This is an IPv4 address encapsulated in IPv6, so let's ignore it. */ |
| return; |
| |
| if (originates_from_local_legacy_unicast_socket(s, src_address, port)) |
| /* This originates from our local reflector, so let's ignore it */ |
| return; |
| |
| /* We don't want to reflect local traffic, so we check if this packet is generated locally. */ |
| if (s->config.enable_reflector) |
| from_local_iface = originates_from_local_iface(s, iface, src_address, port); |
| |
| if (avahi_dns_packet_check_valid_multicast(p) < 0) { |
| avahi_log_warn("Received invalid packet."); |
| return; |
| } |
| |
| if (avahi_dns_packet_is_query(p)) { |
| int legacy_unicast = 0; |
| |
| /* For queries EDNS0 might allow ARCOUNT != 0. We ignore the |
| * AR section completely here, so far. Until the day we add |
| * EDNS0 support. */ |
| |
| if (port != AVAHI_MDNS_PORT) { |
| /* Legacy Unicast */ |
| |
| if ((avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ANCOUNT) != 0 || |
| avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_NSCOUNT) != 0)) { |
| avahi_log_warn("Invalid legacy unicast query packet."); |
| return; |
| } |
| |
| legacy_unicast = 1; |
| } |
| |
| if (legacy_unicast) |
| reflect_legacy_unicast_query_packet(s, p, i, src_address, port); |
| |
| handle_query_packet(s, p, i, src_address, port, legacy_unicast, from_local_iface); |
| |
| } else { |
| char t[AVAHI_ADDRESS_STR_MAX]; |
| |
| if (port != AVAHI_MDNS_PORT) { |
| avahi_log_warn("Received response from host %s with invalid source port %u on interface '%s.%i'", avahi_address_snprint(t, sizeof(t), src_address), port, i->hardware->name, i->protocol); |
| return; |
| } |
| |
| if (ttl != 255 && s->config.check_response_ttl) { |
| avahi_log_warn("Received response from host %s with invalid TTL %u on interface '%s.%i'.", avahi_address_snprint(t, sizeof(t), src_address), ttl, i->hardware->name, i->protocol); |
| return; |
| } |
| |
| if (!is_mdns_mcast_address(dst_address) && |
| !avahi_interface_address_on_link(i, src_address)) { |
| |
| avahi_log_warn("Received non-local response from host %s on interface '%s.%i'.", avahi_address_snprint(t, sizeof(t), src_address), i->hardware->name, i->protocol); |
| return; |
| } |
| |
| if (avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_QDCOUNT) != 0 || |
| avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ANCOUNT) == 0 || |
| avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_NSCOUNT) != 0) { |
| |
| avahi_log_warn("Invalid response packet from host %s.", avahi_address_snprint(t, sizeof(t), src_address)); |
| return; |
| } |
| |
| handle_response_packet(s, p, i, src_address, from_local_iface); |
| } |
| } |
| |
| static void dispatch_legacy_unicast_packet(AvahiServer *s, AvahiDnsPacket *p) { |
| AvahiInterface *j; |
| AvahiLegacyUnicastReflectSlot *slot; |
| |
| assert(s); |
| assert(p); |
| |
| if (avahi_dns_packet_check_valid(p) < 0 || avahi_dns_packet_is_query(p)) { |
| avahi_log_warn("Received invalid packet."); |
| return; |
| } |
| |
| if (!(slot = find_slot(s, avahi_dns_packet_get_field(p, AVAHI_DNS_FIELD_ID)))) { |
| avahi_log_warn("Received legacy unicast response with unknown id"); |
| return; |
| } |
| |
| if (!(j = avahi_interface_monitor_get_interface(s->monitor, slot->interface, slot->address.proto)) || |
| !j->announcing) |
| return; |
| |
| /* Patch the original ID into this response */ |
| avahi_dns_packet_set_field(p, AVAHI_DNS_FIELD_ID, slot->original_id); |
| |
| /* Forward the response to the correct client */ |
| avahi_interface_send_packet_unicast(j, p, &slot->address, slot->port); |
| |
| /* Undo changes to packet */ |
| avahi_dns_packet_set_field(p, AVAHI_DNS_FIELD_ID, slot->id); |
| } |
| |
| static void mcast_socket_event(AvahiWatch *w, int fd, AvahiWatchEvent events, void *userdata) { |
| AvahiServer *s = userdata; |
| AvahiAddress dest, src; |
| AvahiDnsPacket *p = NULL; |
| AvahiIfIndex iface; |
| uint16_t port; |
| uint8_t ttl; |
| |
| assert(w); |
| assert(fd >= 0); |
| assert(events & AVAHI_WATCH_IN); |
| |
| if (fd == s->fd_ipv4) { |
| dest.proto = src.proto = AVAHI_PROTO_INET; |
| p = avahi_recv_dns_packet_ipv4(s->fd_ipv4, &src.data.ipv4, &port, &dest.data.ipv4, &iface, &ttl); |
| } else { |
| assert(fd == s->fd_ipv6); |
| dest.proto = src.proto = AVAHI_PROTO_INET6; |
| p = avahi_recv_dns_packet_ipv6(s->fd_ipv6, &src.data.ipv6, &port, &dest.data.ipv6, &iface, &ttl); |
| } |
| |
| if (p) { |
| if (iface == AVAHI_IF_UNSPEC) |
| iface = avahi_find_interface_for_address(s->monitor, &dest); |
| |
| if (iface != AVAHI_IF_UNSPEC) |
| dispatch_packet(s, p, &src, port, &dest, iface, ttl); |
| else |
| avahi_log_error("Incoming packet received on address that isn't local."); |
| |
| avahi_dns_packet_free(p); |
| |
| avahi_cleanup_dead_entries(s); |
| } |
| } |
| |
| static void legacy_unicast_socket_event(AvahiWatch *w, int fd, AvahiWatchEvent events, void *userdata) { |
| AvahiServer *s = userdata; |
| AvahiDnsPacket *p = NULL; |
| |
| assert(w); |
| assert(fd >= 0); |
| assert(events & AVAHI_WATCH_IN); |
| |
| if (fd == s->fd_legacy_unicast_ipv4) |
| p = avahi_recv_dns_packet_ipv4(s->fd_legacy_unicast_ipv4, NULL, NULL, NULL, NULL, NULL); |
| else { |
| assert(fd == s->fd_legacy_unicast_ipv6); |
| p = avahi_recv_dns_packet_ipv6(s->fd_legacy_unicast_ipv6, NULL, NULL, NULL, NULL, NULL); |
| } |
| |
| if (p) { |
| dispatch_legacy_unicast_packet(s, p); |
| avahi_dns_packet_free(p); |
| |
| avahi_cleanup_dead_entries(s); |
| } |
| } |
| |
| static void server_set_state(AvahiServer *s, AvahiServerState state) { |
| assert(s); |
| |
| if (s->state == state) |
| return; |
| |
| s->state = state; |
| |
| avahi_interface_monitor_update_rrs(s->monitor, 0); |
| |
| if (s->callback) |
| s->callback(s, state, s->userdata); |
| } |
| |
| static void withdraw_host_rrs(AvahiServer *s) { |
| assert(s); |
| |
| if (s->hinfo_entry_group) |
| avahi_s_entry_group_reset(s->hinfo_entry_group); |
| |
| if (s->browse_domain_entry_group) |
| avahi_s_entry_group_reset(s->browse_domain_entry_group); |
| |
| avahi_interface_monitor_update_rrs(s->monitor, 1); |
| s->n_host_rr_pending = 0; |
| } |
| |
| void avahi_server_decrease_host_rr_pending(AvahiServer *s) { |
| assert(s); |
| |
| assert(s->n_host_rr_pending > 0); |
| |
| if (--s->n_host_rr_pending == 0) |
| server_set_state(s, AVAHI_SERVER_RUNNING); |
| } |
| |
| void avahi_host_rr_entry_group_callback(AvahiServer *s, AvahiSEntryGroup *g, AvahiEntryGroupState state, AVAHI_GCC_UNUSED void *userdata) { |
| assert(s); |
| assert(g); |
| |
| if (state == AVAHI_ENTRY_GROUP_REGISTERING && |
| s->state == AVAHI_SERVER_REGISTERING) |
| s->n_host_rr_pending ++; |
| |
| else if (state == AVAHI_ENTRY_GROUP_COLLISION && |
| (s->state == AVAHI_SERVER_REGISTERING || s->state == AVAHI_SERVER_RUNNING)) { |
| withdraw_host_rrs(s); |
| server_set_state(s, AVAHI_SERVER_COLLISION); |
| |
| } else if (state == AVAHI_ENTRY_GROUP_ESTABLISHED && |
| s->state == AVAHI_SERVER_REGISTERING) |
| avahi_server_decrease_host_rr_pending(s); |
| } |
| |
| static void register_hinfo(AvahiServer *s) { |
| struct utsname utsname; |
| AvahiRecord *r; |
| |
| assert(s); |
| |
| if (!s->config.publish_hinfo) |
| return; |
| |
| if (s->hinfo_entry_group) |
| assert(avahi_s_entry_group_is_empty(s->hinfo_entry_group)); |
| else |
| s->hinfo_entry_group = avahi_s_entry_group_new(s, avahi_host_rr_entry_group_callback, NULL); |
| |
| if (!s->hinfo_entry_group) { |
| avahi_log_warn("Failed to create HINFO entry group: %s", avahi_strerror(s->error)); |
| return; |
| } |
| |
| /* Fill in HINFO rr */ |
| if ((r = avahi_record_new_full(s->host_name_fqdn, AVAHI_DNS_CLASS_IN, AVAHI_DNS_TYPE_HINFO, AVAHI_DEFAULT_TTL_HOST_NAME))) { |
| |
| if (uname(&utsname) < 0) |
| avahi_log_warn("uname() failed: %s\n", avahi_strerror(errno)); |
| else { |
| |
| r->data.hinfo.cpu = avahi_strdup(avahi_strup(utsname.machine)); |
| r->data.hinfo.os = avahi_strdup(avahi_strup(utsname.sysname)); |
| |
| avahi_log_info("Registering HINFO record with values '%s'/'%s'.", r->data.hinfo.cpu, r->data.hinfo.os); |
| |
| if (avahi_server_add(s, s->hinfo_entry_group, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, AVAHI_PUBLISH_UNIQUE, r) < 0) { |
| avahi_log_warn("Failed to add HINFO RR: %s", avahi_strerror(s->error)); |
| return; |
| } |
| } |
| |
| avahi_record_unref(r); |
| } |
| |
| if (avahi_s_entry_group_commit(s->hinfo_entry_group) < 0) |
| avahi_log_warn("Failed to commit HINFO entry group: %s", avahi_strerror(s->error)); |
| |
| } |
| |
| static void register_localhost(AvahiServer *s) { |
| AvahiAddress a; |
| assert(s); |
| |
| /* Add localhost entries */ |
| avahi_address_parse("127.0.0.1", AVAHI_PROTO_INET, &a); |
| avahi_server_add_address(s, NULL, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, AVAHI_PUBLISH_NO_PROBE|AVAHI_PUBLISH_NO_ANNOUNCE, "localhost", &a); |
| |
| avahi_address_parse("::1", AVAHI_PROTO_INET6, &a); |
| avahi_server_add_address(s, NULL, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, AVAHI_PUBLISH_NO_PROBE|AVAHI_PUBLISH_NO_ANNOUNCE, "ip6-localhost", &a); |
| } |
| |
| static void register_browse_domain(AvahiServer *s) { |
| assert(s); |
| |
| if (!s->config.publish_domain) |
| return; |
| |
| if (avahi_domain_equal(s->domain_name, "local")) |
| return; |
| |
| if (s->browse_domain_entry_group) |
| assert(avahi_s_entry_group_is_empty(s->browse_domain_entry_group)); |
| else |
| s->browse_domain_entry_group = avahi_s_entry_group_new(s, NULL, NULL); |
| |
| if (!s->browse_domain_entry_group) { |
| avahi_log_warn("Failed to create browse domain entry group: %s", avahi_strerror(s->error)); |
| return; |
| } |
| |
| if (avahi_server_add_ptr(s, s->browse_domain_entry_group, AVAHI_IF_UNSPEC, AVAHI_PROTO_UNSPEC, 0, AVAHI_DEFAULT_TTL, "b._dns-sd._udp.local", s->domain_name) < 0) { |
| avahi_log_warn("Failed to add browse domain RR: %s", avahi_strerror(s->error)); |
| return; |
| } |
| |
| if (avahi_s_entry_group_commit(s->browse_domain_entry_group) < 0) |
| avahi_log_warn("Failed to commit browse domain entry group: %s", avahi_strerror(s->error)); |
| } |
| |
| static void register_stuff(AvahiServer *s) { |
| assert(s); |
| |
| server_set_state(s, AVAHI_SERVER_REGISTERING); |
| s->n_host_rr_pending ++; /** Make sure that the state isn't changed tp AVAHI_SERVER_RUNNING too early */ |
| |
| register_hinfo(s); |
| register_browse_domain(s); |
| avahi_interface_monitor_update_rrs(s->monitor, 0); |
| |
| assert(s->n_host_rr_pending > 0); |
| s->n_host_rr_pending --; |
| |
| if (s->n_host_rr_pending == 0) |
| server_set_state(s, AVAHI_SERVER_RUNNING); |
| } |
| |
| static void update_fqdn(AvahiServer *s) { |
| char *n; |
| |
| assert(s); |
| assert(s->host_name); |
| assert(s->domain_name); |
| |
| if (!(n = avahi_strdup_printf("%s.%s", s->host_name, s->domain_name))) |
| return; /* OOM */ |
| |
| avahi_free(s->host_name_fqdn); |
| s->host_name_fqdn = n; |
| } |
| |
| int avahi_server_set_host_name(AvahiServer *s, const char *host_name) { |
| char *hn = NULL; |
| assert(s); |
| |
| AVAHI_CHECK_VALIDITY(s, !host_name || avahi_is_valid_host_name(host_name), AVAHI_ERR_INVALID_HOST_NAME); |
| |
| if (!host_name) |
| hn = avahi_get_host_name_strdup(); |
| else |
| hn = avahi_normalize_name_strdup(host_name); |
| |
| hn[strcspn(hn, ".")] = 0; |
| |
| if (avahi_domain_equal(s->host_name, hn) && s->state != AVAHI_SERVER_COLLISION) { |
| avahi_free(hn); |
| return avahi_server_set_errno(s, AVAHI_ERR_NO_CHANGE); |
| } |
| |
| withdraw_host_rrs(s); |
| |
| avahi_free(s->host_name); |
| s->host_name = hn; |
| |
| update_fqdn(s); |
| |
| register_stuff(s); |
| return AVAHI_OK; |
| } |
| |
| int avahi_server_set_domain_name(AvahiServer *s, const char *domain_name) { |
| char *dn = NULL; |
| assert(s); |
| |
| AVAHI_CHECK_VALIDITY(s, !domain_name || avahi_is_valid_domain_name(domain_name), AVAHI_ERR_INVALID_DOMAIN_NAME); |
| |
| if (!domain_name) |
| dn = avahi_strdup("local"); |
| else |
| dn = avahi_normalize_name_strdup(domain_name); |
| |
| if (avahi_domain_equal(s->domain_name, domain_name)) { |
| avahi_free(dn); |
| return avahi_server_set_errno(s, AVAHI_ERR_NO_CHANGE); |
| } |
| |
| withdraw_host_rrs(s); |
| |
| avahi_free(s->domain_name); |
| s->domain_name = dn; |
| update_fqdn(s); |
| |
| register_stuff(s); |
| |
| avahi_free(dn); |
| return AVAHI_OK; |
| } |
| |
| static int valid_server_config(const AvahiServerConfig *sc) { |
| AvahiStringList *l; |
| |
| assert(sc); |
| |
| if (sc->n_wide_area_servers > AVAHI_WIDE_AREA_SERVERS_MAX) |
| return AVAHI_ERR_INVALID_CONFIG; |
| |
| if (sc->host_name && !avahi_is_valid_host_name(sc->host_name)) |
| return AVAHI_ERR_INVALID_HOST_NAME; |
| |
| if (sc->domain_name && !avahi_is_valid_domain_name(sc->domain_name)) |
| return AVAHI_ERR_INVALID_DOMAIN_NAME; |
| |
| for (l = sc->browse_domains; l; l = l->next) |
| if (!avahi_is_valid_domain_name((char*) l->text)) |
| return AVAHI_ERR_INVALID_DOMAIN_NAME; |
| |
| return AVAHI_OK; |
| } |
| |
| static int setup_sockets(AvahiServer *s) { |
| assert(s); |
| |
| s->fd_ipv4 = s->config.use_ipv4 ? avahi_open_socket_ipv4(s->config.disallow_other_stacks) : -1; |
| s->fd_ipv6 = s->config.use_ipv6 ? avahi_open_socket_ipv6(s->config.disallow_other_stacks) : -1; |
| |
| if (s->fd_ipv6 < 0 && s->fd_ipv4 < 0) |
| return AVAHI_ERR_NO_NETWORK; |
| |
| if (s->fd_ipv4 < 0 && s->config.use_ipv4) |
| avahi_log_notice("Failed to create IPv4 socket, proceeding in IPv6 only mode"); |
| else if (s->fd_ipv6 < 0 && s->config.use_ipv6) |
| avahi_log_notice("Failed to create IPv6 socket, proceeding in IPv4 only mode"); |
| |
| s->fd_legacy_unicast_ipv4 = s->fd_ipv4 >= 0 && s->config.enable_reflector ? avahi_open_unicast_socket_ipv4() : -1; |
| s->fd_legacy_unicast_ipv6 = s->fd_ipv6 >= 0 && s->config.enable_reflector ? avahi_open_unicast_socket_ipv6() : -1; |
| |
| s->watch_ipv4 = |
| s->watch_ipv6 = |
| s->watch_legacy_unicast_ipv4 = |
| s->watch_legacy_unicast_ipv6 = NULL; |
| |
| if (s->fd_ipv4 >= 0) |
| s->watch_ipv4 = s->poll_api->watch_new(s->poll_api, s->fd_ipv4, AVAHI_WATCH_IN, mcast_socket_event, s); |
| if (s->fd_ipv6 >= 0) |
| s->watch_ipv6 = s->poll_api->watch_new(s->poll_api, s->fd_ipv6, AVAHI_WATCH_IN, mcast_socket_event, s); |
| |
| if (s->fd_legacy_unicast_ipv4 >= 0) |
| s->watch_legacy_unicast_ipv4 = s->poll_api->watch_new(s->poll_api, s->fd_legacy_unicast_ipv4, AVAHI_WATCH_IN, legacy_unicast_socket_event, s); |
| if (s->fd_legacy_unicast_ipv6 >= 0) |
| s->watch_legacy_unicast_ipv6 = s->poll_api->watch_new(s->poll_api, s->fd_legacy_unicast_ipv6, AVAHI_WATCH_IN, legacy_unicast_socket_event, s); |
| |
| return 0; |
| } |
| |
| AvahiServer *avahi_server_new(const AvahiPoll *poll_api, const AvahiServerConfig *sc, AvahiServerCallback callback, void* userdata, int *error) { |
| AvahiServer *s; |
| int e; |
| |
| if (sc && (e = valid_server_config(sc)) < 0) { |
| if (error) |
| *error = e; |
| return NULL; |
| } |
| |
| if (!(s = avahi_new(AvahiServer, 1))) { |
| if (error) |
| *error = AVAHI_ERR_NO_MEMORY; |
| |
| return NULL; |
| } |
| |
| s->poll_api = poll_api; |
| |
| if (sc) |
| avahi_server_config_copy(&s->config, sc); |
| else |
| avahi_server_config_init(&s->config); |
| |
| if ((e = setup_sockets(s)) < 0) { |
| if (error) |
| *error = e; |
| |
| avahi_server_config_free(&s->config); |
| avahi_free(s); |
| |
| return NULL; |
| } |
| |
| s->n_host_rr_pending = 0; |
| s->need_entry_cleanup = 0; |
| s->need_group_cleanup = 0; |
| s->need_browser_cleanup = 0; |
| s->cleanup_time_event = NULL; |
| s->hinfo_entry_group = NULL; |
| s->browse_domain_entry_group = NULL; |
| s->error = AVAHI_OK; |
| s->state = AVAHI_SERVER_INVALID; |
| |
| s->callback = callback; |
| s->userdata = userdata; |
| |
| s->time_event_queue = avahi_time_event_queue_new(poll_api); |
| |
| s->entries_by_key = avahi_hashmap_new((AvahiHashFunc) avahi_key_hash, (AvahiEqualFunc) avahi_key_equal, NULL, NULL); |
| AVAHI_LLIST_HEAD_INIT(AvahiEntry, s->entries); |
| AVAHI_LLIST_HEAD_INIT(AvahiGroup, s->groups); |
| |
| s->record_browser_hashmap = avahi_hashmap_new((AvahiHashFunc) avahi_key_hash, (AvahiEqualFunc) avahi_key_equal, NULL, NULL); |
| AVAHI_LLIST_HEAD_INIT(AvahiSRecordBrowser, s->record_browsers); |
| AVAHI_LLIST_HEAD_INIT(AvahiSHostNameResolver, s->host_name_resolvers); |
| AVAHI_LLIST_HEAD_INIT(AvahiSAddressResolver, s->address_resolvers); |
| AVAHI_LLIST_HEAD_INIT(AvahiSDomainBrowser, s->domain_browsers); |
| AVAHI_LLIST_HEAD_INIT(AvahiSServiceTypeBrowser, s->service_type_browsers); |
| AVAHI_LLIST_HEAD_INIT(AvahiSServiceBrowser, s->service_browsers); |
| AVAHI_LLIST_HEAD_INIT(AvahiSServiceResolver, s->service_resolvers); |
| AVAHI_LLIST_HEAD_INIT(AvahiSDNSServerBrowser, s->dns_server_browsers); |
| |
| s->legacy_unicast_reflect_slots = NULL; |
| s->legacy_unicast_reflect_id = 0; |
| |
| s->record_list = avahi_record_list_new(); |
| |
| /* Get host name */ |
| s->host_name = s->config.host_name ? avahi_normalize_name_strdup(s->config.host_name) : avahi_get_host_name_strdup(); |
| s->host_name[strcspn(s->host_name, ".")] = 0; |
| s->domain_name = s->config.domain_name ? avahi_normalize_name_strdup(s->config.domain_name) : avahi_strdup("local"); |
| s->host_name_fqdn = NULL; |
| update_fqdn(s); |
| |
| do { |
| s->local_service_cookie = (uint32_t) rand() * (uint32_t) rand(); |
| } while (s->local_service_cookie == AVAHI_SERVICE_COOKIE_INVALID); |
| |
| if (s->config.enable_wide_area) { |
| s->wide_area_lookup_engine = avahi_wide_area_engine_new(s); |
| avahi_wide_area_set_servers(s->wide_area_lookup_engine, s->config.wide_area_servers, s->config.n_wide_area_servers); |
| } else |
| s->wide_area_lookup_engine = NULL; |
| |
| s->multicast_lookup_engine = avahi_multicast_lookup_engine_new(s); |
| |
| s->monitor = avahi_interface_monitor_new(s); |
| avahi_interface_monitor_sync(s->monitor); |
| |
| register_localhost(s); |
| register_stuff(s); |
| |
| return s; |
| } |
| |
| void avahi_server_free(AvahiServer* s) { |
| assert(s); |
| |
| /* Remove all browsers */ |
| |
| while (s->dns_server_browsers) |
| avahi_s_dns_server_browser_free(s->dns_server_browsers); |
| while (s->host_name_resolvers) |
| avahi_s_host_name_resolver_free(s->host_name_resolvers); |
| while (s->address_resolvers) |
| avahi_s_address_resolver_free(s->address_resolvers); |
| while (s->domain_browsers) |
| avahi_s_domain_browser_free(s->domain_browsers); |
| while (s->service_type_browsers) |
| avahi_s_service_type_browser_free(s->service_type_browsers); |
| while (s->service_browsers) |
| avahi_s_service_browser_free(s->service_browsers); |
| while (s->service_resolvers) |
| avahi_s_service_resolver_free(s->service_resolvers); |
| while (s->record_browsers) |
| avahi_s_record_browser_destroy(s->record_browsers); |
| |
| /* Remove all locally rgeistered stuff */ |
| |
| while(s->entries) |
| avahi_entry_free(s, s->entries); |
| |
| avahi_interface_monitor_free(s->monitor); |
| |
| while (s->groups) |
| avahi_entry_group_free(s, s->groups); |
| |
| free_slots(s); |
| |
| avahi_hashmap_free(s->entries_by_key); |
| avahi_record_list_free(s->record_list); |
| avahi_hashmap_free(s->record_browser_hashmap); |
| |
| if (s->wide_area_lookup_engine) |
| avahi_wide_area_engine_free(s->wide_area_lookup_engine); |
| avahi_multicast_lookup_engine_free(s->multicast_lookup_engine); |
| |
| if (s->cleanup_time_event) |
| avahi_time_event_free(s->cleanup_time_event); |
| |
| avahi_time_event_queue_free(s->time_event_queue); |
| |
| /* Free watches */ |
| |
| if (s->watch_ipv4) |
| s->poll_api->watch_free(s->watch_ipv4); |
| if (s->watch_ipv6) |
| s->poll_api->watch_free(s->watch_ipv6); |
| |
| if (s->watch_legacy_unicast_ipv4) |
| s->poll_api->watch_free(s->watch_legacy_unicast_ipv4); |
| if (s->watch_legacy_unicast_ipv6) |
| s->poll_api->watch_free(s->watch_legacy_unicast_ipv6); |
| |
| /* Free sockets */ |
| |
| if (s->fd_ipv4 >= 0) |
| close(s->fd_ipv4); |
| if (s->fd_ipv6 >= 0) |
| close(s->fd_ipv6); |
| |
| if (s->fd_legacy_unicast_ipv4 >= 0) |
| close(s->fd_legacy_unicast_ipv4); |
| if (s->fd_legacy_unicast_ipv6 >= 0) |
| close(s->fd_legacy_unicast_ipv6); |
| |
| /* Free other stuff */ |
| |
| avahi_free(s->host_name); |
| avahi_free(s->domain_name); |
| avahi_free(s->host_name_fqdn); |
| |
| avahi_server_config_free(&s->config); |
| |
| avahi_free(s); |
| } |
| |
| const char* avahi_server_get_domain_name(AvahiServer *s) { |
| assert(s); |
| |
| return s->domain_name; |
| } |
| |
| const char* avahi_server_get_host_name(AvahiServer *s) { |
| assert(s); |
| |
| return s->host_name; |
| } |
| |
| const char* avahi_server_get_host_name_fqdn(AvahiServer *s) { |
| assert(s); |
| |
| return s->host_name_fqdn; |
| } |
| |
| void* avahi_server_get_data(AvahiServer *s) { |
| assert(s); |
| |
| return s->userdata; |
| } |
| |
| void avahi_server_set_data(AvahiServer *s, void* userdata) { |
| assert(s); |
| |
| s->userdata = userdata; |
| } |
| |
| AvahiServerState avahi_server_get_state(AvahiServer *s) { |
| assert(s); |
| |
| return s->state; |
| } |
| |
| AvahiServerConfig* avahi_server_config_init(AvahiServerConfig *c) { |
| assert(c); |
| |
| memset(c, 0, sizeof(AvahiServerConfig)); |
| c->use_ipv6 = 1; |
| c->use_ipv4 = 1; |
| c->allow_interfaces = NULL; |
| c->deny_interfaces = NULL; |
| c->host_name = NULL; |
| c->domain_name = NULL; |
| c->check_response_ttl = 0; |
| c->publish_hinfo = 1; |
| c->publish_addresses = 1; |
| c->publish_workstation = 1; |
| c->publish_domain = 1; |
| c->use_iff_running = 0; |
| c->enable_reflector = 0; |
| c->reflect_ipv = 0; |
| c->add_service_cookie = 0; |
| c->enable_wide_area = 0; |
| c->n_wide_area_servers = 0; |
| c->disallow_other_stacks = 0; |
| c->browse_domains = NULL; |
| c->disable_publishing = 0; |
| c->allow_point_to_point = 0; |
| c->publish_aaaa_on_ipv4 = 1; |
| c->publish_a_on_ipv6 = 0; |
| c->n_cache_entries_max = AVAHI_DEFAULT_CACHE_ENTRIES_MAX; |
| c->ratelimit_interval = 0; |
| c->ratelimit_burst = 0; |
| |
| return c; |
| } |
| |
| void avahi_server_config_free(AvahiServerConfig *c) { |
| assert(c); |
| |
| avahi_free(c->host_name); |
| avahi_free(c->domain_name); |
| avahi_string_list_free(c->browse_domains); |
| avahi_string_list_free(c->allow_interfaces); |
| avahi_string_list_free(c->deny_interfaces); |
| } |
| |
| AvahiServerConfig* avahi_server_config_copy(AvahiServerConfig *ret, const AvahiServerConfig *c) { |
| char *d = NULL, *h = NULL; |
| AvahiStringList *browse = NULL, *allow = NULL, *deny = NULL; |
| assert(ret); |
| assert(c); |
| |
| if (c->host_name) |
| if (!(h = avahi_strdup(c->host_name))) |
| return NULL; |
| |
| if (c->domain_name) |
| if (!(d = avahi_strdup(c->domain_name))) { |
| avahi_free(h); |
| return NULL; |
| } |
| |
| if (!(browse = avahi_string_list_copy(c->browse_domains)) && c->browse_domains) { |
| avahi_free(h); |
| avahi_free(d); |
| return NULL; |
| } |
| |
| if (!(allow = avahi_string_list_copy(c->allow_interfaces)) && c->allow_interfaces) { |
| avahi_string_list_free(browse); |
| avahi_free(h); |
| avahi_free(d); |
| return NULL; |
| } |
| |
| if (!(deny = avahi_string_list_copy(c->deny_interfaces)) && c->deny_interfaces) { |
| avahi_string_list_free(allow); |
| avahi_string_list_free(browse); |
| avahi_free(h); |
| avahi_free(d); |
| return NULL; |
| } |
| |
| *ret = *c; |
| ret->host_name = h; |
| ret->domain_name = d; |
| ret->browse_domains = browse; |
| ret->allow_interfaces = allow; |
| ret->deny_interfaces = deny; |
| |
| return ret; |
| } |
| |
| int avahi_server_errno(AvahiServer *s) { |
| assert(s); |
| |
| return s->error; |
| } |
| |
| /* Just for internal use */ |
| int avahi_server_set_errno(AvahiServer *s, int error) { |
| assert(s); |
| |
| return s->error = error; |
| } |
| |
| uint32_t avahi_server_get_local_service_cookie(AvahiServer *s) { |
| assert(s); |
| |
| return s->local_service_cookie; |
| } |
| |
| static AvahiEntry *find_entry(AvahiServer *s, AvahiIfIndex interface, AvahiProtocol protocol, AvahiKey *key) { |
| AvahiEntry *e; |
| |
| assert(s); |
| assert(key); |
| |
| for (e = avahi_hashmap_lookup(s->entries_by_key, key); e; e = e->by_key_next) |
| |
| if ((e->interface == interface || e->interface <= 0 || interface <= 0) && |
| (e->protocol == protocol || e->protocol == AVAHI_PROTO_UNSPEC || protocol == AVAHI_PROTO_UNSPEC) && |
| (!e->group || e->group->state == AVAHI_ENTRY_GROUP_ESTABLISHED || e->group->state == AVAHI_ENTRY_GROUP_REGISTERING)) |
| |
| return e; |
| |
| return NULL; |
| } |
| |
| int avahi_server_get_group_of_service(AvahiServer *s, AvahiIfIndex interface, AvahiProtocol protocol, const char *name, const char *type, const char *domain, AvahiSEntryGroup** ret_group) { |
| AvahiKey *key = NULL; |
| AvahiEntry *e; |
| int ret; |
| char n[AVAHI_DOMAIN_NAME_MAX]; |
| |
| assert(s); |
| assert(name); |
| assert(type); |
| assert(ret_group); |
| |
| AVAHI_CHECK_VALIDITY(s, AVAHI_IF_VALID(interface), AVAHI_ERR_INVALID_INTERFACE); |
| AVAHI_CHECK_VALIDITY(s, AVAHI_PROTO_VALID(protocol), AVAHI_ERR_INVALID_PROTOCOL); |
| AVAHI_CHECK_VALIDITY(s, avahi_is_valid_service_name(name), AVAHI_ERR_INVALID_SERVICE_NAME); |
| AVAHI_CHECK_VALIDITY(s, avahi_is_valid_service_type_strict(type), AVAHI_ERR_INVALID_SERVICE_TYPE); |
| AVAHI_CHECK_VALIDITY(s, !domain || avahi_is_valid_domain_name(domain), AVAHI_ERR_INVALID_DOMAIN_NAME); |
| |
| if ((ret = avahi_service_name_join(n, sizeof(n), name, type, domain) < 0)) |
| return avahi_server_set_errno(s, ret); |
| |
| if (!(key = avahi_key_new(n, AVAHI_DNS_CLASS_IN, AVAHI_DNS_TYPE_SRV))) |
| return avahi_server_set_errno(s, AVAHI_ERR_NO_MEMORY); |
| |
| e = find_entry(s, interface, protocol, key); |
| avahi_key_unref(key); |
| |
| if (e) { |
| *ret_group = e->group; |
| return AVAHI_OK; |
| } |
| |
| return avahi_server_set_errno(s, AVAHI_ERR_NOT_FOUND); |
| } |
| |
| int avahi_server_is_service_local(AvahiServer *s, AvahiIfIndex interface, AvahiProtocol protocol, const char *name) { |
| AvahiKey *key = NULL; |
| AvahiEntry *e; |
| |
| assert(s); |
| assert(name); |
| |
| if (!s->host_name_fqdn) |
| return 0; |
| |
| if (!(key = avahi_key_new(name, AVAHI_DNS_CLASS_IN, AVAHI_DNS_TYPE_SRV))) |
| return 0; |
| |
| e = find_entry(s, interface, protocol, key); |
| avahi_key_unref(key); |
| |
| if (!e) |
| return 0; |
| |
| return avahi_domain_equal(s->host_name_fqdn, e->record->data.srv.name); |
| } |
| |
| int avahi_server_is_record_local(AvahiServer *s, AvahiIfIndex interface, AvahiProtocol protocol, AvahiRecord *record) { |
| AvahiEntry *e; |
| |
| assert(s); |
| assert(record); |
| |
| for (e = avahi_hashmap_lookup(s->entries_by_key, record->key); e; e = e->by_key_next) |
| |
| if ((e->interface == interface || e->interface <= 0 || interface <= 0) && |
| (e->protocol == protocol || e->protocol == AVAHI_PROTO_UNSPEC || protocol == AVAHI_PROTO_UNSPEC) && |
| (!e->group || e->group->state == AVAHI_ENTRY_GROUP_ESTABLISHED || e->group->state == AVAHI_ENTRY_GROUP_REGISTERING) && |
| avahi_record_equal_no_ttl(record, e->record)) |
| return 1; |
| |
| return 0; |
| } |
| |
| /** Set the wide area DNS servers */ |
| int avahi_server_set_wide_area_servers(AvahiServer *s, const AvahiAddress *a, unsigned n) { |
| assert(s); |
| |
| if (!s->wide_area_lookup_engine) |
| return avahi_server_set_errno(s, AVAHI_ERR_INVALID_CONFIG); |
| |
| avahi_wide_area_set_servers(s->wide_area_lookup_engine, a, n); |
| return AVAHI_OK; |
| } |
| |
| const AvahiServerConfig* avahi_server_get_config(AvahiServer *s) { |
| assert(s); |
| |
| return &s->config; |
| } |
| |
| /** Set the browsing domains */ |
| int avahi_server_set_browse_domains(AvahiServer *s, AvahiStringList *domains) { |
| AvahiStringList *l; |
| |
| assert(s); |
| |
| for (l = s->config.browse_domains; l; l = l->next) |
| if (!avahi_is_valid_domain_name((char*) l->text)) |
| return avahi_server_set_errno(s, AVAHI_ERR_INVALID_DOMAIN_NAME); |
| |
| avahi_string_list_free(s->config.browse_domains); |
| s->config.browse_domains = avahi_string_list_copy(domains); |
| |
| return AVAHI_OK; |
| } |
