blob: 08f209b62676083ea8503066a47fa0c082855b9e [file] [log] [blame]
/***
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 <stdlib.h>
#include <avahi-common/domain.h>
#include <avahi-common/timeval.h>
#include <avahi-common/malloc.h>
#include <avahi-common/error.h>
#include "browse.h"
#include "log.h"
#define TIMEOUT_MSEC 5000
struct AvahiSHostNameResolver {
AvahiServer *server;
char *host_name;
AvahiSRecordBrowser *record_browser_a;
AvahiSRecordBrowser *record_browser_aaaa;
AvahiSHostNameResolverCallback callback;
void* userdata;
AvahiRecord *address_record;
AvahiIfIndex interface;
AvahiProtocol protocol;
AvahiLookupResultFlags flags;
AvahiTimeEvent *time_event;
AVAHI_LLIST_FIELDS(AvahiSHostNameResolver, resolver);
};
static void finish(AvahiSHostNameResolver *r, AvahiResolverEvent event) {
assert(r);
if (r->time_event) {
avahi_time_event_free(r->time_event);
r->time_event = NULL;
}
switch (event) {
case AVAHI_RESOLVER_FOUND: {
AvahiAddress a;
assert(r->address_record);
switch (r->address_record->key->type) {
case AVAHI_DNS_TYPE_A:
a.proto = AVAHI_PROTO_INET;
a.data.ipv4 = r->address_record->data.a.address;
break;
case AVAHI_DNS_TYPE_AAAA:
a.proto = AVAHI_PROTO_INET6;
a.data.ipv6 = r->address_record->data.aaaa.address;
break;
default:
abort();
}
r->callback(r, r->interface, r->protocol, AVAHI_RESOLVER_FOUND, r->address_record->key->name, &a, r->flags, r->userdata);
break;
}
case AVAHI_RESOLVER_FAILURE:
r->callback(r, r->interface, r->protocol, event, r->host_name, NULL, r->flags, r->userdata);
break;
}
}
static void time_event_callback(AvahiTimeEvent *e, void *userdata) {
AvahiSHostNameResolver *r = userdata;
assert(e);
assert(r);
avahi_server_set_errno(r->server, AVAHI_ERR_TIMEOUT);
finish(r, AVAHI_RESOLVER_FAILURE);
}
static void start_timeout(AvahiSHostNameResolver *r) {
struct timeval tv;
assert(r);
if (r->time_event)
return;
avahi_elapse_time(&tv, TIMEOUT_MSEC, 0);
r->time_event = avahi_time_event_new(r->server->time_event_queue, &tv, time_event_callback, r);
}
static void record_browser_callback(
AvahiSRecordBrowser*rr,
AvahiIfIndex interface,
AvahiProtocol protocol,
AvahiBrowserEvent event,
AvahiRecord *record,
AvahiLookupResultFlags flags,
void* userdata) {
AvahiSHostNameResolver *r = userdata;
assert(rr);
assert(r);
switch (event) {
case AVAHI_BROWSER_NEW:
assert(record);
assert(record->key->type == AVAHI_DNS_TYPE_A || record->key->type == AVAHI_DNS_TYPE_AAAA);
if (r->interface > 0 && interface != r->interface)
return;
if (r->protocol != AVAHI_PROTO_UNSPEC && protocol != r->protocol)
return;
if (r->interface <= 0)
r->interface = interface;
if (r->protocol == AVAHI_PROTO_UNSPEC)
r->protocol = protocol;
if (!r->address_record) {
r->address_record = avahi_record_ref(record);
r->flags = flags;
finish(r, AVAHI_RESOLVER_FOUND);
}
break;
case AVAHI_BROWSER_REMOVE:
assert(record);
assert(record->key->type == AVAHI_DNS_TYPE_A || record->key->type == AVAHI_DNS_TYPE_AAAA);
if (r->address_record && avahi_record_equal_no_ttl(record, r->address_record)) {
avahi_record_unref(r->address_record);
r->address_record = NULL;
r->flags = flags;
/** Look for a replacement */
if (r->record_browser_aaaa)
avahi_s_record_browser_restart(r->record_browser_aaaa);
if (r->record_browser_a)
avahi_s_record_browser_restart(r->record_browser_a);
start_timeout(r);
}
break;
case AVAHI_BROWSER_CACHE_EXHAUSTED:
case AVAHI_BROWSER_ALL_FOR_NOW:
/* Ignore */
break;
case AVAHI_BROWSER_FAILURE:
/* Stop browsers */
if (r->record_browser_aaaa)
avahi_s_record_browser_free(r->record_browser_aaaa);
if (r->record_browser_a)
avahi_s_record_browser_free(r->record_browser_a);
r->record_browser_a = r->record_browser_aaaa = NULL;
r->flags = flags;
finish(r, AVAHI_RESOLVER_FAILURE);
break;
}
}
AvahiSHostNameResolver *avahi_s_host_name_resolver_new(
AvahiServer *server,
AvahiIfIndex interface,
AvahiProtocol protocol,
const char *host_name,
AvahiProtocol aprotocol,
AvahiLookupFlags flags,
AvahiSHostNameResolverCallback callback,
void* userdata) {
AvahiSHostNameResolver *r;
AvahiKey *k;
assert(server);
assert(host_name);
assert(callback);
AVAHI_CHECK_VALIDITY_RETURN_NULL(server, AVAHI_IF_VALID(interface), AVAHI_ERR_INVALID_INTERFACE);
AVAHI_CHECK_VALIDITY_RETURN_NULL(server, AVAHI_PROTO_VALID(protocol), AVAHI_ERR_INVALID_PROTOCOL);
AVAHI_CHECK_VALIDITY_RETURN_NULL(server, avahi_is_valid_fqdn(host_name), AVAHI_ERR_INVALID_HOST_NAME);
AVAHI_CHECK_VALIDITY_RETURN_NULL(server, AVAHI_PROTO_VALID(aprotocol), AVAHI_ERR_INVALID_PROTOCOL);
AVAHI_CHECK_VALIDITY_RETURN_NULL(server, AVAHI_FLAGS_VALID(flags, AVAHI_LOOKUP_USE_WIDE_AREA|AVAHI_LOOKUP_USE_MULTICAST), AVAHI_ERR_INVALID_FLAGS);
if (!(r = avahi_new(AvahiSHostNameResolver, 1))) {
avahi_server_set_errno(server, AVAHI_ERR_NO_MEMORY);
return NULL;
}
r->server = server;
r->host_name = avahi_normalize_name_strdup(host_name);
r->callback = callback;
r->userdata = userdata;
r->address_record = NULL;
r->interface = interface;
r->protocol = protocol;
r->flags = 0;
r->record_browser_a = r->record_browser_aaaa = NULL;
r->time_event = NULL;
AVAHI_LLIST_PREPEND(AvahiSHostNameResolver, resolver, server->host_name_resolvers, r);
r->record_browser_aaaa = r->record_browser_a = NULL;
if (aprotocol == AVAHI_PROTO_INET || aprotocol == AVAHI_PROTO_UNSPEC) {
k = avahi_key_new(host_name, AVAHI_DNS_CLASS_IN, AVAHI_DNS_TYPE_A);
r->record_browser_a = avahi_s_record_browser_new(server, interface, protocol, k, flags, record_browser_callback, r);
avahi_key_unref(k);
if (!r->record_browser_a)
goto fail;
}
if (aprotocol == AVAHI_PROTO_INET6 || aprotocol == AVAHI_PROTO_UNSPEC) {
k = avahi_key_new(host_name, AVAHI_DNS_CLASS_IN, AVAHI_DNS_TYPE_AAAA);
r->record_browser_aaaa = avahi_s_record_browser_new(server, interface, protocol, k, flags, record_browser_callback, r);
avahi_key_unref(k);
if (!r->record_browser_aaaa)
goto fail;
}
assert(r->record_browser_aaaa || r->record_browser_a);
start_timeout(r);
return r;
fail:
avahi_s_host_name_resolver_free(r);
return NULL;
}
void avahi_s_host_name_resolver_free(AvahiSHostNameResolver *r) {
assert(r);
AVAHI_LLIST_REMOVE(AvahiSHostNameResolver, resolver, r->server->host_name_resolvers, r);
if (r->record_browser_a)
avahi_s_record_browser_free(r->record_browser_a);
if (r->record_browser_aaaa)
avahi_s_record_browser_free(r->record_browser_aaaa);
if (r->time_event)
avahi_time_event_free(r->time_event);
if (r->address_record)
avahi_record_unref(r->address_record);
avahi_free(r->host_name);
avahi_free(r);
}