git.meshlink.io Git - catta/blob - avahi-core/browse-dns-server.c

   1 /* $Id$ */
   2
   3 /***
   4   This file is part of avahi.
   5
   6   avahi is free software; you can redistribute it and/or modify it
   7   under the terms of the GNU Lesser General Public License as
   8   published by the Free Software Foundation; either version 2.1 of the
   9   License, or (at your option) any later version.
  10
  11   avahi is distributed in the hope that it will be useful, but WITHOUT
  12   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  13   or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General
  14   Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public
  17   License along with avahi; if not, write to the Free Software
  18   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  19   USA.
  20 ***/
  21
  22 #ifdef HAVE_CONFIG_H
  23 #include <config.h>
  24 #endif
  25
  26 #include <string.h>
  27
  28 #include "browse.h"
  29 #include "util.h"
  30 #include "log.h"
  31 #include "rr.h"
  32
  33 typedef struct AvahiDNSServerInfo AvahiDNSServerInfo;
  34
  35 struct AvahiDNSServerInfo {
  36     AvahiDNSServerBrowser *browser;
  37
  38     AvahiIfIndex interface;
  39     AvahiProtocol protocol;
  40     AvahiRecord *srv_record;
  41     AvahiHostNameResolver *host_name_resolver;
  42     AvahiAddress address;
  43
  44     AVAHI_LLIST_FIELDS(AvahiDNSServerInfo, info);
  45 };
  46
  47 struct AvahiDNSServerBrowser {
  48     AvahiServer *server;
  49     gchar *domain_name;
  50
  51     AvahiRecordBrowser *record_browser;
  52     AvahiDNSServerBrowserCallback callback;
  53     gpointer userdata;
  54     AvahiProtocol aprotocol;
  55
  56     guint n_info;
  57
  58     AVAHI_LLIST_FIELDS(AvahiDNSServerBrowser, browser);
  59     AVAHI_LLIST_HEAD(AvahiDNSServerInfo, info);
  60 };
  61
  62 static AvahiDNSServerInfo* get_server_info(AvahiDNSServerBrowser *b, AvahiIfIndex interface, AvahiProtocol protocol, AvahiRecord *r) {
  63     AvahiDNSServerInfo *i;
  64
  65     g_assert(b);
  66     g_assert(r);
  67
  68     for (i = b->info; i; i = i->info_next)
  69         if (i->interface == interface &&
  70             i->protocol == protocol &&
  71             avahi_record_equal_no_ttl(r, i->srv_record))
  72             return i;
  73
  74     return NULL;
  75 }
  76
  77 static void server_info_free(AvahiDNSServerBrowser *b, AvahiDNSServerInfo *i) {
  78     g_assert(b);
  79     g_assert(i);
  80
  81     avahi_record_unref(i->srv_record);
  82     if (i->host_name_resolver)
  83         avahi_host_name_resolver_free(i->host_name_resolver);
  84
  85     AVAHI_LLIST_REMOVE(AvahiDNSServerInfo, info, b->info, i);
  86
  87     g_assert(b->n_info >= 1);
  88     b->n_info--;
  89
  90     g_free(i);
  91 }
  92
  93 static void host_name_resolver_callback(AvahiHostNameResolver *r, AvahiIfIndex interface, AvahiProtocol protocol, AvahiResolverEvent event, const gchar *host_name, const AvahiAddress *a, gpointer userdata) {
  94     AvahiDNSServerInfo *i = userdata;
  95
  96     g_assert(r);
  97     g_assert(host_name);
  98     g_assert(i);
  99
 100     if (event == AVAHI_RESOLVER_FOUND) {
 101         i->address = *a;
 102
 103         i->browser->callback(i->browser, i->interface, i->protocol, AVAHI_BROWSER_NEW, i->srv_record->data.srv.name, &i->address, i->srv_record->data.srv.port, i->browser->userdata);
 104     }
 105
 106     avahi_host_name_resolver_free(i->host_name_resolver);
 107     i->host_name_resolver = NULL;
 108 }
 109
 110 static void record_browser_callback(AvahiRecordBrowser*rr, AvahiIfIndex interface, AvahiProtocol protocol, AvahiBrowserEvent event, AvahiRecord *record, gpointer userdata) {
 111     AvahiDNSServerBrowser *b = userdata;
 112
 113     g_assert(rr);
 114     g_assert(record);
 115     g_assert(b);
 116
 117     g_assert(record->key->type == AVAHI_DNS_TYPE_SRV);
 118
 119     if (event == AVAHI_BROWSER_NEW) {
 120         AvahiDNSServerInfo *i;
 121
 122         if (get_server_info(b, interface, protocol, record))
 123             return;
 124
 125         if (b->n_info >= 10)
 126             return;
 127
 128         i = g_new(AvahiDNSServerInfo, 1);
 129         i->browser = b;
 130         i->interface = interface;
 131         i->protocol = protocol;
 132         i->srv_record = avahi_record_ref(record);
 133         i->host_name_resolver = avahi_host_name_resolver_new(b->server, interface, protocol, record->data.srv.name, b->aprotocol, host_name_resolver_callback, i);
 134
 135         AVAHI_LLIST_PREPEND(AvahiDNSServerInfo, info, b->info, i);
 136
 137         b->n_info++;
 138     } else if (event == AVAHI_BROWSER_REMOVE) {
 139         AvahiDNSServerInfo *i;
 140
 141         if (!(i = get_server_info(b, interface, protocol, record)))
 142             return;
 143
 144         if (!i->host_name_resolver)
 145             b->callback(b, interface, protocol, event, i->srv_record->data.srv.name, &i->address, i->srv_record->data.srv.port, b->userdata);
 146
 147         server_info_free(b, i);
 148     }
 149 }
 150
 151 AvahiDNSServerBrowser *avahi_dns_server_browser_new(AvahiServer *server, AvahiIfIndex interface, AvahiProtocol protocol, const gchar *domain, AvahiDNSServerType type, AvahiProtocol aprotocol, AvahiDNSServerBrowserCallback callback, gpointer userdata) {
 152     AvahiDNSServerBrowser *b;
 153     AvahiKey *k;
 154     gchar *n = NULL;
 155
 156     g_assert(server);
 157     g_assert(callback);
 158     g_assert(type == AVAHI_DNS_SERVER_RESOLVE || type == AVAHI_DNS_SERVER_UPDATE);
 159
 160     if (domain && !avahi_valid_domain_name(domain)) {
 161         avahi_server_set_errno(server, AVAHI_ERR_INVALID_DOMAIN_NAME);
 162         return NULL;
 163     }
 164
 165     b = g_new(AvahiDNSServerBrowser, 1);
 166     b->server = server;
 167     b->domain_name = avahi_normalize_name(domain ? domain : "local");
 168     b->callback = callback;
 169     b->userdata = userdata;
 170     b->aprotocol = aprotocol;
 171     b->n_info = 0;
 172
 173     AVAHI_LLIST_HEAD_INIT(AvahiDNSServerInfo, b->info);
 174     AVAHI_LLIST_PREPEND(AvahiDNSServerBrowser, browser, server->dns_server_browsers, b);
 175
 176     n = g_strdup_printf("%s.%s",type == AVAHI_DNS_SERVER_RESOLVE ? "_domain._udp" : "_dns-update._udp", b->domain_name);
 177     k = avahi_key_new(n, AVAHI_DNS_CLASS_IN, AVAHI_DNS_TYPE_SRV);
 178     g_free(n);
 179
 180     b->record_browser = avahi_record_browser_new(server, interface, protocol, k, record_browser_callback, b);
 181     avahi_key_unref(k);
 182
 183     if (!b->record_browser) {
 184         avahi_dns_server_browser_free(b);
 185         return NULL;
 186     }
 187
 188     return b;
 189 }
 190
 191 void avahi_dns_server_browser_free(AvahiDNSServerBrowser *b) {
 192     g_assert(b);
 193
 194     while (b->info)
 195         server_info_free(b, b->info);
 196
 197     AVAHI_LLIST_REMOVE(AvahiDNSServerBrowser, browser, b->server->dns_server_browsers, b);
 198
 199     if (b->record_browser)
 200         avahi_record_browser_free(b->record_browser);
 201     g_free(b->domain_name);
 202     g_free(b);
 203 }
 204