source3/smbd/avahi_register.c

   1 /*
   2  * Unix SMB/CIFS implementation.
   3  * Register _smb._tcp with avahi
   4  *
   5  * Copyright (C) Volker Lendecke 2009
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 3 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #include "includes.h"
  22 #include "smbd/smbd.h"
  23
  24 #include <avahi-client/client.h>
  25 #include <avahi-client/publish.h>
  26 #include <avahi-common/error.h>
  27 #include <avahi-common/malloc.h>
  28 #include <avahi-common/strlst.h>
  29
  30 struct avahi_state_struct {
  31         struct AvahiPoll *poll;
  32         AvahiClient *client;
  33         AvahiEntryGroup *entry_group;
  34         uint16_t port;
  35 };
  36
  37 static void *avahi_allocator_ctx = NULL;
  38
  39 static void * avahi_allocator_malloc(size_t size)
  40 {
  41         return talloc_size(avahi_allocator_ctx, size);
  42 }
  43
  44 static void avahi_allocator_free(void *p)
  45 {
  46         TALLOC_FREE(p);
  47 }
  48
  49 static void * avahi_allocator_realloc(void *p, size_t size)
  50 {
  51         return talloc_realloc_size(avahi_allocator_ctx, p, size);
  52 }
  53
  54 static void * avahi_allocator_calloc(size_t count, size_t size)
  55 {
  56         void *p = talloc_array_size(avahi_allocator_ctx, size, count);
  57         if (p) {
  58                 memset(p, 0, size * count);
  59         }
  60         return p;
  61 }
  62
  63 static const struct AvahiAllocator avahi_talloc_allocator = {
  64         &avahi_allocator_malloc,
  65         &avahi_allocator_free,
  66         &avahi_allocator_realloc,
  67         &avahi_allocator_calloc
  68 };
  69
  70 static void avahi_entry_group_callback(AvahiEntryGroup *g,
  71                                        AvahiEntryGroupState status,
  72                                        void *userdata)
  73 {
  74         struct avahi_state_struct *state = talloc_get_type_abort(
  75                 userdata, struct avahi_state_struct);
  76         int error;
  77
  78         switch (status) {
  79         case AVAHI_ENTRY_GROUP_ESTABLISHED:
  80                 DBG_DEBUG("AVAHI_ENTRY_GROUP_ESTABLISHED\n");
  81                 break;
  82         case AVAHI_ENTRY_GROUP_FAILURE:
  83                 error = avahi_client_errno(state->client);
  84
  85                 DBG_DEBUG("AVAHI_ENTRY_GROUP_FAILURE: %s\n",
  86                           avahi_strerror(error));
  87                 break;
  88         case AVAHI_ENTRY_GROUP_COLLISION:
  89                 DBG_DEBUG("AVAHI_ENTRY_GROUP_COLLISION\n");
  90                 break;
  91         case AVAHI_ENTRY_GROUP_UNCOMMITED:
  92                 DBG_DEBUG("AVAHI_ENTRY_GROUP_UNCOMMITED\n");
  93                 break;
  94         case AVAHI_ENTRY_GROUP_REGISTERING:
  95                 DBG_DEBUG("AVAHI_ENTRY_GROUP_REGISTERING\n");
  96                 break;
  97         }
  98 }
  99
 100 static void avahi_client_callback(AvahiClient *c, AvahiClientState status,
 101                                   void *userdata)
 102 {
 103         struct avahi_state_struct *state = talloc_get_type_abort(
 104                 userdata, struct avahi_state_struct);
 105         int error;
 106
 107         switch (status) {
 108         case AVAHI_CLIENT_S_RUNNING: {
 109                 int snum;
 110                 int num_services = lp_numservices();
 111                 size_t dk = 0;
 112                 AvahiStringList *adisk = NULL;
 113                 AvahiStringList *adisk2 = NULL;
 114                 const char *hostname = NULL;
 115                 enum mdns_name_values mdns_name = lp_mdns_name();
 116
 117                 DBG_DEBUG("AVAHI_CLIENT_S_RUNNING\n");
 118
 119                 switch (mdns_name) {
 120                 case MDNS_NAME_MDNS:
 121                         hostname = avahi_client_get_host_name(c);
 122                         break;
 123                 case MDNS_NAME_NETBIOS:
 124                         hostname = lp_netbios_name();
 125                         break;
 126                 default:
 127                         DBG_ERR("Unhandled mdns_name %d\n", mdns_name);
 128                         return;
 129                 }
 130
 131                 state->entry_group = avahi_entry_group_new(
 132                         c, avahi_entry_group_callback, state);
 133                 if (state->entry_group == NULL) {
 134                         error = avahi_client_errno(c);
 135                         DBG_DEBUG("avahi_entry_group_new failed: %s\n",
 136                                   avahi_strerror(error));
 137                         break;
 138                 }
 139
 140                 error = avahi_entry_group_add_service(
 141                             state->entry_group, AVAHI_IF_UNSPEC,
 142                             AVAHI_PROTO_UNSPEC, 0, hostname,
 143                             "_smb._tcp", NULL, NULL, state->port, NULL);
 144                 if (error != AVAHI_OK) {
 145                         DBG_DEBUG("avahi_entry_group_add_service failed: %s\n",
 146                                   avahi_strerror(error));
 147                         avahi_entry_group_free(state->entry_group);
 148                         state->entry_group = NULL;
 149                         break;
 150                 }
 151
 152                 for (snum = 0; snum < num_services; snum++) {
 153                         if (lp_snum_ok(snum) &&
 154                             lp_parm_bool(snum, "fruit", "time machine", false))
 155                         {
 156                                 adisk2 = avahi_string_list_add_printf(
 157                                             adisk, "dk%zu=adVN=%s,adVF=0x82",
 158                                             dk++, lp_const_servicename(snum));
 159                                 if (adisk2 == NULL) {
 160                                         DBG_DEBUG("avahi_string_list_add_printf"
 161                                                   "failed: returned NULL\n");
 162                                         avahi_string_list_free(adisk);
 163                                         avahi_entry_group_free(state->entry_group);
 164                                         state->entry_group = NULL;
 165                                         break;
 166                                 }
 167                                 adisk = adisk2;
 168                                 adisk2 = NULL;
 169                         }
 170                 }
 171                 if (dk > 0) {
 172                         adisk2 = avahi_string_list_add(adisk, "sys=adVF=0x100");
 173                         if (adisk2 == NULL) {
 174                                 DBG_DEBUG("avahi_string_list_add failed: "
 175                                           "returned NULL\n");
 176                                 avahi_string_list_free(adisk);
 177                                 avahi_entry_group_free(state->entry_group);
 178                                 state->entry_group = NULL;
 179                                 break;
 180                         }
 181                         adisk = adisk2;
 182                         adisk2 = NULL;
 183
 184                         error = avahi_entry_group_add_service_strlst(
 185                                     state->entry_group, AVAHI_IF_UNSPEC,
 186                                     AVAHI_PROTO_UNSPEC, 0, hostname,
 187                                     "_adisk._tcp", NULL, NULL, 0, adisk);
 188                         avahi_string_list_free(adisk);
 189                         adisk = NULL;
 190                         if (error != AVAHI_OK) {
 191                                 DBG_DEBUG("avahi_entry_group_add_service_strlst "
 192                                           "failed: %s\n", avahi_strerror(error));
 193                                 avahi_entry_group_free(state->entry_group);
 194                                 state->entry_group = NULL;
 195                                 break;
 196                         }
 197                 }
 198
 199                 error = avahi_entry_group_commit(state->entry_group);
 200                 if (error != AVAHI_OK) {
 201                         DBG_DEBUG("avahi_entry_group_commit failed: %s\n",
 202                                   avahi_strerror(error));
 203                         avahi_entry_group_free(state->entry_group);
 204                         state->entry_group = NULL;
 205                         break;
 206                 }
 207                 break;
 208         }
 209         case AVAHI_CLIENT_FAILURE:
 210                 error = avahi_client_errno(c);
 211
 212                 DBG_DEBUG("AVAHI_CLIENT_FAILURE: %s\n", avahi_strerror(error));
 213
 214                 if (error != AVAHI_ERR_DISCONNECTED) {
 215                         break;
 216                 }
 217                 avahi_client_free(c);
 218                 state->client = avahi_client_new(state->poll, AVAHI_CLIENT_NO_FAIL,
 219                                                  avahi_client_callback, state,
 220                                                  &error);
 221                 if (state->client == NULL) {
 222                         DBG_DEBUG("avahi_client_new failed: %s\n",
 223                                   avahi_strerror(error));
 224                         break;
 225                 }
 226                 break;
 227         case AVAHI_CLIENT_S_COLLISION:
 228                 DBG_DEBUG("AVAHI_CLIENT_S_COLLISION\n");
 229                 break;
 230         case AVAHI_CLIENT_S_REGISTERING:
 231                 DBG_DEBUG("AVAHI_CLIENT_S_REGISTERING\n");
 232                 break;
 233         case AVAHI_CLIENT_CONNECTING:
 234                 DBG_DEBUG("AVAHI_CLIENT_CONNECTING\n");
 235                 break;
 236         }
 237 }
 238
 239 void *avahi_start_register(TALLOC_CTX *mem_ctx, struct tevent_context *ev,
 240                            uint16_t port)
 241 {
 242         struct avahi_state_struct *state;
 243         int error;
 244
 245         avahi_allocator_ctx = talloc_new(mem_ctx);
 246         if (avahi_allocator_ctx == NULL) {
 247                 return NULL;
 248         }
 249         avahi_set_allocator(&avahi_talloc_allocator);
 250
 251         state = talloc(mem_ctx, struct avahi_state_struct);
 252         if (state == NULL) {
 253                 return state;
 254         }
 255         state->port = port;
 256         state->poll = tevent_avahi_poll(state, ev);
 257         if (state->poll == NULL) {
 258                 goto fail;
 259         }
 260         state->client = avahi_client_new(state->poll, AVAHI_CLIENT_NO_FAIL,
 261                                          avahi_client_callback, state,
 262                                          &error);
 263         if (state->client == NULL) {
 264                 DBG_DEBUG("avahi_client_new failed: %s\n",
 265                           avahi_strerror(error));
 266                 goto fail;
 267         }
 268         return state;
 269
 270  fail:
 271         TALLOC_FREE(state);
 272         return NULL;
 273 }